DE2220305A1 - centrifuge - Google Patents

Description

Patent Attorneys 13 5 ^ O Dr. Μ / τ

Dipl. Ing. C. Wallach

Dipl. Ing. Θ. Cook 2 5

Dr. T. Kaibach
8 Munich 2
Kaufingerstr. 8, Tel. 240275

Beckman Instr uments ,, 1η © ₀ · ₀ Ppa, lQgfe®m _n © al.o. _P.

(UNITED STATES)

Centrifugal reo

The invention relates to allgoiaoisi E © u ^ s "lSviQowi tamd a switch arrangement; suss? TUiatosplb ^ ookiasag dos ³ Säftafaste <3οσ? Drive energy for a ^ <^ ft rä ^ goals'® $ 2? ₀ » sb Iboä • ös ten excessive rotorsehwisagisimgosB. u®m R © t © ^ nmlcmix sta end »

Occasionally fce «ai θ © tjiHasOSKfl üoq

au eine Schwimguiigenisigtaiag üqb MsrS © ^ ^ b Qoäiao tationsachse baw ^ su -AbwolokuaEagGja voiqi dioooK ³ Δ © £% οο _ο like HotorachwlsagusEgeia tsrcrfeosa, äa QllgOEJOäjaQjm at Ta doaja? gen speeds EesQ-Silotiaaäßassa ^ ®üow 3) 5? Oa "GTmsac <EO rotor by was" © mates ⁵ © k ^ itissFac it comes to aucli eiaes · ^ © ^ © ^

liable or unrelated «hiBfiSig05? VoiS "äo ± lw £ iQ © los ³ JPa in the various®» «» v®sa- ύΟΏ g © üa ^r ö5? Ä.i? T! 2goBiis ⁵ @ ⁱ S © s sample containers «The Aassaal

can be used by Rotor ski kotos' xros-OeSaioifloEa QOaSi ₀ Jo iaa © 3ä.

the dimensions of the rotor _P ¹ OBoI aiaoSa '^ © sü SOiafe-äffnaßo c ©' centrifuge, depending on the lowercM®iiIicJaea ligoaselaiG ^ om ύοϊ ?.

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Drive trains and / or tolerances. Whatever the cause of such vibrations, they must in any case to avoid damaging the rotor and for the safety of the operator.

A method for solving such a problem consists in - d & 3 mar, ei »β stabilization device, which - at low speeds, ■ comes into engagement with the motor if there is a risk of excessive rotor wobbling · A typical stabilization device of this type is described very much in the IFS patent.

Another, in US Pat. No. 2,895 "023-

acf ^ riebenas procedure consists in the fact that "E, t © riiai'b - of the centrifuge motor" a microswitch is arranged i UeT T © R sdnem vtar-divisible rod is operated, wel char bsi excessive. ·. "rotor vibrations in (with regard to the Rotatiiistsachsi; ä®s Slotors) radial direction outwards .to E ± 3, t $ Ti, ££ a? ± f ä «ta Wikrcgetealter is pressed and hereiiurcfe alf.- Strosauftiiir srüs ^ itriöbsiaotor interrupts

sZ'StTitge scarf ^ Φ ^ -Λϊ / δΊ'-αίΐί.ί. ■ · ;. 1st ain special on Z # iitrirugei * rahEie.si ar- ^ u ^ dKe-sfo »spider for mounting micro switch β ηηύ dos ' S-st-Ktigvinga partly (ie the

bbare »rod} ^ τ £ 'ύτά & τ! ± α ^ * Biese rather bulky E & lt & TunQ " vsrte-d ^ rt vsxd complicates the centrifuge-

Ihsrclx the Vorliöffaßä "Sri 'charge" is a simple introlI ^ orriefeitt "g xuv shutdown of the Lei to the eating

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will. The safety device should in a simple manner, without dismantling and remodeling, to compensate » borrowed different rotor dimensions and different Centrifuge drive gear to be adjustable and adaptable.

