Patent GB-444771-A (GB)
Title: High speed shaping or like machine with hydraulic ram drive
IPC: B23Q5/26
Filed: 1935-01-24
Abstract: 444,771. Hydraulic shaping-machines. LANGE, A., 43, Raffineriestrasse, Halle-on- Saale, Germany. Jan. 24, 1935, No. 2413. Convention date, Jan. 24, 1934. [Class 83 (iii)] [See also Group XXIX] The ram of a high speed shaping or like machine is driven by a hydraulic cylinder 10 supplied by lines 8, 9 from a variable-delivery pump 3 through a reversing valve 12 coacting with a control valve 18 which may be set so that for slow speed roughing work the line 8 to the front of the piston receives pressure fluid while for high speed finishing work both the lines 8, 9 are open to pressure, the control valve having also an intermediate neutral position wherein the supply to ram cylinder is cut off. The pump, drawing from a tank 4, is driven by a motor 1 and the casing 3 of the pump may be oscillated about a horizontal axis to a position a in order progressively to increase the delivery. The pump delivers through the line 6 to a reversing valve 7 carrying a rotary element 12, Fig. 4, which is provided with chambers 16, 17, the chamber 16 being constantly open to the supply line 6. The rotary valve is actuated by fluid pressure supplied by an auxiliary pump 24 driven by gearing 23 from the motor 1. This pump delivers through a line 26 to a piston valve 33 communicating with a semi-annular chamber 29 in the reversing valve body, this chamber being partly filled by a blade 30 on the rotary part 12, Fig. 2. The piston valve is actuated by abutments on the ram so that at the required times, it admits fluid to one end or the other of the space 29 and rotates the valve 12 through 90‹. Lines 34, 35 conduct oil from this system to lubricate the whole machine. The table feed is derived from a shaft 14 slidably journalled in the valve 12. In the position shown in Fig. 1, the shaft 14 is coupled at 40 to rotate with the valve 12, this movement being transmitted through a ratchet clutch 36 and bevel gearing 38 to give an intermittent table feed. The coupling 40 is arranged to give variable lost motion to vary the feed. By a lever 41 the shaft 14 may be moved to the left and coupled with a member 42 driven from the pump 24 to give a continuous table feed. A lever 43 operated by the valve 12 is connected to the casing 3 of the main pump. During the power stroke of the ram, the parts are positioned as shown in Fig. 1 and the pump delivery is controlled by means of a cam 45 engaging the casing. For the return stroke, the movement of the valve 12 lifts the pump casing to the position a to obtain maximum pump delivery and a high speed return. For rough shaping the control valve 18 is positioned as shown in Fig. 4. In this case, for the forward stroke the pump delivery passes from the chamber 16 to the line 8 while the discharge from line 9 passes through the valve 18, passage 19 and chamber 17 to return line 15. For the return stroke the valve is positioned so that the delivery passes into the line 9 while the line 8 is open to return line 15. For smooth shaping the control valve 18 is turned through 90‹ so that on the forward stroke, Fig. 6, both the lines 8, 9 are open to pressure so that the oil behind the piston 11 and also the delivery from the pump both pass through the line 8 to the front of the piston to give an increased speed of operation. For the return movement the valve is turned 90‹ anti-clockwise from the Fig. 6 position so that the line 8 is open to return and the line 9 to pressure. In an intermediate position of the valve 18 a passage 21 open to pressure is uncovered by a bore 22 in the valve so that the delivery from the pump is byepassed back to the tank. Preferably, there is a lost motion connection between the valve 12 and lever 43 so that the pump 3 is not moved to its maximum delivery position until after the return flow through the line 9 has commenced and is moved from said position to reduce the oil flow before the change from reverse to forward movement.