This invention relates to control valves for controlling fluid flow.
A valve of this kind is known from U.S. Pat. No. 5,267,585, where an elastomeric ball-shaped element is placed inside a control chamber of a flow control valve. By pressing this ball-shaped elastomeric element it will deform, and hereby reduce the flow volume from an inlet passage to an outlet passage in the valve body. Completely pressing the element will completely block the flow volume, whereby the valve will be closed.
The valve disclosed in U.S. Pat. No. 5,267,585 consists of a number of different parts, which has to be assembled to form the valve. Also the valve will be fully open in an unactivated situation, and the fluid flow will have no impact on the degree of opening. A limitation of the flow will thus need a separate valve connected in a serial matter with the flow through the control valve.
A flow control valve will usually influence the degree of flow by a relative movement between a valve member and valve body, as is the case with the valve of U.S. Pat. No. 5,267,585. In the following flow control function is to be understand as any controlled influence the flow control valve will give to the degree of fluid flow, either due to the rate of fluid flow itself or due to an activation of the valve.
It is an object of this invention to simplify the manufacturing of a control valve. It is a further object of this invention to provide a control valve, which will be closed in an unactivated situation. It is yet a further object of this invention to provide a control valve where the fluid flow will influence the degree of opening of the control valve.
The object of this invention is achieved in that flow forces from fluid communicated from one of the fluid passages to the other of the fluid passages will act on the elastomeric element and hereby form at least a part of the flow control function. Hereby is achieved that limitations in rate of fluid flow or in direction of fluid flow are made as self-acting controls inside the control valve, obtained by proper dimensioning of the elements of the valve.
Preferably the level of the flow forces, needed to perform at least a part of the flow function, is lower from the fluid outlet passage to the fluid inlet passage, than from the fluid inlet passage to the fluid outlet passage. Hereby is achieved that a flow rate restriction and a non-return function is obtained inside one valve and by only one closing or restriction member.
In one embodiment of the invention only the flow forces forms the flow control function. Hereby is obtained that a self-acting flow direction control valve can be made very simple.
In another embodiment of the invention, an actuating member is fixed to the elastomeric element, and the flow control function is, in addition to being formed by the flow forces, formed by activating the actuating member. Hereby is achieved that an external control function is added to the valve, however still using only one closing or restriction member.
Preferably the elastomeric element, when the actuating member is not activated, prevents the fluid inlet passage from being in fluid communication with the fluid outlet passage. This will give a normally closed valve, meaning a valve, which is closed when no forces are applied to the valve.
Preferably the control chamber, when the actuating member is not activated, is completely filled by the elastomeric element. Hereby is achieved that the elastomeric element can be moulded inside the control chamber, whereby production of the valve is very simple.
In one embodiment of the invention the elastomeric element, when the actuating member is activated, will be influenced by the flow forces, and by exceeding a certain level of flow forces will separate the fluid outlet passage from fluid communication with the control chamber. Hereby is obtained that an excessive flow rate will lead to a closing of the valve, whereby flow is prevented until normal pressure conditions between inlet and outlet of the valve is obtained.
Now having described the invention in general terms, detailed embodiments of the invention is to be described with reference to the drawings:
FIG. A is a sectional view of
Reference numbers on each figure is kept identical for equivalent elements. This means that following reference list will indicate elements in all figures where the reference is used.
Turning now to
An activating member 7 is fixed by moulding inside the elastomeric element, and is extending to the external of the valve body. A supporting member 8 is placed on the side of the valve body where the actuating member is extending, hereby giving an additional support for the elastomeric element against the influence from activating of the actuating member. The supporting member 8 is mounted to the valve body by means of screws, indicated as position 9.
As the elastomeric element is moulded inside the valve body, the control chamber is completely filled with the elastomeric element. Fluid is thus unable to flow from the inlet passage 2 to the outlet passage 3, or reverse, when the actuating member is inactivated like in
Sectional view 1A-1A of
Most elastomeric materials have a constant volume. Therefore, contracting of an elastomeric element at one position means expanding of the same elastomeric element at another position. On
As no fluid will be contained inside the control chamber when the actuating member is not activated, the valve offers a possibility of exact dosage of a fluid from inlet passage 2 to outlet passage 3.
An additional function of the control valve can be explained from
The pulling actuator for activating the actuating member could be substituted by a pushing actuator. The fixing point for the actuating member in the elastomeric element must be optimised for either pulling or pushing, but contraction of the elastomeric element in the area where the fluid passages 2 and 3 are connected to the control chamber will occur by pulling as well as by pushing.
The level at which the non-return function and the flow restriction function will be activated depends on the position and the geometry of the control part 14 of the elastomeric element 4. Placed concentric in the control chamber the non-return function and the flow restriction function will be identically, and moving the control part 14 to a more and more eccentric position will give more and more distance between the level at which the two functions are activated.
While the present invention has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this invention may be made without departing from the spirit and scope of the present invention.
Number | Date | Country | Kind |
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PA 2002 01350 | Sep 2002 | DK | national |
This application is entitled to the benefit of and incorporates by reference essential subject matter disclosed in international Patent Application No. PCT/DK2003/000593 filed on Sep. 12, 2003 and Danish Patent Application No. PA 2002 01350 filed on Sep. 13, 2002.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/DK03/00593 | 9/12/2003 | WO | 5/31/2005 |