VORRICHTUNG ZUM SIMULIEREN DES KNALLS EINER PLATZPATRONE BEIM SCHIESSEN MIT HANDFEUERWAFFEN

A device for simulating the report effect of a blank cartridge when firing small arms

The present invention relates to a device of the kind defined in the preamble of the following main claim.

Firing blank cartridges is performed at present in the use of small arms by loading the magazine of the weapon with rounds having a propulsion charge but no bullet. Manufacturing, transport handling and storing of the blank cartridges result in costs which can amount to a considerable sum per year. The object of the present invention is therefore to provide a device which makes it possible to provide the desired report effects of blank cartridges when firing small arms in a way such that the costs for firing with blank cartridges is considerably reduced in relation to the above mentioned costs.

This is achieved with a device working with a compress- ed gas such as compressed air, the device in accordance with the invention having the characterizing features defined in the following claims.

In the inventive device there is thus a housing which is fitted to the weapon instead of the ordinary cart¬ ridge magazine, the housing containing a first valve which can be coupled to the trigger of the weapon via a link system. In the housing there is a compressed air container in the form of a chamber provided with a nipple, to which a hand-driven pump may be connected for charging the container with compressed air. Alter¬ natively, an exchangeable container may be used, which is charged beforehand with the aid of a stationary compressed air source. When the trigger is activated, communication between the compressed air container and a dosing chamber is closed with the aid of a first valve, a second valve being simultaneously activated to open the outlet from the dosing chamber, from which a predetermined quantity of compressed air flows out to the atmosphere with a report. When the trigger is re¬ leased and returned to the rest position, the dosing chamber will be recharged.

A suitable embodiment of the device in accordance with the invention is shown as an example on the accompany¬ ing drawing.

Fig 1 is a section through a device in accordance with the invention, taken along the line 1-1 in Fig 2, Fig 2 is a view of the device seen from the front, and Fig 3 illustrates the valves in a position corresponding to completely depressed trigger for letting out a quantity of compressed air with a report effect.

In the Figures there is shown a housing 10 with approx¬ imately the same size and shape as a conventional cart- ridge magazine for a weapon such as an automatic carbine. This housing can be fitted to the weapon in¬ stead of the cartridge magazine.

In the housing there is a compressed air chamber 11 which, via a nipple 12 and non-return valve, can be filled with a pressurized gas such as compressed air with the aid of a hand-operated pump or in some other way.

In the housing there is also a cylindrical dosing chamber 13 which, with the aid of an axially movable piston disc 14, is divided into an inlet chamber 13A and an outlet chamber 13B. The piston disc is provided at its edge with a lip sealing 14A, functioning as a one-way valve for the stream of compressed air from the chamber 13A to -the chamber 13B when the chamber 13A is filled with compressed air, but which prevents flow back in the opposite direction.

A valve housing 15 is also included in the device, and has a slide valve 16 in the form of a plunger which is movable between two end positions to form a first valve in the device.

The piston disc 14 coacts with a seat 17 at the inlet end of a throat forming an outlet 18 from the outlet chamber 13 of the compressed air chamber, the piston disc functioning as a second valve in the device.

The slide valve 16 has an annular groove 19 which, in the open position of the valve shown in Fig 1 , opens the communication between a radial channel 20 from the chamber 11 to a channel 21 leading the compressed air to the inlet chamber 13A, the piston disc 14 then being pressed against the seat 17 to close the outlet 18. The supplied compressed air flows past the elastic lip 14A to charge the outlet chamber 13B, the volume of which in the illustrated example determines the predetermined quantity of compressed air which is to be released through the outlet.

In Fig 1, the slide valve 16 is in its inner position and is kept in this position by a compression spring 22. Since the gas forces on the slide valve are balanced out in the annular groove 19, the spring 22 can be relatively weak, and this is an advantage, taking into account that the resistance to withdrawal of the slide valve to its outward end position in Fig 3 should not be greater than the position in Fig 3 being enabled with ordinary pressure on the trigger. Between a hole 23 in the outer end of the slide valve and an unillu- strated trigger of a small arms weapon there is a link mechanism for translating the motion of the trigger to the slide valve.

OMPI When motion of the slide valve 16 from the position in Fig 1 towards the end position in Fig 3 is initiated, nothing happens as long as the groove 19 has communica¬ tion with the channel 21. The forward portion of the slide valve will close off the channel 21 in a given position and for continued withdrawal there is achieved an intermediate position where the inner end of the slide valve has passed the opening of the channel 21 so that the channel opens freely into the bottom chamber 23, formed between the inner end of the slide valve and the bottom of the bore for the slide valve mounting. This chamber communicates in turn with a central channel 24 in the slide valve, the central channel accordingly being connected to the atmosphere via a hole 25 when the slide valve is in its utmost position according to Fig 3.

In said intermediate position for the slide valve, there is provided a momentary emptying of the inlet chamber 13A, in turn resulting in that the compressed air in the chamber 13B urges the piston disc 14 back again towards its open position in Fig 3, and the compressed air in the chamber 13B streams out through the throat 18 to expand with a report.

The intermediate position described thus corresponds to the pressure point for pulling the trigger which is to be found in most small arms, triggering for an air report will thus take place with the same feeling as for triggering an ordinary shot.

From the intermediate position, compressed air in the chamber 23 takes over the continued displacement of the slide valve to its utmost position, and as soon as both chambers 13A and 13B have been emptied, the spring 22 will urge the slide valve 16 back into its inward posi¬ tion according to Fig 1 for once again filling the

OM chambers 13A and 13B with compressed air.

* There is a hub 26 carried by a plurality of spokes 26A in the throat 18. A -shaft 26B is displaceably mounted 5 in the hub 26 and carries at its* inner end a valve plunger 27 forming a third valve. In its closed posi¬ tion the plunger is disposed, according to Fig 1 , in a bore 28 partially filled by the plunger but leaving a small chamber 29 free in the closed position. The 10 valve plunger is kept in its closed position by a compression spring 26C which is biased between the hub and plunger.

When the piston disc 14 is open, the chamber 29 is 15 filled first until the pressure in it is sufficiently large to displace the plunger 27 to its open position in Fig 3, where the compressed air streams past the plunger in an expanded portion 18A of the throat, past the spokes 26A and out through the funnel-shaped outlet 20 end 30 of the outlet, this funnel being formed to give the best possible report effect during the expansion of the compressed air.

The illustrated device can be charged to fire about 25 20 shots, after which the housing 10 can be replaced by a housing with a charged chamber 11, or the chamber 11 can be filled with air to a desired pressure with the aid of a hand pump.

30 It will be seen from the above that the cost of firing an "air shot" will be several times less than the cost of firing a shot with blank cartridges.

The weight of the weapon will be approximately the same 35 as for an ordinary cartridge magazine, but the need for carrying a supply of blank cartridges is avoided. The extra weight from a small hand pump is not troublesome.