WO1995020117A1

WO1995020117A1 - Pressure actuated drain valve

Info

Publication number: WO1995020117A1
Application number: PCT/US1994/000960
Authority: WO
Inventors: Donald Dekle Bartholomew
Original assignee: Proprietary Technology, Inc.
Priority date: 1994-01-24
Filing date: 1994-01-24
Publication date: 1995-07-27
Also published as: AU6825794A

Abstract

The present invention valve (10) is operable to drain fluid remaining in a conduit system. This drain valve (10) is of a general type known as a biased open line condition change responsive check valve. The present invention drain valve (10) is comprised of a conduit (30), a spring (32), a fluid blockage device (38) and a seal (36). The fluid blockage device (38) is movably suspended in an axial direction within a pocket (50) of the conduit (30) by the spring (32). The seal (36) is juxtapositioned around the fluid blockage device (38) and is movable therewith. Accordingly, the fluid blockage device (38) acts to axially compress the spring (32) when a predetermined axial fluid pressure differential occurs between the ends thereof such that the seal (36) and the fluid blockage device (38) act to prevent passage of the fluid through the adjacent conduit (30). However, when the fluid blockage device (38) is in its normally opened position, the fluid blockage device (38) and the seal (36) thereon allow remaining fluid to pass through the adjacent conduit (30). The present invention drain valve (10) also comprises a wire retainer (40) which has a substantially straight center segment (140) with angled segments (142 and 144) joined at each end thereof. The retainer (40) further has substantially semi-circular circumferential segments (146 and 148) extending from the respective ends (150 and 152) of each of the angled segments (142 and 144) opposite from the center segment (140).

Description

PRESSURE ACTUATED DRAIN VALVE

BACKGROUND OF THE INVENTION

This invention relates generally to a valve and specifically to a pressure actuated drain valve which is in a biased open position.

A common difficulty encountered within traditional sprinkler systems is that the sprinkler head mechanisms and the water supply hoses can be damaged due to repeated freezing and thawing of any water that remains withjn the system. Such conventional non-draining in-ground sprinklers are generally shown in the following U.S. Patents, all of which are entitled "Pop-Up Sprinkler": 4,616,780 which issued to Abbott on October 14, 1986; 4,448,353 which issued to Livne on May 15, 1984; and, 4,353,506 which issued to Hayes on October 12, 1982. All of these patents are incorporated by reference herewithin. Furthermore, the draining of moisture and excess fluid within a pressurized pneumatic conduit system is also a common problem. These pneumatic conduit systems are used to power a variety of tools and machinery. Any moisture build-up within such a pneumatic system can rust many of the tools and devices attached thereto. Accordingly, manually or automatically actuated drain valves are often attached to these pneumatic systems. Examples of such drain valves are disclosed in U.S. Patent 3,817,267 entitled "Valve Device for Draining Liquid Contaminant Collected from Compressed Gas" which issued to Hicks et al. on June 18, 1974, and U.S. Patent 2,819,799 entitled "Low Pressure Drain Valve" which issued to Wilkerson on January 14, 1958, both of which are incorporated by reference herewithin.

Conventional pressure actuated drain valves are typically expensive to manufacture. Many of these valves are either injection molded from a polymeric material or are machined from castings or metal stock. The tooling required to produce the plastic valves are traditionally very expensive and these plastic parts often crack or leak during exposure to freezing conditions. Furthermore, the durability of a threaded attachment portion of a plastic valve is also subject to cracking and cold flow due to the fairly low hoop strength of many low cost polymeric materials. Therefore, metallic valves are more desirable from a durability standpoint, however, the time consuming and capital intensive machining processes used make these valves economically infeasible for many high volume and low cost applications. Moreover, many valves require internal retainers for adequately securing the valve components within the valve body. Many conventional retainers are mounted within a well-defined radial groove that is formed within an interior surface of the valve body. Such a retention system is disclosed in U.S. Patent 4,979,721 entitled "Check Valve Having Combined Quick Disconnect Wrench Flat Defining Ridge" which issued to Gilbert on December 25, 1990 and is incorporated by reference herewithin. Another mounting method is to place a substantially flat disk-like retainer between a pair of mating housings. Both of these constructions typically require costly machining operations or extra parts. Therefore, it is desirable to have an environmentally durable pressure actuated drain valve which can be made in a relatively low cost manufacturing process.

