DE3434754A1 - AIR COMPRESSION SYSTEM FOR AIR ARMS - Google Patents

Description

Air compression system for compressed air guns, especially air rifles, and compressed air gun, especially air rifle

The invention relates to an air compression system for compressed air guns, in particular air rifles, of the type specified in the preamble of claims 1 or 3, furthermore to a compressed air gun, in particular an air rifle of the type specified in the preamble of claims 5 or 8.

According to the respective fire mechanism, a distinction is made between three Types of air guns, namely pump type air guns, gas operated air guns, and spring type air guns. The invention is concerned deal with the further development of the latter type of air rifle.

In many spring-type air rifles, a steel cylinder, which normally about 3 cm in diameter and about 35 cm in length, constitutes the basic element of the fire mechanism. The Barrel is hinged to the front of the steel cylinder so that the loading chamber can be opened, with a clamping mechanism on a massive steel cylinder sliding. Piston acts to move the piston rearward and compress a fire coil spring. The fire mechanism is by a trigger mechanism in the rear position; of the piston, in which the fire coil spring is fully compressed is. After inserting a projectile into the loading chamber and closing it, the air rifle is ready to fire. By pulling the

^ O trigger, the latched fire mechanism is released, so that the piston moved forward at high speed by the fire coil spring and the air in the steel cylinder in front of the piston is increasingly compressed is until the air pressure reaches a limit at which the bullet propelled at high speed along the barrel and is pushed out of the barrel.

The average shooter consumes when using one Air rifle for target shooting and / or for hunting, for example from

Rabbits, pests, and birds, such as pigeons, between 4,000 and 6,000 0-5 storeys a year. With a new air rifle, the first thing to do is zero in required for sight adjustment, consuming up to about 500 projectiles. The shooter also determines during zeroing in, what type of bullet he wants to use, which can also make changes to the sight setting necessary because of different bullet weights and configurations can influence the projectile speed.

With a new air rifle with a new fire coil spring, shooting in can have different effects. First of all, the other moving parts of the air rifle begin to run in,

1-5 for example. The piston seals can work themselves slightly free, which results in an increase in the speed of the projectile. This will be carried out during the first period of use of the new air rifle compensated for the drop in the force of the mechanical fire coil spring, which can always be observed, even during the first 500 to 1000 shots. For example, for an air rifle with an energy level just below 16.27 3 (= 12 ft lbs) at the muzzle, the maximum limit for gun license-free air rifles in Great Britain, the behavior can drop by as much as 5 to 10%, related to the energy peak value. Although has continued use

2-5 of the air rifle did not deteriorate as quickly after this initial period of the behavior, however, there is a further, only gradual but steady deterioration of the fire coil spring behavior to observe.

The coil springs of these air rifles are generally made from high quality round steel wire which has been previously hardened and quenched, and after the spring has been coiled, it has been de-stressed for several hours at low temperatures prior to testing is made. When such coil springs are compressed,

then the energy is actually released by the twisting spring wire stored, but it is well known that several thousand times repeated compression and release of these coil springs a decrease in the spring behavior has the consequence, primarily as a result of a reduction in the spring length, for example due to Impairment of the entire helical spring with a corresponding change in the pitch of the coils or due to local exhaustion a few turns.

The shooter can counteract this gradual deterioration by readjusting the sights counteract to some extent. Although this can be satisfactory for shooting at stationary targets over short distances, however, even if the performance has deteriorated considerably, the sharp decrease in performance due to the shortening of the Fire coil spring considerably increases the use of the air rifle in hunting where the distances from the target can be considerably greater.

Because of these well-known difficulties associated with helical fire springs, experienced shooters change the helical fire spring in air rifles of the type in question, for example at the beginning of a shooting season. Protect, which shoot a lot, the fire coil spring even change regularly, for example, every three months, which is time consuming and expensive, not to mention the ^gradual: lent performance degradation even during this three-month periods.

It is well known that shooters prefer to hunt with air rifles The type in question, to keep the air rifle cocked so that it can be fired immediately, the air rifle being relatively can be in a tensioned state for a long time, for example over half an hour or even longer, which if it happens regularly, the Effectiveness of the fire coil spring impaired very quickly and at an early stage. Therefore, the shooter releases the main coil spring of the air rifle,

so that it is not ready to fire more often than he actually is at the Hunt wishes. There is therefore also a need for an air rifle which can be used in any way without releasing the action of the fire coil spring can stay excited for a long time.

Finally, the problem is with air rifles of the type in question it is not uncommon for the fire coil spring to break, for example due to improper hardening or quenching of the wire Tensile strength from which the fire coil spring is made.

