Title of invention: Crane
Technical field
[0001]
　The present invention relates to a crane including a telescopic boom.
Background technology
[0002]
　Patent Document 1 discloses a telescopic boom in which a plurality of boom elements are nested (also referred to as a telescopic shape), and a mobile crane provided with a hydraulic telescopic cylinder for extending the telescopic boom. ..
[0003]
　The telescopic boom has a boom connecting pin that connects adjacent and overlapping boom elements. The boom element (hereinafter, referred to as a displaceable boom element) that has been disconnected by the boom connecting pin can be displaced in the longitudinal direction (also referred to as expansion / contraction direction) with respect to other boom elements.
[0004]
　The telescopic cylinder has a rod member and a cylinder member. Such a telescopic cylinder connects a cylinder member to the displaceable boom element via a cylinder connecting pin. When the cylinder member is displaced in the expansion / contraction direction in this state, the displaceable boom element is displaced together with the cylinder member, and the telescopic boom expands / contracts.
Prior art literature
Patent documents
[0005]
Patent Document 1: Japanese Unexamined Patent Publication No. 2012-96928
Outline of the invention
Problems to be solved by the invention
[0006]
　By the way, the crane as described above includes a hydraulic actuator that displaces the boom connecting pin, a hydraulic actuator that displaces the cylinder connecting pin, and a hydraulic circuit that supplies pressure oil to each of these actuators. Such hydraulic circuits are provided, for example, around a telescopic boom. This can reduce the degree of freedom in design around the telescopic boom.
[0007]
　An object of the present invention is to provide a crane capable of increasing the degree of freedom of design around a telescopic boom.
Means to solve problems
[0008]
　The crane according to the present invention includes a telescopic boom having an inner boom element and an outer boom element that are stretchably overlapped with each other, and a telescopic actuator that displaces one of the inner boom element and the outer boom element in the telescopic direction. The first connecting member that detachably connects the telescopic actuator to one boom element, the second connecting member that detachably connects the inner boom element and the outer boom element, and the electrical drive provided in the telescopic actuator. By displace one of the first connecting member and the second connecting member based on the power of the source and the electric drive source, the members connected by the one connecting member are not connected to each other. A first coupling mechanism for switching between coupling states and a position information detecting device for detecting information regarding the position of one coupling member based on the output of an electric drive source are provided.
Effect of the invention
[0009]
　According to the present invention, the degree of freedom in design around the telescopic boom can be improved.
A brief description of the drawing
[0010]
FIG. 1 is a schematic view of a mobile crane according to a first embodiment.
2A to 2E are schematic views for explaining the structure and expansion / contraction operation of the telescopic boom.
FIG. 3A is a perspective view of the actuator.
FIG. 3B is an enlarged view of part A of FIG. 3A.
FIG. 4 is a partial plan view of the actuator.
FIG. 5 is a partial side view of the actuator.
FIG. 6 is a view of an actuator holding a boom connecting pin as viewed from the right side of FIG.
FIG. 7 is a perspective view of a pin displacement module holding a boom connecting pin.
FIG. 8 is a front view of a pin displacement module in an expanded state and holding a boom connecting pin.
FIG. 9 is a view from the left side of FIG.
FIG. 10 is a view from the right side of FIG.
FIG. 11 is a view seen from above in FIG.
FIG. 12 is a front view of a pin displacement module in which the boom connecting mechanism is in the reduced state and the cylinder connecting mechanism is in the expanded state.
FIG. 13 is a front view of a pin displacement module in which the boom connecting mechanism is in the expanded state and the cylinder connecting mechanism is in the reduced state.
FIG. 14A is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 14B is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 14C is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 14D is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 15A is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 15B is a schematic diagram for explaining the operation of the locking mechanism.
FIG. 16 is a timing chart during the extension operation of the telescopic boom.
FIG. 17A is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 17B is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 17C is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 18A is a schematic diagram for explaining the operation of the boom connecting mechanism.
FIG. 18B is a schematic diagram for explaining the operation of the boom connecting mechanism.
FIG. 18C is a schematic diagram for explaining the operation of the boom connecting mechanism.
FIG. 19A is a diagram showing a position information detection device for a crane according to a second embodiment of the present invention.
FIG. 19B is a view of the position information detection device shown in FIG. 19A as viewed from the direction of arrow Ar .
[Figure 19C] FIG. 19C, C of FIG. 19A 1a -C 1a is a cross-sectional view taken along line.
[FIG. 19D] FIG. 19D, C of FIG. 19A 1b -C 1b is a sectional view taken along the line.
FIG. 20 is a diagram for explaining the operation of the position information detecting device of the crane according to the second embodiment.
FIG. 21A is a diagram showing a position information detection device for a crane according to a third embodiment of the present invention.
FIG. 21B is a view of the position information detection device shown in FIG. 21A as viewed from the direction of arrow Ar .
[FIG. 21C] FIG. 21C, C of FIG. 21A 2a -C 2a is a cross-sectional view taken along line.
FIG 21D] FIG 21D is, C in FIG. 21A 2b -C 2b is a sectional view taken along the line.
FIG 21E] FIG 21E is, C in FIG. 21A 2c -C 2c is a sectional view taken along the line.
FIG. 22 is a diagram for explaining the operation of the position information detecting device of the crane according to the third embodiment.
FIG. 23A is a diagram showing a position information detecting device for a crane according to a fourth embodiment of the present invention.
FIG. 23B is a view of the position information detection device shown in FIG. 23A as viewed from the direction of arrow Ar .
[FIG. 23C] FIG. 23C, C of FIG. 23A 3a -C 3a is a sectional view taken along the line.
FIG 23D] FIG 23D is, C in FIG. 23A 3b -C 3b is a sectional view taken along the line.
FIG. 24 is a diagram for explaining the operation of the crane position information detecting device according to the fourth embodiment.
FIG. 25A is a diagram showing a position information detecting device for a crane according to a fifth embodiment of the present invention.
FIG. 25B is a view of the position information detecting device shown in FIG. 25A as viewed from the direction of arrow Ar .
[FIG. 25C] FIG. 25C, C of FIG. 25A 4a -C 4a is a sectional view taken along the line.
FIG. 25D is C of FIG. 25A. It is sectional drawing of 4b- C 4b line.
FIG 25E] FIG 25E is, C in FIG. 25A 4c -C 4c is a sectional view taken along the line.
FIG. 26 is a diagram for explaining the operation of the crane position information detecting device according to the fifth embodiment.
FIG. 27A is a diagram showing a position information detection device for a crane according to a sixth embodiment of the present invention.
FIG. 27B is a view of the position information detection device shown in FIG. 27A as viewed from the direction of arrow Ar .
[FIG. 27C] FIG. 27C, C of FIG. 27A 5a -C 5a is a cross-sectional view taken along line.
FIG 27D] FIG 27D is, C in FIG. 27A 5b -C 5b is a sectional view taken along the line.
FIG. 28 is a diagram for explaining the operation of the crane position information detecting device according to the sixth embodiment.
FIG. 29A is a diagram showing a position information detection device for a crane according to a seventh embodiment of the present invention.
FIG. 29B shows the position information detector shown in FIG. 29A as arrow A. It is a figure seen from the direction of r .
[FIG. 29C] FIG. 29C, C of FIG. 29A 6a -C 6a is a cross-sectional view taken along line.
[Figure 29D] FIG. 29D, C of FIG. 29A 6b -C 6b is a sectional view taken along the line.
FIG 29E] FIG 29E is, C in FIG. 29A 6c -C 6c is a cross-sectional view taken along line.
FIG. 30 is a diagram for explaining the operation of the position information detecting device of the crane according to the seventh embodiment.
FIG. 31A is a diagram showing a position information detection device for a crane according to the eighth embodiment of the present invention.
FIG. 31B is a view of the position information detecting device shown in FIG. 31A as viewed from the direction of arrow Ar .
FIG 31C] FIG 31C is, C in FIG. 31A 7a -C 7a is a sectional view taken along the line.
[Fig. 31D] Fig. 31D shows C 7b- C 7b of FIG. 31A. It is a line sectional view.
FIG. 32 is a diagram for explaining the operation of the position information detecting device of the crane according to the eighth embodiment.
FIG. 33A is a diagram showing a position information detection device for a crane according to a ninth embodiment of the present invention.
FIG. 33B is a view of the position information detection device shown in FIG. 33A as viewed from the direction of arrow Ar .
FIG 33C] FIG 33C is, C in FIG. 33A 8a -C 8a is a cross-sectional view taken along line.
FIG 33D] FIG 33D is, C in FIG. 33A 8b -C 8b is a cross-sectional view taken along line.
FIG 33E] FIG 33E is, C in FIG. 33A 8c -C 8c is a sectional view taken along the line.
FIG. 34 is a diagram for explaining the operation of the crane position information detecting device according to the ninth embodiment.
Mode for carrying out the invention
[0011]
　Hereinafter, some examples of the embodiments according to the present invention will be described in detail with reference to the drawings. It should be noted that each embodiment described below is an example of a mobile crane according to the present invention, and the present invention is not limited to each embodiment.
[0012]
　[1. Embodiment 1]
　FIG. 1 is a schematic view of a mobile crane 1 (rough terrain crane in the case of illustration) according to the present embodiment.
[0013]
　Examples of the mobile crane include an all-terrain crane, a truck crane, and a loaded truck crane (also referred to as a cargo crane). However, the crane according to the present invention is not limited to a mobile crane, and can be applied to other cranes provided with a telescopic boom.
[0014]
　Hereinafter, first, the outline of the mobile crane 1 and the telescopic boom 14 included in the mobile crane 1 will be described. After that, the specific structure and operation of the actuator 2, which is a feature of the mobile crane 1 according to the present embodiment, will be described.
