US3101084A

US3101084A - Syringe

Info

Publication number: US3101084A
Application number: US193093A
Authority: US
Inventors: Clark H Hamilton
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-05-08
Filing date: 1962-05-08
Publication date: 1963-08-20
Anticipated expiration: 1980-08-20
Also published as: GB984800A

Description

Allg- 201963 c. H. HAMILTON 3,101,084

sYRNGE Filed May s, 1962 `gaie.

r mm. mmmmmmY w /4 68 '7c/'2. 3: /6 44 42 22 40 4e 32 zFf. .5'.

ff) 24 f INV EN TOR.

f BWM United States Patent 3,101,084 SYRINGE Clark H. Hamilton, 737 Whitley, Whittier, Calif. Filed May 8, 1962, Ser. No. 193,093 '7 Claims. (Cl. 12S- 213) This invention relates generally to syringes andrelates more particularly to syringes having a very small volumetric lcapacity.

While the invention has particular utility embodied in syringes of extremely .small volumetric capacity, and is shown and described embodied therein, it is to be understood that its utility is not conlined thereto.

Various Aproblems and diiiiculties have been encountered in providing syringes of extremely small volumetric capacity land it is an object of the present invention to provide such a small capacity syringe whichvwill solve said problems and overcome said difficulties.

Itis another object of the invention to provide -a syringe of this character which has a zero loss of medicant or chemical sample.

It is still another object of the invention to provide a device of this character which will effectively handle extremely small `amounts of fluid (gas or liquid), such as medicants, chemicals, or the like. t

It is a further object of the invention to provide a device of this character wherein lthe needle lacts with both -as a syringe fluid reservoir and an injection element.

it is a still further object oi the invention to provide a device of this chanacter wherein a hard needle tubing is precisely titted with a plunger or plunger surface of a hard :metal dissimilar fromthe needle or interior surface rot the needle contacted by the plunger surface.

It is another object of the invention to provide a device of this character wherein the plunger displacement is read directly on a graduated scale.

It is still lanother object of the invention to provide va.

`device of this character whereinthere is a plunger guide assembly which supports the very small Adiameter plunger and 4permits free precise movements thereof.

lt is a further object of the invention to provide a seal effective for leakage of tluid, gas or liquid resulting from wear or corrosion.

lt is la still further object of the invention to provide a device of this character which prevents wiping in of dirt by the plunger from the outside, `such as would make the syringe inoperable. v Y

It is another object of the invention to provide a device of this character wherein capillary movement of liquid up the plunger and needle surfaces, such as woulddestroy `the precision of 'delivery volume, is prevented.

A further object of the invention is to provide ya device of this character wherein air seepage is prevented.

lt is a still further object of the invention toprovide a device of this character that is extremely accurate.

It is another object of the invention to provide a device of this character that is extremely reliable.

It is still another object of the invention to provide a device of this character that is relatively simple in construction.

A further object of the invention is to provide a device of this character that `may be readily and easily assembled, or disassembled, for servicing or replacement of parts.

It is a still further object of the invent-ion to provide ice a device of this character that is relatively inexpensive to manufacture.

The characteristics land advantages of the invention are -further sufliciently referred to in `connection with the following detailed 'description of the accompanying drawings, which represent one embodiment. After considering this example skilled persons will understand that many variations may be made without departing from the principles disclosed and I contemplate the employeinent of any structures, arrangements or modes of operation that are properly Within the scope of the appended claim-s.

Referring' to the drawings, which lare for illustrative purposes` only:

FIG. l is a longitudinal section through a syringe ernbodying the present invention;

FIG. 2 is a side view of the device;

FlG. 3 is an enlarged .longitudinal sectional View of a portion of said syringe;

f FIG. 4 is an enlarged side view, partially in section, or the outer end of the plunger assembly; i

FIG. 5 is a sectional view taken on line 5-5 of FIG.

,.fFIG. 6 is an enlarged longitudinal sectional view of an alternative arrangement.

