US 3338239 A
Description (OCR text may contain errors)
United States Patent Filed Oct. 8, 1964, Ser. No. 402,539 3 Claims. (Cl. 128-329) This invention relates to a surgical puncturing device and more particularly to such a device for obtaining blood samples by making incisions of small depth into the skin.
It is an object of this invention to provide a simple, inexpensive puncturing device in which the puncturing needle is easily replaceable. A further object is to provide such a device in which a puncturing needle is detachably secured to a holder by magnetic attraction. A still further object is to provide such a device wherein only sterile needle surfaces will touch the subject from whom blood samples are being taken. Other objects will be apparent from the following description and claims.
In accordance with this invention, a puncturing needle having a head or flange of magnetic material is detachably secured to holder solely by one or more permanent magnets embedded in the holder. Preferably the head of the needle is large enough to cover the entire holder surface to which it is attached. A sterile puncturing needle can be placed on the holder, without being touched by the user, merely by bringing the portion of the holder in which the magnet is embedded into close proximity of the magnetic head on the needle. The holder includes a manually depressable plunger to eject the needle by moving it away from the magnet.
In the accompanying drawings:
FIG. 1 is a longitudinal sectional view of one embodiment of this invention showing the puncturing needle in position on the holder;
FIG. 2 is a plan view of the end face of the holder shown in FIG. 1;
FIG. 3 is a plan view of a modified needle suitable for use with the holder shown in FIG. 1; and
FIG. 4 is a longitudinal sectional view of a modified puncturing device showing the puncturing needle of FIG. 3 in position on the holder.
Referring to FIGS. 1 and 2, the holder of the puncturing device has an elongate tubular body member 2, preferably cylindrical, having a small diameter axial bore 4. The body member may be formed of any non-magnetic material, suitably plastic or stainless steel. Permanent magnets 6 are embedded in the sidewalls of the body member and have a surface 8 exposed that forms a portion of the end face 10 of the body member. The magnets may be oriented so that either one or both poles are exposed. A plunger 12, having an operating knob 14, is frictionally held in bore 4. Spring 16, arranged between the body member and knob, urges the plunger to a retracted position away from end face 10.
The needle consists of a disc-like head 20 formed of magnetic material and a centrally positioned depending pointed shaft 22. The shaft passes through the bottom of a plastic cup-shaped guide 24 which has a sidewall 26 extending beyond head 20. The head 20 is conformed to match the end face 10 of the body member and the body member is sized so that it will just fit inside cup 24.
When desiring to use the puncturing device, the user places the end of the body member in the plastic cup; the magnets attract the needle and securely hold it to the body member in the proper position as guided by the sidewalls of the cup. The user then grasps the body member to thrust the needle into the skin and withdraws it, the head of the needle serving as a stop to prevent too deep penetration. The needle is then ejected by de pressing the plunger to push it away from the magnets in end face 10.
The needles are readily sterilized, and can be conveniently supplied inserted point down in sterile foam or cotton. The skin is exposed only to the sterile surface of the needle and plastic cup, so danger of transfer of bacteria or virus from the holder is eliminated.
If desired, the magnetic needle head may be formed in a cup shape rather than using the separate guide 24.
FIG. 3 shows another needle suitable for use in this invention and is illustrated in operating position with the holder in FIG. 4. The pointed shaft 28 is press fitted into a central opening 30 of flange 32, which flange is made of magnetic material. The portion of the shaft 34 above the flange is sized to fit bore 4 of the holder to serve as a guide to maintain the needle in the proper position on the holder.
In the modified embodiment shown in FIG. 4, a stop means is provided for the plunger and the needle guide is integrally formed with the holder.
The body member 36 has a small diameter bore 38 and a chamber 40 of enlarged diameter. Plunger 42 has a flange 44 that is positioned in chamber 40. Spring 46 is arranged between the bottom wall of chamber 40 and flange 44 to urge the plunger to a retracted position, the top wall of chamber 40 serving as a stop to limit the travel of the plunger. In the manufacture of this device, the body member is conveniently formed from two semicylindrical halves; the plunger and spring are positioned in one half of the body member and the second half of the body is then placed in position and bonded to the first half. A peripheral ring 47, integrally formed with the body member, defines the end face 48 having embedded magnets 50, as previously described. The magnetic head 32 of the puncturing needle is sized to just fit inside ring 46, whereby the needle is guided to the proper position on the holder.
Although the end faces illustrated herein are concave to match a convex needle head, it is apparent that other matching shapes may be used if desired, for example, the end face and needle head may be flat.
According to the patent statutes, I have explained the principle and mode of practicing my invention and have described what I now consider to be its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
1. A surgical puncturing device comprising a cylindrical housing having an end face, an axial bore opening at said end face, a plunger within said axial bore extendable beyond said end face, resilient means to urge said plunger to a retracted position away from said end face, a permanent magnet embeddw in said housing and having at least one pole surface exposed at said end face, a removable needle having a shaft adapted to engage said bore and a disc of magnetic material matching said end face and secured to said shaft, said disc being normal to and spaced from the ends of said shaft.
2. A device according to claim 1 in which said housing has an integral peripheral ring extending outwardly from said end face and said disc lies within said ring.
3. A needle for a surgical puncturing device comprising:
(a) a shaft, having an upper cylindrical portion and a lower cylindrical portion, said upper portion having a larger diameter than said lower portion and said lower portion terminating in a surgical point, and
(b) a disc of magnetic material press fit on said lower portion and abutting said upper portion, said disc 3 4 being nonnal to and spaced from theends of said 2,627,423 2/ 1953 Copeman, shaft. 3,123,212 3/ 1964 Taylor et a1 206-634 R f en e Cited 3,208,452 9/ 1965 Stem 128-315 UNITED STATES PATENTS 3,221,739 12/ 1965 Rosenthal 128253 1 3 5 9 /1919 RICHARD A. GAUDET, Primary Examiner.
1,419,140 6/1922 Hutchinson- G. MCNEILL, Assistant Examiner.