US2627856A

US2627856A - Syringe

Info

Publication number: US2627856A
Application number: US223053A
Authority: US
Inventors: Neil S Waterman
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-04-26
Filing date: 1951-04-26
Publication date: 1953-02-10
Anticipated expiration: 1970-02-10

Description

Feb. 10, 1953 N. s. WATERMAN SYRINGE Filed April 26, 1951 INVENTOR NEIL S. WATERMAN ill a t ATTORNEY Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE This invention relates to new and useful improvements in syringes.

An important object of this invention is toprovide syringes with superior aspiration. With normal syringes it is necessary that the needle be engaged into the body and the plunger pulled back a small distance before it is pushed completely forward in order to test whether or not a blood vessel has been pierced. If a blood vessel has been reached and the plunger is pulled slightly back the blood will ooze out and be readily seen. If this occurs the needle must be drawn completely out and a new spot located. Prior syringes, being collapsible tubes, make no provision for aspiration.

This invention proposes a new construction which makes it possible to immediately determine whether the needle has pierced a vein without requiring that the needle be drawn out a small distance, or other operation. Specifically, it is proposed that the syringe be constructed of transparent plastic or other transparent material and that an arrangement be provided which will permit the blood to flow through the needle and be readily visible through the plastic if a vein is pierced.

Another object of this invention resides in the provision of openings communicationg with the atmosphere and formed in the body of the syringe which will prevent the body from being air bound so that blood may readily flow through the needle and be visible if a vein is pierced. It is also proposed that the plunger of the syringe be so arranged that it may be forced downwards for ejecting the liquid of the syringe, and said plunger should close the said openings immediately upon the slightest downward motion of said plunger in order that the liquid may be entrapped and forced through the needle and into the body.

Another important advantage of the new syringe resides in the fact that because it is constructed. of transparent material the liquid contents may be inspected to determine whether or not it is still fresh enough to be used. Sediment or change of color of the liquid will easily be noted if the liquid has spoiled. In prior syringes inspection of the liquid was not possible because the tubes used to hold the liquid were not transparent.

Another important object of this invention resides in the provision of a resilient seal mounted across the bottom of the plunger of the syringe and arranged to hold the liquid in position adjacent the bottom of said plunger. A novel construction is'proposed-for mounting the resilient seal on the plunger and for using the edge portion of the resilient seal as a seal between the sides of the plunger and the cylindrical body of the syringe.

Another object of the invention is the construction of a syringe as described, which is simple and durable and which may be manufactured and sold at a reasonable cost.

For further comprehension of the invention, and of the objects andadvantages thereof, reference will be had to the following description and, accompanying drawing, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawing forming a material part'of this disclosure:

Fig.1 is a vertical sectional enlarged view of a syringe constructed in accordance with this invention.

Fig. 2 is a plan view of Fig. 1.

Fig. 3 is an elevational view of the plunger of the syringe shown in Fig. 1.

Fig. 4 is an enlarged sectional view of the resilient seal used in the syringe shown in Fig. 1.

Fig. 5 is an elevational view of the cylindrical body of the syringe.

Fig. 6 is a vertical sectional enlarged view of another syringe constructed in accordance with a modified form of this invention.

The syringe illustrated in Figs. 1-5 inclusive, includes a cylindrical body I0 having side walls II, an open top l2, 2. closed bottom I3, and a hollow steel needle I4 mounted through the closed bottom I3. A plunger I5 is slidably mounted in said cylindrical body I0 and is normally positioned in the top portion of the body It). A resilient seal I6 having an edge portion I! is. mounted around the bottom portion of said plunger I 5 and engages against the inner face. of the body In for forming a liquid seal between.

the plunger I5 and the body Ill.

