Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS2595493 A
Publication typeGrant
Publication dateMay 6, 1952
Filing dateSep 9, 1949
Priority dateSep 9, 1949
Publication numberUS 2595493 A, US 2595493A, US-A-2595493, US2595493 A, US2595493A
InventorsLe Roy K Mills, Ollie F Slaby
Original AssigneeLe Roy K Mills, Ollie F Slaby
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Liquid extracting apparatus
US 2595493 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)


Patented May 6, 1952 UNITED STATES PATENT OFFICE LIQUID EXTRACTING APPARATUS Ollie F. Slaby, Parma, and Le Roy K. Mills, Lyndhurst, Ohio Application September 9, 1949, Serial No. 114,892

1 Claim. 1

Our present invention comprises novel appa ratus for extracting minutely measured quantities of fluid. and especially designed for extracting exactly measured minute quantities of blood for use in physiological researches such as the counting of corpuscles and the like.

For the purpose of blood counts it is necessary to puncture the patient and secure a very minute and precisely measured quantity of blood such as may be contained in a capillary tube; and it is further necessary to secure this relatively small exact amount of blood rapidly so as to avoid coagulation and without delay dilute such small quantity of blood with a suitable diluting fluid and this process must be accomplished very rapidly in order to obtain accurate results. In general the process involves the puncturing of the patient to obtain 'a drop of blood and the drawing of a quantity of the blood into a capillary tube exactly to a hair line graduation thereon to give a predetermined exact measure of a very minute quantity of blood and since the further procedure of the blood count is based on the assumption of an exact and very minute quantity of blood, it is apparent that the blood must not be drawn into the capillary tube even a hairs breadth off from the measuring graduation of the capillary tube.

The process of drawing the blood into the capillary tube and the subsequent dilution of the blood by drawing a diluting fluid into the capillary tube, also in an exact minute quantity, must necessarily be accomplished very rapidly in order to avoid coagulation of the blood. Hence, if the exact amounts of fluid are not drawn into the capillary tube initially, the entire operation must be repeated including the puncturing of the patient to secure a fresh drop of blood, and the instruments employed are required to be cleaned, sterilized, dried and made ready for the repetition of the operation which causes delay and annoyance both to the patient and to the practitioner.

l-Ieretofore it has been usual practice to draw the blood and diluting fluid into the capillary tube, for the purpose as above mentioned, by the use of a rubber hose attached to the capillary tube,'one end of the rubber hose being placed in the mouth of the practitioner and the blood and diluting fluid being drawn into the capillary tube by mouth sucking action. By such a process it is very difficult to procure an exactly measured amount of fluid of minute quantity as required and it takes a great deal of skill upon the part of the practitioner to procure a sum- 2 ciently close approximation of the exact quantity of fluid desired. For the practitioner who is required to perform this operation only occasionally, it is especially difficult.

It has been heretofore proposed to employ mechanical pumping devices of the piston and cylinder types with micrometer screw adjustment for the purposes of performing such operation, but such devices have not been successful despite their extremely high cost and precision manufacture because of the fact that with a piston and cylinder type pumping device a very small movement of the piston causes too great a movement of blood into the capillary tube and the piston and cylinder cannot be manufactured small enough proportionally to the size of the capillary tube to enable the minute movement of fluid in the capillary tube as required.

Moreover, in the manufacture of such piston and cylinder pump devices the parts thereof are required to be machined and lapped to very close tolerances at very great expense in order to provide satisfactory pumping action, and even though this type of pumping device is made with the greatest precision possible, it will not work without the necessity-for priming each time it is used. The necessity for priming of this type of pumping device renders it entirely impractical for use for the purposes hereof because of the time loss involved and the impracticability of having conveniently available priming means and priming fluid. However, the principal objection to piston and cylinder type pump device is that it cannot be made to draw the exact amounts of fluid required in the minute quantities necessary for the purposes described.

It is therefore a primary object of the present invention to provide apparatus for the purpose mentioned which will enable exactly measured minute quantities of fluid to be drawn into a capillary tube with highly and satisfactorily accurate control for the purpose mentioned and which apparatus may be readily manipulated with such control by relatively unskilled persons.

A further object of our invention is to provide apparatus for the purpose mentioned, having the desired characteristics of capability of accurate control, which apparatus may be manufactured at relatively small expense as compared with other less satisfactory devices and which apparatus does not require any machining operation to be performed thereon and does not require any priming in its use.

