CA2179811A1

CA2179811A1 - Sheath valve

Info

Publication number: CA2179811A1
Application number: CA002179811A
Authority: CA
Inventors: Michael D. Handler
Original assignee: Individual
Current assignee: Reseal International LP
Priority date: 1994-10-24
Filing date: 1995-10-20
Publication date: 1996-05-02
Also published as: EP0746711A4; EP0746711A1; JPH09507564A; CN1137308A; KR100235276B1; WO1996012904A1; JP2859442B2; CN1045816C; US5613517A; TW389815B; AU3893995A; AU6063696A; AU693707B2

Abstract

A linear sheath valve (11) having a valve platform (33) and a conforming cover (21). The valve platform (33) can have inlet (39) and outlet (45) channels to carry liquid into and out of the valve. An elastomeric membrane (29) is held under tension between the cover (21) and the platform (33) so as to control the flow of liquid between channels. The cover (21) includes an expansion area on the cover surface (22) adjacent to the membrane (29) and between the inlet (39) and the outlet (45). Liquid can flow through the valve only when it is under sufficient pressure to press the membrane (29) into the expansion area, creating a flow path from the inlet (39) between the membrane (29) and the valve platform (33) to the outlet (45). Discontinuance of the pressure on the liquid allows the membrane (29) to seal the inlet (39) and outlet (45), thus preventing any flow between them.

Description

wo 96/12904 r~ 3lls 217981~
.
IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
PCT APPLICATION

SP~CIE~ICATION

TITLE: IINEAR MODE SHEATH VALVE

Field Of The Invention This invention relat~s to sheath valves, i.e., valves which permi~ the flow of liquid in only one direction. In particu!ar, it relates to a sheath valve which uses a tensioned linear sheath, rather than a cylindrical sheath.

~ack~round Of The InventiQn A sheath valve is a type of one-way valve which permits a liquid, gas, or other flowable material to be dispensed, but does not permit anything to pass b.,~h~.d~ through the Yalve, and so prevents possible ~nn~min~tinn to the contents remaining in the container.

~ WO9611t904 2179811 r~llu.,,~/13l18 One form of one-way valve is a cylindrical core l~nrQmr~ l by an elastic cylindri-c~l sheath, with the core having an entrance tube therein leading to a portion of the sheath, and an exit tube leading from the sheath. The two tubes are closed by the sheath and do not interconnect; but pressure applied to the liquid being dispensed serves to expand the sheath so that the liquid can pass from the entrance tube to the exit tube. Upon release of the pressure, the sheath contracts, sealing the valve against any possible reverse contamina-tion.
Various paterlts have issued directed to this cylindrical valve. Examples of these include Gerber U.S. Patent 4,846,810; Debush U.S. Patents 5,279,330; 5,305J83, zmd 0 5,305,786; and Pardes U.S. Patent 5,092,855. Each of these uses a cylindrical sheath surrounding a cylindrical Yalve core. This cylindrical structure is not only difficult and costly to ,. ~,.,r I ,c~ but also difficult and costly to assemble. A problern with a cylindrical sheath valve is that, to maintain tension, the inside diameter of the cylindrical sheath should be smaller in diameter than the outside diameter of the core, resulting in difficult assembly.
This preserlt invention is directed to a linear sheath structure which is simpler and cheaper to ".~....r,. ~ , but provides an effective one-way valve.
Brief Summarv Of Tne Invention My invention uses inexpensive flat, elastic sheath material held in tension over a 20 convex surface, that is, a surface which is wholly or partly curved or distended along at least one axis of a valve platform, which surface I refer to as a valve platform having a ~ WO96/12904 2~7~8~ r~ J~ 8 convex surface. There are entrance and exit channels and ports in the valve platform ~v~ f ~;~lg with the interface between the sheath and the valve platform. It is important that the sheath be in tension over this surface, in order to provide a tight, one-way seal for the channels. The valve can control flow of various types of flowable produas, such as 5 liquids, pastes, and gases, referred to herein as "liquids."
The various ~ Lod;..~ L~ include as elements (a) a valve platform with a convex surface; (b) a sheath which can b~ a flat elastic sheet prepared from roll stock, a preformed injection, or l_Ulll~ ;UI~ molded ~ o.l. 1 and (c) a housing ~u~uOl~ L or cov~r for sheath protection and retention, the cover and valve platform being s~aled together.
LO There are several key elemerlts to my invention:
First, is the surface of the valve platform that is the functional area in terms of barrier and closure, the sheath being in tension over the surface of the sheath where it interfaces with the valve platform. This platform can take a variety of shapes, ranging from ;I dome to one-half of an elongated cylinder. The key consideration is the natural lay and stretch of the sheath when placed in tension, and its tight contact and interface with the valve platform.
Second, is the number and ( (( ~ ot' entrance and exit ports and channels that function to channel liquid flow within the context of the valve.
Third, are the .. IIA~ for anchoring the sheath to the platform. These anchor 20 ((~ IC can take various forms, but each useS a cover piece which s~..lw;~ the edges of the sheath between the platform and the cover piece; and each provides for spacing between the cover piece and the platform in ~ e area where the ports i~terface with ~he .

