Water level detection device, water level detection device design method and cleaning machine

Abstract

The invention relates to a water level detection device, which comprises a light guide column, a light emitter and a light receiver, one end of the light guide column is circumferentially provided with a reflective surface which is inclined relative to the axial direction of the light guide column, and the light emitter and the light receiver face the reflective surface and are respectively arranged on two sides of the central axis of the light guide column. Light rays emitted by the light emitter can be continuously reflected by the reflective surface to be detected and received by the light receiver; and the reflective surface is concave-convex. The water level detection device can solve the problem that bubbles adhere to the reflection end face, and meanwhile signal detection reliability is considered. The invention further relates to a design method of the water level detection device. The roughness of the reflective surface and the light intensity return rate of the reflective surface are designed in a balanced mode based on the application environment. The invention further relates to a cleaning machine which comprises a sewage tank, the water level detection device is arranged in the sewage tank, the end, provided with the light reflecting face, of the light guide column extends to the position, for detecting the water level, in the sewage tank, and the light emitter and the light receiver are both in electric signal connection with the controller.

Description

Technical Field

[0001] The invention relates to a water level detection device, a design method of a water level detection device and a cleaning machine. Background Art

[0002] A detection device is usually provided in the water tank to detect whether the water level has reached a set water level.

[0003] The current mainstream detection device solution is to detect through two electrodes, that is, to extend the electrodes to the water level to be detected. When the water level to be detected is reached, the two electrodes are connected based on water, and when the water level is lower than the water level to be detected, the two electrodes are disconnected. The motor in this detection device needs to be made of conductive materials, usually stainless steel, phosphor bronze and other metal materials, but it is easy to cause electrochemical corrosion and fail when used in high humidity and current scenes.

[0004] Another detection device scheme uses a photoelectric detection module to detect the water level, such as the Chinese utility model patent "A water tank based on photoelectric principle for detecting water level" with authorization announcement number CN217605066U (application number 202221763207.0), in which a photoelectric sensing module is set in the water tank body disclosed, and the detection probe on the photoelectric sensing module goes deep into the water intake cavity. When the liquid level in the water storage cavity reaches the set liquid level or higher than the set liquid level, the detection probe contacts the water body, and when the liquid level in the water storage cavity is lower than the set liquid level, the detection probe contacts the air. The photoelectric sensing module 2 includes a light-transmitting component 202, a photoelectric detection circuit board 205, and two groups (or one group, three groups or more) of photoelectric transceiver components. The optoelectronic transceiver assembly includes a light emitting component 203 for emitting detection light A and a light receiving component 204 for receiving detection light A. The light emitting component 203 and the light receiving component 204 are electrically connected to the photoelectric detection circuit board 205 respectively. The light-transmitting component 202 is provided with a first reflecting part 2021 and a second reflecting part 2022, which are respectively reflective. The first reflecting part 2021 and the second reflecting part 2022 are respectively planar structures arranged on the light-transmitting component 202. The detection light A emitted by the light emitting component 203 reaches the first reflecting part 2021, the detection light A reflected by the first reflecting part 2021 reaches the second reflecting part 2022, and the detection light A reflected by the second reflecting part 2022 reaches the light receiving component 204. After receiving the detection light A, the light receiving component 204 generates a corresponding liquid level electrical signal and feeds it back to the photoelectric detection circuit board 205. When the liquid level in the water storage chamber 101 reaches the set liquid level or is higher than the set liquid level, the detection probe (the first reflection part 2021 and the second reflection part 2022) is in contact with the air, and the reflectivity of each reflection part to the detection light A is high. Most of the detection light A reaches the light receiving component 204 through the reflection effect of the first and second reflection parts. At this time, the light receiving component 204 presents a low resistance state, and the photoelectric detection circuit board 205 outputs a high level close to the power supply voltage to the control module 3. The control module 3 recognizes that the liquid level in the water storage chamber 101 reaches the set liquid level or is higher than the set liquid level; when the storage When the liquid level in the water cavity 101 is lower than the set liquid level, the detection probe (the first reflector 2021 and the second reflector 2022) contacts the water body, and the reflectivity of each reflector to the detection light A is low. Most of the detection light A is refracted by the first and second reflectors and enters the water body in the water storage cavity. Only a small part of the detection light A reaches the light receiving component 204. At this time, the light receiving component 204 is in a high-resistance state, and the photoelectric detection circuit board 205 outputs a low level below 0.1V to the control module 3, and the control module 3 recognizes that the liquid level in the water storage cavity 101 is lower than the set liquid level. The light-transmitting component in the photoelectric detection module has a smooth inclined surface, and the problem of bubble adhesion is easy to occur during use, resulting in the failure of its ability to detect the water level. Summary of the invention

