JPS5936764B2 - Mobile object position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a system in which the position of an existing section in a section divided along the travel path of a mobile object traveling on a fixed travel path is shared between a ground fixed device (referred to as a ground station) and a mobile object. It is characterized by the fact that the device detects in a non-contact connection state using guide wires, and the ground station can simultaneously detect when a moving object enters or exits a section.

Conventionally, when using the inductive coupling method, a signal current of a specific frequency is applied to a crossed parallel two-wire induction wire that is stretched along the running route and intersects according to the determined section of the running track. A loop coil (antenna) coupled to the guide line and an amplitude level detector are mounted on the moving body to detect changes in the amplitude level at the crossing position of the guide line during movement, and count the number of times this is detected. There is a method in which the moving object self-detects its position on the road, or conversely, a signal generator with a specific frequency is placed on the moving object and a signal current is passed through the loop coil. When moving while being combined with the above-mentioned crossed two-wire induction line, a vibration level detector installed at one end of the above-mentioned induction line detects changes in the amplitude level of the induced voltage or current at the crossing position. A method is used in which the position of a moving object is detected on the ground side by counting the number of times. However, since all of these methods detect a large amplitude change in voltage or current at a position where the guide wires intersect, they have the disadvantage that erroneous detection of an amplitude change due to noise interference will cause a counting error. As is clear from the above, one side sends out a signal wave and the other side receives it and detects the position, so if both need position detection, different signal waves may be used. Dual equipment was required. In the present invention, when the ground station and mobile station equipment are inductively coupled, a feedback oscillation loop circuit is configured, and the oscillation frequency changes each time a mobile object passes an intersection of guide lines at a dividing point of a divided section of a running road. It is characterized by knowing the section position of a mobile object by using the above-mentioned conventional noise interference and coupling loss fluctuations due to movement, and is highly reliable, and the ground station and mobile station simultaneously detect the position. Therefore, it has a wide range of applications, such as being able to provide inexpensive and highly reliable equipment for automatic operation of trains, vehicles, cranes, etc.

The present invention will be explained in detail below using the drawings. FIG. 1 is a diagram showing the principle of construction of an inductive wire and a coupling loop coil used in the present invention.

In the figure, 1, 1', and 2 are parallel three-wire induction wires, 3 and 4 are transformers (for coupling), 5 is a terminal resistance of the induction wire, 6 and 7 are loop coils for coupling, and CS is an inductive coupling section. It is. As shown in Figure 1a, the guide lines 1, 1', 2 are, for example, 30 (1-J
Spread out on the same plane at regular intervals of MoV1. The coupling transformer (T1) 3 is connected between one end of the induction wire 2 and the midpoint of the primary coil of the transformer (T2) 4, and the coupling transformer (T2) 4 is connected between one end of the induction wires 1 and 17. and a terminating resistor 5 is connected to the other end of each lead wire. The coupling loop coil 6 shown in FIG. 1b is an example of a crossed type, and in this case, the coil 6 is coupled with the induction wire shown by the broken line to generate an induced voltage by the current in the direction of the solid arrow in FIG. 1a. (In other words, it couples with the inductive wire), but is canceled out by the current in the direction of the dashed arrow, and the induced voltage is zero, that is, there is no coupling with the inductive wire. Further, the coupling loop coil 7 has a characteristic that, contrary to the loop coil 6, it is coupled to the current in the direction of the broken line arrow, but is not coupled to the current in the direction of the solid line arrow.
Therefore, as can be easily understood from FIG. 1, the input 5 of the coupling transformer 3 generates the output 5 in the coupling loop 6 to transmit a signal by inductive coupling, and the input 5 of the coupling transformer 4 5
generates an output 5 to the coupling loop 7 and transmits the signal. Also, the phases of the currents due to both inputs 5 and 5 to transformers 3 and 4 are as shown by the solid line arrow and the broken line arrow in figure a, respectively.
Since the coupled loop coils 6 and 7 have the same size and shape, one of which is intersecting and the other is non-intersecting, there is no coupling, and 5-(i)C
The packing loss between 5 and 57 varies depending on the length of the section length CS of the guide wire, the signal frequency, etc., but approximately 60 dB can be obtained. In this description, loop coils are used as the coupling coils 6 and 7, but these may also be magnetic core coils, and the coils 6 and 7 may be placed one on top of the other.
In addition, in order to further strengthen the coupling suppression between 5-5a5 and V, a balancing variable resistor is connected between the connecting portions of the coupling transformers 3 and 4 and the terminals, or between the terminating resistor 5, or between each lead wire. Known balancing means, such as connecting a balancing capacitor to the In this way, a signal transmission path for each of the coupling coils 6 and 7 can be constructed by using the CS section of the guide wire as a parallel three-wire guide line. Second
The figure is a configuration example diagram of the device of the present invention, and 1, 1', 2 in the figure
, 3, 4, 5, 6, 7 are the same as in Fig. 1, 8 is an amplifier,
9 and 12 are frequency discriminators, 10 and 13 are square wave converters including low-pass filters, and 9 and 10, and 12 and 13 constitute section position signal generation circuits, respectively.

