Pulley assembly
By designing a universal pulley assembly, the problem of needing to replace parts for folding cabinet door pulley assemblies was solved, thus improving the versatility and production efficiency of the pulley assembly.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-01
- Publication Date
- 2026-03-31
AI Technical Summary
The existing folding cabinet door pulley assembly requires different components depending on whether it opens to the left or right, which complicates production and increases costs.
Design a pulley assembly in which all components are general-purpose components, and achieve the functions of at least two pulley assemblies by adjusting the direction or installation position of the components, including a top pulley assembly and a bottom pulley assembly.
This achieves the universality of pulley components, reduces production complexity and cost, and improves production efficiency.
Smart Images
Figure CN224064164U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of furniture and household products technology, and in particular to a pulley assembly applied to folding cabinet doors. Background Technology
[0002] As living standards improve, people demand higher quality home life and pay more attention to the space utilization and ease of use of furniture. The emergence of folding cabinet doors has solved the problem of traditional hinged doors requiring a large space to open. During opening and closing, the doors not only move along the track but also rotate, allowing them to fold together and creating a larger open space. Each door has a pulley assembly that works with the track, connected to the door via hinges, with adjacent doors hinged together. When opening and closing, the pulley assembly slides along the track, and the door rotates relative to the pulley assembly due to the hinges, allowing the doors to fold together. However, during installation, folding cabinet doors can open to the left or right, requiring changes in the hinge's position relative to the door and its opening / closing orientation. Therefore, different pulley assemblies with varying structures are needed at different locations on the door, resulting in a diverse range of pulley assemblies achieved through the combination of multiple sets of different structural components. This complicates manufacturing and increases production costs.
[0003] Therefore, it is hoped that a new pulley assembly can be proposed to overcome the above-mentioned defects. Utility Model Content
[0004] The purpose of this utility model is to provide a pulley assembly in which all components are universal components, so as to realize the functions of at least two pulley assemblies.
[0005] To achieve the above objectives, the present invention adopts the following technical solution: a pulley assembly for connecting a door frame and a sliding door, the pulley assembly including a pulley box, a movable wheel assembly that moves vertically relative to the pulley box, and an elastic component connecting the pulley box and the movable wheel assembly. The pulley box has a box body extending vertically, a through groove extending vertically through the box body, and two transverse grooves located inside the box body. The elastic component includes a connector connected to the movable wheel assembly, a screw rod housed in the through groove, a spring sleeved on the screw rod, and a washer held in the transverse groove. One vertical end of the screw rod is connected to the connector and a nut is provided at the other vertical end. All components of the pulley assembly are general-purpose components, and the pulley assembly has at least two forms: a top pulley assembly and a bottom pulley assembly. When the pulley assembly is in the top pulley assembly form, the movable wheel group is located above the pulley box, the connecting member is connected to the lower part of the movable wheel group, the washer is held in the transverse groove adjacent to the movable wheel group, and the upper end of the spring is connected to the washer and the lower end is connected to the nut of the screw. When the pulley assembly is in the bottom pulley assembly form, the movable wheel group is located below the pulley box, the connecting member is connected to the upper part of the movable wheel group, the washer is held in the transverse groove away from the movable wheel group, and the upper end of the spring is connected to the washer and the lower end is connected to the connecting member.
[0006] In a preferred embodiment, the connector has a protrusion that extends partially into the through groove. The protrusion is connected to a vertical end of the screw away from the nut. One end of the spring is connected to the washer and the other end is connected to the nut or the protrusion.
[0007] In a preferred embodiment, when the pulley assembly is in the top pulley assembly form, the protrusion extends downward into the through groove, the screw is assembled vertically from bottom to top into the through groove and passes through the spring and the washer in sequence until it is connected to the protrusion, the washer is disposed adjacent to the protrusion, the upper end of the spring is connected to the washer and the lower end is connected to the nut of the screw.
