Pin puller and method of use

Abstract

This invention discloses a pin puller and its usage method, comprising: a pin puller screw, the pin puller screw including a first end and a second end, the first end having a first connecting portion for connecting with the workpiece to be disassembled; a pin puller sliding sleeve movably sleeved on the outside of the pin puller screw; a pin puller cam sleeve, sleeved on the pin puller screw and located on the first side of the pin puller sliding sleeve, the side wall of the pin puller cam sleeve having a plurality of locking screws, the pin puller cam sleeve being detachably locked and fixed to an external camshaft by the locking screws; and a pin puller threaded sleeve, fixedly disposed on the second end of the pin puller screw and located on the second side of the pin puller sliding sleeve; by simultaneously providing the pin puller cam sleeve and the pin puller threaded sleeve on the pin puller screw, and placing the pin puller sliding sleeve between the two, the operator can select the sliding direction of the sliding sleeve as needed, impacting the pin puller threaded sleeve can disassemble the bearing, and impacting the pin puller cam sleeve can move the camshaft.

Description

Technical Field

[0001] This invention relates to the field of mechanical disassembly tools, and more specifically, to a pin puller and its usage method. Background Technology

[0002] A pin puller (also known as a gravity screwdriver) is a commonly used hand tool in mechanical repair and assembly. It is mainly used to disassemble locating pins, cylindrical pins, tapered pins, and various bearings, as well as other difficult-to-remove connecting parts. The working principle of a traditional pin puller is usually to generate impact force by sliding a sliding hammer on a sliding rod, and then use inertia to pull the pin or bearing out of the mounting hole.

[0003] In existing technologies, pin pullers typically consist of a striker and a hammer, with multiple cavities within the hammer to accommodate tool heads of different sizes. However, traditional pin pullers have a relatively limited function, usually only capable of unidirectional impact disassembly. In actual mechanical equipment maintenance and assembly scenarios, operators often need to carry multiple different types of disassembly tools to meet various disassembly needs; for example, they may need to disassemble bearings and move camshafts. Frequent tool changes not only reduce work efficiency but also increase tool storage and management costs.

[0004] Furthermore, existing pin pullers have a relatively simple method of fixing to the camshaft and lack a reliable axial positioning structure. They are prone to loosening or displacement when subjected to large impact forces, affecting the safety and reliability of operation. At the same time, the cam sleeves of existing pin pullers are mostly single sleeve structures, which have poor connection stability with the camshaft and make it difficult to efficiently transmit impact forces to the camshaft to achieve axial movement of the cam. Summary of the Invention

[0005] To solve at least one of the above-mentioned technical problems, the present invention proposes a pin puller and a method of using it.

[0006] The first aspect of the present invention provides a pin puller, comprising: A pin puller screw, the pin puller screw including a first end and a second end, the first end being provided with a first connecting portion for connecting with the workpiece to be disassembled; A pin puller sleeve is movably sleeved on the outside of the pin puller screw; A pin puller cam sleeve is sleeved on the pin puller screw and located on the first side of the pin puller sliding sleeve. The side wall of the pin puller cam sleeve is provided with a plurality of anti-screw mounting holes. Anti-screws are provided in the anti-screw mounting holes. The pin puller cam sleeve is detachably locked and fixed to the external camshaft by the anti-screws. A pin puller threaded sleeve is fixedly disposed at the second end of the pin puller screw and located on the second side of the pin puller sliding sleeve; Specifically, by sliding the pin puller sleeve in a direction from the first side toward the second side, the pin puller sleeve strikes the pin puller threaded sleeve, generating a first impact force for disassembling the bearing; by sliding the pin puller sleeve in a direction from the second side toward the first side, the pin puller sleeve strikes the pin puller cam sleeve, generating a second impact force for moving the cam.

[0007] In a preferred embodiment of the present invention, a through hole is provided on the side wall of the pin puller cam sleeve, the through hole being used for inserting an external tool to rotate the pin puller cam sleeve.

[0008] In a preferred embodiment of the present invention, the pin puller cam sleeve is divided into a locking section, a transition section and an impact section in sequence along the axial direction. The mounting hole for the stop screw is provided in the locking section, the through hole is provided in the impact section, and the end face of the impact section is a flat annular end face that has been quenched.