Referring more particularly to the drawings, there is shown a syringe having a needle assembly, indicated generally lat 1t), including a hollow or tubular needle 12 provided -with a sharp point 14 at the outer or tree end thereof, said needle serving both las `a syringe reservoir and as` an injection device. Needle l2 may be of any suitable material, such as a hard metal, platinum alloy or stainless steelbeing examples of suitable materials for such needles. t

fAt the end of the needle opposite the point 14 said needle is provided with a female needle hub 16 having a wall 18 at its outer end provided with an axial opening therein for reception of the adjacent end portion of the needle 12, said needle being welded or staked, as indicated Yat 20, to said hub. Hub 16 has a recess extending inwardly from the opopsite end which is open. Extending from the open end, a portion of said hub is internally threaded las at 22, there being a gasket chamber 24 at the inner end `ol? the recess inthe hub 16.

The needle assembly -10 is connected to a volume indicating Ydevice or assembly, indicated `gener-ally at 26, saidassembly comprising a transparent body 28 of 'any suitable material, such as glass, for example. At the outer end the body 28 is provided with lan outwardly extending annular lian-ge 30 and there is `an faxia'l bore 32 through said body, said 'bore flaring outwardly tat the flanged end of the body, said flare portion of the bore being indicated at 34. t

Onthe exterior of the body there is a scale, indicated i `generally at 36, which is put on said body by any suitable-well known means, such as silver screening.

At the endof the body 28 opposite the iiange 30 thereof a zero stop and needle screw sleeve 40 is disposed `in the outer end portion of the bore 32., said zero stop and needle screw sleeve being cemented in said bore by any suitable well known cement, such as epoxy cement, for example. A portion of the outer end of sleeve it? extends outwardly beyond the adjacent end of the body 2S and has disposed thereon a Imale needle screw 42 having a reduced diameter externally threaded outer end portion 44 on which the yfemale threaded needle hub 16 is screwed. The male needle screw 42 is secured to the zero stop sleeve 4i) by any suitable means, such as, for example, welding, cementing or staking. It is to be noted that the inner end 46 of the zero stop sleeve 4t? is in exact register with the adjacentend of the scale 36 which is the zero point or mark of said scale. h

The interior diameter of the zero stop sleeve 40 1s sufliciently large to receive therein a forward end portion of a tubular inner plunger guide 50, said forward end portion of the guide Sill being secured in the Zero stop sleeve by any suitable means, such as cementing, or the like. Inner plunger guide is arranged axially in the bore 32 in body 2S and extends rearwardly from the stop sleeve 4l). As shown in FIG. l .-the inner plunger guide extends outwardly or rearwardly of the anged end of the body 28 although it need not extend this far rearwardly. It is to be noted that the forward end of the Zero stop sleeve and the forward end'of the inner plunger guide terminate in the same plane as the forward end of the reduced diameterexternally threaded part 44 of the male needle screw 42.

It is also to be noted that the zero stop'sleeve is relatively short and extends but a short distance into the forward end portion of the body 28, thus leaving a major portion of the bore 32 outwardly of `the outer end 46 of the'zero stop sleeve free ifor slid'able reception of a tubular volume indicating plunger Kguide 52, said Volume indieating plunger guide 52 being slidable on the inner plunger guide 50.

At its outer ends the volume indicating plunger guide has a button and plunger retaining groove 56 which is shown as bein-g integral with said volume indicating plunger guide 52 although saidbutton and plunger retaining screw may be a separate part secured to the plunger guide 52 by cementing, welding or other suitable means.

* The button and plunger retaining screw is provided with an axial bore of the same size as the bore or passage through the plunger guide 52 and forms a continuation thereof. A freeend portion of the button and plunger retaining screw is externally threaded for threadable reception of a thumb button 58 which has an axial tapped t bore `6i) inthe forward end thereof,the'rear end of said button being convex and said bore is closed at the convex orback side.

Inner plunger guide 50 has an internal bore or passage extending axially therethrough of substantially the same size as the internal diameter of the needle 12 and a plunger 6141is slidablyv disposed within the inner plunger guide and the bore or passage through the needle 12.

