阅读说明：本技术 液体洗涤剂检测装置及使用其的洗衣机 (Liquid detergent detection device and washing machine using same ) 是由 中林邦博 安藤胜 前川隆纪 池上教久 于 2020-03-10 设计创作，主要内容包括：本发明提供能够高精度地检测流动于透明管的透明度高的液体洗涤剂的有无的液体洗涤剂检测装置及使用其的洗衣机。液体洗涤剂检测装置,包括发光元件及受光元件。在透明管内有液体洗涤剂的情况下,照射至透明管的扩散光受到折射而被聚光,受光元件接收已被聚光的光。在透明管内没有液体洗涤剂的情况下,照射至透明管的扩散光在透过透明管内后也持续扩散,受光元件接收透过了透明管的光的一部分。液体洗涤剂检测装置的控制部在受光元件的输出较第一阈值高的情况下,检测到透明管内有液体洗涤剂,在受光元件的输出较第一阈值低的情况下,检测到透明管内没有液体洗涤剂。(The invention provides a liquid detergent detection device capable of detecting the existence of a liquid detergent with high transparency flowing in a transparent tube with high precision and a washing machine using the same. The liquid detergent detection device includes a light emitting element and a light receiving element. When the liquid detergent is present in the transparent tube, the diffused light applied to the transparent tube is refracted and condensed, and the light-receiving element receives the condensed light. When the liquid detergent is not present in the transparent tube, the diffused light applied to the transparent tube is diffused continuously even after passing through the transparent tube, and the light receiving element receives a part of the light having passed through the transparent tube. The control unit of the liquid detergent detection device detects that the liquid detergent is present in the transparent tube when the output of the light-receiving element is higher than the first threshold value, and detects that the liquid detergent is not present in the transparent tube when the output of the light-receiving element is lower than the first threshold value.)

1. A liquid detergent detection device that is used with a transparent tube attached thereto and that detects the presence or absence of a liquid detergent in the transparent tube, comprising:

a light emitting element and a light receiving element which are disposed opposite to each other with the transparent tube interposed therebetween;

a tube holding unit for holding the transparent tube at a proper position with respect to the liquid detergent detection device; and

a control unit that detects the presence or absence of the liquid detergent in the transparent tube based on the amount of light received by the light receiving element;

the light emitting element irradiates diffused light to the transparent tube;

the light emitting element and the light receiving element have the following configurations:

(1) when a liquid detergent is present in the transparent tube, the diffused light applied to the transparent tube is refracted by the liquid detergent in the transparent tube and condensed, and the light receiving element receives the condensed light,

(2) when the liquid detergent is not present in the transparent tube, the diffused light applied to the transparent tube is continuously diffused even after the light passes through the transparent tube, and the light-receiving element receives a part of the light that has passed through the transparent tube; and is

The control unit detects that the liquid detergent is present in the transparent tube when the output of the light-receiving element is higher than a first threshold value, and detects that the liquid detergent is not present in the transparent tube when the output of the light-receiving element is lower than the first threshold value.

2. The liquid detergent detecting device according to claim 1,

detecting an end of the bubble using a second threshold value smaller than the first threshold value when the bubble is mixed in the liquid detergent flowing in the transparent pipe;

the control unit detects an end of the bubble when the output of the light receiving element is lower than a second threshold value.

3. The liquid detergent detecting device according to claim 2,

the control unit detects a region where no bubbles are present, a region where bubbles are present, and a region where an end of bubbles is present, when bubbles are mixed in the liquid detergent flowing through the transparent tube, and calculates a mixing ratio of bubbles from a ratio of the regions.

4. A washing machine which receives a supply of liquid detergent from an external liquid detergent container via a transparent pipe, characterized in that,

the liquid detergent detection device of any one of claims 1 to 3 including the transparent tube mounted thereto.

5. A washing machine according to claim 4,

the transparent tube has a substantially inverted U-shaped arrangement portion formed by a first standing portion and a second standing portion extending in the vertical direction and a bending portion connecting the first standing portion and the second standing portion at the upper portion;

the liquid detergent detection device is installed at a position closer to a downstream side in a flowing direction of the liquid detergent than the bent portion.

6. A washing machine according to claim 4 or claim 5,

after the liquid detergent detection device detects that the liquid detergent in the transparent pipe is used up, the error is removed according to the detergent use-up error removal operation performed by a user;

the post-error-relief action includes an initial filling action of filling the transparent tube with a liquid detergent.

7. A washing machine according to claim 6,

when the liquid detergent detecting means does not detect the presence of the liquid detergent in the transparent tube within a predetermined time-out period after the initial filling operation is started, the initial filling operation is terminated and the end of the liquid detergent in the transparent tube is detected again.

