Patent GB-849119-A (GB)
Title: Improvements in automatic zero resetting devices for indicators or the like
Inventor: CARRIOL LOUIS AUGUSTE
IPC: G06M1/28
Filed: 1957-09-09
Abstract: 849,119. Liquid dispensing apparatus. SOC. D'ETUDES D'INVENTIONS ET DE BREVETS S.E.I.B. Sept. 9, 1957, No. 28425/57. Class 116 [Also in Groups XIX and XXIX] In a numeral wheel indicator for liquid dispensing apparatus there is provided zeroizing mechanism of the kind in which pawls on the numeral wheels cooperate with a grooved shaft, the grooved shaft being rotated idly in a direction corresponding to the decreasing order of digits on the wheels and being then caused to perform an operative rotation in the opposite direction to zeroize the wheels, the idle rotation being effected by the pressure of liquid delivered by the pump of the apparatus. A spring is stressed during the idle rotation, the energy stored thereby effecting the operative rotation. As applied to liquid-dispensing apparatus having four sets of numeral wheels and transfer mechanism, Fig. 1, liquid delivered by a pump 62 passes through a separator 63, meter 64, valve 66 (see Group XXIX) and distributing pipe 67, the rotational movements of the zeroizing shaft being controlled by liquid pressure in a cylinder-and-piston unit. A shaft 3, Fig. 3, is driven through bevel gearing from the meter 64 and rotates a pinion 43 via a unidirectional clutch. A cylinder 25 contains a piston 24 whose movements are controlled by a slide valve 26, Fig. 8, the piston 24 carrying a rack 23 which rotates a pinion 20 on a shaft 19. The slide valve 26 controls a rod 31, Figs. 3 and 4, which controls a lever 32 secured to a shaft 33 to which is attached a lever 36 whose end bears against a cam 21. Rotation of the pinion 20 causes rotation of a pinion 21f secured to the cam 21 and rotation of the shaft 19 causes rotation of a shaft 104, Fig. 3 through a crank 105 and hence tensioning of a spiral spring 22. A fork brake 111 subject to the action of a spring (not shown) is disengaged from a grooved wheel 113 when the lever 36 drops into the recess 21e in the cam 21. The transfer shafts 121a-121d are controlled by a cam 120, Fig. 5 operated by a crank 122 and co-operating projection 120a, and are normally held with the transfer pinions engaged, by a spring 123. In operation, unhooking of the nozzle 68 starts the pump 62 and liquid flows through the duct 27 into the cylinder of the slide valve 26 which moves slightly to the right so that the pump pressure is transmitted by the duct 29 and forces the piston 24 to the right thereby rotating the pinion 20 and shaft 19 through 440 degrees in the direction of the arrow and hence driving the cam 21 by 350 degrees. The 440 degrees rotation of the shaft 19 tensions the spring 22, disengages the transfer shafts 121a-121d from the cam 120 and rotates the crank 105 and hence the member 108 so that the numeral wheel shafts 109a-109d are rotated by 440 degrees in an ineffective direction, the grooves of the shafts 109a-109d being brought to a position where the wheels can be picked up with minimum error. Zeroizing. When the shaft 19 has rotated by 440 degrees, the lever 36 drops into the recess 21c thereby moving the slide valve 26 to the right. This connects together the ducts 28, 29 so that the cylinder 25 communicates with the drainage vessel 65 at atmospheric pressure to allow the piston 24 to move to the left. The shaft 19 now rotates under the action of the spring 22 which was tensioned previously. The shafts 109a-109d are rotated in the direction of increasing numerals borne by the numeral wheels to pick up pawls on the wheels, returning them to zero. Just before the piston 24 reaches the cylinder head 25a the crank pin 122 abuts the projection 120a moving the cam 120 to lock the transfer pinions in position. When the head 25a is reached, the lever 36 drops into the recess 21 to shift the valve 26 further to the right to connect the ducts 27, 30 and open the valve 66 by liquid pressure. The shaft 33 is also rotated to disengage the brake 111. Termination of delivery. During delivery the numeral wheels are driven from the input shaft (not shown) by the gears 118. When the nozzle 68 is hooked up, the pump stops and the slide valve is returned by a spring. The lever 36 hence moves anticlockwise and rides up to the periphery of the cam 21 and the shaft 33 is rotated to bring the brake 111 into operation. The apparatus which has two sets of numeral wheels for quantity.and price, may have a lowest order price wheel with alternate zeros and fives, Fig. 13. The right hand face 7a of this drum is provided with an oscillatable pawl 130 and associated spring 131 which replace the pawl cooperating with the groove in the shaft. The pawl 130 cooperates with a recessed disc 132 bearing a pin 132b disposed in the path of a sector 133 secured to the shaft so that when the shaft rotates in the direction of decreasing digits the sector 133 abuts the pin 132b and the pawl 130 jumps over the recesses in the disc 132, and when the shaft is oppositely rotated the sector 133 first rotates freely and then abuts the pin 132b to drive the disc 132 and numeral drum 7a to zero without affecting the drum of next higher denomination. Specification 833,061 is referred to.