US3815790A - Precision liquid pipetting devices - Google Patents

Precision liquid pipetting devices Download PDF

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Publication number
US3815790A
US3815790A US00289996A US28999672A US3815790A US 3815790 A US3815790 A US 3815790A US 00289996 A US00289996 A US 00289996A US 28999672 A US28999672 A US 28999672A US 3815790 A US3815790 A US 3815790A
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US
United States
Prior art keywords
pipette
barrel
plunger
stop
pipetting device
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00289996A
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English (en)
Inventor
D Allen
T Lee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
KENSINGTON SCIENT CORP
KENSINGTON SCIENTIFIC CORP US
Baxter International Inc
Original Assignee
KENSINGTON SCIENT CORP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by KENSINGTON SCIENT CORP filed Critical KENSINGTON SCIENT CORP
Priority to US00289996A priority Critical patent/US3815790A/en
Application granted granted Critical
Publication of US3815790A publication Critical patent/US3815790A/en
Priority to DE2456049A priority patent/DE2456049C3/de
Assigned to SMI ACQUISITION CORPORATION, A DE CORP. reassignment SMI ACQUISITION CORPORATION, A DE CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SCIENTIFIC MANUFACTURING INDUSTRIES,
Assigned to AMERICAN HOSPITAL SUPPLY CORPORATION, reassignment AMERICAN HOSPITAL SUPPLY CORPORATION, ASSIGNMENT OF ASSIGNORS INTEREST. EFFECTIVE DATE JULY 3,1983 Assignors: SMI ACQISITION CORPORATION
Assigned to BAXTER TRAVENOL LABORATORIES, INC. A CORP. OF DE reassignment BAXTER TRAVENOL LABORATORIES, INC. A CORP. OF DE MERGER (SEE DOCUMENT FOR DETAILS). EFFECTIVE ON 11/25/1985 ILLINOIS Assignors: AMERICAN HOSPITAL SUPPLY CORPORATION INTO
Assigned to BAXTER INTERNATIONAL INC. reassignment BAXTER INTERNATIONAL INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE ON 10/17/1988 Assignors: BAXTER TRAVENOL LABORATORIES, INC., A CORP. OF DE
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B01L3/0217—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type
    • B01L3/0224—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type having mechanical means to set stroke length, e.g. movable stops
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F11/00—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it
    • G01F11/02—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement
    • G01F11/04—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement of the free-piston type
    • G01F11/06—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement of the free-piston type with provision for varying the stroke of the piston

