GB619257A - Hydraulic control means for ring rolling machines - Google Patents

Abstract

619,257. Rolling annular bodies. LOEWY ENGINEERING CO., Ltd., and WATSON, J. S. Nov. 28, 1946, No. 35289. [Class 83 (iv)] Hydraulic control means for ring-rolling machines having a fixed outer roll 10 and a movable inner pressure roll 11, comprises forward and return cylinders 14 and 18, for feeding the roll 11, inlet and exhaust valves 24, 25, and 26, 27, for each cylinder respectively, and a controllable throttle valve 33 in the exhaust line of the return cylinder 18, whereby the forward movement which the pressure roll 11 tends to make when beginning to ride over the thinner portion of the work ring B is slowed down to such an extent that the roll 11 will not come into effective contact with the ring, reduction being limited to the thicker part. A compression spring 20 serves to keep the pressure roll 11 in contact with the blank B to ensure that it rotates between the rolls 10 and 11 at all times. The throttle valve 33 may be byepassed by a normally closed valve 34 for rapid forward movement of the roll 11 to approach the work. Valves 36 and 35 respectively prevent air entering the return cylinder 18 and excessive pressure being built up in the forward cylinder 14, in the event of the roll 11 making a receding movement due to the throttle valve 33 being opened too far at any time during the passage of the blank B.