CN106671711B

CN106671711B - Traction hook and traction device

Info

Publication number: CN106671711B
Application number: CN201611170234.6A
Authority: CN
Inventors: 刘虎; 敖珊
Original assignee: Jost China Auto Component Co Ltd
Current assignee: Jost China Auto Component Co Ltd
Priority date: 2016-12-16
Filing date: 2016-12-16
Publication date: 2023-05-16
Anticipated expiration: 2036-12-16
Also published as: CN106671711A

Abstract

The invention provides a draw hook and draw gear, draw hook pass one have through-hole draw ring in order to connect with said draw ring through a lockpin, draw hook include: a mechanical connection assembly; the air pressure control assembly comprises an air pressure control device, an air passage connecting pipe and an air bag, wherein the air passage connecting pipe is respectively connected with the air pressure control device and the air bag; the hydraulic pressing assembly comprises a first hydraulic cavity, a second hydraulic cavity, a linkage assembly and a pressing rod, wherein the first hydraulic cavity is communicated with the second hydraulic cavity, when a lock pin penetrates through a through hole of a traction ring, the air pressure control device inflates the air bag, the volume of the air bag is increased, liquid in the first hydraulic cavity flows to the second hydraulic cavity, the linkage assembly pushes the pressing rod to one end of a mechanical connecting assembly, and the pressing rod is abutted to the end part of the traction ring. The traction hook provided by the invention can prolong the service life of the traction hook.

Description

Traction hook and traction device

Technical Field

The invention relates to the field of trailer connection, in particular to a traction hook and a traction device.

Background

In the prior art, the traction hook is a tool used when a trailer is needed, the traction hole is positioned at the front part of the trailer, the cover plate of the traction hole is pried by a tool such as a screwdriver, and then the traction hook is inserted into the traction hole for tightening, so that the firmness is ensured, and a tire wrench can be sleeved into the traction hook for tightening. There are other types of hitch devices that have been widely used in the field of towing a variety of trailers by a tractor, most of which include a combination of a first connecting portion that is coupled to one vehicle and a second connecting member that is coupled to another vehicle. For practical connection, when the vehicle is connected, the alignment of the connecting parts is required, and the firm connection of the trailer connecting parts is required, so that the combination mode of the connecting parts is critical.

One prior art attachment is that the locking pin of the towing hook is passed through a through hole in the towing loop to attach the towing hook and the towing loop together. When the common traction ring is matched with the lock pin for installation, a gap exists between the traction ring and the lock pin. In the running process of the vehicle, due to the existence of a gap and the change of the speed of the vehicle, impact force exists between the traction ring and the lock pin, and the situation is more serious when liquid articles are transported, so that abnormal vibration between the traction hook and the traction ring is caused, abrasion is increased, and the service life is shortened.

Disclosure of Invention

The invention aims to provide a traction hook and a traction device, which overcome the difficulty in the prior art and can prolong the service life of the traction hook and the traction ring.

According to one aspect of the present invention, there is provided a towing hook which passes through a towing ring having a through hole by a lock pin to be connected with the towing ring, the towing hook comprising:

a mechanical linkage assembly for controlling movement of the locking pin;

the air pressure control assembly comprises an air pressure control device, an air passage connecting pipe and an air bag, wherein the air pressure control device is arranged at one end of the mechanical connecting assembly, which is provided with the lock pin, the air bag is arranged at the other end of the mechanical connecting assembly, and the air passage connecting pipe is respectively connected with the air pressure control device and the air bag;

the hydraulic pressing component comprises a first hydraulic cavity, a second hydraulic cavity, a linkage component and a pressing rod, wherein the first hydraulic cavity is communicated with the second hydraulic cavity and is arranged at the other end of the mechanical connecting component, the air bag is positioned in the first hydraulic cavity, liquid is filled between the air bag and the first hydraulic cavity, one end of the linkage component is connected with the second hydraulic cavity, the other end of the linkage component is opposite to one end of the pressing rod,

when the lock pin passes through the through hole of the traction ring, the air pressure control device inflates the air bag through the air passage connecting pipe, the volume of the air bag is increased, so that liquid in the first hydraulic cavity flows to the second hydraulic cavity, the linkage assembly pushes the pressing rod to one end of the mechanical connection assembly, and the pressing rod abuts against the end part of the traction ring:

when the lock pin moves out of the through hole of the traction ring, the air pressure control device reduces the air pressure in the air bag connected with the air path connecting pipe, the air bag reduces in volume so that liquid in the second hydraulic cavity flows to the first hydraulic cavity, the pressure in the second hydraulic cavity is reduced, the linkage assembly moves away from one end of the mechanical connection assembly, and the pressing rod is not abutted against the end of the traction ring.

