GB2052018A - Non-return Valves - Google Patents

Abstract

A non-return valve has two apertured discs 6 and 7 superposed in a body 1 with the apertures 9, 10 of each disc out of register and overlap with those of the other. One of the discs 7 is adapted to flex away from the other disc 6 in response to fluid pressure applied thereto through the apertures 10 of the other disc, thereby allowing fluid to flow through the apertures of the two discs in one sense of direction. In response to pressure applied to the flexible disc 7 in the opposite sense, however, it bears against the other disc 6 to close the apertures 9, 10 of both discs and thereby prevent fluid flow in the opposite sense of direction. <IMAGE>

Description

SPECIFICATION Non-return Valves This invention relates to non-return valves for fluids, that is to say for liquids or gases.

It is one object of the present invention to provide a non-return valve of simple and economic construction.

According to one aspect of the present invention a non-return valve comprises two apertures discs that are superposed in a body with the one or more apertures of each disc out of register and overlap with the one or more apertures of the other; a first of the discs being adapted to flex away from the second disc in response to fluid pressure applied thereto through the one or more apertures of the second disc and thereby allow fluid flow through the apertures of the two discs in the direction from the second to the first disc, and in response to pressure applied in the reverse sense to bear against the second disc and thereby block fluid flow through the two discs in the direction from the first to the second disc.

The two discs may be superposed concentrically and in these circumstances the said first disc preferably has a central aperture. The said second disc may then have a plurality of apertures distributed in a ring about its centre so hat they en cle, without overlap, the central aperture of the first disc when the two discs are superposed.

A non-return valve in accordance with the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:-- Figure 1 is a sectional side elevation of part of a body incorporating the non-return valve; and Figures 2 and 3 illustrate operation of the nonreturn valve of Figure 1.

Referring to Figure 1, the body 1 of the valve has three main bores machined therein, namely an inlet bore 2, an outlet bore 3 and a short bore 4 interconnecting the other two. The bore 4 has a slightly smaller diameter than that of the outlet bore 3 so that an annular shoulder 5 is formed between them. A rigid disc 6, for example of metal, is a close fit within the bore 3 and is urged hard against the shoulder 5 by a resilient, flexible disc 7. The disc 7, which is for example of rubber, is of larger diameter than the disc 6 and is sprung into an annular groove 8 machined from the wall of the bore 3.

The two concentrically superposed discs 6 and 7 are apertured, the disc 7 having a single, central aperture 9 and the disc 6 a plurality of apertures 10 out of register and overlap with the aperture 9.

More particularly, the apertures 10 are disposed in a ring about the disc centre so that they encircle the central aperture 9 of the disc 7.

The disc 7 is flexible away from the disc 6 when fluid pressure is applied to it through the apertures 10. Thus when, as illustrated by Figure 2, the inlet pressure exceeds the outlet pressure, the consequent flexing of the disc 7 allows fluid to flow through the aperture 9 from the apertures 10, and into the outlet bore 3. If, on the other hand, the outlet pressure exceeds the inlet pressure, so that the resultant pressure differential on the disc 7 is reversed as illustrated by Figure 3, the disc 7 bears tightly against the disc 6 to seal the apertures 9 and 10 and thereby block communication through the discs 6 and 7 in this reverse direction.

The non-return valve described has the merit of very simple construction and, being frictionless, is potentially both efficient and reliable. The arrangement for retaining the two discs requires only shallow bores and eliminates the need for the body to be in two or more parts.

The valve can be provided as an individual component, or the bores for the valve can be provided integrally in the body of another device such as a pressure controller, stop valve or fluid line coupling when a non-return function is to be provided in relation to that device.

Claims

1. A non-return valve comprising two apertured discs that are superposed in a body with the one or more apertures of each disc out of register and overlap with the one or more apertures of the other; a first of the discs being adapted to flex away from the second disc in response to fluid pressure applied thereto through the one or more apertures of the second disc and thereby allow fluid flow through the apertures of the two discs in the direction from the second to the first disc, and in response to pressure applied in the reverse sense to bear against the second disc and thereby block fluid flow through the two discs in the direction from the first to the second disc.

2. A non-return valve according to claim 1 wherein the two discs are superposed concentrically, the first disc having a central aperture and the second disc having a plurality of apertures distributed in a ring about the centre of the disc so that they encircle, without overlap, the central aperture of the first disc.