Definitions

  • This invention relates generally to precision liquid pipetting devices and more particularly to improved means for adjusting the stroke of and calibrating the capacity of pipetting dispensers.
  • the principal object of this invention is to provide improved means for calibrating the volumetric capacity of a pipetting dispenser with a reproducible high degree of accuracy.
  • Another object of this invention is to provide simple means for selectively varying the volume of liquid dispensable from a micropipette of a particular size.
  • FIG. I is an overall view of one embodiment of precision pipetting device employing a disposable pipette of relatively large diameter
  • FIG. 2 illustrates another embodiment of precision pipetting device which employs a disposable micropipette of much smaller diameter
  • FIG. 3 is a cross-sectional view of the barrel and plunger assembly of the pipetting device of FIG. 1;
  • FIG. 4 is a cross-sectional view of the end of the barrel of the pipetting device of FIG. 3 with a different end cap in place;
  • FIG. is an end view of the cap ends of the pipetting devices of FIGS. 1 and 2;
  • FIG. 6 is a cross-sectional view of the calibration assembly of the pipetting device of FIG. 2;
  • FIG. 7 is a cross-sectional view of an alternate end construction for the pipetting device of FIG. 2;
  • FIG. 8 is a cross-sectional view of the calibration assembly of the pipetting device of FIG. 1.
  • This invention relates to improvements in precision pipetting devices of the type generally disclosed in M. E. Drummond, et al. US. Pat. No. 3,606,086 issued Sept. 20, 1971 for Microdispensing Device.
  • the devices include an elongated barrel 1 and a disposable pipette demountably mounted on the barrel, such as the extruded plastic pipette 2 of relatively large diameter illustrated in FIG. 1 or the smaller precision glass micropipette 2' illustrated in FIG. 2.
  • a reciprocable plunger 3 carried in part within the barrel 1 has one end within the pipette to draw liquid into and to dispense liquid from it.
  • Each of the described embodiments of barrel 1 has an interior bore into which the plunger 3 passes and is affixed to a plunger holder 4 at one end.
  • the coil spring means 5 within the bore of the barrel seats at one end against the barrel itself and at the other end against a seat 6 on the plunger holder, for example, to bias the plunger toward the withdrawn end of its stroke as is shown in FIGS. 3 and 4.
  • These threaded end caps 7, 7' have a generally circular head 8 substantially larger in diameter than the barrel 1 which is flattened as at face 9 shown in FIG. 5 to prevent roll of the pipetting device when it is resting upon a generally horizontal surface.
  • Each end cap 7, 7 also has a shoulder 10 spaced from its threads toward the coil spring means against which the plunger holder seat 6 abuts as the spring means biases the plunger toward the withdrawn end of its stroke.
  • a button head 11 threads into the remote end of the plunger holder 4 for manipulation of it. The thumb or forefinger of the user presses upon this button head and simultaneously pulls against the head 8 of end cap 7, 7'. etc. to extend the plunger 3.
  • the bias coil spring means 5 returns the plunger 3 to the withdrawn end of its stroke.
  • the embodiment of dispenser illustrated in FIG. 1 includes a plunger 3 which carries at its free end a semiresilient tip 15 which is substantially larger in diameter than the plunger and flexibly embraces the interior walls of the pipette 2 to force fluid from or draw fluid into the pipette.
  • a similar construction is shown in FIG. 6 in the tip 15' of the other embodiment of the invention.
  • the precision micropipette 2 can be formed with an internal diameter so precise that for small diameters the plunger 3 may be deployed within it without any tip 15' as is shown in FIG. 7.
  • the device of FIG. 1 has a pipette stop 20 mounted adjacent to the pipette-end of the barrel which is adjustably positionable along the axis of travel of the plunger.
  • the pipette stop 20 as shown in FIG. 8 comprises a hub 21 with an interior bore 22 which slides upon a cylindrical tip 23 of substantially the same diameter which protrudes from that end of the barrel 1 and sleeves over reciprocable plunger 3.
  • Set screw 24 in the hub 21 of the pipette stop 20 can be tightened against cylindrical tip 23 to position the stop 20 at any point along it.
  • a smaller diameter sleeve portion 25 of the stop 20 carries the flanged end of plastic pipette 2 press fit upon it with its flange 26 seated against hub 21.
  • the structure of the dispenser embodiment of FIG. 2 is similar in function.
  • the pipette stop 20 has a bore for the plunger 3 which is smaller than the diameter of the pipette 2' that mounts at the end of the barrel.
  • the stop 20' is adjustably positionable along the axis of travel of the plunger 3 by shifting its position within a cylindrical bore 28 in the end of barrel 1 and by holding it there with set screw 24'.
  • the pipette 2 seats against the pipette stop 20 and is held against it by a knurled collet 30 having female threads which thread upon a male threaded portion 31 of the barrel 1.
  • the precision pipetting dispensers of this invention provide the user with a means for precisely measuring and dispensing volumes in the order from I to I00 lambda or larger. They also provide a given dispenser with a variety of stroke lengths by an appropriate series of interchangeable end caps 7, 7', etc. Accuracy and reproducibility in the order of :1 percent is easily attained.
  • the dispenser is easily calibrated by placing in either of pipettes 2 or 2' a calibration tool which is nothing more than a wire or rod of predetermined length, loosening the set screws 24, 24 and in the embodiment of FIG. 2 loosening collet 30 also.
  • a plunger carried in part within the barrel and reciprocable with a predetermined stroke within the pipette to draw liquid into and to dispense liquid from the pipette
  • the improvement comprising a pipette calibration stop mounted adjacent said end of the barrel and being adjustably positionable along the axis of travel of the plunger, such that the pipette can be adjustably positioned with respect to the stroke of said plunger, and
  • a plunger carried in part within the barrel and reciprocable with a predetermined stroke within the pipette to draw liquid into and to dispense liquid from the pipette
  • a pipette calibration stop mounted adjacent said end of the barrel and being adjustably positionable along the axis of travel of the plunger such that the pipette can be adjustably positioned with respect to the stroke of said plunger;
  • each of the series having a shoulder spaced a different distance toward the spring means and by abuttment selectively limiting the travel of the plunger at the withdrawn end of its stroke.
  • end cap is generally circular with a diameter greater than the barrel and has a flattened face for preventing roll of the pipetting device when resting upon a generally horizontal surface.

