Transfer equipment for wafer production

Abstract

The invention relates to the technical field of wafer production, in particular to transfer equipment for wafer production, which comprises a base and a transfer mechanism, the transfer mechanism comprises two side plates and two outer guide rails, a limiting mechanism is arranged between the two outer guide rails, and the limiting mechanism comprises four sliding assemblies and a limiting clamping plate. The sliding assembly comprises two sliding blocks of a circular structure, two connecting rods and a movable block, the two sliding blocks are slidably connected between the outer guide rail and the side plate, one side of each sliding block is fixedly connected with the chain, the connecting rods correspond to the sliding blocks one to one, the connecting rods are fixedly connected to one sides of the sliding blocks, and the movable block is fixedly connected with the connecting rods. The four limiting clamping plates are fixedly installed on the four movable blocks in the same limiting mechanism correspondingly. According to the wafer cleaning device, the chain is driven to rotate through the driving motor, then the limiting clamping plate in the limiting mechanism drives the wafer to move through the sliding block, and the position accuracy of the wafer during cleaning is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer production, and in particular to a transfer device for wafer production. Background Art

[0002] A wafer is a semiconductor chip made from a silicon crystal rod. It is a single round piece formed through processes such as grinding, polishing and slicing. During the wafer production process, transfer equipment is required to carry the wafer to move.

[0003] Among them, when the wafer is not only processed and polished, the surface of the wafer will be contaminated due to contact with organic matter, particles, etc., therefore, it is necessary to clean the wafer after the above-mentioned processing technology, especially during cleaning, it is also necessary to use transfer equipment to transport the wafer. In the prior art, a conveyor belt is usually used to transport the wafer, which can easily cause the wafer to vibrate during the transfer process, resulting in deviation of its transportation trajectory. When entering the cleaning mechanism, a clamping roller is usually set on the wafer movement trajectory, and the wafer is driven to move by the clamping rollers on the upper and lower parts of the wafer, and the upper and lower spiral rotating cleaning rollers contact the upper and lower surfaces of the wafer respectively, and the opposite forces generated by the two cleaning rollers offset each other to achieve the centering of the wafer, and the cleaning of the wafer is completed at the same time. However, after the cleaning roller has been in operation for a long time, due to continuous contact with the surface of the wafer, the roller wall may become thinner due to the friction, resulting in different torques generated by the upper and lower cleaning rollers on the wafer, which may cause the movement trajectory of the wafer to be offset after the cleaning is completed, and the position is not accurate enough. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the background technology and to propose a transfer device for wafer production.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a transfer device for wafer production, comprising a base and a transfer mechanism, the transfer mechanism comprising a side plate and an outer guide rail, the side plate is fixedly mounted on the base, the outer guide rail is welded to the outer side of the side plate by an L-shaped welding frame, two side plates and two outer guide rails are provided, a chain is provided on the side of the two side plates away from each other, any chain is connected by two gears, the gears are rotatably connected to the side plate, a driving motor is fixedly mounted on the top of the base, and the chain and the gear are driven by the driving motor;

[0006] A limiting mechanism is arranged between the two outer guide rails, and the limiting mechanism includes four sliding components and limiting clamps. The sliding component includes a slider, a connecting rod and a movable block of a circular structure. Two sliders and two connecting rods are provided. Both sliders are slidably connected between the outer guide rail and the side plate. One side of the slider is fixedly connected to the chain. The connecting rod corresponds to the slider one by one. The connecting rod is fixedly connected to one side of the slider. The movable block is fixedly connected to the connecting rod. Four limiting clamps are provided and are respectively fixedly mounted on the four movable blocks in the same limiting mechanism.

[0007] In the above-mentioned transfer equipment for wafer production, any of the limiting clamps is provided with a clamping surface with an arc-shaped structure, the thickness of the limiting clamp is smaller than the thickness of the wafer, and the wafer body is clamped between the four limiting clamps.

