JPH0235591A - Function diagnosing system for crime preventing sensor - Google Patents

Abstract

PURPOSE:To execute a detecting operation even while a sensor is diagnosed by making the output of the sensor caused by the heating of a heater while the sensor is diagnosed lower than an object detecting level. CONSTITUTION:A crime preventing sensor A is equipped with a sensor 1, a signal processing circuit 2, and a heater 3 to be heated when the sensor 1 is diagnosed. An abnormality detecting level in the signal processing circuit 2 when the sensor 1 is diagnosed is previously set lower than the detecting level for detecting a human organism, etc. When a heat ray from a human organism B, etc., is sensed by the sensor 1 during a period in which the sensor 1 is diagnosed, the output, which is the result of adding the heating value of the heat ray from the human organism B, etc., to the heating value from a motor 3, can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a security sensor equipped with a sensor diagnostic function to check whether the sensor is operating normally.

[Prior Art 1] Some crime prevention detectors are equipped with a sensor diagnostic function to check whether the sensor is operating normally.

This security sensor is equipped with a heater that applies heat to the sensor, and it is diagnosed whether the sensor is normal or not based on the output of the sensor when the heater heats the sensor. However, with conventional security detectors of this type, it takes about 3 seconds for sensor diagnosis, and the sensor cannot perform detection operations such as detecting objects, and each time sensor diagnosis is performed, the sensor It is undesirable for a crime prevention system to be in an undetected state.

[Problems to be Solved by the Invention J The present invention has been made in view of the above-mentioned points, and its purpose is to provide a function of a security sensor that can perform a detection operation even during diagnosis of the sensor. The objective is to provide a diagnostic method.

Means for Solving 1 Problem] In order to achieve the above object, the present invention lowers the output of the sensor due to heating of the heater during sensor diagnosis to be lower than the object detection level.

(Function) As described above, the present invention lowers the output of the sensor due to heating of the heater during sensor diagnosis to a level lower than the object detection level, so that heat from an external heat source such as a human body can be detected even during the sensor diagnosis period. This is to ensure that this sensor diagnosis period does not become a non-detection period.

(Example) An embodiment of the present invention is shown in FIGS. 1 to 3.

As shown in Fig. 1, this security sensor A includes a sensor 1 that detects heat rays emitted by a human body B, etc., and outputs a sensing signal proportional to the size of the heat rays, and a sensor 1 that detects heat rays emitted by a human body B, etc. Decide whether to issue an alarm and sense the result 4
It includes a signal processing circuit 2 that outputs to the line section, and a heater 3 that is heated when diagnosing the sensor 1. In addition,
Heating control of the heater 3 is performed by the signal processing circuit 3, and the signal processing circuit 3 determines the sensor 1 based on the output of the sensor 1 at this time.
determine whether it is normal. Note that this diagnostic result is also output to the sensor line α.

The abnormality detection level Vck when diagnosing the sensor 1 of the signal processing circuit 2 of the security sensor A of this embodiment is lower than the detection level Vth for detecting a human body, etc., as shown in FIG. When heat rays from human body B etc. are detected by sensor 1 during this sensor diagnosis period, the output is the sum of the heat amount from the heater 3 and the heat rays from human body B etc. as shown in FIG. becomes. Therefore, in this example,
The signal processing circuit 2 calculates an increase in the output of the sensor 1 during heating by the heater 3 shown in FIG. 2 (4), and increases the detection level by vth' from Vth during the sensor diagnosis period.

In other words, the detection level is increased by the amount of increase in the output of the sensor 1 during heating by the heater 3. Therefore, even during this sensor diagnosis period, detection operations such as human body detection can be performed as in the normal state.

By the way, in the above-mentioned circuit, the heater 3 is heated for a certain period of time to determine whether or not a sensing signal of - room or higher is output from the sensor 1, but by changing the heating temperature or heating time of the heater 3, the sensor 1 operation or signal processing circuit 2
By diagnosing whether the signal processing operation of the By checking whether the output corresponds to the heating state in step 3, it is possible to more accurately diagnose whether the sensor is operating normally. Also, as mentioned above, by varying the heating temperature of the heater 3 in multiple stages, or by varying the heating time in multiple stages, it is possible to check whether the signal processing circuit 2 outputs an alarm normally or not. It is possible to check various judgment processes, such as whether or not environmental signals can be judged.

Effect of the invention 1 As described above, the present invention lowers the sensor output due to heating of the heater during sensor diagnosis to a level lower than the object detection level, so that heat from an external heat source such as a human body can be detected even during sensor diagnosis. This eliminates the non-detection period of the security detector, which has the effect of increasing the reliability of the security system.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIGS. 2 and 3 are explanatory diagrams of the same operation. A is a security sensor, B is a human body, 1 is a sensor, 2 is a signal processing circuit, and 3 is a heater. Agent Patent attorney Ishi 1) Naga Nanashi to one featherg υYame to Uchiha

Claims (2)

[Claims] (1) A sensor that detects heat from an external heat source such as a human body and outputs a detection signal of a size corresponding to the heat, and signal processing that determines whether to output an alarm based on the output of this sensor. The sensor is characterized by comprising a circuit and a heater that is heated when performing a sensor diagnosis to check whether the sensor is operating normally, and the output of the sensor due to heating of the heater during the sensor diagnosis is lower than the object detection level. Functional diagnosis method for security detectors. (2) A functional diagnosis of a crime prevention sensor characterized by checking whether the sensing operation of the sensor and the judgment operation of the signal processing circuit are performed normally by varying the heating temperature and heating time of the heater as appropriate. method.