US3832614A - Centrifuges - Google Patents

Centrifuges Download PDF

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Publication number
US3832614A
US3832614A US00061602A US6160270A US3832614A US 3832614 A US3832614 A US 3832614A US 00061602 A US00061602 A US 00061602A US 6160270 A US6160270 A US 6160270A US 3832614 A US3832614 A US 3832614A
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US
United States
Prior art keywords
rotor
centrifuge
signal
radiation
speed
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
US00061602A
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English (en)
Inventor
D Olliffe
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.)
MSE Holdings Ltd
Original Assignee
MSE Holdings Ltd
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
Priority to GB4044669A priority Critical patent/GB1325536A/en
Priority to DE19702037530 priority patent/DE2037530A1/de
Application filed by MSE Holdings Ltd filed Critical MSE Holdings Ltd
Priority to US00061602A priority patent/US3832614A/en
Priority to FR7029311A priority patent/FR2060598A5/fr
Priority to US05/462,540 priority patent/US3982162A/en
Application granted granted Critical
Publication of US3832614A publication Critical patent/US3832614A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04B—CENTRIFUGES
    • B04B13/00—Control arrangements specially designed for centrifuges; Programme control of centrifuges
    • B04B13/003—Rotor identification systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04B—CENTRIFUGES
    • B04B13/00—Control arrangements specially designed for centrifuges; Programme control of centrifuges
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P1/00—Details of instruments
    • G01P1/07—Indicating devices, e.g. for remote indication
    • G01P1/08—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers
    • G01P1/10—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers for indicating predetermined speeds
    • G01P1/106—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers for indicating predetermined speeds by comparing the time duration between two impulses with a reference time
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
    • G01P3/42—Devices characterised by the use of electric or magnetic means
    • G01P3/56—Devices characterised by the use of electric or magnetic means for comparing two speeds
    • G01P3/60—Devices characterised by the use of electric or magnetic means for comparing two speeds by measuring or comparing frequency of generated currents or voltages
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S388/00—Electricity: motor control systems
    • Y10S388/907—Specific control circuit element or device
    • Y10S388/911—Phase locked loop
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S388/00—Electricity: motor control systems
    • Y10S388/907—Specific control circuit element or device
    • Y10S388/921—Timer or time delay means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S388/00—Electricity: motor control systems
    • Y10S388/923—Specific feedback condition or device
    • Y10S388/933—Radiant energy responsive device

