Medicament delivery device

1. A medicament delivery device, comprising:

a housing having a proximal end and a distal end;

a hollow piston plunger within the housing;

a telescopic dose drum concentrically arranged between the housing and the piston plunger, the dose drum being bidirectional movable in relation to the housing and in relation to the piston plunger when setting a dose and delivering a dose;

a piston plunger driver configured to drive the piston plunger toward the proximal end, comprising:

a hollow drive drum sleeve movably arranged within the piston plunger and fixedly connected to the dose drum, wherein the drive drum sleeve and piston plunger are releasably coupled to each other;

a resilient spinning element having a longitudinal rod movably arranged within the drive drum sleeve, wherein the rod and drive drum sleeve are releasably coupleable to each other such that after a dose is set, axial movement of the resilient spinning element toward the proximal end forces the rod and drive drum sleeve to couple and thereby the drive drum sleeve and piston plunger to couple, whereby the piston plunger and dose drum are displaced toward the proximal end for delivering the set dose, and such that after the set dose is delivered, axial movement of the resilient spinning element toward the distal end forces the rod and drive drum sleeve to uncouple and thereby the drive drum sleeve and piston plunger to uncouple for setting a new dose;

a stop body connected to the piston plunger such that the stop body is rotatable but not slidable in relation to the piston plunger; and

a stop member connected to the dose drum, wherein the stop member and stop body are configured to interact when the set dose equals a remaining dose in a medicament container such that rotation of the dose drum is inhibited.

2. The medicament delivery device of claim 1 , wherein the stop body is ring-shaped having at least one protrusion, rib, or ledge on its outer surface.

3. The medicament delivery device of claim 1 , wherein the stop body is ring-shaped having at least one protrusion, rib, or ledge on its outer surface.

4. The medicament delivery device of claim 1 , wherein the dose drum includes a first distal part and a second proximal part, the parts being slidable relative to each other.

5. The medicament delivery device of claim 4 , wherein the second proximal part is a tube-shaped body comprising at least one longitudinally extending groove on in its inner surface, and the stop member is an end surface of the at least one groove.

6. The medicament delivery device of claim 4 , wherein the first distal part comprises at its distal end a dose setting knob configured to be grasped by a user for setting a dose when being rotated in a first direction.

7. The medicament delivery device of claim 6 , wherein the dose setting knob is connected with a first part of the dose drum at its distal end, whereby the first part of the dose drum is configured to move rotationally and distally in the first direction relative to the housing during dose setting by the dose setting knob.

8. The medicament delivery device of claim 1 , further comprising a medicament container holder configured to receive a medicament container.

9. The medicament delivery device of claim 1 , wherein part of an outer circumferential surface of the piston plunger is threaded.

10. The medicament delivery device of claim 1 , further comprising a unidirectional device configured to prevent movement of the piston plunger in a distal direction during setting a dose.

11. The medicament delivery device of claim 1 , wherein the medicament deliver device is an injection device.

12. The medicament device of claim 11 , wherein the injection device is a pen injector.