GB2536313A

GB2536313A - Apparatus for firing a product

Info

Publication number: GB2536313A
Application number: GB1512246.8A
Authority: GB
Inventors: David Page Alan
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-03-12
Filing date: 2015-07-13
Publication date: 2016-09-14
Anticipated expiration: 2035-07-13
Also published as: GB201512246D0; GB201504262D0; GB2536313B

Abstract

An apparatus for firing a product comprises a body portion (1), a discharge chamber (14) in the body portion, an elongate member (5) which is slideable in the body portion, first means which may be a spring and/or magnet (6, 7) for moving the elongate member to a non- firing position, and a second means (36), which is a fluid such as compressed air, for moving the elongate member to a firing position. The apparatus being such that the elongate member moves from the non-firing position to the firing position when pressure from the second means exceeds pressure from the first means; the elongate member moves from the firing position to the non-firing position when pressure from the first means exceeds pressure from the second means. The elongate member comprises a downstream end (37) and an upstream end (38) that is telescopically retained by the downstream end. The downstream end is of either similar or larger diameter than an exhaust port (17) at the upstream end.

Description

APPARATUS FOR FIRING A PRODUCT

This invention relates to apparatus for firing a product.

There are many different types of product firing apparatus. Thus for example, the apparatus may be a firearm, for firing a product in the form of a bullet, a staple gun for firing a product in the form of a staple, or a rivet gun for firing a product in the form of a rivet. The known types of product firing apparatus operate in many different ways and come in many different designs.

It is an aim of the present invention to provide apparatus for firing a product, which apparatus operates in a novel, simple and highly effective manner.

Accordingly, the present invention provides apparatus for firing a product, which apparatus comprises a body portion, a discharge chamber in the body portion, an elongate member which is slideable in the body portion, first means for moving the elongate member to a non-firing position, and a second means for moving the elongate member to a firing position: and the apparatus being such that the elongate member moves from the non-firing position to the firing position when pressure from the second means exceeds pressure from the first means; the elongate member moves from the firing position to the non-firing position when pressure from the first means exceeds pressure from the second means, the second means is a compressible fluid, the elongate member comprises a downstream end and an upstream end, the upstream end is telescopically retained by the downstream end, and the downstream end is of either similar or larger diameter than an exhaust port at the upstream end.

The compressible fluid may be any suitable and appropriate gas. The gas may be a single gas or a mixture of gases. The gas may be air, oxygen, hydrogen, helium, nitrogen, carbon dioxide, nitrous oxide, propane or steam. The gas may comprise oxidising gases containing air, oxygen, ozone or oxides of nitrogen, and fuel gases containing hydrogen, methane, ethane, propane, hydrazine, ammonia, alcohols, amines and organic peroxides, and organic monopropellants.

The compressible fluid may be a supercritical fluid, i.e. a fluid which is at a temperature and pressure above its critical point, where distinct liquid and gas phases no longer exist, and where there is instead a supercritical fluid phase completely filling its area of containment. The supercritical fluid is still compressible, and it is unable to condense to a liquid whilst it is under supercritical fluid conditions of temperature and pressure. The use of a supercritical fluid may be advantageous in the apparatus of the present invention because of the far higher vapour pressures available at elevated temperatures, the impossibility of condensation, and the possibility of employing monopropellant mixtures of critical gases. When a supercritical fluid is employed, then all parts of the apparatus of the present invention coming into contact with the supercritical fluid will normally be maintained at or above the supercritical temperature of the fluid.

The first means may be a spring and a magnet, a spring, or a magnet. Devices other than springs and or magnets may be employed. Where a spring is employed, either alone or as a component of the first means, then the spring is preferably a coil spring. Springs other than coil springs may be employed.

The elongate member is preferably of a circular cross sectional shape. Other cross section shapes may be employed.

The elongate member may have a central portion positioned between the downstream end and the upstream end, the central portion being of a larger diameter than the downstream end and the upstream end.

The apparatus of the invention may include pressure regulating means for regulating the pressure of the second means.

The apparatus of the invention may include a trigger mechanism. The trigger mechanism may comprise a trigger and a sear.

The apparatus of the present invention may be produced in a wide variety of different designs for a wide variety of different uses. Thus, for example the apparatus may be produced such that it is a single firing apparatus, a semi-automatic firing apparatus, or an automatic firing apparatus. The apparatus may be a single use, or alternatively, a non-reloadable apparatus. The apparatus may be produced such that it fires using internal combustion, or not using internal combustion. Alternatively, the apparatus may be such that it fires without using internal combustion.

