JPH0119103B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dispensing device for quantitatively dispensing reagents and the like in automatic chemical analyzers and the like.

Conventionally, in this type of device, the following problems have occurred when setting the discharge amount from the pump.

(1) It was expensive because a pulse motor was used as the drive source for the pump.

(2) The stroke was set manually by inserting and removing a stroke adjustment plate inserted into the pump's drive section.

(3) When a pulse motor is not used, it is difficult to automate the setting of the discharge amount, and even if it were automated, the mechanism would be complicated and expensive.

(4) The discharge amount could not be set steplessly.

(5) It had many mechanical elements and could not be made compact.

(6) The discharge motor was stopped each time the flow path switching valve was operating.

The present invention was made in order to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a high-precision dispensing device that can continuously set the discharge amount from a pump and has a quick response. It is said that

That is, the feature of the present invention is that a flow path switching valve is provided on the discharge port side of a pump that performs suction and discharge operations when a plunger is operated by a motor, so that liquid can be sucked and discharged to a plurality of locations. The dispensing device is characterized in that an elastic tube is inserted between the discharge port side of the pump and the flow path switching valve.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is an operation panel for performing various operations such as setting the reagent discharge amount, 2 is a central processing unit (hereinafter referred to as "CPU") that controls the operation of the entire system, and 3 is an operation panel 1. and CPU
It has an interface function between
A control circuit that controls each part according to the control operation output of the CPU 2; 4 a pulse counter that counts input pulses and provides the count value to the CPU 2; 5 a motor that is driven and controlled by the control circuit 3; Rotationally driven lead screw, 7
8 is a syringe as a pump whose plunger 7a is driven by a motor 5 via a lead screw 6; 8 is a highly elastic elastic tube connected to the suction and discharge port of the syringe 7; 9 is an elastic tube 8; A connected electromagnetic valve for switching a flow path, 10 a reagent container containing a reagent, 11 a tube forming a flow path between the electromagnetic valve 9 and the reagent container 10;
2, 12a, 12b, . . . are reaction tubes containing sample liquids to be injected with reagents, 13 is a conveyor chain for supporting and transporting the reaction tube 12, 14 is a motor for operating the conveyor chain 13, 15
16 is a tube that forms a flow path for injecting reagents from the electromagnetic valve 9 to the reaction tube 12 at a predetermined position on the conveyor chain 13; It is a sensor.

Next, the operation in such a configuration will be explained.

First, the amount of reagent discharged into each of the ten reaction tubes 12 is set to 50 μm using the operation panel 1, for example.
A valve drive signal is output from the control circuit 3. The electromagnetic valve 9 connects the flow path between the reagent container 10 and the syringe 7. Next, the CPU 2 drives the motor 5 via the control circuit 3 to rotate the lead screw 6 and lower the plunger 7a (direction D in the figure).
The reagent is sucked up in the direction A shown in the diagram, into the tube 11,
It enters the syringe 7 through the elastic tube 8. The rotation sensor 16 detects the amount of reagent in the syringe 7 depending on the number of rotations of the lead screw 6.
For example, the pulse counter 4 is notified by a rotation pulse signal that 1500μ has been input. Pulse counter 4 outputs pulses to syringe 7 based on the count value of the number of pulses.
Inform CPU2 that 1500μ has been inserted. The CPU 2 gives commands to the control circuit 3 to stop the rotation of the motor 5 and to switch the electromagnetic valve 9. (Now the solenoid valve 9 connects the syringe 7 and tube 15.)
Next, the motor 5 is rotated to raise the plunger 7a (in the U direction in the figure), and the reagent is sent out from the syringe 7.
The reagent is again discharged into the tube 15 in the direction B in the figure through the elastic tube 8 and the electromagnetic valve 9.
Based on the signal from the rotation sensor 16, the CPU 2 changes the flow path of the electromagnetic valve 9 to the direction C shown in the figure when the amount of reagent discharged into the reaction tube 12a reaches 50μ, and returns 100μ of the reagent in the syringe 7 to the reagent container 10. .
Since the elastic tube 8 momentarily swells during the operation time of the electromagnetic valve 9, the motor 5 can switch only the electromagnetic valve 9 while continuously rotating.
Next, the reaction tube 12b is moved below the outlet of the tube 15, and 50μ of the reagent is added thereto. Thereafter, in the same manner, only the electromagnetic valve 9 is operated, the flow path is switched to the B and C directions, and the reagent is dispensed into the ten reaction tubes 12. After the reagent is discharged into the tenth reaction tube 12j, all remaining reagents are returned to the reagent container 10 through the flow path in the C direction.

