US3216616A - Syringe with upper and lower bores - Google Patents

Description

1965 H. BLANKENSHIP, JR 3,216,616

SYRINGE WITH UPPER AND LOWER BORES Filed March 2. 1964 Q I i i gm V x7007 e," .5/0/7A'e/7Jfi 0, d/z

INVENTOR.

BY fig 5 2 ATTUR/VEVJ United States Patent 3,216,616 SYRINGE WITH UPPER AND LOWER BORES Homer Blankenship, Jr., 3601 White Oak Drive, Houston, Tex. Filed Mar. 2, 1964, Ser. No. 348,588 7 Claims. (Cl. 222-47) This invention relates to new and useful improvements in syringes.

An object of this invention is to provide a new and improved syringe from which accurately measured quantities of fluid may be dispensed by a plunger displacing same in a syringe tube having a calibrated 'bore, and wherein such bore is formed without grinding to dimension, thereby reducing the manufacturing cost and facilitating interchangeability of syringe tubes and plungers.

Another object of this invention is to provide a new and improved syringe having a body with at least two different internal bore dameters, and also having a plunger for each such bore.

A particular object of this invention is to provide a new and improved syringe wherein mixing and blending of two difierent fluids may be effected within the syringe body in measured quantities.

A further object of this invention is to provide a new and improved syringe having a syringe body with two different internal diameter bores, each of which is calibrated, and also having plunger means for drawing different measured quantities of fluids into such bores for mixing and/or blending in desired proportions and for thereafter discharging such mixed and/or blended fluids in measured quantity from the syringe.

Still another object of this invention is to provide a new and improved syringe having a body with a lower bore and an upper bore, wherein the upper bore is of a larger diameter than the lower bore, and wherein an outer plunger is slidable in the upper bore and an inner plunger is slid'able in the lower bore, such outer plunger sealing off the lower bore at its upper end to enable the inner plunger to discharge a measured quantity of fluid from the lower bore even though the inner plunger does not have a precision fit within the lower bore.

A specific object of this invention is to provide a new and improved syringe having a body made of glass or similar transparent material, with a two-part plunger therein, one part of which is made of plastic or other material capable of forming a seal in the bore of the body, and the second part of which is formed of metal wire or similar material for serving as a plunger.

The preferred embodiment of this invention will be described hereinafter, together with other features thereof, and additional objects will become evident from such description.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIG. 1 is an elevation of the syringe of this invention in the normal assembled condition; and

FIG. 2 is an exploded view, partly in elevation and partly in section, illustrating the principal components of the syringe of this invention in a disassembled condition.

In the drawings, the letter S designates generally the syringe -of this invention which includes atubular body 10 formed of glass or other similar material, preferably transparent.Such body 10 is provided with an upper bore 11 and alower bore 12. An outer plunger is disposed for movement in the upper bore 11 for drawing fluid into thebores 11 and 12 and for performing other functions, as will be Aninner plunger 20 is adapted to be positioned within the bore or longitudinal opening of theouter plunger 15, and its lower portion serves to discharge fluid in predetermined amounts from thelower bore 12 through aneedle 25, as will be more fully explained.

Considering the invention more in detail, thebody 10 is preferably precision bore glass tubing in which the glass is shrunk over a mandrel to obtain the prescribed inner dimensions. As will be more evident hereinafter, one of the advantages of the present invention resides in the fact that thebores 10 and 12 do not have to be precision ground, thereby eliminating an expensive grinding operation heretofore considered necessary in most types of syringes. By way of example, the inside diameter of thelower bore 12 may be 0.0206 inch plus or minus 0.0002 inch. Such tolerances are obtained with the precision bore tubing without the necessity for grinding. The upper bore 11 may have, by way of example, an inside diameter of 0.2500 inch plus or minus 0.0002 inch. Such dimensions can also be obtained with the precision bore tubing and without the necessity for grinding.

The upper bore 11 and theinner bore 12 are joined by an internal tapered orinclined wall surface 14 which serves as a seating or sealing surface in conjunction with theouter plunger 15, as will be described.