[0008] In a preferred embodiment, when the pulley assembly is in the bottom pulley assembly form, the protrusion extends upward into the through groove, the screw is assembled vertically from top to bottom into the through groove and passes through the washer and the spring in sequence until it is connected to the protrusion, the washer is disposed adjacent to the nut, the upper end of the spring is connected to the washer and the lower end is connected to the protrusion of the connector.
[0009] In a preferred embodiment, the pulley box has a first short side and a second short side that are parallel to each other, and a first long side and a second long side that are connected to the two sides of the first short side and the second short side laterally. The through groove extends vertically through the first short side and the second short side, and the through groove is disposed adjacent to the first long side. The two transverse grooves include a first transverse groove adjacent to the first short side and a second transverse groove adjacent to the second short side.
[0010] In a preferred embodiment, the pulley box is arranged symmetrically in the vertical direction, and the pulley box has a forward position and a reverse position. When the pulley box is in the forward position, the first short side is above the second short side. When the pulley box is in the reverse position, the second short side is above the first short side.
[0011] In a preferred embodiment, the top pulley assembly is further divided into a forward top pulley assembly and a reverse top pulley assembly; in the forward top pulley assembly, the pulley box is located in the forward position, the screw is inserted into the through groove from the second short side, and the gasket is held in the first transverse groove; in the reverse top pulley assembly, the pulley box is located in the reverse position, the screw is inserted into the through groove from the first short side, and the gasket is held in the second transverse groove.
[0012] In a preferred embodiment, the bottom pulley assembly is further divided into a forward bottom pulley assembly and a reverse bottom pulley assembly; in the forward bottom pulley assembly, the pulley box is located in the forward position, the screw is inserted into the through groove from the first short side and the gasket is held in the first transverse groove; in the reverse bottom pulley assembly, the pulley box is located in the reverse position, the screw is inserted into the through groove from the second short side and the gasket is held in the second transverse groove.
[0013] In a preferred embodiment, the connector is L-shaped and has a connecting seat extending laterally and a protrusion extending vertically from the connecting seat. The protrusion extends into the through groove. The movable wheel assembly has a seat and several movable wheels mounted on the seat. The seat has a mounting portion extending laterally beyond the first long side and a retaining portion extending vertically from the mounting portion. The movable wheels are fixed to the mounting portion, and the retaining portion is laterally assembled to the connecting seat of the connector.
[0014] In a preferred embodiment, the connector is provided with a slot extending laterally, and the seat body is provided with retaining protrusions protruding outward from both longitudinal sides of the retaining portion. The retaining portion of the seat body is inserted into the connector from one side of the second long side laterally toward one side of the first long side. At this time, the retaining protrusions are received in the slot, and the retaining portion and the connector are fixed together by means of screw connection.
[0015] Compared with the prior art, the present invention has the following advantages: All components of the pulley assembly are universal parts, and the pulley assembly has at least two forms: a top pulley assembly and a bottom pulley assembly. When the pulley assembly is in the top pulley assembly form, the movable wheel group is located above the pulley box, the connecting member is connected to the lower part of the movable wheel group, the washer is held in the transverse groove adjacent to the movable wheel group, and the upper end of the spring is connected to the washer and the lower end is connected to the nut of the screw. When the pulley assembly is in the bottom pulley assembly form, the movable wheel group is located below the pulley box, the connecting member is connected to the upper part of the movable wheel group, the washer is held in the transverse groove away from the movable wheel group, and the upper end of the spring is connected to the washer and the lower end is connected to the connecting member. All components of the pulley assembly are universal parts, and the functions of at least two pulley assemblies can be achieved by adjusting the direction or installation position of each component. Attached Figure Description
[0016] Figure 1 This is a three-dimensional schematic diagram of the cabinet door device in a preferred embodiment of the present invention.
[0017] Figure 2 yes Figure 1 The front view of the cabinet door assembly shown.
[0018] Figure 3 yes Figure 2 The cross-sectional view of the top pulley assembly shown.
[0019] Figure 4 yes Figure 3 An exploded view of the forward-facing top pulley assembly is shown.
[0020] Figure 5 yes Figure 2 A cross-sectional view of the reverse top pulley assembly shown.
