GB2512228A

GB2512228A - Snapshut valve

Info

Publication number: GB2512228A
Application number: GB1411067.0A
Authority: GB
Inventors: David Guy Woodman
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-06-20
Filing date: 2014-06-20
Publication date: 2014-09-24
Also published as: GB201411067D0

Abstract

A self-closing two-position valve with a single active seal 1 and stepped-cylinder arrangement 2 includes a valve member 3 which moves from a closed position to an open position (see figure 2) when pressure is applied to an inlet, and moves back to the closed position when pressure is removed from the inlet or pressure at the outlet exceeds inlet pressure. The valve member 3 is not resiliently biased towards the open or closed position. The valve may include stops 6, 10 which limit travel of the valve member. Means (not shown) may be included for locking the valve member in the open or closed position. The valve member may include apertures and/or grooves (9, figure 2) which allow fluid flow past the stops when in the open position.

Description

DESCRIPTION. 1.

SNAPSHUT VALVE

This valve is conceived as a very economical unit with a multiplicity of uses which may be configured in different ways and may be incorporated with the unit being controlled. It can operate like a check valve but without a spring and with just one seal, needing no gasket seal or gland seal. Once closed, it requires no pressure to keep it closed and sealed.

In a first embodiment (figure 1), a sliding spool-type valve has a single seal (1) and a stepped body or cylinder bore (2). The moving element or spool (3) has suitable arrangements (12) which allow gas or fluid to enter the said body and apply pressure to the end face of the spool. When the incoming pressure is greater than that pertaining at the outlet, the spool will move across to or stay at the outlet side (figure 2) thus allowing transfer port or ports (7) to feed gas or fluid to the outlet or exit side of the valve (8) whilst sealing the said cylinder from ambient air. In figure 3, the spool has suitable arrangements (9) which allow gas or fluid to then pass across or by the end face of the spool to the outlet of the valve.

When incoming pressure is released or reduced below that of the outlet side of the valve and provided that there is sufficient restriction to the flow through the transfer port or ports, this pressure difference created across the ends of the spool will cause the spool to snap across to the inlet side, closing the valve and thus blocking the transfer port or ports and sealing the valve at the outlet side pressure (figure 1). This version is a one-way valve.

There may be suitable arrangements or stops (6) at each or both ends of the spool or body which keep these faces from butting together which would prevent pressure from acting on the ends of the spool.

In a second embodiment (figures 4 & 5), the spool has a control means whereby the valve can be operated externally which may be but not exclusively an integral spigot or end (4) through which inlet gas or fluid is passed via transfer holes (7) at the internal end as in the first embodiment. In the open position (figure 5), flow is through an annular passage and via a suitable configuration (9) past the other end of the spool to the exit (pressure) end (8) of the valve.

Instead of sliding, the active part of the valve may flex about a centre restraint like an air-bed valve but with the crucial difference that the valve described here can be used for exhausting (deflation) as well.

Either of these two embodiments may be used with an output configuration in which the valve exit has an open end (8), for example but not exclusively into a pneumatic cylinder or pressure vessel and where the inside diameter of the valve end (10) is connected or fixed over a boss or lip or standpipe (11) or such part of this cylinder or vessel as to make a restraint for the spool travel. This embodiment may have for example but not exclusively on the end of the spool a cruciform set of lugs (6) which are inside the larger bore of the stepped body or cylinder as referred to in the first embodiment. These lugs can limit the end of travel when they butt against the said spigot. The gaps between the lugs (9) allow passage of gas or fluid to the exit end of the valve. In the closed position, these same lugs again set the limit of travel of the spool. Alternatively one limit of the spool travel 2.

may be on the outside part of the spool at the input end where the limiter may butt up against the valve casing. In this case the valve casing may be set within the said boss or lip or standpipe.

When input pressure is released, the valve will snap shut if there is sufficient pressure at the exit side, or it may be closed by moving the spigot to the closed position. Any internal pressure will tend to keep it closed but may not be necessary to keep it sealed.

