JP2000132118A - Elevator display device - Google Patents

Abstract

(57) [Summary] [Problem] A dot type L for displaying a car position and a driving direction provided at each landing of an elevator or a car.
Deterioration of the luminance of the display characters of the ED display over time can be measured for each dot L
It is possible to automatically correct each individual dot LED based on the lighting time of the ED. Each dot LED is determined by a count value of a timer.
Is calculated, and the current luminance of each dot LED is calculated from the luminance change due to aging of each dot LED in the dot type LED display element, and the dot type LED display is driven based on the calculation result. By changing the pulse width, each dot L
The luminance of each ED is automatically corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying operation information of an elevator, and more particularly to a display device for automatically displaying the aging deterioration of the brightness of each dot LED of a dot type LED display by the lighting time of each dot LED. The present invention relates to an elevator display capable of performing correction.

[0002]

2. Description of the Related Art In a dot-type LED display, in order to light a light emitting element by time division control, a driving method of passing a pulse current intermittently with a fixed time width is used for the light emitting element.

In such a driving method, a current is intermittently supplied to the light emitting element, so that the light emitting state of the light emitting element blinks due to the intermittent current, but is recognized by the naked eye as apparently continuous light emission due to an afterimage phenomenon.

For example, in the technique disclosed in Japanese Patent Application Laid-Open No. 63-315479, since the pulse width and the LED drive current are both constant, the brightness of the displayed characters is also constant.

[0005]

In the above prior art, since the pulse width for driving the display and the LED drive current are both constant, it is difficult to change the brightness of the displayed characters.

An object of the present invention is to provide a configuration in which the luminance of a display character can be changed individually for each dot LED.

Another object of the present invention is to automatically correct the aging of each dot LED individually based on the lighting time of each dot LED, so that even when the luminance decreases due to the aging of the LED, a stable character display with little luminance variation can be obtained. It is to provide a possible elevator display device.

[0008]

The object of the present invention is to provide a structure in which the pulse width can be changed while the driving current of the LED remains constant and the pulse width is changed according to the lighting time of each dot LED. Change the brightness.

That is, in the display device of the elevator, the aging deterioration of the luminance of each dot LED is automatically corrected based on the lighting time of each dot LED. As a result, even if the brightness of the displayed characters does not decrease due to the deterioration of the LEDs over time, it is possible to realize an elevator display device in which the displayed characters are easy to see.

[0010]

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

FIG. 1 shows the overall structure of the elevator. When the hall button 19 is pressed, the information is transmitted to the control panel 1 via the transmission line 5. Upon receiving the elevator call information, the control panel 1 operates in response to the floor where the elevator call has occurred. Further, the dot type LED display 7 displays the current position of the car 3.

FIG. 2 shows a control circuit configuration of the dot type LED display. When the floor display data sent through the transmission line is input to the communication circuit 17, the MPU 11 is based on the data.
Displays characters on the floor indicator light and direction light 14 which are dot type LED displays. When the Hall button 19 is pressed, the signal level is converted by the input circuit 18 and M
It is input to PU11. Then, the MPU 11 is configured to transmit the information of the hole button 19 to the transmission path via the communication circuit 17.

The timer 15 always counts at the reference time. The MPU 11 calculates the difference between the count value of the timer 15 at the time of switching the display contents of the floor indicator light and the direction light 14 and the time of the next display content switching. Then, based on the result, the result is added to the data in the storage area of the memory 30 corresponding to each of the lit dot LEDs. Thereafter, this operation is repeated. The memory 30 retains the stored contents even when the power supply is cut off.

FIG. 3 shows the appearance of a dot-type LED display element. A plurality of display elements 14a are arranged to form a floor indicator light and a direction light 14.

The operation of displaying the floor indicator light and the direction light 14 is performed by the common select signal 2 from the MPU 11.
1 to 23, a plurality of segment signals 25 are output, and an output permission signal 24 is output to turn on one row in which the common select signal of the floor indicator light and the direction light 14 is selected. This operation displays all the characters while switching the lines sequentially in a time-division manner.

FIG. 4 shows common select signals 21 to 23,
Segment signals 25a to 25e and output permission signal 24
The timing of FIG. The LED lighting timing is determined by the pulse width t of each of the segment signals 25a to 25e.
Is the same as

FIG. 5 shows an example of luminance change due to aging of the dot-type LED display element 14a. The luminance of the display character of the dot-type LED display element 14a at the start of operation is set to 100% (initial value). In this case, it can be seen that the luminance changes linearly to 50% of the initial value after 10 years.

Each dot LED stored in the memory 30
With reference to the lighting time of, the current luminance of each dot LED can be calculated based on the luminance change (FIG. 5) due to the aging deterioration of the dot type LED element. From this result, the pulse width t of the segment signals 25a to 25e is increased by an amount corresponding to the deterioration of the luminance of the display character to increase the luminance of the display character.

Here, if the pulse width t of the segment signals 25a to 25e is made longer, the brightness of the dot LED becomes brighter. Conversely, when the pulse width t of the segment signals 25a to 25e is shortened, the brightness of the dot LED becomes dark.

For example, referring to FIGS. 3 and 4,
When the pulse width of the segment signal 25a in the second row is shortened to t1 and the segment signal 25e in the fourth row is lengthened to t2 at the control timing of the dot type LED display in FIG. 4, as shown in FIG. Dot LED, that is, the dot LED of the segment signal 25a in the second row
Becomes dark, and the dot L of the segment signal 25e in the fourth row
ED becomes bright.

According to this embodiment, the aging of each dot LED can be automatically corrected by the lighting time of each dot LED, and a display device which is easy to see can be realized.

[0022]

As described above, according to the present embodiment, since the aging deterioration of the brightness of the display character is automatically corrected by the lighting time of each dot LED individually, the display at the start of operation can be performed even if the system is operated for a long time. Luminance of characters can be ensured, and a display device in which displayed characters are easy to see can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an elevator according to the present invention.

FIG. 2 is a control circuit configuration of the dot type LED display of the present invention.

FIG. 3 is a front view showing the appearance of a dot type LED display element of the present invention.

FIG. 4 is a control timing chart of the dot type LED display of the present invention.

FIG. 5 is a characteristic diagram showing a luminance change due to aging of the dot type LED display element of the present invention.

[Explanation of symbols]

1 ... control panel, 2 ... induction motor, 3 ... basket, 4
... balance weight, 5 ... transmission line, 7 ... dot type LED display, 11 ... MPU, 12 ... common driver circuit, 13 ...
Segment driver circuit, 14 floor indicator and direction light, 14a dot-type LED element, 15 timer, 17
... communication circuit, 18 ... input circuit, 19 ... hole button, 2
1 to 23: common select signal, 24: output permission signal,
25: segment signal, 25a: segment signal a, 2
5b ... segment signal b, 25c ... segment signal c,
25d: segment signal d, 30e: memory.

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Riki Komatsu 232 Horiguchi, Hitachinaka-shi, Ibaraki Pref. System Plaza Katsuta Hitachi Mito Engineering Co., Ltd. F-term (reference) AA67 AA87 BA36 CF21 CG10 CG42 CH07 CH08 CH22 CM07 5G435 AA01 BB04 CC06 CC09 LL18

Claims (1)

[Claims] 1. A dot type LED display provided in each elevator hall or in a car for displaying a car position and a driving direction, the aging of each dot LED brightness due to the lighting time of each dot LED individually. A display device for an elevator, comprising: means for automatically correcting the following.