Cable stranding machine
By designing a detachable pay-off and take-up roller structure, the problems of inconvenient replacement and safety hazards of existing cable stranding machines are solved, enabling the stranding and stable winding of cables with different strand numbers, and improving the flexibility and safety of cable processing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBEI HUATONG WIRES & CABLES GRP CO LTD
- Filing Date
- 2025-06-29
- Publication Date
- 2026-06-19
AI Technical Summary
Existing cable stranding machines are inconvenient to replace the pay-off and take-up rollers and pose safety hazards, and cannot meet the stranding requirements of cables with different numbers of strands.
A cable stranding machine was designed, comprising stranding, unwinding, limiting, and winding mechanisms. It adopts a stainless steel base plate structure and is driven by a reducer and a stranding motor. It features a detachable unwinding roller and winding roller structure. The unwinding roller can be easily replaced through a threaded rod and limiting holes, while the winding roller can be safely replaced using a slewing bearing and a synchronous belt drive.
It improves the ease and safety of replacing the wire feeding roller, adapts to the stranding requirements of cables with different strand numbers, and ensures the stability and safety of the stranding process.
Smart Images

Figure CN224383969U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cable processing technology, and in particular to a cable stranding machine. Background Technology
[0002] A cable is an electrical or signal transmission device, typically composed of several or groups of conductors, covered with insulation and protective materials. It is widely used in power systems, information transmission, and other fields, and is indispensable in daily life and industrial production; household appliances and communication network connections all rely on it. Cable processing is the process of transforming raw materials into finished cables. First, materials are selected, choosing high-quality metals such as copper and aluminum as conductors, and suitable insulation materials. Next, the conductors are processed, shaping the metal into the required form. Then, the insulation layer and sheath are processed and coated to ensure the cable's insulation and durability. Finally, testing ensures the cable meets quality standards. The entire processing process requires strict control to produce reliable, high-quality cable products.
[0003] During cable processing, cable manufacturers often use stranding machines to twist multiple single or double strands of wire together, making the wires intertwined and tightly bound to prevent loosening and improve cable flexibility for easier laying. Existing stranding machines are mostly fixed-strand machines, lacking a convenient pay-off roller installation structure. For example, Chinese utility model patent CN222785095U describes a device with four pay-off frames lacking a convenient disassembly mechanism, and the stranding reel only has four threading holes. Therefore, this device is only suitable for stranding four-strand cables, resulting in low flexibility. Furthermore, existing cable stranding devices often lack convenient take-up mechanisms. Some cable stranding devices use a telescopic mechanism to change the distance between the clamping parts on both sides to release the lock on the take-up roller, thus enabling convenient replacement. However, this structure requires an additional telescopic drive mechanism, and when the clamping parts on both sides open, the take-up roller will lose its grip and fall, causing the wound cable to vibrate and loosen, or even roll and cause danger. For example, Chinese utility model patent with announcement number CN222785095U uses a telescopic component to push the first slider to slide, thereby increasing the distance between the two rotating disks and releasing the clamp on the take-up drum. This device requires an additional telescopic component to drive the first slider, and when the clamp on the take-up drum is released from the two rotating disks, the take-up drum will fall downwards.
[0004] Therefore, there is an urgent need to provide a cable stranding machine to solve the above problems. Utility Model Content
[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a cable stranding machine.
[0006] To solve the above-mentioned technical problems, the present invention provides a cable stranding machine, comprising a base plate mechanism and a stranding mechanism. A first drive mechanism is fixed on the base plate mechanism, and a stranding mechanism for stranding multiple strands of cable is fixed on the first drive mechanism. The stranding mechanism includes a stranding shaft connected to the output end of a reducer, a mounting plate is fixed on the stranding shaft, and multiple fixed platforms are arranged in a circular array on the mounting plate. A stranding disc is also fixed at the end of the stranding shaft, and multiple wire-passing holes are arranged in a circular array on the stranding disc. Multiple wire-feeding mechanisms are fixed on the stranding mechanism.
[0007] The wire feeding mechanism is press-fitted with a wire feeding roller;
[0008] The base plate mechanism is also fixed with a limiting mechanism for limiting the cable, a winding mechanism for winding the cable, and a second driving mechanism for driving the winding mechanism.
