Patent GB-426266-A (GB)
Title: Improvements relating to indicating mechanism for liquid measuring and dispensing apparatus
IPC: G01F11/00
Filed: 1933-09-23
Abstract: 426,266. Petrol &c. pumps. AVERYHARDOLL, Ltd., and FRASER, J., Avery House, Clerkenwell Green, London. Sept. 23, 1933, No. 26264. [Class 116] [See also Group XIX] In meter pumps for measuring and dispensing petrol &c., means are provided for automatically zeroizing the indicating mechanism on actuating a member to start the pump driving - motor. The fractions pointers are mounted directly on a shaft 15, which is normally driven during delivery by frictional engagement between a disc 16 on the shaft and a wheel 13 driven through gearing by the spindle of the flow meter (not shown). The units pointers are mounted on sleeves driven by wheels 41, gearing 38, 34 and frictionallyengaging wheels 33, 29 from a sleeve 30 driven by a worm 9 on the flow meter spindle. The wheels 13, 16 and 29, 33 are held in driving engagement during delivery by the thrust of a quadrant 19, Fig. 1, gearing with a sleeve 17 on the shaft 15, the quadrant being influenced by a spring 25 and being provided with a dashpot control 22, 23, 24. On starting a delivery operation, by actuation of a handle as described below, a sector 27 is rotated, thereby rotating a wheel 17<c> on the sleeve 17 and thus advancing the sleeve axially. The axial movement of the sleeve brings a friction disc 17<a> on the sleeve into engagement with a disc 15<a> on the shaft 15 which is moved axially for a short distance thus disengaging the wheels 13, 16 and 29, 33 so that, on further movement of the sector 27, the rotation of the shaft 15 zeroizes the fractions pointers. The axial displacement of the shaft 15 brings an arm 40<a> thereon into the path of a pin, (not shown), on the pinion 40, so that when the zeroizing movement of the fractions shaft 15 takes place, the pinion 40, shaft 31 and gear 38 are also rotated to zeroize the units pointers. The movement of the sector 27 to bring about the above described zeroizing movements, is effected by energy stored in clock springs 60 during the first part of the movement of the starting handle 50, this handle being linked at 49 to a crank 48 on a shaft 28 which is also linked to a rod 47 actuating the pump-motor starting-switch. A toothed quadrant 51, fast on the shaft 28 wipes over a double-acting spring-held pawl 52<a> which prevents unintentional movement of the shaft 28 and ensures a full movement of the handle 50 in each direction being made before any return of the handle is possible. The quadrant 51 is linked at 54 both to a radius link 55 swinging about a fixed pivot 55a, and to a link 56 coupled to one arm 57a of a three-armed lever 57a, 57b, 57<c> on the shaft 28. The clock springs 60 are coupled at their inner ends to the hub of the three-armed lever, and at their outer ends to a plate 61 which moves only with the sector 27. A spring-pressed pawl 63 retains the sector 27 stationary while the handle 50 is moved through the first part of its movement to start the motor and to tension the springs 60, but when the arm 57b engages a pin 58 on the plate 61, the sector is positively moved past the pawl 63 and then completes its movement to zeroize the indicators, by energy stored in the springs 60. On stopping the motor, the arm 57<c> of the three-armed lever re-sets the sector 27. According to a modification, the handle 50, Fig. 4, may be mounted directly on a shaft 28 to which the clock springs 60 are anchored, the sector 27 having an arm 27<b> engaging a catch 64 to enable the springs to be tensioned during movement of the handle 50 to start the motor. The shaft 28 has a sector 67 which trips the catch 64 to initiate zeroizing. Specification 412,242 is referred to.