Description:TECHNICAL FIELD
[0001] The present application relates to a drafting apparatus that drafts a fiber bundle.

BACKGROUND ART
[0002] PTL 1 is Japanese Patent Application Publication No. 2020-66820.
[0003] PTL 1 discloses a drafting apparatus of this type.
[0004] The drafting apparatus of PTL 1 is arranged at an air spinning apparatus. This drafting apparatus includes an endless apron belt. A sliver is stretched with the apron belt being driven cyclically while in contact with the sliver. The drafting apparatus of PTL 1 includes a traverse apparatus for traversing the apron belt. The traverse apparatus includes a guide and a drive. The guide guides the apron belt. The drive reciprocates the guide along the width direction of the apron belt.
[0005] By the traverse apparatus, the apron belt is reciprocated in the width direction with respect to a traveling path of the sliver. Accordingly, the progression of the wear at a specific portion of the apron belt can be prevented and the life of the apron belt can be extended.

SUMMARY OF THE INVENTION
[0006] Since an apron belt wears as it is used, it is necessary to replace it at a certain frequency. However, in the configuration of the above-mentioned PTL 1, it is difficult to detach the apron belt from the guide.
[0007] The present invention is made in view of the situation described above and its purpose is to provide a drafting apparatus that is easy to maintain, wherein an apron belt can be detached easily.

MEANS FOR SOLVING THE PROBLEMS AND EFFECTS THEREOF
[0008] The problem to be solved by the present invention is as described above. The means to solve this problem and the effects thereof will be described below.
[0009] An aspect of the present invention provides a drafting apparatus with a configuration as described below. That is, the drafting apparatus drafts a fiber bundle. The drafting apparatus includes an apron belt, a guide, and a drive. The apron belt runs cyclically while keeping contact with the fiber bundle. The guide guides the apron belt so that the apron belt traverses. The drive drives the guide in a first direction. The guide includes a protruding portion and a regulatory portion. The protruding portion protrudes in a second direction that is a different direction from the first direction and moves the apron belt along the first direction. The regulatory portion moves the apron belt along the first direction in a direction opposite to a direction in which the protruding portion moves the apron belt. The regulatory portion can perform movement relative to the protruding portion between a first position and a second position. When the regulation portion is at the first position, the apron belt is prevented from coming off from a space between the regulatory portion and the protruding portion in the first direction. When the regulation portion is at the second position, the apron belt is allowed to come off from the space between the regulatory portion and the protruding portion in the first direction. When the regulatory portion is at the first position, the regulatory portion is located at an opposite side with respect to the protruding portion in the first direction with the apron belt located between the regulatory portion and the protruding portion.
[0010] Accordingly, the apron belt can be traversed by the protruding portion and the regulatory portion which is positioned at the first position, and thus the apron belt can be prevented from wearing at a specific portion. During maintenance, the apron belt can be easily attached and detached with respect to the guide by making the regulatory portion to perform the relative movement with respect to the protruding portion and moving it to the second position.
[0011] In the above-described drafting apparatus, it is preferable that the regulatory portion can perform relative movement between the first position and the second position while remaining attached to the guide.
[0012] Accordingly, the maintenance of the apron belt can be simpler since the regulatory portion does not need to be completely detached from the guide. In addition, the regulatory portion can be prevented from being lost or the like.
[0013] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, the regulatory portion is so arranged that it is rotatable about an axis in a third direction that is orthogonal to the first direction and the second direction. In a process of the relative movement of the regulatory portion between the first position and the second potion, the regulatory portion rotates.
[0014] Accordingly, the movement of the regulatory portion between the first position and the second position can be achieved with a simple operation.
[0015] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, the regulatory portion is attached in such a way that the regulatory portion is movable with respect to the guide in a direction parallel to the second direction. In a process of the relative movement of the regulatory portion between the first position and the second position, the regulatory portion moves parallel to the second direction.
[0016] Accordingly, the relative movement of the regulatory portion between the first position and the second position can be achieved with a simple operation.
[0017] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, a first guiding recess and a second guiding recess are formed at one of the regulatory portion and the guide. The first guiding recess includes a portion that is parallel to the second direction. The second guiding recess includes a first guiding portion that is parallel to the second direction and a second guiding portion that is substantially arc-shaped. Another of the regulatory portion and the guide includes a first protrusion and a second protrusion. The first protrusion can perform relative movement along the first guiding recess. The second protrusion can perform relative movement along the second guiding recess. In a process of the relative movement of the regulatory portion between the first position and the second position, movement along a longitudinal direction of the first guiding portion and rotation about a center of an arc of the second guiding portion are performed.
[0018] Accordingly, with the combination of the parallel movement and the rotation, a space required for the relative movement of the regulatory portion between the first position and the second position can be reduced.
[0019] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, the regulatory portion is comprised of an elastically deformable member that is separate from the guide. The regulatory portion includes a first contacting portion and a second contacting portion and a connecting portion. The first contacting portion contacts with the guide from one side in a third direction that is orthogonal to the first direction and the second direction. The second contacting portion contacts with the guide from a side opposite to the one side from which the first contacting portion contacts in the third direction. The connecting portion connects the first contacting portion and the second contacting portion. The regulatory portion sandwiches the guide between the first contacting portion and the second contacting portion while being elastically deformed.
[0020] Accordingly, the regulatory portion can be attached to the guide with a simple configuration using the restoring force generated when the regulatory portion is elastically deformed.
[0021] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, a retaining protrusion is arranged at at least one of the guide or the regulatory portion and a retaining recess is arranged at another of the guide and the regulatory portion. When the regulatory portion is at the first position, the retaining protrusion is inserted into the retaining recess.
[0022] With this configuration, when the regulatory portion is at the first position, the elastic force of the regulatory portion always acts in such a direction that it prevents the retaining protrusion from coming off the retaining recess. Accordingly, the regulatory portion can be prevented from performing unintended movement from the first position to the second position. In addition, when the regulatory portion is to be moved relatively from the second position to first position, an operator can clearly determine that the movement is complete from a feeling received by their hand as the retaining protrusion is inserted into the retaining recess.
[0023] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, at least one of the first contacting portion or the second contacting portion includes a curved face at an end portion facing the apron belt. When the regulatory portion is at the first position, the curved face prevents the apron belt from coming off from a space between the regulatory portion and the protruding portion in the first direction.
[0024] Accordingly, the curved face, which is formed not to be sharp, contacts with the apron belt and traverses the apron belt. Therefore, the apron belt can be prevented from being damaged.
[0025] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, at least one of the first contacting portion or the second contacting portion includes a tapered portion that increases its distance from the guide as it approaches an end portion facing the apron belt in the first direction. When the regulatory portion at the first position is in contact with the apron belt, the tapered portion is spaced apart from the apron belt.
[0026] Accordingly, the regulatory portion can be easily attached to the guide during manufacture of the drafting apparatus by utilizing the tapered portion. Since the tapered portion does not contact with the apron belt during the traverse, the apron belt can be prevented from being damaged.
[0027] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, a first guiding recess and a second guiding recess are formed at one of the regulatory portion and the guide. The first guiding recess includes a portion that is parallel to the second direction. The second guide recess includes a portion that is parallel to the second direction. Another of the regulatory portion and the guide includes a first protrusion and a second protrusion. The first protrusion can perform relative movement along the first guiding recess. The second protrusion can perform relative movement along the second guiding recess. When the regulatory portion at the first position is viewed along the second direction, a bent portion that is convex to the guide is formed at at least one of the first contacting portion or the second contacting portion. When the regulatory portion at the first position is viewed along the second direction, a position at which the bent portion contacts with the guide is located between a center of the first protrusion and a center of the second protrusion in the first direction.
[0028] Accordingly, the regulatory portion can be stably attached since the force exerted by the regulatory portion against the guide in order to sandwich it is unlikely to be transmitted unevenly.
[0029] In the above-described drafting apparatus, it is preferable to include a configuration as follows. That is, when viewed along the first direction, a relative protrusion distance, which is a relative distance for which the first contacting portion or the second contacting portion protrudes in the second direction from its intersection with a traveling path of the apron belt, is different between the first contacting portion and the second contacting portion. When the regulatory portion is at the first position, one of the first contacting portion and the second contacting portion whose relative protrusion distance is larger prevents the apron belt from coming off from a space between the regulatory portion and the protruding portion in the first direction.
[0030] Accordingly, stable traverse of the apron belt can be achieved since the contacting portion that can effectively regulate for a longer length moves the apron belt.

BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a front view of a spinning machine according to one embodiment of the present invention.
FIG. 2 is a side view of a spinning unit.
FIG. 3 is a schematic side view of a drafting apparatus.
FIG. 4 is a perspective view of a drafting apparatus.
FIG. 5 is a perspective view showing a configuration of a guide in detail, as viewed from a rear side.
FIG. 6 is a perspective view illustrating a situation in which a spring clip has moved to a retracted position, as viewed from a rear side.
FIG. 7 is an enlarged plan view of a guide.
FIG. 8 is a perspective view illustrating an operation of attaching a spring clip to a guide.
FIG. 9 is a perspective view illustrating a positional relation between a spring clip and a bottom apron belt.
FIG. 10 is a schematic drawing showing a variation of a guide.

EMBODIMENT FOR CARRYING OUT THE INVENTION
[0032] Next, a spinning machine 1 that includes a drafting apparatus 5 according to one embodiment of the present invention will be described below with reference to the drawings. The spinning machine 1 shown in FIG. 1 includes more than one spinning unit 2 arranged side by side, a frame 3, and a yarn joining cart 30.
[0033] As shown in FIG. 2, each of the spinning units 2 includes, in order form upstream to downstream, a fiber bundle guide 4, the drafting apparatus 5, an air spinning apparatus 6, a yarn monitoring apparatus 7, a yarn storage apparatus (a drawing apparatus) 8, and a winding apparatus 9. Each apparatus that the spinning unit 2 includes is supported by the frame 3. In the present specification, the terms “upstream” and “downstream” shall mean the upstream and the downstream in a traveling direction of the fiber bundle and the yarn during spinning.
[0034] The fiber bundle guide 4 guides a fiber bundle 10 supplied from a sliver case that is not shown in the drawings. The fiber bundle 10 guided by the fiber bundle guide 4 is fed to the drafting apparatus 5.
[0035] The drafting apparatus 5 drafts the fiber bundle 10. The drafting apparatus 5 includes a draft bottom roller group 5a and a draft top roller group 5b as components for drafting. The draft bottom roller group 5a includes more than one draft bottom roller. The draft bottom rollers are rotationally driven by motors not shown in the drawings. The draft top roller group 5b includes more than one draft top roller. The draft bottom rollers and the draft top rollers are arranged to face each other. By conveying the fiber bundle 10 while sandwiching it between the draft bottom rollers and the draft top rollers, the fiber bundle 10 can be stretched. The drafting apparatus 5 will be described in detail later.
[0036] The air spinning apparatus 6 can perform air spinning by generating a swirling airflow inside. The air spinning apparatus 6 performs spinning by applying twists to the fiber bundle 10 supplied from the drafting apparatus 5 with the swirling airflow to form a yarn 15. Instead of the air spinning apparatus 6, an apparatus that performs a ring spinning may be used.
[0037] The yarn 15 formed by the air spinning apparatus 6 passes through the yarn monitoring apparatus 7. The yarn monitoring apparatus 7 monitors the thickness of the traveling yarn 15 using an optical sensor not shown in the drawings. When the yarn monitoring apparatus 7 detects a yarn defect in the yarn 15 (for example, a point where the thickness of the yarn 15 is abnormal), it sends a yarn defect detection signal to a unit controller 26. When the unit controller 26 receives the yarn defect detection signal, it cuts the yarn 15. The unit controller 26 may stop the air spinning apparatus 6 to cut the yarn 15, or may drive a cutter to cut the yarn 15. Instead of the optical sensor, the yarn monitoring apparatus 7 may use, for example, a capacitive sensor to monitor the thickness of the yarn 15. As yarn defects, a foreign substance included in the yarn 15 and/or an abnormal tension of the yarn 15 may be monitored.
[0038] After traveling through the yarn monitoring apparatus 7, the yarn 15 is wound on a bobbin 17 by the winding apparatus 9. The winding apparatus 9 winds the yarn 15 to produce a package 18. The winding apparatus 9 includes a cradle arm 19, a winding drum 20, and a traverse apparatus 21.
[0039] The cradle arm 19 rotatably supports the bobbin 17 for winding the yarn 15 thereon. Being rotationally driven while making contact with the outer peripheral surface of the bobbin 17 or the outer peripheral surface of the package 18, the winding drum 20 rotates the bobbin 17 (or the package 18). The traversing apparatus 21 includes a traverse guide 22. The traverse guide 22 is driven in a winding width direction of the bobbin 17 while being engaged with the yarn 15. Accordingly, the yarn 15 to be wound onto the bobbin 17 can be traversed.
[0040] With the spinning unit 2 with the configuration as described above, the yarn 15 can be formed from the fiber bundle 10 and be wound onto the bobbin 17.
[0041] In the spinning machine 1 of the present embodiment, the yarn storage apparatus 8 is arranged between the yarn monitoring apparatus 7 and the winding apparatus 9. As shown in FIG. 2, the yarn storage apparatus 8 includes a yarn storage roller 23 and an electric motor 25 that rotationally drives the yarn storage roller 23.
[0042] With the electric motor 25 rotationally driving the yarn storage roller 23, the yarn storage apparatus 8 draws out the yarn 15 from the air spinning apparatus 6. The yarn storage roller 23 can wind and temporarily store the drawn yarn 15 by winding the yarn 15 on its outer peripheral surface. Since the yarn 15 is temporarily stored in this manner, the yarn storage apparatus 8 functions as a kind of a buffer. This can eliminate problems (for example, slack of the yarn 15) that occur when the speed of spinning by the air spinning apparatus 6 and the speed of winding by the winding apparatus 9 do not match for some reason.
[0043] Each of the spinning units 2 includes the unit controller 26. The unit controller 26 controls each configuration that the spinning unit 2 includes. One unit controller 26 may be configured to control two or more predetermined number of the spinning units 2.
[0044] As shown in FIG. 1 and FIG. 2, the yarn joining cart 30 includes a yarn joining apparatus 31, a suction pipe 32, and a suction mouth 33.
[0045] The yarn joining apparatus 31 is an apparatus for joining ends of yarns together. The configuration of the yarn joining apparatus 31 is not particularly limited. For example, a pneumatic splicer that twists ends of yarns together by a swirling airflow may be employed. The yarn joining apparatus 31 may be a knotter that mechanically ties ends of yarns together. The suction pipe 32 sucks and captures an end of the yarn delivered from the air spinning apparatus 6 and guides it to the yarn joining apparatus 31. The suction mouth 33 sucks and captures an end of the yarn from the package 18 supported by the winding apparatus 9 and guides it to the yarn joining apparatus 31.
[0046] The yarn joining apparatus 31 joins ends of yarns guided by the suction pipe 32 and the suction mouth 33. Accordingly, the cut yarn 15 becomes continuous again between the air spinning apparatus 6 and the winding apparatus 9.
[0047] Next, with reference to FIG. 3, the drafting apparatus 5 will be described.
[0048] As shown in FIG. 3, the drafting apparatus 5 includes a base member 50. The base member 50 is, for example, a frame-like or block-like member. The base member 50 is fixed to the frame 3 by suitable means.
[0049] The draft bottom roller group 5a and the air spinning apparatus 6 are attached to the base member 50. The base member 50 supports the draft bottom roller group 5a and the air spinning apparatus 6. As shown in FIG. 3, the draft bottom roller group 5a includes a front bottom roller (a first roller) 51, a middle bottom roller (a second roller) 52, a third bottom roller (a third roller) 53, and a back bottom roller (a fourth roller) 54 that are arranged in the order from downstream to upstream in the fiber traveling direction. A tensor bar (a belt guiding member) 56 is arranged downstream of the middle bottom roller 52 in the fiber traveling direction. A bottom apron belt (an apron belt) 57 is looped around the middle bottom roller 52 and the tensor bar 56. Since the fiber bundle 10 is drafted in the fiber traveling direction in the drafting apparatus 5, a direction of drafting is parallel to the fiber traveling direction.
[0050] The central axes of the draft rollers that comprise the draft bottom roller group 5a are all parallel to each other. In the following description, a direction parallel to the axial directions of the draft rollers in the draft bottom roller group 5a may be referred to a roller axial direction.
[0051] The drafting apparatus 5 includes more than one motor not shown in the drawings. Each of the motors can rotationally drive the front bottom roller 51, the middle bottom roller 52, the third bottom roller 53, and the back bottom roller 54.
[0052] As shown in FIG. 3, the drafting apparatus 5 includes a draft cradle 70. The draft top roller group 5b is attached to the draft cradle 70 and the draft cradle 70 supports the draft top roller group 5b. The draft cradle 70 can be opened and closed with respect to the base member 50. When the draft cradle 70 is closed, the draft top roller group 5b comes into contact with or comes close to the daft bottom roller group 5a. As shown in FIG. 3, the draft top roller group 5b includes a front top roller 71, a middle top roller 72, a third top roller 73, and a back top roller 74 arranged in the order from downstream to upstream in the fiber traveling direction. A top apron belt (a nip apron belt) 77 is looped around the middle top roller 72.
[0053] As shown in FIG. 4, the drafting apparatus 5 includes a first support 61, a second support 62, a third support 63, and a fourth support 64. Each of the first support 61, the second support 62, the third support 63, and the fourth support 64 is formed integrally with the base member 50 or is attached directly or indirectly to the base member 50.
[0054] The first support 61 and the second support 62 are located only at one side in the roller axial direction with respect to the traveling path of the fiber bundle 10 in the drafting apparatus 5. The first support 61 supports the front bottom roller 51 in a cantilever manner. The second support 62 supports the middle bottom roller 52 in a cantilever manner.
[0055] The third support 63 supports both ends of the third bottom roller 53. The fourth support 64 supports both ends of the back bottom roller 54.
[0056] A supporting arm 58 is fixed to the second support 62. The supporting arm 58 extends in the roller axial direction to protrude from the second support 62 and the tensor bar 56 is fixed to its end portion. The tensor bar 56 is arranged between the front bottom roller 51 and the middle bottom roller 52. The second support 62 supports the tensor bar 56 in a cantilever manner with the supporting arm 58.
