JPH0796771A - Display position adjuster of head up display - Google Patents

Abstract

PURPOSE:To reduce the number of part items and to decrease the cost of production as well as to simplify the procedure of work by omitting a limit switch for setting both upper and lower limits of the allowable rotational range of a rotary mirror in a head up display. CONSTITUTION:A rotary mirror 8 is set up on an optical path of display light, varying an optical axis of this display light. Among four gears 14, 16, 17 and 18 rotating the rotary mirror 8, a projection 23 for locking the fourth gear 18 is formed in one end side of a tooth part of the third gear 17 and a recess 24 for racing the fourth gear 18 at the other end side, respectively. Each forming position of both these projection and recess parts 23 and 24 is set according to both upper and lower limits of the allowable rotational range of the rotary mirror 8. If the fourth gear 18 becomes locked and raced by the projection 23 and the recess 24, the rotary mirror 8 becomes unrotated, whereby a turning angle of the rotary mirror 8 is held down to the allowable rotational range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display position adjusting device for a head-up display, and more particularly to adjusting the display position of a display image (characters, figures, symbols, etc.) displayed as a virtual image on a vehicle head-up display. The present invention relates to a display position adjusting device for a head-up display.

[0002]

2. Description of the Related Art A head-up display for displaying speed and front end position of a vehicle in front of a windshield of a vehicle, and rear end position of a vehicle behind a rear window of a vehicle depends on the seat height of the driver, seat position, etc. Since the display image may not be visible in some cases, a display position adjusting device that can adjust the display position by the driver's operation is incorporated.

FIG. 7 conceptually shows a head-up display in which a display position adjusting device is incorporated. Figure 7
In the figure, 1 represents the windshield of the vehicle.
Reference numeral 2 denotes a display device having a lamp 3 built-in and a liquid crystal panel 4 arranged on the front surface. Also, 5 and 6 are
Each represents a fixed mirror arranged on the optical path of the display light from the display 2. Reference numeral 7 denotes a rotating mirror (optical axis variable body) 8 that changes the optical axis of the display light according to the rotation angle.
And a display unit 11 including a plurality of gears 9 and a motor 10 for rotating the rotating mirror 8. Reference numeral 12 represents a combiner provided on the inner surface of the windshield 1.

A concrete structure of the conventional display position adjusting device 7 is shown in FIGS. 8 (A) and 8 (B).

In FIGS. 8A and 8B, the rotary mirror 8 has a rotary shaft 8a. The rotating shaft 8a is rotatably supported by a pair of rotating mirror support portions 13a formed on the base member 13 so as to face each other.

A gear (referred to as a first gear) 14 having a substantially semicircular shape is fixed to the rotary mirror 8. First gear 14
A circular gear (referred to as a second gear) 16 in which a rotating shaft 15 is supported by a base member 13 is meshed with the shaft. A substantially fan-shaped gear (referred to as a third gear) 17 is fixed to the rotating shaft 15 of the second gear 16. A circular gear (referred to as a fourth gear) 18 is meshed with the third gear 17. The fourth gear 18 is fixed to the output shaft 10a of the motor 10 supported by the base member 13. The motor 10 is a reversible motor capable of reversing. Since the mirror rotating means 11 is configured as described above, the rotational force of the motor 10 is transmitted to the output shaft 10a, the fourth gear 18, the third gear 17, the second gear 16, and the first gear 14. The rotating mirror 8 can be rotated to change the optical axis of the display light.

The rotary mirror 8 has a U-shaped portion 19a.
A stay 19 having is provided. In addition, the base member 13 includes one end 19 of the U-shaped portion 19 a of the stay 19.
A limit switch 20 that performs a switching operation to be turned on when abutting on b, and another limit switch 21 that performs a switching operation to turn on when abutting on the other end portion 19c of the U-shaped portion 19a are provided. These limit switches 20 and 21 are for stopping the rotary mirror 8 at the rotation limit position, and have an action of stopping the motor 10 by the switching operation to be turned on.