8. A washing machine according to claim 6 or 7,

the initial filling operation is finished after the liquid detergent detection device detects that the liquid detergent is in the transparent tube and the pump connected to the transparent tube is operated for a specified time;

the post-error-relief operation includes a washing tank cleaning operation performed after the initial filling operation.

Technical Field

The present invention relates to a liquid detergent detection device for detecting the presence or absence of a liquid detergent flowing in a pipe in a washing machine having a structure in which a liquid detergent is supplied from a liquid detergent container by liquid feeding using the pipe (tube), and a washing machine using the same. The present application claims priority from patent application 2019-48363, filed in japan on 3, 15, 2019, the contents of which are incorporated herein by reference.

Background

In recent years, washing machines often include an automatic detergent supply function. For example, in a washing machine for business use, a large liquid detergent container is connected to the washing machine via a pipe, and liquid is supplied from the liquid detergent container using the pipe to supply a liquid detergent.

In the liquid feeding using such a tube, detection of the liquid detergent in the tube is indispensable for detecting the presence or absence of the liquid detergent in the liquid detergent container and controlling the amount of the liquid detergent to be fed accurately. Patent document 1 discloses a fluid detection device for liquid detergents, detergents (shampooes) and the like using a Photo interrupter (Photo interrupter). In the fluid detection device disclosed in patent document 1, a light emitted from a light emitting element of a photointerrupter is transmitted through a transparent tube, and the amount of the transmitted light is detected by a light receiving element, thereby detecting the presence or absence of a fluid (liquid detergent, detergent) in the transparent tube. Specifically, when a fluid is present in the transparent tube, the amount of transmitted light decreases due to the light being blocked by the fluid, and therefore, the presence or absence of the fluid in the transparent tube can be detected by comparing the output of the light receiving element with a threshold value.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 8-292082.

Disclosure of Invention

Problems to be solved by the invention

In the fluid detection device described in patent document 1, the low transparency of the fluid flowing through the transparent tube is a condition for performing highly accurate detection. However, when the fluid detection device is applied to a washing machine, there is a problem that it is difficult to detect the liquid detergent with high accuracy because the liquid detergent often has high transparency. This is because, in the liquid detergent having high transparency, the difference in the amount of transmitted light due to the presence or absence of the detergent in the transparent tube is small. Further, an optical sensor device such as a photointerrupter is likely to change in output level due to a change in temperature or deterioration with age, and if the difference in the amount of transmitted light is small due to the presence or absence of a detergent, there is a risk of causing erroneous detection depending on the usage conditions.

The present invention has been made in view of the above problems, and an object thereof is to: provided are a liquid detergent detection device capable of detecting the presence or absence of a highly transparent liquid detergent flowing through a transparent tube with high accuracy, and a washing machine using the same.

Means for solving the problems

In order to solve the above-described problems, a liquid detergent detection device according to a first aspect of the present invention is a liquid detergent detection device that is used by attaching a transparent tube and detects the presence or absence of a liquid detergent in the transparent tube, the liquid detergent detection device including: a light emitting element and a light receiving element which are disposed opposite to each other with the transparent tube interposed therebetween; a tube holding part for holding the transparent tube at a proper position relative to the liquid detergent detection device; and a control unit for detecting the presence or absence of the liquid detergent in the transparent tube based on the amount of light received by the light receiving element; the light emitting element irradiates diffused light to the transparent tube; the light emitting element and the light receiving element have the following configurations: (1) when the liquid detergent is in the transparent tube, the diffused light irradiated to the transparent tube is refracted by the liquid detergent in the transparent tube to be condensed, and the light receiving element receives the condensed light; (2) when the liquid detergent is not present in the transparent tube, the diffused light irradiated to the transparent tube is continuously diffused after passing through the transparent tube, and the light receiving element receives a part of the light passing through the transparent tube; the control unit detects that the liquid detergent is present in the transparent tube when the output of the light receiving element is higher than a first threshold value, and detects that the liquid detergent is not present in the transparent tube when the output of the light receiving element is lower than the first threshold value.

According to the above configuration, the liquid detergent detection device can change the output of the light receiving element by using the presence or absence of the light condensing action in the case where the liquid detergent is present or absent in the transparent tube. Therefore, when the liquid detergent flowing through the transparent tube is a highly transparent substance, the output difference of the light receiving element can be obtained more, and the presence or absence of the highly transparent liquid detergent can be detected with high accuracy regardless of the use condition of the liquid detergent detection device.

In addition, the liquid detergent detection device may be configured to: detecting an end of the bubble using a second threshold value smaller than the first threshold value when the bubble is mixed in the liquid detergent flowing in the transparent tube; the control unit detects an end of the bubble when the output of the light receiving element is lower than a second threshold value.