Definitions

  • An analytical centrifuge-to receive a plurality of different rotors each carrying a track with a segment having a light reflective property distinct from adjacent regions of the track and having a length along the track which is related to the maximum desired speed of the rotor, the centrifuge having optical sensing means for sensing said segment and a time comparator for comparing the duration of the signal obtained by the sensing means in each rotor revolution with a fixed time to sense when the maximum desired speed is reached.
  • Analytical rotors also carry a further track having distinct segments corresponding to respective compartments of the rotor and which are optically sensed to provide in conjunction with the signal obtained from the first-mentioned segment gating signals for examining selectable compartments of the rotor one-by-one.
  • FIGSb. A
  • This invention relates to centrifuges, and is particularly applicable to analytical centrifuges, i.e., centrifuges having an optical or other radiation system for sensing the radiation absorption properties of material whilst it is being centrifuged.
  • each rotor has a predetermined maximum speed of rotation defined by the length along an arcuate path around the rotor axis of a surface portion carried by the rotor, the centrifuge having sensing means for sensing said surface portion without contact therewith so as to produce a signal with a time duration which is a function of said length, and means responsive to the time duration of said signal to prevent increase in the speed of operation of the centrifuge when the time duration of said signal falls to a predetermined value.
  • said predetermined value may be preset so that it is equal to the duration of said signal when the rotor has reached a permissible maximum speed of rotation. In that case the length of said section, i.e., the angle it subtends at the axis, will be directly proportional to the desired maximum speed of the rotor.
  • the surface portion has a radiation affecting property different from that of adjacent surface portions on said arcuate path and the centrifuge has radiation directing or generating means for directing radiation at the path, the sensing means being radiation sensitive means for receiving radiation from the path and originating from the directing means.
  • optical radiation may be employed.
  • the above aspect of the invention is applicable generally to all types of centrifuge rotors, including analytical rotors having at least two, and preferably more than two, radiation transmissive compartments to receive samples. With such rotors, in each revolution a signal is obtained for each compartment and the problem is to separate out, and record if desired, the signal corresponding to just one compartment.
  • gating signals to select one of the compartments are obtained by sensing without contact with the rotor distinct portions carried by the rotor and corresponding to respective compartments, whilst the compartment selected is defined or identified by sensing a predetermined angular position of the rotor by means of said surface portion of the first aspect of the invention.
  • an analytical centrifuge for operation with analytical rotors with at least two compartments to receive samples
  • the centrifuge comprising a compartment examining system by which radiation can be passed through said compartments and the radiation transmitted through the compartments sensed and corresponding signals fed to a signal path, and sensing means for sensing without contact with the rotordistinct portions carried by the rotor and corresponding to respective rotor compartments, these means being connected to supply signals to control means of the examining system so that said signal path will carry a signal corresponding to the radiation passed through just one of the compartments, the sensing means also being effective to sense a predetermined an gular position of the rotor to define the compartment corresponding to said signal on the signal path.
  • the arrangement could be such that a signal will be produced in each revolution on each of two signal paths corresponding to respective ones of two compartments, the two signals being combined to produce a third signal defining the difference between the radiation absorption properties of material in said two compartments.
  • One of these two compartments may therefore contain a reference medium.
  • the sensing means is also operable to sense a predetermined angular position of the rotor to define to which distinct portion, and therefore to which compartment, the signal corresponds
  • the distinct portions can provide substantially identical responses at the sensing means yet a distinction can still be made between the compartments.
  • the portions may all have substantially the same light-affecting property, which is different from the light-affecting property of adjacent portions carried by the rotor in order to obtain distinct, but similar, signals in respect of each compartment.
  • the light-affecting properties could alternatively alternate from one distinct portion to the next.
  • the track mentioned above in respect of the first aspect of the invention can thus be utilised to sense a predetermined angular position of the rotor, for example by sensing the leading or trailing edge of the signal produced in accordance with the first aspect of the invention.
