CONTROLLING A MOTOR OF AN INJECTION DEVICE

• US 20130204224A1
• Filed: 03/15/2011
• Published: 08/08/2013
• Est. Priority Date: 03/16/2010
• Status: Active Grant

• Current Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Original Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Inventors: Mller-Pathle, Stephan, Nessel, Christian, Eissengarthen, Christoph, Durrani, Navid
• Granted Patent: US 8,834,413 B2
• Time in Patent Office: Days
• US Class Current: 604/506
• CPC Class Codes: A61M 2005/31588 electrically driven
• CPC Class Codes: A61M 2205/332 Force measuring means
• CPC Class Codes: A61M 2205/8212 with means or measures taken for minimising energy consumption
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: A61M 5/20 Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically A61M5/142 , A61M5/46 take precedence; hypodermic projectiles F42B12/54
• CPC Class Codes: A61M 5/31525 Dosing burettes, pipettes B01L3/02
• CPC Class Codes: A61M 5/31546 Electrically operated dose setting, e.g. input via touch screen or plus/minus buttons

Abstract

In order to improve the energy efficiency of an injection device 100, a current is caused to be applied to a motor 113 of the injection device 100, which is related to a signal from a force sensor 115. The signal represents a force that is applied by the motor 113 to a plunger 122 of a cartridge 121.

Claims

1. A method comprising:

receiving a signal from a force sensor, the signal representing a force that is applied by a motor of an injection device to a plunger of a cartridge; and

causing a current that is required to enable the motor to apply the force represented by the signal from the force sensor to the plunger, incremented by a predetermined value, to be applied to the motor.

2. The method according to claim 1, wherein the predetermined value is a predetermined fixed value.

3. The method according to claim 1, wherein the predetermined value is a predetermined fraction of the represented force.

4. The method according to claim 1, wherein the motor is stepper motor.

5. The method according to claim 1, comprising measuring the force that is applied by the motor to the plunger of a cartridge by means of a force sensor that is integrated in the plunger.

6. The method according to claim 1, wherein the motor is configured to apply a force to the plunger by means of a piston rod, the method further comprising measuring the force that is applied by the motor to the plunger by means of a force sensor that is one of:

integrated in the piston rod; and

arranged between the piston rod and the plunger.

7. The method according to claim 1, wherein the force sensor is one of a force sensitive resistor, a quantum tunneling composite sensor and a strain gauge.

8. An apparatus comprising a controller,

the controller being configured to receive a signal from a force sensor, the signal representing a force that is applied by a motor of an injection device to a plunger of a cartridge;

and

the controller being configured to cause a current that is required to enable the motor to apply the force represented by the signal from the force sensor to the plunger, incremented by a predetermined value, to be applied to the motor.

9. The apparatus according to claim 8, wherein the predetermined value is a predetermined fixed value.

10. The apparatus according to claim 8, wherein the predetermined value is a predetermined fraction of the represented force.

11. The apparatus according to claim 8, wherein the motor is a stepper motor.

12. The apparatus according to claim 8, comprising the cartridge with the plunger, wherein the force sensor is integrated in the plunger and configured to measure the force that is applied by the motor to the plunger.

13. The apparatus according to claim 8, comprising the force sensor, the motor and a piston rod, the motor being configured to apply a force to the plunger by means of the piston rod, and the force sensor being configured to measure the force that is applied by the motor to the plunger, wherein the force sensor is one of:

integrated in the piston rod;

arranged between the piston rod and the plunger;

arranged between the piston rod and the motor; and

arranged between a cartridge holder holding the cartridge and another part of the apparatus.

14. The apparatus according to claim 8, wherein the force sensor is one of a force sensitive resistor, a quantum tunneling composite sensor and a strain gauge.

15. The apparatus according to claim 8, comprising the force sensor, the motor, the plunger and the cartridge.

16. The apparatus according to claim 8, wherein the apparatus is an injection device or an integrated circuit for an injection device.

17. A computer program configured to cause a processor executing the computer program to perform the following actions:

receiving a signal from a force sensor, the signal representing a force that is applied by a motor of an injection device to a plunger of a cartridge; and

causing a current that is required to enable the motor to apply the force represented by the signal from the force sensor to the plunger, incremented by a predetermined value, to be applied to the motor.

18. A computer readable medium encrypted with the computer program according to claim 17.

19. An apparatus comprising,

means for receiving a signal from a force sensor, the signal representing a force that is applied by a motor of an injection device to a plunger of a cartridge;

and

means for causing a current that is required to enable the motor to apply the force represented by the signal from the force sensor to the plunger, incremented by a predetermined value, to be applied to the motor.