US3227148A

US3227148A - Gas operated gun

Info

Publication number: US3227148A
Application number: US82077A
Authority: US
Inventors: Theodore W Spack
Original assignee: BENJAMIN AIR RIFLE CO
Current assignee: BENJAMIN AIR RIFLE CO
Priority date: 1961-01-11
Filing date: 1961-01-11
Publication date: 1966-01-04
Anticipated expiration: 1983-01-04

Description

Jan. 4,l 1966 T. w. sPAcK 3,227,148

GAS OPERATED GUN Filed Jan. 1l, 1961 2 Sheets-Sheet 1 T. W. SPACK GAS OPERATED GUN Jan. 4, 1966 2 Sheets-Sheet 2 Filed Jan. ll. 1961 United States Patent O 3,227,148 GAS OPERATED GUN Theodore W. Spack, Webster Groves, Mo., assignor to Benjamin Air Rifle Company, St. Louis, Mo., a corporation of Missouri Filed Jan. 11, 1961, Ser. No. 82,077 12 Claims. (Cl. 124-11) This invention relates to gas' operated guns in which a compressed gas is applied as the propellant. However, the improvements hereinafter disclosed may in certain respects be applied to other types of guns.

An object of the invention is to provide a gun with a simple and effective safety which prevents the hammer from becoming cocked while the breech is open, thereby assuring complete safety during loading and inspection `of the breech and magazine.

It is also an object of the invention to provide a gas operated gun with means for controlling vand variably setting the power charge availablefor expelling the pellets, and for releasing the gas pressure when desired.

A further object of the invention is to provide auto-l matic pellet feed means and means to control the pellets `in such manner that one pellet at a time is positioned for `valve means and the hammer., The foregoing assembly is suitably mounted upon a hand grip or stock, as the ease may be, in which the trigger mechanism is housed. These and other features of the invention will become `more fully understandable during the course of present- ;ing the following description of the preferred construction,

reference being made tothe accompanying drawings, in which:

FIG. 1 is a side elevational View of a pistol havingy portions .thereof broken away and shown in section; FIG. 2 is a top plan view of the pistol of FIG. 1; FIG. 3 is a greatly enlarged view of a safety device incorporated in the gun of FIG. l, the view being taken `at line 3-3 in said FIG. l;

FIG, 4 is a greatly enlarged and fragmentary `side elevational view showing more of the details of the gun; and

FIG. 5 is a transverse sectional view taken at line 5-5 inFIG. 4.

Referring to FIGS. 1 and 2, the gun 10 has a tubular barrel 11 suitably secured to a hand grip or stock 12 in which the trigger 13 and related mechanism to be described later is operably mounted. The barrel carries a tubular cover 14 in which are housed a shot tube 15 and a magazine tube 16 in communication at the breech 17 of the shot tube 15. A shot follower guide tube' 18 (FIGS. 2 and 5) is positioned adjacent one side of the cover 14 and barrel 11 and is suitably secured to either or both parts. The barrel 11, shot tube cover 14 and guide tube 18 are closely nested in tangential relation (FIGS. 2 and 5) and have their longitudinal axes in parallel relation to form a compact assembly having a` lformed with a threaded forward open end 20 to receive a plug device 21 to be described in more detail. The

chamber 22 at the forward end portion of the barrel is adapted to receive a conventional CO2 cylinder 23, and a bulkhead disc 24 is secured at the inner end of such chamber by a suitable resilient retainer ring element 25. Spaced from the bulkhead 24 is a valve block 26 which is secured in the barrel by a ferrule 27 which extends into the cover 14. The block is formed with an axial passage 28 open at a forward lip 29 and with a radial passage open to the ferrule 27. The space between the valve block 26 and the bulkhead 24 contains a suitable valve element 30 having a seat gasket 31 which seats on the lip 29 and a combined guide and metering pin 32 which slides in the bulkhead 24 and has a loose lit so that gas may freely pass. A spring 33 is mounted on the pin 32 and abuts the bulkhead at one end and the enlarged valve element 30 at its opposite end. The spring 33 acts to hold the seat gasket 31 upon the lip 29 thereby cutting off gas flow to the ferrule tube 27. The valve element 26 is further guided by a hammer strikepin 34 having a bearing sleeve 35 thereover which slides in a bore in the valve block 26. The strike pin 34 projects rearwardly into a` hammer chamber 36in the barrel.

