JP7411418B2 - Heater unit and its applied products - Google Patents

Description

The present invention provides a heater unit for removing dew condensation, ice, frost, and water droplets adhering to, for example, a camera unit, windshield, radar unit, etc. in a vehicle, and also for preventing fogging, dew condensation, ice, and frost from adhering to the camera unit, windshield, radar unit, etc.; , relates to a windshield device equipped with this heater unit.

A vehicle windshield device is attached to the cabin side of a windshield and is used to detect the presence or absence of other vehicles or obstacles in front of the vehicle. A vehicle windshield device includes a bracket fixed to the windshield, a camera unit or a radar unit supported by the bracket, and a light-shielding hood that suppresses external light such as sunlight from entering the camera unit. When the humidity inside the vehicle is high or the temperature outside the vehicle is low, fog, condensation, frost, ice, etc. adhere to the windshield, so the vehicle windshield device heats the light shielding hood. The heater unit is located behind the blackout hood. The heat emitted from this heater unit melts, evaporates, and removes fog, dew condensation, frost, ice, etc. adhering to the windshield facing the light shielding hood. Thereby, the photograph taken by the camera unit becomes clear. Moreover, accurate detection is possible without attenuation of the radar from the radar unit (see Patent Documents 1, 2, etc.).

Patent No. 6583651 Patent No. 6589726

Particularly in the electrical components of automobiles, there is a demand for safety functions against excessive temperature rises due to unexpected short circuits and overcurrents. This is no exception for heater units in vehicle windshield devices; for example, in Patent Documents 1 and 2 mentioned above, a fuse is provided, and when an excessive temperature rise occurs due to this, the power supply to the heater unit is cut off. The structure is such that On the other hand, there are so many electrical parts in cars these days, and some cars, such as electric cars and hybrid cars, use electricity as power, so it is extremely important to save power in individual parts. This is an important issue. Furthermore, when it comes to vehicle windshield devices, if the device itself becomes large, it obstructs the driver's view, so there is a demand for it to be as small as possible, and various components such as camera units and radar units are placed there. For this reason, the heater unit is also required to have a space-saving design.

The present invention was made in order to solve the problems of the prior art, and its purpose is to provide a heater unit that not only has sufficient safety functions but also contributes to power saving and space saving. An object of the present invention is to provide a vehicle windshield device equipped with the same.

In order to achieve the above object, a heater unit according to the present invention includes a foil-like conductor, a planar base material on which the conductor is disposed, and a temperature control device that controls energization to the conductor. The conductor is made of a single conductor foil, and is composed of a wide lead part and a narrow heater part, and the heater part has a main heater part and an auxiliary heater part. , the temperature control device is operated by heating of the auxiliary heater section.
Further, it is conceivable that the main heater section includes at least a first heater section and a second heater section, and the auxiliary heater section is located between the first heater section and the second heater section. .
Further, it is conceivable that the temperature control device is connected in series with both the main heater section and the auxiliary heater section.
A vehicle windshield device according to the present invention includes the above heater unit, a bracket attached to the windshield of a vehicle, a sensor unit housed in the bracket, and a light shielding hood housed in the bracket, and includes the above-mentioned heater unit. A heater unit is attached to the bracket, the sensor unit, or the light shielding hood.

According to the present invention, since the energization to the conductor is controlled by the temperature control device, the energization is reliably cut off when the temperature rises to ensure safety, and the energization and cutoff can be switched at a predetermined temperature. Total power consumption can be reduced. Furthermore, since the temperature control device is heated in a pseudo manner by the auxiliary heater section, the temperature control device can be installed at a free location separate from the main heater section. That is, the temperature control device can be designed in a position where it does not interfere with the arrangement of other components, contributing to space saving.

1 is a plan view showing the configuration of a heater unit according to an embodiment of the present invention. 1 is an enlarged cross-sectional view schematically showing a main part of a heater unit according to an embodiment of the present invention. FIG. 2 is a plan view showing a partial configuration of a heater unit according to an embodiment of the present invention. FIG. 2 is a circuit diagram of a heater unit according to an embodiment of the present invention. 3 is a graph showing temperature measurement data according to an embodiment of the present invention. 1 is a sectional view showing an outline of a vehicle windshield device according to the present invention. FIG. 3 is a circuit diagram showing another embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the drawings.