According to the above configuration, when the bubble is present in the transparent tube, the bubble can be detected based on the end portion of the bubble, and the bubble can be detected with high accuracy. When the remaining amount of the liquid detergent container connected to the transparent tube is small, bubbles are generated in the transparent tube, and thus it is possible to detect that the remaining amount of the liquid detergent container is small.

In addition, the liquid detergent detection device may be configured to: the control unit detects a region where no bubbles exist, a region where bubbles exist, and a region where an end of bubbles exists, by distinguishing them, when bubbles are mixed in the liquid detergent flowing through the transparent tube, and calculates a mixing ratio of bubbles from a ratio of each of these regions.

According to the above configuration, the mixing ratio of the bubbles in the liquid detergent supplied through the transparent pipe is calculated, and the calculated mixing ratio of the bubbles can be used for controlling the supply amount of the liquid detergent to the washing machine.

In order to solve the above problem, a washing machine according to a second aspect of the present invention is a washing machine that receives a supply of a liquid detergent from an external liquid detergent container through a transparent pipe, the washing machine including: the liquid detergent detection device according to the above, which is attached to the transparent tube, is provided.

In the above washing machine, the transparent tube may be configured to: a substantially inverted U-shaped arrangement portion formed by a first standing portion and a second standing portion extending in the vertical direction and a bending portion connecting the first standing portion and the second standing portion at the upper portion; the liquid detergent detection device is installed closer to a downstream side of the flow direction of the liquid detergent than the bent portion.

According to the above configuration, the liquid detergent is caused to have a defoaming effect of separating the liquid detergent mixed with the bubbles into the liquid detergent and the air in the process of flowing from the bottom to the top in the first standing part and the process of flowing in the bent part. As a result, by installing the liquid detergent detection device on the downstream side of the bent portion, the liquid detergent mixed with the small bubbles can be prevented from flowing to the installation position of the liquid detergent detection device, and the liquid detergent detection device can appropriately and accurately detect the end of the liquid detergent. Alternatively, the detection accuracy of the mixing rate of the bubbles in the transparent tube can be improved.

In addition, the washing machine may be configured to: after the liquid detergent detection device detects that the liquid detergent in the transparent pipe is used up, the error releasing operation is carried out according to the detergent use-up error releasing operation carried out by a user so as to carry out the operation after the error is released; the post-error-relief operation includes an initial filling operation of filling the transparent tube with a liquid detergent.

According to the above configuration, after the liquid detergent in the transparent pipe is detected to be used up, the liquid detergent container is replenished with the liquid detergent, and then the initial filling operation is performed, whereby the transparent pipe can be filled with the liquid detergent. Thus, the liquid detergent detection device can be prevented from detecting the liquid detergent is used up again before the liquid detergent reaches the liquid detergent detection device at the next use of the washing machine.

In addition, the washing machine may be configured to: when the liquid detergent detecting device does not detect the presence of the liquid detergent in the transparent tube within a predetermined timeout period after the initial filling operation is started, the initial filling operation is terminated and the end of the liquid detergent in the transparent tube is detected again.

According to the above configuration, when the administrator of the washing machine or the like performs the error release operation after the liquid detergent container is not replenished with the liquid detergent, it is possible to avoid the situation where only the pump continues to operate in a state where the transparent pipe is not filled with the liquid detergent.

In addition, the washing machine may be configured such that: the initial filling operation is finished after the liquid detergent detection device detects that the liquid detergent is in the transparent tube and the pump connected with the transparent tube is operated for a set time; the post-error-relief operation includes a washing tank cleaning operation performed after the initial filling operation.

According to the above configuration, the liquid detergent detection device can operate the pump for a predetermined time even after detecting the presence of the liquid detergent in the transparent tube, thereby completely filling the liquid detergent to the distal end of the transparent tube. In this case, since some liquid detergent is put into the washing tub of the washing machine at the end of the initial filling operation, it is conceivable that the washing tub cleaning operation is performed after the initial filling operation.

ADVANTAGEOUS EFFECTS OF INVENTION

In the liquid detergent detection device and the washing machine according to one aspect of the present invention, the output of the light receiving element is changed by the presence or absence of the light condensing action in the case where the liquid detergent is present or absent in the transparent tube. Thus, when the liquid detergent flowing through the transparent tube is a highly transparent substance, the output difference of the light receiving element can be obtained more, and the presence or absence of the highly transparent liquid detergent can be detected with high accuracy regardless of the use condition of the liquid detergent detection device.

Brief description of the drawings

Fig. 1 is a front view showing an external appearance of a washing system according to a suitable example of the present invention.

Fig. 2 is a perspective view of the inside of the accessory mounted on the upper surface of the washing machine as viewed from the rear surface side.

