[0001]The present invention relates to a working machine provided with a telescopic boom.
Background technology
[0002]Patent Document 1 discloses a telescopic boom in which a plurality of boom elements are stacked in a nested manner (also referred to as a telescopic shape), and a mobile crane provided with a hydraulic telescopic cylinder for extending the telescopic boom. There is.
[0003]
　The telescopic boom has a boom connecting pin that connects adjacent and overlapping boom elements. The boom element (hereinafter referred to as a movable boom element) to which the connection by the boom connecting pin is disconnected becomes movable 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 movable boom element via a cylinder connecting pin. When the cylinder member moves in the expansion / contraction direction in this state, the movable boom element moves 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 for moving the boom connecting pin, a hydraulic actuator for moving the cylinder connecting pin, and a hydraulic circuit for supplying pressure oil to each of these actuators. Such a hydraulic circuit is provided, for example, around a telescopic boom. This may reduce the degree of freedom in design around the telescopic boom.
[0007]
　An object of the present invention is to provide a working machine capable of increasing the degree of freedom in design around a telescopic boom.
Means to solve problems
[0008]
　The working machine according to the present invention has
　an actuator that expands and contracts a telescopic boom,
　an electric drive source that is provided in the actuator and is driven by power supply from a power source, and
　an operation that operates based on the power of the electric drive source. The drive state that allows the power supply from the
　power supply to the electric drive source and drives the electric drive source, and the braking force that is applied to the electric drive source by stopping the power supply from the power supply to the electric drive source. It includes an electric circuit capable of switching between the generated braking state and
　a control unit for controlling switching between the driving state and the braking state.
The invention's effect
[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 diagram of a mobile crane according to an 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] 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 taken along the line A1 of FIG.
FIG. 7 is a perspective view of a pin moving module in a state where the boom connecting pin is held.
FIG. 8 is a front view of a pin moving module in an expanded state and holding a boom connecting pin.
FIG. 9 is a view taken along the line A2 of FIG.
FIG. 10 is a view taken along the line A3 of FIG.
FIG. 11 is a view taken along the line A4 of FIG.
FIG. 12 is a front view of a pin moving module in which the boom coupling mechanism is in the reduced state and the cylinder coupling mechanism is in the expanded state.
FIG. 13 is a front view of a pin moving 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. 16A is a circuit diagram of an electric circuit in a non-energized state.
FIG. 16B is a circuit diagram of an electric circuit in the first drive state.
FIG. 16C is a circuit diagram of an electric circuit in a second drive state.
FIG. 16D is a circuit diagram of an electric circuit in a braking state.
FIG. 17 is a timing chart of the telescopic boom during the extension operation.
FIG. 18A is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 18B is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 18C is a schematic diagram for explaining the operation of the cylinder connecting mechanism.
FIG. 19A is a schematic diagram for explaining the operation of the boom coupling mechanism.
FIG. 19B is a schematic diagram for explaining the operation of the boom coupling mechanism.
[FIG. 19C] FIG. 19C is a schematic diagram for explaining the operation of the boom coupling mechanism.
Embodiment for carrying out the invention
[0011]
　Hereinafter, an example of the embodiment according to the present invention will be described in detail with reference to the drawings. The crane according to the embodiment described later is an example of the working machine according to the present invention, and the present invention is not limited to the embodiment described later.
[0012]
　[Embodiment]
　FIG. 1 is a schematic diagram of a mobile crane 1 (rough terrain crane in the case of illustration) according to the present embodiment. The mobile crane 1 corresponds to an example of a working machine.
[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 working machine according to the present invention is not limited to the mobile crane, and can be applied to other working vehicles having a telescopic boom (for example, a crane, an aerial work platform).
[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]
　
　As shown in FIG. 1, the mobile crane 1 includes a traveling body 10, an outrigger 11, a swivel base 12, a telescopic boom 14, an actuator 2 (omitted in FIG. 1), and electricity. It has a circuit 6 (see FIGS. 16A to 16D), an undulating cylinder 15, a wire 16, and a hook 17.
[0016]
　The traveling body 10 has a plurality of wheels 101. Outriggers 11 are provided at the four corners of the traveling body 10. The swivel table 12 is provided on the upper part of the traveling body 10 so as to be swivelable. The base end of the telescopic boom 14 is fixed to the swivel base 12. The actuator 2 expands and contracts the telescopic boom 14. The undulating cylinder 15 undulates the telescopic boom 14. The wire 16 hangs down from the tip of the telescopic boom 14. The hook 17 is provided at the tip of the wire 16.
