Abstract: A hydraulic spool lock with a hydraulic spool housing, first and second hydraulic spools mounted within the hydraulic spool housing for independent selective movement with respect to the hydraulic spool housing, and a lock plunger movable mounted to the hydraulic spool housing. The present invention allows independent movement of the spools with respect to the hydraulic spool housing when the hydraulic spool lock is in the unlocked position. The present inventions prevents movement of the spools with respect to the hydraulic spool housing when the hydraulic spool lock is in a locked position.

Abstract: A hydraulic cylinder assembly includes an electrical sensing device for sensing the relative position of a hydraulic piston within the cylinder. The sensor assembly includes a spool which is connected to one end of a wire that extends outside the cylinder. The spool may be rotated to take up any slack in the wire. Also, the wire is connected to a header assembly in the wall of the cylinder. The header assembly includes an internal member to which the wire is connected that does not rotate with respect to the outer header member during the threading of the outer header member into the wall of the cylinder.

Abstract: The wire lock is provided for holding a stop ring on the outer surface of a cylinder. The stop ring includes a counterbore at one end thereof. The counterbore is positioned above an annular groove in the outer circumference of the cylinder. The wire lock is inserted into the registered counterbore and annular groove so as to prevent the stop ring from moving axially on the outer surface of the cylinder. The wire lock is accessible and visible from one axial end of the stop ring.

Abstract: The double acting hydraulic piston and cylinder assembly of the present invention utilizes a unique fastening mechanism for fastening the piston to the cylinder rod. The piston has a rod receiving opening through which the piston rod is fitted. The piston includes a piston groove which is aligned with an annular rod groove in the outer surface of the rod. Extending from the outer circumference of the piston inwardly to the piston groove is an access opening, through which a retaining wire is inserted. The retaining wire is wrapped around the piston rod and fits within both the piston groove and the rod groove so as to hold the piston against longitudinal movement with respect to the rod.The method of the present invention comprises inserting the retainer wire through the access opening in the piston and rotating the piston until the wire wraps around the piston rod.

Abstract: The poppet trip device of the present invention is adapted for hydraulic cylinder units having a poppet axially movable within a poppet sleeve extended through the piston of the hydraulic cylinder unit. A head end of the poppet extends outwardly from the piston for engaging the head end of the cylinder in response to movement of the piston to the cylinder head end whereby the poppet is unseated and fluid communication is established through the poppet sleeve. Since the piston is spaced from the free end of the piston rod, however, engagement of the piston rod with the base end of the cylinder leaves the base end of the poppet spaced from the cylinder base end. The trip device or contact member of the present invention therefore is supported between the cylinder base end and piston for engaging the base end of the poppet in response to movement of the piston rod to the cylinder base end whereby the poppet is unseated and fluid communication is established through the poppet sleeve.