11 is an oscillation amplifier circuit, and its constituent elements are 111-1
, 111-2 are high-Q resonator circuits whose resonance frequencies are Fl and f2, respectively, 112-1 and 112-2 are phase shifters, and 113 is an amplifier (hereinafter 113 is the first, 8 is the second (referred to as an amplifier).

In addition, the extension sections CS of the guide line along the running route are A, B, and C.
, D, and the guide lines 1 and 17 intersect at each division point of the sections. Now, one end of the two parallel wires made up of the induction wires 1 and 11 is terminated with the terminating resistor 5 (two), and the other end is connected to the primary coil of the coupling transformer 4. Since the secondary side of transformer 4 is connected to the input side of oscillation amplifier circuit 11, if there is an input signal from transformer 4, it is applied to two resonators 111-1 and 111-2, respectively.
The frequency component of f1 or F2 is extracted, and after passing through phase shifters 112-1 and 112-2, respectively, it is amplified by first amplifier 113 and output to coupling transformer 3.

Further, the transformer 3 supplies its input with a signal current as indicated by the solid arrow shown in FIG. The difference Δf between f1 and F2 is from 50 to 500 Hz, and the phase shifter will be explained later. In Fig. 2, the combination of parallel three-wire induction wires 1, 1', 2 and 1,170) parallel two-wire induction wires, in other words, when the input of transformer 3 is output to transformer 4, or vice versa. According to actual measurements, the loss when Fl, f2 is 30kHz~
In the 300kHz0LF band, this coupling loss is over 60dB. If it is expressed as 113-3- in Figure 2
Since a feedback loop circuit of MO-4-111112-113 is formed, the difference between the gain μ of the first amplifier 113 and the feedback factor β between the 3rd and 112nd inputs of this loop circuit is 1 and the feedback phase ψ\O. It is possible to set it so that the following holds true, and therefore oscillation does not occur when there is no coupling with the loop coils 6 and 7 of the moving body. During this non-oscillation period, the output of the oscillation amplifier circuit 11 is input to the frequency discriminator 12, but a normal discrimination output is not generated and no output is generated from the next square wave converter 13. On the other hand, on the moving body side, when loop coils 6 and 7 are not connected to the induction wire, loop coil 6 is connected to the input of amplifier (AMP) 8, loop coil 7 is connected to the output of AMP 8, and 8-J is connected to the input of amplifier (AMP) 8. A U-8 feedback loop oscillation circuit is formed, but since the loop coil 6 is a crossed type and the loop coil 7 is a non-crossed type, even if these two coils are overlapped, the coupling loss is about 6.
0 dB, it is possible to set the gain of AMP8 to μ and the feedback rate of the loop path to β2 so that μ7β(1 holds true, and in this case, no oscillation occurs.

Next, when the moving object is in the CO guide line section of the running road, the loop coil 6 is coupled to the parallel three-wire guide wire, and the loop coil 7 is coupled to the parallel two-wire guide wires 1 and 1'.

