WO2019091133A1

WO2019091133A1 - Self-cleaning assembly, camera and self-cleaning method

Info

Publication number: WO2019091133A1
Application number: PCT/CN2018/095538
Authority: WO
Inventors: 刘佳; 杨传枫; 曹金灿
Original assignee: 华为技术有限公司
Priority date: 2017-11-09
Filing date: 2018-07-13
Publication date: 2019-05-16
Also published as: CN109759368B; CN109759368A

Abstract

Provided in an embodiment of the present application is a self-cleaning assembly applicable to a camera. The self-cleaning assembly comprises an end cover, a cleaning brush and a semiconductor refrigeration sheet, and the end cover is provided with a lens. The cleaning brush is connected with the end cover in a rotating manner, and the semiconductor refrigeration sheet is used to generate condensed water. During the rotation of the cleaning brush, the condensed water is carried to flow through the lens and to clean the lens. The above self-cleaning assembly does not wear the lens and has a good cleaning effect. Also provided in the embodiment of the present application are the camera and a self-cleaning method.

Description

Self-cleaning components, cameras and self-cleaning methods

Technical field

The present application relates to the field of security equipment, and in particular, to a self-cleaning component, a camera, and a self-cleaning method.

Background technique

At present, with the increasing demand for security in the process of globalization, the video surveillance industry has entered a rapid development channel. During the long-term outdoor operation of the camera, the lens in front of the lens is often dirty due to dust, rain, fog, oil, etc., resulting in poor image quality, so the image quality is not guaranteed. In order to achieve self-cleaning of the lens, mainstream camera manufacturers propose to add a wiper on the top of the lens, and use a wiper to remove the dirt of the lens. However, the wiper has a large friction with the glass surface in a dry environment, and it is easy to scratch the lens, and the wiper can only clean the dust on the lens, and the cleaning effect on oil stains, bird droppings, etc. is poor.

Summary of the invention

The present application provides a self-cleaning assembly that does not wear the lens and has a good cleaning effect, a video camera, and a self-cleaning method.

In a first aspect, a self-cleaning assembly is provided. The self-cleaning assembly is applied to a camera. The self-cleaning assembly includes an end cap, a cleaning brush, and a semiconductor refrigeration sheet. The end cap is provided with a lens. The cleaning brush is rotatably coupled to the end cap. In other words, the cleaning brush is mounted on the end cap and the cleaning brush is rotatable relative to the end cap. The semiconductor refrigeration sheet is used to produce condensed water. When the semiconductor refrigerating sheet is electrically cooled, the water vapor in the air is cooled to generate condensed water. During the rotation of the cleaning brush, the condensed water is carried through the lens to clean the lens. In other words, the range of rotation of the cleaning brush covers the lens such that the cleaning brush can pass the lens while rotating to clean the lens.

The self-cleaning assembly refrigerates through the semiconductor refrigerating sheet to condense water vapor in the air to form the condensed water, and carries the condensed water through the lens through the cleaning brush, thereby enabling cleaning of the lens with water. When the cleaning brush removes the lens with water, the lens is not worn, so that the camera applying the self-cleaning component has a long service life and has a good cleaning effect, and can effectively remove the lens. The oil, bird droppings, etc. are dirty. In short, the self-cleaning assembly can self-produce the condensed water through the semiconductor refrigeration sheet when needed, and clean the lens by the cleaning brush, thereby achieving self-cleaning and good cleaning effect. The camera can be operated normally for a long time and the daily maintenance cost is low.

In conjunction with the first aspect, in a first possible implementation of the first aspect, the cleaning brush includes a rotating shaft, a bracket, and a brush head. The bracket is rotatably coupled to the end cap by the rotating shaft. The bracket includes oppositely disposed rotating ends and movable ends. The rotating shaft is coupled to the rotating end of the bracket to rotate the movable end about the rotating end. The brush head is secured to a side of the bracket that faces the end cap. The brush head is made of a water absorbing material. Water absorbing materials include, but are not limited to, absorbent cotton, silica gel, sponge, water absorbing resin, water absorbing rubber, and the like.

Since the brush head is made of a water absorbing material, the brush head can quickly absorb the condensed water generated by the semiconductor refrigerating sheet, thereby carrying the condensed water to clean the lens. Of course, in other possible implementations, the brush head may also adopt a material that is less hygroscopic, but still has a certain hydrophilicity, such as plastic, so that the cleaning brush can still carry the condensed water during the rotation process. Clean the lens.

Optionally, the self-cleaning assembly further includes a driving member for driving the rotating shaft to drive the bracket to rotate. The drive member can be a motor. The drive member is located on a side of the end cap that is remote from the cleaning brush.

Optionally, the lens is secured to the end cap by assembly. The end cover is provided with a through hole, the lens is a component independent of the end cover, and the lens is embedded in the through hole or covers an opening at one end of the through hole to be fixed to the end cover. For example, the lens is embedded in the through hole, and the periphery of the lens and the hole wall of the through hole are bonded by an adhesive. Alternatively, the hole wall of the through hole is provided with a limiting surface. The lens is received in the through hole, and the lens abuts the limiting surface. The limiting surface is bonded to the periphery of the lens by a double-sided tape or an adhesive. The limiting surface may face the cleaning brush to facilitate fixing the lens, or the limiting surface may face away from the cleaning brush to prevent the lens from falling.

Alternatively, the lens is part of the end cap. The end cap also includes a shaded area surrounding the perimeter of the lens. The lens is made of a transparent material to allow light to pass through. The shielding area is made of a light shielding material to achieve a shielding effect. The end cap can be integrally formed by a buried molding process or a two-shot molding process.

In conjunction with the first aspect or the first possible implementation of the first aspect, in a second possible implementation of the first aspect, the lens faces the mirror of the cleaning brush and the end cap faces the cleaning brush The outer surface is flush. At this time, since the mirror surface of the lens is flush with the outer surface of the end cap, an area where dirt is easily collected is not formed on the periphery of the lens, so that the cleaning brush can smoothly clean the mirror surface of the lens. And the cleaning efficiency is high and the cleaning effect is good.

Optionally, the mirror surface of the lens is covered with a hydrophobic coating, so that after the lens is covered with dust, the dust can be smoothly drained by water (including but not limited to the condensed water, rainwater generated by the semiconductor refrigeration sheet, Dew, etc.) is carried away to keep the mirror surface of the lens relatively clean.

Optionally, the outer casing is connected to a circumference of the end cover. The outer casing and the end cover together define an accommodating space. The camera body is received in the accommodating space. The lens is disposed in the accommodating space adjacent to the end cap to face the lens.

