FI91043C

FI91043C - step pipette

Info

Publication number: FI91043C
Application number: FI931650A
Authority: FI
Inventors: Jukka Tervamaeki
Original assignee: Labsystems Oy
Priority date: 1992-04-13
Filing date: 1993-04-13
Publication date: 1994-05-10
Also published as: FI931650A; FI931650A0; FI91043B

Description

91043 i91043 i

ASKELPIPETTI TEKNIIKAN ALASTEP PIPETTE TECHNICAL FIELD

Keksintd liittyy askelpipetteihin, joilla mSnnallS sisMan-5 imetty neste voidaan annostella ulos useina pienempinå annok-sina.The invention relates to step pipettes with which mSnnallS sisMan-5 aspirated liquid can be dispensed in several smaller doses.

TEKNIIKAN TAUSTATECHNICAL BACKGROUND

Tunnetaan askelpipettejS, joissa on sylinterissS liikutel-lo tava manta, mannan varressa pituussuuntainen hammastanko, hammastankoon jousen voimalla nojaava iskuri seka iskurin kayttoelin, jonka avulla iskuri pakotetaan tyontamSSn ylos-vedettyS hammastankoa, ja siten my6s mMntSå, haluttu, mSnnan koko liikematkaa lyhyempi matka alaspain. Julkaisussa FI-25 60137 ja FI-77166 kuvataan tallaisia pipetteja, joissa on lisMksi hammasrattaan valityksellå månnan varteen yhdistetty tSytt6tanko, jota painamalla mSntS vedetaan ylSasentoonsa.Step pipettes are known which have a cylindrically movable Manta, a longitudinal rack with a manna arm, a striker resting on the rack by the force of a spring, and an actuator actuator by means of which the striker is forced to move a shorter, more or less, rack and pinion. FI-25 60137 and FI-77166 describe such pipettes which additionally have a filler rod connected to the piston rod by means of a gear, by pressing which the mSntS is pulled upwards.

Eraana ongelmana mm. edellS mainituissa askelpipeteissM on ollut se, ettS viimeinen ulosty6nnettåva annos jåS usein va-20 jaaksi, koska hammastanko ei pysty enaa siirtymåån koko ha-luttua matkaa.Another problem is e.g. In the above-mentioned step pipettes, it has been the case that the last dose to be delivered is often missed because the rack is no longer able to move the entire desired distance.

KEKSINNON YLEINEN KUVAUSGENERAL DESCRIPTION OF THE INVENTION

Keksinnon paatarkoituksena on aikaansaada painettavalla 25 tayttotangolla varustettu askelpipetti, jossa myos viimeinen ulosty6nnetty nesteannos on taysi. TSmS saavutetaan patentti-vaatimuksessa 1 esitetyin keinoin. Muissa vaatimuksissa esi-tetaån eraita edullisia sovellutuksia.The main object of the invention is to provide a step pipette with a printable filling rod 25, in which even the last dispensed liquid dose is complete. TSmS is achieved by the means set out in claim 1. Other preferred embodiments are set forth in the other claims.

Olennaista keksinnossa on jousen voimalla hammastankoon 30 nojaava iskuri seka iskurin jousen vapautusmekanismi, joka eståa iskuria tarttumasta hammastankoon, kun jåljella ei ole enåa tåyttS annosta ulostyonnettSvaksi.Essential to the invention is a spring-loaded striker resting on the rack 30 and a striker spring release mechanism that prevents the striker from engaging the rack when there is no more full dose left to be delivered.

KEKSINN6N erXXn SOVELLUTUKSEN YKSITYISKOHTAINEN KUVAUS 35 Seuraavassa keksinnon erSstå edullista sovellutusta selos- tetaan viela yksityiskohtaisemmin. Selostuksen piirustuksissa kuviot 1-3 esittMvat erastM keksinnon mukaista pipettiS toiminnan eri vaiheissa.DETAILED DESCRIPTION OF THE ERX APPLICATION OF THE INVENTION In the following, a preferred embodiment of the invention will be described in more detail. In the drawings of the description, Figures 1-3 show a particular pipette according to the invention at different stages of operation.