SUMMARY OF THE INVENTION

In accordance with the present invention, a preferred embodiment of a new and useful valve is operable to drain fluid remaining in a conduit system. This drain valve is of a general type known as a biased open line condition change responsive check valve. The present invention drain valve is comprised of a conduit, a spring, a fluid blockage device and a seal. The fluid blockage device is movably suspended in an axial direction within a pocket of the conduit by the spring. The seal is juxtapositioned around the fluid blockage device and is movable therewith. Accordingly, the fluid blockage device acts to axially compress the spring when a predetermined axial fluid pressure differential occurs between the ends thereof such that the seal and the fluid blockage device act to prevent passage of the fluid through the adjacent conduit. However, when the fluid blockage device is in its normally opened position due to the fluid pressure force on the moving seal being reduced below the force applied to the moving seal by the spring, the fluid blockage device and the seal thereon allow remaining fluid to pass through the adjacent conduit.

Another aspect of the present invention drain valve comprises a wire retainer which has a substantially straight center segment with an angled segment joined at each end thereof. The retainer further has a substantially semi-circular circumferential segment extending from an end of each of the angled segments opposite from the center segment. The circumferential segments of the retainer are compressibly juxtapositioned within the interior surface of the normally corrugated wall sections of the conduit. The purpose of this retainer is to prevent loss of the movable seal and carrier.

An advantage of the present invention drain valve is that the fluid blockage device can be produced from a low cost material and in a low cost process. The fluid blockage device is stamped from a common metallic sheet of material. Another advantage of the present invention is that the valve components are environmentally durable. Moreover, the conduit of the present invention does not require extra processing steps in order to secure the retainer.

Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the preferred embodiment of a pressure actuated drain valve of the present invention in association with an in- ground sprinkler system;

FIG. 2 is an exploded perspective view of an alternate embodiment of the present invention pressure actuated drain valve of FIG. 1 ;

FIG. 3 is a sectional view of the alternate embodiment of the assembled present invention pressure actuated drain valve, taken along line 3-3 of FIG. 2; FIG. 4 is an end elevational view of a retainer used within the alternate embodiment of the present invention pressure actuated drain valve of FIGS. 1-3; and

FIG. 5 is a view similar to FIG. 3 of the preferred embodiment of the present invention pressure actuated drain valve of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 , the preferred embodiment of a pressure actuated drain valve 10 can be used to drain remnant fluid from an in-ground sprinkler system 12 or a compressed air conduit system (not shown). Valve 10 is of a general type known as a biased open line condition change responsive check valve. Sprinkler system 12 has a retractable sprinkler head 14, a protective skirt 16, a hollow shaft 18, a water supply tube 20 and a drain outlet 22. Valve 10 has a valve body or conduit 30 with a threaded portion which attaches to drain outlet 22 of sprinkler system 12. As is best illustrated in FIG. 5, valve 10 is comprised of conduit 30, a spring 32, a bushing 34, a seal 36, a fluid blockage device 38 and a retainer 40.

Conduit 30 is a hollow tubular member having an exterior surface 42 and an interior surface 44 with a bore 45 extending therethrough. Furthermore, conduit 30 has a pair of corrugated wall sections 46 and 48 separated by a pocket 50. Interior surface 44 contains threads 52 at an upstream attachment end 54 thereof. Alternately, exterior surface 42 of conduit 30 may be threaded at upstream end 54. Oppositely, a downstream end 56 is open and unobstructed. Moreover, pocket 50 is defined by a waist portion 60, an offset portion 61 and a constricted portion 62. Constricted portion 62 has a relatively smaller diameter than does waist portion 60. Conduit 30 is preferably made from a rust resistant metallic material such as galvanized steel or stainless steel. In an alternate embodiment, conduit 30 may also have an exterior gripping portion (not shown) with flats therearound for engagement by a wrench. Compression spring 32 is comprised of a plurality of helically wound coils. Spring 32 is concentrically mounted within constricted portion 62 of pocket 50 and is operable to movably bias fluid blockage device 38 centrally therein. Spring 32 is made from a rust resistant material such as a galvanized spring steel wire.