[0009] In a preferred embodiment of the present invention, there are four mounting holes for the anti-screws, which are evenly distributed on the circumference of the side wall of the pin puller cam sleeve. The anti-screws are M6 specification anti-screws, and the four anti-screws are tightened and locked in a diagonal order.

[0010] In a preferred embodiment of the present invention, the mounting hole for the anti-loosening screw is a cylindrical through hole or a T-shaped stepped hole structure. The T-shaped stepped hole structure includes a large diameter section and a small diameter section. The small diameter section is provided with an internal thread to cooperate with the anti-loosening screw. An anti-loosening washer is provided between the stepped surface between the large diameter section and the small diameter section and the head of the anti-loosening screw.

[0011] In a preferred embodiment of the present invention, the pin puller threaded sleeve includes a threaded connection section and a flange impact section. The threaded connection section has a central threaded hole inside that is connected to the second end of the pin puller screw. The outer diameter of the flange impact section is larger than the outer diameter of the threaded connection section. The end face of the flange impact section facing the pin puller sleeve is a flat annular end face that has been quenched.

[0012] In a preferred embodiment of the present invention, the threaded sleeve of the pin puller is further provided with a receiving cavity. The receiving cavity is located inside the flange impact section and is coaxially connected with the central threaded hole. The diameter of the receiving cavity is larger than the diameter of the central threaded hole. The receiving cavity is used to accommodate the head of the internal hexagonal socket head cap screw.

[0013] A second aspect of the present invention provides a method for using a pin puller, applicable to a pin puller, comprising the following steps: S1, the pin puller cam sleeve is locked and fixed to the external camshaft by the stop screw; S2, pass the pin puller screw through the axial through hole of the pin puller cam sleeve, so that the first end of the pin puller screw is connected to the workpiece to be disassembled or the cam to be moved; S3, the pin puller sleeve is movably positioned outside the pin puller screw; S4, the threaded sleeve of the pin puller is fixedly disposed at the second end; S5, When it is necessary to disassemble the bearing, slide the pin puller sleeve in the direction from the first side to the second side, so that the pin puller sleeve hits the pin puller threaded sleeve, and the resulting impact force is transmitted to the workpiece to be disassembled through the pin puller screw, and the needle roller bearing that has been installed in the output shaft is brought out. S6, when it is necessary to move the cam, slide the pin puller sleeve in the direction from the second side toward the first side, so that the pin puller sleeve hits the pin puller cam sleeve, and the resulting impact force is transmitted to the external camshaft through the pin puller cam sleeve, moving the cam axially.

[0014] In a preferred embodiment of the present invention, step S7 is further included: when it is only necessary to rotate the camshaft without axial movement or disassembly, the pin puller screw, the pin puller sliding sleeve and the pin puller threaded sleeve are removed from the pin puller cam sleeve, an external tool is inserted into the pin puller cam sleeve, and the pin puller cam sleeve is rotated with the axis of the camshaft as the rotation center, thereby driving the camshaft to rotate to the required angle.

[0015] In a preferred embodiment of the present invention, in step S2, the internal hexagon socket head cap screw is passed through the center hole of the needle roller bearing, and the external thread of the first end of the pin puller screw is screwed into the internal thread hole of the internal hexagon socket head cap screw and tightened.

[0016] The technical solution of the present invention has the following advantages compared with the prior art: This invention, by simultaneously installing a pin-pulling cam sleeve and a pin-pulling threaded sleeve on the pin-pulling screw, and placing a pin-pulling sliding sleeve between the two, allows the operator to select the sliding direction of the sliding sleeve as needed. Impacting the pin-pulling threaded sleeve disassembles the bearing, while impacting the pin-pulling cam sleeve moves the camshaft. The same tool set can perform two different disassembly tasks, improving the tool's versatility and efficiency.

[0017] This invention features multiple locking screws on the side wall of the cam sleeve of the pin puller, which securely fix the cam sleeve to the camshaft through a multi-point circumferential locking method. Compared to the traditional single sleeve connection method, this locking structure can withstand greater impact loads, maintain positional stability during repeated impacts of the sliding sleeve, and improve operational safety and reliability.

[0018] The present invention provides a through hole on the side wall of the pin puller cam sleeve. The operator can insert an external tool into the through hole to rotate the pin puller cam sleeve, thereby driving the camshaft to rotate, which facilitates the angle adjustment or fine-tuning of the cam, and further expands the functional range of the tool.