22

Pipetin pååosat ovat (kuviot 1) ontto, pitkånomainen kahva 1 ja sen alapååsså sylinteriosa 2. Sylinteriosaan on sovitet-tu måntå 3 liikkuvaksi sylinterisså 4. Sylinteriosan karki on kapeneva ja siihen on tarkoitettu kiinnitettåvåksi kårkisåi-5 lio nestettå vårten.The main parts of the pipette are (Fig. 1) a hollow, elongate handle 1 and at its lower end a cylinder part 2. A piston 3 is arranged in the cylinder part to move in the cylinder 4. The cylinder of the cylinder part is tapered and is intended to be attached to the tip.

Månnån 3 varren ylåpååhån on kiinnitetty annostelutanko 5. Se on sovitettu liukuvaksi kahvan pituussuunnassa sen toisel-la sivulla. Tanko 5 on kiinnitetty månnån 3 varteen kahvan keskelle ulottuvan ulokkeen 6 vålityksellå.A dosing rod 5 is attached to the top of the piston 3 arm. It is adapted to slide in the longitudinal direction of the handle on one side thereof. The rod 5 is attached to the piston 3 arm by means of a protrusion 6 extending in the middle of the handle.

10 Annostelutangon 5 ylåpååsså sen sisåånpåin olevalla sivul la on annosteluhammastus 7. Sen kanssa toimii iskuri S, joka on laakeroitu vipuun 9 pisteesså 10. Vivun 9 vapaa påå ulot-tuu kahvassa olevasta aukosta kahvan ulkopuolelle sen annostelutangon 5 puoleiselle sivulle. Vastakkaisella sivulla on is vivun 9 toinen påå laakeroitu kahvaan pisteesså 11.The upper side 1a of the dosing rod 5 has a dosing tooth 7 on its inlet side. It is operated by a striker S mounted on the lever 9 at point 10. The free end of the lever 9 extends from the opening in the handle outside the handle to its dosing rod 5 side. On the opposite side, the other end of the lever 9 is mounted on the handle at point 11.

Iskurin 8 alapååsså on teråvå kårki, joka tarttuu annoste-luhammastukseen 7, kun vipua 9 painetaan alaspåin.At the lower end of the striker 8 there is a sharp tip which engages the metering toothing 7 when the lever 9 is pressed down.

Iskuriin 8 liittyy myos iskurijousi 12, joka painaa isku-ria vasten annosteluhammastusta 7.The striker 8 is also associated with a striker spring 12, which presses the striker against the metering tooth 7.

20 Kun annostelutanko 5 nousee ylos, imee mantå 3 nestettå sisåån. Vivun 9 ja iskurin 8 avulla voidaan tankoa 5 ja siten myos måntåå 3 tyontåå alaspåin mååråsuuruisin askelin ja siten annostella sisåån imetty neste ulos pienempinå, mååråsuu-ruisina annoksina (kuvio 2).20 When the dosing rod 5 rises, it absorbs the liquid 3 into the mantle. By means of the lever 9 and the striker 8, the rod 5 and thus also the piston 3 can be pushed down in quantitative steps and thus the sucked-in liquid can be dispensed out in smaller, quantitative doses (Fig. 2).

25 Annostelutanko 5 vedetåån ylos tåyttotangon 13 avulla (ku vio 1) . Se on annostelutangon 5 suuntainen ja sijoitettu kahvaan vastakkaiselle sivulle kuin annostelutanko. Kummankin tangon 5 ja 13 alapååsså on toisiaan vastaan olevilla sivuil-la pituussuuntaiset samajakoiset hammastukset 14 ja 15 sekå 30 niiden vålisså kummankin kanssa rynnosså oleva hammaspyorå 16. Tåyttotangon 13 ylåpåå ulottuu kahvan ulkopuolelle. Nåin kun tåyttotanko 13 painetaan ala-asentoon, nousee annostelutanko 5 ylåasentoonsa. Vastaavasti kun annostelutankoa 5 painetaan alaspåin siirtyy tåyttotanko 13 ylospåin.25 The dosing rod 5 is pulled up by means of the filling rod 13 (Fig. 1). It is parallel to the dosing rod 5 and placed on the opposite side of the handle from the dosing rod. At the lower end of each rod 5 and 13, on opposite sides, there are longitudinally spaced teeth 14 and 15 and 30 between them, each with a ring gear 16 which rests with the upper end of the filling rod 13 and extends beyond the handle. Thus, when the filling rod 13 is pressed to the lower position, the dosing rod 5 rises to its upper position. Correspondingly, when the dosing rod 5 is pressed down, the filling rod 13 moves upwards.

