A method for assembling a recoil spring in a shotgun

Abstract

This invention discloses a method for assembling a shotgun recoil spring, enabling convenient and quick assembly of the shotgun recoil spring. The method includes the following steps: S1, preparing tools, including a guide tube, a spring sleeve, and a punch; S2, installing the spring sleeve; S3, installing the recoil spring to the guide tube; S4, assembling the recoil spring.

Description

Technical Field

[0001] This invention relates to the field of firearm assembly technology, and in particular to a method for assembling a recoil spring in a shotgun. Background Technology

[0002] To reduce the overall length of the shotgun and achieve maximum energy storage with the same amount of compression, some shotgun models use a rectangular spring wire recoil spring, which is installed in the recoil spring cylinder at the rear of the lower receiver. The free length of the recoil spring is up to 800 mm, and the length after assembly is 260 mm.

[0003] The shotgun recoil spring is currently installed manually. First, insert one end of the free-length recoil spring into the bottom of the recoil spring cylinder's retaining hole. Then, manually compress the entire recoil spring into the recoil spring cylinder's retaining hole. Next, insert the buffer into the recoil spring's inner hole and rotate the buffer to lock it onto the limiting protrusion on the edge of the retaining hole at the rear end of the lower receiver, thus completing the recoil spring installation.

[0004] The toolless assembly process of the aforementioned recoil spring is extremely laborious and difficult to operate, especially when compressing the recoil spring into the recoil spring cylinder's receiving hole. As the spring force increases, manual assembly becomes very difficult and can easily injure the hands. Furthermore, since the lower receiver is made of aluminum alloy with a hard anodized surface, the recoil spring is prone to tilting and swaying left and right or up and down during the assembly and compression process. The surface treatment layer on the upper part of the lower receiver and around the receiving hole is easily worn away by the recoil spring and cannot be repaired. This brings great difficulties and burdens to the assembler in ensuring assembly quality and production organization. Because the assembly method is difficult to master, users dare not easily disassemble the recoil spring during daily maintenance, which can easily lead to problems with the shotgun due to improper maintenance. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for assembling the recoil spring of a shotgun, which can realize the convenient and quick assembly of the shotgun recoil spring.

[0006] The objective of this invention is achieved as follows:

[0007] A method for assembling a recoil spring in a shotgun includes the following steps:

[0008] S1. Prepare tools

[0009] The tools include a guide tube, a spring sleeve, and a punch;

[0010] The guide tube (1) is in the shape of a straight cylinder. The guide tube (1) has a guide section (102), a relief groove section, and a gripping section (104) in sequence. The relief groove section is provided with a relief groove (103) along the longitudinal direction.

[0011] The compression spring sleeve (2) is cylindrical. One end of the compression spring sleeve (2) is provided with a symmetrical step, and the other end of the compression spring sleeve (2) is a gripping section (202). A through clearance hole (203) is provided on the compression spring sleeve (2) along the radial direction. The clearance hole (203) is located between the symmetrical step and the gripping section (202).

[0012] The punch (3) is in the shape of a stepped shaft, with the small end of the punch (3) being the guide section (301) and the large end of the punch (3) being the handle section (303);

[0013] S2. Install the compression spring sleeve.

[0014] Place the spring sleeve (2) onto the guide cylinder (1) so that the relief hole (203) on the spring sleeve (2) is aligned with the relief groove (103) on the guide cylinder (1). Then, insert the guide section (301) of the punch (3) through the relief hole (203) of the spring sleeve (2) into the relief groove (103) of the guide cylinder (1).

[0015] S3. Install the recoil spring to the guide cylinder.

[0016] The free-length recoil spring (6) is fitted onto the guide section (102) of the guide cylinder (1). The first end face (601) of the recoil spring (6) is flush with the end face (101) of the guide cylinder (1). The second end face (604) of the recoil spring (6) is limited by the large end face (205) of the symmetrical step of the compression spring sleeve (2).