[0019] The pin puller screw, pin puller sleeve, pin puller cam sleeve, and pin puller threaded sleeve of this invention are all independent modular parts, which are convenient to manufacture and easy to assemble and disassemble. At the same time, the pin puller screw and pin puller sleeve can be used as general-purpose parts, and can be used with different pin puller cam sleeves and pin puller threaded sleeves, which have good interchangeability and expandability.

[0020] The method of the sliding sleeve directly impacting the threaded sleeve or cam sleeve in this application can efficiently convert the kinetic energy of the sliding sleeve into axial impact force, reduce energy loss in intermediate transmission links, and improve disassembly efficiency. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, some of the drawings in the following description are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the pin puller being inserted into the turntable according to the present invention; Figure 2 This is a schematic diagram of the cam sleeve of the pin puller of the present invention used alone; Figure 3 This is a three-dimensional structural diagram of the pin puller of the present invention; Figure 4 This is a schematic diagram of the cross-section of the pin puller of the present invention; Figure 5 This is a schematic diagram of the cross-section of the cam sleeve of the pin puller of the present invention.

[0023] In the diagram, 1. Turntable, 2. Pin puller threaded sleeve, 3. Pin puller screw, 4. Pin puller sliding sleeve, 5. Pin puller cam sleeve, 6. Roller, 7. Socket head cap screw, 8. Set screw, 9. Camshaft, 10. External tool. Detailed Implementation

[0024] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0026] Example 1 See Figures 1-5 As shown, the present invention proposes a pin puller, comprising: The pin puller screw 3 includes a first end and a second end, and the first end is provided with a first connecting part for connecting with the workpiece to be disassembled. The pin puller sliding sleeve 4 is movably sleeved on the outside of the pin puller screw 3; The pin puller cam sleeve 5 is sleeved on the pin puller screw 3 and located on the first side of the pin puller sliding sleeve 4. The side wall of the pin puller cam sleeve 5 is provided with multiple mounting holes for the stop screws 8. The stop screws 8 are installed in the mounting holes. The pin puller cam sleeve 5 is detachably locked and fixed to the external camshaft 9 by the stop screws 8. The pin puller threaded sleeve 2 is fixedly installed at the second end of the pin puller screw 3 and located on the second side of the pin puller sliding sleeve 4, with the first side and the second side corresponding to each other; Specifically, by sliding the pin puller sleeve 4 in the direction from the first side to the second side, the pin puller sleeve 4 impacts the pin puller threaded sleeve 2, generating a first impact force for disassembling the bearing; by sliding the pin puller sleeve 4 in the direction from the second side to the first side, the pin puller sleeve 4 impacts the pin puller cam sleeve 5, generating a second impact force for moving the cam.

[0027] According to an embodiment of the present invention, a through hole is provided on the side wall of the pin puller cam sleeve 5, the through hole being used for the insertion of an external tool 10 to rotate the pin puller cam sleeve 5.

[0028] According to an embodiment of the present invention, the pin puller cam sleeve 5 is divided into a locking section, a transition section and an impact section in sequence along the axial direction. The mounting hole of the stop screw 8 is provided in the locking section, and the through hole is provided in the impact section. The end face of the impact section is a flat annular end face that has been quenched.

[0029] According to an embodiment of the present invention, there are four mounting holes for the anchor screws 8, which are evenly distributed on the circumference of the side wall of the pin puller cam sleeve 5. The anchor screws 8 are M6 specification anchor screws 8, and the four anchor screws 8 are tightened and locked in sequence in diagonal order.

[0030] According to an embodiment of the present invention, the mounting hole of the anchor screw 8 is a stepped hole structure, including a large diameter section and a small diameter section. The small diameter section is provided with an internal thread to cooperate with the anchor screw 8. An anti-loosening washer is provided between the stepped surface between the large diameter section and the small diameter section and the head of the anchor screw 8.

[0031] The specific implementation method of the locking structure of the anchor screw 8 is as follows: The set screw 8 is an M6-sized internal hexagonal socket head cap screw with a concave end. When locked, the concave end is embedded in a pre-set pit or keyway on the surface of the camshaft 9 to achieve anti-loosening locking and effectively prevent the set screw 8 from loosening under impact and vibration.

