Positioning pin mounting tool and assembly method

Abstract

This invention provides a positioning pin installation fixture and assembly method, relating to the field of compressor assembly technology. Addressing the problems of piston damage and adverse scraping / interference during piston pin adjustment, this invention employs a rod with double bends to form a fulcrum and avoidance section, preventing interference and resolving scraping issues. A smooth spherical crown is provided at the end of the rod to prevent damage caused by sharp ends accidentally touching the piston, reducing the impact of piston damage and jamming during positioning pin installation, ensuring assembly accuracy and improving assembly efficiency. A ball is used to form the smooth spherical crown, and the connection between the ball and the rod forms a contraction section. After the smooth spherical crown enters the inner pin hole, the contraction section engages at the intersection of the inner pin hole and the blind hole, creating a hooking effect. This ensures the stable transmission of the rod's adjustment action to the piston pin, achieving circumferential rotation and axial displacement adjustment, meeting the alignment requirements of the inner and outer pin holes.

Description

Technical Field

[0001] This invention relates to the field of compressor assembly technology, specifically to a positioning pin installation fixture and assembly method. Background Technology

[0002] In a reciprocating compressor used in a refrigerator, the piston and connecting rod are connected by a piston pin. The piston has a mounting hole through which the piston pin passes. After the piston pin is pressed into the mounting hole, the circumferential and axial positions of the piston pin and the mounting hole need to be locked. The piston pin end face has a blind hole, and the piston pin has an inner pin hole that connects to the blind hole radially. The piston has an outer pin hole that connects to the mounting hole. A locating pin engages with both the inner and outer pin holes to lock the relative positions of the piston pin and the piston. After the piston pin is installed, the positions of the inner and outer pin holes may not be precisely aligned, requiring adjustment of the piston pin position. Currently, a straight wire is used to probe the piston pin through the blind hole to adjust its alignment. After the inner and outer pin holes are aligned, another operator uses a pressure plate or other tools to press the locating pin into the outer and inner pin holes.

[0003] There is frictional resistance between the piston pin and the mounting hole. When the iron wire moves the piston pin, because the inner wall of the blind hole is relatively smooth, the end of the iron wire needs to enter the inner pin hole to apply force. Currently, there is only one inner pin hole on the piston pin, and the angle is inconsistent each time it is installed. It is necessary to confirm the distribution angle and position of the inner pin hole before quickly inserting the iron wire into the blind hole and adjusting the piston pin circumferentially. At the same time, it is also necessary to lift or press it axially. Due to the distribution characteristics of the U-shaped grooves on the piston and cylinder seat, after one end of the iron wire enters the inner pin hole, when moving the inner pin hole to rotate the piston pin and lifting the piston pin to adjust its axial position, the middle part of the iron wire is prone to interference with the cylinder seat, scraping the U-shaped groove and causing iron filings to fall off and enter the piston and cylinder seat motion system, causing the piston to jam. In addition, iron wires with a small diameter are prone to bending and deformation due to force when moving. Straight iron wires are used to balance rigidity and ease of operation. The end of the wire is a pointed tip. Due to the small size of the blind hole and the inner pin hole, the operator holds the wire in a suspended position and inserts the pointed end through the blind hole into the inner pin hole. During this process, the wire has no other support or positioning position, resulting in a cantilever structure. The operator's hand position is the fixed end, and the pointed end is the cantilever end. During installation, it is easy for the tip to come into contact with the piston, scratching the piston and causing a bulge at the piston-cylinder seat mating position. Since the clearance between the piston and cylinder seat mating position is very small (the clearance is often 3-5 micrometers), once a bulge occurs, it is easy to cause the mating to jam. In addition, the locating pin and the inner pin hole, and the locating pin and the outer pin hole are both interference fits. After the locating pin is aligned and inserted into the outer pin hole, it also needs to be aligned and inserted into the inner pin hole. This process is inconvenient to observe and operate, and since both are interference fits, inserting the locating pin is more difficult and requires two operators to complete. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a locating pin installation fixture and assembly method. It employs a rod with double bends to form a fulcrum and a clearance section to avoid interference and prevent scratching. A smooth spherical crown is provided at the end of the rod to prevent damage caused by sharp ends accidentally touching the piston. This reduces the impact of piston jamming during locating pin installation, ensuring assembly accuracy and improving assembly efficiency.