For convenience in handling, a flange 10a is preferably provided on the body at its upper end as illustrated. Theneedle 25 is secured to the lower end of thebody 10, preferably by inserting same within a suitable enlarged opening 12a at the lower end of the inner bore 12'. An epoxy resin or other adhesive suitable for bonding themetallic needle 25 to theglass body 10 is preferred for retaining theneedle 25 in an attached position with'respect to thebody 10. It is noted that theneedle 25 is shown with a reduceddiameter point 25a, but it will be understood that various other types of needles may be employed, depending upon the particular us Theneedle 25 is of course hollow throughout its length so as to admit fluid into thebores 12 and 11 and to also permit the discharge of fluid therefrom.

Theouter plunger 15 is preferablymade of polytetrafiuoroethylene, sold under the trademark Teflon, which material is especially suitable since it provides for substantially frictionless movement within the upper bore 11 while also maintaining effective seals as Will be more evident hereinafter. In the usual case, with the bore 11 of the internal diameter heretofore specified the external explained in detail.

diameter of theouter plunger 15 is 0.2497 inch.

Theouter plunger 15 has an internal longitudinal passage or opening 16, which is reduced in. diameter at itslower portion 16a.

Anannular ring indicator 17 is adhered or otherwise attached to the external surfaceof theouter plunger 15 near its lower end, but above its lowertapered surface 15a.Such ring indicator 17 may be made of black rubber or similar material so that it is visible when adjacent the graduations or volume indicia on the external surface of thebody 10 adjacent the upper bore 11 as best seen in FIG. 1.

The taper or inclination of thelower surface 15a corresponds closely to the taper or inclination of theseating surface 14 within thebody 10. Preferably, the angle of thetapered surface 15a extending upwardly and outwardly is slightly greater than the angle of inclination of thesurface 14 for more effective sealing contact when thesurfaces 15a and 14 are brought into engagement.

Aremovable nut 18 havinginternal threads 18a is provided at the upper end 15b of theplunger 15, which upper end 15b is also threaded externally for receiving theinternal threads 18a of thenut 18. Ordinarily thethreads 18a and 15b are tapered downwardly and outwardly so 'that as thenut 18 is threaded downwardly on the plunger example of 0.020 inch so that item freely move longitudinally within theinner bore 12.

Theupper portion 22 of theinner plunger 20 is made of brass or a similar material and it has an increased diameter or width as compared to thewire 21 to provide for increased strength-during longitudinal movements of theinner plunger 20. A handle orhead 23 is secured to theupperplunger portion 22 by welding, brazing or other suitable method so that thehandle 23 becomes an integral part of the inner plunger '20. It should also be noted that the lower wire -orplunger 21 is attached by brazing, bonding or other-suitable method to theupper plunger portion 22 so thatsuch portions 21 and 22 become integral for operating purposes. In some instances, it will be understood that the-entire inner plunger '20 may be made of a single metal or other material. As illustrated in the :;drawings, the upperl'brass rod section 22 has a diameter of inch so that it is of substantial thickness as compared :to thelower plunger 21. The inner passage or opening 16 of theouter plunger 15 has an opening sufficient for theupper portion 22 of theinner plunger 20. The reduced diameter opening 16a is of a size which is adequate for the passage of thelower plunger wire 21 therethrough. Preferably, the external surface of thewire 21 should have a diameter which is substantially the same as the internal diameter of the lower opening 160 for sealing purposes. The diameter of theopening 16 above the lower opening 16:: should be close enough to the diameter of .theplunger portion 22 so that when thenut 18 is :rotated and is moved downwardly with respect to theouter plunger 15, a compression or inward radial movement .of the material of theouter plunger 15 causes an-effective seal with theplunger portion 22 to prevent the escape of gas .or other fluids .between theplunger 15 and theplunger section 22, as will be further noted herein.

As illustrated in FIG. 1, thelower bore 12 is graduated or calibrated for microliters, while the upper bore 11 is graduated or calibrated for 1 milliliter. It will be understood that the volumes in each of thebores 11 and 12 may be varied by changing the dimensions thereof proportionately. For example, thelower bore 12 may be graduated for 1 microliter, 10 microliters, 20 microliters, 50 microliters or any similar relatively small quantities. The upper bore 11 may begraduated and calibrated for 1 milliliter, 2milliliters, or even more.