The apparatus of the present invention may be produced as a firearm, in which case the product fired will usually be a shell, a bullet, or shot. The firearm may be a single shot firearm, a semi-automatic firearm, an automatic firearm or a single use, non re-loadable firearm. The firearm may be a low powered firearm, a medium powered firearm, or a high powered firearm, a low/medium/high powered air gun or gas gun.

In alternative embodiments of the invention, the apparatus of the present invention may be a tool. For example, the apparatus of the invention may be a nail gun for firing a product in the form of a nail.

The apparatus of the invention may be embodied in projectiles such as rockets, bombs, darts or bullets.

The apparatus of the present invention may alternatively be a harpoon gun for firing a harpoon, or a spear gun for firing a fish spear.

Still further, the apparatus of the present invention may be medical or cosmetic apparatus for firing at least one product through the skin into the blood stream or tissues of humans or animals. In this case, the product may be a pharmaceutical product or a medicine. The product may be in be in any suitable and appropriate form, for example in the form of a powder or a liquid. If desired, the product may be in the form of biological material such as hair follicles, cells, cellular, sub-cellular or genetic materials, bacteria, viruses, fungi, chemical substances, electronic devices, or nano-mechanisms.

In the above examples of apparatus of uses of the present invention, it will be apparent that the product that is fired actually leaves the apparatus and does not return. This is not always necessary and, for example, the apparatus of the present invention may be constructed for firing a product that does not actually leave the apparatus but that moves to and fro in a reciprocal manner. Thus, for example the apparatus may be a hammer apparatus for causing the repeated operation of a product in the form of a hammer, or chisel apparatus for causing the repeated operation of a product in the form of a chisel. Still further, the apparatus of the present invention may fire a needle, or matrix of needles into the skin of a human or animal for the purpose of subsequently passing a material such for example as a pharmaceutical product, a serum or a pigment through or around the needle or needles and into the skin, blood stream or other appropriate tissues of the humans or animals.

The apparatus of the present invention may be embodied within a projectile, such as a dart or harpoon. In this case, it may be that trigger part or its functional equivalent is released upon impact or contact with a target.

The apparatus of the present invention may be made from any suitable and appropriate materials. The materials will vary depending on the intended use of the apparatus of the invention. Thus, for example, the apparatus may be made of metals, plastics materials, ceramic materials, and combinations of these materials.

The apparatus of the present invention may be constructed to operate with seals, or without seals, and relying on close fitting parts or flexible metallic or composite bellows to achieve gas sealing.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 is a cross sectional view through first apparatus of the present invention; Figure 2 is a cross sectional view through second apparatus of the present invention; Figure 3 is a cross sectional view through third apparatus of the present invention; Figure 4 is a cross sectional view through fourth apparatus of the present invention; and Figure 5 is a cross sectional view through fifth apparatus of the present invention.

Referring to the drawings, Figure 1 illustrates apparatus which is configured as an air or gas operated weapon or tool firing mechanism, which uses a propellant medium pressurised air, or a gas or gases.

The apparatus comprises a body portion in the form of a body shell 1. The apparatus 2 also comprises a valve head 2. The valve head 2 abuts a valve seat 3. A compression spring 4 biases the valve head 2 against the valve seat 3 in order to form an hermetic seal. Both the valve head 2 and the spring 4 are housed within, and retained by, an elongate member 5. A front part of the elongate member 5 includes a housing for the spring 4. The front part of the elongate members 5 is preferably of circular cross section. The remaining length of elongate member 5 may, if so desired, be other than of circular in section.

The elongate member 5 is free to slide in the body shell 1. The elongate member 5 is retained in a pre-firing, or cocked position, as depicted in Figure 1, by a bias which is compounded of the sum of the attractive force of a magnet 6, and the compressive force applied by a compression spring 7.

The magnet 6 and the compression spring 7 thus form first means for moving the elongate member 5 to a non-firing position. The magnet 6 is fixed in position in the body part 1. The magnet 6 acts on an attractor 16. The attractor 16 may be integral with the elongate member, or non-integral as shown.

The elongate member 5 is further retained in the pre-firing position, as shown, shown by a ball or roller sear 8 and a trigger blade 9. The trigger blade 9 depends from a trigger pivot 10. The trigger pivot 10 is housed in a part 11 in the form of a projection from the body shell 1. The trigger 9 is retained in the pre-firing position by a bias applied by an extension spring 12. The extension spring 12 depends from a part 13 a projection from the body shell 1.

A second means 36 is for moving the elongate member to a firing position.