[0005] The first objective of this invention is to provide a locating pin installation fixture, which adopts the following solution:

[0006] include:

[0007] The handle is for gripping;

[0008] The rod has one end connected to the handle and the other end has a smooth ball crown. The smooth ball crown is used to insert into the piston pin end face to contact the piston pin. The rod has a first bend and a second bend that are spaced apart. The first bend is closer to the handle than the second bend. The convex side of the first bend serves as a fulcrum to abut the cylinder head, and the concave side of the second bend serves as a clearance part to avoid the U-shaped groove of the cylinder seat.

[0009] Furthermore, a bead is connected to the end of the rod away from the handle, and the outer spherical surface of the bead forms a smooth spherical crown outside the connection area of ​​the rod.

[0010] Furthermore, the rod has a smooth chamfer on the outer ring at the point where it connects to the ball, so that the connection between the ball and the rod forms a contraction.

[0011] Furthermore, both the first and second bends are rounded bends, the axes of the corresponding rod segments on both sides of the first bend are perpendicular, and the axes of the corresponding rod segments on both sides of the second bend are perpendicular.

[0012] Furthermore, the axis of the segment between the first bent portion and the handle is parallel to the axis of the segment between the second bent portion and the smooth spherical crown.

[0013] A second objective of this invention is to provide a method for assembling locating pins, utilizing a locating pin mounting fixture as described in the first objective, comprising:

[0014] The handle drives the rod to move, causing one end of the rod's smooth spherical crown to penetrate into the blind hole on the piston pin end face;

[0015] Adjust the position of the rod so that the smooth ball crown partially penetrates the inner pin hole on the piston pin, the fulcrum falls on the cylinder head, and the clearance part is separated from the cylinder seat;

[0016] The rod receives the action of the handle and drives the piston pin to move axially and / or circumferentially, so that the inner pin hole is aligned with the outer pin hole on the piston;

[0017] Insert a flexible locating pin into the outer pin hole, so that the flexible locating pin passes through the outer pin hole and enters the inner pin hole, locking the piston pin and piston position.

[0018] Furthermore, a contraction portion is formed between the rod and the smooth ball crown, and the smooth ball crown abuts against the inner wall of the inner pin hole, with the contraction portion forming a hooking effect.

[0019] Furthermore, the piston pin end face blind hole has multiple inner pin holes evenly distributed circumferentially, and the inner pin holes are distributed radially along the piston pin and are connected to the blind hole respectively.

[0020] Furthermore, the end of the outer pin hole away from the piston pin is provided with a chamfer for guidance, the end of the inner pin hole away from the piston pin axis is also provided with a chamfer for guidance, and the end of the elastic positioning pin used for insertion into the outer pin hole is provided with a chamfer for guidance.

[0021] Furthermore, the outer circumferential surface of the elastic positioning pin is provided with notches distributed along its generatrix direction, so that the elastic positioning pin can form elastic deformation along the ring upward. The elastic positioning pin forms an interference fit with the inner pin hole, and the elastic positioning pin forms a clearance fit with the outer pin hole.

[0022] Compared with the prior art, the advantages and positive effects of this invention are:

[0023] (1) In view of the current problem that the tooling is easy to damage the piston and cause adverse scraping and interference to the piston when adjusting the position of the piston pin, a rod with double bends is used to form a fulcrum and avoidance part to avoid interference and solve the problem of adverse scraping. The end of the rod is equipped with a smooth ball crown to avoid the damage caused by the sharp end accidentally touching the piston, reduce the jamming effect caused by the piston being damaged during the installation of the positioning pin, ensure assembly accuracy and improve assembly efficiency.

