CN212071779U

CN212071779U - Pin pulling device

Info

Publication number: CN212071779U
Application number: CN202020831618.3U
Authority: CN
Inventors: 李利斌; 张扬; 江振阳; 于利民; 马辰飞; 宫庆波
Original assignee: Sany America Inc
Current assignee: SHANDONG HAIWAN HOISTING ENGINEERING Co.,Ltd.; Sany America Inc
Priority date: 2020-05-18
Filing date: 2020-05-18
Publication date: 2020-12-04
Anticipated expiration: 2030-05-18

Abstract

The utility model provides a pin pulling device relates to engineering machine tool technical field, is applied to the hoist, include: the transmission rod is matched with the rack; the rack is used for being connected with an arm support of a crane, one end of the transmission rod is rotatably connected with the rack, the other end of the transmission rod is in transmission connection with the fitting piece, and the fitting piece is used for being connected with a pin shaft at the joint of the crane arm section and is used for driving the fitting piece to move axially along the transmission rod to drive the pin shaft to be separated from the joint of the crane arm section when the transmission rod is driven to rotate around the axis of the transmission rod by external force relative to. The pin shaft is driven to be separated from the connecting part of the crane arm joint along with the movement of the matching piece, so that the pin pulling function is realized. The pin pulling device with the structure can realize the pin pulling function only by a small volume by utilizing a pure mechanical transmission mode, and meanwhile, the reliability is high, so that the condition that the hydraulic pin pulling fails due to the damage of the hydraulic device is avoided.

Description

Pin pulling device

Technical Field

The utility model relates to an engineering machine tool technical field particularly, relates to a pull out round pin device.

Background

With the rapid development of economy, the living standard of people is remarkably improved, and higher requirements are made on the completeness of infrastructure construction. The crane is an important device widely applied in infrastructure construction and mainly responsible for the lifting work of heavy objects, and the crane telescopic mechanism realizes the telescopic function of a telescopic crane boom (for short, an extension boom) through the combined action of a telescopic oil cylinder, a boom pin and a cylinder pin.

In the crane arm extending process, adjacent arm sections are connected by using pin shafts, and when necessary, the pin pulling device is used for completing the operation of pulling out the pin shafts of different arm sections. The existing pin pulling device generally adopts a pin pulling oil cylinder, namely, a crane is provided with the pin pulling oil cylinder, and meanwhile, the pin pulling oil cylinder is also provided with a power source, namely a hydraulic pump station. Because hydraulic power unit's volume is comparatively huge, and need place near the pull pin hydro-cylinder all the time, when the pull pin hydro-cylinder carries out the operation to different armlet, need frequently move hydraulic power unit, lead to the operating efficiency lower.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to the not enough among the above-mentioned prior art, provide a pull out round pin device to because of the great lower problem of operating efficiency that leads to of volume when solving the operation of current fluid pressure type pull out round pin device.

In order to achieve the above object, the embodiment of the present invention adopts the following technical solutions:

the utility model discloses an aspect provides a pulling pin device is applied to the hoist, include: the transmission rod is matched with the rack; the rack is used for being connected with an arm support of the crane, one end of the transmission rod is rotatably connected with the rack, the other end of the transmission rod is in transmission connection with the fitting piece, the fitting piece is used for being connected with a pin shaft at the joint of the crane arm joint, the transmission rod rotates around the axis of the transmission rod, and the fitting piece is driven to move axially along the transmission rod so as to drive the pin shaft to be separated from the joint of the crane arm joint.

Optionally, a through hole is formed in the fitting piece, and the fitting piece is sleeved on the periphery of the transmission rod through the through hole.

Optionally, the outer circumference of the transmission rod and the inner circumference of the through hole of the mating member are respectively provided with a single thread which is matched with each other.

Optionally, the transmission rod is a reciprocating screw rod, and a protrusion matched with a thread groove of the reciprocating screw rod is arranged on the inner periphery of the through hole of the matching piece.

Optionally, a bearing is arranged at the end of the transmission rod, and the end of the transmission rod is rotatably connected with the frame through the bearing.

Optionally, the fitting comprises a fitting body fitted with the transmission rod and a locking member disposed on the fitting body, and the fitting body can be locked or unlocked with the pin shaft through the locking member.

