US 10,376,641 B2
Automatic injection device for administering a fixed dose
Jürg Hirschel, Aarau (CH); Ulrich Moser, Heimiswil (CH); Markus Tschirren, Kirchberg (CH); and Patrick Vogt, Niederbipp (CH)
Assigned to TecPharma Licensing AG, Burgdorf (CH)
Filed by Jürg Hirschel, Aarau (CH); Ulrich Moser, Heimiswil (CH); Markus Tschirren, Kirchberg (CH); and Patrick Vogt, Niederbipp (CH)
Filed on Feb. 10, 2011, as Appl. No. 13/24,970.
Application 13/024,970 is a continuation of application No. PCT/CH2009/000267, filed on Jul. 31, 2009.
Claims priority of application No. 10 2008 037 310 (DE), filed on Aug. 11, 2008.
Prior Publication US 2011/0196339 A1, Aug. 11, 2011
Int. Cl. A61M 5/20 (2006.01); A61M 5/32 (2006.01)
CPC A61M 5/2033 (2013.01) [A61M 5/326 (2013.01); A61M 2005/2013 (2013.01); Y10T 29/49826 (2015.01)] 25 Claims
OG exemplary drawing
 
1. An injection device for administering a substance, comprising:
a housing;
a syringe fixedly mounted in the housing;
a plunger rod;
at least one retaining element for holding the plunger rod relative to the housing so the rod is not able to move;
a protective sleeve movable relative to the housing;
a needle fixedly mounted to the housing and surrounded by the protective sleeve;
a first spring; and
a second spring,
wherein when the protective sleeve is pushed back relative to the housing, against a force of the second spring, from a first position in which the needle is surrounded by the protective sleeve to a second position, the needle is exposed from the protective sleeve,
wherein when the protective sleeve is pushed against an injection surface, the protective sleeve moves to the second position such that insertion of the needle is effected,
wherein when the protective sleeve moves from the first position to the second position:
the at least one retaining element is released and the first spring pushes the plunger rod in a distal direction to initiate a dispensing operation, and
the second spring is compressed and pushes the protective sleeve in the distal direction,
wherein a first resilient element snaps in the housing and generates a first click indicating an end of the dispensing operation,
wherein, upon removal of the injection device from the injection surface and movement of the protective sleeve by the second spring into a front-most position, a second resilient element snaps over an end of a locking element and generates a second click, indicating a locked state of the injection device, and
wherein in the locked state, the protective sleeve is blocked from moving.