Abstract: A quick and dry coupling for coupling together devices such as fluid lines. One embodiment of the coupling includes a pair of heads in which is provided mating members having mating surfaces for moving the mating members in opposite directions away from one another towards an open position and to permit movement of the mating members towards one another when the pair of mating members are turned in the opposite direction relative to one another, a latch coacting between the heads for selectively being movable to an unlatched position, to an intermediate position, and to a latched position for providing the attached condition of the coupling. Springs are provided for moving the pair of mating members into a closed position in which fluid flow is stopped and the latch is moved from the latched position to the intermediate position.

Abstract: A proportional mixing unit for accurately metering the desired amounts of a liquid concentrate and a liquid diluent, completely mixing the concentrate and diluent together, and holding the mixture until needed. A constant volume pump is used to pump a constant volume of the liquid concentrate. A pressure regulator maintains the liquid diluent at a constant pressure. A variable volume pump is used to mix the liquid concentrate from the constant volume pump and the liquid diluent from the pressure regulator and to pump a variable volume of the mixture to a holding tank. By varying the volume of the variable volume pump, the proportion of liqiuid concentrate to liquid diluent is accurately varied.