The resilient seal I6 has a bottom portion I6 extending across the bottom of the plunger I5 for holding a quantity of liquid I9 against the bottom of said plunger IS. The top end 20 of the needle I4 projects upwards from the said closed bottom I3 of the body I0 and is normally spaced a short distance beneath the bottom I8 of the seal I6. The top end 26 of the needle is adapted to pierce the said bottom it when the plunger I5 is moved downwards in order that said liquid I9 may then be forced through the needle I4 and out of thebottom end of the needle I4. The plunger I5 has a peripheral roove I 9" near its bottom end.

aeszesc Beneath this groove I9 there is a flange 20. The resilient seal I6 is formed with a groove 2| spaced downwards a short distance from its top end. This groove 20 is adapted to receive and mate with the flange 20 to connect the seal 16 with the plunger 15. The seal l6 has a flared portion 22 above the groove 2| which will facilitate the engagement of the flange 20 of the plunger in the grooveZl. It is merely necessary to :force the flange downwards along the iiared portion 22 until it engages in the groove 2|. The plunger i5 is formed with an enlarged top portion 23 by which it may be easily held. Beneath this portion 23 there is threaded portion 24 used to hold a cap 25 for the syringe in position. A washer26 is interposed between the top edge 'of the cap '25 and the enlarged portion 23 of the plunger l5. The cap 25 enoases a portion of the plunger l5 and the entire cylindrical body Ill, including the needle M.

The side walls H of the cylindrical body iii are formed with openings 21 at their top edges. These openings 21' are in the nature of slots formed-downwards from the top edge of the body it. These slots 21 extend downwards a very small distance to a point beneath a shoulder 23 formed externally upon theresilient seal it while said plunger is in its normally raised position. The shoulder 28'isformed by reducing the diameter of the seal l6 -beneath said shoulder 23. The openings 21 will connect the outside atmosphere, when the cap 25 is removed, with the space 29 above the bottom of 'the body iii and beneath the seal I6. It'is proposed that the body it! and the plunger'lii be made'of stiff rigid type transparent plastic material, as styrene, which is transparent. The needle is may be made of steel. The resilient seal it should be made of flexible, resilient and rigid type plastic material such as polyethylene, which is translucent. The cap 25.may also be made of stiff rigid type plastic material. The bottom of the plunger is is formed with a recess 30 into which the top '29 of the needle 14 may engage when the plunger i5 is in its complete bottom position.

The operation of the device maybe understood from the following:

To use the syringe th 0111325 is first removed. Then the point of the needle [,4 is inserted into aportion of a persons body. The inner end or the needle 14 is observed to see whether blood starts entering the space ,29 to determine if a vein has been pierced. The blood -may easily enter the space 29'because the openings '2! in the body ill avoid air binding the spaeeifi. If a vein is pierced the needle id. is withdrawn and a new spot selected. If a vein has not been pierced the liquid i9 is injected by merely forcing the plunger is downwards. The top end 29 of the needle M will pierce the bottom is of the .resilient seal .56 when the plunger is started downwards. Then further downward motion of the plunger [5 will .iorce the'liquid 19 through the needle it. .Because the seal it is made from resilient material and because it is a tight fit between the plunger I5 and the inner face of the body ID, the seal [6 will prevent the liquid is from coming out between the body 9 and plunger I5, insuring that the liquid 13 will be forced through the needle M.

Before the liquid "I9 is injected it may easily be inspected to see whetheritis in good condition. If the color oftheliquid I9 has altered, or if the liquid l9 'hasbecome cloudy, or sedii ment has formed in it, the syringe is rejected and not used. The color of the liquid and the presence of sediment may be seen through the bottom of the plunger .l5.