[0017] S4, Assemble the recoil spring

[0018] First, insert the guide cylinder (1) and the recoil spring (6) into the inner hole (401) of the recoil spring cylinder (4) so ​​that the end face (101) of the guide cylinder (1) is aligned with the bottom (402) of the inner hole of the recoil spring cylinder (4);

[0019] Afterwards, the punch (3) drives the spring sleeve (2) to slide along the guide cylinder (1), compressing the recoil spring (6) until the symmetrical steps of the recoil spring (6) and the spring sleeve (2) are completely inserted into the spring hole (503) of the lower casing (5). The spring hole (503) can allow the recoil spring (6) to pass through. At this time, the symmetrical steps are distributed vertically.

[0020] Then, rotate the compression spring sleeve (2) so that the symmetrical steps are distributed laterally. The step surface (204) of the symmetrical steps of the compression spring sleeve (2) fits against the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5). The limiting protrusion (502) limits the recoil spring (6) and the compression spring sleeve (2) axially. Then, pull out the punch (3) and the guide cylinder (1).

[0021] Next, insert the guide section (301) of the punch (3) into the gap of the recoil spring (6) and push the recoil spring (6) backward to disengage the recoil spring (6) from the compression spring sleeve (2). Then rotate and remove the compression spring sleeve (2). The punch (3) will no longer push the recoil spring (6), and the recoil spring (6) will return to its original position. By moving the punch (3) laterally, the second end face (604) of the recoil spring (6) will be laterally offset so that the second end face (604) of the recoil spring (6) will press against the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5). Then remove the punch (3) to achieve temporary axial positioning of the recoil spring (6).

[0022] Finally, insert the outer cylindrical surface (702) of the buffer (7) into the inner hole (603) of the recoil spring (6), align the large end clearance notch (703) of the buffer (7) with the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5), and press the buffer (7) in so that the second end face (604) of the recoil spring (6) fits against the positioning step surface (701) on the buffer (7). Move the large end of the buffer (7) to the rear of the limiting protrusion (502), and then rotate the buffer (7) clockwise to lock the large end face (704) of the buffer (7) onto the limiting protrusion (502) on the edge of the spring hole (503) at the rear end of the lower casing (5), thus completing the installation of the recoil spring (6).

[0023] The limiting protrusion (502) is L-shaped. When the recoil spring (6) is in the center, the limiting protrusion (502) does not limit the recoil spring (6). The recoil spring (6) can be axially limited by the limiting protrusion (502) in the biased state. The limiting protrusion (502) is finally engaged and positioned with the large end face (704) of the buffer (7).

[0024] Due to the adoption of the above technical solution, the present invention has the following beneficial effects:

[0025] In this invention, the assembly tool guide cylinder can position and constrain the positioning head so that it does not protrude from the large end mounting hole of the recoil spring on the scale base, which facilitates the assembly of the recoil spring; the spherical groove on the assembly tool punch can position and constrain the pointed tip of the conical part of the positioning head, and a little force can be pressed in to make the positioning head slightly recessed into the large end mounting hole of the recoil spring on the scale base, which facilitates the installation of the guide cylinder.

[0026] This assembly method features simple and practical tools, convenient and quick assembly operations, and no damage to the surface of parts. In particular, it allows shotgun users to easily disassemble, maintain, and assemble the recoil spring without special training. It can greatly improve the efficiency of recoil spring assembly operations in factories and the convenience of daily maintenance operations for gun users. It also greatly reduces the failure rate of this series of shotguns caused by improper maintenance.

[0027] The assembly method involved in this invention has great promotion and practical value in firearm maintenance, and its widespread application will generate good economic and social benefits. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the assembly structure of the recoil spring in a shotgun;

[0029] Figure 2 This is a schematic diagram of the tool guide tube.

[0030] Figure 3 This is a schematic diagram of the tool compression spring sleeve;

[0031] Figure 4 This is a schematic diagram of the tool punch;

[0032] Figure 5 This is a schematic diagram of the recoil spring cylinder;

[0033] Figure 6 This is a structural schematic diagram of the lower casing;

[0034] Figure 7 This is a schematic diagram of the recoil spring structure;

[0035] Figure 8 This is a schematic diagram of the buffer structure;

[0036] Figures 9a-9g This is a schematic diagram of the assembly steps for a shotgun recoil spring.