[0021] Figure 6 yes Figure 5 An exploded view of the reverse top pulley assembly shown.
[0022] Figure 7 yes Figure 2 The cross-sectional view of the bottom pulley assembly shown.
[0023] Figure 8 yes Figure 7 An exploded view of the forward bottom pulley assembly is shown.
[0024] Figure 9 yes Figure 2 The cross-sectional view of the reverse bottom pulley assembly shown.
[0025] Figure 10 yes Figure 9 An exploded view of the reverse bottom pulley assembly shown. Detailed Implementation
[0026] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.
[0027] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model 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, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.
[0028] In the description of this utility model, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating the connection relationship between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0029] Please see Figures 1 to 10 As shown, a preferred embodiment of the present invention discloses a cabinet door device 100, which is typically used in wardrobes in home furnishing products. The wardrobe has a cabinet body and the cabinet door device 100. The cabinet body is used to store clothes or other items, and the cabinet door device 100 is used to close or open the cabinet body.
[0030] Please see Figures 1 to 2 As shown, the cabinet door device 100 includes a door frame 10, at least one movable door 20 located within the door frame 10, and several pulley assemblies 30 connected between the door frame 10 and the movable door 20. The several pulley assemblies 30 are all composed of common parts, so that the pulley assemblies 30 have a wider range of applications.
[0031] The door frame 10 includes a horizontally extending upper door frame 11, a left door frame 12 and a right door frame 13 connected to the horizontal sides of the upper door frame 11, and a horizontally extending and parallel top track 14 and a bottom track 15. The upper door frame 11 is located above the ground and parallel to the ground. The left door frame 12 and the right door frame 13 are parallel to each other and extend vertically to the ground along the horizontal sides of the upper door frame 11. The top track 14 is connected to the bottom of the upper door frame 11. In this embodiment, the door frame 10 does not have a lower door frame, so the bottom track 15 is installed on the ground to reduce the height of the bottom track 15. In other embodiments, the door frame 10 may also have a lower door frame located on the ground, in which case the bottom track 15 is installed on the top of the lower door frame.
[0032] The movable door 20 is located between the top track 14 and the bottom track 15. In this embodiment, the top track 14 and the bottom track 15 limit and guide the movement of the movable door 20. The movable door 20 is a movable folding door that is movable on the door frame 10 and can be folded. Specifically, the movable door 20 is provided with a pair of door leaves 21 and a hinge 22 connected between the pair of door leaves 21. The pair of door leaves 21 can be folded relative to the hinge 22. In other embodiments, two adjacent door leaves 21 can also be connected by a pivot, hinge, etc.
[0033] Combination Figure 1 As shown, the sliding door 20 can be moved to any position as needed to ensure that the interior space of the cabinet can be opened, thus facilitating the storage and retrieval of items inside the cabinet and the opening of side drawers, improving the utilization rate and ease of use of the furniture. In this embodiment, there are two sliding doors 20, arranged side by side in a horizontal direction, and each sliding door 20 has two door leaves 21. In other embodiments, the sliding door 20 may have three, four, or other numbers of door leaves 21 as needed, and the pulley assembly 30 on each sliding door 20 is not limited to two sets, but may also have multiple sets.
[0034] Please see Figures 3 to 10 As shown, the pulley assembly 30 is connected to the sliding door 20 to enable the sliding door 20 to slide on the door frame 10. In this embodiment, several pulley assemblies 30 are respectively disposed on the door leaf 21 of the sliding door 20 at the corner away from the hinge 22. Each pulley assembly 30 is provided with a pulley box 40 fixed to the sliding door 20, a moving wheel group 50 that moves vertically relative to the pulley box 40, and an elastic member 60 connecting the pulley box 40 and the moving wheel group 50. In this embodiment, the moving wheel group 50 is lifted or pushed against the pulley box 40 by the elastic member 60.
