Electronically controllable valves and mixing valves

Abstract

Two problems with existing electronically controlled mixing valves for domestic use is their size and difficulty accessing and repairing them. Their size means that they often become hidden behind wall linings, and because of the way in which they are plumbed into the pipework of a house, they are difficult to access and remove for repair or replacement. Disclosed is a compact and replaceable mixing valve cartridge that can be mated to a fixed fitting that is permanently plumbed into the pipework of a house. The compact size allows the cartridge to be positioned behind the type of removable face plates that are often installed over existing manually operated mixing valves. Simplified valve actuators and a compact mixing and temperature sensing configuration have facilitated the compact size. The valve cartridge can simply be accessed, unbolted and removed, without the need for extensive plumbing re-work.

1 . An electronically controllable mixing valve cartridge, the valve cartridge comprising:
 at least two fluid inlets and at least one fluid outlet;   at least one temperature sensor;   at least one movable valve member and at least one actuator configured to move each said movable valve member; and   an electronic control system configured for receiving inputs from an input device and adapted to receive inputs from each said temperature sensor and to control the operation of each said actuator,   wherein the valve cartridge has a single substantially flat mating face that includes the at least two fluid inlets and the at least one fluid outlet, and   wherein the valve cartridge is configured such that a mechanical fastening system is used to hold the mating face of the valve cartridge securely to a complimentary fixable valve fitting to form a leak resistant seal between the mating face and the fixable valve fitting.   
     
     
         2 . A valve cartridge as claimed in  claim 1 , wherein each said actuator includes an electric motor. 
     
     
         3 . A valve cartridge as claimed in  claim 2 , wherein a direction of flow of a fluid through the fluid inlets and through each said fluid outlet is a direction of flow that is substantially aligned with a rotational axis of each said electric motor. 
     
     
         4 . A valve cartridge as claimed in  claim 1 , wherein each said actuator includes a linear actuator. 
     
     
         5 . A valve cartridge as claimed in  claim 4 , wherein a direction of flow of a fluid through the fluid inlets and through each said fluid outlet is a direction of flow that is substantially aligned with a direction of movement of each said movable valve member. 
     
     
         6 . A valve cartridge as claimed in  claim 1 , wherein the complimentary fixable valve fitting is a fitting that is connectable to the pipework of a plumbing installation and that has complimentary fluid outlets and a fluid inlet or fluid inlets. 
     
     
         7 . A valve cartridge as claimed in  claim 6 , wherein the mating face of the valve cartridge is configured for establishing a sealed connection between each said fluid inlet and each said fluid outlet of the valve cartridge and the fixable valve fitting. 
     
     
         8 . A valve cartridge as claimed in  claim 1 , wherein the valve cartridge includes a mixing chamber that is configured to mix two or more fluid flows and which is situated downstream of each said movable valve member and upstream of the at least one temperature sensor. 
     
     
         9 . A valve cartridge as claimed in  claim 8 , wherein the valve cartridge includes transfer passages through which fluid flows as the fluid approaches the mixing chamber, and the transfer passages are configured to create a swirling motion within the mixing chamber. 
     
     
         10 . A valve cartridge as claimed in  claim 9 , wherein the mixing chamber is substantially cylindrical in shape and the transfer passages are each configured to direct the fluid in a direction that is substantially tangential to a circle defining a perimeter of the cylindrical mixing chamber. 
     
     
         11 . A valve cartridge as claimed in  claim 9 , wherein the cross-sectional area of the transfer passages reduces in a direction of flow towards the mixing chamber. 
     
     
         12 . A valve cartridge as claimed in  claim 1 , wherein the valve cartridge also includes a flow sensing means. 
     
     
         13 . A valve cartridge as claimed in  claim 12 , wherein a temperature sensing element of the temperature sensor is supported on a probe or shaft, and a rotatable element of the flow sensing means rotates about an axis that is coaxial with the shaft or probe. 
     
     
         14 . An electronically controllable mixing valve assembly including an electronically controllable mixing valve cartridge as claimed in  claim 1  and a fixable valve fitting, the electronically controllable mixing valve cartridge being connectable to the fixable valve fitting using a mechanical fastening system, and the fixable valve fitting being connectable to a plumbing system of a building and configured to direct fluid to the at least two fluid inlets of the valve cartridge and to receive fluid from the at least one fluid outlet of the valve cartridge, and being configured to allow leak resistant seals to be established between the mating face of the electronically controllable mixing valve cartridge and a complimentary mating face of the fixable valve fitting. 
     
     
         15 . A valve cartridge as claimed in  claim 2 , wherein each said actuator includes a linear actuator. 
     
     
         16 . A valve cartridge as claimed in  claim 3 , wherein each said actuator includes a linear actuator. 
     
     
         17 . A valve cartridge as claimed in  claim 15 , wherein a direction of flow of a fluid through the fluid inlets and through each said fluid outlet is a direction of flow that is substantially aligned with a direction of movement of each said movable valve member. 
     
     
         18 . A valve cartridge as claimed in  claim 16 , wherein a direction of flow of a fluid through the fluid inlets and through each said fluid outlet is a direction of flow that is substantially aligned with a direction of movement of each said movable valve member. 
     
     
         19 . A valve cartridge as claimed in  claim 2 , wherein the complimentary fixable valve fitting is a fitting that is connectable to the pipework of a plumbing installation and that has complimentary fluid outlets and a fluid inlet or fluid inlets. 
     
     
         20 . A valve cartridge as claimed in  claim 5 , wherein the complimentary fixable valve fitting is a fitting that is connectable to the pipework of a plumbing installation and that has complimentary fluid outlets and a fluid inlet or fluid inlets.