[0037] Figure Labels

[0038] In the attached diagram, 1-guide cylinder, 2-compression spring sleeve, 3-punch, 4-return spring sleeve, 5-lower casing, 6-return spring, 7-buffer; 101-guide cylinder end face, 102-guide section, 103-relief groove, 104-grip section, 201-inner hole, 202-grip section, 203-relief hole, 204-stepped surface, 205-large end face, 301-guide section, 302-stepped surface, 303-handle section, 401-inner hole, 402-bottom of inner hole, 501-upper plane, 502-limiting protrusion (see...) Figure 1 , is an L-shaped bend for axial positioning), 503-spring hole, 601-first end face, 602-outer cylindrical surface, 603-inner cylindrical surface, 604-second end face, 701-positioning step surface, 702-outer cylindrical surface, 703-large end clearance notch, 704-large end face. Detailed Implementation

[0039] The invention will be further described below with reference to the accompanying drawings.

[0040] See Figures 9a-9gA method for assembling a recoil spring in a shotgun, wherein the recoil spring cylinder and the lower receiver are fixedly connected, and the recoil spring assembly method includes the following steps:

[0041] S1. Prepare tools

[0042] Guide cylinder, spring sleeve, punch;

[0043] The guide cylinder 1 is cylindrical with a gripping section 104 at one end and a relief groove 103, a guide section 102, and an end face 101 at the other end. The width K1 of the relief groove 103 is greater than the diameter D5 of the guide section 301 of the punch 3. The length L2 of the relief groove is greater than the compression length of the recoil spring 6. The starting length L3 of the relief groove is greater than the length of the compression spring sleeve 2. The outer diameter D1 of the guide cylinder is less than the inner diameter D9 of the recoil spring. The length L1 of the guide cylinder is greater than the free length L5 of the recoil spring.

[0044] The compression spring sleeve 2 is cylindrical and has an inner hole 201, a gripping section 202, a clearance hole 203, a symmetrical step 204, and a large second end face 205. The diameter D3 of the inner hole 201 is larger than the outer diameter D1 of the guide cylinder, the diameter D4 of the clearance hole 203 is larger than the diameter D5 of the guide section 301 of the punch 3, the diameter D2 of the large second end face 205 is smaller than the diameter D8 of the spring-receiving hole 503 on the rear end face of the lower casing 5, and the width K2 of the large second end face 205 is smaller than the width K3 of the limiting protrusion 502 on the rear end face of the lower casing 5.

[0045] The punch 3 is in the shape of a stepped shaft. From front to back, the punch consists of a guide section 301, a stepped surface 302, and a handle section 303. The diameter D5 of the guide section 301 is smaller than the diameter D4 of the relief hole 203 of the compression spring sleeve, and the length L4 of the guide section 301 is greater than the outer diameter of the recoil spring 6.

[0046] The width K3 of the limiting protrusion 502 on the rear end face of the lower casing 5 is equal to the outer diameter D10 of the recoil spring 6;

[0047] S2. Install the compression spring sleeve.

[0048] Insert the spring sleeve 2 into the outside of the guide cylinder 1, align the relief hole 203 on the spring sleeve 2 with the relief groove 103 on the guide cylinder 1, and then pass the punch 3 through the relief hole 203 on the spring sleeve 2 and the relief groove 103 on the guide cylinder 1.

[0049] S3. Install the recoil spring to the guide cylinder.

[0050] A free-length recoil spring 6 is fitted onto the outer cylindrical surface 102 of the guide cylinder 1. The first end face 601 of the recoil spring 6 is flush with the first end face 01 of the guide cylinder 1, and the other end 604 is limited by the large second end face 205 on the compression spring sleeve 2.