Fluid blockage device 38 is comprised of a cup 70 having a cylindrically shaped circumferential wall 72 which is substantially concentric within constricted portion 62 of pocket 50. Circumferential wall 72 of cup 70 also has a nominal diametral section 74 and a relatively larger diametral section 76 upstream therefrom, both of which are joined by an offset section 77. A flange 78 radially extends outward from enlarged section 76 at a first end 80. In the preferred embodiment, second end 82 may have a bottom portion inwardly extending in a substantially normal direction from circumferential wall 72 such that second end 82 is substantially enclosed and a basin 90 is not required. Cup 70 is preferably stamped from a sheet of metallic material such as galvanized steel. Therefore, this part can be manufactured in a series of low cost progressive forming dies.

In an alternate embodiment illustrated in FIGS. 2 and 3, cup 70 is substantially open and unobstructed at a second end 82 which is axially opposite and downstream from flange 78. In this embodiment, fluid blockage device 38 is further comprised of basin 90. Basin 90 similarly has a cylindrically-shaped outer wall 92 which is substantially concentric with circumferential wall 72 of cup 70. A flange 94 radially extends outward from outer wall 92 at a first end 96 thereof. Outer wall 92 also has a second end 98 from which inwardly extends an enclosed bottom surface 100. Basin 90 is stamped from a metallic sheet of material such as galvanized steel within a series of low cost progressive forming dies. Valve 10 is constructed so that cup 70 is movably suspended in an axial direction, denoted by arrow 102, within pocket 50 of conduit 30 by spring 32. Basin 90 snugly fits within nominal section 74 of cup 70 such that flange 94 of basin 90 is proximate with flange 78 of cup 70. Referring again to the preferred embodiment shown in FIG. 5, bushing 34 is located adjacent to offset section 77 of cup 70. Bushing 34 has an annular shape with a first face 122 and a second face 124. Moreover, bushing 34 has an inside edge 126 (see FIG. 2) which defines a passage 128 (see FIG. 2) centrally therethrough. Oppositely, bushing 34 has an outside edge 130 (see FIG. 2) formed around the perimeter thereof. Outside edge 130 of bushing 34 has a diameter which clears inside surface 51 of pocket 50. Bushing 34 is positioned such that first face 122 has a coil 132 of spring 32 compressibly abutting thereagainst. Second face 124 of bushing 34 also serves to substantially trap an O-ring type elastomeric seal 36 between flange 78 of cup 70 and itself.

Retainer 40 is juxtapositioned within inside surface 44 of conduit 30 so as to prevent fluid blockage device 38 from travelling in an upstream direction beyond the normally open position, shown in FIG. 3. Retainer 40 is a galvanized spring steel wire having a substantially straight center segment 140 with a pair of angled segments 142 and 144 joined at each end thereof. A pair of substantially semi-circular circumferential segments 146 and 148 each extend from ends 150 and 152 of each respective angled segment 142 and 144. Semi-circular segments 146 and 148 may have various circumferential lengths. For example, semi-circular segments 146 and 148 may each form overlapping fully circular rings or, alternately, may each only extend a few degrees around an imaginary circular line. Valve 10 is biased in a normally open position. This allows any remaining fluid such as water or a gas to flow through conduit 30 between cup 70 and pocket 50. This draining action can be further enhanced by angling valve 10 in a slightly downward direction between upstream end 54 and downstream end 56. When a predetermined axial fluid pressure differential occurs across a blocking segment, such as bottom 98 of basin 90, fluid blockage device 38 acts to axially compress spring 32 in axial fluid flow direction 102. Accordingly, seal 36 acts to prevent passage of fluid through conduit 30 by being compressed against offset portion 61 of pocket 50. In turn, when the fluid pressure significantly drops, spring 32 will axially bias fluid blockage device 38 to its normally open position.

