Abstract:
A pressurized gas powered rapid fire ball gun for propelling ball projectiles automatically or semi-automatically. An air chamber formed in a housing which slidably supports an air control spool for longitudinal translation, stores a pressurized gas charge within an internal air reservoir which enhances ball projectile propulsion when simultaneously combined with pressurized gas from a separate source and fed into a firing chamber adjacent the elongated cylindrical barrel at each firing.

Description:
BACKGROUND OF THE INVENTION 
     1. Scope of Invention 
     This invention relates generally to pneumatic or pressurized gas ball firing guns of the semi-automatic or automatic firing sequencing type, and more particularly to such a ball gun for propelling ball projectiles similar in size to well known paint balls in an amusement park setting and the like. 
     2. Prior Art 
     Semi-automatic and automatic type pneumatic or pressurized gas actuated guns for projecting ball shaped projectiles such as ping-pong balls, paint balls and the like are well known. One such device is disclosed in U.S. Pat. No. 5,063,904 invented by Farrell which teaches a pneumatic gun dependent upon a compressed power spring acting from a cocked position to impact on a primary valve assembly and thereby to release compressed gas from a line source for propelling a spherical projectile from the gun. This arrangement for triggering the firing of a mechanism in releasing a charge of compressed gas from a separate compressed gas source is somewhat complex and, despite that complexity, the efficiency or velocity of projectile propulsion is entirely dependent upon the pressure and volume of compressed gas delivered from the compressed gas source. As the ball projectile is not sealed, further losses in gas pressure at firing are also present. 
     Steer in U.S. Pat. No. 5,343,849 has also developed a rapid fire ball gun which includes a self-contained pressurized air vessel and an air pump apparently for recharging. A supply of compressible foam balls are loaded in end-to-end relation into an elongated cylindrical barrel and then discharged one at a time, the forward most ball being discharged one at a time. 
     A number of other devices somewhat more remote in structural and operational nature are disclosed in the following U.S. prior art: 
     
         ______________________________________Tippmann       4,819,609Amron          5,396,877Robinson       5,333,594Glass et al.   3,868,113Dobbins, et al.          4,936,282Brovelli       5,448,984Ekstrom        5,161,516Webber         5,267,549Lee            5,285,765Hampton        5,431,410Arad           5,377,655Scott          5,494,024Lewinski, et al.          5,377,656De Freitas     3,572,309Petrick, Sr.   4,112,911______________________________________ 
    
     The present invention discloses an automatic or semi-automatic pressurized gas ball gun for propelling spherical paint ball sized, preferably hollow objects and the like. The device holds a supply of ball projectiles which are automatically gravity fed into a chamber positioned between the housing and cylindrical barrel. Pressurized gas from a separate source is fed into the housing and is utilized for accumulation within an air reservoir and for routing throughout passageways in the housing so as to controlledly drive a separate air control spool from its at-rest position to a firing position whereupon the compressed air charge in the air reservoir combines with the line compressed gas pressure from the source to propel each ball projectile. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention is directed to a pressurized gas powered rapid fire ball gun for propelling ball projectiles automatically or semi-automatically. An air chamber formed in a housing which slidably supports an air control spool for longitudinal translation, stores a pressurized gas charge which enhances ball projectile propulsion when simultaneously combined with pressurized gas from a separate source and fed into a firing chamber adjacent the elongated cylindrical barrel at each firing. 
     It is therefore an object of this invention to provide an improved pressurized gas powered ball gun for firing ball projectiles in automatic or semi-automatic fashion. 
     It is another object of this invention to provide a pressurized gas powered ball gun for firing projectiles which includes an additional air reservoir which holds a pressurized gas charge which combines with pressurized gas from a separate supply for enhanced propulsion of ball projectiles. 
     It is still another object of this invention to utilize electronic trigger and pressurized gas flow control means for actuation. 
     It is still another object of this invention to provide a pressurized gas ball gun for firing projectiles with the increased firing efficiency by insuring that virtually all of the pressurized gas utilized to fire each ball projectile is expelled through the barrel and not elsewhere lost. 