[0051] S4, Assemble the recoil spring

[0052] First, insert the guide cylinder 1 into the inner hole 401 of the recoil spring cylinder 4 at the rear of the lower casing 5, so that the first end face 01 of the guide cylinder 1 is aligned with the bottom 402 of the inner hole 401 of the recoil spring cylinder 4.

[0053] Next, slide the compression spring sleeve 2 along the guide cylinder 1 to compress the recoil spring 6 until the recoil spring and the large second end face 05 and the stepped surface 204 of the compression spring sleeve 2 are completely inserted into the spring receiving hole 503 at the rear end of the lower casing 5.

[0054] Then, rotate the spring sleeve 2 clockwise so that the stepped surface 204 of the spring sleeve 2 fits against the limiting protrusion 502 on the edge of the spring hole 503 at the rear end of the lower casing 5, and then pull out the punch 3 and the guide cylinder 1.

[0055] Next, insert the punch 3 into the recoil spring 6 and push it backward to compress the recoil spring 6. Then rotate it counterclockwise and remove the spring sleeve 2. Laterally offset the second end face 604 of the recoil spring 6 so that the second end face 604 of the recoil spring 6 presses against the limiting protrusion 502 on the edge of the spring hole 503 at the rear end of the lower casing 5. Then remove the punch 3.

[0056] Finally, insert the outer cylindrical surface 702 of the buffer 7 into the inner hole 603 of the recoil spring 6, so that the end face 604 of the recoil spring 6 fits against the positioning step surface 701 on the buffer 7; flush the large end clearance notch 703 of the buffer 7 with the limiting protrusion 502 on the edge of the spring hole 503 at the rear end of the lower casing 5 and press it in; then rotate the buffer 7 clockwise to lock the large end face 704 onto the limiting protrusion 502 on the edge of the spring hole 503 at the rear end of the lower casing 5, thus completing the installation of the recoil spring 6.

[0057] See Figure 1 Figure 9 shows that the guide cylinder 1 is cylindrical and has a first end face 01, a guide section 102, a relief groove 103, and a gripping section 104 arranged sequentially. The outer diameter D1 of the guide cylinder is smaller than the inner diameter D9 of the recoil spring and smaller than the inner diameter D3 of the compression spring sleeve 2. The length L1 of the guide cylinder is greater than the free length L5 of the recoil spring and the length L6 of the compression spring sleeve 2, and is used to guide the recoil spring and the compression spring sleeve. The width K1 of the relief groove 103 is greater than the diameter D5 of the guide section 301 of the punch 3. The length L2 of the relief groove is greater than the length L7 of the recoil spring 6 after assembly. The starting length L3 of the relief groove is greater than the length L6 of the compression spring sleeve 2. These are key structural dimensions for installing the compression spring sleeve 2 and the punch 3 and guiding the compression of the recoil spring. The corresponding labels on the figure are: D1 < D3, D1 < D9, L1 > L5 + L6, K1 > D5, L2 > L7, L3 > L6.

[0058] The compression spring sleeve 2 is cylindrical and has an inner hole 201, a gripping section 202, a clearance hole 203, a symmetrical step 204, and a large second end face 205. The diameter D3 of the inner hole 201 is larger than the outer diameter D1 of the guide cylinder 1, the diameter D4 of the clearance hole 203 is larger than the diameter D5 of the guide section 301 of the punch 3, the diameter D2 of the large second end face 205 is smaller than the diameter D8 of the spring-collecting hole 503 on the rear end face of the lower casing 5, and the width K2 of the large second end face 205 is smaller than the width K3 of the limiting protrusion 502 on the rear end face of the lower casing 5. This is a key structure for compressing the recoil spring into the spring-collecting hole 503 on the rear end face of the lower casing 5 and limiting its movement, which facilitates the installation of the buffer in the next step. The corresponding labels on the figure are: D1 < D3, D4 > D5, D2 < D8, K2 < K3.

