Abstract: A reciprocating-piston pump having an electromagnetically driveable reciprocating piston, which is mounted with a restoring spring, for feeding a liquid, an impact damper composed of an elastomer for damping an impact of the reciprocating piston at the end of a feed phase, a core flange which is situated opposite the reciprocating piston, with a gap which is dependent on the position of the reciprocating piston being provided between the reciprocating piston and the core flange. The kinetic energy of the reciprocating piston during an early feed interval of a feed phase is absorbed primarily by the restoring spring and the feed of the liquid, and in that the kinetic energy of the reciprocating piston during a late feed interval of a feed phase is absorbed primarily by the hydraulic damping of the liquid present in the gap.

Abstract: A fuel valve (10) for supplying fuel to an auxiliary heating device in a motor vehicle comprises a magnet coil (12), a magnet armature (14) and a spring (16) which can be compressed by the magnetic force generated when a pick-up voltage is applied to the magnet coil and causes the magnet armature to move; at a maximum residual voltage applied to the magnet coil, the spring overcomes the magnetic force and expands. According to the invention, a spring force-distance travelled characteristic curve (FWK) is adapted in such a way that it lies, for all relevant values of distance travelled, between a magnetic force-distance travelled characteristic curve with applied pick-up voltage (MWKA) and a magnetic force-distance travelled characteristic curve with applied maximum residual voltage (MWKR).

Abstract: The invention relates to a reciprocating-piston pump having an electromagnetically driveable reciprocating piston, which is mounted with a restoring spring, for feeding a liquid, an impact damper composed of an elastomer for damping an impact of the reciprocating piston at the end of a feed phase, a core flange which is situated opposite the reciprocating piston, with a gap which is dependent on the position of the reciprocating piston being provided between the reciprocating piston and the core flange. Here, the invention is characterized in that the kinetic energy of the reciprocating piston during an early feed interval of a feed phase is absorbed primarily by the restoring spring and the feed of the liquid, and in that the kinetic energy of the reciprocating piston during a late feed interval of a feed phase is absorbed primarily by the hydraulic damping of the liquid present in the gap.