JPH04101992A - Elevator door control device - Google Patents

Abstract

PURPOSE:To prevent wrong operation by providing a second amplifier with an amplification factor lower than that of a first amplifier connected to an infrared ray sensor for detecting heat generated by passengers, and cutting off the output of the first amplifier when the output of the second amplifier reaches a specified level. CONSTITUTION:There is provided an amplifier with a low frequency characteristic and an amplification factor lower than that of an amplifier 2 connected to an infrared ray sensor 1. This amplifier 4 is connected to a level detector 5 so as to detect the level of the output 4a of the amplifier 4. When the output 2a of the amplifier 2 becomes more than the specified value in this constitution, a door opening command signal is outputted from a detection level judging circuit 3. On the other hand, when the level of the output 4a of the amplifier 4 becomes more than the specified value, the level detector 5 is operated so as to operate the detection level judging circuit 3 to the cutoff side, thus impeding the generation of a door opening command. Wrong operation caused by the infrared ray output of a heater or the like can be thereby prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a device for controlling the opening and closing of elevator doors using an infrared sensor.

[Prior Art] Conventionally, as shown in, for example, Japanese Utility Model Publication No. 56-47186, a light beam is passed through the entrance and exit of an elevator, and when the light beam is blocked by a passenger or the like, the door is prevented from closing and the door is closed. Measures are being taken to prevent collisions with passengers and others.

Furthermore, as shown in FIG. 3, a system has been proposed that uses an infrared sensor to detect passengers and control the door.

In the figure, (1) is an infrared sensor that detects the heat generated by passengers, (2) is an amplifier connected to the infrared sensor (1),
(3) is a detection level determination circuit connected to the amplifier (2), which monitors the output level of the amplifier (2) in accordance with the position of the door, and generates a door open command signal when the output level is high.

A conventional elevator door control device is constructed as described above, and when the presence of a passenger is detected by the infrared sensor (1), the infrared sensor (1) emits an output, which is amplified by the amplifier (2). . Then, when the level reaches a predetermined value or higher,
A door opening command signal is output from the detection level determination circuit (3), and the closed door is reversed and opened to prevent passengers from colliding with the door.

The infrared sensor (1) is excellent in that it can efficiently detect a human body. However, if there is a heat source other than the human body within the detection range, such as a heater or an electric advertising stand, the door opening command signal will continue to be output, and the door will remain open.

Particularly in the event of a fire, if the door continues to open, there is an increased chance that passengers will be engulfed in smoke. Therefore, in order to prevent this, if the output of the infrared sensor (1) continues for a certain period of time or more, the output is cut off and the door is closed.

[Problem fL to be solved by the invention] In the conventional elevator door control device as described above,
The infrared sensor (1) detects a passenger and opens the door, and if the output of the infrared sensor (1) continues for a certain period of time, the output is cut off, so the door can be opened using a heat source other than the human body, and the operation efficiency is improved. There is a problem that it decreases.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide an elevator door control device that can prevent the door from malfunctioning and opening due to heat sources other than the human body.

[Means for Solving the Problems] An elevator door control device according to the present invention includes a first amplifier connected to an infrared sensor to control the door, and an amplification factor lower than that of the first amplifier. A second amplifier is provided, and when the output of the second amplifier exceeds a predetermined level, the output of the first amplifier is cut off.

[Function] In this invention, the output of the first amplifier is cut off when the output of the second amplifier, which has a lower amplification factor than the first amplifier that controls one house, exceeds a predetermined level. , the first amplifier becomes insensitive when it detects infrared rays that are stronger than the human body.

[Embodiment] Fig. 1 and Fig. 2 are diagrams showing an embodiment of the present invention. Fig. 1 is a block circuit diagram, and Fig. 2 is an output waveform diagram. Parts similar to those of the conventional device are designated by the same reference numerals. Indicated by

In the figure, (2a) is the output of the amplifier (2), (4) is the amplifier connected to the infrared sensor (1) and has a lower amplification factor and lower frequency characteristics than the amplifier (2), and (4a) is its output. ,(
5) is a level detector connected to the amplifier (4).

Next, the operation of this embodiment will be explained with reference to FIG.

As described above, when the output (2a) of the amplifier (2) exceeds a predetermined value, the detection level determination circuit (3) outputs a door open command signal. Then, the output (4) of the amplifier (4)
When a) becomes equal to or higher than a predetermined level, the level detector (5) operates, and the detection level determination circuit (3) is operated to the cut-off side to prevent generation of the one door open command signal.

In other words, Figure 2 (a) shows the output (2a) (4a) when a strong infrared object such as a heater is detected, and Figure 2 (b) shows the output (2a) (4a) when a human body is detected. )
It shows the status of. In the case of Fig. 2 (a), the output of the infrared sensor (1) caused by a heater or the like is large, so even the output (4a) of the amplifier (4) with a low amplification factor is saturated, and the output (4a) of the amplifier (4) with a high amplification factor is saturated. ) is blocked by the detection level determination circuit (3), and no door opening command signal is generated.

In addition, in the case of Fig. 2(b), since the output of the infrared sensor (1) due to the human body is small, the output of the amplifier (4) (4a
) is also small, and the level detector (5) does not operate.

Therefore, the output (2a) of the amplifier (2) operates the detection level determination circuit (3) and generates a door open command signal.

[Effects of the Invention] As explained above, in this invention, when the output of the second amplification factor, which has a lower amplification factor than the first amplifier that controls the door, exceeds a predetermined level, the output of the first amplifier is cut off. As a result, when infrared rays from sources other than the human body are detected, the first amplifier becomes insensitive, preventing the door from opening due to heat sources other than the human body and reducing operational efficiency, and ensuring safety even in the event of a fire. There is.

[Brief Description of the Drawings] Fig. 1 is a block circuit diagram showing an elevator door control device according to the present invention, Fig. 2 is an output waveform diagram of Fig. 1, and Fig. 3 is a conventional elevator door control device. FIG. 2 is a block circuit diagram showing a control device. In the figure, (1) is an infrared sensor, (2) is a first amplifier,
(2a) is the same left output, (4) is the second amplifier, (4a
) is the same output as on the left, (5) is a level detector, and (3) is a detection level determination circuit. Note that the same reference numerals in the figures indicate the same or equivalent parts. ■ 1st level & exit 1st diagram (d) (b 1st < /

Claims (1)

[Claims] In a device that includes an infrared sensor that detects heat generated by a passenger and controls a door by the output of a first amplifier connected to the infrared sensor, the first amplifier has an amplification factor lower than that of the first amplifier. 1. A control device for an elevator door, comprising: a second amplifier; and a detection level determination circuit that cuts off the output of the first amplifier when the output of the second amplifier exceeds a predetermined level.