JP3127962B2 - Monitoring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus such as an industrial television camera or a camera for confirming the rear of an automobile, and more particularly to a monitoring apparatus for preventing image quality deterioration due to adhesion of water droplets.

[0002]

2. Description of the Related Art For example, a monitoring device such as a vehicle-mounted rear-viewing camera is exposed to an external environment, and therefore needs to have a structure capable of obtaining a good image under various weather conditions. FIG. 3 shows a conventional example of a rear view camera having such a structure, in which a camera-side power supply circuit 31 and a camera circuit 32 connected to the power supply circuit 31 are provided in a housing 30 containing the camera. A circuit 33 and a temperature control circuit 34 are provided, and the power supply circuit 31 on the camera side is connected to a vehicle power supply 35 such as a battery. Among these circuits, the camera circuit 32 sends a signal to a monitor television 36 installed in the automobile to display an image on the monitor television 36. Reference numeral 40 denotes a cover glass provided in the housing 30 of the camera. The cover glass 40 is attached to a window (not shown) formed in the housing 30 so as to face the camera, and seals the window, thereby preventing rainwater from entering and protecting the camera. are doing. The cover glass 40 may be clouded (condensed) by water droplets,
Freezing of water droplets is not preferable because the image quality is reduced. Therefore, the surface of the cover glass 40 is coated with the conductive film 41.
, And the coating 41 is connected to the electrode 42, and the electrode 42 is connected to the heating circuit 33. With this configuration, the electric power from the vehicle power supply 35 is supplied from the power supply circuit 31 and the heat generation circuit 33 on the camera side to the conductive coating 41.
The conductive film 41 generates heat, and water droplets can be evaporated from the cover glass 40. In addition,
The amount of heat generated is controlled by attaching a thermistor 43 to the conductive film 41 and detecting the temperature, and outputting the detected temperature to the detected temperature control circuit 34 to control the heat generation circuit 33.

[0003]

In the above-described monitoring device such as a camera for confirming the rearward direction, a power source is a battery mounted on a vehicle or the like, and its capacity is limited. Undesirable consumption is high.
Further, a heat generating circuit 33 for generating heat from the conductive film 41.
In addition, a circuit such as a temperature control circuit 34 for controlling the heating circuit 33 is required, and the circuit configuration is complicated. Further, a process of covering the cover glass 40 with the conductive film 41 is necessary,
There was a problem that it became expensive in itself.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a monitoring device that maintains good visibility without requiring power consumption.

[0005]

In order to achieve the above object, a monitoring device according to the present invention has a built-in monitoring device, a housing having a window portion facing the monitoring device, and a window portion sealed. A transparent cover attached to the housing so that the transparent cover is attached to the housing in contact with the transparent cover inside the housing, and a heat radiating portion of the semiconductor device for power supply of the monitoring device is attached in a contact state. And a heat transfer plate, wherein the semiconductor device is an IC voltage regulator and is provided one on each side of the window.

[0006]

[0007] The transparent cover seals the window of the housing,
By preventing intrusion of dust and the like, the monitoring device facing the window is protected. A semiconductor device supplies power to a monitoring device, and has a characteristic of generating heat when the power is supplied. Heat generated from the heat radiating portion of the semiconductor device is transmitted to the transparent cover via the heat transfer plate, and increases the temperature of the transparent cover. As a result, dew condensation on the transparent cover and the like are prevented, and clear and favorable monitoring of the field of view is performed. On the other hand, heat radiation from the heat radiation portion of the semiconductor device is reliably performed.

Further, in the present invention, since the semiconductor devices are provided one on each side of the window, that is, since the window is located between the two semiconductor devices, the region facing the window of the transparent cover is provided. The heat of the semiconductor device can be efficiently transferred to the semiconductor device, thereby preventing dew condensation over the entire surface of the region, and making the field of view of the monitoring device extremely good. Furthermore, since the transparent cover is attached to the housing by the heat transfer plate, a dedicated attaching member for attaching the transparent cover to the housing is not required, and the number of components can be reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a camera for confirming the rear of an automobile will be described below with reference to FIGS. Reference numeral 1 shown in both figures denotes a housing attached to an appropriate position at the rear of the vehicle body, and a window 2
Are formed. Reference numeral 3 denotes a lens barrel including a lens, aperture blades, and the like, and constitutes a part of a camera as a monitoring device that captures an image behind the vehicle. This lens barrel 3
Is integrated with the circuit board 4, and is mounted in the housing 1 so that the lens faces the window 2 in this state. A transparent cover 5 such as a transparent glass plate or a transparent resin plate is adhered to the inner surface of the housing 1 around the window portion 2 so that the window portion 2 is sealed, and water, dust and the like are sealed. It does not enter the housing 1. In this case, an O-ring 6 is interposed between the peripheral portion of the window 2 and the transparent cover 5 to ensure the housing 1 is securely sealed. A heat transfer plate 7 is in close contact with the rear surface of the transparent cover 5, and the IC regulator 8
Is attached.

