Abstract: A pin puller comprising a piston having a pull shaft extending from a cylinder in which the piston is slidable, is actuated by an explosive charge contained within a cartridge disposed laterally of the cylinder. The charge, when ignited, develops a pressurized gas which is directed into the cylinder through a lateral port therein, and acts against the piston to move it in a direction to exert a pull upon the shaft and a pull-actuated device connected thereto.

Abstract: A method of repairing arthritic joints in which the bone surfaces of a knee, hip, shoulder, elbow or other articulation are cleaned of the inflammation caused by the arthritis without removing any of the bone of the joint, and then inserting into the joint a thin, dished bearing member of woven, high tensile strength material impregnated with high molecular weight polyethylene or equivalent material, and cementing one face thereof to the cleaned surface of the bone of one of the joint members, the opposite face of the bearing member being extremely smooth and polished so as to slide easily against the cleaned bone surface of the other joint member.

Abstract: A piston, backed by a resilient disc, both slidable within a cylindrical case, is provided, on its leading end, with a penetrable conductor pellet, sheathed within an insulator cap. Upon firing of an explosive charge of disc form, arranged behind the piston with a polyethylene disc interposed between the charge and the piston, the latter will be driven forwardly against a pair of piercing points on the ends of a pair of conductor wires mounted in an insulator header in the leading end of the case, the driving force of the explosion being sufficient to cause the conductor wire points to pierce entirely through the insulator cap and to become embedded in the conductor pellet, thus closing a circuit across the conductor wires.

Abstract: A piston, normally contained in a retracted position within a cylinder, is projected by electrical detonation of an explosive charge which is contained within the cylinder between a sealed end thereof and a piston having a circular cutting edge at its end remote from the explosive charge, such remote cutting end being normally held in spaced relation to a wire extending through diametrically opposite openings in the cylinder, by a shock-security pin or equivalent means, of a material of sufficient softness to be readily sheared upon detonation of the charge, allowing the piston to advance into shearing engagement with the wire.