JPH0460450A - Detecting apparatus of remaining liquid - Google Patents

Abstract

PURPOSE:To facilitate detection of remaining liquid in a very small quantity and to improve the precision in detection by comparing outputs of two photoelectric conver sion sensors and by outputting a signal when a difference between the two outputs exceeds a prescribed value. CONSTITUTION:The bottom 11 of a bottle 1 is irradiated from below and a light passing through the bottom 11 of the bottle and a remaining liquid 2 is sensed by two photoelectric sensors 61 and 62 provided above the mouth of the bottle. The sensor 61 senses a transmitted light including ones in both visible and infrared areas, while the sensor 62 senses a transmitted light only in the infrared area through an optical filter 7. Next, a difference between electric outputs obtained by photoelectric conversion by the sensors 61 and 62 is measured and thereby the presence of the remaining liquid 2 is detected. When the remaining liquid 2 is absent, in other words, lights in virtually the same quantity reach the sensors 61 and 62 and a difference in the quantity of light between them is small. When the remaining liquid 2 is present, only the quantity of the light reaching the sensor 62 diminishes and the difference between the electric outputs obtained by the photoelectric conversion by the two sensors becomes large. By measuring the difference between the electric output of the sensors 61 and 62accord ingly, the presence of the remaining liquid 2 can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a residual liquid detection device for detecting liquid such as cleaning liquid remaining at the bottom of a transparent bottle such as a glass jar.

[Conventional technology]

BACKGROUND ART Drinking water, beer, etc. are sold in glass containers, but before filling the glass containers (bottles) with liquid, there is a step of cleaning the containers. In particular, regarding recycled bottles such as beer bottles that are collected and reused after being used by consumers, there are many cases where garbage and waste are mixed into the bottles. Cleaning is required. In this case, the bottle is cleaned with cleaning liquid and clean water,
In the subsequent draining process, the water may not be drained completely and water mixed with cleaning liquid may remain in the bottle. Of course, since the bottle is intended for human consumption, it is undesirable for residual liquid to remain in the bottle before filling.

The conventional method for detecting residual liquid in bottles is as follows:
There are methods that detect residual liquid by examining the degree of absorption by the liquid of high frequency waves, ultrasonic waves, or infrared light, or methods that detect residual liquid by bringing an electrode close to the liquid and detecting changes in capacitance. There was a way. Currently, detection methods that utilize infrared light are often used.

However, when there is a large amount of residual liquid, it is easy to detect the residual liquid using any method, but it is very difficult to detect the presence of a very small amount of liquid, and it is difficult to stably detect a small amount of residual liquid. It is hoped that a device capable of this will be put to practical use.

[Problem to be solved by the invention]

Although it is possible to detect a certain amount of residual liquid using the conventional method described above, the problem lies in detecting a trace amount of residual liquid. One of the reasons why detection is difficult is that the smaller the amount of residual liquid, the less the degree of light absorption. Second, the containers filled with liquid (often glass bottles) also absorb a certain amount of light when it passes through, so differences in the thickness of each container and the intensity of the colored color can be detected by the photoelectric sensor. This is because it often causes a change in the amount of light received.

In order to detect a small amount of residual liquid, it is necessary to amplify and expand the small amount of change in the photoelectric conversion voltage energy of the photoelectric (conversion) sensor. This amplification of the amount of change also amplifies the change in the amount of light received due to the change in the amount of light transmitted through the container as described above, and due to this effect, it is difficult to detect only the change in the amount of light received by the photoelectric sensor due to the true residual liquid. is difficult. Therefore,
There is a limit to the detection of a trace amount of residual liquid, and the current situation is that it is sufficient to detect a certain amount of residual liquid.

Therefore, in view of the above-mentioned problems, the present invention aims to provide a residual liquid detection device that solves the problems.

[Means to solve the problem]

According to the present invention, there is provided a light source [3) that irradiates the bottom (11) of the transparent bottle (1) with light including visible light and infrared light, and a light source [3] that irradiates the bottom (11) of the transparent bottle (1) with light from the light source that passes through the bottom of the bottle. The two photoelectric conversion sensors (6,) and (62) to be attended, and an optical filter that allows only infrared light to pass through, which is placed on the light receiving surface of one of these two photoelectric conversion sensors (6□) [7 ) and means (9), (10) for comparing the outputs of these two photoelectric conversion sensors and outputting a signal when the difference between the two outputs exceeds a predetermined value.
As a result, a residual liquid detection device for detecting whether liquid remains at the bottom of a transparent bottle is obtained.