As the heat transfer plate 7, a metal press plate whose central portion corresponding to the window portion 2 is punched is used, and a pressing plate for attaching the transparent cover 5 to the housing 1 by abutting against the back surface of the transparent cover 5. Acts as. Heat transfer plate 7 in the illustrated example
Is fixed in the housing 1 by a screw 9, and a boss portion 1 a for screwing the screw 9 is formed in the housing 1. The fixing of the heat transfer plate 7 may be performed by other means such as bonding and hooking.

The IC regulators 8 are provided on both left and right sides of the heat transfer plate 7. The IC regulator 8 is connected to a battery (not shown) mounted on the vehicle, transforms the battery power to a specified voltage, and supplies it to a camera (not shown). In the illustrated example, a three-terminal regulator is used as the IC regulator 8, but any other IC may be used as long as the IC supplies a specified voltage to the camera. The power supply IC 8 has a characteristic of generating heat when power is supplied. The IC regulator 8 is mounted so as to be in contact with the heat transfer plate 7. The IC package 8a includes a bracket plate for heat dissipation (a heat dissipation plate of a three-terminal regulator).
0 is integrally attached, and the bracket plate 1
0 is fixed by screws 11 in a state of surface contact with the heat transfer plate 7.

In the above configuration, when power is supplied from the power supply IC 8 to the camera to check the rear, the IC regulator 8 generates heat. This heat is transmitted to the heat transfer plate 7 and further transmitted to the transparent cover 5 in contact with the heat transfer plate 7 to increase the temperature of the transparent cover 5. Therefore, even if water droplets adhere to the transparent cover 5 or form water, they are evaporated, so that fogging due to these is eliminated. As a result, a clear image can be captured with a good field of view, and the rearward confirmation can be reliably performed. In this embodiment, since the characteristic that the IC regulator 8 generates heat is used, it is not necessary to consume power as a countermeasure against such dew condensation, and power can be saved. Further, a circuit for generating heat is not required, and the cost of covering the transparent cover 5 with a conductive film is eliminated. Further, since the effective area of the IC regulator 8 as a heat sink is increased and heat can be radiated well, destruction, malfunction, and runaway due to heat are eliminated, and the IC regulator 8 can be operated stably.

In the above embodiment, the number of components is reduced by using the heat transfer plate as a holding plate for the transparent cover, but a structure used only for heat transfer may be used. Also, the number of IC regulators can be changed as appropriate. Furthermore, the present invention is not limited to a camera for confirming backwards,
The present invention can be similarly applied to a monitoring device such as a door camera or another CCD camera, a photoelectric switch, or the like.

[0014]

As described above, according to the present invention, the heat dissipating portion of the power supply semiconductor device of the monitoring device comes into contact with the transparent cover via the heat transfer plate, and the heat dissipating portion has good heat dissipation. Since the prevention of condensation and the like on the transparent cover can be performed at the same time, good monitoring can be performed without requiring power dedicated to the prevention of condensation.

In the configuration in which the transparent cover is attached to the housing by the heat transfer plate, the number of parts is reduced, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a monitoring device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the monitoring device according to one embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a conventional monitoring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Housing 2 ... Window part 3 ... Lens barrel 5 ... Transparent cover 7 ... Heat transfer plate 8 ... IC regulator

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-148040 (JP, A) JP-A-54-141689 (JP, A)

Claims (1)

(57) [Claims] 1. A housing having a built-in monitoring device and having a window facing the monitoring device; a transparent cover attached to the housing so as to seal the window; A heat transfer plate to which the transparent cover is attached to the housing in contact with the transparent cover, and a heat radiating portion of a semiconductor device for power supply of the monitoring device is attached in a contact state. Is an IC voltage regulator and is provided on both sides of the window one by one.