Patent GB-710277-A (GB)
Title: Method of and apparatus for dividing by volume plastic substances
IPC: A01J21/02
Filed: 1951-08-30
Abstract: 710,277. Delivering measured quantities of liquids. LEVER BROS. & UNILEVER, Ltd. Aug. 30, 1951 [Sept. 1, 1950], No. 20461/51. Class 106(5) [Also in Groups V and XXVIII] A method of dividing by volume liquid or plastic substances comprises rotating a cylinder 10 in a casing 5 having an inlet 6 connected to a source of the substance and an outlet 7, the cylinder having a channel 11 and a plunger 12 slidable in the channel, to bring the open end of the channel into line with the inlet, moving the plunger in the channel through a stroke length to permit the substance to enter the channel through the inlet, rotating the cylinder to bring the open end of the channel into line with the outlet moving the plunger through the same stroke length to eject the substance from the channel into the outlet, forming the substance ejected by the plunger into a continuous bar and cutting the bar by a device 37 once after every ejection stroke of the plunger, the stroke of the plunger being adjustable so that the plunger can reach the 'surface of the cylinder only, if at all, when the stroke is adjusted for maximum length and cannot reach the surface when the stroke is adjusted for less than its maximum length. The cylinder 10 is rotated by a shaft 13 driven through bevel gears 14, 15 and a Geneva mechanism (not shown), whereby the cylinder 10. is at rest while the plunger 12 is moved. Plastic substances may be forced into the channel 11, when in line with the inlet 6, by a 'screw 9, the rotation of which may be synchronized with the rotation of the cylinder. The stroke of the plunger 12 is limited by the internal diameter of a drum 19, through a peg 16 on the plunger protruding through a slot in the cylinder 10 and carrying a conical roller 17 which engages the internal surface of the drum, this having the same taper as the roller. Owing to the taper on the roller and drum surface the stroke of the plunger may be adjusted by moving the drum 19 perpendicularly to the stroke which may be accomplished by a screw operated by a hand-wheel 21. The plunger 12 may be pushed from the inlet to the outlet end of the channel 11 by the pressure of the material forced in, e.g. by the screw 9, ejecting the material which was left on the outlet side of the plunger after the previous half revolution of the cylinder 10. Provision for moving the plunger mechanically is shown in Fig. 3 where a cam, not shown, rotates a spindle 25, through an arm 23, and so moves an arm 26 also fixed to the spindle. An L-shaped lever 27 is freely rotatable on the spindle 25 and is connected to a lever 31 by a peg 34 which works in slots 30, 32 in the ends of the levers. The lever 31 is pivoted to the casing 5 at 33 and its other end is in contact with the peg 16 on the plunger 12. The movement of the arm 26 is imparted to the lever 27 through a 'spring 28, -adjustable by a screw 29, which takes up any movement of the cam follower 23 occurring after the peg 16 has come into contact with the internal surface of the drum 19. The outlet pipe 8, which may have a different cross-section from that of the channel 11, as required for the crosssection desired for the divided substance, is just shorter than twice the plunger stroke to ensure that the joint between two successively extended blocks of substance is not cut. The cutting device 37 may be actuated by a cam driven from the main shaft.