[0005] The first technical problem to be solved by the present invention is to provide a water level detection device for the above-mentioned prior art, which can solve the problem of bubble adhesion on the reflective end surface and take into account the reliability of signal detection.

[0006] The second technical problem to be solved by the present invention is to provide a method for designing a water level detection device that can effectively balance the bubble adhesion and light flux loss on the reflective end face in view of the above-mentioned prior art.

[0007] The third technical problem to be solved by the present invention is to provide a cleaning machine using the above-mentioned water level detection device in view of the above-mentioned prior art.

[0008] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: a water level detection device, including a light guide column, a light emitter, and a light receiver, characterized in that: one end of the light guide column is circumferentially provided with a reflective surface inclined relative to the axial direction of the light guide column, the light emitter and the light receiver are arranged facing the reflective surface and are respectively arranged on both sides of the central axis of the light guide column, the light emitted by the light emitter can be detected and received by the light receiver after continuous reflection from the reflective surface; the reflective surface is arranged concave and convex.

[0009] As an improvement, the roughness of the reflective surface is in the range of 40 μm to 60 μm, and the light reflectivity of the reflective surface is in the range of 0.5 to 0.7.

[0010] Preferably, the roughness of the reflective surface is 50 μm, and the light reflectivity of the reflective surface is 0.6.

[0011] Optionally, at least two grooves arranged along the circumferential direction are arranged on the reflective surface at intervals along the radial direction.

[0012] Optionally, the reflective surface is provided with a plurality of radially distributed bosses protruding outwardly.

[0013] Preferably, a plurality of groups of outwardly protruding bosses are evenly distributed along the circumferential direction on the reflective surface, and a plurality of bosses in each boss group are distributed along the radial direction of the reflective surface.

[0014] Optionally, the outer surface of the reflective surface is concavely provided with a plurality of pits distributed in a radial shape.

[0015] Preferably, a plurality of groups of pits are evenly distributed along the circumferential direction on the reflective surface, and a plurality of pits in each group of pits are distributed along the radial direction of the reflective surface.

[0016] The technical solution adopted by the present invention to solve the above second technical problem is: a method for designing a water level detection device, characterized in that: the water level detection device as described above is adopted;

[0017] The reflective surface includes an outwardly convex protrusion and an inwardly concave depression, wherein the protrusion includes a first side extending in a vertical direction, a convex platform extending in an inclined direction, and a second side extending in a horizontal direction;

[0018] The first side edge and the second side edge respectively constitute a side edge of a recessed portion located on both sides of the protruding portion, and the recessed portion further includes a concave bottom surface extending along an inclined direction;

[0019] The distance between the first side is L1, the distance between the second side is L2, the distance between the convex table surface is L3, and the distance between the concave bottom surface is L4;

[0020] The roughness of the reflective surface Ra=[(2*L3+2*L1 / √2)*(L1 / √2) / 2] / [2*L1 / √2+L3+L4];

[0021] The light intensity return rate of the reflective surface A=1-[L1 / (L3 / √2+L1)];

[0022] The roughness of the reflective surface and the light intensity return rate of the reflective surface are designed in a balanced manner based on the application environment, and L1, L2, L3, and L4 are determined based on the roughness of the reflective surface and the light intensity return rate of the reflective surface.

