JPH0453588Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a semi-sensitive traffic signal control vehicle sensing device installed at an intersection that controls traffic lights using a semi-sensitive control method.

Conventional technology Traditionally, semi-sensitive traffic control systems have been used to control traffic lights installed at intersections where a wide main road where a green light is always displayed and a narrow secondary road where a red light is always displayed intersect. Various types of vehicle sensing devices are known for sensing roadside objects (hereinafter referred to as vehicles), such as ultrasonic vehicle sensing devices and optical vehicle sensing devices that utilize the Doppler effect.

Problems to be Solved by the Invention However, although the ultrasonic vehicle sensing device using the Doppler effect is suitable for moving vehicles, it is not suitable for stationary vehicles. On the other hand, optical sensing devices can detect stopped vehicles;
The directivity is sharp, the detection area is narrow, the range of stop positions that can be detected is limited, and there are unstable factors, and the influence of rain, snow, etc. is large, so
Vehicle detection cannot be performed accurately, there are installation restrictions to protect the sensor from direct sunlight, and furthermore, maintenance and inspection such as cleaning of the lens surface is required. It was hot. In addition, conventional vehicle sensing devices tend to be particularly difficult to detect small two-wheeled vehicles.

The present invention has been made in view of the above-mentioned problems, and particularly aims to provide a semi-sensitive traffic signal control vehicle sensing device suitable for detecting two-wheeled vehicles.

Means for Solving the Problems According to the present invention, the above problems can be solved by using a semi-sensitive traffic signal control vehicle sensing device that emits ultrasonic waves and obtains a reflection from the sensed object within a certain period of time. The solution is to include a sonic sensor and a push button switch for a two-wheeled vehicle, and to output an OR output when the ultrasonic sensor detects a sensed object or when the push button switch is depressed. be done.

Embodiments Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

FIG. 1 is a block diagram showing an embodiment of a vehicle sensing device for semi-sensitive traffic signal control according to the present invention, in which 1 is a reflector, 2 is a push button switch, and 3 is a display.

The vehicle sensing device for semi-sensitive traffic signal control uses a semi-sensitive control method (in contrast to periodic control in which signals are controlled according to a fixed time and order), the vehicle sensing device detects the traffic request of a vehicle or a pedestrian and controls the traffic signal accordingly. Of the sensitive controls that change the method and time of signal display, this refers to a control method in which vehicle detectors are installed only on the secondary road side.The control method that is also sensitive to traffic on the main road side is called fully sensitive control. ) is installed on the side of the road on the side of the secondary road at an intersection where a wide main road with a constant green signal intersects with a narrow secondary road with a constant red signal. The reflector 1, pushbutton switch 2, and display 3 are installed so as to face the road (see FIGS. 2 and 3).

As shown in FIG. 1, the reflector plate 1 is provided directly below the ultrasonic transmitter/receiver 6 of the ultrasonic sensor 5, and its tilt angle relative to the side of the road can be freely adjusted. By changing the inclination angle of the reflection plate 1, the traveling direction of the ultrasonic waves emitted from the ultrasonic transceiver 6 can be changed.

The push-button switch 2 is provided at a position where it can be pushed down especially when the driver of the two-wheeled vehicle rides the vehicle, and when the push-button switch 2 is pushed down, the drive signal is sent to the OR circuit 1 of the ultrasonic sensor 5, which will be described later.
It is set to output to 4.

The display device 3 lights up when a display drive signal from a traffic signal control circuit C that controls the traffic light at the intersection is input via the drive circuit 4, and the display device 3 lights up when the display drive signal from the traffic signal control circuit C that controls the traffic light at the intersection is inputted via the drive circuit 4. A message is displayed indicating that the computer will wait until .

In the ultrasonic sensor 5, when an electric signal for emitting ultrasonic waves is applied from a transmission amplifier 7 to an ultrasonic transceiver 6 equipped with a piezoelectric transducer using a piezoelectric bimorph, the piezoelectric transducer generates ultrasonic vibrations. Then, the ultrasonic transceiver 6 emits ultrasonic waves. When the ultrasonic transmitter/receiver 6 receives the reflected wave reflected by the object to be sensed, such as a two-wheeled vehicle or a four-wheeled vehicle, the piezoelectric transducer vibrates to generate an electrical signal, and this electrical signal is received. Amplify with amplifier 8. Thereafter, the amplified detection signal of the sensed object is transmitted to the timer circuit 12 and further outputted to the traffic signal control circuit C via the OR circuit 14. Reference numeral 9 is a timing generation circuit that generates the ultrasonic transmission frequency and its cycle width, etc., which controls the ultrasonic transceiver 6 and the transmission amplifier 7 to emit ultrasonic waves at an appropriate timing, and after a certain period of time has elapsed, an appropriate timing generation circuit. The receiving amplifier 8 is controlled so as to receive the reflected waves at the appropriate timing. A volume 10 is connected to the timing generation circuit 9. This volume 10 is used to regulate the time during which the receiving amplifier 8 can receive reflected waves after the ultrasonic wave is emitted, and by increasing the resistance value, the receivable time is increased and the reflected waves from a distance are It is now possible to receive waves as well.
Further, a volume 11 for adjusting the amplification degree is also connected to the receiving amplifier 8. Note that this receiving amplifier 8 can detect a sensing object while the vehicle is running by detecting the Doppler effect of reflected waves.