In FIG. l, the rear end of the barrel is closed by a block element 37 held therein by a threaded element 38 which also secured the grip 12 to the barrel 11. The block 37 carries a guide element 39 on which a hammer spring 40 is mounted. Telescoped over the guide element 39 is the hammer 41, and the spring 40 works between the closure block 37 and the inner end of the spring containing bore 42 in the hammer 41. The hammer 41 is formed with an annular groove 43 near its inner end, which groove is adapted to catch on the detent end 44 of a relay lever 45 which is pivotally mounted on a pin 46 in the grip 12. The relay lever 45 is urged in a clockwise direction, as viewed in FIGS. 1 and 4, by a spring arm 47, the opposite end 48 of said spring being fixed against a stop 49 in the grip 12. The relay lever has an actuating arm 50 which is engaged by the arm 51 which is a part of the trigger 13. The trigger is movably mounted on a pin 52 in the grip 12 so that the arrn 51 is movable clockwise to actuate the release arm 51 and is forced m a counter clockwise direction by the relay spring arm 47 acting on the relay. A conventional rotary type trigger safety lock is shown at 53 in the safety position, and need not be described since its function is understood.

There is shown in FIG. 2 a hand operated cocking" slide 54 having the pull handle 55 thereon. The slide is connected to the hammer 41 by the connecting means 56 which operates in a slot (not shown) formed in the side of the barrel 11. This slide 54 is shown inthe cocked position to correspond with the hammer position of FIG. 1, but when the gun is discharged it moves forward under the action of the spring 40 when the relay detent 44 is released from the hammer groove 43 upon actuation of the trigger 13 as is well understood.

With reference to FIG. 4 in particular', the ferrule 27 has its bore in communication with an annular cavity 58 around the breech end 17 of the shot tube 15 and inside the cover 14. The cavity 58 is formed by an annular land 59 at its forward end and by an enlarged end portion 60 at the forward end of the magazine tube 16. 4The cavity is in communication with the breech of the' shot tube 1 5 through radial ports 61 so that gas released at valve port 29 may enter behind the head end 62 of the pellet P first in line. Gas leakage along' the' outside of the shot tube 15 and the magazine tube 16 is prevented by O-

ring seals

63 and 64 respectively. Thus the gas charge is conlined to the discharge of the pellet P from the breech 17.

It has been found that the discharge of the leading pellet P creates a draw or suction effect upon the following pellets in the magazine tube 16 and this reduces the pellet discharge power as well as causes undesirable positioning of subsequent pellets. To overcome this fault the forward end portion 60 of the magazine tube 16 is made slightly smaller in diameter than the internal diameter of the cover 14 for its length from the O-ring seal 64 to the breech 17. This zone of the magazine tube is further provided with one or more axially spaced radially directed series of apertures 65 (two series being shown) which open behind seats 66 of suitable form which retain small O-ring elements 67. A portion of the innermost surfaces of the O-ring elements 67 project into the bore of the magazine tube 16. The exposed surfaces form retainers for the following pellets P so that these pellets are held in proper position and do not become displaced during the firing of the leading pellet P. The O-ring seals 67 also act to prevent or reduce the reverse escape of the gas charge so that a full gas charge is available. The elfectiveness of the O-ring seals 67 is greatly increased by providing a passage 68-along the outer side of the magazine tube end portion 60, which passage 68 communicates with the apertures 65 and supplies gas under pressure to the O-ring seals 67 to compress the same more tightly about the pellets P at the moment of firing. Once the gas charge is exhausted, the seals 67 relax and allow relatively free displacement of the pellets for the next shot.