wo 96112904 ~ 2 1 7 9 ~ ~ 1 PCr~s9~/l3~l8 sheath, i.e., an expansion chamber, so that the sheath can expand under pressure to permit fluid flow bet~een the poes.

wo 96112904

2 ~ 79~ ~
- Description Of The Drawin~s Fig~ I is a perspective view of a dispenser of the type which might use the linear sheath valve of this invention.
Fig. 2 is a section, taken on line 2-2 of Fig. 1, showing how the valve can be used in s a dispenser.
Fig. 3 is a perspective view, partially broken away, of the linear valve mountedwithin a spout, such as the spout of Fig. 2.
Fig. 4 is an explodet p~ ;v~ view of a linear sheath valve. This valve has a ~enerally rectangular shape. It shows the X- and Y-axes referred to below.
0 Fig 5 is a top plan view, partially broken away, of the valve of Fig. 4.
Fig. 6 is a section, taken on line 6-6 of Fig. 5, showing the inner construction of the valve.
Fig. 7 is a section, taken on line 7-7 of Fig. 5, showing further details of theconstruction.
Fig. 8 is similar to Fig. 6, showing a mrrlifir~tir~n of the linear valve.
Fig. 9 is a plan view, partially broken away, showing a mn~lifir1tirn of the valve in which at least the functional area of the valve platform is elliptical in shape.Fig. 10 is a section, taken on line 10-10 of Fig. 9, showing the inner construction of the valve.
Fig. 11 is a section, taken on line 11-11 of Fig. 9, showing further details of the cons~ruction.

~ WO 9G112904 2 1 7 9 8 1 ~ PCTIUS951l3ll8 Fig. 12 is similar to Fig. 10, but shows a mrf~ifir~rirn of th~ structure of Figs. 9, 10, and 11.
Fig. 13 is similar to Fig. 10, but shows a ..,~ ;r.~l of the structure of Figs. 9, 10, and 11.
s Fig. 14 is a perspeaive view of a further mrflifir7tirrl of the valYe, in which the funaional area of the valve platform is dome-shaped or partially spherical-shaped. It shows only the valve platform.
Fig. 15 is a seaion, taken on line 15-15 of Fig. 14, to which a cover and a sheath have been added, showing the inner ~ u~;oll of this modified valve.
0 Fig. 16 is similar tO Fig. 15, but shows a mr,rlifir~tirn of the valve of Fig. lS.
Fig. 17 is a top view of Fig. 14.
Fig. 18 is a modiScation of the struaure of Fig. 17, showing an oval-shaped periphery.
Fig. 19 is a mflrlifir~tif~n of the struaure of Fig. 17, showing another type ofg~nerally reailinear-shaped periphery with rounded corners.
Figs. 20, 21, 22, and 24 are similar to Fig. 15, showing n~flifir~tion~ of the struaure of Fig. 15.
Figs. 23 and 25 are end views of Figs. 22 and 24, ~ ly.
Detailed Description Of The Invention A typical installation 1 in which my linear sheath valve could be used is shown In Fig. 1. Collapsible container 3 ~ontains liquid to be dispensed, which is also the liquid the .