The semiconductor refrigerating sheet may be fixed to the end cap, or fixed to the cleaning brush, or located on a side of the end cap away from the cleaning brush (for example, fixed to the outer casing). When the semiconductor refrigerating sheet is fixed on the outer casing, it may be accommodated in the accommodating space or may be located outside the accommodating space. When the semiconductor refrigeration sheet generates the condensed water at any of the above positions, the condensed water may directly or indirectly contact the cleaning brush or flow through the rotation range of the cleaning brush or flow through the lens, so that the A cleaning brush carries the condensed water to clean the lens.

in particular:

In conjunction with the first aspect or the first possible implementation of the first aspect or the second possible implementation of the first aspect, in a third possible implementation of the first aspect, the end cap is provided with a receiving slot. The semiconductor refrigerating sheet is housed in the receiving groove. The receiving groove is located within a rotation range of the cleaning brush. The cold end of the semiconductor refrigerating sheet is disposed adjacent to an outer surface of the end cap, and a hot end of the semiconductor refrigerating sheet is disposed away from an outer surface of the end cap. In the cold end cooling of the semiconductor refrigerating sheet, the condensed water is formed in the vicinity of the cold end of the semiconductor refrigerating sheet, that is, the condensed water is formed at a region of the end cap close to the semiconductor refrigerating sheet. Since the receiving groove is located within a rotation range of the cleaning brush, the condensed water can be formed in a rotation range of the cleaning brush, so that the condensed water is carried when the cleaning brush rotates. The cleaning brush cleans the lens with water. The self-cleaning component first cools the condensed water by the semiconductor refrigerating sheet, and after the condensed water flows through the rotating range of the cleaning brush, starts the cleaning brush to rotate, so that the cleaning brush carries when rotating The condensed water cleans the lens.

In conjunction with the first aspect or the first possible implementation of the first aspect or the second possible implementation of the first aspect, in a fourth possible implementation of the first aspect, the end cap is provided with a receiving slot. The semiconductor refrigerating sheet is housed in the receiving groove. The receiving groove is located vertically above the lens such that the condensed water passes through the lens under the force of gravity. The cold end of the semiconductor refrigerating sheet is disposed adjacent to an outer surface of the end cap, and a hot end of the semiconductor refrigerating sheet is disposed away from an outer surface of the end cap. The chilled water is formed at a cold end of the semiconductor refrigerating sheet, and the condensed water is formed near a cold end of the semiconductor refrigerating sheet, that is, at a region of the end cap close to the semiconductor refrigerating sheet. Since the receiving groove is located vertically above the lens, the condensed water can be formed vertically above the lens, so that the condensed water passes through the lens under the action of gravity, and the cleaning brush rotates past In the case of the lens, the cleaning brush can carry the condensed water to achieve water cleaning.

The self-cleaning component first cools the condensed water through the semiconductor refrigeration sheet, and the condensed water passes through the lens, and after the mirror surface of the lens is wetted, the cleaning brush is started to rotate, so that the cleaning brush is The condensed water is carried while rotating to clean the lens.

Optionally, the receiving slot is provided with a communication hole away from the bottom wall of the outer surface of the end cover, and the communication hole is configured to allow the power cable of the semiconductor refrigeration chip to pass. The semiconductor refrigerating sheet housed in the receiving groove is electrically connected to the camera body through the power source line.

Optionally, a waterproof gel is filled between the groove wall of the receiving groove and the semiconductor refrigeration sheet to achieve a waterproof seal. Wherein, the waterproof gel can completely wrap the semiconductor refrigeration sheet to protect the semiconductor refrigeration sheet. Of course, the thickness of the portion of the waterproof gel covering the cold end of the semiconductor refrigerating sheet is thinner than the thickness of other portions of the waterproof gel to ensure the cooling effect of the cold end of the semiconductor refrigerating sheet.

In conjunction with the third possible implementation of the first aspect or the fourth possible implementation of the first aspect, in a fifth possible implementation of the first aspect, the cold end of the semiconductor refrigerating sheet has a distance away from the semiconductor refrigeration a condensing surface of the hot end of the sheet, the condensing surface being flush with the outer surface of the end cap facing the cleaning brush. Since the condensation surface is flush with the outer surface of the end cap, condensed water generated on the condensation surface can smoothly flow from the condensation surface to the outer surface of the end cap and the lens The mirror surface is such that there is sufficient condensed water on the mirror surface of the lens to ensure the cleaning efficiency and cleaning effect of the self-cleaning assembly.

In conjunction with the first aspect or the first possible implementation of the first aspect or the second possible implementation of the first aspect, in a sixth possible implementation of the first aspect, the semiconductor refrigerating sheet is fixed to the cleaning Brush it up. The cold end of the semiconductor refrigerating sheet is disposed away from the cleaning brush with respect to the hot end of the semiconductor refrigerating sheet. In the cold end cooling of the semiconductor refrigerating sheet, the condensed water is formed in the vicinity of the cold end of the semiconductor refrigerating sheet, that is, the condensed water is formed at a region of the cleaning brush close to the semiconductor refrigerating sheet. At this time, when the brush head of the cleaning brush is made of a water absorbing material, the condensed water can be quickly absorbed by the brush head, so that the cleaning brush can carry the condensed water to clean the lens. When the brush head of the cleaning brush uses other hydrophilic materials, the condensed water can also penetrate into the brush head to enable the cleaning brush to be cleaned with water.

The self-cleaning component first cools the condensed water by the semiconductor refrigeration sheet, and after the condensed water is absorbed or penetrates into the brush head by the brush head, the cleaning brush is started to rotate, thereby making the cleaning brush The lens is cleaned by carrying the condensed water while rotating, and the cleaning effect is better.

It can be understood that the cleaning brush has an initial position when it is not rotated. The semiconductor refrigerating sheet is fixed at an upper position of the cleaning brush so that the condensed water is better absorbed by the brush head or infiltrated into the brush head by gravity. The semiconductor refrigerating sheet is disposed on an upper portion of the cleaning brush, and the brush head of the cleaning brush is made of a water absorbing material. When the lens needs to be cleaned, the semiconductor refrigerating sheet is energized, the semiconductor refrigerating sheet condenses water vapor to generate the condensed water, the condensed water flows into the water absorbing material, and then the cleaning brush is activated to rotate the cleaning lens.

The hot end of the semiconductor refrigerating sheet may be fixed to the holder of the cleaning brush by bonding or the like. The bracket has a connecting surface away from the brush head, and the connecting surface has a flat area with a large area to facilitate attachment of the hot end of the semiconductor cooling sheet.

In conjunction with the sixth possible implementation of the first aspect, in a seventh possible implementation of the first aspect, the initial position of the cleaning brush is located vertically above the lens such that the condensed water is under gravity Pass the lens. The chilled water is formed in the vicinity of the cold end of the semiconductor refrigerating sheet at the cold end of the semiconductor refrigerating sheet, that is, the condensed water is formed at a region of the cleaning brush adjacent to the semiconductor refrigerating sheet. Since the initial position of the cleaning brush is vertically above the lens, the semiconductor refrigerating sheet is cooled when the cleaning brush is in an initial position, so that the condensed water can be formed vertically above the lens, thereby The condensed water passes through the lens under the action of gravity, and the cleaning brush can carry the condensed water when the cleaning brush rotates through the lens, thereby achieving water cleaning. Moreover, when the brush head of the cleaning brush is made of a water absorbing material or a hydrophilic material, the condensed water can also be sucked into the brush head or penetrate into the brush head at the same time, so that the cleaning brush is cleaned with water. The effect of the lens is better.

The self-cleaning component first cools the condensed water through the semiconductor refrigeration sheet, and the condensed water passes through the lens, and after the mirror surface of the lens is wetted, the cleaning brush is started to rotate, so that the cleaning brush is The condensed water is carried while rotating to clean the lens, so that the cleaning effect is better.

