Automatic windscreen wiper system based on capacitive sensing

Abstract

The utility model discloses an automatic windscreen wiper system based on capacitive sensing, which comprises a front windshield, a first side edge and a second side edge which are oppositely arranged, a first electrode is arranged on the first side edge of the front windshield, a second electrode is arranged on the second side edge of the front windshield, and the first electrode is electrically connected with the second electrode. A rainfall sensing capacitor is formed between the first electrode and the second electrode; the windscreen wiper device is used for sweeping rainwater in front of the front windshield; the control device is electrically connected with the windscreen wiper device and the first electrode and the second electrode of the front windshield. The automatic windscreen wiper system is based on capacitive sensing, is not interfered by ambient light, and is high in integration level and small in size.

Description

Technical Field

[0001] The utility model relates to an intelligent automobile component, in particular to an automatic windshield wiper system. Background Art

[0002] The car's automatic wiper system automatically detects rainfall intensity through a rain sensor, and then automatically controls the start of the wiper motor according to the rainfall intensity to drive the wiper blades to swing, thereby sweeping away rain in front of the windshield to keep the windshield dry and clean, enhancing the driver's visibility, and ensuring that the driver can concentrate on driving, eliminating potential accidents and increasing driving comfort.

[0003] Currently, the most widely used type of rain sensor is the photoelectric rain sensor. This sensor contains an infrared emitting diode (LED), which emits infrared light. The infrared light passes through the windshield and hits the windshield's outer surface. When raindrops or water fall onto the glass, the refractive index changes, preventing total reflection of the light. Instead, it is partially reflected depending on the size of the water droplets. The receiving tube then receives only a partial signal, which is then used to calculate the rainfall amount based on the percentage ratio. This information can be used to control the wiper motor's movement, thereby controlling the wiper's operating speed and duration. When the glass is dry, the light is fully reflected and, after passing through the lens system, is received by the receiving device as parallel light, achieving a maximum output of 100%.

[0004] However, photoelectric rain sensors are susceptible to interference from ambient light, resulting in weak photoelectric conversion signals that are easily overwhelmed by noise. For example, in rainy weather, the sensor receives both reflected light and ambient light, making it prone to misjudging the rainfall. Utility Model Content

[0005] In order to solve the above-mentioned deficiencies in the prior art, the utility model provides an automatic wiper system which is based on capacitive sensing, is not affected by ambient light, and has high integration and small size.

[0006] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0007] An automatic windshield wiper system based on capacitive sensing, comprising:

[0008] A front windshield having a first side and a second side opposite to each other, a first electrode being provided on the first side of the front windshield, a second electrode being provided on the second side of the front windshield, and a rain sensing capacitor being formed between the first electrode and the second electrode;

[0009] a wiper device, for sweeping away rainwater in front of the front windshield;

[0010] The control device is electrically connected to the wiper device and the first electrode and the second electrode of the front windshield respectively.

[0011] Furthermore, the first electrode and the second electrode extend along a first side edge and a second side edge of the front windshield, respectively.

[0012] Furthermore, the first electrode and the second electrode are parallel to each other.

[0013] Furthermore, the first electrode and the second electrode are light-shielding electrodes.

[0014] Furthermore, the first electrode and the second electrode are black conductive ink.

[0015] Furthermore, the front windshield includes a first glass substrate and a second glass substrate, and the first glass substrate and the second glass substrate are relatively bonded and fixed by a PVB film; the first electrode and the second electrode are arranged on the side surface of the first glass substrate facing the second glass substrate, or the first electrode and the second electrode are arranged on the side surface of the second glass substrate facing the first glass substrate.

[0016] Furthermore, the front windshield further includes a first circuit board and a second circuit board, and the first electrode and the second electrode of the front windshield are connected to the control device through the first circuit board and the second circuit board respectively.

[0017] Furthermore, the front windshield further includes a common circuit board, and the first electrode and the second electrode of the front windshield are connected to the control device via the common circuit board.

