GB918023A - Improvements in or relating to shoe upper conforming machines - Google Patents

Abstract

918,023. Shoe upper conforming machines. BRITISH UNITED SHOE MACHINERY CO. Ltd. April 27, 1959 [April 29, 1958], No. 14209/59. Addition to 882,748. Class 17 (1). A toe-lasting machine as claimed in the parent Specification includes a manually-operable lever 54 for advancing and closing the wipers, a control member 202, associated with the lever, which may be actuated by the operator to bring about power effected movements of the wipers, and means for controlling these power effected movements so as to produce a servo-action effect in accordance with movements of the lever, whereby the operator controls the power effected movements as positively as he controls movements by means of the lever alone. Initial movement of the control member brings about power-operated advancing and closing movements of the wipers, and a second movement of the member brings about power-operated height-wise movements of the wipers. The wiper operating linkage from lever 54 includes a lever 70, pivoted at 74 to a block on bleed valve 78, a link 80, and a bell-crank 84. Also connected to bell-crank 84 is the operating-rod 100 of a fluid-pressure actuator device 102, and the rod 110 of an hydraulic control piston 112. When the wipers are operated manually the bleed valve is held against its seating by a lever 160 clamped by the rod of a piston 170, so that pivot 74 is stationary. When member 202 is moved initially it swings lever 200 which moves rod 204 endwise against spring 210, and a cam surface 226 thereon actuates a switch 232 to energize a solenoid 274, not shown. As a result, piston 246 is operated, swinging lever 240 so that valve 132 is drawn against its seat 136, and switch 280 is closed to energize a solenoid 188 (not shown), causing cylinder 174 to be connected to exhaust, whereupon piston 170 is withdrawn from lever 160 which is left to the action of spring 166 only. Now as lever 54 is swung, valve 78 is withdrawn, permitting fluid to flow from one side of piston 112 to the other, and actuator 102 becomes operative to move the wipers. This movement tends to close valve 78 so that a servo action is provided. When plunger 202 is released, rod 204 &c. are returned by spring 210, discontinuing the operation of actuator 102 and opening valve 132, pin 74 once more becoming fixed. Heightwise movement of the wipers may be brought about by means of a treadle 34 acting via link 350, lever 354, and link 360, or by means of a fluid-pressure actuator 372 acting via arm 358 of lever 354. At the initial movement of member 202 rod 204 is moved endwise until flange 406 just engages bushing 400, and the end 391 of the rod just contacts the bottom of a recess 393 in the stem 390 of valve 218. On continued movement of member 202, against the additional resistance of spring 404, rod 204 opens valve 218, and fluid passes to actuator 372. After lasting, a lever 430 on the wiper head is used to operate a valve 422 for supplying fluid to actuator 372 for the bedding-down action, and for relieving this action. Heightwise movement of the wiper head during overwiping is resisted by means of a friction block pressed against link 360 by a cammed lever operated by a piston which is actuated when member 202 is initially operated. This resistance is readily overcome by actuator 372 during the bedding-down action. The jack is of known construction, the movement of the jack pin to clamp the shoe being effected by a fluid-pressure actuator 508 operated by means of a knee pad 596. The return movement of the last pin is resisted by an adjustable, frictionallyheld cam stop. A spring 644 which normally pulls lever 84 to open and retract the wipers is rendered inoperative by a piston which is actuated at the same time as actuator 508. The hydraulic circuit is described and illustrated, and the arrangement is such that actuation of the knee pad 596 at the end of the lasting operation discontinues the bedding action, releases the shoe, and permits spring 644 to retract and open the wipers.