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 which, when ignited, develops a pressurized gas that is directed, through a transfer tube, into a chamber extending through the piston and into the piston shaft, from which it is directed outwardly through a port in the shaft into a sealed space behind the piston, to move the piston in a direction to exert a pull upon the shaft and a pull-actuated device connected thereto. The piston slidably receives the transfer tube and is sealed thereto to prevent short-circuit escape of the pressurized gas to the leading side of the piston. An electric circuit is provided for igniting the explosive charge when energized.

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.