[0008] In the above-mentioned transfer equipment for wafer production, two stabilizing mechanisms are arranged on the movable block, and the two stabilizing mechanisms are respectively arranged at the upper and lower parts of the movable block, and the two stabilizing mechanisms are symmetrically distributed. The stabilizing mechanisms include a notch, a rotating groove, an axle rod, a connecting groove and a stabilizing splint. The notch is opened in the middle of the movable block. There are two rotating grooves in any stabilizing mechanism, and the two rotating grooves are respectively opened on the two side walls of the same notch. There are two connecting grooves, and the two connecting grooves are respectively opened on both sides of the notch. The two connecting grooves are respectively connected to the two rotating grooves, and the two ends of the axle rod respectively pass through the two rotating grooves and are inserted into the two connecting grooves. The stabilizing splint is welded to the two ends of the axle rod.

[0009] In the above-mentioned transfer equipment for wafer production, a tooth plate is slidably connected to the notch in any of the stabilizing mechanisms, a half-tooth shaft is fixedly arranged on any of the shaft rods, a driving block is fixedly installed on the side of the tooth plate close to the outer guide rail, a triangular-structured inclined surface is provided on the driving block, an extrusion bar 1 is fixedly installed on the side where the two outer guide rails are close to each other, and two symmetrical extrusion bars 2 are fixedly installed on the side where the two outer guide rails are close to each other.

[0010] In the above-mentioned transfer equipment for wafer production, a limiting mechanism compatible with the stabilizing mechanism is arranged on any of the movable blocks, and the limiting mechanism includes a guide plate, a roller, a transmission belt and a limiting rod. The guide plate is fixedly mounted on the side of the tooth plate away from the driving block, and the roller is rotatably connected to the upper surface of the stabilizing clamp. A sliding rod is fixedly mounted on the plate surface of the limiting clamp, and the limiting rod is slidably arranged on the sliding rod. A yield groove is provided on the stabilizing clamp.

[0011] In the above-mentioned transfer equipment for wafer production, a buffer mechanism compatible with the stabilizing mechanism is arranged on any of the stabilizing clamps, and the buffer mechanism includes two mounting seats and a buffer airbag. The two mounting seats are fixedly mounted on the plate surface of the stabilizing clamp by bolts, and the buffer airbag is fixedly arranged between the two mounting seats.

[0012] In the above-mentioned transfer equipment for wafer production, a support plate with an arc-shaped structure corresponding to the buffer airbag is fixedly mounted on the stabilizing clamping plate, and the support plate is in contact with the buffer airbag.

[0013] In the above-mentioned transfer device for wafer production, the opening direction of the inclined surface on any of the driving blocks is consistent with the movement direction, and the rotation direction of the driving motor driving the chain is adapted to the force direction of the inclined surface.

[0014] Compared with the prior art, the advantages of the present invention are:

[0015] 1. The chain is driven by a driving motor to rotate, and then the limiting clamp in the limiting mechanism is used to drive the wafer to move through the slider, thereby improving the accuracy of the wafer position during cleaning. The upper surface of the wafer is clamped by the stabilizing clamp on the upper part of the wafer, and the lower surface of the wafer is supported by the stabilizing clamp on the lower part of the wafer, thereby improving the stability of the transfer and avoiding wafer deviation.

[0016] 2. By squeezing the bar, the two drive blocks on the same side are simultaneously pressed against each other, and the corresponding drive blocks are driven to move under the action of the inclined surface, thereby causing the tooth plate to move away from the drive block. When the tooth plate moves a specified distance, the tooth plate engages with the half-tooth shaft, thereby driving the shaft rod to rotate, and the shaft rod drives the stabilizing plate on the upper part of the limit clamp to rotate, which is convenient for wafer placement.

[0017] 3. The driving block is squeezed by the squeezing bar 2, so that the two stabilizing clamps in the front stabilizing mechanism are rotated, and the rear stabilizing clamp keeps supporting and clamping the wafer, so that the wafer can accurately enter the cleaning mechanism for cleaning. When the wafer moves a specified distance, the rear driving block contacts the squeezing bar 2, thereby releasing the stabilizing clamp in the rear stabilizing mechanism, allowing the wafer to enter the cleaning mechanism as a whole. The wafer is limited by the limiting clamp to avoid position displacement of the wafer during the cleaning process, thereby improving the stability of wafer transfer and the accuracy of position during cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0019] Figure 2 The present invention Figure 1 Schematic diagram of the local enlarged structure at point A in the middle.