Optionally, the mechanical connection assembly comprises:

the traction shaft is provided with a sixth through hole penetrating through the axial direction of the traction shaft;

the horn mouth is provided with an opening end and a closing end, the opening size of the opening end is larger than that of the closing end, the closing end is connected with one end of the traction shaft, the closing end is provided with two opposite end faces, a locking space is formed between the two opposite end faces, and the opening end is arranged back to the traction shaft;

the driving mechanism is provided with a driving device and a driving mechanism shell for accommodating the driving device, the driving mechanism shell forms an accommodating space communicated with the locking space, and the driving device controls the lock pin to move between the accommodating space and the locking space.

Optionally, the driving mechanism is mounted at one end of the traction shaft, and the driving device includes:

a handle and a trigger plate within the drive mechanism housing, the handle having an extension shaft portion extending through a first end of the trigger plate, the trigger plate rotatable with the extension shaft portion, a second end of the trigger plate abutting the locking pin,

the handle is rotated to drive the extension shaft part to rotate, the extension shaft part drives the trigger plate to rotate, and the second end of the trigger plate controls the lock pin to move up and down so as to be connected with and disconnected from the traction ring.

Optionally, the air pressure control device is installed in a driving mechanism shell of the driving mechanism, and the air bag is installed at the other end of the traction shaft.

Optionally, the air pressure control assembly further comprises: and the inflation control switch is used for controlling the air pressure control device and is arranged in a driving mechanism shell of the driving mechanism, wherein when the handle is rotated to enable the trigger plate to rotate and control the lock pin to pass through the through hole of the traction ring, the trigger plate contacts with the inflation control switch to open the air pressure control device, so that the air pressure control device inflates the air bag through the air passage connecting pipe.

Optionally, the first hydraulic chamber and the second hydraulic chamber are installed the other end of traction shaft, the one end of linkage subassembly is located the second hydraulic chamber, the other end of linkage subassembly is located in the sixth through-hole, the hold-down bar is located the one end of traction shaft, just the one end of hold-down bar is located in the sixth through-hole.

Optionally, a flange is provided at the other end of the pressing rod, and an outer diameter of the flange is larger than an inner diameter of the sixth through hole.

Optionally, the linkage assembly includes: the hydraulic slide block is positioned in the second hydraulic cavity, the hydraulic slide block is sealed in the second hydraulic cavity, the hydraulic slide block can slide along the axial direction of the traction shaft, the push rod is positioned in the sixth through hole, one end of the push rod is connected with the hydraulic slide block, the spring surrounds the push rod, and the spring compresses and stretches along the axial direction of the traction shaft.

Optionally, a spring is arranged between the hydraulic slider and the inner wall of the second hydraulic cavity, and the spring is compressed and stretched along the axial direction of the traction shaft.

Optionally, the other end of the push rod is fixedly connected with a sliding block, and thrust is applied to the pressing rod through the sliding block.

Optionally, one end of the traction shaft connected with the bell mouth is provided with two opposite first extending parts and second extending parts, the first extending parts and the second extending parts are respectively provided with a first through hole, the two first through holes are concentric, and the central connecting line of the two first through holes is perpendicular to the first axis of the traction shaft.

Optionally, the bell mouth can around the central line of first through-hole rotationally install in on the traction shaft, the binding off end with two extension of traction shaft are connected, be provided with a third through-hole on two terminal surfaces of binding off end respectively, two the third through-hole with first through-hole is concentric, wherein, first through-hole with the third through-hole is used for the intercommunication locking space with the accommodation space.

Optionally, a bearing assembly is further mounted at the other end of the traction shaft, the bearing assembly being located between the first hydraulic chamber and the drive mechanism.

Optionally, the bearing assembly includes a bearing seat, a first cushion pad and a second cushion pad, the first cushion pad, the bearing seat, the second cushion pad are provided with through holes for the traction shaft to pass through, the bearing seat is located between the first cushion pad and the second cushion pad, and the first cushion pad and the second cushion pad are in a precompressed state.

Optionally, a locking ring is further arranged between the first cushion pad and the bearing seat, and the locking ring is provided with a through hole for a traction shaft to pass through.

Optionally, a conical washer is further arranged between the second buffer pad and the locking assembly, and the conical washer is provided with a through hole for the traction shaft to pass through.

Optionally, the lock pin includes an arc portion and a cylindrical portion, the outer diameter of the arc portion is larger than the outer diameter of the cylindrical portion, wherein the lock pin enters the locking space and passes through the through hole of the traction ring, and when the traction ring is perpendicular to the axial direction of the lock pin, a minimum distance t1 between the outer wall of the arc portion and the inner wall of the traction ring is smaller than a distance t between the outer wall of the cylindrical portion and the inner wall of the traction ring.

According to yet another aspect of the present invention, there is also provided a traction device including: a towing hook as described above; and the traction ring is provided with a through hole for the lock pin of the traction hook to pass through so as to be connected with the traction hook.