[0035] The plurality of pulley assemblies 30 include a top pulley assembly 31 connecting the top track 14 and the sliding door 20, and a bottom pulley assembly 32 connecting the bottom track 15 and the sliding door 20. In the top pulley assembly 31, the pulley box 40 is fixed to the top of the sliding door 20, the moving wheel assembly 50 is engaged with the top track 14, and the moving wheel assembly 50 is lifted upwards by an elastic member 63 to the top of the sliding door 20. In the bottom pulley assembly 32, the pulley box 40 is fixed to the bottom of the sliding door 20, the moving wheel assembly 50 is engaged with the bottom track 15, and the moving wheel assembly 50 is pushed upwards against the bottom of the pulley box 40 and the sliding door 20 by an elastic member 60. In this embodiment, both the top pulley assembly 31 and the bottom pulley assembly 32 provide upward support to the sliding door 20 in the vertical direction through their elastic members 30; and the top pulley assembly 31 and the bottom pulley assembly 32 are in an adjustable state at any time. By changing the spring pressure of the elastic member 60, the vertical position of the sliding door 20 can be adjusted in the vertical direction.
[0036] On the other hand, each component in the several pulley assemblies 30 is a general-purpose component, which can realize the functions of at least two pulley assemblies by adjusting the direction or installation position of each component. That is, the pulley assembly 30 has at least two forms: a top pulley assembly 31 and a bottom pulley assembly 32. When the pulley assembly 30 is in the form of the top pulley assembly 31, the movable wheel group 50 is located above the pulley box 40 and is used to hold it in place on the top track 14. When the pulley assembly 30 is in the form of the bottom pulley assembly 32, the movable wheel group 50 is located below the pulley box 40 and is used to hold it in place on the bottom track 15.
[0037] The pulley box 40 has a vertically extending box body 41 and a box cover 42, a vertically penetrating slot 43 through the box body 41, and two transverse slots 44 located within the box body 41. The box cover 42 is connected to the box body 41 by screws to form the pulley box 40. The box body 41 of the pulley box 40 has a first short side 411 and a second short side 412 that are parallel to each other, and a first long side 413 and a second long side 414 that connect the first short side 411 and the second short side 412 laterally. The slot 43 penetrates the first short side 411 and the second short side 412 vertically, and the slot 43 is located adjacent to the first long side 413. The two transverse slots 44 include a first transverse slot 441 adjacent to the first short side 411 and a second transverse slot 442 adjacent to the second short side 412.
[0038] In this embodiment, the pulley box 40 is arranged symmetrically vertically, and has a forward position and a reverse position. When the pulley box 40 is in the forward position, the first short side 411 is above the second short side 412; when the pulley box 40 is in the reverse position, the second short side 412 is above the first short side 411. That is, rotating the pulley box 40 180° from its forward position results in its reverse position. The pulley box 40 is designed with a symmetrical structure. By adjusting the left and right directions of the pulley box 40 and the position of the shim 64 of the elastic component 60 within the pulley box 40, a set of general-purpose components can perform the functions of at least two types of pulley assemblies; in this embodiment, four types are used. The pulley box 40 is also provided with at least one hinge hole 45 adjacent to the second long side 414. The pulley assembly 30 also includes a hinge 70 connecting the pulley box 40 and the sliding door 20. One end of the hinge 70 is inserted and fixed in the hinge hole 45 and the other end is fixed to the door leaf 21 of the sliding door 20.
[0039] The movable wheel assembly 50 includes a seat 51 and several movable wheels 52 mounted on the seat 51. The movable wheels 52 can be two, four, or more. In this embodiment, there are four movable wheels 52, arranged in pairs on both longitudinal sides of the seat 51. The seat 51 has a mounting portion 511 extending laterally beyond the first long side 413 and a retaining portion 512 extending vertically from the mounting portion 511. The movable wheels 52 are fixed to the mounting portion 511 and retained on the top track 14 or the bottom track 15. The retaining portion 512 is laterally assembled to the connector 61 of the elastic member 60.