-I WO 96/12904 2 ~ n 1 ~ 8 ~ I PCTIUS95~13118 user wants to be sure not to i~ ell~ly . (~ P by back-flow from or through a dispenser. A dispenser nozzle s having a housing 7 and outlet 9 is mounted on the container 3.
A linear sheath valve 11, positioned and sealed by mounting ribs 13, is positioned 5 within housing 7 near the outlet 9 (Fig. 2). A pump, having a flexible, depressible ball 15, ~nd a flapper check valve 17, i~ .,ne.~ the container 3 with the housing 7 Pressure on . ball 15 closes valve 17 and, so, forces liquid whidh is within the housing 7 out through the sheath valve 11. Releas~ of pressure on ball 15 results in the ball resuming its normal round shape; and, in so doing, il draws liquid up .~rom container 3 ~inn~llr~tl~ r~tlcly~ the 0 sheath valve resumes the normal, sealed .. ~llrl~,.. iO.. The liquid can then be forced out through the sheath valve during the next cyde.
For reasons to be described below, it is important to note that the liquid which is being dispensed must be forced under pressure through sheath valve 11.
The sheath valve of this invention is a linear valve, that is, its sheath (Pl~ct~ml.ri~
5 membrane) is not cylindrical, but is made of material which is either sheet material or essentially planar. The parts of the linear sheath valve are seen in Figs. 4-7. They include:
A cover 21 having an inner conve surface æ, surface 22 having a peripheral cover shoulder 25 for sealing; a core or valve platform 33 with an inner convex surfaoe 34, ~"",~ Iy to concave surface 22, and a peripheral seat 35 to receive and mate with 20 cover shoulder 25; and a s~lh~r~nt~ y planar cl~ sheet membrane 29, which is ro~;~ionPd between concave surface 22 and convex surface 34, and is held in tension against ~WO 96/12904 21 7 g ~1 ~ r~ ll8 convex surface 34. Here, the interface of the two surfaces has a ....r;~,."f~ 7 which is a portion of a f~ylinder, i.e.~ arcuate.
Oile way to make the sheath valve illus~rated in Fig. 4 is as follows: An elastic ...Ll~.lc 29, larger in si2e than the valve platform or cover, is held in a planar format with t~nsion applied in at least the X-axis direction, as indicated in Fig. 4. The convex surface of valve platform 33, and the concave surfaoe of cover 21, are then posilioned in qlignment above and below Ill~,llI~Ialle 29. The pl~.tform and cover are pressed together, clamping m.~nnhpnP 29 (Pig. 6), and putting the ~I~u~r;.~c amount of tension into ...... 1.l~, ~ 29 as it is stretched across convex surfaoe 34.
o With the ~li.d~ion of llltt~coni~c membrane 29 is cut, and platform seat 35 is welded to cover shoulder 25 around the entire periphery, creating a hermetic seal.
In other ~mhof7im~ntc, as shown in Figs. 10,12, and 13, membrane 29 can be pre-cut or pre-formed, positl;oned, and clamped, with the tension on membrane 29 being ~pplied during the mating process of the valve platform and cover. Further, in these embodiments, the process of sealing the platform and cover together can be achieved with qdhesives, ..~ or other means.
Returning to Figs. ~7, inlet channel 39 in valve platforrn 33 has an irllet channel 39 with container end 43 and sheath end 41. This channel leads from a source of liquid to sheath end 41 which is closed by taut membrane 29. Valve platform 33 also has outlet channel 45 with sheath end 47 and outlet or user end 49. Sheath end 47 of this channel is closed by taut Ill~.llbl~ilC 29.

~vo 96~12904 21 7 9 81 ~ r~ l/U~,"/I3ll8 Surface 22 includes a recess or expansion chamber 23. Thus, though the peripheryof the elastomeric membrane is fitted tightly against convex surface 34, holding sheath ends 41 and 47 closed, the membrane can expand under liquid pressure into expansion area 23.
The liquid under pressure comes from inlet channel 39 and presses the membrane 29 into s the expansion area, and so provides a channel along conv surface 34, beneath membrane 29, between sheath end 41 of inlet channel 39 and sneath end 47 of outlet channel 45.
A~uld;~gly~ when liquid is foroed under pressure into inlet channel 39, it presses ~gainst the ~ dilC 29, pressing it into expansion chamber 23, and so creates ~ channel betwecn the membrane 29 and convex surface 34, running from inlet sheath end o 41 and outlet sheath end 47. As soon as the pressure on the liquid ceases, the membrane ~gain presses against channel ends 41 and 47, closing and sealing them. This means that the valve is closed, and nothing can pass backwards from outlet channel 45 to inlet channel 39.
The Yalve 11 is, then, a one-way valve, and . .,,,,~,,,,.,~..I~ cannot pass from the outside back into container 3, the source of the liquid being dispensed.
~5 As can be seen from the above, an effective on~way sheath valve has been made using a valve platforrn and a planar membrane, which is far easier to m7.1l1f~tllre than is one having a cylindrical core and a cylindrical sheath. This is so because, in order to maintain tension on the cylindrical unit, one must use a sheath having an inner diameter smaller than the outer diameter of the cylindrical core.
Fig. 8 shows a slight mo~lifi~ti~-n of my sheath valve. Here, the portions of the two inner surfaces 22 and 34 proximate to the expansion chamber 23, are flat, but the surfaces curve duwllwd.dly as they approach cover shoulder 25 and valve platform seat 35.