A spring 22 is provided between the rotary mirror 8 and the base member 13 to prevent backlash.

[0009]

However, in the above-mentioned conventional display position adjusting device, since the limit switch for stopping the rotary mirror at the rotation limit position is provided as described above, the number of parts is large. There were problems such as high cost and the need to install limit switches.

The present invention has been made to solve the above problems, and provides a display position adjusting device for a head-up display, which can reduce the number of parts, cost, and work. With the goal.

[0011]

In order to solve the above-mentioned problems, a display position adjusting device for a head-up display according to the present invention includes an optical axis variable body arranged on an optical path of display light, a drive side gear, and a drive side gear. A driven gear which meshes with the driven gear, and a rotating means for transmitting a driving force via the driven gear and the driven gear to rotate the variable optical axis body, When the optical axis variable body reaches the rotation limit position in one of the driving side gear and the driven side gear,
It is characterized in that an idling lock portion for idling or locking the drive side gear is provided.

[0012]

The display light travels on the optical axis defined by the variable optical axis, and the display image is displayed at the display position corresponding to this optical axis.

When it is desired to adjust the display position, the rotating means rotates the optical axis variable body by the operation of the driver. When the optical axis variable body rotates and reaches the rotation limit position, the idle lock unit idles or locks the drive gear. When the drive-side gear idles or is locked, power is not transmitted to the driven-side gear, and the optical axis variable body does not rotate any more. Therefore, the optical axis variable body stops at the rotation limit position.

Therefore, the limit switch becomes unnecessary,
It is possible to reduce the number of parts, cost, and work.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a display position adjusting device according to one embodiment. FIG. 1 (A) shows the structure when the rotating mirror is located at the center position of the allowable rotation range, and FIG. , When the rotating mirror is located at the lower limit (upper limit) position of the allowable rotation range, Fig. 1 (C) corresponds to when the rotating mirror is located at the upper limit (lower limit) position of the allowable rotation range. There is.

In FIGS. 1A, 1B, and 1C, the rotary mirror (optical axis variable body) 8 has a rotary shaft 8a (FIG. 8B) similar to the conventional display position adjusting device 7 described above. ), The rotary shaft 8a is rotatably supported by a pair of rotary mirror support portions 13a (FIG. 8B) formed on the base member 13 so as to face each other.

A substantially semicircular first gear 14 is fixed to the rotary mirror 8. The first gear 14 has a rotating shaft 15
Circular second gear 1 supported by the base member 13
6 is meshed. A substantially fan-shaped third gear 17 is fixed to the rotating shaft 15 of the second gear 16. A circular fourth gear 18 is meshed with the third gear 17. The fourth gear 18 is fixed to the output shaft 10a of the motor 10 supported by the base member 13. Motor 1
0 is a reversible motor capable of reversing (either a step motor or a DC motor, but in the present embodiment, a step motor)
Is. Since the rotating means 11 is configured as described above, the rotational force of the rotor of the motor 10 is first transmitted through the output shaft 10a, the fourth gear 18, the third gear 17, and the second gear 16.
The rotation mirror 8 is transmitted by being transmitted to the gear 14, and the optical axis of the display light can be changed.

The third gear 17 is shown in FIGS. 1 (A), (B) and (C).
As shown in, on both sides of the tooth portion that meshes with the fourth gear 18,
The convex portion 23 and the concave portion 2 as the idling lock portion according to the present invention
4 are formed. As shown in FIG. 1 (B), the recess 24 causes the fourth gear 18 to idle, and the power thereof is set to the third gear 17
1C, the convex portion 23 locks the fourth gear 18 and prevents its power from being transmitted to the third gear 17, as shown in FIG. 1 (C). It constitutes the lock part.