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Clinical Laboratory Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Devices For Use In Laboratory Experiments (AREA)
US00289996A 1972-09-18 1972-09-18 Precision liquid pipetting devices Expired - Lifetime US3815790A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US00289996A US3815790A (en) 1972-09-18 1972-09-18 Precision liquid pipetting devices
DE2456049A DE2456049C3 (de) 1972-09-18 1974-11-22 Präzisions-Pipettiervorrichtung für Flüssigkeiten

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US00289996A US3815790A (en) 1972-09-18 1972-09-18 Precision liquid pipetting devices
DE2456049A DE2456049C3 (de) 1972-09-18 1974-11-22 Präzisions-Pipettiervorrichtung für Flüssigkeiten

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US3815790A true US3815790A (en) 1974-06-11

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DE (1) DE2456049C3 (de)

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3921864A (en) * 1972-09-22 1975-11-25 Dawes Ernest Frederick Syringes for making precision volume measurements
FR2305713A1 (fr) * 1975-03-25 1976-10-22 Faure Jean Distributeurs de volumes mesures de liquides
DE2633530A1 (de) * 1975-07-25 1977-02-03 Pasteur Institut Vorrichtung zur aufnahme und/oder abgabe kleiner dosierter fluessigkeitsmengen
FR2324366A1 (fr) * 1975-09-18 1977-04-15 Labora Mannheim Gmbh Pipette de laboratoire perfectionnee
US4020698A (en) * 1974-10-29 1977-05-03 Marteau D Autry Eric Pipette which may be calibrated
US4098125A (en) * 1977-03-30 1978-07-04 Lee Thomas E Adjustable volume pipetting device
FR2383704A1 (fr) * 1977-03-15 1978-10-13 Labora Mannheim Gmbh Pipette a main
US4140488A (en) * 1977-09-06 1979-02-20 Hycel, Inc. Sample liquid transfer means in an automatic chemical testing apparatus
US4141469A (en) * 1977-05-02 1979-02-27 Lee Thomas E Microdispensing dilution system
US4165646A (en) * 1978-07-26 1979-08-28 Shapiro Justin J Adjustable micro-dispensing liquid pipet
US4178803A (en) * 1976-03-01 1979-12-18 Lee Thomas E Pipetting devices
US4249419A (en) * 1979-01-05 1981-02-10 Thomas Bradley S Micropipette system
DE2705933C3 (de) 1976-03-01 1981-02-12 Thomas E. Lafayette Calif. Lee (V.St.A.) Pipettiervorrichtung
FR2489507A1 (fr) * 1980-08-27 1982-03-05 Hettich Andreas Pipette doseuse pour le debit de quantites predeterminees de liquide, procede d'etablissement de son organe d'entrainement et dispositif comprenant de telles pipettes
EP0076406A2 (de) * 1981-09-28 1983-04-13 Miles Laboratories, Inc. Analytisches Gerät und Verfahren
US4442722A (en) * 1982-02-23 1984-04-17 Beckman Instruments Inc. Plunger operated pipet
US4679446A (en) * 1985-09-09 1987-07-14 Baxter Travenol Laboratories, Inc. Multi-volume displacement pipette
WO1993011870A1 (en) * 1991-12-13 1993-06-24 John Poulten Limited Pipetter
US5725831A (en) * 1994-03-14 1998-03-10 Becton Dickinson And Company Nucleic acid amplification apparatus
US20030012079A1 (en) * 2001-07-16 2003-01-16 Stryker Instruments Bone cement mixing and delivery device for injection and method thereof
US6702990B1 (en) * 2002-02-05 2004-03-09 The Gel Company Spot picker
US20040267272A1 (en) * 2003-05-12 2004-12-30 Henniges Bruce D Bone cement mixing and delivery system
US20050128867A1 (en) * 2003-05-12 2005-06-16 Henniges Bruce D. Bone cement mixing and delivery system
US20120255378A1 (en) * 2011-04-07 2012-10-11 Medicatec Kabushiki-Kaisha Dispenser
US20130098864A1 (en) * 2010-07-26 2013-04-25 Lameplast S.P.A. Re-closable container for fluid products, particularly for medical, pharmaceutical and cosmetic products
USD731075S1 (en) * 2013-03-15 2015-06-02 Nalge Nunc International Corporation Pipette
US10343156B2 (en) 2013-03-15 2019-07-09 Nalge Nunc International Corporation Tapered pipette