[0009] Through the above technical solution, the stranding motor can drive the stranding shaft to rotate via a reducer, thereby causing the mounting disc and the stranding disc to rotate synchronously, thus preventing cable tangling. The stranding shaft is fixed to the inner ring of bearing one, allowing the stranding shaft to rotate relative to the support frame and be supported by the support frame, improving the stability of the stranding mechanism. When the stranding disc rotates, it can twist the multiple strands of cable passing through each wire hole into one, thereby forming the cable.
[0010] The present invention is further configured such that: the base plate mechanism includes a plate body, a support frame is fixed on the plate body, a bearing is fixed on the inner side of the support frame, and a fixing frame is integrally fixed on the plate body.
[0011] Through the above technical solution, the plate, support frame and fixing frame are all made of stainless steel, which has good corrosion resistance and high strength. The outer ring of bearing one is fixed to the support frame, and the inner ring of bearing one can rotate relative to the support frame.
[0012] The present invention is further configured such that: the first driving mechanism includes a mounting bracket bolted to the plate, a stranded motor is fixed on the mounting bracket, and a reducer is also fixed on the mounting bracket.
[0013] Through the above technical solution, the output end of the stranded motor is connected to the input end of the reducer. When the stranded motor starts, the reducer can reduce the output speed of the stranded motor and increase its output torque, and output power from the output end.
[0014] The present invention is further configured such that: the wire feeding mechanism includes a bearing two welded to a fixed platform, a rotating disk is fixed to the inner ring of the bearing two, a threaded hole is provided on the rotating disk, the threaded hole is connected to a threaded rod, a pressure plate is provided on the inner side of the free end of the threaded rod, the threaded rod passes through the center hole of the pressure plate, and a screwing block is provided at the end of the threaded rod.
[0015] With the above technical solution, the outer ring of bearing two is fixed to the fixed platform, and the rotating disk can rotate relative to the fixed platform. Before the operator uses the device to strand the wire, they can rotate the screwing block to unscrew the pressure plate and threaded rod from the threaded hole, then pass the threaded rod through the pay-off roller, and screw the threaded rod back into the threaded hole through the screwing block. At this time, the pressure plate and the rotating disk will press the pay-off roller. When the device pays the wire, the rotating disk will rotate, thereby reducing the pay-off resistance. The pressure plate and threaded rod are easy to disassemble and assemble, and the operator can easily replace the pay-off roller. The number of pay-off rollers can also be increased or decreased according to the usage requirements, so that the device can be used for stranding of cables with different numbers of strands.
[0016] The present invention is further configured such that: the limiting mechanism includes a stand fixed on the plate, a bolt is threaded through the stand, a limiting frame is bolted to the top of the stand, a bolt is threaded through the limiting frame, and a limiting hole is provided on the limiting frame.
[0017] With the above technical solution, the upright is fixed to the plate by bolt one, and the limiting frame is fixed to the upright by bolt two. The limiting hole on the limiting frame allows the cable to pass through, thereby limiting the cable. The limiting frame can be replaced with different specifications, thus making it suitable for cables with different strand numbers.
[0018] The present invention is further configured such that: the winding mechanism includes a base frame bolted to the plate body, and a pulley frame is integrally fixed at each of the four corners of the base frame; a support pulley is rotatably connected to the inner side of the pulley frame; a winding roller is rotatably connected to the support pulley; a connecting sleeve is provided at the center of the winding roller; and the connecting sleeve is provided with an internal hexagonal hole.
[0019] With the above technical solution, there are four pulley frames, two in each group, and the two groups of pulley frames are parallel to each other. The two pulley frames in each group are collinear. The limiting baffles at both ends of the take-up roller are disc-shaped, and the distance between the two limiting baffles is equal to the distance between the two groups of pulley frames. When the take-up roller rotates, the support pulley will rotate relative to the take-up roller.
