Patent GB-841235-A (GB)
Title: Improvements in or relating to paint-dispensing machines
IPC: G05D11/00
Filed: 1959-02-18
Abstract: 841,235. Mixing paints. BERGER & SONS Ltd., L. Feb. 18, 1959 [June 9, 1958], No. 5672/59. Class 86 [Also in Group XXXVIII] A paint-formulating machine 'comprises a number of liquid reservoirs, a positive displacement pump for each reservoir capable of delivering the liquid to a dispensing point common to all the reservoirs and pumps, and means responsive to numerical intelligence fed into the machine for selecting the reservoirs to be connected to the dispensing point, and the quantity of liquid from each reservoir, according to the required nature of the mixture. In the machine described, provision is made for selecting liquids in predetermined quantities from any three out of eight reservoirs 31-38, but greater numbers of reservoirs and selections therefrom could be employed. The selection of reservoirs, and the quantity from each, may be made by setting controls manually, or by inserting a punched card into the control panel 95 at 100, in both cases electric circuits being activated to connect the selected reservoirs by pipes 61-68 to the dispensing point. The punchedcard control box 94 may be interchanged, through a multiple contact disconnecting plug, with a manually preset control box, the circuitry being substantially the same in both cases. The nozzles 51a-58a are carried by a plate 39 above the final container which is removably supported on a plate 41 supported, cantilever-wise, at different levels, according to the size of the container, on pins 42, 43, 44 projecting from a column 40 which carries also the plate 39. The nozzle orifices are small to prevent drip when the pumps stop. Each reservoir 31-38 and its pump 71-78, preferably a gear pump, is a replaceable unit comprising a base 165, casing and cover 81, shaft and agitators 170, 171, 172 and pump suction 185. When a unit is positioned, a clutch pin 175 engages drive pins on a shaft 180, and the pump shaft 191, Fig. 8, is presented to a clutch 195 on a shaft 197. All the shafts 180, 197, as well as a shaft on an electric-pulse generating and counting means, are sprocketed to be driven by a common chain, the clutches 195 being selectively energized to drive selected pumps in accordance with data fed to the machine manually or by punched card. The clutches each comprise a spring 204 surrounding the abutting ends of the shaft 197 and a sleeve 221 coupled to the pump shaft 191 at 211. The spring 204 is secured at 203 to the hub 220 of a disc 210 having four projections 215 any one of which may abut against a solenoidactuated stop 212 to prevent rotation of the disc and thus to loosen the spring 204 on the said abutting ends. When, as determined by the said data, a particular solenoid is energized, the associated disc 210 is released, and the clutch becomes operative to drive the selected pump. The pulse-generating and counting means has a disc, similar to the disc 210, which is released by a solenoid-actuated stop, four cams on the face of the disc closing a micro-switch four times per revolution, so that quarter revolutions of the gear pump, and thus the quantity delivered, are counted. The quantities of liquids supplied by the pumps are controlled by stepping- switches which are set either manually by dials graduated in units, tens, hundreds and thousands, or by the punched card, so that -a particular pump stops when its stepping switch has received the required numbers of pulses. Similarly, the selection of pumps is made either manually by dials, each of which is set to excite the solenoid of a chosen pump; or by the punched card which likewise renders the clutches operative. The placing of a container in position to receive the liquids closes a master switch, a starter button then being momentarily pressed to close the contacts of a starter relay which activates a time delay relay and the pulsegenerator, the time delay relay activating the pump solenoids. The punched card is inserted between a fixed lower contactcarrying plate and a top plate, carrying spring-finger contacts, which is raisable by the handle 101. One zone only of the card is used, according to the magnitude of the quantities to be dispensed, and to permit this, the card is movable by a rack and pinion operated by the knob 102 to bring the required zone under the spring contacts. A master perforation, one for each zone, allows, when the card is correctly positioned, contacts to close; and when further contacts are closed by depressing the handle 101, the card reader is activated. When a dispensing operation is complete, a homing circuit resets the apparatus for a further operation.