[0020] Figure 3 The present invention Figure 1 Schematic diagram of the local enlarged structure at point B in the middle.

[0021] Figure 4 It is a partial three-dimensional structural schematic diagram of the limiting mechanism of the present invention.

[0022] Figure 5 It is a partial three-dimensional structural schematic diagram of the stabilizing splint of the present invention.

[0023] Figure 6 It is a partial three-dimensional structural schematic diagram of the limiting clamping plate and the clamping surface of the present invention.

[0024] Figure 7 It is a schematic diagram of the planar structure of the limiting mechanism of the present invention.

[0025] Figure 8 It is a partial cross-sectional structural schematic diagram of the notch of the present invention.

[0026] In the figure: 1. base; 11. side plate; 12. outer guide rail; 13. chain; 14. gear; 15. drive motor; 2. slider; 21. connecting rod; 22. movable block; 221. notch; 222. rotating groove; 223. shaft; 224. connecting groove; 225. stabilizing clamp; 226. tooth plate; 227. half tooth shaft; 228. give way groove; 23. limiting clamp; 231. clamping surface; 232. wafer body; 3. driving block; 31. inclined surface; 16. extrusion strip one; 17. extrusion strip two; 41. guide plate; 42. roller; 43. transmission belt; 44. limiting rod; 45. slide bar; 61. mounting seat; 62. cushioning airbag; 63. support plate. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0028] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] Reference Figure 1-Figure 8A transfer device for wafer production includes a base 1 and a transfer mechanism, the transfer mechanism includes a side plate 11 and an outer guide rail 12, the side plate 11 is fixedly mounted on the base 1, the outer guide rail 12 is welded to the outer side of the side plate 11 through an L-shaped welding frame, two side plates 11 and two outer guide rails 12 are provided, and a chain 13 is provided on the side of the two side plates 11 away from each other, any chain 13 is connected by two gears 14, and the gear 14 is rotatably connected to the side plate 11, a driving motor 15 is fixedly mounted on the top of the base 1, the chain 13 and the gear 14 are driven by the driving motor 15, a limiting mechanism is provided between the two outer guide rails 12, the limiting mechanism includes four sliding components and a limiting clamping plate 23, the sliding The moving component includes a slider 2, a connecting rod 21 and a movable block 22 of a circular structure. Two sliders 2 and two connecting rods 21 are provided. The two sliders 2 are slidably connected between the outer guide rail 12 and the side plate 11. One side of the slider 2 is fixedly connected to the chain 13. The connecting rod 21 corresponds to the slider 2 one by one. The connecting rod 21 is fixedly connected to one side of the slider 2. The movable block 22 is fixedly connected to the connecting rod 21. Four limiting clamps 23 are provided and are respectively fixedly installed on four movable blocks 22 in the same limiting mechanism. The chain 13 is driven to rotate by the driving motor 15, and then the limiting clamps 23 in the limiting mechanism drive the wafer to move through the slider 2, thereby improving the accuracy of the position of the wafer during cleaning.

[0030] Any limiting clamp 23 is provided with a clamping surface 231 with an arc-shaped structure. The thickness of the limiting clamp 23 is less than the thickness of the wafer. A wafer body 232 is clamped between the four limiting clamps 23. The four limiting clamps 23 are convenient for stably clamping the wafer body 232. At the same time, when the wafer body 232 is cleaned, the front and back sides of the wafer body 232 are avoided from being blocked.