[0024] (2) A smooth spherical crown is formed by using a ball. The ball and the rod are connected to form a contraction. After the smooth spherical crown is inserted into the inner pin hole, the contraction is stuck at the intersection of the inner pin hole and the blind hole to form a hooking effect, so that the rod adjustment is stably transmitted to the piston pin, realizing circumferential rotation adjustment and axial displacement adjustment, and meeting the alignment requirements of the inner pin hole and the outer pin hole.

[0025] (3) Multiple inner pin holes are set on the piston pin to reduce the adjustment angle and improve the installation efficiency of the elastic positioning pin.

[0026] (4) The single inner pin hole of the piston pin is optimized into multiple inner pin holes, which facilitates the quick positioning of the piston pin and the locating pin installation fixture, and enables the outer pin hole to be quickly aligned with the nearest inner pin hole. The outer pin hole, inner pin hole and the insertion end of the elastic locating pin are all provided with guide chamfers, which helps the elastic locating pin to be inserted smoothly.

[0027] (5) By changing the elastic locating pin and the outer pin hole to a clearance fit, while the elastic locating pin and the inner pin hole maintain an interference fit, the elastic locating pin can be easily inserted into the clearance fit outer pin hole first, and then pressed into the inner pin hole under the guidance and constraint of the outer pin hole. This simplifies the assembly process and ensures the firmness of the assembly. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] Figure 1 This is a schematic diagram of the locating pin installation fixture in Embodiments 1 and 2 of the present invention.

[0030] Figure 2 This is a schematic diagram of the piston pin in Embodiments 1 and 2 of the present invention.

[0031] Figure 3 This is a schematic diagram of the elastic positioning pin in Embodiments 1 and 2 of the present invention.

[0032] Figure 4 This is a schematic diagram of the fit between the elastic locating pin and the piston pin in Embodiments 1 and 2 of the present invention.

[0033] Figure 5 This is a schematic diagram showing the relative positions of the end ball and the inner pin hole of the rod in Embodiments 1 and 2 of the present invention.

[0034] Figure 6 This is a schematic diagram of the locating pin installation fixture and the installation position of the elastic locating pin in Embodiments 1 and 2 of the present invention.

[0035] Figure 7 This is a schematic diagram of the locating pin installation fixture, piston, and elastic locating pin in Embodiments 1 and 2 of the present invention.

[0036] Among them, 1. Cylinder seat, 2. Piston, 21. Outer pin hole, 3. Piston pin, 31. Blind hole, 32. Inner pin hole, 4. Crankshaft, 5. Connecting rod, 6. Elastic locating pin, 7. Locating pin mounting fixture, 71. Handle, 72. Rod, 73. Ball, 74. Contraction part, 75. First bend, 76. Second bend. Detailed Implementation

[0037] Example 1

[0038] In a typical embodiment of the present invention, such as Figures 1-7 As shown, a positioning pin installation fixture is presented.

[0039] like Figure 7As shown, connecting rod 5 connects to piston 2 via piston pin 3. After the piston pin 3 and the mounting holes on piston 2 are engaged, a locating pin is needed to lock the axial and circumferential positions of piston pin 3 and piston 2 to prevent piston pin 3 from moving or coming off during operation. During the installation of the locating pin, the position of piston pin 3 needs to be adjusted axially or circumferentially. Current auxiliary tooling is prone to damaging the surface of piston 2, and during use, it is easy to cause scraping interference, generating iron filings that adhere to piston 2 and cause problems with piston 2's smooth operation.

[0040] Based on this, this embodiment provides a positioning pin installation fixture 7, including a rod 72 and a handle 71, as shown below. Figure 1 As shown, the shape of the rod 72 is adjusted so that a fulcrum and a clearance part are formed on the rod 72. The fulcrum abuts against the cylinder head to avoid scraping near the piston 2. The clearance part can pass over the U-shaped groove on the cylinder seat 1 so that one end of the smooth ball crown can enter the piston pin 3, avoiding the sharp end from protruding due to scratches, thereby ensuring the smooth operation of the piston 2.

