High-Pressure Pump for a Fuel Injection System of an Internal Combustion Engine

Abstract

A high-pressure pump having at least one pump element, with a pump piston which is driven in a reciprocating motion and is guided displaceably in a cylinder bore of a pump housing part and which in the cylinder bore defines a pump work chamber that can be filled with fuel via a suction valve in the intake stroke of the pump piston. The suction valve has a valve member, which opens into the pump work chamber and cooperates with a valve seat. In its end region toward the suction valve, the pump piston has a blind bore, into which the valve member of the suction valve plunges, and in which a closing spring is disposed, which acts on the valve member and is braced on one end on the pump piston and on the other on the valve member. The valve member is guided displaceably in the blind bore of the pump piston.

1 - 5 . (canceled)  
   
   
       6 . In a high-pressure pump for a fuel injection system of an internal combustion engine, the high-pressure pump having at least one pump element, which has a pump piston driven in a reciprocating motion and guided displaceably in a cylinder bore of a pump housing part, the piston in the cylinder bore defining a pump work chamber that can be filled with fuel via a suction valve in the intake stroke of the pump piston, the suction valve having a valve member opening into the pump work chamber and cooperating with a valve seat, and the pump piston, in its end region oriented toward the suction valve having a blind bore into which the valve member of the suction valve plunges and in which a closing spring, acting on the valve member is disposed, the closing spring being braced on one end on the pump piston and on the other on the valve member, the improvement wherein the valve member is guided displaceably in the blind bore of the pump piston.  
   
   
       7 . The high-pressure pump as defined by  claim 6 , wherein the closing spring in the blind bore is disposed in a spring chamber defined by the pump piston and the valve member.  
   
   
       8 . The high-pressure pump as defined by  claim 7 , wherein the valve member is embodied as cup-shaped and protrudes with its open end into the blind bore in the pump piston; wherein the closing spring protrudes into the valve member; and wherein the valve member, with its closed end protruding out of the blind bore, cooperates with the valve seat.  
   
   
       9 . The high-pressure pump as defined by  claim 8 , wherein the valve member has at least one opening through which the spring chamber communicates with the pump work chamber.  
   
   
       10 . The high-pressure pump as defined by  claim 6 , wherein the valve seat is embodied in the same pump housing part as the cylinder bore in which the pump piston is guided.  
   
   
       11 . The high-pressure pump as defined by  claim 7 , wherein the valve seat is embodied in the same pump housing part as the cylinder bore in which the pump piston is guided.  
   
   
       12 . The high-pressure pump as defined by  claim 8 , wherein the valve seat is embodied in the same pump housing part as the cylinder bore in which the pump piston is guided.  
   
   
       13 . The high-pressure pump as defined by  claim 9 , wherein the valve seat is embodied in the same pump housing part as the cylinder bore in which the pump piston is guided.