US 3855990 A
There is herein disclosed an air gun storage chamber valve and sealing arrangement comprising a single piece of tubing divided into a compression chamber and a storage chamber by a radially inwardly extending abutment wall portion of the tubing with a solid annular plate member axially slidably mounted in the storage chamber for movement relative to the abutment wall while being abuttingly associated with a solid annular sealing member pressed thereagainst by a compression spring in the storage chamber, there being an air passage from the compression chamber to the storage chamber around the periphery of the plate member and the sealing member along the wall of the tubing with the sealing member having a resilient deflectable skirt engagable with the tubing to open and close the passage solely by pressure differential between the chambers.
Description (OCR text may contain errors)
United States Patent 1191 Joyce et al.
 Dec. 24, 1974 AIR GUN VALVE APPARATUS ASSEMBLY  Inventors: Ronald W. Joyce, Springdale; Ross T. Dozier, Rogers, both of Ark.
 Assignee: Victor Comptometer Corporation,
22 Filed: Oct. 10, 1973 21 Appl. No.: 405,134
 US. Cl 124/13 A, 137/5l6.29, 417/566  Int. Cl...... F4lb 11/00, F41f 1/04, Fl6k 15/14  Field of Search 124/13 A; 137/5l6.25, 516.27,
 0 References Cited UNITED STATES PATENTS 695,025 3/1902 Benjamin 124 13 A Primary ExaminerRichard C. Pinkham Assistant ExaminerR. T. Stouffer Attorney, Agent, or Firm-Bruce G. Klaas  ABSTRACT There is herein disclosed an air gun storage chamber valve and sealing arrangement comprising a single piece of tubing divided into a compression chamber and a storage chamber by a radially inwardly extending abutment wall portion of the tubing with a solid annular plate' member axially slidably mounted in the storage chamber for movement relative to the abutment wall while being abuttingly associated with a 'solid annular sealing member pressed thereagainst by a compression spring in the storage chamber, there being an air passage from the compression chamber to the storage chamber around the periphery of the plate member and the sealing member along the wall of the tubing with the sealing member having a resilient deflectable skirt engagable with the tubing to open and close the passage solely by pressure differential between the chambers.
10 Claims, 2 Drawing Figures 56 '32 sa so/ a?" 1 I I l r L 1 l 54 aa /2 52 86 94 i f I Y 5 .90 22 l I v 42 l 36 92 1 AIR GUN VALVE APPARATUS ASSEMBLY BACKGROUND OF THE INVENTION THE DRAWING A presently preferred illustrative embodiment of the inventive concepts is shown in the accompanying drawing in which:
FIG. 1 is a partial sectional view of air gun storage chamber apparatus showing valve apparatus in a closed position; and,
FIG. 2 is an enlarged partial sectional view of the apparatus of FIG. 1 showing the valve apparatus in an open position.
DETAILED DESCRIPTION Referring to the drawing, an elongated tubular member of cylindrical cross-section is fixedly mounted in the receiver frame 12 of an air gun. An abutment means in the form of shoulder 14 is integrally formed in the wall of member 10 and extends circumferentially 360 to effectively dividethe member 10 into a first elongated cylindrical tubular means providing a variable volume air compression chamber 16 and a second elongated tubular means providing a compressed air storage chamber 18. The shoulder 14 also effectively defines a relatively large central connecting air passage therebetween. Acylindrical portion 20 of a release valve-storage chamber means 22 extends into the member 10 in close-fitting relationship therewith and provides a storage chamber cavity portion 24 through which compressed air may be selectively delivered to the firing chamber of the air gun by actuation of a trigger operated release valve mechanism as is well known in the art. A piston member 26 is reciprocably operable in the compression chamber between a retracted maximum volume position (not shown) and an extended minimum volume position, FIG. 2, to compress and force air into the storage chamber as indicated by the arrows. As disclosed in the prior application, the piston member 26 is connected to a piston rod (not shown) by a lost motion connection (not shown) and has a resilient cushion (not shown) between the piston and the piston rod to cause the piston member 26 to fully seat on the abutment means 14 in the extended position.
The present invention comprises valve and sealing means which permitsflow of air from the compression chamber to the storage chamber and then holds and seals the compressed air in the storage chamber until the compressed air is selectively released for firing the air gun. To this end, a solid non-perforate plate means 30 in the form of a cylindrical plate member, having a cylindrical peripheral portion 32 and a grooved peripheral portion 34 which are of similar contour to the inside peripheral surface of the storage chamber and the peripheral surface of shoulder 14, respectively, is relatively loosely slidably mounted in the storage chamber next adjacent the shoulder 14 for movement between a closed position, FIG. 1, whereat the grooved peripheral portion 34 is seated against the corresponding portion of shoulder 14 and an open position, FIG. 2, lo-
2 cated axially inwardly in the storage chamber in spaced relationship to the shoulder 14. The outside diameter of plate 30 is sufficiently less than the inside diameter of tube 10, e.g. .007 inches, so as to provide air passage means 35 therebetween as illustratively'shown in FIG.