Due to the use of the above technology, the invention has the following advantages compared with the prior art:

1) According to the invention, the pneumatic control component and the hydraulic compression component are added on the traction hook, so that when the traction hook is connected with the traction ring, the traction ring is compressed on the lock pin, a gap between the traction ring and the lock pin is eliminated, the running stability of the rear vehicle is improved, abnormal vibration is reduced, and the service life is prolonged;

2) According to the invention, the bearing assembly with two buffer pads is arranged at the other end of the traction shaft, so that a buffer effect is provided in the running process of the traction hook after being connected with an automobile, the mechanical damage of the bearing assembly and the traction shaft caused by collision in the running process is relieved, and the service life and the reliability of the traction hook are improved;

3) According to the invention, the shape of the lock pin is arranged, so that the gap between the lock pin and the inner wall of the through hole of the traction ring is relatively smaller, the impact force between the lock pin and the traction ring is reduced, and the contact area of the lock pin on the inner wall of the through hole of the traction ring can be further increased under the inclination angle of the traction ring, so that the traction hook can bear larger traction force, and the traction hook has longer service life.

Drawings

The technical scheme of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments so as to make the characteristics and advantages of the present invention more apparent.

FIG. 1 is a perspective view of a traction device according to an embodiment of the present invention;

FIG. 2 is an exploded view of a tow hook according to an embodiment of the present invention;

FIG. 3 is a perspective view of a traction axle according to an embodiment of the present invention;

FIG. 4 is a perspective view of a flare according to an embodiment of the present invention;

FIG. 5 is a perspective view of a drive mechanism according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of a tow hook attachment tow ring according to an embodiment of the invention;

FIG. 7 is a cross-sectional view of a tow hook attachment tow ring according to an embodiment of the invention;

FIG. 8 is a cross-sectional view of a tow hook unattached to a tow ring in accordance with one embodiment of the present invention;

FIG. 9 is an exploded view of a bearing assembly according to an embodiment of the present invention;

FIG. 10 is a schematic view of a bearing assembly according to an embodiment of the present invention;

FIG. 11 is a cross-sectional view of a bearing assembly according to an embodiment of the present invention;

FIG. 12 is a schematic view of a tow hook with a cylindrical locking pin according to an embodiment of the present invention;

FIG. 13 is a schematic view of a towing hook having an arcuate latch in accordance with an embodiment of the present invention;

fig. 14 is a schematic view of a tow hook with another state of an arcuate latch according to an embodiment of the present invention.

Reference numerals

1. The cylindrical portion of the traction shaft 42

11. First extension 5 bearing assembly

111. First through hole 51 bearing seat

12. Second extension 561 first cushion pad

121. First through hole 562 second cushion pad

13. First axis 57 locking ring

14. Another end 58 conical washer of the traction axle

15. Sixth through hole 201 air pressure control device

16. One end 202 inflation control switch of traction shaft

2. Horn 203 gas path connecting pipe

21. Open-end 204 balloon

22. First hydraulic cavity of closing end 301A

221. End face 301B second hydraulic chamber

222. Third through hole 302 linkage assembly

23. Locking space 302 hold down bar

3. Driving mechanism 304 hydraulic slide block

31. Driving mechanism shell 304A slider

311. Connecting plate for accommodating space 305

33. Handle 307 spring

331. Extension shaft 307A spring

34. Trigger plate 308 push rod

341. First end 309 of trigger plate is liquid

342. Second end 7 base assembly of trigger plate

35. Spring 9 traction ring

4. Through hole of lock pin 91

41. Arc-shaped part

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail. While the invention will be described and illustrated in conjunction with certain specific embodiments, it will be understood that it is not intended to limit the invention to these embodiments alone. On the contrary, the invention is intended to cover modifications and equivalent arrangements included within the scope of the appended claims.

In addition, numerous specific details are set forth in the following description in order to provide a better illustration of the invention. It will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known structures and components have not been described in detail in order to not obscure the present invention.

The structure of the towing apparatus and the towing hook according to an embodiment of the present invention will be described with reference to fig. 1 to 5. FIG. 1 is a perspective view of a traction device according to an embodiment of the present invention; FIG. 2 is an exploded view of a tow hook according to an embodiment of the present invention; FIG. 3 is a perspective view of a traction axle according to an embodiment of the present invention; FIG. 4 is a perspective view of a flare according to an embodiment of the present invention; fig. 5 is a perspective view of a driving mechanism according to an embodiment of the present invention.

As shown in fig. 1 to 5, the present invention provides a traction apparatus including a traction hook and a traction ring 9 having a through hole 91. The traction hook comprises a mechanical connecting component, an air pressure control component and a hydraulic pressing component. The mechanical connection assembly comprises a traction shaft 1, a bell mouth 2, a driving mechanism 3 and a lock pin 4.

The structure of the traction shaft 1 can be seen in fig. 3, wherein one end of the traction shaft 1 is provided with two opposite first and

second extensions

11, 12. The first extension 11 and the second extension 12 are provided with a first through

hole

111, 121, respectively. The two first through

holes

111, 121 are concentric, and the center line of the two first through

holes

111, 121 is perpendicular to the first axis 13 of the traction axle 1. The first axis 13 of the traction shaft 1 is the extension direction of the traction shaft 1.