[0031] The movable block 22 is provided with two stabilizing mechanisms, which are respectively arranged at the upper part and the lower part of the movable block 22, and are symmetrically distributed. The stabilizing mechanisms include a notch 221, a rotation groove 222, a shaft 223, a connecting groove 224 and a stabilizing splint 225. The notch 221 is provided in the middle of the movable block 22. Two rotating grooves 222 are provided in any stabilizing mechanism, and the two rotating grooves 222 are respectively provided on the two side walls of the same notch 221. Two connecting grooves 224 are provided, and the two connecting grooves 224 are respectively provided on both sides of the notch 221. The connecting groove 224 is respectively connected to the two rotating grooves 222, and the two ends of the shaft rod 223 respectively pass through the two rotating grooves 222 and are inserted into the two connecting grooves 224. The stabilizing clamp 225 is welded to the two ends of the shaft rod 223. The stabilizing clamp 225 is used to clamp the upper and lower surfaces of the wafer body 232 to further increase the stability of the transfer of the wafer body 232 and prevent the wafer body 232 from shaking. The shaft rod 223 is used to drive the stabilizing clamp 225 to rotate. When the wafer body 232 is cleaned, the stabilizing clamp 225 is turned over by the shaft rod 223 to separate it from the wafer body 232.

[0032] A toothed plate 226 is slidably connected to the notch 221 in any stabilizing mechanism, a half-toothed shaft 227 is fixedly arranged on any shaft rod 223, a driving block 3 is fixedly installed on the side of the toothed plate 226 close to the outer guide rail 12, a triangular inclined surface 31 is provided on the driving block 3, an extrusion strip 16 is fixedly installed on the side where the two outer guide rails 12 are close to each other, and two symmetrical extrusion strips 2 17 are fixedly installed on the side where the two outer guide rails 12 are close to each other. When the two driving blocks 3 on the same side simultaneously contact the extrusion strip 16, the corresponding driving blocks 3 are driven to move under the action of the inclined surface 31, and then the toothed plate 226 moves in the direction away from the driving block 3. When the toothed plate 226 moves a specified distance, the toothed plate 226 meshes with the half-toothed shaft 227, and the number of teeth on the toothed plate 226 matches the number of teeth on the half-toothed shaft 227, so that the toothed plate 22 6 can drive the half gear shaft 227 to rotate ninety degrees, thereby driving the shaft rod 223 to rotate, and the shaft rod 223 drives the stabilizing clamping plate 225 on the upper part of the limiting clamping plate 23 to rotate, so as to facilitate the insertion of the wafer body 232. When the driving block 3 passes through the extrusion bar 17, similarly, the two stabilizing clamping plates 225 in the front stabilizing mechanism are rotated, and the rear stabilizing clamping plate 225 maintains support and clamping for the wafer body 232, so as to facilitate the wafer body 232 to accurately enter the cleaning mechanism for cleaning. After the wafer body 232 moves a specified distance, the rear driving block 3 contacts the extrusion bar 17, thereby releasing the stabilizing clamping plate 225 in the rear stabilizing mechanism, so that the wafer body 232 enters the cleaning mechanism as a whole. At this time, the wafer body 232 is limited by the limiting clamping plate 23 to prevent the wafer body 232 from shifting in position during the cleaning process.

[0033] Any movable block 22 is provided with a limiting mechanism adapted to the stabilizing mechanism, the limiting mechanism comprising a guide plate 41, a roller 42, a transmission belt 43 and a limiting rod 44, the guide plate 41 is fixedly mounted on the side of the toothed plate 226 away from the driving block 3, the roller 42 is rotatably connected to the upper surface of the stabilizing splint 225, a slide bar 45 is fixedly mounted on the plate surface of the limiting splint 23, the limiting rod 44 is slidably arranged on the slide bar 45, a yielding groove 228 is provided on the stabilizing splint 225, a spring is sleeved on the slide bar 45 for resetting the limiting rod 44, and the limiting The rod 44 is used to limit the stabilizing plate 225 to prevent the stabilizing plate 225 from shaking during the movement. At the same time, it prevents the stabilizing plate 225 that is against the bottom of the wafer body 232 from falling off under the action of gravity. The tooth plate 226 moves to pull the transmission belt 43, and the limiting rod 44 is pulled out under the action of the roller 42, so that it is separated from the stabilizing plate 225, so that the tooth plate 226 can subsequently drive the stabilizing plate 225 to rotate. When the drive block 3 is separated from the extrusion bar 16 or the extrusion bar 2 17, the stabilizing plate 225 is reset by the spring.

