WO1999022164A1

WO1999022164A1 - Valve

Info

Publication number: WO1999022164A1
Application number: PCT/NL1998/000573
Authority: WO
Inventors: Erich Emanuel Toppenberg
Original assignee: Erich Emanuel Toppenberg
Priority date: 1997-10-24
Filing date: 1998-10-05
Publication date: 1999-05-06
Also published as: AU9560498A; NL1007352C2

Abstract

The invention relates to a valve comprising a housing (1) with an inlet port (6) and an outlet port (7), and a closing member (2) which is movable in the housing (1), for opening and closing a communicating conduit between the inlet port (6) and the outlet port (7), while the seal between the closing member and the housing is provided by means of a packing (3). The packing is made from a flexible material that can deform under the influence of the prevailing pressure in the communicative conduit, and the deformation of the packing is limited by the fact that it presses both on the closing member and the housing.

Description

valve

The invention relates to a valve comprising a housing with an inlet port and an outlet port, and a closing member which is movable in the housing, for opening and closing a communicating conduit between the inlet port and the outlet port, while the seal between the closing member and the housing is provided by means of a packing.

EP-A-0 239 987 discloses a device comprising a housing provided with a inlet port and an outlet port for hydraulic fluid, and a movable core member provided with bores. The adjustment of said core member by rotation or by axial displacement opens or closes a communicative passage between the inlet ports and outlet ports. Between the core member and the housing a packing is provided in the form of an O-ring. If the pressure in the communicat- ive conduit between the inlet port and the outlet port rises too much, a packing such as the one known from the prior art , leads to leakage .

It is the object of the invention to provide a valve which is substantially leakage-proof . To this end the valve according to the invention is characterized in that the packing is made from a flexible material that can deform under the influence of the prevailing pressure in the communicative conduit, and in that the deformation of the packing is limited by the fact that it presses both on the closing member and the housing.

The valve according to the invention has the advantage that the seal between the housing and the closing member provided in the housing improves with the increase of pressure in the communicative conduit between the inlet port and the outlet port.

An embodiment that particularly furthers the objective of the invention is one in which the packing comprises a base to which are joined two legs, so that one of the legs presses onto the closing member and the other leg presses onto the housing.

Optimal results are obtained if the legs and the base of the packing form a convex concave surface facing the communicating conduit. The pressure in the communicating conduit is, in accordance with the law of Pascal, the same in all directions, which results in the convex concave shaped surface pressing the legs and the base onto the housing and the closing member respectively in such a manner that an increase in pressure will distribute proportionately over the components of the valve.

An economical manner of manufacturing the valve according to the invention is by making the packing from teflon. The advantage of teflon is that it is resistant to harmful chemical influences and extreme temperature stresses. In addition, the greasy quality of the teflon makes that even under a high pressure load the closing member can move slightly over the packing, while nonethe- less an excellent seal is provided.

In an alternative embodiment of the valve according to the invention the communicating conduit between the inlet port and the outlet port is formed by grooves provided in the circumferential surface of the closing mem- ber, which grooves, in at least one position of the closing member, form a fluid conduit between the inlet port and the outlet port. Such grooves are more easily realizable than the bores in the closing member known from the prior art, thereby offering economical advantages. It is advisable to form the grooves with rounded corners to avoid damage to the packing and to ensure that the sealing effect of the valve according to the invention is maintained for a long time. The grooves may be straight, however they are preferably slightly curved in the circumfer- ential direction of the closing member. This promotes symmetrical loading of the packing, thereby restricting wear. In a preferred embodiment of the valve according to the invention the base of the packing is designed such that at least in the spring-loaded condition said base between the legs of the packing deviates from the housing in a curve, while the two legs press both on the closing member and the housing. This renders the valve according to the invention particularly suitable for application under very high pressures. As a result of such high pres- sures the packing may deform, so that the curve may disappear and the packing comes to lie completely against the housing. Due to this deformation which causes the curve to disappear, the two legs will press with increased pressure on the closing member and the housing, thereby providing an improved sealing effect .

To this end it is further useful if the packing is spring loaded, and a first spring presses against the packing via an inner ring that abuts to the leg pressing on the closing member, at the side of the packing's convex concave surface facing the communicating conduit.

In order to load the packing symmetrically, it is advantageous if a second spring presses onto the packing via an outer ring that abuts to the leg pressing on the housing, at the side of the packing's convex concave surface facing the communicating conduit.

The invention will now be explained in more detail with reference to the drawings, in which

Figs . 1 and 2 show the valve in accordance with a first embodiment of the invention, in the closed and open position;

Fig. 3 shows a detail of the valve according to the invention;

Figs . 4 and 5 show the valve in accordance with a second embodiment of the invention in the closed and open position; and

Fig. 6 shows a cross-sectional view of a closing member of the valve according to the invention.

Similar parts in the Figures are indicated by iden- tical reference numbers.