     It is yet another object of this invention to provide a pressurized gas powered ball gun for firing ball projectiles which will operate on very low pressurized gas pressure in the range of as low as about 55 p.s.i. 
     In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a bottom plan exploded view of the housing assembly 10 of the present invention. 
     FIG. 2 is a side elevation exploded view of the assembled housing 10 and electronically controlled air flow solenoid and inlet fitting 
     FIG. 3 is a top plan exploded view of a ball projectile chamber. 
     FIG. 4 is an side elevation exploded view of FIG. 3 and including a portion of a ball feed mechanism attached to the chamber. 
     FIG. 5 is a side elevation exploded view of a ball chamber, ball loader tube and barrel. 
     FIG. 6 is a side elevation exploded view of the entire invention. 
     FIG. 7 is a side elevation partially broken view of the housing 12. 
     FIG. 8 is a left end elevation view of FIG. 7. 
     FIG. 9 is a right end elevation view of FIG. 7. 
     FIG. 10 is a bottom plan view of FIG. 7. 
     FIG. 11 is a right end elevation view of FIG. 10. 
     FIG. 12 is a side elevation view of an air control spool. 
     FIG. 13 is an end elevation view of FIG. 12. 
     FIG. 14 is a side elevation view of an air control sleeve. 
     FIG. 15 is an end elevation view of FIG. 14. 
     FIG. 16 is a side elevation view of an air piston sleeve. 
     FIG. 17 is an end elevation view of FIG. 16. 
     FIG. 18 is a side elevation view of a loader tube spacer. 
     FIG. 19 is a top plan view of FIG. 18. 
     FIG. 20 is a side elevation view of a ball loader tube. 
     FIG. 21 is a top plan view of FIG. 20. 
     FIG. 22 is a side elevation section view of the housing assembly 10 absent the air control spool return spring, ball chamber and ball loader mechanism showing the arrangement in at at-rest position and showing a bottom plan view of an air control solenoid mounting pad 46. 
     FIG. 23 is a view similar to FIG. 22 showing the mechanism in a firing position. 
     FIG. 24 is a view similar to FIG. 22 showing the mechanism partially returned from firing position. 
     FIG. 25 is a side elevation view of the ball chamber. 
     FIG. 26 is a bottom plan view of FIG. 25. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, an exploded view of an air control housing assembly is shown generally at numeral 10. This assembly 10 includes a housing 12 which is shown in detail in FIGS. 7 to 11. The housing 12 is of machined aluminum stock, but could be formed of die cast metal or injection molded plastic material. 
     The housing 12 is elongated and includes a substantially cylindrical bore 102 formed therethrough. An internal thread 128 is formed at a closed end of the housing 12 which is sized to receive an end plug 14 seen in FIG. 1. The end plug 14 receives an electronic trigger mechanism which includes trigger switch 80, collar 82 and nut 84 as seen in FIG. 6. By this arrangement, this entire end of housing assembly 10 is sealed closed. 
     An enlarged cylindrical cavity 108 is formed adjacent the other externally threaded end 124 of housing 12. This enlarged cylindrical cavity 108 will form one side of an air reservoir to be described herebelow. 
     A pressure fitting 48 shown in FIG. 2 theadably engages into internally threaded inlet 104 of housing 12 to provide a means for connecting a separate supply of pressurized gas (not shown) to the housing 12. Pressurized gas which is introduced into inlet 104 is fed by elongated internal passageway 106 into fluid communication with annular cavity 108 at one end 110 of passageway 106 and in an opposite direction to connect with pressure port 120 formed into a flat air control solenoid mounting pad 46. 
     A bypass port 118 extends from the mounting pad 46 to connect with longitudinal passageway 116 which, in turn, connects with vent 112. A sealing grommet 114 which mateably engages against a closed portion of the mounting surface of air control solenoid 44 provides for unsealed, but inhibited discharge of pressurized gas which is directed into the vent 112. A cylinder port 122 extends from mounting pad 46 directly into the air piston chamber 134 as best seen in FIG. 22. 
