JP2005056462A - Internal structure of onboard device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the internal structure of an onboard device having no possibility of staining a pickup part for reading a medium by dusts in air. <P>SOLUTION: In the case 10 of a car navigation device 1, a media reading housing part 20 which is a roughly sealed space formed by a high heat absorbing shield plate 21 is disposed. A media reading mechanism 3 is arranged in the media reading mechanism housing part 20. When a fan 5 is driven, external air is sucked into the case 10 to cool each part. The external air sucked by the fan 5 does not caused to flow into the media reading mechanism housing part 20. Heat generated from the media reading mechanism 3 is transmitted through the high heat absorbing shield plate 21 forming the media reading mechanism housing part 20 to the air flowing in the case 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal structure of an in-vehicle device that reads a signal from at least a medium on which an image is recorded.
[0002]
[Prior art]
For example, a car navigation device is known as an in-vehicle device that reads a signal from a medium on which an image or the like is recorded. In a so-called 1DIN car navigation apparatus, media storing map information and the like are inserted into and removed from the front of the apparatus. Therefore, an opening for inserting / removing media is provided on the front surface of the car navigation device (see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-36153
[Problems to be solved by the invention]
Among the parts mounted on the circuit board built in the car navigation device, there are parts that generate a large amount of heat. Therefore, external heat is sucked from the air intake port by a fan provided in the housing to cool these heat generating components. However, in the conventional car navigation apparatus, outside air is sucked not only from the air inlet but also from the opening for inserting / removing the medium, so that there is a possibility that the pickup portion for reading the medium is contaminated by dust in the air.
[0005]
The present invention provides an internal structure of an in-vehicle device in which a pickup portion that reads media is not contaminated by dust in the air.
[0006]
(1) The internal structure of the in-vehicle device according to the invention of claim 1 is arranged in a housing, a shielding plate for providing a substantially sealed space in the housing, and a substantially sealed space provided by the shielding plate. A reading mechanism for reading at least an image or audio signal from the inserted medium, a circuit board disposed outside the substantially sealed space provided by the shielding plate and disposed in the housing, and a circuit board And a heat dissipating means for dissipating heat generated from the outside of the housing.
(2) The invention of claim 2 is the internal structure of the in-vehicle device according to claim 1, wherein the housing is provided with an air intake port for taking in air from the outside, and a shield plate provided from the outside. An air discharge port for discharging air that has passed through the inside of the housing outside the sealed space is further provided.
(3) The invention of claim 3 is the internal structure of the in-vehicle device according to claim 2, further comprising a fan for sucking air outside the housing from the air suction port and discharging it from the air discharge port. The housing is installed in the vehicle so that at least the front surface is exposed in the vehicle interior, the media is inserted into and removed from the front surface of the housing, and the air inlet is provided on the front surface of the housing.
(4) According to a fourth aspect of the present invention, in the internal structure of the in-vehicle device according to the first to third aspects, the shielding plate is made of a member that has been subjected to a process for increasing the emissivity.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
---overall structure---
With reference to FIGS. 1 and 2, an embodiment in which the internal structure of the in-vehicle device of the present invention is applied to a car navigation device will be described. FIG. 1A is a front view of the car navigation apparatus 1. FIG. 1B is a plan view of the car navigation device 1, and FIG. 1C is a diagram showing an internal configuration of the car navigation device 1 as viewed from the side. Inside the car navigation device 1, a medium reading mechanism 3 having a pickup 3a for reading information recorded on the medium 2, and a substrate 4 on which a circuit for processing a signal read by the pickup 3a is mounted, A fan 5 for ventilating air is provided inside the car navigation apparatus 1. A case 10 that houses each component device of the car navigation device 1 is a substantially rectangular parallelepiped casing, and a media insertion port 11 and a front intake port 12 are provided on the front surface thereof. An upper air inlet 13 is provided on the upper surface of the case 10. An exhaust port 14 is provided on the back surface of the case 10, and the fan 5 is disposed in the vicinity of the exhaust port 14 inside the case 10.