[Effect]

According to the present invention, light including both the visible and infrared regions is irradiated from below to the part of the bottle (1) where residual liquid is thought to exist, for example, the bottom (1), and Two photoelectric (conversion) sensors (6,), (62) provided above the mouth receive the light that has passed through the bottle bottom and the liquid (2) remaining on the bottle bottom. One photoelectric sensor (6I) receives transmitted light including both visible and infrared regions as it is, and the other photoelectric sensor (6□) has an optical filter (7 ) to receive transmitted light only in the infrared region.

The presence of residual liquid (2) is detected by measuring the difference between the electrical outputs photoelectrically converted by these two photoelectric sensors. In other words, when there is no residual liquid, almost the same amount of light reaches both optical sensors, so there is little difference in the amount of light received between them, but when there is residual liquid, Only the amount of light reaching the photoelectric sensor (6°) decreases, and the difference in the electrical output of photoelectric conversion between both optical sensors increases. This is because in the infrared light region, transmitted light is significantly attenuated by the aqueous solution, whereas in the visible light region, no significant change occurs. Therefore, by measuring the difference in the electrical outputs of both optical sensors, the presence of residual liquid can be detected.

Furthermore, in the present invention, the change in the amount of attenuation of transmitted light due to the container is
Since there is less change in visible light and infrared light than in an aqueous solution, this affects the amount of light received by both optical sensors in the same way, cancels out, and appears as a change in the difference in the electrical output of both optical sensors. Therefore, only the attenuation of transmitted light due to the residual liquid can be stably detected as a change in the electrical output of the photoelectric sensor (62).

Embodiment] FIG. 1 is a partially sectional route map of an embodiment of the present invention. In the figure, (1) is, for example, a glass bottle, and residual liquid (2) is present at the bottom (1,). (3) is a glass bottle from below the bottle (1,). A light source that irradiates light including visible light and infrared light, and (4) is a light source that irradiates light including visible light and infrared light to the bottle bottom (II) and the light source in order to evenly irradiate the bottle bottom (1,) with the light from light source (3). (3) is the light diffusing plate placed between the bottle bottom (5)
11) is a condensing lens placed above item 4 that condenses the light that has passed through the condenser lens, and its tip axis is aligned with the central axis of the bottle (1), and is indicated by (OA). (6,), (62) are two photoelectric (conversion) sensors arranged above the condenser lens (5) across the optical axis (OA), and (7) is one photoelectric sensor (6,
Infrared (optical) filters (8,) and (82) are provided on the light-receiving surface of the photoelectric sensors (6,) and (6,), which allow only light in the infrared region to pass through. Two amplifiers each amplify the amplification, (9) is a zero adjuster such as a potentiometer that adjusts the potential difference between the two amplifiers (8,) and (8□) to zero, and (10) is its intermediate tap. (9,) is a power amplifier for generating a detection output signal as described below.

Since the photoelectric sensors (6□) and (6,) are provided close to each other, the light transmitted through the bottle bottom (1,) is focused by the condensing lens (5). The optical image of □) occupies approximately the same area in both optical sensors (6,) and (62) (described later with reference to FIG. 2). Photoelectric sensor (6,).

The electrical output of (62) is transmitted through amplifiers (8,) and (8, respectively).
□) and supplied to the zero regulator (9). If a positive phase amplifier is used as the amplifier (8,) and a negative phase amplifier is used as the amplifier (82), and the outputs of both are supplied to the zero regulator (9), the zero regulator (9) (potentiometer) The potentials at both ends are in reverse phase with each other, so at this time, the bottom of the bottle (
When there is no residual liquid (2) on 1,), both optical sensors (6
, ), (62), etc., to make the potential of the middle tap (91) of the potentiometer (9) zero. If the illumination light is received in the absence of residual liquid (2), and a slight potential difference appears at the middle tap (91) of the potentiometer (9), the potentiometer (9)
The potential of the intermediate tap (91) may be set to zero by adjusting the voltage.

