Drucksteuervorrichtung

• Main Author: L. HOFFMANN,BERNARD
• Format: Patent
• Language: German
• Published: 25.09.1969
• Subjects: BLASTING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; HEATING; HYDRAULICS OR PNEUMATICS IN GENERAL; LIGHTING; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PRESSES; PRESSES IN GENERAL; PUNCHING METAL; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; TRANSPORTING; WEAPONS; WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS ORPROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL

1,153,562. Hydraulic,pneumatic apparatus. FREDERICK A KRAUSE ASSOCIATES Inc. Sept. 23, 1966 [Sept. 28, 1965], No.42548/66. Heading F1P. [Also in Division G3] A control unit has a housing in which an opening 78 between a reservoir chamber 36 and a chamber 38 in communication with a hydraulic line 42 is provided with a valve 62 biased by a spring 86 to the closed position and responsive solely to the static pressure on one side of the opening for opening movement against the biasing means while a further opening 44 is closed by a check valve 56. The line 42 supplies the pistons of a die punch press and receives fluid through the check valve 56 which is lightly loaded when the pressure in the chamber 38 communicating with the line falls below a predetermined value. When the pistons of the press are retracted, the consequential increase in pressure in the line 42 acts through passages 92 which eliminate the effect of transient changes on a space 70 within the valve to open the latter and place the line 42 in communication with the reservoir through a plurality of semi-cylindrical cutouts 78. The latter prevent surging or foaming of the fluid-flow and may be replaced by segmentally tapered curves formed by grinding the edge of the valve at selected locations. Fluid in the space 70 escapes through a stepped bore which also helps to eliminate transient effects, and an orifice insert 76, to an adjustably-loaded valve 100 communicating through a passageway (not shown) with the chamber 36. An adjustably-loaded safety valve 118 is also provided between the chamber 38 and the reservoir chamber which is provided with a sight glass 28, a helical coil 124 for the circulation of coolant, a fluid supply nozzle 30, and an air line 34 for maintaining the pressure at 100-125 p. s. i. The pressure in the line 42 may be set by the valve 100 at 4500 p.s. i. and is indicated on a gauge (not shown) while the valve 118 is set to lift at 5000 p.s.i.