CN112753057B

CN112753057B - Display device

Info

Publication number: CN112753057B
Application number: CN201980062595.4A
Authority: CN
Inventors: 桑原达也
Original assignee: Nippon Seiki Co Ltd
Current assignee: Nippon Seiki Co Ltd
Priority date: 2018-09-25
Filing date: 2019-09-12
Publication date: 2023-06-16
Anticipated expiration: 2039-09-12
Also published as: JP7355023B2; JPWO2020066647A1; CN112753057A; WO2020066647A1

Abstract

Provided is a display device which can easily provide a ventilation part and can perform good heat release. A display device comprises at least a display member (2) and a housing member (5) for housing the display member (2), wherein the housing member (5) has a heat-dissipating member (7) having heat conductivity, the heat-dissipating member (7) has ventilation holes (73, 74) for allowing air to pass therethrough, the ventilation holes (73, 74) have porous films (9) for preventing liquid from passing therethrough, the ventilation holes (73, 74) include a 1 st ventilation hole communicating with the outside, and a 2 nd ventilation hole (74) communicating with the 1 st ventilation hole (73) and with the inside, and the porous films (9) are provided between the 1 st ventilation hole (73) and the 2 nd ventilation hole (74).

Description

Display device

Technical Field

The present invention relates to a display device mounted on an automobile, for example, and more particularly to a display device having a heat dissipation structure.

Background

The conventional display device is disclosed in patent document 1, for example. The display device is composed of a display, a circuit substrate for driving the display, and a housing for accommodating the display and the circuit substrate, a heat radiation member is provided to cover an opening provided in the rear of the housing, a columnar extension forming portion is formed on the heat radiation member to be in contact with the display via the opening, and the extension forming portion is provided below the circuit substrate. Thus, a display device capable of satisfactorily dissipating heat is provided.

Prior art literature

Patent literature

Patent document 1: JP-A2005-338541

Disclosure of Invention

Problems to be solved by the invention

However, in particular, in the case of an instrument device in which antifogging property is required, when a heat radiating member is disposed on a housing, there is a problem that a space for a vent hole is limited, sufficient ventilation cannot be ensured, and water mist is generated on a display and the housing.

The present invention has been made in view of the above problems, and an important object thereof is to provide a display device in which a ventilation portion can be easily provided and which can perform excellent heat dissipation.

Means for solving the problems

The display device of the present invention includes at least a display member 2 and a housing member 5 for housing the display member 2, wherein the housing member 5 has a heat-conductive heat-dissipating member 7, and the heat-dissipating member 7 has

ventilation holes

73, 74 for allowing air to pass therethrough.

According to the embodiments of the present disclosure, a display device can be provided that can achieve a desired object, can easily provide a ventilation portion, and can perform good heat dissipation.

Drawings

Fig. 1 is a cross-sectional view showing embodiment 1 of a display device of the present disclosure;

fig. 2 is a perspective view showing the radiator according to the embodiment;

fig. 3 is a cross-sectional view showing embodiment 2 of the display device of the present disclosure.

Detailed Description

A case where an embodiment employing the display device of the present disclosure is applied to a display device mounted on a vehicle will be described below with reference to fig. 1 to 3.

Embodiment 1 of a display device of the present disclosure is described with reference to fig. 1 and 2. The display device includes: the liquid crystal display device includes a front-most transmissive casing 1, a liquid crystal display device (display member) 2 disposed behind the transmissive casing 1 and serving as a display, a middle casing 3 accommodating the liquid crystal display device 2, a circuit board (heat generating member) 4 disposed behind the middle casing 3, and a casing (casing member) 5 disposed behind the circuit board 4 so as to cover the back side thereof.

The transmissive cover 1 is made of light-shielding synthetic resin and has a substantially rectangular parallelepiped box shape with an opening on the back side. The transmissive casing 1 has a translucent synthetic resin plate 11 insert-molded on the front surface side. The display device enables the vehicle user to observe the liquid crystal display device 2 through the synthetic resin plate 11. The transmission case 1 is fitted to the case 5, and is fixed so that water or dust does not enter inside.