In combination with the foregoing novel improvement,

.the mechanism includes a positive mechanical shot or pellet stop which takes the form of a stop finger 70, movable into the reduced waist zone of the pellet next in line for entry into the breech. The finger 70 (FIGS.

v1 and 4) is actuated by a slide 71 which is movable in a slide passage 72 formed in the valve block 26 behind the ferrule position. The slide has an enlarged slot 73 therein so that it may straddle the pin 34 and its bearing sleeve 35 and move freely through the passage 72. A suitable spring 74 urges the slide in a direction to hold the finger 70 fully withdrawn from the magazine tube bore (FIG. 1). The opposite end 75 of the slide 71 .projects into abutment with the end portion 50 of the relay 45 adjacent the trigger arm 51 so as to be responsive to actuation of the trigger when firing the gun. It is understood that as the trigger is pulled, the slide 71 lis moved upwardly to raise the stop finger 70 so that at the instant of hammer (dotted line position of detent 44) -release the finger 70 (dotted line position) has fixed the pellet P next in line to the one about to be discharged.

`This action may be accomplished only when the safety is rotated to the off position (dotted outline in FIG. 4).

In FIGS. 1, 3 and 2 there has been shown a novel device for rendering the gun safe from accidental discharge during loading pellets into the magazine 16. This device includes a plate 77 having a circular base portion l78 which fits over the closure block 37 of the barrel 11 `and is pivotally secured thereto by threaded element 79 which is positioned in the axial center of the block 37.

.The base portion 78 supports a circularly shaped closure portion 80 which is normally positioned to cover the inlet end 81 of the magazine tube 16, and a rear gun sight plate 82 is carried by the portion 80. The sight plate y82 is suitably notched at 83 to cooperate with the front sight 84 (FIG. 1). The safety plate device 77 is releasably held in its normal position of FIG. l by a detent element 85 slidably mounted in the block 37 at a position eccentric to the center pivot element 79. The detent velement85 normally seats in a recess 86 in the inner face .of the plate portion 78 under the action of a spring 87 behind the detent, and the detent is guided by an extension pin 89 which projects through the block 37 and into the hammer-chamber 36. When the plate device 77 is in its normal position the detent 85 is forced into the recess 86 and the pin 89 is sufiiciently withdrawn from the chamber 36 so as not to interfere with the desired cocking stroke of the hammer 41. However, when the device is swung laterally about its pivot 79 the detent is cammed inwardly by the relief contour 90 on the recess 86 so that the pin 89 is pushed into the chamber 36 and prevents the hammer 41 from being drawn rearwardly sufficiently far to be cocked on the detent 44 of the trigger relay lever 45. The swinging of the device 77 opens the magazine tube 16 for reloading, but if the hammer is in its cocked position the device cannot be moved since the detent is unable to move due to interference between the pin 89 and the hammer 41. Therefore, the hammer must first be released from its cocking detent 44.

Once the device 77 is free to be swung aside, the magazine tube 16 is accessible. It then is necessary to withdraw the follower plunger 90 from the tube 16 to reload. The plunger 90 is connected by arm 91 to a handle 92 (FIG. 2) which moves along the side of the cover 14, the arm 91 being movable in a suitable slot (not shown) in the side of the cover adjacent the guide 18. The handle 92 is connected to a guide rod 93 in the guide 18 and this rod is spring loaded by an elongated spiral spring 94 (FIG. 5) to pull the rod 93 rightwardly as viewed in FIG. 2, the spring being housed in the guide 18. When the follower plunger 90 has cleared the outer end of the magazine tube 16 it may be rotated sidewise to leave the tube 16 unobstructed for loading pellets P.