For this purpose, a centrifuge having a rotor and-a drive device-for rotating the rotor at predetermined speeds according to the invention labeled in · Seiehnet dUrd ^ ^ine arranged rotor exclusively at the and-held shouldered actuator and bottom by a 'in Spacer of the Peripheral part of the rotor and arranged in the vicinity of the normal movement path of the actuating device electrically in a circuit with the drive device switched switch device in such a way that in the event of excessive rotor vibrations from its normal axis of rotation, the actuating device comes into engagement with the switch device, whereby the electrical circuit is opened and the Power supply to the drive device is interrupted »

According to a preferred embodiment, provision can be made eein that the actuator is one in one Radially extending recess in the lower circumferential region of the rotor and a tubular housing has adjustable set screw inserted in an internally threaded bore at the outer end of the tubular Housing is arranged. The switch device may be adjacent to the normal path of travel of the operating device arranged movable element, for example an ejector pin.

2 0 9 8 A 67012 0

As soon as the rotor oscillates excessively or too begins to wobble, hits the adjustable adjusting screw in their trajectory on the moving element of the switch device, creating the electrical circuit opened and the power supply to the rotor drive is interrupted and the rotor rotation is ended.

In the following embodiments of the invention are described with reference to the drawing; in this show

1 shows a sectional side view of a centrifuge device according to an embodiment the invention}

Fig. 2 in an enlarged horizontal sectional view along the section line 2-2 in Fig. 1, the actuating device according to the invention)

Fig. 3 is a circuit diagram of the circuit containing the switch and the drive device}

FIG. K shows a schematic representation of an alternative embodiment of the switching device.

In the drawing, 1 is a typical centrifuge rotor with several at equal circumferential distances over the Rotor 10 distributed recesses 11 serving to accommodate sample containers. The vertically extending. Full is stored in an axle or pivot bearing 13 and can be driven by an electric motor (not shown) via a suitable drive gear. On his The rotor has a base opening i4 on the lower end face

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on which the upper Eade of Foil © 'contributes 12 nimfeiaEsn ^ ο Bio shaft further buckets Siesasaei & te & SQtoia iJaat ^ aslbssaisfoffii or · bolts i € - "eggs · sreiEa ikatei @ 1s> gQäsigß ^ä ai ⁴ £' EEaI ¹ O © isaoB ata 2ag> jp®sa attached to rotor 10 ? «B © 2s © ia H? -SHbOS

■ -The- rotor kasm isa des ³ goix®iia3, 'öosa vacuum chamber- in- © Ssl © ss®sa soiEi ₀ slosOia B © @ Zso2 ■ making the Ε © ΐ @ 2Ρ0 abBaoiaeibaE ³ äaöo- -Bio dung 13-der · ■ Aissklo.ianag hanss. am üqi? TmsatQa ³ Om Uasseteuag der · VakuiMBicamBer sltijola oäffioo BosskSgo SΌ Ί ^ οίΌο ^ ίΙβ ^ '- ZwI »Chen der - Wandtzsig 1f rasa ©} eloa · / isliaollagos'""3 3- •« I-a ¥ akuaEi € .lit g0öOil 22 cmc © scsä © dos ³ © ii das- darcla © äae © SuaeHsSOelOE ¹ S3 Nä'S soiaoiTi i »· BielitangsöiSig ^ iiTS ¹ Oa ¹ S <ioa üsaliogosaslGSi just kept wisr-d _e

Gate direction ' points © äso ESo ^< öS, ⁱ Sä, g2n®ßo ^v 7 © E ³ E ⁵ ä <3Ssi; iS5ao sasa <S o Schal-feervorrichtsä ^ g StSiP ₀ «3Ίο αϊ ο © aaooo ^ 33S ³ QSa släo B SBiffen »20 IiZIf ₁₅ 4 © feesQäelüaOö o'lmuo Mo g% 0 ±» t · on a | "/ @ m dos