The specific structure of the bell mouth 2 can be seen in fig. 4, and in combination with fig. 1 to 4, the bell mouth 2 is rotatably mounted on the traction shaft 1 about the central line of the first through

holes

111, 121. The flare 2 has an open end 21 and a closed end 22. The opening end 21 and the closing end 22 are communicated. The open end 21 has an opening size greater than the opening size of the closed end 22. The open end 21 is disposed away from the traction shaft 1, and the open end 21 is open away from the traction shaft 1. The closing end 22 is connected to the two

extensions

11, 12 of the traction shaft 1. The necked-in end 22 has two opposing end surfaces 221. Alternatively, the two opposite end surfaces 221 are connected to the two

extensions

11, 12 of the traction shaft 1 by means of a connection structure such as bolts. Optionally, the two opposite end surfaces 221 are located between the two

extensions

11, 12 of the traction axle 1. The two opposite end surfaces 221 are respectively provided with a third through hole 222. The two third through holes 222 are concentric with the first through

holes

111, 121, and a locking space 23 is formed between the two third through holes 222 (or the two opposite end faces 221).

The drive mechanism 3 is mounted on the first extension 11 of the traction shaft 1. The drive mechanism 3 has a drive device and a drive mechanism housing 31 accommodating the drive device. The driving mechanism housing 31 also forms an accommodating space 311. The receiving space 311 communicates with the locking space 23 of the flare 2 through the first through

holes

111, 121 and the third through hole 222. The driving means is used to control the movement of the locking pin 4 between the receiving space 31 and the locking space 23.

The drive mechanism 3 is also provided with a lever 37 for externally operating its internal drive means, which lever is used in cooperation with the control plate, the spring 35 and other parts of the drive means to control the locking pin movement. In some embodiments, the drive mechanism housing 31 is provided with attachment holes 38 for attachment means for adding an upgraded version of the accessory. The drive mechanism 3 may also be provided with an indicator 39 indicating the state of connection of the lock pin 4, and when the towing hook is in the open state, the lock pin 4 moves upward and pushes the indication rod in the indicator 39 to protrude outward, and it is clearly known from the outside that the lock pin 4 is in the open state. When the towing hook is in the closed condition (the lock pin 4 passes through and locks the towing ring 9), the indicating rod in the indicator 39 returns to the inside of the indicator 39, from the outside it is clear that the lock pin 4 has moved down to a specific position and locked the lock pin 4.

The mechanical connection assembly may further comprise a base assembly 7, wherein the base assembly 7 is configured to connect the bell mouth 2 with the second extension 12 of the traction shaft 1, and enable the bell mouth 2 to be reset to an initial state by rotating about the central line of the first through

holes

111, 121.

A towing hook provided with a pneumatic control assembly and a hydraulic hold down assembly according to an embodiment of the present invention is described below with reference to fig. 6 to 8. FIG. 6 is a cross-sectional view of a tow hook attachment tow ring according to an embodiment of the invention; FIG. 7 is a cross-sectional view of a tow hook attachment tow ring according to an embodiment of the invention; fig. 8 is a cross-sectional view of a tow hook unattached to a tow ring in accordance with one embodiment of the present invention.

The traction hook comprises a mechanical connecting component, an air pressure control component and a hydraulic pressing component. The mechanical connection assembly comprises a traction shaft 1, a bell mouth 2, a driving mechanism 3 and a lock pin 4. The drive means of the drive mechanism 3 comprise a handle 33 and a trigger plate 34. The handle 33 has an extension shaft portion 331, the extension shaft portion 331 passes through the first end 341 of the trigger plate 34, and the trigger plate 34 is rotatable with the extension shaft portion 331. The second end 342 of the trigger plate 34 abuts the lock pin 4. The handle 33 is rotated to drive the extension shaft 331 to rotate, the extension shaft 331 drives the trigger plate 34 to rotate, and the second end 342 of the trigger plate 34 controls the lock pin 4 to move up and down to be connected with the traction ring 9. The traction shaft 1 comprises one end 16 where the drive mechanism 3 is mounted and the other end 14 remote from the drive mechanism 3. The traction shaft 1 has a sixth through hole 15 penetrating the axial direction of the traction shaft 1.

The air pressure control assembly comprises an air pressure control device 201, an air inflation control switch 202, an air passage connecting pipe 203 and an air bag 204. The air pressure control device 201 and the inflation control switch 202 are mounted in the driving mechanism case 31 of the driving mechanism 3. An air bag 204 is mounted at the other end 14 of the traction shaft 1. The air passage connection pipe 203 is respectively connected with the air pressure control device 201 and the air bag 204. The inflation control switch 202 is used to control the air pressure control device 201.

