Self-locking mechanism of bolt action gun and installation method
By designing a lock cylinder and unlocking mechanism inside the bolt handle of a bolt-action breech, the safety hazard of automatic unlocking during firing is solved, achieving self-locking and convenient unlocking, thus improving the safety and operability of the firearm.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHONGQING JIANSHE IND GRP
- Filing Date
- 2026-04-28
- Publication Date
- 2026-06-23
AI Technical Summary
Traditional bolt-action rifles and sniper rifles pose a safety hazard because the bolt can automatically unlock during firing due to vibration, propellant gas pressure, and the rifling helix angle.
Design a self-locking mechanism for a bolt-action breechblock. By setting a lock cylinder and unlocking mechanism inside the bolt handle, and utilizing the cooperation of the lock cylinder spring, lock pin, flexible push rod and lock head, automatic locking and manual unlocking can be achieved.
It effectively prevents the bolt from automatically unlocking during firing, improving safety, and is easy to operate, meeting the requirements for bolt use.
Smart Images
Figure CN122258698A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of firearms technology, and in particular to a self-locking mechanism and installation method for a bolt-action breechblock. Background Technology
[0002] Traditional bolt-action rifles and sniper rifles primarily utilize a series of key mechanisms—expelling the cartridge, locking, and ejecting the spent cartridge—through a combination of pushing and pulling the bolt forward and backward, and manual rotation. Throughout this process, the bolt handle is manually operated, supporting the bolt's movement and reducing the rotational torque required for locking and unlocking, allowing for awareness of the engagement position. However, during locking, aside from the mutual compression between the locking lugs, there are no mechanisms restricting circumferential rotation. During firing, the projectile is propelled forward by the combustion gases inside the propellant. Guided by the helical rifling inside the barrel, the projectile experiences a small counter-rotational force on the cartridge case at the moment of ejection. Simultaneously, significant pressure is generated within the barrel and chamber, causing the cartridge case to recoil. The projectile vibrates upon exiting the muzzle due to the gases, flame, and kinetic energy. Because the bolt carrier is in close contact with the cartridge base, and the bolt and locking surfaces have a certain helical angle, the vibrations and forces generated by the barrel and bolt can cause a bolt without a locking mechanism to automatically unlock without manual intervention. Automatic unlocking of bolt-action weapons can cause extremely serious injury to both the weapon itself and the operator. To prevent such accidents, this structural solution is invented. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a self-locking mechanism and installation method for a bolt-action breechblock. By designing a lock cylinder and unlocking mechanism inside the bolt handle, a self-locking function is achieved in cooperation with the bolt body latch.
[0004] The objective of this invention is achieved as follows: A self-locking mechanism for a bolt-action breechblock includes a body and a handle. The handle has a bending angle. The body has a square groove, and one end of the handle is inserted into the square groove. The handle is used to manually control the movement of the bolt. The mechanism is characterized by: a mounting base on the outer surface of the body, the mounting base corresponding to the square groove; a lock cylinder and a lock cylinder spring inside the mounting base; the lock cylinder protruding from the mounting base under the action of the lock cylinder spring; the protruding end of the lock cylinder having rounded corners; the rounded corners are used to cooperate with the handle to achieve automatic repositioning of the lock cylinder; and a lock cylinder limiting hole on the insertion end of the handle. The handle has a bending hole along the axis, and a lock pin return spring, a lock pin, a flexible push rod, and a button are arranged in sequence in the bending hole. A lock head is provided on one side of the lock pin. The lock head is perpendicular to the lock pin and is in the shape of a stepped shaft. The lock head slides in the lock core limiting hole on the handle and is axially positioned by the stepped surface. The large diameter end of the lock head and the corresponding end of the lock pin are set as mutually cooperating inclined surfaces. Automatic locking process: When the bolt handle is rotated to the locked position, the bolt is locked in place, and the lock cylinder extends into the lock cylinder limiting hole under the action of the lock cylinder spring to lock the position of the bolt handle; Manual unlocking process: Press the button, the button pushes the flexible push rod forward, the flexible push rod pushes the lock pin forward, the lock pin drives the small diameter end of the lock head to extend through the inclined surface, the small diameter end of the lock head pushes the lock cylinder out of the lock cylinder limiting hole, and releases the position lock of the handle.