In combination with the first aspect or the first possible implementation of the first aspect or the second possible implementation of the first aspect, in an eighth possible implementation of the first aspect, the self-cleaning assembly further includes a water tank and a water pipe . The semiconductor cooling sheet is housed in the water tank to form the condensed water in the water tank. The water tank is located on a side of the end cap away from the cleaning brush. An inlet end of the water pipe communicates with the water tank, and an outlet end of the water pipe is fixed to the end cover. The outlet end of the water pipe is located within the range of rotation of the cleaning brush. The condensed water is formed in the water tank during cooling of the cold junction of the semiconductor refrigerating sheet. After the water tank collects enough of the condensed water, the water pipe can be turned on when the lens needs to be cleaned, so that the condensed water flows out. Since the outlet end of the water pipe is located within a rotation range of the cleaning brush, the condensed water can flow to a rotation range of the cleaning brush, thereby carrying the condensed water when the cleaning brush rotates, Achieve clean water.

In combination with the first aspect or the first possible implementation of the first aspect or the second possible implementation of the first aspect, in a ninth possible implementation of the first aspect, the self-cleaning assembly further includes a water tank and a water pipe . The semiconductor cooling sheet is housed in the water tank to form the condensed water in the water tank. The water tank is located on a side of the end cap away from the cleaning brush. The inlet end of the water pipe communicates with the water tank. An outlet end of the water tube is secured to the end cap and vertically above the lens such that the condensed water passes the lens under the force of gravity. The condensed water is formed in the water tank during cooling of the cold junction of the semiconductor refrigerating sheet. After the water tank collects enough of the condensed water, the water pipe can be turned on when the lens needs to be cleaned, so that the condensed water flows out. Since the outlet end of the water pipe is vertically above the lens, the condensed water passes through the lens under the force of gravity, and the cleaning brush can carry the cleaning brush as the cleaning brush rotates through the lens Condensate water for clean water.

Optionally, the semiconductor refrigerating sheet may refrigerate to generate the condensed water when the lens needs to be cleaned, or may be in a refrigerating state for a long time, so that the water tank collects enough condensed water to start cleaning at any time. The lens, the emergency response is fast. When the lens needs to be cleaned, the water pipe is turned on to allow the condensed water to flow out, and the cleaning brush achieves water cleaning.

Optionally, the water tank can be received in the accommodating space to improve concealment, so that the camera has a relatively clean appearance. Of course, in other possible implementations, the water tank may also be secured to the outer sidewall of the outer casing to collect a portion of the natural water (eg, rain, dew, etc.).

Alternatively, an on-off valve may be provided at the middle or at least one end of the water pipe to control the on and off states of the water pipe.

In a second aspect, a camera is provided. The camera includes a camera body and a self-cleaning assembly in any one of the possible implementations of the first aspect. The camera body is located on a side of the end cap away from the cleaning brush. The lens of the camera body is disposed opposite the lens. The lens is made of a light transmissive material such that external light can penetrate the lens into the lens. Since the self-cleaning assembly can achieve self-cleaning and good cleaning effect, the camera can operate normally for a long time and the daily maintenance cost is low.

In a third aspect, a self-cleaning method is provided. The self-cleaning method cleans the lens using a self-cleaning assembly in any of the possible implementations of the first aspect to enable the camera to achieve long-term operation and better image quality. The self-cleaning assembly includes an end cap, a cleaning brush, and a semiconductor refrigeration sheet. The end cap is provided with a lens. The cleaning brush is rotatably coupled to the end cap.

The self-cleaning method includes:

The semiconductor refrigeration sheet is cooled to form condensed water.

The cleaning brush is driven to rotate such that the cleaning brush carries the condensed water to clean the lens.

The self-cleaning method is capable of efficiently purifying the lens by cooling the semiconductor chilled water by the semiconductor refrigerating sheet and then driving the cleaning brush to clean the lens when the lens needs to be cleaned, and Cleaning with water is effective and avoids wearing the lens.

The triggering condition for the cooling of the semiconductor refrigerating sheet to form condensed water may be: automatic triggering when there is dirt on the lens, or timing triggering, or manual triggering. Specifically, it is determined whether there is dirt on the lens by image signal processing, and when there is dirt on the lens, the semiconductor refrigeration sheet is automatically triggered to form condensed water. The timing triggering program can be set to automatically trigger the cooling of the semiconductor refrigerating sheet to form condensed water after a certain period of time. The semiconductor refrigerating sheet may be temporarily manually triggered to form condensed water in other environments (e.g., heavy fog, etc.) where cleaning of the lens is required. The above three triggering modes may be selected one, or a combination of a plurality of them may be selected.

In conjunction with the third aspect, in a first possible implementation of the third aspect, the process of cooling the semiconductor refrigerating sheet to form condensed water comprises:

The dew point temperature is calculated based on air temperature and air humidity. The dew point temperature is the temperature at which water vapor in the air is condensed into water. The semiconductor refrigeration chip is provided with a temperature sensor and a humidity sensor for detecting the temperature and humidity of the air. Of course, temperature sensors and humidity sensors can also be provided on other components of the self-cleaning assembly (eg, end caps, etc.).

The cold end of the semiconductor refrigeration sheet is at a first temperature for a first length of time to reduce the air temperature to the dew point temperature. When the air temperature is lowered to the dew point temperature, water vapor in the air begins to condense to form the condensed water.

The cold end of the semiconductor refrigerating sheet continues for a second time at a second temperature to form condensed water, the second temperature being higher than or equal to the first temperature. The cold end of the semiconductor refrigeration sheet continues to be cooled, thereby forming a sufficient amount of the condensed water to ensure the cleaning effect of the self-cleaning method.

Since the air temperature has decreased to the dew point temperature, the second temperature may be equal to the first temperature to form sufficient condensed water as soon as possible, and the second temperature may also be higher than the first temperature, Thereby, the energy consumption of the semiconductor refrigerating sheet is lowered while the condensed water is continuously formed. In the present application, the length of time of the first duration and the length of time of the second duration are not limited, and the first duration and the second duration may be flexibly set according to the temperature and humidity of the air and the demand for cleaning water. set.

In conjunction with the first possible implementation of the third aspect, in a second possible implementation of the third aspect, the process of cooling the semiconductor refrigerating sheet to form condensed water before calculating the dew point temperature further comprises:

Detect the air temperature.

When the air temperature is lower than the first threshold, the semiconductor cooling sheet continues to heat for a third time period to raise the air temperature to a second threshold, the second threshold being greater than the first threshold.

Check the air humidity.

When it is detected that the air temperature is lower than the first threshold, the ambient air temperature is very low, and it is difficult to obtain the condensed water directly by the semiconductor refrigeration sheet, so that the air temperature is raised first by heating. Up to the second threshold, the semiconductor refrigeration sheet can be smoothly condensed to obtain the condensed water.

It will be appreciated that the step of detecting the humidity of the air may be performed simultaneously with the step of detecting the temperature of the air to save detection time. When the air temperature is greater than or equal to the first threshold, the dew point temperature may be calculated according to the detected air temperature and air humidity. If the semiconductor refrigerating sheet still needs to be heated to raise the air temperature to the second threshold, the air humidity needs to be detected again so that the dew point temperature can obtain an accurate value according to the current data.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the drawings to be used in the embodiments of the present application or the background art will be described below.

