JP7622740B2 - Head-up display device - Google Patents

Description

The present disclosure relates to a head-up display device.

A head-up display (HUD) device is known that is installed in the dashboard of a vehicle, emits display light that represents an image on the windshield, and displays a virtual image of the image. For example, Patent Document 1 describes a HUD device in which a relatively rigid material such as metal is used for the housing.

JP 2016-103008 A

If the vehicle receives an excessive impact, the dashboard is designed to break down appropriately to absorb the impact, ensuring the safety of the vehicle occupants and pedestrians. For the same reason, it is desirable for the HUD device installed in the dashboard to also be able to absorb the impact if it receives an excessive impact. For example, as described in Patent Document 1, if a material with a relatively high rigidity is used for the housing of the HUD device, the demand for shock absorption increases for the above reasons.

This disclosure has been made in consideration of the above-mentioned situation, and aims to provide a head-up display device that can absorb impacts well.

In order to achieve the above object, a head-up display device according to the present disclosure includes:
a housing having a first case and a second case and housing a display unit that emits display light to display an image;
a connecting portion that connects the first case and the second case and has a lower rigidity than the first case and the second case,
The connecting portion is
a first portion fixed to the first case;
a second portion fixed to the second case;
a weak portion located between the first portion and the second portion and weaker than the first portion and the second portion due to the connecting portion itself ;
It is installed in the dashboard of the vehicle.

The present disclosure provides excellent shock absorption.

FIG. 1 is a schematic configuration diagram of a head-up display (HUD) device according to an embodiment of the present disclosure. FIG. 4 is an enlarged perspective view of the vicinity of a connecting portion between the lower case and the middle case according to the embodiment. 3 is a cross-sectional view of the lower case, the middle case, and the connecting portion according to the embodiment taken along line AA in FIG. 2 . FIG. 4 is an exploded perspective view of a lower case, a middle case, a connecting portion, and the like according to the embodiment. FIG. 11 is a schematic cross-sectional view illustrating a connecting portion according to a modified example.

One embodiment of the present disclosure is described with reference to the drawings.

The head-up display (HUD) device 100 according to this embodiment is provided in the dashboard (also called the instrument panel) of a vehicle, and emits display light 2 representing an image onto a windshield 1, as shown in Fig. 1, and displays a virtual image of the image. The virtual image is displayed in front of the vehicle through the windshield 1.

In the following, each configuration may be explained using the left-right, up-down, and front-to-rear directions of the vehicle. In the appropriate drawings, the X-axis along the left-right direction, the Y-axis along the up-down direction, and the Z-axis along the front-to-rear direction are shown.

As shown in FIG. 1, the HUD device 100 comprises a display unit 10, a first mirror 21, a second mirror 22, a housing 30, a control board 40, and a connecting unit 50.

The display unit 10 displays an image and emits display light 2 representing the image toward the first mirror 21. The display unit 10 has, for example, an LCD (Liquid Crystal Display) and a backlight that illuminates the LCD from behind. The LCD is, for example, a TFT (Thin Film Transistor) type. The backlight is, for example, composed of an LED (Light Emitting Diode), a light-guiding member, etc.

The first mirror 21 reflects the display light 2 from the display unit 10 toward the second mirror 22. The first mirror 21 is, for example, a concave mirror.

The second mirror 22 reflects the display light 2 from the first mirror 21 toward the windshield 1 located outside the HUD device 100. The second mirror 22 is, for example, a concave mirror. The second mirror 22 is driven to rotate about a rotation axis 22a by a drive mechanism (not shown).

The housing 30 comprises a lower case 31, a middle case 32, and an upper case 33.

The lower case 31 is box-shaped and opens upward, and is made of, for example, metal. The lower case 31 supports the display unit 10 via a support member 10a provided on the bottom surface of the lower case 31. The lower case 31 covers the middle case 32 from below, and houses the display unit 10 and control board 40 inside. The lower case 31 is connected to the middle case 32 by a connecting portion 50.

The middle case 32 is box-shaped and opens upward, and is made of, for example, metal. The middle case 32 houses the second mirror 22 and a drive mechanism (not shown) inside. An opening H1 is formed at the rear bottom of the middle case 32, through which the display light 2 from the display unit 10 to the first mirror 21 passes.