In the second embodiment, if input pressure is increased above the pressure inside the closed valve, it will have no effect. The valve will stay closed until the spool is moved by external means, for example by manually pushing the end of the valve (which may be against this pressure) to enable transfer of air; and can also be shut off by pulling the external end of the spool.

In some configurations, when the valve spool is transiting from open to closed, there will be a very short time when the seal is away from both of its sealing areas. However, there will be minimal fluid leakage because this duration is short and because the annular gap through which fluid can leak is very small. Moreover, the valve itself will tend to snap shut of its own accord under any pressure.

This action is quick because the coefficient of sliding friction is less than that of the static coefficient.

By reversing the configuration and if required adding a reference pressure means, this valve can also be used as an over-pressure relief valve.

By making a carefully-dimensioned lip or recess in the moving element to press against the seal and with optionally an elastic deformable moving element or other means, the valve can be used as a re-settable dump valve; once compressive resistance to the seal and or to the deformable element has been overcome, the spool will snap open past the seal and dump all the pressure.

In Figure 6, the valve may be additionally be configured to be held or locked open or closed or both by the addition for example of screw thread or grooves or splines (13) with for example but not exclusively flat end faces or a bayonet-type lock. The splines may conveniently have stops on the flat ends (14) to give a positive location when the valve is to be held open. Similar means can be arranged to keep or hold the valve closed.

The valve may be configured for manual operation, for which purpose there may be provided grip means on the valve body and or on the spigot part.

It may easily be configured as a springless supply-on-demand tap (figures 4 & 5) where the inlet part now (11) may be fixed for example but not exclusively to a drum and the outlet (4) is moved to operate the valve. By changing this configuration (figures 7 & 8), the valve can be configured with for example but not exclusively a float or means attached to the valve such that the valve can be opened for example manually and will close automatically when fluid pressure on a float or other means in the receiving vessel or otherwise signals greater effect than the supply pressure. The valve stem may then be rotated to lock it closed as disclosed above (figure 6) or by other means.

None of the above precludes the fitting of a fixed seal at either or both ends of the valve to permit connection to a supply or receiver.

Claims

CLAIMS.SNAPSHUT VALVE1. A springless sliding self-closing two-position valve with a single active seal and stepped body or cylinder-bore arrangement.
2. A springless self-closing two-position valve with a single active seal and stepped body or cylinder-bore arrangement.
3. A valve as in claims 1 or 2 having internal and or external stops to set the limit or limits of traveL
4. A valve as in claims 1, 2 or 3 with open-ended splines or guides or grooves to hold the valve open against pressure if required.
5. A valve as in claims 1, 2 or 3 with an internal thread or other means to hold the valve open against pressure if required.
6. A springless self-closing two-position valve with a single active seal and internal and or external travel stops and with an internal thread or other means to hold the valve open against pressure.
7. A valve as claimed in any claims 1 to 6 with a single seal.
8. A valve as claimed in any claims ito 7 with means for holding the valve open by for example but not exclusively limit stops and or bayonet-type location, or land with blocked end, means.
9. A valve as claimed in any claims ito 8 with manual movement or manual operating means.
10. A valve as claimed in any claims 1 to 9 with means to hold the valve closed instead of open, or to hold open or closed as required.
ii. A springless sliding self-closing two-position valve with a single seal and internal and or external travel stops.
12. A springless self-closing two-position valve with a single seal and internal and or external travel stops.
13. A springless sliding self-closing two-position valve with a single seal.
14. A springless self-closing two-position valve with a single seal.
15. A self-closing sliding two-position valve with a single active seal.
16. A self-closing sliding two-position valve with a single seal.
17. A self-closing two-position valve with a single seal.
18. A valve as in any of the above claims configured as a valve which is self-opening at a set condition or as a dump valve.
19. A valve as in any of the above claims ito 17 configured as a pressure relief valve.
20. A valve as in any of the above claims ito 17 configured as a pressure supply valve.
21. A valve as in any of the above claims ito 17 configured as a pressure balance valve.
22. A valve as in any of the above claims 1 to 17 configured as a pump valve or inflation valve.
23. A valve as in any of the above claims ito 17 configured as a supply-on-demand valve.
24. A valve as in any of the above claims and generally configured with one seal or gland.