Air gun firing system

Information

  • Patent Grant
  • 6360736
  • Patent Number
    6,360,736
  • Date Filed
    Friday, February 18, 2000
    25 years ago
  • Date Issued
    Tuesday, March 26, 2002
    22 years ago
  • Inventors
  • Original Assignees
  • Examiners
    • Poon; Peter M.
    • Copier; Florie C.
    Agents
    • Pro-Techtor International Services
Abstract
An air gun firing system, working in conjunction with an air gun with a barrel and comprising: a bullet chamber on the front end of the main body, connected with the barrel for housing a bullet to be fired through the barrel; a lock, glidingly movable along the axis of the barrel, pushing the bullet into the bullet chamber, as driven by a lock driver, enabling the bullet to be fired, with a spring pulling back the lock; a gas chamber for driving the lock driver, accommodating the lock driver; a high-pressure gas container; a first pressure reducing valve; a second pressure reducing valve; and an electromagnetic valve, controlling flow of low-pressure gas into the gas chamber. When the electromagnetic valve opens, low-pressure gas flows into the gas chamber, driving the lock driver. When the electromagnetic valve closes, the spring pulls back the lock and the lock driver.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an air gun firing system for use in an air gun.




2. Description of Related Art




Rifle shooting contests using air guns are a common recreational pastime. Air guns are divided into single-loaders and semiautomatic or fully automatic repeating guns.




A conventional air gun has a barrel with a bullet chamber, accommodating a bullet to be fired. A guiding tube is set on the barrel, guiding bullets that fall into the bullet chamber to be fired. However, the bullets have low weights and consequently fall into the bullet chamber only at a relatively low feeding rate. During continuous operation only a limited firing rate of bullets is possible, which is below 180 bullets per minute. A higher firing rate leads to attempted firing although the bullet to be fired has not yet entered the bullet chamber, so that automatic firing will be interrupted. Continuous firing of automatic repeating rifles is thus limited to the feeding rate of bullets into the bullet chamber, which is about 180 bullets per minute.




Conventional semi-automatic repeating air guns in principle work like gunpowder-driven rifles. A lock is driven back by gas pressure upon firing a bullet, which is a simple structure. However, since gas pressure directly drives the firing, firing is too fast with no way of being slowed. Therefore only one bullet can be fired at a time. Although semi-automatic repeating rifles have simple structures, restriction to firing of single bullets do not fulfill demands of users.




A conventional fully automatic repeating gun of another type has a bi-directional gas pressure vessel for driving bullets to be fired. Entering of gas into the gas pressure vessel is controlled by an electromagnetic control valve to achieve fully automatic repeated firing. Combining the control valve with the bi-directional gas pressure vessel allows to control the firing rate of the bullets and to stay within the limit set by the feeding rate of bullets.




However, since a bi-directional gas pressure vessel for driving bullets is used, this type of fully automatic repeating gun has a complicated structure, with the bullets occupying a large volume. Furthermore, after a bullet has entered the bullet chamber, the control valve is pushed by a firing device and opens, letting gas with high pressure into the bullet chamber to fire the bullet. Conventional control valves are not cast in a mold and do not allow to be tested for leaks before being used in air guns. Leaks detected only after having completed the air gun require the air gun to be disassembled and assembled again, which makes producing air guns difficult.




SUMMARY OF THE INVENTION




It is the main object of the present invention to provide an air gun firing system with a simple structure and fully automatic repeating operation.




Another object of the present invention is to provide an air gun firing system which does not require a bi-directional gas pressure vessel for simpler control.




A further object of the present invention is to provide an air gun firing system which has a control valve cast in a mold for better reliability.




The present invention can be more fully understood by reference to the following description and accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a sectional side view of the air gun firing system of the present invention in conjunction with an air gun.





FIG. 2

is a schematic illustration of the air gun firing system of the present invention in conjunction with an air gun.





FIG. 3

is a schematic illustration of the movement of the present invention before firing a bullet.





FIG. 4

is a schematic illustration of the movement of the present invention during firing of a bullet.





FIG. 5

is a top view of the control valve of the present invention, showing the inlet and the outlet thereof.





FIG. 6

is a cross-sectional view of the front section of the air gun used in conjunction with the present invention, showing the path of gas.





FIG. 7

is a cross-sectional view of the middle section of the air gun used in conjunction with the present invention, showing the path of gas of low pressure from the second pressure reducing valve to the first conduit.





