DE29703824U1 - Firearm with a gas pressure absorber - Google Patents

Description

JLEINWEBER &&idigr; ZIMMERMANN

EUROPEAN PATENT ATTORNEYS

Dipl.-Ing. H. Leinweber (19761)
Dipl.-Ing. Heinz Zimmermann
DipL-lng. A. Gf. v. Wengersky
Dipl.-Phys. Dr. Jürgen Kraus
Dipl.-Ing. Thomas Busch

PATENT ATTORNEYS

Rosental 7,

D -80331 Munich

TEL (089) 231124-0
Fax (089) 231124-11
TLX 528191 LZPATD

³ March 1997

Our sign

wysd
JG Anschütz GmbH, 89079 Ulm

Firearm with a gas pressure absorber

The invention relates to a firearm, in particular an air rifle with a gas pressure absorber, which consists of a gas cylinder with a piston running in it, which is acted upon in the direction of its front end position in the gas cylinder by a spring accumulator, which is charged under the gas pressure of the shot when the piston moves backwards.

Such a firearm is already known (DE 27 50 Al). In the known firearm, the gas pressure is diverted into the gas pressure absorber when a cartridge is fired. The gas pressure absorber is arranged parallel to the barrel, but offset to the side. This creates an additional lateral impulse when the piston in the gas cylinder of the gas pressure absorber moves back. The same applies to similar designs in known air rifles.

The object of the invention is to propose such an absorber in which the lateral impulse is avoided and the functional sequence of the gas pressure absorber is optimized. The solution to this object is characterized in the claims.

It can be seen that by attaching the gas cylinder in line with the barrel axis, the lateral impulse of this additional device is eliminated. This minimizes interactions between the function of the gas pressure absorber and the weapon. The achievable shooting precision is increased. This plays a particularly important role in competition weapons.

The gas pressure absorber is made up of a guide sleeve attached to the rear of the locking slide and an absorber bolt running in it.

A compression spring is used as a spring accumulator between the rear cylinder bolt of the gas cylinder and the piston. The spring constant and length of the spring can be used to influence the return behavior of the absorber bolt, which serves as the piston. If desired, it is also possible to use the compression spring to return the absorber bolt to its original position after the shot has been fired.

Another way of influencing the movement behavior of the piston is to vent the gas cylinder. To do this, a vent hole with a large cross-section is provided at the rear end of the guide sleeve, thus ensuring that no pressure cushion builds up behind the piston that would hinder its return. On the other hand, a vent hole with a smaller cross-section is provided at the front end of the guide sleeve, through which the pressure cushion at the front end of the piston is only gradually reduced as the piston returns, thus reducing the return speed.

At the same time, however, it is of course necessary to ensure that the piston return is not obstructed by negative pressure at its

front end. This is done by providing the guide rings of the absorber bolt with clearances at both ends, which allow air to pass from the rear to the front end. Of course, the large cross-section vent opening, the small cross-section vent hole and the clearances must be coordinated with one another in such a way that the desired movement behavior of the piston during return and when returning to the starting position is guaranteed.

The previously explained compression spring and the piston guides also play a role, which can additionally influence the movement behavior when designed as a friction ring. The specialist therefore has numerous options available to him with which he can influence the movement behavior of the gas pressure absorber, which is aligned with the barrel axis, and give it the characteristics desired for the respective application.

Another possibility is to use an intermediate bolt between the barrel root and the front end of the absorber bolt to actuate the bolt. The diameter of the intermediate bolt should ideally extend right up to the gas supply opening behind the barrel root. This means that there are no unnecessary gas losses, particularly in air rifles. The arrangement of the gas cylinder in line with the barrel axis ensures a very high level of effectiveness.

Instead of returning the absorber bolt using the compression spring inserted between it and the rear base of the gas cylinder, forced return using the locking slide and/or coupled with the tensioning lever actuation is also possible.

In the drawing, the invention is illustrated by way of example and the figure shows partially torn open and

in section an embodiment of the invention on an air rifle.

A locking slide 12 is connected to the barrel root 10 in an axially movable manner, in which a guide sleeve 14 serving as a gas cylinder of the gas pressure absorber is fastened at the rear in alignment with the barrel axis, in the free interior of which an absorber bolt 16 is arranged in an axially movable manner.

The absorber bolt 16 has a slightly smaller diameter than the guide sleeve 14. At its front end it has a guide ring 18 with sealing lips 20 which elastically rest against the inner wall of the guide sleeve 14." At its rear end the absorber bolt 16 has a friction ring 22 with clearances which, when the absorber bolt 16 returns, allow ventilation of the space at the front end of the guide sleeve 14 via the clearances in the friction ring 22 and the sealing lips 20, so that the movement of the absorber bolt 16 is not hindered by negative pressure at the front end of the guide sleeve 14.