[0005] Preferably, the operating end of the handle is threadedly fitted with a handle sleeve, and the flexible push rod and button are fixedly connected. One end of the button is threaded with a fixing sleeve, which slides inside the handle sleeve. The other end of the button is used for pressing.
[0006] Preferably, the flexible push rod adopts a helical spring structure, and the button is fixed by threaded engagement between the flexible push rod and the threaded hole.
[0007] Preferably, the pitch of the helical spring is equal to the diameter of the spring wire.
[0008] Preferably, the mounting base is threaded with a lock cylinder fixing screw, which axially locks the position of the lock cylinder spring and adjusts the lock cylinder ejection force.
[0009] A method for installing a self-locking mechanism of a bolt-action breechblock includes the following steps: S1. Insert the fixing screw into the handle sleeve, and tighten the button and fixing screw using a flathead screwdriver; S2. Insert the flexible push rod into the handle hole and screw the handle sleeve with the button installed onto the connecting thread of the handle; S3. Install the lock cylinder and lock cylinder spring into the body in sequence, tighten the lock cylinder fixing screw, and adjust the lock cylinder ejection force by the tightening depth; S4. Insert the handle into the square slot on the machine body; S5. Stand the machine body upright, keep the lock cylinder limiting hole vertical, insert the lock head vertically into the lock cylinder limiting hole, and rotate the beveled tip of the lock head so that the beveled tip is close to the rotation axis of the handle. S6. Insert the locking pin and locking pin return spring into the bottom of the bending hole of the handle in sequence; the inclined surface of the locking pin is parallel to the inclined surface of the lock head; S7. Use a slotted screwdriver to compress the locking pin return spring, causing the locking pin return spring to make way for the machine head. The machine head has a countersunk plate. Insert the machine head into the rotating hole of the handle to release the locking pin return spring. The locking pin return spring sinks into the countersunk plate for positioning. S8. Install the retaining ring on the machine head to secure the machine head and body.
[0010] Due to the adoption of the above technical solution, the present invention has the following beneficial effects: Enhanced safety: Practical use has proven that this structure can effectively prevent the bolt from automatically unlocking, thus solving the safety hazard of non-human automatic unlocking of the bolt in traditional bolt-action rifles due to vibration, propellant gas pressure, and rifling helix angle during firing.
[0011] Easy to operate: Locking is completed automatically, and unlocking only requires pressing a button, meeting the requirements for bolt operation.
[0012] High structural adaptability: The flexible push rod design cleverly adapts to the bending structure of the handle, avoiding the problem of rigid push rods getting stuck or unable to be installed in the bending path, and ensuring the reliable movement of the mechanism in a limited space. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the overall structure of the bolt carrier; Figure 2 This is a schematic diagram of the cross-sectional structure of the lock body and lock cylinder; Figure 3 This is a schematic diagram of the installation of the handle and the head; Figure 4 This is a schematic diagram of the internal connections of the locking mechanism; Figure 5 This is a cross-sectional view of the internal structure of the handle; Figure 6 This is a schematic diagram of the nose section structure; Figure 7 This is a schematic diagram of the handle structure; Figure 8 This is a schematic diagram of the lock cylinder structure; Figure 9 This is a schematic diagram of the locking pin return spring structure; Figure 10 This is a schematic diagram of the lock pin structure; Figure 11 This is a schematic diagram of a flexible push rod structure; Figure 12 This is a schematic diagram of the handle sleeve structure; Figure 13 This is a schematic diagram of the button fixing screw sleeve structure; Figure 14 This is a schematic diagram of the button structure; Figure 15 This is a schematic diagram of the lock cylinder structure; Figure 16 This is a schematic diagram of the lock core spring structure; Figure 17 This is a schematic diagram of the lock cylinder fixing screw structure. Detailed Implementation
[0014] The invention will be further described below with reference to the accompanying drawings, in which: 1-body, 2-handle, 3-head, 4-handle sleeve, 5-button, 6-lock cylinder, 7-lock cylinder spring, 8-lock cylinder fixing screw, 9-lock post return spring, 10-lock head, 11-lock post, 12-flexible push rod, 13-fixing screw sleeve; A-retaining ring, B-square groove, C-sunken platform, D-lock post mounting hole, E-lock cylinder limiting hole, F-sloping tip.