[0017]
　
　Next, the telescopic boom 14 will be described with reference to FIGS. 1 and 2A to 2E. 2A to 2E are schematic views for explaining the structure and expansion / contraction operation of the telescopic boom 14.
[0018]
　FIG. 1 shows a telescopic boom 14 in an extended state. 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.
[0019]
　The telescopic boom 14 is composed of a plurality of boom elements. Each of the boom elements is tubular. The boom elements are telescopically combined with each other. 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.
[0020]
　In the case of the present embodiment, the tip boom element 141 and the intermediate boom element 142 correspond to an example of the first boom element that can move in the expansion / contraction direction. When the tip boom element 141 moves in the expansion / contraction direction with respect to the intermediate boom element 142, the tip boom element 141 corresponds to an example of the first boom element, and the intermediate boom element 142 corresponds to an example of the second boom element. do. Further, when the intermediate boom element 142 moves in the expansion / contraction direction with respect to the proximal boom element 143, the intermediate boom element 142 corresponds to an example of the first boom element, and the proximal boom element 143 is the second boom. Corresponds to an example of an element. The base end boom element 143 is restricted from moving in the expansion / contraction direction.
[0021]
　The telescopic boom 14 expands in order from the boom element (that is, the tip boom element 141) arranged inside, so that the state transitions from the contracted state shown in FIG. 2A to the extended state shown in FIG.
[0022]
　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. The number of intermediate boom elements may be plural.
[0023]
　The structure of the telescopic boom 14 is almost the same as the structure of the telescopic boom known conventionally, but for convenience of explanation regarding the structure and operation of the actuator 2 described later, the tip boom element 141 and the intermediate boom are described below. The structure of the element 142 will be described.
[0024]
　
　The tip boom element 141 has a tubular shape as shown in FIGS. 2A to 2E. The tip boom element 141 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.
[0025]
　The pair of cylinder pin receiving portions 141a are provided 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 detached 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, either the pair of cylinder pin receiving portions 141a is engaged with the pair of cylinder connecting pins 454a and 454b, or the pair of cylinder pin receiving portions 141a is disengaged with the pair of cylinder connecting pins 454a and 454b. It can take one of the states.
[0026]
　The cylinder connecting pins 454a and 454b move 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 engaged with the pair of cylinder pin receiving portions 141a, the tip boom element 141 can move in the expansion / contraction direction together with the cylinder member 32.
[0027]
　The pair of boom pin receiving portions 141b are provided 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). That is, the pair of boom pin receiving portions 141b takes either an engaged state of engaging with the pair of boom connecting pins 144a or a disengaged state of being disengaged with the pair of boom connecting pins 144a. obtain.
[0028]
　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 move in their own axial direction based on the operation of the boom connecting mechanism 46 included in the actuator 2. The pair of boom connecting pins 144a may be regarded as constituent members of the boom connecting mechanism 46.
[0029]
　With the tip boom element 141 and the intermediate boom element 142 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 will be described. The boom connecting pin 144a is inserted so as to be bridged to the second boom pin receiving portion 142c.
[0030]
　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 is prohibited from moving in the expansion / contraction direction with respect to the intermediate boom element 142.
[0031]
　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 move in the expansion / contraction direction with respect to the intermediate boom element 142.
[0032]
　
　The intermediate boom element 142 has a tubular shape as shown in FIGS. 2A to 2E. The intermediate boom element 142 has an internal space that can accommodate 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, a pair of second boom pin receiving portions 142c, and a pair of third boom pin receiving portions 142d at the base end portion.
[0033]
　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.
[0034]
　The pair of third boom pin receiving portions 142d are provided coaxially with each other on the proximal end side of the pair of first boom pin receiving portions 142b. A pair of boom connecting pins 144b are inserted into each of the pair of third boom pin receiving portions 142d. The pair of boom connecting pins 144b connects the intermediate boom element 142 and the proximal boom element 143.
[0035]
　The pair of second boom pin receiving portions 142c are provided coaxially with each other at the tip end portion of the intermediate boom element 142. A pair of boom connecting pins 144a are inserted into each of the pair of second boom pin receiving portions 142c.
[0036]
　
　Hereinafter, the actuator 2 will be described with reference to FIGS. 3A to 19C. The actuator 2 is an actuator that expands and contracts the telescopic boom 14 (see FIGS. 1 and 2A to 2E) as described above.