The hydraulic compaction assembly includes a first hydraulic chamber 301A, a second hydraulic chamber 301B, a linkage assembly 302, and a compaction rod 303. The first hydraulic chamber 301A and the second hydraulic chamber 301B communicate and are mounted at the other end 14 of the traction shaft 1. Bladder 204 is located within first hydraulic chamber 301A. A liquid 309 is filled between the bladder 204 and the first hydraulic chamber 301A. One end of the linkage assembly 302 is located in the second hydraulic chamber 301B, and the other end of the linkage assembly 302 is located in the sixth through hole 15. The hold-down bar 309 is located at one end 16 of the traction shaft 1 and one end of the hold-down bar 303 is located within the sixth through hole 15. The other end of the pressing rod 303 may be provided with a flange having an outer diameter larger than the inner diameter of the sixth through hole 15, the flange being provided such that the pressing rod 303 is not completely located in the sixth through hole 15 during movement.

When the handle 33 is rotated to rotate the trigger plate 34 to control the lock pin 4 to pass through the through hole 91 of the traction ring 9, the trigger plate 34 contacts the inflation control switch 202, and the air pressure control device 201 is opened to inflate the air bag 204 through the air passage connection tube 203 by the air pressure control device 201. The volume of the air bag 204 is increased, so that the liquid 309 in the first hydraulic cavity 301A flows to the second hydraulic cavity 301B, the second hydraulic cavity 301B pushes the linkage assembly 302 to push the compression rod 303 to one end 16 of the traction shaft 1, so that the compression rod 303 abuts against the end of the traction ring 9, and a gap between the inner wall of the through hole 91 of the traction ring 9 and the outer wall of the lock pin 4 is reduced. When the lock pin 4 moves up from the through hole 91 of the traction ring 9, the air pressure control device 201 reduces the air pressure in the air bag 204 connected with the air passage connection pipe 203, the air bag 204 reduces in volume, so that the liquid 39 in the second hydraulic cavity 301B flows to the first hydraulic cavity 301A, the pressure in the second hydraulic cavity 301B is reduced, the linkage assembly 302 moves towards the other end 14 of the traction shaft 1, the compression rod 303 is not abutted against the end of the traction ring 9, and the compression force is not applied to the inner wall of the through hole 91 of the traction ring 9 and the lock pin 4. Specifically, the linkage assembly 302 may include a hydraulic ram 304, a spring 307, and a push rod 308.

The hydraulic slider 304 is located in the second hydraulic chamber 301B. The hydraulic slider 304 seals the second hydraulic chamber 301B, and the hydraulic slider 304 is slidable in the axial direction of the traction shaft 1. When the liquid 309 in the first hydraulic chamber 301A flows toward the second hydraulic chamber 301B, the hydraulic slider 304 is pushed to slide toward the drive mechanism 3. When the liquid 309 in the second hydraulic chamber 301B flows toward the first hydraulic chamber 301A, the hydraulic slider 304 slides away from the drive mechanism 3. Optionally, a spring 307A is provided between the hydraulic slider 304 and the inner wall of the second hydraulic chamber 301B. The spring 307A is compressed and stretched in the axial direction of the traction shaft 1 to elastically slide the hydraulic slider 304 with respect to the inner wall of the second hydraulic chamber 301B.

The push rod 308 is located in the sixth through hole 15, and one end of the push rod 308 is connected to the hydraulic slider 304. Optionally, the push rod 308 is fixedly connected to the hydraulic slide 304 via a connecting plate 305. Alternatively, the other end of the push rod 308 is fixedly connected to a slider 304A, and thrust is applied to the pressing rod 309 by the slider 304A. A spring 307 may also be provided between the push rod 308 and the inner wall of the sixth through hole 15 at a position between the connection plate 305 and the slider 304A.

As the hydraulic slide 304 slides towards the drive mechanism 3, the spring 307 compresses and the push rod 308 also slides with the hydraulic slide 304 towards the drive mechanism 3 until the hold-down rod 309 is pushed against the end of the traction ring 9. When the traction ring 9 is unhooked, because the pressure in the second hydraulic chamber 301B is reduced, when the hydraulic slider 304 slides back to the driving mechanism 3, the push rod 308 moves back to the driving mechanism 3 under the action of the spring 307, the slider 304A also moves to the other end 14 of the traction shaft 1 under the action of the spring, the pressing rod 303 is spaced from the traction ring 9 by a certain distance, and the traction ring 9 is disengaged. According to the invention, the pneumatic control component and the hydraulic compression component are added on the traction hook, so that when the traction hook is connected with the traction ring 9, the traction ring 9 is compressed on the lock pin 4, the gap between the inner wall of the through hole 91 of the traction ring 9 and the outer wall of the lock pin 4 is reduced or eliminated, the running stability of a rear car is improved, abnormal vibration is reduced, and the service lives of the traction hook and the traction ring 9 are prolonged.