[0057] An end of each of the middle bottom roller 52 and the tensor bar 56 further from the second support 62 is a free end. Therefore, the bottom apron belt 57 can be detached from the middle bottom roller 52 and the tensor bar 56 by drawing out the bottom apron belt 57 in a direction away from the second support 62 in the axial direction of the middle bottom roller 52. In the following description, in the roller axial direction, a side closer to the free end of the middle bottom roller 52 may be referred to as a free end side S1 and a side opposite to the free end may be referred to as a support side S2.
[0058] Next, an apron traverse apparatus 84 that the drafting apparatus 5 includes will be described.
[0059] The apron traverse apparatus 84 can traverse the bottom apron belt 57 within a predetermined stroke. The apron traverse apparatus 84 is arranged at the base member 50. The apron traverse apparatus 84 includes an arm member (a guide) 85 and a motor (a drive) 86.
[0060] The arm member 85 is an elongate plate-shaped member that extends in the roller axial direction. The arm member 85 is made of suitable materials such as metal. A long and narrow space that extends in the roller axial direction is formed between the first support 61 and the second support 62. The arm member 85 is inserted into this space with its thickness direction oriented in the fiber traveling direction. The arm member 85 is supported by the second support 62 in such a way that the arm member 85 can slide in the roller axial direction.
[0061] Two fulcrum members 87 are arranged side by side at the second support 62. The two fulcrum members 87 constitute a slide guide that guides the bottom apron belt 57 in the traversing direction. In the following description, the traversing direction of the bottom apron belt 57 may be referred to as an apron traverse direction (a first direction) D1. The apron traverse direction D1 substantially coincides with the roller axial direction. The direction in which the two fulcrum members 87 are aligned coincides with the roller axial direction. Two elongate holes 88 are formed through the arm member 85 for the two fulcrum members 87. Each of the elongate holes 88 extends in the roller axial direction. The fulcrum member 87 can guide the arm member 85 so that it moves along the roller axial direction.
[0062] The arm member 85 is so arranged that one of its longitudinal ends protrudes from a space between the first support 61 and the second support 62 in the roller axial direction. This protruding portion is located below the tensor bar 56. An action portion 89 is formed on this protruding portion of the arm member 85. The action portion 89 is a recess which opens upward. The width of the recess accommodates to the width of the bottom apron belt 57. The bottom apron belt 57 which is looped around the middle bottom roller 52 and the tensor bar 56 passes through the recess.
[0063] By reciprocating the arm member 85 in the roller axial direction, the bottom apron belt 57 can be reciprocated in the roller axial direction with the action portion 89. Accordingly, the bottom apron belt 57 can be moved periodically with respect to the fiber bundle path. As a result, the bottom apron belt 57 is less prone to wear at a specific portion, and thus the frequency of the maintenance such as replacing the bottom apron belt 57.
[0064] The motor 86 is arranged on the side opposite to the fiber bundle traveling path with the second support 62 between them. The motor 86 may be configured as, for example, a stepping motor, but is not limited to it.
[0065] The output shaft of the motor 86 is arranged substantially parallel to the fiber traveling direction. An eccentric cam (a rotating cam) 90 is fixed to the output shaft of the motor 86. A cam hole 92 is formed through the arm member 85. The cam hole 92 extends in the vertical direction and the eccentric cam 90 can be inserted into it. When the motor 86 is driven, the eccentric cam 90 is rotated. This rotational motion is converted via the cam hole 92 into a reciprocal motion of the arm member 85 in the roller axial direction. By driving the motor 86 in this configuration, the bottom apron belt 57 can be traversed in the apron traverse direction D1 with the arm member 85.
[0066] Next, the configuration of the action portion 89 will be described in detail.
[0067] The arm member 85 includes a protruding portion 35 and a spring clip (a regulatory portion) 40. The protruding portion 35 and the spring clip 40 are arranged side by side along the roller axial direction. The spring clip 40 is arranged on the free end side S1 compared to the protruding portion 35. The protruding portion 35 and the spring clip 40 are arranged in such a way that they sandwich the traveling path of the bottom apron belt 57. The protruding portion 35 and the spring clip 40 both protrude from the arm member 85 in an upward direction (a second direction) D2. The upward direction D2 can be described as a direction that intersects (preferably, at a right angle) the traveling path of the bottom apron belt 57 when viewed along the apron traverse direction D1. The relative recess formed between the protruding portion 35 and the spring clip 40 corresponds to the action portion 89.
[0068] Each of the protruding portion 35 and the spring clip 40 can contact with one of end portions in the widthwise direction of the bottom apron belt 57 that runs cyclically. Portions of both of the protruding portion 35 and the spring clip 40 that contact with the bottom apron belt 57 are preferably substantially perpendicular to the width direction of the apron belt 57.
[0069] The protruding portion 35 is integrally formed with the arm member 85, for example, as shown in FIG. 5.
[0070] The spring clip 40 is a component separate from the arm member 85. The spring clip 40 is comprised of an elastic, thin, plate-shaped metal member. The spring clip 40 is attached to the arm member 85 in such a way that it sandwiches the plate-shaped arm member 85 from both sides and is fixed utilizing its elasticity. The spring clip 40 can change its mounting position with respect to the arm member 85.
[0071] A first contacting portion 40a, a second contacting portion 40b, and a connecting portion 40c are formed integrally to comprise the spring clip 40. Both of the first contacting portion 40a and the second contacting portion 40b are plate-shaped portions that are approximately rectangular. The connecting portion 40c is formed as an arc-shaped face and it connects the first contacting portion 40a and the second contacting portion 40b. The first contacting portion 40a and the second contacting portion 40b are arranged to face each other. The distance between the first contacting portion 40a and the second contacting portion 40b can be widened mainly with the elastic deformation of the connecting portion 40c.
[0072] With the spring clip 40 attached to the arm member 85, the first contacting portion 40a and the second contacting portion 40b are located at opposite sides across the arm member 85 with respect to each other. The first contacting portion 40a contacts with a face of the plate-shaped arm member 85 at one side in its thickness direction. The second contacting portion 40b contacts with a face of the arm member 85 at the other side in its thickness direction. The connecting portion 40c is positioned to circumvent the longitudinal end of the arm member 85.
[0073] As described above, the spring clip 40 is arranged on the lateral side of the traveling path of the bottom apron belt 57. The connecting portion 40c is arranged at a side further from the traveling path of the bottom apron belt 57. The first contacting portion 40a includes a larger dimension in the width direction of the bottom apron belt 57 compared to the second contacting portion 40b. Accordingly, since the first contacting portion 40a is closer to the traveling path of the bottom apron belt 57 than the second contacting portion 40b, only the first contacting portion 40a can contact with the bottom apron belt 57.
[0074] At an edge of the rectangular shaped first contacting portion 40a which faces the bottom apron belt 57, a curved face 43 is formed as shown in FIG. 5. The curved face 43 is constructed by rounding the edge of the first contacting portion 40a into a cylindrical shape with a small diameter. Accordingly, the thin edge of the plate-shaped spring clip 40 can be prevented from coming into contact with the bottom apron belt 57 and damaging it.
[0075] The arm member 85 includes a first guiding protrusion (a first protrusion) 36 and a second guiding protrusion (a second protrusion) 37. The first guiding protrusion 36 and the second guiding protrusion 37 are arranged at a portion of the arm member 85 to which the spring clip 40 is attached. Each of the first guiding protrusion 36 and the second guiding protrusion 37 protrudes in the thickness direction of the arm member 85 which is formed in a plate-shape. The first guiding protrusion 36 and the second guiding protrusion 37 are both formed in a short cylindrical shape.
[0076] A first guiding recess 41 and a second guiding recess 42 are formed at the first contacting portion 40a of the spring clip 40. Each of the first guiding recess 41 and the second guiding recess 42 is configured as a groove that goes through the first contacting portion 40a in the thickness direction. The first guiding protrusion 36 is inserted into the first guiding recess 41 and the second guiding protrusion 37 is inserted into the second guiding recess 42.
[0077] The first guiding recess 41 is formed in a liner shape that extends in the vertical direction. The second guiding recess 42 includes a first guiding portion 42a that is in a liner shape extending in the vertical direction and a second guiding portion 42b that is arc-shaped and elongate.
[0078] The longitudinal direction of the first guiding portion 42a is arranged substantially parallel to the longitudinal direction of the first guiding recess 41. The second guiding portion 42b is formed in an arc shape whose center is the top end of the first guiding recess 41.
[0079] When the spinning machine 1 is performing spinning, the spring clip 40 is at a regulatory position (a first position) P1 shown in FIG. 5. At this time, the first guiding protrusion 36 is positioned at the bottom end of the first guiding recess 41 and the second guiding protrusion 37 is positioned at the bottom end of the first guiding portion 42a of the second guiding recess 42. As the protruding portion 35 does, the spring clip 40 at the regulatory position P1 moves integrally with the arm member 85 which moves back and forth in the apron traverse direction D1. Accordingly, the traversing of the bottom apron belt 57 is achieved.
[0080] In the apron traverse direction D1, the dimension of the first guiding recess 41 is substantially equal to the dimension of the first guiding protrusion 36 and the dimension of the first guiding portion 42a is substantially equal to the dimension of the second guiding protrusion 37. Therefore, when the spring clip 40 pushes the bottom apron belt 57 toward the support side S2, the reaction force will not cause any unintended relative movement of the spring clip 40 toward the free end side S1.