[0015]
　[1.1 Mobile Crane] The
　mobile crane 1 shown in FIG. 1 has a traveling body 10 having a plurality of wheels 101, outriggers 11 provided at four corners of the traveling body 10, and an upper portion of the traveling body 10. A swivel base 12 provided so as to be swivel, a telescopic boom 14 whose base end is fixed to the swivel base 12, an actuator 2 (omitted in FIG. 1) that expands and contracts the telescopic boom 14, and a telescopic boom 14 A undulating cylinder 15 for undulating the undulating boom 14, a wire 16 hanging from the tip of the telescopic boom 14, and a hook 17 provided at the tip of the wire 16 are provided.
[0016]
　[About the telescopic boom]
　Next, the telescopic boom 14 will be described with reference to FIGS. 1 and 2. FIG. 2 is a schematic view for explaining the structure and expansion / contraction operation of the telescopic boom 14.
[0017]
　FIG. 1 shows a telescopic boom 14 in an extended state. On the other hand, FIG. 2A shows a telescopic boom 14 in a contracted state. FIG. 2E shows a telescopic boom 14 in which only the tip boom element 141, which will be described later, is extended.
[0018]
　The telescopic boom 14 is composed of a plurality of (at least a pair) boom elements. Each of the boom elements is tubular and is combined in a telescopic manner. Specifically, in the contracted state, the plurality of boom elements are the tip boom element 141, the intermediate boom element 142, and the proximal boom element 143 in order from the inside.
[0019]
　In the case of the present embodiment, the tip boom element 141 and the intermediate boom element 142 are boom elements that can be displaced in the expansion / contraction direction. The displacement of the base end boom element 143 in the expansion / contraction direction is restricted.
[0020]
　By extending the telescopic boom 14 in order from the boom element (that is, the tip boom element 141) arranged inside, the state transitions from the contracted state shown in FIG. 2A to the extended state shown in FIG.
[0021]
　In the extended state, the intermediate boom element 142 is arranged between the proximal end boom element 143 on the most proximal end side and the distal boom element 141 on the most distal end side. There may be a plurality of intermediate boom elements.
[0022]
　The telescopic boom 14 is substantially the same as the conventionally known telescopic boom, but for convenience of explanation regarding the structure and operation of the actuator 2 described later, the structures of the tip boom element 141 and the intermediate boom element 142 are described below. explain.
[0023]
　[About the tip boom element] The
　tip boom element 141 has a tubular shape and has an internal space that can accommodate the actuator 2. The tip boom element 141 has a pair of cylinder pin receiving portions 141a and a pair of boom pin receiving portions 141b at the base end portion.
[0024]
　The pair of cylinder pin receiving portions 141a are formed coaxially with each other at the base end portion of the tip boom element 141. The pair of cylinder pin receiving portions 141a can be engaged with and disengaged from the pair of cylinder connecting pins 454a and 454b (also referred to as the first connecting member) provided on the cylinder member 32 of the telescopic cylinder 3, respectively (that is, in an engaged state). Or take one of the detached states).
[0025]
　The cylinder connecting pins 454a and 454b are displaced in their own axial direction based on the operation of the cylinder connecting mechanism 45 included in the actuator 2 described later. With the pair of cylinder connecting pins 454a and 454b and the pair of cylinder pin receiving portions 141a engaged, the tip boom element 141 can be displaced in the expansion and contraction direction together with the cylinder member 32.
[0026]
　The pair of boom pin receiving portions 141b are formed coaxially with each other on the proximal end side of the cylinder pin receiving portion 141a. Each of the boom pin receiving portions 141b can be engaged with and detached from the pair of boom connecting pins 144a (also referred to as a second connecting member).
[0027]
　The pair of boom connecting pins 144a connect the tip boom element 141 and the intermediate boom element 142, respectively. The pair of boom connecting pins 144a are displaced in their own axial direction based on the operation of the boom connecting mechanism 46 included in the actuator 2.
[0028]
　In a state where the tip boom element 141 and the intermediate boom element 142 are connected by a pair of boom connecting pins 144a, the boom pin receiving portion 141b of the tip boom element 141 and the first boom pin receiving portion 142b or the first boom pin receiving portion 142b of the intermediate boom element 142 described later (2) The boom connecting pin 144a is inserted through the boom pin receiving portion 142c so as to be bridged.
[0029]
　In a state where the tip boom element 141 and the intermediate boom element 142 are connected (also referred to as a connected state), the tip boom element 141 cannot be displaced with respect to the intermediate boom element 142 in the expansion / contraction direction.
[0030]
　On the other hand, in a state where the tip boom element 141 and the intermediate boom element 142 are disconnected (also referred to as a non-connected state), the tip boom element 141 can be displaced with respect to the intermediate boom element 142 in the expansion / contraction direction.
[0031]
　[About the intermediate boom element] The
　intermediate boom element 142 has a tubular shape as shown in FIG. 2 and has an internal space capable of accommodating the tip boom element 141. The intermediate boom element 142 has a pair of cylinder pin receiving portions 142a, a pair of first boom pin receiving portions 142b, and a pair of third boom pin receiving portions 142d at the base end portion.
[0032]
　The pair of cylinder pin receiving portions 142a and the pair of first boom pin receiving portions 142b are substantially the same as the pair of cylinder pin receiving portions 141a and the pair of boom pin receiving portions 141b of the tip boom element 141, respectively.
[0033]
　The pair of third boom pin receiving portions 142d are formed coaxially with each other on the proximal end side of the pair of first boom pin receiving portions 142b. A boom connecting pin 144b can be inserted into each of the pair of third boom pin receiving portions 142d. The boom connecting pin 144b connects the intermediate boom element 142 and the proximal boom element 143.
[0034]
　Further, the intermediate boom element 142 has a pair of second boom pin receiving portions 142c at the tip end portion. The pair of second boom pin receiving portions 142c are formed coaxially with each other at the tip portions of the intermediate boom element 142. A pair of boom connecting pins 144a can be inserted into each of the pair of second boom pin receiving portions 142c.
[0035]
　[Actuator]
　Hereinafter, the actuator 2 will be described with reference to FIGS. 3A to 18C. The actuator 2 is an actuator that expands and contracts the telescopic boom 14 (see FIGS. 1 and 2) as described above.
[0036]
　First, the outline of the actuator 2 will be described. The actuator 2 is, for example, the tip boom element 141 (also referred to as one boom element) of the tip boom element 141 (also referred to as an inner boom element) and the intermediate boom element 142 (also referred to as an outer boom element) that overlap adjacent to each other. Based on the power of the telescopic cylinder 3 (also referred to as a telescopic actuator), at least one electric motor 41 (also referred to as an electric drive source) provided in the telescopic cylinder 3, and the electric motor 41. By displace the pair of cylinder connecting pins 454a and 454b (also referred to as the first connecting member), the cylinder connecting mechanism 45 (first) that switches between the connected state and the non-connected state of the telescopic cylinder 3 and the tip boom element 141. By displacementing the pair of boom connecting pins 144a (also referred to as the second connecting member) based on the power of the connecting mechanism or the second connecting mechanism) and the electric motor 41, the tip boom element 141 and the intermediate boom element 141 are displaced. A boom connecting mechanism 46 (also referred to as a first connecting mechanism or a second connecting mechanism) for switching between a connected state and a non-connected state with 142 is provided. When the cylinder connecting mechanism 45 is the first connecting mechanism, the boom connecting mechanism 46 is the second connecting mechanism. On the other hand, when the cylinder connecting mechanism 45 is the second connecting mechanism, the boom connecting mechanism 46 becomes the first connecting mechanism.
[0037]
　Next, a specific configuration of each part included in the actuator 2 will be described. The actuator 2 has a telescopic cylinder 3 and a pin displacement module 4. The actuator 2 is arranged in the internal space of the tip boom element 141 in the contracted state (state shown in FIG. 2A) of the telescopic boom 14.
[0038]
　[About the telescopic cylinder] The
　telescopic cylinder 3 has a rod member 31 (also referred to as a fixed side member; see FIG. 2) and a cylinder member 32 (also referred to as a movable side member). Such a telescopic cylinder 3 displaces the boom element (for example, the tip boom element 141 or the intermediate boom element 142) connected to the cylinder member 32 via the cylinder connecting pins 454a and 454b described later in the telescopic direction. Since the telescopic cylinder 3 is almost the same as the conventionally known telescopic cylinder, detailed description thereof will be omitted.
[0039]
　[About the pin displacement module] The
　pin displacement module 4 includes a housing 40, an electric motor 41, a brake mechanism 42, a transmission mechanism 43, a position information detection device 44, a cylinder connecting mechanism 45, a boom connecting mechanism 46, and a lock mechanism 47 ( (See FIG. 8).
[0040]
　Hereinafter, each member constituting the actuator 2 will be described with reference to a state of being incorporated in the actuator 2. Further, in the description of the actuator 2, the Cartesian coordinate system (X, Y, Z) shown in each figure is used. However, the arrangement of each part constituting the actuator 2 is not limited to the arrangement of the present embodiment.
[0041]
　In the Cartesian coordinate system shown in each figure, the X direction coincides with the expansion / contraction direction of the telescopic boom 14 mounted on the mobile crane 1. The + side in the X direction is also referred to as an extension direction in the expansion / contraction direction. On the other hand, the X direction-side is also referred to as a contraction direction in the expansion / contraction direction. Further, the Z direction coincides with, for example, the vertical direction of the mobile crane 1. The Y direction coincides with, for example, the vehicle width direction of the mobile crane 1. However, the Y direction and the Z direction are not limited to the above-mentioned directions as long as they are two directions orthogonal to each other. For example, the Y direction and the Z direction may deviate from the vertical direction and the vehicle width direction of the mobile crane 1 depending on the inclination angle of the telescopic boom 14 and the turning angle of the swivel base 12 with respect to the traveling body 10.