[0037]
　The actuator 2 has a telescopic cylinder 3 and a pin moving 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]
　
　The telescopic cylinder 3 has a rod member 31 (also referred to as a fixed side member; see FIGS. 2A to 2E) and a cylinder member 32 (also referred to as a movable side member). The telescopic cylinder 3 moves a 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 structure of the telescopic cylinder 3 is almost the same as the structure of the telescopic cylinder known conventionally, detailed description thereof will be omitted.
[0039]
　
　The pin movement module 4 has 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. 7).
[0040]
　Hereinafter, each member constituting the actuator 2 will be described with reference to the 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. The X direction-side is also referred to as a contraction direction in the expansion / contraction direction. Further, the Z direction coincides with the vertical direction of the mobile crane 1 in a state where the undulation angle of the telescopic boom 14 is zero (also referred to as an undulating state of the telescopic boom 14), for example. The Y direction coincides with the vehicle width direction of the mobile crane 1, for example, in a state where the telescopic boom 14 faces forward. 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.
[0042]
　
　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. The housing 40 supports the electric motor 41 via the transmission mechanism 43. Further, the housing 40 also supports the brake mechanism 42 described later. Such a housing 40 unitizes each of the above-mentioned elements. Such a configuration contributes to the miniaturization of the pin movement 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 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).
[0045]
　The first housing element 400 has through holes 400a and 400b (see FIGS. 3B and 7) on the side walls on both sides in the Y direction. A pair of cylinder connecting pins 454a and 454b of the cylinder connecting mechanism 45 are inserted into the through holes 400a and 400b, respectively.
[0046]
　The second housing element 401 is provided on the + side in the Z direction of the first housing element 400. The second housing element 401 accommodates the 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 described later is inserted through the second housing element 401 in the X direction.
[0047]
　The second housing element 401 has through holes 401a and 401b (see FIGS. 3B and 7) on the side walls on both sides in the Y direction. 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]
　
　The electric motor 41 corresponds to an example of an electric drive source, and is supported by a housing 40 via a speed reducer 431 of a 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 contributes to the miniaturization of the pin movement 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 supply device 61 (see FIGS. 16A to 16D) provided on the swivel base 12 via a power supply cable. Further, the electric motor 41 is connected to, for example, a control unit 44b (see FIG. 1) provided on the swivel table 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]
　Further, the electric motor 41 has 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 movement module 4. When the manual operation unit 410 is turned 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 movement module 4 changes.
[0052]
　The number of electric motors may be one or a plurality (for example, two). When there is one electric motor, the cylinder connecting mechanism 45 and the boom connecting mechanism 46 are operated by one electric motor 41 as in the present embodiment. When there are a plurality of (for example, two) electric motors, the cylinder connecting mechanism 45 is operated by the first electric motor (not shown), and the boom connecting mechanism 46 is operated by the second electric motor (not shown). It's okay.
[0053]
　In the case of this embodiment, the electric drive source is the electric motor 41 described above. However, the electric drive source is not limited to the electric motor. For example, the electrical drive source may be various drive sources that generate a drive force based on energization from a power source.
[0054]
　
　The brake mechanism 42 applies a braking force to the electric motor 41. The brake mechanism 42 prevents the output shaft of the electric motor 41 from rotating when the electric motor 41 is stopped. As a result, the state of the pin moving module 4 is maintained in the stopped state of the electric motor 41.
[0055]
　Further, the brake mechanism 42 may allow 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 contributes to prevention of damage to the electric motor 41 constituting the actuator 2 and each gear. When such a configuration is adopted, for example, a friction brake can be adopted as the brake mechanism 42.
[0056]
　Specifically, the brake mechanism 42 operates in the reduced state of the cylinder connecting mechanism 45 or the 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.
[0057]
　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 centered on the electric motor 41). (See FIG. 3B).
[0058]
　Such an arrangement contributes to the miniaturization of the pin movement module 4 in the Y direction and the Z direction. The front stage means the upstream side (the side close 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.
[0059]
　The brake torque required to maintain the stopped state of the electric motor 41 is such that the brake mechanism 42 is arranged in front of the transmission mechanism 43, and the brake mechanism 42 is the transmission mechanism 43 (reducer 431 described later). It is smaller than the configuration placed later than. For this reason, the configuration in which the brake mechanism 42 is arranged in front of the transmission mechanism 43 contributes to the miniaturization of the brake mechanism 42.
[0060]
　The brake mechanism 42 may be various brake devices such as a mechanical type or an electromagnetic type. Further, the position of the brake mechanism 42 is not limited to the position of the present embodiment.