[0008]
Inside the case 10, the storage unit 20 of the substantially rectangular parallelepiped media reading mechanism 3 is formed as a substantially sealed structure. 2A is a perspective view showing the relationship between the case 10 and the media reading mechanism storage unit 20 when viewed from the II-II plane of FIG. 1B, and FIG. 2B is the II-II plane. FIG. Two surfaces, the front surface and the bottom surface of the media reading mechanism storage unit 20, are formed by the front surface and the bottom surface of the case 10. The other four surfaces of the media reading mechanism storage unit 20 are formed by a highly heat-absorbing shielding plate 21. The high endothermic shielding plate 21 is obtained by increasing the absorption rate of radiant heat, that is, emissivity, by subjecting the steel plate to surface treatment. A portion where the highly heat-absorbing shielding plate 21 and the front surface and the bottom surface of the case 10 are in contact with each other is not particularly coated with a sealant or the like. Therefore, although it is slight, a gap is generated in a portion where the highly heat-absorbing shielding plate 21 and the front surface and the bottom surface of the case 10 abut.
[0009]
The media insertion slot 11 is open in a range corresponding to the front surface of the case 10 and the front surface of the media reading mechanism storage unit 20. In other words, the outside of the case 10 communicates with the space 100 inside the media reading mechanism storage unit 20 via the media insertion slot 11, but between the outside of the case 10 and the inside of the case 10 via the media insertion slot 11. Therefore, it does not communicate with the space 200 outside the media reading mechanism storage unit 20.
[0010]
The media reading mechanism 3 is disposed in the media reading mechanism storage unit 20. In addition to the pickup 3a described above, the media reading mechanism 3 includes a media driving unit 3b that drives the media, a pickup driving unit 3c that drives the pickup 3a, and media that controls these pickups 3a and the driving units 3b and 3c. And a reading mechanism control board 3d. The media reading mechanism control board 3d and the board 4 are connected via a flexible cable 6.
[0011]
As shown in FIGS. 1C and 2B, the substrate 4 is placed on the upper surface of the case 10 so as to maintain a predetermined distance from the media reading mechanism storage unit 20 in the space 200 above the media reading mechanism storage unit 20. It is supported. In the electronic circuit mounted on the substrate 4, various calculations for navigation are performed based on the map information read from the medium 2 and a signal from a GPS sensor (not shown). Based on the calculation result, reading control of the medium 2 is performed. Then, a signal such as an image or a sound read from the medium 2 is output to a monitor or a speaker (not shown). In order to perform such various processes, various electronic components such as an image and sound signal processing IC, an arithmetic and control IC, and an amplification IC are mounted on the substrate 4. Among these electronic components, there is also a component (hereinafter referred to as a heat generating component) 4a that generates a particularly large amount of heat. As shown in FIG. 1, the heat generating component 4 a is mounted on the upper surface of the substrate 4. The upper surface intake port 13 of the case 10 is provided so as to be positioned substantially directly above the heat generating component 4a.
[0012]
The car navigation device 1 described above may be mounted in the instrument panel of the vehicle so that the front surface is exposed in the vehicle interior, or may be installed in the vehicle interior or trunk.
[0013]
――― Air flow inside case 10 ―――
When the fan 5 is driven, air outside the case 10 is sucked from the front air inlet 12 and the upper air inlet 13 and introduced into the case 10. As shown in FIG. 1 (c), a part of the external air sucked from the front air inlet 12 flows between the upper surface of the substrate 4 and the case 10 (arrow 31), and the remaining air flows from the substrate 4. It flows through the space between the lower surface and the upper surface of the media reading mechanism storage unit 20 (arrow 32). External air sucked from the upper surface inlet 13 flows between the upper surface of the substrate 4 and the case 10 (arrow 33). The air sucked into the case 10 from the intake ports 12 and 13 in this way flows substantially parallel to the substrate 4 and is exhausted to the outside from the exhaust port 14 provided on the back surface of the case 10.