[0015] A self-locking mechanism for a bolt-action breechblock includes a bolt body 1 and a bolt handle 2. The bolt handle 2 has a bending angle. The bolt body 1 has a square groove B. One end of the bolt handle 2 is inserted into the square groove B of the bolt body 1. The bolt handle 2 is used to manually control the movement of the bolt. A mounting seat is provided on the outer surface of the bolt body 1, and the position of the mounting seat corresponds to the square groove B. A locking cylinder 6 and a locking cylinder spring 7 are provided in the mounting seat. The locking cylinder 6 extends out of the mounting seat under the action of the locking cylinder spring 7. The extended end of the locking cylinder 6 has rounded corners, which are used to cooperate with the bolt handle 2 to realize the automatic retraction of the locking cylinder 6. The insertion end of the bolt handle 2 has a locking cylinder limiting hole E. The handle 2 has a bending hole along the axis, and the bending hole is provided with a lock pin return spring 9, a lock pin 11, a flexible push rod 12, and a button 5 in sequence. A lock head 10 is provided on one side of the lock pin 11. The lock head 10 is perpendicular to the lock pin 11 and is in the shape of a stepped shaft. The lock head 10 is slidably fitted in the lock cylinder limiting hole on the handle 2 and is axially positioned by the stepped surface. The large diameter end of the lock head 10 and the corresponding end of the lock pin 11 are set as mutually cooperating inclined surfaces. Automatic locking process: When the bolt handle 2 is rotated to the locked position, the bolt is locked in place, and the lock cylinder 6 is positioned in the lock cylinder limiting hole E under the action of the lock cylinder spring 7, locking the position of the bolt handle 2. The rounded corner of the lock cylinder head exceeds the limiting hole (or the chamfered part of the limiting hole), restricting the rotation of the bolt handle 2 and preventing automatic unlocking caused by shooting vibration. Manual unlocking process: Press button 5, button 5 pushes the flexible push rod 12 forward, the flexible push rod 12 pushes the lock pin 11 forward, the lock pin 11 drives the small diameter end of the lock head 10 to extend through the inclined surface, the small diameter end of the lock head 10 pushes the lock cylinder 6 out of the lock cylinder limiting hole E (or when the rounded corner of the lock cylinder overlaps with the chamfer of the limiting hole), releasing the position lock of the handle 2, which can be freely rotated to unlock. After that, the lock pin return spring 9 drives the lock pin 11 to return to its original position.
[0016] The operating end of the handle 2 is threadedly fixed to the handle sleeve 4. A flexible push rod 12 and a button 5 are fixedly connected. One end of the button has a threaded fixing sleeve that slides within the handle sleeve. The other end of the button is used for pressing. The flexible push rod 12 uses a helical spring structure, and the button 5 is fixed to the handle 5 via a threaded hole. The pitch of the helical spring is equal to the diameter of the spring wire. A locking screw 8 is threaded onto the mounting base, axially locking the position of the locking spring 7.
[0017] Specifically: This invention designs an automatic locking mechanism based on the relationship between the handle and the body.
[0018] This invention fully utilizes the internal structure of the bolt carrier and handle, the flexible push rod, and the angle difference in the design of the locking mechanism to solve the problem of self-locking function after bolt-action rifles and sniper rifles are locked, eliminate the hidden danger of automatic unlocking of the locking mechanism, and can also be quickly unlocked by hand, meeting the operation and use requirements of the bolt.
