Balancing plate—shuttle ball

1. In a hydraulic device utilizing rotor valving with inner and outer commutation grooves in an orbiting rotor interconnecting two ports to expanding and contracting gerotor cells through a stationary manifold in the housing on pressurizing one side of the rotor away from the manifold,

the improvement of a pressure compensation mechanism, said pressure compensation mechanism including a balancing plate, said balancing plate being connected to the housing between the rotor and the housing on the other side of the rotor than the manifold,

said balancing plate having a pressure chamber, a shuttle valve compartment, said shuffle valve compartment being fluidically connected to said pressure chamber, said shuffle valve compartment having two openings, said two openings being connected to the two ports respectively,

a shuttle valve, said shuttle valve being in said shuttle valve compartment, said shuttle valve being moveable within said compartment to seal one of said two openings upon relative pressurization of the other of said two openings to provide for the pressurization of said pressure chamber and thus pressure compensation for the device.

2. The pressure compensation mechanism of claim 1 characterized in that said balancing plate includes two individual adjoining disks with the pressure chamber therebetween.

3. The pressure compensation mechanism of claim 2 characterized in that one of said two openings of the shuttle valve compartment is in one of said two disks with the other of said two openings of the shuttle compartment being the other of said two disks.

4. The pressure compensation mechanism of claim 1 characterized in that one of the two ports connects to one of said two openings of the shuttle compartment through the inner commutation groove.

5. The pressure compensation mechanism of claim 1 characterized in that one of the two ports connects to one of said two openings through the outer commutation groove.

6. The pressure compensation mechanism of claim 1 wherein the hydraulic device has an end plate and characterized in that both of the two ports are in the end plate and the stationary manifold is adjacent to the end plate.

7. The pressure compensation mechanism of claim 2 characterized by the addition of a seal between said adjoining disks inside said pressure chamber.

8. The pressure compensation mechanism of claim 2 characterized by the addition of a seal between said adjoining disks outside said pressure chamber.

9. The pressure compensation mechanism of claim 4 wherein the hydraulic device has a thrust bearing for its rotating shaft and characterized in that one port opening connection is through the thrust bearing.

10. The pressure compensating mechanism of claim 5 characterized by the addition of dimples, said dimples being in the rotor adjoining the outer commutation groove, and said dimples sweeping over said one of said two openings.

11. The pressure compensating mechanism of claim 1 characterized in that said pressure chamber has a radial extent and the cross section of said shuttle valve compartment intersecting said radial extent of said pressure chamber.

12. The pressure compensating mechanism of claim 10 wherein the rotor has lobes with valleys and characterized in that said dimples are located in pairs at the valleys at the root of the rotor lobes respectively.

13. The pressure compensating mechanism of claim 5 characterized by the addition of a further commutation groove for said one of said two openings.

14. The pressure compensating mechanism of claim 13 characterized in that said further commutation groove is of varying width.

15. The pressure compensating mechanism of claim 13 characterized in that said further groove is etched into one of said discs.

16. The pressure compensating mechanism of claim 1 characterized in that said balancing plate is of at least two sequential plates.

17. The pressure compensating mechanism of claim 16 characterized in that said at least two sequential plates are of single cross section respectively.

18. In a hydraulic device utilizing rotor valving with inner and outer commutation grooves in an orbiting rotor interconnecting two ports to expanding and contracting gerotor cells through a stationary manifold in the housing on pressurizing one side of the rotor away from the manifold,

each of the inner and outer commutation grooves being fluidically connected to a port respectively,

the improvement of a pressure compensation mechanism, said pressure compensation mechanism including a balancing plate, said balancing plate being connected to the housing between the rotor and the housing on the other side of the rotor than the manifold,

said balancing plate having a pressure chamber, a shuffle valve compartment, said shuffle valve compartment being fluidically connected to said pressure chamber, said shuttle valve compartment having two openings,

one of said two opening connecting through the inner commutation groove to one of the ports, the other of said two openings connecting through the outer commutation groove to the other of the ports,

a shuffle valve, said shuffle valve being in said shuttle valve compartment, said shuttle valve being moveable within said compartment to seal one of said two openings upon relative pressurization of the other of said two openings to provide for the pressurization of said pressure chamber and thus pressure compensation for the device.

19. The pressure compensation mechanism of claim 18 characterized in that said balancing plate includes two individual adjoining disks with the pressure chamber therebetween.

20. The pressure compensation mechanism of claim 19 characterized in that one of said two openings of the shuttle valve compartment is in one of said two disks with the other of said two openings of the shuttle compartment being the other of said two disks.

21. The pressure compensating mechanism of claim 18 characterized by the addition of dimples, said dimples being in the rotor adjoining the outer commutation groove, and said dimples sweeping over said one of said two openings.

22. The pressure compensating mechanism of claim 18 characterized in that said pressure chamber has a radial extent and the cross section of said shuttle valve compartment intersecting said radial extent of said pressure chamber.

23. In a hydraulic device utilizing rotor valving with inner and outer commutation grooves in an orbiting rotor interconnection two ports to expanding and contracting gerotor cells through a stationary manifold in the housing on one side of the rotor,

the improvement of a pressure compensation mechanism, said pressure compensation mechanism including two balancing plates, said balancing plates being connected to the housing between the rotor and the housing on the other side of the rotor than the manifold,

said balancing plates defining a pressure chamber therebetween, said pressure chamber having a radial extent,

a shuttle valve compartment, said shuttle valve compartment having a cross section fluidically connected to said pressure chamber, said shuttle valve compartment having two openings, said two openings being connected to the two ports through the inner and outer commutation grooves in the rotor for constant flow therebetween respectively,

a shuttle valve, said shuffle valve being in said shuttle valve compartment, and said shuttle valve being moveable within said compartment to seal one of said two openings upon relative pressurization of the other of the two openings to provide for the pressurization of said pressure chamber and thus pressure compensation for the device.

24. The pressure compensation mechanism of claim 23 wherein the manifold has a central opening and characterized by the addition of a flange, said flange extending off of the outer surface of the wobblestick,

a groove, said groove being in said housing surrounding the wobblestick, said flange engaging said groove to retain the wobblestick in position in respect to the plane of the opening in the manifold,

and the opening in the manifold having a diameter greater than the diameter transcribed by the adjacent end of the wobblestick.

25. The pressure compensation mechanism of claim 23 wherein the housing has an end plate substantially perpendicular to the rotating axis of the input/output shaft and characterized in that the two ports are in the end plate.