Abstract: The present invention relates to a torsion spring based automatic injection device for expelling settable doses of a liquid drug. The spring mechanism of the injection device comprises a housing assembly and a dose setting assembly being rotatable relatively to the housing assembly and a torsion spring (1) encompassed there between such that the torsion spring (1) is strained when rotating the dose setting assembly relatively to the housing assembly. The torsion spring (1) is helically coiled having a longitudinal direction (X) and a number of consecutive windings wherein a distal winding (4) has a distal end (2) and a proximal winding (5) has a proximal end (3). Each of the winding has an outwardly pointing surface (6) together forming an outside surface of the torsion spring being parallel to the longitudinal direction (X).

Abstract: A push button connection for an injection device comprising a push button (10) and a driving part (20). The two parts of the push button connection are mounted to each other and is relatively rotatable to each other. In order to minimize the friction occurring between the push button and the driving part when relatively rotated forces are transmitted via a pivot bearing (18, 22). In order also to minimize the effect of forces appearing dislocated from the center line a number of radial bearings (13, 23; 14, 25) having a little friction diameter is provided.

Abstract: A skin retention device 10 for a medical jet-injection unit 20 having a contact face provided with adhesive 12 in the area surrounding and close to the injection opening(s) 11 of the nozzle 21 which ensures good contact between the nozzle 21 and the skin 30 of a subject in the area chosen for an injection. The injection force can be lowered dramatically. In case of two-stage jet-injections, the initial injection force can be lowered because the skin retention close to the injection point significantly reduces the energy consuming elastic expansion of the skin 30 in the injection area, and the second injection force can be lowered because of the high degree of fixed positioning of the injection opening of the nozzle 21 relative to the injection channel in the skin 30 made during the initial injection stage.

Abstract: A pressurized injection device comprises a mechanical loading mechanism comprising a double set of rackets (17,18) and ball bearings/pins running in a curved track (20) which enables a resilient element (7) to be pre-stressed by—twisting the two outer house parts of the device relative to each other back and forth. When twisted in one direction one set of rackets (17) engages the teeth of the piston rod (9) connected to the resilient element and when twisted in the opposite direction, the other set of rackets (18) engages same piston rod. The resilient element is set off to engage a plunger of a container holding a drug to be injected by pressing the release button (1), which can be secured by a safety switch.

Abstract: The invention provides a jet expelling assembly comprising a reservoir and an impulse chamber assembly. The impulse chamber assembly comprises a chamber portion defining a cavity having a general axis, a piston received in the cavity along the general axis and comprising a fluid inlet, thereby defining a variable-volume impulse chamber with an outlet nozzle. The inlet comprises a conduit adapted to slidably engage a reservoir outlet during relative movement therebetween. The chamber portion is arranged stationary relative to the reservoir, whereby expelling an amount of drug from the reservoir to the impulse chamber via the inlet causes the piston to move towards the reservoir, the impulse chamber thereby receiving the expelled amount of drug.

Abstract: A skin retention device 10 for a medical jet-injection unit 20 comprises a contact face provided with adhesive 12 in the area surrounding and close to the injection opening(s) 11 of the nozzle 21 which ensures god contact between the nozzle 21 and the skin 30 of a subject in the area chosen for an injection. Consequently the injection force can be lowered dramatically. In case of two-stage jet-injections, the initial injection force can be lowered because the skin retention close to the injection point significantly reduces the energy consuming elastic expansion of the skin 30 in the injection area, and the second injection force can be lowered because of the high degree of fixed positioning of the injection opening of the nozzle 21 relative to the injection channel in the skin 30 made during the initial injection stage. Thus a high degree of injection safety is achieved, minimizing the risk of whet shots, while skin lift and lower injection force decreases the risk of damage of the underlying tissue.

Abstract: A pressurised injection device comprises a mechanical loading mechanism comprising a double set of rackets (17,18) and ball bearings/pins running in a curved track (20) which enables a resilient element (7) to be pre-stressed by—twisting the two outer house parts of the device relative to each other back and forth. When twisted in one direction one set of rackets (17) engages the teeth of the piston rod (9) connected to the resilient element and when twisted in the opposite direction, the other set of rackets (18) engages same piston rod. The resilient element is set off to engage a plunger of a container holding a drug to be injected by pressing the release button (1), which can be secured by a safety switch.

Abstract: A push button connection for an injection device comprising a push button (10) and a driving part (20). The two parts of the push button connection are mounted to each other and is relatively rotatable to each other. In order to minimize the friction occurring between the push button and the driving part when relatively rotated forces are transmitted via a pivot bearing (18, 22). In order also to minimize the effect of forces appearing dislocated from the centre line a number of radial bearings (13, 23; 14, 25) having a little friction diameter is provided.

Abstract: A skin retention device 10 for a medical jet-injection unit 20 comprises a contact face provided with adhesive 12 in the area surrounding and close to the injection opening(s) 11 of the nozzle 21 which ensures god contact between the nozzle 21 and the skin 30 of a subject in the area chosen for an injection. Consequently the injection force can be lowered dramatically. In case of two-stage jet-injections, the initial injection force can be lowered because the skin retention close to the injection point significantly reduces the energy consuming elastic expansion of the skin 30 in the injection area, and the second injection force can be lowered because of the high degree of fixed positioning of the injection opening of the nozzle 21 relative to the injection channel in the skin 30 made during the initial injection stage. Thus a high degree of injection safety is achieved, minimizing the risk of whet shots, while skin lift and lower injection force decreases the risk of damage of the underlying tissue.

Abstract: A jet injection device comprises a medical jet unit (10), a medical drug dispensing unit (20) and an medical drug injection unit (30). The empty medical jet unit (10) is connected to the medical drug dispensing unit (20) and the plunger (11) inside the medical jet unit (10) snaps to the removable drug container (40) inside the medical drug dispensing unit (20), thereby creating fluid connection between the drug container (40) and chamber of the medical jet unit (10) via a hollow back needle.