Turning now to FIG. 1 the plug device 21 threaded into the barrel 11 at 20 comprises a body 95 suitably formed to provide an annular seat for an O-ring seal 96. The body has an axial bore 97 to receive a threaded stem 98, the stem having an enlarged inner end 99 in the bore 97 with an O-ring seal therein. The outer end of the stem 98 carries a power adjusting knob 100 which is locked to the stem by a set screw 101. The stern is formed with a bore to slidably mount a pressure relief valve 102 located in the enlarged bore 97 and adapted to engage the adjacent end of the CO2 cylinder 23. The valve 102 is actuated by a button 103 housed in the outer end of the knob 100, said button moving the reduced diameter end 98 against the valve 102. The relief valve 102 is a plug of nylon or other suitable material which when forced against the end 98 of the stem seals the gas against leakage along the stem 104 connecting the valve and button 103. Variations in adjustment are obtained by setting the end 99 of the stem 98 more inwardly or outwardly from the position shown in FIG. 1. This setting determines the position of the valve 102 which normally is pushed by the gas pressure tightly against the end 99. The resulting setting of valve 102 determines the position of the CO2 cylinder in chamber 22 and therefore locates the distance between the mouth 105 of the CO2 cylinder and the piercing end 106 of the valve stern 32. A lesser charge of gas to the breech 17 is obtained by shortening the travel of the stem 32 to cause the end 106 to abut the mouth 105 of the CO2 cylinder. The abutment does not displace the cylinder since it is held by the relief valve 102 so that the valve 30 is only open for a short time. A greater charge of gas is obtained by setting the end 99 farther back in the body 95 so that the relief valve 102 is farther back and spaces the CO2 cylinder farther from the stern 32 so that the valve 30 is open for a longer time interval. Should it be necessary to relieve the gas pressure from chamber 22, the button 103 is pushed in to move relief valve 102 away from its seat on the end 99 of stem 98. This action allows the gas to bleed out along the stem 104 to atmosphere until it is safe to remove the device 21.

While the foregoing has described a preferred construction illustrated in the accompanying drawings, the arrangement of parts and components may be varied or modified without departing from the principles of the invention. No unnecessary limitation is to be inferred except such as may be required by the claims appended hereto.

What is claimed is:

`1. .In a gun assembly, a hand grip, an elongated tubular i rel and cover, and shot follower means operably carried by said guide tube and having a member extending into said magazine tube from said one open end.

2. In a gun assembly, a hand grip, an elongated barrel secured to said grip and providing a plurality of spaces for operating mechanism, an elongated cover disposed alongside of and secured to said barrel in parallel relation and at the side of said barrel opposite said grip, a shot tube and a magazine tube carried in said cover in axial alignment, a shot follower member movably mounted in said magazine tube, an elongated guide tube disposed in parallel relation along side said barrel and cover with one end adjacent the location of said magazine tube, and follower means guided by and movable in said guide tube and having a connection withsaid shot follower.

3. In a gas operated gun, a barrel member having a gas supply chamber adjacent one end and a hammer chamber adjacent the opposite end, a valve block member separating said chambers and having a seat and a gas ilow passage extending from the seat through a side of said barrel to a gas outlet, a valve element normally closing said seat to shut off the ilow of gas, a spring loaded valve actuating hammer member in said hammer chamber, trigger mechanism on the gun including a lever releasably engaging said hammer member in cocked position, a shot tube on said barrel having a breach end adjacent said gas outlet, a magazine for propellable shot communicating with said breach end to feed shot into said breach end one at a time, and shot stop means in said gun including a resilient element carried by said magazine adjacent said breach end to engage a propellable shot in advance of movement into said shot tube breach end an element operably carried by said barrel member and having a finger thereon extended into said magazine in response to said trigger mechanism to release said hammer member to intercept the shot next following that one in said breach end of the shot tube.

4. The gas operated gun set forth in claim 3, wherein said shot tube and magazine are arranged in axial alignment, and including a cover for said shot tube and magazine, and seal means is engaged between said cover and each of said shot tube and magazine on either side of said breach to prevent escape of gas through said cover.

5. The gas operated gun set forth in claim 3, wherein said magazine adjacent to said breach end of said shot tube is formed with an internal seat and said resilient element is disposed in said seat in position to engage a propellable shot and impede its movement during discharge of a shot in said breach end, and said magazine is formed with a passage opening at said internal seat to deliver gas to said seat to urge said element more tightly into engagement with a propellable shot.

6. The gas operated gun set forth in claim 5, including a cover enclosing said shot tube and magazine, seals between said cover and shot tube and magazine, said seals being spaced apart on either side of said breach end to prevent escape of gas from said breach end, said resilient element being responsive to the ow of gas directed by said cover to said magazine passage to expel a shot from said breach end to close upon a `shot in said magazine adjacent thereto and hold the same against displacement.