Optionally, the transmission rods comprise a plurality of transmission rods which are arranged in parallel, one ends of the transmission rods are respectively connected with the rack in a rotating mode, and the other ends of the transmission rods are respectively connected with the matching piece in a transmission mode.

Optionally, the pin pulling device further comprises a driving portion, the driving portion is rotatably connected with the rack, the plurality of transmission rods are arranged with the rotation center ends of the driving portion and the rack as the center, and the rotation center ends of the driving portion are respectively in transmission connection with the plurality of transmission rods.

Optionally, one end of each of the plurality of transmission rods close to the rack is further provided with a first gear part, the driving part is provided with a second gear part, and the second gear part is located at a rotation center of the driving part and the rack and is meshed with the first gear part.

Optionally, the diameter of the second gear part is smaller than the diameter of the first gear part.

The beneficial effects of the utility model include:

the utility model provides a pin pulling device is applied to the hoist, include: frame, transfer line and fitting piece. Wherein, the fitting piece is matched with the transmission rod for transmission. The frame is connected with the arm support of the crane, so that the arm support of the crane is utilized to limit the frame along the axial direction of the transmission rod. And connecting the matching piece with a pin shaft at the connecting part of the arm joint of the crane. One end of the transmission rod is rotatably connected with the rack, and the other end of the transmission rod is matched with the matching piece. When the crane jib joint pulling device is used, external force is applied to the transmission rod, the transmission rod rotates relative to the rack under the driving of the external force, the rack is limited along the axial direction of the transmission rod due to the fact that the arm support is limited to the rack, and similarly, the rack is limited along the axial direction of the transmission rod due to the fact that the transmission rod is limited by the rack. The pin pulling device with the structure can realize the pin pulling function only by a small volume by utilizing a pure mechanical transmission mode, and meanwhile, the reliability is high, so that the condition that the hydraulic pin pulling fails due to the damage of the hydraulic device is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a pin pulling apparatus according to an embodiment of the present invention;

fig. 2 is a second schematic structural view of a pin pulling apparatus according to an embodiment of the present invention;

fig. 3 is a third schematic structural diagram of a pin pulling apparatus according to an embodiment of the present invention.

Icon: 100-arm joint connection; 101-a pin shaft; 102-arm segment; 103-arm support; 200-a frame; 300-a transmission rod; 310-a first gear portion; 320-a bearing; 330-thread groove; 400-a mating member; 410-fitting body; 420-a locking member; 500-a drive section; 510-second gear part.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. It should be noted that, in the case of no conflict, various features in the embodiments of the present invention may be combined with each other, and the combined embodiments are still within the scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

With the increase of the tonnage of the crane, a bolt form is adopted, namely a pin shaft (called as a boom pin because of being arranged on the boom) which can lock the boom and the boom outside the boom together and can move up and down is arranged above the tail end of each boom section, the boom pin is used for realizing the locking (fixed connection) and unlocking between the boom and the boom, the initial position of the boom pin can move up to the boom hole of the other boom under the action of a spring force, so that the boom and the boom cannot move mutually to achieve the effect of fixed connection, when the boom pin retracts from the boom hole under the action of a boom pin oil cylinder on a telescopic oil cylinder, the boom and the boom can move mutually under the unlocking state, and the aim of unlocking is achieved. When the existing crane arm joint needs to be unlocked, the hydraulic driving pin pulling oil cylinder is mainly used for providing driving force, namely, one crane is provided with one pin pulling oil cylinder, and meanwhile, a hydraulic pump station is required to be provided for the power source for ensuring the pin pulling oil cylinder. Because the volume of hydraulic power unit is comparatively huge, and need place near the pull pin hydro-cylinder all the time, when the pull pin hydro-cylinder carries out the operation to different arm sections, need frequently to move hydraulic power unit. Not only the low operating efficiency is caused, but also the later maintenance of the hydraulic system consisting of the pin pulling oil cylinder and the hydraulic pump station is more complicated. Based on the basis, the application provides a pin pulling device, and the problems are solved.

