Device for dispensing an injectable product in doses

Abstract

A device for dispensing a product in doses including a casing element, a dosing device shiftable relative to the casing element in a dispensing direction, a setting device for setting the position of the dosing device, and a restoring element for returning the dosing device to a starting position, wherein a movement of the dosing device in the dispensing direction charges the restoring element.

1 . A device for dispensing a product in doses comprising:
 a casing element comprising a front dispensing end and a rear end;   an ampoule sleeve coupleable to the front dispensing end of the casing element;   a threaded nut for setting a dosage and arranged at the rear end of the casing;   a threaded rod arranged at least partly in an interior of the threaded nut, the threaded rod and the threaded nut comprising complementary threading such that in response to rotation of the threaded nut, the threaded rod moves in the axial direction, the threaded rod axially movable in one or more dosing procedure movements towards the front dispensing end;   a releasable locking arrangement for locking the threaded rod against rotation; and   a helical spring contained within the interior of the threaded nut and encircling the portion of the threaded rod arranged in the interior of the threaded nut, the helical spring acting between the threaded nut and the threaded rod, wherein the helical spring is in a relaxed state when the a rear end of the threaded rod is arranged in a starting position within the threaded nut and the threaded nut is proximate the rear end of the casing element, and the helical spring is biased when the rear end of the threaded rod is in a front position and the threaded nut is proximate the rear end of the casing element;   wherein, upon releasing the locking arrangement, the biased helical spring urges the threaded rod to rotate towards its starting position.   
   
   
       2 . The device as set forth in  claim 1 , further comprising another releasable locking arrangement for locking the threaded nut against rotation. 
   
   
       3 . The device as set forth in  claim 2 , wherein the another releasable locking arrangement comprises an axially movable engagement of the threaded nut with the casing element 
   
   
       4 . The device as set forth in  claim 2 , wherein said releasable locking arrangement and said another releasable locking arrangement are coupled such that in the starting position, the threaded nut can be rotated and the threaded rod is secured against rotation, and in the front position the threaded nut is secured against rotation and the threaded rod can be rotated. 
   
   
       5 . The device as set forth in  claim 1 , wherein the releasable locking arrangement comprises a pressure spring arranged at a front dispensing end of the casing element. 
   
   
       6 . The device as set forth in  claim 1 , wherein upon releasing the locking arrangement, the threaded rod rotates towards its starting position to a selected position. 
   
   
       7 . The device as set forth in  claim 1 , wherein upon releasing the locking arrangement, the threaded rod rotates to its starting position. 
   
   
       8 . The device as set forth in  claim 1 , further comprising a coupling device for releasably receiving the ampoule sleeve, wherein at least one of the releasable locking arrangement and the another releasable locking arrangement can be established or released by said coupling device.