While various embodiments of a pressure actuated drain valve have been disclosed, it will be appreciated that various further modifications may be made without departing from the present invention. For example, a variety of biasing means can be used in place of the disclosed compression spring. Moreover, a plurality of differently shaped seals and bushings may be employed. Various materials have been disclosed in an exemplary fashion, however, a variety of other materials may of course be employed. For instance, the disclosed conduit can be made from an elastomeric material. The fluid blockage device and retainer may also be made from an engineering grade polymeric resin such as nylon or acetyl. It is intended by the following claims to cover these and any other departures from the disclosed embodiments which fall within the true spirit of this invention.

Claims

The invention claimed is:

1. A valve for draining fluid comprising: a conduit having an exterior surface and an interior surface thereof within which fluid can flow therethrough, said conduit further having a pocket therein with an inside surface thereof, said pocket also having a constricted portion therein; a means for biasing being located within said pocket of said conduit such that said biasing means is axially compressible therein; a fluid blockage device having a peripheral wall with a blocking segment normal thereto for substantially enclosing a portion thereof, said peripheral wall further having a flanged segment radially extending outward therefrom at an end of said fluid blockage device opposite from said blocking segment thereof, said fluid blockage device being movably suspended in an axial direction substantially within said pocket of said conduit by said biasing means and being movably suspended in a normally open position relative to said constricted portion of said pocket; a seal being juxtapositioned around said fluid blockage device proximate to said flange thereof such that said seal is axially movable to a position adjacent to said constricted portion of said pocket for sealing thereagainst; and said fluid blockage device acting to axially compress said biasing means when a predetermined axial fluid pressure differential occurs between said ends thereof, said seal further acting to prevent passage of said fluid through said conduit when said fluid blockage device substantially compresses said biasing means, said fluid blockage device and said seal thereon allowing said fluid to pass through said conduit and around said fluid blockage device when said fluid blockage device is in its normally open position.

2. The valve of Claim 1 wherein: said fluid blockage device further comprises a cup having a cylindrically-shaped circumferential wall therearound with a flange radially extending outward from a first end thereof, said cup is suspended upon said biasing means and has said seal located externally therearound.

3. The valve of Claim 2 wherein: said fluid blockage device further comprises a basin snugly fitting within said cup, said basin has a cylindrically-shaped outer wall therearound with a flange radially extending outward from a first end thereof, said outer wall of said basin also has an enclosed bottom surface inwardly extending from a second end thereof, said flange of said basin is proximate with said flange of said cup.

4. The valve of Claim 3 wherein: said biasing means further comprises a spring having helical coils thereof which substantially wrap around said circumferential wall of said cup.

5. The valve of Claim 4 further comprising: a bushing having an annular shape with a first face and a second face thereof, said bushing being mounted around a predetermined portion of said circumferential wall of said cup and having at least one of said coils of said spring abutting thereagainst on said first face thereof; and said second face of said bushing and said flange of said cup axially trapping said seal- therebetween.

6. The valve of Claim 3 wherein: said cup is substantially open at said second end thereof.

7. The valve of Claim 3 wherein: said cup and said basin are stamped from a sheet of metallic material.

8. The valve of Claim 2 wherein: said second end of said cup has a bottom portion inwardly extending in a substantially normal direction from said circumferential wall thereof such that said second end of said cup is substantially enclosed.

9. The valve of Claim 1 wherein: said fluid is further defined as being water.

10. The valve of Claim 9 further comprising: a lawn sprinkler system having said conduit attached thereto whereby said valve drains said water therefrom when said water pressure is substantially reduced thereby preventing harmful freezing of said water therein.

11. The valve of Claim 1 further comprising: a retainer being mounted within said interior surface of said conduit for inhibiting said fluid blockage device from axially traveling beyond said normally open position in a direction opposite from said closed position.