3. A non-return valve according to claim 1 or claim 2 wherein the two discs are superposed concentrically, the first disc being retained peripherally in an annular groove in the body and the first disc retaining the second disc peripherally against an annular shoulder in the body.

4. A non-return valve substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Non-return Valves This invention relates to non-return valves for fluids, that is to say for liquids or gases. It is one object of the present invention to provide a non-return valve of simple and economic construction. According to one aspect of the present invention a non-return valve comprises two apertures discs that are superposed in a body with the one or more apertures of each disc out of register and overlap with the one or more apertures of the other; a first of the discs being adapted to flex away from the second disc in response to fluid pressure applied thereto through the one or more apertures of the second disc and thereby allow fluid flow through the apertures of the two discs in the direction from the second to the first disc, and in response to pressure applied in the reverse sense to bear against the second disc and thereby block fluid flow through the two discs in the direction from the first to the second disc. The two discs may be superposed concentrically and in these circumstances the said first disc preferably has a central aperture. The said second disc may then have a plurality of apertures distributed in a ring about its centre so hat they en cle, without overlap, the central aperture of the first disc when the two discs are superposed. A non-return valve in accordance with the present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:-- Figure 1 is a sectional side elevation of part of a body incorporating the non-return valve; and Figures 2 and 3 illustrate operation of the nonreturn valve of Figure 1. Referring to Figure 1, the body 1 of the valve has three main bores machined therein, namely an inlet bore 2, an outlet bore 3 and a short bore 4 interconnecting the other two. The bore 4 has a slightly smaller diameter than that of the outlet bore 3 so that an annular shoulder 5 is formed between them. A rigid disc 6, for example of metal, is a close fit within the bore 3 and is urged hard against the shoulder 5 by a resilient, flexible disc 7. The disc 7, which is for example of rubber, is of larger diameter than the disc 6 and is sprung into an annular groove 8 machined from the wall of the bore 3. The two concentrically superposed discs 6 and 7 are apertured, the disc 7 having a single, central aperture 9 and the disc 6 a plurality of apertures 10 out of register and overlap with the aperture 9. More particularly, the apertures 10 are disposed in a ring about the disc centre so that they encircle the central aperture 9 of the disc 7. The disc 7 is flexible away from the disc 6 when fluid pressure is applied to it through the apertures 10. Thus when, as illustrated by Figure 2, the inlet pressure exceeds the outlet pressure, the consequent flexing of the disc 7 allows fluid to flow through the aperture 9 from the apertures 10, and into the outlet bore 3. If, on the other hand, the outlet pressure exceeds the inlet pressure, so that the resultant pressure differential on the disc 7 is reversed as illustrated by Figure 3, the disc 7 bears tightly against the disc 6 to seal the apertures 9 and 10 and thereby block communication through the discs 6 and 7 in this reverse direction. The non-return valve described has the merit of very simple construction and, being frictionless, is potentially both efficient and reliable. The arrangement for retaining the two discs requires only shallow bores and eliminates the need for the body to be in two or more parts. The valve can be provided as an individual component, or the bores for the valve can be provided integrally in the body of another device such as a pressure controller, stop valve or fluid line coupling when a non-return function is to be provided in relation to that device. Claims

1. A non-return valve comprising two apertured discs that are superposed in a body with the one or more apertures of each disc out of register and overlap with the one or more apertures of the other; a first of the discs being adapted to flex away from the second disc in response to fluid pressure applied thereto through the one or more apertures of the second disc and thereby allow fluid flow through the apertures of the two discs in the direction from the second to the first disc, and in response to pressure applied in the reverse sense to bear against the second disc and thereby block fluid flow through the two discs in the direction from the first to the second disc.

2. A non-return valve according to claim 1 wherein the two discs are superposed concentrically, the first disc having a central aperture and the second disc having a plurality of apertures distributed in a ring about the centre of the disc so that they encircle, without overlap, the central aperture of the first disc.

3. A non-return valve according to claim 1 or claim 2 wherein the two discs are superposed concentrically, the first disc being retained peripherally in an annular groove in the body and the first disc retaining the second disc peripherally against an annular shoulder in the body.

4. A non-return valve substantially as hereinbefore described with reference to the accompanying drawings.