     An air control sleeve 16 is shown separately in FIGS. 14 and 15 and in operable position within housing 12 in FIGS. 22 to 24. The air control sleeve 16 includes a cylindrical longitudinal bore 21 therethrough and radially extending evenly spaced ports 18. Sealing grooves 17 and 19 are provided adjacent each end thereof for receiving o-ring seals as shown in FIGS. 22 to 24. The air control sleeve 16 is positioned stationary within bore 112 of housing 12 so that a central portion of slightly smaller diameter than the end thereof is positioned in alignment with annular cavity 108. By this arrangement, an annular shaped generally cylindrical air reservoir 109 is defined therebetween. Thus, whenever pressurized gas is being introduced into inlet 104, pressurized gas at approximate equal pressure freely flowing through clearance 132 is thereby always available for accumulation within air reservoir 109. 
     A stationary air piston sleeve 32 as best seen separately in FIGS. 16 and 17 and in exploded view in FIG. 1 and FIGS. 22 to 24 includes a cylindrical bore 37 formed therethrough and an o-ring groove 35 formed adjacent one end thereof and an enlarged cylindrical surface 34 formed at the other end thereof. An air passageway 36 is formed through a central portion of air piston sleeve 32 which extends through to cylindrical bore 37. The air piston sleeve 32 is positioned stationary in close proximity to end plug 14 with an air gap or head space 130 therebetween as best seen in FIG. 22. 
     The only moveable component within housing assembly 10 is an air control spool 20 as shown separately in FIGS. 12 and 13 and in the exploded view of FIG. 1 and in FIGS. 22 to 24. This air control spool 20 is formed of machined or die injected plastic material such as DELRIN for lightness and durability and is elongated and cylindrical in nature having a longitudinal passageway 21 formed centrally therethrough. About one half of the length of this air control spool 20 defines a continuous cylindrical surface 22 and also defines a maximum diameter of the spool 20. Sealing grooves 23 for receiving sealing o-rings are provided on either side of radially extending ports 26 which extend into passageway 21. A smaller outer cylindrical portion 24 is sized in outside diameter and length to fit and extend within return coil spring 38 shown in FIG. 1 and spring chamber 134 in FIG. 22. A second and smaller set of radially extending ports 28 having sealing grooves 27 on either side thereof for receiving o-rings are positioned at a mid point of the smaller cylindrical surface 24. An internal thread 29 sealingly receives threaded fastener 42 shown in FIG. 1 which retains an air controlled spool piston 40 connected to the corresponding end of the air control spool 20. 
     As seen in FIGS. 1 and 22 to 24, the air control spool 20 is positioned and is somewhat coextensive within housing 12. At one end of housing 12, the air control spool piston 40 slidably engages in sealing fashion within the cylindrical bore 37 of the air piston sleeve 32 and cylindrical surface 22 slidably engages within cylindrical bore 21 of the air control sleeve 16 with the o-rings within sealing grooves 23 forming a gas seal on either side of radial ports 26. 
     A ball chamber 50 as seen in FIGS. 3, 4, 25 and 26 is connected onto the open end of housing 12 and is self-aligning with tab 56 interengaging with one notch 126 of housing 12. A threaded nut 58 retains this arrangement as best seen in FIGS. 22 to 24. An air control seal spacer 70 fitted within cylindrical bore 55 slidably engages around cylindrical surface 22 of the air control spool 20. O-rings disposed at each end of the air control seal spacer 70 insure sealed slidability of the mating surfaces therebetween. 
     A ball loader tube 64 and spacer 60 are connected as best seen in FIGS. 22 to 24 to a circular aperture 52 formed centrally through a side wall of the chamber 50 and extend into longitudinal central bore 53 as seen in FIGS. 25 and 26. The inner bore 65 of the ball loader tube 64 is sized to allow ball projectiles B to freely drop downwardly by gravity therethrough. By this arrangement, a plurality of ball projectiles B may be stored in ready-to-load position within the ball loader tube 64 and an upward tubular extension thereof (not shown). By this arrangement, a ball projectile B1 is always in position within the central cylindrical bore 53 of chamber 50 in ready-to-fire position. 