Fig. 3(a) is an explanatory view showing a detection principle in the case where the liquid detergent is present in the transparent pipe, and (b) is an explanatory view showing a detection principle in the case where the liquid detergent is not present in the transparent pipe.

Fig. 4 is a diagram showing the state of the bubble in the transparent tube at the upper part, and a graph showing the relationship between the position of the bubble and the output (light receiving amount) of the light receiving element at the lower part.

FIG. 5 is an explanatory diagram showing a separation action of liquid detergent and air in the transparent pipe.

FIG. 6 is an explanatory diagram showing a structure in which a predetermined amount of liquid detergent is secured in a transparent tube.

Detailed Description

[ first embodiment ]

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the first embodiment, a liquid detergent detection apparatus capable of accurately detecting the presence or absence of a highly transparent liquid detergent flowing through a transparent tube will be described.

Fig. 1 is a front view showing a configuration of a washing system including a washing machine 100 as one example of application of the present invention. The washing system is composed of a washing machine 100, a liquid detergent container 200, and a transparent tube 20. The washing machine 100 is used as a service washing machine by mounting the accessory device 120 on the upper surface of the washing machine main body 110. In addition, the washing machine 100 receives a supply of liquid detergent from the liquid detergent container 200 via the transparent pipe 20. In fig. 1, one washing machine 100 is connected to one liquid detergent container 200 as an example, but a plurality of washing machines 100 may be connected to one liquid detergent container 200.

Fig. 2 is a perspective view of the inside of the attachment device 120 as viewed from the rear side. In fig. 2, a part of the external case is not shown in order to illustrate the inside of the accessory device 120. The liquid detergent detection device 10 attached together with the transparent tube 20 is disposed inside the accessory device 120. The accessory device 120 also includes a pump 30 for feeding the liquid detergent from the liquid detergent container 200 to the washing machine 100 through the transparent pipe 20, and a charging device 40 for charging a user using the washing machine 100.

As shown in FIG. 2, the liquid detergent detection device 10 has a tube installation groove 11 for installing a transparent tube 20 and a photointerrupter 12. The photointerrupter 12 is an example of the light emitting element and the light receiving element described in the claims. The liquid detergent detection device 10 also has a control unit (not shown) that determines the presence or absence of liquid detergent in the transparent tube 20 based on the output of the photointerrupter 12.

The transparent tube 20 is fitted into the tube fitting groove 11, and thus is fitted to the liquid detergent detection device 10. In the present embodiment, the transparent tube 20 is attached to the liquid detergent detection device 10 so as to extend in the vertical direction. The photointerrupter 12 is disposed so as to be detectable with respect to the transparent tube 20 in the middle of the tube installation groove 11. The photointerrupter 12 includes a light emitting element 12a (see fig. 3) and a light receiving element 12b (see fig. 3) disposed in opposition to each other with a transparent tube 20 interposed therebetween. Further, the photointerrupter 12 includes tube holding portions 12c at both ends in the extending direction (vertical direction in fig. 1) of the transparent tube 20. The light emitting element 12a and the light receiving element 12b are not limited to the configuration provided in the photointerrupter 12. For example, the liquid detergent detection device 10 may hold the light emitting element 12a and the light receiving element 12 b.

Next, the principle of detection of the liquid detergent detection device 10 in the case where the liquid detergent is present in the transparent tube 20 and the case where the liquid detergent is absent will be described with reference to fig. 3(a) and (b).

FIG. 3(a) shows the detection principle when the liquid detergent is present in the transparent tube 20. First, the light emitting element 12a irradiates diffused light to the transparent tube 20. When the liquid detergent is present, the light transmitted through the transparent tube 20 is refracted by the liquid detergent in the transparent tube 20, and is collected toward the light receiving element 12 b. As a result, the light receiving element 12b can receive most of the light transmitted through the transparent tube 20. The diffused light emitted from the light-receiving element 12b toward the transparent tube 20 is preferably entirely (or substantially entirely) emitted to the transparent tube 20. The transparent tube 20 has a cross section having a convex curved surface such as a circle or an ellipse in order to obtain a light condensing action.

Fig. 3(b) shows the detection principle of the case where there is no liquid detergent in the transparent tube 20. In the case where there is no liquid detergent, the light transmitted through the transparent tube 20 continues to be diffused without being condensed, and the light-receiving element 12b can receive only a part of the light transmitted through the transparent tube 20.

As described above, the liquid detergent detection apparatus 10 according to the first embodiment differs the amount of light received by the light receiving element 12b depending on the presence or absence of the light condensing action between the case where the liquid detergent is present in the transparent tube 20 and the case where the liquid detergent is absent. As a result, the controller included in the liquid detergent detection device 10 can compare the output of the light-receiving element 12b with a predetermined first threshold value, and determine that the liquid detergent is present in the transparent tube 20 when the output of the light-receiving element 12b is greater than the first threshold value and that the liquid detergent is not present in the transparent tube 20 when the output of the light-receiving element 12b is less than the first threshold value.

