A pull chain clip mechanism with a taper lead-in
By using a tapered guide and chain-driven wire clamp mechanism, the problems of aligning metal wires with the threading holes and the belt's tendency to get dirty are solved, enabling fast and accurate metal wire operation and an efficient workflow.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUZHOU ZHICHUAN TECH CO LTD
- Filing Date
- 2025-06-06
- Publication Date
- 2026-06-16
AI Technical Summary
Existing metal wires are difficult to align accurately with the wire threading holes during electrical discharge machining, and the belts are not resistant to dirt, resulting in cumbersome operation and low work efficiency.
The wire clamp mechanism with tapered guide and chain is adopted, including a sliding wire clamp device and a chain device. The design of the tapered guide block with inclined guide surface and driven chain simplifies the wire threading and pulling process.
It enables fast and accurate threading and pulling of metal wires, improving work efficiency, and the driven chain is dirt-resistant and suitable for various applications.
Smart Images
Figure CN224359474U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of metal wire cutting equipment. Background Technology
[0002] In electrical discharge machining (EDM), moving wire electrode cutting is the most widely used. The cutting wire used in wire electrode cutting is an electrode wire (metal wire). In current equipment, the metal wire is wound around a drum. Before winding the metal wire onto the drum, it needs to be "threaded" and "pulled." "Threading" requires inserting the metal wire into the threading hole. Because the diameter of the threading hole is very small, it is difficult to align it, making the operation cumbersome, inefficient, and time-consuming. "Pulling" requires pulling the clamped metal wire to the next position. This pulling requires a belt, but belts are prone to getting dirty and are unsuitable in many situations. Summary of the Invention
[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of existing metal wires being difficult to align with the threading holes and belts being not resistant to dirt. It proposes a wire clamp mechanism with a tapered guide and chain, which is simple and easy to operate, accurate and fast in threading, improves work efficiency, is dirt resistant, and can be adapted to all application occasions.
[0004] In order to solve the above-mentioned technical problems, the present invention proposes the following technical solution: a cable clamp mechanism with tapered guide and chain, which includes a lower cable frame arranged in the left and right direction, a left end gear set mounting seat, a right end gear set mounting seat, a chain device and a slidable cable clamp device;
[0005] The left-end gear set mounting base and the right-end gear set mounting base are respectively installed and fixed on the left and right ends of the lower wire frame;
[0006] The chain device includes a left-end gear set, a right-end gear set, a driven chain, a chain drive motor, a drive gear, and a drive chain;
[0007] The left-end gear set is rotatably mounted between the rear end and the front end of the left-end gear set mounting base;
[0008] The right-end gear set is rotatably mounted between the rear end and the front end of the right-end gear set mounting base;
[0009] The left and right ends of the driven chain are respectively mounted on the left end gear set and the right end gear set;
[0010] The chain drive motor includes a rotating shaft;
[0011] The drive gear is mounted and fixed on the rotating shaft;
[0012] One end of the drive chain is mounted on the left gear set, and the other end is mounted on the drive gear.
[0013] The rotation of the rotating shaft drives the drive gear to rotate, which in turn pulls the drive chain to move. This drives the left-end gear set to rotate, and then drives the driven chain to move.
[0014] The sliding wire clamp device includes at least two sliding rods, a sliding base plate, a wire clamping and fixing block, and a tapered wire block;
[0015] The left and right ends of at least two slide rods are respectively installed and fixed in the left gear set mounting base and the right gear set mounting base, and the at least two slide rods are arranged in parallel along the left and right direction;
[0016] The sliding base plate is slidably mounted on at least two sliding rods and can slide in the left and right directions;
[0017] The driven chain is installed and fixed to the bottom surface of the sliding base plate;
[0018] The clamping fixing block is indirectly installed and fixed on the sliding base plate;
[0019] The tapered conductor block is installed and fixed on the wire clamping block. A wire hole is opened on the tapered conductor block, and an inclined conductor surface is provided around the wire hole.
[0020] A further limitation of the above technical solution is that the inclined guide surface is conical or square-pyramidal.
