Lancet Instrument

• US 20080103517A1
• Filed: 09/06/2005
• Published: 05/01/2008
• Est. Priority Date: 09/06/2004
• Status: Active Grant

• Current Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Original Assignee: Terumo Corporation
• Inventors: Yazaki, Hirofumi, Takemoto, Masafumi
• Granted Patent: US 8,038,694 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 5/15019 Depth adjustment mechanism using movable stops located inside the piercing device housing and limiting the travel of the drive mechanism mechanisms using distal end caps A61B5/150183, mechanisms at the piercing element carrier proximal end A61B5/150198
• CPC Class Codes: A61B 5/150259 Improved gripping, e.g. with high friction pattern or projections on the housing surface or an ergonometric shape
• 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 5/150832 by topography of the surface, e.g. Braille, embossed printing
• CPC Class Codes: A61B 5/150916 by blocking components, e.g. piston, driving device or fluid passageway
• CPC Class Codes: A61B 5/15113 Manually triggered, i.e. the triggering requires a deliberate action by the user such as pressing a drive button
• 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 5/1519 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

A lancet instrument detachably fitted to a lancing apparatus, comprising a lancet having a lancet body with a sharp lancet tip at its tip, a lancet hub fixed to the lancet body so that the lancet tip is exposed, and an elastic deformation part extended from the lancet hub in the tip direction and elastically deformable so that the distance thereof from the lancet body can be changed, a ring-like member fitted to the outer periphery of the elastic deformation part and releasable in the tip direction by changing the distance between the elastic deformation part and the lancet body, and a casing having a ring-like member contact part storing the lancet so as to be movable in the longitudinal direction and formed in the inner peripheral part thereof so that the ring-like member is brought into contact therewith and stopped to move in the tip direction and a tip opening through which the lancet tip can be projected. The lancet instrument thus obtained is so formed that the projection of the lancet tip through the tip opening of the casing is blocked by moving the ring-like member released from the elastic deformation part in the tip direction between the tip of the elastic deformation part and the ring-like member contact part to restrict the movement of the lancet.

Claims

1. A lancet instrument adapted to be detachably fitted to a lancing apparatus when used, comprising:

a lancet having a lancet body with a sharp lancet tip at its tip, a lancet hub fixed to said lancet body so that the lancet tip is exposed, and an elastic deformation part extended from said lancet hub and elastically deformable so that the distance of said elastic deformation part from said lancet body can be changed;

a ring-like member fitted to an outer periphery of said elastic deformation part and releasable from said elastic deformation part in a tip direction by changing the distance between said elastic deformation part and said lancet body; and

a casing storing said lancet so as to be movable in the longitudinal direction, the casing having a ring-like member contact part formed in an inner peripheral part of the casing so that the ring-like member is brought into contact with the ring-like member contact part and is blocked to move in the tip direction, and the casing possessing a tip opening through which said lancet tip can be projected;

wherein the projection of said lancet tip through said tip opening of said casing is blocked by moving said ring-like member released from said elastic deformation part in the tip direction between the tip of said elastic deformation part and said ring-like member contact part to restrict the movement of said lancet.

2. The lancet instrument according to claim 1, wherein

an inner periphery of said ring-like member has a tapered shape such that an inside diameter of the ring-like member gradually increases in the tip direction;

and

an outer periphery of a fitting part of said elastic deformation part, to which said ring-like member is fitted, has a tapered shape such that an outside diameter of the fitting part gradually increases in the tip direction.

3. The lancet instrument according to claim 2, wherein the tapered shape of the inner periphery of said ring-like member possesses a taper angle in the range of 1 to 45 degrees.

4. The lancet instrument according to claim 1, wherein said ring-like member is irreversibly released from said elastic deformation part.

5. The lancet instrument according to claim 1, wherein said elastic deformation part is comprised of a plurality of projected parts spaced from each other.

6. The lancet instrument according to claim 1, wherein

said casing is provided at an inner peripheral part thereof with a lock part inhibiting the movement of said ring-like member in a base end direction;

and

said ring-like member fitted to said elastic deformation part is brought into contact with said lock part and released from said elastic deformation part by moving said lancet in the base end direction relative to said casing.

7. The lancet instrument according to claim 1, wherein

said casing is provided at an inner peripheral part thereof with a hub engaging part for engagement with an outer peripheral part of said lancet hub;

and

a force for releasing said lancet hub from said hub engaging part is greater than the force for releasing said ring-like member from said elastic deformation part.