[0042]
　[About the housing] The
　housing 40 is fixed to the cylinder member 32 of the telescopic cylinder 3. The housing 40 accommodates the cylinder connecting mechanism 45 and the boom connecting mechanism 46 in the internal space. Further, the housing 40 supports the electric motor 41 via the transmission mechanism 43. Further, the housing 40 also supports a brake mechanism 42, which will be described later. That is, the housing 40 unitizes each of the above-mentioned members. Such a configuration contributes to the miniaturization of the pin displacement module 4, the improvement of productivity, and the improvement of the reliability of the system.
[0043]
　Specifically, the housing 40 has a box-shaped first housing element 400 and a box-shaped second housing element 401.
[0044]
　The first housing element 400 accommodates a cylinder connecting mechanism 45, which will be described later, in an internal space. A rod member 31 is inserted through the first housing element 400 in the X direction. The end portion of the cylinder member 32 is fixed to the side wall of the first housing element 400 in the X direction + side (left side in FIG. 4 and right side in FIG. 7). The side walls on both sides of the first housing element 400 in the Y direction have through holes 400a and 400b (see FIGS. 3B and 7), respectively.
[0045]
　A pair of cylinder connecting pins 454a and 454b of the cylinder connecting mechanism 45 are inserted into such through holes 400a and 400b, respectively.
[0046]
　The second housing element 401 is provided on the Z direction + side of the first housing element 400. The second housing element 401 accommodates a boom connecting mechanism 46, which will be described later, in the internal space. A transmission shaft 432 (see FIG. 8) of the transmission mechanism 43, which will be described later, is inserted into the second housing element 401 in the X direction.
[0047]
　The side walls on both sides of the second housing element 401 in the Y direction have through holes 401a and 401b (see FIGS. 3B and 7), respectively. A pair of second rack bars 461a and 461b of the boom connecting mechanism 46 are inserted into the through holes 401a and 401b, respectively.
[0048]
　[About the electric motor] The
　electric motor 41 is supported by the housing 40 via the speed reducer 431 of the transmission mechanism 43. Specifically, the electric motor 41 is in a state where the output shaft (not shown) is parallel to the X direction (also referred to as the longitudinal direction of the cylinder member 32), and is around the cylinder member 32 (for example, the Z direction + side). It is arranged around the second housing element 401 (for example, the X direction-side). Such an arrangement can reduce the size of the pin displacement module 4 in the Y direction and the Z direction.
[0049]
　The electric motor 41 as described above is connected to, for example, a power source (not shown) provided on the swivel base 12 via a power supply cable. Further, the electric motor 41 is connected to, for example, a control unit (not shown) provided on the swivel base 12 via a cable for transmitting a control signal.
[0050]
　Each of the above cables can be unwound and wound by a cord reel provided outside the base end of the telescopic boom 14 or on the swivel base 12 (see FIG. 1).
[0051]
　In the mobile crane having a conventional structure, a proximity sensor (not shown) for detecting the positions of the cylinder connecting pins 454a and 454b and the boom connecting pins 144a and 144b, and a power supply cable and a signal transmission cable for each of these proximity sensors are used. Have.
[0052]
　Therefore, it is not necessary to provide new members (for example, cables, cord reels, etc.) for supplying power to the electric motor 41 and transmitting signals. In the case of this embodiment, the positions of the cylinder connecting pins 454a and 454b and the boom connecting pins 144a and 144b are detected by the position information detecting device 44 described later. Therefore, in the present embodiment, the proximity sensor is unnecessary.
[0053]
　Further, the electric motor 41 includes a manual operation unit 410 (see FIG. 3B) that can be operated by a manual handle (not shown). The manual operation unit 410 is for manually performing the state transition of the pin displacement module 4. When the manual operation unit 410 is rotated by the manual handle in the event of a failure or the like, the output shaft of the electric motor 41 rotates and the state of the pin displacement module 4 changes. In the case of the present embodiment, the electric drive source is composed of a single electric motor. However, the electric drive source may be composed of a plurality of (for example, two) electric motors.
[0054]
　[Brake mechanism] The
　brake mechanism 42 applies a braking force to the electric motor 41. Such a brake mechanism 42 prevents the rotation of the output shaft of the electric motor 41 in a state where the electric motor 41 is stopped. As a result, the state of the pin displacement module 4 is maintained when the electric motor 41 is stopped. Further, the brake mechanism 42 allows the electric motor 41 to rotate (that is, slip) when an external force of a predetermined magnitude acts on the cylinder connecting mechanism 45 or the boom connecting mechanism 46 during braking. Such a configuration is effective in preventing damage to the electric motor 41 and each gear constituting the actuator 2. When such a configuration is adopted, for example, a friction brake can be adopted as the brake mechanism 42. The predetermined magnitude of the external force is appropriately determined according to the usage situation and the configuration of the actuator 2.
[0055]
　Specifically, the brake mechanism 42 operates in a reduced state of the cylinder connecting mechanism 45 or a reduced state of the boom connecting mechanism 46, which will be described later, to maintain the states of the cylinder connecting mechanism 45 and the boom connecting mechanism 46.
[0056]
　The brake mechanism 42 is arranged in front of the transmission mechanism 43 described later. Specifically, the brake mechanism 42 is arranged coaxially with the output shaft of the electric motor 41 on the X-direction-side of the electric motor 41 (that is, on the side opposite to the transmission mechanism 43 centering on the electric motor 41). See FIG. 3B). Such an arrangement can reduce the size of the pin displacement module 4 in the Y direction and the Z direction. The front stage means the upstream side (the side closer to the electric motor 41) in the transmission path in which the power of the electric motor 41 is transmitted to the cylinder connecting mechanism 45 or the boom connecting mechanism 46. On the other hand, the latter stage means the downstream side (the side far from the electric motor 41) in the transmission path in which the power of the electric motor 41 is transmitted to the cylinder connecting mechanism 45 or the boom connecting mechanism 46.
[0057]
　Further, if the brake mechanism 42 is arranged in front of the transmission mechanism 43 (reducer 431 described later), the required brake torque is smaller than in the case where the brake mechanism 42 is arranged in the rear stage of the transmission mechanism 43. As a result, the brake mechanism 42 can be downsized.
[0058]
　The brake mechanism 42 may be various brake devices such as a mechanical type and an electromagnetic type. Further, the position of the brake mechanism 42 is not limited to the position of the present embodiment.
[0059]
　[About the transmission mechanism] The
　transmission mechanism 43 transmits the power (that is, rotational motion) of the electric motor 41 to the cylinder connecting mechanism 45 and the boom connecting mechanism 46. The transmission mechanism 43 has a speed reducer 431 and a transmission shaft 432 (see FIG. 8).
[0060]
　The speed reducer 431 decelerates the rotation of the electric motor 41 and transmits it to the transmission shaft 432. The speed reducer 431 is, for example, a planetary gear mechanism housed in the speed reducer case 431a, and is provided coaxially with the output shaft of the electric motor 41. Such an arrangement can reduce the size of the pin displacement module 4 in the Y direction and the Z direction.
[0061]
　The end of the transmission shaft 432 on the − side in the X direction is connected to the output shaft (not shown) of the speed reducer 431. In this state, the transmission shaft 432 rotates together with the output shaft of the speed reducer 431. The transmission shaft 432 inserts the housing 40 (specifically, the second housing element 401) in the X direction. The transmission shaft 432 may be integrated with the output shaft of the speed reducer 431.
[0062]
　The end of the transmission shaft 432 on the X direction + side protrudes from the housing 40 on the X direction + side. A detection unit 44a of the position information detection device 44, which will be described later, is provided at the end of the transmission shaft 432 on the + side in the X direction.
[0063]
　[About the position information detection device] The
　position information detection device 44 has a pair of cylinder connecting pins 454a and 454b and a pair of boom connecting pins 144a (a pair of boom connecting pins 144a) based on the output of the electric motor 41 (for example, rotational displacement of the output shaft). The boom connecting pin 144b may be used. The same shall apply hereinafter) to detect information regarding the position. Information on the position includes, for example, the amount of displacement of the pair of cylinder connecting pins 454a, 454b or the pair of boom connecting pins 144a from the reference position.
[0064]
　Specifically, the position information detection device 44 engages a pair of cylinder connecting pins 454a and 454b with a pair of cylinder pin receiving portions 141a of a boom element (for example, a tip boom element 141) (for example, FIG. 2A). Information about the positions of the pair of cylinder connecting pins 454a and 454b in the state shown in (1) or the detached state (the state shown in FIG. 2E) is detected.
[0065]
　Further, the position information detection device 44 includes a pair of boom connecting pins 144a and a pair of first boom pin receiving portions 142b (may be a pair of second boom pin receiving portions 142c) of the boom element (for example, the intermediate boom element 142). Detects information about the position of the pair of boom connecting pins 144a in the engaged state (eg, the state shown in FIGS. 2A, 2D) or the disengaged state (eg, the state shown in FIG. 2B).
[0066]
　The information regarding the positions of the pair of cylinder connecting pins 454a and 454b and the pair of boom connecting pins 144a and 144b detected in this way is used for various controls of the actuator 2 including, for example, operation control of the electric motor 41.
[0067]
　Such a position information detection device 44 includes a detection unit 44a and a control unit 44b (see FIGS. 17A and 18A).