[0081] At the first contacting portion 40a, a small retaining protrusion 44 that protrudes toward the second contacting portion 40b is formed. At the arm member 85, a retaining recess 38 is formed. The location of the retaining protrusion 44 when the spring clip 40 is at the regulatory position P1 corresponds to the location of the retaining recess 38. When the spring clip 40 is at the regulatory position P1, an elastic force generated at the spring clip 40 makes the retaining protrusion 44 enter the retaining recess 38. Accordingly, unintended movement of the spring clip 40 from the regulatory position P1 can be prevented.
[0082] When the replacement of the bottom apron belt 57 is needed, an operator firstly stops the spinning machine 1 and opens the draft cradle 70 of the drafting apparatus 5. The operator then grasps a top portion of the spring clip 40 with their fingers and pulls it down as shown by an arrow O1 in FIG. 5. Accordingly, the spring clip 40 can be moved downward in a parallel way with respect to the arm member 85. At this time, the first guiding recess 41 and the first guiding portion 42a of the second guiding recess 42 guide the direction of movement of the spring clip 40.
[0083] After the spring clip 40 is pulled down, the first guiding protrusion 36 is positioned at the top end of the first guiding recess 41 and the second guiding protrusion 37 is positioned at the top end of the first guiding portion 42a of the second guiding recess 42 (in other words, at a portion where the first guiding portion 42a and the second guiding portion 42b connect with each other).
[0084] The operator then pulls the spring clip 40 toward the free end side S1 as shown by an arrow O2 keeping grasping the top portion with their fingers. As a result, the spring clip 40 rotates around the first guiding protrusion 36 positioned at the top end of the first guiding recess 41 as the center and the spring clip 40 retracts in such a way that its top portion gets separated from the traveling path of the bottom apron belt 57. At this time, the second guiding portion 42b of the second guiding recess 42 guides the rotation of the spring clip 40. In the following description, the axial direction of the first guiding protrusion 36 may be referred to as a rotational axis direction (a third direction) D3. The rotational axis direction D3 is perpendicular to the above-mentioned apron traverse direction D1 as well as to the upward direction D2. The rotational axis direction D3 substantially coincides with the thickness direction of the arm member 85 which is formed in a plate-shape.
[0085] The rotation of the spring clip 40 about the lower portion (the first guiding protrusion 36) further reduces the substantial length of upward protrusion of the spring clip 40. In the above manner, the movement to the retracted position (a second position) P2 as shown in FIG. 6 is achieved. The movement of the spring clip 40 with respect to the arm member 85 can be reworded as the relative movement of the spring clip 40 with respect to the protruding portion 35.
[0086] In the present embodiment, more than one drafting apparatus 5 is arranged side by side with a predetermined pitch. In addition, it is expected that a lot of components will be arranged around the bottom apron belt 57. Therefore, it is highly likely that a space around the spring clip 40 will not be so large. In this regard, in the present embodiment, the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 is achieved by the combination of the parallel movement and the rotation. Accordingly, switching between the regulatory position P1 for traversing the bottom apron belt 57 and the retracted position P2 suitable for performing maintenance on the bottom apron belt 57 can be achieved while reducing the space required for the movement of the spring clip 40.
[0087] In the arm member 85, an inclined protrusion 39 is formed integrally with the top edge of the portion to which the spring clip 40 is attached. When the spring clip 40 is moved to the retracted position P2, as shown in FIG. 6, the inclined protrusion 39 is substantially exposed. The inclined protrusion 39 includes an inclined portion that the amount of protrusion in the upward direction D2 gradually increases as the distance from the traveling path of the bottom apron belt 57 increases.
[0088] When the spring clip 40 is moved to the retracted position P2, the curved face 43 of the spring clip 40 (in other words, the edge portion of the spring clip 40 that contacts with the bottom apron belt 40 to traverse the bottom apron belt 57) is placed lower than the contour of the top edge of the inclined protrusion 39. When the bottom apron belt 57 is drew out toward the free end side S1 as shown by the arrow O3 in FIG. 6, the bottom apron belt 57 is deformed to become concave upwardly by the action of the inclined protrusion 39 in the process of approaching the spring clip 40. Therefore, the bottom apron belt 57 can easily pass above the spring clip 40. As a result, the bottom apron belt 57 can be removed smoothly. In addition, the inclined protrusion 39 prevents the bottom apron belt 57 from coming into contact with the top edge of the spring clip 40 when the bottom apron belt 57 is detached and when a new bottom apron belt 57 is attached. Therefore, the bottom apron belt 57 can be prevented from being damaged.
[0089] After detaching the bottom apron belt 57 by drawing it out to the free end side S1, the operator attaches a new bottom apron belt 57 to the middle bottom roller 52 and the tensor bar 56 from the free end side S1. The operator then moves the spring clip 40 from the retracted position P2 to the regulatory position P1. This operation can be achieved by performing the above-described procedure in reverse order, so its description is omitted.
[0090] In the present embodiment, when the spring clip 40 is at the regulatory position P1 as shown in FIG. 5, the distance of protrusion of the spring clip 40 in the upward direction D2 is sufficient as well as the protrusion distance of the protruding portion 35. Therefore, unintended detachment of the bottom apron belt 57 toward the free end side S1 can be prevented. This means that the spring clip 40 can surely push the bottom apron belt 57 toward the support side S2 and traverse it. On the other hand, when the spring clip 40 is moved to the retracted position P2 as shown in FIG. 6, the top portion of the spring clip 40 is placed away from the bottom apron belt 57 toward the free end side S1 and the distance of protrusion of the spring clip 40 in the upward direction D2 becomes smaller. Therefore, the spring clip 40 is less prone to interfere with the bottom apron belt 57 when the bottom apron belt 57 is drew out to the free end side S1 and detached, and thus it is easy to perform the maintenance.
[0091] The movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 can be achieved simply by the operator grasping the spring clip 40 with their fingers and applying force. Therefore, since no tools are required, workability is high.
[0092] Instead of moving the spring clip 40 to the retracted position P2 shown in FIG. 6, the spring clip 40 can be physically detached from the arm member 85 to achieve the relative movement of the spring clip 40 with respect to the protruding portion 35. However, in this configuration, the operation of attaching/detaching the spring clip 40 can be complicated and the operator can lose the detached spring clip 40. In this regard, in the present embodiment, the movement of the spring clip 40 to the retracted position P2 is achieved while maintaining the spring clip 40 attached to the arm member 85. In other words, once the spring clip 40 is attached to the arm member 85, it is difficult to detach it without using a tool. Accordingly, the simplification of the maintenance operation and the prevention of the loss of the spring clip 40 can be achieved.
[0093] The spring clip 40 is comprised of elastic material and it is secured sandwiching the arm member 85 between the first contacting portion 40a and the second contacting portion 40b while being elastically deformed. Therefore, the elastic force that the spring clip 40 itself includes acts in such a way it prevents the first guiding protrusion 36 and the second guiding protrusion 37 from coming off the first guiding recess 41 and the second guiding recess 42. Accordingly, the spring clip 40 can be prevented from coming off the arm member 85 with a simple configuration.
[0094] The elastic force of the spring clip 40 is also utilized to prevent the retaining protrusion 44 from coming off the retaining recess 38 when the spring clip is at the regulatory position P1. When the spring clip 40 is moved from the retracted position P2 to the regulatory position P1, the retaining protrusion 44 is inserted into the retaining recess 38 in the end by the action of the elastic force. Therefore, the operator can determine that the movement of the spring clip 40 to the regulatory position P1 is complete from a tactile feeling received by their fingers.
[0095] Next, a bent portion 45 and a tapered portion 46 that the second contacting portion 40b includes.
[0096] FIG. 7 shows an enlarged plan view of the spring clip 40 positioned at the regulatory position P1. FIG. 7 can be considered as a drawing of the spring clip 40 viewed from a point of view parallel to the upward direction D2. As shown in FIG. 7, the connecting portion 40c is formed as an arc-shaped face whose angle is 180 degree and its diameter is larger than the thickness of the arm member 85. The second contacting portion 40b is arranged to be inclined in such a way that its distance from the first contacting portion 40a decreases as the distance from the portion that is connected to the connecting portion 40c increases.
[0097] As shown in FIG. 7, a V-shaped bent portion 45 is formed in the second contacting portion 40b. The second contacting portion 40b is bent to form a straight crease as the bent portion 45 as a border, as shown in FIG. 7.
[0098] In the second contacting portion 40b, the tapered portion 46 is formed at an opposite side with respect to the connecting portion 40c with the bent portion 45 between them. This tapered portion 46 is arranged to be inclined in such a way that its distance from the first contacting portion 40a increases as the distance from the end portion that faces the bottom apron belt 57 decreases. Specifically, in the tapered portion 46, the distance from the first contacting portion 40a gradually increases as the distance from the traveling path of the bottom apron belt 57 in the apron traverse direction D1 decreases.
[0099] Consider a cross-section of the spring clip 40 at the regulatory position P1 with a virtual plane parallel to both of the apron traverse direction D1 and the fiber traveling direction as a cutting plane. In this cross-section, if the tapered portion 46 increases its distance from the arm member 85 as the distance from the traveling path of the bottom apron belt 57 decreases, it can be said that "the tapered portion 46 increases its distance from the arm member 85 as it approaches the end portion facing the bottom apron belt 57 in the apron traverse direction D1. Therefore, when viewed along the fiber traveling direction, the orientation of the opening of the tapered portion 46 may not coincide with the apron traverse direction D1, but may be inclined. In addition, when viewed along the fiber traveling direction, the end portion of the tapered portion 46 that faces the bottom apron belt 57 may not be perpendicular to the apron traverse direction D1.