In carrying our invention into practice, We utilize a flexible, substantially air-tight fluid container, composed preferably of rubber or rubberlike material, and we dispose this flexible container within a rigid housing and connect a graduated capillary tube into fluid communication with said flexible container; and we further provide screw actuated plunger means engageable with the flexible container within its rigid housing for depressing or compressing the said flexible container to express fluid therefrom. We preferably utilize a flexible container having a bulbous or spheroidal shape and we specially form the surface of the plunger which contacts with the flexible container with a convex curvature for non-wrinkling engagement with the flexible fluid container.

For a detailed description of our invention, reference is made to the accompanying drawing in which:

Figure 1 is a view showing the complete appa ratus of our invention with the flexible fluid container, its housing, and the plunger head shown in section, and illustrating the flexible fluid container in non-compressed or fully expanded condition.

Figure 2 is a view similar to Figure l but showing the screw actuated plunger as when moved relative to the housing for action upon the flexibl fluid container to compress it to decrease the internal fluid capacity thereof.

In the drawings, the fluid extracting apparatus of our invention is designated as a whole by the letter A and comprises a substantially spheroidal housing, generally designatedby the numeral I, and consisting of two substantially hemispheroidal sections 2 and 3 which are fastened together by suitable fastenings such as the screws 4.

Within the housing I is disposed a flexible and resilient substantially air-tight fluid container which, as shown, is of bulbous or spheroidal shape and designated by the numeral 5. The flexible fluid container 5 preferably comprises a vacuum bulb composed of rubber or rubber like material such as soft rubber and the walls of which are of substantial thickness, as shown, so that the fluid container 5 is highly flexible and resilient and which normally retains its spheroidal shape, when undepressed, and after being depressed, when the depressing pressure is released, the fluid container 5 rapidly resumes its normal spheroidal shape.

The fluid container or vacuum bulb 5 is provided with a nipple 6 which extends through an opening in the lower section 3 of the housing to the outside thereof and provides a passage I for fluid communication between the interior of the container 5 and the exterior of the housing I. One end of the capillary pipette or graduated capillary tube 8 is received within the nipple 6 as shown. The capillary pipette 8 is of usual construction and comprises two capillary tubes 9 and I communicating with an intermediate mixing chamber II, the capillary tube 6 being provided with graduations 8a and the capillary tube In being provided with graduations Illa. The bulbous mixing chamber I I contains the usual mixing bead I2 which serves to prevent the blood corpuscles from aggregating when blood is drawn into the capillary pipette 8.

At the upper end of the section 2 of the housing I there is provided a threaded bushing I3 which receives and cooperates with the threads of a fine thread screw actuator I4 to the outer end of which is fixed a knurled head I for manipulation of the screw actuator I4 to rotate the same relatively to the threaded bushing I3 fixed to the section 2 of the housing. Swiveled to the inner end of the screw I4 within the housing I is an actuator head or plunger head provided with a convex bulb engaging surface I6a engageable with the vacuum bulb or flexible container 5 for depressing or compressing the same and the screw I4 is suitably actuated.

For the purpose of swivelly connecting the plunger head I6 to the screw I4, the head I6 is counter-bored axially of the screw I4 to receive a washer I'I within the larger diametered portion of the bore, which washer I1 is larger than the smaller diametered portion of the bore so as to act as a retainer for the screw I4, the inner end of which is undercut to receive the washer I1 and the end of the screw I4 is then peened over the washer to retain it on the screw. The larger diameter portion of the bore is then plugged up with a screw plug I8, the outer end of which is convex and made flush with the convex bulb engaging surface I'Ba of the plunger head l6.

In the use of the apparatus of our invention, the lower pointed end I9 is inserted in a drop of a patients blood while the vacuum bulb or flexible fluid container 5 is in depressed or compressed condition as shown in Figure 2 and then the knurled knob I5 is manipulated to rotate the screw I4 and move the actuator head I6 upwardly relative to the housing I to relieve the pressure on the vacuum bulb or fluid container 5 permitting atmospheric air pressure to force some of the blood into the capillary tube 9.

It will be seen that the preliminary actuation of the screw I4 to depress the vacuum bulb or fluid container 5 decreases the internal fluid capacity thereof driving air therefrom and when the screw I4 is actuated in opposite direction to withdraw the plunger I6 and relieve the pressure on the bulb 5, the internal fluid capacity thereof is expanded allowing more air to enter same thereby permitting the trapped air to expand into the bulb 5 and permit atmospheric air pressure to force blood up into the capillary tube 9.

It has been found that with the use of a screw I4 having a relatively fine thread of standard pitch, the movement of the plunger head in its engagement with the vacuum bulb 5 may be controlled with suflicient accuracy to allow only slight relief of bulb depressing pressure when the screw I4 is backed up such that the movement of fluid up the capillary tube 9 is relatively slow and can be stopped at the exact point desired in said capillary tube or passage 9.