It is to be noted that the plunger is of a dissimilar material or metal from that of the needle and said plunger may be, for example, of tungsten or a chrome plated wire. Plunger 64 is precisely Y tted -within the boreor passage of the needle but is slidable therein.

TheV back or rear end of the plunger is secured to a plunger retaining button-66 by welding or other suitable means, said button being disposed in a recess 68 at the innerend of the tapped bore 60 of the thumb button and when said thumb button is screwed onto the button and plunger retaining screw of `the volume indicatinggplunger guide, the plunger and plungerguide 52 are secured together by the thumb button for operation together.

The plunger extends through the chamber 24 of the hub `16 and there is gasket material 70 in said chamber. The gasket material is of such character that it will flow under pressure which is created by the screwing of the hub 16 onto the part 44 of the needle screw 42. One suitable gasket material comprises fluorocarbon resins, such as Teflon (which is the registered trademark of E. I. du Pont de Nemours, Inc.) for such resins. The flowing under compression'of the gasket material provides a gas and liquid-tight seal for the plunger portion (i. passing through the seal 70- while permitting operative movements of said plunger.

The needle 12 not only functons as a needle but also functions as a volumetric syringe barrel reservoir, the volume of fluid in said needle being precisely displaced by l scoped position the inner or forward end of the volume indicating plunger guide engages the rear end of the zero stop sleeve at which time the forward end of the plunger bottoms at the needle point. Consequently there is no loss of fluid, gas or liquid handled by the syringe. In other words, there is a zero loss of such fluids.

The volume indicating plunger guide 52 and the inner plunger guide 50 support the plunger in alignment and allow yfree plunger movement with high precision. Further, by the precise fitting and telescoping plunger guides, or guide sleeves 5G and 52, respectively, the plunger displacement may be read on the graduated outboard scale 36. This plunger displacement is indicated by the 4forward end 74 of the volume indicating plunger guide as it registers with the various markings or lines of said scale 36.

The sealing gasket may be initially in the shapeA of a tubular part slidably receivable in the chamber 24 and slidably receiving the plunger. The gasket element must be" somewhat longer than the chamber 24 and when the hub 16 is screwed onto the part 44 of the needle screw l42, the material of said gasket is crushed or compressed in said chamber to sealingly engage the interior of the needle hub 16 and the portion of the plunger disposed therein at any particular time. f

The cmshedlsealing gasket acts in several ways. It seals for gross leakage of liquid or gas resulting fro-m wear or corrosion. It prevents wiping in of dirt by the plunger from` the outside which would make the syringe inoperative. Also, 4it prevents capillary movement of liquids up the plunger and needle surfaces Iwhich would destroy the precision of delivery volume `and air seepage is prevented by .the gasket assuring maximum accuracy.

In the above described arrangement the plunger issmall and requires -the support of the guide 5).

VThe alternative arrangement of FIG. 6 has a plunger of `greater diameter and rigidity than that first described. 'In this FIG. 6 arrangement the zerostop sleeve 40 is secured in the body 28 as. in the first described arrangement. The longitudinally extend-ing bore 40a of the stop sleeve 40 is adapted to op-erably receive the plunger 64, the inner end of the zero stop sleeve 40 having an inwardly tapered recess 40a which provides a guide for the free end of the plunger when `the device is being assembled. With `this .arrangement the free end of 'the plunger, when `said plunger is inserted into the bore 32 of the body 28' from the rear thereof, will enter the recess 46a and be guided into the bore 40a of said zero stop sleeve 4l). Upon further inward movement of the plunger vsaid plunger will pass through the bore of the sleeve 40, through the seal 70, `and into the bore of the needle 12, thus completing the assembly. Thereafter the hub 16 is tightened to compress the `seal about the plunger. In operation the forward end of `the volume indicating plunger guide 52 cooperates wi-th the scale 36 to indicate the plunger displacement and said forwardend bottoms on the inner end 46 of the zero stop-sleeve 40.

