A latch mechanism for a door lock

Abstract

The utility model belongs to door lock technical field, specifically is a kind of door lock's latch mechanism, including integrally injection moulded latch body and connecting rod, connecting rod is equipped with limit block, baffle and spring through convenient dismounting mechanism assembly, latch body is equipped with metal sheath, convenient dismounting mechanism is matched through the limit protrusion in the assembly ring inside and the assembly slot on connecting rod, assembly slot includes rotating part, into end and limit part, the quick loading and unloading of baffle are realized, metal sheath is fixed through the double positioning structure of positioning column and positioning hole, positioning protrusion and positioning groove, the utility model reduces the quantity of parts and cost, eliminates the connecting stress concentration of split type latch, improves anti-fatigue performance, without tooling can quick dismounting, improve production maintenance efficiency, metal sheath effectively protects latch, prolongs service life, and it has low cost, high reliability and convenient maintenance.

Description

Technical Field

[0001] This utility model belongs to the field of door lock technology, specifically a door lock latch mechanism. Background Technology

[0002] The latch is the core component of a door lock, mainly used to achieve automatic locking and unlocking of the door. It is widely used in various door types in homes, offices and other scenarios. The material is mostly metal or plastic, and it focuses on wear resistance and impact resistance. It is a key component to ensure the reliability of door closure.

[0003] The existing latch structure mainly consists of the following parts: latch body, connecting rod, spring, limit block, baffle, etc. Working principle: When closing the door, the door frame presses the inclined surface of the latch body, pushes the connecting rod to compress the spring, and the latch retracts into the lock body; after the door is fully closed, the spring force is released, pushing the latch body to extend and insert into the lock hole of the door frame to lock. When opening the door, the handle or lock cylinder drives the connecting rod to move backward, compressing the spring to retract the latch and release the lock.

[0004] The existing latch mechanism has the following drawbacks: the latch body and the connecting rod are separate structures, with the latch body mostly made of plastic and the connecting rod made of metal. The two are connected by welding, bolts or snap-fit, which makes the separate processing and assembly process cumbersome. The connection interface between metal and plastic is prone to loosening or breakage due to stress concentration. It has poor fatigue resistance under long-term high-frequency use, which affects the service life of the door lock. In addition, the connection between the traditional baffle and the connecting rod relies on welding or riveting, which is difficult to disassemble and cumbersome. It is also time-consuming and laborious to replace vulnerable parts such as springs later. Therefore, a latch mechanism for door locks is proposed to address the above problems. Utility Model Content

[0005] To overcome the shortcomings of existing latching mechanisms, a latching mechanism for door locks is proposed.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: The door lock latch mechanism of this utility model includes a latch body, a connecting rod integrally formed on one side of the latch body, a limiting block for axially limiting the connecting rod in the lock body is fitted on the connecting rod, a baffle is assembled on one end of the connecting rod through a convenient disassembly and assembly mechanism, a spring is fitted on the connecting rod, and the two ends of the spring act on one side of the limiting block and the baffle respectively to allow the latch body to extend out of the lock body, and a metal sheath is fitted on the latch body.

[0007] Preferably, the convenient assembly and disassembly mechanism includes an assembly ring, the inner side of which is provided with a limiting protrusion, and an assembly groove formed on the connecting rod to cooperate with the limiting protrusion. The assembly groove includes a rotating part and an entry end for the limiting protrusion to enter the rotating part, and a limiting part for limiting the assembly ring and the connecting rod.

[0008] Preferably, the tongue body is provided with a positioning post, the positioning post is beveled in the assembly direction of the metal sheath, and the metal sheath is provided with a positioning hole that cooperates with the positioning post.

[0009] Preferably, the metal sheath is formed by stamping and bending, and its interface edge is a positioning protrusion. The oblique tongue body is provided with a positioning groove that cooperates with the positioning protrusion.

[0010] The beneficial effects of this utility model are:

[0011] This utility model provides a latch mechanism for a door lock.