'7. In a gas operated gun, a barrel, a valve block secured in said barrel and having a gas flow passage therein formed with an inlet seat, a valve for controlling said inlet including an actuating stern extending past said d valve block into the barrel, a spring loaded hammer member movably carried in said barrel and operable between a cocked position and a position to strike said actuating stem and unseat said valve, means closing said barrel and forming an abutment for said hammer in its cocked position, trigger mechnism in the gun operable to retain said hammer member in its cocked position, and safety means on the gun to prevent cooking of said hammer member comprising a pin movably mounted in said barrel closing and hammer abutment means and having one end movable into said barrel to hold said hammer member out of its cocked position, the opposite end of said pin movable out of said closing means, and a member movable on ='said barrel closing and hammer abutment means and having a recess therein which is positionable to receive the opposite end of said pin and permit cooking of said hammer member, movement of said last member out of its iirst said position placing the gun on safety.

8. In a gas operated gun, a grip, trigger mechanism 0perable in said grip, a barrel on said grip having a hammer space adjacent said grip, a gas control valve assembly in said barrel defining one end of the hammer space, a valve in said assembly having a stem projecting into said space, a member in the end of said barrel closing said space, hammer means reciprocably mounted in said space to move from a cocked position adjacent said closing member to strike said valve stem, said hammer being retained in its cocked position by said trigger mechanism, and means to prevent said hammer reaching its cocked position including an abutment pin element movable through said closing means between a position with one end extending into said space to stop movement of said hammer means into cocked position and a position with the opposite end projecting outwardly of said closing means and said one end retracted from said space, and abutment pin element control means at the exterior of said barrel in operable connection with said element, said control means comprising a member pivoted on said closing means and manually movable between said positions, said member having a recess cam therein receiving the opposite end of said abutment pin element in the second named position of said abutment pin element.

9. A gas operated gun comprising, a barrel, a cover and a guide arranged in a cluster, said barrel and cover having gas ow communication, a source of gas under pressure in said barrel, valve means in said barrel controlling gas flow to said cover, a shot tube and a magazine in said cover arranged in communication with each other at a breach adjacent the gas flow communiaction to said cover, seal means in said cover on either side of said breach to confine the gas therein, propellable shot in said magazine, other seal means in said magazine engaging at least one of said shot to form therewith a plug to resist gas flow reversely into said magazine, a shot follower in said magazine behind the shot and spring loaded means in said guide connected to said shot follower to cooperate in urging said shot toward the breach, a valve control hammer in said barrel movable from a cocked position to open said valve, and safety means including a closure for the magazine having a normal closed position and movable to one side to open the same for loading shot and an element movable in response to said closure movement to one side to block said hammer from reaching its cocked position while the magazine is open.

10. The gun set forth in claim 9, wherein said other seal means is in communication with the gas flow into said cover and contracts about the shot with each valve opening reaction to said hammer.

11. The gun set forth in claim 9, wherein said shot follower is removable from said magazine and is supported by said spring loaded means, and said safety means in its normal position preventing said shot follower from being removed.

12. The gun set forth in claim 9, wherein said closure of the safety means is formed with a sighting opening,

and said cover carries a cooperating sight remote from said magazine.

References Cited by the Examiner UNITED STATES PATENTS Burgher.

Falk.

Lefever 124-30 Straub 124-11 Johnson 124-52 X Foster 124-52 X Gale 124-11 Martin 124-11 Hamrick 124-30 Cardin et al. 124-11 RICHARD C. PINKHAM, Primary Examiner.

JAMES W. LOVE, Examiner.

Claims

1. IN A GUN ASSEMBLY, A HAND GRIP, AN ELONGATED TUBULAR BARREL MOUNTED ON SAID GRIP AND PROVIDING AXIALLY ALIGNED CHAMBERS FOR OPERATING MECHANISM, AN ELONGATED TUBULAR COVER MOUNTED IN PARALLEL RELATION AND FIXED ON SAID BARREL OPPOSITE TO SAID GRIP, A SHOT MAGAZINE TUBE IN SAID COVER AND OPENING FROM ONE END THEREOF, AN ELONGATED GUIDE TUBE MOUNTED IN PARALLEL RELATION TO SAID BARREL, MAGAZINE