[0040] The elastic component 60 includes a connector 61 connected to the movable wheel assembly 50, a screw 62 housed in the through groove 43, a spring 63 sleeved on the screw 62, and a washer 64 held in the transverse groove 44. The connector 61 is L-shaped and has a connecting seat 611 extending laterally and a protrusion 612 extending vertically from the connecting seat 611. The protrusion 612 at least partially extends into the through groove 43.
[0041] The connecting seat 611 is provided with a slot (unlabeled) extending laterally, and the seat body 51 is provided with a retaining protrusion (unlabeled) protruding outward from both longitudinal sides of the retaining part 512. The retaining part 512 of the seat body 51 is inserted into the connecting seat 611 from one side of the second long side 414 laterally toward one side of the first long side 413. At this time, the retaining protrusion is received in the slot, and the retaining part 512 and the connecting seat 611 are then fixed together by screws.
[0042] The screw 62 extends vertically, with one vertical end connected to the protrusion 612 of the connector 61 and a nut 621 located at the other vertical end. The protrusion 612 is connected to the vertical end of the screw 62 away from the nut 621. One end of the spring 63 abuts against the washer 64, and the other end abuts against the nut 621 or the protrusion 612. The pulley assembly 30 is equipped with the spring 63, which provides support for the door leaf 21 of the sliding door 20 through its elastic force. Furthermore, the screw 62 is threaded to the protrusion 612 of the connector 61, allowing the pulley assembly 30 to be flexibly adjusted and in a readily adjustable state.
[0043] Please see Figures 3 to 6 As shown, the pulley assembly 30 is in the form of the top pulley assembly 31. The movable wheel group 50 is located above the pulley box 40. The connector 61 is connected to the lower part of the movable wheel group 50, and the protrusion 612 extends downward into the through groove 43. The screw 62 is assembled vertically from bottom to top into the through groove 43 and passes through the spring 63 and the washer 64 in sequence until it is connected to the protrusion 612. The washer 64 is disposed adjacent to the protrusion 612, that is, the washer 64 is held in the transverse groove 44 adjacent to the movable wheel group 50.
[0044] The upper end of the spring 63 is connected to the washer 64 and the lower end is connected to the nut 621 of the screw 62. The nut 621 pushes the washer 64 upward via the spring 63, causing the movable wheel assembly 50 to lift and secure the pulley box 40 holding the washer 64 and the movable door 20 connected to the pulley box 40. Specifically, the movable wheel assembly 50 at the top track 14 can provide an upward pulling force to the screw 62, and through the elastic force of the spring 63, the washer 64 can provide an upward supporting force to the pulley box 40, and then the hinge 70 on the pulley box 40 provides an upward supporting force to the door 21. At the same time, in the top pulley assembly 31, by turning the screw 62 to adjust the compression of the spring 63, and thus adjusting the pressure of the spring 63, the vertical position of the door 21 can be adjusted.
[0045] Furthermore, the top pulley assembly 31 can be further divided into a forward-facing top pulley assembly 311 and a reverse-facing top pulley assembly 312. (Combined) Figure 3 and Figure 4 As shown, the top pulley assembly 31 is a forward-facing top pulley assembly 311. At this time, the pulley box 40 is in the forward position, the screw 62 is inserted into the through groove 43 from the second short side 412, and the washer 64 is held in the first transverse groove 441. Combined with... Figure 5 and Figure 6As shown, the top pulley assembly 31 is a reverse top pulley assembly 312, the pulley box 40 is located in the reverse position, the screw 62 is inserted into the through groove 43 from the first short side 411 and the washer 64 is held in the second transverse groove 442. It can be seen that the forward top pulley assembly 311 and the reverse top pulley assembly 312 are symmetrically arranged along the vertical axis.
[0046] Please see Figures 7 to 10 As shown, the pulley assembly 30 is in the form of the bottom pulley assembly 32. The movable wheel group 50 is located below the pulley box 40. The connector 61 is connected to the upper part of the movable wheel group 50, and the protrusion 612 extends upward into the through groove 43. The screw 62 is assembled vertically from top to bottom into the through groove 43 and passes through the washer 64 and the spring 63 in sequence until it is connected to the protrusion 612. The washer 64 is disposed adjacent to the nut 621, that is, the washer 64 is held in the transverse groove 44 away from the movable wheel group 50.