[0032] The mounting hole for the set-off screw 8 is a stepped hole structure, consisting of a large-diameter section and a small-diameter section. The diameter of the large-diameter section (the end closest to the outer wall of the puller cam sleeve 5) is slightly larger than the head diameter of the set-off screw 8, used to accommodate the head of the set-off screw 8, ensuring that the set-off screw 8 is recessed into the mounting hole and does not protrude from the outer surface of the cam sleeve. The small-diameter section (the end closest to the camshaft 9) has an internal thread that mates with the external thread of the set-off screw 8. The stepped surface between the large-diameter and small-diameter sections is used to limit the screw-in depth of the set-off screw 8.

[0033] In an improved embodiment, each mounting hole of the set screw 8 is further provided with an anti-loosening washer (such as a spring washer or a toothed locking washer). The anti-loosening washer is fitted onto the thread of the set screw 8 and is located between the head of the set screw 8 and the stepped surface. After the set screw 8 is tightened, the anti-loosening washer is in a compressed state, continuously providing axial elastic force, so that the threaded parts of the set screw 8 maintain friction, further preventing loosening under impact and vibration.

[0034] Preferably, the four locking screws 8 are tightened in a diagonal sequence during locking (i.e., the first, third, second, and fourth screws are tightened in sequence) to ensure that the locking section of the pin puller cam sleeve 5 is evenly stressed, and to avoid eccentric deformation of the cam sleeve due to excessive tightening on one side, which would affect the passage of the pin puller screw 3 in the axial through hole.

[0035] According to an embodiment of the present invention, the threaded sleeve 2 of the pin puller includes a threaded connection section and a flange impact section. The threaded connection section has a central threaded hole inside that is connected to the second end of the pin puller screw 3. The outer diameter of the flange impact section is larger than the outer diameter of the threaded connection section. The end face of the flange impact section facing the pin puller sliding sleeve 4 is a flat annular end face that has been quenched.

[0036] According to an embodiment of the present invention, the threaded sleeve 2 of the pin puller is further provided with a receiving cavity inside. The receiving cavity is located inside the flange impact section and is coaxially connected with the central threaded hole. The diameter of the receiving cavity is larger than the diameter of the central threaded hole. The receiving cavity is used to receive the head of the internal hexagonal socket head cap screw 7. A roller 6 is provided on one side of the turntable 1. An internal hexagonal socket head cap screw 7 is provided on the roller 6. The threaded sleeve 2 of the pin puller is sleeved on the outside of the internal hexagonal socket head cap screw 7 for pulling out the roller 6.

[0037] The assembly and use of the pin puller are as follows: The complete structure of the pin puller includes four main components: the pin puller screw 3, the pin puller sliding sleeve 4, the pin puller cam sleeve 5, and the pin puller threaded sleeve 2.

[0038] The assembly process is as follows: First, the cam sleeve 5 of the pin puller is pre-locked and fixed to the camshaft 9 to be operated by four M6 locking screws 8 to ensure that there is no relative movement between the cam sleeve and the camshaft 9.

[0039] Then, the first end of the pin puller screw 3 (i.e. the end with external threads) is passed through the axial through hole of the pin puller cam sleeve 5 and connected to the needle roller bearing to be disassembled or the camshaft 9 to be moved.

[0040] The specific connection method is as follows: First, pass the internal hexagon socket head cap screw 7 through the inner hole of the needle roller bearing, and tighten the first end of the puller screw 3 to the internal hexagon socket head cap screw 7.

[0041] Next, the pin puller sleeve 4 is inserted from the second end (i.e. the end away from the first end) of the pin puller screw 3, so that the pin puller sleeve 4 is slidably disposed on the pin puller screw 3 and located between the pin puller cam sleeve 5 and the pin puller threaded sleeve 2.

[0042] Finally, screw the threaded sleeve 2 of the pin puller onto the second end of the pin puller screw 3 to complete the assembly of the entire pin puller.

[0043] The usage process is as follows: When it is necessary to disassemble the needle roller bearing, the operator holds the pin puller sleeve 4 and slides it along the pin puller screw 3 in a direction away from the pin puller cam sleeve 5 (i.e., towards the pin puller threaded sleeve 2, referred to as the first direction). When the pin puller sleeve 4 strikes the pin puller threaded sleeve 2, the kinetic energy of the sleeve is converted into an axial impact force. This impact force is transmitted to the needle roller bearing through the pin puller threaded sleeve 2, the pin puller screw 3, and the internal hexagon socket head cap screw 7, thus pulling the needle roller bearing out of the output shaft.

