Metering device

A metering device for the metered application of a highly viscous product onto a substrate, comprising:

• a housing with an inner side and an outer side, a first end which faces the substrate during actuation of the metering device and a second end opposite from the first end, wherein the housing comprises a housing opening in the area of the first end,
• a cartridge which is arranged at least substantially within the housing, and which forms an internal receiving space for the highly viscous product, wherein the cartridge comprises a cartridge opening in the area of the first end of the housing through which the highly viscous product can be dispensed from the metering device onto the substrate,
• a piston which is arranged within the housing and at least partially within the cartridge and which forms a delimitation of the receiving space opposite the cartridge opening, wherein, during the actuation of the metering device, a movement of the housing relative to the cartridge brings about a movement of the piston relative to the cartridge in the direction of the dispensing opening, whereby the highly viscous product can be dispensed through the cartridge opening and the housing opening,
• a spring element disposed between the inner side of the housing and the cartridge, the spring element having an extended position and a compressed position, wherein axial movement of the housing relative to the cartridge to dispense the highly viscous product moves the spring from the extended position toward the compressed position and spring element movement toward the extended position biases the housing toward a starting position,
• at least one engaging element formed on the inner side of the housing and a row of engaging recesses is formed on the piston, wherein both the engaging element and the engaging recesses are arranged outside of the receiving space, the engaging element engageable into one engaging recess with an actuation of the metering device, so that, movement of the housing relative to the cartridge provides movement of the piston relative to the cartridge and thus a dispensing of the highly viscous product from the metering device, and after an actuation of the metering device, the spring element biases the housing into the starting position during which the engaging element moves from the engaging recess into a neighboring engaging recess.