2. It has been found to be desirable to use a metallic material of good wearing characteristics, such .as a brass or zinc alloy, for plate 30. A flat transverse abutment surface 36 on plate 30 faces the compression chamber and may engage a corresponding transverse abutment surface 38 on piston member 26 at the end of a compression stroke. A valve cavity 40 is provided on the opposite side of plate 30 and includes a flat-cylindrical central portion 42 radially terminating in an adjacent pair of reverse curved surfaces 44, 46.
A sealing means 50 abuts the plate member 30 and comprises a solid non-perforate generally cylindrical molded rubber-like member having a body portion including an axially protruding sidewall portion 52 with a flat transverse cylindrical abutment surface 54 and double curved peripheral abutment surfaces 56, 58 dimensioned to be matingly received in the valve cavity 40 of plate 30. An axially and radially extending resilient flexible deflectable tapered skirt portion 6 0 is provided on the outer periphery of the valve member with an intermediate portion 62 of substantially less diameter than the inside diameter of tube member 10 and a terminal portion 64 of normally greater diameter than the inside diameter of the tube member 10 so as to be resiliently inwardly deflected thereby and compressibly slidably engaged therewith while beingv radially inwardly flexible relative thereto to permit compressed air to flow from passage 35 into the storage chamber as illustrated in FIG. 2. A reduced diameter axially extending cylindrical valve body portion 65 defines a cylindrical spring and air cavity 66 and a cylindrical spring support surface 68. A transverse cylindrical spring abutment surface 69 extends between the skirt portion 60 and the body portion 65. A suitable material for member 50 is Minnesota Rubber Co. Compound No. 446A. a
A spring means 70 in the form of a coiled wiretype compression spring has an inside' diameter slightly larger than the diameter of surface 68 so as to .be slidably received thereabout with the end coil 72 of the spring abutting surface 69 in general radial and axial alignment with the outer periphery of wall portion 54 adjacent curved surfaces 44, 46, 56, 58 to insure good seating engagement therebetween.
A ring means 80, made of relatively high strength I rigid plastic material, such as Noryl or Delrin, is closely slidably mounted in the tube member 10 by a cylindrical peripheral portion 82. A cylindrical curved spring seat 84 abuttingly receives spring end coil 86 and a generally oppositely aligned cylindrical transverse abutment surface 88 is held against a corresponding end surface of the valve block 20 with a central cylindrical storage chamber cavity portion 90 in member in general alignment with corresponding storage chamber cavity portion 24. The diameter of chamber portion is somewhat smaller than the outside diameter of valve body portion 65 so as to provide a shoulder seat 92 therefor and a number of tapered passages 94, 96, 98
are provided around the seat 92 to insure free flow of compressed air into the storage chamber shouldthe end wall 100 of body portion 65 ever move into engagement with seat 92. An annular recess 102 is provided on the periphery of ring member 80 and defined by an axially extending annular surface 103 and a radially extending annular surface 104 which define an enclosed annular groove in conjunction with the adjacent portions of the tubular member and the side surface of block means 20. An elastomeric O-ring member 105 having a normal diameter greater than the spacing between side wall 104 of the groove 102 and the end wall 108 of valve block when surface 88 abuts the end wall 108 is mounted, in groove 102 and compressed therein by axially directed spring forces applied through the ring 80 and thus forcibly sealably engaged with the confining groove surfaces to seal the joint between the tube member 10 and the valve block portion 20.
In operation, the valve and sealing apparatus will normally be in the positions shown in FIG. 1 with spring means 70 exerting an axially directed force on valve member 50 and on plate 30 causing engagement of curved plate surface 34 with similarly curved shoulder 14 of the tube member 10. Whenever the pressure in storage chamber 18 is the same or exceeds the pressure in compression chamber 16, the outer portion 64 of the resilient flexible skirt 60 compressibly sealingly engages the inner surface of the tube member 10 and air pressure in the cavity 66 of the storage chamber will'be effective on the inner surface 110 of the skirt to maintain the sealing engagement. The spring is also effective at all times to maintain the seal provided by O-ring 105. When piston 26 is actuated to the extended position of FIG. 2, as by manual or spring operation, the volume of the compression chamber 16 is reduced to compress air therein and the compressed air is effective to overcome the bias of the spring 70 on plate 30 and move the plate and the valve to the open position. The compressed air flows through passage35 around the plate 30 and acts on the outer peripheral surface of the skirt 60 to cause radial inward resilient deflection of the skirt permitting flow of compressed air into the storage chamber 18. As soon as the pressure of the incoming air is equal to or less than the pressure of the air in the storage chamber, the skirt portion 64 will again sealingly engage the inside wall of the tube member 10. The arrangement is such that the piston 26 can fully bottom on shoulder 14 and abuttingly engage plate 30 without causing any damage to the valve apparatus. The present arrangement provides excellent sealing characteristics while comprising relatively few parts which are not subject to wear problems of prior arrangements. In addition, the parts are relatively inexpensive to manufacture and are easily assembled due in part to the lack of necessity of maintaining close tolerances. In fact, the major wear area would appear to be the portion 64 of skirt 60 and it may be readily appreciated that wear atthe area is largely compensated for by the resilience of the skirt and the action of the high pressure air thereagainst. The ease of assembly is greatly facilitated by the present arrangement since all of the parts simply slide into the tube member 10 and,
once inserted, are self-aligning with only the cylindrical 1 In an air gun or the like having a variable volume air compression chamber and a piston means operable in the air compression chamber to compress air therein by movement from a retracted maximum volume position to an extended minimum volume position, the invention comprising:
