A loading and unloading device for a transmission belt appearance defect detection equipment

Abstract

This invention discloses a loading and unloading device for a transmission belt appearance defect detection equipment, including a rotary loading device, a feeding mechanism, a material level detection mechanism, a tensioning mechanism, a moving receiving mechanism, and a unloading mechanism. The rotary loading device includes a base, a lower support column, and an upper support column. The lower support column is fixedly mounted on the base, and the upper support column is rotatably connected to the lower support column. The feeding mechanism includes a feeding frame, a feeding motor, a feeding slider, a feeding slide rail, a material level detection switch, a feeding slider, a feeding slide rail, a feeding telescopic rod, a material level detection rotating block, and a light spring. The feeding slide rail is mounted on the feeding frame, and the feeding slider is slidably connected to the feeding slide rail. The feeding motor is mounted on the feeding frame, and a sprocket is mounted on the feeding frame. A sprocket is also mounted on the output shaft of the feeding motor. The beneficial effects of this invention are: it can achieve semi-automatic loading and unloading, partially replacing manual labor and reducing labor intensity.

Description

Technical Field

[0001] This invention belongs to the technical field of transmission belt testing equipment, specifically relating to loading and unloading devices. Background Technology

[0002] Mechanical transmission is a crucial component of industrial infrastructure. Common mechanical transmission mechanisms include gear drives, belt drives, chain drives, and continuously variable transmissions (CVTs). In terms of economy and ease of operation, belt drives are the most competitive transmission method. The practical application of belt drives is to transmit the power or motion generated by the rotation of an electric motor or engine to mechanical equipment. Belt drives are used in everything from giant motors with thousands of kilowatts to micro-motors with less than a few watts or even microwatts, and in everything from general machinery to automated equipment. Statistics show that in transmission systems where an electric motor is the power input, belt drives are used in 50% to 60% of the primary transmission stages. With advancements in belt drive technology, they are also gradually being applied in precision transmission fields, including 3D printers and robots.

[0003] In the entire manufacturing process of transmission belts, there are multiple inspection stages, with the final product inspection being the most crucial, determining the quality of the final product. Currently, the final stage of transmission belt surface defect detection mostly relies on manual inspection. To address this issue, an automatic transmission belt surface defect detection device has been developed, and a matching transmission belt loading and unloading mechanism has been designed into this device. Summary of the Invention

[0004] To address the problem that there is no matching loading and unloading mechanism for transmission belts in the existing technology, a loading and unloading device for a transmission belt appearance defect detection equipment is provided.

[0005] A loading and unloading device for a transmission belt appearance defect detection equipment.

[0006] Includes a rotary feeding device, a feeding mechanism, a material level detection mechanism, a tensioning mechanism, a moving receiving mechanism, and a discharging mechanism;

[0007] The rotary feeding device includes a base, a lower support column, and an upper support column;

[0008] The lower support column is fixedly mounted on the base, and the upper support column is rotatably connected to the lower support column.

[0009] The feeding mechanism includes a feeding frame, a feeding motor, a feeding slider, a feeding slide, a material level detection switch, a feeding slider, a feeding slide rail, a feeding telescopic rod, a material level detection rotating block, and a light spring;

[0010] The feeding slide is set on the feeding frame, the feeding slider is slidably connected to the feeding slide, the feeding motor is set on the feeding frame, a sprocket is set on the feeding frame, a sprocket is set on the output shaft of the feeding motor, and a chain is set on the two sprockets. The chain and the feeding slider are fixedly connected. The feeding motor drives the feeding slider to slide forward or backward on the feeding slide in both forward and reverse directions.

[0011] The material level detection rotating block includes a lever, rotating block, rotating shaft, detection counterweight, and bearing;

[0012] The rotating shaft is mounted on the feeding frame and located below the front end of the feeding slide. The bearing is mounted on the rotating shaft, and the rotating block is mounted on the bearing. A lever is mounted on one end of the rotating block, and a detection counterweight is mounted on the other end.

[0013] The material level detection switch is installed on the feeding rack to sense and detect the counterweight;

[0014] The pusher cylinder is mounted on the feeding frame, and the rod end of the pusher cylinder is equipped with a feeding slider, which is slidably connected to the feeding slide rail.

