Fluid cylinder with embedded positioning sensor

A piston and rod assembly, comprising:

• a rod having an axial passage and an opening at one end adapted for telescopically receiving a sensor element;
• a piston having first and second axial ends, the rod extending from a first axial end of the piston and the second axial end including a surface adapted for abutment;
• an element interactive with the sensor element positionable in or in close proximity to the opening, and a retaining element, the element interactive with the sensor element being retained in position by the retaining element;
• and
• a piston retaining element, the piston being retained on the rod adjacent to said end of said rod, wherein the retaining element and the piston retaining element being recessed within the second axial end of said piston.

A fluid cylinder, comprising:

• a cylinder body including a cylindrical inner cavity having a longitudinal axis therethrough;
• a member enclosing an axial end of the internal cavity, the member having a sensor port therethrough extending between an internal opening communicating with the internal cavity and an external opening;
• a piston and rod assembly disposed for axial movement in the internal cavity of the cylinder body and including an axial passage extending therein or therethrough;
• and
• a magnetostrictive sensor mounted in the internal opening of the sensor port and having a pressure pipe extending into the internal cavity of the cylinder body and telescopically received in the passage in the rod, a magnet mounted on the rod in proximity to the pressure pipe, and a sensor electronics module being encased within a portion of the fluid cylinder not including the piston and rod assembly, the sensor being operable for sensing an axial distance of the magnet from the sensor and outputting a signal representative of the distance to the sensor electronics module, the sensor electronics module including circuitry for receiving the signal, determining an axial position of the piston or the rod therefrom, and outputting a position signal representative of the axial position of the piston or rod.

A cylinder assembly comprising;

• a cylinder and a piston and rod assembly reciprocally disposed within said cylinder, said cylinder including an end portion sealably enclosing an end thereof;
• and
• a position sensor assembly operative to sense a position of said piston and rod assembly and generate an output signal indicative of said position, said position sensor assembly comprising:
• a sensor electronics module encased in said end portion of said cylinder;
• a sensor portion in electrical communication with said sensor electronics module, said sensor portion being configured to register a position of the piston and rod assembly relative said cylinder.