[0014]
As an opening of the case 10, there is a media insertion port 11 in addition to the intake ports 12 and 13 and the exhaust port 14 described above. However, as described above, the outside of the case 10 and the space 200 inside the case 10 and outside the media reading mechanism storage unit 20 are not communicated with each other via the media insertion opening 11. That is, when viewed from the position of the fan 5, the media insertion slot 11 is covered with the highly heat-absorbing shielding plate 21 of the media reading mechanism storage unit 20. As described above, there is a slight gap in the portion where the highly heat-absorbing shielding plate 21 and the front surface and bottom surface of the case 10 are in contact. , 13 is sufficiently larger than the ventilation resistance when external air is sucked. Therefore, outside air is hardly sucked into the inside (space 100) of the media reading mechanism storage unit 20 from the media insertion opening 11. For this reason, there is no possibility that the pickup 3a of the media reading mechanism 3 stored in the media reading mechanism storage unit 20 is contaminated by dust contained in the external air.
[0015]
――― Cooling of each part ――――
Since the heat generating component 4a is disposed immediately below the upper surface intake port 13, the heat generating component 4a is cooled by direct contact with external air sucked from the upper surface intake port 13. Other electronic components mounted on the substrate 4 also generate heat, but are cooled by air that flows substantially parallel to the substrate 4 on the upper and lower surfaces of the substrate 4.
[0016]
The media reading mechanism 3 also generates heat from the driving units 3b and 3c and the media reading mechanism control board 3d. The heat generated in each part of the media reading mechanism 3 is transferred from the media reading mechanism 3 to the highly heat-absorbing shielding plate 21 forming the media reading mechanism storage unit 20 by radiant heat transfer or convective heat transfer. The high endothermic shielding plate 21 heated by the heat generated by the media reading mechanism 3 is sucked by the fan 5 and cooled by the air flowing on the upper surface of the high endothermic shielding plate 21. As described above, since the heat generated from the media reading mechanism 3 can be released to the outside, the media reading mechanism 3 can be cooled.
[0017]
The internal structure of the vehicle-mounted device according to the embodiment described above has the following effects.
(1) The media reading mechanism 3 is stored in the media reading mechanism storage unit 20. The case 10 is provided with a front air inlet 12 and an upper air inlet 13. Therefore, even if the fan 5 is driven for cooling and the outside air is sucked into the case 10 (space 200), the air does not flow inside the medium reading mechanism storage unit 20 (space 100). Thereby, there is no possibility that the pickup unit 3a is soiled by dust in the air, and information can be read from the medium 2 stably.
(2) The media reading mechanism storage unit 20 was formed using the high endothermic shielding plate 21. As a result, the heat generated from the media reading mechanism 3 can be efficiently transmitted to the outside of the media reading mechanism storage unit 20, so that the media reading mechanism 3 can be sufficiently cooled.
(3) The front air inlet 12 is provided on the front surface of the case 10, the exhaust air outlet is provided on the back surface of the case 10, and the inside of the case 10 is ventilated by the fan 5. Thereby, since air flows smoothly inside case 10, each part can be cooled efficiently.
(4) The heat generating component 4a is mounted on the upper surface of the substrate 4, and the upper air inlet 13 is positioned on the upper surface of the heat generating component 4a. Thereby, a part with much calorific value can be cooled efficiently.
[0018]
In the above description, the media reading mechanism storage unit 20 is disposed below and the substrate 4 is disposed above in the housing, but the present invention is not limited to this. The media reading mechanism storage unit 20 may be disposed above and the substrate 4 may be disposed below, and the substrate 4 may be disposed above and below the media reading mechanism storage unit 20.
[0019]
In the above description, the front air inlet 12 is provided on the front surface of the case, and the fan 5 is provided in the vicinity of the back surface of the case 10. However, if the arrangement can efficiently cool the components inside the case 10, the above description will be given. It is not limited at all. In the above description, the car navigation device is described as an example of the in-vehicle device, but the present invention is not limited to this. For example, the present invention can be applied to an apparatus that optically reads information such as an image from a medium, such as a DVD playback apparatus for in-vehicle use.