[0100] When the spring clip 40 is not elastically deformed, the distance between the bent portion 45 and the first contacting portion 40a is smaller than the thickness of the arm member 85. This distance may be zero. When the spring clip 40 is attached to the arm member 85, the distance between the bent portion 45 and the first contacting portion 40a is widened. This causes the spring clip 40 to be elastically deformed.
[0101] As described above, the second contacting portion 40b includes the tapered portion 46. With this configuration, when the spring clip 40 is attached to the arm member 85, as shown in FIG. 8, the distance between the second contacting portion 40b and the first contacting portion 40a is widen being guided by the tapered portion 46. Therefore, the workability of assembly is improved.
[0102] When the spring clip 40 is attached to the arm member 85, the bent portion 45 is convex to the arm member 85. Therefore, the second contacting portion 40b makes substantially linear contact with the arm member 85 only at the bent portion 45. On the other hand, the first contacting portion 40a does not include a portion that is convex to the arm member 85 except for the retaining protrusion 44. Therefore, since the retaining protrusion 44 is inserted into the retaining recess 38 when the spring clip 40 is at the regulatory position P1, the first contacting portion 40a makes surface contact with the arm member 85 with a large contacting area.
[0103] In the present embodiment, the first guiding recess 41, the second guiding recess 42, and the retaining protrusion 44 are arranged at the first contacting portion 40a which makes surface contact with the arm member 85. Correspondingly, the first guiding protrusion 36 and the second guiding protrusion 37 are arranged at a face of the arm member 85 at which it makes surface contact with the first contacting portion 40a. Accordingly, the spring clip 40 can be remained attached securely to the arm member 85 throughout the entire process of movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 without making the amount of protrusion of the first guiding protrusion 36 and the second guiding protrusion 37 large.
[0104] The above-mentioned first guiding protrusion 36 and the second guiding protrusion 37 are arranged in such a way that their positions are different in the apron traverse direction D1. As shown in FIG. 7, when the spring clip 40 is at the regulatory position P1, a position CP1 at which the bent portion 45 contacts with the arm member 85 is located between the center of the first guiding protrusion 36 and the center of the second guiding protrusion 37 in the apron traverse direction D1. Accordingly, the elastic force that the spring clip 40 includes can be prevented from being transmitted unevenly, and thus the first contacting portion 40a can be maintained in stable surface contact with the arm member 85. In other words, the first guiding protrusion 36 can be prevented from coming off the first guiding recess 41 and the second guiding protrusion 37 can be prevented from coming off the second guiding recess 42.
[0105] In the present embodiment, the first contacting portion 40a of the spring clip 40 is arranged at one side of the arm member 85 in its thickness direction and the second contacting portion 40b is arranged at the other side. Both of the first contacting portion 40a and the second contacting portion 40b face the traveling path of the bottom apron belt 57 in the apron traverse direction D1. When viewed along the apron traverse direction D1 as shown in FIG. 9, both of the end portion of the first contacting portion 40a and the end portion of the second contacting portion 40b intersect the traveling path of the bottom apron belt 57.
[0106] The traveling path of the bottom apron belt 57 is inclined with respect to the direction in which the first contacting portion 40a and the second contacting portion 40b faces each other (in other words, the thickness direction of the arm member 85.). Therefore, the relative protrusion distance L1 for which the first contacting portion 40a protrudes in the upward direction D2 from its intersection with the traveling path of the bottom apron belt 57 and the relative protrusion distance L2 for which the second contacting portion 40b protrudes in the upward direction D2 from its intersection with the traveling path of the bottom apron belt 57 are different from each other. The relative protrusion distance L1 of the first contacting portion 40a is larger than the relative protrusion distance L2 of the second contacting portion 40b.
[0107] In the present embodiment, as shown in FIG. 7, the curved face 43 for making contact with the bottom apron belt 57 and pushing it is formed at the first contacting portion 40a and the tapered portion 46 is formed at the second contacting portion 40b. It is possible to push the bottom belt 57 by the second contacting portion 40b, however, with this configuration, the bottom apron belt 57 can run up onto the spring clip 40 if the tension of the bottom apron belt 57 is not strong enough. In this regards, in the present configuration, since the first contacting portion 40a pushes the bottom apron belt 57, the end portion of the bottom apron belt 57 can be prevented from passing through the curved surface 43 and running up onto the spring clip 40. Since the first contacting portion 40a that can effectively regulate the bottom apron belt 57 for a longer length contacts with it and moves it, the stable traverse of the bottom apron belt 57 can be achieved.
[0108] FIG. 7 shows the curved face 43 contacting with the bottom apron belt 57 and moving it. Since the tapered portion 46 is positioned closer to the free end side S1 than the curved portion 43, the tapered portion 46 is spaced apart from the bottom apron belt 57. In this manner, since the tapered portion 46 does not contact with the bottom apron belt 57, the bottom apron belt 57 can be prevented from being damaged.
[0109] As described above, the drafting apparatus 5 of the present embodiment drafts the fiber bundle 10. The drafting apparatus 5 includes the bottom apron belt 57, the arm member 85, and the motor 86. The bottom apron belt 57 runs cyclically while keeping contact with the fiber bundle 10. The arm member 85 guides the bottom apron belt 57 so that the bottom apron belt 57 traverses. The motor 86 drives the arm member 85 in the apron traverse direction D1. The arm member 85 includes the protruding portion 35 and the spring clip 40. The protruding portion 35 protrudes in the upward direction D2 that is a different direction from the apron traverse direction D1 and moves the bottom apron belt 57 along the apron traverse direction D1. The spring clip 40 moves the bottom apron belt 57 along the apron traverse direction D1 in the direction opposite to the direction in which the protruding portion 35 moves the bottom apron belt 57. The spring clip 40 can perform the movement relative to the protruding portion 35 between the regulatory position P1 and the retracted position P2. When the spring clip 40 is at the regulatory position P1, the bottom apron belt 57 is prevented from coming off from the space between the spring clip 40 and the protruding portion 35 in the apron traverse direction D1. When the spring clip 40 is at the retracted position P2, the bottom apron belt 57 is allowed to come off from the space between the spring clip 40 and the protruding portion 35 in the apron traverse direction D1. When the spring clip 40 is at the regulatory position P1, the spring clip 40 is located at the opposite side with respect to the protruding portion 35 in the apron traverse direction D1 with the bottom apron belt 57 located between the spring clip 40 and the protruding portion 35.
[0110] Accordingly, the bottom apron belt 57 can be traversed by the protruding portion 35 and the spring clip 40 which is positioned at the regulatory position P1, and thus the bottom apron belt 57 can be prevented from wearing at a specific portion. During maintenance, the bottom apron belt 57 can be easily attached and detached with respect to the arm member 85 by making the spring clip 40 to perform the relative movement to the retracted position P2.
[0111] In the drafting apparatus 5 of the present embodiment, the spring clip 40 can perform the relative movement between the regulatory position P1 and the retracted position P2 while remaining attached to the arm member 85.
[0112] Accordingly, the maintenance on the bottom apron belt 57 can be simpler since the spring clip 40 does not need to be completely detached from the arm member 85. In addition, the spring clip 40 can be prevented from being lost or the like.
[0113] In the drafting apparatus 5 of the present embodiment, the spring clip 40 is so arranged that it is rotatable about the axis in the rotational axis direction D3. The rotational axis direction D3 is a direction orthogonal to the apron traverse direction D1 and the upward direction D2. In the process of the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2, the spring clip 40 rotates.
[0114] Accordingly, the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 can be achieved with a simple operation.
[0115] In the drafting apparatus 5 of the present embodiment, the spring clip 40 is attached in such a way that the spring clip 40 is movable with respect to the arm member 85 in a direction parallel to the upward direction D2. In the process of the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2, the spring clip 40 moves parallel to the upward direction D2.
[0116] Accordingly, the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 can be achieved with a simple operation.
[0117] In the drafting apparatus 5 of the present embodiment, the first guiding recess 41 and the second guiding recess 42 are formed at the spring clip 40. The first guiding recess 41 includes a portion that is parallel to the upward direction D2. The second guiding recess 42 includes the first guiding portion 42a that is parallel to the upward direction D2 and the second guiding portion 42b that is substantially arc-shaped. The arm member 85 includes the first guiding protrusion 36 and the second guiding protrusion 37. The first guiding protrusion 36 can perform relative movement along the first guiding recess 41. The second guiding protrusion 37 can perform relative movement along the second guiding recess 42. In the process of the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2, the movement along the longitudinal direction of the first guiding portion 42a and the rotation about the center of the arc of the second guiding portion 42b are performed.
[0118] Accordingly, with the combination of the parallel movement and the rotation, the space required for the relative movement of the spring clip 40 between the regulatory position P1 and the retracted position P2 can be reduced.