First, as shown in FIGS. 1 to 3, there is a base material 7 made of a polyamideimide film having a thickness of 28 μm. The base material used in the present invention is a film made of conventionally known polymeric materials such as synthetic resins, and includes, for example, polyamide-imide film, PET film (polyester film), polyimide film, polyphenylene sulfide film, etc. Preferably used.

On this base material 7, a conductor 1 having a thickness of 30 μm obtained by etching a stainless steel (SUS304) foil is formed. As the conductor 1, in addition to stainless steel, metals such as copper, aluminum, nickel chromium, etc. are preferably used. Further, a conductive resin or the like may be used. These are patterned, for example, by etching, punching, etc., and are obtained in the form of a single sheet of foil. Further, the conductor pattern may be formed by a method such as vapor deposition or coating. The shaded portion shown in FIG. 3 becomes the conductor 1. The conductor 1 consists of a lead part 3, which has a low resistance value due to its wide width and does not substantially generate heat, and a heater part 5, which has a narrow width and has a high resistance value and contributes to heat generation. Become. The heater section 5 has a main heater section 10 and an auxiliary heater section 13. Further, in the present embodiment, the main heater section 10 includes the first heater section 11 and the second heater section 12, and the auxiliary heater section 13 is arranged between the first heater section 11 and the second heater section 12. It is configured to be located. Note that the resistance values of the first heater section 11 and the second heater section 12 are each set to 17.9Ω so as to be (13.6V-3.72W). Further, the resistance value of the auxiliary heater section 13 is set to 6.4Ω so as to be (13.6V-0.66W).

Moreover, as shown in FIG. 2, an adhesive layer 9 for adhering to other members may be formed on the base material 7. In this embodiment, the surface of the base material 7 on which the conductor 1 is formed is the surface that comes into contact with the heated portion, and the adhesive layer 15 made of adhesive tape is formed on this surface. Further, in order to increase the efficiency of heat conduction to the heated portion, it is also possible to install a heat insulating sheet 21 made of foamed resin or the like on the opposite side to the surface in contact with the heated portion. In this case, it is also possible to use a heat insulating sheet 21 that is a combination of a plurality of materials having different properties such as heat insulating properties, heat resistance, shock absorption properties, and appearance. In this embodiment, the base material 7 and the heat insulating sheet 21 are attached with an adhesive layer 16 made of adhesive tape.

The conductor 1 and base material 7 obtained as described above have a pattern shape as shown in FIG. 3. Here, two ends of the lead portion 3 of the conductor 1 are exposed, one end is connected to the lead wire 25, and the other end is connected to another lead wire via the thermostat 23 as a temperature control device. 26. Temperature control devices include temperature sensing elements such as thermistors and protection circuits such as thermal fuses. Note that the connection between the lead part 3 and the lead wire 25, the connection between the lead part 3 and the thermostat 23, and the connection between the thermostat 23 and the lead wire 26 are covered with a heat shrink tube 27 for the purpose of waterproofing and mechanical protection. It is possible that Further, the thermostat 23 will be installed at a position where the auxiliary heater section 13 is present. In this way, the heater unit 31 as shown in FIG. 1 is obtained.

Regarding the heater unit 31 having such a configuration, the circuit configuration and the operation of the temperature control device will be explained with reference to the circuit diagram shown in FIG. As shown in FIG. 4, a thermostat 23, which is a temperature control device, is connected to the power supply VCC, and a first heater section 11, an auxiliary heater section 13, and a second heater section 12 are connected in series, and are connected to the ground GND. . Furthermore, the amount of heat generated and the degree of cooling of the auxiliary heater section 13 and the operating temperature of the thermostat 23 are set so that the first heater section 11 and the second heater section 12 generate heat at appropriate temperatures. Therefore, by heating the thermostat 23 with the auxiliary heater 13, the temperatures of the first heater section 11 and the second heater section 12 are controlled in a pseudo manner. As a result, when the temperatures of the first heater section 11 and the second heater section 12 reach a predetermined value, the thermostat 23 is turned off, and the entire heater unit 31 is de-energized. Further, the temperature of the entire heater unit 31 decreases due to the interruption of energization, but when the temperature of the thermostat 23 falls to a predetermined value, the thermostat 23 is turned on again and the energization is resumed. By repeating this process, the temperature of the heater unit 31 is maintained within a predetermined range.