Now, if the coupling loss between the loop coil 6 and the parallel 3-wire induction wire is M1, and the coupling loss between the loop coil 7 and the parallel 2-wire induction wire is M2, then when the induction wire and the loop coil are properly coupled. The feedback loop circuit is 8-J wire l2-guide wire 1
, 1/-4-11-3 - Guide wire 1, 1', 2-M1-6
-8 is formed.

Here, the gain of the first amplifier 113 of the oscillation amplifier circuit 11 is μ
, the gain of the second amplifier 8 is μ7, and the feedback factor β2 is the sum of the coupling losses M1, M2 and other losses. However, the combined loss of transformers 3 and 4, resonator 111 and phase shifter 112, which is the other loss mentioned above, is significantly smaller than M1 and M2, so β2+M1×M2
It can be seen that the following equation, which is one of the oscillation conditions for this feedback loop circuit, can be satisfied. μ〆β2〉1 ・・・
(1) As an example, μ and μ7 are both 40 dB. Both M1 and M2 -30dB
In this case, μ〆β2=40+4
0-60=20 dB, and one of the oscillation conditions is satisfied.

Furthermore, in the above feedback loop circuit, the induction wire and the loop coil 6,
The condition that there is no coupling with 7 and there should be no oscillation, that is, 1.
Parallel 3-line guiding line due to 17.2 and parallel 2 due to 1.11
Condition μβ that oscillation does not occur only due to the coupling between wires
1 and the condition that the second amplifier 8 does not oscillate only due to the coupling between the loop coils 6 and 7, β<1, is μ=μ/−40d.
When B(1), it is easy to make β and μ7 at least 50 dB or less, μ β = 40-50 = -10 dB × 1,
It is satisfied that 〆β′<1.

Next, the phase of the feedback voltage of the feedback loop circuit, which is another oscillation condition when the coupling between the induction wire and the loop coil is normal, will be explained.

Each of the circuit elements of the feedback loop circuit 8-1M2...-M1-18 has its own phase shift amount, so this feedback loop circuit has a phase shifter (PS) 112 for each Fl and f2. is provided, and the phase shift of the loop circuit is adjusted in advance so that ψ=0 when oscillating and ψ=π (1800) when oscillation is stopped. To be more specific, when the loop coils 6 and 7 are coupled via the induction wire in the A section and the C section within the CS section, for example, the f1 wave oscillates at the route of the high Q resonator 111-1. In order to achieve this, if the first amplifier 113 is assumed to be a two-stage amplifier, the phase shifter 112-1 is adjusted so that the input phase of the first amplifier 113 is in phase with the output phase, and it is stabilized as positive feedback (ψ=00). to oscillate. Furthermore, when the loop coils 6 and 7 are coupled via the induction wire in sections B and D, the two parallel wires 1 and 1' are crossed, so the input phase of the primary coil of the transformer 4 is Inversion (i.e. 1801
Shift), and the input phase of the first amplifier 113 becomes the opposite phase (ψ=1800) to that in the A and C sections, resulting in negative feedback, so the oscillation by the f1 wave stops. On the other hand, in this case, in order to oscillate the F2 wave determined by the high-Q resonator 111-2, if the phase shifter 112-2 is adjusted so that the input and output phases of the first amplifier 113 are in phase, the above-mentioned feedback F2 wave oscillation by the loop circuit is performed stably. By adjusting the phase shifters 112-1 and 112-2 in this way, when the loop coils 6 and 7 move to each section A-D, each time they pass the intersection of the 1, 1' parallel two-wire guide wire, The oscillation frequency of the oscillation circuit using the feedback loop circuit is switched from f1 to F2, and from F2 to f1. As mentioned above, in the example of FIG. 2, when the loop coil 7 is coupled to the A or C section, it can oscillate the F wave, and when it is coupled to the B or D section, it can oscillate the F2 wave. , if A
It is inconvenient if the gain μ of MPll3 is large and the phase adjustment by PSll2-1 or PSll2-2 happens to cause the feedback phase ψ of the 113-3-MO-4-111-112-113 loop circuit to be 00. that's why,
A phase shifter is attached to AMP8, and ψ\0 of the above 113→113 loop circuit for f1 and F2 waves, for example, ψ=
±π/2, and in the above 8-M2-M1-8 loop circuit, it is sufficient to satisfy the expression ψ=0.

