Electromagnetic valve-controlled fuel injection pump for internal combustion engines, especially diesel engines

A solenoid-valve-controlled fuel-injection pump for an internal combustion engine, comprising:

• a high-pressure region;
• a low-pressure region;
• a low-pressure compensating piston arranged in the low-pressure region in order to compensate for pressure fluctuations in the low-pressure region;
• a valve seat;
• a solenoid valve including a valve needle that separates the high-pressure region from the low-pressure region and connects the high-pressure region and the low-pressure region in a pump housing, via the valve seat, wherein:
• an injection period is controlled by an opening of the solenoid valve, and
• the low-pressure compensating piston is positioned coaxially to the valve needle and includes a component part that is separate from the valve needle;
• a low-pressure compensating spring;
• and
• a stroke-limit stop for the low-pressure compensating piston provided on a rear end of a low-pressure compensating piston chamber opposite to the valve needle, the low-pressure compensating piston chamber being coaxially contiguous to the low-pressure region in the pump housing, and the stroke-limit stop protecting the low-pressure compensating spring, wherein:
• in the low-pressure compensating piston chamber, the low-pressure compensating piston is positioned so as to be axially movable in opposition to a resistance of the low-pressure compensating spring acting on a back side of the low-pressure compensating piston.

A solenoid-valve-controlled fuel-injection pump for an internal combustion engine, comprising:

• a high-pressure region;
• a low-pressure region;
• a low-pressure compensating piston arranged in the low-pressure region in order to compensate for pressure fluctuations in the low-pressure region;
• a valve seat;
• and
• a solenoid valve including a valve needle that separates the high-pressure region from the low-pressure region and connects the high-pressure region and the low-pressure region in a pump housing, via the valve seat, wherein:
• an injection period is controlled by an opening of the solenoid valve;
• the low-pressure compensating piston is positioned coaxially to the valve needle and includes a component part that is separate from the valve needle;
• and
• an end of the low-pressure compensating piston facing the solenoid valve includes a piston rod that extends into a cylindrical guide hole introduced into the valve needle in a region of the valve seat, the piston rod guiding the low-pressure compensating piston.