JPS598766B2 - Liquid height detection device for liquid in container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for easily and accurately detecting the presence or absence of liquid, excess or deficiency, or liquid level in a liquid-filled container such as an apple, a vial, or a bottle being transported.

Conventionally, various means for detecting the presence or absence of liquid filled in a container and the liquid level have been devised.

In particular, in containers containing liquid medicines, foods, chemicals, cosmetics, etc., such as apples, vials, and bottles being transported, detecting the filling amount requires a device to detect the liquid level in the container itself. It belongs to a technical field that is difficult for various reasons, such as the lack of equipment and the speeding up of the product production process. However, regarding such detection means, there are some known improvements to the conventional method of checking the liquid level with the naked eye. For example, X-rays are projected from the side of the container, and the transmitted X-rays are absorbed by the presence or absence of liquid. A means for detecting the difference in the amount of light or visible light is projected from the side of the container, and the transmitted light is detected by detecting the difference in light amount due to the presence or absence of liquid or the difference due to the refraction of light that occurs in the liquid or at the meniscus. There are ways to do so. 10 However, the means using X-rays requires the use of safety equipment and is complicated to handle, thus lacking in convenience.

In addition, although there are clear differences in principle between the above methods that use visible light, in practice they make judgments with very subtle differences15, and they are sensitive to various types of scattered light and diffusely reflected light. Due to its presence, the measurement results were not reproducible and the accuracy was unsatisfactory. That is, when the transmitted light or the refracted light passes through the inner wall of the container, a portion of the transmitted light is reflected by the inner wall and is scattered, or the inner wall of the container becomes wet. In some cases, the transmitted light is not transmitted in principle and becomes scattered light, so even if a highly sensitive detector is used, it is not possible to measure a difference that is significant enough to be practical. 25 In addition, each of the above means has light emitters and receivers facing each other on both sides of the container, and when using a screw conveyor or star foil, which is commonly used as a container transport device, apples, vials, etc. There is also a drawback that it is not possible to install light emitters and receivers on both sides of the container, such as when the container is 30 times smaller than the conveyor or star foil, or the liquid level is low.

Although various methods have been considered, there is no practically preferred detection method, especially as production processes become faster and more streamlined.The advent of a simple and highly accurate container liquid level detection method was requested.

As a result of intensive research to find a detection device that can accurately determine the liquid filling state of a container that is progressing at high speed under such technical standards, the present inventor has developed the detection device of the present invention by focusing on diffusely reflected light from the liquid surface. A device was discovered and completed.

That is, the present invention provides electromagnetic waves installed directly below the bottom of a container being transported, in order to easily and accurately detect the presence or absence of liquid in the container, such as an ampoule, vial, or bottle, or the liquid level. The projector, the upper and lower moving partition plate that moves up and down parallel to the container to adjust the allowable range of the amount of liquid filled in the container, and the moving partition plate cause diffuse reflection on the liquid surface in the container. It is characterized by being comprised of a single electromagnetic wave receiver capable of receiving only electromagnetic waves in a substantially horizontal direction among electromagnetic waves, and configured to judge whether or not the liquid filling amount is good or bad depending on the reception level. The object of the present invention is to provide a device for detecting the level of liquid in a container being transported.

The feature is that it projects electromagnetic waves from the bottom of the container, receives the electromagnetic waves diffusely reflected on the liquid surface in the container, and among the diffusely reflected electromagnetic waves, only the electromagnetic waves reflected in the permissible direction reach the receiver. The point is to limit the direction of reception. The present invention can be carried out using not only street light but also various electromagnetic waves such as ultrasonic waves, infrared rays, ultraviolet rays, X-rays, and γ-rays.

However, other electromagnetic waves are preferable to gamma rays and X-rays in order to avoid safety equipment and complexity of handling. Therefore, the method of the present invention is not limited to transparent or translucent containers or liquids, and has the advantage that it can be applied to detecting the liquid level of opaque containers or liquids. The present invention shields unnecessary diffusely reflected electromagnetic waves from the electromagnetic waves diffusely reflected on the liquid surface through a slit, and directly detects whether or not the necessary electromagnetic waves are received. It is also extremely advantageous industrially that the liquid level can be detected with high precision without the need for a sensitive electromagnetic wave detector. Furthermore, the present invention can be applied to screw conveyors and star foils that can be conveyed at high speed, and the measurement results are stable and can be detected with high accuracy.

According to the inventor's experiments, the present invention made it possible to determine the predetermined liquid height in the container with a high accuracy of ±0.5 mm or more. Hereinafter, the present invention will be explained in more detail with reference to the drawings. Figures 1 to 3 show a book using a container (in this case shown as an ampoule) that passes continuously at a rate of 5 or more bottles per second. FIG. 1 is a schematic diagram showing the invention.