These well-known difficulties with helical compression air rifles as an energy source for firing the projectile have long had the need for a more consistent and long-lasting energy source let arise. A gas-operated air rifle has therefore already been developed (GB-PS 20 84 704), which is far superior to its predecessors is and has found widespread use. This very successful air rifle is with a single gas spring to generate that air pressure provided, which is required to fire the respective projectile.

The conventional helical compression spring is used in this gas-operated air rifle replaced by a gas spring, which provides various advantages, in particular a quick and consistently good functionality. However, the rapid forward movement of the hollow piston of the single gas spring causes considerable damage when the air rifle is fired Recoil, which is not uncommon with air rifles, however Can cause inaccuracies.

It is known the adverse effects of recoil thereby to counteract that two helical compression spring-driven pistons are provided which counteract each other horizontally (GB-PS 803 028). The two pistons are mechanically connected to one another by a rack and pinion mechanism, which ensures that they are in the same

Extent to be accelerated towards each other. The pistons should be the same Have masses so that the inertial forces due to the movement and stoppage of each piston are substantially equal and each other annihilate each other because they are opposed to each other. Since it is practically impossible to put one between the two helical compression springs To achieve force compensation, which is due, for example, to manufacturing lungs difficulties or due to it is not possible because the spring forces the helical compression springs fall off at different speeds, it is inevitable that there is always a helical compression spring above the toothed racks / Pinion mechanism also drives the opposite piston. This driving power transmission at high speed via the rack and pinion / pinion mechanism can lead to wear and tear and even failure of the mechanism.

The object of the invention is to address the disadvantages of the above To avoid compressed air guns and to ensure all the advantages of the gas-operated compressed air guns essentially without recoil reliably. An essentially recoil-free compressed air gun is also to be created which has a simple mechanical structure and easy to assemble, repair and maintain.

This task is due in the characterizing part of the claim 1 or 3 or 5 or δ specified features solved. Advantageous refinements of the invention are set out in the remaining claims specified.

Below is an embodiment of the invention with reference to drawings for example described. It shows schematically:

FIG. 1 shows a longitudinal section of the air compression system of an air rifle in the cocked state;
35

FIG. IA shows the tensioning mechanism return spring; 05

Figure IB the part of the longitudinal section according to Figure 1 in the area of the loading chamber on a larger scale;

Figure 2 is a partially broken away bottom view of the air compression system according to Figure 1, with parts of the clamping mechanism

are omitted;

FIG. 3 shows the longitudinal section according to FIG. 1, the air compression system is in the state after a shot has been fired;

FIG. 4 shows the view from below of the air compression system according to FIG 3; and

FIG. 5 shows a longitudinal section of a connection of the compensation duct of the air compression system according to FIGS. 1 to 4.

The rifle shown comprises an optionally rifled barrel 38, a shaft having a running support 56, and an outer main cylinder ■ yc 10 beneath the barrel 38, which belongs to the air compression system with two opposing gas springs of the air gun.

The rear end of the bore 38A of the barrel 38 merges into a loading chamber 36 into which a projectile 37 is inserted by means of a loading bolt 55. Instead, it is also possible to insert the projectile 37 into the loading chamber 36 in that the barrel 38 is pivoted with respect to the shaft.

In the master cylinder 10 are a front hollow piston 16 and a rear one Hollow piston 18 is axially displaceable, each of which is received by means of an annular groove 17A of the piston head 16A or 18A

O-ring 17 are sealed against the master cylinder 10 and with O ^ the opposing piston heads 16A and 18A an air compression chamber 32 in the master cylinder 10.

In the middle of the air compression chamber 32, a leads radially outward running connecting channel 34 into the loading chamber 36, which opens there immediately behind the projectile 37, so that the same when firing of the air rifle is driven along the bore 38A of the barrel 38, namely when the approaching each other at high speed two hollow pistons 16 and 18 compress the air in the air compression chamber 32 to a high pressure and the air pressure at the loading chamber 36 exceeds a predetermined limit value.

The two hollow pistons 16 and 18 each belong to a front or rear gas spring, which further comprises an inner cylinder 12 or 14, which is arranged stationary in the front or rear end of the master cylinder 10 and has a closed front end 20 or at the rear The end is closed by an end piece 22 with a gas introduction channel 24 sealed by means of a grub screw. The latter is a valve 58 assigned, via which gas can be fed under high pressure into the rear inner cylinder 14, which also into the front Inner cylinder 12 arrives to fill the front gas spring in the master cylinder 10, as will be described.