Such a heater unit 31 can be installed inside a vehicle windshield device. An example of a vehicle windshield device will be described with reference to FIG. The right side in FIG. 6 is the front of the vehicle, and the vehicle windshield device attached to the windshield 57 includes a bracket 51, a light shielding hood 53, and a camera unit 55 as a sensor unit. The bracket 51 is a resin member having a bowl shape, and houses the light shielding hood 53 and the camera unit 55. Adhesive is applied to the peripheral edge of the bracket 51, and the bracket 51 is attached to the cabin side of the windshield 57. Note that the windshield 57 is generally sometimes referred to as a windshield, a side glass, or a rear glass. The camera unit 55 is fixedly held by a resin member formed within the bracket. At this time, the light receiving section of the camera unit 55 is directed toward the windshield 57, and no other member is interposed between the light receiving section of the camera unit 55 and the windshield 57. The light shielding hood 53 is a plate-shaped black resin member that defines the range of light that the light receiving section of the camera unit 55 receives. In addition, the surface of the light-shielding hood 53 is coated with non-woven fabric, or has a pear-like finish, a textured finish, a cut-off finish, etc., so that light is scattered, and external light from outside the light receiving area is scattered. It is designed to suppress the incidence of light. Although not illustrated, this embodiment corresponds to a compound-eye system including two camera units 55. A first heater section is installed on one camera unit side, a second heater section is installed on the other camera unit side, and an auxiliary heater section and a thermostat are arranged between these two camera units. Note that the camera unit 55 may also be a radar unit.

When the humidity in the vehicle interior is high or the temperature outside the vehicle is low, fogging, dew condensation, frost, ice, etc. may adhere to the windshield 57. This cloudiness, dew condensation, frost, ice, etc. scatters light, which may impede clear photography by the camera unit 55. This also applies when a radar unit is used instead of a camera unit. Therefore, the heater unit 31 is attached to the back side of the light-shielding hood 53, and by heating the windshield 57 through the light-shielding hood 53 with the heat emitted from the main heater part 10 of the heater unit 31, fogging, dew condensation, frost, and ice can be prevented. will be removed. Further, the air inside the bracket 51 is heated by the heat from the heater unit 31, and the humidity inside the bracket 51 is thereby reduced, thereby removing dew condensation.

The heater unit 31 installed in the windshield device as described above was actually energized and the temperature was measured. The center part of the first heater part (A), the center part of the second heater part (B), the center part of the sub-heater (C), the top of the light shielding hood 53 (D), and the inner surface of the windshield 57 (E) A thermocouple was attached as a measurement point, and current was applied at an applied voltage of 13.5V at an initial ambient temperature of 22.9° C., and changes in temperature over time at each measurement point (A) to (E) were measured. A graph showing the results of temperature measurement is shown in FIG. As shown in FIG. 5, it was confirmed that the heater unit 31 according to this embodiment provided stable heating.

Note that the present invention is not limited to the above embodiments. In the above embodiment, the main heater section 10 consists of the first heater section 11 and the second heater section 12, but it may also consist of only the first heater section, and further, the main heater section 10 may consist of the first heater section 11 and the second heater section 12. It may also be added to the heater section.

Further, in the above embodiment, the first heater section 11, the auxiliary heater section 13, the second heater section 12, and the thermostat 23 are connected in series, but the present invention is not limited thereto. For example, the first heater section 11, the auxiliary heater section 13, and the second heater section 12 may be arranged in parallel. Furthermore, as shown in FIG. 7, a circuit configuration may be considered in which the auxiliary heater section 13 continues to be energized even after the thermostat 23 is turned off. In this case, the thermostat 23 will not be turned on again, so the control is such that only the second heater section 12 continues to generate heat.