[0059] The punch 3 is a stepped shaft shape, consisting of a guide section 301, a stepped surface 302, and a handle section 303 from front to back. The diameter D5 of the guide section 301 is smaller than the diameter D4 of the clearance hole 203 of the compression spring sleeve, and the length L4 of the guide section 301 is greater than the outer diameter D10 of the recoil spring 6. The corresponding markings on the diagram are: D5 < D4, L4 > D10.

[0060] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for assembling a recoil spring in a shotgun, characterized in that, Includes the following steps: S1. Prepare tools The tools include a guide tube, a spring sleeve, and a punch; The guide tube (1) is in the shape of a straight cylinder. The guide tube (1) consists of a guide tube guide section (102), a relief groove section, and a guide tube grip section (104) in sequence. The relief groove section is provided with a relief groove (103) along the longitudinal direction. The compression spring sleeve (2) is cylindrical. One end of the compression spring sleeve (2) is provided with a symmetrical step, and the other end of the compression spring sleeve (2) is a compression spring sleeve grip section (202). A through clearance hole (203) is provided on the compression spring sleeve (2) along the radial direction. The clearance hole (203) is located between the symmetrical step and the compression spring sleeve grip section (202). The punch (3) is in the shape of a stepped shaft, with the small end of the punch (3) being the punch guide section (301) and the large end of the punch (3) being the handle section (303). S2. Install the compression spring sleeve. Place the spring sleeve (2) onto the guide cylinder (1) so that the relief hole (203) on the spring sleeve (2) is aligned with the relief groove (103) on the guide cylinder (1). Then, insert the punch guide section (301) of the punch (3) through the relief hole (203) of the spring sleeve (2) into the relief groove (103) of the guide cylinder (1). S3. Install the recoil spring to the guide cylinder. The free-length recoil spring (6) is fitted onto the guide section (102) of the guide cylinder (1). The first end face (601) of the recoil spring (6) is flush with the end face (101) of the guide cylinder (1). The second end face (604) of the recoil spring (6) is limited by the large end face (205) of the symmetrical step of the compression spring sleeve (2). S4, Assemble the recoil spring First, insert the guide cylinder (1) and the recoil spring (6) into the inner hole (401) of the recoil spring cylinder (4) so ​​that the end face (101) of the guide cylinder (1) is aligned with the bottom (402) of the inner hole of the recoil spring cylinder (4); Afterwards, the punch (3) drives the compression spring sleeve (2) to slide along the guide cylinder (1), compressing the recoil spring (6) until the symmetrical steps of the recoil spring (6) and the compression spring sleeve (2) are completely inserted into the spring hole (503) of the lower casing (5). At this time, the symmetrical steps are distributed vertically. Then, rotate the compression spring sleeve (2) so that the symmetrical steps are distributed laterally. The step surface (204) of the symmetrical steps of the compression spring sleeve (2) fits against the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5). The limiting protrusion (502) limits the recoil spring (6) and the compression spring sleeve (2) axially. Then, pull out the punch (3) and the guide cylinder (1). Next, insert the punch guide section (301) of the punch (3) into the gap of the recoil spring (6), and push the recoil spring (6) backward to disengage the recoil spring (6) from the pressure spring sleeve (2). Then rotate and remove the pressure spring sleeve (2). The punch (3) will no longer push the recoil spring (6). The recoil spring (6) will return to its original position. Laterally offset the second end face (604) of the recoil spring (6) so that the second end face (604) of the recoil spring (6) rests on the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5). Then remove the punch (3). Finally, insert the outer cylindrical surface (702) of the buffer (7) into the inner hole (603) of the recoil spring (6), align the large end clearance notch (703) of the buffer (7) with the limiting protrusion (502) on the edge of the spring hole (503) of the lower casing (5), and press the buffer (7) in so that the second end face (604) of the recoil spring (6) fits against the positioning step surface (701) on the buffer (7). Move the large end of the buffer (7) to the back of the limiting protrusion (502), and then rotate the buffer (7) clockwise to lock the large end face (704) of the buffer (7) onto the limiting protrusion (502) on the edge of the spring hole (503) at the rear end of the lower casing (5), thus completing the installation of the recoil spring (6).

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