INJECTION DEVICE

• US 20130079728A1
• Filed: 11/21/2012
• Published: 03/28/2013
• Est. Priority Date: 06/16/2000
• Status: Active Grant

• Current Assignee: Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: Moeller, Claus Schmidt
• Granted Patent: US 9,022,991 B2
• Time in Patent Office: Days
• US Class Current: 604/211
• CPC Class Codes: A61M 2005/3152 including gearings to multiply or attenuate the piston displacing force
• CPC Class Codes: A61M 2205/581 by audible feedback
• 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 5/28 Syringe ampoules or carpules, i.e. ampoules or carpules provided with a needle
• CPC Class Codes: A61M 5/315 Pistons; Piston-rods; Guiding, blocking or restricting the movement of the rod or piston; Appliances on the rod for facilitating dosing ; Dosing mechanisms
• CPC Class Codes: A61M 5/31541 Means preventing setting of a dose beyond the amount remaining in the cartridge
• CPC Class Codes: A61M 5/3155 by rotational movement of dose setting member, e.g. during setting or filling of a syringe
• CPC Class Codes: A61M 5/31551 including axial movement of dose setting member
• CPC Class Codes: A61M 5/31558 using scaling up or down transmissions, e.g. gearbox
• CPC Class Codes: A61M 5/31575 using scaling up or down transmissions, e.g. gearbox
• CPC Class Codes: A61M 5/3158 performed by axially moving actuator operated by user, e.g. an injection button

Abstract

A medication dispensing device with a housing and a member wherein the member is moveable in a distal direction is useful in delivering medication to a patient. A fluid container can be used with the device and often has a moveable piston at one end and an outlet at the other. The member receives a force from a user and drives the piston in the distal direction to expel medication. A intermediate system is disposed between the member and the piston including a gear set that has a pinion in meshed engagement with a rack. The system allows the member to move a greater distance than the piston moves thereby increasing the force on the piston.

Claims

1. An dose setting and injection mechanism for an injection device, the mechanism comprising:

a. A threaded piston rod having a distal end for pressing medicine out of a cartridge and a proximal portion;

b. A nut element (13, 113) threadedly engaging the thread on the piston rod at the proximal portion of the piston rod;

c. A dose setting drum that rotates during the setting of a dose; and

d. a coupling ring (25) that moves axially and engage the dose setting drum during injection of medication and prevents rotation of the dose setting drum during injection but during dose setting provides a click sound when the dose setting drum is rotated, wherein the coupling ring moves axially during injecting of medication.

2. The mechanism of claim 1, wherein the piston rod is a non-rotating piston rod.

3. A dose setting and injection mechanism for an injection device, the mechanism comprising:

A tubular element (5) that is disposed concentrically with a housing, wherein the tubular element 5 has an outer thread 2 that engages an inner thread on a dose setting drum and wherein tubular element 5 further comprises a longitudinal recess 137 or alternatively a rib 28 that engages a complementary ridge or recess on a ring 25 so that the ring 25 can be displaced in an axial direction but also so that ring 25 cannot rotate.