The present invention relates to a device for delivering a fixed dose or an adjustable dose of liquid medicament to a patient. Characterising for the present invention is that it is equipped with a planetary gear with the purpose of increasing the power needed to deliver liquid medicament out of this type of devices. On almost all of the devices of this type appearing on the market with the purpose of delivering a fixed dose or an adjustable dose of liquid medicament, the dose volume can be set in separated steps. With assistance of a planetary gear these steps, which each represent an increase of the volume of the medicament to be delivered, get smaller, which increases the possibility to set an optimum dose volume of the medicament. In its primary field of use the invention is intended to be used together with an injection needle. The invention facilitates to create high fluid pressure in the medicament and can be used to operate an inhaler or a needle free injector at the same time as the invention will keep a compact outside measurement.