[0023] Preferably, in a water environment where bubbles are generated, the design parameters of L1, L2, L3, and L4 are adjusted to increase the roughness of the reflective surface, while the light intensity return rate of the reflective surface is reduced.

[0024] As an improvement, the roughness range of the reflective surface is designed to be 40 μm to 60 μm, and the light reflectivity range of the reflective surface is designed to be 0.5 to 0.7.

[0025] Preferably, the roughness of the reflective surface is designed to be 50 μm, and the light reflectivity of the reflective surface is designed to be 0.6.

[0026] The technical solution adopted by the present invention to solve the third technical problem mentioned above is: a cleaning machine, including a body, a controller, and a sewage tank arranged on the body, characterized in that: a water level detection device as described in any one of claims 1 to 8 is arranged in the sewage tank, one end of the light guide column with a reflective surface extends to the position for detecting the water level in the sewage tank, and the light emitter and the light receiver are both connected to the controller with electrical signals.

[0027] As an improvement, the sewage tank includes a box body with an upward opening and a cover body covering the opening, the upper end of the light guide column is connected to the cover body, the lower end of the light guide column is provided with the reflective surface, and the light emitter and light receiver are arranged on the cover body corresponding to the connection position of the light guide column.

[0028] Compared with the prior art, the advantages of the present invention are as follows: the water level detection device of the present invention sets the reflective surface concave and convex, thereby increasing the roughness of the reflective surface, which can effectively prevent bubbles in the water from adhering to the reflective surface during the detection process, thereby causing the water level detection to fail. At the same time, the concave-convex structure can also ensure the detectable amount of reflection, thereby achieving effective detection. The water level detection device overcomes the problem of water level detection failure caused by bubbles, and the water level detection is more reliable.

[0029] The water level detection device design method of the present invention balances the roughness of the reflective surface and the light intensity return rate of the reflective surface based on the application environment, and controls the amount of total reflected light to ensure normal detection of the water level while solving the problem of bubble adhesion caused by the smooth end surface. The design can better adapt to the use environment of the water level detection device.

[0030] The cleaning machine in the present invention uses the aforementioned water level detection device, which can ensure the reliability of water level detection and avoid abnormalities or failures caused by water level detection failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional view of the first water level detection device in the embodiment of the present invention.

[0032] Figure 2 It is a stereoscopic diagram of a second water level detection device in an embodiment of the present invention.

[0033] Figure 3 It is a stereoscopic diagram of a third water level detection device in an embodiment of the present invention.

[0034] Figure 4 It is a three-dimensional cross-sectional view of a cleaning machine in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below with reference to the accompanying drawings.

[0036] like Figures 1 to 4 As shown, the water level detection device in this embodiment includes a light guide column 1, a light transmitter, and a light receiver.

[0037] A reflective surface 11 inclined relative to the axial direction of the light guide column 1 is provided at one end of the light guide column 1 along the circumferential direction. The light emitter and the light receiver are arranged facing the reflective surface 11 and are respectively arranged on both sides of the central axis of the light guide column 1. The light emitted by the light emitter can be detected and received by the light receiver after continuous reflection from the reflective surface 11. The light emitted by the light emitter is usually arranged to be parallel to the axis of the light guide column 1. In order to ensure that the light receiver can reliably receive the light emitted by the light emitter through the reflective surface 11, the angle between the inclined direction of the reflective surface 11 and the axis of the light guide column 1 is 45 degrees. In this way, the light emitted vertically by the light emitter is reflected by the reflective surface 11 on the emitting side and propagates horizontally, and then reflected by the reflective surface 11 on the receiving side and propagates vertically, and is received by the light receiver.

