EJECTOR FOR AN AUTOMATIC LANCET ARM TECHNICAL FIELD
The present invention relates to an improvement of a medical instrument known as an automatic lancet. The automatic lancet has a spring loaded small needle used to prick the finger to obtain a blood sample. BACKGROUND OF THE INVENTION
U.S. Pat. No. 4,230,118 to Holman, et al. has be¬ come a generally accepted medical instrument used to prick the finger to obtain a blood sample. A housing contains a spring loaded pivoting arm which has a cylin¬ drical holder at its operating end. The holder holds a small needle which is housed in a plastic carrier. Push¬ ing a trigger releases the arm holding the needle. The needle pricks the finger from which the blood sample is taken. Presently the user must grab the exposed sharp needle and its surrounding carrier and pull the used needle out of the holder before inserting a new needle. This procedure poses the risk of having the medical tec ni- cian accidentally pricking his fingers on the used needle thus introducing the patient's blood directly into his own blood stream. This direct introductionof a patient's blood into the medical technician's blood poses serious health hazards to the medical technicians. SUMMARY OF THE INVENTION
It is, therefore, the primary object of the present invention to provide an improvement to the automatic lancet whereby the addition of a plunger inside the needle holder allows the medical technician to remove a used needle from
the holder by pushing the plunger, thus avoiding any con¬ tact with the used needle.
Other objects of this invention will appear from the following description and appended claims, reference being 5s had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views. BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a left side elevational view partially i0= cut away showing the working parts of the automatic lancet.
Figure 2 is a front elevational view of the automatic lancet showing the improved lancet holder having a plunger.
Figure 3 is a partial top plan view of the automatic lancet taken along line 3 - 3 of Figure 1 showing the 15 pivoting arm.
Figure 4 is a fragmentary sectional view of the pi¬ voting arm taken along line 4 -4 of Figure 3.
Figure 5 is a partial bottom plan view of the automa¬ tic lancet taken along line 5 - 5 of Figure 4 showing 2-0 the pivoting arm.
Figure 6 is a top perspective view of a lancet needle shown in dotted lines still encased in a protective tip.
Figure 7 is a left side elevational view of the automatic lancet cocked and ready to be actuated. ,5- Figure 8 is a left side fragmentary sectional view of the automatic lancet showing the lancet needle in its carrier snugly fit against the plunger.
Figure 9 is a left side elevational view of the auto¬ matic lancet with a fragmentary sectional view of the 0 lancet holder during ejection.
Before explaining the disclosed embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to the de¬ tails of the particular arrangement shown, since the inven- 5 tion is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring first to Figure 1, automatic lancet 1 is comprised of a housing having parts 2A and 2B. In opera¬ tion, detachable finger rest 3 is placed on top of the patient's finger (not shown). Pivot arm 7 is cocked back to the position shown in dotted lines. Trigger 5 is pressed to release pivot arm 7 fbrcsεully against stopper 8. Pivot arm 7 slides in groove 6. Spring 9 supplies the pivoting force to pivot arm 7 when couplings 10A and 10B are uncoupled by depression of trigger 5. The action end of pivot arm 7 is comprised of holder 4. The present inven¬ tion is comprised solely of plunger 11 inside holder 4, and the modification of holder 4 to include a hole on top for the plunger 11. Figure 2 shows the pivot arm 7 in a neutral position midway along groove 6. After cocking and upon actuation of trigger 5, the base 21 of pivot arm 7 slams into stopper 8. Arm 7 then retracts slightly to the neutral position. Holder 4 has a center groove 20 which expands to hold the needle (see Figures 7, 8 and 9). The top 25 of holder 4 is contoured inward providing an inside collar in holder 4 (see Figure 4) . Plunger 11 has a matching flange 22 which prevents plunger 11 from falling out of holder 4. Outer flange 23 on plunger 11 prevents plunger 11 from falling through holder 4.
Figure 3 shows how outer flange 23 on plunger 11 rests against the top 25 of holder 4.
Figure 4 shows how holder 4 lines up with hole 40 in finger rest 3. Figure 8 shows how the lancet needle fits in arm 7. Flange 22 abuts against holder top 25 and plunger 11 is thereby held slidingly engaged within holder 4. Flange 22 slidingly engages the cylindrical center 90 of holder 4.
Figure 5 shows the bottom of plunger 11 held inside holder 4.
Figure 6 shows needle 61 in dotted lines encased in protective tip 62. Protective tip 62 is twisted off before
use. Ribbed carrier 60 securely holds needle 61.
Figure 7 shows needle assembly 60, 61 and 62 mounted in operating position inside holder 4. Pivot arm 7 is in the cocked position whereby depressing trigger 5 would propel needle 61 through hole 40 into a patient's finger (not shown) .
Figure 8 shows how holder 4 has a hole 80 on top which guides plunger 11. Plunger flange 22 also guides plunger 11 down the cylindrical center 90 of holder 4 when plunger 11 is depressed in order to eject needle assembly 60, 61. Ribbed carrier 60 fits securely inside the cylin¬ drical center 90 of holder 4 during operation.
Figure 9 shows a medical technician's finger F depress¬ ing plunger 11 thereby ejecting needle assembly 60, 61 through hole 40 in finger rest 3. During ejection, pivot arm 7 would normally be in the neutral position after use as shown. The medical technician is protected from acci¬ dental pricking during insertion of a new needle assembly 60, 61, 62 because protective tip 62 is still in place (not shown) .