The bearing assembly 5 according to an embodiment of the present invention is described below with reference to fig. 9 to 11. FIG. 9 is an exploded view of a bearing assembly 5 according to an embodiment of the present invention; FIG. 10 is a schematic view of a bearing assembly 5 according to an embodiment of the invention; fig. 11 is a cross-sectional view of a bearing assembly 5 according to an embodiment of the invention.

One end of the traction shaft 1 is provided with a bell mouth 2 and a driving mechanism 3, and the other end 14 of the traction shaft 1 is provided with a bearing assembly 5. A bearing assembly 5 is located between the first hydraulic chamber 301A and the drive mechanism 3.

The bearing assembly 5 includes a bearing housing 51, a first cushion 561, a second cushion 562. The bearing housing 51 is used to connect the towing axle 1 and the trailer. The first cushion 561 and the second cushion 562 may be both rubber cushions, and the first cushion 561 and the second cushion 562 may be the same in size and elastic coefficient.

The first cushion 561, the bearing housing 51, and the second cushion 562 have through holes for the traction shaft 1 to pass through. Specifically, the first cushion pad 561, the bearing housing 51, and the second cushion pad 562 sequentially pass through the traction shaft 1 from the other end 14 of the traction shaft 1. The bearing housing 51 is located between the first cushion 561 and the second cushion 562. The first cushion 561 and the second cushion 562 are in a pre-compressed state.

Optionally, a locking ring 57 is further provided between the first cushion pad 561 and the bearing housing 51, and the locking ring 57 has a through hole for the traction shaft 1 to pass through. The locking ring 57 serves to prevent the first cushion 561 from moving axially away from the bell mouth 2 and to maintain it in a pre-compressed state.

Optionally, a tapered washer (e.g., tapered cap 58) is also provided between the second bumper 562 and the locking assembly, the tapered washer 58 having a through hole therein for the traction axle 1 to pass through. The tapered washer 58 acts to resist movement of the second bumper 562 axially away from the flare 2 and maintains it in a pre-compressed state.

In this embodiment, through installing the bearing assembly 5 that has two blotters at the other end 14 of traction shaft 1, and then in the driving process after the connection of towing hook and car, two blotters mutually support, provide the cushioning effect, alleviate the mechanical damage that bearing assembly 5 and traction shaft 1 lead to because the striking in the driving process, improve the life and the reliability of towing hook. Meanwhile, in the present embodiment, the two cushioning pads are maintained in a pre-compressed state by the locking ring 57 and the tapered washer 58, further improving the cushioning effect.

A lock pin according to an embodiment of the present invention is described below with reference to fig. 12 to 14. FIG. 12 is a schematic view of a tow hook with a cylindrical locking pin according to an embodiment of the present invention; FIG. 13 is a schematic view of a towing hook having an arcuate latch in accordance with an embodiment of the present invention; fig. 14 is a schematic view of a tow hook with another state of an arcuate latch according to an embodiment of the present invention.

See first fig. 13 and 14. The traction hook comprises a traction shaft 1, a bell mouth 2, a driving mechanism 3 and a lock pin 4. The traction shaft 1 is connected to the flare 2, and the flare 2 has a locking space 23. After the traction ring 9 enters the locking space 23, the driving mechanism 3 controls the locking pin 4 to enter the locking space 23 and pass through the through hole 91 of the traction ring 9.

The locking pin 4 includes a first portion (e.g., arcuate portion 41) and a second portion (e.g., cylindrical portion 42), the first portion 41 having an outer diameter greater than the outer diameter of the second portion 42. When the lock pin 4 enters the lock space 23 and passes through the through hole 91 of the traction ring 9, and the traction ring 9 is perpendicular to the axial direction (or moving direction) of the lock pin 4, the minimum distance t1 between the outer wall of the first portion 41 and the inner wall of the through hole 91 of the traction ring 9 is smaller than the distance t between the outer wall of the second portion 42 and the inner wall of the through hole 91 of the traction ring 9. Optionally, the axial height of the first portion 41 is equal to the axial height of the traction ring 9.

In contrast to the cylindrical locking pin 4 shown in fig. 12, when the cylindrical locking pin 4 passes through the through hole 91 of the traction ring 9, the clearance between the cylindrical locking pin 4 and the inner wall of the through hole 91 of the traction ring 9 is large, and during use, large impact force is generated between the traction ring 9 and the locking pin 4 due to the existence of the clearance and the change of the vehicle speed. While the arc-shaped portion 41 of the lock pin 4 shown in fig. 13 and 14 has a relatively small clearance with the inner wall of the through hole 91 of the traction ring 9, the impact force between the lock pin 4 and the traction ring 9 can be reduced.

Further in contrast to the cylindrical locking pin 4 shown in fig. 12, with a generally cylindrical locking pin, in the inclined state as shown in fig. 12 and 14, the contact between the traction ring 9 and the locking pin 4 is linear, the contact area is small, the contact point is subjected to a large force, the locking pin 4 is easily damaged at the contact point, and the service life is short. In the inclined state as shown in fig. 12 and 14, the arc-shaped portion 41 of the lock pin 4 shown in fig. 13 and 14 can keep good contact with the inner wall of the through hole 91 of the traction ring 9, has a larger contact surface, can bear larger traction force, and enables the lock pin 4 and the traction ring 9 to have longer service life.