[0119] In the drafting apparatus 5 of the present embodiment, the spring clip 40 is comprised of an elastically deformable member that is separate from the arm member 85. The spring clip 40 includes the first contacting portion 40a, the second contacting portion 40b, and the connecting portion 40c. The first contacting portion 40a contacts with the arm member 85 from one side in the rotational axis direction D3. The rotational axis direction D3 is orthogonal to the apron traverse direction D1 and the upward direction D2. The second contacting portion 40b contacts with the arm member 85 from a side opposite to the one side from which the first contacting portion 40a contacts in the rotational axis direction D3. The connecting portion 40c connects the first contacting portion 40a and the second contacting portion 40b. The spring clip 40 sandwiches the arm member 85 between the first contacting portion 40a and the second contacting portion 40b while being elastically deformed.
[0120] Accordingly, the spring clip 40 can be attached to the arm member 85 with a simple configuration using the restoring force generated when the spring clip 40 is elastically deformed.
[0121] In the drafting apparatus 5 of the present embodiment, the retaining protrusion 44 is arranged at at least one of the arm member 85 or the spring clip 40 and the retaining recess 38 is arranged at another of the arm member 85 and the spring clip 40. When the spring clip 40 is at the regulatory position P1, the retaining protrusion 44 is inserted into the retaining recess 38.
[0122] With this configuration, when the spring clip 40 is at the regulatory position P1, the elastic force of the spring clip 40 always acts in such a direction that it prevents the retaining protrusion 44 from coming off the retaining recess 38. Accordingly, the spring clip 40 can be prevented from performing unintended movement from the regulatory position P1 to the retracted position P2. In addition, when the spring clip 40 is to be moved relatively from the retracted position P2 to the regulatory position P1, the operator can clearly determine that the movement is complete from a feeling received by their hand as the retaining protrusion 44 is inserted into the retaining recess 38.
[0123] In the present embodiment, the first contacting portion 40a includes the curved face 43 at the end portion facing the bottom apron belt 57. When the spring clip 40 is at the regulatory position P1, the curved face 43 contacts with the bottom apron belt 57 and moves the bottom apron belt 57.
[0124] Accordingly, the curved face 43, which is formed not to be sharp, contacts with the bottom apron belt 57 and traverses the bottom apron belt 57. Therefore, the bottom apron belt 57 can be prevented from being damaged.
[0125] In the present embodiment, the second contacting portion 40b includes the tapered portion 46 that increases its distance from the arm member 85 as it approaches the end portion facing the bottom apron belt 57. When the spring clip 40 at the regulatory position P1 is in contact with the bottom apron belt 57, the tapered portion 46 is spaced apart from the bottom apron belt 57.
[0126] Accordingly, the spring clip 40 can be easily attached to the arm member 85 during manufacture of the drafting apparatus 5 by utilizing the tapered portion 46. Since the tapered portion 46 does not contact with the bottom apron belt 57 during the traverse, the bottom apron belt 57 can be prevented from being damaged.
[0127] In the drafting apparatus 5 of the present embodiment, the first guiding recess 41 and the second guiding recess 42 are formed at the spring clip 40. The first guiding recess 41 includes a portion that is parallel to the upward direction D2. The second guiding recess 42 includes a portion that is parallel to the upward direction D2. The arm member 85 includes the first guiding protrusion 36 and the second guiding protrusion 37. The first guiding protrusion 36 can perform relative movement along the first guiding recess 41. The second guiding protrusion 37 can perform relative movement along the second guiding recess 42. When the spring clip 40 at the regulatory position P1 is viewed along the upward direction D2, the bent portion 45 that is convex to the arm member 85 is formed at at least one of the first contacting portion 40a or the second contacting portion 40b. When the spring clip 40 at the regulatory position P1 is viewed along the upward direction D2, the position CP1 at which the bent portion 45 contacts with the arm member 85 is located between the center of the first guiding protrusion 36 and the center of the second guiding protrusion 37 in the apron traverse direction D1.
[0128] Accordingly, the spring clip 40 can be stably attached to the arm member 85 since the force exerted by the spring clip 40 against the arm member 85 in order to sandwich it is unlikely to be transmitted unevenly.
[0129] In the drafting apparatus 5 of the present embodiment, when viewed along the apron traverse direction D1, the relative protrusion distance L1 or L2, which is a relative distance for which the first contacting portion 40a or the second contacting portion 40b protrudes in the upward direction D2 from its intersection with the traveling path of the bottom apron belt 57, is different between the first contacting portion 40a and the second contacting portion 40b. The first contacting portion 40a, whose relative protrusion distance is larger among the first contacting portion 40a and the second contacting portion 40b, contacts the bottom apron belt 57 and moves the bottom apron belt 57.
[0130] Accordingly, stable traverse of the bottom apron belt 57 can be achieved since the first contacting portion 40a that can effectively regulate for a longer length moves the bottom apron belt 57.
[0131] Next, a variation will be described below. In the description of the present variation, components identical or similar to those of the above-described embodiment may be marked with the same reference signs in the drawings and the description thereof may be omitted.
[0132] The drafting apparatus 5 may include an arm member 85x shown in FIG. 10 instead of the above-described spring clip 40. A regulatory member 40x is rotatably attached with respect to the arm member 85x with a hinge 95. The arm member 85x and the regulatory member 40x are plate-shaped members comprised of, for example, metal. Unlike the above-described spring clip 40, the regulatory member 40x does not include spring properties.
[0133] The regulatory member 40x can move between a regulatory position P1 shown in solid lines in FIG. 10 and a retracted position P2 shown in chained lines by rotating with a hinge shaft as the center. In the variation shown in FIG. 10, the hinge shaft is arranged parallel to the apron traverse direction D1. However, it is not limited to this. The range of the rotational angle of the regulatory member 40x is configured to be substantially 180 degree in the example shown in FIG. 10. However, it is not limited to this and it may be, for example, 90 degree.
[0134] In the variation shown in FIG. 10, when the arm member 85x traverses a bottom apron belt 57, the regulatory member 40x is fixed by suitable means so that it will not move from the regulatory position P1. The means for fixing may be, for example, pins, screws, clips, or magnets, but it is not limited to them.
[0135] Instead of connecting the regulatory member 40x to the arm member 85x by the hinge 95, the regulatory member 40x may be configured to be attachable to and detachable from the arm member 85x. The means for detachably attaching the regulatory member 40x to the arm member 85x may be, for example, screws or magnets, but it is not limited to them.
[0136] Although the preferred embodiment and variation have been described above, the above-described configurations can be modified, for example, as follows. Such a modification may be made singularly or made in combination with any other modification.
[0137] The shapes of the first guiding recess 41 and the second guiding recess 42 may be modified as desired. For example, the spring clip 40 may be configured to move from the regulatory position P1 to the retracted position P2 only by parallel movement or may be configured to move from the regulatory position P1 to the retracted position P2 only by rotation with the first guiding protrusion 36 as the center. The longitudinal direction of the first guiding recess 41 (the longitudinal direction of the first guiding portion 42a that the second guiding recess 42 includes) may be inclined with respect to the upward direction D2. At least one of the first guiding recess 41 or the second guiding recess 42 may be formed as a non-through groove.
[0138] The configuration, wherein the first guiding recess 41 and the second guiding recess 42 are formed at the arm member 85, while the first guiding protrusion 36 and the second guiding protrusion 37 are formed at the spring clip 40, may be employed.
[0139] The configuration also may be so modified that the retaining protrusion 44 is formed at the arm member 85 and the retaining recess 38 is formed at the spring clip 40. The retaining protrusion 44 and the bent portion 45 may be omitted.
[0140] The spring clip 40 may be so arranged that the connecting portion 40c is on the side closer to the bottom apron belt 57 (the support side S2). In this case, the arc-shaped face that the connecting portion 40c includes contacts with the bottom apron belt 57 and moves the bottom apron belt 57.
[0141] The curved face 43 may be arranged at the second contacting portion 40b instead of at the first contacting portion 40a or in addition to at the first contacting portion 40a. If the thickness of the metal plate member that comprises the spring clip 40 is sufficiently large, for example, the process of processing the spring clip 40 to curve it into a cylindrical shape to form the curved face 43 may be omitted.
[0142] The tapered portion 46 may be arranged at the first contacting portion 40a instead of at the second contacting portion 40b or in addition to at the second contacting portion 40b. For example, the tapered portion 46 may be arranged at the first contacting portion 40a and the curved face 43 may be formed at the end portion of the tapered portion 46. The spring clip 40 may also be configured without the tapered portion 46.
[0143] The bent portion 45 may be arranged at the first contacting portion 40a instead of at the second contacting portion 40b or in addition to at the second contacting portion 40b.
[0144] The components, such as the protruding portion 35 and the inclined protrusion 39, may be configured as components separated from the arm member 85. The inclined protrusion 39 may be omitted.
[0145] Instead of the cam mechanism, the reciprocating motion of the arm member 85 may be achieved by a rack-and-pinion mechanism, for example.
[0146] The apron traverse apparatus 84 may be used in order to traverse the top apron belt 77. In this case, the configuration may be as follows: the arm member 85 is arranged above the top apron belt 77 and the protruding portion 35 and the spring clip 40 protrude downwardly from the arm member 85.
, Claims:We claim:

