Pump head and metering device

A pump head for a metering apparatus for a metered dispensing of a fluid, the pump head comprising:

• a head part having an outlet opening for the fluid to be dispensed outside the pump head;
• a first element that has a cutout, a wall bounding the cut-out at one side, and a passage opening introduced into the wall that brings the cutout directly or indirectly into fluidic communication with the outlet opening of the head part, with the first element being directly or indirectly connected to the head part in a direction of the wall;
• and
• a hollow piston having a passage channel that is fit into place in the cutout and is movably guidable up to the wall in the cut-out, wherein the hollow piston is not returned by a spring, wherein the passage channel is arranged in the hollow piston such that the passage opening is closable by the hollow piston on a movement of the hollow piston in the direction of the wall.