[0041] Figure 1 The structure of the locating pin mounting fixture 7 is shown. The handle 71 is easy to grip, and one end of the rod 72 is connected to the handle 71, while the other end has a smooth spherical crown structure, effectively preventing scratch damage to the piston 2 surface. The rod 72 has a first bend 75 and a second bend 76 spaced apart. The first bend 75 protrudes outward as a fulcrum against the cylinder head, providing stable support; the second bend 76 is concave to avoid the U-shaped groove of the cylinder seat 1, preventing interference and scratching between the locating pin mounting fixture 7 and the U-shaped groove.

[0042] The fulcrum formed by the first bend 75 provides stable support during operation, preventing the positioning pin installation fixture 7 from slipping or damaging components due to uneven force when adjusting the position of the piston pin 3. The second bend 76 has a concave design, effectively preventing the generation of iron filings due to scraping during adjustment, and significantly reducing the potential risk of damage to precision components such as the piston 2 and cylinder seat 1 during operation. In this embodiment, the fulcrum rests on the upper surface of the cylinder head of the cylinder seat 1, avoiding the problem of scraping against the edge of the U-shaped groove of the cylinder seat 1 during installation, preventing iron filings from falling off and causing the cylinder seat 1 and piston 2 to jam, and extending the service life of the compressor.

[0043] The double-bend design ensures the stability of the locating pin mounting fixture 7 during use, avoids unnecessary interference with the cylinder seat 1, reduces iron filings, and thus prevents piston 2 from jamming. This improves assembly accuracy and work efficiency, reduces rework rates, saves production costs, and also enhances the overall quality and performance of the product.

[0044] To address the problem that straight wires with sharp tips can easily puncture or scratch piston 2, such as... Figure 1 and Figure 5 As shown, a ball 73 is connected to the end of the rod 72 away from the handle 71. The outer spherical surface of the ball 73 forms a smooth spherical crown outside the connection area with the rod 72. The smooth spherical crown allows the end of the rod 72 to smoothly enter the end face of the piston pin 3. Even if the smooth spherical crown comes into contact with the compressor surface, it will not cause scratches or punctures, and will avoid the formation of protruding structures on the piston 2 surface. Rotation and axial adjustment are performed by contacting the piston pin 3 with the smooth spherical crown, which improves the operating accuracy and safety.

[0045] Figure 5 The connection between the ball 73 and the rod 72 is shown. The rotation between the piston pin 3 and the mounting hole on the piston 2 is hindered by friction, requiring the rod 72 to apply a large force to the piston pin 3. The ball 73 uses a smooth spherical crown to avoid forming a sharp point, which makes it difficult to form a stable force between the smooth spherical crown and the blind hole 31 of the piston pin 3. Although the smooth spherical surface can be inserted into the inner pin hole 32 of the piston pin 3 to transmit force, it is still easy to dislodge during the force transmission process due to the low friction of the smooth spherical surface. When the piston pin 3 is adjusted for circumferential rotation and axial displacement, it is often difficult to transmit force stably, resulting in inconvenience in the adjustment process of the piston pin 3, unsatisfactory adjustment effect, and even damage to the piston 2.

[0046] To address the aforementioned issues, in this embodiment, a smooth chamfer is provided at the connection between the rod 72 and the ball 73, forming a contraction portion 74. When the smooth ball crown is inserted into the inner pin hole 32, the contraction portion 74 can be engaged at the intersection of the inner pin hole 32 and the blind hole 31, forming a hooking effect, thereby ensuring that the adjustment action of the rod 72 can be stably transmitted to the piston pin 3.