35 Iskurijousen 12 (tåsså laakerointipisteen 10 ympåri sovi tettu V:n muotoinen lanka- tai lehtijousi) toinen påå on kiinni iskurissa 8 ja toinen, vapaa påå 17 nojaa tåyttotan-koon 13 siten, ettå jousi pyrkii painamaan iskuria påin annosteluhammastusta 7. Iskurijousen 12 vapautuselimenå on 91043 3 tåsså tåyttotangon 13 keskivaiheilla oleva kolo, lovi, reika tai tangon paå 18, joka toimii vaistonå jousen vapaalle påål-le 17. Vapaan paan 17 osuessa koloon 18 jousen 12 jannitys vapautuu.35 One end of the shock spring 12 (here a V-shaped wire or leaf spring arranged around the bearing point 10) is attached to the striker 8 and the other free end 17 rests on the filling rod 13 so that the spring tends to push the striker away from the dispensing spring 12. is 91043 3 here a recess, notch, hole or rod end 18 in the middle stages of the filling rod 13, which acts instinctively on the free end 17 of the spring 17. When the free end 17 hits the cavity 18, the tension of the spring 12 is released.

5 Vaiston 18 paikka tayttotangossa 13 on mååråtty siten, ettå jousen 12 påå 17 osuu koloon viimeisen tåyden annoste-luiskun aikana. Annosteluhammastuksen 7 ja iskurin 8 kårjen vålisen kitkan ansiosta ei iskuri kuitenkaan irtoa hammastuk-sesta 7 vielå iskun aikana, vaan vasta palatessaan takaisin ίο ylåasentoon (kuvio 3) .The position of the instinct 18 in the filling rod 13 is determined so that the end 17 of the spring 12 hits the recess during the last full dosing slide. However, due to the friction between the dosing tooth 7 and the tip of the striker 8, the striker does not disengage from the tooth 7 during the stroke, but only when it returns to the up position (Fig. 3).

Iskuriin 8 liittyy lisåksi irrotusjousi 19 iskurin irrot-tamiseksi hammastuksesta 7. Irrotusjousi 19 on vetojousi, jonka ylåpåå on kiinnitetty kahvaan iskurin 8 ylåpuolelle pisteeseen 20 ja alapåå iskuriin 8 epåkeskeisesti laakeroin-15 tipisteen 10 suhteen pisteeseen 21 siten, ettå palautusjousi pyrkii myos vååntåmåån iskuria irti hammastuksesta 7. Palautusjousi 18 toimii samalla vivun 9 palautusjousena.The striker 8 is further associated with a release spring 19 for releasing the striker from the toothing 7. The release spring 19 is a tension spring, the top of which is attached to the handle above the striker 8 at point 20 and below the striker 8 eccentrically with the bearing-15 from the toothing 7. The return spring 18 at the same time acts as a return spring of the lever 9.

Irrotusjousen 19 voima ei luonnollisestikaan saa olla niin suuri, ettå iskuri 8 irtoaisi hammastuksesta 7 viimeisen is-20 kun aikana kun jousen 12 påå 17 tulee koloon 18. Iskurin 8 ja hammastuksen 7 vålisen kitkavoiman mååråå ennen kaikkea mån-nån 3 ja sylinterin 4 vålinen kitka. Haluttaessa voidaan ir-toaminen iskun aikana eståå myos iskurin 8 kårjen ja hammastuksen 7 sopivalla muotoilulla.The force of the release spring 19 must not, of course, be so great that the striker 8 disengages from the toothing 7 during the last is-20 when the end 17 of the spring 12 enters the recess 18. The frictional force between the striker 8 and the toothing 7 is primarily between the piston 3 and the cylinder 4 . If desired, detachment during the impact can also be prevented by a suitable design of the tip and toothing 7 of the striker 8.