[0034] A buffer mechanism compatible with the stabilizing mechanism is provided on any stabilizing clamp 225, and the buffer mechanism includes two mounting seats 61 and a buffer airbag 62. The two mounting seats 61 are fixed on the plate surface of the stabilizing clamp 225 by bolts, and the buffer airbag 62 is fixed between the two mounting seats 61. When the stabilizing clamp 225 on the upper part of the wafer body 232 clamps the wafer body 232, the relative buffer airbags 62 collide with each other, thereby preventing the stabilizing clamp 225 from directly colliding with the upper surface of the wafer body 232 and causing damage to the wafer body 232.

[0035] A support plate 63 with an arc-shaped structure corresponding to the buffer airbag 62 is fixedly mounted on the stabilizing splint 225 . The support plate 63 contacts the buffer airbag 62 and is used to support the buffer airbag 62 to improve the buffering effect caused by the collision between the buffer airbags 62 .

[0036] The opening direction of the inclined surface 31 on any driving block 3 is consistent with the movement direction. The driving motor 15 drives the chain 13 to rotate in a direction that is consistent with the force direction of the inclined surface 31, thereby preventing the chain 13 from rotating in the opposite direction and causing the extrusion bar 16 to jam the driving block 3.

[0037] The specific working principle and method of use of the present invention are explained in detail below: when in use, the chain 13 is driven to rotate by the driving motor 15, and then the limiting clamping plate 23 in the limiting mechanism drives the wafer body 232 to move through the slider 2. When the two driving blocks 3 on the same side simultaneously abut against the extrusion bar 16, the corresponding driving block 3 is driven to move under the action of the inclined surface 31, and then the tooth plate 226 moves in the direction away from the driving block 3. After the tooth plate 226 moves a specified distance, the tooth plate 226 meshes with the half-tooth shaft 227, thereby driving the shaft rod 223 to rotate, and the stabilizing clamping plate 225 on the upper part of the limiting clamping plate 23 is driven by the shaft rod 223 to rotate ninety degrees, so that it is in a vertical state, which is convenient for the wafer body 232 to be placed in. When the driving block 3 passes through the extrusion bar 2 17, similarly, the four stabilizing clamps 225 in the front stabilizing mechanism are all rotated, and the rear stabilizing clamp 225 maintains support and clamping on the wafer body 232, so that the front of the wafer body 232 can enter the cleaning mechanism for cleaning. When the wafer body 232 moves a specified distance, the rear driving block 3 contacts the extrusion bar 17, thereby releasing the stabilizing clamp 225 in the rear stabilizing mechanism, so that the wafer body 232 enters the cleaning mechanism as a whole. At this time, the wafer body 232 is limited by the limiting clamp 23 to avoid position displacement of the wafer body 232 during the cleaning process, thereby improving the stability of the transfer of the wafer body 232 and the accuracy of the position during cleaning. It should be noted that the front and rear parts use the moving direction of the limiting mechanism as a reference.

[0038] It is further explained that the above-mentioned fixed connection should be understood in a broad sense unless otherwise clearly specified and limited. For example, it can be welding, gluing, or one-piece molding, etc., which are conventional means well known to those skilled in the art.

[0039] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A transfer device for wafer production, comprising a base (1) and a transfer mechanism, characterized in that: The transfer mechanism comprises a side plate (11) and an outer guide rail (12), the side plate (11) is fixedly mounted on the base (1), the outer guide rail (12) is welded to the outer side of the side plate (11) by an L-shaped welding frame, two side plates (11) and two outer guide rails (12) are provided, a chain (13) is provided on the side of the two side plates (11) away from each other, any chain (13) is connected by two gears (14), the gears (14) are rotatably connected to the side plate (11), a driving motor (15) is fixedly mounted on the top of the base (1), and the chain (13) and the gear (14) are driven by the driving motor (15); A limiting mechanism is arranged between the two outer guide rails (12), the limiting mechanism comprising four sliding components and a limiting clamping plate (23), the sliding component comprising a slider (2) of a circular structure, a connecting rod (21) and a movable block (22), two sliders (2) and two connecting rods (21) are provided, both sliders (2) are slidably connected between the outer guide rail (12) and the side plate (11), one side of the slider (2) is fixedly connected to the chain (13), the connecting rod (21) corresponds to the slider (2) one by one, the connecting rod (21) is fixedly connected to one side of the slider (2), the movable block (22) is fixedly connected to the connecting rod (21), and four limiting clamping plates (23) are provided and are respectively fixedly mounted on four movable blocks (22) in the same limiting mechanism.

