Patent GB-540021-A (GB)
Title: Improvements in ironing presses
IPC: D06F71/06
Filed: 1940-03-28
Abstract: 540,021. Manually-actuated valves. ALLEY, S. E., GARDNER, C. S., and ALLEY, S. E. March 28, 1940, No. 5591. [Class 135] [Also in Group VIH ] In an ironing press wherein the movable buck or head is operated by fluid pressure, on both the pressing stroke and the return stroke, acting through a piston, toggle links and lever, the piston operates in a cylinder formed with brackets secured to and bracing side cheeks of the press frame. The piston is formed with two heads of different diameters working in a two diameter cylinder and the pressure fluid acts on the large diameter of the piston to effect the pressure stroke and on an annular area of the piston to effect the return stroke. Control is effected by a valve requiring both hands of the operator to actuate the press. The press frame is constructed with side cheeks 18, Fig. 2, and front and rear removable plates 15, 16 and is braced by a twodiameter cylinder 27 in which operates a piston 32 with trunk 33 connected by a rod 36 to toggle links 39, 47, the power link 47 being pivoted to the frame by a tube 52 or pin and to the upper link 39 which is pivoted to the cheeks of the arm 24 carrying the movable head 23. The press is operated by compressed air supplied by a pipe 53 and a control valve, and the pipe 53 has a branch in constant communication with the annular space behind the piston 32 through a spring controlled valve 60, Fig. 6, and port 57 leading to that space : the spring yields to increase the valve area when fluid is passing to effect opening of the press. Thus when the control valve cuts off pressure from the front end of the cylinder 27 and opens it to exhaust through a pipe 55 and a silencer, the pressure in the annular space returns the piston and raises the head, but when pressure is directed to the front part of the cylinder air is forced from the annular space into the pressure supply pipe 53 and cushions the pressure stroke, the cushioning being regulated by a manually adjustable pin 58 whose point enters more or less into an aperture 62 through the valve 60. The cylinder 27 and the pivots 52 and 48 act as struts or braces between the cheeks of the frame. The control valve, which is the subject of Specification 548,952, comprises a casing 54, Fig. 8, housing a sleeve 69 forming seatings for a ball valve 70 and for a valve 74 which is pressed down by a spring 79 from a slidable stem 73 having a head 81 operated by finger levers 89, 90 arranged under a guard hood 98. The stem movement is limited by a pin 80. In the position shown the pipe 55 leading from the cylinder is in communication through the valve 74 with a passage 77 to a silencer and exhaust and the piston can be returned and the head lifted by compressed air led by the branch from the pipe 53 to the annular space behind the piston. When, however, the stem 73 is depressed by the action of both hands on the finger levers 89, 90 the valve 74 is closed and a projection 75 thereon depresses the ball valve 70 to connect the pressure supply pipe 53 with the pipe 55 leading to the cylinder. This position is maintained by a spring-controlled locking spindle 100 engaging a groove in the stem until released by a finger lever on the spindle.