FIG. 8

is a cross-sectional view of the middle section of the air gun used in conjunction with the present invention, showing the path of gas of medium pressure from the second pressure reducing valve to the medium pressure chamber.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




As shown in

FIG. 1

, the air gun firing system of the present invention is used in conjunction with an air gun, having a main body


10


with an upper side, a lower side, a front end and a rear end, defining a longitudinal direction, with a bullet chamber


11


located at the front end of the main body


10


; a barrel


20


, having a rear end that is attached to the front end of the main body


10


; and a feeding mechanism


40


on the upper side of the main body


10


, feeding further bullets into the bullet chamber


11


to be fired from there.




The air gun firing system of the present invention mainly comprises: a firing device


30


inside the main body


10


, controlling firing of a bullet


50


from the bullet chamber


11


; a high-pressure gas container


60


, supplying gas for driving the bullets


50


to be fired; a trigger device


70


; a control valve


80


; a first pressure reducing valve


90


A; and a second pressure reducing valve


90


B. The trigger device


70


has an electromagnetic valve


71


, an electric control circuit


72


, and a trigger


73


. The control valve


80


, upon being pushed by the firing device


30


, opens, allowing compressed gas to flow into the bullet chamber


11


, pushing out the bullet


50


. The first pressure reducing valve


90


A passes on pressure from the high-pressure gas container


60


reduced to medium pressure for driving the bullet


50


. The second pressure reducing valve


90


B reduces further gas pressure to low pressure, a level borne by the electromagnetic valve


71


and required by the firing device


30


.




Referring again to

FIG. 1

, the bullet chamber


11


in the main body


10


is connected with the barrel


20


at the rear end thereof. A feeding tube


41


, having a lower end, leads to the bullet chamber


11


to feed bullets into the bullet chamber


11


. The feeding tube


41


close to the lower end thereof has several vents


42


, allowing gas that has entered the feeding tube


41


to escape to prevent bullets to enter the bullet chamber


11


without being driven back by gas.




An accommodation chamber


12


is located inside the main body


10


to the rear of the bullet chamber


11


, accommodating the firing device


30


. A medium-pressure chamber


13


is located inside the main body


10


below the bullet chamber


11


. Gas coming from the first pressure reducing valve


90


A enters the medium-pressure chamber


13


. The control valve


80


in a connecting opening


14


connects the medium-pressure chamber


13


and the bullet chamber


11


, controlling entering of gas with medium pressure into the bullet chamber


11


for firing the bullet


50


through the barrel


20


.




As further shown in

FIG. 1

, the high-pressure gas container has an outlet which is connected with the first pressure reducing valve


90


A, from where gas with medium pressure is led into the medium-pressure chamber


13


. A gas tube


15


is attached to the main body


10


from below at the front end thereof, having a free end. A conduit


16


connects the first pressure reducing valve


90


A with the gas tube


15


at the free end thereof. A gas-conducting block


17


leads gas from the gas tube


15


into the medium-pressure chamber


13


, establishing a connection with a gas flow circuit inside the main body


10


(further explained below). Thus gas with medium pressure is led from the first pressure reducing valve


90


A into the medium-pressure chamber


13


.




Referring to

FIGS. 1-5

, the gas-conducting block


17


leads gas with medium pressure into the medium-pressure chamber


13


and, besides this, to the second pressure reducing valve


90


B. Gas entering the second pressure reducing valve


90


B undergoes another reduction of pressure to low pressure and subsequently is led through several conducting openings to the electromagnetic valve


71


. Gas having passed through the electromagnetic valve


71


drives the firing device


30


.




Pressure inside the high-pressure gas container


60


usually is about 1200 psi and is reduced by the first pressure reducing valve


90


A to about 800 psi, which are needed to fire the bullet


50


. Since the electromagnetic valve


71


cannot stand too high a pressure (of more than 180 psi), a passage inside the main body


10


(further explained below) reduces pressure accordingly to reach the electromagnetic valve


71


.




The firing device


30


comprises: a lock


31


with a front end, a rear end and a lower side, glidingly movable inside the accommodation chamber


12


in the longitudinal direction between a rear position and a forward position, pushing the bullet


11


into the bullet chamber


11


and sealing the bullet chamber


11


; a lock driver


32


, attached to the lock


31


on the lower side thereof and cylindrically shaped with an axis along the longitudinal directions; and a spring


33


. The lock driver


32


is driven by low-pressure gas passing through the electromagnetic valve


71


and drives the lock


31


in a forward movement. The spring


33


pulls back the lock


31


and the lock driver


32


to the rear positions thereof after the bullet


50


has been fired.




