JPWO2020090462A1 - Head-up display - Google Patents

Abstract

Provide a head-up display with reduced image blur. By rotating in conjunction with the display unit 2 that emits the display light L representing vehicle information, the reflection unit 30 that reflects the display light L and can rotate around a predetermined rotation axis P, and the reflection unit 30. An arm piece-shaped protruding portion 37 capable of rotating the reflective portion 30, an elastic portion 40 that urges the protruding portion 37 in a predetermined rotational direction by an elastic force, and a force that abuts on a surface of the elastic portion 40 located in the urging direction. A hard structure that rotatably holds the transmission unit 70, the power unit 80 that linearly moves the power transmission unit 70, and the reflection unit 30, and fixes the relative positions of the elastic unit 40, the power unit 80, and the rotation shaft P. And with a head-up display.

Description

The present invention relates to a head-up display.

Conventionally, as a head-up display, a configuration in which the angle of a concave mirror (41) is adjusted by using a lead screw (61c) as shown in Patent Document 1 is disclosed. Specifically, the protrusions (65h, 65i) of the position adjusting means (43) make point contact with the holding member (42) of the concave mirror (41), and the driving member (61a) drives the concave mirror (41). ) Rotates.

Japanese Unexamined Patent Publication No. 2009-73461

In such a configuration, there is a possibility that image blurring may occur when a large vibration occurs in the vehicle due to the engagement of the screwed portion and the gear portion included in the drive member (61a). Therefore, an object of the present invention is to pay attention to the above-mentioned problems and to provide a head-up display in which the possibility of image blurring is reduced.

In order to achieve the above object, the head-up display according to the present invention is
It is a head-up display that projects a virtual image by projecting display light onto the reflective and transmissive member of the vehicle.
A display unit that emits the display light that represents vehicle information,
A reflecting unit that reflects the display light and can rotate around a predetermined rotation axis,
An arm piece-shaped protrusion that can rotate the reflex part by rotating in conjunction with the reflex part,
An elastic portion that urges the protruding portion in a predetermined rotational direction by an elastic force, and an elastic portion.
A power transmission unit that comes into contact with a surface of the elastic portion located in the urging direction,
A power unit that linearly moves the power transmission unit and
A rigid structure that rotatably holds the reflective portion and fixes the relative positions of the elastic portion, the power portion, and the rotating shaft.
With
The reflective part is
A display mode in which the display light is projected onto the reflection / transmission member,
A pause mode in which the display light is not projected onto the reflection / transmission member,
Have,
The elastic portion is set so that the elastic force becomes stronger in the display mode.

According to the present invention, it is possible to provide a head-up display in which the risk of image blurring is reduced.

The figure which shows the appearance that the head-up display 1 of this disclosure was mounted on a vehicle C. The figure which shows the structure of the head-up display 1. The figure which shows a part of the head-up display 1 of a parking position. The figure which shows a part of the head-up display 1 of the torah position. The figure which shows a part of the head-up display 1 of a shorter position.

Hereinafter, the head-up display (HUD) 1 of the present disclosure will be described as an example of an embodiment and a modification mounted on the vehicle C, and will be described in the following order with reference to the accompanying drawings.
[First Embodiment]
1-1. Explanation of configuration 1-2. Description of mode [Modification example]
[Effect example]
[First Embodiment]
<1-1. Description of configuration>

As shown in FIG. 1, the HUD1 of the present disclosure can be assembled below the windshield WS provided in the vehicle C. The vertical direction of the drawing corresponds to the vertical direction Y of the vehicle C, the horizontal direction corresponds to the front-rear direction Z, and the depth direction corresponds to the horizontal direction X.

The HUD1 projects a virtual image V by projecting a display light L representing vehicle information on a windshield WS (reflection / transmission member) having a free curved surface shape inclined in the front direction of the vehicle. The HUD1 emits the display light L diagonally upward after the vehicle. The display light L emitted from the HUD1 is reflected by the windshield WS. A user (for example, a occupant of a vehicle C) who visually recognizes the display light L reflected by the windshield WS from the viewpoint EP can visually recognize the projected virtual image V as a floating display image behind the windshield WS.