[0061]
　
　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).
[0062]
　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. The speed reducer 431 is provided coaxially with the output shaft of the electric motor 41. Such an arrangement contributes to the miniaturization of the pin movement module 4 in the Y direction and the Z direction.
[0063]
　The end of the transmission shaft 432 on the X-direction side 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 extends in the X direction and is inserted into the housing 40 (specifically, the second housing element 401). The transmission shaft 432 may be integrated with the output shaft of the speed reducer 431.
[0064]
　The end of the transmission shaft 432 on the + side in the X direction protrudes from the housing 40 on the + side in the X direction. A position information detecting device 44, which will be described later, is provided at the end of the transmission shaft 432 on the + side in the X direction.
[0065]
　
　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) based on the output of the electric motor 41 (for example, rotation of the output shaft). It may be pin 144b. The same shall apply hereinafter) to detect information about the position. The information regarding the position may be, for example, the amount of movement of the pair of cylinder connecting pins 454a, 454b or the pair of boom connecting pins 144a from the reference position (positions shown in FIGS. 18A and 19A). The positions of the pair of cylinder connecting pins 454a and 454b shown in FIGS. 18A and 19A are defined as the reference positions of the cylinder connecting pins 454a and 454b. Further, the positions of the pair of boom connecting pins 144a shown in FIGS. 18A and 19A are defined as the reference positions of the boom connecting pins 144a.
[0066]
　Specifically, the position information detecting device 44 engages with a pair of cylinder connecting pins 454a and 454b and a pair of cylinder pin receiving portions 141a of the boom element (for example, the tip boom element 141) (for example, FIG. 2A). Information regarding the positions of the pair of cylinder connecting pins 454a and 454b in the state shown in (1) or the detached state (state shown in FIG. 2E) is detected.
[0067]
　Further, the position information detecting device 44 may be a pair of boom connecting pins 144a and a pair of first boom pin receiving portions 142b (pair of second boom pin receiving portions 142c) of the boom element (for example, the intermediate boom element 142). The same) is detected (for example, the state shown in FIGS. 2A and 2D) or the disengaged state (for example, the state shown in FIG. 2B) regarding the position of the pair of boom connecting pins 144a.
[0068]
　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.
[0069]
　The position information detection device 44 has a detection unit 44a and a control unit 44b (see FIGS. 18A and 18A).
[0070]
　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 amount of rotation of the output shaft of the electric motor 41. The output method of the rotary encoder is not particularly limited, and an incremental method that outputs a pulse signal (relative angle signal) according to the amount of rotation (rotation angle) from the measurement start position may be used, or an absolute angle with respect to the reference point. An absolute method that outputs a code signal (absolute angle signal) corresponding to the position may be used.
[0071]
　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.
[0072]
　The detection unit 44a may be provided on the output shaft of the electric motor 41. Further, the detection unit 44a may be provided on a rotating member (for example, a rotating shaft, a gear, etc.) that rotates together with the output shaft of the electric motor 41. Specifically, in the case of the present embodiment, the detection unit 44a is provided at the end of the transmission shaft 432 on the + side in the X direction. In other words, in the case of the present embodiment, the detection unit 44a is provided at a stage after the speed reducer 431 (that is, on the + side in the X direction).
[0073]
　In the case of the present embodiment, the detection unit 44a outputs information according to the amount of rotation of the transmission shaft 432. 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 (rotational 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 output information of the detection unit 44a is obtained. It is also information according to the rotation amount of the first missing tooth gear 450 and the second missing tooth gear 460.
[0074]
　The detection unit 44a having the above configuration sends the detection value to the control unit 44b. The control unit 44b that has acquired the information calculates information regarding the position of the pair of cylinder connecting pins 454a and 454b or the pair of boom connecting pins 144a based on the acquired information. Then, the control unit 44b controls the electric motor 41 based on the calculation result.
[0075]
　The control unit 44b is an in-vehicle computer composed of, for example, an input terminal, an output terminal, a CPU, and a memory. The control unit 44b calculates information regarding the position of the pair of cylinder connecting pins 454a and 454b or the boom connecting pin 144a based on the output of the detection unit 44a.
[0076]
　Specifically, for example, the control unit 44b has information regarding 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 movement from the reference position). Information about the above position is calculated using data showing the correlation (table, map, etc.).