[0020] The present invention is further configured such that: the second driving mechanism includes a winding motor fixed on the plate body, a small pulley is fixed at the output end of the winding motor, a synchronous belt is sleeved on the outside of the small pulley, a large pulley is sleeved on the inner side of one end of the synchronous belt, an internal hexagonal sleeve is provided at the center of the large pulley, the internal hexagonal sleeve is provided with an internal hexagonal groove, a hexagonal pin is slidably connected inside the internal hexagonal groove, a positioning pin is provided radially along the internal hexagonal sleeve and penetrating the internal hexagonal sleeve and the hexagonal pin, a locking pin is provided at the end of the positioning pin, the hexagonal pin penetrates the large pulley, and the front end of the hexagonal pin is inserted into the internal hexagonal hole of the connecting sleeve;
[0021] The large pulley is also equipped with a slewing bearing; the slewing bearing includes an inner ring and an outer ring; the inner ring rotates within the outer ring; the inner ring of the slewing bearing is connected to the large pulley; the outer ring is connected to the fixed frame.
[0022] Through the above technical solution, the outer ring of the slewing bearing is welded and fixed to the fixed frame, and the inner ring of the slewing bearing is fixed to the large pulley, so that the large pulley can rotate relative to the fixed frame. The winding motor can drive the large pulley to rotate at a reduced speed through the small pulley and the synchronous belt. The end of the hexagonal pin is inserted into the connecting sleeve. When the large pulley rotates, the inner hexagonal groove will drive the hexagonal pin to rotate, thereby driving the connecting sleeve and the winding roller to rotate, realizing winding. When the winding roller needs to be replaced, the operator first stops the device, then pulls out the locking pin from the positioning pin, and pulls the positioning pin out from the inner hexagonal groove. At this time, the positioning pin no longer locks the hexagonal pin, and the operator can pull the hexagonal pin out from the inner hexagonal groove of the connecting sleeve, thereby releasing the locking of the hexagonal pin on the winding roller. After the locking is released, the support pulley will support the winding roller, thereby preventing the winding roller from falling. At this time, the operator can replace the winding roller.
[0023] The beneficial effects of this utility model are as follows:
[0024] 1. This utility model effectively improves the convenience of replacing the wire feeding roller by setting up a stranding mechanism, a wire feeding mechanism, a wire feeding roller and a limiting mechanism. Moreover, the staff can increase or decrease the number of wire feeding rollers according to the needs of use, thereby realizing the stranding of cables with different numbers of strands.
[0025] 2. With the addition of a winding mechanism and a second drive mechanism, this invention enables the rapid replacement of the winding roller without the need for additional power extension components, and the winding roller will not fall during replacement, effectively improving the safety of the device. Attached Figure Description
[0026] Figure 1 This is a three-dimensional structural diagram of the present invention;
[0027] Figure 2 This is a structural diagram of the base plate mechanism of this utility model;
[0028] Figure 3 This is a structural diagram of the first drive mechanism and the stranding mechanism of this utility model;
[0029] Figure 4 This is a structural diagram of the wire feeding mechanism and wire feeding roller of this utility model;
[0030] Figure 5 This is a structural diagram of the limiting mechanism of this utility model;
[0031] Figure 6 This is a structural diagram of the winding mechanism of this utility model;
[0032] Figure 7 This is a structural diagram of the second drive mechanism of this utility model.
[0033] In the diagram: 1. Base plate mechanism; 101. Plate body; 102. Support frame; 103. Bearing 1; 104. Fixing frame; 2. First drive mechanism; 201. Mounting frame; 202. Stranded wire motor; 203. Reducer; 3. Stranded wire mechanism; 301. Stranded wire shaft; 302. Mounting plate; 303. Fixing platform; 304. Stranded wire reel; 305. Threading hole; 4. Wire feeding mechanism; 401. Bearing 2; 402. Rotating plate; 403. Threaded hole; 404. Threaded rod; 405. Pressure plate; 406. Twisting block; 5. Wire feeding roller; 6. Limiting Positioning mechanism; 601, upright frame; 602, bolt one; 603, limiting frame; 604, bolt two; 605, limiting hole; 7, winding mechanism; 701, base frame; 702, pulley frame; 703, support pulley; 704, winding roller; 705, connecting sleeve; 8, second drive mechanism; 801, winding motor; 802, small pulley; 803, synchronous belt; 804, large pulley; 805, internal hexagonal groove; 806, hexagonal pin; 807, positioning pin; 808, locking pin; 809, slewing bearing; 810, internal hexagonal sleeve. Detailed Implementation
[0034] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.