[0038] The reflective surface 11 in the prior art is usually a smooth plane. If bubbles are often generated in the water environment to be detected, if bubbles are attached to the reflective surface 11 during detection, the water level detection will fail. The reflective surface 11 in this embodiment is arranged in a concave and convex manner, that is, the roughness of the reflective surface 11 is enhanced. For a reflective surface 11 with a certain roughness, bubbles are not easy to attach to such a reflective surface 11, thereby solving the problem of water level detection failure caused by bubbles attached to the reflective surface 11. However, increasing the roughness of the reflective surface 11 will inevitably cause a part of the light emitted by the light transmitter to pass through the reflective surface 11, and the effect of total reflection cannot be achieved, and then the light flux received by the light receiver will be reduced, and the corresponding light intensity value detected will decrease. At the same time, in order to avoid the situation where the light intensity value detected by the light receiver is too low and affects the water level detection. It is necessary to design the reflective surface 11 to balance the roughness and light reflectivity of the reflective surface 11.

[0039] The reflective surface 11 in this embodiment includes an outwardly convex protrusion 111 and an inwardly concave concave portion 112. The protrusion 111 includes a first side extending in the vertical direction, a boss 13 surface extending in the inclined direction, and a second side extending in the horizontal direction. The first side and the second side respectively constitute a side of the concave portion 112 located on both sides of the protrusion 111, and the concave portion 112 also includes a concave bottom surface extending in the inclined direction. The light emitted by the light emitter will directly pass through the second side, and will be reflected by the boss 13 surface and the concave bottom surface and received by the light receiver. The distance of the first side is L1, the distance of the second side is L2, the distance of the boss 13 surface is L3, and the distance of the concave bottom surface is L4. Based on the application environment, the specific data of L1, L2, L3, and L4 are designed, and then the roughness of the reflective surface 11 and the light intensity return rate of the reflective surface 11 are balanced.

[0040] According to the specific application environment, the roughness of the reflective surface 11 ranges from 40 μm to 60 μm, and the light reflectivity of the reflective surface 11 ranges from 0.5 to 0.7. In this embodiment, the roughness of the reflective surface 11 is preferably 50 μm, and the light reflectivity of the reflective surface 11 is 0.6.

[0041] In addition, the reflective surface 11 may include a variety of structural designs. In this embodiment, the following three structural embodiments are given, and one is selected according to specific needs.

[0042] like Figure 1 As shown, the first structure of the reflective surface 11 is as follows: at least two circumferentially arranged grooves 12 are arranged on the reflective surface 11 at intervals in the radial direction.

[0043] like Figure 2 As shown, the second structure of the reflective surface 11 is: a plurality of bosses 13 are radially distributed on the reflective surface 11. In order to facilitate parameter design, a plurality of boss groups are evenly distributed along the circumference of the reflective surface 11, and the bosses 13 in each boss group are distributed along the radial direction of the reflective surface 11.

[0044] like Figure 3 As shown, the third structure of the reflective surface 11 is: a plurality of radially distributed pits 14 are recessed on the outer surface of the reflective surface 11. In order to facilitate parameter design, a plurality of pit groups are evenly distributed along the circumference of the reflective surface 11, and the plurality of pits 14 in each pit group are distributed along the radial direction of the reflective surface 11.

[0045] The aforementioned design method of the water level detection device is specifically as follows: the reflective surface 11 includes an outwardly convex protrusion 111 and an inwardly concave depression 112, the protrusion 111 includes a first side extending in the vertical direction, a boss 13 surface extending in the inclined direction, and a second side extending in the horizontal direction. The first side and the second side respectively constitute a side of the depression 112 located on both sides of the protrusion 111, and the depression 112 also includes a concave bottom surface extending in the inclined direction. The distance of the first side is L1, the distance of the second side is L2, the distance of the boss 13 surface is L3, and the distance of the concave bottom surface is L4.