[0047] like Figure 6 As shown, on the one hand, by utilizing the contact of the smooth spherical crown, the locating pin installation fixture 7 can more smoothly enter the blind hole 31 and inner pin hole 32 of the piston pin 3, avoiding the jamming or scratching of the piston 2 that may occur with traditional tools; on the other hand, the setting of the contraction part 74 allows the rod 72 to form a hooking action after entering the inner pin hole 32, ensuring stable force transmission to the piston pin 3 during circumferential rotation or axial displacement adjustment, avoiding the unstable or failed force transmission that may occur with traditional tools; thus meeting the alignment requirements of the inner pin hole 32 and the outer pin hole 21. This improves assembly efficiency and ensures assembly quality. Since the ball 73 and the rod 72 are fixedly connected to form a smooth spherical crown and contraction part 74, the entire locating pin installation fixture 7 can transmit and bear greater force during use, enhancing its durability.

[0048] Both the first bend 75 and the second bend 76 are rounded bends. The axes of the corresponding segments of the first bend 75 and the second bend 76 are perpendicular to each other. The axes of the corresponding segments of the second bend 76 and the first bend 75 are parallel to the axis of the segment between the first bend 75 and the handle 71. This facilitates direction control and improves maneuverability.

[0049] The first bend 75 and the second bend 76 are both rounded bends. This rounded bend design reduces stress concentration, improving the strength and durability of the locating pin mounting fixture 7. Simultaneously, the rounded bends allow for smoother contact between the locating pin mounting fixture 7 and other components, reducing scratches and wear. The axes of the rod segments 72 on both sides of the first bend 75 and the second bend 76 are perpendicular, enabling the locating pin mounting fixture 7 to bend and rotate in a predetermined direction when subjected to force, thus improving its controllability and operational stability.

[0050] The segmental axis between the first bend 75 and the handle 71 is parallel to the segmental axis between the second bend 76 and the smooth spherical crown. This parallel distribution helps maintain the directional consistency of the positioning pin installation fixture 7 during operation, allowing the operator to more accurately control the movement trajectory of the positioning pin installation fixture 7 and further improving operability. This helps improve the installation efficiency and quality of the refrigerator reciprocating compressor piston pin 3, reducing operational difficulty and the risk of damage.

[0051] like Figure 1 As shown, the handle 71 of the locating pin mounting fixture 7 is a spindle-shaped handle, which can be adjusted appropriately in other embodiments for easy gripping. The rod 72 is a rigid rod, and the ball 73 is a steel ball. The length of the rod 72 should be sufficient to ensure it can stably penetrate into the blind hole 31 of the piston pin 3 and drive the piston pin 3 to make necessary movements. The diameter of the rod 72 should be moderate, ensuring sufficient strength to withstand the forces during assembly, while avoiding excessive size that would cause assembly difficulties. Each segment of the rod 72 should have good straightness to ensure accurate guidance of the piston pin 3 during assembly. The diameter of the ball 73 should be slightly smaller than the diameter of the inner pin hole 32 on the piston pin 3 to allow it to smoothly penetrate and hook into the inner pin hole 32; the ball 73 should have good sphericity to ensure good contact with the inner wall of the inner pin hole 32 and to stably support and position the piston pin 3; the material of the ball 73 should have sufficient hardness to withstand the pressure and friction during assembly. The diameter of the contraction section 74 is smaller than the diameter of the rod 72 and the smooth spherical crown. The transition between the contraction section 74 and the rod 72 and the smooth spherical crown should be smooth to avoid stress concentration and scratching during assembly.

[0052] like Figure 2As shown, the piston pin 3 has multiple internal pin holes 32 evenly distributed circumferentially on the blind hole 31 at its end face. Each internal pin hole 32 can cooperate with a locating pin, reducing the adjustment angle during installation and improving adjustment efficiency. Figure 3 As shown, the outer circumference of the locating pin has notches distributed along its generatrix to form an elastic locating pin 6. The elastic locating pin 6 can elastically deform along the ring upward, and the elastic locating pin 6 forms an interference fit with the inner pin hole 32.

[0053] Example 2

[0054] In another typical embodiment of the present invention, such as Figures 1-7 As shown, a method for assembling locating pins is presented.

