JPH0218260B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention is applicable to, for example, automatic train control (abbreviated as ATC).
Alternatively, electromagnetic coupling may be caused between an on-board antenna installed on a vehicle moving on a certain route equipped with speed control information transmission means such as automatic train operation (abbreviated as ATO) and a loop coil installed on the ground. The present invention relates to a vehicle position detection method for transmitting ground position information to a vehicle.

A typical point detection method in which a traveling vehicle detects its own passing point has conventionally been carried out by a method called a variable frequency method, which has a circuit configuration schematically shown in FIG. In other words, a in the same figure is a block diagram showing the main part of the variable frequency on-board device, in which a signal of frequency f ₀ oscillated by the oscillator OSC, which uses the on-board antenna CA as a feedback circuit, is passed through its band filter BPF ₀ . It is constantly outputting. However, when the on-board antenna CA passes over _the ground element G consisting of a resonant circuit with a frequency _f1 , which is shown as a block in _FIG . The position of the ground element G is detected on the vehicle by causing the frequency to change and the output from the filter BPF ₀ to be lost.

However, the above detection method requires equipment for a resonant element with a high Q called a ground element, which is separate from the speed control information transmission means installed on the ground. As a result, the reception level of position information received on the vehicle fluctuates, resulting in drawbacks such as reception loss at times.

The present invention uses a portion of a transmission line for transmitting speed control information to provide a loop coil formed to generate lines of magnetic force that are in phase different from the lines of magnetic force of the original speed control signal at required points on the vehicle travel path. However, the phase difference between these lines of magnetic force is detected by the phase difference of the signals received on the vehicle by electromagnetic induction, and the point is detected.It is intended to contribute to the simplification of ground equipment. It is.

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3.

FIG. 2 shows an example in which a position information source is set using a transmission line laid in a loop for transmitting speed control information for each block section set on a vehicle travel route. Loop 1 is installed as a speed control information transmission path along one block section along the vehicle travel path, and speed control information v is transmitted from transmitter 2 to loop 1.
Loop 3 is a loop that uses a part of loop 1 and has its lead-in lines parallel to each other as shown in the figure, and is appropriately formed and arranged at a predetermined point to serve as a source of point information p in place of the conventional ground wire G. It is a coil.

In addition, the symbol indicated by A in the same figure indicates the direction of the magnetic field lines generated on the inner surface of Loop 1 when the information current flowing through Loop 1 is in the direction of the arrow, and the symbol indicated by B indicates the direction of the magnetic field lines generated on the inner surface of Loop 1 when the information current flowing through Loop 1 is in the direction of the arrow. Therefore, the direction of the magnetic field lines generated on the inner surface of the loop 3 is
There is a phase difference of 180° between magnetic field lines A and B. A failure detection circuit 5 is connected to the output circuit of the transmitter 2 via a transformer 4, and detects failure of transmission of the speed control information v due to disconnection of the loop 1 or the like. The above is the entire outline of the ground equipment according to the present invention.

Next, antenna 6 is an on-vehicle antenna for receiving speed control information v flowing through loop 1, and is tightly coupled to loop 1 and loosely coupled to loop 3.
Antenna 7 is an on-vehicle antenna that is installed to receive information v from loop 1 when it is not on loop 3, and to receive a signal with a phase different from information v from loop 1 when it reaches loop 3. . In addition, the block circuits within the dashed-dotted line frame shown in the same figure show the configuration of the on-board equipment. Matching section 1 connected to upper antenna 7
0, the filter section 11, and the phase comparator 12 constitute a position information receiving circuit, and the phase comparator 12 detects the phase of the signal received via the antenna 7 and the phase of the speed control information v received via the antenna 6. and outputs position information p.

As shown in FIG. 3a, loops 3 and 3', which are point information generation sources, are arranged at each predetermined point using a part of loop 1, which is a speed control information transmission path, and the loops are 1 on the vehicle antenna 6
and antenna 6 when 7 moves in the direction of the arrow
and 7, in which b in the figure shows the voltage level V of the antenna 6, and c in the same figure shows the changes in the voltage level V' of the antenna 7. Note that (+) and (-) in the figure represent phase polarity. As shown in Figure b, the antenna 6
The voltage level V' of the antenna 7 hardly changes when passing over the loops 3 and 3', but as shown in Figure c, the voltage level V' of the antenna 7 changes when passing over the loops 3 and 3'. At this time, it receives a signal with a phase that is 180° different from the speed control information it had previously received. This change in phase is detected by a phase comparator 12 onboard equipment, and position information p is output.

As is clear from the above embodiments, the present invention has the feature of enabling point detection without requiring a ground element having a high Q resonance element, and detecting a failure of loop 3, which is a position information transmitting element. This is possible by monitoring the information current v sent to loop 1, which is the speed control information transmission path, and furthermore, since point detection is performed using part of loop 1, ground equipment can be simplified. It has remarkable effects such as

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an outline of a device for implementing the conventional variable frequency vehicle position detection method, FIG. 2 is a circuit configuration diagram showing an example of equipment for implementing the vehicle position detection method of the present invention, and FIG. The figure is an explanatory diagram of the voltage level received by the on-board antenna; figure a is a positional relationship diagram between the ground loop and the on-board antenna; figure b is a time chart of the voltage level received by the on-board antenna 6; c is a time chart of the voltage level received by the antenna 7. 1: Vehicle speed control information transmission loop, 2: Transmitter, 3: Point information generation source loop, 7: On-vehicle antenna for point information reception, 12: Phase comparator.

Claims (1)

[Claims] 1. A transmission line for transmitting vehicle speed control information from the ground to the vehicle is laid in a loop over one block section of the vehicle travel route, and the vehicle speed control information transmission loop is installed at a required point on the vehicle travel route. A part of the control information transmission loop is introduced to form and arrange a point information generation source loop that generates magnetic lines of force having a phase opposite to the lines of magnetic force generated inside the vehicle speed control information transmission loop due to the current of the control information. and an on-vehicle antenna for receiving control information, which is closely coupled to the vehicle speed control information transmission loop and loosely coupled to the point information source loop, and tightly coupled to the point information source loop. an on-vehicle antenna for receiving point information, and means for comparing the phase of a control information signal from the on-board antenna for receiving control information with a signal from the on-board antenna for receiving point information; A method for detecting the position of a vehicle, characterized in that when the vehicle passes through the point information source, the phase comparison means detects passage through the point information source loop.