[0046] Correspondingly, the roughness Ra of the reflective surface 11 is [2*L3+2*L1 / √2*L1 / √2 / 2] / [2*L1 / √2+L3+L4]. The light intensity return rate A of the reflective surface 11 is [1-[L1 / L3 / √2+L1]. In this way, the roughness of the reflective surface 11 and the light intensity return rate of the reflective surface 11 are designed in a balanced manner based on the application environment, and then reasonable L1, L2, L3, and L4 are determined based on the roughness of the reflective surface 11 and the light intensity return rate of the reflective surface 11.

[0047] For example, in a water environment where no bubbles will be generated, the roughness can be designed to be 0, that is, the reflective surface 11 is a smooth plane, but bubbles are inevitable in the water environment, so it is necessary to increase the roughness of the reflective surface 11. That is, in a water environment where bubbles are generated, the design parameters of L1, L2, L3, and L4 are adjusted to increase the roughness of the reflective surface 11, and at the same time, the light intensity return rate of the reflective surface 11 will decrease.

[0048] The roughness of the reflective surface 11 is designed to be in the range of 40 μm to 60 μm, and the light reflectivity of the reflective surface 11 is designed to be in the range of 0.5 to 0.7. In this embodiment, the roughness of the reflective surface 11 is preferably designed to be 50 μm, and the light reflectivity of the reflective surface 11 is designed to be 0.6. This design parameter is particularly suitable for the sewage tank 5 of the cleaning machine described below, thereby realizing the detection of the water level in the sewage tank 5.

[0049] like Figure 4 As shown, the present invention also relates to a cleaning machine, including a machine body 4, a controller, a sewage tank 5 arranged on the machine body 4, the sewage tank 5 is provided with the aforementioned water level detection device, one end of the light guide column 1 provided with the reflective surface 11 extends to the position for detecting the water level in the sewage tank 5, and the light emitter and the light receiver are both connected to the controller by electrical signals. Specifically, the sewage tank 5 includes a box body 51 with an upward opening and a cover body 52 covering the opening, the upper end of the light guide column 1 is connected to the cover body 52, the lower end of the light guide column 1 is provided with the reflective surface 11, and the light emitter and the light receiver are arranged on the cover body 52 corresponding to the connection position of the light guide column 1.

[0050] The water level detection device of the present invention sets the reflective surface 11 in a concave-convex manner, thereby increasing the roughness of the reflective surface 11, which can effectively prevent bubbles in the water from adhering to the reflective surface 11 during the detection process, thereby causing the water level detection to fail. At the same time, the concave-convex structure can also ensure the detectable amount of reflection, thereby achieving effective detection. The water level detection device overcomes the problem of water level detection failure caused by bubbles, and the water level detection is more reliable.

[0051] The water level detection device design method of the present invention balances the roughness of the reflective surface 11 and the light intensity return rate of the reflective surface 11 based on the application environment, and controls the amount of total reflected light to ensure normal detection of the water level while solving the problem of bubble adhesion caused by the smooth end surface. The design can better adapt to the use environment of the water level detection device.

[0052] The cleaning machine in the present invention uses the aforementioned water level detection device, which can ensure the reliability of water level detection and avoid abnormalities or failures caused by water level detection failure.

[0053] In the specification and claims of the present invention, terms indicating directions, such as "front", "rear", "up", "down", "left", "right", "side", "top", "bottom", etc., are used to describe various exemplary structural parts and elements of the present invention, but these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only used as explanations and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

Claims

1. A water level detection device, comprising a light guide column (1), a light transmitter, and a light receiver, characterized in that: A reflective surface (11) is arranged along the circumferential direction at one end of the light guide column (1) and is inclined relative to the axial direction of the light guide column (1); the light emitter and the light receiver are arranged facing the reflective surface (11) and are respectively arranged on both sides of the central axis of the light guide column (1); the light emitted by the light emitter can be continuously reflected by the reflective surface (11) and detected and received by the light receiver; the reflective surface (11) is arranged in a concave and convex manner.

2. The water level detection device according to claim 1, characterized in that: The roughness of the reflective surface (11) is in the range of 40 μm to 60 μm, and the light reflectivity of the reflective surface (11) is in the range of 0.5 to 0.