[0068]
　The detection unit 44a is, for example, a rotary encoder and outputs information (for example, a pulse signal or a code signal) according to the rotational displacement of the output shaft of the electric motor 41. The output method of the rotary encoder is not particularly limited, and may be an incremental method that outputs a pulse signal (relative angle signal) according to the amount of rotational displacement (rotation angle) from the measurement start position, or an absolute method with respect to the reference point. An absolute method that outputs a code signal (absolute angle signal) corresponding to the angle position may be used.
[0069]
　If the detection unit 44a is an absolute rotary encoder, the position information detection device 44 can connect the pair of cylinder connecting pins 454a and 454b and the pair of booms even when the control unit 44b returns from the non-energized state to the energized state. Information about the position of pin 144a can be detected.
[0070]
　The detection unit 44a is provided on the output shaft of the electric motor 41 or a rotating member (for example, a rotating shaft, a gear, etc.) that rotates together with the output shaft. Specifically, in the case of the present embodiment, the detection unit 44a is provided at the end of the transmission shaft 432 (also referred to as a rotating member) on the + side in the X direction. In other words, in the case of the present embodiment, the detection unit 44a is provided after the speed reducer 431 (that is, on the + side in the X direction).
[0071]
　In the case of this embodiment, the detection unit 44a outputs information according to the rotational displacement of the transmission shaft 432. The rotation speed (rotation speed) of the transmission shaft 432 is the rotation speed (rotation speed) of the electric motor 41 decelerated by the speed reducer 431. In the case of the present embodiment, as the detection unit 44a, a rotary encoder capable of obtaining sufficient resolution with respect to the rotation speed (rotation speed) of the transmission shaft 432 is adopted. Since the first missing tooth gear 450 of the cylinder connecting mechanism 45 and the second missing tooth gear 460 of the boom connecting mechanism 46 are fixed to the transmission shaft 432, the information output by the detection unit 44a can be obtained. It is also information according to the rotational displacement of the first missing tooth gear 450 and the second missing tooth gear 460.
[0072]
　The detection unit 44a having the above configuration sends information according to the rotational displacement of the output shaft of the electric motor 41 to the control unit 44b. Upon receiving the information, the control unit 44b calculates information regarding the positions of the pair of cylinder connecting pins 454a and 454b or the pair of boom connecting pins 144a based on the received information. Then, the control unit 44b controls the electric motor 41 based on the calculation result.
[0073]
　The control unit 44b is, for example, an in-vehicle computer composed of an input terminal, an output terminal, a CPU, a memory, and the like. The control unit 44b calculates information regarding the positions of the pair of cylinder connecting pins 454a and 454b or the boom connecting pin 144a based on the output of the detecting unit 44a.
[0074]
　Specifically, for example, the control unit 44b receives information on the output of the detection unit 44a and the positions of the pair of cylinder connecting pins 454a and 454b and the pair of boom connecting pins 144a (for example, the amount of displacement from the reference position). Information on the above positions is calculated using data showing the correlation (table, map, etc.).
[0075]
　When the output of the detection unit 44a is a code signal, data showing the correlation between each code signal and the amount of displacement of the pair of cylinder connecting pins 454a and 454b and the pair of boom connecting pins 144a from the reference position (table). , Map, etc.) to calculate the information about the above position.
[0076]
　The control unit 44b as described above is provided on the swivel base 12. However, the position where the control unit 44b is provided is not limited to the swivel base 12. The control unit 44b may be provided, for example, in a case (not shown) in which the detection unit 44a is arranged.
[0077]
　The position of the detection unit 44a is not limited to the position of the present embodiment. For example, the detection unit 44a may be arranged in front of the speed reducer 431 (that is, on the X-direction-side). That is, the detection unit 44a may acquire information to be transmitted to the control unit 44b based on the rotation of the electric motor 41 before being decelerated by the speed reducer 431. The configuration in which the detection unit 44a is arranged in the front stage of the speed reducer 431 has higher resolution than the configuration in which the detection unit 44a is arranged in the rear stage of the speed reducer 431. In this case, the detection unit 44a may be arranged on the + side in the X direction or the − side in the X direction with respect to the brake mechanism 42.
[0078]
　The detection unit 44a is not limited to the rotary encoder described above. For example, the detection unit 44a may be a limit switch. The limit switch is arranged after the speed reducer 431. Such a limit switch is mechanically operated based on the output of the electric motor 41. Alternatively, the detection unit 44a may be a proximity sensor. The proximity sensor is arranged after the speed reducer 431. Further, the proximity sensor is arranged so as to face the member that rotates based on the output of the electric motor 41. Such a proximity sensor outputs a signal based on the distance to the rotating member. Then, the control unit 44b controls the operation of the electric motor 41 based on the output of the limit switch or the proximity sensor.
[0079]
　[Cylinder connection mechanism] The
　cylinder connection mechanism 45 operates based on the power (that is, rotational movement) of the electric motor 41, and is in an expanded state (also referred to as a first state, see FIGS. 8 and 12) and a reduced state. (Also referred to as the second state. See FIG. 13).
[0080]
　In the expanded state, the pair of cylinder connecting pins 454a and 454b, which will be described later, and the pair of cylinder pin receiving portions 141a of the boom element (for example, the tip boom element 141) are engaged (also referred to as a cylinder pin inserted state). Will be. In the engaged state, the boom element and the cylinder member 32 are connected.
[0081]
　On the other hand, in the reduced state, the pair of cylinder connecting pins 454a and 454b and the pair of cylinder pin receiving portions 141a (see FIG. 2) are separated from each other (the state shown in FIG. 2E, which is also referred to as the cylinder pin withdrawal state. ). In the detached state, the boom element and the cylinder member 32 are disconnected.
[0082]
　Hereinafter, a specific configuration of the cylinder connecting mechanism 45 will be described. The cylinder connecting mechanism 45 includes a first missing tooth gear 450, a first rack bar 451, a first gear mechanism 452, a second gear mechanism 453, a pair of cylinder connecting pins 454a and 454b, and a first urging mechanism 455. In the case of this embodiment, a pair of cylinder connecting pins 454a and 454b are incorporated in the cylinder connecting mechanism 45. However, the pair of cylinder connecting pins 454a and 454b may be provided independently of the cylinder connecting mechanism 45.
[0083]
　[About the first missing tooth gear]
　The first missing tooth gear 450 (also referred to as a switch gear) has a substantially annular plate shape and has a first tooth portion 450a (see FIG. 9) on a part of the outer peripheral surface. .. The first missing tooth gear 450 is fitted and fixed to the transmission shaft 432 and rotates together with the transmission shaft 432.
[0084]
　Such a first missing tooth gear 450 constitutes a switch gear together with a second missing tooth gear 460 (see FIG. 8) of the boom connecting mechanism 46. The switch gear selectively transmits the power of the electric motor 41 to one of the cylinder connecting mechanism 45 and the boom connecting mechanism 46.
[0085]
　In the case of the present embodiment, the first missing tooth gear 450 and the second missing tooth gear 460, which are switch gears, are connected to the cylinder connecting mechanism 45, which is the first connecting mechanism, and the boom connecting mechanism 46, which is the second connecting mechanism, respectively. It has been incorporated. However, the switch gear may be provided independently of the first connecting mechanism and the second connecting mechanism.
[0086]
　In the following description, the rotation direction of the first missing gear 450 (arrow in FIG. 17A) when the cylinder connecting mechanism 45 transitions from the expanded state (see FIGS. 8 and 12) to the reduced state (see FIG. 13). F 1 direction indicated by) is the "front side" in the rotational direction of the first toothless gear 450.
[0087]
　On the other hand, the rotation direction of the first missing tooth gear 450 when the state transitions from the reduced state to the expanded state is the "rear side" in the rotation direction of the first missing tooth gear 450.
[0088]
　Among the convex portions constituting the first tooth portion 450a, the convex portion provided on the frontmost side in the rotation direction of the first missing tooth gear 450 is a positioning tooth (not shown).
[0089]
　[About the first rack bar]
　The first rack bar 451 is displaced in its own longitudinal direction (also referred to as the Y direction) in accordance with the rotation of the first missing tooth gear 450. The first rack bar 451 is located on the most Y-direction-side in the expanded state (see FIGS. 8 and 12). On the other hand, the first rack bar 451 is located on the + side in the Y direction most in the reduced state (see FIG. 13).
[0090]
　When the first missing tooth gear 450 rotates to the front side in the rotation direction during the state transition from the expanded state to the contracted state, the first rack bar 451 is displaced in the Y direction + side (also referred to as one in the longitudinal direction).
[0091]
　On the other hand, when the first missing tooth gear 450 rotates to the rear side in the rotation direction when the state transitions from the reduced state to the expanded state, the first rack bar 451 is also referred to as the Y direction − side (also referred to as the other in the longitudinal direction). ). Hereinafter, a specific configuration of the first rack bar 451 will be described.
[0092]
　The first rack bar 451 is, for example, a shaft member long in the Y direction, and is arranged between the first missing tooth gear 450 and the rod member 31. In this state, the longitudinal direction of the first rack bar 451 coincides with the Y direction.
[0093]
　The first rack bar 451 has a first rack tooth portion 451a on a surface closer to the first missing tooth gear 450 (also referred to as a + side in the Z direction). The first rack tooth portion 451a meshes with the first tooth portion 450a of the first missing tooth gear 450 only at the time of the above-mentioned state transition.
[0094]
　In the expanded state shown in FIGS. 8 and 10, the first end surface (not shown) on the Y direction + side of the first rack tooth portion 451a is a positioning tooth (not shown) in the first tooth portion 450a of the first missing tooth gear 450. ), Or opposes in the Y direction through a slight gap.