In the above detection principle of the liquid detergent detection device 10, when the liquid detergent is present in the transparent tube 20, it is necessary to sufficiently condense the light transmitted through the transparent tube 20 on the light receiving surface of the light receiving element 12 b. Therefore, in the photointerrupter 12, the transparent tube 20 must be disposed at an appropriate position with respect to the light emitting element 12a and the light receiving element 12 b. In the liquid detergent detection device 10, the tube holding portion 12c is provided in the photointerrupter 12, and the transparent tube 20 is held and fixed by the tube holding portion 12c, whereby such an appropriate arrangement can be obtained.

In the liquid detergent detection device 10, not only the arrangement positions of the light emitting element 12a and the light receiving element 12b but also the light receiving portion area of the light receiving element 12b are important elements. That is, the amount of light received by the light receiving element 12b when no liquid detergent is present in the transparent tube 20 differs depending on the area of the light receiving part of the light receiving element 12 b. Specifically, the smaller the light receiving portion area of the light receiving element 12b, the smaller the amount of light received by the light receiving element 12b in the case where there is no liquid detergent, and the larger the difference in output of the light receiving element 12b between the case where there is liquid detergent in the transparent tube 20 and the case where there is no liquid detergent. Therefore, the light receiving area of the light receiving element 12b may be set according to the level of the amount of light received by the light receiving element 12b when the liquid detergent is not present in the transparent tube 20.

The light receiving portion of the light receiving element 12b is preferably shaped like a slit whose longitudinal direction is the direction in which the transparent tube 20 extends (vertical direction in fig. 2). Since the transparent tube 20 has a cylindrical shape, a light converging effect is hardly obtained in the direction in which the transparent tube 20 extends, and the light converging effect shown in fig. 3 can be obtained in the direction along the cross section of the transparent tube 20. Therefore, by setting the shape of the light receiving portion of the light receiving element 12b to a narrow slit shape in the vertical direction in fig. 3, the output difference of the light receiving element 12b between the case where the liquid detergent is present in the transparent tube 20 and the case where the liquid detergent is absent can be obtained largely, and by setting the longitudinal direction of the slit to the extending direction of the transparent tube 20 (the front-rear direction of the paper surface in fig. 3), the irradiation light from the light emitting element 12a can be received more, and therefore the signal intensity of the light receiving element 12b can be increased.

In the first embodiment, the transparent tube 20 is premised on the liquid being sent from the liquid detergent container 200 to the washing machine 100, but if the remaining amount of the liquid detergent in the liquid detergent container 200 becomes small, air bubbles are mixed in the liquid detergent in the transparent tube 20. Such bubbles form a curved interface in the axial direction of the transparent tube 20 so as to divide the air and the liquid detergent.

The liquid detergent detection device 10 according to the first embodiment can also detect the interface of the bubble (bubble end region) in the transparent tube 20 by comparing the output (light receiving amount) of the light receiving element 12b with the second threshold value (< first threshold value). The detection principle thereof is explained with reference to fig. 4. The upper part of fig. 4 is a diagram showing the state of the bubbles in the transparent tube 20, and the lower part of fig. 4 is a graph showing the relationship between the positions of the bubbles and the output (light receiving amount) of the light receiving element 12 b. In fig. 4, a region in which the liquid detergent is present in the transparent tube 20 (no bubbles are present) is referred to as a region a, a region in which the liquid detergent is absent in the transparent tube 20 (bubbles are present, and the interface between air and the liquid detergent is absent) is referred to as a region B, and a region in which the bubble end portion is present in the transparent tube 20 (the interface between air and the liquid detergent is present) is referred to as a region C.

First, in the region a, as shown in fig. 3(a), the light transmitted through the transparent tube 20 is condensed, and the amount of received light becomes "large". In the region B, as shown in fig. 3(B), the light transmitted through the transparent tube 20 is diffused, and the amount of received light becomes "medium". Therefore, by setting the first threshold value between the light receiving amount in the area a and the light receiving amount in the area B, it can be determined that the liquid detergent is present in the transparent tube 20 when the output of the light receiving element 12B is larger than the first threshold value.

On the other hand, in the region C, since the irradiation light from the light emitting element 12a hits the end of the bubble, that is, the interface between the air and the liquid detergent and is reflected and scattered, the amount of light that is transmitted while being directed into the transparent tube 20 (light in the direction of the arrow from the top to the bottom in the region C in fig. 4) decreases. As a result, the amount of light received in the region C becomes "small". Therefore, by setting the second threshold value between the light receiving amount in the region B and the light receiving amount in the region C, it is possible to detect the bubble end portion in the transparent tube 20 when the output of the light receiving element 12B is smaller than the second threshold value. When the output of the light-receiving element 12b is smaller than the first threshold value and larger than the second threshold value, it can be determined that the liquid detergent is not present in the transparent tube 20.

