Protection of a seal element

A hydraulic coupling which comprises:

• a tubular body;
• an internal passage which extends through the body between a first opening and a second opening;
• a valve seat which is formed in a part of the passage proximate the first opening;
• a valve member which is positioned within the passage;
• a first sealing element which is supported on the valve member proximate the valve seat;
• wherein the valve member is movable between a closed position in which the first sealing element is engaged with the valve seat and an open position in which the first sealing element is separated from the valve seat;
• wherein the valve member comprises an actuator pin which extends axially through the first opening when the valve member is in its closed position;
• a sleeve member which is positioned around at least a portion of the valve member;
• wherein the sleeve member is axially movable relative both to the body and the valve member between a first position in which the sleeve member substantially covers the first sealing element and a second position in which the sleeve member is substantially retracted from the first sealing element to thereby enable the sealing element to seal against the valve seat;
• and
• wherein the valve member is moved from its closed position to its open position and the sleeve member is moved from its second position to its first position in response to an external force acting on the actuator pin.

In combination with a valve which comprises a body, a flow passage which extends through the body, a valve seat which is formed in a portion of the flow passage, a valve member which is positioned in the flow passage proximate the valve seat and a sealing element which is supported on the valve member, the improvement comprising a protective device for the sealing element which includes:

• a valve retainer which is slidably supported in the flow passage and which includes a cylindrical sleeve portion in which the valve member is slidably supported;
• wherein the valve member is movable relative to both the body and the sleeve portion between a closed position in which the sealing element is engaged with the valve seat and an open position in which the sealing element is separated from the valve seat;
• wherein in the open position of the valve member a distal part of the sleeve portion substantially engages the sealing element and in the closed position of the valve member the distal part of the sleeve portion is substantially disengaged from the sealing element;
• and
• wherein the protective device further comprises a first spring which is positioned between the valve retainer and the valve member and which urges the valve member towards the closed position.