[0015] The feeding slider has a through hole, with a smaller diameter at the front and a larger diameter at the rear. The telescopic rod has a baffle at its rear end. The telescopic rod is inserted into the through hole of the feeding slider. The baffle engages at the junction of the large and small holes to prevent the telescopic rod from sliding out from the front end. A light spring is installed in the large hole of the feeding slider. The other end of the light spring is pressed against the end face of the baffle of the telescopic rod. The rear end of the large hole of the feeding slider is sealed to block the rear end of the light spring.

[0016] The mobile receiving mechanism includes a mobile frame, a fixed frame, a ball screw drive mechanism, a slider guide mechanism, support legs, and a receiving motor.

[0017] The movable frame is slidably mounted on the fixed frame via a slider guide mechanism. The receiving motor is mounted on the fixed frame and drives the movable frame to slide left and right on the fixed frame via a ball screw drive mechanism.

[0018] The tensioning mechanism includes a tensioning frame, a tensioning motor, a large tensioning wheel, a small tensioning wheel, a side tensioning wheel, a dual-shaft cylinder, and a tensioning slider;

[0019] The tensioning frame is mounted on the movable frame, the tensioning slider is slidably mounted on the tensioning frame, the tensioning motor is mounted on the tensioning frame, and the tensioning motor drives the tensioning slider to slide up and down through a ball screw nut. The large tensioning wheel is fixedly mounted on the tensioning frame, and the small tensioning wheel is fixedly mounted on the tensioning slider.

[0020] The dual-axis cylinder is mounted on the moving frame, and a side tensioning wheel is installed at its extended rod end to tension the transmission belt from the side.

[0021] The feeding mechanism includes a retaining ring, a feeding lever, a feeding shaft, a rotating arm, a feeding bracket, a feeding cylinder, and a swing arm.

[0022] The feeding bracket is mounted on the movable frame, the feeding shaft is rotatably mounted on the feeding bracket, one end of the swing arm is connected to the feeding shaft, the other end of the swing arm is connected to the feeding lever, the retaining ring is set at the connection between the swing arm and the feeding lever, the tail end of the feeding cylinder is rotatably mounted on the movable frame, the rod end of the feeding cylinder is rotatably connected to the rotating arm, and the other end of the rotating arm is fixedly connected to the feeding shaft.

[0023] The material feeding auxiliary cylinder is mounted on the movable frame via a bracket, and the rod end of the material feeding auxiliary cylinder is connected to a push plate.

[0024] The loading and unloading device of the transmission belt appearance defect detection equipment further includes a first locking ring, a second locking ring, a first stop, a second stop, and a locking handle.

[0025] The first locking ring is fixedly installed on the lower support column by bolts and nuts, and the second locking ring is fixedly installed on the upper support column by bolts and nuts. The first stop block is fixedly set on the first locking ring, and the second stop block is fixedly set on the second locking ring. The front end of the locking handle is a screw rod. After passing through the holes of the first stop block and the second stop block, the nut is tightened to fix the two.

[0026] The conveyor belt appearance defect detection equipment includes a loading and unloading device and a loading mechanism, one set on each side, symmetrically arranged on both sides of the large tension wheel.

[0027] The loading and unloading device of the transmission belt appearance defect detection equipment also has two unloading auxiliary cylinders, one on the left and one on the right, located on both sides of the large tension wheel.

[0028] The beneficial effects of this invention are: it enables semi-automatic loading and unloading, partially replacing manual labor and reducing labor intensity. The transmission belts described in this invention include, but are not limited to, multi-ribbed belts, synchronous belts, V-belts, etc., used in transmission systems. Attached Figure Description

[0029] Figure 1 This is a structural schematic diagram of an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the rotating device of the present invention;

[0031] Figure 3 This is a schematic diagram of the feeding mechanism of the present invention;

[0032] Figure 4 This is a schematic diagram of the feeding mechanism of the present invention;

[0033] Figure 5 This is a schematic diagram of the material level detection mechanism of the present invention;