As described above, the liquid detergent detection device 10 according to the first embodiment changes the output of the light receiving element 12b depending on whether or not the light condensing action is performed when the liquid detergent is present in the transparent tube 20 or when the liquid detergent is absent. Therefore, when the liquid detergent flowing through the transparent tube is a highly transparent substance, the output difference of the light receiving element 12b can be obtained largely, and the presence or absence of the highly transparent liquid detergent can be detected with high accuracy regardless of the use condition of the liquid detergent detection device 10.

In addition, even when a bubble is present in the transparent tube 20, the bubble can be detected by utilizing scattering of light at an end of the bubble. Thus, even when air bubbles are mixed in the liquid detergent conveyed through the transparent tube 20, it can be detected that the remaining amount of the liquid detergent container 200 is small. In addition, the mixing rate of the bubbles in the liquid detergent conveyed through the transparent pipe 20 is detected, and based on this, the supply amount of the liquid detergent to the washing machine 100 can be more accurately controlled.

[ second embodiment ]

In the second embodiment, a preferred use of the liquid detergent detection device 10 in the washing machine 100 will be described.

As shown in fig. 2, in the accessory device 120, the transparent tube 20 includes a substantially inverted U-shaped arrangement portion. The transparent tube 20 has a substantially inverted U-shaped arrangement portion formed by a first standing portion 21 and a second standing portion 22 extending in the vertical direction, and a bent portion 23 connecting the first standing portion 21 and the second standing portion 22 at the upper portion. The first standing part 21 and the second standing part 22 are such that the second standing part 22 is located on the downstream side in the flow direction of the liquid detergent. Therefore, when the pump 30 is operated to feed the liquid from the liquid detergent container 200 to the washing machine 100, the liquid detergent flows upward from below to the first standing portion 21 in the substantially inverted U-shaped arrangement portion of the transparent tube 20, and then the flow direction is changed at the bent portion 23 to flow downward to the second standing portion 22. The liquid detergent detection device 10 is attached to a position on the downstream side in the flow direction of the liquid detergent with respect to the bent portion 23. In the present embodiment, the liquid detergent detection device 10 is attached to the second standing portion 22.

When the washing machine 100 is used, it is necessary to supply an appropriate amount of liquid detergent from the liquid detergent container 200 to the washing machine 100, and the supply amount of the liquid detergent is controlled by the driving time of the pump 30. However, if the remaining amount of the liquid detergent in the liquid detergent container 200 becomes small and air bubbles are mixed in the liquid detergent flowing through the transparent tube 20, the supply amount of the liquid detergent per unit time naturally decreases. In this case, the driving time of the pump 30 is extended to supply an appropriate amount of liquid detergent, compared to the case where no bubble is mixed in the liquid detergent flowing through the transparent tube 20.

In addition, in controlling the supply amount of the liquid detergent based on the driving time of the pump 30, it is necessary to detect the mixing rate of the bubbles in the transparent tube 20. For example, when the mixing rate of bubbles in the liquid detergent fed through the transparent tube 20 is detected to be 50%, the driving time of the pump 30 is doubled, so that the supply amount of the liquid detergent can be set to the same amount as the case where no bubbles are mixed.

As described in the first embodiment, when bubbles are mixed in the liquid detergent flowing through the transparent tube 20, the liquid detergent detection device 10 can detect the presence of the bubbles by distinguishing the region a where the bubbles are not present, the region B where the center of the bubbles are present, and the region C where the end of the bubbles are present. Based on this, the mixing rate of the bubbles in the transparent tube 20 can also be detected.

However, if the mixing ratio of the bubbles in the transparent tube 20 becomes too high, it is needless to say that the time taken to supply a predetermined amount of the liquid detergent increases. In this case, it is preferable to be able to rapidly detect the exhaustion of the liquid detergent in the liquid detergent container 200.

In the washing machine 100 according to the second embodiment, the transparent tube 20 includes the substantially inverted U-shaped arrangement portion (the first standing portion 21, the bending portion 23, and the second standing portion 22), and the liquid detergent detection device 10 is attached to the second standing portion 22 where the liquid detergent flows from top to bottom.