The timer circuit 12 determines whether or not the detection signal from the receiving amplifier 8 is a reflected wave from a sensed object.
If the signal is input continuously for a period longer than the time set in , it is determined that the wave is a reflected wave from an object to be sensed, and this determination signal is output to the OR circuit 14 .

The OR circuit 14 is configured so that when a drive signal from the push button switch 2 or a determination signal from the timer circuit 12 is input, a relay is operated and a sensing signal is output to the traffic signal control circuit C.

Operation Next, the operation of the semi-sensitive traffic signal control vehicle sensing device of the present invention will be explained.

First, the ultrasonic sensor 5 emits ultrasonic waves of a desired frequency from the ultrasonic transmitter/receiver 6 into the air via the reflector plate 1 . After a certain period of time has elapsed since the ultrasonic wave was emitted, when the ultrasonic transmitter/receiver 6 receives a reflected wave reflected by a vehicle such as a two-wheeled vehicle or a four-wheeled vehicle stopped in front of an intersection, the ultrasonic transceiver 6 receives a reflected wave based on this reflected wave. The detection signal is sent to the timer circuit 12 via the receiving amplifier 8.
sent to. When a vehicle is continuously present in the detection area, this received signal is continuously outputted from the receiving amplifier 8 for more than the time set by the volume control 13, so the timer circuit 12 detects the detected object This determination signal is output to the OR circuit 14. The OR circuit 14 inputting the judgment signal in this way outputs a sensing signal to the traffic signal control circuit C, and then the display drive signal from the traffic signal control circuit C is used to drive the display 3.
lights up. Therefore, a vehicle stopped in front of an intersection will always be automatically detected by the ultrasonic sensor 5 if the vehicle has been stopped at that spot for at least the preset time of the timer circuit 12. The indicator 3 will also indicate whether or not your vehicle has been detected.
This can be confirmed by visual inspection.

Furthermore, if the vehicle stops at different positions, such as in a two-wheeled vehicle, the ultrasonic sensor 5 may not detect the vehicle. In such a case, the driver only has to press down on the push button switch 2. That is, when the driver presses down the push button switch 2, the drive signal is activated.
It is input to OR circuit 14, and from this, OR circuit 1
4 outputs a sensing signal to the traffic signal control circuit C, and then the display 3 lights up in response to the display drive signal from the traffic signal control circuit C, and from this it is possible to know that the own vehicle has been detected. .

The semi-sensitive traffic signal control vehicle sensing device of the embodiment detects vehicles as described above, but the reflection plate 1 provided directly below the ultrasonic transmitter/receiver 6 of the ultrasonic sensor 5 is Since the ultrasonic wave is emitted through the ultrasonic transducer, the device itself can be made smaller, and water droplets such as rain do not attach directly to the ultrasonic transducer, making it advantageous to install it on the side of the road. It is. In addition, since the ultrasonic waves are emitted from the road side, the detection area is wider than that of conventional overhead methods, and even when detecting vehicles using the Doppler effect, speed displacement can be accurately detected. There are advantages such as being able to Furthermore, since the reflector plate 1 is tiltable, it is possible to accurately detect a vehicle even if the height of the device itself is increased to prevent tampering.

Effects of the Invention As described above, the present invention includes an ultrasonic sensor that emits ultrasonic waves and obtains reflected waves from a sensed object within a certain period of time, and a push button switch for a two-wheeled vehicle. Since the sonic sensor detects a sensed object or outputs an OR output when the push button switch is pressed down, the driver of the two-wheeled vehicle depresses the push button switch or the ultrasonic sensor If the reflected waves from the vehicle can be obtained, the presence of a vehicle can be reliably detected under any of these conditions, and unlike optical sensing devices, there is no need to protect the sensor from direct sunlight, so it is installed. It has practical effects such as not having the above restrictions and not requiring maintenance, inspection, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a vehicle sensing device for semi-sensitive traffic signal control according to the present invention, and FIG.
This figure is an external view of the semi-sensitive traffic signal control vehicle sensing device, and FIG. 3 is a diagram showing an installation example of the semi-sensitive traffic signal control vehicle sensing device. 1...Reflector, 2...Push button switch, 5
...Ultrasonic sensor.

Claims (1)

[Claims for Utility Model Registration] [1] An ultrasonic sensor 5 that emits ultrasonic waves and obtains reflected waves from a sensed object within a certain period of time;
A push button switch 2 for a two-wheeled vehicle, and an OR output is output when the ultrasonic sensor 5 detects a sensed object or when the push button switch 2 is pressed down. Vehicle sensing device for semi-sensitive traffic signal control. [2] Vehicle sensing for semi-sensitive traffic signal control according to claim 1 of the utility model registration, characterized in that it is equipped with a reflector plate 1 that can reflect ultrasonic waves and change the direction of travel of the ultrasonic waves. Device. [3] OR when the detection output of the ultrasonic sensor 5 continues for a preset time or more or when the push button switch 2 is pressed down
A vehicle sensing device for semi-sensitive traffic signal control according to any one of claims 1 to 2, which outputs an output. [4] The semicircular device according to any one of claims 1 to 3 of the utility model registration claim, wherein the means for detecting an object to be sensed by the ultrasonic sensor 5 utilizes the Doppler effect of reflected waves. Vehicle sensing device for sensitive traffic signal control.