A valve chamber 14 is fed by a high pressure. The pressure is preferably a pressure regulated supply of gas or air from a reservoir (not shown).

The elongate member 5 moves from the non-firing position to the firing position when pressure from the second means 36 exceeds pressure from the first means 6, 7. The elongate member 5 moves from the firing position to the non-firing position when pressure from the first means 6, 7 exceeds pressure from the second means 36. The second means 36 is a fluid.

The elongate member 5 comprises a downstream end 37 and an upstream end 38. The upstream end 38 is telescopically retained by the downstream end 37. The downstream end 37 is able to be of either a similar or larger diameter than an exhaust part 17 at the upstream end 38.

An operating cycle of the apparatus is as follows. The chamber 14 is pressurised to a predetermined pressure by a restricted feed via the port 15. The predetermined pressure exceeds the pressure required to overcome the compound spring 7 and magnetic biases applied to the elongate member 5. This results in the elongate member 5 being biased to move rearward, and constrained from so doing by the ball or roller sear 8. Upon application of sufficient pressure to the trigger blade 9, the elongate member 5 pivots about the pivot part 10 until the sear ball or roller 8 is no longer supported by the trigger blade 9, and is disengaged from a recess in the elongate member 5. This thus permits the elongate member 5 to accelerate rearward until it abuts the rear, downstream end of the body shell 1.

Towards the end of the travel of the elongate member 5, an internal flange in the upstream end of the elongate member 5 comes into abutment with the valve head 2. The valve head 2 is then snatched rearward until the front face of the valve head 2 clears the valve seat 3 by a distance equal to 0.25 (and preferably 0.5) times the diameter of an exhaust port 17. This causes the valve head 2 to be withdrawn into the chamber 14 far enough for the front face of the valve head 2 to be clear of the low pressure region formed in front of the now fully exposed port 17. The valve head 2 is thus fully exposed to the rapidly reducing pressure within the chamber 14, as part of the contents of the chamber 14 are exhausted into a gun barrel or pneumatic tool. When the contents of the chamber 14 are exhausted to a predetermined residual chamber pressure, the pneumatic bias applied to the upstream end of the elongate member 5 is overcome by the rising rate bias applied by the magnet 6 and the compression spring 7. This causes the elongate member 5 to accelerate in a forward upstream direction, until the attractor 16 abuts the magnet 6, and the valve head 2 is re-seated against the valve seat 3, thus terminating the firing cycle.

The ancillary ball or roller sear 22, the plunger 25 and an optional compression spring 24 provide an interface for the indexing of a magazine or other ancillary weapon or tool system. Figure 1 shows a breach end 18 of an air gun barrel, an air gun pellet 19 in situ, and an '0' ring breach seal 20. These components are included to illustrate the advantageous unrestricted and short path, between the air or gas charge and a projectile, that is made possible with the illustrated apparatus of the present invention.

Figure 2 illustrates apparatus of the present invention which is configured as an air or gas operated weapon or tool firing mechanism incorporating integral means for chamber pressure regulation, and thus eliminating the requirement for a pressure regulated air or gas supply from the reservoir. Similar parts as in Figure 1 have been given the same reference numbers for ease of comparison and understanding.

An operating cycle of the apparatus shown in Figure 2 is as follows. The chamber 14 is pressurised by air or gas from a high pressure reservoir via a port 15 by means of a conduit including an on / off manually re-settable flow control valve (not illustrated) actuated by either of plungers 25 or 27.

The elongate member 5 is biased in the forward or upstream direction by a bias compounded of the attractive force exerted by the magnet 6 on the attractor 16, a compressive load applied by the compression spring 7, and the bias applied to the elongate member 5 by the compression spring 7 via the plunger 27 and the ball or roller sear 8. When the pneumatic bias, applied to the front or upstream end of the elongate member 5 by pressure in the chamber 14, exceeds the opposing compound bias, the elongate member 5 springs in a rearward or downstream direction until it abuts the trigger primary sear 29, which is retained in the pre-firing or cocked condition by a secondary sear 30. Both the primary sear 29 and the secondary sear 30 are biased in an anticlockwise direction as indicated by arrows on Figure 2. The small rearward movement of the elongate member 5 causes the plunger 25 to retract, and the plunger 27 to extend by a small increment. One or other of these actions may be employed to trip the on/off valve to the off position, thus regulating the maximum chamber pressure. The plunger 25 or 27 not employed in the pressure regulation may be utilised for a further weapon or tool function, such for example as a shot or cycle tally counter.