[0095]
　In the expanded state, when the first missing tooth gear 450 rotates forward in the rotation direction, the positioning tooth presses the first end surface in the Y direction + side, and the first rack bar 451 is displaced in the Y direction + side.
[0096]
　Then, the tooth portion existing on the rear side of the positioning tooth in the rotation direction of the first tooth portion 450a meshes with the first rack tooth portion 451a. As a result, the first rack bar 451 is displaced in the Y direction + side according to the rotation of the first missing tooth gear 450.
[0097]
　When the first missing tooth gear 450 rotates to the rear side in the rotation direction from the expanded state shown in FIG. 8, the first rack tooth portion 451a and the first tooth portion 450a of the first missing tooth gear 450 are different from each other. Does not mesh.
[0098]
　Further, the first rack bar 451 has a second rack tooth portion 451b and a third rack tooth portion 451c (see FIG. 8) on a surface far from the first missing tooth gear 450 (also referred to as a Z direction − side). Have. The second rack tooth portion 451b meshes with the first gear mechanism 452, which will be described later. On the other hand, the third rack tooth portion 451c meshes with the second gear mechanism 453, which will be described later.
[0099]
　[About the first gear mechanism]
　The first gear mechanism 452 is composed of a plurality of (three in the case of the present embodiment) gear elements 452a, 452b, and 452c (see FIG. 8), each of which is a spur gear. Specifically, the gear element 452a, which is an input gear, meshes with the second rack tooth portion 451b and the gear element 452b of the first rack bar 451. In the expanded state (see FIGS. 8 and 12), the gear element 452a meshes with the tooth portion on the Y-direction + side end or the portion near the end of the second rack tooth portion 451b of the first rack bar 451.
[0100]
　The gear element 452b, which is an intermediate gear, meshes with the gear element 452a and the gear element 452c.
[0101]
　The gear element 452c, which is an output gear, meshes with the gear element 452b and the pin-side rack tooth portion 454c of one of the cylinder connecting pins 454a described later. In the expanded state, the gear element 452c meshes with the Y-direction-side end of one cylinder connecting pin 454a on the pin-side rack tooth portion 454c (see FIG. 8). The gear element 452c rotates in the same direction as the gear element 452a.
[0102]
　[About the second gear mechanism]
　The second gear mechanism 453 includes a plurality of (two in the case of the present embodiment) gear elements 453a and 453b (see FIG. 8), each of which is a spur gear. Specifically, the gear element 453a, which is an input gear, meshes with the third rack tooth portion 451c and the gear element 453b of the first rack bar 451. In the expanded state, the gear element 453a meshes with the end on the + side in the Y direction of the third rack tooth portion 451c of the first rack bar 451.
[0103]
　The gear element 453b, which is an output gear, meshes with the gear element 453a and the pin-side rack tooth portion 454d (see FIG. 8) of the other cylinder connecting pin 454b described later. In the expanded state, the gear element 453b meshes with the Y-direction + side end of the pin-side rack tooth portion 454d of the other cylinder connecting pin 454b. The gear element 453b rotates in the direction opposite to that of the gear element 453a.
[0104]
　As described above, in the case of the present embodiment, the rotation direction of the gear element 452c of the first gear mechanism 452 and the rotation direction of the gear element 453b of the second gear mechanism 453 are opposite directions.
[0105]
　[Cylinder connecting pins] The
　pair of cylinder connecting pins 454a and 454b have their central axes aligned in the Y direction and are coaxial with each other. Hereinafter, in the description of the pair of cylinder connecting pins 454a and 454b, the tip end portion is an end portion on a side far from each other, and the base end portion is an end portion on a side close to each other.
[0106]
　Each of the pair of cylinder connecting pins 454a and 454b has pin-side rack teeth 454c and 454d (see FIG. 8) on the outer peripheral surface. On the other hand, the pin-side rack tooth portion 454c of the cylinder connecting pin 454a (also referred to as the + side in the Y direction) meshes with the gear element 452c of the first gear mechanism 452.
[0107]
　One of the cylinder connecting pins 454a is displaced in its own axial direction (that is, in the Y direction) as the gear element 452c in the first gear mechanism 452 rotates. Specifically, one of the cylinder connecting pins 454a is displaced in the Y direction + side when the state transitions from the reduced state to the expanded state. On the other hand, one of the cylinder connecting pins 454a is displaced in the Y direction − side when the state transitions from the expanded state to the contracted state.
[0108]
　On the other hand (also referred to as the Y direction-side), the pin-side rack tooth portion 454d of the cylinder connecting pin 454b meshes with the gear element 453b of the second gear mechanism 453. The other cylinder connecting pin 454b is displaced in its own axial direction (that is, in the Y direction) as the gear element 453b in the second gear mechanism 453 rotates.
[0109]
　Specifically, the other cylinder connecting pin 454b is displaced in the Y direction − side when the state transitions from the reduced state to the expanded state. On the other hand, the other cylinder connecting pin 454b is displaced in the Y direction + side when the state transitions from the expanded state to the contracted state. That is, in the above-mentioned state transition, the pair of cylinder connecting pins 454a and 454b are displaced in opposite directions in the Y direction.
[0110]
　The pair of cylinder connecting pins 454a and 454b are inserted into the through holes 400a and 400b of the first housing element 400, respectively. In this state, the tips of the pair of cylinder connecting pins 454a and 454b each project to the outside of the first housing element 400.
[0111]
　[About the first urging mechanism]
　The first urging mechanism 455 automatically returns the cylinder connecting mechanism 45 to the expanded state when the electric motor 41 is de-energized in the reduced state of the cylinder connecting mechanism 45. For this purpose, the first urging mechanism 455 urges the pair of cylinder connecting pins 454a and 454b in a direction away from each other.
[0112]
　Specifically, the first urging mechanism 455 is composed of a pair of coil springs 455a and 455b (see FIG. 8). The pair of coil springs 455a and 455b respectively urge the base end portions of the pair of cylinder connecting pins 454a and 454b toward the tip end side.
[0113]
　When the brake mechanism 42 is operating, the cylinder connecting mechanism 45 does not automatically return.
[0114]
　[Summary of Operation of Cylinder Connecting Mechanism]
　An example of the operation of the cylinder connecting mechanism 45 described above will be briefly described with reference to FIGS. 17A to 17C. 17A to 17C are schematic views for explaining the operation of the cylinder connecting mechanism 45. FIG. 17A is a schematic view showing an expanded state of the cylinder connecting mechanism 45 and an engaging state of a pair of cylinder connecting pins 454a and 454b and a pair of cylinder pin receiving portions 141a of the tip boom element 141. FIG. 17B is a schematic view showing a state in which the cylinder connecting mechanism 45 is in the process of transitioning from the expanded state to the contracted state. Further, FIG. 17C is a schematic view showing a reduced state of the cylinder connecting mechanism 45 and a detached state of the pair of cylinder connecting pins 454a and 454b and the pair of cylinder pin receiving portions 141a of the tip boom element 141.
[0115]
　The cylinder connecting mechanism 45 as described above is in an expanded state (see FIGS. 8, 12, and 17A) and a reduced state (see FIGS. 13 and 17C) based on the power (that is, rotational motion) of the electric motor 41. State transition between and. Hereinafter, with reference to FIGS. 17A to 17C, the operation of each part when the cylinder connecting mechanism 45 transitions from the expanded state to the contracted state will be described. In addition, in FIGS. 17A to 17C, the first missing tooth gear 450 and the second missing tooth gear 460 are schematically shown as an integrated missing tooth gear. Hereinafter, for convenience of explanation, this integrated missing tooth gear will be described as the first missing tooth gear 450. Further, in FIGS. 17A to 17C, the lock mechanism 47 described later is omitted.
[0116]
　At the time of the state transition from the expanded state to the reduced state, the power of the electric motor 41 is transmitted to the pair of cylinder connecting pins 454a and 454b in the following first path and second path.
[0117]
　The first path is the path of the first missing tooth gear 450 → the first rack bar 451 → the first gear mechanism 452 → one of the cylinder connecting pins 454a.
[0118]
　On the other hand, the second path is the path of the first missing tooth gear 450 → the first rack bar 451 → the second gear mechanism 453 → the other cylinder connecting pin 454b.
[0119]
　More specifically, first, in the first path and the second path, on the basis of the power of the electric motor 41, the first toothless gear 450 is the front side of the rotational direction (in FIG. 17A arrows F 1 is rotated in the direction indicated by) ..
[0120]
　When the first missing tooth gear 450 rotates in the front side in the rotation direction in the first path and the second path, the first rack bar 451 moves to the + side in the Y direction (right side in FIGS. 17A to 17C) according to the rotation. Displace.
[0121]
　Then, when the first rack bar 451 is displaced to the + side in the Y direction in the first path, one cylinder connecting pin 454a is displaced to the Y direction − side (left side in FIGS. 17A to 17C) via the first gear mechanism 452. Displace to.
[0122]
　On the other hand, when the first rack bar 451 is displaced in the Y direction + side in the second path, the other cylinder connecting pin 454b is displaced in the Y direction + side via the second gear mechanism 453. That is, at the time of the state transition from the expanded state to the reduced state, one cylinder connecting pin 454a and the other cylinder connecting pin 454b are displaced in a direction approaching each other.
[0123]
　In the position information detection device 44, the pair of cylinder connecting pins 454a and 454b are separated from the pair of cylinder pin receiving portions 141a of the tip boom element 141, and are in predetermined positions (for example, the positions shown in FIGS. 2E and 17C). Detects that it has been displaced to. Then, based on the detection result, the control unit 44b stops the operation of the electric motor 41.
