Details for Patent: RE46363

Title:	Dial-down mechanism for wind-up pen
Abstract:	The present invention relates to a dial-down mechanism for an injection device comprising a torsion spring for assisting injection of a dose of medicament from the injection device, the dial-down mechanism comprising dial-up cam arranged to receive and engage with a dial-up key, wherein the dial-up cam and the dial-up key are adapted to, upon rotation of a dose setting member in a first direction, cooperate to strain the torsion spring of the injection device, and a dial-down cam arranged to receive and engage with a dial-down key, wherein the dial-down cam and the dial-down key are adapted to, upon rotation of the dose setting member in a second direction, cooperate to release the torsion spring of the injection device, the second rotation direction being opposite to the first rotation direction.
Inventor(s):	Moeller; Claus Schmidt (Fredensborg, DK), Enggaard; Christian Peter (Vejby, DK), Radmer; Bo (Hilleroed, DK), Markussen; Tom Hede (Bagsvaerd, DK)
Assignee:	Novo Nordisk A/S (Bagsvaerd, DK)
Filing Date:	Nov 27, 2013
Application Number:	14/091,774
Claims:	1. A dial-down mechanism for an injection device comprising a torsion spring (18) for assisting injection of a dose of medicament from the injection device, the dial-down mechanism comprising dial-up cam (15) arranged to receive and engage with a dial-up key (11), wherein the dial-up cam (15) and the dial-up key (11) are adapted to, upon rotation of a dose setting member in a first direction, cooperate to strain the torsion spring (18) of the injection device, and a dial-down cam (16) arranged to receive and engage with a dial-down key (12), wherein the dial-down cam (16) and the dial-down key (12) are adapted to, upon rotation of the dose setting member in a second direction, cooperate to release the torsion spring (18) of the injection device, the second rotation direction being opposite to the first rotation direction, wherein the dial-up and dial-down cams form part of regions of the same track, further comprising an arm wherein the dial-up and dial-down keys are both located on the same arm, said keys being adapted to engage and cooperate with dial-up and dial-down cams of the same track. 2. A dial-down mechanism according to claim 1, wherein the dial-up cam (15) forms part of a curved track. 3. A dial-down mechanism according to claim 2, wherein the curved dial-up cam (15) forms part of a circular, elliptical or parabolic track. 4. A dial-down mechanism according to claim 1 comprising a first and a second dial-up cam. 5. A dial-down mechanism according to claim 4 comprising a first and a second dial-up key, wherein the first dial-up key is adapted to engage and cooperate with the first dial-up cam, and wherein the second dial-up key is adapted to engage and cooperate with the second dial-up cam. 6. A dial-down mechanism according to claim 1, wherein the dial-down cam (16) forms part of a V-shaped track. 7. A dial-down mechanism according to claim 1 comprising a first and a second dial-down cam. 8. A dial-down mechanism according to claim 7 comprising a first and a second dial-down key, wherein the first dial-down key is adapted to engage and cooperate with the first dial-down cam, and wherein the second dial-down key is adapted to engage and cooperate with the second dial-down cam. 9. A medication delivery device comprising a dial-down mechanism according to claim 1. 10. A medication delivery device according to claim 9, wherein the medication delivery device is a handheld medication injection pen. .Iadd.11. A method for using a wind up injection pen, the method comprising the steps of rotating a first element in a first direction, the direction being a dial up direction; causing a second element to be rotated in the same direction as the first element; straining a torsional spring; moving an arm that is in engagement with one edge to a neighboring edge, wherein when the arm is engaged with an edge it prevents the torsional spring from unwinding; rotating the first element in a second direction opposite the first direction; moving a pick-up key and radially lifting the arm out of engagement with an edge and when the arm is fully disengaged from an edge allowing the second rotatable element to rotate in the second direction and allowing the strain on the spring to be decreased..Iaddend.