~ WO 9~/12904 2 ~ 7 9 8 1 1 r~ ..,Jl.?,l18 This produces an effective convex surface for the membrane, so that it is stretched taut, closing the inle~ and outlet channels.
Another mt)-~ifi~rinn is shown in Figs. 9, 10, and 11. Rather than have the two inner surfaces " L~a~ . in top view ~ rl~;u~.n;ol~ kuch as in Fig. 5), they are elliptical.
They function, however, in the same manner as the previously-described valves.
Figs. 10 and 11 show a modification of the clamp area (shoulder). As opposed to thc planar damp 37 shown in Figs. 6, 7, and 8, Fig. 10 shows a distinct point of prcssure, bead or ridge 27 in cover 21, with a matching ~ ,y recess 28 in the platform.
Pressing cover 21 against valve platform 33 serves to apply tension to membrane 29.
0 Fig. 12 shows another m()~ifi~rinn of clamp area 37. Here, the ". . l,~ ", is to have the surface 34 curve dowllwd~-lly as it d~ oo~ 7 platform seat 3~, while the cover clamp area has an angled, linear cross-section 38, creating a conical-like .~,llt;~,u,~;ol,.
Thus, the membrane is clamped by a point line of contact 40 around Ihe surface 34 of the VllVe platform. In this struaure, it is best to have greater friction between cover 21 and ~ 40 than between membrane 40 and platform 33. Alternatively, the membrane 29 can have a bead 30.
Fig. 13 is a further mt~ifi~ti~ n Here, the ~ <", ; membrane 29 has been molded to be a modified sheet. The membrane has a peripheral bead 30 which fits into rr~ , y recesses 36 in the cover 21 and the valve platform 33. This provides for an even tighter seal and wider range of assembly methods. The membrane is made taut, and held taut, however, by stretching over a convex v~lve platform surface 34, as the cover and ~ WO 96/12904 - 2 1 7 9 8 1 I PCT/US95113118 platform are pressed together, forcing the bc~d 30 into recesses 36. Fig. 16 is similar, exoept there the recess 36 is only in the valve platform.
- Another ~ aI1 ;S shown in Figs. 14 and 15. Here, the convex valve platformsurface 34 is dome-shaped (hemi-spherical shaped). A modification of this is also seen in Fig. 16.
Figs. 17, 1~, and 19 show mnrlifi(~tinnc to the peripheral shape of platform functional area 34. The cross-section of the sheath valve can include linear, domed, partially curved, and elliptical segments and ~u~r;gu~.~L;oll~ as ~ lu~ to providing ...... l.. A.. r tension and the anchoring . . IIA~
0 Figs. 20, 21, 22, and 24 show mn~lifil~otinnc to inlet channel 39 and outlet chanriel 45, including the positions of inlet 43 and outlet 49. The outlet can be solely in the cover 21, as an extension of chamber 23, if desired. As shown in Fig. 24, chanr;els can be In the form of a groove.
Fig. 22 shows how the outlet channel 45 can be an extension of expansion spaoe 23.
All of the above sheath valves operate in the manner as described above for Figs. 1 and 2. That is, liquid carried by a container will pass through the valve when relative pressure is applied to the liquid. This pressure causes the liquid entering through inlet channel 39 to press against the membrane 29 at the point of interface of channel and bl.-llC. This lifts the membrane (agunst the l~embrane tension~ into expansion area 23 ~ur~;ci~ ly such that the liquid flows between the m~mhr nl~ 29 and the valve platform 33 to the outlet channel 45. It then flows out that outlet channel. When the applied pressure on the liquid ceases, the tension on the membrane causes the membrane to again press 11 , .

~: `wo 96112904 2 1 7 9 8 ~ ~ PCTtUS95113118 tightly against the sheath ~nd 41 of the inlet channel 39 and the sheath end 47 of the outla channel 45, sealing them. Liquid can no longer flow in either direaion; and the container contents are sealed against any ~u~ ation entering the container through the valve.