Referring to

FIGS. 1-3

, the main body


10


has a gas chamber


18


with an inner wall, located below the accommodating chamber


12


and accommodating the lock driver


32


. At least one sealing ring


321


is laid around the lock driver


32


, gliding along the inner wall of the gas chamber when the lock driver


32


moves. As shown in

FIG. 2

, gas from the high-pressure gas container


60


, after passing through the first and second pressure reducing valves


90


A,


90


B, reaches the electromagnetic valve


71


through a conduit


91


.




Referring again to

FIG. 5

, the electromagnetic valve


71


has at least one inlet


711


, an outlet


712


, and a vent


713


. The inlet


711


is connected with the conduit


91


, allowing low-pressure gas to reach the electromagnetic valve


71


. When the electromagnetic valve


71


is open, the at least one inlet


711


, the outlet


712


and the vent


713


are all connected, so that gas, after entering through the inlet


711


flows out through the outlet


712


.




As shown in

FIG. 2

, the outlet


712


of the electromagnetic valve


71


is connected with the gas chamber


18


. Therefore, when the electromagnetic valve


71


is open, low-pressure gas coming from the second pressure reducing valve


90


B enters the gas chamber


18


, driving the lock driver


32


(as shown in FIG.


4


).




Referring to

FIGS. 1 and 2

, the electromagnetic valve


71


is controlled by the electric control circuit


72


to open or close. The electric control circuit


72


has a switch


74


which is operated by the trigger


73


. When the trigger


73


is manually pulled, the electromagnetic valve


71


is opened or closed, so that firing the bullet


50


is manually controlled.




The electric control circuit


72


generates an acoustic signal which is sent out at a controlled rate after pulling the trigger


73


, with the electromagnetic valve


71


opening and closing at the controlled rate. Thus, on pulling the trigger


30


, the firing device


30


starts to operate repeatedly, and fully automatic repeating operation of the air gun is achieved.




The lock


31


of the firing device


30


serves to push the bullet


50


into the bullet chamber


11


and to seal the bullet chamber


11


at the rear end thereof, so that, when medium-pressure gas enters the bullet chamber


11


, the bullet


50


will be pushed through the barrel


20


. The spring


33


is fastened to the rear end of the lock


31


and thus expanded when the lock


31


moves forward (as shown in FIG.


4


), developing an elastic force that pulls the lock


31


back as soon as no gas in the gas chamber


18


has a driving force anymore.




Furthermore, as shown in

FIG. 3

, the lock


31


on the front end thereof has an opening


311


with an inner peripheral wall in which a lock head


312


is inserted. The lock head


312


has a periphery close to the inner peripheral wall of the opening


311


, leaving several gas paths


313


in between. A bottom hole


314


on the lower side of the lock


31


allows gas to enter the opening


311


.




As shown in

FIG. 4

, when the lock


31


moves forward, pushing the bullet


50


into the bullet chamber, the front end thereof seals the bullet chamber


11


at the rear end thereof. At this time, the bottom hole


314


of the lock


31


is aligned with the connecting opening


14


between the medium-pressure chamber


13


and the bullet chamber


11


. Then, gas in the medium-pressure chamber


13


is enabled to enter the opening


311


of the lock through the connecting opening


14


and the bottom hole


314


and subsequently passes through the gas paths


313


around the lock head


312


, entering the bullet chamber


11


to drive out the bullet


50


through the barrel


20


.




Furthermore, as shown in

FIG. 3

, while the lock


31


has not yet sealed the bullet chamber


11


, the control valve


80


is closed. When the lock


31


has moved forward, sealing the bullet chamber


11


, the control valve is pushed open by the lock driver


32


, allowing gas from the medium-pressure chamber


13


to flow to the connecting opening


14


and from there to the bullet chamber


11


.




As shown in

FIGS. 3 and 4

, the control valve


80


comprises: a valve body


81


with a top side and a front side, into which an opening


85


is cut; a pushing rod


82


, glidingly movable in the valve body


81


along the longitudinal direction, passing through the opening


85


; a spring


83


on the pushing rod


82


, leaning against the valve body


81


; and a plug


84


on the front end of the pushing rod


84


. The pushing rod


82


has a rear end that points to the lock driver


32


. A top hole


86


, cut into the top side of the valve body


81


connects the opening


85


with the connecting opening


14


, establishing a connection between the medium-pressure gas chamber


13


and the connecting hole


14


.




