Pump and overflow valve assembly

Abstract

A pump and overflow valve assembly for a fluid pumping system includes a feed pump disposed in a feed pump housing, a return line in communication with the feed pump, an overflow valve disposed in the return line, the valve including a valve body and a valve housing being disposed in the feed pump housing. A spring is disposed between the valve housing and the valve body, and ajoining member is fixed to the valve body and projects outwardly from the valve housing. An adapter is mounted on the feed pump housing and a position switch is rotatably mounted on the adapter and provided with a control surface. Feed pump controlling means are disposed in the adapter and are responsive to selective rotation of the position switch to control operation of the overflow valve and the pump.

What is claimed is:  
     
         1 . A pump and overflow valve assembly for a fluid pumping system, the assembly comprising: 
 a feed pump disposed in a feed pump housing;    a return line in communication with said feed pump;    an overflow valve disposed in said return line, said overflow valve comprising a valve body and a valve housing, at least part of said valve housing being disposed in the feed pump housing;    a spring disposed between said valve housing and said valve body for biasing said valve body toward a closed position;    an adapter mounted on the feed pump housing;    ajoining member fixed to said valve body and projecting outwardly from said valve housing;    a rotatable position switch mounted on said adapter and provided with a circumferential contact surface; and    feed pump controlling means disposed in said adapter and responsive to selected rotation and positioning of said position switch to control operation of said overflow valve and said pump.    
     
     
         2 . The assembly in accordance with  claim 1 , wherein said joining piece is provided with a locating hole in an end portion of said joining piece disposed in the position switch, and a pin is locked into said position switch and extends perpendicularly to a longitudinal axis of the joining piece, and projects through the locating hole in said joining piece.  
     
     
         3 . The assembly in accordance with  claim 2 , wherein a free end of the pin is held in a blind hole disposed in said position switch, a head piece of the pin being screwed into an internal thread provided in the position switch blind hole.  
     
     
         4 . The assembly in accordance with  claim 2  wherein said position switch, when rotated, causes the valve body to be moved axially.  
     
     
         5 . The assembly in accordance with  claim 1  wherein said position switch is provided with at least two control surfaces, and wherein said adapter is provided with cams having surfaces complementary to the control surfaces of the position switch.  
     
     
         6 . The assembly in accordance with  claim 1  wherein said adapter and said position switch are removable separately and together from the housing of the feed pump.  
     
     
         7 . The assembly in accordance with  claim 1  wherein an accommodation opening is provided in the housing of the feed pump to retain said adapter in place and prevent said adapter from rotating.  
     
     
         8 . The assembly in accordance with  claim 7 , wherein said adapter is provided with an external contour complementary to the shape of the accommodation opening.  
     
     
         9 . The assembly in accordance with  claim 1  wherein said adapter comprises a plurality of housing components.  
     
     
         10 . The assembly in accordance with  claim 9 , wherein a first of said housing components is provided with a projection defining a through-hole provided for passage therethrough of said overflow valve, the projection projecting towards a second of said housing components when said housing components are assembled, and said second housing component is provided with a recess adapted to receive an external contour of the projection.  
     
     
         11 . The assembly in accordance with  claim 9 , wherein said housing components are attached to each other.  
     
     
         12 . The assembly in accordance with  claim 1  wherein a cross section of a free end portion of said joining member is of a shape corresponding to a blind hole in said position switch.  
     
     
         13 . The assembly in accordance with  claim 12 , wherein the cross sectional shape in the blind hole of said position switch is configured such that said joining member is held in a predetermined position in said position switch.  
     
     
         14 . The assembly in accordance with  claim 12 , wherein a connector portion of said position switch is provided with a control surface and wherein the connector portion is insertable into said adapter, and wherein when said position switch is assembled, the control surface is in contact with a mating surface provided in said adapter.