The two inner cylinders 12 and 14 are with the opposite, open ends each received in the bore of the front hollow piston 16 or in the bore of the rear hollow piston 18 telescopically and for sealing against the associated hollow piston 16 or 18 at the end protruding into the same with an O-ring 26 and a Lip seal ring 27 is provided. The two lip seals 27 are each arranged in an annular groove at the protruding end of a short tube 29, which in the open end of the front or rear inner cylinder 12 or 14 by gluing, for example by means of the under the

Trade name "Loctite" known adhesive, is attached, and are respectively undercut on the inside of the associated hollow piston 16 or 18 facing side, so that when pressurized gas in the front and the rear gas spring is filled, the pressure of this gas the circumferential lip of the one lip sealing ring 27 as well as that of the other lip sealing ring 27 against the bore surface of the hollow piston 16 or 18 presses. There are two sealed gas expansion chambers 28 and 30 in the main cylinder 10, which are connected to the front and rear gas springs belong.

In Figure 1, the two hollow pistons 16 and 18 are retracted, tense Position shown, wherein the air compression chamber 32 has its largest volume. The two inner cylinders 12 and 14 each have in the area protruding into the associated hollow piston 16 or 18, a reduced outer diameter, so that in this area between the inner cylinder 12 or 14 and the master cylinder 10 an annular space for receiving the open end of the hollow piston 16 or 18 located in the retracted position according to FIG.

For tensioning, each hollow piston 16 or 18 is provided with a radially outward one protruding pin 21 is provided, which is connected to a floating shoe 42, which in turn is mounted on a rack 44. The two racks 44 mesh at the ends facing away from the two shoes 42 with a common central pinion 46, which sits on a bearing which can be attached to the outside of the master cylinder 10 or to another part of the stock of the air rifle.

So that the two racks 44 and pin 21 are displaced longitudinally can, the master cylinder 10 is provided with two longitudinal slots 21A, which, however, only extend so far towards each other that they are in the retracted position of the two hollow pistons 16 and 18 according to Figure 1 does not protrude beyond the piston heads 16A and 18A to the Integrity of the air compression chamber 32 is not compromised.

The two racks 44 meshing with the pinion 46 have the effect that the two hollow pistons 16 and 18 can only move in opposite directions to one another by the same distances. The tensioning takes place with the help of a tensioning lever 48 and a pawl 50 with a nose 50A, which protrudes through a longitudinal slot 50B in the master cylinder 10 and falls into an outer recess 52 at the rear end of the rear hollow piston 18, around the same in the retracted position according to FIG to keep. The front hollow piston 16 is held in the retracted position according to FIG. 1 via the two toothed racks 44 and the pinion 46, which connect it to the rear hollow piston 18.

When the two hollow pistons 16 and 18 are moved apart into the position according to FIG are, then the previously filled in the two gas expansion chambers 28 and 30 pressurized gas is compressed even further, so that the air rifle is cocked and ready to fire when the projectile 37 has been inserted into the loading chamber 36 beforehand.

According to Figure 2, the two inner cylinders 12 and 14 by one of a compensation channel formed on the outside of the master cylinder 10 running along the pipe 31 directly connected to one another, so that gas pressure equalization takes place between the two gas expansion chambers 28 and 30 can. FIG. 5 illustrates the connection of the two ends of the compensation channel 31 by means of one each sealed in a fastening pin 31B, radial connecting pipe 31A through the master cylinder 10 the interior of the front inner cylinder 12 or to the interior

of the rear inner cylinder 14.
30th

When the trigger of the air rifle is pulled and the pawl 50 is pivoted to release the rear hollow piston 18, the two hollow pistons 16 and 18 are driven towards each other at the same speed due to the gas pressure equality in the two gas expansion chambers 28 and 30 ensured by the equalization channel 31

to cause a high compression of the air in the air compression chamber 32, which reaches the loading chamber 36 via the connecting duct 34, so that the projectile 37 is propelled forward in the barrel 38 at high speed. According to FIG. 1B, the connecting channel 34 is sealed off from the open atmosphere by means of a front O-ring 53 and a rear O-ring 54, which enclose the barrel 38, while the latter is tightly closed at the rear end by the loading bolt 55 and an O-ring 57 is.

The two racks 44 and the pinion 46, which the two hollow pistons 16 and 18 mechanically connect to one another, do not need to transmit any forces between the hollow pistons 16 and 18 when firing, because the gas pressures in the two gas expansion chambers 28 and 30 are balanced via the compensation channel 31. Although the racks 44 and move the pinion 46 when firing at high speed, this does not result in any wear, because they are unloaded.