The pushing rod


82


has a holding ring


87


on the rear end thereof. The spring


83


is inserted between the holding ring


87


on the pushing rod


82


and the valve body. Thus the spring


83


is held on the pushing rod


82


, so that the valve body


81


, the pushing rod


82


and the spring


83


form a unit which will not disintegrate and are easy to mount.




As shown in

FIG. 3

, when the pushing rod


82


is in a rearmost position, the plug


84


covers and seals the opening


85


, closing the control valve


80


, such that no gas from the medium-pressure chamber


13


will enter the bullet chamber


11


. When pushed by the lock driver


32


, as shown in

FIG. 4

, the pushing rod


82


moves forward, lifting the plug


84


from the opening


85


and allowing gas to pass through the opening


85


and the top hole


86


to reach the connecting opening


14


and from there the bullet chamber


11


to drive out the bullet


50


.




As compared to a conventional firing device, the firing device


30


of the present invention is mainly characterized by a movement that is caused by gas pressure driving the lock driver


32


from the rear position thereof. In the forward position of the lock


31


and the lock driver


32


, the electromagnetic valve


71


cuts flowing of gas into the gas chamber


18


, which causes the lock


31


and the lock driver


32


to be drawn back to the rear position thereof by the spring


33


. Thus the present invention does not need to employ a bi-directional gas container and still achieves fully automatic repeating operation with a simple structure and low cost.




Since the firing device


30


has only unidirectional driving by gas for repeating operation, gas pressure from a single direction is sufficient, and no bi-directional gas pressure with a corresponding distribution system is needed, greatly simplifying the structure of the firing device


30


.




Conventional pressure reducing devices usually employ mechanical valves, therefore refilling gas used up for firing bullets is often not sufficient, leading to a decreasing pressure at repeating operation and consequently to insufficient firing rates and impaired stability of repeating operation.




In order to solve this problem, the present invention has storage spaces inserted between the first and second pressure reducing valves


90


A,


90


B and the bullet chamber


11


and the gas chamber


18


, respectively. Thus, pressure stored in the storage spaces compensates insufficient refilling by the first and second pressure reducing valves


90


A,


90


B due to a high firing rate.




The present invention has a gas distribution system as follows: As shown in

FIGS. 1 and 2

, gas flows from the first pressure reducing valve


90


A into the gas tube


15


. The gas tube


15


is a hollow tubular body with a connected end that is connected to the gas-conducting block


17


. From the free end of the gas tube


15


, a plug


151


is inserted therein, connected with the gas-conducting block


17


by a screw


152


, so that the gas tube is fastened to the gas-conducting block


17


from below. The gas tube


15


has an inner space that forms a storage space


153


, taking in gas from the first pressure reducing valve


90


A.




Referring to

FIGS. 1 and 6

, the gas-conducting block


17


has a rear side, a lower side and an upper side with an opening that is aligned with the medium-pressure chamber


13


and accommodates the second pressure reducing valve


90


B. Below the medium-pressure chamber


13


and the second pressure reducing valve


90


B two conduits pass through the main body


10


in the longitudinal direction. The conduit


91


conducts low-pressure gas from the second pressure reducing valve


90


B, and the conduit


92


conducts medium-pressure gas.




As shown in

FIG. 6

, two exit ducts


171


,


172


lead away from the upper side of the gas-conducting block


17


. The exit duct


171


connects the lower side of the gas-conducting block


17


and the second pressure reducing valve


90


B, allowing gas from the storage space


153


to enter the second pressure reducing valve


90


B. The exit duct


172


connects the lower side of the gas-conducting block


17


and the conduit


92


, allowing gas from the storage space


153


to enter the conduit


92


.




As shown in

FIGS. 1 and 7

, a low-pressure gas outlet


93


on the rear side of the gas-conducting block


17


connects the second pressure reducing valve


90


B and the conduit


91


. The conduit


91


leads from the front end to the rear end of the main body


10


. The electromagnetic valve


71


is located below the gas chamber


18


. A duct


95


close to the rear end of the main body


10


connects the conduit


91


with the inlet


711


of the electromagnetic valve


71


, and a duct


96


connects the outlet


712


of the electromagnetic valve


71


with the gas chamber


18


. Thus gas from the second pressure reducing valve


90


B is able to enter the gas chamber


18


and to drive forward the lock driver


32


.




Furthermore, as shown in

FIG. 8

, medium-pressure gas from the storage space


153


enters the conduit


92


through the duct


172


, with the conduit


92


located below the medium-pressure chamber


13


. A duct


94


connects the conduit


92


and the medium-pressure chamber


13


, allowing medium-pressure gas to enter the medium-pressure chamber


13


. As shown in

FIG. 3

, the control valve


80


is located on the rear end of the medium-pressure chamber


13


, controlling flow of gas to the connecting opening


14


to reach the bullet chamber


11


.