[0012] 1. By integrally injection molding the tongue body and connecting rod, the number of parts and connecting components is reduced, material and processing costs are lowered, stress concentration and loosening risks at the metal-plastic interface are eliminated, fatigue resistance is improved, and it is suitable for long-term high-frequency use.

[0013] 2. The convenient assembly and disassembly mechanism utilizes the limit protrusion and the rotating engagement of the assembly slot to achieve quick assembly and disassembly of the baffle through "insertion-rotation-locking" without tools, which greatly improves the efficiency of production assembly and subsequent maintenance.

[0014] 3. The metal sheath forms a reliable mechanical connection with the tongue body through a dual positioning structure of positioning pins and positioning holes, positioning protrusions and positioning grooves. It effectively bears external impact forces, protects the front slope of the tongue from wear, extends service life, and supports individual disassembly and replacement. It has low maintenance costs and the overall structure combines low cost, high reliability and convenient maintenance. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0016] Figure 1 This is an overall structural diagram of the present invention;

[0017] Figure 2 This is an exploded structural diagram of this utility model;

[0018] Legend:

[0019] 1. Slanted tongue body; 2. Connecting rod; 3. Limiting block; 4. Convenient disassembly and assembly mechanism; 401. Assembly ring; 402. Limiting protrusion; 403. Assembly groove; 4031. Rotating part; 4032. Entering end; 4033. Limiting part; 5. Baffle; 6. Spring; 7. Metal sheath; 8. Positioning post; 9. Positioning hole; 10. Positioning protrusion; 11. Positioning groove. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0021] Specific implementation examples are given below.

[0022] Please see Figures 1-2 The present invention discloses a latch mechanism for a door lock, comprising a latch body 1, a connecting rod 2 integrally formed on one side of the latch body 1, the latch body 1 and the connecting rod 2 being integrally injection molded, a limiting block 3 for axially limiting the connecting rod 2 within the lock body being fitted on the connecting rod 2, a baffle 5 being fitted at one end of the connecting rod 2 via a convenient disassembly and assembly mechanism 4, a spring 6 being fitted on the connecting rod 2, the two ends of the spring 6 acting on one side of the limiting block 3 and the baffle 5 respectively, for extending the latch body 1 out of the lock body, and a metal sheath 7 being fitted on the latch body 1.

[0023] The convenient assembly and disassembly mechanism 4 includes an assembly ring 401, with a limiting protrusion 402 on the inner side of the assembly ring 401. It also includes an assembly groove 403 on the connecting rod 2 that mates with the limiting protrusion 402. The assembly groove 403 includes a rotating part 4031 and an entry end 4032 for the limiting protrusion 402 to enter the rotating part 4031. It also includes a limiting part 4033 for limiting the assembly ring 401 and the connecting rod 2. During operation, unlike traditional split structures, this invention uses injection molding to integrally mold the tongue body 1 and the connecting rod 2 into a single piece. The material base is an integral component. The limiting block 3 is fitted onto the connecting rod 2 and cooperates with the inner wall of the lock body to achieve axial limiting of the connecting rod 2. The spring 6 provides a reset force through the baffle 5 connected by the convenient disassembly and assembly mechanism 4, keeping the tongue in the extended state. The convenient disassembly and assembly mechanism utilizes the rotational engagement of the limiting protrusion 402 and the assembly groove 403 to achieve quick loading and unloading of the baffle 5. During assembly and insertion, the baffle 5 is first fitted onto the connecting rod 2, and then the assembly ring 401 is moved axially along the connecting rod 2 so that the limiting protrusion 402 is aligned with the entry end 4032 of the assembly groove. The edge of the entry end 4032 guides the limiting protrusion 402. 2. Move the assembly ring 401 circumferentially, and then rotate it. The limiting protrusion 402 rotates within the groove of the rotating part 4031 to the limiting part 4033 and engages within it. At this point, the limiting protrusion 402 and the limiting part 4033 form a mechanical limit, preventing the assembly ring 401 from axially disengaging. Disassembly is performed by reversing the operation: rotate the assembly ring 401 in the opposite direction to retract the limiting protrusion 402 from the limiting part 4033 back into the rotating part 4031, and then pull it out axially along the entry end 4032. This allows the baffle 5 to be separated from the connecting rod 2. This process requires no tools and is performed entirely by machine. The mechanical structure enables a quick "insertion-rotation-locking" connection. This utility model eliminates the traditional separate processing and assembly process of metal connecting rods and plastic tongues, reducing the number of parts and connecting components, thus lowering material and processing costs. Furthermore, the one-piece molded structure eliminates the risk of stress concentration and loosening at the metal-plastic interface, exhibiting superior fatigue resistance compared to separate structures. It is suitable for long-term, high-frequency use, and the injection molding directly forms the integral structure, reducing overall weight. The absence of subsequent assembly shortens the production cycle and facilitates integration into automated production lines.

