Patent GB-938474-A (GB)
Title: Arrangement for the automatic zeroising of counting mechanisms
IPC: G06C15/00
Filed: 1960-02-05
Abstract: 938,474. Zeroizing-mechanism. KIENZLE APPARATE G.m.b.H. Feb. 5, 1960 [Feb. 24, 1959], No. 4184/60. Class 106 (1). In an arrangement for automatically zeroizing the counter of a liquid dispensing apparatus, a force-storage means is tensioned during the initial part of a delivery operation by members driven by the drive shaft of the counter and released to effect zeroizing, release of the force-storage means being effected, for example, by the lifting of a delivery hose nozzle. Zeroizing operation.- When the delivery hose is lifted, a lever 26, Fig. 2, is swung counterclockwise and lifts a locking lever 22 to release a locking disc 17 on a shaft 16 thereby permitting a spring 11 which has been tensioned during the previous delivery operation to effect rotation of the zeroizing shaft 31 of the counter (not shown) through a pawl-and-ratchet mechanism 27, 28, Fig. 3. A disc 32 is also rotated and initially moves a further disc 34 against the action of spring 38 until a stop 35 is released from a slot 33 in the disc 32. After a zeroizing rotation of the shaft 31 and disc 32 through about 140 degrees, the pin 35 again drops in the slot 33 to allow the spring 38 to effect a reverse rotation of about 50 degrees as is required for the zeroizing operation, a stop 36 disengaging the pawl 28 to permit the rotation. The lever 26 is raised for a short time only so the disc 17 is again locked by the lever 22 after zeroizing has been completed. Zeroizing may be effected manually by attaching a hand crank to a coupling piece 57 on the shaft 31. Delivery operation.-During liquid delivery, the counter (not shown) drives a shaft 1 through a bevel gear 2. The shaft 1 drives through gearing 3, 4, 5, 6, a one-revolution coupling 7 and a gear 9 and gear-wheel 10 which is connected to the outer end of the spring 11. The spring 11 is always fully tensioned if at least the minimum prescribed quantity of liquid has been delivered, the coupling 7 preventing over tensioning of the spring 11. The coupling 7 is also arranged, in the event of a sub-minimum delivery of liquid, to effect full tensioning of the spring during the next delivery provided this exceeds the minimum quantity by a certain amount. The coupling 7 comprises a locking wheel 40 and two coupling discs 41, 42 screwed together, the disc 41 being slightly larger than the disc 42 which carries a pawl 44 adapted to engage with the locking wheel 40. After a normal delivery operation, the spring 11 is fully tensioned and a lever 50 rests with its end 55 in a recess 48 of the disc 42, the pawl 44 being disengaged from the locking wheel 40. During subsequent zeroizing, the raising of the lever 22 raises also the lever 50 which is shifted slightly laterally by a spring 54 to rest on the periphery of the disc 41, this position being maintained until delivery commences, whereupon the shaft 1 and locking wheel 40 and also, through the pawl 44, the discs 41, 42 all rotate, the lever 50 dropping into a recess in the disc 41. When the position of Fig. 2 is reached, the spring 11 is fully tensioned and the lever 50 slips down in to the recess 48 of the disc 42, thereby engaging a stop on the pawl 44 to lift the pawl out of engagement with the locking wheel 40, the shaft 1 subsequently running idly. If the minimum quantity of liquid has not been delivered at the previous delivery, the coupling remains stationary in a position approximate to that of Fig. 2, the coupling 7 remaining engaged. On initiation of zerozing, the lever 50 is lifted on to the larger disc 41 and after the coupling 7 has completed the revolution not completed in the previous delivery, the normal revolution of the coupling 7 described above, takes place. Locking arrangement, Fig. 8. Means are provided to prevent the commencement of delivery before zeroizing has been completed and to prevent zeroizing while delivery is being effected. When the delivery hose 66 is lifted, the shaft 16 first moves through 50 degrees in the counter-clockwise direction, a pawl 76 sliding into the position shown so that, on the subsequent clockwise movement of the shaft 16, the pawl 76 pivots a pawl 71 counterclockwise, thereby releasing a lever 60 for clockwise rotation to allow a linkage 67, 68 to switch on the pump motor 69. A pawl 75 is also pivoted to engage a locking wheel 59 on the zeroizing shaft 31 which is thereby locked during the delivery operation. At the conclusion of delivery the hose 66 is hung up and the arrangement returns to the position shown. Modification.-The coupling 7 may comprise three discs instead of the two discs 41, 42 and function as a two-revolution coupling. An escapement governor may be incorporated to control the speed of the zeroizing operation.