Injection device with a capacitive proximity sensor

• US 10,130,763 B2
• Filed: 03/17/2015
• Issued: 11/20/2018
• Est. Priority Date: 01/31/2006
• Status: Active Grant

• Current Assignee: Ares Trading SA (Merck & Co., Inc.)
• Original Assignee: Ares Trading SA (Merck & Co., Inc.)
• Inventors: Lauchard, Gerhard, Reindl, Martin, Guggenberger, Claudia-Carolin
• Primary Examiner(s): Price, Nathan R
• Assistant Examiner(s): Snyder, Melissa A
• Application Number:
  US14/660,824
• Publication Number:
  US 20150190575A1
• Time in Patent Office: 1,344 Days
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/208 Release is possible only when device is pushed against the skin, e.g. using a trigger which is blocked or inactive when the device is not pushed against the skin
• CPC Class Codes: A61M 2205/13 with means for the detection of operative contact with patient, e.g. lip sensor
• 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• CPC Class Codes: A61M 5/322 Retractable needles, i.e. disconnected from and withdrawn into the syringe barrel by the piston devices for protecting guide needles in combination with catheters A61M25/0612
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes

Abstract

An injection device for injecting medication to a patient, comprising a surface (5) having a through hole (3) for passage of a needle, is characterised by further comprising a capacitive proximity sensor (12, 13, 30) for detecting proximity or contact of human skin to/with said surface (5).

Claims

1. Injection device for injecting medication to a patient, comprising:

a surface having a through hole for passage of a needle; and

a capacitive proximity sensor configured to detect proximity or contact of human skin to/with said surface, wherein said capacitive proximity sensor includes a first electrode, a second electrode defining a capacitance with said first electrode and a circuit configured to detect a change in said capacitance due to the proximity of human skin to the sensor, and in that the second electrode has an elongate shape, is disposed within a U-shaped recess defined by the first electrode and is substantially parallel to a straight side of the first electrode formed by the U-shaped recess.

2. Injection device according to claim 1, further comprising a control unit configured to allow injection of medication only when detection by said sensor occurs.

3. Injection device according to claim 2, further comprising a mechanism configured to move said needle between a retracted position, inside said device, and an operating position, in which said needle protrudes from said through hole, said control unit configured to allow said mechanism to move said needle from said retracted position to said operating position only when detection by said sensor occurs.

4. Injection device according to claim 1, wherein said capacitive proximity sensor is adjacent to said through hole.

5. Injection device according to claim 1, wherein said first and second electrodes are substantially coplanar and disposed in a plane parallel to said surface.

6. Injection device according to claim 5, wherein said first and second electrodes are disposed on an internal surface of an insulating element, said insulating element having an external surface which defines at least part of said surface having said through hole.

7. Injection device according to claim 1, wherein said first electrode is larger than said second electrode.

8. Injection device according to claims 1, wherein said circuit configured to detect a change in said capacitance comprises a first electronic circuit which delivers a periodic signal to said first electrode.

9. Injection device according to claim 8, wherein said first electronic circuit is a timer circuit having an output coupled with said first electrode, a triggering input and a threshold input, said triggering and threshold inputs both coupled with said second electrode .

10. Injection device according to claim 8 , wherein said frequency of said periodic signal depends on said capacitance, and said circuit configured to detect a change in said capacitance further comprises a second electronic circuit configured to detect a change in said frequency based on the proximity of human skin to said sensor.

11. Injection device according to claim 1, further comprising a compensation electrode configured to limit the electric field generated by said first and second electrodes to a determined area.

12. Injection device according to claim 11, wherein said compensation electrode is disposed in a plane parallel to a plane defined by said first and second electrodes, is coupled with said second electrode, and has a shape which substantially corresponds to the contour of said first electrode.

13. Injection device according to claim 1, wherein the first electrode surrounds, at least partly, the second electrode.