The liquid crystal display device 2 is called a liquid crystal module, and includes a liquid crystal display unit, a backlight device including an LED (Light Emission Diode: light emitting diode) and a transparent resin light guide plate, a liquid crystal control substrate, and the like. In addition, the LEDs are accompanied by heat generation. The reference numeral 21 denotes a metal shielding plate, which is a plate for protecting a circuit in the liquid crystal display device 2 from electromagnetic waves or the like, and is a heat radiation plate for radiating heat of a heat generating component such as a backlight device or the like incorporated in the liquid crystal display device 2.

The middle case 3 is made of synthetic resin, is a quadrangular frame body for accommodating the liquid crystal display device 2, and has a stepped portion 31 for fixing the liquid crystal display device 2 on its inner surface.

The circuit board 4 is a hard board whose base material is made of glass epoxy resin, and has a rectangular shape. In order to drive the liquid crystal display unit and the backlight device of the liquid crystal display device 2, the circuit board 4 has a liquid crystal drive circuit and an inverter circuit, and a plurality of electronic devices including an IC (Integrated circuit ) chip (heat generating component) 41 constituting the liquid crystal drive circuit and the inverter circuit are mounted on the front surface or the back surface thereof.

Further, wiring, not shown, which is made of a conductor electrically connected to an electronic device or the like, is formed on the circuit substrate 4. The circuit board 4 is fixed to the middle case 3 by a hook or the like not shown in the drawing, similarly to the liquid crystal display device 2. The liquid crystal display device 2 and the circuit substrate 4 are electrically connected through an FPC (Flexible Printed Circuits, flexographic printing plate), which is not shown in the figure.

The IC chip 41 is a thin rectangular microchip and functions as a GDC (Graphics Display Controller: drawing controller). The IC chip 41 generates heat, and this heat is transferred to the circuit substrate 4 to heat the circuit substrate 4.

The middle case 3 and the circuit substrate 4 are held between the liquid crystal display device 2 and the housing 5 by screws 6. The screw 6 is inserted into the screw hole 51 of the housing 5 from the rear of the housing 5, penetrates the through hole 42 of the circuit board 4 and the through hole 32 of the middle case 3, and is fastened to the metal boss 22 of the liquid crystal display device 2.

The case 5 is made of light-shielding synthetic resin and has a substantially rectangular parallelepiped box shape with an opening on the front surface side. The casing 5 is fitted to the transmissive casing 1 to form a closed frame, and accommodates the liquid crystal display device 2, the middle casing 3, and the circuit board 4 therein. The case 5 has a heat dissipation member 7 at a position opposed to the IC chip 41.

The heat dissipation member 7 is a member having good heat conductivity, and is preferably made of metal, and in the present embodiment, aluminum is used in terms of cost, ease of production, weight, and the like. The heat sink 7 is hollow and cylindrical, and is connected to the case 5 by insert molding on one side surface 71a of one end surface 71, and the other end surface 72 is opposed to the circuit board 4. One end surface 71 is formed so as to be in contact with the outside air without being bonded to the housing 5. In addition, the heat radiation member 7 can enhance the heat radiation effect by processing the aluminum anodized or the like to increase the surface area.

In the present embodiment, the heat conductive member 8 such as silicone rubber having elasticity and good heat conductivity is provided between the other end face 72 and the circuit board 4, but the other end face 72 may be directly brought into contact with the circuit board 4. The diameter of the heat transfer member 8 is set larger than the diameter (outer shape) of the other end surface 72 of the heat sink 7, and is preferably an electrically insulating material.

The heat radiation member 7 has a 1 st vent hole (vent hole) 73 communicating with the outside and a 2 nd vent hole (vent hole) 74 communicating with the inside. The 1 st ventilation hole 73 is formed by a hollow hole having a hole passing air from one end surface 71 toward the other end surface 72. The 2 nd vent hole 74 is formed by a recess 74a and a plurality of cutout portions 74b, and allows air to pass therethrough, wherein the recess 74a is a recess in which the other end surface 72 is recessed by 1 step to connect with the 1 st vent hole 73, and the cutout portions 74b are formed by cutting the other side surface 72a from the recess 74a to the other end surface 72 into a rectangular cross section.

A porous membrane 9 that passes air but does not pass liquid such as water is provided between the 1 st vent hole 73 and the 2 nd vent hole 74 for waterproofing. The porous film 9 is adhered to the recess 74a so as to close the hole of the 1 st ventilation hole 73.