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2029723B (en) * 1978-09-12 1982-12-01 Lee T Adjustable volume pipetting device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3334788A (en) * 1963-08-13 1967-08-08 Clark H Hamilton Syringe for chromatographic analyses
US3343539A (en) * 1964-10-22 1967-09-26 Moorhouse Turkey Hatchery Inc Piston type artificial insemination syringe having stroke adjusting means
US3366286A (en) * 1965-10-23 1968-01-30 Garth A. Kloehn High precision syringe
US3417904A (en) * 1966-01-11 1968-12-24 Fischer & Porter Co Syringe and method of making same
US3606086A (en) * 1969-11-10 1971-09-20 Drummond Instr Co Microdispensing device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3334788A (en) * 1963-08-13 1967-08-08 Clark H Hamilton Syringe for chromatographic analyses
US3343539A (en) * 1964-10-22 1967-09-26 Moorhouse Turkey Hatchery Inc Piston type artificial insemination syringe having stroke adjusting means
US3366286A (en) * 1965-10-23 1968-01-30 Garth A. Kloehn High precision syringe
US3417904A (en) * 1966-01-11 1968-12-24 Fischer & Porter Co Syringe and method of making same
US3606086A (en) * 1969-11-10 1971-09-20 Drummond Instr Co Microdispensing device