[0044] When the cam needs to be moved, the operator holds the pin puller sleeve 4 and slides it along the pin puller screw 3 in a direction away from the pin puller threaded sleeve 2 (i.e., towards the pin puller cam sleeve 5, referred to as the second direction). When the pin puller sleeve 4 strikes the pin puller cam sleeve 5, the kinetic energy of the sleeve is converted into a reverse axial impact force. This impact force is transmitted to the camshaft 9 through the pin puller cam sleeve 5, pushing the cam axially to the desired position.

[0045] Through the bidirectional sliding impact method described above, the pin puller in this embodiment integrates the functions of bearing disassembly and cam movement, allowing operators to complete two different disassembly tasks without changing tools.

[0046] In one specific embodiment of the present invention, in certain usage scenarios, the pin puller cam sleeve 5 can also be used alone without the need for the pin puller screw 3, the pin puller sliding sleeve 4, and the pin puller threaded sleeve 2.

[0047] When used alone, the pin puller cam sleeve 5 is locked to the camshaft 9 by the four M6 locking screws 8 on the left. The operator can insert an external tool 10 (such as a pry bar) into the ø12 through hole on the right and directly rotate the pin puller cam sleeve 5, thereby driving the camshaft 9 to rotate. This standalone use method is suitable for scenarios where only the angle of the camshaft 9 needs to be adjusted without the need for pin pulling or disassembly.

[0048] Example 2 A second aspect of the present invention provides a method for using a pin puller, applicable to a pin puller, comprising the following steps: S1, the pin puller cam sleeve 5 is locked and fixed to the external camshaft 9 by the locking screw 8; In step S1, the specific method for locking and fixing the pin puller cam sleeve 5 to the external camshaft 9 is as follows: tighten the four locking screws 8 in diagonal order, with a tightening torque of 8 N·m-12 N·m.

[0049] S2, pass the pin puller screw 3 through the axial through hole of the pin puller cam sleeve 5, so that the first end of the pin puller screw 3 is connected to the workpiece to be disassembled or the cam to be moved; S3, the pin puller sleeve 4 is movably positioned outside the pin puller screw 3; S4, the threaded sleeve 2 of the pin puller is fixedly installed at the second end; S5, when it is necessary to disassemble the bearing, slide the pin puller sleeve 4 in the direction from the first side to the second side, so that the pin puller sleeve 4 hits the pin puller threaded sleeve 2, and the resulting impact force is transmitted to the workpiece to be disassembled through the pin puller screw 3, which will bring out the needle roller bearing that has been installed in the output shaft. S6, when the cam needs to be moved, slide the pin puller sleeve 4 in the direction from the second side to the first side, so that the pin puller sleeve 4 hits the pin puller cam sleeve 5, and the resulting impact force is transmitted to the external camshaft 9 through the pin puller cam sleeve 5, which moves the cam axially.

[0050] Specifically, the impact force is adjusted by selecting different weights of the pin puller sleeve 4, which is selected from one of the weight specifications of 0.5kg, 1.0kg, 1.5kg and 2.0kg.

[0051] According to an embodiment of the present invention, step S7 is further included: when it is only necessary to rotate the camshaft 9 without axial movement or disassembly, the pin puller screw 3, the pin puller sliding sleeve 4 and the pin puller threaded sleeve 2 are removed from the pin puller cam sleeve 5, the external tool 10 is inserted into the pin puller cam sleeve 5, and the pin puller cam sleeve 5 is rotated with the axis of the camshaft 9 as the rotation center, thereby driving the camshaft 9 to rotate to the required angle.

[0052] According to an embodiment of the present invention, in step S2, the internal hexagonal socket head cap screw 7 is passed through the center hole of the needle roller bearing, and the external thread of the first end of the pin puller screw 3 is screwed into the internal thread hole of the internal hexagonal socket head cap screw 7 and tightened.

[0053] In one specific embodiment of the present invention, the method of using the pin puller is as follows: bearing disassembly mode: Preparation before operation: Confirm that the pin puller cam sleeve 5 is securely locked to the camshaft 9 by the four M6 locking screws 8. Confirm that the first connecting section of the pin puller screw 3 is fixedly connected to the needle roller bearing to be disassembled by the hex socket head cap screw 7. Confirm that the pin puller threaded sleeve 2 is securely screwed into the second end of the pin puller screw 3.