[0021] A further limitation of the above technical solution is that the sliding wire clamp device also includes a slider mounting block, a left and right drive device, a left and right sliding block, a connecting transmission rod, an up and down sliding wire clamping block, and a slider mounting block sealing plate;
[0022] The slider mounting block is fixed on the top surface of the sliding base plate. The inside of the slider mounting block has left and right sliding grooves and up and down sliding grooves from right to left.
[0023] The left and right drive devices are motors or cylinders, which are mounted and fixed on the right wall of the slider mounting block;
[0024] The left and right sliding blocks are placed in the left and right sliding slots of the slider mounting block and can slide left and right within them;
[0025] The left and right drive devices are connected to the left and right sliding blocks and push them to slide in the left and right directions;
[0026] The connecting transmission rod is in the shape of a "U". Its middle bent part is rotatably pivoted in the slider mounting block, its right end is rotatably pivoted in the left end of the left and right sliding blocks, and its left end is rotatably pivoted in the upper part of the upper and lower sliding clamping blocks.
[0027] The sliding clamping block is placed in the upper and lower sliding grooves of the slider mounting block and can slide up and down within it;
[0028] The top of the sliding wire clamping block has an upward-protruding wire clamping protrusion;
[0029] The wire clamping fixing block is installed and fixed on the top surface of the slider mounting block, and a wire clamping groove for accommodating the wire clamping protrusion is opened at the left end of the wire clamping fixing block;
[0030] The tapered conductor block is installed and fixed on the wire clamping fixing block and located on the right side of the wire clamping groove.
[0031] The slider mounting block sealing plate is fixed on the left side of the slider mounting block, encapsulating the left and right sliding blocks, connecting transmission rods, and up and down sliding clamping blocks inside the slider mounting block.
[0032] A further limitation of the above technical solution is that the sliding base plate has two through holes for sliding rods running in the left-right direction; there are at least two sliding rods, which are inserted into the two through holes respectively, and the sliding base plate can slide on the two sliding rods in the left-right direction.
[0033] A further limitation of the above technical solution is that the slidable cable clamp device also includes a driven chain fixing block, which installs and fixes the driven chain to the bottom surface of the sliding base plate.
[0034] A further limitation of the above technical solution is that the rear end and front end of the left gear set mounting base are respectively provided with a left rear bearing mounting base and a left front bearing mounting base; the left gear set includes a left gear mounting shaft arranged along the front-rear direction and a left rear bearing, a left rear gear, a left front gear, and a left front bearing that are sequentially mounted and fixed on the left gear mounting shaft from back to front; the left rear bearing and the left front bearing are respectively installed in the left rear bearing mounting base and the left front bearing mounting base;
[0035] The rear end and front end of the right gear set mounting base are respectively provided with a right rear bearing mounting base and a right front bearing mounting base; the right gear set includes a right gear mounting shaft arranged along the front-rear direction and a right rear bearing, a right front gear, and a right front bearing that are installed and fixed on the right gear mounting shaft from back to front; the right rear bearing and the right front bearing are respectively installed in the right rear bearing mounting base and the right front bearing mounting base;
[0036] The left and right ends of the driven chain are respectively mounted on the left front gear and the right front gear;
[0037] The left and right ends of the drive chain are respectively mounted on the left rear gear and the drive gear;
[0038] The rotation of the rotating shaft drives the drive gear to rotate. The rotation of the drive gear pulls the drive chain to move, which in turn drives the left rear gear to rotate. This, in turn, drives the left end gear mounting shaft and the left front gear to rotate. The rotation of the left front gear drives the driven chain to move.
[0039] A further limitation of the above technical solution is that the chain device also includes a motor mounting base plate and a motor mounting upright plate. The motor mounting base plate is fixedly mounted on the bottom of the lower frame, the motor mounting upright plate is fixedly mounted on the rear end of the motor mounting base plate, and the chain drive motor is fixedly mounted on the rear side wall of the motor mounting upright plate.
[0040] Compared with the prior art, the present invention has the following beneficial effects:
[0041] 1. The tapered wire block has a tapered or square-to-conical inclined wire surface around the wire hole, which makes it very easy and convenient to thread the metal wire into the wire hole along the inclined wire surface. The operation is simple and easy, the wire threading is accurate and fast, and the work efficiency is improved.