[0034] Figure 6 This is a schematic diagram of the telescopic rod of the present invention;

[0035] Figure 7 This is a schematic diagram of the feeding mechanism of the present invention;

[0036] Figure 8 This is a schematic diagram of the tensioning mechanism of the present invention;

[0037] Figure 9 This is a schematic diagram of the moving material receiving mechanism of the present invention;

[0038] Figure 10 This is a schematic diagram of the material feeding auxiliary mechanism of the present invention;

[0039] Figure 11 This is a schematic diagram of the rotary locking device of the present invention. Detailed Implementation

[0040] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0041] See Figures 1-10 This embodiment provides a loading and unloading device for a transmission belt appearance defect detection equipment.

[0042] like Figure 1 As shown, it includes a rotary feeding device 001, a feeding mechanism, a material level detection mechanism, a tensioning mechanism, a moving receiving mechanism, and a discharging mechanism.

[0043] The rotary feeding device 001 includes a base 101, a lower support column 102, an upper support column 105, a first locking ring 103, a second locking ring 104, a first stop block 108, a second stop block 109, and a locking handle 107.

[0044] The lower support column 102 is fixedly mounted on the base 101. The upper support column 105 is rotatably connected to the lower support column 102. The first locking ring 103 is fixedly mounted on the lower support column 105 by bolts and nuts. The second locking ring 104 is fixedly mounted on the upper support column 105 by bolts and nuts. The first stop block 108 is fixedly mounted on the first locking ring 103. The second stop block 109 is fixedly mounted on the second locking ring 104. The front end of the locking handle 107 is a screw. After passing through the holes of the first stop block 108 and the second stop block 109, the nut is tightened to fix the two.

[0045] The first stop 108 and the second stop 109 serve to limit the rotation during the process, allowing only a specific angle of 90 degrees to be rotated. Once in position, they are locked in place by the locking handle 107.

[0046] like Figure 1 As shown, during loading, the upper support column 105 rotates 90 degrees counterclockwise. At this time, the feeding mechanism is on the outside, and the worker places the transmission belt onto the feeding mechanism one by one. After manual loading is completed, the upper support column 105 rotates 90 degrees clockwise back to its original position. Figure 1 The machine automatically starts feeding materials at the designated location.

[0047] like Figure 3 , 4 As shown, the feeding mechanism includes a feeding frame 300, a feeding motor 301, a feeding slider 302, a feeding slide rail 303, a material level detection switch 304, a feeding slider 305, a feeding slide rail 306, a feeding telescopic rod 307, a material level detection rotating block 308, and a light spring 309.

[0048] The feeding slide 303 is set on the feeding frame 300. The feeding slider 302 is slidably connected to the feeding slide 303. The feeding motor 301 is set on the feeding frame 300. A sprocket is set on the feeding frame 300 and a sprocket is set on the feeding motor 301. A chain is set on the two sprockets. The chain and the feeding slider 302 are fixedly connected. The feeding motor 301 drives the feeding slider 302 to slide forward or backward on the feeding slide 303 in both directions.

[0049] like Figure 4 As shown, the transmission belts are hung one after another on the feeding slide 303. The feeding motor 301 rotates, driving the feeding slider 302 to push the transmission belts forward along the feeding slide 303.

[0050] The material level detection rotating block 308 includes a lever 3081, a rotating block 3082, a rotating shaft 3083, a detection counterweight 3084, and a bearing 3085.

[0051] A rotating shaft 3083 is mounted on the feeding frame 300 and located below the front end of the feeding chute 303. A bearing 3085 is mounted on the rotating shaft 3083, and a rotating block 3082 is mounted on the bearing 3085. A lever 3081 is mounted on one end of the rotating block, and a detection counterweight 3084 is mounted on the other end. A material level detection switch 304 is mounted on the feeding frame 300 to sense and detect the counterweight 3084.

[0052] like Figure 4 , 5As shown, the counterweight is quite heavy. Without a drive belt, the front lever 3081 tilts upwards. As the feeding motor 301 rotates, it feeds and pushes the drive belt. The drive belt slides from the feeding chute 303 onto the lever 3081. Under the weight of the drive belt, the rotating block 3082 rotates. The material level detection switch 304 detects the counterweight 3084 and receives a signal, instructing the feeding motor 301 to stop. The drive belt then falls onto the feeding telescopic rod 307.