[0024] Furthermore, the tongue body 1 is provided with a positioning post 8. The positioning post 8 has a bevel facing the assembly direction of the metal sleeve 7. The metal sleeve 7 has a positioning hole 9 that mates with the positioning post 8. The metal sleeve 7 is formed by stamping and bending, and its interface edge is a positioning protrusion 10. The tongue body 1 has a positioning groove 11 that mates with the positioning protrusion 10. During operation, the metal sleeve 7 is fitted onto the tongue body 1 during assembly. The metal sleeve 7 presses against the positioning post 8. When the positioning hole 9 moves to the positioning post 8, the positioning post 8 is inserted into the positioning hole 9, fixing the metal sleeve 7 to the tongue body 1 to prevent axial pull-out. At the same time as assembly, the positioning protrusion 10 will be embedded. The metal sleeve 7 is inserted into the positioning groove 11 to form a circumferential mechanical interlock, preventing the metal sleeve 7 from rotating around the axis of the tongue body 1, ensuring that the relative position of the metal sleeve 7 and the tongue body 1 is fixed, and a uniform fitting gap of 0.1mm is reserved between the metal sleeve 7 and the tongue body 1. The elastic deformation of the plastic body and the rigid support of the metal sleeve form an elastic pre-tightening force, further enhancing the interface bonding strength; the metal sleeve 7 bears the external impact force and the collision force of the door frame on the tongue when the door is closed. The metal sleeve 7 effectively protects the front slope of the tongue from wear caused by long-term friction, extending the service life of the tongue. In addition, the metal sleeve 7 is assembled by mechanical positioning, without the need for glue or welding, and can be disassembled and replaced separately during maintenance, resulting in low cost.

[0025] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0026] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A latch mechanism for a door lock, comprising a latch body (1), characterized in that: A connecting rod (2) is integrally formed on one side of the tongue body (1). A limiting block (3) is fitted on the connecting rod (2) to axially limit the connecting rod (2) within the lock body. A baffle (5) is fitted on one end of the connecting rod (2) via a convenient disassembly and assembly mechanism (4). A spring (6) is fitted on the connecting rod (2). The two ends of the spring (6) act on one side of the limiting block (3) and the baffle (5) respectively to allow the tongue body (1) to extend out of the lock body. A metal sheath (7) is fitted on the tongue body (1).

2. The latch mechanism of a door lock according to claim 1, characterized in that: The convenient disassembly and assembly mechanism (4) includes an assembly ring (401), with a limiting protrusion (402) provided on the inner side of the assembly ring (401), and an assembly groove (403) formed on the connecting rod (2) to cooperate with the limiting protrusion (402). The assembly groove (403) includes a rotating part (4031), an entry end (4032) for the limiting protrusion (402) to enter the rotating part (4031), and a limiting part (4033) for limiting the assembly ring (401) and the connecting rod (2).

3. The latch mechanism of a door lock according to claim 1, characterized in that: The tongue body (1) is provided with a positioning post (8), the positioning post (8) is beveled in the assembly direction of the metal sheath (7), and the metal sheath (7) is provided with a positioning hole (9) that cooperates with the positioning post (8).

4. The latch mechanism of a door lock according to claim 1, characterized in that: The metal sheath (7) is formed by stamping and bending, and its interface edge is a positioning protrusion (10). The oblique tongue body (1) is provided with a positioning groove (11) that cooperates with the positioning protrusion (10).

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