GB2289754A - Pressure reduction valve - Google Patents

Abstract

A pressure reduction valve assembly for filling balloons with gas from a bottle of pressurized gas comprises a body (11) formed from a blank by a forging or stamping process with an integral protruding housing (12) for receiving the components of a pressure relief valve (13). The body (11) also includes a union (18) for connection to the gas bottle, an outlet structure (17), and pressure regulation means (15) for reducing the pressure of gas supplied through the body (11) from the bottle to the outlet structure (17). <IMAGE>

Description

PRESSURE REDUCTION VALVE The present invention relates to a pressure reduction valve for fitting to a bottle of pressured gas, and arranged for filling balloons with gas from the bottle.

In a conventional pressure reduction valve for filling balloons from a bottle of pressured gas the valve body is turned from a brass blank which is then drilled and tapped to accept an inlet union for connection to the gas bottle, an outlet valve structure, and a pressure relief valve structure, together with a pressure regulating mechanism. Turning a valve body from a brass blank is wasteful of material, and requires at least the pressure relief valve, and the outlet valve structures to be provided with relatively small diameter, externally screw-threaded spigots which are received in correspondingly internally threaded bores formed in the body in order to secure the valve structures to the body. The relatively small diameter spigots define a potential fracture point should the valve be subject to unsympathetic handling.

In accordance with the present invention, there is provided a pressure reduction valve for filling balloons with gas from a bottle containing such gas under pressure, the pressure reduction valve including a body formed from an appropriate blank by a forging or stamping operation, and integrally including an externally protruding housing for receiving components of a pressure relief valve, the body having a union for coupling to a bottle of pressurized gas, an outlet structure, and pressure regulation means for reducing the pressure of gas supplied in use through the valve from the bottle to the outlet structure.

Preferably said housing has at least one vent passage in the wall thereof adjacent the main part of the body and directed so as to be downward when the gas bottle to which the valve assembly is applied is upright.

Preferably the body includes an integral, outwardly protruding, externally screw-threaded union with which a correspondingly internally screwthreaded fitting of the outlet structure is engaged.

Conveniently the pressure relief valve structure and the outlet structure extend from the body in opposite directions, the two structures having a common axis intersecting the axis of the bottle coupling union at right angles.

Conveniently the pressure regulating means has its operative axis co-extensive with the axis of the bottle coupling union.

Preferably the exterior of the outlet structure is plain, and locking means is provided to resist relative movement of the screw-threaded connection of the outlet structure to the body.

Desirably the locking means is an adhesive.

Preferably the body includes an integral, internally screw-threaded region receiving the bottle coupling union as a screw fit therein. Desirably the bottle coupling union and the associated region of the body are plain and a locking means, desirably in the form of an adhesive, is supplied to the screw-threaded interconnection to resist removal of the union from the body.

Preferably the pressure regulating means is received partially within the body, and partially within a housing component rigidly attached to the body, the pressure regulating means being incapable of adjustment after the housing has been secured to the body.

Preferably the pressure relief valve is adjustable in order to adjust the pressure at which the pressure relief valve opens, the assembly further comprising locking means for restricting adjustment of the pressure relief valve. The pressure relief valve conveniently includes an adjustment member in screw-threaded engagement with the housing, the locking means comprising an adhesive for restricting relative rotational movement of the adjustment member with respect to the housing.

The locking means may further comprise a cover restricting access to the pressure relief valve in order to resist adjustment thereof.

One example of the invention is illustrated in the accompanying drawings, wherein: Figure 1 is a cross-sectional view of a pressure reduction valve equipped with an outlet valve structure adapted for use with foil balloons, and Figure 2 is a cross-sectional view illustrating an alternative outlet valve structure for use with latex balloons.

Referring first to Figure 1 the balloon filling pressure reducing valve comprises a body 11 formed as a stamping, or forging, from leaded brass and includes a central region from which project first, second, third, and fourth circular cylindrical regions, the axes of the four regions lying in a common plane, and the axes of the first and third regions being aligned and intersecting the aligned axes of the second and fourth regions at right angles.