[0053] like Figure 4 As shown, the pusher cylinder 002 is mounted on the feeder frame 300, and the rod end of the pusher cylinder 002 is provided with a feed slider 305, which is slidably connected to the feed rail 306.

[0054] like Figure 6 As shown, the feeding slider 305 has a through hole, with a smaller diameter at the front and a larger diameter at the rear. The telescopic rod 307 has a baffle at its rear end. The telescopic rod 307 is inserted into the through hole of the feeding slider 305, and the baffle engages at the junction of the large and small holes to prevent the telescopic rod 307 from sliding out from the front end. A light spring 309 is installed in the large hole of the feeding slider 305, and the other end of the light spring is pressed against the end face of the baffle of the telescopic rod 307. The rear end of the large hole of the feeding slider 305 is blocked, preventing the rear end of the light spring 309 from moving out.

[0055] When the front end of the telescopic rod 307 receives pressure, it will slide to the left, compressing the light spring. When there is no pressure, the light spring will spring the telescopic rod 307 back.

[0056] like Figure 9 As shown, the moving receiving mechanism includes a moving frame 601, a fixed frame 602, a ball screw drive mechanism 604, a slider guide mechanism 605, a support leg 606, and a receiving motor 007.

[0057] The movable frame 601 is slidably mounted on the fixed frame 602 via the slider guide mechanism 605. The receiving motor 007 is mounted on the fixed frame 602 and is driven by the ball screw drive mechanism 604 to slide left and right on the fixed frame 602.

[0058] like Figure 8 As shown, the tensioning mechanism includes a tensioning frame 500, a tensioning motor 501, a large tensioning wheel 502, a small tensioning wheel 503, a side tensioning wheel 504, a dual-shaft cylinder 506, and a tensioning slider 507.

[0059] The tensioning frame 500 is mounted on the movable frame 601. The tensioning slider 507 is slidably mounted on the tensioning frame 500. The tensioning motor 501 is mounted on the tensioning frame 500. The tensioning motor 501 drives the tensioning slider 507 to slide up and down through a ball screw nut. The large tensioning wheel 502 is fixedly mounted on the tensioning frame 500, and the small tensioning wheel 503 is fixedly mounted on the tensioning slider 507.

[0060] A dual-axis cylinder 506 is mounted on a movable frame 601, and a side tensioning wheel 504 is installed at its extended rod end. The transmission belt is tensioned from the side.

[0061] like Figure 9 As shown, after the pusher cylinder 002 extends, the receiving motor 007 of the moving receiving mechanism starts, sliding the moving frame 601 together with the tensioning mechanism to the left. The large tension wheel 502 moves towards the telescopic rod 307, which retracts due to compression. The upper edge of the large tension wheel 502 is slightly lower than the telescopic rod, and the transmission belt on the telescopic rod slides down onto the upper edge of the large tension wheel, completing the transmission belt receiving.

[0062] Then, driven by the tensioning motor 501, the small tensioning pulley 503 and the tensioning slider 507 slide downwards along the tensioning frame 500. As the small tensioning pulley 503 slides downwards, the transmission belt is tensioned on both the large and small tensioning pulleys. The dual-axis cylinder 506 extends, and the side tensioning pulley 504 presses the transmission belt from the side. After the moving receiving mechanism completes receiving the material, it moves to the right, and the transmission belt is inspected by the vision system. The feeding cylinder retracts, waiting for the next transmission belt. A drive motor is installed on the tensioning frame, driving the large tensioning pulley to rotate, and the transmission belt is inspected during this rotation. Because the camera is stationary, the transmission belt needs to be rotated.

[0063] The feeding mechanism includes a retaining ring 401, a feeding lever 402, a feeding shaft 403, a rotating arm 406, a feeding bracket 405, a feeding cylinder 404, and a swing arm 407.

