JPH03150418A - Method and apparatus for measuring liquid level - Google Patents

Abstract

PURPOSE:To prevent the generation of the error by waving, etc., by suspending the measurement of a liquid level for a specified period of time after the start of liquid replenishment. CONSTITUTION:A valve 4 is opened to feed high-pressure fluid 5 to a pressure vessel 3 when the liquid level of a coating liquid 1 in a storage part 10 detected by a liquid level sensor 30 attains a prescribed value or below. The coating liquid 1 is then replenished into the storage part 10 through a filter 20 and a supply pipe 22. Since the waving arises on the liquid level near the supply pipe 22, the liquid level is measured by the liquid level sensor 30 and decision is made whether the prescribed level is attained or not upon lapse of the prescribed time after the start of the replenishment.

Description

[Detailed description of the invention] Purpose of the invention.

(Industrial Application Field) This invention controls the level of liquid stored in a storage part to a constant level, applies the liquid to a continuously running plate-like body, and reduces the amount of liquid consumed during the application. In case of replenishment,
The present invention relates to a method and device for measuring a liquid level, which avoids the effects of ripples and the like due to replenishment and accurately measures and controls the liquid level.

(Prior Art) As a method or apparatus for applying a coating liquid to a plate-like body such as a web, there are methods and apparatuses disclosed in Japanese Patent Publication No. 58-4589 and Japanese Patent Application Laid-Open No. 62-7467 by the present applicant.

In these devices, a coating liquid stored in a reservoir is applied to a plate-shaped body (web) via an application roller.

(Problems to be Solved by the Invention) In the conventional apparatus described above, there is no method for accurately controlling the level of the coating liquid applied to the plate-shaped body, and the coating layer on the plate-shaped body may vary depending on the liquid surface level of the coating liquid. There were variations in the thickness of the raw material.

This invention was made due to the above-mentioned circumstances,
An object of the present invention is to provide a liquid level measuring method and device that can always coat a plate-like object with a uniform coating layer by accurately controlling the liquid level of the coating liquid. be.

Structure of the Invention (Means for Solving the Problems) The present invention relates to a liquid level measuring method and device. When maintaining a predetermined level and performing a predetermined operation by replenishing the liquid, this is achieved by performing the measurement after a predetermined time has elapsed after the replenishment. Furthermore, a liquid level sensor that measures the liquid level of the liquid in the reservoir, a supply pipe that replenishes the liquid according to the measurement result by the liquid level sensor, and a liquid level sensor that is disposed in the reservoir between the liquid level sensor and the supply pipe. It consists of a breakwater bulkhead and
This is achieved by making it possible to perform the measurement without being affected by the replenishment.In the liquid level measuring method of the present invention, the liquid is replenished into the reservoir from the supply pipe, and the liquid level is measured by the liquid level sensor. and measure
When the liquid level is lower than a predetermined level, liquid is replenished from the supply pipe. When replenishing liquid from the supply pipe, disturbances such as ripples occur on the liquid surface near the supply pipe, so do not use the liquid level sensor to measure the liquid level while the ripples are occurring, or close the supply pipe and liquid level sensor. A wave-proof bulkhead is provided between the water and the water to reduce the size of the ripples, and the required control is performed by accurately measuring the liquid level.

(Example) FIG. 1 shows an example of a device for realizing this invention.
The coating liquid 1 is contained in a bottle 2, and the bottle 2 is contained in a pressure vessel 3. High-pressure fluid 5 is supplied to the pressure vessel 3 via a valve 4, and the application liquid 1 in the bottle 2 is discharged through the supply pipe by the supply of the pressure fluid 5 to the filter 20.
After the foam removal pipe 21 removes the foam, the valve 23 is opened so that the clean coating liquid 1 filtered through the filter 20'C is supplied or replenished into the reservoir 10 through the supply pipe 22. It has become. The coating liquid 1 is stored in the storage part 1o, and the coating liquid 1 is applied to the plate-like body through the coating means 11, and the liquid level of the coating liquid 1 is measured by the liquid level sensor 30. It has become.

