Patent GB-523664-A (GB)
Title: Improvements in or relating to machines organized for applying pressure and heat to bottom portions of shoes
IPC: A43D47/00
Filed: 1938-12-10
Abstract: 523,664. Machines for pressing shoe-bottoms. BRITISH UNITED SHOE MACHINERY CO., Ltd. (United Shoe Machinery Corporation). Dec. 10, 1938, No. 36035. [Class 17 (i)] A machine for applying pressure and heat to the margins of uppers on the bottoms of lasted shoes before outsoles are placed on the shoes, has independent devices for engaging the forepart, shank and heel end; and means for adjusting these relatively, for style of shoe. The devices are first moved heightwise to press against the shoe bottom, and then inwardly across the shoe bottom to perform an ironing operation thereon. Resilient metal plates bed themselves against the shoe bottom and are supported by means which progressively increase the pressure of the plates against the shoe bottom during the ironing operation. The ironing devices are moved upwards by fluidpressure. The machine is provided with twin work stations, and means are provided for limiting the time during which a work-piece is under pressure. After work-positioning, the rise of the ironing plates is initiated by depression of a treadle admitting fluid to the cylinder of the station just loaded, depression of the treadle releasing the pressure in the cylinder of the other station. In addition, a timing device ensures that should another workpiece not be positioned, pressure in the machine is released after a predetermined time. The last is supported by toe and heel abutments 42, 44, Fig. 21, against the thrust of the ironing devices, these comprising a metal plate 134, at each side of the fore-part, slotted at right angles to the edge of the last to provide flexible tongues resting on a stouter plate 136, this being supported by ribs 148, 150, respectively, outside and inside the sole area. Electric heaters 354 warm the ironing, plates. The fore-part unit is supported on a pivot 118 and adjusted about this pivot by a screw 258 provided with a handwheel. The plates at the heel seat portion are similar to those at the fore-part, and have an abutment 172: under them. They are adjustable vertically by a hand-wheel on a screw supporting a pivot 305. At fore-part and heel end a plate closes the gap between the side plates at the ends of the shoe. The shank ironers comprise stout springs 216 bent on themselves and provided with abutment blocks 240. The three ironing members on each side of the shoe are pivoted together, and the shank member engages the others by abutment surfaces 210, 212 curved about these pivots. The ironing members are carried by a slide 96, Fig. 18, guided on upright columns 30 and supported by a stout spring 98 from a slide 94 itself adapted to be raised by a piston in a cylinder 362. The ironing devices at each side of the shoe are carried by slides 322 moved inwards by bell-crank levers 332 actuated by links 336 when, as a result of pressure on the shoe, the slides 94, 96 approach each other. To supply fluid under pressure to the cylinders 362, a constantly running pump 416, Fig. 14, draws oil from a reservoir 420 and delivers it to the casing of a valve 434 normally urged by a spring to the right where a port is uncovered allowing the oil to return to the inlet side of the pump. When work has been positioned, the treadle 502, Fig. 3, of the side of the machine concerned is depressed, an arm 516 being thus moved to the left to swing a lever 484 to the left, the lever engaging the head of the valve 434 and also moving the valve 452 of the side of the machine concerned, this being linked to the lever 484, which is urged to the right by a spring 498. With the valves in this position oil passes to the cylinder 362 to lift the slides 94 and 96 and iron the margins of the upper. When a predetermined pressure has been reached therein, fluid passes by a pressureregulating valve 544 to a pipe 548, Fig. 14, supplying a valve linked to a lever 570 linked to the arm 516, which arm, as it is lowered, releases the arm 484 to the pull of its spring and allows the valve 434 to return to normal position and the valve 452 to mid-position, a step on the valve contacting with a bar 584, Fig. 3, carried by a pair of levers 588, one for each cylinder, linked to a lever 595, Fig. 6, normally resting against a stop 605. On the pivot of the lever 595 is a retaining pawl 682 for a ratchet wheel 618 co-operating with a constantly reciprocating pawl 624. The ratchet wheel is urged anticlockwise by a weight 668 and is bored with a plurality of holes to receive a pin 672 carried by an arm 670 arranged, as the wheel is driven clockwise to contact with the lever 600 which itself carries a lug 1686 overlying the pawl 682. The weight 668 is suspended by a chain passing over a drum secured to an arm 658 carrying a pin 660 co-operating with an arm 652 adjustable by a handle 688. This mechanism is so arranged that the shoe is held under pressure for a time taken by the ratchet wheel to revolve from the position wherein the pin 660 has been moved by the weight 668 into contact with the upper edge of the arm 652 to the position wherein the arm 670 comes into contact with the arm 600. When this occurs the lever 588 releases the valve 452, which moves to its exhaust position. Each of the valves 452 carries a roll co-operating with the bar 584, so that as each treadle is depressed to raise the piston in its cylinder, the valve of the other cylinder is moved to the exhaust position. In the pipe leading to each cylinder is a valve comprising a ball 714, Fig. 14, co-operating with upper and lower seatings, the upper seating leading to the cylinder being castellated, and the lower being bye-passed by a small adjustable passage to prevent sudden release of pressure in the cylinder. A pin 704 upheld by a spring housed in a piston in line with a pin, holds the valve in its higher position when the piston is not depressed by pressure of fluid in the cylinder. To release work quickly when desired, a treadle 740, Fig. 3, actuates both levers 484 to move the valves to discharge position. A connection from the treadle raises the pistons of the valves 714 so that a cylinder under pressure may empty quickly. Specification 467,583 is referred to.