JPS60117Y2 - Automatic stop device for density gradient liquid preparation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic stop device for a density gradient liquid preparation device that creates a density gradient liquid used, for example, in zonal centrifugation or density gradient centrifugation.

Conventionally, such a density gradient liquid production device has been disclosed in Japanese Patent Application No. 45-13559 (Japanese Patent Publication No. 5O-11) filed earlier by the present applicant.
No. 081), Jitsugan No. 48-92234 (Jikko 53)
-10356), etc., and as an automatic stop device for such a density gradient creation device, there is Utility Application No. 1983-97583, which was previously filed by the present applicant.

This Japanese Utility Model Application No. 53-97583 discloses that in a supply pipe that supplies a conductive gradient liquid from a preparation device to equipment using gradient liquid such as a zonal rotor or tube, at least By applying a minute voltage to the two electrodes and detecting electrical connection and disconnection between the electrodes, the presence of bubbles and the end of operation are detected, and the production device is automatically operated by the detection power. It is something that makes it stop.

The automatic stop device for such a density gradient liquid production device has the following problems.

In other words, it was not possible to determine whether it was due to the generation of bubbles and the completion of the gradient liquid preparation work, or whether the gradient liquid was not fully heated before operation.

Therefore, when starting the density gradient liquid preparation device, it was necessary to turn off the automatic stop device using a manual switch.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to
The automatic stop device is not operated, and the operation is automatically stopped only when the generation of bubbles during operation and the completion of gradient liquid preparation work are detected.

Therefore, in the present invention, at least three pipes are provided at predetermined intervals along the piping path for supplying conductive gradient liquid from the production device to the zonal rotor and tube gradient liquid using equipment. By applying a minute voltage to the electrodes and detecting electrical connections and interruptions between the electrodes,
It is characterized in that it detects whether it is at the time of startup, the generation of bubbles during operation, or the end of operation, and the operation of the production apparatus is automatically stopped based on this detection output.

Note that during startup, even if air bubbles are detected, the operation will not be stopped.

FIG. 1 is a diagram showing an embodiment of the present invention.

A dense liquid contained in a container 1 is pumped by a triple peristaltic pump 5 driven by a motor 6 into a container 2 containing a less dense liquid, which is made of magnetic material and driven by a motor 4. The mixture is mixed by a stirring element 3.

The mixed liquid in the container 2 is sent at twice the flow rate by two of the three pumps 5 through the supply piping 7 to a device using a gradient liquid (not shown).

Therefore, the density of the gradient liquid sent from container 2 is initially low;
After that, it increases linearly.

The bubble detection sensor group 8 constituting a part of the bubble detection device 9 provided in the supply pipe 7 includes at least three electrodes 81 . That is, it is composed of an electrode 81A on the front side in the liquid feeding direction, an intermediate electrode 81C1, and an electrode 81B on the terminal side, and a voltage is constantly applied to the electrode 81C.

Therefore, depending on the connection/cutoff state between the electrodes 81A-8IC and between the electrodes 81B-81C, it is detected whether it is starting, normal operation, or the completion of bubble generation and creation, and the operation of the pump 5 is continued based on the detection result. Or it can be stopped automatically.

The correspondence between them is shown below.

At startup, there is no gradient liquid in the supply pipe 7, and the electrode 81
Both A-81C and 81B-81C are off, transistors 91 and 92 are both off, relay coil 94 is not energized, and normally open contact 93 remains open.

Therefore, the pump 5 can be driven.

During normal operation, a gradient liquid exists in the supply pipe 7, and the electrode 8
1A-81C and 81B-81C are both on, transistor 91 is on, transistor 92 is off, relay coil 94 is not energized, and normally open contact 93 remains open. Yes, the pump 5 continues to operate.

When the gradient liquid production operation is completed or when bubbles are generated in the supply piping, the bubbles pass through the bubble detection sensor 8.

During this process, the electrodes 81B-81C are on, and the electrodes 81B-81C are on.
1A-81C, an off state occurs, transistor 91 is off, transistor 92 is on, relay coil 94 is energized, and normally open contact 93 is closed.

As a result, the relay 11 is energized and its contact 12 is actuated to stop the pump 5 and activate the buzzer 13.

Since the relay 11 constitutes a holding circuit, the pump 5 can be restarted by pressing the switch 14.

As described above, according to the present invention, the stopping device of the aircraft does not work at the time of starting, but the stopping device works when air bubbles are generated during normal operation and at the end of operation. There is no need to turn off the automatic stop device with a manual switch, and the generation of bubbles and the completion of production can be reliably detected, so vapor lock etc. can be prevented.

[Brief explanation of drawings]

Fig. 1 is an electric circuit diagram showing one embodiment of the device of the present invention;
The figure is a sectional view showing one embodiment of a bubble detection sensor. In the figure, 7 is a supply pipe, 8 is a group of bubble detection sensors, 8
1A, 81B, and 8 IC are electrodes, and 11 is a relay.

Claims (1)

[Scope of utility model registration request] In an automatic stop device in a density gradient liquid preparation device, the stop device is actuated to stop the operation of the machine based on the detection output of a bubble detection device that detects air bubbles in the liquid feeding path of the created density gradient liquid. The detection device has at least three air bubble detection sensors arranged sequentially at intervals in the liquid feeding direction, and when only the sensor on the front side in the liquid feeding direction detects air bubbles, the detection output causes the sensor to stop the air bubbles. An automatic stop device in a density gradient liquid production device, characterized in that the device is configured to operate the device.