Because of the construction of the syringe of this invention, withthe two volume sections, it has great versatility and many uses.

.By way of example, thelower bore 12 may be utilized by itself in some instances for obtaining predetermined sample quantities of liquid. Thus, theneedle 25 is injected into the container .having the liquid to be sampled or tested, with the plunger at its lowermost position. The lower plunger wire 21may be in its lowermost position where it may be drawn upwardly so that its lower end is withdrawn into the opening 16a. Then, theouter plunger 15 and the innerplunger are moved upwardly together relative to thebody 10 to draw the liquid into the innerlower bore 12 until an adequate amount of liquid has been drawn in so as to fill thelower bore 12 and also a portion of the upper bore 11. Theouter plunger 15 together with theinner plunger 20 may be moved back and forth to purge theinner bore 12 and also the upper bore 11 of air or other gas when filling the tube orbody 10 with a liquid.

In any event, any air or gas which is present in the syringe .is discharged by forcing :the .plungers 15 and .20

downwardly so as to leave thelower bore 12 completely filled with the fluid. After theouter plunger 15 and theinner plunger 20 are forced downwardly together to cause thetapered surface 15a to engage thesurface 14, theinner plunger 20 is moved downwardly relative to theouter plunger 15 until the lower end 21a'of thelower plunger wire 21 is at the uppermost mark having theindicia 16 for 10 microliters in FIG. 1. If 10 microliters are to be discharged or dispensed, theinner plunger 20 is then forced downwardly so that thelower end 21a moves from theindicia 10 down to the indicia 0 within thelower bore 12. If a lesser amount of the fluid is to be measured out, such as seven microliters, the measured discharge may start at the time thelower wire 21a is at the indicia 7 for 7 microliters and then the discharge may continue until thelower end 21a reaches the 0 indicia mark. Any other predetermined quantities may of course be discharged with thelower wire 21 as will be understood.

In some instances, it is desirable to mix and/or blend two or more liquids in predeterminedquantities withinthe body 10 of the syringe S. For example, for dilution purposes, one fluid may be drawn into the syringe by pulling theouter plunger 15 and in theinner plunger 20 together upwardly from the lowermost position of theouter plunger 15 so as to draw the fluid into thelower bore 12. A suflicient amount of fluid may be drawn into thebores 11 and 12 to partially fill the upper bore 11, and then theouter plunger 15 together with theinner plunger 20 may be forced downwardly to force any gas or air out of thebores 11 and 12, leaving only the liquid. Theouter plunger 15 may then be seated with the lower taperedsurface 15a in contact with the taperedsurface 14, and the lower end of thewire 21a may be moved downwardly until it is aligned with the uppermost mark indicated by theindicia 10 in FIG. 1. The user then knows that he has a measured quantity of 10 mircoliters within thelower bore 12. Thereafter, theouter plunger 15, together with theinner plunger 20, are pulled upwardly to draw into the bores 11 and 12 a diluent or other liquid to be mixed with the first liquid already in thebore 12. The quantity of liquid which is drawn into thebores 11 and 12 is indicated bythe graduation marks on the external surface of thebore 10 in proximity to the upper bore 11, which as shown in FIG. 1 runs from 0 to IML (one milliliter). The two liquids are actually mixed together by the drawing of the second liquid into the syringe and the mixture is in a known proportion due to the known amounts of the liquids which have been drawn into thesyringe body 10. Therefore, such liquids are thereby mixed and blended and may be discharged as a mixed or diluted fluid. The indicia band 17 becomes aligned with the various graduation or calibration marks on the upper bore 11 in the preferred form of the invention.

