Claims
- 1. An electrohydraulic valve pilot stage for controlling differential pressure comprising:
a housing for protecting the valve; a first inlet capable of connection to a first fluid supply; a second inlet capable of connection to a second fluid supply; a first nozzle fluidly connected to the first inlet for receiving fluid from the first fluid supply; a second nozzle fluidly connected to the second inlet for receiving fluid from the second fluid supply; a baseplate attached to the housing and the nozzles; a restraining member attached to the base plate at a position between the first nozzle and the second nozzle; a pivot pin; a flapper restrained by the restraining member and having a first end and a second end, the flapper pivotably mounted on the pivot pin; a null adjust pin mounted to the housing in a pivot pin contact capable position for adjusting the position of the ends of the flapper relative to the nozzles.
- 2. The electrohydraulic valve pilot stage of claim 1 wherein the null adjust pin is a finely threaded screw.
- 3. The electrohydraulic valve pilot stage of claim 1 wherein the null adjust pin straddles the flapper.
- 4. The electrohydraulic valve pilot stage of claim 1 wherein the center of the null adjust pin and the center of the pivot pin contact.
- 5. The electrohydraulic valve pilot stage of claim 1 further comprising a locking nut mounted on the null adjust pin.
- 6. The electrohydraulic valve pilot stage of claim 1 wherein the null adjust pin is press fit against the pivot pin.
- 7. A single-adjustment dual-null pressure setting for an electrohydraulic valve having a first nozzle and a second nozzle mounted on a baseplate, a restraining member attached to the baseplate between the first nozzle and the second nozzle, a flapper pivotably mounted on the restraining member, the flapper having a first end and a second end, the first end of the flapper capable of pivoting to a position such that the distance between the first end of the flapper and the first nozzle is less than the distance between the second end of the flapper and the second nozzle and the flapper capable of pivoting to a position such that the distance between the second end of the flapper and the second nozzle is less than the distance between the first end of the flapper and the first nozzle comprising:
a pin means for simultaneously adjusting the position of the first end of the flapper relative to the first nozzle and the second end of the flapper relative to the second nozzle.
Parent Case Info
[0001] This is a continuation-in-part of co-pending U.S. application Ser. No. 09/728,964, filed Dec. 4, 2000, which is incorporated by reference herein in its entirety.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09728964 |
Dec 2000 |
US |
Child |
09862060 |
May 2001 |
US |