12. The valve of Claim 11 wherein: said retainer is defined as a wire having a substantially straight center segment with an angled segment being joined to each end thereof, said retainer further has a pair of substantially semi-circular circumferential segments each extending from a respective end of each of said angled segments opposite from said center segment, said pair of substantially semi-circular segments are compressibly juxtapositioned within a preselected portion of said interior surface of said conduit.

13. The valve of Claim 1 wherein: said conduit has an attaching end thereof being threaded therearound.

14. The valve of Claim 1 wherein: said fluid is further defined as a gaseous medium.

15. A valve for draining fluid comprising: a conduit having an exterior surface and an interior surface thereof within which fluid can flow therethrough, said conduit further having a pocket therein with an inside surface thereof; a means for biasing being located within said pocket of said conduit such that said biasing means is axially compressible therein; a fluid blockage device being stamped from at least one metallic sheet forming a peripheral wall thereof and forming a blocking segment which substantially encloses an end thereof, said stamped peripheral wall forming a flanged segment which radially extends outward therefrom at an end of said fluid blockage device opposite from said blocking segment thereof, said fluid blockage device being movably suspended in an axial direction substantially within said pocket of said conduit by said biasing means and being movably suspended in a normally open position relative to said pocket of said conduit; a seal being juxtapositioned around said fluid blockage device proximate to said flange thereof such that said seal is axially movable to a position adjacent to a predetermined portion of said pocket of said conduit for sealing thereagainst; and said fluid blockage device axially compressing said biasing means when a predetermined axial fluid pressure differential occurs between said ends thereof, said seal further preventing passage of said fluid through said conduit when said fluid blockage device substantially compresses said biasing means, said fluid blockage device and said seal thereon allowing said fluid to pass through said conduit when said fluid blockage device is in its normally open position.

16. The valve of Claim 15 wherein: said fluid blockage device further comprises a cup being stamped from a metallic sheet which forms a cylindrically-shaped circumferential wall therearound with a flange radially extending outward from a first end thereof, said cup is suspended upon said biasing means and has said seal located externally therearound.

17. The valve of Claim 16 wherein: said fluid blockage device further comprises a basin snugly fitting within said cup, said basin is stamped from a metallic sheet forming a cylindrically-shaped outer wall therearound and forming a flange radially extending outward from a first end thereof, said outer wall of said basin also has an enclosed bottom surface formed therein which inwardly extends from a second end thereof, said flange of said basin is proximate with said flange of said cup.

18. The valve of Claim 17 wherein: said biasing means further comprises a spring having helical coils thereof which substantially wrap around said circumferential wall of said cup.

19. The valve of Claim 18 further comprising: a bushing having an annular shape with a first face and a second face thereof, said bushing being mounted around a predetermined portion of said circumferential wall of said cup and having at least one of said coils of said spring abutting thereagainst on said first face thereof; and said second face of said bushing and said flange of said cup axially trapping said seal therebetween.

20. The valve of Claim 15 further comprising: a lawn sprinkler system having said conduit attached thereto whereby said valve drains water therefrom when water pressure is substantially reduced thereby preventing harmful freezing of water therein.

21. The valve of Claim 15 further comprising: a pneumatic system having said conduit attached thereto whereby said valve drains a gas therefrom when said gas pressure is substantially reduced.

22. A retainer juxtapositioned within a tubular conduit for maintaining the preselected position of components of a valve contained therein, said retainer comprising: a wire having a substantially straight center segment with an angled segment being joined to each end thereof, said retainer further having a pair of substantially semi-circular circumferential segments each extending from a respective end of each of said angled segments opposite from said center segment, said pair of substantially semi-circular segments being compressibly juxtapositioned within a preselected portion of an interior surface of said tubular conduit.

23. The retainer of Claim 22 further comprising: a lawn sprinkler system having said tubular conduit attached thereto whereby said valve drains water therefrom when said water pressure is substantially reduced thereby preventing harmful freezing of said water therein.