  • the rotor carries two arcuate tracks one having a plurality of distinct portions corresponding to respective compartments of the rotor and the other having a portion of a length along a circular path centred on the rotor axis which defines the maximum desired speed of rotation of the rotor.
  • the latter track may then be used not only for overspeed protection but also for the synchronisation of the multicompartment scanning in accordance with the second aspect of the invention.
  • FIG. 1 is a diagrammatic representation of an analytical centrifuge
  • FIG. 2 is a diagram representing reflective tracks carried on the underside of the rotor of the centrifuge of FIG. 1;
  • FIGS. 3a and 3b show wave forms of signals generated by the tracks shown in FIG. 2;
  • FIG. 4 is a block diagram of the overspeed control circuit for the centrifuge of FIG. 1;
  • FIGS. 5a and 5b are wave forms indicating the man net of operation of the circuit of FIG. 4;
  • FIG. 6 is a block diagram of a circuit for synchronising the optical scanning in the centrifuge of FIG. 1;
  • FIG. 7 is a diagram of the signals occurring in the circuit of FIG. 6.
  • FIG. 1 illustrates diagrammatically an analytical centrifuge comprising a centrifuge motor 1 supplied via a variable frequency 3-phase sinusoidal inverter 2 for speed control of the motor.
  • the motor shaft 3 is releasably coupled to a rotor 4 mounted within a vacuum tight enclosure 5 coupled to a vacuum pump or pumps 6.
  • the rotor 5 has a plurality, for example six, of compartments two of which are indicated at 7. These compartments are closed top and bottom by light transmissive closures and are adapted to hold light transmissive cells containing material to be analysed. This material will normally be in the form of a sample suspended in a carrier liquid and this carrier liquid will be contained by itself in one cell, which will act as a reference cell.
  • the enclosure 5 has light transmissive windows 8 and 9 through which the cells may be viewed successively during rotation of the rotor 4.
  • a light generating system 10 is arranged to direct light upwardly into the enclosure 5 and through successive cells, and a photodetector 11 is positioned to receive that portion of the light which has passed through the cells.
  • the centrifuge is also equipped with two arrangements 12 and 13 each containing a light source and a light sensor.
  • the light sources are arranged to direct light onto the lower surface of the rotor 4 and the light sensors are arranged to receive that light having been reflected from the rotor 4.
  • FIG. 2 is a diagram showing the pattern of reflecting and substantially non-reflecting surface portions which are provided on the lower surface of the rotor 4.
  • This pattern consists of two circular tracks concentric with the axis of rotation of the rotor, the inner track 14 consisting of a reflecting section 15 and a substantially non-reflecting section 16.
  • the length of the section 15 is directly proportional to the desired maximum speed of rotation of the particular rotor.
  • the arrangement 12 comprises a light source 17 directing its light onto the track 14 and a photo-detector 18 positioned to receive light reflected from this track.
  • the photodetector 18 will produce a signal in each revolution of the rotor which has a time duration which is proportional to the length of the section 15, and inversely proportional to'the actual speed of rotation of the rotor.
  • This signal is illustrated diagrammatically in FIG. 3b for a section 15 which extends for 270 about the axis of rotation of the rotor 4.
  • the second track 19 comprises six equal-length reflecting sections 20 spaced apart by six equal-length substantially non-reflecting sections 21.
  • the sections 20 have their centres on substantially the same radii as the centre lines of six respective compartments in the rotor.
  • the arrangement 13 comprises a light source 22 directing light onto the track 19 and a photo-detector 23 arranged to receive reflected light from this track.
  • the signal produced by the photo-detector 23 is indicated in FIG. 3a.
  • FIG. 4 indicates in diagrammatic form the overspeed control circuit.
  • the light sources 17 and 22 directing light via the rotor 4 to the photo-detectors 18 and 23, which may be photomultipliers.
  • the signals produced by the photomultipliers and indicated in FIGS. 3a and 3b are fed to amplifiers 24a and 24b.
  • the output of amplifier 24b is connected back to a lamp supply circuit 17a to vary the light level in a sense tending to maintain the amplitude of the signal of FIG. 3a substantially constant.
  • the output of the amplifier 24a feeds a pulse duration comparator 25 and a differentiating circuit 26, which latter circuit supplies a trigger pulse at the positive edge of the signal of FIG. 3b to trigger a pulse generator 27.
  • the pulse generator 27 supplies a reference pulse B of predetermined duration to the comparator 25.
  • a signal at the output 28 of the comparator is effective to cause disconnection of the supply to the motor 1 or otherwise to limit its speed.
  • FIG. 5a illustrates the conditions at the comparator whilst the rotor is being run up to speed. At A is indicated the pulse fed to the comparator via the amplifier 24a and at B is represented the reference pulse B produced by the pulse generator.
  • the pulse A has a longer duration than that of pulse B, indicating that the rotor speed is less than the permissible maximum speed; Uner these conditions, there will be no signal at the output 28.