[0042] 2. Both driven and driving chains are dirt-resistant, have a long mechanical life, and are suitable for all applications. Attached Figure Description
[0043] Figure 1 This is a three-dimensional assembly diagram of the pull-line clamp mechanism with tapered guide and chain of this utility model.
[0044] Figure 2 This is an exploded view of the pull-wire clamp mechanism with tapered guide and chain of this utility model.
[0045] Figure 3 This is a perspective view of some components of the sliding pull-wire clamp device of this utility model.
[0046] Figure 4 This is a perspective view of the tapered guide block of this utility model.
[0047] Figure 5 This is a perspective view of the slider mounting block of this utility model.
[0048] Figure 6 This is a perspective view of the sliding wire clamping block and the wire clamping fixing block of this utility model.
[0049] Figure 7 This is a perspective view of the tapered guide block according to the second embodiment of this utility model. Detailed Implementation
[0050] To make the technical means, creative features, and achieved objectives and effects of this utility model easier to understand, the present utility model is further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are merely preferred embodiments of this utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments described in the implementation details without creative effort are all within the protection scope of this invention.
[0051] Please see Figures 1 to 6This utility model proposes a cable clamp mechanism with tapered guide and chain, which includes a lower cable frame 1, a left end gear set mounting seat 2, a right end gear set mounting seat 3, a chain device (unlabeled) and a sliding cable clamp device 5.
[0052] The lower frame 1 is set along the left and right direction.
[0053] The left gear set mounting base 2 and the right gear set mounting base 3 are respectively installed and fixed on the left and right ends of the lower wire frame 1.
[0054] The rear end and front end of the left gear set mounting base 2 are respectively provided with a left rear bearing mounting base 21 and a left front bearing mounting base 22.
[0055] The rear end and front end of the right gear set mounting base 3 are respectively provided with a right rear bearing mounting base 31 and a right front bearing mounting base 32.
[0056] The chain assembly (unnumbered) includes a left-end gear set (unnumbered), a right-end gear set (unnumbered), a driven chain 43, a motor mounting base plate 44, a motor mounting stand plate 45, a chain drive motor 46, a drive gear 47, and a drive chain 48.
[0057] The left-end gear set (unnumbered) and the right-end gear set (unnumbered) are respectively installed in the left-end gear set mounting base 2 and the right-end gear set mounting base 3.
[0058] The left-end gear set (unnumbered) includes a left-end gear mounting shaft 411 arranged along the front-back direction, and a left rear bearing 412, a left rear gear 413, a left front gear 414, and a left front bearing 415 that are sequentially mounted and fixed on the left-end gear mounting shaft 411 from back to front.
[0059] The left rear bearing 412 and the left front bearing 415 are respectively installed in the left rear bearing mounting base 21 and the left front bearing mounting base 22.
[0060] The right-end gear set (unnumbered) includes a right-end gear mounting shaft 421 arranged along the front-rear direction, and a right rear bearing 422, a right front gear 424, and a right front bearing 425 that are sequentially mounted and fixed on the right-end gear mounting shaft 421 from back to front.
[0061] The right rear bearing 422 and the right front bearing 425 are respectively installed in the right rear bearing mounting base 31 and the right front bearing mounting base 32.
[0062] The left and right ends of the driven chain 43 are respectively mounted on the left front gear 414 and the right front gear 424.
[0063] The motor mounting base plate 44 is installed and fixed at the bottom of the lower frame 1.
[0064] The motor mounting plate 45 is mounted and fixed to the rear end of the motor mounting base plate 44.
[0065] The chain drive motor 46 is mounted and fixed on the rear side wall of the motor mounting plate 45, and includes a rotating shaft 462.
[0066] The drive gear 47 is mounted and fixed on the rotating shaft 462.
[0067] The left and right ends of the drive chain 48 are respectively mounted on the left rear gear 413 and the drive gear 47.
[0068] Start the chain drive motor 46, the rotating shaft 462 rotates and drives the drive gear 47 to rotate. The rotation of the drive gear 47 pulls the drive chain 48 to move and drives the left rear gear 413 to rotate, thereby driving the left end gear mounting shaft 411 and the left front gear 414 to rotate. The rotation of the left front gear 414 drives the driven chain 43 to move.
