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Publication numberUS2423173 A
Publication typeGrant
Publication dateJul 1, 1947
Filing dateMar 30, 1945
Priority dateMar 30, 1945
Publication numberUS 2423173 A, US 2423173A, US-A-2423173, US2423173 A, US2423173A
InventorsEdward L Brady, Lawrence E Glendenin
Original AssigneeEdward L Brady, Lawrence E Glendenin
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safety pipette
US 2423173 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

July 1947- E. L. BRADY ET AL 2,423,173

. SAFETY PIPETTE Filed March 30, 1945 INVENTOIK Patented 1, 1947 SAFETY PIPE'I'IE Edward L. Brady and Lawrence E. Glendenin,

Oak Ridge, Tenn,

assigllors to United States of America, as represented by the Director of the Oflice of Scientific Research and Development, Ofice for Emergency Management Application March 30, 1945, Serial No. 585,7ii6

This invention relates to pipettes and particularly to structural features of pipettes adapted to user to draw liquid into his mouth which result is very undesirable, especially when the liquid is corrosive or radioactive.

An object of the invention is to provide a pipette construction which will prevent inadvertent flooding of the mouth of the user.

Other objects and advantages of the invention will be evident from the following description when read in connection with the accompanying drawing the single figure of which shows in perspective a pipette incorporating the invention. The pipette as shown consists of a suitable intake tube in which may have a calibration mark I I, a mouthpiece l 2 and an intermediate enlarged portion l3 having a part of the wall tom away to show a wall member ii. In accordance with the invention the wall it is pervious to air, but when wet is not pervious, at least under pressure differences which can be provided by oral suction by laboratory workers. ably consists of a sintered glass disc sealed in the portion It. and the medium grade disc manufac- The wall I prefertured by Corning has been found to ,be quite'satisfactory. Inasmuch as the primary function of the wall is to prevent sudden rushes of-liquid to the mouthpiece i2 and need not provide anabsolute barrier to the passage of a liquid, it will the barrier member is a thin 2 Claims; (Cl. 222-189) 2 be evident that the porosity of the wall It may vary considerably and still perform its protective function.

It will be understood that the invention is not limited in its application to the particular pipette illustrated.

We claim:

1. A pipette adapted to pick up liquid by oral suction comprising a tubular member open at both ends and having an'enlarged portion intermediate said ends, and a barrier member within said enlarged portion and having its periphery secured to the wall of said tubular member, said barrier member being pervious to air when .dry and impervious to air and liquid when wet.

2. A pipette as claimed in claim 1 in which disc of sintered EDWARD L. BRADY. LAWRENCE E. GLENDENDJ'.

REFERENCES CITED The following references are of record in the glass.

file of this patent: I

25 UNITED STATES PATENTS Number Name Date 2,376,231 Cohn May 15, 1945 2,114,748 Prausnitz Apr, 19, 1938 Luertzing Nov. 8,1938

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2114748 *May 2, 1935Apr 19, 1938Firm Jenaer Glaswerk Schott &Method of making porous filter bodies of particles of glass
US2136170 *Dec 15, 1936Nov 8, 1938Ace Glass IncGlass filter
US2376231 *Feb 12, 1942May 15, 1945David J CohnPipette
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2634028 *Dec 31, 1947Apr 7, 1953Bell Telephone Labor IncMercury dispenser
US2635784 *May 11, 1950Apr 21, 1953Bering Horace LVent plug closure
US2685800 *Nov 12, 1952Aug 10, 1954Kopp Scient IncPipet for microanalysis
US2720109 *Jan 13, 1951Oct 11, 1955American Cyanamid CoPowder density determination
US3033420 *Nov 2, 1959May 8, 1962Gwinn Mabel CMethod and apparatus for dispensing liquids
US3124828 *Dec 5, 1961Mar 17, 1964 Liquid impermeable vent
US3125255 *May 29, 1961Mar 17, 1964 Kaiser
US3134512 *Jul 25, 1961May 26, 1964Beckman Instruments IncDispensing apparatus
US3215500 *Jun 12, 1961Nov 2, 1965Donald L BittnerLaboratory mixer-separator
US3315844 *Jan 13, 1965Apr 25, 1967Air Prod & ChemDispensing apparatus
US3864979 *Mar 30, 1973Feb 11, 1975Becton Dickinson CoBlood sedimentation tube barrier
US3865549 *Oct 2, 1972Feb 11, 1975Wellcome FoundAuto-analytical apparatus and analytical methods
US3891392 *Jan 24, 1973Jun 24, 1975Peter Alan BettsMethod of maintaining a column of liquid within an open-ended tube, and a tube device for carrying out the method
US3912129 *Sep 30, 1974Oct 14, 1975Hughes Aircraft CoLiquid dispenser
US4210156 *Apr 24, 1978Jul 1, 1980Bennett Elmer TFinger stick blood collection apparatus
US4267729 *May 14, 1979May 19, 1981Eddelman Roy TVolumetric pipettor
US4350049 *Nov 5, 1980Sep 21, 1982Boehringer Ingelheim GmbhDevice and process for drawing off very small quantities of powder
US4378333 *Dec 11, 1980Mar 29, 1983Laipply Thomas CDevice for preparing blood smears on glass slides and method therefor
US5058441 *Dec 18, 1989Oct 22, 1991The United States Of America As Represented By The Department Of Health And Human ServicesSafety pipette and adaptor tip
US5059398 *Jul 22, 1985Oct 22, 1991Drummond Scientific CompanyDisposable preselected-volume capillary pipet device
US5114679 *Aug 27, 1990May 19, 1992Eastman Kodak CompanyMethod of using a pipette
US5209128 *Dec 18, 1990May 11, 1993The United States Of America As Represented By The Department Of Health And Human ServicesSafety pipette and adaptor tip
US5217693 *May 29, 1990Jun 8, 1993Mark AndersonEmbryo washing apparatus and process
US5437979 *Aug 24, 1992Aug 1, 1995Beckman Instruments, Inc.Solid phase system for sequential reactions
US5580529 *Jun 12, 1995Dec 3, 1996Bio-Plas, Inc.Aerosol and liquid transfer resistant pipette tip apparatus
US6343717 *Nov 21, 2000Feb 5, 2002Jack Yongfeng ZhangPre-filled disposable pipettes
US6803021 *Mar 31, 1999Oct 12, 2004November Ag Novus Medicatus Bertling Gesellschaft Fur Molekulare MedizinDevice for receiving and discharging a given amount of liquid
US8668552 *Feb 22, 2013Mar 11, 2014Boaz Barry GromanMethods of making micro-abrasive blasting device for dental applications
U.S. Classification73/864.2, 222/478, 73/864.3, 210/446, 222/189.6, 215/6, 422/922, 422/509
International ClassificationB01L3/02
Cooperative ClassificationB01L3/0213, B01L3/021
European ClassificationB01L3/02C1, B01L3/02C