EP4544255A1

EP4544255A1 - Assembly of a receiver and a forearm

Info

Publication number: EP4544255A1
Application number: EP23734895.8A
Authority: EP
Inventors: Vladimir Simek
Original assignee: Ceska Zbrojovka AS
Current assignee: Ceska Zbrojovka AS
Priority date: 2022-06-22
Filing date: 2023-06-15
Publication date: 2025-04-30
Also published as: WO2023246959A1; CZ2022281A3

Abstract

An assembly of a receiver (1 ) and a forearm (2) wherein the forearm (2) is attached to the receiver (1) in a dismountable manner. The forearm (2) is fixed by means of a latch (3). The latch (3) consists of a rocker-arm lever and is mounted in the receiver (1 ) on a pin (5) wherein at one end, the latch (3) is fitted with a nose (9) adapted to engage into the corresponding recess (10) in the forearm (2). The latch (3) is biased towards the recess (10) by a spring (6). The latch (3) is equipped with a pair of side protrusions (11) that laterally project from the forearm (2).

Description

Assembly of a receiver and a forearm

Technical field The invention relates to an assembly of a receiver and a forearm, the forearm being attached to the receiver in a dismountable manner and the forearm being fixed by means of a latch.

Background art

Maintenance and cleaning of a firearm sometimes require the forearm to be separated from the receiver of the firearm. Thus, the forearm is usually atached to the receiver by means of a latch, pins or screws. A disadvantage of such designs is that the joint is predetermined either as dismountable without the use of tools, or fixed that requires tools to be dismounted. A joint that is dismountable without the use of tools exhibits lower resistance of the joint and a play in the joint and the user does not have the possibility to delimit this joint or to add a pin or screw to the joint to increase its resistance later on. On the other hand, a fixed joint requiring tools for its release does not provide the user with the possibility of a quick replacement of the forearm or disassembly during the maintenance of the firearm. The latches or pins for the disassembly of the firearm without the use of tools are then only accessible from one side of the firearm, which may impair their accessibility if the firearm is fited with accessories. The joint that is dismountable without the use of tools is exposed to the risk of being released in case of a fall of the firearm.

Thus, it is the object of the invention to provide such a design of the assembly of the receiver and forearm that would eliminate the shortcomings of the prior art.

Summary of the invention The said object is achieved by an assembly of a receiver and a forearm wherein the forearm is attached to the receiver in a dismountable manner and the forearm is fixed by means of a latch, according to the invention the principle of which is that the latch consists of a rocker-arm lever and is mounted in the receiver on a pin. At one end, the latch is fitted with a nose, adapted to engage into the respective recess in the forearm and the latch is biased by a spring towards the recess. The latch is equipped with a pair of side protrusions that laterally project from the forearm.

In a preferred embodiment, the latch comprises a threaded opening to insert a locking screw.

The inventive solution enables control from the left as well as right side of the firearm, in addition, the joint is dismountable without the use of tools and after a simple installation of the locking screw, it can be simply adapted to a joint requiring the use of tools if the user decides to use a fixed joint of the receiver and forearm later on.

To prevent inadvertent unlocking of the latch, the second arm of the latch, averted from the arm with the nose, may be adapted to bear on the front part of the charging handle assembly.

Brief Description of Drawings

The invention will be described in more detail with reference to particular embodiment examples of the inventive assembly of the receiver and forearm, shown in the attached drawings where individual figures represent:

Fig. 1 - an embodiment example of the assembly of the receiver and forearm with the latch without the locking screw;

Fig. 2 - a detail of the embodiment of Fig. 1 ;

Fig. 3 - a detail of the embodiment of Fig. 1 where the latch is fixed with a locking screw; Fig. 4 - a top view of the embodiment of Fig. 3 wherein the receiver and the forearm are shown in a sectional view;

Fig. 5 - a top view of the embodiment of Fig. 3:

Fig. 6 - the embodiment of Fig. 1 with the forearm partly removed.

Examples of Embodiments

In the assembly of the receiver 1 and the forearm 2 according to Figs. 1 and 2, the forearm 2 is mounted on a guide on the receiver 1 (see Fig. 6) and fixed with a latch 3.

The latch 3 consists of a rocker-arm lever that is mounted in the receiver 1 in a swinging way on a pin 5. At one end, the latch 3 has a nose 9, adapted to engage into the corresponding recess 10 on the inner side of the forearm 2.

The latch 3 is biased towards the recess 10 by a spring 6. The latch 3 is fitted with a pair of side protrusions 11 that laterally project from the forearm 2 so that the shooter may press them with his/her right or left hand downwards. When the latch 3 has been pressed, the forearm can be slid forwards to be removed from the receiver 1 (see Fig. 6).

In the latch 3, a through threaded opening is vertically arranged, which is closed with a cap 4 at the top side in Fig. 2. After the removal of the cap 4, a locking screw 8 can be screwed into the threaded opening (see Fig. 3) that will block the movement of the latch 3 so that the nose 9 of the latch 3 is permanently engaged in the recess 10 and the forearm cannot be dismounted.

To prevent inadvertent unlocking of the latch 3, the second arm of the latch 3, averted from the arm with the nose 9, is adapted to bear on the front part of the assembly of the charging handle 7.

To disassemble of the forearm 2, the charging handle 7 must be first moved from the front position rearwards to unlock the latch 3 and if no locking screw 8 is installed, all that needs to be done Is to press one of the side protrusions 11 downwards to disengage the nose 9 of the latch 3 from the recess 10 in the downward direction. Then, the forearm can be removed from the receiver 1 . During the installation of the forearm 2 onto the receiver 1 , the leading surface at the front of the nose 9 will ensure compression of the latch 3 together with the spring 6 and subsequent engagement of the nose 9 into the recess 10, which will fix the forearm 2 on the receiver 1. List of reference signs

1 receiver

2 forearm

3 latch

4 cap 5 pin

6 spring

7 charging handle

8 screw

9 nose 10 recess

11 side protrusion

Claims

1. An assembly of a receiver (1) and a forearm (2) wherein the forearm (2) is attached to the receiver (1) in a dismountable manner and the forearm (2) is fixed by means of a latch (3), characterized in that the latch (3) consists of a rocker-arm lever and is mounted in the receiver (1) on a pin (5) wherein at one end, the latch (3) is fitted with a nose (9) adapted to engage into the corresponding recess (10) in the forearm (2), and the latch (3) is biased towards the recess (10) by a spring (6), and the latch (3) is equipped with a pair of side protrusions (11 ) that laterally project from the forearm (2).

2. The assembly according to claim 1 , characterized in that in the latch (3) a threaded opening is arranged to install a locking screw (8).

3. The assembly according to claim 1 or 2, characterized in that the second arm of the latch (3), averted from the arm with the nose (9), is adapted to bear on the front part of the charging handle (7) assembly.