Now, in the use of the apparatus for its intended purpose, the patients blood will be drawn up into the capillary tube 9 to the lower graduation 8a and it must be exactly stopped at that graduation mark as otherwise the blood count subsequently made will be inaccurate. When the blood is drawn up to the lower graduation mark 8a, the lower end I 9 of the capillary pipette is inserted into a diluting fluid and the screw I4 again actuated to relieve pressure on the bulb 5 to allow the fluid to rise in the pipette to the graduation mark Ifla and again the fluid must be stopped exactly at that graduation mark Ifla as otherwise the blood count subsequently made will be inaccurate.

The convex curvature of the bulb engaging surface I6a of the plunger head I6 is such as to cause smooth engagement of the plunger head with the vacuum bulb 5 in compressed condition, such as shown by Figure 2, whereby to prevent wrinkling of the flexible wall of the vacuum bulb 5 so 5 engaged. If the vacuum bulb 5 were wrinkled by engagement with the plunger head IE it would cause spurting or uneven flow of the fluid up the capillary tube which would result in inaccurate control of such flow.

From the foregoing it will be seen that our invention provides a very simple apparatus for the purpose which affords highly accurate control of the flow of fluid in minute quantities, which apparatus overcomes the disadvantages of devices previously proposed for this purpose, and our apparatus being capable of manufacture at relatively small cost compared with less satisfactory devices previously in use.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:

Fluid extracting apparatus of the class described, comprising, in combination, a flexible resilient fluid container of normally generally spheroidal shape and composed of rubber or like material, a rigid housing for said fluid container, said housing being of generally spheroidal shape corresponding to and confining said container therewithin, said fluid container having a nipple extending through said housing, a graduated capillary tube associated with said nipple for fluid communication between said capillary tube and the interior of said fluid container, and a screw actuated plunger comprising a screw actuator having threaded cooperation with said housing for axial movement relative thereto upon relative rotation of said actuator, and a plunger head swivelly connected to said actuator and disposed within said housing, said plunger head having a convex engaging surface for engagement with said fluid container to compress the same to decrease the fluid capacity thereof while closely confined within said housing, said fluid container being resilient to resume its normally spheroidal shape to increase the fluid capacity thereof upon movement of said plunger to relieve the compressing pressure on said fluid container.



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

UNITED STATES PAI E N I S Number Name Date 805,743 McConnell Nov. 28, 1905 1,447,790 Kovacs Mar. 6, 1923 1,963,886 Chilson June 19, 1934 2,153,105 Szecsi Apr. 4, 1939 2,166,842 Kagan Jul. 18, 1939 FOREIGN PATENTS Number Country Date 341,511 Great Britain Jan. 14, 1931

