first valve body 6 is received in a manner capable of reciprocation in the bore 2 in the valve housing 1 in the region where the connecting conduit 3 discharges into the pump chamber on the first valve body 6 a first valve seat face 7 is formed which is in contact with a first valve seat edge 8 that is embodied in the valve housing 1 one end 9 of the first valve body 6 is shown in cutaway form the end 9 shown cut away of the first valve body 6 is coupled with an actuating device not shown the actuating device can for instance be a magnet or a piezoelectric actuator a groove 10 is formed in the end face on the other end of the first valve body 6 the first valve body 6 is spaced apart with its free end from a second valve body 11 by a spacing or stroke h 1 a second valve seat face 17 is embodied on the second valve body 11 it is in contact with a second valve seat edge 18 that is embodied in the valve housing 1 the second valve body 11 furthermore has a central through bore 12 in which a throttle 13 is embodied the second valve body 11.