8. A lancet instrument detachably fittable to a lancing apparatus, comprising:

a casing possessing a hollow interior portion communicating with an open tip end at a tip end of the casing which opens to outside the casing, the casing possessing an inner peripheral surface;

a lancet movably positioned in the hollow interior portion of the casing, the lancet comprising a lancet hub and a lancet body possessing a sharp lancet tip, the lancet body being secured to the lancet hub so that the lancet hub and the lancet body move together, the lancet body possessing a sharp lancet tip;

a ring-shaped member fitted to an outer periphery of a tip end portion of the lancet hub;

an inwardly directed lock part provided on the inner peripheral surface of the casing;

the lancet being movable relative to the casing from a first position in which the sharp lancet tip of the lancet body is positioned on a base end side of the open tip end of the casing so that the sharp lancet tip does not project beyond the tip end of the casing to a second position in which the sharp lancet tip of the lancet extends through the open tip end of the casing and the ring-shaped member fitted to the outer periphery of the tip end portion of the lancet hub is positioned on a tip end side of the lock part of the casing; and

the lancet being movable relative to the casing from the second position toward a third position during which the sharp lancet tip of the lancet body is retracted into the interior of the casing so that the sharp lancet tip does not project beyond the tip end of the casing and the ring-shaped member contacts the lock part of the casing to move the ring-shaped member relative to the lancet hub toward a tip end of the lancet hub.

9. The lancet instrument according to claim 8, wherein the tip end portion of the lancet hub comprises a plurality of circumferentially spaced apart projecting parts on which the ring-shaped member is fitted.

10. The lancet instrument according to claim 9, wherein the ring-shaped member is irreversibly moved off of the projecting parts of the lancet as a result of the ring-shaped member contacting the lock member while the lancet is moved from the second position towards the third position.

11. The lancet instrument according to claim 8, wherein the ring-shaped member comprises first and second ends, the first end of the ring-shaped member being closer to the tip end of the casing than the second end of the ring-shaped member, the ring-shaped member possessing an inner diameter that gradually increases towards the first end of the ring-shaped member.

12. The lancet instrument according to claim 8, wherein the inner peripheral surface of the casing possesses an inwardly extending contact part, the contact part being spaced from the lock part in a direction toward the tip end of the casing, the contact part having an inner dimension smaller than an outer dimension of the ring-shaped member.

13. The lancet instrument according to claim 12, wherein the contact part and the lock part are spaced apart by a distance greater than an axial extent of the ring-shaped member.

14. The lancet instrument according to claim 8, wherein the ring-shaped member is irreversibly moved off of the tip end portion of the lancet as a result of the ring-shaped member contacting the lock member while the lancet is moved from the second position towards the third position.

15. The lancet instrument according to claim 14, wherein the inner peripheral surface of the casing comprises an inwardly extending hub engaging part that engages an outer periphery of the lancet hub when the lancet is in the first position, and wherein a force required to release engagement of the lancet hub from the hub engaging part is greater than the force required to move the ring-shaped member off of the outer periphery of the tip end portion of the lancet hub.

16. A lancet instrument detachably fittable to a lancing apparatus, comprising:

a casing possessing a hollow interior portion communicating with an open tip end at a tip end of the casing which opens to outside the casing, the casing possessing an inner peripheral surface;

a lancet movably positioned in the hollow interior portion of the casing, the lancet comprising a lancet hub and a lancet body possessing a sharp lancet tip, the lancet body being secured to the lancet hub so that the lancet hub and the lancet body move together, the lancet body possessing a sharp lancet tip;

a ring-shaped member fitted to an outer periphery of a tip end portion of the lancet hub;

an inwardly directed contact part provided on the inner peripheral surface of the casing, the contact part forming an inner dimension smaller than an outer dimension of the ring-shaped part;

the lancet being movable relative to the casing from a first position in which the sharp lancet tip of the lancet body is positioned on a base end side of the open tip end of the casing so that the sharp lancet tip does not project beyond the tip end of the casing to a second position in which the sharp lancet tip of the lancet extends through the open tip end of the casing;

the lancet being movable relative to the casing from the second position toward a third position during which the sharp lancet tip is retracted into the interior of the casing, the ring-shaped member engages a lock part of the casing to cause the ring-shaped member to move relative to the lancet in a tip end direction, and the ring-shaped member is positioned on a base end side of the contact part; and

the ring-shaped member contacting the contact part of the casing when the lancet, which has been moved from the second position towards the third position, is moved in the tip end direction to stop movement of the lancet and prevent the sharp lancet tip from projecting beyond the tip end of the casing.

17. The lancet instrument according to claim 16, further comprising an inwardly directed lock part is provided on the inner peripheral surface of the casing, the lock part and the contact part being spaced apart from one another along a longitudinal extent of the casing, the lock part possessing an inner dimension smaller than an outer dimension of the ring-shaped member so that as the lancet is moved from the second position towards the third position, the ring-shaped member contacts the lock part and causes the ring-shaped member to be irreversibly moved off of the tip end portion of the lancet hub.

18. The lancet instrument according to claim 17, wherein the contact part and the lock part are spaced apart by a distance greater than an axial extent of the ring-shaped member.

19. The lancet instrument according to claim 16, wherein the tip end portion of the lancet hub comprises a plurality of circumferentially spaced apart projecting parts on which the ring-shaped member is fitted.

20. The lancet instrument according to claim 16, wherein the inner peripheral surface of the casing comprises an inwardly extending hub engaging part that engages an outer periphery of the lancet hub when the lancet is in the first position, and wherein a force required to release engagement of the lancet hub from the hub engaging part is greater than the force required to move the ring-shaped member off of the outer periphery of the tip end portion of the lancet hub.