Pen-type injector having holding mechanism for medicament cartridge

1. An injection device for injection of a medicament from a medicament cartridge having a neck portion, the injection device comprising:

a main housing in which the medicament cartridge is releasably retained by first and second retaining means, the retaining means each being moveable between a first position in which the neck portion is engaged thereby to retain the medicament cartridge in the main housing and a second position which allows the medicament cartridge to be removed from the main housing;

spring means disposed between the first and second retaining means to urge the first and second retaining means toward the second position; and

a slider tab acting on each of the first and second retaining means to urge the first and second retaining means towards the first position.

2. An injection device according to claim 1 , wherein, the slider tab acts on an external face of each of the first and second retaining means.

3. An injection device according to claim 1 , wherein, the slider tab is slidably retained within a groove formed in the main housing.

4. An injection device according to claim 1 , wherein, the slider tab is adapted to engage the neck portion of the medicament cartridge.

5. An injection device according to claim 1 , wherein, the main housing includes an end stop to prevent movement of the first and second retaining means beyond the second position.

6. An injection device according to claim 1 , wherein, the first and second retaining means move radially about a common pivot point.