WO1997021975A1

WO1997021975A1 - Air gun with a gas-driven piston

Info

Publication number: WO1997021975A1
Application number: PCT/CZ1996/000024
Authority: WO
Inventors: Frantisek Vacek; Petr Cech
Original assignee: Frantisek Vacek; Petr Cech
Priority date: 1995-12-13
Filing date: 1996-12-12
Publication date: 1997-06-19
Also published as: CZ282304B6; AU1029197A; CZ328395A3

Abstract

The air gun with a gas-driven piston consists of the body (1), barrel (2), cocking lever (3), piston rod (4) and air piston (5), trigger mechanism (7). The piston rod (4) and the air piston (5) are pushed by the gas piston (8) coming out of the gas cylinder (10) linked via the gas channel (13) with the closed cavity (12) containing the gas bulb (17) which releases the gas through the needle (16).

Description

Air Gun with a Gas-driven Piston

Technical Field

The invention concerns the air gun with a gas-driven piston which consists of a body attached to a barrel, cocking lever which fits into the air piston rod, air inlet under a bullet and trigger mechanism which releases the piston rod and piston.

Background of the Invention

To expel a bullet from the barrel the most common types of air guns employ air compressed by fast movement of a piston placed in a cylinder, by releasing a compressed spring which pushes the piston. The advantage of a compressed spring is relatively stable performance of the air gun which depends on the character of a particular spring. The disadvantage is vibration of the gun which occurs after a shot due to a spring impact. High-quality air guns utilize elimination systems which limit the vibration, however, at the same time reduce gun performance and make the manufacture more costly. Another system used in air guns is the employment of gas bulbs with pressed gas, most often carbon dioxide, which is used for direct expulsion of a bullet from the barrel. The drawbacks of this system are the complexity of gas dosing and high consumption of the gas, with one bulb for cc. 30 - 45 shots. Also the manufacture of this type of air guns is exacting and expensive.

Disclosure of the Invention

The mentioned shortcomings can be eliminated to a major extent in an air gun with a gas-driven piston, which consists of a body attached to a barrel, cocking lever which fits into the air -piston rod, air inlet under a bullet and a trigger mechanism releasing the piston rod and piston. The disclosure of the invention consists in the fact that the piston rod with the air piston are pushed by a gas piston provided with a packing, preferably "O"-ring shaped. The gas piston with the packing is inserted in a gas cylinder which is firmly consolidated in the body and via a gas channel connected with a cavity in a breech piece fixed to the air gun directly in its body or pistol grip. The cavity is designed to accommodate a gas bulb and enclosed with a sealed lid. The cavity contains a needle-injector preferably located on the lid. The advantage of the air gun described herein is its simple design assuring efficient utilization of the gas bulb capacity, reduction of gas consumed for one shot and increase in number of shots per one bulb, with the leakage of gas limited to that through the gas piston packing and the sealed lid. Also the design described herein eliminates any vibrations caused by a spring of other mechanisms. The invention can be used both for air guns and air pistols.

List of Figures in the Drawing

The invention will be described in detail using the drawing with Figure 1, showing a longitudinal section of an air gun designed in compliance with the invention hereunder described herein with an air piston in the forward discharged position and Figure 2 which schematically shows a longitudinal section of an air pistol designed in compliance with the invention hereunder with the air piston in the rearward cocked position and with an inserted bullet.

Examples of the Implemented Invention

The air gun in Figure 1 is an air gun consisting of a cylindrical body 1, attached to a barrel 2 and both these main parts of the gun are attached to a stock 18. The air gun further consists of a cocking lever 3 whose lug 22 fits into an opening in a cylindrical piston rod 4. A front part of the piston rod 4 bears a cylindrical air piston 5 which compresses air to expel a bullet 23 out of the barrel. The air from a space above the air piston 5 is lead under the bullet 23 at the beginning of the barrel 2 through an inlet 6 drilled in a front of the body 1. The air gun also has a lever trigger mechanism 7 which releases the piston rod 4 and the air piston 5 from the cocked position, using a claw 20 which fits into a recess 21 in the piston rod 4. The piston rod 4 with the air piston 5 is pushed with a gas cylindrical piston 8 provided with an "O"-ring shaped packing 9. The gas piston 8 with the packing 9 is inserted in a cylindrical gas cylinder 10, at this air gun type firmly fixed, preferably by being welded or screwed to the breech piece H inserted in the body and connected with its firmly, preferably by a thread. The breech piece ϋ includes a cavity 12 linked via a gas channel ϋ with a space in the gas cylinder 10 under the gas piston 8. The cavity 12 is cylindrical and accommodates a bulb with compressed gas 17, preferably CO,. A needle 16 serves to adjust the gas bulb 17 and release the contained gas. The example in the figure shows the-needle located on a-Md 14 of the cavity 12, the lid provided with a thread and sealing 15, preferably "O"-ring shaped. The air gun in Figure 2 is an air pistol identical with that in Figure 1 , the only exception being the breech piece H with the cavity 12 accommodating the gas bulb H which is located in a pistol grip 19. The breech piece H is connected with the body 1 with a thread and the cavity 12 is linked via the shaped gas channel 13 with the gas cylinder 10.

After inserting the gas bulb 17 into the cavity 12 and closing and tightening the lid 14 by screwing, the air guns shown in Figures 1 and 2 can start shooting since the gas from the gas bulb 12 is released with the needle 16. The gas enters via the channel 13_ into the gas cylinder space under the gas piston 8. After cocking the gun with a cocking lever 3, i. e. pressing the piston rod 4 with the air piston 5 to its rearward position until the claw 20 of the trigger mechanism 7 fits into the recess 21 in the piston rod 4 and keeps it in the rearward position, the gas piston 8 is also pressed to its rearward position. With the bullet 23 inserted in the barrel 2 the air gun is ready to shoot. Pulling the trigger mechanism 7 enables the pressure in the gas cylinder 10 to push the gas piston 8 which shoots out the piston rod 4 and the air piston 5 into the forward position and the compressed air in front of the piston 5 expels the bullet 23 out of the barrel 2.

Industrial Applicability

The air gun design described herein can be utilized both for common air guns or air pistols and for top-quality and high-performance target and hunting air guns, to make their run silent and improve efficiency ofthe gas bulbs utilization.

Claims

PATENT CLAIMS

The air gun with a gas-driven piston made-up by a body attached to a barrel, cocking lever fitting into an air piston rod, air intake under a bullet, trigger mechanism to release the piston rod and the piston with the following typical features: the piston rod (4) with the air piston (5) push the gas piston (8) which is provided with the packing (9) and inserted in the gas cylinder (10) firmly consolidated in the body (1) and linked via the gas channel (13) with the cavity (12) inside the breech piece (11) fixed to the air gun. The cavity (12) is designed to accommodate the gas bulb (17) and closed with the lid (14) with the sealing (15) and it contains the needle (16), preferably located on the lid (14) to adjust the gas bulb (17).