The utility model discloses an aspect, refer to fig. 1, provide a pulling pin device, be applied to the hoist, include: a frame 200, a transmission rod 300 and a fitting part 400 matched with the transmission rod 300; the rack 200 is used for being connected with the arm support 103 of the crane, one end of the transmission rod 300 is rotatably connected with the rack 200, the other end of the transmission rod is in transmission connection with the fitting piece 400, the fitting piece 400 is used for being connected with the pin shaft 101 of the crane arm joint 100, the transmission rod 300 rotates around the axis of the transmission rod 300, and the fitting piece 400 is driven to move along the axial direction of the transmission rod 300 so as to drive the pin shaft 101 to be separated from the crane arm joint 100.

Illustratively, a pin pulling device is provided, which comprises a frame 200, a transmission rod 300 and a fitting piece 400. As shown in fig. 1, the frame 200 is connected to the boom 103 of the crane to form a first limit position of the pin pulling device, wherein the connection mode may be a connection mode through a bolt as shown in fig. 1, or a connection mode through a buckle or a bolt, so as to limit the axial movement of the frame along the transmission rod 300 after the connection, and in order to achieve a more stable connection, as shown in fig. 1, two opposite sides of the frame 200 may be connected to the boom 103 of the crane. One end of the transmission rod 300 is disposed on the frame 200 and is rotatably connected to the frame 200, for example, as shown in fig. 1, and the end of the transmission rod 300 is rotatably connected to the frame 200, so that the transmission rod 300 can rotate around its axis direction with respect to the frame 200 but cannot move in its axis direction with respect to the frame 200. At the other end of the transmission rod 300, a fitting 400 is provided, wherein the fitting 400 can be in fit transmission with the transmission rod 300 so as to drive the fitting 400 to move along the axial direction of the transmission rod 300 when the transmission rod 300 rotates relative to the frame 200. Meanwhile, the fitting piece 400 is connected with the pin 101 of the arm section connecting part 100 of the crane to form a second limiting part of the pin pulling device, and the specific connection form may be a bolt, a screw, a buckle, a clamp, and the like, which is not specifically limited in this embodiment. That is, the pin pulling device has two position-limiting positions, and since the entire structure of the crane arm frame 103 and the crane is rigid, and the pin shaft 101 of the crane arm joint 100 is inserted into the position-limiting positions, when the transmission rod 300 rotates around its axis direction relative to the frame 200, the frame 200 disposed at the end of the transmission rod 300 does not move relative to the crane arm frame 103 along the axis direction of the transmission rod 300. At this time, the fitting piece 400 and the transmission rod 300 are in transmission connection, so the fitting piece 400 will move along the axial direction of the transmission rod 300, and then the pin 101 connected with the fitting piece 400 is driven to be separated from the pin 101 hole of the crane jib joint 100.

In practice, the frame 200 is connected to the boom 103 of the crane, after which the fitting piece 400 is connected to the end of the pin 101. When the transmission rod 300 is driven to rotate around the axis direction by an external force, the rack 200 limits the transmission rod 300 to be incapable of moving in the axis direction, and based on the transmission connection relationship between the transmission rod 300 and the fitting piece 400, the fitting piece 400 moves the relative transmission rod 300 along the axis direction, so that the pin shaft 101 is driven to be separated from the pin shaft 101 hole of the crane jib joint connection part 100, and the unlocking operation of the adjacent crane jib joint 102 is completed. It should be noted that, the pin pulling device of this application not only can realize the pin pulling function, can also realize the bolt function, concrete use is for fixedly setting up round pin axle 101 on fitting piece 400, and guarantee that a tip of round pin axle 101 corresponds with the round pin axle 101 hole of hoist arm festival junction 100, along with the rotation of transfer line 300 drives fitting piece 400 and is close to the arm festival junction 100 of hoist gradually, along with the rotation that transfer line 300 lasts, make the other end of round pin axle 101 insert the round pin axle 101 hole of the arm festival junction 100 of hoist gradually, and then accomplish the bolt operation.

Through foretell pulling pin device, can carry out the plug operation to the round pin axle 101 of crane jib festival junction 100 based on the transmission mode of pure machinery, it is higher to compare hydraulic control's pulling pin device reliability, can not lead to pulling pin failure because of hydraulic power unit trouble or the pollution of hydraulic oil. Meanwhile, the structure is small and exquisite, the operation and the control are easy, when an operator inserts and extracts the pin shaft 101 at the connecting part 100 of different arm sections of the crane, the operation can be realized in a more convenient and quick mode, and the operation efficiency is effectively improved.