  • the rotor speed increases, the length of the pulse A falls until it reaches that of the pulse B. Any further increase of the rotor speed will further decrease the duration of the pulse Ato give the condition illustrated in FIG. 5b, whereupon the comparator will issue an output signal at 28 which indicates that the rotor speed has increased above the maximum permissible speed. As indicated, this output signal will cause deceleration of the motor 1, for example by positive braking or merely by disconnecting its supply.
  • the amplifiers 24a and 24b also produce signals on lines 29a and 29b for synchronising purposes in the circuit of FIG. 6 which controls the optical scanning of the cells in the centrifuge rotor.
  • FIG. 6 illustrates a stepping motor 30 driven by a pulse generator 31 and stepping a rheostat 32 which supplies the 2: input of an x-y recorder 33.
  • the stepping motor 30 also controls the ultra-violet light generator which supplies ultra-violet light through the cells of the rotor 4.
  • the generator 10 produces a beam of elongate cross-section of ultra-violet light, the length direction of the cross-section extending at the cells in the peripheral direction in relation to the rotor axis. This beam is stepped radially along the rotor by means of the stepping motor.
  • the light from the generator 10 passes to a photomultiplier 11 having passed through the rotor cells.
  • the photomultiplier will produce six pulses relating to the respective cells and these pulses must be separated from one another.
  • the pulses are fed, via an amplifier 34, to two signal channels 35 and 36.
  • These channels contain respective gating and holding circuits including low-pass filters to form the average of the pulses received.
  • Each circuit is operated so as to process and pass-on a signal relating to only one of the six pulses occurring in any one revolution of the rotor.
  • the gating and holding circuits 37 and 38 are controlled by a counter having three bistable stages 39, 40 and 41 the outputs of which are connected to the circuits 37 and 38 via a decoder and respective sixposition selector switch pairs 42 and 43.
  • the setting inputs of the bistable stages are connected to the light sensor 23 via line 29b and a monostable circuit. The stages will therefore receive six pulses per revolution.
  • the reset inputs of the bistable stages are each fed from the line 29a of FIG. 4 via a monostable circuit and are thus fed with one pulse per revolution.
  • each revolution of the rotor the six fixed contacts of each selector switch of the pairs 42 and 43 will each receive one of six successive pulses from the counter 39, 40 and 41.
  • the moment at which each of these pulses occurs is the moment at which the corresponding one of the rotor cells is passing the scanning position of the ultra-violet scanning system 10 and' 11.
  • the pulses occurring at points in the circuit of FIG. 6 are illustrated in FIG. 7.
  • each signal channel 35 and 36 contains a circuit 44, which produces an output signal representing the logarithm of its input signal, and leads to a circuit 45 which forms a signal representing the difference between its input signals.
  • a device 46 is connected between the circuit 45 and the recorder 33 to enable the scale of the recorder to be expanded and contracted as desired and to enable the y-origin to be chosen at will.
  • the pulses of FIG. 3a have a repetition rate proportional to actual rotor speed and may thus be used to act upon the inverter 2 to maintain the rotor speed substantially at a presettable speed.
  • a centrifuge operable with a variety of rotors, with e'ach rotor there being associated a maximum speed of rotation defined by an element carried by a respective one of said rotors, the centrifuge having means for sensing said element to prevent increase in the speed of rotation of said rotor when the maximum speed is reached, the improvement which resides in said element being a surface portion having, along an annular path centered on the axis of said rotor, a length defining the maximum speed and a property along its length which distinguishes said surface portion from the remainder of said annular path; said sensing means being arranged to sense said property of the surface portion without contact with said rotor to produce a signal having a time duration which is a function of said length; and means for sensing when the time duration of the signal has fallen to a predetermined value.
  • centrifuge as claimed in claim 1, wherein said property is a radiation-affecting property different from that of said remainder of the annular path, the centrifuge comprising radiation directing means for directing radiation at said annular path, and said sensing means being radiation sensitive for receiving the radiation from said path and originating from said directing means.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Centrifugal Separators (AREA)
US00061602A 1969-08-13 1970-08-06 Centrifuges Expired - Lifetime US3832614A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
GB4044669A GB1325536A (en) 1969-08-13 1969-08-13 Centrifuges
DE19702037530 DE2037530A1 (de) 1969-08-13 1970-07-29 Zentrifuge, insbesondere Analysen zentrifuge
US00061602A US3832614A (en) 1969-08-13 1970-08-06 Centrifuges
FR7029311A FR2060598A5 (fr) 1969-08-13 1970-08-07
US05/462,540 US3982162A (en) 1969-08-13 1974-04-19 Centrifuges