1 is a schematic structural diagram of a camera provided by an embodiment of the present application;

Figure 2 is another schematic structural view of the camera shown in Figure 1;

3 is a schematic structural view of an embodiment of a self-cleaning assembly of the camera shown in FIG. 1;

4 is a partial structural schematic view of the self-cleaning assembly of the camera shown in FIG. 1;

Figure 5 is a schematic structural view of an embodiment of the structure at A in Figure 2;

Figure 6 is a schematic structural view of an embodiment of the structure at A in Figure 2;

7 is a schematic structural view of another embodiment of the self-cleaning assembly of the camera shown in FIG. 1;

Figure 8 is another schematic structural view of the self-cleaning assembly shown in Figure 7;

9 is a schematic structural view of still another embodiment of the self-cleaning assembly of the camera shown in FIG. 1;

Figure 10 is another schematic structural view of the self-cleaning assembly shown in Figure 9;

11 is a flow chart of a self-cleaning method provided by an embodiment of the present application;

Figure 12 is a detailed flow chart of step 01 of the self-cleaning method shown in Figure 11;

FIG. 13 is a schematic structural view of still another embodiment of the self-cleaning assembly of the camera shown in FIG. 1. FIG.

Detailed ways

The embodiments of the present application are described below in conjunction with the accompanying drawings in the embodiments of the present application.

Referring to FIG. 1 to FIG. 3 , an embodiment of the present application provides a camera 100 . The camera 100 can be a network camera (IP Camera). The camera 100 includes a camera body 200 and a self-cleaning assembly 300. The camera body 200 is used to implement image capture. The camera body 200 is further configured to compress and encrypt data (including but not limited to image data, sound data, etc.) and send it to an end user via a local area network, the Internet, or a wireless network. The camera body 200 mainly includes a lens 201, an image sensor, a sound sensor, an analog-to-digital converter, an image encoder, a processor, a memory, and the like.

Referring to FIG. 1 to FIG. 3 , an embodiment of the present application provides a self-cleaning assembly 300 . The self-cleaning assembly 300 is applied to the camera 100. The self-cleaning assembly 300 includes an end cap 1, a cleaning brush 2, and a semiconductor refrigerating sheet 3. The end cap 1 is provided with a lens 4. The cleaning brush 2 is rotatably coupled to the end cap 1. In other words, the cleaning brush 2 is mounted on the end cap 1 and the cleaning brush 2 is rotatable relative to the end cap 1. The semiconductor refrigerating sheet 3 is used to generate condensed water. When the semiconductor refrigerating sheet 3 is electrically cooled, water vapor in the air is cooled to generate condensed water. During the rotation of the cleaning brush 2, the condensed water is carried through the lens 4 to clean the lens 4. In other words, the range of rotation 20 of the cleaning brush 2 covers the lens 4 such that the cleaning brush 2 can pass the lens 4 while rotating to clean the lens 4.

The camera body 200 is located on a side of the end cover 1 away from the cleaning brush 2. The lens 201 of the camera body 200 is disposed opposite the lens 4. The lens 4 is made of a light transmissive material such that external light can penetrate the lens 4 into the lens 201. The lens 4 can prevent the external light from being significantly changed in the direction of propagation when passing through the lens 4, thereby causing image distortion, and can also protect the lens 201.

In the present embodiment, the self-cleaning assembly 300 is cooled by the semiconductor refrigerating sheet 3 to condense water vapor in the air to form the condensed water, and the condensed water is carried by the cleaning brush 2 through the lens 4, Thereby, the lens 4 can be cleaned with water. When the cleaning brush 2 is cleaned with the water, the lens 4 is not worn, so that the camera 100 applying the self-cleaning assembly 300 has a long service life and has a good cleaning effect and can be effective. The oil stains, bird droppings, and the like on the lens 4 are removed. In short, the self-cleaning assembly 300 can self-produce the condensed water through the semiconductor refrigerating sheet 3 when needed, and clean the lens 4 with water through the cleaning brush 2, thereby realizing self-cleaning of the lens 4. Moreover, the cleaning effect is good, so that the camera 100 can operate normally for a long time and the daily maintenance cost is low.

It can be understood that, referring to FIG. 4 together, the semiconductor refrigerating sheet 3 is made by utilizing the Peltier effect of the semiconductor material. The so-called Peltier effect refers to a temperature difference between the two ends (31, 32) of the galvanic couple 33 when a direct current flows through the galvanic couple 33 composed of two kinds of semiconductor materials, one end absorbs heat and the other end radiates heat. The phenomenon. The semiconductor refrigerating sheet 3 can realize high-precision temperature control through current control, and the thermal inertia is very small, and the cooling and heating time is fast. When the current direction is reversed, the cold and hot ends are also interchanged. In the present application, 31 is a cold end and 32 is a hot end. As shown in FIG. 4, the self-cleaning assembly 300 further includes a controller 301, a power source 302, and a changeover switch 303. The power source 302 is used to supply a DC power source to the semiconductor refrigerating sheet 3. The changeover switch 203 is connected between the power source 302 and the semiconductor refrigerating sheet 3. The controller 301 controls the changeover switch 303 to switch the direction of current flowing through the semiconductor refrigerating sheet 3.

Optionally, referring to FIG. 2, FIG. 3 and FIG. 5, the cleaning brush 2 comprises a rotating shaft 21, a bracket 22 and a brush head 23. The bracket 22 is rotatably coupled to the end cover 1 via the rotating shaft 21. The bracket 22 includes oppositely disposed rotating ends and movable ends. The rotating shaft 21 is coupled to the rotating end of the bracket 22 to rotate the movable end about the rotating end. The movable end rotates around the rotating end to form a rotation range 20 of the cleaning brush 2. The brush head 23 is fixed to a side of the bracket 22 facing the end cap 1. The brush head 23 is made of a water absorbing material. Water absorbing materials include, but are not limited to, absorbent cotton, silica gel, sponge, water absorbing resin, water absorbing rubber, and the like.

In the present embodiment, since the brush head 23 is made of a water absorbing material, the brush head 23 can quickly absorb the condensed water generated by the semiconductor refrigerating sheet 3, thereby carrying the condensed water to clean the lens 4. . Of course, in other embodiments, the brush head 23 can also adopt a material that is poor in water absorption, but still has certain hydrophilicity, such as plastic, and the condensed water can penetrate into the brush head 23, so that the cleaning is performed. The brush 2 is still capable of carrying the condensed water to clean the lens 4 during rotation.

It can be understood that, as shown in FIG. 3 and FIG. 13 , in the case that the rotation range 20 of the cleaning brush 2 covers the lens 4 , the rotating shaft 21 can be flexibly disposed, for example, can be located above the lens 4 . (as shown in Figure 3), or below the lens 4 (as shown in Figure 13).

Optionally, referring to FIG. 2, FIG. 3 and FIG. 5 again, the self-cleaning assembly 300 further includes a driving member 5 for driving the rotating shaft 21 to drive the bracket 22 to rotate. The drive member 5 can be a motor. The driving member 5 is located on a side of the end cover 1 remote from the cleaning brush 2. The driving member 5 is electrically connected to the controller 301 and the power source 302.

Optionally, referring to FIG. 5 and FIG. 6, the lens 4 is fixed on the end cover 1 by assembly or the lens 4 is a part of the end cover 1.