First, the pin pulling device can not only realize the pin pulling, but also realize the pin plugging, and in understanding, the actual function of the pin pulling device should not be limited by its name.

Secondly, the arm support 103 of the crane is a rigid rod welded on the arm sections 102 of the crane, and may be respectively disposed at two ends of each arm section 102 of the crane, that is, disposed near the joint of adjacent arm sections 102, as required.

Thirdly, the above-mentioned crane jib connection 100 refers to the position where the pin 101 is inserted into the crane jib 102.

Fourthly, the external force driving may be that an operator manually rotates the transmission rod 300 (for convenience of operation, a crank handle may be disposed at an end of the transmission rod 300 close to the rack 200 as shown in fig. 2), or an electric wrench may be used to cooperate with an end of the transmission rod 300 close to the rack 200, and the electric wrench is driven to rotate in a motor driving manner, so as to insert and extract the pin shaft 101.

Optionally, a through hole is formed in the fitting member 400, and the fitting member 400 is sleeved on the periphery of the transmission rod 300 through the through hole.

For example, as shown in fig. 2, a through hole is formed in the fitting piece 400, and the fitting piece 400 is sleeved on the periphery of the transmission rod 300 through the through hole, so that when the transmission rod 300 drives the fitting piece 400 to move, the fitting piece 400 can be better limited in the radial direction of the transmission rod 300, the transmission strength of the fitting piece 400 and the transmission rod 300 can be improved, and the pin shaft 101 can be smoothly inserted and pulled out. When the fitting member 400 is fitted around the outer periphery of the transmission rod 300, the transmission forms of the fitting member and the transmission rod can be various, and two of them will be schematically illustrated below.

Alternatively, single threads that are engaged with each other are provided on the outer circumference of the driving lever 300 and the inner circumference of the through-hole of the engaging member 400, respectively.

As shown in fig. 2, one of them may be a single-handed external thread provided on the outer circumference of the driving rod 300, and an internal thread provided on the inner wall of the through hole of the fitting 400 to be fitted with the external thread. When the external force drives the transmission rod 300 to rotate, the external force drives the transmission rod 300 and the transmission rod to drive the matching piece 400 to move along the axis direction of the transmission rod 300 in a threaded transmission mode, and therefore the matching piece can move towards the direction close to the crane arm joint 100 or the direction far away from the crane arm joint 100, and selection can be carried out according to actual plugging and unplugging requirements. For example, when the drive link 300 is rotated in a counterclockwise direction, the engagement member 400 may be driven away from the crane jib articulation joint 100, which is a pin removal operation. The control of the transmission rod 300 to rotate in a clockwise direction drives the mating member 400 to move towards the position close to the crane jib joint connection 100, thereby realizing the latch operation. The form of the threaded connection transmission is mature in process and low in manufacturing cost, transmission strength can be effectively guaranteed, and the service durability of the pin pulling device is improved.

Alternatively, the driving rod 300 is a reciprocating screw, and a protrusion engaged with the thread groove 330 of the reciprocating screw is provided on the inner circumference of the through hole of the engaging member 400.

Illustratively, as shown in fig. 3, the transmission rod 300 is a reciprocating screw, and a protrusion is provided on an inner wall of the through hole of the fitting 400, and the protrusion can be received in a thread groove 330 provided on an outer circumferential wall of the transmission rod 300 when the fitting 400 is fitted around an outer circumference of the reciprocating screw. When the transmission rod 300 is driven to rotate along its own axis by an external force, the transmission rod 300 guides the axial movement of the protrusion along the transmission rod 300 through the thread groove 330 formed on the outer peripheral wall thereof, i.e., the protrusion is applied with a component force along the axial direction of the transmission rod 300 by the groove wall of the thread groove 330, so as to drive the mating member 400 to move along the axial direction of the transmission rod 300. In addition, in order to enable the fitting piece 400 to have better stability in the movement process, a smooth rod parallel to the transmission rod 300 can be further arranged on the rack 200, so that the fitting piece 400 is sleeved on the periphery of the smooth rod, the fitting piece 400 can provide a force to the pin shaft 101 along the axial direction of the transmission rod 300, and the phenomenon that the pin shaft 101 is tightly abutted to the inner wall of the hole of the pin shaft 101 due to component force to cause difficulty in plugging and unplugging is avoided. The reciprocating screw rod can apply a driving force to the driving rod 300 in only one direction, so that the insertion and extraction operation can be completed. The working efficiency is further improved.