A compression spring 24 is inserted between the rear end of the absorber bolt 16 and the rear cylinder base of the guide sleeve 14. Furthermore, a large diameter vent opening 26 is provided at the rear end of the guide sleeve, which breaks through the cylinder wall of the guide sleeve 14 to the outside and prevents a pressure cushion from building up in the guide sleeve 14 when the absorber bolt 16 returns.

At the front end of the guide sleeve 14 there is a vent hole 28 of much smaller diameter, which ensures an additional supply of air into the vacuum chamber at the front end of the guide sleeve when the absorber bolt 16 returns, but only ensures a gradual discharge of the pressure when the absorber bolt 16 is returned to its starting position, so that the return speed of the absorber bolt 16 is reduced.

The absorber bolt 16 is not actuated directly by the gas pressure, but via an intermediate bolt 30. This can also be aligned with the barrel axis or, as in the example shown, is arranged slightly offset to the side from the barrel axis and the axis of the absorber bolt 16. However, it is crucial that the diameter of the intermediate bolt 30 corresponds to the diameter of the projectile. The intermediate bolt 13, which serves as the actuator, and the projectile base are therefore subject to an equal driving force. The intermediate bolt 30 thus significantly increases the effectiveness of the gas pressure absorber. The intermediate bolt 30 runs smoothly in a hole provided for it in the breech slide 12, but due to its length it does not need to be set up and returned to its original position. Rather, it is returned to its original position by the absorber bolt 16 itself {cf. the position in the figure) when the absorber bolt 16 reaches its right end position shown in the figure. In this position, the intermediate bolt 30 is supported by a head 32 on the front cylinder base of the guide sleeve 14 because the head 32 has a larger diameter than the shaft of the intermediate bolt 30.

When the shot is fired, a valve 36 is opened by actuating the firing pin 34, which builds up the gas pressure in a chamber 40 behind the barrel root via a cross hole 38 positioned accordingly in the bolt 12. This means that the absorber bolt 16 is moved simultaneously with the projectile expelled through the barrel, but in the opposite direction to it, via the intermediate bolt 30.

List of reference symbols

10 Barrel root 12 Locking slide 14 Guide sleeve 16 Absorber bolt 18 Guide rings 20 Sealing lip 22 Friction ring 24 Pressure spring 26 Vent opening 28 Vent hole 30 Intermediate bolt 32 Head

34 Impact piece 3 6 Valve 38 Cross hole 40 Chamber

Claims (10)

Expectations : 1. Firearm, in particular an air rifle, with a gas pressure absorber, which consists of a gas cylinder with a piston running in it, which is acted upon in the direction of its front end position in the gas cylinder by a spring accumulator, which is charged during the backward movement of the piston under the gas pressure of the shot, characterized in that the gas cylinder (14) is arranged in alignment with the barrel axis. 2. Firearm according to claim 1, characterized in that the gas cylinder is designed as a guide sleeve (14) for an absorber bolt (16) serving as a piston. 3. Firearm according to claim 1 or 2, characterized in that the spring accumulator is a compression spring (24) inserted between the rear cylinder base of the guide sleeve (14) and the absorber bolt (16). 4. Firearm according to one of claims 2 or 3, characterized in that a vent opening (26) with a large cross-section is provided at the rear end of the guide sleeve (14) and a vent hole (28) with a small cross-section is provided at the front end of the guide sleeve. 5. Firearm according to one of claims 2 to 4, characterized in that for the reduction of the negative pressure on the front side of the absorber bolt (16) clearances are provided in guide rings (18, 22) at its two ends. 6. Firearm according to one of claims 2 to 5, characterized in that at least one of the guide rings of the absorber bolt (16) is designed as a friction ring (22). 7. Firearm according to one of claims 2 to 6, characterized in that between the barrel root (10) and the front end of the absorber bolt (16) as an actuator for the latter an intermediate bolt (30) is inserted, the diameter of which corresponds to the bullet diameter. 8. Firearm according to claim 7, characterized in that the tappet of the intermediate bolt (30) extends directly to the gas supply opening (38) behind the barrel root (10). 9. Firearm according to one of claims 2 to 8, characterized in that a forced return of the absorber bolt (16) is provided by means of the locking slide (12). 10. Firearm according to one of claims 2 to 9, characterized in that the forced return of the absorber bolt (16) to its starting position takes place via a cocking lever actuation.