阅读说明：本技术 两用鞋及其折叠式滑轮装置 (Dual-purpose shoes and folding pulley device thereof ) 是由 肖仁强 于 2019-12-12 设计创作，主要内容包括：本发明公开一种折叠式滑轮装置,包括前轮架、后轮架、壳座、联动架和开关机构,开关机构包括锁紧动轴,联动架的前、中、后端分别水平且平行地安装有传动前轴、中定轴和传动后轴,联动架设有与锁紧动轴配合的收合卡孔和展开卡孔,壳座水平且平行地安装有第一旋转定轴和第二旋转定轴,壳座上还设有横向限位孔、竖向限位孔、第一弧形限位孔及第二弧形限位孔,中定轴与第一旋转定轴之间有复位拉簧,前轮架的左右两端与第一旋转定轴和传动前轴相连接,后轮架的左右两端与第二旋转定轴和传动后轴相连接。本发明通过开关机构可使其锁紧动轴在收合卡孔和展开卡孔之间切换并实现折叠式滑轮装置的收合状态和展开状态的保持,安全、稳定、可靠。(The invention discloses a folding pulley device, which comprises a front wheel frame, a rear wheel frame, a shell seat, a linkage frame and a switching mechanism, wherein the switching mechanism comprises a locking moving shaft, the front end, the middle end and the rear end of the linkage frame are respectively provided with a transmission front shaft, a middle fixed shaft and a transmission rear shaft horizontally and parallelly, the linkage frame is provided with a folding clamping hole and an unfolding clamping hole which are matched with the locking moving shaft, the shell seat is horizontally and parallelly provided with a first rotating fixed shaft and a second rotating fixed shaft, the shell seat is also provided with a transverse limiting hole, a vertical limiting hole, a first arc limiting hole and a second arc limiting hole, a reset tension spring is arranged between the middle fixed shaft and the first rotating fixed shaft, the left end and the right end of the front wheel frame are connected with the first rotating fixed shaft and the transmission front shaft, and the left end and the right end of the rear wheel frame are connected with the second rotating fixed shaft and the transmission. The invention can switch the locking moving shaft between the folding clamping hole and the unfolding clamping hole through the opening and closing mechanism and realize the maintenance of the folding state and the unfolding state of the folding pulley device, thereby being safe, stable and reliable.)

1. Foldable pulley gear, its characterized in that: the front end and the rear end of the linkage frame are respectively provided with a transmission front shaft, a middle fixed shaft and a transmission rear shaft horizontally and parallelly, the front end and the rear end of the top surface of the linkage frame are respectively provided with a folding clamping hole and an unfolding clamping hole which are respectively matched with the locking movable shaft at intervals, the front end and the rear end of the shell seat are respectively provided with a first rotating fixed shaft and a second rotating fixed shaft horizontally and parallelly, the shell seat is also respectively provided with a transverse limiting hole for limiting the front-rear movement of the middle fixed shaft, a vertical limiting hole for limiting the vertical movement of the locking movable shaft, a first arc limiting hole for limiting the rotation of the transmission front shaft around the central line of the first rotating fixed shaft and a second arc limiting hole for limiting the rotation of the transmission rear shaft around the central line of the second rotating fixed shaft, a reset tension spring is connected between the middle fixed shaft and the first rotating fixed shaft, the left end and the right end of the front wheel frame are respectively connected with the first rotating fixed shaft and the transmission front shaft, and the left end and the right end of the rear wheel frame are respectively connected with the second rotating fixed shaft and the transmission rear shaft.

2. The folding pulley apparatus of claim 1, wherein: the shell seat is composed of a shell cover and a shell seat main body which is integrally formed by injection molding, the transverse limiting hole, the vertical limiting hole, the first arc-shaped limiting hole, the second arc-shaped limiting hole, the first rotating fixed shaft and the second rotating fixed shaft are all arranged on the shell seat main body, and the shell cover is sealed at an opening of the installation cavity.