In some instances, it is desirable to use the syringe S for gas samples. It is important in such cases to prevent any escape of gas through thelongitudinal opening 16. Normally, the sealing contact between the wall of theopening 16a and thewire 21 is suflicient to prevent liquid from passing therebetween, but gases may escapetherebetween in some cases. Therefore, thenut 18 is tightened or rotated so as to move downwardly on theouter plunger 15 to form a seal with theupper portion 22 of theinner plunger 20. Such seal is effective to prevent the passage of gases between the internal wall of thelongitudinal passage 16 and the external surface of thenod 22. It will be understood that the gases may be mixed and/ or blended in the same manner as heretofore described in connection with the liquids, although a purging of gas or air within the syringe prior to the introduction of the gas being tested or sampled is essential for accurate results. Therefore, a reciprocation of theplungers 15 and 20 within thebody 10 while theneedle 25 is within the gas to be sampled is important. For example, theneedle 25 may be injected into a balloon having the gas to be sampled and the gas may be drawn into the syringe S in a quantity greater than intended to be discharged for the sample. Then theneedle 25 may be withdrawn and theplungers 1S and 20 may be forced to their lowermost positions, evacuating all except a small amount of the gas which might remain at the lower end of thebore 12. This process can be repeated until it is absolutely certain that the only possible gas within the syringe is the gas to be sampled. Then the sample of the gas is obtained by again inserting theneedle 25 into the balloon or other source of the gas and the amount of the sample to be used is drawn into the syringe. All of the gas, except that which is to be dispensed in the measured quantity, is discharged from the bores of the syringe body 19. A second sample of another gas may be then drawn into the bores of the syringe S and mixed or blended in predetermined quantities to get a desired dilution or other blending.

It will be understood that the invention disclosed herein has great versatility and many uses, and the foregoing uses are merely illustrative. Since thewire 21 is a standard wire and thebore 12 is made by the precision shrinking process heretofore described, without the necessity for grinding, the syringe bodies and the plungers and may be standardized and interchangeable, which is not the case if precision grinding is required in thebore 12. Also, it will be understood that when thetapered surface 15a seats upon thesurface 14, a seal is obtained between the external surface of theplunger 15 and the internal surface of the bore 11 to prevent any fluid from flowing around theplunger 15. Thetapered surface 15a also tends to force the inner wall of theopening 16a into tight sealing engagement with thewire 21 to prevent any escape of fluid upwardly along therod 21 through theopening 16a. When the seal has been established, thewire 21 then moves down and as it moves downwardly from the lower end of theplunger 15, it displaces fluid in accordance with the cross-sectional area of thewire 21 and the stroke of such wire. Therefore, even though there is a space between thewire 21 and theinternal bore 12, a predetermined quantity of fluid is discharged by thewire 21 and such predetermined quantity is in accordance with the calibrations on the side of thebody 10 adjacent thebore 12 as illustrated in FIG. 1.

Also, when taking gas samples, it is desirable to provide a gas-tight seal around therod 22 by tightening thenut 18, as previously explained, so that the gas is prevented from escaping between theinner rod 22 and the wall of thepassage 16 in theouter plunger 15.

Various other modifications and changes will occur to those skilled in the art. It is understood that the particular materials disclosed herein are merely by way of example and ar not intended to be limiting.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. A syringe, comprising:

(a) a transparent tubular body having a lower bore and an upper bore,

(b) said body having volume marks for indicating variou volumes within each of said bores,

(c) said upper bore having a larger diameter than said lower bore,

((1) an outer plunger disposed in said upper bore for longitudinal movement therein,

(e) said outer plunger is visible through the wall of said upper bore,

(f) said outer plunger having a longitudinal opening therethrough,

(g) an inner plunger extending through said longitudi nal opening of said outer plunger and movable longitudinally thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore, and

(h) said inner plunger being visible through the wall of said lower bore.

2. A syringe, comprising:

(a) a glass body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

('0) a polytetrafluoroethylene outer plunger disposed in said upper bore for longitudinal movement therein,

(d) said outer plunger having a longitudinal opening therethrough, and

(e) a metal inner plunger extending through said longitudinal opening of said outer plunger and movable longitudinally relative thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore.

