GB1306119A - - Google Patents

Abstract

1306119 Stops HARDINGE BROS Inc 16 April 1970 [17 Dec 1969] 18215/70 Heading B3B Hydraulic apparatus for machine tools, e.g. a turret lathe, for limiting the deflection of a stop 109, 207 at the end of travel of a machine tool part 200, TC, comprises a piston-and-cylinder 201, 206 and 110, TP, a first fluid line 104, 204 connected near one end of said cylinder, a second fluid line 116, 208 connected near the other end of the cylinder, said fluid lines being alternately inlet and exhaust lines in response to the operation of valve means 102, 203 and causing relative movement between said piston and said cylinder, a pressure reducing valve 128, a pump A for introducing fluid into the first or second line acting as an inlet line and into said pressure reducing valve 128 at a first predetermined pressure, e.g. 300 p.s.i., fluid being conveyed through passage means 132, 220 from said pressure reducing valve 128 to said valve means 102, 203 and to the first or second lines acting as an exhaust line at a second predetermined pressure, e.g. 175 p.s.i., substantially above atmosphere, said passage means including a one-way valve means 134, 222 arranged to permit fluid passage from said pressure reducing valve 128 to said valve means 102, 203 and a line acting as an exhaust line but to prevent fluid passage from said valve means 102, 203 to said pressure reducing valve. During normal movements of a slide 200 or a turret TC, choke valves 212, 214 &c. are switched in by solenoid operated valves 216, 218, &c. to control the speed of movement. The main valves 102, 203 are also solenoid-operated.