US2015970A - Injection syringe - Google Patents

Description

@EL ily 393m J. scHoENE M5979 INJECTION SYRINGE Filed Deo. 25, 1935 Patented Oct. l, 1935 UNETED STATES anni PATENT QFFIC Application December 23, 1933, Serial No.

In Germany December 24, i932 Claims.

My invention relates to improvements in me-dical injection syringes, and refers more particularly to all-glass syringes. Such syringes, while having nuinerous advantages over al1-metal syringes, also have the disadvantage that the glass piston of the syring@ is apt to damage the bottom of the syringe cylinder by striking it too hard. Moreover syringes of the all-glass type share with all other injection syringes the inherent defect, that even after the syringe has been thoroughly sterilized by boiling, certain lasting forni of bacteria nulliiy the effect of this sterilization by developing during the periods in which the syringe is not in use.

The present invention is intended to obviate these deleterious defects and aims to produce a better syringe or" this type.

First and foremost, the dome or cone at the working extremity of the piston of the type of syringe made according to the present invention, is provided with a layer of absolutely pure silver, which in the first instance mitigates the shock occurring when the piston reaches the bottom oi the cylinder, while at the same time it frees the interior of the syringe of all bacteria or germs, and keeps the interior sterile by reason ci the oligodynarnic action of the silver.

Although for oligodynamic purposes, the silver layer might be situated at any part of the interior of the syringe, there are special advantages to be obtained by applying the silver to the deine or cone of the working face of the piston. is the silver is thus centrally situated, the eligcdynamic action, because the piston is movable within the cylinder, is to a certain extent also made movable, and is able to act at a great inany points. The fixation of the silver layer on the dome of the piston may be eiected in any suitable manner.

The dome of the piston may be made electrically conductive by means of a silver solution fused into the same in a known manner and the pure silver being electrolytically deposited thereon.

The appended drawing illustrates two embodiments of the syringe and its accessories or component parts.

Fig. l is a vertical longitudinal one of the embodiments.

Fig. 2 is a similar illustration modied syringe.

Figure 3 represents an illustration of a component part, viz. a shock absorbing device for the piston.

section through of a somewhat (Cl. 12S- 218) Figure l is a detail in perspective of the shock absorbing deviceof Fig. 3.

In Figures and 2 a so called al1-glass syringe is represented, where a indicates the glass syringe cylinder body, b the glass syringe piston, c the metallic threaded needle carrier fused into the glass syringe bottom, d denotes the hollow injection needle, and e in Figure 3 a preferably hexagonal nger support provided on the syringe cylinder. According to the present invention, a comparatively thick layer h (or h in Fig. 3) of silver is fixed or applied to the dome of the piston of the syringe in any known manner as by electricity. the elect of the piston striking the bottom of the syringe body, at the same time keeping or making the interior of the syringe sterile and germ free by means of its oligodynamic action. In Fig. l the layer h is secured to the piston by means of a screw i but this may be eliminated as seen in Fig. 2.

As is well known, the oligodynamic action of the pure silver is an action of the silveroxide produced by the action of the oxygen in the air or by other action and increased or reduced by means of an H2O2 ysolution or by means of manganese dioxide or other oxidization carriers.

An especially strong, long lasting, resisting and visible oligodynarnic action is attained, for example, if a somewhat concentrated, neutral, acid or alkaline solution of potassium hyper manganiurn is allowed to act on the silver dome of the piston of the syringe. This causes the formation of a chemical double compound of silver oxide and manganese dioxide (Ag2O 2MnO2). The silver oxide-manganese dioxide formed by alkaline potassium permanganate solution has been found to be especially suitable and advantageous. It possesses great resistance in respect to boiling and the action of dry heat as well as against the action of sulphur ions (sulphuretted hydrogen) and reducing substances, such as novocaine, or the like, which reduce or nullify the oligodynamic action of the pure silver, which has been activated and increased by the manganese dioxide.

The manganization of the silvered dome of the syringe piston b by means of AgzO-2Mn20 is effected in the most simple manner by immersing the dome of the piston for l to 2 hours in, for instance, a glass tube lled with a solution of potassium permanganate to a height of approximately 1 cm.

The protection oered to the syringe by reason of the shock absorbing eiiect of the pure silver This layer of silver mitigates dome of the piston may be further increased by means of a shock absorbing and braking device g for the piston b which is Vshovvn assembled in Figs. 2 and 3. This device g in the nature of a clip prevents on the one hand the accidental sliding or slipping of the syringe piston by exerting a lateral pressure on the periphery of the same and also eliminates th'e sharp impact of the piston on the bottom of the syringe, by engaging the abutment f of the same at the very moment of impact or a little beforehand. The abutment j on the syringe piston stem strikes upon the shock absorbing piston brake g and thereby slows down the movement of the piston.

I claim:

1. An injection syringe having a glass cylinder and a glass piston, and a buffer-like pad of soft metal formed on the Working end only of said piston as an extension thereof.

2. An injection syringe having a glass cylinder and a. glass piston, a buffer-like pad of soft metal formed on the Working end of said'piston as an extension thereof and contacting the cylinder Wall, and said metal having sterilizing properties.

3. An injection syringe having a glass cylinder and a glass piston, and a buffer-like pad of pure silver formed on the Working end of said piston as an extension thereof and engaging the cylinder Wall.

4. An injection syringe having a glass cylinder 10 and a glass piston, a layer of pure silver on the Working face of said piston, and a coating for said silver to augment the sterilizing action of the same.

5. An injection syringe having a glass cylinder 15 and a glass piston, a coating of pure silver on the Working face of said piston, and a coating of the double compound silver oxide manganese dioxide (Ag2O-2Mn02) on said silver.

JOSEF SCHOENE.

Images