Optionally, a bearing 320 is disposed at an end of the transmission rod 300, and the end of the transmission rod 300 is rotatably connected to the frame 200 through the bearing 320.

Illustratively, as shown in fig. 2, in order to improve the stability of the connection between the driving rod 300 and the frame 200 and reduce the wear of the driving rod 300 caused by the rotation of the driving rod 300 relative to the frame 200, a bearing 320 may be further provided at the end of the driving rod 300, so that the driving rod 300 is rotatably connected to the frame 200 through the bearing 320. In order to improve the stability of the connection between the transmission rod 300 and the frame 200, as shown in fig. 2, two bearings 320 may be further disposed at the end of the same transmission rod 300, so as to further improve the stability of the connection between the two.

Optionally, the engaging member 400 includes an engaging body engaged with the transmission rod 300 and a locking member 420 provided on the engaging body, and the engaging body can be locked or unlocked with the pin 101 by the locking member 420.

For example, as shown in fig. 2, the fitting member 400 may further include a fitting member body 410 and a locking member 420 disposed on the fitting member body 410, and when the pin is pulled out or inserted, it is first required to lock an end of the pin 101 with the fitting member 400 through the locking member 420, so that the two can form a stable connection relationship. After the locking member 420 locks the pin 101 and the mating member 400, the locking member can be removed when it is not needed, that is, the mating member body 410 and the pin 101 are unlocked. In addition, in order to improve the operation efficiency, structures matched with the locking pieces 420 are arranged on the end parts of different pin shafts 101 of the crane arm joint 100, so that a uniform connection structure is formed, and the operation of plugging and unplugging the pin shafts 101 at multiple positions can be realized by using only one pin pulling device. The locking member 420 may be a bolt, a screw, a clamp with a clamping function, or the like.

Optionally, the transmission rods 300 include a plurality of transmission rods 300, the plurality of transmission rods 300 are arranged in parallel, one end of each of the plurality of transmission rods 300 is rotatably connected to the rack 200, and the other end of each of the plurality of transmission rods 300 is in transmission connection with the mating member 400.

For example, in order to improve stability and smoothness in pin pulling or pin insertion, a plurality of transmission rods 300 may be provided, and in order to avoid interference with each other, the plurality of transmission rods 300 may be provided in parallel with each other. That is, one end of each driving rod 300 is rotatably connected to the frame 200, and the other end thereof is drivingly connected to the mating member 400. In order to enable the mating member 400 to simultaneously and reliably transmit with the plurality of transmission rods 300, and avoid mutual interference, the structures of the plurality of transmission rods 300 are all consistent, wherein one of the transmission rods 300 is an active rod, the transmission rod 300 is connected with the rest of the transmission rods 300 through a synchronous belt, a driving force is applied to the active rod, the other transmission rods 300 are driven by the synchronous belt to synchronously move, and the mating member 400 which is in transmission connection with the other ends of the plurality of transmission rods 300 can smoothly move along the axial direction of the transmission rods 300. As shown in fig. 2, the transmission levers 300 are provided in two, and the two transmission levers 300 are provided centering on the pin 101.

Optionally, the pin pulling device further includes a driving portion 500, the driving portion 500 is rotatably connected to the rack 200, the plurality of transmission rods 300 are disposed with the rotation center ends of the driving portion 500 and the rack 200 as a center, and the rotation center ends of the driving portion 500 are respectively in transmission connection with the plurality of transmission rods 300.

Illustratively, in order to improve the convenience of the pin pulling device, a driving part 500 may be further provided, wherein the driving part 500 is rotatably connected to the frame 200, and ends of a rotation center of the driving part 500 connected to the frame 200 are respectively in transmission connection with the plurality of transmission rods 300. The driving part 500 may be a hand crank as shown in fig. 2, or may be an interface matched with a pulling part of the electric wrench. This embodiment is not particularly limited thereto. The driving part 500 is disposed at a position between the transmission rods 300, so that the transmission rods 300 can be operated synchronously, and the interference of the engaging member 400 disposed at the other end due to asynchronous operation can be avoided. In addition, in order to avoid abrasion caused when the driving part 500 rotates relative to the frame 200, the driving part 500 may be connected to the frame 200 through the bearing 320.