For example:

In an embodiment, referring again to FIG. 3 and FIG. 5, the end cap 1 is provided with a through hole 11 , the lens 4 is a component independent of the end cap 1 , and the lens 4 is embedded in the The through hole 11 is covered at an opening of one end of the through hole 11 to be fixed to the end cover 1. For example, the lens 4 is embedded in the through hole 11, and the periphery of the lens 4 and the hole wall of the through hole 11 are bonded by an adhesive. Alternatively, the hole wall of the through hole 11 is provided with a limiting surface 111. The lens 4 is received in the through hole 11 , and the lens 4 abuts the limiting surface 111 . The limiting surface 111 and the periphery of the lens 4 are bonded by a double-sided tape or an adhesive. The limiting surface 111 may face the cleaning brush 2 to facilitate fixing the lens 4, or the limiting surface 111 may face away from the cleaning brush 2 to prevent the lens 4 from falling.

In another embodiment, referring again to Figures 3 and 6, the lens 4 is part of the end cap 1. The end cap 1 further includes a shielding area 12 surrounding the periphery of the lens 4. The lens 4 is made of a transparent material to allow light to pass through. The shielding area 12 is made of a light shielding material to achieve a shielding effect. The end cap 1 can be integrally formed by a buried molding process or a two-shot molding process.

Optionally, referring again to FIG. 3 and FIG. 5 , the lens 4 faces the mirror surface 41 of the cleaning brush 2 and the end cover 1 is flush with the outer surface 13 of the cleaning brush 2 . At this time, since the mirror surface 41 of the lens 4 is flush with the outer surface 13 of the end cap 1, a region where dirt is easily trapped is not formed at the periphery of the mirror surface 41, so that the cleaning brush 2 can The mirror surface 41 of the lens 4 is smoothly cleaned, and the cleaning efficiency is high and the cleaning effect is good.

It can be understood that the lens 4 has an acquisition area, and the lens 201 of the camera body 200 collects an image through the collection area. The collection area may cover the entire lens 4 or a partial area of the lens 4. The coverage ratio of the rotation range 20 of the cleaning brush 2 to the lens 4 is based on the collection area. The rotation range 20 of the cleaning brush 2 at least completely covers the collection area to ensure the quality of the image captured by the camera body 200.

Optionally, the mirror surface 41 of the lens 4 is covered with a hydrophobic coating, so that after the lens 4 is stained with dust, the dust can be smoothly drained by water (including but not limited to the condensation generated by the semiconductor refrigeration sheet 3). Water, rain, dew, etc. are carried away so that the mirror surface 41 of the lens 4 is kept relatively clean.

Optionally, referring again to FIG. 2, the camera 100 further includes a housing 6. The outer casing 6 is connected to the periphery of the end cap 1. The housing 6 and the end cover 1 together define an accommodating space 60. The camera body 200 is received in the accommodating space 60. The lens 201 is disposed in the accommodating space 60 adjacent to the end cap 1 to face the lens 4.

Optionally, referring to FIG. 2 to FIG. 10, the semiconductor refrigerating sheet 3 may be fixed on the end cover 1 or fixed on the cleaning brush 2, or located at the end cover 1 away from the One side of the cleaning brush 2 (for example, fixed to the outer casing 6). When the semiconductor refrigerating sheet 3 is fixed to the outer casing 6, it may be received in the accommodating space 60 or outside the accommodating space 60. When the semiconductor refrigerating sheet 3 generates the condensed water at any of the above positions, the condensed water may directly or indirectly contact the cleaning brush 2 or flow through the rotating range 20 of the cleaning brush 2 or flow through the lens. 4. The cleaning brush 2 is caused to carry the condensed water to clean the lens 4.

in particular:

In the first embodiment, referring again to FIG. 2, FIG. 3 and FIG. 5, the end cover 1 is provided with a receiving groove 14. The semiconductor refrigerating sheet 3 is housed in the receiving groove 14 . The receiving groove 14 is located within the rotation range 20 of the cleaning brush 2 . The cold end 31 of the semiconductor refrigerating sheet 3 is disposed adjacent to the outer surface 13 of the end cap 1, and the hot end 32 of the semiconductor refrigerating sheet 3 is disposed away from the outer surface 13 of the end cap 1. When the cold end 31 of the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the vicinity of the cold end 31 of the semiconductor refrigerating sheet 3, that is, at a region of the end cap 1 close to the semiconductor refrigerating sheet 3. The condensed water is formed. Since the receiving groove 14 is located within the rotation range 20 of the cleaning brush 2, the condensed water can be formed in the rotation range 20 of the cleaning brush 2, so that when the cleaning brush 2 is rotated, it is carried. The condensed water, the cleaning brush 2 cleans the lens 4 with water.

In the present embodiment, the condensed water is first cooled by the semiconductor refrigerating sheet 3, and after the condensed water flows through the rotation range 20 of the cleaning brush 2, the cleaning brush 2 is started to rotate, thereby making the cleaning The brush 2 carries the condensed water to clean the lens 4 as it rotates.

In the second embodiment, referring again to FIG. 2, FIG. 3 and FIG. 5, the end cover 1 is provided with a receiving groove 14. The semiconductor refrigerating sheet 3 is housed in the receiving groove 14 . The receiving groove 14 is vertically above the lens 4 such that the condensed water passes through the lens 4 under the force of gravity. The cold end 31 of the semiconductor refrigerating sheet 3 is disposed adjacent to the outer surface 13 of the end cap 1, and the hot end 32 of the semiconductor refrigerating sheet 3 is disposed away from the outer surface 13 of the end cap 1. When the cold end 31 of the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the vicinity of the cold end 31 of the semiconductor refrigerating sheet 3, that is, at a region of the end cap 1 close to the semiconductor refrigerating sheet 3. The condensed water is formed. Since the receiving groove 14 is located vertically above the lens 4, the condensed water can be formed vertically above the lens 4, so that the condensed water passes through the lens 4 under the force of gravity, When the cleaning brush 2 is rotated through the lens 4, the cleaning brush 2 can carry the condensed water to achieve water cleaning.

In the present embodiment, the condensed water is first cooled by the semiconductor refrigerating sheet 3, and the condensed water passes through the lens 4, and after the mirror surface 41 of the lens 4 is wetted, the cleaning brush 2 is started to rotate, thereby The cleaning brush 2 is caused to carry the condensed water to clean the lens 4 while rotating.

It can be understood that, in the above first embodiment, the receiving groove 14 can be disposed away from the vertical upper side of the lens 4. In the second embodiment described above, the receiving groove 14 can be disposed away from the rotation range 20 of the cleaning brush 2. In one embodiment, the receiving groove 14 is located both vertically above the lens 4 and within the range of rotation 20 of the cleaning brush 2.

In the first embodiment and/or the second embodiment, the bottom wall of the receiving groove 14 away from the outer surface 13 of the end cover 1 is provided with a communication hole 15 for allowing The power supply line of the semiconductor refrigerating sheet 3 passes. The semiconductor refrigerating sheet 3 housed in the housing groove 14 is electrically connected to the camera body 200 via the power source line.

