GB547294A - Improvements in or relating to the folding of workpieces - Google Patents

Abstract

547,294. Coating with adhesives. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). Feb. 20, 1941, No. 2312. [Class 95] [Also in Group VIII] A machine for folding the marginal portions of sheet material, e.g. for folding French binding around the edge of a shoe upper, is provided with means for delivering thermoplastic adhesive in heated condition to the workpiece as it is being operated upon to secure in position the folded portion. Successive edge portions of the workpiece are turned upwardly against a creaser foot 22 by an oscillatory folding finger 20, and the folded portion is pressed against the body portion by a hammer 26 and anvil 28. The work may be clamped against the foot 22 by a gripper member 24 operated as described in Specification 208,217, [Class 42 (i)]. The adhesive is supplied to the work through a passage 156 in the creasing foot 22 from a reservoir 182. The reservoir, the foot 22, and the connections between these parts are heated electrically. The heating of these elements may be varied by adjusting a rheostat, and the temperature of the foot is indicated by a thermometer 411. The adhesive is delivered by a pump 180 arranged within the bottom of the reservoir, and comprising a slidable sleeve 206 and plunger 210. Ports 212 spaced 180 degrees apart are provided in the sleeve 206, one port providing communication from the reservoir to an intake port 214 in a second sleeve and serving as a valve controlling the. flow of adhesive. The sleeve 216 is arranged to be rotated to open and close the port 214 upon energisation of a solenoid 290. A plunger having markings upon it or other device may be provided for indicating whether the port 214 is open or closed. Means are provided for varying the effective stroke of the pump to vary the amount of adhesive delivered to the workpiece. Heat radiating ribs are arranged to extend partly across the reservoir, and a bellow-form thermostat is connected to a bulb 192 arranged below the heating element 188 for the reservoir so as to operate a switch to control the supply of current to the heater. The position of the edge of a workpiece is determined by a gauge finger 30. When folding joints between overlapping ends, or at sharp corners, the workpiece may be manually presented to an adhesive-applying roll supplied with heated adhesive.