Patent GB-497723-A (GB)
Title: Improvements in mechanical calculators
IPC: G06G3/00
Filed: 1937-03-18
Abstract: 497,723. Calculating - apparatus ; indicating - apparatus. SORDOILLET, P. March 18, 1937, Nos. 7997 and 7998. Void. Convention dates, March 19, 1936 and Feb. 23, 1937. [Classes 106 (i) and 106 (iv)] The invention relates to a device for ascertaining the product or quotient of two variables and more especiallythe total cost of a commodity when the quantity and unit price are known. The device comprises two movable elements in the form of slidable carriages one of which is displaceable in accordance with one variable and through a variable ratio transmission mechanism, displaces the other carriage in accordance with the product. The invention is described as applied to a liquid dispensing apparatus, the lifting of the discharge pipe from its hook 23, Figs. 1, 2 and 3, releases the hook to effect the closure of coupling 20, 21 to connect, the shaft 25 of the pump of the delivery apparatus through gearing 16 ... 19 to a shaft 26 carrying a pinion 15 in mesh with a rack 14 secured to a carriage 9 slidable on a rail 13. The displacement of the carriage is proportional to the quantity of commodity dispensed and its movement is transmitted to a spring controlled pivoted arm 1 by means of a roller 8 on the carriage engaging a rib 7 on the front face of the arm. On the rear face of the arm 1 is a rib 10 on which bears a roller 11 slidably mounted in a slot 28 of a carriage 12 mounted on a rail 42. The adjustment of the roller 11 depends on the price per unit quantity of the commodity and is effected by the operation of a crank 30 which through gearing 33, 34, a sleeve 35, ribbed shaft 37, and gearing 39, 40 drives a screwed spindle carrying the nut 41 supporting the roller 11. The displacement of the carriage 12, in operation, is thus proportional to the total cost of the commodity. The shaft 26 carries a flange with a transparent disc on which the quantity indications are marked, and the rack 43 on the carriage 12 drives a pinion 44 on a spring controlled sleeve on the shaft 26 to which is secured a fiange with a transparent disc 45 marked with amounts representing the total cost. The price per unit quantity is shown on drums 31 set by the crank 30. The markings on the discs are optically projected on to screens covering apertures in the casing by an optical system comprising a lamp 50, reflector 51, condenser 52, prism 53, and lenses 54. After a dispensing operation the filling pipe is placed on its hook 23 which is thereby depressed to disengage the clutch whereupon the spring 3 of the arm 1 and the spring 46 of the sleeve restores the carriages to their initial position as determined by an adjustable stop 57. To prevent re-engagement of the clutch during the resetting operation a spring controlled lever 60 enters into the space between the clutch parts until the carriage at the end of its return movement meets the end 64 of the lever to withdraw it to ineffective position. In place of the optical means for giving the indications, counters with a Geneva-type transfer mechanism may be provided. Means may be provided to stop the delivery mechanism automatically. For this purpose electric contacts may be placed in the paths of movement of the carriages which will be operated to open the motor circuit after a predetermined quantity or total cost has been reached. One embodiment of this mechanism is shown in Figs. 5 and 6, wherein a stop 66 with pairs of contacts 68a, 68b and 69a, 69b is arranged on a screwed spindle 67 between the carriage rails 13 and 42 and adjustable into position by the operation of a crank 72 in dependence on the quantity as exhibited by a counter 74 or the total cost as shown by a counter 76. The contacts 68a, 69a are first acted upon to slow down the motor while the other contacts effect the stoppage. These contacts are arranged in circuit as shown in Fig. 6, the motor 78 is connected to mains 79 through series contacts 80a, 80b of relays 81, 82 so that on the opening of the first pair of contacts 68a, 69a, the relay 82 is de-energized and inserts a resistance 84 in series with the relay 81. When the contacts 68b, 69b are subsequently opened the relay 81 is de-energized to cut off the motor supply.