In the process of flowing the liquid detergent from the lower side to the upper side in the first erected portion 21, the liquid detergent is diffused along the inner wall of the transparent tube 20. Further, when the mixing ratio of the bubbles in the transparent tube 20 is high and the amount of the liquid detergent between adjacent bubbles is small, as shown in fig. 5, the liquid detergent between the bubbles spreads along the inner wall of the tube, and thus the vertical width of the liquid detergent decreases. If the width of the liquid detergent is not sufficient to maintain the interface with the bubbles, the liquid detergent forming the interface with the bubbles falls down along the inner wall of the pipe. That is, in the first erected section 21, the small-scale interfaces between the bubbles are extinguished, that is, the defoaming effect is produced.

Further, in the washing machine 100 according to the second embodiment, the bent portion 23 is provided above the first standing portion 21, that is, on the downstream side in the flow direction of the liquid detergent. In the upper portion of the first standing portion 21, the vertical width of the liquid detergent is reduced as described above. When the liquid detergent flows into the bent portion 23, the width direction of the liquid detergent changes from the vertical direction to the horizontal direction. At this time, the width of the liquid detergent in the bent portion 23 in the left-right direction becomes uneven due to gravity. Specifically, the liquid detergent is collected in the lower part of the transparent tube 20 of the curved part 23, and the liquid detergent in the upper part is insufficient. As a result, the liquid detergent cannot maintain the interface with the bubbles at the upper portion of the curved portion 23 in the transparent tube 20, and the interface with the bubbles disappears. Therefore, small-scale interfaces between bubbles can be extinguished, that is, the defoaming effect can be enhanced, by the inside of the bent portion 23.

As a result, the liquid detergent mixed with the bubbles is separated into the liquid detergent and the air by the first standing portion 21 and the bent portion 23, and only large bubbles are sent to the liquid detergent detection device 10. Thus, in the liquid detergent detection apparatus 10, the liquid detergent mixed with many small bubbles is prevented from continuously flowing for a long period of time, and the end of the liquid detergent in the liquid detergent container 200 can be appropriately and accurately detected.

As described above, in a state where bubbles are mixed in the liquid detergent flowing through the transparent tube 20, it is necessary to detect the mixing rate of the bubbles in the transparent tube 20 in order to supply a predetermined amount of the liquid detergent to the washing machine 100. The liquid detergent detection apparatus 10 detects the mixing rate of bubbles in the transparent tube 20, detects each of the above-described regions a to C, calculates the cumulative amounts of the liquid detergent and air from the ratio of these regions, and calculates the mixing rate of bubbles.

However, when the accumulation amounts of the liquid detergent and the air are calculated, the detection error becomes larger even if the actual mixing rates of the bubbles are the same, including more small bubbles. This is because the accumulation calculation of the regions a to C becomes large and the accumulation of errors becomes large in a state where many small bubbles are included. In addition, in a state where many small bubbles are included, the ratio of the region C where both the liquid detergent and the air exist is increased, which also leads to an increase in error.

On the other hand, when the transparent tube 20 is provided with the substantially inverted U-shaped arrangement portion (particularly, the first standing portion 21 and the bent portion 23), the liquid detergent between the bubbles cannot maintain the interface with the bubbles in the process of flowing from the bottom to the top in the first standing portion 21 and in the process of changing the flow direction from the vertical direction to the horizontal direction by the bent portion 23, and a phenomenon occurs in which small bubbles are merged with each other and become large bubbles. That is, even in a state where many small bubbles are included in the first standing part 21, the second standing part 22 provided in the liquid detergent detection device 10 is in a state where the small bubbles are decreased and the large bubbles are increased. As a result, the detection accuracy of the mixing rate of the bubbles in the transparent tube 20 can be improved.

As described above, the interface with the air bubbles is largely removed on the downstream side by the first standing portion 21 and the bent portion 23. Therefore, when the pump 30 is stopped, the probability of the presence of the interface between the inside of the transparent tube 20 and the air bubbles at the detection site of the liquid detergent detection device 10 can be significantly reduced. In the above configuration, the liquid detergent that forms the interface with the air bubbles is likely to be attached to the inside of the transparent tube 20 and become contaminated, and the contamination inside the transparent tube 20 can be prevented at the detection site of the liquid detergent detection device 10, and the detection accuracy of the liquid detergent detection device 10 can be maintained.

[ third embodiment ]

In the third embodiment, a preferred mode of use of the washing machine 100 will be described.

As described above, in the washing machine 100, the liquid detergent in the transparent tube 20 is detected by the liquid detergent detection device 10, and thus, the end of the detergent in the liquid detergent container 200 can be detected. When the liquid detergent detection device 10 detects that the detergent is used up, the liquid detergent container 200 is replenished with the liquid detergent by the manager of the washing machine 100 or the like.

However, the liquid detergent is only replenished to the liquid detergent container 200, and at this point in time, the liquid detergent is not filled between the end of the transparent tube 20 on the liquid detergent container 200 side and the liquid detergent detection device 10. Therefore, when the washing machine 100 is used in such a state, even if the pump 30 is operated to supply the liquid detergent, the liquid detergent does not reach the liquid detergent detection device 10 for a while, and there is a possibility that the liquid detergent detection device 10 detects the end of the detergent again.

