Automatic drug delivery device

An automatic drug delivery device for dispensing a fluid product, the automatic drug delivery device comprising:

• (a) a longitudinal housing extending along a longitudinal axis and having a proximal end close to a dispensing site, a distal end opposite to the proximal end, and a hollow interior;
• (b) a removable cap mountable to the proximal end of the housing;
• (c) a first syringe assembly arranged in a mounting position inside the housing and having a hollow syringe body and an injection needle formed with the hollow syringe body including the fluid product, the first syringe assembly having a first diameter;
• (d) a drive mechanism configured to be triggered by a trigger element in order to initiate dispensing of the fluid product;
• and
• (e) a first syringe holder;
• wherein the drive mechanism is operatively coupled with a safety shield movable within the longitudinal housing,
• wherein the safety shield is biased into a proximal position in which the safety shield protrudes out of the proximal end of the longitudinal housing in order to cover a needle tip of the injection needle, and wherein the safety shield is movable into a distal position in which the injection needle is exposed for injection;
• wherein the longitudinal housing provides an inner receiving component fixed thereto for receiving the first syringe holder and providing a predetermined radial and axial position of the first syringe holder within the longitudinal housing;
• wherein the first syringe assembly is received within the longitudinal housing by the first syringe holder, wherein the first syringe holder provides an interface between the longitudinal housing and the first syringe assembly;
• and
• wherein the receiving component is sized and configured to receive a second syringe holder and a second syringe assembly, the second syringe assembly having a second diameter different from the first diameter, wherein the drive mechanism includes a plunger biased by a drive spring in a proximal direction, wherein the plunger includes a plurality of retaining slots at different axial positions, wherein the drive mechanism is configured to retain the plunger in an initial position via engagement of a radial inward projection with at least one retaining slot of the plurality of retaining slots, wherein the radial inward projection is configured to disengage the at least one retaining slot of the plurality of retaining slots in response to triggering of the drive mechanism by the trigger element.

An automatic drug delivery device for dispensing a fluid product, the automatic drug delivery device comprising:

• (a) a longitudinal housing extending along a longitudinal axis and having a proximal end close to a dispensing site, a distal end opposite to the proximal end, and a hollow interior;
• (b) a removable cap mountable to the proximal end of the housing;
• (c) a first syringe assembly arranged in a mounting position inside the housing and having a hollow syringe body and an injection needle formed with the hollow syringe body including the fluid product, the first syringe assembly having a first diameter;
• (d) a safety shield movable within the longitudinal housing, wherein the safety shield is biased into a proximal position in which the safety shield protrudes out of the proximal end of the longitudinal housing in order to cover a needle tip of the injection needle, and wherein the safety shield is movable into a distal position in which the injection needle is exposed for injection;
• (e) a drive mechanism configured to be triggered by a trigger element in order to initiate dispensing of the fluid product, wherein the drive mechanism is operatively coupled with the safety shield, wherein the drive mechanism includes a plunger biased by a drive spring in a proximal direction, wherein the plunger includes a plurality of through holes at different axial positions, wherein the drive mechanism is configured to retain the plunger in an initial position via engagement of a radial inward projection with at least one through hole of the plurality of through holes wherein the radial inward projection is configured to be disengaged from each through hole of the plurality of through holes during dispensing of the fluid product;
• (f) a first syringe holder, wherein the first syringe assembly is received within the longitudinal housing by the first syringe holder, wherein the first syringe holder provides an interface between the longitudinal housing and the first syringe assembly;
• and
• (g) an inner receiving component fixed to the longitudinal housing for receiving the first syringe holder and providing a predetermined radial and axial position of the first syringe holder within the longitudinal housing, wherein the receiving component is sized and configured to receive a second syringe holder and a second syringe assembly, the second syringe assembly having a second diameter different from the first diameter.