[0124]
　The state transition from the reduced state to the expanded state (that is, the state transition from FIG. 17C to FIG. 17A) is performed by the first urging mechanism 455 when the brake mechanism 42 is released in the non-energized state of the electric motor 41. It is done automatically based on the urging force. At this time, one cylinder connecting pin 454a and the other cylinder connecting pin 454b are displaced in a direction away from each other. In the position information detecting device 44, the pair of cylinder connecting pins 454a and 454b are engaged with the pair of cylinder pin receiving portions 141a of the tip boom element 141, and the predetermined positions (for example, the positions shown in FIGS. 2A and 17A). ) Is detected. The detection result is used to control the next operation of the actuator 2.
[0125]
　[About the boom connecting mechanism] The
　boom connecting mechanism 46 is in an expanded state (also referred to as a first state; see FIGS. 8 and 13) and a reduced state (also referred to as a second state) based on the rotation of the electric motor 41. State transition between and (see).
[0126]
　In the expanded state, the boom connecting mechanism 46 takes either an engaged state or a disengaged state with respect to the boom connecting pins (for example, a pair of boom connecting pins 144a).
[0127]
　The boom connecting mechanism 46 disengages the boom connecting pin from the boom element by transitioning from the expanded state to the contracted state in a state of being engaged with the boom connecting pin.
[0128]
　Further, the boom connecting mechanism 46 engages the boom connecting pin with the boom element by changing the state from the reduced state to the expanded state in the state of being engaged with the boom connecting pin.
[0129]
　Hereinafter, a specific configuration of the boom connecting mechanism 46 will be described. The boom connecting mechanism 46 includes a second missing tooth gear 460 (see FIG. 8), a pair of second rack bars 461a and 461b, a synchronous gear 462 (see FIGS. 17A to 17C), and a second urging mechanism 463.
[0130]
　[About the second missing tooth gear]
　The second missing tooth gear 460 (also referred to as a switch gear) has a substantially circular ring plate shape, and has a second tooth portion 460a on a part of the outer peripheral surface in the circumferential direction.
[0131]
　The second missing tooth gear 460 is externally fitted and fixed on the transmission shaft 432 in the X direction + side of the first missing tooth gear 450, and rotates together with the transmission shaft 432. The second missing tooth gear 460 may be a missing tooth gear integrated with the first missing tooth gear 450, for example, as shown in the schematic views shown in FIGS. 14A to 14D.
[0132]
　Hereinafter, the boom coupling mechanism 46 is extended state (FIG. 8, see FIG. 13) when the state transition to the reduced state (see FIG. 12) from the rotating direction (FIG. 8 of the second toothless gear 460 arrow F 2 shown in Direction) is the "front side" in the rotation direction of the second missing tooth gear 460.
[0133]
　On the other hand, when the state transition from the reduced state to the expanded state, the rotational direction of the second toothless gear 460 (arrow R in FIG. 8 2 direction indicated by) is, after "in the rotational direction of the second toothless gear 460 "Side".
[0134]
　Among the convex portions constituting the second tooth portion 460a, the convex portion provided on the frontmost side in the rotation direction of the second missing tooth gear 460 is the positioning tooth 460b (see FIG. 8).
[0135]
　Note that FIG. 8 is a view of the pin displacement module 4 viewed from the + side in the X direction. Therefore, in the case of the present embodiment, the front-rear direction in the rotation direction of the second missing tooth gear 460 is opposite to the front-rear direction in the rotation direction of the first missing tooth gear 450.
[0136]
　That is, the rotation direction of the second missing tooth gear 460 when the boom connecting mechanism 46 changes from the expanded state to the reduced state is the first missing tooth gear when the cylinder connecting mechanism 45 changes from the expanded state to the reduced state. It is opposite to the direction of rotation of 450.
[0137]
　[About the second rack bar] The
　pair of second rack bars 461a and 461b are respectively displaced in the Y direction (also referred to as the axial direction) with the rotation of the second missing tooth gear 460. The second rack bar 461a on one side (also referred to as the + side in the X direction) and the second rack bar 461b on the other side (also referred to as the − side in the X direction) are displaced in opposite directions in the Y direction.
[0138]
　On the other hand, the second rack bar 461a is located on the most Y-direction-side in the expanded state. The other second rack bar 461b is located on the + side in the Y direction most in the expanded state.
[0139]
　Further, one of the second rack bars 461a is located on the + side in the Y direction most in the reduced state. The other second rack bar 461b is located on the most Y-direction-side in the reduced state.
[0140]
　The displacement of one second rack bar 461a in the Y direction + side and the displacement of the other second rack bar 461b in the Y direction-side are, for example, the stopper surface 48 provided on the housing 40 (FIG. It is regulated by contact with (see 14D).
[0141]
　Hereinafter, a specific configuration of the pair of second rack bars 461a and 461b will be described. The pair of second rack bars 461a and 461b are shaft members long in the Y direction, respectively, and are arranged parallel to each other. The pair of second rack bars 461a and 461b are respectively arranged on the + side in the Z direction with respect to the first rack bar 451. Further, the pair of second rack bars 461a and 461b are arranged around the synchronous gear 462, which will be described later, in the X direction. The longitudinal direction of each of the pair of second rack bars 461a and 461b coincides with the Y direction.
[0142]
　The pair of second rack bars 461a and 461b have synchronous rack teeth 461e and 461f (see FIGS. 17A to 17C) on the side surfaces facing in the X direction, respectively. The synchronization rack teeth 461e and 461f mesh with the synchronization gear 462, respectively.
[0143]
　In other words, the synchronous rack teeth 461e and 461f mesh with each other via the synchronous gear 462. With this configuration, one second rack bar 461a and the other second rack bar 461b are displaced in opposite directions in the Y direction.
[0144]
　The pair of second rack bars 461a and 461b each have locking claw portions 461g and 461h (also referred to as locking portions, see FIG. 8) at the tip portions. When the boom connecting pins 144a and 144b are displaced, such locking claw portions 461g and 461h engage with the pin side receiving portions 144c (see FIG. 8) provided on the boom connecting pins 144a and 144b.
[0145]
　On the other hand, the second rack bar 461a has a drive rack tooth portion 461c (see FIG. 8) on a surface close to the second missing tooth gear 460 (also referred to as a + side in the Z direction). The drive rack tooth portion 461c meshes with the second tooth portion 460a of the second missing tooth gear 460.
[0146]
　In the expanded state (see FIG. 8), the first end surface 461d on the + side in the Y direction of the drive rack tooth portion 461c comes into contact with the positioning tooth 460b in the second tooth portion 460a of the second missing tooth gear 460, or slightly. It faces in the Y direction through a gap.
[0147]
　When the second missing tooth gear 460 rotates forward in the rotation direction from the expanded state, the positioning tooth 460b presses the first end surface 461d in the Y direction + side. With such pressing, one second rack bar 461a is displaced to the + side in the Y direction.
[0148]
　When one second rack bar 461a is displaced in the Y direction + side, the synchronous gear 462 rotates and the other second rack bar 461b is on the Y direction-side (that is, the side opposite to one second rack bar 461a). Displace to.
[0149]
　[About the second urging mechanism]
　The second urging mechanism 463 automatically returns the boom connecting mechanism 46 to the expanded state when the electric motor 41 is de-energized in the reduced state of the boom connecting mechanism 46. When the brake mechanism 42 is operating, the boom connecting mechanism 46 does not automatically return.
[0150]
　For this purpose, the second urging mechanism 463 urges the pair of second rack bars 461a and 461b in a direction away from each other. Specifically, the second urging mechanism 463 is composed of a pair of coil springs 463a and 463b (see FIGS. 17A to 17C). The pair of coil springs 463a and 463b respectively urge the base end portions of the pair of second rack bars 461a and 461b toward the tip end side.
[0151]
　[Summary of Operation of Boom Connecting Mechanism]
　An example of the operation of the boom connecting mechanism 46 described above will be briefly described with reference to FIGS. 18A to 18C. 18A to 18C are schematic views for explaining the operation of the boom connecting mechanism 46. FIG. 18A is a schematic view showing an expanded state of the boom connecting mechanism 46 and an engaging state of the pair of boom connecting pins 144a and the pair of first boom pin receiving portions 142b of the intermediate boom element 142. FIG. 18B is a schematic view showing a state in which the boom connecting mechanism 46 is in the process of transitioning from the expanded state to the contracted state. Further, FIG. 18C is a schematic view showing a reduced state of the boom connecting mechanism 46 and a detached state of the pair of boom connecting pins 144a and the pair of first boom pin receiving portions 142b of the intermediate boom element 142.
[0152]
　The boom connecting mechanism 46 as described above makes a state transition between an expanded state (see FIG. 18A) and a reduced state (see FIG. 18C) based on the power (that is, rotational motion) of the electric motor 41. Hereinafter, with reference to FIGS. 18A to 18C, the operation of each part when the boom connecting mechanism 46 transitions from the expanded state to the contracted state will be described. In addition, in FIGS. 18A to 18C, the first missing tooth gear 450 and the second missing tooth gear 460 are schematically shown as an integrated missing tooth gear. Hereinafter, for convenience of explanation, this integrated missing tooth gear will be described as a second missing tooth gear 460. Further, in FIGS. 18A to 18C, the lock mechanism 47 described later is omitted.
[0153]
　At the time of the state transition from the expanded state to the contracted state, the power (that is, rotary motion) of the electric motor 41 is the second missing tooth gear 460 → one second rack bar 461a → synchronous gear 462 → the other second rack bar. It is transmitted by the route of 461b.
[0154]
　First, in the path, based on the power of the electric motor 41, the second toothless gear 460 is forward in the rotational direction (in FIG. 8 arrow F 2 rotates in the direction indicated by).