The foregoing is merely a specific application example of the present invention, and the protection scope of the present invention is not limited in any way. In addition to the embodiments described above, other embodiments of the invention are possible. All technical schemes formed by equivalent substitution or equivalent transformation fall within the scope of the invention.

Claims

1. A towing hitch, characterized in that it passes through a towing loop (9) with a through hole (91) by means of a locking pin (4) to connect with the towing loop (9), the towing hitch comprising:

the mechanical connecting assembly comprises a traction shaft (1), a horn mouth (2), a driving mechanism (3) and a lock pin (4), wherein the driving mechanism (3) controls the lock pin (4) to move up and down so as to be connected with and disconnected from the traction ring (9);

the air pressure control assembly comprises an air pressure control device (201), an air passage connecting pipe (203) and an air bag (204), wherein the air pressure control device (201) is arranged at one end of the mechanical connecting assembly, which is provided with the lock pin (4), the air bag (204) is arranged at the other end of the mechanical connecting assembly, and the air passage connecting pipe (203) is respectively connected with the air pressure control device (201) and the air bag (204);

the hydraulic compaction assembly comprises a first hydraulic cavity (301A), a second hydraulic cavity (301B), a linkage assembly (302) and a compaction rod (303), wherein the first hydraulic cavity (301A) is communicated with the second hydraulic cavity (301B) and is arranged at the other end of the mechanical connection assembly, the air bag (204) is positioned in the first hydraulic cavity (301A), liquid (309) is filled between the air bag (204) and the first hydraulic cavity (301A), one end of the linkage assembly (302) is connected with the second hydraulic cavity (301B), the other end of the linkage assembly (302) is opposite to one end of the compaction rod (303),

when the lock pin (4) passes through the through hole (91) of the traction ring (9), the air pressure control device (201) inflates the air bag (204) through the air passage connecting pipe (203), the volume of the air bag (204) is increased, so that liquid (309) in the first hydraulic cavity (301A) flows to the second hydraulic cavity (301B), the linkage assembly (302) pushes the compression rod (303) to one end of the mechanical connection assembly, and the compression rod (303) abuts against the end of the traction ring (9):

when the lock pin (4) is moved out of the through hole (91) of the traction ring (9), the air pressure control device (201) reduces the air pressure in the air bag (204) connected with the air passage connecting pipe (203), the air bag (204) reduces in volume so that liquid (309) in the second hydraulic cavity (301B) flows to the first hydraulic cavity (301A), the pressure in the second hydraulic cavity (301B) is reduced, the linkage assembly (302) moves away from one end of the mechanical connection assembly, and the pressing rod (303) is not abutted against the end of the traction ring (9).

2. A towing hook as claimed in claim 1, characterized in that the towing shaft (1) has a sixth through-hole (15) extending through the towing shaft (1) in the axial direction; the horn mouth (2) is provided with an opening end (21) and a closing end (22), the opening size of the opening end (21) is larger than that of the closing end (22), the closing end (22) is connected with one end (16) of the traction shaft (1), the closing end (22) is provided with two opposite end surfaces (221), a locking space (23) is formed between the two opposite end surfaces (221), and the opening end (21) is arranged opposite to the traction shaft (1); the driving mechanism (3) is provided with a driving device and a driving mechanism shell (31) for accommodating the driving device, the driving mechanism shell (31) forms a containing space (311) communicated with the locking space (23), and the driving device controls the lock pin (4) to move between the containing space (311) and the locking space (23).

3. A towing hook as claimed in claim 2, characterized in that the drive mechanism (3) is mounted at one end (16) of the towing axle (1), the drive means comprising:

a handle (33) and a trigger plate (34) in the driving mechanism housing (31), wherein the handle (33) is provided with an extension shaft part (331), the extension shaft part (331) passes through a first end (341) of the trigger plate (34), the trigger plate (34) rotates along with the extension shaft part (331), a second end (342) of the trigger plate (34) abuts against the lock pin (4),

the handle (33) is rotated to drive the extension shaft (331) to rotate, the extension shaft (331) drives the trigger plate (34) to rotate, and the second end (342) of the trigger plate (34) controls the lock pin (4) to move up and down to be connected with and disconnected from the traction ring (9).

4. A towing hook as claimed in claim 3, characterized in that the pneumatic control means (201) are mounted in a drive mechanism housing (31) of the drive mechanism (3), the air bag (204) being mounted at the other end (14) of the towing axle (1).