The virtual image V alerts the occupants (users), for example, vehicle information such as speed and engine speed, route guidance displays such as turn-by-turns and maps, and warning displays such as blind spot monitors and speed limit excess warnings. Information that is highly necessary to be displayed is displayed. This provides a driving environment in which the need for viewpoint movement and eye focal length adjustment is reduced. In addition to the characters and icons indicating this information, the display image V also includes a background portion, which is, for example, rectangular in a plan view from the occupant.

Further, HUD1 has two main modes. One is a display mode in which the virtual image V can be visually recognized from the viewpoint EP by projecting the display light L onto the windshield WS as shown in FIG. The other is a pause mode (parking mode) in which the HUD1 does not project the display light L onto the windshield WS and the virtual image V cannot be visually recognized from the viewpoint EP. In the parking mode HUD1 that does not project the display light L onto the windshield WS, the display light L is incident on the external light (mainly sunlight) that is incident on the HUD1 from the direction of the windshield WS based on the principle of reversal of light rays. It is in a position where it does not reflect in the direction (the direction in which the display unit is optically present). As a result, when the HUD1 in which the vehicle C is considered to be stopped is in the parking mode, it is possible to prevent the display unit from being illuminated by external light and becoming in a high temperature state.

In the display mode HUD1, the optical path of the display light L can be changed by a configuration described later in order to adjust the height of the viewpoint EP in which the virtual image V can be visually recognized. In the present disclosure, as shown in the drawings, it is possible to change to three types: shorter display light Ls, center display light Lc, and torah display light Lt. As for the shorter display light Ls, in the display mode, the HUD1 projects the display light L onto the relatively lower part of the windshield SW, and projects the virtual image V. In the Torah display light Lt, the HUD1 projects the display light L onto the relatively upper part of the windshield SW and projects the virtual image V. In the center display light Lc, the virtual image V is projected by passing between the above-mentioned two display optical paths.

The configuration of HUD1 will be described with reference to FIG. The direction in the drawing corresponding to the direction of the vehicle C is the same as in FIG. FIG. 2 illustrates a state in which the reflecting unit 30 is the torah position Pt that reflects the display light L as the torah display light Lt. The coarse broken line Ps shows the outer shape when the concave mirror 31 of the reflecting portion 30 is in the shorter position, and the fine broken line Pp shows the outer shape when the concave mirror 31 is in the parking position Pp (rest position). In the present disclosure, the parking position is a position where the display light L is not projected onto the windshield WS, and in particular, a position where the center of the display light L is reflected in the direction B. Further, at each of the parking position Pp, the torah position Pt, the center position, and the shorter position Ps, the angle that the normal of the center of the reflecting surface 31a of the concave mirror 31 (the place where the center of the display light L is incident) has with respect to the direction B. Is, for example, 0 °, 18.5 °, 19.7 °, 21 °.

The HUD 1 includes a display unit 20, a reflection unit 30, a torsion spring 40, a control unit 50, a power transmission unit 70, and a power unit 80.

The display unit 20 is a member that emits the display light L. In the present disclosure, the light is emitted toward the direction F. As a member that emits the display light L, for example, a configuration using a TFT liquid crystal module, a configuration using an organic EL, a projector using a DMD (Digital Micro-mirror Device), or the like can be applied. In the configuration using the TFT liquid crystal module, for example, the display unit 20 is provided with the backlight unit and the liquid crystal display element connected to the control unit in a fixed state, and the liquid crystal display element that displays information under the control of the control unit. Is illuminated by the illumination light emitted from the backlight unit whose blinking is controlled by the control of the control unit to emit the display light L. However, it goes without saying that the effects of the configuration of the present disclosure can be exhibited as long as the configuration is capable of emitting display light other than those illustrated.

The reflecting portion 30 is provided with a concave mirror 31, a holder 32, a shaft 33, a locking hole 35 (power point), and a protruding portion 37 (action point).

The concave mirror 31 reflects the display light L while enlarging the display light L according to the shape of the free curved surface formed on the reflection surface 31a. As the concave mirror 31, a hard synthetic resin or inorganic glass can be applied to the base material, and for example, a configuration having a reflecting surface 31a formed by depositing silver can be applied. Further, it is desirable that the reflecting surface 31a has a shape capable of canceling the distortion of the display image V which is expected to occur in the windshield WS due to the shape of the free curved surface.