1. A drafting apparatus (5) that drafts a fiber bundle (10), comprising:
an apron belt (57) that runs cyclically while keeping contact with the fiber bundle (10);
a guide (85) that guides the apron belt (57) so that the apron belt (57) traverses; and
a drive (86) that drives the guide (85) in a first direction (D1),
wherein the guide (85) includes:
a protruding portion (35) that protrudes in a second direction (D2) that is a different direction from the first direction (D1) and moves the apron belt (57) along the first direction (D1); and
a regulatory portion (40) that moves the apron belt (57) along the first direction (D1) in a direction opposite to a direction in which the protruding portion (35) moves the apron belt (57), and
wherein the regulatory portion (40) can perform movement relative to the protruding portion (35) between
a first position (P1) at which the apron belt (57) is prevented from coming off from a space between the regulatory portion (40) and the protruding portion (35) in the first direction (D1) and
a second position (P2) at which the apron belt (57) is allowed to come off from the space between the regulatory portion (40) and the protruding portion (35) in the first direction (D1), and
wherein, when the regulatory portion (40) is at the first position (P1), the regulatory portion (40) is located at an opposite side with respect to the protruding portion (35) in the first direction (D1) with the apron belt (57) located between the regulatory portion (40) and the protruding portion (35).

2. The drafting apparatus (5) as claimed in claim 1, wherein the regulatory portion (40) can perform relative movement between the first position (P1) and the second position (P2) while remaining attached to the guide (85).
3. The drafting apparatus (5) as claimed in claim 2, wherein the regulatory portion (40) is so arranged that it is rotatable about an axis in a third direction (D3) that is orthogonal to the first direction (D1) and the second direction (D2), and
wherein, in a process of the relative movement of the regulatory portion (40) between the first position (P1) and the second position (P2), the regulatory portion (40) rotates.

