JPH0575207B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an object detection device for detecting vehicles constituting a train, for example, and in particular, the present invention relates to an object detection device for detecting vehicles constituting a train. The present invention relates to an object detection device that detects its own failure in a configuration where signals are concentrated in a signal transmission device. [Technical Background of the Invention] In general, a traffic management system that detects the train number of a running train on the ground side, uses this detection result to know the position of the train, and manages the train operation status, etc. has already been developed. This has been realized on railways such as the Shinkansen and on-site railways at steel works. The configuration of this device for detecting objects such as train numbers is
It is configured as described in Publication No. 26328. That is, different resonance frequencies f1, f2, f3, f4,
A resonator with f5 is made to correspond to a vehicle code, and the resonator is connected to, for example, a loop antenna to form a response device, and this response device is installed in a vehicle, which is the object to be detected, and resonates at the marker resonance frequency fM. A marker response device consisting of a marker resonator, a loop coil and a capacitor will be installed on the ground side. On the ground side, an interrogation device is configured that radiates into space an interrogation signal whose frequency changes continuously, including frequencies f1 to f5 and a resonance frequency fM, through a loop antenna installed on the ground. The answering device is placed at an appropriate position so that the interrogation signal radiates into the space through which the answering device passes. In this case, the marker response device and the interrogation device are arranged so that they are always electromagnetically coupled. According to the above configuration, the marker response device resonates at the marker frequency fM due to the interrogation signal from the interrogation device and generates a response signal even while the response device installed in the vehicle is not approaching. In addition, a vehicle equipped with a response device approaches the ground loop antenna,
When electromagnetic coupling occurs between the loop antenna of the transponder and the transponder, the interrogation signal causes the transponder to
Resonates at the resonant frequency of the selected resonator. As a result, a response signal is generated in the response device. These response signals are also induced in the ground loop antenna. A failure of the interrogation device is detected by extracting this induced response signal from the interrogation device, determining at which frequency it resonates, and verifying whether a marker frequency component is included every time the interrogation signal is swept. The number code of the vehicle equipped with the response device can be detected by signal verification of frequencies f1 to f5 among the frequency components included in the response signal. Hereinafter, the above-mentioned conventional object detection device will be explained in detail with reference to FIGS. 2 and 3. The interrogation device 20 shown in FIG. 2 includes a frequency oscillator 22 that emits a signal whose frequency changes continuously including frequencies f1 to f5 and fM as shown in FIG. The loop antenna 21 radiates signals into the air. The response device 10 has a loop coil 14, which is connected via a capacitor 13 to a resonator 11 that resonates at a frequency f2 and a resonator 1 that resonates at a frequency f4.
2 are connected in parallel. Also, the frequency fM
Marker resonator 33 and loop coil 3 that resonate with
4 and a capacitor 32, the marker response device 30 is installed near the ground loop antenna 21 of the interrogation device 20. The transponder 10 is attached to a vehicle to be detected, and when this vehicle approaches and the transponder 10 is electromagnetically coupled to the interrogation device 20, the frequency f1 ~ radiated from the ground loop antenna 21 of the interrogation device 20 is
With f5 and fM and a continuously changing interrogation signal,
It resonates at predetermined resonance frequencies f2 and f4 and generates a response signal. Furthermore, the marker response device 30 resonates at the marker frequency fM due to the interrogation signal radiated from the ground loop antenna 21, and generates a response signal. These response signals are sent to the ground loop antenna 21.
The interrogation device 20 easily detects the response signal shown in FIG. 3b from this response signal. Frequencies f1 , f2, f3, f4,
The synchronous pulse generator 40 outputs the synchronous series pulse shown in FIG. 3c in which the response timings of f5 and fM are ON. The synchronization pulse from the synchronization pulse generator 40 is matched with the response signal, an AND condition is obtained, and the shift register 50 shifts the synchronization pulse while synchronizing with the synchronization pulse.
The data shown in the figure can be retrieved. After sweeping all frequencies, the marker detection device 60 always verifies that the marker bit corresponding to the frequency component of the marker response device 30 is "1". This test is conducted using the response device 1 installed on the vehicle.
0 is not electromagnetically coupled to the interrogation device 20 , and it is possible to determine whether the ground loop antenna 21, the transmitter 22, the shift register 50, and the marker response device 30 are normal. In the conventional object detection device as described above, a large number of interrogation devices 20 are installed along the track, and each of them detects the response device 10 installed in a passing vehicle.