Optionally, a first gear part 310 is further disposed at one end of the plurality of transmission rods 300 close to the rack 200, a second gear part 510 is disposed on the driving part 500, and the second gear part 510 is located at a rotation center of the driving part 500 and the rack 200 and is meshed with the first gear part 310.

Illustratively, a first gear part 310 is disposed at one end of the plurality of transmission rods 300 near the rack 200, and a second gear part 510 is disposed at the driving part 500, and the first gear part 310 is disposed centering on the second gear part 510. When the number of the transmission rods 300 is two, as shown in fig. 2, one transmission gear is provided at an end of each transmission rod 300, and one transmission gear is provided at the driving part 500, and a transmission relationship is established by engaging the two transmission gears with each other. In addition, when there are three transmission rods 300, they are still centered on the second gear unit 510 disposed on the driving unit 500, and the rotation direction of each transmission rod 300 is identical according to the transmission principle of gears. By adopting gear transmission, not only stable and reliable transmission can be provided, but also the transmission accuracy can be effectively improved.

Alternatively, the diameter of the second gear part 510 is smaller than the diameter of the first gear part 310.

For example, as shown in fig. 2, the diameter of the second gear unit 510 is smaller than the diameter of the first gear unit 310, so that the insertion and extraction of the pin 101 can be completed with a small external force. It should be noted that fig. 2 shows only one-stage reduction gear, and when the second gear portion 510 includes a plurality of gears engaged with each other or the first gear portion 310 includes many gears engaged with each other, a two-stage reduction gear, a three-stage reduction gear, and other mechanisms that can save more external force may be further provided.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a pin pulling device, is applied to hoist, its characterized in that includes: the transmission mechanism comprises a rack, a transmission rod and a fitting part matched with the transmission rod; the frame is used for being connected with an arm support of the crane, one end of the transmission rod is rotatably connected with the frame, the other end of the transmission rod is in transmission connection with the fitting piece, the fitting piece is used for being connected with a pin shaft at the joint of the crane arm joint, the transmission rod rotates around the axis of the transmission rod, and the fitting piece is driven to move axially along the transmission rod so as to drive the pin shaft to be separated from the joint of the crane arm joint.

2. The pin pulling apparatus as claimed in claim 1, wherein a through hole is provided on the mating member, and the mating member is sleeved on the outer periphery of the transmission rod through the through hole.

3. The pin puller according to claim 2, wherein single threads are provided on an outer periphery of the driving rod and an inner periphery of the through hole of the mating member, respectively, to be engaged with each other.

4. The pin pulling apparatus as claimed in claim 2, wherein the transmission rod is a reciprocating screw, and a protrusion for engaging with a thread groove of the reciprocating screw is provided on an inner circumference of the through hole of the mating member.

5. The pin puller according to claim 1, wherein a bearing is provided at an end of the drive rod, the end of the drive rod being rotatably connected to the frame via the bearing.

6. The pin pulling apparatus as claimed in claim 1, wherein the engaging member includes an engaging body engaged with the driving rod and a locking member provided on the engaging body, and the engaging body is locked to or unlocked from the pin shaft by the locking member.

7. The pin pulling device as claimed in claim 1, wherein the transmission rod comprises a plurality of transmission rods, the plurality of transmission rods are arranged in parallel, one end of each of the plurality of transmission rods is rotatably connected with the frame, and the other end of each of the plurality of transmission rods is in transmission connection with the mating member.

8. The pin pulling device according to claim 7, further comprising a driving part rotatably connected to the frame, wherein the plurality of driving rods are disposed with the driving part and a rotation center end of the frame as a center, and the rotation center end of the driving part is respectively in transmission connection with the plurality of driving rods.

9. The pin pulling apparatus as claimed in claim 8, wherein a first gear portion is further provided at each of ends of the plurality of transmission rods adjacent to the frame, and a second gear portion is provided at the driving portion, the second gear portion being located at a rotation center of the driving portion and the frame and meshing with the first gear portion.

10. The pin pulling apparatus of claim 9, wherein the second gear portion has a diameter smaller than a diameter of the first gear portion.