[0047] The upper end of the spring 63 is connected to the washer 64 and the lower end is connected to the protrusion 612 of the connector 61. The protrusion 612 pushes the washer 64 upward via the spring 63, causing the movable wheel assembly 50 to push upward against the pulley box 40 that holds the washer 64 and the movable door 20 connected to the pulley box 40. Specifically, the spring 63 is always in a compressed state, and the movable wheel assembly 50 at the bottom track 15 is always pressed against the bottom track 15. The connector 61 on the movable wheel assembly 50, through the elastic force of the spring 63, enables the washer 64 to provide upward support force to the pulley box 40, and then provides upward support force to the door leaf 21 through the hinge 70 on the pulley box 40.
[0048] Furthermore, the bottom pulley assembly 32 can be further divided into a forward-facing bottom pulley assembly 321 and a reverse-facing bottom pulley assembly 322. (Combined) Figure 7 and Figure 8 As shown, the bottom pulley assembly 32 is a forward-facing bottom pulley assembly 321, the pulley box 40 is in the forward position, the screw 62 is inserted into the through groove 43 from the first short side 411, and the washer 64 is held in the first transverse groove 441. (Combined) Figure 9 and Figure 10 As shown, the bottom pulley assembly 32 is a reverse bottom pulley assembly 322, the pulley box 40 is located in the reverse position, the screw 62 is inserted into the through groove 43 from the second short side 412 and the washer 64 is held in the second horizontal groove 442. It can be seen that the forward bottom pulley assembly 321 and the reverse bottom pulley assembly 322 are symmetrically arranged along the vertical axis.
[0049] In this invention, all components of the pulley assembly 30 are general-purpose components, and the pulley assembly 30 has at least two forms: a top pulley assembly 31 and a bottom pulley assembly 32. When the pulley assembly 30 is in the form of the top pulley assembly 31, the movable wheel group 50 is located above the pulley box 40, the connecting member 61 is connected to the lower part of the movable wheel group 50, the washer 64 is held in the transverse groove 44 adjacent to the movable wheel group 50, and the upper end of the spring 63 is connected to the washer 64 and the lower end is connected to the nut 621 of the screw 62. When the pulley assembly 30 is in the form of the bottom pulley assembly 32, the movable wheel group 50 is located below the pulley box 40, the connecting member 61 is connected to the upper part of the movable wheel group 50, the washer 64 is held in the transverse groove 44 away from the movable wheel group 50, and the upper end of the spring 63 is connected to the washer 64 and the lower end is connected to the connecting member 61. All components of the pulley assembly 30 are universal components, and at least two pulley assembly functions can be achieved by adjusting the direction or installation position of each component.
[0050] In summary, the above are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Any simple equivalent changes and modifications made in accordance with the claims and description of the present utility model should still fall within the scope of the present utility model patent.
Claims
1. A pulley assembly for connecting between a door frame and a moving door, the pulley assembly comprising a pulley box, a moving pulley set moving vertically relative to the pulley box, and an elastic component connected between the pulley box and the moving pulley set, the pulley box being provided with a box body extending vertically, a through slot extending vertically through the box body, and two transverse slots in the box body, the elastic component comprising a connecting piece connected to the moving pulley set, a screw rod received in the through slot, a spring sleeved on the screw rod, and a gasket clamped in the transverse slots, a vertical one end of the screw rod being connected to the connecting piece and being provided with a nut at a vertical other end; characterized in that: The pulley assembly is composed of common parts, and has two configurations, i.e. a top pulley assembly and a bottom pulley assembly. When the pulley assembly is in the top pulley assembly configuration, the moving wheel set is located above the pulley box, the connecting piece is connected below the moving wheel set, the gasket is clamped in the horizontal slot adjacent to the moving wheel set, and the upper end of the spring is connected to the gasket and the lower end is connected to the nut of the screw rod. When the pulley assembly is in the bottom pulley assembly configuration, the moving wheel set is located below the pulley box, the connecting piece is connected above the moving wheel set, the gasket is clamped in the horizontal slot away from the moving wheel set, and the upper end of the spring is connected to the gasket and the lower end is connected to the connecting piece.