[0019] When the bolt is locked, that is, when the bolt handle is rotated to the locked position, the bolt carrier contains a locking mechanism consisting of a spring and a round-headed locking cylinder. When the bolt handle is in the locked position, the locking cylinder automatically extends into the limiting hole of the bolt handle. This prevents the bolt handle from rotating automatically during firing, thus suppressing the rotational forces generated by the bolt's recoil, vibration, and helical lead during firing.
[0020] The lock cylinder is driven by a spring at the rear. The portion of the lock cylinder extending into the lock cylinder limiting hole exceeds the rounded corner of the head. The lock cylinder will not retract under the guidance of the rounded arc surface due to forced rotation of the handle. When the handle and lock cylinder move axially backward without external force, the handle is absolutely locked.
[0021] A flexible push rod and a beveled unlocking mechanism are designed inside the bolt handle. Because bolt handles in bolt-action rifles have a certain bending angle to meet operational requirements, a flexible push rod was invented to achieve mechanical thrust and movement within the bent barrel wall, considering both structural and performance considerations. When the bolt needs to be unlocked, the user holds the bolt handle and presses the button with their palm. The button pushes the flexible push rod, which in turn moves the beveled locking pin forward. The angle difference of the locking pin's bevel pushes out the locking head, pushing out the portion of the locking cylinder embedded in the locking cylinder's limiting hole. This pushed-out portion corresponds to the distance of the bevel angle difference of the locking pin. When the round head of the locking cylinder overlaps with the chamfer of the bolt handle's limiting hole, the bolt handle can disengage from the locking cylinder and rotate freely. After the bolt is self-locking, it can be easily unlocked during normal firing operations using a simple button.
[0022] The components of this invention include: The body serves as the mounting base for the lock cylinder and lock cylinder spring, and also as the fixing base for the machine head and handle.
[0023] The handle is the main component of the locking mechanism of this invention. The handle has a certain bending angle and is a hand-held component for operating the bolt movement and opening and closing the lock. It has a curved hole designed along the axis, through which the lock head, lock pin, flexible push rod and lock pin return spring are installed. It also serves as the fixed base for the handle sleeve and is the main body of the bolt self-locking mechanism.
[0024] Flexible push rods utilize the flexibility of helical springs to adapt to changes in bending positions within curved holes. When the pitch equals the spring wire diameter, it can function as a push rod, eliminating elastic deformation along the axial direction.
[0025] The handle sleeve, the fixing base of the button and the button fixing screw sleeve are the grips for operating the bolt.
[0026] The lock cylinder and the lock pin have a certain angled bevel at the contact point. The distance difference of the overlapping bevels is used to make the lock cylinder extend and retract.
[0027] The installation method includes the following steps: 1. Insert the button retaining sleeve into the threaded hole of the handle sleeve, and tighten the button and retaining sleeve with a slotted screwdriver.
[0028] 2. Insert the flexible push rod into the handle hole, and screw the handle sleeve with the button installed onto the handle connecting thread.
[0029] 3. Install the lock cylinder and lock cylinder spring into the machine body in sequence, and tighten the lock cylinder fixing screw. Adjust the lock cylinder ejection force by tightening the screw; the deeper the screw is tightened, the greater the spring force.
[0030] 4. Insert the handle into the square slot (B) of the machine body.
[0031] 5. Stand the machine body upright and keep the lock cylinder limiting hole vertical. Insert the lock head vertically into the lock cylinder limiting hole and rotate the beveled tip (F) of the lock head close to the rotation axis of the handle.
[0032] 6. Insert the locking pin and locking pin return spring sequentially into the locking pin mounting hole (D) at the bottom of the handle. The inclined surface of the locking pin is parallel to the inclined surface of the lock head.
[0033] 7. Use a slotted screwdriver to compress the lock pin return spring, insert the machine head into the rotating hole of the machine handle, and ensure that the lock pin return spring sinks into the countersunk plate (C).