[0035] Please see Figures 1-7A cable stranding machine includes a base plate mechanism 1 and a stranding mechanism 3. The base plate mechanism 1 includes a plate 101, a support frame 102 fixed on the plate 101, a bearing 103 fixed on the inner side of the support frame 102, and a fixing frame 104 integrally fixed on the plate 101. The plate 101, support frame 102, and fixing frame 104 are all made of stainless steel, which has good corrosion resistance and high strength. The outer ring of the bearing 103 is fixed to the support frame 102, and the inner ring of the bearing 103 can be connected to the support frame. 102 rotates relative to each other. A first drive mechanism 2 is fixed on the base plate mechanism 1. The first drive mechanism 2 includes a mounting bracket 201 bolted to the plate 101. A stranded motor 202 is fixed on the mounting bracket 201. A reducer 203 is also fixed on the mounting bracket 201. The output end of the stranded motor 202 is connected to the input end of the reducer 203. When the stranded motor 202 starts, the reducer 203 can reduce the output speed of the stranded motor 202 and increase its output torque, and output power from the output end.
[0036] like Figure 1 and Figure 3 As shown, a stranding mechanism 3 for twisting multiple strands of cable is fixed on the first drive mechanism 2. The stranding mechanism 3 includes a stranding shaft 301 connected to the output end of the reducer 203. A mounting plate 302 is fixed on the stranding shaft 301. Multiple fixed platforms 303 are arranged in a ring on the mounting plate 302. A stranding disc 304 is also fixed at the end of the stranding shaft 301. Multiple wire-passing holes 305 are arranged in a ring on the stranding disc 304. The stranding motor 202 can drive the stranding shaft 301 to rotate through the reducer 203, so that the mounting plate 302 and the stranding disc 304 rotate synchronously, thereby avoiding cable tangling. The stranding shaft 301 is fixed to the inner ring of the bearing 103, so that the stranding shaft 301 can rotate relative to the support frame 102 and be supported by the support frame 102, which improves the stability of the stranding mechanism 3. When the stranding disc 304 rotates, it can twist the multiple strands of cable passing through each wire-passing hole 305 into one strand, thereby forming the cable.
[0037] like Figure 1 and Figure 4As shown, multiple wire feeding mechanisms 4 are fixed on the wire stranding mechanism 3. Each wire feeding mechanism 4 includes a bearing 401 welded to a fixed platform 303. A rotating disk 402 is fixed to the inner ring of the bearing 401. The rotating disk 402 has a threaded hole 403 connected to a threaded rod 404. A pressure plate 405 is located inside the free end of the threaded rod 404, and the threaded rod 404 passes through the center hole of the pressure plate 405. A turning block 406 is located at the end of the threaded rod 404. The outer ring of the bearing 401 is fixed to the fixed platform 303. The rotating disk 402 can rotate relative to the fixed platform 303. When the operator uses this device to perform wire stranding... Before the wire is laid, the rotating screw block 406 can be rotated to unscrew the pressure plate 405 and the threaded rod 404 from the threaded hole 403. Then, the threaded rod 404 is passed through the wire feeding roller 5 and screwed back into the threaded hole 403 by the screw block 406. At this time, the pressure plate 405 and the rotating disk 402 will press the wire feeding roller 5. When the device feeds the wire, the rotating disk 402 will rotate, thereby reducing the wire feeding resistance. The pressure plate 405 and the threaded rod 404 are easy to disassemble and assemble, and the operator can easily replace the wire feeding roller 5. The number of wire feeding rollers 5 can also be increased or decreased according to the usage requirements, so that the device can be used for stranding of cables with different numbers of strands.
