Medication dispensing device

• US 5,383,865 A
• Filed: 03/15/1993
• Issued: 01/24/1995
• Est. Priority Date: 03/15/1993
• Status: Expired due to Term

• Current Assignee: Eli Lilly and Company
• Original Assignee: Eli Lilly and Company
• Inventors: Michel, Peter
• Primary Examiner(s): Rosenbaum, C. Fred
• Assistant Examiner(s): ELGART, VANITHA M
• Application Number:
  US08/031,595
• Time in Patent Office: 680 Days
• Field of Search: 604/232, 604/218, 604/220-222, 604/224, 604/187, 604/228-229, 604/206, 604/209, 604/236, 604/248, 604/71, 604/72, 604/208, 604/186, 604/65-66, 604/210-211 , 604/260, 604/404, 604/207, 221/2, 221/3, 222/39, 222/41, 222/46, 222/402.13, 222/386, 222/309, 222/390, 222/391
• US Class Current: 604/232
• CPC Class Codes: A61M 2005/3126 Specific display means related to dosing
• CPC Class Codes: A61M 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/31535 Means improving security or handling thereof, e.g. blocking means, means preventing insufficient dosing, means allowing correction of overset dose
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• CPC Class Codes: A61M 5/31556 Accuracy improving means
• CPC Class Codes: A61M 5/3158 performed by axially moving actuator operated by user, e.g. an injection button

Abstract

A medication dispensing device comprising a cartridge for containing an injectable product therein and an injector attached to the cartridge. The injector includes a drive mechanism comprising a dosage sleeve having a dosage knob at the proximal end thereof and a threaded rod coupled to the sleeve and axially advanceable into the cartridge upon clockwise rotation of the knob for dialing up a desired dosage to be injected. A ratchet mechanism is disposed in the injector housing and includes a rotatable piece secured to the dosage sleeve for rotation therewith and a locking seat in engagement with the rotatable piece. The ratchet mechanism permits rotational movement of the sleeve in the clockwise direction only. A disengaging mechanism is secured to the housing of the LCD assembly and includes a pin that extends into and engages the rotatable piece of the ratchet mechanism such that axial movement of the pin causes corresponding axial movement of the stationary piece. Upon depressing the outer surface of the disengaging mechanism, the pin and the rotatable piece are moved axially away from the seat sufficiently enough to permit a user to rotate the dosage knob in a counterclockwise direction to accurately dial back an accidental overdose measurement without removing the cartridge from the injector.

Claims

1. A medication dispensing device, comprising:

a cartridge for containing and sealing an injectable product therein, said cartridge including a plunger therein; and

an injector attached to said cartridge and comprising a housing, a drive mechanism disposed in said housing and including a dosage sleeve having a knob at a proximal end of said dosage sleeve and a rod coupled to said sleeve such that upon rotation of said knob, said rod is axially advanceable a first distance to establish a set dosage of injectable product to be delivered without effecting delivery of the injectable product, a clutch mechanism disposed in said housing and comprising a rotatable piece that is secured to said dosage sleeve for rotation therewith and a locking seat in engagement with said rotatable piece and being configured to restrict rotation of said rotatable piece, and hence said dosage knob, to a first direction only, a disengaging mechanism for selectively disengaging said locking seat from said rotatable piece thereby permitting rotation of said dosage sleeve in a second and opposite direction while said cartridge is attached to said injector to reduce the first distance of axial advancement of said rod thereby reducing the set dosage of injectable product to be delivered, wherein said rod is axially advanceable a second distance upon axial force being applied to said knob to engage and axially advance said plunger to effect delivery of the set dosage of injectable product.

2. The device of claim 1, wherein said rotatable piece includes a grooved surface therein defining an adjacent lip, and said disengaging mechanism comprises a pin disposed in said grooved surface in such a manner that axial movement of said pin causes said pin to engage said lip, thereby causing axial movement of said rotatable piece away from said locking seat.

3. The device of claim 1, wherein said rotatable piece is generally tubular in shape and includes a spring therein for biasing said rotatable piece against said locking seat.