[0054] Operating Procedure: The operator holds the gripping part of the pin puller sleeve 4 with one hand and accelerates the sliding of the pin puller sleeve 4 along the pin puller screw 3 in a direction away from the pin puller cam sleeve 5 (i.e., towards the pin puller threaded sleeve 2, referred to as the first direction). When the sleeve reaches the end of its stroke, the second impact end face of the pin puller sleeve 4 impacts the left end face of the flange impact section of the pin puller threaded sleeve 2 at a speed v1.

[0055] According to the momentum theorem, the kinetic energy E=1 / 2mv1² of the pin puller sleeve 4 is instantly converted into an impact force F1. This impact force is transmitted through the pin puller threaded sleeve 2, pin puller screw 3, internal hexagon socket head cap screw 7, and needle roller bearing, and acts on the needle roller bearing in the form of axial tension, pulling the needle roller bearing out of the output shaft.

[0056] The operator can repeat the above sliding-impact action multiple times. After each impact, the needle roller bearing is pulled out a certain distance until the bearing is completely separated from the output shaft. During repeated operation, if the threaded connection between the first connecting section of the pin puller screw 3 and the internal hexagon socket head cap screw 7 becomes loose, it can be tightened at any time by rotating the pin puller threaded sleeve 2 or by inserting a wrench into the internal hexagon socket groove.

[0057] Parameter Selection: For bearings of different specifications, operators can adjust the impact force by replacing the pin puller sleeve 4 with different masses (e.g., sleeves with masses of 0.5kg, 1.0kg, 1.5kg, and 2.0kg). The theoretical calculation value of the impact force satisfies F1 = m·v1 / t, where t is the impact contact time (usually 0.001s-0.005s). For example, when the sleeve mass m = 1.0kg, the sliding speed v1 = 5m / s, and the contact time t = 0.002s, the generated impact force F1 = 2500N, which is sufficient to disassemble most small and medium-sized bearings.

[0058] Preferably, the maximum sliding speed v1max of the pin puller sleeve 4 is determined by the sliding stroke S of the sleeve and the thrust applied by the operator. In actual operation, it is recommended to control the impact frequency to 20-40 times per minute to avoid operator fatigue or equipment damage due to excessively fast operation.

[0059] In another specific embodiment of the present invention, the method of using the pin puller is as follows: the cam movement mode is as follows: Preparation before operation: Confirm that the pin puller cam sleeve 5 is securely locked to the camshaft 9 by the four M6 locking screws 8. Confirm that the first connecting section of the pin puller screw 3 is connected to the camshaft 9 to be moved or the accessories on the camshaft 9 (if no connection is required, the pin puller screw 3 can be pulled out of the cam sleeve, leaving only the cam sleeve for use alone).

[0060] The operating steps include: the operator holds the gripping part of the pin puller sleeve 4 with one hand and accelerates the pin puller sleeve 4 along the pin puller screw 3 in a direction away from the pin puller threaded sleeve 2 (i.e., towards the pin puller cam sleeve 5, referred to as the second direction). When the sleeve reaches the end of its stroke, the first impact end face of the pin puller sleeve 4 impacts the right end face of the impact section of the pin puller cam sleeve 573 at a speed of v2.

[0061] According to the momentum theorem, the kinetic energy E=1 / 2mv2² of the pin puller sleeve 4 is instantly converted into a reverse impact force F2. This impact force is transmitted through the pin puller cam sleeve 5, the four M6 fixing screws 8, and the camshaft 9, and acts on the camshaft 9 in the form of axial thrust, pushing the camshaft 9 axially to the preset position.

[0062] Since the camshaft 9 needs to overcome the frictional force F between itself and the machine base during axial movement, the operator must ensure that the impact force F2 generated by each impact is greater than F in order to achieve gradual axial movement of the camshaft 9. For camshaft 9 with high moving resistance, a heavier pin puller sleeve 4 can be selected or the sliding speed v2 of the sleeve can be increased.

[0063] The standalone use mode includes the following: In scenarios where only rotation of the camshaft 9 is required without axial movement, the operator can remove the pin puller screw 3, pin puller sleeve 4, and pin puller threaded sleeve 2 from the pin puller cam sleeve 5, leaving only the pin puller cam sleeve 5 locked to the camshaft 9 by four M6 locking screws 8. Then, a pry bar or wrench is inserted into the ø12 through hole on the pin puller cam sleeve 5, and the pin puller cam sleeve 5 is rotated around the axis of the camshaft 9, thereby rotating the camshaft 9 to the desired angle. This mode is particularly suitable for camshaft 9 angle adjustment and phase alignment operations.