[0034] 8. Install the retaining ring (A) to secure it.
[0035] 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 self-locking mechanism for a bolt-action breechblock, comprising a body and a bolt handle, the bolt handle having a bending angle, a square groove provided on the body, one end of the bolt handle being inserted into the square groove of the body, the bolt handle being used for manually controlling the movement of the bolt, characterized in that: The outer casing of the mechanism has a mounting base, which corresponds to a square slot. The mounting base contains a lock cylinder and a lock cylinder spring. The lock cylinder extends out of the mounting base under the action of the lock cylinder spring. The extended end of the lock cylinder has rounded corners, which are used to engage with the handle, allowing the lock cylinder to automatically reposition itself. The insertion end of the handle has a lock cylinder limiting hole. The handle has a bending hole along the axis, and a lock pin return spring, a lock pin, a flexible push rod, and a button are arranged in sequence in the bending hole. A lock head is provided on one side of the lock pin. The lock head is perpendicular to the lock pin and is in the shape of a stepped shaft. The lock head slides in the lock core limiting hole on the handle and is axially positioned by the stepped surface. The large diameter end of the lock head and the corresponding end of the lock pin are set as mutually cooperating inclined surfaces. Automatic locking process: When the bolt handle is rotated to the locked position, the bolt is locked in place, and the lock cylinder extends into the lock cylinder limiting hole under the action of the lock cylinder spring to lock the position of the bolt handle; Manual unlocking process: Press the button, the button pushes the flexible push rod forward, the flexible push rod pushes the lock pin forward, the lock pin drives the small diameter end of the lock head to extend through the inclined surface, the small diameter end of the lock head pushes the lock cylinder out of the lock cylinder limiting hole, and releases the position lock of the handle.
2. The self-locking mechanism of a bolt-action breechblock according to claim 1, characterized in that: The operating end of the handle is threadedly fitted with a handle sleeve. The flexible push rod and button are fixedly connected. One end of the button is threaded with a fixing sleeve, which slides inside the handle sleeve. The other end of the button is used for pressing.
3. The self-locking mechanism of a bolt-action breechblock according to claim 1, characterized in that: The flexible push rod adopts a helical spring structure, and the button is fixed by threaded engagement between the threaded hole and the flexible push rod.
4. The self-locking mechanism of a bolt-action breechblock according to claim 3, characterized in that: The pitch of a helical spring is equal to the diameter of the spring wire.
5. The self-locking mechanism of a bolt-action breechblock according to claim 1, characterized in that: The mounting base is threaded with a lock cylinder fixing screw, which axially locks the position of the lock cylinder spring and adjusts the lock cylinder ejection force.
6. A method for installing the self-locking mechanism of the bolt-action bolt as described in claim 1, characterized in that, Includes the following steps: S1. Insert the fixing screw into the handle sleeve, and tighten the button and fixing screw using a flathead screwdriver; S2. Insert the flexible push rod into the handle hole and screw the handle sleeve with the button installed onto the connecting thread of the handle; S3. Install the lock cylinder and lock cylinder spring into the body in sequence, tighten the lock cylinder fixing screw, and adjust the lock cylinder ejection force by the tightening depth; S4. Insert the handle into the square slot on the machine body; S5. Stand the machine body upright, keep the lock cylinder limiting hole vertical, insert the lock head vertically into the lock cylinder limiting hole, and rotate the beveled tip of the lock head so that the beveled tip is close to the rotation axis of the handle. S6. Insert the locking pin and locking pin return spring into the bottom of the bending hole of the handle in sequence; the inclined surface of the locking pin is parallel to the inclined surface of the lock head; S7. Use a slotted screwdriver to compress the locking pin return spring, causing the locking pin return spring to make way for the machine head. The machine head has a countersunk plate. Insert the machine head into the rotating hole of the handle to release the locking pin return spring. The locking pin return spring sinks into the countersunk plate for positioning. S8. Install the retaining ring on the machine head to secure the machine head and body.