2. The wafer production transfer device according to claim 1, characterized in that: Any of the limiting clamping plates (23) is provided with a clamping surface (231) with an arc-shaped structure, the thickness of the limiting clamping plate (23) is smaller than the thickness of the wafer, and a wafer body (232) is clamped between the four limiting clamping plates (23).

3. The wafer production transfer device according to claim 2, characterized in that: The movable block (22) is provided with two stabilizing mechanisms, which are respectively arranged at the upper part and the lower part of the movable block (22). The two stabilizing mechanisms are symmetrically distributed. The stabilizing mechanisms include a notch (221), a rotation groove (222), an axle rod (223), a connection groove (224) and a stabilizing clamping plate (225). The notch (221) is provided in the middle part of the movable block (22). Two rotation grooves (222) are provided in any stabilizing mechanism. The two rotation grooves (222) are respectively provided on two side walls of the same notch (221). Two connection grooves (224) are provided. The two connection grooves (224) are respectively provided on both sides of the notch (221). The two connection grooves (224) are respectively connected to the two rotation grooves (222). The two ends of the axle rod (223) respectively penetrate the two rotation grooves (222) and are inserted into the two connection grooves (224). The stabilizing clamping plate (225) is welded to the two ends of the axle rod (223).

4. The wafer production transfer device according to claim 3, characterized in that: A toothed plate (226) is slidably connected to the notch (221) in any of the stabilizing mechanisms, a half toothed shaft (227) is fixedly arranged on any of the shaft rods (223), a driving block (3) is fixedly installed on the side of the toothed plate (226) close to the outer guide rail (12), a triangular inclined surface (31) is provided on the driving block (3), an extrusion strip 1 (16) is fixedly installed on the side of the two outer guide rails (12) close to each other, and two symmetrical extrusion strips 2 (17) are fixedly installed on the side of the two outer guide rails (12) close to each other.

5. The wafer production transfer device according to claim 4, characterized in that: Any of the movable blocks (22) is provided with a limiting mechanism adapted to the stabilizing mechanism, the limiting mechanism comprising a guide plate (41), a roller (42), a transmission belt (43) and a limiting rod (44), the guide plate (41) being fixedly mounted on a side of the tooth plate (226) away from the driving block (3), the roller (42) being rotatably connected to the upper surface of the stabilizing splint (225), a sliding rod (45) being fixedly mounted on the plate surface of the limiting splint (23), the limiting rod (44) being slidably mounted on the sliding rod (45), and a clearance groove (228) being provided on the stabilizing splint (225).

6. The wafer production transfer device according to claim 3, characterized in that: Any of the stabilizing splints (225) is provided with a buffer mechanism that is compatible with the stabilizing mechanism, the buffer mechanism comprising two mounting seats (61) and a buffer airbag (62), the two mounting seats (61) are fixedly mounted on the plate surface of the stabilizing splint (225) by means of bolts, and the buffer airbag (62) is fixedly arranged between the two mounting seats (61).

7. The wafer production transfer device according to claim 6, characterized in that: A support plate (63) having an arc-shaped structure corresponding to the buffer airbag (62) is fixedly mounted on the stabilizing clamping plate (225), and the support plate (63) is in contact with the buffer airbag (62).

8. The wafer production transfer device according to claim 4, characterized in that: The opening direction of the inclined surface (31) on any of the driving blocks (3) is consistent with the movement direction, and the rotation direction of the chain (13) driven by the driving motor (15) is adapted to the force direction of the inclined surface (31).

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