PEN-TYPE DRUG INJECTION DEVICE WITH DOSE SETTING AND RE-SETTING MECHANISM
First Claim
1. Drive mechanism for an injection device, the mechanism comprising:
- a housing (4, 5;
104, 105),a dial member (6;
106),a torsion spring (12;
112) fixed between the housing (4, 5;
104, 105) and the dial member (6;
106) such that energy is accumulated in the torsion spring (12;
112) upon rotation of the dial member (6;
106) relative to the housing (4, 5;
104, 105),a drive member (8;
108) engaging a lead screw (9;
109),a first clutch (18;
118) rotationally coupling the drive member (8;
108) and the housing (4, 5;
104, 105) in a coupled state and allowing relative rotation between the drive member (8;
108) and the housing (4, 5;
104, 105) in a de-coupled state,a second clutch (19;
119) rotationally coupling the drive member (8;
108) and the dial member (6;
106) in a coupled state and allowing relative clockwise and anti-clockwise rotation between the drive member (8;
108) and the dial member (6;
106) in a de-coupled state,wherein the second clutch (19;
119) comprises a ratchet clicker with teeth (19a, 19b;
119a, 119b) having in the clockwise and the anti-clockwise direction different ramped tooth angles such that the teeth (19a, 19b;
119a, 119b) are allowed to override each other in the de-coupled state of the second clutch (19;
119) with a different resistance in the clockwise and the anti-clockwise direction.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention relates to a pen type drug injection device (1; 101) comprising a housing (4, 5; 104, 105), a dose dial member (6; 106), a torsion spring (12; 112) fixed between the housing and the dial member such that energy is accumulated in the torsion spring upon rotation of the dial member relative to the housing, a drive member (8; 108) engaging a lead screw (9; 109), a first clutch (18; 118) rotationally coupling the drive member (8; 108) and the housing in a coupled state and allowing relative rotation between the drive member and the housing in a de-coupled state, and a second clutch (19; 119) rotationally coupling the drive member and the dial member in a coupled state and allowing relative clockwise and anti-clockwise rotation between the drive member and the dial member in a de-coupled state. The second clutch comprises a ratchet clicker with teeth (19a, 19b; 119a, 119b) having in the clockwise and the anti-clockwise direction different ramped tooth angles such that the teeth are allowed to override each other in the de-coupled state of the second clutch with a different resistance in the clockwise and the anti-clockwise direction, such that a dose can be set and also corrected by the user thereby tensioning respectively relaxing the torsion spring.
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Citations
16 Claims
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1. Drive mechanism for an injection device, the mechanism comprising:
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a housing (4, 5;
104, 105),a dial member (6;
106),a torsion spring (12;
112) fixed between the housing (4, 5;
104, 105) and the dial member (6;
106) such that energy is accumulated in the torsion spring (12;
112) upon rotation of the dial member (6;
106) relative to the housing (4, 5;
104, 105),a drive member (8;
108) engaging a lead screw (9;
109),a first clutch (18;
118) rotationally coupling the drive member (8;
108) and the housing (4, 5;
104, 105) in a coupled state and allowing relative rotation between the drive member (8;
108) and the housing (4, 5;
104, 105) in a de-coupled state,a second clutch (19;
119) rotationally coupling the drive member (8;
108) and the dial member (6;
106) in a coupled state and allowing relative clockwise and anti-clockwise rotation between the drive member (8;
108) and the dial member (6;
106) in a de-coupled state,wherein the second clutch (19;
119) comprises a ratchet clicker with teeth (19a, 19b;
119a, 119b) having in the clockwise and the anti-clockwise direction different ramped tooth angles such that the teeth (19a, 19b;
119a, 119b) are allowed to override each other in the de-coupled state of the second clutch (19;
119) with a different resistance in the clockwise and the anti-clockwise direction.- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
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Specification