JPH05310077A - Dimmer for vehicle - Google Patents

Abstract

PURPOSE:To prevent mis-reading from an indicator due to delay of response of a driver's eyes caused immediately after a vehicle comes into and out of a tunnel. CONSTITUTION:A control device 2 determines a brightness of an indicator 4 in a driver's seat by the signal from an illuminance detector sensor 1. When the illuminance becomes small as in the case that a vehicle comes in a tunnel from the outside of it, the control device increases a current value to increase the brightness of the indicator 4 and, after a specified time has been collapsed, decreases the current value so that the brightness according to the illuminance can be attained. On the other hand, when the illuminance becomes large as in the case that the vehicle comes out of the tunnel from the inside of it, the current value is increased to decrease the brightness of the indicator 4 and, after a specified time has been collapsed, the current value is increased so that the brightness according to the illuminance can be attained. The specified time above means a time by which the eyes of a driver are accustomed to the surrounding illuminance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimming function of a display used in a vehicle, and more particularly to a dimming device suitable for a driver's cab which requires automatic brightness adjustment according to changes in ambient illuminance.

[0002]

2. Description of the Related Art There are various kinds of optical indicators on the driver's cab of vehicles, especially railway vehicles, but their brightness is constant.

[0003]

When the brightness of the surroundings greatly changes, such as when a vehicle enters or leaves a tunnel, if the brightness of the cab optical display is constant, The optical display is difficult to read and dangerous.

It is an object of the present invention to allow the brightness of a display to change in response to ambient light intensity.

[0005]

As a control device for setting the brightness of the display according to a signal of a sensor for detecting the illuminance around the display, the brightness of the display is controlled when the illuminance becomes small. Increase the current value to increase, and after a predetermined time, decrease the current value so that the brightness corresponds to the illuminance, and conversely, if the illuminance increases, decrease the brightness of the display unit. This can be achieved by increasing the value and increasing the current value so that the brightness corresponds to the illuminance after a predetermined time.

[0006]

The brightness is set to be too high or too low until the human eyes reach the illuminance of the surroundings. Therefore, it is possible to prevent the display from being read by the driver when the eyes are responsive.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be explained. 1 is a sensor that detects the illuminance around the display, 2 is a control device that reads a signal from the sensor, converts it into a current having characteristics, and stores a pattern of characteristics,
3 is a transistor whose base current is the current converted by the control device 2, 4 is an indicator installed on the driver's cab of the vehicle, and 5 is a manual rotary switch for changing the characteristic pattern when the control device 2 converts the current. is there.

The control device 2 controls the amount of change in illuminance as shown in FIG.
The current value is changed as shown in. That is, when the illuminance does not change (x = 0) as when the vehicle is traveling inside or outside the tunnel, the current value is not changed (the brightness is not changed). When the illuminance becomes small (x> 0), such as when entering the tunnel from outside the tunnel, the current value is increased to increase the brightness of the display, and after a predetermined time, the brightness corresponding to the illuminance is obtained. The current value is reduced so that The current value increased within the predetermined time is a predetermined value and is added to the current current value. On the other hand, when the illuminance becomes large (x <0), such as when exiting from inside the tunnel, the current value is increased so as to reduce the brightness of the display, and after a predetermined time, the illuminance is adjusted. The current value is increased so that the brightness becomes the specified brightness.
The current value to be reduced within the predetermined time is a predetermined value and is subtracted from the current current value. The predetermined time is the time required for the driver's eyes to reach the ambient illuminance. The predetermined value is a current value for obtaining an easily visible brightness within the predetermined time. The rotary switch 6 changes the combination of the predetermined time and the predetermined value.

With the above configuration, when the vehicle enters or leaves the tunnel, as shown in FIG.
The brightness of the display changes. For this reason, the driver can easily see the display and prevent it from being read.

In the above-described embodiment, whether the vehicle enters or leaves the tunnel is detected by the illuminance. However, a device for detecting the position with respect to the tunnel is provided in the vehicle, and the brightness within the predetermined time is changed by the signal of this device. May be. The detection device can be configured, for example, by providing strikers at the entrance and exit of the tunnel and providing a vehicle with a sensor for detecting the striker.

[0011]

According to the present invention, since the brightness is determined in response to the characteristics of the human eye, the influence of glare on driving and the oversight of ON / OFF of the display due to darkness can be minimized. It is effective.

[Brief description of drawings]

FIG. 1 is a dimming circuit diagram of an indicator light dimming device according to an embodiment of the present invention.

FIG. 2 is a conversion flowchart in the control device provided in the dimming circuit.

FIG. 3 is a graph showing a change in illuminance of a display device with respect to a change in ambient illuminance.

[Explanation of symbols]

1 ... Illuminance detection sensor, 2 ... Control device, 3 ... Transistor, 4 ... Indicator, 5 ... Rotary switch.

Claims (1)

[Claims] 1. A driver's cab display of a vehicle, a sensor for detecting illuminance around the display, and a controller for setting the brightness of the display according to a signal from the sensor. When the illuminance is low, the current value is increased so that the brightness of the display is increased, and after a predetermined time, the current value is decreased so that the brightness corresponds to the illuminance, and conversely, the illuminance is increased. In the case of lighting, the current value is increased so as to reduce the brightness of the display, and after a predetermined time, the current value is increased so as to reach the brightness corresponding to the illuminance. apparatus.