The operation of this configuration will be explained with reference to the flowchart of FIG.

The liquid level sensor 30 measures the liquid level of the coating liquid 1 stored in the reservoir lO (Step S1), and determines whether the liquid level of the coating liquid 1 is at a predetermined level or not (Step S).
2) If the predetermined level is reached, close the valve 4 to stop the supply of the coating liquid 1 through the pressure vessel 3 and the filter 20 (Step S3), and in this state, the plate-like material is coated by the coating means II. (Step 54). When the plate-like object is coated by the coating means +1, the level of the coating liquid 1 gradually decreases, and gradually falls below a predetermined level as measured by the liquid level sensor 30 (
As a result, the valve 4 is opened to supply the high-pressure fluid 5 to the pressure vessel 3 to replenish the coating liquid 1 (step 551). In this case, the coating liquid 1 is supplied to the filter 20 and the supply pipe 22. The liquid is then replenished into the reservoir 10, or ripples occur on the liquid surface near the supply pipe 22.
In this invention, the liquid level sensor 3
The liquid level is measured at step S6), and it is determined from the measurement result whether the liquid level has reached a predetermined level.

Therefore, the liquid level sensor 30 can avoid the influence of ripples on the liquid surface due to replenishment of the coating liquid 1 supplied from the supply pipe 22, and can accurately measure the level of the liquid level.

In the above embodiment, the liquid level is measured by the liquid level sensor after the influence of ripples due to replenishment has disappeared.
As shown in Figure 3 (8) and (B), 4j4 supply pipe 2
2 and the liquid level sensor 3o in the reservoir 1o.
2 may be arranged so that ripples caused by replenishment of the coating liquid 1 from the supply pipe 22 do not affect the vicinity of the liquid level sensor 3o. In other words, since the wave-proof bulkhead 12 is provided so as to cross the liquid surface near the supply pipe 220, even if the liquid surface is rippled due to replenishment from the supply pipe 22, the barrier wall protruding from the liquid surface will not be affected. Since its propagation is blocked by the wave partition wall 12, the measurement by the liquid level sensor 30 is hardly affected.

Furthermore, FIG. 4 shows another method of the present invention, in which the distance between the supply pipe 22 and the liquid level sensor 30 is widened, and even if ripples occur due to replenishment of the coating liquid 1 in the supply pipe 22, the liquid level sensor 30
It shows a method of measuring in such a way that the influence of the ripples does not appear in the vicinity of .

In addition, although the coating liquid is taken as an example in the above description, it is similarly applicable to other liquids.

Effects of the Invention: As described above, according to the measuring method of the present invention, the liquid level is measured by the liquid level sensor while avoiding or reducing the effect of ripples caused by replenishing the coating liquid. Accurate liquid level measurement becomes possible.

Fig. 1 is a diagram showing an example of the configuration of a coating liquid supply device to which the present invention can be applied, Fig. 2 is a flowchart showing the method of the invention, and Figs. FIG. 4 is a side view and a front view of an exemplary apparatus, and FIG. 4 is a configuration diagram showing still another embodiment of the present invention.

1... Coating liquid, 2... Bottle, 3... Pressure vessel, 4
...Valve, 5...High pressure fluid, 1o...Reservoir,
11... Application means, 20... Filter, 30...
Liquid level sensor.

Client agent Cheap shape male

Claims (1)

[Claims] 1. When the level of the liquid in the reservoir is measured and the liquid is replenished according to the measurement result to maintain it at a predetermined level and perform a predetermined operation, after a predetermined period of time has elapsed after the replenishment, A liquid level measuring method characterized in that the above measurement is performed. 2. A liquid level sensor that measures the liquid level of the liquid in the reservoir, a supply pipe that replenishes the liquid according to the measurement result by the liquid level sensor, and a supply pipe that is disposed in the reservoir between the liquid level sensor and the supply pipe. 1. A liquid level measuring device comprising a breakwater bulkhead provided therein so that the measurement can be carried out without being affected by the replenishment.