Claims

I claim:

1. A linear sheath valve, said sheath valve including a valve platform, said valve platform having a convex surface, an inlet channel and an outlet channel in said valve platform, said channels leading to an inlet opening and an outlet opening, respectively, on said convex surface, said openings being spaced from one another, a cover for said convex surface of said valve platform, said cover having a concave surface complementary to said convex surface, said concave surface including an expansion chamber, and an elastomeric membrane positioned between said valve platform and said cover, tension means for holding said elastomeric membrane under tension with said elastomeric membrane taut against said convex surface and over said inlet opening and said outlet opening, whereby liquids can pass from said inlet channel to said outlet channel only when under sufficient pressure to overcome said tension on said elastomeric membrane and to cause said elastomeric membrane to move into said expansion chamber.

2. A linear sheath valve as set forth in claim 1 in which said valve platform and said cover are sealed to one another.

3. A linear sheath valve as set forth in claim 1 in which said convex surface and said concave surface have a line of common contact outside of said expansion chamber, and said elastomeric membrane is held between said surfaces along said line of contact.

4. A linear sheath valve as set forth in claim 3 in which said line of common contact provides said tension means.

5. A linear sheath valve as set forth in claim 1 in which at least one of said channels is a groove in at least one of said surfaces.

6. A linear sheath valve as set forth in claim 1 in which said elastomeric membrane has a peripheral bead, and said convex surface and/or said concave surface has a recess therein to receive said bead.

7. A linear sheath valve as set forth in claim 1 in which said elastomeric membrane has a peripheral bead therearound, whereby said tension means is caused by interaction of said bead with said convex surface and said concave surface.

8. A linear sheath valve as set forth in claim 1 in which one of said surfaces includes a peripheral ridge to receive said elastomeric membrane and the other of said surfaces includes a peripheral complementary recess to receive said elastomeric membrane.

9. A linear sheath valve as set forth in claim 1 in which said convex surface isarcuate.

10. A linear sheath valve as set forth in claim 1 in which said convex surface is substantially quasi-spherical.

11. A linear sheath valve as set forth in claim 1 in which said convex surface is substantially elliptical.

12. A linear sheath valve, said sheath valve including a valve platform having a platform inner surface, said valve platform including at least one channel for liquid, said channel leading through said platform to said platform inner surface, a cover for said valve platform, said cover having a cover inner surface facing said platform inner surface, and a linear elastomeric membrane mounted between said platform inner surface and said cover inner surface, tension means for holding said elastomeric membrane taut against said platform inner surface.

13. A linear sheath valve as set forth in claim 12 in which said valve platform and said cover are hermetically secured together.

14. A linear sheath valve as set forth in claim 12 in which said cover inner surface includes an expansion chamber.

15. A linear sheath valve as set forth in claim 14 in which said expansion chamber includes an outlet channel.

16. A linear sheath valve as set forth in claim 12 including at least two said channels.

17. A linear sheath valve as set forth in claim 12 in which at least one of saidchannels is positioned to running abutting said elastomeric membrane.

18. A linear sheath valve as set forth in claim 12 in which said elastomeric membrane has a peripheral bead therearound, and at least one of said surfaces includes recess to receive said bead.

19. A linear sheath valve as set forth in claim 18 in which said peripheral bead is at least part of said tension means.

20. A linear sheath valve as set forth in claim 12 in which one of said surfacesincludes a peripheral ridge to receive said elastomeric membrane and the other of said surfaces includes a peripheral complementary recess to receive said elastomeric membrane.

21. A linear sheath valve as set forth in claim 12 in which said platform inner surface is a convex surface and said cover inner surface is a concave surface.

22. A linear sheath valve as set forth in claim 21 in which said convex surface and said concave surface have a common line of contact, and said elastomeric membrane is held between said surfaces along said line of contact.

23. A linear sheath valve as set forth in claim 22 in which said common line of contact provides said tension means.

24. A linear sheath valve as set forth in claim 12 in which said platform inner surface includes a convex area running peripherally thereof and said cover inner surface includes a conical surface positioned to abut against said convex area and to thereby seal said elastomeric membrane between said convex area and said conical surface.

25. A linear sheath valve as set forth in claim 12 in which said convex surface is arcuate.

26. A linear sheath valve as set forth in claim 12 in which said convex surface is substantially quasi-spherical.

27. A linear sheath valve as set forth in claim 12 in which said convex surface is substantially elliptical.