JPH0712968Y2 - Vehicle display - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a vehicle display device configured to project a display image through a lens system. More specifically, the sunlight is directly incident through the lens system. The present invention relates to a vehicle display device used in such an environment.

[Conventional technology]

Conventionally, as this type of vehicle display device, a device called a head-up display having the configuration shown in FIG. 4 has been proposed.

In the figure, a head-up display device 2 provided near a windshield 1 of a vehicle includes a lens system 2a and a display device 2b, and is housed in a dashboard (not shown). The lens system 2a is provided near the dashboard, and a display device 2b including a liquid crystal display (LCD) cell or the like is provided on the surface facing the dashboard.

A shutter device 3 is provided between the windshield 1 and the lens system 2a on the optical axis of the lens system 2a.
In the shutter device 3, strong external light such as sunlight enters through the lens system 2a and irradiates the display device 2b provided at a substantially focal position of the lens system 2a, so that the display device 2b is heated. The shutter plate 3a is for preventing destruction, and the solenoid 3b for driving the shutter plate 3a in the opening direction by its urging.
A spring 3c for holding the shutter plate 3a in a closed state when the solenoid 3b is not energized, and a solenoid 3b.
And a drive circuit 3d for driving the. Note that 3e is a stopper for positioning the shutter plate 3a at the open / close position.

In the configuration shown in the figure, the display image of the display device 2b is projected on the surface of the windshield 1 which functions as a reflecting member via the lens system 2a when the shutter plate 3a is opened by the bias of the solenoid 3b. Windshield 1
Is reflected on the surface of. Therefore, when the reflected light reaches the eyes E of the driver, the driver can see the displayed image as a virtual image in front of the windshield 1 so as to overlap the external scenery.

When an ignition switch (not shown) is turned off, the drive circuit 3d releases the energization of the solenoid 3b which has been energized up to that point. Solenoid 3d
When the bias of is released, the shutter plate 3a
Since it is closed by the biasing force of the display device, even if sunlight enters the vehicle interior through the windshield 1 during parking or the like, it does not enter the interior through the lens system 2a of the head-up display device 2 and the display device It is possible to reliably prevent the thermal destruction of 2b.

[Problems to be solved by the device]

However, in the configuration of the conventional device described above, the shutter plate
Since the shutter plate 3a must be moved against the spring 3c to change the closed state from the closed state of 3a, a solenoid 3b having a large driving force must be used. Further, in order to keep the shutter plate 3a open during the display, a large current has to be passed through the solenoid 3b during that time, which causes a problem that a large amount of heat is generated.

Therefore, in view of the above-mentioned conventional problems, the present invention can maintain a displayable state without causing heat generation, and moreover, can securely close the shutter plate when the ignition switch is turned off. The challenge is to provide.

[Means for Solving the Problems]

In order to solve the above problems, a vehicular display device according to the present invention includes a lens system and a display device, projects a display image of the display device onto a reflecting member through the lens system, and the driver reflects the reflected image. And a motor for driving the shutter means, wherein the shutter means prevents external light from entering the interior through the lens system when the ignition switch is turned off. A detection means for detecting a state of the shutter means and an off detection means for detecting an off state of an ignition switch, and the detection means detects that the shutter means does not block the incidence of external light. At this time, the motor is driven in response to the detection of the turning-off of the ignition switch by the off detection means to operate the shutter means. It is characterized in that to drive the state of blocking light.

[Action]

In the above configuration, since the shutter means for preventing the outside light from entering through the lens system is driven by the motor, it is possible to drive the shutter means to an arbitrary state by changing the rotation direction of the motor. The shutter means can be held in a predetermined state by stopping the driving. Moreover, when the detection means detects that the shutter means does not block the incidence of external light, the motor is driven in response to the detection of the ignition switch being turned off by the off detection means to block the shutter means from external light. The display device is prevented from being thermally destroyed by strong external light being input to the inside through the lens system when the vehicle is parked.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of a vehicle display device according to the present invention, in which the same parts as those described above with reference to FIG. 4 are designated by the same reference numerals.

In the figure, the shutter plate 3a of the shutter device 3 is configured to be opened and closed by a motor 3f, and limit switches 3g and 3h for detecting the open / closed state of the shutter plate 3a are provided.

When the display operation switch (not shown) is operated, the motor 3f is driven in the forward and reverse directions in accordance with the states of the limit switches 3g and 3h to open and close the shutter plate 3a in the closed state and the open state, respectively. When the ignition switch is turned off while the shutter plate 3a is in the open state, the shutter plate 3a is driven in the normal direction to close the shutter plate 3a.

FIG. 2 is a block diagram showing the electric circuit configuration of the shutter device 3 described above. In FIG. 2, 3i is a control circuit, and the limit switches 3g and 3h are input to the circuit.
Besides, the outputs of the display operation switch 3j and the ignition switch (IG) off detection circuit 3l are connected. The control circuit 3i outputs a motor forward rotation control signal and a reverse rotation control signal to its output, and inputs this to the motor drive circuit 3l. The motor drive circuit 3l supplies a drive current for driving the motor 3f in the normal and reverse directions to the motor 3f while the normal and reverse control signals are input to the input. The motor drive circuit 3l
Power is always supplied from the on-board battery + B. The IG off detection circuit 3k is an ignition switch IG.
Detects that the is turned off from the on state and outputs a signal to its output.

In the above configuration, when the display operation switch 3j is turned on while the ignition switch IG is turned on, the control circuit 3i reads the state of the limit switches 3g and 3h, and the shutter plate It is detected whether 3a is open or closed, and the forward rotation control signal or the reverse rotation control signal is output according to the detection result.