In the first embodiment and/or the second embodiment described above, the cold end 31 of the semiconductor refrigerating sheet 3 has a condensation surface 311 away from the hot end 32 of the semiconductor refrigerating sheet 3, the condensation surface 311 and The outer surface 13 of the end cap 1 facing the cleaning brush 2 is flush. Since the condensation surface 311 is flush with the outer surface 13 of the end cap 1, the condensed water generated on the condensation surface 311 can smoothly flow from the condensation surface 311 to the outer surface of the end cap 1. 13 is applied to the mirror surface 41 of the lens 4 such that the mirror surface 41 of the lens 4 has sufficient condensed water to ensure the cleaning efficiency and cleaning effect of the self-cleaning assembly 300.

In the above first embodiment and/or the second embodiment, the waterproof wall 16 is filled between the groove wall of the receiving groove 14 and the semiconductor refrigerating sheet 3 to achieve a waterproof seal. Wherein, the waterproof gel 16 can completely wrap the semiconductor refrigeration sheet 3 to protect the semiconductor refrigeration sheet 3. Of course, the thickness of the portion of the waterproof gel 16 covering the cold end 31 of the semiconductor refrigerating sheet 3 is thinner than the thickness of other portions of the waterproof gel 16 to ensure the cooling effect of the cold end 31 of the semiconductor refrigerating sheet 3. The cold end 31 of the semiconductor refrigerating sheet 3 may also not be covered by the waterproof gel 16 to enhance the condensation effect.

In the third embodiment, referring to FIG. 7 and FIG. 8, the semiconductor refrigerating sheet 3 is fixed to the cleaning brush 2. The cold end 31 of the semiconductor refrigerating sheet 3 is disposed away from the cleaning brush 2 with respect to the hot end 32 of the semiconductor refrigerating sheet 3. When the cold end 31 of the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the vicinity of the cold end 31 of the semiconductor refrigerating sheet 3, that is, at a region of the cleaning brush 2 close to the semiconductor refrigerating sheet 3. The condensed water is formed. At this time, when the brush head 23 of the cleaning brush 2 is made of a water absorbing material, the condensed water can be quickly absorbed by the brush head 23, so that the cleaning brush 2 can carry the condensed water to clean the Lens 4. When the brush head 23 of the cleaning brush 2 is made of other hydrophilic materials, the condensed water can also penetrate into the brush head 23, so that the cleaning brush 2 can be cleaned with water.

In the present embodiment, the condensed water is first cooled by the semiconductor refrigerating sheet 3, and the condensed water is absorbed by the brush head 23 or penetrates into the brush head 23, and the cleaning brush 2 is activated to rotate. The cleaning brush 2 is caused to carry the condensed water to clean the lens 4 while rotating.

It can be understood that the cleaning brush 2 has an initial position when it is not rotated. As shown in Fig. 7, the solid line shows the initial position, and the broken line shows the other position after the rotation. The semiconductor refrigerating sheet 3 is fixed at an upper position of the cleaning brush 2 so that the condensed water is better absorbed by the brush head 23 or infiltrated into the brush head 23 by gravity. As shown in Figs. 7 and 8, the semiconductor refrigerating sheet 3 is disposed on the upper portion of the cleaning brush 2, and the brush head 23 of the cleaning brush 2 is made of a water absorbing material. When the lens 4 needs to be cleaned, the semiconductor refrigerating sheet 3 is energized, the semiconductor refrigerating sheet 3 condenses water vapor to generate the condensed water, the condensed water flows into the water absorbing material, and then the cleaning brush 2 is started to rotate and clean. The lens 4. Wherein, the condensed water generated by the semiconductor refrigerating sheet 3 is first absorbed or penetrated into the brush head 23 by the brush head 23, and then the brush head 23 directly carries the condensed water to clean the lens 4 Therefore, the rotating shaft 21 of the cleaning brush 2 may be located above the lens 4 (as shown in FIG. 7 ), below (as shown in FIG. 13 ) or other orientations, and the initial position of the cleaning brush 2 may also be Located above, below or in other orientations of the lens 4, the range of rotation 20 of the cleaning brush 2 covers the lens 4.

The hot end 32 of the semiconductor refrigerating sheet 3 may be fixed to the holder 22 of the cleaning brush 2 by a bonding method or the like. The bracket 22 has a connecting surface away from the brush head 23, and the connecting surface has a flat area with a large area to facilitate attachment of the hot end 32 of the semiconductor refrigerating sheet 3.

In one embodiment, the initial position of the cleaning brush 2 is located vertically above the lens 4 such that the condensed water passes the lens 4 under the force of gravity. When the cold end 31 of the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the vicinity of the cold end 31 of the semiconductor refrigerating sheet 3, that is, at a region of the cleaning brush 2 close to the semiconductor refrigerating sheet 3. The condensed water is formed. Since the initial position of the cleaning brush 2 is vertically above the lens 4, the semiconductor refrigerating sheet 3 is cooled when the cleaning brush 2 is in the initial position, so that the condensation can be formed vertically above the lens 4. Water, so that the condensed water passes through the lens 4 under the force of gravity, and when the cleaning brush 2 rotates through the lens 4, the cleaning brush 2 can carry the condensed water, thereby achieving water cleaning . Moreover, when the brush head 23 of the cleaning brush 2 is made of a water absorbing material or a hydrophilic material, the condensed water can also be sucked into the brush head 23 or penetrate the brush head 23 at the same time, so that the cleaning brush 2 The effect of cleaning the lens 4 with water is better.

In the embodiment, the condensed water is first cooled by the semiconductor refrigerating sheet 3, and the condensed water passes through the lens 4. After the mirror surface 41 of the lens 4 is wetted, the cleaning brush 2 is started to rotate, thereby The cleaning brush 2 is caused to carry the condensed water to clean the lens 4 while rotating. It can be understood that since the condensed water generated by the semiconductor refrigerating sheet 3 flows through the lens 4 first, the mirror surface 41 of the lens 4 is wetted, and then the rotating cleaning brush 2 passes through the lens 4. Contacting the condensed water to achieve water cleaning, so the rotating shaft 21 of the cleaning brush 2 is located above the lens 4 so that the initial position of the cleaning brush 2 can be located vertically of the lens 4 Above, the condensed water is condensed above the lens 4.

In the fourth embodiment, referring to FIG. 9 and FIG. 10 together, the self-cleaning assembly 300 further includes a water tank 7 and a water pipe 8. The semiconductor refrigeration sheet 3 is housed in the water tank 7 to form the condensed water in the water tank 7. The water tank 7 is located on a side of the end cover 1 away from the cleaning brush 2. The inlet end 81 of the water pipe 8 communicates with the water tank 7, and the outlet end 82 of the water pipe 8 is fixed to the end cover 1. The outlet end 82 of the water tube 8 is located within the range of rotation 20 of the cleaning brush 2. When the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the water tank 7. After the water tank 7 collects enough of the condensed water, the water pipe 8 can be turned on when the lens 4 needs to be cleaned, so that the condensed water flows out. Since the outlet end 82 of the water pipe 8 is located within the rotation range 20 of the cleaning brush 2, the condensed water can flow to the rotation range 20 of the cleaning brush 2, so that when the cleaning brush 2 is rotated, Carrying the condensed water to achieve clean water.