The upper case 33 is formed of a light-shielding resin or metal, and covers the middle case 32 from above. The upper case 33 has an opening H2 and a shielding wall 33a, and is formed in a frame shape. The opening H2 passes the display light 2 traveling from the second mirror 22 toward the windshield 1. The shielding wall 33a prevents external light, such as sunlight, from entering the housing 30. The upper case 33 is provided with a cover glass (not shown) that closes the opening H2. The upper case 33 supports, for example, the first mirror 21. The upper case 33 is fixed to the middle case 32 by known fixing means, such as a screw S.

The control board 40 is a printed circuit board equipped with a microcomputer that controls the overall operation of the HUD device 100. The control board 40 controls the display position of the virtual image in the vertical direction by controlling a drive mechanism (not shown) and rotating the second mirror 22. The control board 40 also communicates with systems such as an ECU (Electronic Control Unit) that controls each part of the vehicle, and causes the display unit 10 to display an image showing information about the vehicle.

The connecting parts 50 shown in FIG. 1 connect the lower case 31, which is an example of a first case, and the middle case 32, which is an example of a second case, at multiple locations including the front and rear parts. Of these multiple locations, FIG. 2 is a perspective view showing connecting parts located at the front parts of the lower case 31 and the middle case 32. As shown in FIG. 2 and FIG. 4, the front parts of the lower case 31 and the middle case 32 are connected by three connecting parts 50. Since the configuration of each connecting part 50 is the same, the following describes the configuration related to an arbitrary connecting part 50, and the description of the configuration related to the other connecting parts 50 is omitted. Note that the rear parts of the lower case 31 and the middle case 32 are connected by one or more connecting parts 50, although not shown.

The connecting portion 50 is formed from a material, such as resin, that has lower rigidity than the lower case 31 and the middle case 32, which are formed from metal. As shown in Fig. 3, the connecting portion 50 includes a first portion 51, a second portion 52, and a fragile portion 53. The HUD device 100 also includes a first fixing portion 61, a second fixing portion 62, and a pair of sub-fixing portions 63. For example, the first fixing portion 61, the second fixing portion 62, and the sub-fixing portion 63 are each formed from the same screw.

The first part 51 is a part fixed to the lower case 31, and as shown in Fig. 3, has a cylindrical part 511 formed along the axis AX, and a pair of cup parts 512, 513 adjacent to the cylindrical part 511. Meanwhile, the lower case 31 is formed with a fixed part 310 to which the first part 51 is fixed. The fixed part 310 has a recess 311 into which the lower end of the cylindrical part 511 is inserted, and a pair of bosses 312, 313 corresponding to the pair of cup parts 512, 513.

The tube portion 511 of the first part 51 is a cylindrical portion formed along the axis AX parallel to the Y axis. The lower end of the tube portion 511 is inserted into the recess 311 of the lower case 31. The tube portion 511 is fixed to the recess 311 from below by a first fixing part 61 consisting of a screw. The first fixing part 61 is located on the axis AX, and is screwed into the inside of the tube portion 511 through a through hole formed in the recess 311.

The cup portion 512 of the first part 51 is cup-shaped and opens upward. The upper surface of the cup portion 512 is formed flush with the upper surface of the tube portion 511. The bottom of the cup portion 512 is formed with a recessed portion that is recessed upward. The upper end of the boss 312 of the lower case 31 is inserted into the recessed portion formed in the bottom of the cup portion 512. The boss 312 is formed in a cylindrical shape. The cup portion 312 is fixed to the boss 312 from above by a secondary fixing portion 63 consisting of a screw. The secondary fixing portion 63 extends parallel to the axis AX at a position off the axis AX, passes through a through hole formed in the cup portion 512, and is screwed into the inside of a bottomed hole formed in the boss 312.

The cup portion 513 of the first part 51 is located on the opposite side of the cup portion 512 across the tube portion 511. The cup portion 513 is fixed from above to the boss 313 formed on the lower case 31 by a secondary fixing portion 63 consisting of a screw. The relationship between the cup portion 513 and the boss 313 formed on the lower case 31 is the same as the relationship between the cup portion 512 and the boss 312.

The second part 52 is a part that is fixed to the middle case 32, and is formed in a cylindrical shape extending along the axis AX as shown in Fig. 3. On the other hand, the middle case 32 is formed with a fixed part 320 that protrudes toward the connecting part 50 and to which the second part 52 is fixed as shown in Fig. 2. As shown in Fig. 3, the second part 52 is fixed from above to the fixed part 320 of the middle case 32 by a second fixing part 62 consisting of a screw. The second fixing part 62 is located on the axis AX, and is screwed into the inside of the cylindrical second part 52 through a through hole formed in the fixed part 320.