In the washing machine 100 according to the third embodiment, the liquid detergent detection device 10 detects that the detergent is used up, and the administrator of the washing machine 100 performs an operation after error release by performing a detergent-use-up error release operation (a predetermined button operation or the like) after replenishing the liquid detergent in the liquid detergent container 200. The post-error-relief operation includes at least an initial filling operation of the transparent tube 20.

Such an initial filling operation is performed by operating the pump 30 until the liquid detergent is filled into the transparent tube 20. Specifically, the pump 30 is operated to start filling the transparent tube 20 with the liquid detergent, and the liquid detergent detection device 10 operates the pump 30 for a predetermined time after detecting the presence of the liquid detergent. This enables the liquid detergent to be filled up to the tip of the transparent tube 20 (the end on the washing machine main body 110 side).

In the initial filling operation, the liquid detergent detection device 10 does not perform the detection operation for a predetermined time after the start of the operation of the pump 30, and may start the detection operation after the elapse of the predetermined time. This is because, even if the pump 30 is operated in a state where the transparent tube 20 does not contain liquid detergent, the liquid detergent does not reach the liquid detergent detection device 10 in a short time, and it is considered that the detection operation is not necessary. Therefore, it is estimated that the detection operation of the liquid detergent detection device 10 is stopped until the liquid detergent detection device 10 does not reach the liquid detergent, and thus wasteful operation of the liquid detergent detection device 10 can be suppressed.

In the initial filling operation, it is preferable to provide a predetermined timeout period from the start of the operation of the pump 30 to the detection of the liquid detergent by the liquid detergent detection device 10, and to end the initial filling operation and detect the end of the detergent again when the liquid detergent is not detected within the timeout period. Thus, for example, it is possible to avoid a situation in which the manager of the washing machine 100 performs the detergent end error release operation without replenishing the liquid detergent to the liquid detergent container 200, and only the pump 30 continues to operate in a state in which the transparent tube 20 is not filled with the detergent.

Further, in the initial filling operation, the liquid detergent detection device 10 detects the presence of the liquid detergent until the liquid detergent is completely filled to the front end (the end on the washing machine main body 110 side) of the transparent tube 20, and then operates the pump 30 for a predetermined time. In this case, it is considered that some liquid detergent is put in the washing tub of the washing machine body 100 at the end point of the initial filling motion. Therefore, it is preferable that the post-error-release operation includes a washing tub cleaning operation of the washing machine main body 110, and the washing tub cleaning operation is performed after the initial filling operation.

In the washing machine 100, as shown in fig. 6, for example, it is preferable that a portion of the transparent tube 20 on the downstream side of the liquid detergent detection device 10 has a length, and when the liquid detergent detection device 10 detects that the liquid detergent is used up, a predetermined amount (preferably, an amount of one washing) of the liquid detergent is secured in the transparent tube 20 on the downstream side of the liquid detergent detection device 10. In this configuration, even if the end of the liquid detergent is detected during use of the washing machine 100 by the user, the amount of liquid detergent required for one-time washing is secured in the transparent tube 20, and it is possible to avoid a situation where the user is not enough liquid detergent due to the cost of putting the liquid detergent in the transparent tube. The method of securing a predetermined amount of liquid detergent in the transparent tube 20 is not particularly limited, and a method of providing a reserve tank in the middle of the transparent tube 20, for example, may be considered, in addition to the length of the transparent tube 20.

In the washing machine 100 described in the first to third embodiments, the type of the pump 30 used for feeding the liquid detergent is not particularly limited, and different effects are produced depending on the type of the pump 30 used. For example, in the case of the type in which the pump 30 does not generate pulsation, the speed variation becomes small in the liquid detergent flowing through the transparent pipe 20. In this case, in a state where the liquid detergent flowing through the transparent tube 20 is mixed with bubbles, the detection accuracy of the mixing rate of the bubbles in the transparent tube 20 becomes high. On the other hand, in the case of the type in which the pump 30 generates pulsation, the speed change becomes large in the liquid detergent flowing through the transparent pipe 20. In this case, in the process of intermittently generating acceleration/deceleration in the flow of the liquid detergent in the transparent tube 20, the bubbles become easily broken, and the bubble removing effect on the first erected portion 21 of the transparent tube 20 is enhanced.

The embodiments disclosed herein are merely exemplary in all respects and are not intended to be construed as limiting. Therefore, the technical scope of the present invention is defined not by the above-described embodiments but by the description of the claims. Further, the meaning equivalent to the claims and all modifications within the scope are included.