[0077]
　When the output of the detection unit 44a is a code signal, data showing the correlation between each code signal and the amount of movement from the reference position in the pair of cylinder connecting pins 454a and 454b and the pair of boom connecting pins 144a (table). , Map, etc.) to calculate information about the above location.
[0078]
　The control unit 44b as described above is provided on the swivel table 12. However, the position of the control unit 44b is not limited to the swivel table 12. The control unit 44b may be provided, for example, in a case (not shown) in which the detection unit 44a is arranged.
[0079]
　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 resolution of the detection unit 44a is higher in the configuration in which the detection unit 44a is arranged in the front stage of the speed reducer 431 than in the configuration in which the detection unit 44a is arranged in the rear stage of the speed reducer 431.
[0080] [0080]
　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 limit switches are 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 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.
[0081]
　
　The cylinder connecting mechanism 45 corresponds to an example of an operating unit, operates based on the power of the electric motor 41 (that is, rotary motion), and operates in an expanded state (also referred to as a first state, FIGS. 8 and 12). (See) and the reduced state (also referred to as the second state; see FIG. 13).
[0082]
　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 with each other (also referred to as a cylinder pin inserted state). Will be. In the engaged state, the boom element and the cylinder member 32 are in a connected state.
[0083]
　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 FIGS. 2A to 2E) are separated from each other (the state shown in FIG. 2E and the cylinder pin is removed). Also called.). In the detached state, the boom element and the cylinder member 32 are not connected.
[0084]
　Hereinafter, a specific configuration of the cylinder connecting mechanism 45 will be described. As shown in FIGS. 9 to 13, the cylinder connecting mechanism 45 includes a first missing gear 450, a first rack bar 451, a first gear mechanism 452, a second gear mechanism 453, and a pair of cylinder connecting pins 454a and 454b. It also has a first urging mechanism 455. Each of the above elements 450, 451 and 452, 453 corresponds to an example of the constituent members of the first drive mechanism.
[0085]
　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.
[0086]
　
　The first missing tooth gear 450 (also referred to as a switch gear) has a substantially annular plate shape. The first missing tooth gear 450 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.
[0087]
　Such a first missing tooth gear 450 constitutes a switchgear together with a second missing tooth gear 460 (see FIG. 8) of the boom connecting mechanism 46. The switchgear selectively transmits the power of the electric motor 41 to one of the cylinder coupling mechanism 45 and the boom coupling mechanism 46.
[0088]
　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 switchgear may be provided independently of the first connecting mechanism and the second connecting mechanism.
[0089]
　In the following description, the first missing gear 450 when the cylinder connecting mechanism 45 transitions from the expanded state (see FIGS. 8, 12, and 18A) to the reduced state (see FIGS. 13 and 18C). The direction of rotation ( direction indicated by arrow F2 in FIGS. 18A to 18C ) is the "front side" in the direction of rotation of the first missing tooth gear 450.
[0090]
　On the other hand, the rotation direction of the first missing tooth gear 450 (the direction indicated by the arrow F1 in FIGS. 18A to 18C) when the state transitions from the reduced state to the expanded state is the rotation direction of the first missing tooth gear 450. Is the "rear side" of.
[0091]
　Of 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).
[0092]
　
　The first rack bar 451 moves 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).
[0093]
　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 moves in the Y direction + side (also referred to as one in the longitudinal direction).
[0094]
　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.
[0095]
　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.
[0096]
　The first rack bar 451 has a first rack tooth portion 451a (see FIG. 8) on a surface close 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.
[0097]
　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.
[0098]
　In the expanded state, when the first missing tooth gear 450 rotates to the front side in the rotation direction, the positioning tooth 450b presses the first end surface 451d to the Y direction + side, and the first rack bar 451 moves to the Y direction + side.
[0099]
　Then, the tooth portion existing on the rear side of the positioning tooth in the rotation direction in the first tooth portion 450a meshes with the first rack tooth portion 451a. As a result, the first rack bar 451 moves in the Y direction + side according to the rotation of the first missing tooth gear 450.
[0100]
　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.
[0101]
　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 described later. On the other hand, the third rack tooth portion 451c meshes with the second gear mechanism 453 described later.
[0102]
　
　The first gear mechanism 452 is composed of a plurality of (three in the case of the present embodiment) gear elements 452a, 452b, 452c (see FIG. 8), each of which is a spur gear. Specifically, the gear element 452a 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 portion of the second rack tooth portion 451b of the first rack bar 451.
[0103]
　The gear element 452b meshes with the gear element 452a and the gear element 452c.
