Liquid dispensing apparatus

767,279. Dispensing liquids. STANDARDTOCH CHEMICALS, Inc. Feb. 6, 1954, No. 3540/54. Class 116. Tanks 20, Fig. 2, are moved to position a selected tank to deliver to a container 103 through a positive displacement pump 25 until a selected volume of liquid has been delivered. In the machine illustrated the pumps 20 are arranged in annular form about a hollow shaft 131 by which they are rotated to position the selected tank for delivery. The tanks contain pigments carried by a suitable liquid vehicle to be mixed with white paint in the container 103 and the machine may be set to deliver selected volumes of several selected pigments in succession. The pigments are delivered by gear pumps 25 rotated through pinions 28, 29 from a central shaft 37. When the machine is not in use the containers revolve continuously while the shaft 37 is stationary so that the pumps 25 withdraw liquid from the tanks and return it through two-way valves 32 either to a pipe which returns the liquid above the surface of the liquid in the tanks or to a submerged pipe provided with jets for stirring the liquid. When liquid is to be delivered from a selected tank the shaft 131 is stopped with the selected tank above the container 103. In this position a solenoid 130 common to all the tanks may depress a plunger 136 on the valve 32 so that the pump 25, which is now driven through the gears 28, 29 from the shaft 37, delivers the liquid to a nozzle 148. The nozzle 148 has the section indicated in Fig. 14 to prevent drips when delivery is complete. The delivery is metered by pulses transmitted by switches operated by cams on the shaft 37 and transmitting pulses to counters which terminate delivery when the volume indicated by manually controlled switches associated with them has been delivered. The colours of the pigments to be delivered are set by three manually operated switches 77, 78, 79, Fig. 8, and, when the corresponding quantities have been set on switches associated with the counters 80, 81, 82 and the size of the container 103 has been set on a switch 83 a switch 71 is set to connect A.C. supply to each of two conductors 74, 76 and a selflocking switch 87 is closed. The conductor 74 supplies operating current to the motor 48 which rotates the tanks until a switch 90 is closed by a cam on the shaft 131 to indicate that the tank selected by the switch 77 is in position for delivery. This completes a circuit over a multi-conductor cable 93 and the selected contact of switch 77 and ov