[0069] The sliding cable clamp device 5 includes two parallel sliding rods 51 arranged along the left and right directions, a sliding base plate 52, a driven chain fixing block 53, a slider mounting block 54, a left and right drive device 55, a left and right sliding block 56, a connecting transmission rod 57, an up and down sliding cable clamping block 58, a cable clamping fixing block 59, a tapered wire guide block 60, and a slider mounting block sealing plate 61.
[0070] The left and right ends of the two slide rods 51 are respectively installed and fixed in the left gear set mounting seat 2 and the right gear set mounting seat 3.
[0071] The sliding base plate 52 has two through holes 521 extending in the left-right direction. Two slide rods 51 are inserted into the two through holes 521 respectively, and the sliding base plate 52 can slide in the left-right direction on the two slide rods 51.
[0072] Driven chain fixing block 53 installs and fixes driven chain 43 to the bottom surface of sliding base plate 52.
[0073] The slider mounting block 54 is mounted and fixed on the top surface of the sliding base plate 52. The interior of the slider mounting block 54 has left and right sliding grooves 541 and up and down sliding grooves 542, which are opened sequentially from right to left.
[0074] The left and right drive devices 55 are motors or cylinders, which are mounted and fixed on the right wall of the slider mounting block 54.
[0075] The left and right sliding block 56 is placed in the left and right sliding groove 541 of the slider mounting block 54 and can slide left and right therein.
[0076] The left and right drive device 55 is connected to the left and right sliding block 56 and pushes it to slide in the left and right direction.
[0077] The connecting transmission rod 57 is shaped like the number 7. Its middle bent part is rotatably pivoted in the slider mounting block 54, its right end is rotatably pivoted in the left end of the left and right sliding blocks 56, and its left end is rotatably pivoted in the upper part of the upper and lower sliding clamping blocks 58.
[0078] The vertical sliding clamping block 58 is placed in the vertical sliding groove 542 of the slider mounting block 54 and can slide up and down therein.
[0079] A wire clamping protrusion 582 protrudes upward from the top of the sliding wire clamping block 58.
[0080] The wire clamping fixing block 59 is mounted and fixed on the top surface of the slider mounting block 54. The left end of the wire clamping fixing block 59 has a wire clamping groove 592 for accommodating the wire clamping protrusion 582.
[0081] The tapered conductor block 60 is mounted and fixed on the wire clamping block 59 and located on the right side of the wire clamping groove 592. A wire-passing hole 601 is opened in the center of the tapered conductor block 60, and a conical inclined conductor surface 603 is opened around the wire-passing hole 601. The function of the inclined conductor surface 603 is that when the metal wire (not shown) comes into contact with the inclined conductor surface 603, it follows the inclined conductor surface 603 and enters the wire-passing hole 601 very easily and conveniently.
[0082] The slider mounting block sealing plate 61 is installed and fixed on the left side of the slider mounting block 54, and the left and right sliding blocks 56, the connecting transmission rod 57 and the up and down sliding clamping block 58 are all encapsulated inside the slider mounting block 54.
[0083] When a metal wire (not shown) needs to be pulled, first thread the metal wire through the wire hole 601 of the tapered wire block 60. The metal wire enters the wire clamping groove 592 and is positioned above the wire clamping protrusion 582. Then, activate the left and right drive device 55, pushing the left and right sliding blocks 56 to slide to the left, causing the connecting transmission rod 57 to rotate clockwise around its central bend. The left end of the connecting transmission rod 57 moves upward, pushing the upper and lower sliding wire clamping blocks 58 to slide upward. The wire clamping protrusion 582 inserts into the wire clamping groove 592, clamping the metal wire (not shown). Finally, activate the chain drive motor 46. The rotating shaft 462 rotates, driving the drive gear 47 to rotate. The rotation of the drive gear 47 pulls the drive chain 48, which in turn drives the left rear gear 413 to rotate, thereby driving the left end gear mounting shaft 411 and the left front gear 414 to rotate. The rotation of the left front gear 414 drives the driven chain 43 to move counterclockwise. This causes the sliding base plate 52 and the sliding wire clamp device 5 to slide along the left, thereby pulling the metal wire to the left and completing the wire drawing work.