[0104]
　The gear element 452c 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 the pin-side rack tooth portion 454c (see FIG. 8) of one cylinder connecting pin 454a.
[0105]
　
　The second gear mechanism 453 is composed of 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 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.
[0106]
　The gear element 453b meshes with the pin-side rack tooth portion 454d (see FIG. 8) of the gear element 453a and the other cylinder connecting pin 454b described later. In the expanded state, the gear element 453b meshes with the end on the + side in the Y direction of the pin-side rack tooth portion 454d of the other cylinder connecting pin 454b.
[0107]
　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 to each other.
[0108]
　
　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 the side far from each other, and the end portion on the side close to the base end portion.
[0109]
　The pair of cylinder connecting pins 454a and 454b each have 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.
[0110]
　One of the cylinder connecting pins 454a moves 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 moves in the Y direction + side (also referred to as a second direction) when the state transitions from the reduced state to the expanded state. On the other hand, one of the cylinder connecting pins 454a moves in the Y direction-side (also referred to as the first direction) when the state transitions from the expanded state to the contracted state.
[0111]
　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 moves in its own axial direction (that is, in the Y direction) as the gear element 453b in the second gear mechanism 453 rotates.
[0112]
　Specifically, the other cylinder connecting pin 454b moves in the Y direction-side (also referred to as a second direction) when the state transitions from the reduced state to the expanded state. On the other hand, the other cylinder connecting pin 454b moves in the Y direction + side (also referred to as the first direction) 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 move in opposite directions in the Y direction.
[0113]
　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.
[0114]
　
　The first urging mechanism 455 automatically returns the cylinder connecting mechanism 45 to the expanded state when the electric motor 41 is in the non-energized state 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. The first urging mechanism 455 may exert a force directly on the cylinder connecting pins 454a and 454b, or may exert a force via another member. Further, the first urging mechanism 455 may be omitted. In this case, the cylinder connecting mechanism 45 may make a state transition from the reduced state to the expanded state based on the power of the electric motor 41.
[0115]
　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 pair of cylinder connecting pins 454a and 454b toward the tip end side. Each of the pair of coil springs 455a and 455b corresponds to an example of the first urging member.
[0116]
　When the brake mechanism 42 is operating, the cylinder connecting mechanism 45 does not automatically return.
[0117]
　
　Next, the electric circuit 6 will be described with reference to FIGS. 16A to 16D. The electric circuit 6 is a so-called H-bridge circuit. The electric circuit 6 realizes a plurality of states by switching a switch under the control of the control unit 44b. A plurality of states realized by the electric circuit 6 will be described later.
[0118]
　The electric circuit 6 includes a power supply device 61, a first switch 62, a second switch 63, a third switch 64, a fourth switch 65, and an electric motor 41.
[0119]
　The power supply unit 61 is provided, for example, on the swivel table 12 (see FIG. 1).
[0120]
　The first switch 62 is, for example, a transistor. The first switch 62 is provided on the first line 6L1. The first switch 62 is in either an ON state (state shown in FIG. 16B) or an OFF state (state shown in FIGS. 16A, 16C, and 16D) under the control of the control unit 44b (see FIG. 1). Can take the state of.
[0121]
　The second switch 63 is, for example, a transistor. The second switch 63 is provided in series with the first switch 62 on the first line 6L1. The second switch 63 is provided on the first line 6L1 on the downstream side in the direction in which the current flows, with respect to the first switch 62. The second switch 63 is in either an ON state (state shown in FIGS. 16C and 16D) or an OFF state (state shown in FIGS. 16A and 16B) under the control of the control unit 44b (see FIG. 1). Can be taken.
[0122]
　The third switch 64 is, for example, a transistor. The third switch 64 is provided on the second line 6L2. The second line 6L2 is in parallel with the first line 6L1. The third switch 64 is in either an ON state (state shown in FIG. 16C) or an OFF state (state shown in FIGS. 16A, 16B, and 16D) under the control of the control unit 44b (see FIG. 1). Can take the state of.
[0123]
　The fourth switch 65 is, for example, a transistor. The fourth switch 65 is provided in series with the third switch 64 on the second line 6L2. The fourth switch 65 is provided on the second line 6L2 on the downstream side in the direction in which the current flows, with respect to the third switch 64. The fourth switch 65 is in either an ON state (state shown in FIGS. 16B and 16D) or an OFF state (state shown in FIGS. 16A and 16C) under the control of the control unit 44b (see FIG. 1). Can be taken.
