Pump system for conveying lubricating oil

Abstract

A pump system for conveying lubricating oil to a cutting chain of a chain saw is provided. The pump system comprises at least one first oil pump, wherein a quantity of oil being conveyed thereby is adjustable by an operator of the chain saw. The pump system also includes a basic oil pump that is connected in parallel to the adjustable oil pump.

1 . A pump system for conveying lubricating oil to a cutting chain of a chain saw, comprising: 
 at least one first oil pump, wherein a quantity of oil being conveyed thereby is adjustable by an operator of said chain saw; and    a basic oil pump that is connected in parallel to said adjustable first oil pump.    
   
   
       2 . A pump system according to  claim 1 , wherein a capacity of said basic oil pump is fixed.  
   
   
       3 . A pump system according to  claim 2 , wherein said at least one adjustable first oil pump has a lower maximum capacity than does said basic oil pump.  
   
   
       4 . A pump system according to  claim 1 , wherein said oil pumps are piston pumps having a piston portion that is rotatably driveable about a longitudinal axis thereof, wherein a circumferential inclined groove is provided on said piston portion, and wherein a control pin that is fixedly held in an axial direction in a housing of said pump system extends into said inclined groove.  
   
   
       5 . A pump system according to  claim 4 , wherein a respective piston of said oil pumps is fixed in position on a common piston portion.  
   
   
       6 . A pump system according to  claim 5 , wherein said pistons are monolithically formed with said piston portion.  
   
   
       7 . A pump system according to  claim 5 , wherein a pump housing is provided, wherein said pistons have different diameters, and wherein said pistons are guided in a stepped cylinder bore in said pump housing.  
   
   
       8 . A pump system according to  claim 7 , wherein said pump housing has a monolithic construction.  
   
   
       9 . A pump system according to  claim 1 , wherein a line valve is provided for adjusting a capacity of said at least one first adjustable oil pump.  
   
   
       10 . A pump system according to  claim 9 , wherein said line valve is disposed on an intake side of said adjustable oil pump.  
   
   
       11 . A pump system according to  claim 9 , wherein said line valve is a control valve.  
   
   
       12 . A pump system according to  claim 11 , wherein said control valve is infinitely variable.  
   
   
       13 . A pump system according to  claim 11 , wherein said control valve is a rotary piston valve.