[0018] Furthermore, the wiper device includes a wiper motor and at least one wiper blade, the wiper blade is arranged in front of the front windshield, the output end of the wiper motor is transmission-connected to the wiper blade, and the control end of the wiper motor is electrically connected to the control device.

[0019] Furthermore, the control device includes a controller, a constant voltage source and a current collector, the controller is connected to control the constant voltage source, the current collector and the wiper device respectively, and the constant voltage source is electrically connected to the first electrode and the second electrode of the front windshield through the current collector.

[0020] The present invention has the following beneficial effects: the automatic wiper system of the present invention respectively arranges the first electrode and the second electrode on the first side and the second side of the front windshield to form a rain sensing capacitor for sensing the amount of rain, and then uses the control device to control the wiper device according to the rain intensity sensed by the rain sensing capacitor, such as controlling the start and stop and speed of the wiper device; the rain sensing capacitor is not affected by ambient light and is integrated inside the front windshield, with the advantages of high integration and small size. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural diagram of the automatic wiper system provided by the utility model.

[0022] Figure 2 This is a schematic diagram of the laminated structure of the front windshield in the automatic wiper system provided by the utility model.

[0023] Figure 3 This is a schematic diagram of the laminated structure of the front windshield in another automatic wiper system provided by the present invention.

[0024] Figure 4 This is a schematic diagram of the exploded structure of the front windshield in the automatic wiper system provided by the utility model.

[0025] Figure 5 This is a schematic diagram of the exploded structure of the front windshield in another automatic wiper system provided by the present invention. DETAILED DESCRIPTION

[0026] The present invention is described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0027] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first," "second," or "third" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0029] In this utility model, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," "fixed," and "set" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0030] Example 1

[0031] like Figure 1 As shown, an automatic wiper system based on capacitive sensing includes:

[0032] A front windshield 1 has a first side and a second side opposite to each other, a first electrode 11 is provided on the first side of the front windshield 1, and a second electrode 12 is provided on the second side of the front windshield 1, and a rain sensing capacitor is formed between the first electrode 11 and the second electrode 12;

[0033] a wiper device 2, for sweeping away rainwater in front of the front windshield 1;

[0034] The control device 3 is electrically connected to the wiper device 2 and the first electrode 11 and the second electrode 12 of the front windshield 1 respectively.

[0035] The automatic wiper system of the present invention respectively arranges the first electrode 11 and the second electrode 12 on the first side and the second side of the front windshield 1 to form a rain sensing capacitor for sensing the amount of rain, and then uses the control device 3 to control the wiper device 2 according to the rain intensity sensed by the rain sensing capacitor, such as controlling the start and stop and speed of the wiper device 2; the rain sensing capacitor is not affected by ambient light and is integrated inside the front windshield 1, with the advantages of high integration and small size.

[0036] During sensing, the control device 3 applies a constant voltage across the rain sensing capacitor formed by the first electrode 11 and the second electrode 12, so that the rain sensing capacitor is fully charged. When the voltage is constant, the charge of the rain sensing capacitor is proportional to its capacitance value, and the capacitance value of the rain sensing capacitor is proportional to the dielectric constant of the medium between the first electrode 11 and the second electrode 12. When there is no rain on the front windshield 1, the medium between the first electrode 11 and the second electrode 12 is only glass. When there is rain on the front windshield 1, The medium between the first electrode 11 and the second electrode 12 becomes glass + rainwater. The change in the dielectric constant causes the capacitance value of the rain sensing capacitor to change, and the change in the capacitance value causes the charge of the rain sensing capacitor to change. In order to achieve a new charge balance, the rain sensing capacitor forms a charging and discharging current to the outside. The greater the rainfall, the faster the charging and discharging current formed by the rain sensing capacitor changes. The control device 3 can judge the amount of rainfall according to the speed of change of the charging and discharging current of the rain sensing capacitor, and then control the start and stop and speed of the wiper device 2.