[0124]
　The configuration of the electric motor 41 is as described above. The electric motor 41 is provided on the third line 6L3. The third line 6L3 connects the portion between the first switch 62 and the second switch 63 in the first line 6L1 and the portion between the third switch 64 and the fourth switch 65 in the second line 6L2. is doing.
[0125]
　The electric circuit 6 described above may have a non-energized state shown in FIG. 16A, a first driving state shown in FIG. 16B, a second driving state shown in FIG. 16C, and a braking state shown in FIG. 16D.
[0126]
　
　As shown in FIG. 16A, the non-energized state of the electric circuit 6 is a state in which the connection between the electric motor 41 and the power supply device 61 is disconnected (power supply from the power supply device 61 to the electric motor 41 is stopped. It is also called the state.). In the non-energized state of the electric circuit 6, the switches 62, 63, 64, and 65 are in the OFF state.
[0127]
　
　As shown in FIG. 16B, the first drive state of the electric circuit 6 is a state in which the electric motor 41 and the power supply device 61 are connected (power supply from the power supply device 61 to the electric motor 41 is permitted. It is also called the state.). In the first drive state of the electric circuit 6, the current flows through the circuit shown by the thick line in FIG. 16B.
[0128]
　In the first drive state of the electric circuit 6, a current in the first direction flows through the electric motor 41. The first direction is the direction from the first line 6L1 to the second line 6L2. In the first drive state of the electric circuit 6, the electric motor 41 rotates in the first direction (direction of arrow F2 in FIGS. 18A to 18C). In the first drive state of the electric circuit 6, the first switch 62 and the fourth switch 65 are in the ON state. Further, in the first drive state of the electric circuit 6, the second switch 63 and the third switch 64 are in the OFF state. The first drive state corresponds to an example of the drive state of the electric circuit.
[0129]
　
　As shown in FIG. 16C, the second drive state of the electric circuit 6 is a state in which the electric motor 41 and the power supply device 61 are connected (power supply from the power supply device 61 to the electric motor 41 is permitted. It is also called the state.). In the second drive state of the electric circuit 6, the current flows through the circuit shown by the thick line in FIG. 16C.
[0130]
　In the second drive state of the electric circuit 6, a current in the second direction flows through the electric motor 41. The second direction is the direction from the second line 6L2 to the first line 6L1. In the second drive state of the electric circuit 6, the electric motor 41 rotates (reverses) in the second direction (direction of arrow F1 in FIGS. 19A to 19C) . In the second drive state of the electric circuit 6, the second switch 63 and the third switch 64 are in the ON state. Further, in the second drive state of the electric circuit 6, the first switch 62 and the fourth switch 65 are in the OFF state. The second drive state corresponds to an example of the drive state of the electric circuit.
[0131]
　
　In the braking state of the electric circuit 6, as shown in FIG. 16D, the connection between the electric motor 41 and the power supply device 61 is disconnected (power supply from the power supply device 61 to the electric motor 41 is stopped), and A closed circuit 66 (a portion shown by a thick line in FIG. 16D) is formed in the electric circuit 6. That is, the electric circuit 6 has a closed circuit 66 in the braking state. The closed circuit 66 is a closed circuit including an electric motor 41, a second switch 63, and a fourth switch 65.
[0132]
　In the braking state of the electric circuit 6, the first switch 62 and the third switch 64 are in the OFF state. Further, in the braking state of the electric circuit 6, the second switch 63 and the fourth switch 65 are in the ON state. The operation of the electric circuit 6 will be described later.
[0133]
　
　An example of the operation of the cylinder connecting mechanism 45 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 cylinder connecting mechanism 45.
[0134]
　FIG. 18A 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. 18B is a schematic diagram 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. 18C 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.
[0135]
　The cylinder connecting mechanism 45 switches between an expanded state (see FIGS. 8, 12, and 18A) and a reduced state (see FIGS. 13 and 18C) based on the power (that is, rotational motion) of the electric motor 41. State transition. Hereinafter, with reference to FIGS. 18A to 18C, the operation of each part of the cylinder connecting mechanism 45 when the state transitions from the expanded state to the contracted state will be described.
[0136]
　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 the first missing tooth gear 450. Further, in FIGS. 18A to 18C, the lock mechanism 47 described later is omitted. The position of the first missing tooth gear 450 shown in FIG. 18A is defined as the reference position of the first missing tooth gear 450.
[0137]
　When the cylinder connecting mechanism 45 transitions from the expanded state to the contracted state, the control unit 44b switches the electric circuit 6 to the first drive state (see FIG. 16B). 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.
