Piston pump of a hydraulic vehicle brake system

Abstract

The invention relates to a piston pump, in particular for brake pressure regulation in a hydraulic vehicle brake system. To control the pressure medium flow, piston pumps of the known type have an outlet valve which is accommodated in a valve lid. An outflow duct of the piston pump opens out into a pressure fluid conduit of a pump housing. As viewed in the direction of the longitudinal axis of the piston pump, the pressure fluid conduit is arranged above an end, which is situated in the interior of the pump housing, of the valve lid. The pressure fluid conduit is therefore at a relatively great distance from an outer side of the pump housing. The invention is directed to a special embodiment of the outflow fluid conduit of the piston pump, which makes it possible for the distance between the pressure fluid conduit and the outer side of the pump housing to be reduced. The pump housing may thereby be optimized in terms of installation space.

1 - 9 . (canceled) 
     
     
         10 . A piston pump, in particular for generating brake pressure in a hydraulic vehicle brake system, comprising:
 a pump housing,   a receiving bore disposed in the pump housing and receiving the piston pump; and   a valve cap closing the receiving bore from outside the pump housing, the valve cap having first conduit portions and second conduit portions of an outflow conduit of the piston pump which are embodied on the valve cap, the first conduit portions being disposed on an inner circumference of the valve cap and the second conduit portions being disposed on an outer circumference of the valve cap, wherein the conduit portions each discharge into the receiving bore on an end of the valve cap located in an interior of the receiving bore.   
     
     
         11 . The piston pump as defined by  claim 10 , wherein a second conduit portion of the outflow conduit of the piston pump communicates hydraulically with a pressure fluid conduit of the pump housing, and the pressure fluid conduit discharges into the receiving bore of the piston pump at a radial level of the valve cap which corresponds to the second conduit portions. 
     
     
         12 . The piston pump as defined by  claim 10 , wherein the first conduit portions and the second conduit portions are offset from one another in a circumferential direction of the valve cap, on the end of the valve cap located in the interior of the receiving bore. 
     
     
         13 . The piston pump as defined by  claim 11 , wherein the first conduit portions and the second conduit portions are offset from one another in a circumferential direction of the valve cap, on the end of the valve cap located in the interior of the receiving bore. 
     
     
         14 . The piston pump as defined by  claim 10 , wherein the valve cap, on the end located in the interior of the receiving bore, has an annular shoulder and an axially protruding collar that surrounds the annular shoulder on an outer circumference thereof. 
     
     
         15 . The piston pump as defined by  claim 11 , wherein the valve cap, on the end located in the interior of the receiving bore, has an annular shoulder and an axially protruding collar that surrounds the annular shoulder on an outer circumference thereof. 
     
     
         16 . The piston pump as defined by  claim 12 , wherein the valve cap, on the end located in the interior of the receiving bore, has an annular shoulder and an axially protruding collar that surrounds the annular shoulder on an outer circumference thereof. 
     
     
         17 . The piston pump as defined by  claim 14 , wherein a length of the first conduit portions in a direction of the longitudinal axis of the valve cap is equal to at least a length of the collar, and a length of the second conduit portions is equal to at least the length of the first conduit portions. 
     
     
         18 . The piston pump as defined by  claim 15 , wherein a length of the first conduit portions in a direction of the longitudinal axis of the valve cap is equal to at least a length of the collar, and a length of the second conduit portions is equal to at least the length of the first conduit portions. 
     
     
         19 . The piston pump as defined by  claim 16 , wherein a length of the first conduit portions in a direction of the longitudinal axis of the valve cap is equal to at least a length of the collar, and a length of the second conduit portions is equal to at least the length of the first conduit portions. 
     
     
         20 . The piston pump as defined by  claim 14 , wherein the annular shoulder of the valve cap is provided with a radially extending groove, which discharges into a first conduit portion of the outflow conduit of the piston pump. 
     
     
         21 . The piston pump as defined by  claim 17 , wherein the annular shoulder of the valve cap is provided with a radially extending groove, which discharges into a first conduit portion of the outflow conduit of the piston pump. 
     
     
         22 . The piston pump as defined by  claim 20 , wherein an annular groove is embodied on the annular shoulder and puts a plurality of first conduit portions hydraulically into contact with one another. 
     
     
         23 . The piston pump as defined by  claim 21 , wherein an annular groove is embodied on the annular shoulder and puts a plurality of first conduit portions hydraulically into contact with one another. 
     
     
         24 . The piston pump as defined by  claim 14 , wherein a bushing of the piston pump is braced on the annular shoulder and surrounded by the collar of the valve cap. 
     
     
         25 . The piston pump as defined by  claim 17 , wherein a bushing of the piston pump is braced on the annular shoulder and surrounded by the collar of the valve cap. 
     
     
         26 . The piston pump as defined by  claim 20 , wherein a bushing of the piston pump is braced on the annular shoulder and surrounded by the collar of the valve cap. 
     
     
         27 . The piston pump as defined by  claim 22 , wherein a bushing of the piston pump is braced on the annular shoulder and surrounded by the collar of the valve cap. 
     
     
         28 . The piston pump as defined by  claim 10 , wherein the first conduit portions and the second conduit portions of the valve cap are embodied such they can be made in non-metal-cutting fashion, by a non-cutting shaping work process. 
     
     
         29 . The piston pump as defined by  claim 19 , wherein the first conduit portions and the second conduit portions of the valve cap are embodied such they can be made in non-metal-cutting fashion, by a non-cutting shaping work process.