The step motor 10 is a known step motor as shown in FIG. 1A, in which a plurality of phases of exciting coils (not shown) are supplied with exciting pulses from a driver 25. However, the control circuit 26 that outputs a control signal to the driver 25 is configured to be able to perform sweep control. Here, the sweep control is to rotate the rotating mirror 8 in the forward direction (tentatively, as will be described later).
The clockwise rotation is the forward rotation. ) That means the fourth gear 18
Is in the idling state shown in FIG. 1 (B), the rotating mirror 8 is automatically rotated in the reverse direction (when the forward direction is determined as described above,
The counterclockwise rotation is reversed. ) After that, when the fourth gear 18 enters the locked state shown in FIG. 1 (C), it means the control content for automatically rotating the rotating mirror 8 forward again.

A spring 22 is arranged between the rotary mirror 8 and the base member 13. This spring 22 not only prevents backlash, but also ensures that the fourth gear 18 meshes with the third gear 17 when the fourth gear 18 is reversed from the idling state, as will be described later. It acts to do.

The display position adjusting device 7 according to the present embodiment.
No limit switches 20 and 21 are provided in the conventional device.

Next, the display position adjusting device 7 according to the present embodiment.
An example of the operation will be described.

First, when the driver turns on the operation switch (not shown) while the rotary mirror 8 is in the state shown in FIG. 1 (A), the output shaft 10a of the step motor 10 is shown in FIG. 1 (B). The forward rotation in the direction indicated by the arrow a is started, and this rotational force is transmitted to the first gear 14 via the fourth gear 18, the third gear 17, and the second gear 16, and the rotary mirror 8 rotates clockwise. .

The teeth of the fourth gear 18 are replaced by the teeth of the third gear 17.
When reaching the concave portion 24, the fourth gear 18 starts to idle. When the rotational force is not transmitted from the fourth gear 18 to the third gear 17 due to the idling of the fourth gear 18, the first gear 14 stops rotating and the rotary mirror 8 is temporarily returned to the state shown in FIG. 1 (B). Retained.

The control circuit 26 instructs the driver 25 to reverse the output shaft 10a of the step motor 10 in the direction of arrow b in FIG. 1 (C) when a predetermined time, for example, 1 second, has elapsed after the fourth gear 18 started idling. Control. Therefore, the fourth gear 1
8 starts reverse rotation when a predetermined time has elapsed after the start of idling. At the start of this reverse rotation, the third gear 17 moves the spring 2
Since the pulling force of 2 always receives the force in the clockwise direction via the rotary mirror 8, the first gear 14, and the second gear 16, the tooth of the fourth gear 18 that started the reverse rotation becomes the tooth of the third gear 17. It can be easily meshed, and switching from idling to reverse rotation can be performed smoothly and reliably.

When the fourth gear 18 starts reverse rotation in this way, the first gear 14 is passed through the third gear 17 and the second gear 16.
Is reversed, and the rotating mirror 8 rotates counterclockwise.

The teeth of the fourth gear 18 are the same as those of the third gear 17.
When reaching the convex portion 23, the fourth gear 18 is locked by the convex portion 23. The locking of the fourth gear 18 prevents the first gear 14 from rotating, and the rotary mirror 8 is temporarily held in the state shown in FIG. 1 (B).

The control circuit 26 controls the driver 25 so as to rotate the output shaft 10a of the step motor 10 in the forward direction when a predetermined time, for example, 1 second has elapsed after the locking of the fourth gear 18 was started. Therefore, the fourth gear 18 starts normal rotation again when a predetermined time has elapsed after the start of locking. In addition, switching from the lock to the forward rotation is performed by locking the teeth of the fourth gear 18
Since the teeth of the gear 17 are in mesh with each other, smooth and reliable operation is achieved.

After that, the above-mentioned operation is repeated while the operation switch is kept on.

As described above, the display position adjusting device 7 according to the present embodiment merely has the concave portion 24 as the idling portion and the convex portion 23 as the lock portion formed on both sides of the tooth portion of the third gear 17. Since the upper limit and the lower limit of the permissible rotation range of the rotary mirror 8 can be set with a simple configuration, the limit switches 20 and 21 can be omitted, thereby reducing the number of parts, reducing the cost, and simplifying the work. be able to.

