LANCET DEVICE

• US 20080188883A1
• Filed: 01/11/2008
• Published: 08/07/2008
• Est. Priority Date: 07/13/2005
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Hoerauf, Christian, Deck, Frank, Storjohann, Jens, Jotter, Mathias, Rufer, Manfred, Hinrichs, Malte, Grunwald, Torsten, Berg, Hartmut
• Granted Patent: US 8,672,963 B2
• Time in Patent Office: Days
• US Class Current: 606/182
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150412 Pointed piercing elements, e.g. needles, lancets for piercing the skin blade-like piercing elements A61B5/150442
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/15107 Piercing being assisted by a triggering mechanism
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15123 comprising magnets or solenoids
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit
• CPC Class Codes: A61B 5/15194 fully automatically retracted, i.e. the retraction does not require a deliberate action by the user, e.g. by terminating the contact with the patient's skin

Abstract

The present invention relates to a lancet device, by which a lancet can be displaced along a piercing path for generating a piercing wound in a skin surface, in particular to obtain bodily fluid for diagnostic purposes, comprising a lancet drive having drive means to generate a drive force for a piercing movement of the lancet along the piercing path in the direction toward the skin surface. According to the present invention, the lancet drive comprises a magnet, by which a magnetic retention force oriented opposite to the drive force may be generated, and the lancet drive also comprises triggering means, by which the retention force may be reduced enough that the lancet is accelerated in the direction toward the skin surface under the effect of the drive force generated by the drive means. The present invention also relates to a method for generating a piercing wound, in which the drive spring is held in a tensioned state using a magnetic retention force oriented opposite to the drive force before the triggering of a piercing wound.

Claims

1. A lancet device, by which a lancet can be displaced along a piercing path to generate a piercing wound in a skin surface, in particular to obtain bodily fluid for diagnostic purposes, comprising

a lancet drive having drive means for generating a drive force for a piercing movement of the lancet along the piercing path in the direction toward the skin surface,

the lancet drive comprises a magnet, by which a magnetic retention force directed opposite to the drive force may be generated, and

the lancet drive also comprises triggering means, by which the retention force may be reduced enough that the lancet is accelerated in the direction toward the skin surface under the effect of the drive force generated by the drive means,

the drive means comprises a further permanent magnet which is situated with opposite polarity to the permanent magnet generating the retention force.

2. The lancet device according to claim 1, wherein the drive means comprises a drive spring, wherein the drive spring can be held in a tensioned state by the magnetic retention force.

3. The lancet device according to claim 2, wherein the drive spring is a coiled spring, which encloses a pushrod, which carries the lancet.

4. The lancet device according to claim 2, wherein the lancet drive comprises a restoring spring to generate a retraction movement of the lancet, during which the drive spring is tensioned again.

5. The lancet device claim 1, wherein the magnet is a permanent magnet.

6. The lancet device according to claim 5, wherein the triggering means comprise a coil, by which a magnetic field may be generated, which at least partially, preferably completely compensates for the retention force of the permanent magnet.

7. The lancet device according to claim 6, wherein the permanent magnet is situated fixed in relation to the coil.

8. The lancet device according to claim 6, wherein the coil is connected to an internal current source of the lancet device via a current buffer and/or a voltage converter to generate high-performance current pulses.

9. The lancet device according to claim 6, wherein a coil core is situated in the coil, which is formed by the permanent magnet or contains the permanent magnet.

10. The lancet device according to claim 9, wherein the permanent magnets enclose a drive chamber, in which a coil core is movable, whose movement is transmitted in operation to the lancet as the piercing and retraction movement.

11. The lancet device according to claim 10, wherein the permanent magnets are implemented as magnet rings.

12. The lancet device according to claim 1, wherein the magnetic field generated by the further permanent magnet of the drive means is reinforced by constructive superposition with a further magnetic field, which is generated using a coil current, in a first phase of a piercing movement, in which the lancet is accelerated by the drive force in the direction toward the skin surface.

13. A method for generating a piercing wound in a skin surface using a lancet, in which the lancet is accelerated along a piercing path in the direction toward the skin surface using a drive force generated by a drive spring, wherein the drive spring is held in a tensioned state before the triggering of a piercing movement using a magnetic retention force oriented opposite to the drive force, and the retention force is reduced enough to trigger a piercing movement so that the drive spring relaxes and the lancet is accelerated in the direction toward the skin surface under the effect of the drive force generated by the drive spring.

17. The method according to claim 13, wherein a further permanent magnet is used in the drive means which is situated with opposite polarity to the permanent magnet generating the retention force.

14. The method according to claim 14, wherein the magnetic retention force is generated using a permanent magnet and the retention force is at least partially, preferably completely compensated for by a magnetic field generated using a coil to trigger a piercing movement.

15. The method according to claim 15, wherein a magnetic field, which reinforces the retention force exerted by the permanent magnet, is generated using the coil to support a retraction movement of the lancet.

16. The method according to claim 15, wherein after a completed piercing, a mechanical oscillation of the drive spring is excited using the coil by periodic current surges, by which a pushrod carrying the lancet returns into its starting position, in which it is held by the retention force of the permanent magnet.