The fragile portion 53 is located between the first portion 51 and the second portion 52, and is weaker than the first portion 51 and the second portion 52. Specifically, the fragile portion 53 is formed between the lower end portion 52a of the second portion 52 and the upper surface of the tubular portion 511 of the first portion 51, and is located on the axis AX. The fragile portion 53 has an outer diameter centered on the axis AX smaller than that of the lower end portion 52a of the second portion 52, and is formed so as to gradually decrease in diameter as it approaches the first portion 51 from the second portion 52.

The connecting portion 50 formed as described above is formed with a strength such that the weak portion 53 and the first portion 51 break when the HUD device 100 receives an excessive impact via the vehicle, but does not break under normal circumstances when no excessive impact is applied. The strength can be determined by experiment. Furthermore, under normal circumstances, the connecting portion 50 can maintain the connection between the lower case 31 and the middle case 32 while absorbing impacts due to the elasticity of the resin and the flexible shape of the weak portion 53.

(1) The HUD device 100 described above includes a connecting portion 50 that connects a lower case 31 (an example of a first case) and a middle case 32 (an example of a second case) and has a lower rigidity than the lower case 31 and the middle case 32. The connecting portion 50 includes a first portion 51 fixed to the lower case 31, a second portion 52 fixed to the middle case 32, and a fragile portion 53 that is located between the first portion 51 and the second portion 52 and is fragile than the first portion 51 and the second portion 52.
According to this configuration, when the vehicle receives an excessive impact, the weak portion 53 of the connecting portion 50 breaks, and the middle case 32 and the lower case 31 can be separated. In other words, when an excessive impact is received, the HUD device 100 breaks appropriately, and the impact can be absorbed well. This makes it possible to mitigate a part of the impact that may be applied to the vehicle occupants, etc.

(2) The lower case 31 also supports the display unit 10 .
Since the lower case 31 supporting the display unit 10 is heavy relative to other parts of the housing 30, if an excessive impact is received and the weak part 53 of the connecting part 50 breaks, the lower case 31 is likely to separate from the middle case 32 and fall. In other words, with this configuration, the HUD device 100 is moderately prone to breakage when subjected to an excessive impact.

(3) The HUD device 100 further includes a first fixing portion 61 that fixes the first portion 51 to the lower case 31 and a second fixing portion 62 that fixes the second portion 52 to the middle case 32. The first fixing portion 61, the second fixing portion 62, and the fragile portion 53 are located on the same axis AX.
This configuration ensures resistance to vibrations, particularly in the vertical direction, during normal times, while when an excessive impact is received, the first fixed portion 61 and the second fixed portion 62 move so as to deviate from each other's axis line AX, acting to break the fragile portion 53. In other words, it is possible to achieve both normal impact resistance and fragility of the HUD device 100 when an excessive impact is received.

(4) In addition, the HUD device 100 includes the secondary fixing portion 63 that fixes the first portion 51 to the lower case 31 at a position offset from the axis line AX.
With this configuration, it is possible to prevent the connecting portion 50 from rotating about the axis line AX relative to the lower case 31.

(5) The lower case 31 and the middle case 32 are made of metal, and the connecting portion 50 is made of resin.
If the lower case 31 and the middle case 32 are made of metal, the lower case 31 and the middle case 32 themselves are unlikely to break when subjected to an excessive impact, and so there is a high demand for shock absorption. On the other hand, by forming the connecting part 50 from resin, it is possible to break appropriately when subjected to an excessive impact, and to facilitate good shock absorption. Note that the lower case 31 or the middle case 32 may be made of resin as long as it has a higher rigidity than the connecting part 50. However, when at least one of the lower case 31 and the middle case 32 is made of metal, the connecting part 50 made of resin is preferable.

Note that this disclosure is not limited to the above embodiments and drawings. Appropriate modifications (including the deletion of components) may be made without departing from the spirit of this disclosure.