In the fifth embodiment, referring to FIG. 9 and FIG. 10 together, the self-cleaning assembly 300 further includes a water tank 7 and a water pipe 8. The semiconductor refrigeration sheet 3 is housed in the water tank 7 to form the condensed water in the water tank 7. The water tank 7 is located on a side of the end cover 1 away from the cleaning brush 2. The inlet end 81 of the water pipe 8 communicates with the water tank 7. An outlet end 82 of the water tube 8 is secured to the end cap 1 and vertically above the lens 4 such that the condensed water passes through the lens 4 under the force of gravity. When the semiconductor refrigerating sheet 3 is cooled, the condensed water is formed in the water tank 7. After the water tank 7 collects enough of the condensed water, the water pipe 8 can be turned on when the lens 4 needs to be cleaned, so that the condensed water flows out. Since the outlet end 82 of the water pipe 8 is vertically above the lens 4, the condensed water passes through the lens 4 under the force of gravity, and the cleaning is performed as the cleaning brush 2 rotates past the lens 4. The brush 2 can carry the condensed water to achieve water cleaning.

It will be appreciated that in the fourth embodiment described above, the outlet end 82 of the water tube 8 may be offset from the vertical upper side of the lens 4. In the fifth embodiment described above, the outlet end 82 of the water pipe 8 can be disposed offset from the rotation range 20 of the cleaning brush 2. In one embodiment, the outlet end 82 of the water tube 8 is located both vertically above the lens 4 and within the range of rotation 20 of the cleaning brush 2.

In the fourth embodiment and/or the fifth embodiment, the semiconductor refrigerating sheet 3 may be cooled to generate the condensed water when the lens 4 needs to be cleaned, or may be in a refrigerating state for a long time to make the water tank 7 Collect enough condensed water to start cleaning the lens 4 at any time, and the emergency response is fast. When the lens 4 needs to be cleaned, the water pipe 8 is turned on to allow the condensed water to flow out, and the cleaning brush 2 is cleaned with water.

In the fourth embodiment and/or the fifth embodiment, referring to FIG. 2 again, the water tank 7 can be housed in the accommodating space 60 to improve concealment, so that the camera 100 has a relatively clean and tidy manner. Appearance. At this time, the water tank 7 is fixed to the inner side of the outer casing 6. Of course, in other embodiments, the water tank 7 may also be fixed to the outer side wall of the outer casing 6 to collect a portion of natural water (eg, rain, dew, etc.).

In the fourth embodiment and/or the fifth embodiment, as shown in FIG. 10, an on-off valve 83 may be provided at the middle or at least one end of the water pipe 8 to control the conduction of the water pipe 8 and Disconnected state.

Referring to FIG. 1 to FIG. 12 together, the embodiment of the present application further provides a self-cleaning method. The self-cleaning method cleans the lens 4 using the self-cleaning assembly 300 of any of the above embodiments to enable the camera 100 to achieve long-term operation and better image quality. The self-cleaning assembly 300 includes an end cap 1, a cleaning brush 2, and a semiconductor refrigerating sheet 3. The end cap 1 is provided with a lens 4. The cleaning brush 2 is rotatably coupled to the end cap 1.

The self-cleaning method includes:

Step 01: The semiconductor refrigerating sheet 3 is cooled to form condensed water.

Step 02: Driving the cleaning brush 2 to rotate, so that the cleaning brush 2 carries the condensed water to clean the lens 4.

In this embodiment, the self-cleaning method is capable of cooling the semiconductor chilled sheet 3 from the production of the condensed water when the lens 4 needs to be cleaned, and then driving the cleaning brush 2 to clean the lens with water. Thus, self-cleaning is achieved efficiently, and the cleaning effect with water cleaning is good, and the lens 4 can be prevented from being worn.

It can be understood that the triggering condition of the step 01 may be: automatic triggering when there is dirt on the lens 4, or timing triggering, or manual triggering. Specifically, it can be judged whether there is dirt on the lens 4 by image signal processing, and when there is dirt on the lens 4, step 01 is automatically triggered. The timing trigger program can be set to automatically trigger step 01 after a certain period of interval. Step 01 can be temporarily manually triggered in other environments where the lens 4 needs to be cleaned (e.g., fog, etc.). The above three trigger conditions may be selected one, or a combination of a plurality of them may be selected. For example, it is cleaned once a week by default, and combined with image signal processing to determine in real time whether there is any stain on the lens that affects the image quality, and when it exists, the cleaning is triggered immediately.

Optionally, the process of cooling the semiconductor refrigerating sheet 3 to form condensed water (ie, step 01) includes:

Step 011: Calculate the dew point temperature based on the air temperature and the air humidity. The dew point temperature is the temperature at which water vapor in the air is condensed into water. The semiconductor refrigerating sheet 3 is provided with a temperature sensor 304 and a humidity sensor 305 for temperature and humidity detection of air. Of course, temperature sensor 304 and humidity sensor 305 can also be disposed on other components of self-cleaning assembly 300 (eg, end cap 1 etc.). As shown in FIG. 4, the temperature sensor 304 and the humidity sensor 305 are electrically connected to the controller 301. The controller 301 performs an operation based on the data detected by the temperature sensor 304 and the humidity sensor 305.

Step 012: The cold end 31 of the semiconductor refrigerating sheet 3 continues for a first time at the first temperature to lower the air temperature to the dew point temperature. When the air temperature is lowered to the dew point temperature, water vapor in the air begins to condense to form the condensed water.

Step 013: The cold end 31 of the semiconductor refrigerating sheet 3 continues for a second time at a second temperature to form condensed water, and the second temperature is higher than or equal to the first temperature. The cold end 31 of the semiconductor refrigerating sheet 3 is continuously cooled, thereby forming a sufficient amount of the condensed water to ensure the cleaning effect of the self-cleaning method. It can be understood that the second duration is calculated according to the preset water consumption. When the amount of water of the condensed water is greater than or equal to the predetermined amount of water, the semiconductor refrigerating sheet 31 stops cooling. The preset water consumption amount is related to factors such as the use environment of the camera 100 (for example, air dust density, etc.) and the area of the lens 4. The preset water consumption may be preset in the self-cleaning component 300, for example, preset in the controller 301, or the self-cleaning component 300 further includes a memory for storing the preset water consumption, etc. parameter.

In this embodiment, since the air temperature has decreased to the dew point temperature, the second temperature may be equal to the first temperature to form sufficient condensed water as soon as possible, and the second temperature may also be higher than The first temperature, thereby reducing the energy consumption of the semiconductor refrigerating sheet 3 while continuously forming the condensed water. In the embodiment of the present application, the first duration and the second duration are not limited, and the first duration and the second duration may be flexibly set according to the temperature and humidity of the air and the requirement of the cleaning water.

For example:

The dew point temperature of the air can be calculated by the formula (1): Td = b / [a / log (e / 6.11) - 1].

In formula (1), Td is the dew point temperature of air, in degrees Celsius (°C); e is the water vapor pressure of air, in units of hectopascals (hpa); a, b are fixed parameters, for water surface, a=7.5, b =237.3.

Among them, the formula (2) of the water vapor pressure of air is e = f × Es.

In formula (2), f is the relative humidity of air, in percent (%); Es is the saturated vapor pressure of air in units of hectopascals (hpa).

Es is calculated according to the formula (3): Es = E0 × 10 [a × t / (b + t)].

In formula (3), E0 is the saturated water vapor pressure at an air temperature of 0 degrees, taking E0 = 6.11 hectopascals (hpa); t is the air temperature in units of degrees Celsius (°C).

