Battery operated spray head retrofittable onto existing pump spray containers and producing substantially continuous spray

Abstract

A battery operated spray pump includes a piston pump having a double wave cam which is pushed by a pair of rotating cam pushers coupled to the electric motor via a gear transmission. The double wave cam has an unequal duty cycle, i.e. takes more time to expel fluid from the piston cylinder than it takes to fill the cylinder. The cam pushers rotate at a speed which, in conjunction with the duty cycle of the cam, produces a low pressure nearly constant stream.

1 . A battery operated liquid sprayer for use with a fluid container, said sprayer comprising: 
 a piston pump;    an electric motor; and    a transmission coupling said electric motor to said piston pump, said transmission including a double wave cam, wherein:    said piston pump has an intake cycle in which fluid is drawn from the fluid container and a spray cycle in which fluid is expelled from said pump,    said intake cycle and said spray cycle being of unequal duration.    
   
   
       2 . The sprayer according to  claim 1 , wherein: 
 said spray cycle is of longer duration than said intake cycle.    
   
   
       3 . The sprayer according to  claim 1 , wherein: 
 said spray cycle is approximately three times the duration of said intake cycle.    
   
   
       4 . The sprayer according to  claim 1 , wherein: 
 said intake cycle and said spray cycle each occur at least twice per second but fewer than ten times per second.    
   
   
       5 . The sprayer according to  claim 1 , wherein: 
 said intake cycle and said spray cycle each occur between 2.5 and 4 times per second.    
   
   
       6 . The sprayer according to  claim 1 , wherein: 
 said double wave cam includes a pair of concentric cylinders each having a cam surface disposed 180° relative to the other.    
   
   
       7 . The sprayer according to  claim 6 , wherein: 
 said transmission includes a pair of rotating cam pusher surfaces, each engaging a respective one of said cam surfaces.    
   
   
       8 . The sprayer according to  claim 7 , wherein: 
 said cam pusher surfaces are coupled to a gear which is coupled to said electric motor.    
   
   
       9 . The sprayer according to  claim 1 , further comprising: 
 a first one way valve coupled to an inlet of said piston pump, said first one way valve allowing liquid to enter through said inlet but not exit through said inlet; and    a second one way valve coupled to an outlet of said piston pump, said second one way valve allowing liquid to exit through said outlet but not enter through said outlet.    
   
   
       10 . The sprayer according to  claim 1 , wherein: 
 said spray cycle is of shorter duration than said intake cycle.    
   
   
       11 . A battery operated liquid sprayer for use with a fluid container, said sprayer comprising: 
 a pump;    an electric motor; and    a transmission coupling said electric motor to said pump, wherein    said pump has an intake cycle in which fluid is drawn from the fluid container and a spray cycle in which fluid is expelled from said pump,    said intake cycle and said spray cycle each occur between 2 and 10 times per second.    
   
   
       12 . The sprayer according to  claim 11 , wherein: 
 said spray cycle is of longer duration than said intake cycle.    
   
   
       13 . The sprayer according to  claim 11 , wherein: 
 said spray cycle is approximately three times the duration of said intake cycle.    
   
   
       14 . The sprayer according to  claim 11 , wherein: 
 said intake cycle and said spray cycle each occur between 2.5 and 4 times per second.    
   
   
       15 . The sprayer according to  claim 11 , wherein: 
 said intake cycle and said spray cycle each occur approximately three times per second.    
   
   
       16 . The sprayer according to  claim 12 , further comprising: 
 a first one way valve coupled to an inlet of said pump, said first one way valve allowing liquid to enter through said inlet but not exit through said inlet; and    a second one way valve coupled to an outlet of said pump, said second one way valve allowing liquid to exit through said outlet but not enter through said outlet.    
   
   
       17 . The sprayer according to  claim 11 , wherein: 
 said spray cycle is of shorter duration than said intake cycle.    
   
   
       18 . A battery operated liquid sprayer for use with a fluid container, said sprayer comprising: 
 a piston pump;    an electric motor; and    a transmission coupling said electric motor to said pump, wherein    said pump delivers a substantially constant stream at a pressure between 5 and 200 pounds per square inch.    
   
   
       19 . The sprayer according to  claim 18 , wherein 
 said pump has an intake cycle in which fluid is drawn from the fluid container and a spray cycle in which fluid is expelled from said pump,    said intake cycle and said spray cycle being of unequal duration.    
   
   
       20 . The sprayer according to  claim 19 , wherein: 
 said spray cycle is of longer duration than said intake cycle.    
   
   
       21 . The sprayer according to  claim 19 , wherein: 
 said spray cycle is approximately three times the duration of said intake cycle.    
   
   
       22 . The sprayer according to  claim 19 , wherein: 
 said intake cycle and said spray cycle each occur at least twice per second but fewer than ten times per second.    
   
   
       23 . The sprayer according to  claim 19 , wherein: 
 said intake cycle and said spray cycle each occur between 2.5 and 4 times per second.