Claims for Patent: 9,486,588

Summary for Patent: 9,486,588

Title:	Automatic injection device with reset feature
Abstract:	The present invention relates to a dose setting and expelling device comprising a drive member and a dose setting mechanism which simultaneously sets a given dose and stores the energy necessary for a subsequently driving the drive member in order to expel a dose of medicine from an injection device. According to the invention the dose setting mechanism allows adjustment in both directions, such that a given set dose can be reduced or cancelled by reversing the input motion, typically by rotating a setting member backwardly, this in contrast to the known devices which either requires an additional release mechanism or which cannot be reversed at all.
Inventor(s):	Enggaard; Christian Peter (Vejby, DK)
Assignee:	Novo Nordisk A/S (Bagsvaerd, DK)
Application Number:	14/168,700
Patent Claims:	1. An injection device for injecting medication from a cartridge, the device comprising: a housing, a drive member adapted to expel a dose of fluid from the reservoir, an elastic element comprising a torsion spring for storing and providing energy rotationally, a dose setting mechanism that cooperates with the elastic element, the dose setting mechanism being rotatable in a dose setting manner consisting of rotating the dose setting mechanism in a first direction to a selected set position, against a bias of the elastic element, wherein rotation of the dose setting mechanism stores energy in the elastic element for later use in expelling a drug from the reservoir, and in a second manner to reduce the size of the set dose, when necessary, the second manner consisting solely of rotating the dose setting mechanism in a second direction opposite the first direction to selectively adjust the set position to reduce the size of the set dose without expelling medication from the device, a releaseable latch adapted to retain the dose setting mechanism in the set position against the bias of the elastic element, wherein release of the latch causes the dose setting assembly to drive the drive member to thereby expel a set dose from a fluid-filled reservoir when the dose setting mechanism is used in combination therewith, the force for expelling the set dose being provided by the elastic element, wherein numbers are printed on an external surface disposed on the dose setting mechanism so that only a portion of the numbers are viewable through a window (17) on the housing during the setting of a dose, reduction of the size of a set dose, and expulsion of a dose from the fluid-filled reservoir. 2. An injection syringe for apportioning and injecting multiple doses of medication from a drug containing reservoir the injection syringe, the injection syringe comprising: a housing, a dose setting knob that is rotatable in two directions, a dose indicator having a helically arranged scale of numbers, a window on the housing for displaying at least one of the helically arranged numbers, a latch, an elastic energy storing member for storing a sufficient amount of energy to expel a set dose of medication, the elastic energy storing member storing a force that induce a rotational motion between two threaded components to create an axial movement of a member that transfers force to the drug containing reservoir, wherein the dose setting knob is manipulatable in a manner to set and selectively reduce the size of a set dose, when necessary, the manner consisting of rotating the dose setting knob in a first direction to set a dose, wherein rotation of the dose setting knob in the first direction stores energy in the elastic energy storing member, wherein the dose setting knob is freely rotatable in an opposite direction without the need for additional operations by a user, wherein rotation of the dose setting member in the opposite direction acts to reduce the size of the set dose without expelling medication, thereby allowing the user to selectively adjust the set dose downward without expelling medication, wherein when the latch is actuated it causes release of energy from the elastic energy storing member and wherein the released energy from the elastic energy storing member is transferred to a reservoir containing medication thereby expelling medication from the reservoir, wherein during the expelling of medication as the dose indicator rotates toward a zero position, which is the position that the scale was in prior to setting a dose, and wherein the rotation of the scale of numbers relative to the window is visible in the window during setting, reducing and the expelling of a dose of medication and wherein only a portion of the numbers are visible in the window at any one time. 3. The injection syringe of claim 2, wherein the elastic energy storing member is a torsion spring. 4. A dose setting and ejecting mechanism for use in combination with an injection device comprising a fluid-filled reservoir and a drive member having an external thread that engages an axially fixed component within the device having an internal thread, wherein the drive member is adapted to expel a dose of fluid from the reservoir, the dose setting and ejecting mechanism being adapted for repetitive injection of individually set doses of fluid from the reservoir, the dose setting and injecting mechanism comprising: a housing, a spring mounted in the housing, wherein the spring acts to store a torsional force for use in creating relative rotational motion between the drive member and the axially fixed component, a dose setting assembly mounted in the housing and connected to the spring, the dose setting assembly comprising a dose setting member being rotatable in a manner to set and adjust the size of a dose, the manner consisting of rotating the dose setting member in a first rotational direction to set the size of the dose and merely rotating the member in a second and opposite direction to reduce the size of the dose, when dose size reduction is necessary, wherein when the dose setting member is rotated in the second direction to reduce the size of a set dose, no drug is expelled from the device, wherein selectively reducing the size of the set dose consists solely of rotating the dose setting member in a second direction opposite that of the first direction a first direction and wherein rotating in the first direction is against the bias of the spring and results in the storage of energy in the spring for later use in expelling a drug from the reservoir, a releaseable latch adapted to retain the dose setting member in the set position against the bias of the spring, wherein release of the latch causes the spring in the dose setting assembly to drive the drive member to thereby expel a set dose from a fluid-filled reservoir in the injection device when the dose setting assembly is used in combination therewith, the force for expelling the set dose being provided by the spring, wherein release of the latch causes the spring to induce a relative rotational motion between the drive member and the axially fixed component having the internal thread thereby driving the drive member in a distal direction, and wherein numbers are printed along a helical line to form a scale on an external surface of a rotatable skirt so that only a portion of the numbers are viewable through a window in the housing during the setting of a dose, during dose size reduction without explusion and during expulsion of a dose during injection from the fluid-filled reservoir, when the skirt rotates. 5. The dose setting and ejecting mechanism of claim 4, wherein the dose setting and ejecting mechanism is integral to a medication delivery device comprising a cartridge of medication used to treat diabetes. 6. The dose setting and ejecting mechanism of claim 4, wherein the dose setting and ejecting mechanism is integral to a medication delivery device comprising a cartridge of medication used to treat a condition that requires self injections. 7. The injection syringe of claim 1, further comprising a threaded engagement between the drive member and the dose setting mechanism. 8. The injection syringe of claim 2, further comprising piston rod, and a threaded engagement between the piston rod and the dose indicator. 9. The dose setting and ejecting mechanism of claim 4, further comprising a threaded engagement between the drive member and the rotatable skirt.