| 摘要 |
1,169,420. Dispensing liquids. VEEDER INDUSTRIES Inc. 15 Dec., 1967 [22 Dec., 1966], No. 57072/67. Heading A4T. [Also in Division B1] In apparatus for dispensing two fluids to a common discharge nozzle and at a pre-determined total flow rate in proportions controlled by an adjustable proportioning valve automatically adjusted to a preselected ratio, there is a flow control to close off the fluid flow to the discharge nozzle and to recirculate them to permit adjustment of the proportioning valve to a new ratio before delivery of the fluids to the nozzle. As shown in a conventional arrangement for dispensing two grades of fuel, they are pumped by pumps 16, 18 to a proportioning valve 24 through flow meters 30, 32. The proportioning valve 24 is adjusted by a subtracting differential 28 which has inputs from flow-meter 32 and from a speed changing mechanism 44 which is controlled by screening differential 38 and by variator 48 on which the preselected ratio is set. The return valve 72 has valve members 74, 76 each having two positions in which the incoming flow is either recirculated, or delivered to the discharge nozzle. At the end of the dispensing operation a handle 85 is turned to an OFF position to reset the number wheels 54 of a register 50, also operating a linkage 80 which moves the valve members 74, 76 to the recirculating position. When the nozzle 10 is next lifted from its storage position, the pump motors 20, 22 will be energized and the proportioning valve thus readjusted before the handle 85 is turned to the ON position to open flow to the discharge nozzle. Alternatively, the linkage so may be connected to a presettable control mechanism 88 for terminating delivery when preselected amount has been dispensed. In another embodiment (Fig. 3, not shown) the screening differential (138) provides an input to a differential (200) the output of which is transmitted to the variator (148) and to the register (150) by shafts (202, 204) having a variator brake (206) and a register brake (208) connected to a common brake control (210) for engaging one of them and simultaneously releasing the other. The brake control is operated by the return valve control linkage (180) whereby automatic resetting of the register is provided. |