3. The folding pulley apparatus of claim 2, wherein: the first arc-shaped limiting hole is located below the first rotating fixed shaft, the second arc-shaped limiting hole is located above the second rotating fixed shaft, and the front wheel frame and the rear wheel frame move in opposite directions when the front wheel frame and the rear wheel frame are folded.

4. The folding pulley apparatus of claim 1, wherein: the switch mechanism further comprises a guide seat, a sliding block, a pressure spring and a trigger rod, wherein the guide seat is fixedly arranged in the mounting cavity and is provided with a sliding rail arranged along the front-back direction of the shell seat, the sliding block is in sliding fit with the sliding rail, and the sliding block is provided with a clamping groove for driving the locking moving shaft to move up and down along the vertical limiting hole; the pressure spring is installed between the front end of the sliding block and the guide seat, the front end of the trigger rod acts on one end, far away from the pressure spring, of the sliding block, and the rear end of the trigger rod is exposed behind the shell seat.

5. The folding pulley apparatus of claim 4, wherein: the draw-in groove comprises horizontal screens groove and the arc lift groove of intercommunication each other, horizontal screens groove is located the place ahead in arc lift groove, the height in arc lift groove is higher than the linkage frame top surface.

6. The folding pulley apparatus of claim 4, wherein: and the front end of the sliding block and the guide seat are respectively provided with an embedding hole matched with the pressure spring at the position corresponding to the pressure spring.

7. The folding pulley apparatus of claim 4, wherein: the rear end of the sliding block is provided with a T-shaped clamping hole which is wide in front and narrow in back, the front end of the trigger rod is provided with a T-shaped head matched with the T-shaped clamping hole, and the T-shaped head can rotate around a self-axis in the T-shaped clamping hole by rotating the trigger rod; the utility model discloses a safety device, including shell seat, trigger bar, safety hole, safety piece, shell seat rear end is equipped with the perforation that supplies the trigger bar to wear to establish and fenestrate one side intercommunication is provided with the safety hole, the trigger bar rear end be equipped with safety hole assorted safety piece, only can wear to establish the activity in the perforation around the trigger bar after safety piece corresponds the cooperation with the safety hole.

8. The folding pulley apparatus of claim 4, wherein: the front end and the rear end of the guide seat in the installation cavity are respectively provided with a front stop block and a rear stop block in a protruding mode, a limiting lug is arranged between the front stop block and the rear stop block in a protruding mode, a matching notch is formed in the position, corresponding to the limiting lug, of the guide seat, and the guide seat is fixedly installed in the installation cavity between the front stop block and the rear stop block through a fastening piece or a bonding body.

9. The folding pulley apparatus of claim 8, wherein: the left side and the right side of the guide seat are respectively provided with a supporting shoulder strip matched with the linkage frame support, and a supporting convex block matched with the linkage frame support is convexly arranged in the front part of the installation cavity.

10. Dual-purpose shoes, characterized by that, include the sole and foldable pulley gear of any claim 1 to 9, the said foldable pulley gear is installed on the sole, there are recesses to hold front wheel carrier and back wheel carrier after closing respectively on the left and right sides of the middle part of the said sole, the said sole rear end has matching holes for the opening and closing mechanism to stretch out, the said shell seat top surface is flush with the corresponding place of sole top surface.

Technical Field

The invention belongs to the technical field of footwear products, and particularly relates to a dual-purpose shoe and a folding type pulley device thereof.

Background

The dual-purpose shoe comprises a sole with a pulley device, and the switching between two use working conditions of sliding and walking can be realized by changing the different installation states of the pulley device on the sole. The existing dual-purpose shoes generally comprise a front wheel frame positioned at the front part of a sole and a rear wheel frame positioned at the rear part of the sole, wherein a retaining mechanism of the front wheel frame and the rear wheel frame in an unfolding or folding using state is respectively clamped with a locking shaft on a control mechanism when a swing arm is folded in place and unfolded in place through two clamping holes arranged on the swing arm, and the locking shaft is generally clamped with the corresponding clamping holes through the compression action of a torsion spring. However, the locking shaft and the clamping hole are kept clamped under the action of the torsion spring, so that once the torsion spring fails or the compression action is reduced, the front wheel frame and the rear wheel frame are easy to shake, and even the safety accident caused by automatic and sudden switching in the use process is caused.