[0138]
　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.
[0139]
　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.
[0140]
　Specifically, first, in the first path and the second path, the first missing tooth gear 450 rotates in the front side in the rotation direction (direction indicated by arrow F2 in FIG. 18A) based on the power of the electric motor 41 . ..
[0141]
　In the first path and the second path, when the first missing tooth gear 450 rotates to the front side in the rotation direction, the first rack bar 451 moves to the + side in the Y direction (right side in FIGS. 18A to 18C) according to the rotation. Moving.
[0142]
　Then, when the first rack bar 451 moves in the Y direction + side in the first path, one cylinder connecting pin 454a is on the Y direction − side (left side of FIGS. 18A to 18C) via the first gear mechanism 452. Move to.
[0143]
　On the other hand, when the first rack bar 451 moves to the + side in the Y direction in the second path, the other cylinder connecting pin 454b moves to the + side in the Y direction 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 move in a direction approaching each other.
[0144]
　In the position information detection device 44, the pair of cylinder connecting pins 454a and 454b are detached from the pair of cylinder pin receiving portions 141a of the tip boom element 141 and are at predetermined positions (for example, the positions shown in FIGS. 2E and 18C). Detects that it has moved to. Then, based on the detection result, the control unit 44b stops the operation of the electric motor 41.
[0145]
　The state transition from the reduced state to the expanded state of the cylinder connecting mechanism 45 (that is, the state transition from FIG. 18C to FIG. 18A) is first when the brake mechanism 42 is released in the non-energized state of the electric motor 41. It is automatically performed based on the urging force of the urging mechanism 455. At this time, one cylinder connecting pin 454a and the other cylinder connecting pin 454b move in a direction away from each other.

WE CLAIMS

[Claim 1]From the actuator that expands and contracts the telescopic boom,
　the electric drive source that is provided in the actuator and is driven based on the power supply from the power source,
　the operating unit that operates based on the power of the electric drive source, and the power source
　. The driving state in which power supply to the electric drive source is permitted to drive the electric drive source and the braking force applied to the electric drive source by stopping the power supply from the power source to the electric drive source are applied. A 　working machine comprising an electric circuit capable of switching between a generated braking state and
　a control unit for controlling switching between the driving state and the braking state .
[Claim 2]
　The boom has a first boom element and a second boom element that extendably overlap each other, and the
　operating portion
　operates based on the power of the electric drive source, and the first boom element and the actuator are connected to each other. A first connecting mechanism that switches between a state and a non-connected state, and a
　second that operates based on the power of the electric drive source and switches between a connected state and a non-connected state of the first boom element and the second boom element. (Ii) The working machine according to claim 1, further comprising a connecting mechanism.
[Claim 3]
　The first connecting mechanism has a
　first urging mechanism,
　and based on the power of the electric drive source, the first boom element and the actuator are switched from a connected state to a non-connected state, and
　the first The working machine according to claim 2, wherein the first boom element and the actuator are switched from a non-connected state to a connected state based on the urging force of the urging mechanism.
[Claim 4]
　The second connecting mechanism has a
　second urging mechanism,
　and is switched from a connected state to a non-connected state between the first boom element and the second boom element based on the power of the electric drive source.
　The working machine according to claim 2 or 3, wherein the first boom element and the second boom element are switched from a non-connected state to a connected state based on the urging force of the second urging mechanism.
[Claim 5]
　The control unit is the electric circuit when the first connecting mechanism switches the first boom element and the actuator from the unconnected state to the connected state based on the urging force of the first urging mechanism. The working machine according to claim 3, wherein the braking state is set to.
[Claim 6]
　In the control unit, when the second connecting mechanism switches between the first boom element and the second boom element from the unconnected state to the connected state based on the urging force of the second urging mechanism. The working machine according to claim 4, wherein the electric circuit is in the braking state.
[Claim 7]
　The drive state includes a first drive state in which the electric drive source is rotated in the first direction and a second drive state in which the electric drive source is rotated in the second direction, and in
　the first drive state. 2. The first coupling mechanism operates based on the output of the electrical drive source, and in
　the second drive state, the second coupling mechanism operates based on the output of the electrical drive source. The working machine according to any one of 6.
[Claim 8]
　The electric circuit has a closed circuit including the electric drive source in the braking state, and the
　braking force is such that power generated based on the rotation of the electric drive source is consumed in the closed circuit. The working machine according to any one of claims 1 to 7, which is generated by the above.