The first circular cylindrical region projecting outwardly from the central region of the body 11 defines a housing 12 for a pressure relief valve structure 13. The second region 14 receives part of a pressure regulating mechanism 15 and the third region 16, opposite the first region 12, is externally screw-threaded to receive an outlet valve structure 17. The fourth region 18 is internally screw-threaded and receives a bottle coupling union 19.

After being formed as a hot forging or a stamping from a plain cylindrical leaded brass blank the body 11 is drilled and tapped as necessary to provide internal passages and threaded regions, and before assembly of the various components the body is thoroughly cleaned to ensure that all swarf and oil has been removed.

The bottle coupling union 19 is generally of conventional form and includes an elongate tube received at one end as a screw fit in the fourth region 18 of the body 11. Within the body the bore of the region 18 includes a frusto-conical seating 21 against which a rounded end region of the coupling 19 bears to ensure a seal between the coupling 19 and the body 11. At its opposite end the tube of the coupling 19 has a rubber sealing ring 22 and captive on the exterior of the coupling 19 is a manually rotatable screw-threaded clamping ring 23 for clamping the union 19 in sealing engagement with a corresponding outlet on a gas bottle in known manner.

A drilling 24 constituting a continuation of the passage within the region 18 terminates at a valve seat 26 opening into a transverse passage 25 of the body 11. The central stem 27 of the pressure regulating mechanism 15 extends across the passage 25 and has a sealing insert at its lower end engagable with the seat 26 to close the drilling 24 from the passage 25.

The stem 27 carries an integral piston 28 at its end remote from the valve seat 26, the piston 28 being in sliding, sealing relationship with the inner cylindrical surface of a turned brass housing 29. The housing 29 is anchored to the second region 14 by being in left-hand, screw-threaded relationship therewith, and being locked against rotation once fitted thereto, by a transverse rivet 31 and a thread locking adhesive. The space within the housing 29 beneath the piston 28 is vented to atmosphere through an aperture 32 into the wall of the housing 29 and a helical compression spring 33 acts between the bottom of the piston 28 and the body 11 to urge the piston 28 and stem 27 upwardly away from the valve seat 26.

The stem 27 is hollow, and its passage extends through the piston 28 so as to communicate with the housing 29 above the piston 28. At its lower end the passage of the stem 27 communicates, by way of a crossdrilling with the passage 25.

When the union 19 is connected to a gas bottle then gas under pressure enters the passage 25 through the drilling 24 (assuming that the sealing face of the stem 27 is spaced upwardly from the valve seat 26) and the pressure conditions in the passage 25 are communicated through the cross drilling and the passage of the stem 27 to the space in the housing 29 above the piston 28 so as to drive the piston and stem downwardly against the action of the spring 33 thus closing the sealing insert at the lower end of the stem 27 onto the valve seat 26. In this position of the stem 27 the passage 25 is disconnected from the pressure conditions in the bottle.

At one end the passage 25 communicates with the interior of the pressure relief valve housing 12 through a valve seat 35 integral with the body 11. A valve member 36 slidable axially within the housing 12 is urged with a compression spring 37 into engagement with the seat 35.

A screw-threaded spring abutment member 38 is engaged with an internally threaded end region of the housing 12 remote from the seat 35 and provides an adjustable abutment against which the spring 37 acts.

The axial position of the closure member 38 determines the loading applied by the spring 37 to the valve member 36, and thus the pressure at which the valve member 36 will be moved away from the seat 35 against the action of the spring 37. The member 38 has a central passage of hexagonal cross-section to receive an Allen-key for adjustment and after adjustment the member is locked in position by use of a thread locking adhesive. A blanking cap 38a is screwed into the open end of the housing 12 and locked in place by adhesive. Closely adjacent the central region of the body 11 the lithe housing 12 is formed with three vent passages 39 through which pressure in the passage 25 will be vented to atmosphere when the valve member 36 is lifted away from the seat 35.