Based on the above three formulas, after the temperature and relative humidity of the current air are obtained by the temperature and humidity sensor 305, the dew point temperature of the current air can be calculated. For example, when the air temperature is 25 ° C and the relative humidity is 50%, the dew point temperature is calculated as follows:

Es = 6.11 × 10 [7.5 × 25 / (237.3 + 25)] = 31.7hpa;

e=0.5×31.7=15.85hpa;

Td = 237.3 / [7.5 / log (15.85 / 6.11) - 1] = 13.86 ° C.

That is, when the temperature of the air in the vicinity of the semiconductor refrigerating sheet 3 is lowered to 13.86 ° C, condensation will occur.

The refrigeration coefficient of the semiconductor refrigerating sheet 3 is ε, which represents the cooling energy generated per unit of power consumption, expressed in percentage (%), which is related to the physical properties, resistance, current, etc. of the cooling sheet, when a specific After the cooling chip and the supply voltage, the coefficient is a fixed value. The power consumption of the semiconductor refrigerating sheet 3 is P, and the specific heat of the water vapor is C = 2.1 × 103 joules per kilogram Celsius (J / (kg · ° C)), and the mass of water required to clean the lens 201 is m, water vapor. The temperature before cooling is T1, the temperature after cooling is the dew point temperature is Td, and the cooling time is t. According to the conservation of energy, the cooling time t is calculated according to formula (4): P × ε × t = C × m × (T1-Td). Assume that the cooling chip consumes 5 watts (W), the cooling coefficient is 0.5, the water required to clean the lens 201 is 1g, the air temperature is 25 degrees, and the relative humidity is 50%. According to formula (4), the dew point temperature is calculated to 13.86. The time t required to produce 1 g of condensed water at ° C was 9.4 seconds.

Optionally, before the calculating the dew point temperature (ie, step 011), the process of cooling the semiconductor refrigerating sheet 3 to form condensed water (ie, step 01) further includes:

Step 001: Detect the air temperature.

Step 002: When the air temperature is lower than the first threshold, the semiconductor refrigerating sheet 3 continues to heat for a third time period to raise the air temperature to a second threshold, the second threshold being greater than the first threshold .

Step 003: Detecting air humidity.

In this embodiment, when it is detected that the air temperature is lower than the first threshold, the ambient air temperature is very low, and it is difficult to directly obtain the condensed water through the semiconductor refrigeration sheet 3, so in step 002 First, by heating, the air temperature is raised to the second threshold (for example, 25 degrees Celsius), and at this time, the semiconductor refrigerating sheet 3 can be smoothly condensed to obtain the condensed water.

It can be understood that step 003 can be performed simultaneously with step 001 to save detection time. When the air temperature is greater than or equal to the first threshold, the dew point temperature may be calculated according to the detected air temperature and air humidity. If the semiconductor refrigerating sheet 3 still needs to be heated to raise the temperature of the air to the second threshold, the air humidity needs to be detected again, so that the dew point temperature can obtain an accurate value according to the updated and more accurate data. .

The foregoing is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application. It should be covered by the scope of protection of this application. Therefore, the scope of protection of the present application should be determined by the scope of the claims.

Claims

A self-cleaning assembly is applied to a camera, wherein the self-cleaning assembly comprises an end cover, a cleaning brush and a semiconductor refrigeration sheet, the end cover is provided with a lens, and the cleaning brush is rotatably connected to the end cover. The semiconductor refrigerating sheet is used to generate condensed water, and the condensed water is carried through the lens to rotate the lens during the rotation of the cleaning brush.
The self-cleaning assembly according to claim 1, wherein the cleaning brush comprises a rotating shaft, a bracket and a brush head, and the bracket is rotatably connected to the end cover by the rotating shaft, and the brush head is fixed to the bracket To the side of the end cap, the head is made of a water absorbing material.
A self-cleaning assembly according to claim 1 or 2, wherein the mirror facing the mirror and the end cap are flush with the outer surface of the cleaning brush.
The self-cleaning assembly according to any one of claims 1 to 3, wherein the end cover is provided with a receiving groove, the semiconductor cooling sheet is received in the receiving groove, and the receiving groove is located in the cleaning Within the range of rotation of the brush.
The self-cleaning assembly according to any one of claims 1 to 3, wherein the end cover is provided with a receiving groove, the semiconductor refrigeration sheet is received in the receiving groove, and the receiving groove is located in the lens Vertically above, the condensed water passes through the lens under the force of gravity.
A self-cleaning assembly according to claim 4 or 5, wherein the cold end of the semiconductor refrigerating sheet has a condensing surface away from the hot end of the semiconductor refrigerating sheet, the condensing surface and the orientation of the end cap The outer surface of the cleaning brush is flush.
The self-cleaning assembly according to any one of claims 1 to 3, wherein said semiconductor refrigerating sheet is fixed to said cleaning brush, and said cold end of said semiconductor refrigerating sheet is opposite to said hot end of said semiconductor refrigerating sheet Keep away from the cleaning brush settings.
The self-cleaning assembly of claim 7 wherein the initial position of the cleaning brush is vertically above the lens such that the condensed water passes the lens under the force of gravity.
The self-cleaning assembly according to any one of claims 1 to 3, further comprising a water tank and a water pipe, the semiconductor refrigeration sheet being housed in the water tank to form a space in the water tank Condensed water, the water tank is located on a side of the end cover away from the cleaning brush, an inlet end of the water pipe communicates with the water tank, an outlet end of the water pipe is fixed on the end cover and is located in the cleaning Within the range of rotation of the brush.
The self-cleaning assembly according to any one of claims 1 to 3, further comprising a water tank and a water pipe, the semiconductor refrigeration sheet being housed in the water tank to form a space in the water tank Condensed water, the water tank is located on a side of the end cover away from the cleaning brush, an inlet end of the water pipe is connected to the water tank, and an outlet end of the water pipe is fixed on the end cover and located in the lens Vertically above, the condensed water passes through the lens under the force of gravity.
A camera comprising: a camera body and the self-cleaning assembly according to any one of claims 1 to 10, wherein the camera body is located on a side of the end cover away from the cleaning brush, the camera body The lens is placed against the lens.
A self-cleaning method, characterized in that a lens is cleaned using a self-cleaning assembly, the self-cleaning assembly comprising an end cap, a cleaning brush and a semiconductor refrigeration sheet, the end cap being provided with a lens, the cleaning brush being rotatably connected to the end The cover, the self-cleaning method includes:

Cooling the semiconductor refrigeration sheet to form condensed water; and

The cleaning brush is driven to rotate such that the cleaning brush carries the condensed water to clean the lens.
The self-cleaning method according to claim 12, wherein the process of cooling the semiconductor refrigerating sheet to form condensed water comprises:

Calculate the dew point temperature based on air temperature and air humidity;

The cold end of the semiconductor refrigerating sheet continues for a first time at a first temperature to reduce an air temperature to the dew point temperature;

The cold end of the semiconductor refrigerating sheet continues for a second time at a second temperature to form condensed water, the second temperature being higher than or equal to the first temperature.
The self-cleaning method according to claim 13, wherein the process of cooling the semiconductor refrigerating sheet to form condensed water before calculating the dew point temperature further comprises:

Detecting air temperature;

When the air temperature is lower than the first threshold, the semiconductor cooling sheet continues to heat for a third time period to raise the air temperature to a second threshold, the second threshold being greater than the first threshold;

Check the air humidity.