The light source (3) uses one that emits light in both the visible and infrared regions, but the photoelectric sensor (6) receives the transmitted light that has passed through the bottom of the bottle and the residual liquid (2) present at the bottom of the bottle. do. On the other hand, since the light receiving surface of the photoelectric sensor (62) is provided with an infrared filter (7) that allows only light in the infrared region to pass through, the photoelectric sensor (62) receives transmitted light only in the infrared region.

Generally, in the case of infrared light with a long wavelength of 1 to 2 microns or more, the transmission attenuation rate due to an aqueous solution becomes extremely large, so if there is residual liquid (2), The photoelectric conversion output of the photoelectric sensor (62) that receives light only in the outer region is significantly smaller than the output of the photoelectric sensor (61). An appropriate infrared filter (7) having a cutoff frequency within the above range may be used.

The photoelectric sensor (61) also receives light in the visible light range, but since light in the visible light range has a small amount of attenuation even when passing through an aqueous solution, the photoelectric sensor (61)
6I) does not cause a large change in the amount of light received.

From the above, depending on the presence or absence of residual liquid (2), the electrical output of the amplifier (8,) connected to the photoelectric sensor (61) and the electrical output of the amplifier (82) connected to the photoelectric sensor (62) can be determined. It makes a big difference. Therefore, if there is no residual liquid (2), the zero regulator (9) connected to the amplifiers (8,) and (82) should be adjusted so that no potential difference occurs at the output terminal (91). , a potential difference appears at the output end of the zero regulator (9) only when there is residual liquid C].

The output of the zero regulator (9) is supplied to a power amplifier (10). This power amplifier (10) emits an electrical output indicating that the presence of residual liquid (2) has been detected if the potential from the zero regulator (9) exceeds a preset constant value. Please note that this power amplifier (1
Although not shown, the electric output of step 0) may be used to activate a light or sound warning means, or a bottle removal device may be activated to detect the presence of residual liquid (2) and remove the bottle. You may do so.

FIG. 2 is an enlarged plan view showing the light receiving areas of the photoelectric sensors (61) and (6□). In the same figure, (
11) is the inner diameter area of the bottle bottom (II), (12,) and (
122) are photoelectric sensors (6I) and (62), respectively.
) shows the light receiving area for the inner diameter area (11). The two photoelectric sensors (6,) and (62) are installed close to each other, but each is slightly offset from the optical axis (OA) of the condenser lens (5), so the light is not received as shown in the figure. A slight shift will occur in the areas (12,) and (12,). However, even if there is such a slight shift in the light receiving area, this does not pose any practical problem for the purpose of detecting the residual liquid (2). Even if the structure is such that each part of the bottle bottom (11) receives light, it is clear that the object of the present invention can be achieved by the principle of operation of the present invention as explained in the previous section. Probably.

FIG. 3 shows another embodiment of the invention. In this example, the above-mentioned deviation does not occur in the light receiving areas of both light receiving sensors (6,) and (6□). That is, as shown in the same figure (, condensing lens (
On the optical axis (OA) of 5), a 71-humira (13) is provided between the condenser lens (5) and the photoelectric sensors (6,), (62), and one photoelectric sensor, for example (6,), is provided. receives the light that has passed through the half mirror (13) along the optical axis (OA), and the other photoelectric sensor (62) receives the light that has passed through the half mirror (13) along the optical axis (OA).
3) so as to receive the refracted light. By doing this, the photoelectric sensor (6,), (62)
It is possible to match the light receiving areas of the two. Others are 3rd r.
The example of g:i is exactly the same as the example of FIG.

FIGS. 4 and 5 are route maps showing the main parts of still another embodiment of the present invention. As shown in Figure 4A, which shows the side cross section of the bottom of the bottle (11), there is a bottle bottom (11) of the bottle (1).
Some have a convex central part. in this case,
When the amount of residual liquid (2) is small, this residual liquid (2) is distributed in a donut shape around the outer circumference of the bottle bottom (11), and is not present in the central protrusion.