[0038] like Figure 1 , Figure 5 and Figure 6 As shown, a feeding roller 5 is pressed onto the feeding mechanism 4, and a limiting mechanism 6 for limiting the cable is fixed on the base plate mechanism 1. The limiting mechanism 6 includes a stand 601 fixed on the plate 101, a bolt 602 passing through the stand 601, a limiting frame 603 bolted to the top of the stand 601, a bolt 604 passing through the limiting frame 603, and a limiting hole 605 provided on the limiting frame 603. The stand 601 is fixed to the plate 101 by the bolt 602, and the limiting frame 603 is fixed to the stand 601 by the bolt 604. The limiting hole 605 on the limiting frame 603 allows the cable to pass through, thereby limiting the cable. The limiting frame 603 can be replaced with different specifications, thus being suitable for cables with different strand counts. The base plate mechanism 1 is also fixed with a limiting mechanism 6 for limiting the cable. The cable winding mechanism 7 includes a base frame 701 bolted to the plate 101. Each of the four corners of the base frame 701 is integrally fixed with a pulley frame 702. A support pulley 703 is rotatably connected to the inner side of the pulley frame 702. A winding roller 704 is rolled on the support pulley 703. A connecting sleeve 705 is provided at the center of the winding roller 704. The connecting sleeve 705 is provided with an internal hexagonal hole. There are four pulley frames 702 in total, with two in each group. The two groups of pulley frames 702 are parallel to each other, and the two pulley frames 702 in each group are collinear. The limiting baffles at both ends of the winding roller 704 are disc-shaped, and the distance between the two limiting baffles is equal to the distance between the two groups of pulley frames 702. When the winding roller 704 rotates, the support pulley 703 will rotate relative to the winding roller 704.
[0039] like Figure 1 and Figure 7 As shown, a second drive mechanism 8 for driving the winding mechanism 7 is also fixed on the base plate mechanism 1. The second drive mechanism 8 includes a winding motor 801 fixed on the plate body 101. A small pulley 802 is fixed at the output end of the winding motor 801. A synchronous belt 803 is sleeved on the outside of the small pulley 802. A large pulley 804 is sleeved on the inner side of one end of the synchronous belt 803. An internal hexagonal sleeve 810 is provided at the center of the large pulley 804. An internal hexagonal groove 805 is provided on the internal hexagonal groove 805. A hexagonal pin 806 is slidably connected inside the internal hexagonal groove 805. A positioning pin 807 is provided radially on the internal hexagonal sleeve 810, penetrating the internal hexagonal sleeve 810 and the hexagonal pin 806. A locking pin 808 is provided at the end of the positioning pin 807. The hexagonal pin 806 penetrates the large pulley 804. The front end of the hexagonal pin 806 is inserted into the internal hexagonal hole of the connecting sleeve 705.
[0040] A slewing bearing 809 is also provided on the large pulley 804; the slewing bearing 809 includes an inner ring and an outer ring; the inner ring rotates within the outer ring; the inner ring of the slewing bearing 809 is welded to the large pulley 804; the outer ring is fixedly connected to the fixed frame 104, thereby enabling the large pulley 804 to rotate relative to the fixed frame 104. The winding motor 801 can drive the large pulley 804 to rotate at a reduced speed through the small pulley 802 and the synchronous belt 803. The end of the hexagonal pin 806 is inserted into the connecting sleeve 705. When the large pulley 804 rotates, the inner hexagonal groove 805 will drive the hexagonal pin 806 to rotate, thereby driving the connecting sleeve 705. The take-up roller 704 rotates to achieve winding. When the take-up roller 704 needs to be replaced, the operator first stops the device, then pulls out the locking pin 808 from the positioning pin 807, and pulls the positioning pin 807 out of the internal hexagonal groove 805. At this time, the positioning pin 807 no longer locks the hexagonal pin 806, and the operator can pull the hexagonal pin 806 out of the internal hexagonal groove 805 of the connecting sleeve 705, thereby releasing the locking of the hexagonal pin 806 on the take-up roller 704. After the locking is released, the support pulley 703 will support the take-up roller 704, thereby preventing the take-up roller 704 from falling. At this time, the operator can replace the take-up roller 704.
[0041] When using this utility model, the operator first aligns and installs the corresponding number of wire feeding rollers 5 on the wire feeding mechanism 4 according to actual needs. Then, each wire core is passed through the corresponding wire threading hole 305, and the ends of the wire cores are twisted together, passed through the limiting hole 605, and fixed to the winding roller 704. The device can then be turned on. When the device is started, the first drive mechanism 2 drives the twisting mechanism 3 to rotate and twists the multiple wire cores into one strand. The winding mechanism 7 can then wind up the formed cable.