The valve shown in the Figs. 1, 2 and 3 comprises a housing 1 with an inlet port 6 and an outlet port 7, and also a closing member 2 in the form of an axle which is movable in the housing and serves to open and close a com- municating conduit between the inlet port 6 and the outlet port 7. To this end the axle 2 is provided with a bore 8 which, when the valve is in the open position as shown in Fig. 2, provides communication between the chamber 9 into which an inlet port 6 debouches and a chamber 10, with which the outlet port 7 is connected. In the valve's closed position as shown in Fig. 1, the bore 8 of the axle 2 is moved such that there is no communication between the chamber 9 and the chamber 10. Figs . 4 and 5 show a second embodiment of the valve according to the invention, in which the communicating conduit between the inlet port 6 and the outlet port 7 is not formed by a bore as shown in Figs . 1 and 2 , but by grooves 14 provided in the circumferential surface of the axle 2. Fig. 5 shows that in the valve's open position said grooves 14 provide communication between the chamber 9 into which an inlet port 6 debouches and the chamber 10, with which the outlet port 7 is connected. In Fig. 4 the valve is shown in the closed position in which the axle 2 is moved such that the grooves no longer provide communication between the chambers 9 and 10 into which the inlet port 6 and the outlet port 7 debouch.

In Fig. 6, a cross-sectional view of the axle 2 shows that the grooves 14 have rounded corners so that when the axle 2 is moved between the valve's open and closed position, it will not damage the packing 3.

In order to provide a seal between the axle 2 , which serves as closing member, and the housing 1, a packing 3 is provided which, in accordance with the invention is made from a flexible material, for example, teflon that can deform under the influence of the pressure prevailing in the communicating conduit, that is to say the pressure in the chambers 9 and/or 10. The deformation of the packing 3 is limited by the fact that it presses both on the axle 2 and the housing 1. As can be clearly seen in Figs. 1, 2 and 3, the packing comprises a base 12 (see Fig. 3) and two legs 11 and 13 which are joined with the base 12. Leg 13 presses onto housing 1, while leg 11 presses onto the axle 2. The legs 11 and 13 and the base 12 of the packing 3 have a convex concave surface facing the communicating conduit such as the chamber 9, so that the pressure in the communicating conduit causes the packing 3 to press onto the valve's components with increased force. This ensures the sealing effect in the valve's packing. In the embodiment shown in Figs. 4 and 5, the packing 3 is designed such that at least in the spring-loaded condition, but also in the unloaded condition, the base 12 between the packing's 3 legs 11 and 13, deviates from the housing in a curve, while the two legs 11 and 13 still press both on the axle 2 and the housing 1. This provides the useful effect that when the pressure on the packing 3 increases, the curve disappears so that the base 12 broadens and the legs exert an increased pressure on the axle 2 and the housing 1. This improves the sealing action of the valve's packing 3.

The Figs. 1, 2, 4 and 5 show that the packing 3 is spring loaded. To this end a first spring 15 is provided which presses against the packing 3 and which preferably, as shown in Figs. 4 and 5, loads said packing via an inner ring 16 abutting to the leg 11 that presses on the axle 2 at the side of the packing's 3 convex concave surface facing the communicating conduit. This also improves the sealing effect of the valve's packing 3. In order to load the packing as symmetrically as possible, a second spring 17 is provided which presses onto an outer ring 18 abutting to the leg 13 that presses on the housing 1, at the side of the packing's 3 convex concave surface facing the communicating conduit.

Claims

1. A valve comprising a housing (1) with an inlet port (6) and an outlet port (7) , and a closing member (2) which is movable in the housing (1) , for opening and closing a communicating conduit between the inlet port (6) and the outlet port (7) , while the seal between the closing member and the housing is provided by means of a packing, characterized in that the packing (3) is made from a flexible material that can deform under the influence of the prevailing pressure in the communicative conduit, and in that the deformation of the packing is limited by the fact that it presses both on the closing member (2) and the housing (1) .

2. A valve according to claim 1, characterized in that the packing (3) comprises a base (12) to which are joined two legs (11, 13) , so that one (11) of the legs (11, 13) presses onto the closing member (2), and the other leg (13) presses onto the housing (1) .

3. A valve according to claim 1 or 2 , characterized in that the legs (11, 13) and the base (12) of the packing (3) form a convex concave surface facing the communicating conduit .

4. A valve according to one of the preceding claims, characterized in that the packing is made from teflon.

5. A valve according to one of the claims 1-4, characterized in that the communicating conduit between the inlet port (6) and the outlet port (7) is formed by grooves (14) provided in the circumferential surface of the closing member (2) , which grooves (14) , in at least one position of the closing member (2) , form a fluid conduit between the inlet port (6) and the outlet port (7) .

6. A valve according to claim 5, characterized in that the grooves (14) run at least for a part in the circumferential direction of the closing element (2) .

7. A valve according to claim 5 or 6 , characterized in that the grooves (14) are formed with rounded corners.

8. A valve according to one of the claims 1-7, characterized in that the base (12) of the packing (3) is designed such that at least in the spring-loaded condition said base (12) between the legs (11, 13) of the packing (3) deviates from the housing (1) in a curve (Figs. 4, 5), while the two legs (11, 13) press both on the closing member (2) and the housing (1) .

9. A valve according to one of the claims 3-8, characterized in that the packing (3) is spring loaded, and a first spring (15) presses against the packing (3) via an inner ring (16) that abuts to the leg (11) pressing on the closing member (2), at the side of the packing's (3) convex concave surface facing the communicating conduit.

10. A valve according to claim 9, characterized in that a second spring (17) presses onto the packing (3) via an outer ring (18) that abuts to the leg (13) pressing on the housing (1), at the side of the packing's (3) convex concave surface facing the communicating conduit.