Inthis arrangement Ithe plunger and needle should also beof dissimilar metals, or .at leasttheir contacting surfaces should be of dissimilar metals. Very effective results have ybeen obtained with tungsten to stainless steel contacting surfaces for respective parts or a platinum ruthenium alloy to stainless steel for the respective contacting surfaces. v

The invention and its attendant advantages will be understood `from the foregoingdescription land it will be apparent that various changes may be made in the form, iconstruction and arrangement of the parts of the invention Without departing from the spirit and scope thereof or sacrificing its material advantages, the embodiment hereinbefore described being merely for purposes of illustration.

I claim: i f l. A syringe of very small volumetric capacity, comprising:

(A) a needle and volumetric barrel reservoir assembly icomprising (a) a needle of relatively hard met-al, said needle having a sharp point at its free end and having a bore therethrough, (b) and a female needle 4hub attached at one end to the end of the needle lopposite the point, said i hub having a bore extending inwardly from the free end, kan outer end portion of said bore being threaded, the inner or forward end of said bore comprising a gasket chamber; (B) a volume indicating device comprising,

(a) a transparent body having a bore therethrough, (aa) said body having a graduated scale there` on with a zero mark adjacent the forward end but spaced therefrom, p (bb) and an annular ange on the opposite end of said body, `(b) a tubular zero stop and needle screw sleeve secured within the forward end .portion of the bore through said 1body with the inner end in register` with the zero mark of the scale, the opposite end of said sleeve extending outwardly r of the `forwardend or said body, (c) a male needle screw secured to the forwardly Y extending portion of saidzero stop and needle screw sleeve, said needle screw having an externally threaded forward end portion for threadable reception in the needle hub, (d) an inner plunger guide having its forward end secured in said zero stop and needle screw sleeve and extending rearwardly in the bore of said 1 body, said inner plunger `guide having a bore therethrough and being of smaller external diameter than the internal diameter of the bore of the body; v t t (C) aplunger assembly including (a) `a plunger of vhard metal, di'lerent from the material of the needle, and having an external diameter precisely littin-g within the bore through the needle, i j

(b) a tubular volume indicating plunger guide slidably disposed on the inner plunger guide and slida'ble in the bore of the body,

(c) a plunger retaining button secured to the rear end of said plunger, `said plunger extending through the inner plunger guide land needle,

(d) :an externally threaded, tubular plunger retaining screw secured to the rear end of the volume indicating plunger guide,

(e) a thumb button having a tapped recess in the -forward end thereof threadably disposed on the plunger retaining screw, said plunger retaining button being `disposed in said recess `and held by the thumb button against the adjacent end of the plunger retaining screw to thereby secure together the parts of the plunger assembly,

(f) the parts of the plunger assembly being so proportioned and arranged that `when said assembly is moved forwardly in the volume indicating device and needle the forward end of the plunger bottoms at the needle point when the forward end of the volume indicating plunger guide abuts `against the rear end of the zero stop and needle screw sleeve, the thumb lbutton and plunger retaining screw being spaced rearwardly of `the flanged end of the body;

(D) and crushed sealing gasket means in the gasket of the threaded needle hub. 2. A syringe of very small volumetric capacity, comprising:

(A) a needle and Avolumetric barrel reservoir assembly comprising p (q.) a needle of relatively hard material, said needle having a bore therethrough and having a sharp point at its i'rree end,

(b) and a needle hubattached at one end to the end of the needle `opposite the point, said hub having a tapped bore extending inwardly from the free end;

(B) a volume indicating device comprising,

(an) a transparent Abody having a bore therethrough, p

j (mz) said body having a ,graduated scale thereon with a Zero mark adjacent the forward end but spaced therefrom, (bb) andan outwardly extending llange on j the `opposite end of said body,

(b) a tubular zeno `stop sleeve secured within the forward end portion of the ibore through said body with the inner end in register with the zero mark of the Scale, the opposite end of said sleeve extending `outwardly of the forward end of said body,