[0155]
　When the second missing tooth gear 460 rotates in the front side in the rotation direction, one of the second rack bars 461a is displaced in the Y direction + side (right side in FIGS. 18A to 18C) according to the rotation.
[0156]
　Then, the synchronous gear 462 rotates according to the displacement of one of the second rack bars 461a in the Y direction + side. Then, in response to the rotation of the synchronous gear 462, the other second rack bar 461b is displaced in the Y direction − side (left side in FIGS. 18A to 18C).
[0157]
　When the pair of second rack bars 461a and 461b are engaged with the pair of boom connecting pins 144a and the state transitions from the expanded state to the contracted state, the pair of boom connecting pins 144a becomes the pair of first of the intermediate boom elements 142. It separates from the boom pin receiving portion 142b (see FIG. 18C).
[0158]
　In the position information detection device 44, the pair of boom connecting pins 144a is separated from the pair of first boom pin receiving portions 142b of the intermediate boom element 142 and reaches a predetermined position (for example, the position shown in FIGS. 2B and 18C). Detects displacement. Then, based on this detection result, the control unit 44b stops the operation of the electric motor 41.
[0159]
　The state transition from the reduced state to the expanded state (that is, the state transition from FIG. 18C to FIG. 18A) is performed by the second urging mechanism 463 when the brake mechanism 42 is released in the non-energized state of the electric motor 41. It is done automatically based on the urging force. At this time, the pair of boom connecting pins 144a are displaced in a direction away from each other. In the position information detection device 44, the pair of boom connecting pins 144a engages with the pair of first boom pin receiving portions 142b of the intermediate boom element 142, and the position information detection device 44 has a predetermined position (for example, the position shown in FIGS. 2A and 18A). Detects displacement to. The detection result is used to control the next operation of the actuator 2.
[0160]
　Further, in the case of the present embodiment, in one boom element (for example, the tip boom element 141), it is prevented that the cylinder connecting pin is pulled out and the boom connecting pin is pulled out at the same time.
[0161]
　Therefore, the state transition of the cylinder connecting mechanism 45 and the state transition of the boom connecting mechanism 46 are prevented from occurring at the same time.
[0162]
　Specifically, in the cylinder connecting mechanism 45, when the first tooth portion 450a of the first missing tooth gear 450 meshes with the first rack tooth portion 451a of the first rack bar 451, the boom connecting mechanism 46 The second tooth portion 460a of the second missing tooth gear 460 does not mesh with the drive rack tooth portion 461c of one of the second rack bars 461a.
[0163]
　On the contrary, in the boom connecting mechanism 46, when the second tooth portion 460a of the second missing tooth gear 460 meshes with the driving rack tooth portion 461c of one of the second rack bars 461a, the cylinder connecting mechanism In No. 45, the first tooth portion 450a of the first missing tooth gear 450 does not mesh with the first rack tooth portion 451a of the first rack bar 451.
[0164]
　[About the lock mechanism] As described
　above, the actuator 2 according to the present embodiment has a cylinder connection in one boom element (for example, the tip boom element 141) based on the configuration of the boom connection mechanism 46 and the cylinder connection mechanism 45. The pin-pulled state and the boom connecting pin-pulled state are not realized at the same time. Such a configuration prevents the boom connecting mechanism 46 and the cylinder connecting mechanism 45 from operating at the same time based on the power of the electric motor 41.
[0165]
　With such a configuration, the actuator 2 according to the present embodiment has an external force other than the electric motor 41 on the cylinder connecting mechanism 45 (for example, the first rack bar 451) or the boom connecting mechanism 46 (for example, the second rack bar 461a). A lock mechanism 47 is provided to prevent the cylinder connecting mechanism 45 and the boom connecting mechanism 46 from transitioning to each other at the same time when
[0166]
　Such a lock mechanism 47 prevents the operation of the other coupling mechanism while one of the boom coupling mechanism 46 and the cylinder coupling mechanism 45 is operating. Hereinafter, the specific structure of the lock mechanism 47 will be described with reference to FIGS. 14A to 14D. 14A to 14D are schematic views for explaining the structure of the lock mechanism 47.
[0167]
　Further, in FIGS. 14A to 14D, an integrated missing gear 49 (also referred to as a switch gear) in which the first missing gear 450 of the cylinder connecting mechanism 45 and the second missing gear 460 of the boom connecting mechanism 46 are integrally formed. ). Such an integrated missing tooth gear 49 has a substantially circular ring plate shape, and has a tooth portion 49a on a part of the outer peripheral surface. The structure of the other parts is the same as the structure of the present embodiment described above.
[0168]
　The lock mechanism 47 includes a first convex portion 470, a second convex portion 471, and a cam member 472 (also referred to as a lock-side rotating member).
[0169]
　The first convex portion 470 is integrally provided with the first rack bar 451 of the cylinder connecting mechanism 45. Specifically, the first convex portion 470 is provided at a position adjacent to the first rack tooth portion 451a of the first rack bar 451.
[0170]
　The second convex portion 471 is integrally provided with one second rack bar 461a of the boom connecting mechanism 46. Specifically, the second convex portion 471 is provided at a position adjacent to the drive rack tooth portion 461c of one of the second rack bars 461a.
[0171]
　The cam member 472 is a plate-shaped member having a substantially crescent shape. Such a cam member 472 has a first cam receiving portion 472a at one end in the circumferential direction. On the other hand, the cam member 472 has a second cam receiving portion 472b at the other end in the circumferential direction.
[0172]
　For example, the cam member 472 is externally fitted and fixed at a position shifted in the X direction from the position where the integrated missing tooth gear 49 is externally fixed on the transmission shaft 432. In the case of the present embodiment, the cam member 472 is externally fitted and fixed between the first missing tooth gear 450 and the second missing tooth gear 460. That is, the cam member 472 and the integrated missing tooth gear 49 are provided coaxially. Such a cam member 472 rotates together with the transmission shaft 432. Therefore, the cam member 472 rotates around the central axis of the transmission shaft 432 together with the integrated missing tooth gear 49.
[0173]
　The cam member 472 may be integrated with the integrated missing tooth gear 49. Further, in the case of the present embodiment, the cam member 472 may be integrated with at least one of the first missing gear 450 and the second missing gear 460.
[0174]
　As shown in FIGS. 14B to 14D and 15A, the tooth portion 49a of the integrated missing tooth gear 49 (also the second tooth portion 460a of the second missing tooth gear 460) is one of the second rack bars. The first cam receiving portion 472a of the cam member 472 is located on the + side in the Y direction with respect to the first convex portion 470 in a state of being meshed with the drive rack tooth portion 461c of the 461a. At this time, the tooth portion 49a of the integrated missing gear 49 does not mesh with the first rack tooth portion 451a of the first rack bar 451.
[0175]
　In this state, the first cam receiving portion 472a and the first convex portion 470 face each other with a slight gap in the Y direction (see FIG. 15A). Thus, the first rack bar 451 Y-direction + side of the external force (arrow F in Figure 15A a , even when the direction of the force indicated by) is applied, the displacement in the Y-direction + side of the first rack bar 451 is prevented The arrow.
[0176]
　Specifically, the external force F in the Y-direction + side to the first rack bar 451 a when the applied first rack bar 451, the Y-direction + side from the position shown by the two-dot chain line in FIG. 15A to the position indicated by a solid line Displace. In this state, the first convex portion 470 comes into contact with the first cam receiving portion 472a, and the displacement of the first rack bar 451 in the Y direction + side is prevented.
[0177]
　In the state shown in FIGS. 14B to 14D, the outer peripheral surface of the cam member 472 and the first convex portion 470 face each other with a slight gap in the Y direction. As a result, even when an external force on the Y direction + side is applied to the first rack bar 451, displacement of the first rack bar 451 in the Y direction + side is prevented.
[0178]
　On the other hand, as shown in FIG. 15B, the tooth portion 49a of the integrated missing tooth gear 49 (also the first tooth portion 450a of the first missing tooth gear 450 in the cylinder connecting mechanism 45) is the first rack bar 451. In the state of meshing with the first rack tooth portion 451a, the second cam receiving portion 472b of the cam member 472 is located on the + side in the Y direction with respect to the second convex portion 471.
[0179]
　In this state (the state shown by the alternate long and short dash line in FIG. 15B), the second cam receiving portion 472b and the second convex portion 471 face each other with a slight gap in the Y direction. Thus, (arrow F in Figure 15B one second rack bar 461a in the Y-direction + side of the external force b even when the applied), Specifically, when an external force F b on the + side in the Y direction is applied to one second rack bar 461a, one second rack bar 461a Y from the position shown by the alternate long and short dash line to the position shown by the solid line in FIG. 15B. Displace to the + side. In this state, the second convex portion 471 comes into contact with the second cam receiving portion 472b, and the displacement of one of the second rack bars 461a in the Y direction + side is prevented.
[0180]
　[1.2 Operation of Actuator]
　Hereinafter, the expansion / contraction operation of the telescopic boom 14 and the operation of the actuator 2 during the expansion / contraction operation will be described with reference to FIGS. 2 and 16. FIG. 16 is a timing chart of the telescopic boom 14 when the tip boom element 141 is extended.
[0181]
　Hereinafter, only the extension operation of the tip boom element 141 in the telescopic boom 14 will be described. The contraction operation of the tip boom element 141 is the reverse of the procedure of the expansion / contraction operation described below.
[0182]
　In the following description, the state transition between the expanded state and the contracted state of the cylinder connecting mechanism 45 and the boom connecting mechanism 46 is as described above. Therefore, detailed description of the state transition of the cylinder connecting mechanism 45 and the boom connecting mechanism 46 will be omitted.