Further, the positions of the first heater section 11, the second heater section 12, and the auxiliary heater section 13 can be freely set. It is preferable that the auxiliary heater section 13 is located between the first heater section 11 and the second heater section 12 as in the above embodiment. Here, the position between the first heater section 11 and the second heater section 12 includes both a circuit position and a mounting position, and it is sufficient if at least one of them is satisfied.

In particular, when the first heater section 11, the second heater section 12, and the auxiliary heater section 13 are arranged close to each other, there is a possibility that they are mutually affected by heat generation. It is preferable that the distance to the heater section 13 and the distance between the second heater section 12 and the auxiliary heater section 13 are substantially the same. As a result, even when heat from the auxiliary heater section 13 is transmitted to the first heater section 11 and the second heater section 12, it is transmitted to the first heater section 11 and the second heater section 12 in the same way, and the heat from the auxiliary heater section 13 is transmitted to the first heater section 11 and the second heater section 12. It is possible to prevent a difference in temperature between the heater section 11 and the second heater section 12. Furthermore, the pattern of the conductor 1 on the first heater section 11 side and the pattern of the conductor 1 on the second heater section 12 side are symmetrical with respect to a line between the first heater section 11 and the second heater section 12. It is preferable that the

In the embodiment described above, the heater unit 31 is attached to the back side of the light-shielding hood 53, but the heater unit 31 may be attached at another location. For example, it can be installed in various places such as the front side of the light shielding hood 53, the inside of the bracket 51, the outside of the bracket 51, the periphery of the camera unit (sensor unit) 55, the cabin side of the windshield 57, etc. It can also be installed on.

Further, as the sensor unit, in addition to the camera unit 55 as in the above embodiment, a radar unit, a laser lidar unit, an ultrasonic sensor unit, etc. can be considered. The present invention can also be applied to camera units and radar units that are mounted and exposed outside the vehicle. In this case, it is also conceivable to attach the heater unit around the light receiving section of the camera unit or to the radome that covers the radar unit.

As described in detail above, according to the present invention, it is possible to obtain a heater unit that has sufficient safety functions and can also contribute to power saving and space saving. Such a heater unit can be suitably used as a heat source for, for example, household heating equipment, automobile interior heating equipment, industrial heating equipment, various snow removal/ice melting equipment, antifogging equipment, cooking appliances, and the like. In addition, it can be used not only as a conduction heat transfer heater that is used in contact with the object to be heated, but also as a radiation heat transfer heater that is installed at a distance from the object to be heated. .

1 Conductor 3 Lead part 5 Heater part 7 Base material 10 Main heater part 11 First heater part 12 Second heater part 13 Auxiliary heater part 23 Thermostat (temperature control device)
31 Heater unit 51 Bracket 53 Light shielding hood 55 Camera unit (sensor unit)
57 Windshield

Claims (6)

Consisting of a foil-like conductor, a planar base material on which the conductor is disposed, and a temperature control device that controls energization to the conductor,
The conductor is made of a single conductor foil, and is composed of a wide lead part and a narrow heater part, and the heater part has a main heater part and an auxiliary heater part,
A heater unit in which the temperature control device operates by heating the auxiliary heater section and controls energization to the main heater section. The heater according to claim 1, wherein the main heater section includes at least a first heater section and a second heater section, and the auxiliary heater section is located between the first heater section and the second heater section. unit. The heater unit according to claim 2, wherein a distance between the first heater section and the auxiliary heater section and a distance between the second heater section and the auxiliary heater section are substantially the same. The heater unit according to claim 1, wherein the temperature control device is connected in series with both the main heater section and the auxiliary heater section. The heater unit according to claim 1, wherein the main heater section and the auxiliary heater section are arranged via the lead section. The heater unit according to any one of claims 1 to 5 , a bracket attached to a windshield of a vehicle, a sensor unit housed in the bracket, and a light shielding hood housed in the bracket,
A vehicle windshield device, wherein the heater unit is attached to the bracket, the sensor unit, or the light shielding hood.

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