Patent GB-668573-A (GB)
Title: Improvements in or relating to shoe bottom pressing apparatus
IPC: A43D25/06
Filed: 1949-09-24
Abstract: 668,573. Shoe bottom presses. BRITISH UNITED SHOE MACHINERY CO., Ltd., and CHOICE, F. C. Sept. 25, 1950 [Sept. 24, 1949], No. 24573/49. Class 17 (i). A shoe bottom press suitable for repairers' use is operated by manual effort of the operator and has operator-actuated means for pressing together the bottom of a shoe and the pressing pad. This latter is filled with fluid, preferably water, at atmospheric pressure and is in communication, through an adjustable pressure-relief valve, with a reservoir. Shoes are pressed successively against the pad with sufficient force to develop pressure in the pad sufficient to open the valve to allow water to flow, and thus reduce the pressure to a pre-determined value which is approximately constant. If the shape of the shoe is such as to require it to be deeply embedded into the pad diaphragm, to ensure contact therewith over the whole surface, the setting of the relief valve is adjusted accordingly. At the end of the pressing operation, spring-operated toggle linkage between upper and lower walls of the pad distends the same to draw back water which has been expelled to the reservoir. Means are provided to permit readjustment of the position of the shoe on the pad, if the distribution of pressure over the shoe requires it, and the shoe is then locked in position. The relief valve may be tripped by the operator to open pad to reservoir and relieve pressure to cause a pivoted yoke which supports a work engaging abutment to rise to permit removal of shoe at end of operation. The shoe is supported on a last L, preferably of the kind described in U.S.A. Specification 2,126,941, and is located with the sole on a diaphragm 21, which forms the upper wall of a pressure pad, approximately centrally of a pressure distributing yoke 101, the pad being adjustable by engaging a suitable pair of notches 47 on ribs on the underside of the pad with wedge shaped edges 17 on a hollow metallic frame which supports the pressure-applying mechanism to ensure pressure being applied to the whole of the sole. The pad comprises a receptacle 19 of which the diaphragm 21 forms the upper wall, and an open reservoir 53 is in communication with the receptacle through a pressure relief-valve 57 operated by a rod 77 lower end of which is connected to a plate lever 87 in a cam slot 89 in which is a cam roll 91 carried by a trip lever 95 pivoted on pin 97 to the main frame. A trip rod 99 convenient to hand of operator is connected to pivot pin of roll 91. The last is held in adjusted position by engagement of an abutment 106 (not shown), carried on a slidable shaft 103 in a handle member 105 of the yoke 101 in a notch on the overhanging part of the last. The shaft 103 may be locked against movement by a locking bar 115 urged upwardly by a spring 126 (not shown), an extension 127 on the bar being adjustably connected to rod 129 pivoted at lower end to lever 131 pivoted on pin 133 on block attached to a link 139 pivoted to one limb of yoke 101. When the yoke is in its upper position and no pressure is applied the,arrangement is such that bar 115 is horizontal but when yoke moves down to apply pressure the locking bar is free to tilt and locks shaft 103 against upward movement. Links 139, 141 pivoted at upper ends on pins 143 to the arms of the yoke 101 control the heightwise position of the yoke, and a spring 146 braces the yoke rearwards of the frame. Pins 143 carry cam rolls 145 which engage inclined coaxial slots in lugs 11 of the frame. In the event of a shoe not bearing evenly against the pad the yoke 101 may be rocked by the operator about its pivot to move the point of engagement of the presser plate with the last and also about the pins 143 to cause the shoe to be tilted on the diaphragm 21 to an extent sufficient to sink all parts of shoe bottom within the diaphragm to the same extent. With the shoe in adjusted position, the operator moves a hand lever 179 forwards to raise rearward end of a pressure locking lever 153 via link 161 to move links 139, 141 downwards to urge shoe against pad. Downward movement of yoke 101 moves an extension 135 of the lever 131 out of engagement with abutment 137 to allow shaft 103 to be locked against upward pressure by the diaphragm 21. The valve 57 opens automatically when water pressure in the receptacle 19 exceeds atmospheric pressure to allow water to escape to reduce the pressure in the receptacle to atmospheric pressure and thus ensures uniformity of pressure for all shoes and guards against damage to the diaphragm. When the pressure has been applied for the requisite period, the operator pushes the trip rod 99 rearwardly to open the valve 57 and disengage pawl 165 from a locking quadrant 163 to release yoke 101 for upward movement away from shoe a short time interval after the opening of the valve so that pressure in the receptacle 19 will have fallen considerably before the yoke is free to rise. A spring finger 171 guards against the yoke being forcibly jerked upwards on release of the pawl. An electrical heating element 187 under control of a regulating switch 189 is placed in a cavity 185 in the base of receptacle 19 to heat the water.