The disposition of the passage 39 is such that in normal use of the balloon filling valve, when the associated gas bottle is upright, should venting of the passage 25 occur then the issue of pressurized gas will be downwardly, away from a user, on the opposite side of the body 11 to the normal outlet valve 17, and closely adjacent the body 11, so as to minimise the hazard to the operator.

The opposite end of the passage 25 from the pressure relief valve structure 30 opens into the bore of the externally screw-threaded third region 16 of the body 11. The region 16 is received as a screw fit within an elongate cylindrical tube 41 forming the body of the outlet valve structure. The outlet valve structure is generally of conventional form and includes a valve element 42 movable within the tube 41 and having a peripheral flange which can cooperate with a resilient sealing ring 44 supported by an internal flange 43 of the tube 41. A helical compression spring 45 acts at one end against the body 11 and at its opposite end against the valve element 42 and urges the valve element 42 to a position in which its flange abuts the sealing ring 44 and so prevents flow of gas from the passage 25 through the tube 41.The outer end of the element 42 carries a nozzle assembly 46 adapted for use in cooperation with foil balloons, the nozzle assembly 46 being depressible towards the body 11 against the action of the spring 45 to lift the flange of the element 42 away from the sealing ring 44 and thus permit gas under pressure to flow from the passage 25 between the element 42 and the sealing ring 44 and through the nozzle assembly 46 into a balloon.

It will be recognised that when the outlet valve structure 17 is opened the pressure in the passage 25 will fall, with a corresponding fall in the pressure acting on the upper face of the piston 28. Thus the spring 33 will be able to move the piston 28 and thus the stem 27 upwardly reestablishing the gas flow communication between the drilling 24 and the passage 25. The pressure which can be achieved in the passage 25 is of course determined by the balance between the pressure acting on the piston 28 in one direction and the spring 33 acting on the piston 28 in the opposite direction and thus a pressure regulating effect is achieved ensuring that the pressure in the passage 25 does not exceed a predetermined safe balloon inflating pressure, irrespective of the amount by which the pressure in the bottle exceeds the predetermined pressure.

It will be understood that the pressure maintained in the passage 25 is dependent upon the rate of the spring 33, thus during assembly a suitable rate spring is selected depending upon the intended use of the pressure reduction valve. Once an appropriate rate spring has been selected and the housing 29 secured in position it will be understood that adjustment of the pressure regulating valve is effectively prevented since no access can readily be obtained to substitute an alternative spring 33 or to introduce shims or the like to vary the spring rate.

During normal operation of the regulating mechanism 15 the pressure in the passage 25 will not achieve a value at which the valve member 36 is lifted from the valve seat 35. However, if, for any reason, the regulating mechanism should fail then the pressure in the passage 25 may exceed what is deemed to be a safe pressure, at which point the valve member 36 is lifted from the seat by the pressure and pressurized gas is vented to atmosphere through the vent passage 39.

The housing 12, as an integral part of the forged or stamped body 11, is particularly robust, and the closure member 38 has no flats or other shaping to facilitate its removal. Similarly, the housing 29 is locked to the body 11 and has no shaping to facilitate its removal. In the case of the outlet valve assembly 17 it is mounted on the relatively large diameter third region integral with the body 11 and so is particularly robust. The outer surface of the tube 41 is a plain cylindrical surface, again without flats or other shaping to facilitate removal. Similarly, there is no shaping on the coupling 19 which will facilitate its removal, and all of the screw-threaded components are held against release, having been screwed into their predetermined positions, by means of a thread adhesive such as LOCTITE 270.Thus there is no facility for adjustment of the valve by the end user, and it would be virtually impossible for the end user to remove any of the components to obtain access to the interior of the valve. Any such attempt would involve obvious, and probably distinctive, damage to the valve components. In essence therefore the valve is tamper-proof.

