US 2699784 A
Description (OCR text may contain errors)
G. M. K RAYL Jai; 1s, 195s SCARIFIER Filed Feb. 16. 1953 MIEHHHHHEHrECCNNH United States Patent O M SCARIFIER Gerhard Max Krayl, Tuttlingen, Wurttemberg, Germany Application February 16, 1953, Serial No. 337,130
1 Claim. (Cl. 12S-333) The present inven-tion relates to a scarifier. Instruments of this kind commonly consist of a shell or tube respectively provided with a plunger slidably arranged -the-rein. Said plunger has a sharp point at its front part and is controlled by a spring adapted to cause the sharp point to be driven out of the shell. A locking mechanism normally keeps the plunger in position against the action of the spring.
When, after the instrument has been brought into contact with a linger for instance, said locking mechanism is released the spring will shoot said plunger point out of the shell and makes it penetrate into the skin of the finger, thereby drawing blood, which is thereupon transferred by a pipette.
In practice, it has been noticed that infections are easily transmitted by said instrument. For this reason and in order not to be compelled to clean the whole mechanism after operation it has been proposed to construct the lancet bearing said sharp point not as an integral part of the plunger but as an interchangeable needle piece.
lt 1s the main object of the present invention to bring about a combination of the pricking needle and the other component parts of the instrument so as to enable quick -interchangeability of said needle.
Another object of the invention consists in arranging the pricking needle, although being interchangeable, in such a way that it is reliably kept in position and cannot get lost while in operation.
A further object of the invention consists in arranging the p-ricking needle in such a way that it need not be connected with the plunger but is in loose contact therewith.
According to the present invention the forward end of the shell is detachably provided with an extension furnished with a longitudinal bore adapted to serve as a sliding bearing for said needle, the latter being in loose contact with the forward end of the plunger.
A special feature of the invention consists in providing :the upper end of said pricking needle with a ilange, having a larger diameter than the needle itself, the said ange being adapted to slide within the shell and to prevent said pricking needle from sliding out of said extension by `being stopped by a shoulder at the upper end of said extension.
By way of example, a preferred embodiment of the invention is shown in the accompanying drawings which represent a longitudinal sectional view thereof.
2,699,784 Patented Jan. 18, 1955 ICC The scariiier consists of a shell 1 provided with a plunger 2 therein the middle part 3 of which has a larger diameter than the two end parts. Said middle part 3 serves as a base for a pressure spring 4, the upper end of ywhich abuts upon a shoulder 5 of shell 1. The threaded upper end 6 of plunger 2 is provided with a cap 7 which rests upon face 8 of shell 1.
At the side of shell 1 there is provided a pawl 9, hook 10 of which fits into an opening 11 ofI shell 1 in such a manner that when plunger 2 is drawn back by cap 7, thereby compressing spring 4, hook 10 is pressed under `a shoulder 12 of middle part 3 thereby securing plunger 2 in its raised position.
The lower end of shell 1 is provided with an inner thread 14 by means of which an extension 13, provided with a longitudinal bore 15, is screwed into said shell 1. The inner diameter of said bore 15 is such that it serves as a sliding bearing for a needle-point 16 of a lancet 17.
The upper end of lancet 17 is provided with a flange 18 being .in loose contact with the lower end of plunger 2, thus preventing the lancet 17 from sliding out of the longitudinal bore 15 by coming to rest after a certain Itravel upon the face of the threaded part of extension 13.
When placing the forego-ing described instrument upon a point 19 of the human body and putting locking mechanism 9, 10 into the opening position, plunger 2 under pressure of spring 4 shoots forward, thereby advancing ylancet17.
When the pricking needle 17 is to be cleaned, extension 13 is uns-crewed from shell 1 and needle 17 drawn forth to have same replaced by a new or cleaned one.
The invention is not limited to the example of embodiment shown and described and different modifications can be embodied without exceeding its scope. For inst-ance, the detachable connection between extension 13 and shell 1 may be provided by other means than by thread 14, e. g., by a screw-cap, a bayonet closure, pawls etc.
What I claim is:
Scarier comprising a shell, a plunger slidably arranged in longitudinal direction in said shell, a spring adapted to displace said plunger in longitudinal direction, a pointed needle adapted to emerge out of the shell when urged by the plunger, a releasable locking mechanism adapted to lock said plunger against the action of the spring, an extension threaded into the lower part of the shell, a longiltudinal bore within the extension and adapted to serve as a sliding hearing for the needle, the upper end of said needle being formed -as a flange having a larger diameter than said needle and said bores to limit outward movement of the needle in the extension, said needle being in loose cont-act with the plunger.
References Cited in the tile of this patent FOREIGN PATENTS 124,247 Sweden Mar. 15, 1949