[0037] The first electrode 11 and the second electrode 12 extend along the first side and the second side of the front windshield 1 respectively, so that the first electrode 11 and the second electrode 12 are respectively distributed along the first side and the second side of the front windshield 1 as much as possible, so that the sensing range of the rain sensing capacitor covers the entire front windshield 1.

[0038] Preferably, the first electrode 11 and the second electrode 12 are parallel to each other, so that the capacitance value of the rain sensing capacitor at each position along the side direction of the front windshield 1 is the same.

[0039] In some examples, the first electrode 11 and the second electrode 12 are light-shielding electrodes.

[0040] Light-shielding electrodes are used as the first electrode 11 and the second electrode 12 , so that the first electrode 11 and the second electrode 12 have not only a conductive function but also a light-shielding function. In addition to forming the rain sensing capacitor, they also form the frame appearance of the front windshield 1 .

[0041] In this embodiment, the first electrode 11 and the second electrode 12 are made of black conductive ink, and the thickness thereof is between 1 μm and 3 μm.

[0042] The black conductive ink is formed by uniformly mixing conductive particles into a black ink base material. The conductive particles may include, but are not limited to, silver powder, aluminum flakes, copper powder, or graphite powder. The black conductive ink is applied to the front windshield 1 via a screen printing process to form the first and second electrodes 11 and 12.

[0043] Specifically, such as Figure 2 and 3 As shown, the front windshield 1 includes a first glass substrate 13 and a second glass substrate 14, which are relatively bonded and fixed to each other via a PVB film 15; the first electrode 11 and the second electrode 12 are arranged on a side surface of the first glass substrate 13 facing the second glass substrate 14, or the first electrode 11 and the second electrode 12 are arranged on a side surface of the second glass substrate 14 facing the first glass substrate 13.

[0044] In some examples, as shown in Figure 4, the front windshield 1 further includes a first circuit board 16 and a second circuit board 17, and the first electrode 11 and the second electrode 12 of the front windshield 1 are connected to the control device 3 through the first circuit board 16 and the second circuit board 17 respectively.

[0045] Preferably, the first circuit board 16 and the second circuit board 17 are flexible circuit boards.

[0046] In some examples, such as Figure 5 As shown, the front windshield 1 further includes a common circuit board 18 , and the first electrode 11 and the second electrode 12 of the front windshield 1 are connected to the control device 3 through the common circuit board 18 .

[0047] Preferably, the common circuit board is a flexible circuit board 18 .

[0048] In some examples, such as Figure 4 and 5 As shown, the front windshield 1 also includes a first wiring 19 and a second wiring 110, one end of the first wiring 19 is connected to the first electrode 11, and the other end extends to the third side of the front windshield 1 to be connected to the first circuit board 16 or the common circuit board 18; one end of the second wiring 110 is connected to the second electrode 12, and the other end extends to the third side of the front windshield 1 to be connected to the second circuit board 17 or the common circuit board 18; the third side is located between the first side and the second side.

[0049] In order to prevent the charges on the first wiring 19 and the second wiring 110 from affecting the voltage between the first electrode 11 and the second electrode 12, preferably, the first electrode 11 and the second electrode 12 are arranged on the surface of one of the first glass substrate 13 and the second glass substrate 14, and the first wiring 19 and the second wiring 110 are arranged on the surface of the other of the first glass substrate 13 and the second glass substrate 14, and the PVB film 15 is provided with a first conductive hole 151 and a second conductive hole 152 for connecting the first electrode 11 and the first conductive electrode, and the second electrode 12 and the second wiring 110, respectively.

[0050] like Figure 1 As shown, the wiper device 2 includes a wiper motor 21 and at least one wiper blade 22. The wiper blade 22 is arranged in front of the front windshield 1. The output end of the wiper motor 21 is transmission-connected to the wiper blade 22, and the control end of the wiper motor 21 is electrically connected to the control device 3.

