Flow control for a continuous-flow water heater

Abstract

A flow control for a continuous-flow water heater is used to control the flow of gas to a burner ( 24 ) of a heat exchanger ( 29 ) as a function of the passage of water, in which only one operating element has to be actuated. The reduction in apertures through the housing wall of the flow control, reduces the risk of leaks. Furthermore, manufacturing expenditure is minimized. To this end, in addition to the operating element ( 8 ), a switching element ( 9 ) is rotatably mounted on a spindle ( 7 ) projecting from the water-carrying housing ( 5 ), wherein a rotary movement of the operating element ( 8 ) can be transmitted via drivers ( 10; 11 ) to the switching element ( 9 ), which also has a switching contour ( 13 ) by means of which a fixedly arranged microswitch ( 14 ) can be actuated, by means of which an electronic ignition and monitoring device ( 3 ) can be electrically actuated, by means of which gas flow to the burner can be shut off.

What is claimed is: 
     
         1 . Flow control for a continuous-flow water heater, comprising a water part ( 1 ) controlling the passage of water to a heat exchanger ( 29 ) wherein the quantity of water can be manually set by an operating element ( 8 ) attached to a spindle ( 7 ) projecting from the water-carrying housing ( 5 ), a gas part ( 2 ) with an electronic ignition and monitoring device ( 3 ) controlling the gas flow as a function of the passage of water to an atmospheric burner ( 24 ), a mechanical transmission ( 4 ) which transmits, as a function of the passage of water and a water membrane ( 20 ), a steering movement initially from the interior of the water-carrying housing ( 5 ) to the exterior and then from there into the gas-carrying housing ( 6 ) to a valve controlling the amount of gas, characterised in that a switching element ( 9 ) is rotatably mounted on the spindle ( 7 ), wherein a rotary movement of the operating element ( 8 ) can be transmitted by driver ( 10 ;  11 ) to the switching element ( 9 ), and that the switching element ( 9 ) has a switching contour ( 13 ), by means of which a fixedly arranged microswitch ( 14 ) can be actuated which shuts off the gas flow to the burner ( 24 ) by means of the electronic ignition and monitoring device ( 3 ) and an electrically actuatable valve ( 22 ). 
     
     
         2 . Flow control for a continuous-flow water heater according to  claim 1 , characterised in that the electrically actuatable valve is formed by the servo valve ( 22 ) of the electronic ignition and monitoring device ( 3 ). 
     
     
         3 . Flow control for a continuous-flow water heater according to  claim 1 , characterised in that the driver ( 10 ;  11 ) is formed by at least one rib ( 10 ) located on the operating element ( 8 ) and projecting into slots ( 11 ) located on the switching element ( 9 ). 
     
     
         4 . Flow control for a continuous-flow water heater according to  claim 1 , characterised in that the switching element ( 9 ) is connected to the operating element ( 8 ) by locking hooks ( 12 ) and detent ( 12   a ). 
     
     
         5 . Flow control for a continuous-flow water heater according to  claim 2 , characterized in that the driver ( 10 ;  11 ) is formed by at least one rib ( 10 ) located on the operating element ( 8 ) and projecting into slots ( 11 ) located on the switching element ( 9 ). 
     
     
         6 . Flow control for a continuous-flow water heater according to  claim 2 , characterized in that the switching element ( 9 ) is connected to the operating element ( 8 ) by locking hooks ( 12 ) and detent ( 12   a ). 
     
     
         7 . Flow control for a continuous-flow water heater according to  claim 5 , characterised in that the switching element ( 9 ) is connected to the operating element ( 8 ) by locking hooks ( 12 ) and detent ( 12   a ). 
     
     
         8 . Flow control for a continuous-flow water heater according to  claim 1 , characterized in that the mechanical transmission ( 4 ) transmits the steering movement by a Venturi nozzle ( 21 ) housed in the water-carrying housing ( 5 ). 
     
     
         9 . A flow control for a continuous-flow water heater comprising:
 a water part having a fluid circuit for fluid flow of water through the flow control, a rate of water flow regulated by the flow control;   a water membrane disposed in the water flow and displaced proportionate to the water flow rate;   a gas part having a fluid circuit for fluid flow of gas through the flow control, a rate of gas flow regulated by the flow control;   an operating element providing operator control of the water flow rate, the operating element operatively coupled to a switching element, the operating element and switching element supported on a spindle for coupled rotation;   a microswitch operatively coupled to the switching element by a switching contour disposed on the switching element, the microswitch controlling the electrical actuation of an electrically-actuated valve; wherein the electrically-actuated valve controls the gas flow rate through the gas part and includes a main valve and a regulating valve;   a transmission disposed between the regulating valve in the gas part and the water membrane in the water part providing proportional flow rate control between the water flow through the water part and the gas flow through the gas part.   
     
     
         10 . The flow control of  claim 9 , further comprising a Venturi nozzle and a pre-setting element located in the water part to set a preset value corresponding to a water flow rate supply condition. 
     
     
         11 . The flow control of  claim 9 , wherein the operating element is rotatably mounted to the flow control between an off-position and through a range of flow rate control from a minimum water outlet temperature to a maximum outlet temperature, wherein, when the operating element is in an off-position, the microswitch activates the electrically-actuated valve controlling the gas-flow rate to stop gas flow through the flow control. 
     
     
         12 . The flow control of  claim 11 , wherein the, when the operating element is rotated to a minimum water outlet temperature position, the proportion of water flow rate to gas flow rate through the flow control is maximized; and when the operating element is rotated to a maximum water outlet temperature position, the proportion of water flow rate to gas flow rate through the flow control is minimized.