[0064] This application also provides a method for disassembling and routine maintenance of a pin puller to ensure the tool's service life and operational reliability.

[0065] Disassembly Method: Disassemble in the reverse order of assembly. First, use a wrench to secure the internal hexagonal recess at the end of the second connecting section of the pin puller screw 3, then rotate the pin puller threaded sleeve 2 in the reverse direction to unscrew it from the screw. Next, slide the pin puller sliding sleeve 4 out from the first end of the pin puller screw 3. Then, pull the pin puller screw 3 out of the axial through hole of the pin puller cam sleeve 5 and unscrew it from the workpiece to be disassembled. Finally, loosen the four M6 set screws 8 in diagonal order to remove the pin puller cam sleeve 5 from the camshaft 9. After disassembly, all parts should be cleaned and rust-proofed.

[0066] The maintenance methods specifically include: After each use, remove oil and metal debris from the surfaces of all parts, especially the threaded parts and impact surfaces.

[0067] Regularly inspect the wear condition of the impact end face. When the wear depth of the end face exceeds 0.5mm or obvious plastic deformation occurs, the end face should be ground and repaired or replaced with a new part.

[0068] Regularly check the thread integrity of the stop screw 8. If thread wear, stripping, or deformation of the internal hexagon head is found, it should be replaced in time.

[0069] Before each use, check that all threaded connections are tight, especially the anchor screw 8 to see if it has become loose due to impact or vibration.

[0070] When not in use for an extended period, apply anti-rust oil to the surface of each component and store it in a dry and well-ventilated environment.

[0071] In summary, the technical solution of the present invention has the following advantages compared with the prior art: This invention, by simultaneously installing a pin-pulling cam sleeve 5 and a pin-pulling threaded sleeve 2 on the pin-pulling screw 3, and placing a pin-pulling sliding sleeve 4 between the two, allows the operator to select the sliding direction of the sliding sleeve as needed. Impacting the pin-pulling threaded sleeve 2 disassembles the bearing, while impacting the pin-pulling cam sleeve 5 moves the camshaft 9. The same set of tools can perform two different disassembly tasks, improving the tool's versatility and efficiency.

[0072] This invention features multiple locking screws 8 on the side wall of the cam sleeve 5 of the pin puller, which securely fix the cam sleeve to the camshaft 9 through a multi-point circumferential locking method. Compared with the traditional single sleeve connection method, this locking structure can withstand greater impact loads, maintain positional stability during repeated impacts of the sliding sleeve, and improve operational safety and reliability.

[0073] The present invention provides a through hole on the side wall of the pin puller cam sleeve 5. The operator can insert an external tool 10 into the through hole to rotate the pin puller cam sleeve 5, thereby driving the camshaft 9 to rotate, which facilitates the angle adjustment or position fine adjustment of the cam, and further expands the functional range of the tool.

[0074] The pin puller screw 3, pin puller sliding sleeve 4, pin puller cam sleeve 5, and pin puller threaded sleeve 2 of this invention are all independent modular parts, which are convenient to process and manufacture, and easy and quick to assemble and disassemble. At the same time, the pin puller screw 3 and pin puller sliding sleeve 4 can be used as general-purpose parts, and can be used with different pin puller cam sleeves 5 and pin puller threaded sleeves 2, which have good interchangeability and expandability.

[0075] The method of the sliding sleeve directly impacting the threaded sleeve or cam sleeve in this application can efficiently convert the kinetic energy of the sliding sleeve into axial impact force, reduce energy loss in intermediate transmission links, and improve disassembly efficiency.