Disclosure of Invention

The invention aims to provide a safe, stable and reliable folding pulley device.

In order to solve the technical problems, the invention adopts the technical scheme that:

the folding pulley device comprises a front wheel frame, a rear wheel frame, a shell seat with an installation cavity, a linkage frame and a switch mechanism, wherein the linkage frame and the switch mechanism are respectively arranged in the installation cavity, the switch mechanism comprises a locking moving shaft arranged along the left and right directions of the shell seat, the front end, the middle end and the rear end of the linkage frame are respectively provided with a transmission front shaft, a middle fixed shaft and a transmission rear shaft in a horizontal and parallel mode, the top surface of the linkage frame is provided with a folding clamping hole and an unfolding clamping hole which are respectively matched with the locking moving shaft at intervals in the front and at the back, the front end and the rear end of the shell seat are respectively provided with a first rotating fixed shaft and a second rotating fixed shaft in a horizontal and parallel mode, the shell seat is also respectively provided with a horizontal limiting hole for limiting the front and back movement of the middle fixed shaft, a vertical limiting hole for limiting the up and down movement of the locking moving shaft, a first arc limiting hole for limiting the rotation of the transmission front shaft around the central line of the first rotating fixed shaft, a reset tension spring is connected between the middle fixed shaft and the first rotating fixed shaft, the left end and the right end of the front wheel frame are respectively connected with the first rotating fixed shaft and the transmission front shaft, and the left end and the right end of the rear wheel frame are respectively connected with the second rotating fixed shaft and the transmission rear shaft.

Preferably, the shell seat comprises a shell cover and a shell seat main body integrally formed by injection molding, the transverse limiting hole, the vertical limiting hole, the first arc-shaped limiting hole, the second arc-shaped limiting hole, the first rotating fixed shaft and the second rotating fixed shaft are all arranged on the shell seat main body, and the shell cover is sealed at an opening of the installation cavity.

Preferably, the first arc-shaped limiting hole is located below the first rotating fixed shaft, the second arc-shaped limiting hole is located above the second rotating fixed shaft, and the front wheel frame and the rear wheel frame move in opposite directions when the front wheel frame and the rear wheel frame are folded.

Preferably, the switch mechanism further comprises a guide seat, a sliding block, a pressure spring and a trigger rod, wherein the guide seat is fixedly arranged in the mounting cavity and provided with a sliding rail arranged along the front-back direction of the shell seat, the sliding block is in sliding fit with the sliding rail, and the sliding block is provided with a clamping groove for driving the locking moving shaft to move up and down along the vertical limiting hole; the pressure spring is installed between the front end of the sliding block and the guide seat, the front end of the trigger rod acts on one end, far away from the pressure spring, of the sliding block, and the rear end of the trigger rod is exposed behind the shell seat.

Preferably, the draw-in groove comprises horizontal screens groove and the arc lift groove of intercommunication each other, horizontal screens groove is located the place ahead in arc lift groove, the height in arc lift groove is higher than the linkage frame top surface.

Preferably, the front end of the sliding block and the guide seat are respectively provided with an embedding hole matched with the pressure spring at the position corresponding to the pressure spring.

Preferably, the rear end of the sliding block is provided with a T-shaped clamping hole which is wide in front and narrow in back, the front end of the trigger rod is provided with a T-shaped head matched with the T-shaped clamping hole, and the T-shaped head can rotate around a self-axis in the T-shaped clamping hole by rotating the trigger rod; the utility model discloses a safety device, including shell seat, trigger bar, safety hole, safety piece, shell seat rear end is equipped with the perforation that supplies the trigger bar to wear to establish and fenestrate one side intercommunication is provided with the safety hole, the trigger bar rear end be equipped with safety hole assorted safety piece, only can wear to establish the activity in the perforation around the trigger bar after safety piece corresponds the cooperation with the safety hole.