a first elongated tubular means providing said air compression chamber,
a radially inwardly extending abutment means at one end of said compression chamber abuttingly receiving said piston means in the extended position and defining a central outlet passage from said compression chamber,
a second elongated tubular means having a cylindrical inner peripheral surface providing an elongated cylindrical compressed air storage chamber extending axially from and adjacent said abutment means and connected to said compression chamber by said outlet -passage,
an axially movable cylindrical plate means mounted in said storage chamber next adjacent said abutment means and being movable axially in said storage chamberbetween a closed position relative to said outlet passage in abutting engagement with said abutment means and an open position relative to said outlet passage in axially spaced relationship to said abutment means,
said plate means having an abutment surface facing said abutment means and being engagable therewith in the closed position,
said plate means having a cylindrical outer peripheral surface of a diameter less than the inside diameter of said cylindrical inner peripheral surface of said second tubular means to provide first annular peripheral air passage means therebetween connecting said central outlet passage to said storage chamber,
annular sealing means associated'and movable with said plate means having a cylindrical outer peripheral surfaceof a diameter less than the inside diameter of said cylindrical inner peripheral surface of said second tubular meansto provide second annular peripheral air passage means therebetween connecting said central outlet passage to said storage chamber and including a resiliently deflectable skirt portion having a normal outside diameter greater than the diameter of said storage chamber and normally resiliently compressibly engagable with said second tubular means to seal said air passage means when the air pressure in said storage chamber is equal to or exceeds the air pressure in said compression chamber, said skirt portion being resiliently deflectable radially inwardly of and in spaced relationship to said second tubular means when the air pressure in said compression chamber exceeds the air pressure in said storage chamber to connect said air passage means to said storage chamber,
said plate means and said annular sealing means being loosely slidably supported in said storage chamber only by engagement between said cylindrical inner peripheral surface of said second tubular means and said outer peripheral surface of said plate means and said outer peripheral surface of said sealing means, and
spring means in said storage chamber operatively engaged with said plate means and said sealing means to bias said plate means and said sealing means toward the closed position whenever the air pressure in said storage chamber and the force of said spring means are greater than the air pressure in said compression chamber.
2. The invention defined in claim 1 and wherein:
said plate means having an abutment surface facing said central outlet passage and radially aligned therewith,
said piston means having an abutment surface facing said central outlet passage and radially aligned therewith,
a portion of said piston means being movable into abutting engagement with said abutment means and with said abutment surface on said plate means in the extended position of said piston means at or about the closed'position of said plate means, and
said spring means being effective to cushion the force of engagement between said piston means and said plate means.
3. The invention as defined in claim 1 and wherein:
said sealing means having axially extending body portions providing a cylindrical spring seat opposite said recess, and
said spring means comprising a coiled wire type compression spring with the coils of one end of said compression spring havingan inside diameter approximately equal to or larger than the diameter of said spring seat and being mounted circumjacent thereto with the end of said compression spring abutting said body portion opposite said recess.
5. The invention as defined in claim 4 and further comprising:
a cylindrical block means located in said second tubular means and having an outside diameter approximately equal to or slightly less than the inside diameter of said second tubular means so as to be slidably telescopically receivable therewithin,
a transverse radially extending annular abutment surface on said cylindrical block means forming an annular joint with said second tubular means and facing said plate means and said sealing means and being axially spaced therefrom,
a slidable annular ring means mounted adjacent said block means and having an outside diameter sufficiently less than the inside diameter of said second tubular means so as to be axially movable therein relative to said block means,
an annular recess in the outer periphery of said ring means defined by a transverse radially extending surface axially'spaced from and facing said block means and an axially extending annular surface radially inwardly spaced from and facing said second tubular means,
said annular recess defining an O-ring groove in conjunction with said block means and said second tubular means,
an O-ring sealing member of larger cross-section than I said ring means having a spring seat aligned with and receiving the adjacent end of said spring means. 7. The invention as defined in claim 6 and wherein:
said ring means having a central air cavity,
said block means having a central air cavity generally aligned with the central air cavity in said ring means, and I connecting passage means extending radially inwardly from said air passage means to said central air cavity in said ring means.
8. The invention as defined in claim 7 and having:
an annular air cavity between said sealing means and said ring means including an air cavity portion axially aligned with and located radially inwardly of a said skirt portion so that high pressure air in said air cavity portion is effective to exert a radially outwardly directed force on said skirt portion.
9. The invention as defined in claim 6 and wherein:
said second tubular means having a constant inside diameter,
said plate means and said sealing means and said ring said abutment means and said block means holding said plate means and said sealing means and said ring means and said spring means n operative as-- sembled position. I 10. The invention as defined in claim 9 wherein said first and second tubular means comprise one continuous piece of tubular material.