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3921864A (en) * 1972-09-22 1975-11-25 Dawes Ernest Frederick Syringes for making precision volume measurements
US4020698A (en) * 1974-10-29 1977-05-03 Marteau D Autry Eric Pipette which may be calibrated
FR2305713A1 (fr) * 1975-03-25 1976-10-22 Faure Jean Distributeurs de volumes mesures de liquides
DE2633530A1 (de) * 1975-07-25 1977-02-03 Pasteur Institut Vorrichtung zur aufnahme und/oder abgabe kleiner dosierter fluessigkeitsmengen
FR2324366A1 (fr) * 1975-09-18 1977-04-15 Labora Mannheim Gmbh Pipette de laboratoire perfectionnee
US4084730A (en) * 1975-09-18 1978-04-18 Labora Mannheim Gmbh Fur Labortechnik Measuring and pipetting device
DE2705933C3 (de) 1976-03-01 1981-02-12 Thomas E. Lafayette Calif. Lee (V.St.A.) Pipettiervorrichtung
DE2759305C3 (de) * 1976-03-01 1981-09-03 Thomas E. Lafayette Calif. Lee Präzisionspipette
US4178803A (en) * 1976-03-01 1979-12-18 Lee Thomas E Pipetting devices
US4154108A (en) * 1977-03-15 1979-05-15 Labora Mannheim Gmbh Hand pipette
FR2383704A1 (fr) * 1977-03-15 1978-10-13 Labora Mannheim Gmbh Pipette a main
FR2386022A1 (fr) * 1977-03-30 1978-10-27 Lee Thomas Dispositif de pipettage a volume reglable
US4098125A (en) * 1977-03-30 1978-07-04 Lee Thomas E Adjustable volume pipetting device
US4141469A (en) * 1977-05-02 1979-02-27 Lee Thomas E Microdispensing dilution system
US4140488A (en) * 1977-09-06 1979-02-20 Hycel, Inc. Sample liquid transfer means in an automatic chemical testing apparatus
US4165646A (en) * 1978-07-26 1979-08-28 Shapiro Justin J Adjustable micro-dispensing liquid pipet
US4249419A (en) * 1979-01-05 1981-02-10 Thomas Bradley S Micropipette system
FR2489507A1 (fr) * 1980-08-27 1982-03-05 Hettich Andreas Pipette doseuse pour le debit de quantites predeterminees de liquide, procede d'etablissement de son organe d'entrainement et dispositif comprenant de telles pipettes
EP0076406A2 (de) * 1981-09-28 1983-04-13 Miles Laboratories, Inc. Analytisches Gerät und Verfahren
EP0076406A3 (en) * 1981-09-28 1983-08-03 Miles Laboratories Inc. Analytical device and method, method for removing liquid from the outer surface of a pipette tube and apparatus therefore
US4442722A (en) * 1982-02-23 1984-04-17 Beckman Instruments Inc. Plunger operated pipet
US4679446A (en) * 1985-09-09 1987-07-14 Baxter Travenol Laboratories, Inc. Multi-volume displacement pipette
WO1993011870A1 (en) * 1991-12-13 1993-06-24 John Poulten Limited Pipetter
US5725831A (en) * 1994-03-14 1998-03-10 Becton Dickinson And Company Nucleic acid amplification apparatus
US20030012079A1 (en) * 2001-07-16 2003-01-16 Stryker Instruments Bone cement mixing and delivery device for injection and method thereof
US6547432B2 (en) * 2001-07-16 2003-04-15 Stryker Instruments Bone cement mixing and delivery device for injection and method thereof
US6702990B1 (en) * 2002-02-05 2004-03-09 The Gel Company Spot picker
US7677418B2 (en) 2003-05-12 2010-03-16 Stryker Corporation Bone cement cartridge with a releasably locked drive piston, the piston configured to be unlocked by a delivery device
US8721600B2 (en) 2003-05-12 2014-05-13 Stryker Corporation Delivery gun for dispensing bone bement from a cartridge, the gun having a multi-link linkage and capable of dispensing the cement at different flow rates
US20080025140A1 (en) * 2003-05-12 2008-01-31 Stryker Instruments Bone cement mixing and delivery system including a delivery gun and a cartridge having a piston, the delivery gun configured to release the piston
US7393342B2 (en) 2003-05-12 2008-07-01 Stryker Corporation Bone cement mixing and delivery system including a delivery gun and a cartridge having a piston, the delivery gun configured to release the piston
US20040267272A1 (en) * 2003-05-12 2004-12-30 Henniges Bruce D Bone cement mixing and delivery system
US20110085411A1 (en) * 2003-05-12 2011-04-14 Henniges Bruce D Cartridge in which bone cement is mixed and from which bone cement is delivered, the cartridge having a compressible blade with plural vanes
US8061887B2 (en) 2003-05-12 2011-11-22 Stryker Corporation Cartridge in which bone cement is mixed and from which bone cement is delivered, the cartridge having a compressible blade with plural vanes
US20050128867A1 (en) * 2003-05-12 2005-06-16 Henniges Bruce D. Bone cement mixing and delivery system
US8353622B2 (en) 2003-05-12 2013-01-15 Stryker Corporation Cartridge from which bone cement is discharged, the cartridge having a removably coupled nozzle
US20130098864A1 (en) * 2010-07-26 2013-04-25 Lameplast S.P.A. Re-closable container for fluid products, particularly for medical, pharmaceutical and cosmetic products
US8833576B2 (en) * 2010-07-26 2014-09-16 Lameplast S.P.A. Re-closable container for fluid products, particularly for medical, pharmaceutical and cosmetic products
US20120255378A1 (en) * 2011-04-07 2012-10-11 Medicatec Kabushiki-Kaisha Dispenser
US8758705B2 (en) * 2011-04-07 2014-06-24 Medicatec Kabushiki-Kaisha Dispenser
USD731075S1 (en) * 2013-03-15 2015-06-02 Nalge Nunc International Corporation Pipette
USD787698S1 (en) 2013-03-15 2017-05-23 Nalge Nunc International Corporation Pipette
US10343156B2 (en) 2013-03-15 2019-07-09 Nalge Nunc International Corporation Tapered pipette

Also Published As

Publication number Publication date
DE2456049A1 (de) 1976-07-15
DE2456049B2 (de) 1979-05-03
DE2456049C3 (de) 1980-01-03

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AS Assignment

Owner name: SMI ACQUISITION CORPORATION, A DE CORP.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SCIENTIFIC MANUFACTURING INDUSTRIES,;REEL/FRAME:004149/0597

Effective date: 19830701

AS Assignment

Owner name: AMERICAN HOSPITAL SUPPLY CORPORATION,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST. EFFECTIVE DATE JULY 3,1983;ASSIGNOR:SMI ACQISITION CORPORATION;REEL/FRAME:004277/0228

Effective date: 19840622

AS Assignment

Owner name: BAXTER TRAVENOL LABORATORIES, INC. A CORP. OF DE

Free format text: MERGER;ASSIGNOR:AMERICAN HOSPITAL SUPPLY CORPORATION INTO;REEL/FRAME:004760/0345

Effective date: 19870126

AS Assignment

Owner name: BAXTER INTERNATIONAL INC.

Free format text: CHANGE OF NAME;ASSIGNOR:BAXTER TRAVENOL LABORATORIES, INC., A CORP. OF DE;REEL/FRAME:005050/0870

Effective date: 19880518