5. The hitch of claim 4, wherein said air pressure control assembly further comprises:

an inflation control switch (202) for controlling the air pressure control device (201) installed in a driving mechanism housing (31) of the driving mechanism (3),

wherein when the handle (33) is rotated to rotate the trigger plate (34) to control the lock pin (4) to pass through the through hole (91) of the traction ring (9), the trigger plate (34) contacts the inflation control switch (202) to open the air pressure control device (201), so that the air pressure control device (201) inflates the air bag (204) through the air passage connecting pipe (203).

6. A towing hook according to claim 3, characterized in that the first hydraulic chamber (301A) and the second hydraulic chamber (301B) are mounted at the other end (14) of the towing axle (1),

one end of the linkage assembly (302) is positioned in the second hydraulic cavity (301B), the other end of the linkage assembly (302) is positioned in the sixth through hole (15),

the pressing rod (303) is located at one end (16) of the traction shaft (1), and one end of the pressing rod (303) is located in the sixth through hole (15).

7. The towing hook as claimed in claim 6, characterized in that the other end of the hold-down lever (303) is provided with a flange, the outer diameter of which flange is larger than the inner diameter of the sixth through hole (15).

8. The hitch of claim 2, in which the linkage assembly (302) includes:

a hydraulic slide block (304), a spring (307) and a push rod (308),

the hydraulic slide block (304) is positioned in the second hydraulic cavity (301B), the hydraulic slide block (304) seals the second hydraulic cavity (301B), the hydraulic slide block (304) slides along the axial direction of the traction shaft (1),

the push rod (308) is positioned in the sixth through hole (15), one end of the push rod (308) is connected with the hydraulic slide block (304),

the spring (307) surrounds the push rod (308), and the spring (307) is compressed and stretched in the axial direction of the traction shaft (1).

9. The towing hook according to claim 8, characterized in that a spring (307A) is arranged between the hydraulic slide (304) and the inner wall of the second hydraulic chamber (301B), which spring (307A) is compressed and stretched in the axial direction of the towing shaft (1).

10. The towing hook as claimed in claim 9, characterized in that the other end of the push rod (308) is fixedly connected to a slide (304A) and is arranged to exert a pushing force on the hold-down lever (303) via the slide (304A).

11. A towing hook as claimed in claim 2, characterized in that the end (16) of the towing axle (1) connected to the bell mouth (2) is provided with two opposite first extensions (11) and second extensions (12), the first extensions (11) and the second extensions (12) being provided with a first through-hole (111, 121) respectively, the two first through-holes (111, 121) being concentric, and the centre line of the two first through-holes (111, 121) being perpendicular to the first axis (13) of the towing axle (1).

12. Towing hook according to claim 11, characterized in that the bell mouth (2) is rotatably mounted on the towing axle (1) about the centre line of the first through-hole (111, 121), the closing end (22) being connected to two extensions (11, 12) of the towing axle (1), the closing end (22) being provided with a third through-hole (222) on each of the two end faces (221) of the closing end (22), the two third through-holes (222) being concentric with the first through-hole (111, 121),

wherein the first through hole (111, 121) and the third through hole (222) are used for communicating the locking space (23) and the accommodating space (311).

13. A towing hook as claimed in claim 2, characterized in that the other end (14) of the towing axle (1) is also fitted with a bearing assembly (5), which bearing assembly (5) is located between the first hydraulic chamber (301A) and the drive mechanism (3).

14. The hitch of claim 13, in which the bearing assembly (5) includes a bearing housing (51), a first cushion pad (561) and a second cushion pad (562),

the first cushion pad (561), the bearing seat (51) and the second cushion pad (562) are provided with through holes for the traction shaft (1) to pass through, the bearing seat (51) is positioned between the first cushion pad (561) and the second cushion pad (562), and the first cushion pad (561) and the second cushion pad (562) are in a precompressed state.

15. The towing hook according to claim 14, characterized in that a locking ring (57) is further arranged between the first cushion pad (561) and the bearing block (51), the locking ring (57) having a through hole for the towing axle (1) to pass through.

16. The towing hook as claimed in claim 14, characterized in that a conical washer (58) is further arranged between the second bumper (562) and the locking assembly, the conical washer (58) having a through hole for the towing shaft (1) to pass through.

17. The hitch of any one of claims 1 to 16,

the lock pin (4) comprises an arc-shaped part (41) and a cylindrical part (42), wherein the outer diameter of the arc-shaped part (41) is larger than the outer diameter of the cylindrical part (42),

the lock pin (4) enters the locking space (23) and passes through the through hole (91) of the traction ring (9), and when the traction ring (9) is perpendicular to the axial direction of the lock pin (4), the minimum distance t1 between the outer wall of the arc-shaped part (41) and the inner wall of the through hole (91) of the traction ring (9) is smaller than the distance t between the outer wall of the cylindrical part (42) and the inner wall of the through hole (91) of the traction ring (9).

18. A traction device, comprising:

the tow hook of any one of claims 1 to 17; and

a traction ring (9) having a through hole (91) for the passage of the locking pin (4) of the traction hook to connect with the traction hook.