LIQUID DISPENSER

Abstract: Liquid dispenser, which comprises at least two tubing pumps (1, 2), which have been fitted side by side so that their rotors (3, 4) are mounted on the same shaft of rotation. Between each rotor (3, 4) and the shaft (5) of rotation there is a freewheel or freewheels (6 to 9), by means of which each rotor (3, 4) can be rotated by means of the shaft (5) of rotation in one direction of rotation only, i.e. either clockwise or anticlockwise. The freewheel or freewheels (8, 9) of at least one rotor (4) have been mounted in a direction opposite to the freewheel or freewheels (6, 7) of one or several other rotors (3), so that the direction of rotation of the said at least one rotor (4) is opposite to the direction of rotation of the said one or several other rotors (3).

Description: Liquid dispenser -J» Tubing pumps, for which the designation of '* tubing pump or peristaltic pump is used in the English 5 language, are in extensive use in transfer or dosage of liquids. A tubing pump is an essential part, e.g., in continuous-flow analyzers. In the pumps in use the tubes used for the measurement of liquids pass on a tube base, and a rotor rests against this base. A 10 second alternative is that the tubes pass as partly tensioned around the rotor. Usually, on the outer cir¬ cumference of the rotors, there are rolls mounted on shafts as freely revolving and placed at slight distan¬ ces from each other. The said rolls roll along the 15 outer face of the tube and at the same time cause a flow of the liquid in the tube in the direction of the rotor. In the tubing pumps commonly available, the tube bases related to the rotors comprise one or several tubes. The rotor of such tubing pumps may be rotated 20 clockwise or anticlockwise, and in this way the liquid in the tube can be made to move forwards or backwards. A major drawback of the tubing pumps described above is that by their means it is not possible, at the same time, to remove liquid from a vessel and immediately 25 to transfer another liquid into the vessel. ' Likewise, by means of the devices described above, it is not possible to add a desired quantity of a liquid into a vessel and immediately to remove a desired quantity of liquid out of the vessel. 30 It is an object of the present invention to eliminate the above drawback, and the liquid dispenser in accordance with the invention is mainly characterized in that at least two tubing pumps have been fitted side by side so that their rotors are mounted on the same 35 shaft of rotation and that between each rotor and the shaft of rotation there is a freewheel or freewheels, by means of which each rotor can be rotated by means of the shaft of rotation in one direction of rotation only, i.e. either clockwise or anticlockwise, and that the freewheel or freewheels of at least one rotor have been mounted in a direction opposite to the freewheel or freewheels of one or several other rotors, so that the direction of rotation of the said at least one rotor is opposite to the direction of rotation of the said one or several other rotors. In one exemplifying embodiment of the inven- tion, on a joint shaft rotated by one motor there are, by the intermediate of freewheels, two rotors connected to their respective tube bases.. By means of the joint shaft rotated by the motor, out of the two rotors placed side by side, one can be rotated anticlockwise and the other one clock¬ wise by means of the freewheel or freewheels fitted between the shaft and the rotor so that, when one rotor revolves, the other rotor is stationary. The respective tube base of each rotor may comprise several tubes, whereat, by means of an appropriate intermediate piece, liquid can be removed simultaneously from the vessels by means of one rotor/tube-base combination and, forthwith or after a certain time, liquid can be added by means of the other rotor/tube-base combination simultaneously into the same vessels. These steps of "addition and removal can be repeated in the desired way or in accordance with a certain program as many times as is required in each particular case. The operation described above is an essential one, e.g., in many immunological assays (e.g. EIA, FIA, RIA) when a certain reaction mixture is removed from the reaction vessels and it is substituted by washing solution, which must often be replaced several times by fresh washing solution, e.g., to intensify the washing of the reaction vessel. The invention comes out in more detail from the following description and from the attached drawings, wherein Figure 1 shows an exemplifying embodiment of the invention as a side view and Figure 2 is a sectional view at A-A of the device shown in Fig. 1. In Fig. 1, a joint piece 12 connects the shaft 11 of the motor 10 to the shaft 5, which passes through the frame 13 beam 14 and is mounted to corres¬ ponding bearings 17 and 18 in the beams 15 and 16. In Fig. 1, the rotors 3 and 4 are mounted to the joint shaft 5 by means of freewheels 6, 7, 8 and 9. When the shaft 5 revolves, e.g., clockwise, the rotor 3, coupled by the freewheels 6 and 7, revolves along with the shaft 5 and, at the same time, the freewheels 8 and 9 disconnect the rotor 4 from the shaft 5, whereat the rotor 4 is stationary. When the shaft 5 revolves anti¬ clockwise, the rotor 4 revolves along with the shaft 5 as coupled by its freewheels 8 and 9 , and the rotor 3 is stationary, having been disconnected by its freewheels 6 and 7 from the movement, of rotation of the shaft 5. As is shown in Figures 1 and 2, the rolls 22 mounted on shafts 21 at the end flanges .19.and 2Q of the rotor 3 of the tubing pump 1 , the number of which rolls 22 can be at least three, mangle the tubes 24 connected to the tube base 23 so that the- mangling of the tubes 24 produces a liquid flow in each tube 24 in the way that usually takes place in tubing pumps. The construction and operation of the tubing pump 2 is equivalent. The exemplifying embodiment described above may operate as an independent apparatus, but it may also constitute of part of a larger unit, e.g. of an analyzer. Moreover, on the joint shaft 5 there may be more than two rotors 3 and 4 one after the other, connected by freewheels 6 to 9 to the movement of the shaft 5 in the desired way, e.g. as controlled by a certain program.

Claims: WHAT IS CLAIMED IS: Liquid dispenser, c h a r a c t e r i z e d in that at least two tubing pumps (1, 2) have been fitted side by side so that their rotors (3, 4) are mounted on the same shaft (5) of rotation and that between each rotor (3, 4) and the shaft (5) of rotation there is a freewheel or freewheels (6 to 9) , b " y means of which each rotor (3, 4) can be rotated by means of the shaft (5) of rotation in one direction of rotation only, i.e. either clockwise or anticlockwise, and that the freewheel or freewheels (8, 9) of at least one rotor (4) have been mounted in a direction opposite to the free¬ wheel or freewheels (6, 7) of one or several other rotors (3) , so that the direction of rotation of the said at least one rotor (4) is opposite to the direction of rotation of the said one or several other rotors (3) .

Inventors: EKHOLM PERTTI, EKHOLM, PERTTI
Applicants: LABSYSTEMS OY
Application year: 1983
Main classification: F04B43
IPC codes: F04B43