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB4044669 1969-08-13
US00061602A US3832614A (en) 1969-08-13 1970-08-06 Centrifuges
US05/462,540 US3982162A (en) 1969-08-13 1974-04-19 Centrifuges

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US05/462,540 Division US3982162A (en) 1969-08-13 1974-04-19 Centrifuges

Publications (1)

Publication Number Publication Date
US3832614A true US3832614A (en) 1974-08-27

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US00061602A Expired - Lifetime US3832614A (en) 1969-08-13 1970-08-06 Centrifuges
US05/462,540 Expired - Lifetime US3982162A (en) 1969-08-13 1974-04-19 Centrifuges

Family Applications After (1)

Application Number Title Priority Date Filing Date
US05/462,540 Expired - Lifetime US3982162A (en) 1969-08-13 1974-04-19 Centrifuges

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US (2) US3832614A (fr)
DE (1) DE2037530A1 (fr)
FR (1) FR2060598A5 (fr)
GB (1) GB1325536A (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4296362A (en) * 1978-05-18 1981-10-20 Beasley Electric Corporation Motor having electronically switched stator field current and integral torque control
US4818922A (en) * 1986-10-22 1989-04-04 Allied-Signal Inc. Optical commutation for permanent magnet motors
US20020077240A1 (en) * 2000-04-11 2002-06-20 Kendro Laboratory Products, L.P. Method and system for energy management and overspeed protection of a centrifuge
US6616588B2 (en) * 2001-05-21 2003-09-09 Hitachi Koki Co., Ltd. Centrifugal separator with rotor identification
US20120076681A1 (en) * 2005-08-09 2012-03-29 The Johns Hopkins University Pneumatic stepper motor