The shape of the connecting portion 50 is not limited to the above example, and can be modified as appropriate. For example, as shown in Fig. 5, a connecting portion 50M according to a modified example may be adopted. Hereinafter, this modified example will be described using the same reference numerals for each part having the same function as the above embodiment.
The connecting portion 50M according to the modified example includes a first portion 51, a second portion 52, and a fragile portion 53. The first portion 51 is fixed from above to the fixed portion 310 of the lower case 31 by a first fixing portion 61 made of a screw. The first portion 51 is formed, for example, in a cylindrical shape. The second portion 52 is fixed from above to the fixed portion 320 of the middle case 32 by a second fixing portion 62 made of a screw. The second portion 52 is formed, for example, in a cylindrical shape. The fragile portion 53 is formed in a plate shape connecting the first portion 51 and the second portion 52. For example, the fragile portion 53 is formed thinner than the first portion 51 and the second portion 52, and is therefore fragile than the first portion 51 and the second portion 52. This connecting portion 50M also allows the HUD device 100 to break appropriately when subjected to an excessive impact, thereby absorbing the impact well. In addition, when the connecting portion 50M is employed, the auxiliary fixing portion 63 can be omitted.

The weak portion 53 in the connecting portion 50 is not limited to the above example, and may have any shape as long as it is weaker than the first portion 51 and the second portion 52. For example, the weak portion 53 may be a groove portion formed between the first portion 51 and the second portion 52 of the connecting portion 50.

The number of connecting parts 50 connecting the lower case 31 and the middle case 32 can be determined arbitrarily depending on the design. Also, one of the pair of auxiliary fixing parts 63 may be omitted. Similarly, one of the pair of cup parts 512, 513 and one of the pair of bosses 312, 313 may be omitted. Also, a configuration in which the middle case 32 and the upper case 33 are connected by connecting parts 50 can be adopted. In this case, the middle case 32 is an example of the first case, and the upper case 33 is an example of the second case.

The connecting parts 50, 50M may be formed from any known material such as plastic or elastomer, and the material may be any desired one.

In the above, an example has been shown in which the first fixing portion 61, the second fixing portion 62, and the sub-fixing portion 63 are each composed of the same screw, but they may include different types of screws. Furthermore, the first fixing portion 61, the second fixing portion 62, and the sub-fixing portion 63 are not limited to screws, and may be composed of known fixing members that use, for example, pins, hooks, etc.

The configuration of the optical system within the HUD device 100 can be any configuration as long as it can emit the display light 2 from the display unit 10 to the windshield 1, and the number, shape and arrangement of the mirrors that reflect the display light 2 can be changed as appropriate.

Although the above describes a display unit 10 using an LCD, the configuration of the display unit 10 is not limited and is arbitrary. For example, the display unit 10 may use an OLED (Organic Light-Emitting Diode). The display unit 10 may also include a DMD (Digital Micromirror Device) and a transmissive screen that receives light reflected by the DMD and displays an image.

The translucent member that reflects the HUD device 100 toward the user is not limited to the vehicle windshield 1, but may be a combiner composed of a plate-shaped half mirror, a hologram element, etc.

The type of vehicle on which the HUD device 100 is installed is not limited, and it can be applied to various vehicles such as four-wheeled motor vehicles and motorcycles.

In the above explanation, explanations of well-known technical matters have been omitted as appropriate to facilitate understanding of this disclosure.

REFERENCE SIGNS LIST 100 Head-up display (HUD) device 1 Windshield 2 Display light 10 Display unit 21 First mirror 22 Second mirror 30 Housing 31 Lower case (an example of a first case)
310 Fixed portion 311 Recess 312, 313 Boss 32 Inner case (an example of a second case)
320 Fixed part 33 Upper case 40 Control board 50 Connecting part 51 First part 511 Cylindrical part 512, 513 Cup part 52 Second part 53 Fragile part 61 First fixing part 62 Second fixing part 63 Sub-fixing part AX Axis

Claims (5)

a housing having a first case and a second case and housing a display unit that emits display light to display an image;
a connecting portion that connects the first case and the second case and has a lower rigidity than the first case and the second case,
The connecting portion is
a first portion fixed to the first case;
a second portion fixed to the second case;
a weak portion located between the first portion and the second portion and weaker than the first portion and the second portion due to the connecting portion itself ;
A head-up display device is installed in the dashboard of a vehicle. The first case is located below the second case and supports the display unit.
The head-up display device according to claim 1 . a first fixing portion that fixes the first portion to the first case;
a second fixing portion that fixes the second portion to the second case,
The first fixed portion, the second fixed portion, and the weak portion are located on the same axis line.
The head-up display device according to claim 1 or 2. a secondary fixing portion that fixes the first portion to the first case at a position offset from the axis;
The head-up display device according to claim 3 . At least one of the first case and the second case is made of metal,
The connecting portion is formed of resin.
The head-up display device according to any one of claims 1 to 4.

Images