3. A syringe, comprising:

(a) a tubular body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinal movement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) said outer plunger having a sealing section,

(f) said tubular body having a seating surface between said upper bore and said lower bore adapted to be engaged by said sealing section for sealing off said lower bore from said upper bore,

(g) an inner plunger extending through said longitudL nal opening of said outer plunger and movable longitu-dinally relative thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore, and

(h) said inner plunger having a diameter enough smaller than the lower bore to avoid forming a seal therebetween, whereby the volume of fluid discharged by said inner plunger is a product of the cross-sectional area and the longitudinal stroke of said inner plunger.

4. A syringe, comprising:

(a1)J a tubular body having a lower bore and an upper ore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinal movement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) siaid outer plunger having a lower external tapered (f) said tubular body having an annular inclined surface between said upper bore and said lower bore adapted to be engaged by said tapered end of said outer plunger for forming a fluid-tight seal therewith, and

(g) an inner plunger extending through said longitudinal opening of said outer plunger and movable longitudinally relative thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore,

(h) said outer plunger sealing around said inner plunger to provide a fluid-tight seal therebetween.

5. A syringe, comprising:

(a?) a tubular body having a lower bore and an upper ore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinal movement therein,

(d) said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger comprising an upper pusher rod connected to a lower plunger wire, said wire extending through the lower end of said outer plunger and into said lower bore for discharging fluid from said lower bore, and

(f) said upper pusher rod providing increased strength as compared to said wire to prevent breakage or bending of the lower plunger wire in use.

6. A syringe, comprising:

(a) atubular body having :a lower bore and an upper bore,

(b) said upper bore having, a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinal movement therein,

((1) said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger extending through said longitudinal opening of said outer plunger and movable longitudinally relative thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore, and

(f) means for compressing the upper end of said outer plunger into sealing engagement with said inner plunger to prevent the escape of gas or other fluid through said longitudinal opening in said outer plunger.

7. AsyIing'e, comprising:

(a) a tubular body having a lower bore and an upper bore,

(b) said upper bore having a larger diameter than said lower bore,

(c) an outer plunger disposed in said upper bore for longitudinal movement therein,

((1) ,said outer plunger having a longitudinal opening therethrough,

(e) an inner plunger extending through said longitudinal opening of said outer plunger and movable longitudinally relative thereto and into said lower bore for discharging a predetermined quantity of fluid from said lower bore,

(f) the upper end of said outer plunger being formed of a compressible material and having external threads formed thereon, and

(g) a nut threaded on said external threads for slightly compressing the upper end of said outer plunger to form a fluid-tight seal with said inner plunger to prevent the escape of gas or other fluid through said longitudinal opening in said outer plunger.

References Cited by the Examiner UNITED STATES PATENTS 1,612,996 1/27 Waagbo 222-386 X 1,693,261 11/28 Sweetland.

2,841,145 7/58 Epps.

3,140,078 7/64 Krahe et al 222--386 X 3,153,496 10/64 Johnson 222--386 LOUIS J. DEMBO, Primary Examiner.

CHARLES R. CARTER, Examiner.

Claims (1)

1. A SYRINGE, COMPRISING: (A) A TRANSPARENT TUBULAR BODY HAVING A LOWER BORE AND AN UPPER BORE, (B) SAID BODY HAVING VOLUME MARKS FOR INDICATING VARIOUS VOLUMES WITHIN EACH OF SAID BORES, (C) SAID UPPER BORE HAVING A LARGER DIAMETER THAN SAID LOWER BORE, (D) AN OUTER PLUNGER DISPOSED IN SAID UPPER BORE FOR LONGITUDINAL MOVEMENT THEREIN, (E) SAID OUTER PLUNGER IS VISIBLE THROUGH THE WALL OF SAID UPPER BORE, (F) SAID OUTER PLUNGER HAVING A LONGITUDINAL OPENING THERETHROUGH, (G) AN INNER PLUNGER EXTENDING THROUGH SAID LONGITUDINAL OPENING OF SAID OUTER PLUNGER AND MOVABLE LONGITUDINALLY THERETO AND INTO SAID LOWER BORE FOR DISCHARGING A PREDETERMINED QUANTITY OF FLUID FROM SAID LOWER BORE, AND (H) SAID INNER PLUNGER BEING VISIBLE THROUGH THE WALL OF SAID LOWER BORE.

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