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2559343C2 (de) * 1975-12-31 1983-10-06 Fa. Andreas Hettich, 7200 Tuttlingen Anordnung zur Erfassung einer maximal zulässigen Drehzahl eines auswechselbaren Rotors einer Zentrifuge
JPS6039089Y2 (ja) * 1982-02-17 1985-11-22 株式会社久保田製作所 ロ−タ種類自動判別装置
DE3301113C2 (de) * 1983-01-14 1985-01-10 Fresenius AG, 6380 Bad Homburg Verfahren und Vorrichtung für das Separieren von Medien
GB8324912D0 (en) * 1983-09-17 1983-10-19 Fisons Plc Magnetic device
HU192531B (en) * 1984-01-26 1987-06-29 Mueszeripari Muevek Lab Multifunctional centrifuge
US4551715A (en) * 1984-04-30 1985-11-05 Beckman Instruments, Inc. Tachometer and rotor identification apparatus for centrifuges
US4700117A (en) * 1985-05-31 1987-10-13 Beckman Instruments, Inc. Centrifuge overspeed protection and imbalance detection system
US4724317A (en) * 1985-12-05 1988-02-09 Baxter Travenol Laboratories, Inc. Optical data collection apparatus and method used with moving members
JPH0657325B2 (ja) * 1986-12-10 1994-08-03 イー・アイ・デュポン・ドゥ・ヌムール・アンド・コンパニー ロータ認識装置
SU1734865A1 (ru) * 1988-07-18 1992-05-23 Московское научно-производственное объединение "Биофизприбор" Устройство дл контрол центрифуги
DE4014431C1 (fr) * 1990-05-05 1991-07-04 Heraeus Sepatech Gmbh, 3360 Osterode, De
US5235864A (en) * 1990-12-21 1993-08-17 E. I. Du Pont De Nemours And Company Centrifuge rotor identification system based on rotor velocity
US5221250A (en) * 1991-01-07 1993-06-22 Beckman Instruments, Inc. Coding of maximum operating speed on centrifuge rotors and detection thereof
DE4208059A1 (de) * 1992-03-13 1993-09-16 Hermle Berthold Maschf Ag Zentrifuge
DE4419485C2 (de) * 1994-06-03 1997-02-13 Sigma Laborzentrifugen Gmbh Rotor für eine Laborzentrifuge
DE19503534A1 (de) * 1995-02-03 1996-08-08 Fresenius Ag Zentrifuge
US5714858A (en) * 1995-03-24 1998-02-03 Nuova M.A.I.P. Macchine Agricole Industriali Pieralisi S.P.A. Device for controlling and regulating the relative speed between rotary components interacting with one another respectively connected to the rotor and stator of an electric motor
US5948271A (en) * 1995-12-01 1999-09-07 Baker Hughes Incorporated Method and apparatus for controlling and monitoring continuous feed centrifuge
CN101268466A (zh) * 2005-07-19 2008-09-17 托马斯·C·汉森 切向制造系统
US7722562B2 (en) * 2006-03-02 2010-05-25 Tyco Healthcare Group Lp Pump set with safety interlock
US8021336B2 (en) * 2007-01-05 2011-09-20 Tyco Healthcare Group Lp Pump set for administering fluid with secure loading features and manufacture of component therefor
US7722573B2 (en) 2006-03-02 2010-05-25 Covidien Ag Pumping apparatus with secure loading features
US7763005B2 (en) * 2006-03-02 2010-07-27 Covidien Ag Method for using a pump set having secure loading features
US7927304B2 (en) * 2006-03-02 2011-04-19 Tyco Healthcare Group Lp Enteral feeding pump and feeding set therefor
US7560686B2 (en) 2006-12-11 2009-07-14 Tyco Healthcare Group Lp Pump set and pump with electromagnetic radiation operated interlock
US20080147008A1 (en) * 2006-12-15 2008-06-19 Tyco Healthcare Group Lp Optical detection of medical pump rotor position
SE535959C2 (sv) * 2010-01-29 2013-03-05 Alfa Laval Corp Ab System innefattande centrifugalseparator samt metod för kontroll av detsamma
US8154274B2 (en) 2010-05-11 2012-04-10 Tyco Healthcare Group Lp Safety interlock

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3462670A (en) * 1966-06-06 1969-08-19 Int Equipment Co Centrifuge and means to prevent overdriving its rotor
US3582699A (en) * 1969-06-12 1971-06-01 Damon Eng Inc Overspeed control for centrifuge

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1055971A (en) * 1963-03-01 1967-01-25 Mse Holdings Ltd Improvements in or relating to centrifuges

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3462670A (en) * 1966-06-06 1969-08-19 Int Equipment Co Centrifuge and means to prevent overdriving its rotor
US3582699A (en) * 1969-06-12 1971-06-01 Damon Eng Inc Overspeed control for centrifuge

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4296362A (en) * 1978-05-18 1981-10-20 Beasley Electric Corporation Motor having electronically switched stator field current and integral torque control
US4818922A (en) * 1986-10-22 1989-04-04 Allied-Signal Inc. Optical commutation for permanent magnet motors
US20020077240A1 (en) * 2000-04-11 2002-06-20 Kendro Laboratory Products, L.P. Method and system for energy management and overspeed protection of a centrifuge
US6679820B2 (en) * 2000-04-11 2004-01-20 Kendro Laboratory Products, Lp Method for energy management and overspeed protection of a centrifuge
US6616588B2 (en) * 2001-05-21 2003-09-09 Hitachi Koki Co., Ltd. Centrifugal separator with rotor identification
US20120076681A1 (en) * 2005-08-09 2012-03-29 The Johns Hopkins University Pneumatic stepper motor
US10024160B2 (en) * 2005-08-09 2018-07-17 The Johns Hopkins University Pneumatic stepper motor

Also Published As

Publication number Publication date
DE2037530A1 (de) 1971-02-25
FR2060598A5 (fr) 1971-06-18
US3982162A (en) 1976-09-21
GB1325536A (en) 1973-08-01

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