[0051] The transmission mechanism between the wiper motor 21 and the wiper blade 22 can be, but is not limited to, a connecting rod swing mechanism, a screw rod sliding mechanism, or the like, or the wiper motor 21 is a swing motor. The wiper device 2 is an existing device, so its structure is not described in detail here.

[0052] The control device 3 includes a controller, a constant voltage source and a current collector. The controller is connected to control the constant voltage source, the current collector and the wiper device 2 respectively. The constant voltage source is electrically connected to the first electrode 11 and the second electrode 12 of the front windshield 1 through the current collector.

[0053] The constant voltage source is used to provide a constant voltage to the first electrode 11 and the second electrode 12 for charging and discharging; the current collector is used to collect the charging and discharging current between the constant voltage source and the first electrode 11 and the second electrode 12, and provide the collected current data to the controller; the controller is used to control the start, stop and speed of the wiper device 2 according to the current data collected by the current collector.

[0054] In this embodiment, the controller may be, but is not limited to, a CPU (central processing unit), an MCU (microcontroller or single chip microcomputer), an FPGA (programmable gate array), an NPU (neural network processor), etc. The current collector is an ADC collector.

[0055] In some examples, the control device 3 also includes a vehicle-mounted mainboard (not shown in the figure), and the controller, constant voltage source and current collector are all mounted on the vehicle-mounted mainboard; the vehicle-mounted mainboard is provided with a connector or electrical interface for electrically connecting the wiper motor 21 of the wiper device 2 and the first electrode 11 and the second electrode 12 of the front windshield 1.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention rather than to limit them. Although the embodiments of the present invention are described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solutions of the embodiments of the present invention can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An automatic wiper system based on capacitive sensing, characterized in that: include: A front windshield having a first side and a second side opposite to each other, a first electrode being provided on the first side of the front windshield, a second electrode being provided on the second side of the front windshield, and a rain sensing capacitor being formed between the first electrode and the second electrode; a wiper device, for sweeping away rainwater in front of the front windshield; The control device is electrically connected to the wiper device and the first electrode and the second electrode of the front windshield respectively.

2. The automatic wiper system according to claim 1, characterized in that: The first electrode and the second electrode extend along a first side edge and a second side edge of the front windshield, respectively.

3. The automatic wiper system according to claim 1 or 2, characterized in that: The first electrode and the second electrode are parallel to each other.

4. The automatic wiper system according to claim 1, characterized in that: The first electrode and the second electrode are light-shielding electrodes.

5. The automatic wiper system according to claim 4, characterized in that: The first electrode and the second electrode are made of black conductive ink.

6. The automatic wiper system according to claim 1, characterized in that: The front windshield includes a first glass substrate and a second glass substrate, which are relatively bonded and fixed to each other via a PVB film; the first electrode and the second electrode are arranged on a surface of the first glass substrate facing the second glass substrate, or the first electrode and the second electrode are arranged on a surface of the second glass substrate facing the first glass substrate.

7. The automatic wiper system according to claim 1 or 6, characterized in that: The front windshield further includes a first circuit board and a second circuit board, and the first electrode and the second electrode of the front windshield are connected to the control device through the first circuit board and the second circuit board respectively.

8. The automatic wiper system according to claim 1 or 6, characterized in that: The front windshield further includes a common circuit board, and the first electrode and the second electrode of the front windshield are connected to the control device via the common circuit board.

9. The automatic wiper system according to claim 1, characterized in that: The wiper device includes a wiper motor and at least one wiper blade. The wiper blade is arranged in front of the front windshield. The output end of the wiper motor is transmission-connected to the wiper blade. The control end of the wiper motor is electrically connected to the control device.

10. The automatic wiper system according to claim 1, characterized in that: The control device includes a controller, a constant voltage source and a current collector. The controller is connected to control the constant voltage source, the current collector and the wiper device respectively. The constant voltage source is electrically connected to the first electrode and the second electrode of the front windshield through the current collector.

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