System for controlling flushing of a cistern

Abstract

A control system for a cistern, the control system comprising a user activated sensor ( 13 ), a controller ( 14 ), a pump ( 15 ) and a pneumatic line ( 16 ) connected to the pump ( 15 ) and adapted to be connected to the drain valve ( 11 ) of a cistern ( 10 ), wherein the user activated sensor ( 13 ) and controller ( 14 ) are adapted to interpret a plurality of signals and operate the pump ( 15 ) in a predefined manner associated with a detected signal, thereby enabling a plurality of flushing actions to be effected using a single user activated sensor.

1 . A control system for a cistern including a drain valve, the control system comprising a user-activated sensor, a controller, a pump and a pneumatic line connected to the pump and adapted in use to be connected to the drain valve of the cistern, wherein the user-activated sensor and the controller are adapted to interpret a plurality of signals and operate the pump in a pre-defined manner associated with a detected signal, thereby enabling a plurality of flushing actions to be effected using a single user-activated sensor. 
   
   
       2 . A control system as claimed in  claim 1 , wherein the user-activated sensor is a motion detector, preferably an infrared proximity sensor, and the user-activated sensor is preferably operative to detect hand signals. 
   
   
       3 . A control system as claimed in  claim 1 , wherein the user-activated sensor is a pressure or touch sensor. 
   
   
       4 . A control system as claimed in  claim 1 , further comprising a pressure release valve incorporated in the pneumatic line which is configured to close when the pump is powered and to open when the pump is not powered. 
   
   
       5 . A control system as claimed in  claim 1 , wherein the cistern is a water-filled cistern and the control system further comprises one or more sensors for monitoring a water volume in the cistern which is to be flushed, and wherein the controller is appropriately configured to determine and effect the most economical flush of the system. 
   
   
       6 . A control system as claimed in  claim 5 , wherein the controller is configured to override a received flush signal if the flush signal does not demand the most economical flush. 
   
   
       7 . A control system as claimed in  claim 1 , wherein the controller is adapted to cause reverse as well as forward action of the pump in response to appropriate signals. 
   
   
       8 . A control system as claimed in  claim 1 , wherein the control system is powered by a low-voltage DC supply, preferably one of a 4V or 6V battery. 
   
   
       9 . A control system as claimed in  claim 1 , comprising a plurality of pumps, each configured to cause a specific and pre-defined flushing action, and wherein the controller associates each pump with a different signal received by the user-activated sensor and elects an appropriate pump to operate in reaction to a detected signal. 
   
   
       10 . A control system as claimed in  claim 1 , wherein the controller is configured to compensate for any variation in a power supply by adjusting the duration of a pneumatic pulse from the pump, such that, irrespective of the power of the power supply, constancy of the volume of air and consequent volume of the flush are maintained. 
   
   
       11 . A control system as claimed in  claim 1 , wherein the user-activated sensor comprises an infrared transmitter/receiver which is embodied with the controller in a PCB which houses one or more light-emitting indicators the controller being configured to activate the or each light-emitting indicator in a pre-defined manner to give an indication of a current status of the system, and preferably the infrared transmitter/receiver and the one or more light-emitting indicators are enclosed behind a multi-layer lens, each layer of the lens comprising an emulsion selected to transmit a frequency of light which corresponds to a frequency emitted by the one or more of the light-emitting indicators and the infrared transmitter/receiver. 
   
   
       12 . A control system as claimed in  claim 11 , wherein the PCB includes two light-emitting indicators and the controller is configured to display the first light-emitting indicator during a partial flush and the second light-emitting indicator during a whole flush, and preferably the light-emitting indicators are blue and green LEDs. 
   
   
       13 . A control system as claimed in  claim 1 , wherein the controller incorporates a timer which monitors a pre-defined period since the last flush of the system to generate a flush at the expiry of the pre-defined period and resets after each flush of the system. 
   
   
       14 . A lavatory cistern incorporating a control system as claimed in  claim 1 . 
   
   
       15 . A lavatory cistern as claimed in  claim 14 , wherein the user-activated sensor is associated with a mechanical pull chain or handle and operation of the pull chain or handle is translated into a signal to which the user-activated sensor is receptive.