Combined check valve and pressure relief valve

A valve for use in regulating the flow of fluid between a first fluid side and a second fluid side in a hydraulic circuit, comprising:

• a valve body having an aperture extending through the length of the valve body;
• a valve insert sidably positioned within the aperture of the valve body, the valve insert having a first end that is proximate to the first fluid side, and a second end that is proximate to the second fluid side;
• a check poppet attached to the valve insert;
• a relief spring positioned between the valve insert and the check poppet;
• and
• a relief poppet positioned between the relief spring and an opening in the check poppet, wherein the relief poppet is capable of moving away from the opening in the check poppet against the force of the relief spring to an open relief position to permit fluid to pass from the second fluid side to the first fluid side through the opening in the check poppet.

An apparatus for use in regulating the flow of fluid between a first fluid side and a second fluid side of a device, comprising:

• a check valve having a valve body with an aperture extending through the length of the valve body, a valve insert positioned within the aperture of the valve body and a check poppet removably attached to the valve insert, wherein at least a portion of the check poppet is external to the valve body;
• and
• a relief valve having a relief spring positioned between the valve insert and the check poppet, and a relief poppet that is positioned between the relief spring and an aperture on the check poppet;
• wherein the check valve automatically responds when the fluid pressure in the first fluid side is higher relative to the fluid pressure in the second fluid side by a predetermined amount to move the check poppet, thereby forming a gap between the check poppet and the valve body and a check flow passage between the first fluid side and the second fluid side to allow fluid to pass from the first fluid side to the second fluid side through the check flow passage;
• and
• wherein the pressure relief valve automatically responds when the fluid pressure in the second fluid side is higher relative to the fluid pressure in the first fluid side by a predetermined amount determined in part by the relief spring, to open a relief flow passage formed in the check poppet to permit fluid to pass from the second fluid side to the first fluid side through the relief flow passage.

A valve for use in regulating the flow of fluid between a first fluid side and a second fluid side in a hydraulic circuit, comprising:

• a valve body having an aperture extending through the length of the valve body;
• a valve insert having a first end and a second end, the second end of the valve insert forming a valve stop;
• a check poppet attached to the first end of the valve insert, wherein the attached check poppet and valve stop cooperate to slidably retain the valve insert within the aperture;
• and a check spring positioned between the valve body and the valve stop of the valve insert;
• wherein the valve stop is adapted to have a length that is greater than the diameter of the aperture of the valve body to engage the valve body and to limit the movement of the check poppet in relation to the valve body.

A valve for use in regulating the flow of fluid between a first fluid side and a second fluid side in a hydraulic circuit, comprising:

• a valve body having an aperture extending through the length of the valve body;
• a valve insert having a first end and a second end and comprising a first opening capable of creating a fluid flow between the first fluid side and the second fluid side and a second opening capable of creating a fluid flow between the first fluid side and the second fluid side, the second end of the valve insert forming a valve stop;
• a check poppet attached to the first end of the valve insert, wherein the attached check poppet and valve stop cooperate to slidably retain the valve insert within the aperture;
• and a check spring positioned between the valve body and the valve stop of the valve insert.