That is, when the limit switches 3g and 3h are opened and closed, the shutter plate 3a is in the open state, and therefore the control circuit 3i controls the forward rotation to close the shutter plate 3a in response to the turning on of the display operation switch 3j. Output a signal. Also, when the limit switches 3g and 3k are closed and open,
Since the shutter plate 3a is in the closed state, the control circuit 3i outputs a reverse rotation control signal to open the shutter plate 3a. In response to the input of these forward rotation and reverse rotation control signals, the motor drive circuit 3l supplies a drive current to the motor 3f to drive forward rotation and reverse rotation. The normal rotation and reverse rotation drive of the motor 3f by the motor drive circuit 3k is performed while the normal rotation and reverse rotation control signals are input.

When the shutter plate 3a is driven by the motor 3f, both limit switches 3g and 3h are turned off, but when the shutter plate 3a is opened to closed or closed to open, the limit switch 3h or 3g is turned from on to on. . Therefore, the control circuit
3i continues to monitor the state of the limit switches 3g and 3h, and when the above-mentioned, that is, the change of the limit switch 3h or 3g from OFF to ON is detected, the forward rotation control signal or the reverse rotation signal output up to that time is detected. The control signal is lost, and the driving of the motor 3f by the motor drive circuit 3l is stopped. Therefore, thereafter, the closed state or the open state of the shutter plate 3a is maintained.

Then, when the ignition switch IG is turned off while the shutter plate 3a is in the open state, the ignition switch off detection circuit 3k detects this, outputs a signal to its output, and inputs it to the control circuit 3i. Control circuit accordingly
3i outputs a normal rotation control signal and inputs it to the motor drive circuit 3l. The motor drive circuit 3l to which the normal rotation control signal is input drives the motor 3f in the normal direction to close the shutter plate 3a. When the shutter plate 3a is closed and the limit switch 3h is turned on from off, the normal rotation control signal is not output, the normal rotation of the motor 3f is stopped, and the shutter plate 3a is kept closed thereafter.

Details of the above-described operation will be described below with reference to the flowchart of FIG.

The control circuit 3i starts its operation when its power is turned on,
In the first step S1, it is determined whether or not the display operation switch 3j is on. When the display operation switch 3j is turned on and the determination in step S1 is YES, the process proceeds to step S2, where it is determined which of the limit switches 3g and 3h is on. When the limit switch 3g is turned on, the process proceeds to step S3, at which the output of the normal rotation control signal is turned on and the motor 3f is normally rotated to drive the shutter plate 3a in the closing direction. After that, the process proceeds to step S4, where it is determined whether the limit switch 3h is turned on from off,
Wait until this judgment becomes YES. When the determination in step S4 is YES, the process proceeds to step S5, where the output of the normal rotation control signal is turned off, and then the process returns to step S1.

When it is determined in step S2 that the limit switch 3h is turned on, the process proceeds to step S6, where the output of the reverse rotation control signal is turned on and the motor 3f is rotated in the reverse direction to release the shutter plate.
Drive 3a in the opening direction. After that, the process proceeds to step S7, where it is determined whether or not the limit switch 3g is turned on, and the process waits until this determination becomes YES. When the determination in step S7 is YES, step S8
Then, the output of the reverse rotation control signal is turned off, and the process returns to step S1.

If the determination in step S2 is NO, that is, the display operation switch
When 3j is not turned on, the process proceeds to step S9,
Here, it is determined whether or not the ignition switch is turned off based on the presence / absence of a signal input from the IG off detection circuit 3k. When the determination in step S9 is NO, step S1
Returning to, when the determination is YES, the process proceeds to step S10, where it is determined whether the limit switch 3g is turned on to determine whether the shutter plate 3a is opened. When the determination in step S10 is NO, the shutter plate 3a is determined to be closed, and the process returns to step S1 without doing any work,
If the determination is YES and the shutter plate 3a is open, the process proceeds to step S3 to close the shutter plate 3a, and the shutter plate 3a is closed.

The control circuit 3i can be configured by using a CPU to control the motor drive circuit.

〔effect〕

As described above, according to the present invention, since the motor is used instead of the solenoid as the drive source for driving the shutter means, the shutter means can be driven to any state by changing the rotation direction of the motor. The shutter means can be held in a predetermined state by stopping its driving, and a displayable state can be maintained without heat generation.

Moreover, since the shutter means is automatically made to block the external light when the ignition switch is turned off, the external light is input inside through the lens system during parking and the display device is thermally destroyed. Will be prevented.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a vehicular display device according to the present invention, FIG. 2 is a block diagram showing an electric circuit configuration of the device shown in FIG. 1, and FIG. 3 is a diagram showing the control circuit shown in FIG. FIG. 4 is a flowchart showing the work performed by the CPU, and FIG. 4 is a diagram showing an example of a conventional device. 1 ... Windshield (reflection member), 2a ... Lens system,
2b …… Display device, 3a …… Shutter plate (shutter means), 3f …… Motor, 3g, 3h …… Limit switch (detection means), 3k …… IG off detection circuit (off detection means), IG …… Ignition switch.

Claims (1)

[Scope of utility model registration request] 1. A lens system and a display device are provided, a display image of the display device is projected onto a reflecting member via the lens system so that the driver can visually recognize the reflected image, and when the ignition switch is turned off. A vehicle display device configured to prevent external light from entering the interior through the lens system by a shutter means, a motor for driving the shutter means, a detection means for detecting a state of the shutter means, and an ignition switch. Off detection means for detecting the off state of the ignition switch, and when the detection means detects that the shutter means does not block the incidence of outside light, the off detection means detects the off state of the ignition switch. Drive the motor to drive the shutter means to block external light. The display device for a vehicle.