The fourth embodiment of the present invention for efficiently detecting residual liquid (2) in such a bottle is shown in the fourth projection view of the bottle bottom (1,).
This will be explained with reference to FIG. B and FIG. 5 showing the main parts of the embodiment. That is, as shown in Figure 4, one photoelectric sensor (
61) is the central protrusion (14,) of the bottle bottom (1,)
The other photoelectric sensor (
The photoelectric sensor (62) receives only the light that passes through the donut-shaped part (14□) along the vicinity of the outer periphery of the bottle bottom (1,).By doing this, the photoelectric sensor (62) Since the presence or absence of liquid greatly affects the degree of attenuation of transmitted light, the presence of a trace amount of residual liquid (2) can be detected efficiently.

That is, as shown in FIG. 5, an optical mask (151) is provided on the light receiving surface of the photoelectric sensor (6,), and an optical mask (15□) is provided on the light receiving surface of the photoelectric sensor (62). Optical mask (15,
), as shown in the plan view of arrow (A) in the same figure, for example, there is a circular transparent part (15A) in the center and an opaque part 1 around it.
(15B) Consists of. The other optical mask (152
), as shown in the plan view of arrow (B) in the same figure, includes a circular opaque part (15C) at the center, a donut-shaped transparent part (150) around it, and an opaque part (15E) at the outer periphery.
).

Therefore, the respective optical masks (15,) and (15□
) is the light receiving area (14,) as described in Figure 4B above.
, (14,). In addition, photoelectric sensor (6,)
It goes without saying that even if the optical mask (15,) is omitted and the light transmitted through the entire bottle bottom (11) is received, there is no problem with the operation of the present invention as described above. Furthermore, the fifth
Although not shown in the figure, other configurations and operations are explained in the third section.
This is exactly the same as the example in the figure.

Figure 6 shows a special configuration of photoelectric sensors (6,), (6,) that allows transmission of the bottle bottom (11) at one point on the optical axis (OA>) without using a half mirror (13). It is a route map of another embodiment of the present invention that can receive light and achieve the object of the present invention.That is, the shape of the photoelectric sensor (61) is a small disk shape, and the shape of the photoelectric sensor (62) is in the same figure. As shown in the projection diagram, it has a donut shape, and both are arranged concentrically and on the same plane with respect to the optical axis (OA).Thereby, the photoelectric sensor (6,) is located only in the central part of the bottom of the bottle. The photoelectric sensor (6□) receives the transmitted light only from the donut-shaped part around the outer periphery of the bottle bottom (11), and has the same effect as the example shown in Fig. 5. Of course, it is necessary to provide an infrared filter (7), which is also donut-shaped, on the light-receiving surface of the donut-shaped photoelectric sensor (6□).

In the various embodiments described above, the bottle bottom (II) is all illuminated from below and the transmitted light passing through the bottle bottom (1, ) is received from above the opening. In order to implement this, there is no need to stick to this, and various other configurations can be considered.

FIGS. 7A and 7B are a side view and a plan view, partially in section, showing essential parts of one such embodiment.

As shown in the figure, photoelectric sensors (6,) and (6□) are arranged on the side surface near the bottom (11) of the bottle. In this case, the illumination light source (3) is divided into two beam-shaped projection type illumination light sources (31) and (3□) and placed outside the bottle bottom (11), and each light source (3,) is placed outside the bottle bottom (11). , (3□) are provided on the outer sides of the photoelectric sensors (6,) and (62) opposite to each other with respect to the diameter of the bottle bottom (11). Light source (3,), (3,
) are placed so that the beam light from them will reach the residual liquid (
2), and effectively remove residual liquid (2).
Set a position where it is easy to detect. The other configurations, operations, and effects are the same as those of the previous embodiments, so illustrations and explanations will be omitted.

Furthermore, although these embodiments have been explained using a simple photoelectric sensor, it is possible to logically perform the main functions and operations of the present invention in the same way by using a video camera, a CPU, etc. would be easy for a person skilled in the art.

〔Effect of the invention〕

According to the present invention, it is now easier to detect trace amounts of residual liquid, which has been difficult until now.Moreover, factors that hinder stable improvement of detection accuracy due to the influence of changes in uneven thickness and color of containers (glass bottles, etc.) can be excluded.

