GB648700A - Improvements in or relating to fluid motors - Google Patents

Abstract

648,700. Pneumatic single-stroke apparatus. AKTIEBOLAGET SVENSKA KULLAGERFABRIKEN. Oct. 17, 1947, No. 27899. Convention date, Oct. 3, 1945. [Class 8(ii)] [Also in Groups XXVI and XXIX] In a pneumatic apparatus comprising a cylinder 2, a piston 4 reciprocable therein, a source of pressure gas in continuous communication with one end 24 of the cylinder and the corresponding face of the piston and valve means actuated by the piston to reverse the direction of and to adjust the length of strokes of the piston (see also Group XXVI), a single upward or downward stroke of the piston is effected by mechanically stopping the piston at the end of its stroke by the valve actuating means 5 and 6, operatively connected to the piston rod 28, contacting stop pins 16 and 17 respectively attached to the cylinder. In the position shown the pressure gas is supplied through a connection 22 and a passage 23 to the cylinder space 24 above the piston, to a valve chamber 25, and to the cylinder space 21 above the piston through a needle valve 19 a chamber 26 and a passage 27. Due to the differential areas of the piston 4 it moves up until the collar 6 contacts the pin 17. To reverse, a handle 45 is depressed and a lower fork arm 13 lifts a valve 11 which allows pressure gas to pass to a space 31 behind a piston valve 7 and move it to the right thereby opening the space 21 below the piston to atmosphere via a needle valve 20; the piston then moves down until the collar 5 contacts the pin 16. To re-position the apparatus for another upward stroke the handle 45 is lifted thereby opening a valve 10 by means of an upper fork arm 12 and allowing pressure gas to pass to a space 38 behind the other end of the piston valve 7 and return it to its original position. The length of the upward stroke of the piston may be varied by adjusting the collar 6 axially on the rod 42. The piston valve is magnetically maintained in its extreme positions, the spaces 31 and 38 between it and its cylinder ends being normally open to atmosphere through passages 30, 37 and ports 32, 39 in valves 10 and 11 respectively.