Upon temporary disengagement of the secondary sear 30 by a tertiary trigger part (not shown), the elongate member 5 accelerates rearward under pneumatic bias until the elongate member 5 abuts the body shell 1 at point B. This drives magazine indexer probe 26 rearward, snatching the valve head 2 from the valve seat 3 as it does so. The magazine (not shown) is indexed to present a subsequent round upon the return stroke of the elongate member 5 and indexer probe 26. The flow control valve (not shown) remains in the off condition until it is manually re-set prior to a subsequent shot or tool cycle.

Figure 3 illustrates apparatus of the present invention which is configured as a fully automatic air or gas operated weapon or tool firing apparatus. Similar parts as in previous Figures have been given the same reference numbers.

An operating cycle of the apparatus shown in Figure 3 is as follows. Compressed air, gas or gases are fed to a trigger actuated inlet valve 31, not illustrated but represented by a stopcock 31. The feed is via the conduit 15 connected to a high pressure air or gas source and preferably via a barostat in order to achieve consistent performance. Upon application of pressure to the trigger blade 9, the inlet valve 31 opens, admitting air or gas to the chamber 14. The pressure in the chamber 14 rises rapidly, applying increasing pressure to the front of the elongate member 5. The elongate member 5 is biased in the forward, or downstream direction by a compound bias comprised of the attractive force between the magnet 6 and the attractor 16, the compressive force applied by the compression return spring 7 and the bias applied to the elongate member 5 by the compression spring 27 via the ball or roller detent sear 8. When the pressure in the chamber 14 exerts sufficient pressure on the front of the elongate member 5, the opposing bias is overcome. The ball or roller sear 8 is displaced downward as the elongate member 5 is accelerated rearward, or downstream until the elongate member 5 abuts the end wall of body shell 1. In transit, the elongate member 5 snatches the valve head 2 from the valve seat 3, thus partially discharging the contents of the chamber 14 into a weapon barrel breach, or an air tool. As gas is discharged from the chamber 14, a point is reached where the residual bias acting on the front of the elongate member 5 is overcome by the opposing rising rate bias applied by magnet 6 and the compression spring 7. This causes the elongate member 5 to be accelerated in the forward or upstream direction, re-seating valve head 2 and thus terminating the cycle.

The cycling rate is determined by the rate of air or gas feed. The ball or roller sear 22, the plunger 25 and the compression spring 24 provide an optional mechanical interface for actuation of other ancillary weapon or tool parts, such for example as a magazine indexing mechanism, as also does the elongate projection 26.

Figure 4 illustrates apparatus of the present invention which configured as a fully automatic weapon or tool firing apparatus employing the internal combustion of monopropellants or fuels and oxidising agents, comprised of compressed gas, gases or gas and liquid or gases and liquids. Similar parts as in previous Figures have been given the same reference numbers.

An example of an operating cycle of the apparatus as shown in Figure 4 is as follows. Upon application of the trigger blade 9, one of a pair of non-return flow control valves 31 opens, admitting a pressure regulated charge of a flammable gas, for example methane, to the chamber 14 via one of two conduits 15. The second flow controller (not shown) opens in response to a predetermined pressure in chamber 14, admitting, for example compressed air or other oxidising gas, to enter the chamber 14. This causes the elongate member 5 to be biased in the rearward downstream direction until the elongate member 5 overcomes the opposing bias, compounded of the attractive force between the magnet 6 and the attractor 16 and the bias applied to the elongate member 5 by the compression spring 27 via the ball or roller sear 8, as in the apparatus shown in Figure 3. At this point, the elongate members is accelerated rearward, and the plunger 25 and the ball or roller sear 22 descend into the recess in the elongate member 5 under bias from the compression spring 24. This action is employed to trigger an electrical ignition circuit (not shown) timed to initiate a spark at ignition means 32 as or when, the valve head 2 has been pulled clear of the valve seat 3. The bias applied by the compression spring 24 to the ball or roller sear 22 via the plunger 25 is sufficient to detain the elongate member 5 in its rearward position until the pressure in the chamber 14 falls to atmospheric pressure, or less, and before the pressure is overcome by the attraction between the magnet 6 and attractor 16. The elongate member 5 then accelerates in the forward or upstream direction, re-seating the valve and terminating the cycle. The elongate projection 26 at rear end of member 5 is intended as a mechanical interface with a magazine indexing mechanism, not shown.

Figure 5 illustrates a further fully automatic internal combustion apparatus. Similar parts as in previous Figures have been given the same reference numbers.

