Claims for Patent: 9,687,611

Summary for Patent: 9,687,611

Title:	Injection device with torsion spring and rotatable display
Abstract:	The present invention relates to an injection device comprising a torsion spring operatively connected to a dose setting member being adapted to set a dose to be ejected from the injection device. A rotatably mounted display member adapted to display the dose to be ejected in accordance with a setting of the dose setting member is also provided. The rotatably mounted display member is adapted to be rotated over an angle corresponding to at least one revolution of the display member. The display member may be implemented as a dose indicator barrel having numerals arranged along a helical path on an outer surface thereof, or alternatively, as a counting device having two or more display wheels having numerals arranged on an outer surface thereof.
Inventor(s):	Moeller; Claus Schmidt (Fredensborg, DK), Markussen; Tom Hede (Bagsvaerd, DK), Enggaard; Christian Peter (Vejby, DK)
Assignee:	Novo Nordisk A/S (Bagsvaerd, DK)
Application Number:	14/167,558
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 9,687,611
Patent Claims:	1. An injection device comprising: a torsion spring (12) operatively connected to a dose setting member (1), the dose setting member (1) being adapted to set a dose to be ejected from the injection device, the torsion spring storing energy necessary to drive a dose of medication from the injection device, wherein energy is accumulated in the spring during a dose setting operation, and a rotatably mounted display member adapted to display the dose to be ejected from the injection device in accordance with a setting of the dose setting member (1), the rotatably mounted display member being rotatable over an angle corresponding to at least one revolution of the display member, wherein the display member is a barrel that is threadedly engaged with a device housing and wherein the barrel moves axially and in a proximal direction during the setting of a dose and moves distally during injection of a dose and wherein the barrel rotates toward a zero position during injection. 2. An injection device according to claim 1, wherein the display member is adapted to be moved between two end positions, said two end positions defining an operation range of the display member, said operation range being associated with a substantially linear working range of the torsion spring. 3. An injection device according to claim 1, wherein the display member comprises a dose indicator barrel (9) having numerals arranged along a helical path on an outer surface thereof. 4. An injection device according to claim 1, wherein the display member comprises a counting device having two or more display wheels having numerals arranged on an outer surface thereof. 5. An injection device according to claim 2, further comprising: a housing (5), a piston rod (2) having a threaded outer surface with a drive track (7) arranged in a longitudinal direction of said outer surface, wherein the dose setting member (1) is rotatably mounted and defines a passage for the piston rod (2), the dose setting member (1) further having a guiding track (11) arranged on an inner surface thereof, a rotatable drive member (6) being adapted to at least partly engage with at least part of the drive track (7) of the piston rod (2) so as to drive the piston rod, wherein the dose indicator barrel (9) has a part engaging at least part of the guiding track (11) of the dose setting member (1), the dose setting member (1) and the dose indicator barrel (9) being movable in relation to each other, the dose indicator barrel (9) further having a threaded outer surface (8) cooperating with a threaded inner portion (10) of the housing (5) whereby the dose indicator barrel (9) undergoes a combined translational and rotational movement in relation to the housing (5) upon rotation of the dose setting member (1), and wherein the injection device has a threaded portion (3) cooperating with the threaded outer surface of the piston rod (2) so that rotation of the piston rod (2) relative to the housing (5) results in a longitudinal movement of the piston rod (2). 6. An injection device according to claim 1, further comprising a threaded piston rod that moves distally during injection of a dose and a release that releases energy from the spring, the energy from the spring driving a dose from the injection device. 7. An injection device according to claim 5, wherein the drive member (6) is adapted to be connected to the dose setting member (1) via a ratchet (13). 8. An injection device according to claim 5, wherein the torsion spring (12) is arranged between the housing (5) and the dose setting member (1) in such a way that when the dose setting member (1) is rotated around the piston rod (2), the torsion spring (12) is strained. 9. An injection device according to claim 8, wherein the torsion spring (12) is a helical spring which extends coaxially with the piston rod (2). 10. An injection device according to claim 5, further comprising a locking member (4) adapted to fixate the piston rod (2) in such a way that no relative rotation between of the piston rod (2) and the housing (5) is possible when the locking member (4) is in its locking position. 11. An injection device according to claim 10, further comprising a release button adapted to release the locking member (4) from its locking position. 12. An injection device according to claim 11, wherein the release button is positioned in the distal half of the length of the injection device. 13. An injection device according to claim 5, further comprising a stopping member for defining an outer position of the dose indicator barrel (9), the outer position of the dose indicator barrel (9) corresponding to a maximum obtainable dose. 14. An injection pen comprising: a housing; a dose setting member for setting a dose, the dose setting member mounted to the housing so that it may rotate relative to the housing, the dose setting member being capable of rotated in two directions, one direction to increase the size of a dose and another to decrease the size of the dose; a dose indicator barrel having a helical scale, wherein the dose indicator barrel rotates when the dose setting member is rotated and is capable of rotating over more than one revolution; wherein the dose indicator barrel moves axially relative to both the housing the dose setting member when setting a dose; a torsion spring that store energy when a user rotates the dose setting member to set a dose, the torsion spring supplying the energy to drive a dose of medication from the injection pen; and a release button; wherein when the release button is activated by the user, the release button causes the torsion spring to drive the set dose from the injection pen and the dose indicator barrel rotates during injection back to a zero position. 15. An injection device comprising: a housing (5) with an inner surface provided with threads (10), a dose setting member (1) adapted to set a dose to be ejected from the injection device, a piston rod (2) having a threaded outer surface with a track (7) arranged in a longitudinal direction of its outer surface, a rotatable drive member (6) that engages with the track (7) or with the threaded outer surface of the piston rod to drive the piston rod (2), a torsion spring (12) for accumulating energy that is releasable to rotate the drive member (6) whereby the piston rod moves in the distal direction of the injection device to eject the set dose automatically, wherein, a rotatably mounted display member is threadedly engaged with the threads (10) of the housing (5) and operatively connected with the dose setting member (1) such that when the dose setting member (1) is rotated in order to set a dose, the display member rotates with the dose setting member (1) causing the display member to be axially displaced relative to the housing (5) and is adapted to display the dose to be ejected from the injection device in accordance with a setting of the dose setting member (1), the rotatably mounted display member is rotatable over an angle corresponding to at least one revolution, and the display member further returns to return to zero during ejection.