[0076] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to the above embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0078] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A pin puller, characterized in that, include: A pin puller screw, the pin puller screw including a first end and a second end, the first end being provided with a first connecting portion for connecting with the workpiece to be disassembled; A pin puller sleeve is movably sleeved on the outside of the pin puller screw; A pin puller cam sleeve is sleeved on the pin puller screw and located on the first side of the pin puller sliding sleeve. The side wall of the pin puller cam sleeve is provided with a plurality of anti-screw mounting holes. Anti-screws are provided in the anti-screw mounting holes. The pin puller cam sleeve is detachably locked and fixed to the external camshaft by the anti-screws. A pin puller threaded sleeve is fixedly disposed at the second end of the pin puller screw and located on the second side of the pin puller sliding sleeve; Specifically, by sliding the pin puller sleeve in a direction from the first side toward the second side, the pin puller sleeve strikes the pin puller threaded sleeve, generating a first impact force for disassembling the bearing; by sliding the pin puller sleeve in a direction from the second side toward the first side, the pin puller sleeve strikes the pin puller cam sleeve, generating a second impact force for moving the cam.

2. A pin puller according to claim 1, characterized in that, The side wall of the pin puller cam sleeve is provided with a through hole, which is used for inserting an external tool to rotate the pin puller cam sleeve.

3. A pin puller according to claim 1, characterized in that, The pin puller cam sleeve is divided into a locking section, a transition section and an impact section along the axial direction. The mounting hole for the stop screw is located in the locking section, and the through hole is located in the impact section. The end face of the impact section is a flat annular end face that has been hardened.

4. A pin puller according to claim 1, characterized in that, The number of mounting holes for the anti-screws is four, which are evenly distributed on the circumference of the side wall of the pin puller cam sleeve. The anti-screws are M6 specification anti-screws, and the four anti-screws are tightened and locked in sequence in diagonal order.

5. A pin puller according to claim 4, characterized in that, The mounting hole for the anti-loosening screw is a cylindrical through hole or a T-shaped stepped hole structure. The T-shaped stepped hole structure includes a large diameter section and a small diameter section. The small diameter section is provided with an internal thread to mate with the anti-loosening screw. An anti-loosening washer is provided between the stepped surface between the large diameter section and the small diameter section and the head of the anti-loosening screw.

6. A pin puller according to claim 1, characterized in that, The pin puller threaded sleeve includes a threaded connection section and a flange impact section. The threaded connection section has a central threaded hole inside that mates with the second end of the pin puller screw. The outer diameter of the flange impact section is larger than the outer diameter of the threaded connection section. The end face of the flange impact section facing the pin puller sleeve is a flat annular end face that has been quenched.

7. A pin puller according to claim 1, characterized in that, The threaded sleeve of the pin puller also has a receiving cavity inside. The receiving cavity is located inside the flange impact section and is coaxially connected with the central threaded hole. The diameter of the receiving cavity is larger than the diameter of the central threaded hole. The receiving cavity is used to accommodate the head of the internal hexagonal socket head cap screw.

8. A method of using a pin puller, applied to the pin puller according to any one of claims 1-7, characterized in that, Includes the following steps: S1, the pin puller cam sleeve is locked and fixed to the external camshaft by the stop screw; S2, pass the pin puller screw through the axial through hole of the pin puller cam sleeve, so that the first end of the pin puller screw is connected to the workpiece to be disassembled or the cam to be moved; S3, the pin puller sleeve is movably positioned outside the pin puller screw; S4, the threaded sleeve of the pin puller is fixedly disposed at the second end; S5, When it is necessary to disassemble the bearing, slide the pin puller sleeve in the direction from the first side to the second side, so that the pin puller sleeve hits the pin puller threaded sleeve, and the resulting impact force is transmitted to the workpiece to be disassembled through the pin puller screw, and the needle roller bearing that has been installed in the output shaft is brought out. S6, when it is necessary to move the cam, slide the pin puller sleeve in the direction from the second side toward the first side, so that the pin puller sleeve hits the pin puller cam sleeve, and the resulting impact force is transmitted to the external camshaft through the pin puller cam sleeve, moving the cam axially.

9. A method of using a pin puller according to claim 8, characterized in that, The method also includes step S7, in which, when only rotation of the camshaft is required without axial movement or disassembly, the pin puller screw, the pin puller sleeve and the pin puller threaded sleeve are removed from the pin puller cam sleeve, an external tool is inserted into the pin puller cam sleeve, and the pin puller cam sleeve is rotated with the axis of the camshaft as the rotation center, thereby driving the camshaft to rotate to the required angle.

10. A method of using a pin puller according to claim 8, characterized in that, In step S2, the internal hexagon socket head cap screw is passed through the center hole of the needle roller bearing, and the external thread of the first end of the pin puller screw is screwed into the internal thread hole of the internal hexagon socket head cap screw and tightened.

Images