[0055] The installation of fixture 7 using the locating pin as shown in Example 1 includes the following steps:

[0056] The handle 71 drives the rod 72 to move, so that one end of the smooth ball crown of the rod 72 inserts into the blind hole 31 on the end face of the piston pin 3;

[0057] Adjust the position of rod 72 so that the smooth ball crown partially penetrates the inner pin hole 32 on piston pin 3, the fulcrum falls on cylinder head, and the clearance part cylinder seat 1 is separated;

[0058] The rod 72 receives the action of the handle 71 and drives the piston pin 3 to move axially and / or circumferentially, so that the inner pin hole 32 is aligned with the outer pin hole 21 on the piston 2;

[0059] An elastic positioning pin 6 is inserted into the outer pin hole 21, so that the elastic positioning pin 6 passes through the outer pin hole 21 and enters the inner pin hole 32, locking the position of the piston pin 3 and the piston 2.

[0060] In traditional installation methods, the locating pin and the outer pin hole 21 on piston 2 and the inner pin hole 32 on piston pin 3 are both interference fits, which requires a large pressing force during installation and requires two people to complete. The entire installation process is inconvenient and results in a slow cycle time; the required cycle time is 3 seconds, but it actually takes 6 seconds to complete. In this embodiment, the locating pin assembly method is simple to operate, can significantly improve the cycle time of a single process, and save the physical strength of employees; one person can complete the operation of two people.

[0061] Below, in conjunction with Figures 1-7 The method for assembling locating pins is described in detail in Example 1.

[0062] A method for assembling locating pins includes the following steps:

[0063] Initial positioning: The operator holds the spindle-shaped handle of the positioning pin mounting fixture 7 with their left hand, using the handle 71 of the positioning pin mounting fixture 7 as the operating point to move the rod 72. This causes one end of the smooth spherical crown of the rod 72 to insert into the blind hole 31 on the end face of the piston pin 3, preparing for further positioning.

[0064] Position adjustment: By adjusting the position of the rod 72, the smooth ball crown is partially inserted into the inner pin hole 32 on the piston pin 3. At this time, the fulcrum of the locating pin mounting fixture 7 naturally falls on the cylinder head, ensuring that the clearance part remains separated from the cylinder seat 1.

[0065] Hole alignment: Under the action of the handle 71, the rod 72 drives the piston pin 3 to move axially or circumferentially or both simultaneously, until the inner pin hole 32 is completely aligned with the outer pin hole 21 on the piston 2.

[0066] Positioning pin assembly: Insert the elastic positioning pin 6 into the outer pin hole 21, so that it passes through the outer pin hole 21 and smoothly enters the inner pin hole 32. The positioning pin then locks the relative position of the piston pin 3 and the piston 2.

[0067] The contraction portion 74 formed between the rod 72 and the smooth spherical crown plays a hooking role during the assembly process, which helps to stabilize the position of the piston pin 3.

[0068] Multiple inner pin holes 32 are evenly distributed circumferentially around the blind hole 31 of the piston pin 3. These inner pin holes 32 are radially distributed along the piston pin 3 and communicate with the blind hole 31, providing multiple assembly options. Optimizing a single inner pin hole 32 of the piston pin 3 into four inner pin holes 32 distributed in a cross shape facilitates quick positioning of the piston pin 3 with the locating pin mounting fixture 7, and enables rapid alignment of the outer pin hole 21 with the nearest inner pin hole 32. The outer pin hole 21, inner pin holes 32, and the insertion end of the elastic locating pin 6 are all provided with guide chamfers, which helps in the smooth insertion of the elastic locating pin 6.

[0069] The outer circumference of the elastic locating pin 6 has a notch, which allows it to elastically deform in the circumferential direction. The diameter of the elastic locating pin 6 can be adaptively adjusted during the assembly process to form an interference fit with the inner pin hole 32, ensuring the firmness of the assembly. By changing the elastic locating pin 6 and the outer pin hole 21 to a clearance fit, while the elastic locating pin 6 and the inner pin hole 32 maintain an interference fit, the elastic locating pin 6 can be easily inserted into the clearance fit outer pin hole 21 first, and then pressed into the inner pin hole 32 under the guidance and constraint of the outer pin hole 21. This simplifies the assembly process and ensures the firmness of the assembly.

