Hydraulic coupler

Claim 2

In a hydraulic coupler attachment device including a coupler body having an interior passageway, a manually controllable inlet check valve, and a manually operable outlet check valve in said interior passageway, said inlet check valve and said outlet check valve defining a chamber on the interior of said coupler body between said valves, the improvement comprising a movable wall defining a portion of said chamber, and means exterior of the chamber operatively associated with said movable wall to move the wall to enlarge said chamber at selected times.

Claim 3

The hydraulic coupler of claim 1 wherein said means exterior of said chamber comprises manual control means including cam means defining cam surfaces controlling positions of said inlet and outlet check valves.

Claim 4

The hydraulic coupler of claim 2 wherein said means defining cam surfaces is a rotatable cam having a first position wherein the inlet valve is held open, said cam being rotatable to a second position wherein the inlet valve is permitted to close and said cam being rotatable to a third position wherein said cam permits said movable wall to move to enlarge the size of said chamber when said chamber is under pressure.

Claim 5

The coupler assembly of claim 3 and means operatively associated with said outlet check valve positioned between said cam and said outlet check valve comprising a mechanical noncompressible means acting between said outlet check valve and said cam to hold said outlet check valve in a selected position when the cam is in a high cam position, said movable wall means comprising a piston wall surrounding said mechanical means, said piston wall being sealed to define a separate chamber filled with compressible fluid isolated by said piston wall from said chamber in the coupler body.

Claim 6

The combination as specified in claim 4 wherein said piston wall has a head end of a larger diameter than the main portion of said piston wall, said sealing means including a seal at said head end sealing the chamber in said coupler body from the chamber filled with compressible fluid.

Claim 7

The combination as specified in claim 4 wherein said cam includes surfaces adjacent opposite ends thereof of size to engage portions of said piston wall to permit said piston wall to be controlled by said cam for movement to permit enlarging said chamber in said coupler body.

Claim 8

The combination as specified in claim 4 wherein said coupler body includes releasable means for holding a coupler nipple in position at one end thereof, a coupler nipple mounted in said releasable means, said coupler nipple including a check valve mating with the outlet check valve and being urged to engage said outlet check valve to move said outlet check valve to an open position, said mechanical means permitting said outlet check valve to move to said open position but not substantially beyond the open position when the cam is in its first position, whereby both the check valve in said coupler nipple and said outlet check valve are held open.

Claim 9

The combination as specified in claim 7 wherein said check valve in said coupler nipple is designed to check flow from said coupler nipple toward said inlet check valve in said coupler body.

Claim 10

A coupler assembly including a body member having a through bore, means at one end of said body member for holding a coupler nipple check valve in position thereon, means on the interior of said body member defining an inlet check valve to check flow from the inlet end toward said coupler nipple when in closed position, means on said body member defining an outlet check valve to check flow from the inlet end toward said coupler nipple when in closed position, a cam member mounted on said coupler body and being positioned so that in a high cam position said cam member holds said inlet check valve in an open position, means acting between said cam member and said outlet check valve to prevent said outlet check valve from moving beyond a selected open position when the cam member is in the high cam position, said outlet check valve cooperating with a coupler nipple attached to said coupler body so the outlet check valve is held in an open position when the cam member is in high cam position, said outlet check valve comprising a check valve member mounted in a chamber defined between the inlet check valve and the outlet check valve, said coupler assembly including movable wall means forming a portion of said chamber, and means acting between said cam member and said movable wall means to permit said movable wall means to vary the size of said chamber in response to movement of said cam member.

Claim 11

A coupler assembly including a body member having a through bore, means at one end of said body member for holding a coupler nipple check valve in position thereon, means on the interior of said body member defining an inlet check valve to check flow from the inlet end toward said coupler nipple when in closed position, means on said body member defining an outlet check valve to check flow from the inlet end toward said coupler nipple when in closed position, a cam member mounted on said coupler body and being positioned so that in a high cam position said cam member holds said inlet check valve in an open position, means acting between said cam member and said outlet check valve to prevent said outlet check valve from moving beyond a selected open position when the cam member is in the high cam position, said outlet check valve cooperating with a coupler nipple attached to said coupler body so the outlet check valve is held in an open position when the cam member is in high cam position, said outlet check valve comprising a check valve member mounted in a chamber defined between the inlet check valve and the outlet check valve, said coupler assembly including movable wall means forming a portion of said chamber, and means acting between said cam member and said movable wall means to permit said movable wall means to vary the size of said chamber in response to movement of said cam member.

Claim 12

The combination as specified in claim 9 wherein said movable wall means comprises an annular wall slidably mounted in the through bore of said body member, sealing means cooperating with said movable wall to said chamber in which the outlet check valve is mounted.

Claim 13

The combination as specified in claim 10 wherein said sealing means are positioned to provide an area pressure not significantly higher than atmospheric pressure on a side of the sealing means opposite said chamber, whereby pressure in said chamber will cause said movable wall means to tend to move to expand the size of said chamber, said cam restraining movement of said movable wall except in a selected cam position.