(c) an externally threaded needle screw secured to the Iforwardly extending portion of said zero stop sleeve, said needle screw being threadably received in the needle hub,

` (d) an inner plunger guide having its forward end secured in said zeno stop sleeve and extending rearwardly in the bore of said body, said inner plunger guide having a bore therethrough and `beingkof smaller external-diameter than the internal :diameter of the bore of the body; (C) a plunger assembly including,

(a) a plunger of hard material different from the material of the needle and precisely tting Within the bore through thevneedle,

(b) a `tubular 'volume indicating plunger lguide slidably `disposed :on the inner plunger guide and slidable in the bore tof the body,

(c) a plunger retaining button lon the rear end of said plunger, said plunger extending through the inner plunger lguide and the needle,

p (d) an externally threaded plunger retaining screw on the rear end yof the volume indicating plunger guide,

(e) and a thumb button having a tapped recess in the dorward end there-of threadabljy disposed on the plunger retainingscrew, said plunger retaining button being disposed in said recess and held by the thumbl button against the adjacent end of the plunger retaining screw, thereby securing together the plunger and volume indicating plunger guide,

(f) the parts of the plunger assembly being so proportioned and arranged Athat when said assembly is moved forwardly in the volume int dicating device and needle the forward end 'of the plunger bott-oms at the needle point when the Vforward end lof the volume, indicating plunger guide abuts against the rear end of the zero stop `sleeve, the thumb button and button and plunger retaining screw being spaced reart tappedl bore extending inwardly from the rear end; (B) a volume indicating device comprising,

(a) V a transparent body having a bore therethrough,

(aa) said body having a graduated scale thereon with-a Zero mark adjacent the forward end,

(bb) and an outwardly extending flange on thefopposite end of said (body,

(b) a tubular `zero stop Sleeve secured within the dorward end portion `of the bore through said body with the inner end inl register with the zero mark of the scale, the opposite end of said sleeve extending outwardly lof the forward end of said body,

(c) a tubular, externally threaded needle screw secured to fthe forwardly extending portion of said zero stop screw sleeve, threadably receiving the needle hub thereon,

(d) an inner plunger guide having its ilorward end secured in said zero stop sleeve and extending rearwardly in the bore of said body, said inner plunger `guide having a bore therethrough and being of smaller external diameter than the internal diameter of the bore of the body;

(C) a plunger assembly including,

() a plunger of hard material, different from the material of the needle, said plunger being precisely iitted within the needle, l

(b) a tubular rvolume indicating plunger guide slidably disposed Ion the inner plunger guide and slidable in the bore of the body,

(c) means for securing together the rear ends of said plunger and volume indicating plunger guide, said means including a thurnb button,

" (d) the parts of the plunger assembly being so proportioned and arranged that when the plunger is moved forwardly' in the volume indicating device and needle the lforward end of the plunger bottoms at fthe needle point when the forward end of the volume indicating plunger guide albuts against the rear end of the zeno stop sleeve.

4. In'a syringez (A) a needle and volumetric barrel reservoir assembly,

comprising: A Y

-Y (a)V la tt'ibulary needle having a sharp point at its free end, y

(b) and a tapped 'hub at the end lof the needle opposite the point,

(B) a vol-ume indicating device comprising,

(a) ya transparent tubular body having (au) a graduated scale Ithereon with a zero mark adjacent the doi-ward end,

(b) a zero stop sleeve secured -withinlthe forward end portion of the bore through lsaid body with the inner end in register with the zero mark of the sca-le, the opposite end of said sleeve exp tending' outwardly of the lforward end of said body,

(c) la tubular, externally threaded needle screw secured to the yforwardly extending portion of said zero stop yand needle screw sleeve,

(d) lan yinner plunger guide Iin said body with its forward -end secured in said Zero stop sleeve, said inner plunger lguide having a `bore theretbroughand being of smaller extern-al `diameter than the interior `oi" 'the body;

' (C) a plunger assembly including,

l(a) aplunger precisely fitting within the needle, (b) a tubular volume indicating plunger guide slidably disposed on the inner plunger guide,