[0070] It should be noted that in this embodiment, a pin is also used to assist in the insertion of the elastic positioning pin 6. The pin is worn on the operator's right hand finger. After adjusting the positions of the inner pin hole 32 and the outer pin hole 21, the pin is used to press one end of the elastic positioning pin 6 through the outer pin hole 21 and into the inner pin hole 32.

[0071] The locating pin installation fixture 7 can efficiently adjust the position of the piston pin 3, improving the accuracy and efficiency of assembly. The fulcrum of the locating pin installation fixture 7 avoids rubbing against the edge of the U-shaped groove of the cylinder seat 1 during installation, thus preventing jamming caused by falling iron filings.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for assembling locating pins, comprising a locating pin installation fixture, characterized in that, The positioning pin installation fixture includes: The handle is for gripping; The rod has one end connected to the handle and the other end has a smooth ball crown. The smooth ball crown is used to probe into the piston pin end face to contact the piston pin. The rod has a first bend and a second bend that are spaced apart. The first bend is closer to the handle than the second bend. The convex side of the first bend serves as a fulcrum to abut the cylinder head, and the concave side of the second bend serves as a clearance part to avoid the U-shaped groove of the cylinder seat. When in use, the handle drives the rod to move, so that one end of the rod's smooth spherical crown inserts into the blind hole on the piston pin end face; Adjust the position of the rod so that the smooth ball crown partially penetrates the inner pin hole on the piston pin, the fulcrum falls on the cylinder head, the clearance part is separated from the cylinder seat, and the rod receives the action of the handle to drive the piston pin to move axially and / or circumferentially, so that the inner pin hole is aligned with the outer pin hole on the piston. Insert a flexible locating pin into the outer pin hole, so that the flexible locating pin passes through the outer pin hole and enters the inner pin hole, locking the piston pin and piston position.

2. The locating pin assembly method as described in claim 1, characterized in that, A contraction section is formed between the rod and the smooth ball cap, and the smooth ball cap abuts against the inner wall of the inner pin hole, with the contraction section forming a hooking effect.

3. The locating pin assembly method as described in claim 2, characterized in that, The piston pin end face blind hole has multiple inner pin holes evenly distributed circumferentially, and the inner pin holes are distributed radially along the piston pin and are connected to the blind hole respectively.

4. The locating pin assembly method as described in claim 3, characterized in that, The outer pin hole has a chamfer for guidance at the end away from the piston pin, and the inner pin hole also has a chamfer for guidance at the end away from the piston pin axis. The end of the elastic positioning pin that is inserted into the outer pin hole has a chamfer for guidance.

5. The locating pin assembly method as described in claim 4, characterized in that, The outer circumference of the elastic positioning pin is provided with notches distributed along its generatrix, so that the elastic positioning pin can form elastic deformation along the ring upward. The elastic positioning pin forms an interference fit with the inner pin hole, and the elastic positioning pin forms a clearance fit with the outer pin hole.

6. The locating pin assembly method as described in claim 1, characterized in that, A bead is connected to one end of the rod away from the handle, and the outer spherical surface of the bead forms a smooth spherical crown outside the connection area of ​​the rod.

7. The locating pin assembly method as described in claim 6, characterized in that, The rod has a smooth chamfer on the outer ring where it is connected to the bead, so that the connection between the bead and the rod forms a contraction.

8. The locating pin assembly method as described in claim 1, characterized in that, Both the first and second bends are rounded bends. The axes of the corresponding rod segments on both sides of the first bend are perpendicular, and the axes of the corresponding rod segments on both sides of the second bend are perpendicular.

9. The locating pin assembly method as described in claim 8, characterized in that, The axis of the segment between the first bent portion and the handle is parallel to the axis of the segment between the second bent portion and the smooth ball crown.

Images