Preferably, a front stop block and a rear stop block are respectively and convexly arranged at the front end and the rear end of the installation cavity corresponding to the guide seat, a limiting convex block is convexly arranged between the front stop block and the rear stop block, a matching notch is arranged at the position of the guide seat corresponding to the limiting convex block, and the guide seat is fixedly installed in the installation cavity between the front stop block and the rear stop block through a fastening piece or a bonding body.

Preferably, the left side and the right side of the guide seat are respectively provided with a support shoulder strip matched with the linkage frame support, and a support convex block matched with the linkage frame support is convexly arranged in the front part of the installation cavity.

The invention also provides a pair of dual-purpose shoes, which comprise soles and the folding pulley devices, wherein the folding pulley devices are arranged on the soles, the left side and the right side of the middle parts of the soles are respectively provided with notches for accommodating the folded front wheel frames and the folded rear wheel frames, the rear ends of the soles are provided with matching holes for extending the opening and closing mechanisms, and the top surfaces of the shell seats are flush with the corresponding positions of the top surfaces of the soles.

Compared with the prior art, the invention has the following beneficial effects:

the foldable pulley device comprises a shell seat, a linkage frame, an opening and closing mechanism, a front wheel frame and a rear wheel frame, wherein the left end and the right end of the front wheel frame and the right end of the rear wheel frame are respectively connected with the linkage frame, the front wheel frame and the rear wheel frame can be synchronously folded or unfolded through the linkage frame, a folding clamping hole and an unfolding clamping hole are formed in the linkage frame, and a locking moving shaft of the locking frame can be switched between the folding clamping hole and the unfolding clamping hole through the opening and closing mechanism to keep the folding state and the unfolding state of the foldable pulley device. And the folding clamping holes and the unfolding clamping holes are arranged on the linkage frame in the shell seat, and the folding clamping holes and the unfolding clamping holes are protected by the shell seat after being assembled with the sole for use and are not easily influenced by external environmental factors, external force and the like, so that the use performance is not easily influenced, and the locking stability in the folding and unfolding states is ensured.

In addition, the action of the pressure spring on the sliding block can be almost ignored when the device is unfolded or folded for use, the service life of the pressure spring is long, the front wheel frame and the rear wheel frame cannot be suddenly switched even if the pressure spring fails, and the safety performance is greatly improved; the action of the pressure spring is only to help the sliding block to automatically reset to the lower end of the clamping groove to limit the pressing of the locking moving shaft after the locking moving shaft is clamped into the unfolding clamping hole or the folding clamping hole, and the sliding block can be reset by drawing the trigger rod through external force even if the pressure spring fails.

Drawings

Fig. 1 is an exploded view of the folding pulley apparatus of the present invention.

Fig. 2 is an external view showing an unfolded state of the folding pulley device according to the present invention.

Fig. 3 is a schematic view of the internal structure of the foldable pulley device according to the present invention in an unfolded state.

Fig. 4 is an external view of the foldable pulley device according to the present invention in a folded state.

Fig. 5 is a schematic view of the internal structure of the foldable pulley device in a folded state according to the present invention.

FIG. 6 is a schematic view of a linkage plate structure according to the present invention.

FIG. 7 is a schematic view of a linkage plate with a mounting hole according to the present invention.

Fig. 8 is a schematic structural view of a preferred embodiment of a slot on a slider according to the present invention (arrows in the figure point forward).