[0064] The feeding bracket 405 is mounted on the movable frame 601. The feeding shaft 403 is rotatably mounted on the feeding bracket 405. One end of the swing rod 407 is connected to the feeding shaft 403, and the other end of the swing rod 407 is connected to the feeding lever 402. The retaining ring 401 is located at the connection between the swing rod 407 and the feeding lever 402. The tail end of the feeding cylinder 404 is rotatably mounted on the movable frame 601. The rod end of the feeding cylinder 405 is rotatably connected to the rotating arm 406, and the other end of the rotating arm 406 is fixedly connected to the feeding shaft 403.

[0065] The feeding auxiliary cylinder 702 is mounted on the movable frame 601 via a bracket 703, and the rod end of the feeding auxiliary cylinder 702 is connected to the push plate 703.

[0066] like Figure 1 As shown, there are two sets of feeding mechanisms, one on each side, symmetrically positioned on either side of the large tension wheel. The feeding shaft 403 is parallel to the shaft of the large tension wheel. When the feeding cylinder 404 retracts, it drives the shaft 403 to rotate, causing the feeding lever 402 to extend to the front end of the large tension wheel. The feeding lever points vertically towards the large tension wheel, ready to connect to the drive belt. The two sets on each side are for differentiation; one set is used when the product passes inspection, and the other set is used when it fails inspection, thus effectively classifying qualified and unqualified products.

[0067] There are also two feeding auxiliary cylinders 702, one on each side of the large tensioner. After the transmission belt detection is completed, the small tensioner slides upward, and the transmission belt loosens. At this time, the two feeding auxiliary cylinders 702 simultaneously push the transmission belt forward, causing the transmission belt to fall off and land on the feeding lever 402.

[0068] Then, the feeding cylinder 404 extends, causing the feeding shaft 403 to rotate counterclockwise. The lever moves away from the center position, pulling the transmission belt on the feeding lever 402 away from the outside of the equipment. During the rotation of the lever, the transmission belt will fall off the lever and into the receiving box.

[0069] To facilitate disengagement, the lever and the swing arm are at an obtuse angle. The retaining ring 401 prevents the drive belt from getting stuck at the connection point.

[0070] At this point, the cutting of one transmission belt is complete.

[0071] The vision system consists of line scan cameras, each mounted on a frame, which detect the outer and inner sides of the conveyor belt, respectively. There are many implementations of vision inspection systems; this application focuses on the loading and unloading process of the conveyor belt.

