Disposable automatic lancet

• US 4,715,374 A
• Filed: 11/14/1986
• Issued: 12/29/1987
• Est. Priority Date: 11/14/1986
• Status: Expired due to Term

• Current Assignee: Medicore, Inc. (U.S. Renal Care, Inc.)
• Original Assignee: Medicore, Inc. (U.S. Renal Care, Inc.)
• Inventors: Maggio, Joseph
• Primary Examiner(s): Truluck, Dalton L.
• Assistant Examiner(s): Wilkens, F.
• Application Number:
  US06/930,515
• Time in Patent Office: 410 Days
• Field of Search: 128/314, 128/315, 128/329 R, 604/156, 604/157, 604/134-137, 604/110, 30/366, 30/367, 30/155
• 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 5/150908 by disconnecting components, e.g. breaking or rupturing of connected parts, e.g. piston and rod
• 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 5/15142 Devices intended for single use, i.e. disposable
• 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 disposable automatic lancet which can be used only once. A lancet blade is on a spring arm in a housing, and the spring arm is cocked just before the lancing procedure by pulling a flexible line extending through an opening in the housing. After cocking, the pull line may be broken off so that it cannot be pulled again, thus limiting the lancet to use only once.

Claims

1. In an automatic surgical lancet comprising:

a housing having a seat for receiving the tip of a patient'"'"'s finger and an opening in said seat for passing a lancet blade;

a spring arm inside said housing having a free end which is movable toward and away from said opening;

a holding element for holding said spring arm cocked in a stressed position in which its free end is held away from said opening;

a lancet blade holder on said free end of said spring arm;

and a lancet blade carried by said holder;

the improvement which comprises;

a pull line attached to said holder and extending outside said housing to be pulled to a position for cocking said spring arm in said stressed position, said pull line having a weakened region near its attachment to said holder which is readily broken by twisting the pull line, whereby to prevent another cocking of said spring arm after the pull line is broken;

said housing having an outer wall segment providing said seat which is inwardly displaceable by a push of the patient'"'"'s finger against said seat;

and means acting between said displaceable wall segment and said holding element to cause said holding element to release the spring arm from said cocked position for movement of its free end toward said opening when said displaceable wall segment is pushed inward.

2. In an automatic surgical lancet comprising:

a housing having a seat for receiving the tip of a patient'"'"'s finger and an opening in said seat for passing a lancet blade;

a spring arm inside said housing having a free end which is movable toward and away from said opening;

a lancet blade holder on the free end of said spring arm;

a lancet blade carried by said holder;

and a holding element for engagement with said holder to hold said spring arm cocked in a stressed position in which its free end is held away from said opening;

the improvement wherein;

said housing has an outer wall segment providing said seat which is displaceable inward by a push of the patient'"'"'s finger against said seat;

and further comprising;

means acting between said displaceable outer wall segment of the housing and said holding element to cause said holding element to release said holder and permit movement of the spring arm from said cocked position toward said opening when said displaceable wall segment is pushed inward;

and a pull line attached to said holder and extending outside said housing to be pulled to a position for cocking said spring arm in said stressed position, said pull line having a weakened region near its attachment to said holder which is readily broken by twisting the pull line, whereby to prevent another cocking of said spring arm after the pull line is broken.

3. In an automatic surgical lancet comprising:

a housing having a seat for receiving the tip of a patient'"'"'s finger and an opening in said seat for passing a lancet blade;

a spring arm inside said housing having a free end which is movable toward and away from said opening;

a lancet blade holder on the free end of said spring arm;

a lancet blade carried by said holder;

and a holding element for engagement with said holder to hold said spring arm cocked in a stressed position in which its free end is held away from said opening;

the improvement wherein;

said housing has an outer wall segment providing said seat which is displaceable inward by a push of the patient'"'"'s finger against said seat;

and further comprising;

means acting between said displaceable outer wall segment of the housing and said holding element to cause said holding element to release said holder and permit movement of the spring arm from said cocked position toward said opening when said displaceable wall segment is pushed inward;

said housing having a molded central frame piece of deformable and resilient plastic material which provides said spring arm, said displaceable outer wall segment of the housing, said holding element, and said means acting between said displaceable outer wall segment and said holding element;

said holding element being a flexible and resilient, elongated, cantilevered element extending toward said displaceable outer wall segment and presenting a free end which is engageable with said holder to hold said spring arm in its cocked position;

and said means acting between said displaceable outer wall segment and said holding element being a flexible and resilient, elongated arm having a cantilevered attachment to said displaceable outer wall segment and extending from its cantilevered attachment inward toward said free end of said holding element, said arm having a free end which is slidably engageable with said free end of said holding element to move said holding element out of engagement with the holder upon inward displacement of said displaceable outer wall segment;

and a pull line attached to said holder and extending outside said housing to be pulled to a position for cocking said spring arm in said stressed position, said pull line having a weakened region near its attachment to said holder which is readily broken by twisting the pull line, whereby to prevent another cocking of said spring arm after the pull line is broken.

4. An automatic surgical lancet comprising:

a housing having opposite side plates and a central frame engaged between said side plates, said central frame being a molded plastic body having;

a bottom segment;

a back segment extending up from said bottom segment at one end of the latter;

a rear top element having a cantilevered attachment to the upper end of said back segment and extending forward therefrom, said rear top element being flexible and resilient and terminating at its free front end in a depending lip which provides a rearwardly-facing shoulder, said lip presenting a downwardly and rearwardly inclined face on the front end of said rear top element;

a front segment extending up from said bottom segment at the opposite end of the latter, said front segment being joined to said bottom segment at a resilient corner of reduced cross-section to enable rearward pivoting of said front segment;

a finger-receiving segment attached to the upper end of said front segment and presenting a forwardly-facing concave seat with an opening therein for passing a lancet blade;

a front top element having a cantilevered attachment to said finger-receiving segment above said seat, said front top element extending rearward from its cantilevered attachment to said finger-receiving segment and terminating at its back end in a rearwardly and downwardly inclined face for sliding engagement with said inclined face on the front end of said rear top element;

a flexible and resilient spring arm extending up from said bottom segment behind said front segment and having a free upper end inside said housing;

a lancet blade holder on said free upper end of said spring arm, said holder having an upwardly-projecting extension with a forwardly-facing shoulder;

and a pull line extending from said holder down through said bottom segment, said pull line having a weakened region near its attachment to the holder;

and a lancet blade on the front end of said holder;

said pull line when pulled through said bottom segment retracting said holder to a position in which its upwardly-projecting extension engages behind said lip on the front end of said rear top element and said spring arm is cocked in a stressed position, said pull line being readily breakable in said weakened region by twisting the pull line after retracting said holder, whereby to prevent another cocking of said spring arm;

said front and finger-receiving segments being pivotable rearwardly about said corner between said front and bottom segments by the rearward force of a person'"'"'s finger against said finger-receiving segment, thereby displacing said front top element rearwardly to slide its inclined back end face across said inclined front end face of said rear top element and force said depending lip on said rear top element upwardly to release said upwardly-projecting extension on said holder, permitting the upper end of said spring to move forward and force said lancet blade through said opening in said seat on the finger-receiving segment to penetrate the finger engaging said seat.