With the storage space


153


, the conduits


91


,


92


and the medium-pressure chamber


13


having gas-storing capabilities, pressure decreases during repeating operation of the air gun are attenuated, allowing to maintain a high firing rate.




While the invention has been described with reference to a preferred embodiment thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention which is defined by the appended claims.



Claims
  • 1. An air gun firing system comprising:a main body, a barrel with a front end and a rear end, a bullet chamber on said front end of said main body, said bullet chamber is connected with said rear end of said barrel for housing a bullet to be fired through said barrel, a lock having a rear end and glidingly movable along a longitudinal axis of said barrel, said lock pushing said bullet into said bullet chamber when said lock is moved forward from a rear position, said lock sealing said bullet chamber when said lock is moved forward, thereby enabling said bullet to be fired, a lock driver attached to said lock, a spring attached to said lock and to said main body, said spring returning said lock and said lock driver to an initial position after said bullet has been fired, a gas chamber housing said lock driver such that said lock driver is movable within said gas chamber parallel to said longitudinal axis of said barrel, and a gas supply system, said gas supply system supplying gas to drive said lock driver and to fire said bullet.
  • 2. The air gun firing system according to claim 1, wherein:said air gun firing system further comprises a high pressure gas container, a first pressure reducing valve to convert gas supplied by said high-pressure gas container to medium-pressure gas, a medium-pressure chamber that is supplied by said first pressure reducing valve and supplying said bullet chamber with said medium-pressure gas, a second pressure reducing valve to converting said medium-pressure gas supplied by said first pressure reducing valve to low-pressure gas, and a control valve between said first pressure reducing valve and said bullet chamber to control flow of said medium-pressure gas into said bullet chamber; wherein said control valve comprises a valve body having a front side facing said medium-pressure chamber, said front side of said valve body comprises an opening, a pushing rod glidingly movable in said valve body in a direction of said longitudinal axis, said pushing rod passing through said opening, said pushing rod having a rear end with a holding ring set on said rear end of said pushing rod, a plug on said front end of said pushing rod tightly covering said opening when said pushing rod is in a retracted position, and a spring on said pushing rod positioned between said valve body and said holding ring, said spring urging said pushing rod towards said retracted position; and wherein wherein said control valve is opened by said lock driver when said lock is moved forward.
  • 3. An air gun firing system comprising:a main body a barrel with a front end and a rear end, a bullet chamber on said front end of said main body, said bullet chamber is connected with said rear end of said barrel for housing a bullet to be fired through said barrel, a firing device movable parallel to a longitudinal axis of said barrel, said firing device pushes said bullet into said bullet chamber, thereby enabling said bullet to be fired, and a spring deployed between said firing device and said main body, said spring returning said firing device to an initial position after said bullet has been fired.
  • 4. The air gun firing system according to claim 3, wherein:said air gun firing system further comprises a gas chamber to drive said firing system, a high-pressure gas container, a first pressure reducing valve to convert gas supplied by said high-pressure gas container to medium-pressure gas, a medium-pressure chamber that receives said medium-pressure gas from said first pressure reducing valve and supplies said bullet chamber with said medium-pressure gas, a second pressure reducing valve, converting said medium-pressure gas supplied by said first pressure reducing valve to low-pressure gas, a control valve between said first pressure reducing valve and said bullet chamber to control a flow of said medium-pressure gas into said bullet chamber, said control valve being opened by said firing system so as to allow said medium-pressure gas to flow into said bullet chamber, and an electromagnetic valve to control a flow of said low-pressure gas into said gas chamber, with a storage space receiving said medium-pressure gas from said first pressure reducing valve and supplying said second pressure reducing valve and said medium-pressure chamber.
  • 5. The air gun firing system according to claim 4, wherein:a conduit is inserted between said second pressure reducing valve and said electromagnetic valve, said conduit storing said low-pressure gas about to enter said electromagnetic valve to drive said firing system.
  • 6. An air gun firing system according to claim 4, wherein:a conduit is inserted between said storage space and said medium-pressure chamber, said conduit storing said medium-pressure gas about to enter said medium-pressure chamber to fire said bullet.
US Referenced Citations (3)
Number Name Date Kind
5967133 Gardner, Jr. Oct 1999 A
6003504 Rice et al. Dec 1999 A
6065460 Lotuaco, III May 2000 A