Improvements in or relating to machines for forming and wrapping shaped blocks of margarine, butter or like plastic substances

摘要

759,643. Moulding butter &c. FORGROVE MACHINERY CO., Ltd. March 10, 1955 . [March 24, 1954], No. 8614/54. Class 87(2) A machine for feeding butter, &c. from a producing machine through pipes 11, 13 and an extrusion chamber 10 to either a single, stationary die as described in Specification 565,143 or dies mounted on a rotary conveyer, from which die or dies the butter is fed by a piston to a wrapping device has a tubular compensating piston 15 which is moved forwardly during filling of a die by a rack 23 and toothed segment 22 and is moved rearwardly by the pressure of the butter, when the outlet of the extrusion chamber is closed, to increase the volume of the pipes and uncover an escape slot 26. The forward ends of the piston and the tube 11 (on which it slides) are bevelled at 16 and 17 respectively to assist in the smooth flow of butter. A shoulder 29 stops the rearward movement of the piston. When a die arrives at the filling position a cam 48, Fig. 4, causes-an adjustable screw 50 to press a lever 38 against a plunger 37 which causes the driving plates 31 to engage the driven plates 35 of a slipping clutch, thus driving a pinion 24 which drives the piston forwardly. The clutch pressure applied is controlled by adjustable springs 42 working against a solenoid 44, and it is arranged that maximum clutch pressure is reached towards the end of the die filling period. When the solenoid is de-energized, the springs 42 cannot exert any pressure on the clutch. A spring 49 holds the cam follower 47 in contact with the cam or in a modification the spring may act against the lever 38 to give instantaneous release of the clutch, when the solenoid is de-energized. In another modification, the solenoid may be dispensed with, the springs 42 acting directly to the lever 38. To give better control of the movement of the piston 15, the clutch may be driven by a cam-oscillated gear segment or uni-directional variable speed drive. Control switches may be operated by the piston to adjust the relative speeds of the producing and forming machines. A stop switch is actuated, when the piston 15 reaches its forward limit, to stop the wrapping machine, to prevent short weights from being delivered due to the fact that piston cannot make a sufficient forward stroke. Specifications 590,935 and 737,052 [Group XXX] also are referred to.