In this way, reagents can be dispensed into the ten reaction tubes 12a to 12j without stopping the motor 5. That is, the motor 5 continuously rotates, the plunger 7a continuously rises, and the reagent in the syringe 7 is continuously discharged into the elastic tube 8. At this time, when the electromagnetic valve 9 is switched, the flow path is closed. is cut off, and the discharged reagent has nowhere to go. In this case, the bulge of the elastic tube 8 allows the above-mentioned stranded reagent to be taken over, and therefore, the discharge operation and flow path switching operation can be performed independently without overloading the plunger 7a. You will be able to do this continuously.

In the above, the discharged reagent determined by the amount of movement (stroke amount) of the plunger 7a is distributed to each reaction tube 12 according to the time that the flow path is open by the electromagnetic valve 9. The discharge amount is A [/sec], and the time during which the flow path is open for each reaction tube 12 is t [sec].
If so, At[] can be dispensed into each reaction tube 12, respectively.

In this case, what defines the dispensed amount is the stroke amount of the plunger 7a, and if the rotation of the motor 5 is doubled, in the above example, the discharge amount will be
2A[/sec], 2At for each reaction tube 12
[ ] can be dispensed. In other words, the switching control of the time when the flow path is open performed by the electromagnetic valve 9 is as follows.
This merely controls the distribution of the ejected reagents. This differs between when the elastic tube 8 is "inflated" and when it is "non-inflated".
This is because it is taken into consideration that the amount of reagent flowing out from the electromagnetic valve 9 will be completely different.

By doing as described above, the following effects can be obtained.

(1) The amount of reagent discharged can be automatically set by the CPU according to the measurement item.

(2) (1) allows easy and quick switching of measurement items.

(3) Due to (1), it is possible to respond to emergency reagent discharge with fewer steps.

(4) According to (1), the reagent discharge amount is not set manually, so there is no error in setting the reagent discharge amount.

(5) Due to (4), expensive reagents are not wasted.

(6) It can be constructed at low cost because there are few mechanical components.

(7) The pump's discharge operation does not stop every time the valve is switched, so it is quiet with little mechanical shock.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without changing the gist thereof.

That is, the present invention operates the switching valve without stopping the pump drive motor by inserting an elastic tube between the pump and the switching valve. It can also be implemented with a dynamic pump.

FIG. 2 shows an embodiment in which the present invention is applied to a crank mechanism driven pump.

In FIG. 2, 50 is a motor, 60 is a crank mechanism driven by the motor 50, 61 is a slide member that is driven forward and backward by the crank mechanism 60, 62 is a guide that regulates the sliding direction of the slide member 61, and 71 to 74 are first to fourth syringes (functioning as pumps) whose plungers 71a to 74a are driven simultaneously by the slide member 61, and 81 and 84 are suction and discharge ports of the first to fourth syringes 71 to 74, respectively. Elastic tubes 91 to 94 connected to the outlets are switching valves 10 connected to the elastic tubes 81 to 84;
1 to 104 are first to fourth reagent containers, 111 to 1
14 are reagent containers 101 to 104 and a switching valve 91
- Tube provided between 94, 121-1
24 is the reaction vessel of the first to fourth channels; 15
1 to 154 are switching valves 91 to 94 and reaction vessel 1
This is a tube provided between 21 and 124. In this case, different amounts of reagents can be dispensed into the reaction vessels 121-124 of each channel by one movement of the slide member 61 simply by controlling the switching of the switching valves 91-94 independently.

Moreover, it can be used not only as a reagent pump but also as a sampling pump of an automatic chemical analyzer or the like.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the system configuration of one embodiment of the present invention, and FIG. 2 is a diagram showing the main part configuration of another embodiment of the invention. DESCRIPTION OF SYMBOLS 1...Operation panel, 2...Central processing unit, 3...Control circuit, 4...Pulse counter, 5, 14, 50...Motor, 6...Lead screw, 7, 71, 74...
Syringe, 8, 81-84... Elastic tube,
9,91-94...Switching valve, 10,101-1
04...Reagent container, 11, 15, 111-114,
151-154...Tube, 12, 12a, 12
b..., 121-124... reaction tube, 13... conveyor chain.

Claims (1)

[Claims] 1. In a dispensing device in which a flow path switching valve is provided on the discharge port side of a pump that is suctioned and discharged by operating a plunger by a motor, and liquid is sucked and discharged to multiple locations,
A dispensing device characterized in that an elastic tube is inserted between the discharge port side of the pump and the flow path switching valve.