teag g © οεΐΐβθ © Σ? (δπιο · οο © oüiQ © oäsos ¹ iisao ^ SS

verlaufesidiia Drafet! © ctej? AEaQvJOSPiO ¹ OaS ¹¹ O Q2, c ^ aao oäiaoB goo ueteit elektrieeiies Lcä ¹ OoE = GQv? O5? Äaa at3 <? _o Ufi <s ooäsaoB Bad · - ' approaches the pen - &"8 -äa oäsos? fö ^ oä'ÖGsa EÄai? Qsa« äos = • eite a » Bolaesis 46 ₀ e3oa ^s ooäsao ^c i? ooäi3o cea eOoa ³ Säa { 3ß) kj is attached- «Im s © iEä © Eä © ibosOsa Bsöo Os-IqO ¹ O <äos? © ^ I against an insgeeaEat ^» SBs- ^ Aq ßofe @ gosao © i au · Federmetalis öas ®l «e laö ©

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is under- <äer · Rxngpl & tvt kj and is in contact with a ÄK & iiLltsßbGlaseE- 4 £ «BeE- metal strip 42 is sandwich-shaped Ewisshea ά <& τ underside of the ring plate 43 and an X & GüeifM octe 44 clamped and-is thus in its position & Itesii-- Β : 1ΐ, - lower bath, the connecting bolt 46 and 48 »inä dcrelv jresignet © Laituagen in series with a- (not

tvimh for is: i Uasia ^ i / J ^ * Kötor »10 supplies,

SiäKv Ä:, CiTdii, -assi:; · air "/ binding of the switch device 20 sjis ϊί «ΐπ · 3ΐ. JoraEtri «^ ie ^ shaeiatic in Fig. 3

.? ali stands with changed

tsl fachung a ge gear- 52- in; Isr- S.ir ': ^ T ϊΰ * the connection sswi-

i7. £ ^: -. ' ⁵ tiü3? -U: ⁱ ? - ^^ i: -. Lines - 54 takes place -j't; v ^ 'g3V * f; i0cri :: «a starter 53 · Der An-2» «fi« S' -Γ ^; : * l · ¹ : Jt.-i; -. . "- ϊϊ :,> v ^ 3Biii? - 7oS. Elderly circle 56, who in the g®« -

iSsa Motors 51 causes. ! it »Circuit 56, DER i go break the Lei-motor 51 abge ~

. α Λ ·;

,, \ .i. ., _; ... -, as best from * .. '-.- ΓΙ "div r«'"^ ÖTMiges housing 21

mii Ιΐίώ ": ^ä τ« ** # j · »" ^f i ~ * Iff "** ^ie #m internal thread of a ; "~ * · - '" f »· **' ^! 8 Rotorkörpsra 10 auf. ^ J ^r r! * Tj5. *« T ^l üifi * '"j tubular OehlLu-

tee - * it - * »j *> * »H <-fei-uii ,; ' ** «ait internal thread, ν · 1οάϋ el- <"8χ # 1« st »>. * · *» * H aJ c * St- * screw © 25.

As from the case of the relativeia, mutual arrangement

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The switch device 40 and the actuating device 20 can be seen, if excessive rotor vibrations or deviations from the normal axis of rotation occur, the movement path of the adjusting screw 25 hits the ejector pin 4i. Under these circumstances, the adjusting screw 25 pushes the pin k1 out of the contact position with the spring 42, whereby the electrical circuit is opened and the power supply to the drive motor is interrupted With the breaker device kO , the operator can disregard various amounts of rotor vibrations.In other words, the closer the adjusting screw 25 is initially set to the ejector pin 41, the smaller the rotor vibrations required to interrupt the electrical circuit, and vice versa, the greater the distance with respect to the pin * f 1 to which the adjusting screw 25 is initially set, the greater the rotor oscillation required to break the electrical circuit Or dimensions and / or different centrifuge drive gears can be set by simply changing the position of the adjusting screw 25 «

In the embodiment described above an adjustable set screw is provided; however, any other suitable adjustable device can of course be used as the actuating device for the purposes of the present invention. For example, screw caps, bolts or the like can

209846/0120

The same can be used instead of the adjusting screw 25, or the tubular housing 21 itself can serve as an actuating device for triggering the pin 4t