[0020]
In the above description, it is assumed that the heat generated in the media reading mechanism 3 is transferred from the media reading mechanism 3 to the high endothermic shielding plate 21 forming the media reading mechanism storage unit 20 by radiant heat transfer or convective heat transfer. However, the present invention is not limited to this. A heat transfer member that connects the media reading mechanism 3 and the highly heat-absorbing shielding plate 21 may be provided so that heat generated in the media reading mechanism 3 by conduction heat transfer is transmitted to the highly-absorbing shielding plate 21. In addition, the present invention does not prevent any contrivance for improving the overall heat transfer coefficient from the media reading mechanism 3 to the air outside the media reading mechanism storage unit 20, for example, providing a heat radiating rib on the highly heat-absorbing shielding plate 21. Furthermore, the above-described embodiments and modifications may be combined.
[0021]
In the above embodiment and its modifications, the casing is the case 10, the shielding plate is the medium reading mechanism housing portion 20 formed by the highly heat-absorbing shielding plate 21, the circuit board is the substrate 4, and the air inlet port. Corresponds to the front air inlet 12 and the upper air inlet 13, and the air outlet corresponds to the air outlet 14. The heat dissipating means includes the fan 5, the front air inlet 12, the upper air inlet and the exhaust outlet 14. Furthermore, as long as the characteristic functions of the present invention are not impaired, the present invention is not limited to the device configuration in the above-described embodiment.
[0022]
【The invention's effect】
In the internal structure of the in-vehicle device according to the present invention, a space substantially sealed in the housing by the shielding plate is provided, and a reading mechanism for reading at least image or audio signals from the media is provided in this space. Thereby, since there is no possibility that the pickup portion that reads the medium is soiled by dust in the air, information can be read stably from the medium.
[Brief description of the drawings]
FIG. 1 is a diagram showing a car navigation device according to an embodiment, where (a) is a front view, (b) is a plan view, and (c) is a side view of the car navigation device 1. It is the figure which showed the internal structure.
2 is a diagram illustrating the inside of the car navigation device of FIG. 1, wherein (a) is the relationship between the case 10 and the media reading mechanism storage unit 20 when viewed from the II-II plane of FIG. 1 (b). (B) is sectional drawing in the II-II surface.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Car navigation apparatus 2 Media 3 Media reading mechanism 3a Pickup 4 Board | substrate 4a Heat-generating component 5 Fan 10 Case 11 Media insertion port 12 Front inlet 13 Upper surface inlet 14 Exhaust port 20 Media reading mechanism storage part 21 High heat absorption shield

Claims (4)

A housing,
A shielding plate for providing a substantially sealed space in the housing;
A reading mechanism that is disposed in a substantially sealed space provided by the shielding plate and reads at least an image or audio signal from the inserted medium;
A circuit board disposed outside the substantially sealed space provided by the shielding plate and disposed in the housing;
An internal structure of an in-vehicle device, comprising: heat radiating means for radiating heat generated by the circuit board to the outside of the housing. In the internal structure of the in-vehicle device according to claim 1,
In the housing, an air intake port for taking air from the outside,
An internal structure of an in-vehicle device, further comprising an air discharge port that discharges air that has been taken in from outside and is outside a substantially sealed space provided by the shielding plate and has passed through the housing. The internal structure of the in-vehicle device according to claim 2,
A fan for sucking air outside the housing from the air inlet and discharging it from the air outlet;
The housing is installed in the vehicle so that at least the front surface is exposed in the vehicle interior,
The media is inserted and removed from the front surface of the housing,
An internal structure of an in-vehicle device, wherein the air suction port is provided on a front surface of the housing. In the internal structure of the in-vehicle device according to claims 1 to 3,
The internal structure of an in-vehicle device, wherein the shielding plate is made of a member that has been subjected to a process that increases emissivity.

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