The holder 32 is a holding member for fixing the concave mirror 31 by adhesion or screwing. As the material, a hard metal such as magnesium or iron or a hard synthetic resin such as ABS resin can be applied. The concave mirror 31 can be appropriately held at a position that does not interfere with the reflection of the display light L. For example, when the holder 32 is held on the back surface with respect to the reflecting surface 31a as shown in the drawing, the possibility that the holder 32 cannot be seen from the viewpoint EP and that unintended light (stray light) reaches the viewpoint EP can be reduced.

The shaft 33 is formed integrally with the holder 32, for example. In order to define the rotation axis P along the direction X, it is desirable to provide one shaft 33 on each side surface of the holder 32 facing, for example, the direction X. The reflection unit 30 can switch between the display mode and the parking mode by rotating around the rotation axis P defined by the axis 33.

Further, the shaft 33 is a hard structure (not shown), and the rotating shaft P is held rotatably in a state where the relative positions of the fixed end 41 and the power unit 80, which will be described later, are fixed. As the hard structure, for example, a synthetic resin material such as ABS resin or a metal such as magnesium can be applied. This rigid structure may be a housing for accommodating each member constituting the head-up display 1, or may be a part of the vehicle body of the vehicle C. Further, in the structure in which the rigid structure holds the shaft 33, the shaft 33 is placed on the U-shaped invitation and can be suppressed by a leaf spring or the like with a force that does not hinder the rotation. However, the present invention is not limited to this, and any rigid structure that holds the rotation axis P so as to be defined may be used.

The locking hole 35 (power point) is a portion provided in the reflecting portion 30 for connecting the elastic portions. In the present disclosure, for example, it is a hole provided near the shaft. By locking the load end 42 of the torsion spring 40, which is an example of the elastic portion, to this hole, the reaction force of the elastic portion can be transmitted.

The protruding portion 37 (point of action) is an arm piece integrally provided on the holder 32. For example, in the present disclosure, it has a flat plate shape protruding from the holder 32. Further, the contact surface that comes into contact with the protrusion 71 is inclined by 18.5 ° in the rotation direction component with respect to the center of the concave mirror 31, and is present on the same plane as the rotation axis P. As a result, when the reflective member 30 is at the torah position Pt, the contact surface becomes perpendicular to the direction Y. Further, by providing the protrusion 37 in the center of the holder in the direction X component, the concave mirror 31 can be rotated relatively without causing distortion. The power transmission unit 70, which will be described later, can adjust the direction in which the reflection unit 30 reflects the display light L by displacing the position of the protrusion 37. The reflecting portion 30 is rotatably held around the rotation axis P, and is urged in the rotation direction by a torsion spring 40 described later. The angle of the reflecting portion 30 can be changed by pushing back the protruding portion 37 with a force larger than this urging force or pulling it back with a weak force.

In the present disclosure, the protruding portion 37 is formed integrally with the holder 32. However, the protruding portion 37 does not necessarily have to be formed integrally with the holder 32. The protrusion 37 may be provided on the concave mirror 31. Furthermore, the position of the reflecting portion 30 may be adjusted by displacing the position of the protruding portion 37 about a predetermined rotation axis. That is, the rotation of the rotatably provided protrusion may indirectly adjust the reflection angle via, for example, at least one gear.

The torsion spring 40 (elastic portion) is an elastic member that urges the reflective portion 30 in the direction of rotation. Hard metals such as hard steel and stainless steel can be applied as the material. In the present disclosure, the shaft 33 functions as a guide rod. Torque can be applied to the load end 42 about the center of the shaft 33 (rotating shaft P), which is a guide rod. The torque is determined according to the torque spring constant [N · mm / deg] peculiar to the torsion spring 40 and the deflection angle. Further, the fixed end 41 is fixed to the above-mentioned hard structure by means such as locking or adhesion, and the relative position between the rotating shaft P and the power unit 80 is kept constant as described above. One end of the torsion spring 40 of the load end 42 is bent in the direction R, and is locked in the locking hole 35 as described above. That is, they are assembled as shown in FIG.

Further, in the present disclosure, a load is applied to the torsion spring 40 in the winding direction. That is, it means that the torsion spring 40 is urged in the clockwise direction when viewed from the direction shown in the drawing. On the other hand, the protrusion 37 means that the protrusion 37 is pushed toward the direction B by the protrusion 71. This urging increases as the reflecting surface 31a of the reflecting portion 30 faces the direction U, in other words, as it approaches the shorter position. On the other hand, this urging becomes smaller as it approaches the parking position.