Furthermore, since the structure of the present invention is extremely simple, its embodiments are extremely easy. Further, as explained in the embodiments, various implementation methods can be adopted in accordance with the gist of the present invention, so the scope of application is wide and practical implementation is easy.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 is a route map for explaining its operation, Fig. 3 is a block diagram of a second embodiment of the invention, and Fig. 4 A and B are A route map for explaining the third embodiment of the present invention, FIG. 5 is a route map of the main part of the third embodiment of the present invention, FIG. 6 is a block diagram of the fourth embodiment of the present invention, FIGS. 7A and 7B are route maps of the main parts of the fifth embodiment of the present invention. In the figure, (1) is the bottle, (2) is the residual liquid, (3) is the light source, (4) is the light diffuser, (5) is the condenser lens, (6,),
(6□) is a photoelectric conversion sensor, (7) is an infrared filter, (
8,), (82) is an amplifier, (9) is a zero adjuster,
(10) is a power amplifier, (101). (1, 12) indicate optical masks, respectively. Deputy Director Hide Hitomatsu Kuma Morimoto g Mei's Atsushi z0 Kasumi-gakure's connection line J Figure 3 / 1g Mei υ proverb 3 example case diagram Figure 5 mouth ~ 31 This invention Me Atsushi 5 trrfl Jn Abbreviation Takeshi Figure 7

Claims (1)

[Claims] 1. A light source that irradiates the bottom of a transparent bottle with light including visible light and infrared light, and two photoelectric conversion units that receive light from the light source that passes through the bottom of the bottle. A sensor, an optical filter that allows only infrared light to pass, which is placed on the light receiving surface of one of the two photoelectric conversion sensors, and the outputs of the two photoelectric conversion sensors are compared and the difference between the two outputs is a predetermined value. 1. A residual liquid detection device for detecting whether liquid remains at the bottom of a transparent bottle, comprising means for outputting a signal when the amount exceeds the limit. 2. A light source placed below the bottom of the bottle that irradiates the bottom of the transparent bottle with light including visible light and infrared light, and a light diffuser plate placed between the light source and the bottom of the bottle. two photoelectric conversion sensors placed above the bottle opening of the bottle that receive light from the light source transmitted through the bottom; and a condenser lens placed between the two photoelectric conversion sensors and the bottle opening. and an optical filter that transmits only infrared light, which is placed on the light receiving surface of one of the two photoelectric conversion sensors, and the outputs of the two photoelectric conversion sensors are compared and the difference between the two outputs exceeds a predetermined value. 1. A residual liquid detection device for detecting whether or not liquid remains at the bottom of a transparent bottle, characterized by comprising means for outputting a signal when a liquid is present at the bottom of a transparent bottle. 3. A light source placed below the bottom of the transparent bottle that irradiates the bottom of the bottle with light including visible light and infrared light, and a light diffusion plate placed between the light source and the bottom of the bottle; two photoelectric conversion sensors arranged above the mouth of the bottle that receive light from the light source that has passed through the bottom of the bottle; and a light condensing sensor arranged between the two photoelectric sensors and the mouth of the bottle. a lens; an optical filter disposed on the light receiving surface of one of the two photoelectric conversion sensors that allows only infrared light to pass; and a half mirror disposed between the condenser lens and the two photoelectric conversion sensors; , means for comparing the outputs of the two photoelectric conversion sensors and outputting a signal when the difference between the two outputs exceeds a predetermined value, the optical axis of the condensing lens being aligned with the central axis of the bottle. match,
The photoelectric conversion sensor without an optical filter is arranged along the optical axis so as to receive the light that has passed through the half mirror, and the other photoelectric conversion sensor is arranged so as to receive the light reflected by the half mirror. A residual liquid detection device that detects whether liquid remains at the bottom of a transparent bottle. 4. A light source placed below the bottom of the transparent bottle that irradiates the bottom of the bottle with light including visible light and infrared light, and a light diffusion plate placed between the light source and the bottom of the bottle; two photoelectric conversion sensors placed above the mouth of the bottle that receive light from the light source that has passed through the bottom of the bottle; and an infrared ray placed on the light receiving surface of one of the two photoelectric conversion sensors. It has an optical filter that allows only light to pass through, and means that compares the outputs of the two photoelectric conversion sensors and outputs a signal when the difference between the two outputs exceeds a predetermined value, and the optical axis of the condensing lens is is aligned with the central axis of the bottle, and the above 2
A residual liquid detection device for detecting whether liquid remains at the bottom of a transparent bottle, characterized in that a plurality of photoelectric conversion sensors are arranged concentrically and on the same plane as the optical axis.