The labels in the figure are: 10. a housing base; 11. a shell cover; 12. a housing base body; 13. a first rotating fixed shaft; 14. a second rotating fixed shaft; 100. installing a chamber; 101. a first arc-shaped limiting hole; 102. a second arc-shaped limiting hole; 103. a vertical limiting hole; 104. a transverse limiting hole; 105. perforating; 106. a front stop block; 107. a rear stop block; 108. a restraining bump; 109. supporting the projection; 20. a front wheel carrier; 21. swinging arms; 30. a rear wheel carrier; 31. swinging arms; 40. a linkage frame; 41. a linkage plate; 42. a transmission front shaft; 43. a rear transmission shaft; 44. a central fixed shaft; 45. mounting holes; 401. unfolding the clamping hole; 402. closing the clamping hole; 50. a switch mechanism; 51. a guide seat; 52. a slider; 53. a pressure spring; 54. a trigger lever; 55. locking the moving shaft; 521. a transverse clamping groove; 522. an arc-shaped lifting groove; 60. a return tension spring; 800. a folding pulley device; 900. a sole; 901. a recess.

Detailed Description

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

As shown in fig. 1 to 8, the present embodiment provides a folding pulley apparatus 800 including a front wheel frame 20, a rear wheel frame 30, a housing 10, a linkage frame 40 and an opening and closing mechanism 50.

In this embodiment, the housing 10 is composed of a housing cover 11 and a housing body 12 formed by injection molding, a mounting chamber 100 for mounting the linkage frame 40 and the switch mechanism 50 is disposed in the housing body 12, as shown in fig. 1, the mounting chamber 100 is a long cavity extending in the front-back direction and having an upper opening, and the housing cover 11 is adapted to be mounted and sealed at the upper opening of the mounting chamber 100 and preferably has a cambered surface matching with the radian of the sole of the foot. The installation cavity 100 is provided with a bottom cavity wall, a front side wall, a rear side wall, a left side wall and a right side wall, wherein the front side wall, the rear side wall, the left side wall and the right side wall are vertically and upwards connected with the bottom cavity wall, the front side wall, the rear side wall, the left side wall and the right side wall are symmetrically provided with a transverse limiting hole 104, a vertical limiting hole 103, a first arc-shaped limiting hole 101 and a second arc-shaped limiting hole 102, meanwhile, a first rotating fixed shaft 13 is horizontally arranged between the left side wall and the right side wall above the first arc-shaped limiting hole 101, a second rotating fixed shaft 14 is horizontally arranged between the left side wall and the right side wall below the second arc-shaped limiting hole 102, the first arc-shaped limiting hole 101 takes the end part of the first rotating fixed shaft 13 as a rotating circle center, the second arc-shaped limiting hole 102 takes the end part of.

In this embodiment, the switch mechanism 50 includes a guide holder 51, a slider 52, a compression spring 53, a trigger lever 54, and a lock shaft 55 arranged in the left-right direction of the housing holder 10, the guide seat 51 is fixedly installed in the installation chamber 100 and provided with a slide rail arranged along the front-rear direction of the housing seat 10, the sliding block 52 is in sliding fit with the sliding rail and is positioned between the vertical limiting holes 103 on the left side wall and the right side wall, the slide block 52 is provided with a clamping groove for driving the locking moving shaft 55 to move up and down along the vertical limiting hole 103, the locking moving shaft 55 horizontally passes through the clamping groove and two ends of the locking moving shaft are abutted against the outer end faces of the left side wall and the right side wall through limiting heads, the compression spring 53 is arranged between the front end of the slide block 52 and the guide seat 51, the front end of the trigger rod 54 acts on one end of the slide block 52 far away from the compression spring 53, the rear end of the trigger rod 54 is exposed at the rear of the housing base 10, and a through hole 105 for the trigger rod 54 to move back and forth is formed in the position of the rear side wall corresponding to the trigger rod 54. Therefore, the trigger rod 54 is extruded by external force, the sliding block 52 is enabled to move forwards along the guide seat 51 while the pressure spring 53 is compressed, the sliding block 52 moves forwards while the locking moving shaft 55 moves upwards along the vertical limiting hole 103 by utilizing the clamping groove to be separated from the folding clamping hole 402 or the unfolding clamping hole 401 on the linkage frame 40, and the locking moving shaft 55 is limited by the vertical limiting hole 103 to move up and down.

