Nozzle insert for boosting pump inlet pressure

Abstract

A pump assembly includes a pump housing including an inner surface, a pump inlet and an excess flow passage, a filter assembly including a spout extending into the housing, and an insert located within and secured to the housing, and including a first surface spaced from the inner surface and producing therebetween an annular nozzle communicating with said excess flow passage, the nozzle directing a first fluid stream exiting the excess flow passage toward a second fluid stream exiting the spout, the fluid streams flowing toward the pump inlet.

1 . A pump assembly comprising:
 a housing including a conical inner surface and an excess flow passage;   a spout directing a fluid stream into the housing;   an insert mounted between the housing and spout, including an outer surface and an end surface facing directly downstream meeting to form a corner, the corner spaced from said inner surface and producing therebetween a nozzle directing a first fluid stream from the excess flow passage toward said fluid stream.   
     
     
         2 . The pump assembly of  claim 1 , wherein:
 the inner surface is a conical surface inclined inward and toward a pump inlet, producing a distance between the inner surface and the cylindrical outer surface, the distance decreasing linearly as distance from the pump inlet decreases.   
     
     
         3 . The pump assembly of  claim 1 , wherein:
 the housing inner surface is a conical surface inclined inward toward a pump inlet at a first angle from an axis extending toward the pump inlet; and   the insert outer surface includes a portion having a conical surface inclined inward toward the pump inlet at a second angle from the axis, the second angle less than the first angle such that a distance between the conical inner surface and the conical portion of the outer surface decreases as the distance from the pump decreases.   
     
     
         4 . The pump assembly of  claim 1 , wherein the insert is secured to the housing by mutually engaged threads formed on the insert and the housing. 
     
     
         5 . The pump assembly of  claim 1 , wherein the insert is secured to the housing by bonding. 
     
     
         6 . The pump assembly of  claim 1 , wherein:
 the housing inner surface is a conical surface inclined inward and toward a pump inlet and the housing includes a shoulder facing toward and spaced from the spout; and   the insert includes a flange that contacts the shoulder, said contact establishing a position of the insert in the housing.   
     
     
         7 . The pump assembly of  claim 6 , wherein the outer surface is cylindrical and extends away from the flange, along an axis toward the pump inlet; and
 the cylindrical outer surface meets the end surface to form the corner.   
     
     
         8 . A pump assembly comprising:
 a housing including an excess flow passage and a conical inner surface inclined inward toward a pump inlet at a first angle from an axis extending toward the pump inlet;   a spout directing a fluid stream into the housing;   an insert secured to the housing, including an outer surface having a portion with a conical surface inclined inward toward the pump inlet at a second angle from the axis, the second angle less than the first angle such that a distance between the conical inner surface and the conical portion of the outer surface decreases as the distance from the pump decreases, producing therebetween a nozzle directing a first fluid stream from the excess flow passage toward said fluid stream.   
     
     
         9 . The pump assembly of  claim 8 , wherein:
 the insert includes spaced nubs extending radially outward from said outer surface into contact with the inner surface, the nubs defining the distance between the inner surface and the outer surface at a downstream end of the insert.   
     
     
         10 . The pump assembly of  claim 9 , wherein the insert is secured to the housing by mutually engaged threads formed on the insert and the housing. 
     
     
         11 . The pump assembly of  claim 8 , wherein the insert is secured to the housing by mutually engaged threads formed on the insert and the housing. 
     
     
         12 . The pump assembly of  claim 9 , wherein the insert is secured to the housing by bonding. 
     
     
         13 . The pump assembly of  claim 8 , wherein the insert is secured to the housing by bonding. 
     
     
         14 . The pump assembly of  claim 8 , wherein:
 the insert includes an end surface facing directly downstream and the end surface and the outer surface meet to form a circular corner.   
     
     
         15 . A pump assembly comprising:
 a housing including an excess flow passage and a conical inner surface inclined inward toward a pump inlet at a first angle from an axis extending toward the pump inlet;   an insert secured to the housing, including an outer surface having a portion with a conical surface, adjacent to the inner surface, inclined inward toward the pump inlet at a second angle from the axis, the second angle less than the first angle such that a distance between the conical inner surface and the conical portion of the outer surface decreases as the distance from the pump decreases, forming a nozzle, the outer surface further having a cylindrical portion adjacent to the excess flow passage.   
     
     
         16 . The pump assembly of  claim 15 , wherein the insert further comprises nubs extending outward from the outer surface into contact with the inner surface. 
     
     
         17 . The pump assembly of  claim 15 , wherein the insert is secured to the housing by bonding. 
     
     
         18 . The pump assembly of  claim 15 , wherein the insert is secured to the housing by mutually engaged threads formed on the insert and the housing.