(c). r`and lmeans operably securingf together the i volume indicating plunger guide and said plunger, (d) the` parts of the plunger assembly being so pnoportioned and arranged that when the plunger is moved forwardly in the volume indiv cat-ing device and needle the forward end of the plunger bottoms at -the needle point when the lforward end lof the volume indicating plunger `guide abnts `against the rear end of the zero stop sleeve. 5. In a measuring and discharge syringe of very small volumetric capacity:

(A) a needle and volumetric 'barrel reservoir assembly comprising:

(a) a tubular needle having a sharp point at its free end;

(B) la plunger precisely iitted `in said needle and slidable therein;

(C) guide and support means for said plunger and said needle;

(D) and Volume indicating means incorporated in the `syringe for indicating the volume displacement in said needle by said plunger.

6. `In a syringe:

(A) atubular needle;

(B) a plunger operably tted and needle;

(C) support means for said plunger;

(D) interconnecting means yconnecting said support means and needle and having a chamber therein for gasket and material, said plunger extending through said chamber;

(E) and crushable gasket material in said chamber and in engagement with the portion of said plunger in said chamber, said interconnecting means having parts movable relative to each other to compress said gasket material on said plunger to provide a seal for said plunger.

7. In a syringe:

(A) a needle and volumetric barrel reservoir assembly, comprising: Y

(a) :a tubular needle having a sharp point at its free end;

(B) a Volume indicating device comprising:

(a) a transparent body having a longitudinal bore therethrough, Y

(aa) a graduated scale thereon with a zero mark adjacent the yforward end,

(b) a zero stop sleeve secured within the forward end portion of the bore through said body with the inner end in register with the zero mark of the scale, the opposite end of said sleeve extending outwardly of the forward end of said body, said sleeve having an inwardly tapering recess in the inner end from which a longitudinal bore extends to the outer end, the ,endV of said needle opposite 'the -sharp pointed end being Secured to said stop sleeve;

(C) a plunger assembly including (a) a tubular volume indicating plunger guide slidably disposed in the bore of said body,

(b) a plunger preciselyrtting within the needle, and having a rearward portion disposed in said plunger guide,

(c) and means operably securing together the volume indicating plunger guide and said plunger,

(d) the parts of the plunger assembly being so .proportioned and Varranged that when the plungeris moved forwardly in the volume indicating `device and needle the forward end of the plunger bottoms at the needle point when the forward end of the volume indicating slidable in said 9 plunger guide labuts against the rear end of the 2,666,435 zero stop sleeve. 2,933,087

References Cite in the le of this patent UNITED STATES PATENTS 5 211g? 637,405 Papendell Nov. 21, 1899 157,455 827,693 Korb July 31, 1906 1,029,528 2,572,155 Hoy-t Oct. 23, 1951 561,5;98 2,590,895 Scarpellino Apr. 1, 1952 365,912

l@ Junkman et al Ian. 19, 1954 Hamilton Apr. 19, 1960 FOREIGN PATENTS Great Britain July 2, 1898 Sweden June 12, 1953 Germany May 8, 1958 `Canada Oct. 31, 1955 Germany Dec. 23, 1922

Claims

5. IN A MEASURING AND DISCHARGE SYRINGE OF VERY SMALL VOLUMETRIC CAPACITY: (A) A NEEDLE AND VOLUMETRIC BARREL RESERVOIR ASSEMBLY COMPRISING: (A) A TUBULAR NEEDLE HAVING A SHARP POINT AT ITS FREE END; (B) A PLUNGER PRECISELY FITTED IN SAID NEEDLE AND SLIDABLE THEREIN; (C) GUIDE AND SUPPORT MEANS FOR SAID PLUNGER AND SAID NEEDLE; (D) AND VOLUME INDICATING MEANS INCORPORATED IN THE SYRINGE FOR INDICATING THE VOLUME DISPLACEMENT IN SAID NEEDLE BY SAID PLUNGER.