In Fig. 6 another form of the invention has been disclosed. This syringe includes a cylindrical body 32 having side walls 33, an open top 34, a closed bottom 35, and a hollow needle 35 mounted through the closed bottom 35. The side walls 33 are formed with openings 31 at its top edge portion. A plunger 38 is slidably mounted in the cylindrical body 32 and is normally positioned in the top of the body 32. A resilient seal 39 is mounted across the bottom of the plunger 33. This seal 39 has an edge portion 60 mounted around the bottom portion of the plunger 38 and engaging the inner face of the body 32 for forming a liquid seal between the plunger 38 and body 32. The bottom portion of the seal 39 extends across the bottom of the plunger 38 and holds a quantity of liquid 4! against the bottom portion of the plunger 33. More particularly, the bottom portion of the plunger 38 is hollowed out forming a reservoir in which the liquid 4| engages. The cylindrical body 32 is formed with a large projection 42 which is of the same shape as the said hollowed out portion of 'the plunger 38 so as to be capable of mating with the said hollowed outportion when theplunger 3:; is forced downwards, and'in this way eject all or the liquid ll through the needle 3%. The hollowed out portion of the plunger 38 is formed with a top recessed portion '43 into which the top of the needle 35 may engage when the plunger 38 is in its extreme bottom position. The bottom portion of the seal 39 is adapted to be pierced on the top end of the needle 36 when the plunger 38 is moved downwards in order that the liquid 4| may be forced out from the bottom of the needle 35.

A cap 44 engages over the needle 38, over the body 32, and is threadedly engaged upon a threaded portion :35 formed near the top of the plunger 38. The plunger 33 has an enlarged top portion 35 by which it may be easily gripped. .A washer ll! is engaged beneath the top portion 46 and the top edge or" the cap 44. The openings 31 in the top portion of the body 32 normally extend slightly beneath the bottom portion of the seal 353 so that the space 58 between the bottom of the body 32 and the bottom of the plunger 38 is connected with atmosphere when the cap 44 is re moved. The bottom portion of the plunger 38 is formed with a peripheral groove intowhich the top portion iii of the resilient seal.39 engages and by which the resilientseal 39 is mounted upon the bottomof the plunger .38.

It is proposed that the plunger 33 and the body 32 be made from stiff transparent rigid type plastic material so that the space 48 and the liquid 1 may be inspected. The seal 39 is made from flexible and resilient rigid type plastic material such as polyethylene so that a good seal is formed between the plunger 38 and the cylindrical body 32 when the plunger 38 is moved downwards in the cylindrical body 32.

The operation and use of this form of the invention is identical to the prior form.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and the right is'reserved to all changes and modifications coming within the scope of the invention as defined in the appendedclaims.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. A syringe, comprising a cylindrical body having side walls, an open top, a closed bottom and a hollow needle mounted through said closed bottom. a plunger slidably mounted in said cylindrical body and norm-ally positioned in the top of said body, a resilient seal having an edge portion mounted around the bottom portion of said plunger and engaging against the inner face of said body for forming a liquid seal between said plunger and body, said seal having a bottom portion extending across the bottom of said plunger for holding a quantity of liquid against the bottom of said plunger, said bottom portion of said seal being adapted to be pierced on the top end of said needle when said plunger is moved downwards in order that said quantity of liquid may be forced out from the bottom of said needle when said plunger is moved downwards, said body and plunger being transparent, and said side walls of said body having in their top portions openings which extend below said plunger when said plunger is in its initial raised position.

2. A syringe as defined in claim 1, in which said plunger is formed with a peripheral groove around its bottom portion, and said edge portion of said seal engages said peripheral groove.

3. A syringe as defined in claim 1, in which said plunger is formed with a flange at its bottom and the edge portion of said seal is formed with a groove into which said flange engages for assisting in mounting said seal around the bottom portion of said plunger.

4. A syringe as defined in claim 3, inwhich the edge portion of said seal is flared above said groove to facilitate engaging said flange in said groove.

5. A syringe as defined in claim 1, in which said plunger is formed with a reservoir in its bottom for accommodating said quantity of liquid, and said cylindrical body is formed with a projection on its closed bottom shaped to mate into said reservoir when said plunger is moved down in said body.

6. A syringe as defined in claim 1, in which a cap encases said body, and said cap is removably mounted on said plunger.

NElL S. WATERMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 978,488 Roesch Dec. 13, 1910 1,456,469 Schwidetzky May 22, 1923 2,028,751 Barton Jan. 28, 1936 2,408,323 Lockhart Sept. 24, 1946 2,541,621 Thompson Feb. 13, 1951 FOREIGN PATENTS Number Country Date 573,611 Great Britain Nov. 28, 1945