     The barrel 72 is permanently and sealably fitted at surface 74 into cylindrical bore 61 of chamber 50. Obviously, the barrel 72 is sized in inside diameter to minimize clearance with ball projectile B and yet allow each ball projectile B to be efficiently fired therethrough. Clearance is typically in the range of 0.012&#34;. 
     As previously briefly discussed, an electronically regulated air control solenoid 44 is connected onto mounting pad 46 of housing 12. As will be explained in more detail below, this air control solenoid 44 directs air flow between passageways 118, 120 and 122 formed into mounting pad 46. This air control solenoid 44 is commercially available under the trademark MAC, Model No. 35A-BOO-DACE-1BA manufactured in Wixom, Mich. Liege, Belgium and Auckland, New Zealand. The electronic trigger actuator 80 is supplied by McMaster-Carr, part No. 7397K25. 
     The entire air control housing assembly 10 and barrel 72 are connected to and supported on a swivel mount base shown generally at 86 in FIG. 6. This swivel base 86 includes a support tube 88 connected at 90 with mounting flange 92 and handle 94 also being provided to facilitate mounting and use in an amusement theme park or ride. 
     MODE OF OPERATION 
     Referring particularly to FIGS. 22 to 24, the mode of operation during each firing sequence is there shown. Note that the return spring 38 shown in FIG. 1 is deleted for clarity. With pressurized gas from a separate source (not shown) connected to inlet 104, pressurized gas enters into air reservoir 109 and is retained in sealed relationship between cavity 108 and the outer surfaces of the air control sleeve 16 and surface 22 of the air control spool 20. 
     As seen in FIG. 22, the housing assembly 10 is shown at the beginning of a firing sequence. One ball projectile B1 has been fed by gravity into firing position with the distal end 31 of the air control spool 20 in contact therewith. When the electronic trigger 80 shown in FIG. 6 is actuated, the air control solenoid 44, which continuously receives pressurized gas thereinto through pressure port 120 via longitudinal passageway 106 in FIG. 7 as previously described, transfers air pressure into the cylinder port 122 which immediately delivers pressurized gas into head space 130 acting against the head of the air control spool piston 40 to begin to move the entire air control spool 20 in the direction of the arrow. 
     As seen in FIG. 23, at the instant of firing, the ball projectile B1 in firing position, has been urged by the distal end 31 of the air control spool 20 into a restrained sealing arrangement with o-ring 140. Note that o-ring 142 is sealingly engaged around the distal portion of surface 22. It is at this momentary firing position that the air reservoir 109 which has previously been charged with pressurized gas equal in pressure to that of line pressure entering into inlet 104 is vented into radial vents 26 of the air control spool 20 which momentarily align with the radial vents 18 of the air control spool 16. In this position, the longitudinal bore 21 being previously sealed, receives the entire accumulated gas charge within gas reservoir 109, along with the pressurized gas available at inlet 104 from the pressurized gas source. This entire pressurized gas charge is forced against the ball projectile B1 to propel it from the barrel 72. 
     Note that, because the distal end of the air control spool 20 is sealed within oaring 142 and the ball projectile B1 is sealed against o-ring 140, virtually all of this combined pressurized gas charge is utilized efficiently to propel the ball projectile B1 and is discharged from the distal end of barrel 72. 
     In FIG. 24, the air control spool 20 is being returned to the at-rest position in the direction of the arrow. The air control solenoid 44 has additionally delivered pressurized gas into bypass port 118 which provides pressurized gas into spring chamber portion 134a to somewhat cushion the movement of the air control spool 20, by sealing this air chamber portion 134a as o-ring 136 passes by and seals off port 36 of the air piston sleeve 32. 
     While the instant invention has been shown and described herein in what are conceived to be the most practical and preferred embodiments, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein, but is to be afforded the full scope of the claims so as to embrace any and all equivalent apparatus and articles.