[0042] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.
Claims
1. A cable stranding machine for stranding a cable comprising a bottom plate mechanism (1) and a stranding mechanism (3), characterized in that: The base plate mechanism (1) is fixed with a first drive mechanism (2), and the first drive mechanism (2) is fixed with a stranding mechanism (3) for stranding multiple cables. The stranding mechanism (3) includes a stranding shaft (301) connected to the output end of the reducer (203). The stranding shaft (301) is fixed with a mounting plate (302). The mounting plate (302) has multiple fixed platforms (303) arranged in a ring. The end of the stranding shaft (301) is also fixed with a stranding disc (304). The stranding disc (304) has multiple wire holes (305) arranged in a ring. The stranding mechanism (3) is fixed with multiple wire feeding mechanisms (4). The wire feeding mechanism (4) is press-fitted with a wire feeding roller (5). The base plate mechanism (1) is also fixed with a limiting mechanism (6) for limiting the cable, a winding mechanism (7) for winding the cable, and a second driving mechanism (8) for driving the winding mechanism (7).
2. A cable stranding machine according to claim 1, characterised in that: The base plate mechanism (1) includes a plate (101), a support frame (102) is fixed on the plate (101), a bearing (103) is fixed on the inner side of the support frame (102), and a fixing frame (104) is also integrally fixed on the plate (101).
3. A cable stranding machine according to claim 2, characterised in that: The first drive mechanism (2) includes a mounting bracket (201) bolted to the plate (101), a stranded motor (202) fixed on the mounting bracket (201), and a reducer (203) fixed on the mounting bracket (201).
4. A cable stranding machine according to claim 3, characterised in that: The wire feeding mechanism (4) includes a bearing two (401) welded to a fixed platform (303). A rotating disk (402) is fixed to the inner ring of the bearing two (401). A threaded hole (403) is provided on the rotating disk (402). The threaded hole (403) is connected to a threaded rod (404). A pressure plate (405) is provided on the inner side of the free end of the threaded rod (404). The threaded rod (404) passes through the center hole of the pressure plate (405). A screwing block (406) is provided at the end of the threaded rod (404).
5. A cable stranding machine according to claim 4, characterised in that: The limiting mechanism (6) includes a stand (601) fixed on the plate (101), a bolt (602) is provided on the stand (601), a limiting frame (603) is bolted to the top of the stand (601), a bolt (604) is provided on the limiting frame (603), and a limiting hole (605) is provided on the limiting frame (603).
6. A cable stranding machine according to claim 5, characterized in that: The winding mechanism (7) includes a base frame (701) bolted to the plate (101). Each of the four corners of the base frame (701) is integrally fixed with a pulley frame (702). A support pulley (703) is rotatably connected to the inner side of the pulley frame (702). A winding roller (704) is rolled on the support pulley (703). A connecting sleeve (705) is provided at the center of the winding roller (704). The connecting sleeve (705) is provided with an internal hexagonal hole.
7. A cable stranding machine according to claim 6, characterized in that: The second drive mechanism (8) includes a take-up motor (801) fixed on the plate (101). A small pulley (802) is fixed at the output end of the take-up motor (801). A timing belt (803) is sleeved on the outside of the small pulley (802). A large pulley (804) is sleeved on the inner side of one end of the timing belt (803). An internal hexagonal sleeve (810) is provided at the center of the large pulley (804). The internal hexagonal sleeve (810) is provided with an internal hexagonal slide. The groove (805) is internally connected to a hexagonal pin (806). The internal hexagonal sleeve (810) is radially provided with a positioning pin (807) that passes through the internal hexagonal sleeve (810) and the hexagonal pin (806). The end of the positioning pin (807) is provided with a locking pin (808). The hexagonal pin (806) passes through the large pulley (804). The front end of the hexagonal pin (806) is inserted into the internal hexagonal hole of the connecting sleeve (705). The large pulley (804) is also provided with a slewing bearing (809); the slewing bearing (809) includes an inner ring and an outer ring; the inner ring rotates within the outer ring; the inner ring of the slewing bearing (809) is connected to the large pulley (804); the outer ring is connected to the fixed frame (104).