Further, even when the parking position is reached, the torsion spring 40 does not return to its own free angle and keeps bending. This is because the purpose of the torsion spring 40 to bias is to bias in any of the parking mode, the display mode, and the transition mode in between. By urging with a torque equal to or higher than a predetermined value, even if a torque in the opposite direction is generated due to an impact applied to the HUD1, the locking hole 35, the reflecting portion 30, the protruding portion 37, the protrusion 71, The power transmission unit 70 and the power 80 are urged, and even if the power transmission unit and the power unit 80 are connected to each other, the image blurring and backlash due to the rattling caused by the gap that may cause backlash inside the power unit 80 are generated. It is possible to reduce the possibility of producing a sound due to backlash.

Further, as described above, it is preferable to set the positions of both ends of the elastic portion so that the bias in the display mode is stronger than that in the parking mode. This is because the vehicle C is generally not in the running state in the parking mode, while the vehicle C is often in the running state in the display mode. This means that there is a high possibility that a large impact will be applied to the head-up display 1 in the display mode. That is, if the positions of both ends of the elastic portion are set so that the bias in the display mode is stronger than that in the parking mode, the possibility of image blurring can be efficiently reduced.

By the way, due to the above circumstances, the larger the torque spring constant [N · mm / deg] of the torsion spring 40, the more resistant it is to the torque in the opposite direction. However, if it is made too strong, the concave mirror 31 (reflection surface 31a) will be distorted. This also leads to distortion of the virtual image V, so it is necessary to perform sufficient urging with a spring load as small as possible. The configuration according to the setting method will be described in detail later.

The control unit 50 is provided with a storage unit such as a ROM or RAM (not shown) used for storing a predetermined program or various data, a storage area at the time of calculation, a CPU for performing calculation processing according to the predetermined program, an input / output interface, and the like. Microcomputer can be applied. The control unit 50 generates an image to be displayed on the display unit 20, controls the display of the display unit, and controls the illuminance of the lighting means based on the vehicle information received from the in-vehicle device external to the HUD1. The control unit 50 is electrically connected to the display unit 20, the power unit 80, and an external electronic device of the HUD 1, and also controls the drive of the power unit 80.

The power unit 80 is a power unit that causes a power transmission unit 70, which will be described later, to perform a linear motion along a direction non-parallel to the rotation axis P. In the present disclosure, for example, a linear motion is performed in the direction Z. As described above, it is electrically connected to the control unit 50 to control its operation.

For the power unit 80, for example, a configuration using a lead screw can be applied. Specifically, a drive unit such as a motor that rotates the rotating shaft in response to an input signal, a screw shaft that rotates in response to the rotation, a ring-shaped nut portion that is screwed into the screw shaft, and a guide that suppresses the rotation of the nut portion. It has a part, and the power transmission part 70 described later is fixed to a nut. The nut portion whose rotation is suppressed by the guide portion can perform a linear motion along the axial direction of the screw shaft rotated by the drive portion.

For example, a rigid rigid resin material can be applied to the power transmission unit 70, and the angle of the reflection member 30 is adjusted by performing a linear motion by the power of the power unit 80 and pushing the protrusion 37 through the protrusion 71 provided on the power transmission unit 70. can do. When the power unit 80 has the above-mentioned configuration using a lead screw, it is fixed to the nut portion, and the nut portion abuts on the guide portion via the fixed power transmission portion 70 to suppress its own rotation. You may.
<1-2. Mode description>

The state of urging in each mode will be described with reference to FIGS. 3, 4, and 5.
FIG. 3 shows a state of urging when the concave mirror 31 is at the parking position Pp. Tp indicates the torque applied to the reflective member 30 by the torsion spring 40 at the parking position Pp. Fp indicates the force with which the protrusion 37 abuts on the protrusion 71. The contact force Fp is generated perpendicular to the contact surface of the protrusion 37. fp indicates the Z-direction component force (holding component force) in Fp. By increasing the holding component force fp, it is possible to prevent the power unit 80 from rattling even when a stronger impact is applied. This is because the linear motion directions of the power unit 80 and the power transmission unit 70 coincide with the direction Z. Tx, Fx, and fx (x is t or s) in FIGS. 4 and 5 indicate torque or force or holding component force at the torah position Pt or the shorter position Ps.

