Improvements in or relating to water supply systems for concrete mixing machines

摘要

729,959. Dispensing measured quantities of liquids. BLAW KNOX, Ltd. Dec.. 21, 19,53 [Dec. 22, 1952], No. 32503/52. Class 106 (5). A water supply system for a concrete mixing machine, comprises a measuring tank 3, Fig. 1, having an outlet controlled by a valve 17 for delivering measured quantities of water from the tank to the drum of the machine, a further tank 4, having a float controlled valve 6, Fig. 3, governing the water inlet 5 thereto, the float being located in the tank 4 and the valve being arranged to shut off the inlet before the latter is submerged, and a further valve 16 for allowing water'to flow from the tank 4 to the tank 3. The valves 16, 17 are spring-loaded to their closed positions and adapted to be alternately opened by an arm 18 connected to a manually-operable lever 20. When the valve 16 is opened, water flows from the tank 4 by way of a pipe 8, chambers 9 and 11 and an inverted U-shaped pipe 23, Fig. 3, to the tank 3 until the latter is filled, this being indicated by a float 46 rising from a cage 45 into a dome 44 of transparent material communicating with an open-ended tube 46. The lever 20 is now moved to open the valve 17 and hence permit the water to flow from the tank 3 back through the pipes 26 and 23 and chambers 11 and 12 to an outlet 21 which delivers it to the drum of the concrete mixing machine. As the level of the water in the tank 3 falls it uncovers one end of a flexible pipe 33 the other end of which is connected by a pipe 34 to the top of the U-shaped pipe 23. The siphoning action in the latter is thus broken and the water flow arrested. The measured quantity delivered may be varied by adjusting the position of a rod 29 which passes through a stuffing box 30 and carries an inverted cup-shaped member 31 to which one end of the pipe 33 is connected. The rod 29, which together with the dome 44 is enclosed by a water-tight U-shaped plate 27 in the tank 4, is adjusted by means of a scale and clamped by a nut 40 and a flanged collar 41.