GB1233298A - - Google Patents

Abstract

1,233,298. Sealing metal straps. SIGNODE CORP. 30 Sept., 1969 [10 Dec., 1968], No. 47981/69. Heading B6P. In a trigger-actuated pneumatic tool for crimping a metal seal around the overlapping portions of a metal strapping, the full crimping depth is assured by a pneumatic control arrangement whereby the crimping jaws will not release the seal until the latter has been fully crimped. When trigger 32 is actuated to move valve body 21 downwards against the bias of spring 118, a latch 152 is pivoted by spring 158 about fixed shaft 132 to retain the valve body 21 in its depressed position. Highpressure air is consequently supplied via duct 100 to the rear of piston 44, thereby advancing the piston against the bias of spring 96 to operate the crimping jaws 16. The seal being applied is fully crimped when the piston 44 completes a full stroke. In so doing, the piston 44 contacts an abutment 154 of the latch 152, thereby pivoting the latch to release the valve body 21 which returns to its initial position, in which the rear of the piston 44 is bled to atmosphere. A lever 156 provided on the latch enables the valve body to be manually released. Of the two latching shoulders 160 and 162 provided on the latch, the first 162 retains the valve body in its fully depressed position, and the second 160 retains the valve body once it has moved only part way to its fully depressed position.