Even if in the illustrated and described embodiment, the both hollow pistons 16 and 18 have the same dimensions and masses, the invention can nevertheless be used to balance forces in any piston can be used, especially in connection with two pistons acting against one another, one of which is smaller, lighter and faster and the other is bigger, heavier and slower.

Αζ

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Claims (1)

Claims 1. Air compression system for compressed air guns, in particular air rifles, with several pistons arranged essentially without recoil for compressing air in one Air compression chamber for firing a projectile, characterized in that each piston (16; 18) has a movable element of its own gas spring is integrated or connected, each of which contains a gas expansion chamber (28; 30) for receiving pressurized gas and each gas expansion chamber (28; 30) with at least one other gas expansion chamber (30 ^ 28) for constant gas pressure equalization connected or connectable. 2. Air compression system for air guns, in particular Air rifles, with multiple pistons for compressing air in an air compression chamber for firing Projectile, characterized in that each piston (16; 18) with a movable element one own gas spring is integrated or connected, each of which has a gas expansion chamber (28; 30) for receiving compressed gas and each gas expansion chamber (28; 30) with at least Radedcestraße 43 8000 Munich 60 Telephone (0S9) 883603/833604 Telex 5212313 Telegrams Patentconsult Another gas expansion chamber (30; 28) is connected or connectable for constant gas pressure equalization, wherein the Pistons (16; 18) and gas springs are arranged in such a way that the resultant of the forces as a result of the movement each piston (16; 18) is substantially zero. 3. Air compression system according to claim 1 or 2, characterized in that each piston (16; 18) * is arranged in such a way that there is air in the air compression chamber when firing (32) compressed. 4. Compressed air gun, in particular air rifle, in which a projectile is essentially recoil-free by means of compressed air is driven out of the barrel, which has been compressed in an air compression chamber, characterized in that several gas springs with one movable piston (16; 18) each with a piston head (16A; 18A) are provided which the air compression chamber. (32) faces and partially limits it, each gas spring having a gas expansion chamber which is partially delimited by the associated piston (16; · 18) (28, "30), the gas expansion chambers (28J 30) can be filled with compressed gas and a tensioning means (48) for movement the piston (16; 18) while increasing the volume of the air compression chamber (32) and further compressing the pressurized gas in each gas expansion chamber (28; 30) and a Compensating duct (31) for connecting each gas expansion chamber (28; 30) to at least one other gas expansion chamber (30; 28) are provided so that the forces as a result of the movement of the gas springs connected to one another essentially are the same. 5. Compressed air gun according to claim 4 ·, characterized through a single point (24) for introducing the pressurized gas into the interconnected Gas expansion chambers (28J 30). 6. compressed air gun according to claim 4 or 5, characterized characterized in that the pistons (16; 18) are mechanically interconnected by coupling means (44; 46) connected and via the same by means of the clamping device (48) can be moved simultaneously. 7. Compressed air gun, especially air rifle, with a Barrel, which is loaded at the rear end with the respective projectile, and with an outer main cylinder with a Air compression chamber, which communicates with the rear end of the barrel via a connecting channel, thereby characterized in that the outer master cylinder (10) has a bore which contains two gas springs, each of which has a stationary hollow inner cylinder (12, 14), which is arranged within a portion of the bore of the outer master cylinder (10), and between the bore and the inner cylinder (12, 14) an annular space is provided, each gas spring also one on one side has open hollow piston (16, 18) which is partially in the annular space for reciprocating movement on the relevant; Inner cylinder (12 ·, 14) is installed, the inner cylinder (12) and the hollow piston (16) of one gas spring being a j first gas expansion chamber (28) and the inner cylinder (14); and the hollow piston (18) of the other gas spring has a second! Form gas expansion chamber (30), the piston heads (16A, 18A) of the two hollow pistons (16, 18) facing each other and partially delimiting the air compression chamber (32), with on the wall of the The bore of the master cylinder (10) is provided with seals (17) resting against it, further seals (26, 27) in each gas spring between the hollow piston (16 or 18) and the respective inner cylinder (12 or 14) are provided for sealing the two gas expansion chambers (28, 30) which receive a compressed gas, a compensation channel (31) the two gas expansion chambers (28, 30) to compensate for the two hollow pistons (16, 18) constantly connects the acting pressures, Clamping means (44, 46, 48) for simultaneous moving apart of the two hollow pistons (16, 18) with a reduction the volumes of the two gas expansion chambers (28, 30) and an increase in the volume of the air compression chamber (32) are provided, and the trigger with a pawl (50) for the simultaneous release of the two cocked Ηοηΐτ pistons (16, 18) cooperate so that they compress the air in the air compression chamber (32) to the projectile (37) to be driven out of the barrel (38).