Solenoid pump

Abstract

A method of reducing or eliminating vibration in a linear reciprocating solenoid pump 10, the method comprising the steps of providing a solenoid pump 10 having a linear reciprocating plunger 14 and providing an electric circuit 48 to energize electro-motion means 16 of the solenoid pump 10, the electric circuit 48 energizing the electro-motion means 16 with an increased frequency of n times the frequency of normal mains electricity.

1 . A method of reducing or eliminating vibration in a linear reciprocating solenoid pump, the method comprising the steps of:
 providing a solenoid pump having a linear reciprocating plunger; and   providing an electric circuit to energize electro-motion means of the solenoid pump, the electric circuit energizing the electro-motion means with an increased frequency of n times normal mains electricity frequency.   
   
   
       2 . The method of  claim 1 , wherein n is a whole number greater than  1 . 
   
   
       3 . The method of  claim 1 , wherein the electric circuit includes a full bridge rectifier and a MOSFET to provide the increased frequency. 
   
   
       4 . The method of  claim 1  comprising providing the electric circuit with a bidirectional thyristor connected in series with the electro-motion means. 
   
   
       5 . The method of  claim 1 , further comprising selecting n to avoid operating the pump at its natural resonance frequency. 
   
   
       6 . A solenoid pump comprising: a pump housing having a liquid inlet, a liquid outlet, and a plunger chamber; a plunger received for linear reciprocating movement in the plunger chamber; electro-motion means for electromagnetically moving the plunger; and an electric circuit for energizing the electro-motion means with a frequency n times greater than normal mains electricity frequency, where n is a number greater than 1. 
   
   
       7 . The solenoid pump of  claim 6 , wherein the plunger is hollow and includes a plunger head which is slidably received in the plunger chamber and an elongate plunger rod which is slidably received in a pump chamber. 
   
   
       8 . The solenoid pump of  claim 6 , wherein the electric circuit includes a full bridge rectifier and a MOSFET for providing the increased frequency. 
   
   
       9 . The solenoid pump of  claim 6 , wherein the electric circuit includes a bidirectional thyristor in series with a coil of the electro-motion means. 
   
   
       10 . The solenoid pump of  claim 6 , wherein n is a whole number greater than 1. 
   
   
       11 . The solenoid pump of  claim 10 , wherein the increased frequency is different to the natural resonance frequency of the pump.