The installation structure of the pressure spring 53 can specifically adopt the following: the front end of the sliding block 52 and the guide seat 51 are respectively provided with an insertion hole matched with the pressure spring 53 at the position corresponding to the pressure spring 53, and two ends of the pressure spring 53 are respectively inserted into the insertion hole on the sliding block 52 and the insertion hole on the guide seat 51, so that the pressure spring 53 can be always kept in the moving direction of the trigger rod 54 in the compression and rebound processes, and the trigger rod 54 and the sliding block 52 can be smoothly reset by utilizing the rebound acting force of the pressure spring 53 after external force is removed, and the locking moving shaft 55 can be limited in the folding clamping hole 402 or the unfolding clamping hole 401 by utilizing a clamping groove on the sliding block 52.

In order to enhance the limiting effectiveness and stability of the locking shaft 55 by the card slot, the card slot of the present embodiment may specifically adopt the following manner: as shown in fig. 8, the locking slot is composed of a transverse locking slot 521 and an arc-shaped lifting slot 522 which are communicated with each other, the transverse locking slot 521 is located in front of the arc-shaped lifting slot 522, the height of the arc-shaped lifting slot 522 is higher than the top surface of the linkage frame 40, after the sliding block 52 is extruded forwards, the arc-shaped lifting slot 522 is used for providing upward component force to the locking moving shaft 55, so that the locking moving shaft 55 can move upwards along the vertical limiting hole 103 to separate from the folded locking hole 402 or the unfolded locking hole 401, and after the external force to the trigger lever 54 is removed, the sliding block 52 is reset, that is, the transverse locking slot 521 is used for well limiting the locking moving shaft 55 in the folded locking hole 402 or the unfolded. Preferably, the front-back length L of the lateral locking groove 521 is greater than the outer diameter D of the locking shaft 55 at the position of the lateral locking groove 521, for example, L is 1.5-2.5 times of D.

The mounting structure of the guide holder 51 may specifically adopt the following: a front stop block 106 and a rear stop block 107 are respectively and convexly arranged at the front end and the rear end of the installation cavity 100 corresponding to the guide seat 51, a limiting convex block 108 is convexly arranged between the front stop block 106 and the rear stop block 107, a matching notch is arranged at the position of the guide seat 51 corresponding to the limiting convex block 108, and the guide seat 51 is fixedly installed in the installation cavity 100 between the front stop block 106 and the rear stop block 107 through a fastener or a bonding body. The slide rail on the guide base 51 is preferably formed of a dovetail block, and is a dovetail rail; the left side and the right side of the guide seat 51 are respectively provided with a supporting shoulder strip which is in supporting fit with the linkage frame 40, and the front part of the installation cavity 100 is internally provided with a supporting convex block 109 which is in supporting fit with the linkage frame 40.

In addition, to avoid accidents, the mounting structure of the triggering lever 54 and the sliding block 52 can be specifically as follows: the rear end of slider 52 is equipped with the T type card hole of preceding wide back narrow, the front end of trigger bar 54 is established to the T type head with T type card hole assorted, and rotatory trigger bar 54 can make T type head is downthehole around from the rotation of axes in T type card, one side intercommunication of perforation 105 is provided with the safety vent, the rear end of trigger bar 54 is equipped with the safety block with safety vent assorted, only can trigger bar 54 wear to establish the activity in perforation 105 in the front and back after safety block corresponds the cooperation with the safety vent.