Further, the display position adjusting device 7 according to the present embodiment.
Has the sweep function as described above, it is not necessary to separately provide a dedicated operation switch for rotating the rotary mirror 8 in the clockwise direction and a dedicated operation switch for rotating the rotary mirror 8 in the counterclockwise direction. Therefore, the driver does not have to perform a complicated operation by operating these operation switches.

2 to 6 show the construction of a display position adjusting device according to another embodiment, respectively.

The display position adjusting device 7 shown in FIG. 2 is characterized in that convex portions 23, 23 as lock portions are formed on both sides of the tooth portion of the fourth gear 18, respectively. With this configuration, the third gear 17 is locked by the convex portions 23, 23 of the fourth gear 18, and the rotary mirror 8
The upper and lower limits of the permissible rotation range can be set.

The display position adjusting device 7 shown in FIG. 3 is characterized in that convex portions 23, 23 as lock portions are formed on both sides of the tooth portion of the second gear 16, respectively. With this configuration, the first gear 14 is locked by the convex portions 23 of the second gear 16, and the rotary mirror 8
The upper and lower limits of the permissible rotation range can be set.

The display position adjusting device 7 shown in FIG. 4 is characterized in that convex portions 23, 23 as lock portions are formed on both sides of the tooth portion of the third gear 17, respectively. With this configuration, the fourth gear 18 is locked by the convex portions 23, 23 of the third gear 17, and the rotary mirror 8
The upper and lower limits of the permissible rotation range can be set.

The display position adjusting device 7 shown in FIG. 5 is characterized in that convex portions 23, 23 as lock portions are formed on both sides of the tooth portion of the first gear 14, respectively. With this configuration, the second gear 16 is locked by the convex portions 23, 23 of the first gear 14, and the rotating mirror 8
The upper and lower limits of the permissible rotation range can be set.

The display position adjusting device 7 shown in FIG. 6 has a convex portion 23 as a lock portion on one end side of the tooth portion of the first gear 14.
On the other end side, a concave portion 24 is formed as an idling portion. With this configuration, the second gear 16 is locked by the convex portion 23 of the first gear 14 and idle by the concave portion 24, and the upper and lower limits of the allowable rotation range of the rotary mirror 8 can be set. .

[Brief description of drawings]

FIG. 1 is a configuration diagram of a display position adjusting device according to an embodiment.

FIG. 2 is a configuration diagram of a display position adjusting device according to another embodiment.

FIG. 3 is a configuration diagram of a display position adjusting device according to still another embodiment.

FIG. 4 is a configuration diagram of a display position adjusting device according to still another embodiment.

FIG. 5 is a configuration diagram of a display position adjusting device according to still another embodiment.

FIG. 6 is a configuration diagram of a display position adjusting device according to still another embodiment.

FIG. 7 is a conceptual diagram of a head-up display incorporating a display position adjusting device.

FIG. 8 is a block diagram of a conventional display position adjusting device.

[Explanation of symbols]

 7 Display Position Adjusting Device 8 Rotating Mirror (Optical Axis Variable Body) 11 Rotating Means 14, 16, 17, 18 Gear 23 Convex Part (Lock Part) 24 Recessed Part (Idling Part)

Claims (2)

[Claims] 1. An optical axis variable body disposed on the optical path of display light, a drive-side gear and a driven-side gear meshing with the driving-side gear, and via the driving-side gear and the driven-side gear. Rotating means for rotating the optical axis variable body by transmitting the driving force by rotating the optical axis variable body, and the optical axis variable body reaches the rotation limit position in one of the drive side gear and the driven side gear. A display position adjusting device for a head-up display, characterized in that an idle lock portion is provided for idling or locking the drive side gear at the time. 2. The head-up display according to claim 1, wherein the variable body rotating means is provided with a sweep function for reversing the drive-side gear after the drive-side gear starts to idle or lock. Display position adjustment device.