25 Iskurin 8 liikkeen alarajan mååråå kahvassa kiinni oleva rajoitin 22 (kuvio 2). Iskuri 8 ulottuu poikkisuunnassa annosteluhammastuksen 7 sivulle. Iskurin 8 tarttumiskohdan hammastuksen 7 mååråå hammastuksen 7 suuntainen sen sivulle sijoitettu sååtotanko 23. Sen alapåå on pyoristetty nokaksi 30 24, joka nostaa iskurin 8 irti hammastuksesta 7 iskurin ylos- menovaiheen aikana. Iskuria 8 alas painettaessa sen kårki painuu hammastukseen 7 heti nokan 24 alapuolelta.25 The lower limit of movement of the striker 8 is determined by the stop 22 attached to the handle (Fig. 2). The striker 8 extends transversely to the side of the metering tooth 7. The engagement point of the striker 8 engages the toothing position 7 with an adjusting rod 23 located parallel to the toothing 7. At its bottom, a cam 30 24 is rounded, which lifts the striker 8 off the toothing 7 during the stroke exit phase. When the striker 8 is pressed down, its tip is pressed into the toothing 7 immediately below the cam 24.

Annosteluiskun pituuden sååtåmiseksi on sååtdtanko 23 teh-ty pituussuunnassa siirrettåvåksi kahvan suhteen. Tangon 23 35 ylåpååhån on tåtå vårten laakeroitu sååtopyorå 25, jonka akseli kulkee tangon pituussuuntaisen uran poikki. Tanko 23 on lisåksi laakeroitu epåkeskeisesti pyoråån 25. Nåin pyoråå kiertåmållå saadaan tanko 23 siirtymåån (kuvio 1).In order to adjust the length of the dosing stroke, the adjusting rod 23 is made longitudinally displaceable with respect to the handle. At the top of the rod 23 35 there is thus a bearing wheel 25, the axis of which extends across the longitudinal groove of the rod. The rod 23 is furthermore mounted eccentrically on the wheel 25. Thus, by rotating the wheel, the rod 23 is displaced (Fig. 1).

44

Kuvioissa on esitetty vain yksikanavainen pipetti, mutta luonnollisesti keksinto soveltuu sellaisenaan myos monikana-vapipetteihin.Only a single-channel pipette is shown in the figures, but of course the invention as such is also applicable to multi-channel shake pipettes.

Claims

91043

A step pipette with a body, a cylinder (4) and a movable mSntS (13) between the down and up positions of the cylinder, a mSnnS dosing rod (5) with a dosing toothing (7) attached to the body in the body. an up and down position movable striker (8) corresponding to the dosing toothing (7) for moving the dosing rod (5) and the mSnnS (3) with mSS-long strokes down to 10 pressures, in the dosing rod (5) with a longitudinal transmission tooth (14), a toothed rack (16), and a camshaft (13) parallel to the dosing rod (5) in the body and also a longitudinal gearing (15) which is in a row with the gearing (16) but on the opposite side from the dosing of the dosing rod (5). ), an impact spring (12) associated with the impactor (8) for pressing the impactor presses the dispensing toothing (7), characterized in that the impactor spring (12) is associated with its release member (18) to release the tension of the impactor spring (12) to the last full after a spore attack.

Pipette according to Claim 1, characterized in that the striker is provided with a release spring (19) for releasing the striker (8) from the metering tooth (7) after the last stroke 25.

Pipette according to Claim 2, characterized in that the release spring (19) also acts as a return spring for the striker (8) in order to return it to its up position after the impact.

Pipette according to Claim 2 or 3, characterized in that the force of the release spring (19) is less than the force of the striker (8) in the dosing tooth (7) during the stroke without the striker spring (12).

Pipette according to one of Claims 1 to 4, characterized in that the release member is a release member (18) which moves with the filling rod (13).

Pipette according to claim 5, characterized in that the impact spring (12) has a free pSS (17) resting on the actuating rod (13) and in that the releasing member is an insertion (18) in the actuating rod, such as a notch, notch, hole or rod pSS. the free end of the spring (12) settles after the last full-length stroke so that the tension of the shock spring (12) is released.

Pipette according to Claim 6, characterized in that the striker is a striker (8) mounted on a lever (9) movable between the lower and upper positions at the top and that the striker spring is an upward V-shaped striker spring (12).

Pipette according to Claim 7, characterized in that the release spring is an upwardly pulling release spring 10 (19) attached to the striker (8) from its bearing point on the filling rod (13).

Pipette according to one of Claims 1 to 8, characterized in that the metering tooth (7) is provided with an adjusting rod (23) on its side and movable in its direction, with a cam (24) at its lower end which disengages the striker (8) in the exit step. dosing teeth (7). 91043