7.

3. The water level detection device according to claim 2, characterized in that: The roughness of the reflective surface (11) is 50 μm, and the light reflectivity of the reflective surface (11) is 0.

6.

4. The water level detection device according to any one of claims 1 to 3, characterized in that: At least two grooves (12) arranged in the circumferential direction are arranged on the reflective surface (11) at intervals in the radial direction.

5. The water level detection device according to any one of claims 1 to 3, characterized in that: The reflective surface (11) is provided with a plurality of bosses (13) which are radially distributed.

6. The water level detection device according to claim 5, characterized in that: The reflective surface (11) is provided with a plurality of groups of outwardly protruding bosses evenly distributed along the circumferential direction, and a plurality of bosses (13) in each boss group are distributed along the radial direction of the reflective surface (11).

7. The water level detection device according to any one of claims 1 to 3, characterized in that: The outer surface of the reflective surface (11) is provided with a plurality of recessed pits (14) distributed in a radial shape.

8. The water level detection device according to claim 7, characterized in that: The reflective surface (11) has a plurality of groups of pits evenly distributed along the circumferential direction, and a plurality of pits (14) in each group of pits are distributed along the radial direction of the reflective surface (11).

9. A method for designing a water level detection device, characterized in that: Using the water level detection device as described in any one of claims 1 to 8; The reflective surface (11) comprises an outwardly convex protrusion (111) and an inwardly concave depression (112); the protrusion (111) comprises a first side edge extending in a vertical direction, a boss (13) surface extending in an inclined direction, and a second side edge extending in a horizontal direction; The first side edge and the second side edge respectively constitute a side edge of a recessed portion (112) located on both sides of the protruding portion (111), and the recessed portion (112) further comprises a concave bottom surface extending in an inclined direction; The distance between the first side edge is L1, the distance between the second side edge is L2, the distance between the boss (13) surface is L3, and the distance between the concave bottom surface is L4; The roughness of the reflective surface (11) is Ra=[(2*L3+2*L1 / √2)*(L1 / √2) / 2] / [2*L1 / √2+L3+L4]; The light intensity return rate of the reflective surface (11) is A=1-[L1 / (L3 / √2+L1)]; The roughness of the reflective surface (11) and the light intensity return rate of the reflective surface (11) are balanced and designed based on the application environment, and L1, L2, L3, and L4 are determined based on the roughness of the reflective surface (11) and the light intensity return rate of the reflective surface (11).

10. The method for designing a water level detection device according to claim 9, characterized in that: In a water environment where bubbles are generated, the design parameters of L1, L2, L3, and L4 are adjusted to increase the roughness of the reflective surface (11), while the light intensity return rate of the reflective surface (11) is reduced.

11. The method for designing a water level detection device according to claim 9, characterized in that: The roughness range of the reflective surface (11) is designed to be 40 μm to 60 μm, and the light reflectivity range of the reflective surface (11) is designed to be 0.5 to 0.

7.

12. The method for designing a water level detection device according to claim 9, characterized in that: The roughness of the reflective surface (11) is designed to be 50 μm, and the light reflectivity of the reflective surface (11) is designed to be 0.

6.

13. A cleaning machine, comprising a machine body (4), a controller, and a sewage tank (5) arranged on the machine body (4), characterized in that: The sewage tank (5) is provided with a water level detection device as claimed in any one of claims 1 to 8, one end of the light guide column (1) provided with a reflective surface (11) extends to a position in the sewage tank (5) for detecting the water level, and the light emitter and the light receiver are both connected to the controller by electrical signals.

14. The cleaning machine according to claim 13, characterized in that: The sewage tank (5) comprises a box body (51) with an upward opening and a cover body (52) covering the opening; the upper end of the light guide column (1) is connected to the cover body (52); the lower end of the light guide column (1) is provided with the reflective surface (11); and the light emitter and the light receiver are arranged on the cover body (52) corresponding to the connection position of the light guide column (1).

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