[0183]
　Further, the ON / OFF switching of the electric motor 41 and the ON / OFF switching of the brake mechanism 42 are controlled by the control unit based on the output of the position information detection device 44 described above.
[0184]
　FIG. 2A shows the contracted state of the telescopic boom 14. In this state, the tip boom element 141 is connected to the intermediate boom element 142 via the boom connecting pin 144a. Therefore, the tip boom element 141 cannot be displaced in the longitudinal direction (left-right direction in FIG. 2) with respect to the intermediate boom element 142.
[0185]
　Further, in FIG. 2A, the tip portions of the cylinder connecting pins 454a and 454b engage with the pair of cylinder pin receiving portions 141a of the tip boom element 141. That is, the tip boom element 141 and the cylinder member 32 are in a connected state.
[0186]
　In the state of FIG. 2A, the state of each member is as follows (see T0 to T1 of FIG. 16).
　Brake mechanism 42: OFF
　electric motor 41: OFF
　cylinder connecting mechanism 45: Extended state
　boom connecting mechanism 46: Extended state
　cylinder connecting pin 454a, 454b: Entered state
　Boom connecting pin 144a: Entered state
[0187]
　Next, in the state shown in FIG. 2A, the electric motor 41 is rotated in the normal direction (rotated in the first direction which is the clockwise direction when viewed from the tip side of the output shaft), and a pair is formed by the boom connecting mechanism 46 of the actuator 2. The boom connecting pin 144a is displaced in a direction away from the pair of first boom pin receiving portions 142b of the intermediate boom element 142. At this time, the boom connecting mechanism 46 makes a state transition from the expanded state to the contracted state.
[0188]
　The state of each member at the time of the state transition from FIG. 2A to FIG. 2B is as follows (see T1 to T2 in FIG. 16).
　Brake mechanism 42: OFF
　electric motor 41: ON
　cylinder connecting mechanism 45: Expanded state
　boom connecting mechanism 46: Expanded state → reduced state
　Cylinder connecting pins 454a, 454b: On state
　Boom connecting pin 144a: On state → unplugged state
[0189]
　Along with the above-mentioned state transition, the pair of boom connecting pins 144a and the pair of first boom pin receiving portions 142b of the intermediate boom element 142 are disengaged (see FIG. 2B). After that, the brake mechanism 42 is turned on and the electric motor 41 is turned off.
[0190]
　The timing of turning off the electric motor 41 and the timing of turning on the brake mechanism 42 are appropriately controlled by the control unit. For example, although not shown, the electric motor 41 is turned off after the brake mechanism 42 is turned on.
[0191]
　In the state of FIG. 2B, the state of each member is as follows (see T2 of FIG. 16).
　Brake mechanism 42: ON
　electric motor 41: OFF
　cylinder connecting mechanism 45: Extended state
　boom connecting mechanism 46: Reduced state
　Cylinder connecting pins 454a, 454b: On state
　Boom connecting pin 144a: Unplugged state
[0192]
　Next, in the state shown in FIG. 2B, pressure oil is supplied to the hydraulic chamber on the extension side of the telescopic cylinder 3 of the actuator 2. Then, the cylinder member 32 is displaced in the extension direction (left side in FIG. 2).
[0193]
　With the displacement of the cylinder member 32 as described above, the tip boom element 141 is displaced in the extension direction (see FIG. 2C). At this time, as for the state of each part, the state of T2 in FIG. 16 is maintained until T3.
[0194]
　Next, the brake mechanism 42 is released in the state shown in FIG. 2C. Then, based on the urging force of the second urging mechanism 463, the boom connecting mechanism 46 displaces the pair of boom connecting pins 144a in the direction of engaging the pair of second boom pin receiving portions 142c of the intermediate boom element 142. At this time, the boom connecting mechanism 46 makes a state transition (that is, automatic return) from the contracted state to the expanded state.
[0195]
　The state of each member at the time of the state transition from FIG. 2C to FIG. 2D is as follows (see T3 to T4 in FIG. 16).
　Brake mechanism 42: OFF
　electric motor 41: OFF
　cylinder connecting mechanism 45: Expanded state
　Boom connecting mechanism 46: Reduced state → Expanded state
　Cylinder connecting pins 454a, 454b: On state
　Boom connecting pin 144a: Unplugged state → Entered state
[0196]
　Then, as shown in FIG. 2D, the pair of boom connecting pins 144a engage with the pair of second boom pin receiving portions 142c of the intermediate boom element 142.
[0197]
　The state of each member in the state shown in FIG. 2D is as follows (see T4 in FIG. 16).
　Brake mechanism 42: OFF
　electric motor 41: ON
　cylinder connecting mechanism 45: Expanded
　boom connecting mechanism 46: Expanded
　cylinder connecting pin 454a, 454b: Entered
　boom connecting pin 144a: Entered
[0198]
　Further, in the state shown in FIG. 2D, the electric motor 41 is reversed (rotated in the second direction which is the counterclockwise direction when viewed from the tip side of the output shaft), and the cylinder connecting mechanism 45 causes a pair of cylinder connecting pins. The 454a and 454b are displaced in a direction away from the pair of cylinder pin receiving portions 141a of the tip boom element 141. At this time, the cylinder connecting mechanism 45 makes a state transition from the expanded state to the reduced state.
[0199]
　The state of each member at the time of the state transition from FIG. 2D to FIG. 2E is as follows (see T4 to T5 in FIG. 16).
　Brake mechanism 42: OFF
　electric motor 41: ON
　cylinder connecting mechanism 45: Expanded state → reduced state
　Boom connecting mechanism 46: Expanded state
　Cylinder connecting pin 454a, 454b: On state → Unplugged state
　Boom connecting pin 144a: On state
[0200]
　Then, as shown in FIG. 2E, the engagement between the tip portions of the pair of cylinder connecting pins 454a and 454b and the pair of cylinder pin receiving portions 141a of the tip boom element 141 is released. After that, the brake mechanism 42 is turned on and the electric motor 41 is turned off.

The scope of the claims
[Claim 1]
　A telescopic boom having an inner boom element and an outer boom element that are stretchably overlapped,
　a telescopic actuator that displaces one of the inner boom element and the outer boom element in the telescopic direction, and the
　telescopic actuator. A first connecting member that is detachably connected to the one
　boom element, a second connecting member that detachably connects the inner boom element and the outer boom element, and
　an electric drive provided in the telescopic actuator.
　By displaces one of the first connecting member and the second connecting member based on the power of the source and the electric drive source, the members connected by the one connecting member are connected to each other. A 　crane
　comprising a first coupling mechanism for switching between a state and a non-coupled state, and a position information detecting device for detecting information regarding the position of one of the connecting members based on the output of the electrical drive source
.
[Claim 2]
　The crane according to claim 1, wherein the electric drive source is a single electric drive source.
[Claim 3]
　By displace the other connecting member of the first connecting member and the second connecting member based on the power of the electric drive source, the members connected by the other connecting member are not connected to each other.
　Claim 1 or 2 , further comprising a second coupling mechanism for switching between coupling states, wherein the position information detecting device detects information about the position of the other coupling member based on the output of the electrical drive source. Described crane.
[Claim 4]

　To maintain the state of the first connecting mechanism and the second connecting mechanism in the stopped state of the 　speed reducer that decelerates the power of the electric drive source and transmits it to the first connecting mechanism. The crane according to claim 3, further comprising the brake mechanism of the above.
[Claim 5]
　A claim that the brake mechanism allows rotation of an electric drive source based on the external force when an external force of a predetermined magnitude or more acts on the first connecting mechanism or the second connecting mechanism during braking. The crane according to 4.
[Claim 6]
　The crane according to claim 4 or 5, wherein the brake mechanism is arranged closer to the electric drive source side than the speed reducer.
[Claim 7]
　The crane according to any one of claims 4 to 6, wherein the electric drive source, the speed reducer, and the brake mechanism are provided coaxially with the output shaft of the electric drive source.
[Claim 8]
　The crane according to any one of claims 4 to 7, wherein the position information detecting device detects information about the position based on the power of the electric drive source that has not been decelerated by the speed reducer.
[Claim 9]
　The crane according to any one of claims 4 to 7, wherein the position information detecting device detects information about the position based on the power of the electric drive source decelerated by the speed reducer.
[Claim 10]
　3. The third aspect of the present invention, further comprising a switch gear that selectively transmits the power of the electric drive source to one of the first coupling mechanism and the second coupling mechanism. crane.
[Claim 11]
　The switch gear prevents the operation of the other coupling mechanism of the first coupling mechanism and the second coupling mechanism in a state where the power of the electric drive source is transmitted to the one coupling mechanism. The crane according to claim 10, further comprising a locking mechanism.
[Claim 12]
　The first coupling mechanism causes the first coupling mechanism to undergo a state transition so that the members connected by the one connecting member are in a connected state when the electrical drive source is stopped. a mechanism,
　the second connecting mechanism, in a state in which the electric driving source is stopped, as members to each other which are connected by the other connecting member is a connecting state, thereby the state transition the second connecting mechanism The crane according to claim 3, further comprising a second urging mechanism.
[Claim 13]
　The crane according to any one of claims 1 to 12, wherein the position information detecting device is provided on an output shaft of the electric drive source or a rotating member that rotates according to the rotation of the output shaft. ..
[Claim 14]
　The crane according to claim 13, wherein the position information detecting device includes a proximity sensor.
[Claim 15]
　The crane according to claim 13, wherein the position information detecting device includes a limit switch.
[Claim 16]
　The crane according to claim 13, wherein the position information detecting device includes an encoder.