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US805743 *Jan 7, 1905Nov 28, 1905Central Scientific CoBarometer.
US1447790 *Apr 30, 1921Mar 6, 1923Theodor KovacsFilling device with rubber cap for fountain pens
US1963886 *Apr 4, 1931Jun 19, 1934Taylor Instrument CoDropper
US2153105 *Feb 27, 1936Apr 4, 1939Szecsi IstvanDevice for laboratorical measuring of liquids
US2166842 *Oct 19, 1937Jul 18, 1939Benjamin M KaganApparatus for determining the specific gravity of liquid media and the protein content of blood
GB341511A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2766907 *Mar 15, 1955Oct 16, 1956Robbins Instr CorpPressure infusion apparatus
US2769577 *Apr 21, 1950Nov 6, 1956Bernhardt StahmerBag content dispenser
US2771879 *Sep 9, 1954Nov 27, 1956Jr Alvin B SalisburyDisposable syringe
US2837093 *Jun 1, 1954Jun 3, 1958Joseph A RosenbergHypodermic syringe
US2873884 *Nov 5, 1956Feb 17, 1959Goldfarb Adolph ESquirting camera
US3017884 *May 1, 1958Jan 23, 1962Ballard Dale HApparatus for injecting or infusing fluids into patients and method of making same
US3061417 *Aug 31, 1960Oct 30, 1962United States Steel CorpConnection for side tube of reaction flask
US3263554 *Dec 26, 1961Aug 2, 1966Beckman Instruments IncCuvette with means for controlled volumetric displacement
US3327898 *Oct 19, 1964Jun 27, 1967Bioconsultants IncTitration means and method
US3343422 *Aug 12, 1965Sep 26, 1967Dwight G McsmithPipette safety device
US3640267 *Dec 15, 1969Feb 8, 1972Damon CorpClinical sample container
US3718133 *Jan 12, 1971Feb 27, 1973Damon CorpContainer unit for liquid samples
US3809068 *Feb 16, 1973May 7, 1974Damon CorpContainer unit for liquid sample
US4043042 *Oct 7, 1975Aug 23, 1977Johnson & JohnsonApplicator for tooth sealant
US4158035 *Mar 15, 1978Jun 12, 1979Byrd William JMultiple sample micropipette
US4236516 *Feb 16, 1978Dec 2, 1980Nilson Nils BSyringe and disposable container therefor
US4278089 *Nov 9, 1978Jul 14, 1981Howmedica, Inc.Wound drainage device
US4296071 *Nov 14, 1979Oct 20, 1981Boehringer MannheimPipette with elastic bellows
US4378333 *Dec 11, 1980Mar 29, 1983Laipply Thomas CDevice for preparing blood smears on glass slides and method therefor
US4511534 *May 26, 1982Apr 16, 1985John T. BennettLiquid transfer device
US4537231 *Aug 29, 1983Aug 27, 1985Becton, Dickinson And CompanyDispenser apparatus for simultaneously dispensing predetermined equal volumes of liquid including a disposable dispenser module
US4578060 *Jul 20, 1983Mar 25, 1986Howmedica, Inc.Wound drainage device
US4650662 *Nov 13, 1984Mar 17, 1987Cedars-Sinai Medical CenterPortable blood typing apparatus and method
US4653511 *Oct 5, 1984Mar 31, 1987Goch Thomas AMicrosample blood collecting device
US4738379 *May 13, 1986Apr 19, 1988Colpo Co., Ltd.Cartridge and its extractor
US4789526 *Dec 15, 1986Dec 6, 1988Pall CorporationVacuum diagnostic device
US4852620 *Apr 20, 1988Aug 1, 1989Eastman Kodak CompanyPipette with inverted bellows
US4976926 *Jul 28, 1988Dec 11, 1990Pall CorporationVacuum diagnostic device
US5035150 *Jan 8, 1990Jul 30, 1991Kontron Instruments Holdings, N.V.Pipetting method
US5098386 *May 17, 1991Mar 24, 1992Smith Ina LInfant nasal suction apparatus
US5118474 *Sep 19, 1988Jun 2, 1992Vitaly RogalskyLaboratory pipet
US5154702 *May 21, 1990Oct 13, 1992Wheaton IndustriesVariable dosage dropper system
US5186563 *Jan 7, 1991Feb 16, 1993Gebhard Patricia AFluid dispenser with applicator member
US5406856 *Mar 25, 1994Apr 18, 1995Eppendorf-Netheler HinzPipetting apparatus
US5773305 *May 2, 1996Jun 30, 1998Bayer Corp.Sample dilution module
US5807320 *May 2, 1996Sep 15, 1998Kammerer; K. ScottBottle squeezing method
US5836922 *Jun 21, 1996Nov 17, 1998Bernd HansenContainer for delivery of flowable material
US6135989 *May 13, 1998Oct 24, 2000Atad; JackPressurized intravenous infusion bag
US6261847Jul 10, 1998Jul 17, 2001Bayer CorporationSample dilution module with offset mixing chamber
US6629626 *Mar 7, 2000Oct 7, 2003Dyax, CorporationLiquid transfer device
US9221048 *Apr 5, 2012Dec 29, 2015Aptar France SasDropper dispenser
US20090007701 *Jul 3, 2007Jan 8, 2009Hadjis Peter TPivoting pipette device
US20090010809 *Jul 3, 2007Jan 8, 2009Hadjis Peter TManual pipette filler
US20120111130 *Mar 8, 2010May 10, 2012Juha TelimaaDilution tip
US20140020789 *Apr 5, 2012Jan 23, 2014Aptar France SasDropper dispenser
DE102005014572A1 *Mar 31, 2005Oct 12, 2006Eppendorf AgPipettiervorrichtung
DE102005014572B4 *Mar 31, 2005Jan 4, 2007Eppendorf AgPipettiervorrichtung
EP1707269A3 *Jan 13, 2006May 14, 2008Eppendorf AgPipetting device
WO1986003008A1 *Aug 22, 1985May 22, 1986Cedars-Sinai Medical CenterPortable blood typing apparatus and method
U.S. Classification73/864.11, 600/579, 600/584, 422/922, 222/214, 604/214, 141/24, 422/644, 422/645, 422/513, 422/624, 422/618, 422/507
International ClassificationB01L3/02
Cooperative ClassificationB01L3/0213, B01L3/021
European ClassificationB01L3/02C1, B01L3/02C