[0072] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "clockwise" and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0073] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above embodiments. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A loading and unloading device for a transmission belt appearance defect inspection equipment, characterized in that, Includes a rotary feeding device (001), a feeding mechanism, a material level detection mechanism, a tensioning mechanism, a moving receiving mechanism, and a discharging mechanism; The rotary feeding device (001) includes a base (101), a lower support column (102), and an upper support column (105); The lower support column (102) is fixedly mounted on the base (101), and the upper support column (105) is rotatably connected to the lower support column (102). The feeding mechanism includes a feeding frame (300), a feeding motor (301), a feeding sliding block (302), a feeding slide rail (303), a material level detection switch (304), a feeding slider (305), a feeding slide rail (306), a feeding telescopic rod (307), a material level detection rotating block (308), and a light spring (309); The feeding slide (303) is set on the feeding frame (300), the feeding sliding block (302) is slidably connected to the feeding slide (303) in the front and back, the feeding motor (301) is set on the feeding frame (300), a sprocket is set on the feeding frame (300), a sprocket is set on the output shaft of the feeding motor (301), a chain is set on the two sprockets, the chain and the feeding sliding block (302) are fixedly connected, the feeding motor (301) drives the feeding sliding block (302) to slide forward or backward on the feeding slide (303) in forward and reverse rotation; The material level detection rotating block (308) includes a lever (3081), a rotating block (3082), a rotating shaft (3083), a detection counterweight (3084), and a bearing (3085); The rotating shaft (3083) is mounted on the feeding rack (300) and located below the front end of the feeding slide (303). The bearing (3085) is mounted on the rotating shaft (3083), and the rotating block (3082) is mounted on the bearing (3085). One end of the rotating block is equipped with a lever (3081), and the other end is equipped with a detection counterweight (3084). A material level detection switch (304) is installed on the feeder (300) for sensing and detecting the counterweight (3084); The pusher cylinder (002) is mounted on the feeder (300), and the rod end of the pusher cylinder (002) is provided with a feed slider (305), which is slidably connected to the feed rail (306). The feeding slider (305) has a through hole, with a small diameter at the front and a large diameter at the rear. The telescopic rod (307) has a baffle at the rear end. The telescopic rod (307) is inserted into the through hole of the feeding slider (305). The baffle is engaged at the junction of the large and small holes to prevent the telescopic rod (307) from sliding out from the front end. A light spring (309) is installed in the large hole of the feeding slider (305). The other end of the light spring is pressed against the end face of the baffle of the telescopic rod (307). The rear end of the large hole of the feeding slider (305) is blocked to prevent the rear end of the light spring (309) from moving out. The mobile receiving mechanism includes a mobile frame (601), a fixed frame (602), a ball screw drive mechanism (604), a slider guide mechanism (605), a support leg (606), and a receiving motor (007). The movable frame (601) is slidably mounted on the fixed frame (602) via the slider guide mechanism (605). The receiving motor (007) is mounted on the fixed frame (602) and is driven to slide left and right on the fixed frame (602) via the ball screw drive mechanism (604). The tensioning mechanism includes a tensioning frame (500), a tensioning motor (501), a large tensioning wheel (502), a small tensioning wheel (503), a side tensioning wheel (504), a dual-shaft cylinder (506), and a tensioning slider (507); The tensioning frame (500) is mounted on the movable frame (601), the tensioning slider (507) is slidably mounted on the tensioning frame (500), the tensioning motor (501) is mounted on the tensioning frame (500), the tensioning motor (501) drives the tensioning slider (507) to slide up and down through the ball screw nut, the large tensioning wheel (502) is fixedly mounted on the tensioning frame (500), and the small tensioning wheel (503) is fixedly mounted on the tensioning slider (507); A dual-axis cylinder (506) is mounted on a movable frame (601), and a side tensioning wheel (504) is provided at its extended rod end to tension the belt from the side. The feeding mechanism includes a retaining ring (401), a feeding lever (402), a feeding shaft (403), a rotating arm (406), a feeding bracket (405), a feeding cylinder (404), and a swing arm (407). The feeding bracket (405) is mounted on the movable frame (601), the feeding shaft (403) is rotatably mounted on the feeding bracket (405), one end of the swing rod (407) is connected to the feeding shaft (403), the other end of the swing rod (407) is connected to the feeding lever (402), the retaining ring (401) is located at the connection between the swing rod (407) and the feeding lever (402), the tail end of the feeding cylinder (404) is rotatably mounted on the movable frame (601), the rod end of the feeding cylinder (404) is rotatably connected to the rotating arm (406), and the other end of the rotating arm (406) is fixedly connected to the feeding shaft (403); The feeding auxiliary cylinder (702) is mounted on the movable frame (601) via a bracket (703), and the rod end of the feeding auxiliary cylinder (702) is connected to the push plate (701).

2. The loading and unloading device of the transmission belt appearance defect detection equipment as described in claim 1, characterized in that, It also includes a first locking ring (103), a second locking ring (104), a first stop (108), a second stop (109), and a locking handle (107). The first locking ring (103) is fixedly installed on the lower support column (102) by bolts and nuts, and the second locking ring (104) is fixedly installed on the upper support column (105) by bolts and nuts. The first stop block (108) is fixedly set on the first locking ring (103), and the second stop block (109) is fixedly set on the second locking ring (104). The front end of the locking handle (107) is a screw rod. After passing through the holes of the first stop block (108) and the second stop block (109), the nut is tightened to fix the two.

3. The loading and unloading device of the transmission belt appearance defect detection equipment as described in claim 1, characterized in that, The feeding mechanism consists of one set on each side, symmetrically positioned on both sides of the large tension wheel.

4. The loading and unloading device of the transmission belt appearance defect detection equipment as described in claim 1, characterized in that, There are also two feeding auxiliary cylinders (702), one on the left and one on the right, located on both sides of the large tensioning wheel.

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