The alternative outlet valve construction illustrated in Figure 2 is intended for use with latex balloons. Again there is an externally plain cylindrical tube 41 in screw-threaded engagement with the third region 16 of the body 11, the two being locked together after assembly as described above. The tube 41 has an internal peripheral shoulder 143 against which an integral flange 144 of a neoprene or similarly flexible nozzle member 146 abuts. The nozzle member 146 is not slidable relative to the tube 41, but is, by virtue of its flexibility, deflectable relative thereto laterally. The nozzle 146 has an internal gas flow passage housing a valve member 142 in the form of a solid metal rod having a flange at its innermost end. A helical compression spring 145 acts between the valve member 142 and the body 11 to urge the flange of the valve member against the sealing flange 144 of the nozzle 146.

Lateral deflection of the nozzle 146 carries the valve member 142 with it thus lifting part of the flange of the valve member away from the flange 144 of the nozzle and allowing gas to flow from the passage 25 through the hollow element 16, around the flange of the valve member 142 and along the internal passage of the nozzle 146 into a balloon the neck of which is engaged over the nozzle.

It will be recognised that other outlet structures could be utilized if desired including, for example, the use of an elongate hose with a remotely positioned valve, and the provision of a pressure gauge or the like.

Moreover materials other than brass and leaded brass may prove suitable.

Claims (15)

1. A pressure reduction valve assembly for filling balloons with gas from a bottle containing such gas under pressure, the pressure reduction valve assembly including a body formed from an appropriate blank by a forging or stamping operation, and integrally including an externally protruding housing for receiving components of a pressure relief valve, the body having a union for coupling to a bottle of pressurized gas, an outlet structure, and pressure regulation means for reducing the pressure of gas supplied in use through the valve from the bottle to the outlet structure.

2. A valve assembly as claimed in Claim 1, wherein said housing has at least one vent passage in the wall thereof adjacent the main part of the body and directed so as to be downward when the gas bottle to which the valve assembly is applied is upright.

3. A valve assembly as claimed in Claim 1 or Claim 2, wherein the body includes an integral, outwardly protruding, externally screwthreaded union with which a corresponding internally screw-threaded fitting of the outlet structure is engaged.

4. A valve assembly as claimed in Claim 3, wherein the exterior of the outlet structure is plain, further comprising locking means for resisting relative movement of the screw-threaded connection of the outlet structure to the body.

5. A valve assembly as claimed in Claim 4, wherein the locking means is an adhesive.

6. A valve assembly as claimed in any one of the preceding claims, wherein the pressure relief valve and the outlet structure extend from the body in opposite directions, and have a common axis intersecting the axis of the bottle coupling union at right angles.

7. A valve assembly as claimed in any one of the preceding claims, wherein the pressure regulation means has its operative axis co-extensive with the axis of the bottle coupling union.

8. A valve assembly as claimed in any one of the preceding claims, wherein the body includes an integral, internally screw-threaded region receiving the bottle coupling union as a screw fit therein.

9. A valve assembly as claimed in Claim 8, wherein the bottle coupling union and the associated region of the body are plain, and a second locking means is supplied to the screw-threaded interconnection to resist removal of the union from the body.

10. A valve assembly as claimed in Claim 9, wherein the second locking means is an adhesive.

11. A valve assembly as claimed in any one of the preceding claims, wherein the pressure regulating means is received partially within the body, and partially within a housing component rigidly attached to the body, the pressure regulating means being incapable of adjustment after the housing has been secured to the body.

12. A valve assembly as claimed in any one of the preceding claims, wherein the pressure relief valve is adjustable in order to adjust the pressure at which the pressure relief valve opens, and further comprising third locking means for resisting adjustment of the pressure relief valve.

13. A valve assembly as claimed in Claim 12, wherein the pressure relief valve includes an adjustment member in screw-threaded engagement with the housing, the third locking means comprising an adhesive.

14. A valve assembly as claimed in Claim 12 or Claim 13, wherein the third locking means comprises a cover restricting access to the pressure relief valve to resist adjustment thereof.

15. A pressure reduction valve assembly substantially as hereinbefore described with reference to any one of the accompanying drawings.