An example of an operating cycle of the apparatus shown in Figure 5 is as follows. The chamber 15 is continuously supplied with pressurised fuel gas to a predetermined pressure via a barostat and non-return valve, and via one of two ports 15. The second port 15 is continuously connected to a pressure responsive flow control valve, feeding the chamber 14 with a pressure regulated supply of air or other oxidising gas or gases to a constant, predetermined maximum pressure. This pressure is sufficient to pneumatically bias the elongate member 5 such that it springs in a rearward or downstream direction, overcoming the opposing compound bias comprised of the magnetic attraction between the magnet 6 and the attractor 16, and the bias applied to the elongate member 5 by the compression spring 32 via the plunger 33 and the ball or roller sear 34, until the elongate member 5 is arrested by the primary trigger sear 29. The primary trigger sear 29 is retained in the pre-firing or cocked position by the secondary trigger sear 30 until temporarily disengaged by a tertiary trigger part, not shown. Upon sear disengagement, the elongate member 5 accelerates in a rearward or downstream direction until it abuts the body shell 1 at point B. The elongate member 5 pulls the valve head 2 clear of valve seat 3 during the transit of the elongate member 5 from point A to point B. Also the plunger 25 is retracted, and the plunger 33 is extended. Either one or other of these actions is employed to trigger an electrical ignition circuit not shown, initiating a spark at the ignition source 35 when the valve is in the partially or fully open position. The plunger action not employed may, if desired, be used to trigger some other tool or weapon ancillary mechanism.

The bias applied to the elongate member 5 by the compression spring 24 via the plunger 25 and the ball or roller sear 22 is sufficient to delay the return stroke of the elongate member 5 until the pressure within the chamber 14 falls to or below atmospheric pressure when subject to barrel extraction, in order to best facilitate induction of a subsequent gas charge. Upon release of the tertiary trigger means, the primary and secondary sears 29 and 30 reengage under the torsion spring biases indicated by arrows on Figure 5. This interrupts the last of a series of cycles. The part 26 is a projection of an ancillary magazine indexing mechanism.

It is to be appreciated that the embodiments of the invention described above with reference to the accompanying drawings have been given by way of example only. Individual components shown in the drawings are not limited to use in their drawings and they may be used in other drawings and in all aspects of the invention.

Claims

CLAIMS1. Apparatus for firing a product, which apparatus comprises a body portion, a discharge chamber in the body portion, an elongate member which is slideable in the body portion, first means for moving the elongate member to a non-firing position, and a second means for moving the elongate member to a firing position: and the apparatus being such that the elongate member moves from the non-firing position to the firing position when pressure from the second means exceeds pressure from the first means; the elongate member moves from the firing position to the non-firing position when pressure from the first means exceeds pressure from the second means, the second means is a fluid, the elongate member comprises a downstream end and an upstream end, the upstream end is telescopically retained by the downstream end, and the downstream end is of either similar or larger diameter than an exhaust port at the upstream end.
2. Apparatus according to claim 1 in which the fluid is a gas or a supercritical fluid.
3. Apparatus according to claim 2 in which the gas is air, oxygen, hydrogen, helium, nitrogen, carbon dioxide, nitrous oxide, propane or steam.
4. Apparatus according to claim 2 in which the supercritical fluid is carbon dioxide or nitrous oxide.
5. Apparatus according to any one of the preceding claims which the gas comprises oxidising gases containing air, oxygen, ozone or oxides of nitrogen, and fuel gases containing hydrogen, methane, ethane, propane, hydrazine, ammonia, alcohols, amines and organic peroxides, and organic monopropellants.
6. Apparatus according to any one of the preceding claims in which the first means is a spring and a magnet.
7. Apparatus according to any one of claims 1 -5 in which the first means is a spring.
8. Apparatus according to any one of claims 1 -5 in which the first means is a magnet
9. Apparatus according to any one of the preceding claims in which the elongate member is of a circular cross sectional shape.
10. Apparatus according to any one of the preceding claims in which the elongate member has a central portion positioned between the downstream end and the upstream end, the central portion being of a larger diameter than the downstream end and the upstream end.
11. Apparatus according to any one of the preceding claims and including pressure regulating means for regulating the pressure of the second means.
12. Apparatus according to any one of the preceding claims and including a trigger mechanism.
13. Apparatus according to claim 12 in which the trigger mechanism comprises a trigger and a sear.
14. Apparatus according to any one of the preceding claims and which is a single firing apparatus, a semi-automatic firing apparatus, or an automatic firing apparatus.
15. Apparatus for firing a product, substantially as herein described with reference to the accompanying drawings.