4. The drafting apparatus (5) as claimed in one of claims 1 to 3, wherein the regulatory portion (40) is attached in such a way that the regulatory portion (40) is movable with respect to the guide (85) in a direction parallel to the second direction (D2), and
wherein, in a process of relative movement of the regulatory portion (40) between the first position (P1) and the second position (P2), the regulatory portion (40) moves parallel to the second direction (D2).

5. The drafting apparatus (5) as claimed in claim 3 or 4, wherein a first guiding recess (41) and a second guiding recess (42) are formed at one of the regulatory portion (40) and the guide (85), and
wherein the guiding recess (41) includes a portion that is parallel to the second direction (D2), and
wherein the second guiding recess (42) includes a first guiding portion (42a) that is parallel to the second direction (D2) and a second guiding portion (42b) that is substantially arc-shaped, and
wherein another of the regulatory portion (40) and the guide (85) includes:
a first protrusion (36) that can perform relative movement along the first guiding recess (41); and
a second protrusion (37) that can perform relative movement along the second guiding recess (42), and
wherein, in the process of the relative movement of regulatory portion (40) between the first position (P1) and the second position (P2), movement along a longitudinal direction of the first guiding portion (42a) and rotation about a center of an arc of the second guiding portion (42b) are performed.

6. The drafting apparatus (5) as claimed in one of claims 1 to 5, wherein the regulatory portion (40) is comprised of an elastically deformable member that is separate from the guide (85), and
wherein the regulatory portion (40) includes:
a first contacting portion (40a) that contacts with the guide (85) from one side in a third direction (D3) that is orthogonal to the first direction (D1) and the second direction (D2);
a second contacting portion (40b) that contacts with the guide (85) from a side opposite to the one side from which the first contacting portion (40a) contacts in the third direction (D3); and
a connecting portion (40c) that connects the first contacting portion (40a) and the second contacting portion (40b), and
wherein the regulatory portion (40) sandwiches the guide (85) between the first contacting portion (40a) and the second contacting portion (40b) while being elastically deformed.

7. The drafting apparatus (5) as claimed in claim 6, wherein a retaining protrusion (44) is arranged at at least one of the guide (85) or the regulatory portion (40) and a retaining recess (38) is arranged at another of the guide (85) and the regulatory portion (40), and
wherein, when the regulatory portion (40) is at the first position (P1), the retaining protrusion (44) is inserted into the retaining recess (38).

8. The drafting apparatus (5) as claimed in claim 6 or 7, wherein at least one of the first contacting portion (40a) or the second contacting portion (40b) includes a curved face (43) at an end portion facing the apron belt (57), and
wherein, when the regulatory portion (40) is at the first position (P1), the curved face (43) prevents the apron belt (57) from coming off from the space between the regulatory portion (40) and the protruding portion (35) in the first direction (D1).

9. The drafting apparatus (5) as claimed in one of claims 6 to 8, wherein at least one of the first contacting portion (40a) or the second contacting portion (40b) includes a tapered portion (46) that increases its distance from the guide (85) as it approaches an end portion facing the apron belt (57) in the first direction (D1), and
wherein, when the regulatory portion (40) at the first position (P1) is in contact with the apron belt (57), the tapered portion (46) is spaced apart from the apron belt (57).

10. The drafting apparatus (5) as claimed in one of claims 6 to 9, wherein a first guiding recess (41) and a second guiding recess (42) are formed at one of the regulatory portion (40) and the guide (85), and
wherein the first guiding recess (41) includes a portion that is parallel to the second direction (D2), and
wherein the second guiding recess (42) includes a portion that is parallel to the second direction (D2), and
wherein another of the regulatory portion (40) and the guide (85) includes:
a first protrusion (36) that can perform relative movement along the first guiding recess (41); and
a second protrusion (37) that can perform relative movement along the second guiding recess (42), and
wherein, when the regulatory portion (40) at the first position (P1) is viewed along the second direction (D2), a bent portion (45) that is convex to the guide (85) is formed at at least one of the first contacting portion (40a) or the second contacting portion (40b), and
wherein, when the regulatory portion (40) at the first position (P1) is viewed along the second direction (D2), a position (CP1) at which the bent portion (45) contacts with the guide (85) is located between a center of the first protrusion (36) and a center of the second protrusion (37) in the first direction (D1).

11. The drafting apparatus (5) as claimed in one of claims 6 to 10, wherein, when viewed along the first direction (D1), a relative protrusion distance (L1, L2), which is a relative distance for which the first contacting portion (40a) or the second contacting portion (40b) protrudes in the second direction (D2) from its intersection with a traveling path of the apron belt (57), is different between the first contacting portion (40a) and the second contacting portion (40b), and
wherein, when the regulatory portion (40) is at the first position (P1), one of the first contacting portion (40a) and the second contacting portion (40b) whose relative protrusion distance (L1, L2) is larger prevents the apron belt (57) from coming off from the space between the regulatory portion (40) and the protruding portion (35) in the first direction (D1).