FIG. 1 is a schematic diagram in which the present invention is applied to an ampoule filled with a normal amount of a drug solution. In the drawings, numeral 1 indicates a container mounting platform of a container conveying device such as a screw conveyor or star foil. Of course, as long as it is stable against vibrations to the extent that it does not interfere with measurement, it is not limited to screw conveyors or star foils, but it can be linked to allow the container to pass quickly through the location where the detector is installed while leaving it still. It may also be a belt conveyor type stand. Reference numeral 2 denotes a hole bored in the base 1, which is provided to project electromagnetic waves vertically upward from the bottom of the container, and has an appropriate size.

Therefore, it is maximized to the extent that it does not interfere with the continuous passage of the container. 3 is an ampoule, and 4 is an electromagnetic wave projector.

The electromagnetic wave projector 4 may be any device commonly used for projection. Reference numeral 5 indicates the liquid level of the liquid in the container, 6 indicates the progress of waves diffusely reflected in the horizontal direction on the liquid level 5, and 7 indicates an electromagnetic wave receiver.

The electromagnetic wave receiver 7 may be a simple, commonly used device that can simply receive electromagnetic waves and transmit the pulses to the defective product elimination mechanism. 8 is an electromagnetic wave diffusely reflected by the liquid surface 5. An ampoule 3 for passing a part of the ampoule and completely shielding a part of the ampoule 3 is moved stably at a high speed of 5 or more per second on the table 1 in accordance with the operation of a screw conveyor or star foil.

As shown in the drawing, it is moving stably at high speed. As shown in the drawing, when the ampoule 3 passes directly above the hole 2 made in the base 1, the bottom of the ampoule 3 has a hole 2 located vertically at the bottom, with the center of the ampoule 3 being approximately in the middle. Yes, it passes through the center of the hole 2 and the center of the bottom of the ampoule 3.
Seed ÷ Z =: [Me F travels vertically upward and is diffusely reflected in all directions by the liquid surface 5 in the ampoule 3.

A vertically movable partition plate 8 is installed on the side opposite to the screw conveyor or star foil side of the ampoule 3 at an appropriate distance from the ampoule 3, and which forms an appropriate gap 9 according to the required accuracy of judgment. It is set up opposite. The vertically movable partition plate 8 can be adjusted up and down, and if the gap 9 formed by the partition plate is determined by adjustment, the vertically movable partition plate 8 is integrated with the electromagnetic wave receiver 7. That's fine. Among the electromagnetic waves diffusely reflected by the liquid surface 5, the diffusely reflected electromagnetic waves in the horizontal direction pass through the gap 9 between the upper and lower movement partition plates 8 configured according to the required accuracy when the liquid is filled in a normal amount. . The electromagnetic wave receiver 7 is located adjacent to or integrated with the vertical movement partition plate 8 so that it can receive signals from the entire gap 9 with the central axis of the gap 9 as its center point. Therefore, the electromagnetic waves that have passed through the gap 9 are received by the electromagnetic wave receiver 7 and converted into an instruction pulse indicating that the standard amount of chemical solution is being filled. However, as shown in Figure 2, the chemical solution is filled in excess of the normal amount, or the third
As shown in the figure, when the chemical solution is insufficient, the electromagnetic waves diffusely reflected by the drug surface 5 are transmitted to the ampoule 3 and the upper and lower movement partition plates 8.
, the width of the gap 9, and the depth of the vertical movement partition plate 8, the wave is completely blocked and is not received by the electromagnetic wave receiver 7.

Although not shown in the diagram, electromagnetic waves are naturally not received when there is no liquid. Therefore, such ampoules are determined to be defective and automatically rejected. This exclusion mechanism is carried out by methods and equipment commonly used in the art. Therefore, according to the present invention, by appropriately adjusting the distance between the ampoule 3 and the vertically movable partition plate 8, the width of the gap 9, and the depth of the vertically movable partition plate 8, or by adjusting the distance between the ampoule 3 and the vertically movable partition plate 8. And if the depth of the partition plate 8 is fixed,
By simply adjusting the gap 9 above and below the partition plate 8, the liquid level can be easily detected with any precision.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the device of the present invention in a state where the container is filled with a chemical solution at a predetermined liquid level, Fig. 2 is a schematic diagram showing an overfilling state, and Fig. 3 is a schematic diagram in a shortage state. . Explanation of symbols, 1...Container mounting stand, 2...
Small hole, 3... ampoule, 4... electromagnetic wave projector, 5... liquid level, 6... reflected wave,
7... Receiver, 8... Partition plate, 9 gap.

Claims (1)

[Claims] 1. An electromagnetic wave projector 4 provided directly below the bottom of the container 3 being transported, and a vertically movable device that can be moved up and down parallel to the container 3 to adjust the permissible range of the amount of liquid filled in the container 3. A single electromagnetic wave receiver 7 that can receive only substantially horizontal electromagnetic waves among the electromagnetic waves diffusely reflected on the liquid surface 5 in the container 3 by the partition plate 8 and the vertically movable partition plate 8.
1. A liquid level detection device for a liquid in a container being transported, characterized in that the device is configured to determine whether the amount of liquid filled is good or bad depending on whether or not the liquid is received.