Here, the angle formed by the contact force Fp and the holding component force fp is 18.5 °. This can be seen from the fact that the angle formed by the protrusion 37 with the concave mirror 31 is 18.5 °, and the concave mirror 31 is perpendicular to the direction Z. In other words, it can be said that the angle (contact angle) at which the protruding portion 37 comes into contact with the power transmission portion 70 is 18.5 °. In addition, the holding component force fp is a magnitude obtained by multiplying the contact force Fp by the value of the cosine of 18.5 °.

Similarly, the holding component force ft is a magnitude equal to the contact force Ft, and the holding component force fs is a magnitude obtained by multiplying the contact force Fs by the value of the cosine of 2.5 °. That is, the holding component force f can be applied more efficiently when the contact angle is closer to 0 °.

Generally, the angle at which the concave mirror of the HUD rotates from the shorter position to the torah position is within 3 °. Further, of the shorter position and the torah position, the angle required to rotate from the position close to the parking position to the parking position is 10 ° or more. Therefore, if the contact angle reaches 0 ° when the reflective portion is near the parking position, the contact angle deviates from 0 ° when the reflective portion subsequently reaches the display mode. If the stress is dispersed in this way, even if the contact force Fx is large, the holding component force fx cannot be efficiently applied and becomes small.

Therefore, as shown in the present disclosure, if the contact angle is set to be around 0 ° from the parking position Pp in the display mode, stress dispersion is reduced as much as possible and a head-up display with reduced image blurring is provided. can.

Furthermore, in the configuration where the contact angle is at a right angle between the torah position and the shorter position, whichever is closer to the parking position, the position where there is no stress dispersion is set at least one of the display modes. , Image blur can be reduced more efficiently.

More preferably, the torque spring constant is k [N ・ mm / deg], the angle as a variable is θ [deg], the contact angle of one of the toller position and the shorter position, which is closer to parking, is θt [deg], and the other. When the contact angle at is θs (that is, the angle when the reflective part is rotated from one position to the other in the display mode is added to θt) [deg], θ · k · cos θ is set. It is desirable to set θt so that the absolute value when integrated from θt to θs is maximized. According to this, the stress dispersion can be further reduced and the image blur can be efficiently reduced.

In this way, it has become possible to provide a head-up display that reduces the risk of image blurring.

Although the head-up display of the present invention has been described by way of examples in the configuration of the above-described embodiment, the present invention is not limited to this, and other configurations also deviate from the gist of the present invention. Of course, it is possible to make various improvements and change the display within the range that does not apply. For example, in the present disclosure, a configuration using a holder in addition to the reflecting surface and the protruding portion is shown as the reflecting portion. However, it is sufficient that the holder is not provided and at least the reflecting surface 31a and the protruding portion move in conjunction with each other.

In addition, a torsion spring was used as the elastic part. However, other than the torsion spring, any other configuration may be used as long as it is an elastic portion capable of urging the reflecting portion in the rotational direction. For example, it may be configured by a coil spring such that the expansion / contraction direction connecting the fixed end and the elastic end (moving end) is at the twisted position with respect to the rotating shaft. If the expansion / contraction direction is not in the twisted position, torque cannot be generated with respect to the rotating shaft, and as a result, urging cannot be performed. However, if it is a twisted position and the relative position of the fixed end, the rotating shaft, and the power part is kept constant by the hard structure as described above, torque is generated if the moving end is stopped at the reflecting part. You can urge.