By forming in this way, the air inside and outside the casing enclosed by the transmissive casing 1 and the casing 5 can be exchanged via the 1 st vent hole 73 and the 2 nd vent hole 74, and therefore, the occurrence of blurring in the display device can be suppressed. The air in the display device heated by the liquid crystal display device 2 and the IC chip 41 can be discharged to the outside, and heat in the display device can be dissipated.

Further, by forming the above, the heat of the IC chip 41 is transferred to the circuit board 4, the heat transfer member 8, and the heat dissipation member 7, and is dissipated to the air outside the display device, so that the heat of the IC chip 41 can be dissipated satisfactorily.

In addition, the heat transfer member 8 having high adhesion can satisfactorily transfer heat between the circuit board 4 and the heat sink 7, and thus can satisfactorily dissipate heat from the heat sink 7. Even when there is a variation in the dimensions of the circuit board 4, the case 5, and the heat sink 7 in terms of manufacturing, the thermal transfer member 8 having elasticity can be provided to absorb the variation between the components.

Further, since the heat radiation member 7 has a cylindrical shape, for example, compared with the case of a prism shape having the same volume, the surface area can be reduced, and the heat conductivity can be improved while minimizing the necessary arrangement space.

The IC chip 41, the heat transfer member 8, and the heat dissipation member 7, which are heat generating members, are provided at overlapping positions, so that heat of the IC chip 41 can be efficiently transferred to the heat dissipation member 7. In this case, the circuit board 4 is sandwiched between the IC chip 41 and the heat transfer member 8, and the copper foil pattern, the through holes, and the like of the circuit board 4 also act on heat conduction, so that local high temperature can be suppressed.

Embodiment 2 of the display device of the present disclosure is described with reference to fig. 3. The same parts and equivalent parts as those of embodiment 1 described above are denoted by the same reference numerals.

In embodiment 1, one of the side surfaces 71a is connected to the housing 5, but in this embodiment, one of the side surfaces 71a is formed so as to protrude from the housing 5 and be capable of contacting the outside air. By forming in this way, the contact area of the heat radiating member 7 with the outside air increases, and therefore, the heat of the heat radiating member 7 can be discharged more effectively.

In the present embodiment, the 1 st vent hole 73 has two barrier portions 75 protruding toward the center, which are different from each other. By forming in this way, the invasion of liquid or dust can be effectively prevented by the blocking action.

Also, the present disclosure is not limited to the above-described embodiments, and various modifications may be made within the scope of the gist of the present disclosure. For example, in the present embodiment described above, the liquid crystal display device 3 as the display means of the display device may be an organic EL (Electro Luminescence ) module.

In the above embodiment, the display device is configured to house only the liquid crystal display device 2 in the middle case 3, but the display device is not limited to the above embodiment, and for example, a pointer instrument may be housed in the middle case 3.

In the above embodiment, the heat transfer member 8 is in direct contact with the circuit substrate 4, but the heat transfer member 8 may be in contact with a member mounted on the circuit substrate 4.

The present disclosure relates to a display device for a vehicle, and is applicable to a display device for a vehicle mounted on a moving body including an automobile, a motorcycle, or an agricultural machine or a construction machine, for example.

Description of the reference numerals:

reference numeral 1 denotes a transmissive envelope;

reference numeral 2 denotes a liquid crystal display device (display section)

Reference numeral 3 denotes a middle casing;

reference numeral 4 denotes a circuit substrate;

reference numeral 5 denotes a housing (housing part);

reference numeral 6 denotes a screw;

reference numeral 7 denotes a heat radiating member;

reference numeral 73 denotes a 1 st vent hole (vent hole);

reference numeral 74 denotes a 2 nd vent hole (vent hole);

reference numeral 8 denotes a heat transfer member;

reference numeral 9 denotes a porous membrane.

Claims

1. A display device having at least a display member and a case member for housing the display member, wherein the case member has a heat radiating member having heat conductivity, the heat radiating member has a vent hole for passing air therethrough and is in contact with a heat generating member via a heat transmitting member, the vent hole has a porous film for not passing a liquid therethrough, and has a 1 st vent hole communicating with the outside and a 2 nd vent hole communicating with the 1 st vent hole and with the inside, the 2 nd vent hole is formed of a recess and a plurality of cutout portions, wherein the recess is a recess in which an end surface of the heat radiating member is recessed by 1 step and is connected to the 1 st vent hole, the cutout portion is formed by cutting a side surface from the recess to the heat radiating member into a rectangular cross section, and the porous film is provided in the recess.