It becomes possible to detect the movement of vehicles across the entire line, and it is possible to provide vehicle detection data to vehicle operation management systems, etc. To do this, it is necessary to connect a signal transmission device or the like to interrogation devices installed along each track and send the detected vehicle code to the center. In this case, failures in the signal transmission device and the central receiving device that receives the vehicle code are often detected at the timing when the data is transmitted, and at that timing, the vehicle code may be lost and the vehicle cannot move across the entire line. There is a danger that a situation could arise that would have a major impact on the management of [Object of the invention] The present invention was made based on the above circumstances, and
It is an object of the present invention to provide an object detection device that can immediately detect a failure in transmission including a signal transmission device and a reception device in addition to failure detection in an interrogation device. [Summary of the Invention] In order to achieve the above object, an object detection device according to the present invention is installed on an object to be detected, and is configured to generate resonance for a predetermined frequency component of an interrogation signal consisting of a plurality of frequency components. an interrogation device that radiates the interrogation signal into space toward the interrogation device and receives a predetermined frequency component of the interrogation signal that the response device resonates from the interrogation device; a marker response device that is always electromagnetically coupled to the device and responds to a specific frequency component of the interrogation signal and always returns a resonant frequency component, and the interrogation device is connected to the response device and the marker response device; A transmission device that encodes and transmits the received frequency component; and a transmission device that receives the code transmitted by the transmission device and detects failures of the interrogation device and the transmission device depending on the presence or absence of a code corresponding to the frequency component of the marker response device. The present invention is characterized by comprising a means for detecting. [Embodiment of the Invention] An embodiment of the object detection device according to the present invention will be described below with reference to FIG. 1, in which the same parts as in FIG. 2 are given the same reference numerals. That is, in FIG. 1, there is an interrogation device 20, and a response device 10 installed in a vehicle (not shown) as a detection target.
The marker response device 30, which is always electromagnetically coupled to the interrogation device 20, is arranged in the same manner as in FIG. As a result, when the response device 10 attached to a vehicle or the like approaches the interrogation device 20 and is electromagnetically coupled to the interrogation device 20, the response device 10 resonates as shown in FIG. 3b. frequency f2 and
The bit corresponding to the frequency component of f4 and the frequency component of fM at which the marker response device 30 resonates is “1”.
becomes. On the other hand, when the response device 10 is not electromagnetically coupled to the interrogation device 20, the bit corresponding to the frequency fM component at which the marker response device 30 resonates becomes “1” as shown in FIG. 3a. . The contents of the shift register 50 including this marker bit are transferred to the transmission device 100, and the transmission device 100
is transmitted to the receiving device 110 using a predetermined transmission method, and the receiving device 110 transmits the detection signal of the interrogation device 20 including the marker bit inputted by the transmission device 100 from the shift register 50 to the central failure detection device 12.
Output to 0. Here, if the transmission is performed normally, bit data identical to the contents of the shift register 50 is input to the central failure detection device 120. According to the above, the central failure detection device 120:
The detection signal including the input marker bit is first tested for the presence or absence of the marker bit, and the marker bit is "1".
The interrogation device 20, the transmission device 100, the reception device 110, and the marker response device 3
It can be determined that there is a failure in any of the 0 devices. Therefore, by not using data without marker bits, false detection can be prevented.
Further, by verifying the presence or absence of a marker bit input from the interrogation device 20 at each transmission timing, it is possible to immediately detect a failure in the interrogation device 20, the transmission device 100, the reception device 110, and the marker response device 30. As described above, according to this embodiment, the vehicle code from this object detection device, which is used as vehicle detection data for a vehicle operation management system, etc., is sent to the central side by connecting a signal transmission device etc. to the interrogation device. In this case, transmission failures can be detected immediately, making it possible to minimize losses in vehicle operation management. Since the failure detection function in this embodiment is performed regardless of the transmission method of the transmission device, the configuration of the transmission device may be modified in various ways. [Effects of the Invention] As described above, according to the present invention, in a configuration in which the device parts for detecting a vehicle are distributed and the detection signals are concentrated by the signal transmission device, the signal transmission device and the reception device are included. Therefore, it is possible to provide an object detection device that can immediately detect transmission failures.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the object detection device according to the present invention, Fig. 2 is a block diagram showing an example of a conventional object detection device, and Fig. 3 explains the operation of Fig. 2. FIG. DESCRIPTION OF SYMBOLS 10... Response device, 20... Interrogation device, 30... Marker response device, 40... Synchronization pulse generator, 50
...Shift register, 100...Signal transmission device, 11
0...Signal receiving device, 120...Failure detection device.

Claims (1)

[Claims] 1 A detection target is equipped with two sets of response devices that resonate with a predetermined frequency component of an interrogation signal consisting of a plurality of frequency components, and a device that directs the interrogation signal toward the response device in space. an interrogation device that emits and receives from the response device a predetermined frequency component of the interrogation signal with which the response signal resonates; a marker response device that always returns a resonant frequency component in response to the response device; a transmission device that encodes and transmits the frequency component that the interrogation device receives from the response device and the marker response device; An object detection device characterized by comprising means for receiving the code and detecting a failure of the interrogation device and the transmission device based on the presence or absence of a code corresponding to a frequency component of the marker response device.