2. The pulley assembly of claim 1, wherein: The connecting piece is provided with a protruding part extending into the through slot, the protruding part is connected to the vertical end of the screw rod away from the nut, and one end of the spring is connected to the gasket and the other end is connected to the nut or the protruding part.
3. The pulley assembly of claim 2, wherein: When the pulley assembly is in the top pulley assembly configuration, the protruding part extends downward into the through slot, the screw rod is assembled into the through slot in the vertical direction from bottom to top and sequentially passes through the spring and the gasket until connected to the protruding part, the gasket is arranged adjacent to the protruding part, and the upper end of the spring is connected to the gasket and the lower end is connected to the nut of the screw rod.
4. The pulley assembly of claim 2, wherein: When the pulley assembly is in the bottom pulley assembly configuration, the protruding part extends upward into the through slot, the screw rod is assembled into the through slot in the vertical direction from top to bottom and sequentially passes through the gasket and the spring until connected to the protruding part, the gasket is arranged adjacent to the nut, and the upper end of the spring is connected to the gasket and the lower end is connected to the protruding part of the connecting piece.
5. The pulley assembly of claim 1, wherein: The pulley box is provided with a first short side and a second short side parallel to each other, and a first long side and a second long side connected to the lateral sides of the first short side and the second short side, the through slot penetrates the first short side and the second short side in the vertical direction, and the through slot is arranged adjacent to the first long side, and the two horizontal slots include a first horizontal slot adjacent to the first short side and a second horizontal slot adjacent to the second short side.
6. The pulley assembly of claim 5, wherein: The pulley box is arranged symmetrically in the vertical direction, and has a forward position and a reverse position, when the pulley box is in the forward position, the first short side is located above the second short side, and when the pulley box is in the reverse position, the second short side is located above the first short side.
7. The pulley assembly of claim 6, wherein: The top pulley assembly is further divided into a forward top pulley assembly and a reverse top pulley assembly, in the forward top pulley assembly, the pulley box is in the forward position, the screw rod is inserted into the through slot from the second short side, and the gasket is clamped in the first horizontal slot, and in the reverse top pulley assembly, the pulley box is in the reverse position, the screw rod is inserted into the through slot from the first short side, and the gasket is clamped in the second horizontal slot.
8. The pulley assembly of claim 6, wherein: The bottom pulley assembly is further divided into a forward bottom pulley assembly and a reverse bottom pulley assembly; in the forward bottom pulley assembly, the pulley box is located at a forward position, the screw rod is inserted into the through slot from the first short side, and the gasket is clamped in the first horizontal slot; in the reverse bottom pulley assembly, the pulley box is located at a reverse position, the screw rod is inserted into the through slot from the second short side, and the gasket is clamped in the second horizontal slot.
9. The pulley assembly of claim 5, wherein: The connecting piece is provided in an L shape and is provided with a connecting seat extending in the lateral direction and a protruding portion extending in the vertical direction from the connecting seat, the protruding portion extending partially into the through slot, the moving wheel set is provided with a seat body and a plurality of moving wheels mounted on the seat body, the seat body is provided with a mounting portion extending in the lateral direction beyond the first long side and a clamping portion extending in the vertical direction from the mounting portion, the moving wheels being held on the mounting portion, and the clamping portion being assembled in the lateral direction to the connecting seat of the connecting piece.
10. The pulley assembly of claim 9, wherein: The connecting seat is provided with a slot extending in the lateral direction, the seat body is provided with clamping protrusions protruding outward from the longitudinal sides of the clamping portion, and the clamping portion of the seat body is inserted in the lateral direction from one side of the second long side to one side of the first long side to the connecting seat; at this time, the clamping protrusions are accommodated in the slot, and the clamping portion and the connecting seat are fixed together by screw connection.