[0084] To release the wire, simply activate the left and right drive mechanism 55, pull the left and right sliding blocks 56 to slide to the right, pull the connecting transmission rod 57 to rotate counterclockwise around its central bend, and move the left end of the connecting transmission rod 57 downwards, pulling the up and down sliding wire clamping block 58 downwards. The wire clamping protrusion 582 disengages from the wire clamping groove 592, thus releasing the wire.
[0085] This utility model has the following beneficial effects:
[0086] 1. The tapered wire block 60 has a conical inclined wire surface 603 around the wire hole 601, which makes it very easy and convenient to thread the metal wire (not shown) into the wire hole 601 along the inclined wire surface 603. The operation is simple and easy, the wire threading is accurate and fast, and the work efficiency is improved.
[0087] 2. The driven chain 43 and the driving chain 48 are dirt-resistant, have a long mechanical life, and are suitable for all applications.
[0088] In the second embodiment, as Figure 7 As shown, another tapered wire block 70, which replaces the tapered wire block 60, has a square pyramid-shaped inclined wire surface 703 around the wire hole 701. Its effect of guiding the metal wire (not shown) into the wire hole 701 is comparable to that of the tapered wire block 60 in the first embodiment.
[0089] In the third embodiment, the left end of the drive chain 48 is instead mounted on the drive gear 47 (not shown), and the right end is instead mounted on the left rear gear 413 of the left end gear set (not shown). In summary, combining the first embodiment, the same function and effect can be achieved by mounting one end of the drive chain 48 on the left end gear set and the other end on the drive gear 47.
[0090] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.
Claims
1. A wire clamp mechanism with a tapered guide and chain, characterized in that, It includes a lower wire frame (1) arranged along the left and right directions, a left-end gear set mounting base (2), a right-end gear set mounting base (3), a chain device, and a sliding wire clamp device (5); The left end gear set mounting seat (2) and the right end gear set mounting seat (3) are respectively installed and fixed on the left and right ends of the lower wire frame (1); The chain device includes a left-end gear set, a right-end gear set, a driven chain (43), a chain drive motor (46), a drive gear (47), and a drive chain (48). The left-end gear set is rotatably mounted between the rear end and the front end of the left-end gear set mounting base (2); The right-end gear set is rotatably mounted between the rear end and the front end of the right-end gear set mounting base (3); The left and right ends of the driven chain (43) are respectively mounted on the left end gear set and the right end gear set; The chain drive motor (46) includes a rotating shaft (462); The drive gear (47) is mounted and fixed on the rotating shaft (462); One end of the drive chain (48) is mounted on the left end gear set, and the other end is mounted on the drive gear (47); The rotating shaft (462) rotates, causing the driving gear (47) to rotate and pulling the driving chain (48) to move. Then it drives the left end gear set to rotate, and then drives the driven chain (43) to move. The sliding wire clamp device (5) includes at least two sliding rods (51), a sliding base plate (52), a wire clamping fixing block (59), and a tapered wire block (60); The left and right ends of at least two slide rods (51) are respectively installed and fixed in the left gear set mounting seat (2) and the right gear set mounting seat (3), and the at least two slide rods (51) are arranged in parallel along the left and right directions; The sliding base plate (52) is slidably mounted on at least two sliding rods (51) and can slide in the left and right directions; The driven chain (43) is installed and fixed to the bottom surface of the sliding base plate (52); The clamping fixing block (59) is indirectly installed and fixed on the sliding base plate (52); The tapered conductor block (60) is installed and fixed on the wire clamping block (59). A wire hole (601, 701) is opened on the tapered conductor block (60, 70), and an inclined conductor surface (603, 703) is provided around the wire hole (601, 701).
2. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The inclined guide planes (603, 703) are conical or square pyramidal in shape.
3. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The sliding wire clamp device (5) also includes a slider mounting block (54), a left and right drive device (55), a left and right sliding block (56), a connecting transmission rod (57), an up and down sliding wire clamping block (58), and a slider mounting block sealing plate (61). The slider mounting block (54) is mounted and fixed on the top surface of the sliding base plate (52). The slider mounting block (54) has left and right sliding grooves (541) and upper and lower sliding grooves (542) arranged from right to left. The left and right drive devices (55) are motors or cylinders, which are mounted and fixed on the right wall of the slider mounting block (54); The left and right sliding block (56) is placed in the left and right sliding groove (541) of the slider mounting block (54) and can slide left and right therein; The left and right drive device (55) is connected to the left and right sliding blocks (56) and pushes them to slide in the left and right direction; The connecting transmission rod (57) is 7-shaped, with its middle bend pivotally connected to the slider mounting block (54) in a rotatable manner. Its right end is pivotally connected to the left end of the left and right sliding blocks (56), and its left end is pivotally connected to the upper part of the upper and lower sliding clamping blocks (58). The sliding clamping block (58) is placed in the sliding groove (542) of the slider mounting block (54) and can slide up and down therein; A wire clamping protrusion (582) protrudes upward from the top of the sliding wire clamping block (58); The wire clamping fixing block (59) is installed and fixed on the top surface of the slider mounting block (54), and the left end of the wire clamping fixing block (59) is provided with a wire clamping groove (592) to accommodate the wire clamping protrusion (582). The tapered conductor blocks (60, 70) are installed and fixed on the wire clamping fixing block (59) and located on the right side of the wire clamping groove (592). The slider mounting block sealing plate (61) is installed and fixed on the left side of the slider mounting block (54), and the left and right sliding blocks (56), the connecting transmission rod (57) and the up and down sliding clamping block (58) are all encapsulated inside the slider mounting block (54).
4. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The sliding base plate (52) has two through holes (521) for sliding rods that run through the left and right directions; there are at least two sliding rods (51), which are inserted into the two through holes (521) respectively, and the sliding base plate (52) can slide on the two sliding rods (51) in the left and right directions.
5. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The sliding cable clamp device (5) also includes a driven chain fixing block (53), which fixes the driven chain (43) to the bottom surface of the sliding base plate (52).
6. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The rear end and front end of the left gear set mounting base (2) are respectively provided with a left rear bearing mounting base (21) and a left front bearing mounting base (22); the left gear set includes a left gear mounting shaft (411) arranged along the front-rear direction and a left rear bearing (412), a left rear gear (413), a left front gear (414) and a left front bearing (415) installed and fixed on the left gear mounting shaft (411) from back to front; the left rear bearing (412) and the left front bearing (415) are respectively installed in the left rear bearing mounting base (21) and the left front bearing mounting base (22); The rear end and front end of the right gear set mounting base (3) are respectively provided with a right rear bearing mounting base (31) and a right front bearing mounting base (32); the right gear set includes a right gear mounting shaft (421) arranged along the front-rear direction and a right rear bearing (422), a right front gear (424) and a right front bearing (425) installed and fixed on the right gear mounting shaft (421) from back to front; the right rear bearing (422) and the right front bearing (425) are respectively installed in the right rear bearing mounting base (31) and the right front bearing mounting base (32); The left and right ends of the driven chain (43) are respectively mounted on the left front gear (414) and the right front gear (424); The left and right ends of the drive chain (48) are respectively mounted on the left rear gear (413) and the drive gear (47), or the left and right ends of the drive chain (48) are respectively mounted on the drive gear (47) and the left rear gear (413); The rotating shaft (462) rotates, driving the drive gear (47) to rotate. The rotation of the drive gear (47) pulls the drive chain (48) to move, which in turn drives the left rear gear (413) to rotate, thereby driving the left end gear mounting shaft (411) and the left front gear (414) to rotate. The rotation of the left front gear (414) drives the driven chain (43) to move.
7. The wire clamp mechanism with tapered guide and chain according to claim 1, characterized in that, The chain device also includes a motor mounting base plate (44) and a motor mounting stand plate (45). The motor mounting base plate (44) is fixed to the bottom of the lower wire frame (1), and the motor mounting stand plate (45) is fixed to the rear end of the motor mounting base plate (44). The chain drive motor (46) is fixed to the rear side wall of the motor mounting stand plate (45).