In this embodiment, the linkage frame 40 includes two linkage plates 41, and a transmission front shaft 42, a middle fixed shaft 44, and a transmission rear shaft 43 respectively horizontally and parallelly installed at front, middle, and rear ends of the two linkage plates 41, both ends of the transmission front shaft 42 pass through first arc-shaped limiting holes 101 of the corresponding sides, both ends of the transmission rear shaft 43 pass through second arc-shaped limiting holes 102 of the corresponding sides, both ends of the middle fixed shaft 44 pass through the transverse limiting holes 104 and abut against outer end faces of left and right side walls through limiting heads to realize that the middle fixed shaft 44 is limited by the transverse limiting holes 104 to move back and forth, in addition, a reinforcing shaft for reinforcing the stability of the assembly structure of the two linkage plates 41 may be further horizontally installed on the linkage frame 40 at one side of the transmission rear shaft 43, and the linkage plate 41 is provided with an installation hole 45 for installing the reinforcing shaft. Two ganged plates 41 paste and lean on left side wall and right side wall setting, just the interval is provided with respectively with locking moving axis 55 complex receipts and close card hole 402 and expand card hole 401 around the ganged plate 41 top surface, expands card hole 401 and receive the card hole 402 rear in receipts, be connected with the extension spring that resets 60 between well dead axle 44 and the first rotatory dead axle 13.

The front wheel frame 20 and the rear wheel frame 30 of this embodiment each include two wheel bodies, a synchronizing shaft horizontally installed on the two wheel bodies in a penetrating manner, and two swing arms 21 and 31 respectively hinged to corresponding end portions of the synchronizing shaft, the left and right ends of the front wheel frame 20, that is, the top ends of the two swing arms 21 located at the left and right sides, are respectively connected to the first rotating fixed shaft 13 and the transmission front shaft 42, and the left and right ends of the rear wheel frame 30, that is, the top ends of the two swing arms 31 located at the left and right sides, are respectively connected to the second rotating fixed shaft 14 and the transmission rear shaft 43. Since the first arc-shaped hole 101 is located below the first rotating shaft 13 and the second arc-shaped hole 102 is located above the second rotating shaft 14, the front wheel frame 20 and the rear wheel frame 30 move toward each other when folded, and the front wheel frame 20 and the rear wheel frame 30 move away from each other when unfolded. In the folding and opening process, the transmission front shaft 42 rotates around the center line of the first rotating fixed shaft 13 in the first arc-shaped limiting hole 101, and the transmission rear shaft 43 rotates around the center line of the second rotating fixed shaft 14 in the second arc-shaped limiting hole 102.

The operation process of the folding pulley device 800 of the present embodiment is as follows:

firstly, folding process: rotating the trigger bar 54 until the safety block faces the safety hole, forward pressing the trigger bar 54 to lift the locking shaft 55 upward and leave the unfolding clamping hole 401, at this time, the external force makes the rear wheel frame 30 swing forward or makes the front wheel frame 20 swing backward, because the linkage frame 40 makes the front wheel frame 20 and the rear wheel frame 30 synchronously and oppositely folded, the return tension spring 60 is lengthened, and the linkage frame 40 is backward; when the front wheel frame 20 and the rear wheel frame 30 are completely folded in place, the locking moving shaft 55 is just clamped into the folding clamping hole 402, and the middle fixed shaft 44 moves to the rear end of the transverse limiting hole 104, and the compression spring 53 acts to reset the sliding block 52 and limit the locking moving shaft 55 in the folding clamping hole 402 to keep the folded state.

Secondly, unfolding process: rotating the trigger rod 54 until the safety block faces the safety hole, forward pressing the trigger rod 54 to lift the locking moving shaft 55 upward and leave the folding clamping hole 402, at this time, using the pulling force of the reset tension spring 60 to automatically pull the linkage frame 40 forward, and synchronously spreading the front wheel frame 20 and the rear wheel frame 30 away from each other; after the locking shaft 55 is unfolded in place, the middle fixed shaft 44 moves to the front end of the transverse limiting hole 104, the locking shaft 55 is clamped into the unfolding clamping hole 401, the sliding block 52 is reset under the action of the compression spring 53, and the locking shaft 55 is limited in the unfolding clamping hole 401 to keep an unfolded state.