The adjusting screw 25 can have a cylindrical bore so that the safety and protection control device according to the invention can be combined with a mechanical system for switching off the excessive speed, as described, for example, in US Pat. No. 2,666,572. In such a typical mechanical overspeed shutdown system, it is provided that a pin or tenon breaks under the action of shear forces as soon as the rotor exceeds a predetermined speed; the broken pin comes outwardly through an axial bore into engagement with an ejector pin, whereby the power supply to the drive motor is interrupted. By combining the adjusting screw actuating device according to the invention with such a shear bolt actuating device, the centrifuge system can be secured against both excessive rotor oscillations and excessive speeds.

In Fig. 4, an alternative embodiment of the switch device is shown; this consists of a rotary head unit _t which can be indexed four times before a snap wire 49 has to be replaced. In this embodiment, four elongated base pins 46 made of an electrical conductor material are arranged on a circular plate 45 made of an insulator material along its circumference and at equal circumferential intervals. An electrically conductive central support part 47j which is arranged in the axis of rotation of the plate 45,

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carries an electrically conductive circular disk 48 at its upper end · between each base pin 46 and the circular disk 48 there is a snap wire 49 nested. are characterized by (a non-illustrated} lines in a elektrischen- circuit with the rotor drive vejrbusadesso Once in Operation- a snap wire 49 d © i? adjusting very be on "25 detects wurde- and thereby the electric © concerning the interim end base pin 46 was interrupted -and- the conducting plate 48 _e is the aggregate into its next position of the nächstfolgende- snap wire · 49 with the ³ direction 4θ · cooperate may "with Help © eiaer - dtorasrfei gen rotary head assembly DI® Bedienungeporson -worn dew necessity is relieved, having to replace the Anasves> fes ° · »pin · every time when knocking out a throwing pin 41

- The invention was described above on the basis of a th -Koastriikti® »serving as an exemplary embodiment. * described - but it can be of course be modified ± n manHigfaetäen details "without this the scope of the invention" So could © «i» games, the turret assembly Fi ^ "will leave provided 4 with a be arbitrary number of ejector 4i turn®

Patent requirements » i

209848/0120

Claims (2)

Claims 1. Centrifuge with a centrifuge motor and a drive device for rotating the rotor at predetermined speeds »marked lehne t by an actuating device (20) arranged and supported exclusively on the rotor (11) and by an actuating device (20) at a distance from the lower peripheral part of the rotor and in the proximity of the normal movement path of the actuating device (2O) arranged, electrically switched in a circuit with the drive device switch device (4O, hl) such that in the event of excessive rotor vibrations from its normal axis of rotation, the actuating device (20) engages the switch device (40, in ), whereby the electrical circuit is opened and the power supply to the drive device is interrupted 2. Centrifuge according to claim 1, characterized in that «the actuating device (20) is one in one radial recess (22) in the lower circumferential area of the rotor (11) arranged tubular housing (20, 21) and an adjustable adjusting screw (25) which is arranged in an internally threaded bore at the outer end of the tubular housing (21). 3 · Centrifuge according to claim 2, characterized in that the switch device has a base plate (** 3) made of an insulating material, a screw (k6) arranged in this base plate (43) with a wide groove, an electrical 209846/0120 trically conductive spring part (42) "which is fastened with its one end to the base plate (30)" as well as an electrically conductive pin (4i) ₉ between the screw (46) and the other end of the electrically conductive spring part (42 ) is held and its lower end rests in the wide groove of the screw (46) - while its upper end is in contact with the spring part - (42) and - an electrical circuit closes _B - whereby the pin (4i) in the event of excessive rotor vibrations - knocked out by the adjusting screw (25) and the electrical circuit can be interrupted » ■ 4. Centrifuge according to one or more of the preceding claims, characterized in that the position of the adjusting screw can be adjusted to change the distance between the adjusting screw (25) and the launcher pin (4i) to compensate for different amounts of rotor oscillation. 209846/0120 Al Blank page