Further, in the present disclosure, the positions of the reflecting portions 30 are the parking position Pp, the torah position Pt, the center position, and the shorter position Ps in order from the parking position. However, in a design in which the parking position is such that the reflecting surface 31a faces the direction F and the traveling direction of the vehicle, the position of the reflecting portion in the display mode closest to the parking position is the shorter position. In such a case, if the contact angle is set to 0 ° at the shorter position close to the parking position, the head-up display can efficiently reduce the risk of image blurring.
[Effect example]

First, the head-up display 1 of the present disclosure is a head-up display 1 that projects a virtual image V by projecting the display light L onto the reflection / transmission member WS of the vehicle C.
A display unit 2 that emits a display light L that represents vehicle information,
A reflecting unit 30 that reflects the display light L and can rotate around a predetermined rotation axis P.
An arm piece-shaped protrusion 37 capable of rotating the reflective portion 30 by rotating in conjunction with the reflective portion 30 and
An elastic portion 40 that urges the protruding portion 37 in a predetermined rotational direction by an elastic force,
A power transmission unit 70 that comes into contact with a surface of the elastic unit 40 located in the urging direction,
A power unit 80 that linearly moves the power transmission unit 70,
A rigid structure that rotatably holds the reflective portion 30 and fixes the relative positions of the elastic portion 40, the power portion 80, and the rotating shaft P.
With
The reflection unit 30
A display mode that projects the display light L onto the reflection / transmission member WS,
A parking mode that does not project the display light L onto the reflection / transmission member WS,
Have,
The elastic portion 40 is a head-up display in which the elastic force is set to be stronger in the display mode.
According to this configuration, it is possible to provide a head-up display in which an impact is easily applied to the head-up display 1 and image blurring can be reduced at least efficiently when the vehicle C is in a runnable state.

Secondly, the head-up display 1
The protrusion 37
In a plan view from the rotation axis P, the power transmission unit 70 is always in contact with the power transmission unit 70 in the direction of rotation by point contact.
The contact angle formed by the contact direction and the linear motion direction Z is
The head-up display is smaller in display mode than in parking mode.
According to this configuration, it is possible to provide a head-up display capable of preventing image blurring more efficiently.

Third, the head-up display 1
The reflection unit 30
It can be displaced to multiple display positions (Torah position Pt and Shorter position Ps) in display mode.
In parking mode, it can be displaced to the parking position Pp,
The contact angle is
This is a head-up display in which the reflection unit 30 is 0 ° when it is in at least one display position among the display positions in the display mode.
According to this configuration, it is possible to provide a head-up display which has a display position where stress dispersion does not occur at at least one position and efficiently reduces the possibility of image blurring.

Fourth, the head-up display 1 is a head-up display in which the contact angle is 0 ° at the display position closest to the parking position among the plurality of display positions.

C Vehicle 1 Head-up display (HUD)
WS windshield (reflection and transmission member)
V Virtual image EP Viewpoint L Display light

2 Display 3 Reflector 31 Concave mirror 31a Reflector 32 Holder 33 Shaft 35 Locking hole (power point)
37 Protruding part (point of action)
40 Torsion spring (elastic part)
41 Load end 42 Fixed end 70 Power transmission part 71 Protrusion 80 Power part

P rotation axis (fulcrum)

Claims (4)

It is a head-up display that projects a virtual image by projecting display light onto the reflective and transmissive member of the vehicle.
A display unit that emits the display light that represents vehicle information,
A reflecting unit that reflects the display light and can rotate around a predetermined rotation axis,
A protruding portion that can rotate the reflective portion by rotating in conjunction with the reflective portion,
An elastic portion that urges the protruding portion in a predetermined rotational direction by an elastic force, and an elastic portion.
A power transmission unit that comes into contact with a surface of the elastic portion located in the urging direction,
A power unit that linearly moves the power transmission unit and
A rigid structure that rotatably holds the reflective portion and fixes the relative positions of the elastic portion, the power portion, and the rotating shaft.
With
The reflective part is
A display mode in which the display light is projected onto the reflection / transmission member,
A pause mode in which the display light is not projected onto the reflection / transmission member,
Have,
The elastic portion is set so that the elastic force becomes stronger in the display mode.
Head-up display. The protrusion
In a plan view from the rotation axis, the power transmission unit is always in contact with the power transmission unit in the direction of rotation by point contact.
The contact angle formed by the direction of contact and the direction of linear motion is
The head-up display according to claim 1, wherein the display mode is smaller than the hibernate mode. The reflective part is
It can be displaced to multiple display positions in the display mode.
In the hibernation mode, it can be displaced to the hibernation position.
The contact angle is
The head-up display according to claim 2, wherein the reflection portion is 0 ° when it is in at least one display position among the display positions. The contact angle is
The head-up display according to claim 3, wherein the display position closest to the rest position among the plurality of display positions is 0 °.

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