4. The device of claim 1, wherein a liquid crystal display (LCD) housing is secured to said injector housing and contains an LCD assembly therein including an integrated circuit, a contact for periodically inputting a signal to the circuit, and a display window for providing a visual display of the output delivered by the circuit, wherein the contact is configured to be periodically engaged by said dosage knob to cause a dosage indicia to appear in the display window.

5. The device of claim 4, wherein said disengaging mechanism is secured to said LCD housing and includes a pin extending through an opening in said injector housing and engaging said rotatable piece.

6. The device of claim 1, wherein said clutch mechanism is in the form of a ratchet device.

7. The device of claim 1, wherein the rod is advanceable by means of a threaded connection between said rod and said sleeve.

8. The device of claim 1, including a display means operatively connected to said sleeve for providing a visual dosage indication that increments-and decrements as said sleeve rotates respectively in the first and second directions.

9. The device of claim 1, wherein said disengaging mechanism includes a user actuated element that is connected to said clutch to disengage said seat and rotatable piece when said element is actuated.

10. The device of claim 9, wherein said user actuated element is slidable relative to said housing.

11. A medication dispensing device, comprising:

a cartridge for containing and sealing an injectable product therein, said cartridge including a plunger therein; and

injector means attached to said cartridge for delivering a desired dosage of product into a patient, said injector means including knob means for engagement by a user and a rod coupled to said knob means, said rod being axially advanceable with respect to said housing upon rotation of said knob means in a first direction, wherein said rod is advanceable a first distance to establish a set dosage of injectable product to be delivered without effecting delivery of the injectable product, clutch means in engagement with said rod for restricting rotation of said rod in a second and opposite direction; and

a clutch disengaging means for selectively disengaging said clutch means, thereby permitting rotation of said knob means in said second direction while said cartridge is attached to said injector means to cause said rod to move axially toward said injector means to reduce the first distance of axial advancement of said rod thereby reducing the set dosage of injectable product to be delivered, wherein said rod is axially advanceable a second distance upon axial force being applied to said knob means to engage and axially advance said plunger to effect delivery of the set dosage of injectable product.

12. The device of claim 11, including a digital display means operatively coupled to said knob means for providing a visual dosage indication that increments and decrements as said knob rotates respectively in the first and second directions.

13. The device of claim 11, wherein said rod is threadedly coupled to said knob means.

14. The device of claim 11, including means for disengaging said clutch means when the cartridge is removed from said injector.

15. An injector device for injecting a product contained in a cartridge attached to the injector, said cartridge including a plunger therein, comprising:

a housing;

a drive mechanism disposed in said housing and including a dosage device having a control knob and a rod coupled to said dosage device such that upon rotation of said knob, said rod is axially advanceable a first distance to establish a set dosage of injectable product to be delivered without effecting delivery of the injectable product;

a clutch mechanism disposed in said housing and comprising a rotatable piece that is connected to said dosage device for rotation therewith and a locking seat in engagement with said rotatable piece and being configured to restrict rotation of said rotatable piece, and hence said dosage knob, to a first direction only while the injector is attached to a cartridge; and

a disengaging mechanism for selectively disengaging said locking seat from said rotatable piece thereby permitting rotation of said dosage device in a second and opposite direction while the injector is attached to the cartridge to permit an overdose measurement to be dialed back to a desired dosage, wherein said rod is axially advanceable a second distance upon axial force being applied to said knob to engage and axially advance said plunger to effect delivery of the set dosage of injectable product.

16. In a medication dispensing device for measuring and injecting a desired dosage of injectable product into a patient, a method for reducing an excess dosage of measured product, the method comprising the steps of:

attaching a cartridge containing an injectable product therein to an injector including a dosage knob and an axially advanceable rod;

rotating the knob in a first direction only to cause the rod to axially advance into the cartridge a first distance to establish a set dosage of injectable product to be delivered without effecting delivery of the injectable product;

engaging a clutch-deactuating mechanism;

rotating the dosage knob in a second and opposite direction until the rod has been axially retracted within the cartridge a sufficient distance to reduce the set dosage to be injected; and

releasing the clutch-deactuating mechanism thereby preventing rotation of the dosage knob in the second direction while the cartridge is attached to the injector.