GB745249A - Apparatus for proportioning materials - Google Patents

Abstract

745,249. Delivering materials in proportionate quantities. PROPORTIONEERS, Inc. July 27, 1953, No. 20796/53. Class 86. An apparatus for delivering a plurality of different materials in predetermined proportions comprises a master controller having a synchronous electric generator 15 driven by a motor 10 through an adjustable speed control 12, and a plurality of different stations each for delivering a particular material or combination of materials, each station including a synchronous electric motor 16 connected to the generator 15 by a circuit 17a, the shaft 17 of each motor 16 being coupled to a speed control 18 having an output shaft 19. Each station includes material delivery apparatus and a differential unit connected to the delivery apparatus and to the shaft 19, whereby to maintain the output of the material delivery apparatus constant for any given speed of rotation of the shaft 19 and thereby maintain the total delivery rate and the proportions constant, for any given settings of the controllers 12 and 18. In station No. 1, an electric motor 34 drives two pumps having predetermined piston displacements by the operation of which fluids are delivered from supplies 26, 27 to a reaction vessel 33. The motor 34 has a flexible shaft 35 connected to a differential mechanism 36 and any variation between the speeds of the shafts 19 and 35 causes an electronic speed control unit 102 to adjust the speed of the motor 34 to that of the shaft 19. In station No. 2 a pump 40 delivers a fluid into the reaction vessel through a flow meter 41 and a valve 43. The meter 41 is connected by a flexible shaft 44 with the differential mechanism 45. A by-pass 47 having a valve 48 is provided. Any variation between the meter speed and the speed of the shaft 19 causes the controller 45<SP>1</SP> to alter the settings of the valves 43 and 48 to equalize the speeds. In station No. 3 a tank 62 containing fluid which is to be supplied to the reaction vessel 33 is supported by a pivoted beam 60 and is balanced against a counterweight 65 which is caused to travel along the beam by rotation of a threaded shaft 66 rotatably driven by the shaft 19. A pneumatic controller 71 associated with the beam 60, serves to close or open an outlet valve 64 for the tank 62 when the beam tilts as a result of the loss-in-weight of the tank being greater or less respectively than the loss-in-weight determined by the travelling counterweight 65. In station No. 4 dry material is fed from a hopper 85 on to a conveyer 89 and into the reaction vessel 33, the output of the material being controlled in a similar manner to that in station No. 3. In stations Nos. 1 and 2, any variation in the material delivered beyond a preset tolerance causes a switch to be thrown to stop the whole apparatus. The invention claimed is not restricted to the use of a synchronous electric coupling as described but includes the use of any self-synchronous rotational transmission system having a master unit and one or more slave units which follow synchronously the rotation of the master unit, the system not involving direct mechanical coupling of these units and being largely independent of the location of such units in space, at least within reasonable limits.