Furthermore, it is easy to connect each loop coil to the guide wire so that M and M2 have a smaller coupling loss than β and y. For example, both Ml and M2 can have a coupling loss of about 40 dB or less, and β and β7 can have a feedback rate of about 60 dB0), but in this case, it is necessary to set μ and μ7 to 40 dB or more and 60 dB or less. Now, in the CS of the running path, each time the mobile object moves through each section of A, B, C, and D, the F wave and the F2 wave are alternately oscillated. A.M.
If the output of P8 is discriminated between the f1 wave and the F2 wave by discriminators DISCl2 and DISC9, binary state detection can be obtained.

That is, for example, when the output of DISCl2 is input to the next-stage square wave converter STl3, it first passes through a low-pass filter to remove noise, and then is converted into a square wave and converted into a binary signal (1,
0 or H, L level) output DPl is generated. Similarly, on the mobile side, DP2 is output from STlO. D
Since Pl and DP2 are outputs that are 1, 0 or inverted in level each time the loop coil 7 passes an intersection of the guide wires, these should be led to a counting circuit (not shown) or the like to be converted and output into an address code. It is clear that both the ground station and the mobile can detect the position of the mobile. Note that if the coupling loss between the loop coil and the induction wire of the moving body varies greatly during running, an amplitude limiter may be added to the input side of the frequency discriminators 9 and 12. It is also useful for improving the S/N ratio by limiting the amplitude of external impulsive noise.

Also, in particular, a BPF that passes f1 and F2 to the amplifier 8.
is attached, and the S/N ratio of the feedback amplifier circuit against external noise is improved as necessary. Furthermore, in the example shown in FIG. 2 above, the oscillation amplifier circuit 11 is provided on the ground station side and the amplifier 8 is provided on the mobile body side, but in contrast, the circuit 11 is provided on the mobile body and the amplifier 8 is provided on the ground station side. It is clear that the same operation can be obtained even if each is provided separately. Now, in order to apply the device as shown in Fig. 2 to an actual moving route, it is necessary to divide the running route into long sections (CS sections in Fig. 2), and then to divide the running route into long sections (CS sections in Fig. 2), and then divide the system into long sections where position detection is required. Divide the area into an arbitrary number of short sections (A, B, C, ...), and install the above parallel three-wire guide wire for each long section, and parallel to the short sections. The two outer lines of the three lines are crossed, and the ground station equipment as shown in Figure 2 is installed at one end of the long guide line.

However, if there are a plurality of moving bodies on which the on-vehicle device of FIG. 2 of the present invention is mounted within each long section (CS) above, F,
Since the oscillation of the wave or F2 wave is unstable and the position of the moving object cannot be detected, there is only one moving object within one long section. In practice, when multiple moving objects are run on a road, the distance between the moving objects is determined by the travel control performance of the moving objects, and the minimum distance for each long section is regulated by this, and It is necessary to perform travel control such that only one moving object can exist. Therefore, if a moving object enters these long sections, oscillation by the fl wave or F2 wave will occur in each divided section, and if the moving object moves out of the long section, the oscillations of Fl and f2 will stop. The presence or absence of a moving object within the CS section can be detected from the ground station equipment for the long section CS, and as explained above, the position of the moving object for each small section such as A-D is detected as the moving object advances. . In the device of the present invention, as described above, an amplitude limiter is installed before the frequency discriminator for the fl wave and F2 wave, and the moving object passes through the intersection position of the parallel two-wire guide wire by 1 and 1' for the output of the frequency discriminator. A low-pass filter with a cutoff frequency corresponding to the maximum speed is provided for each (all are not shown), and a second
The amplifier 8 includes a bandpass filter (
(not shown), it is possible to suppress impulsive noise that enters the feedback loop oscillation circuit and to improve the S/N ratio, thereby suppressing the generation of erroneous position detection outputs. Detection of entry and exit of a moving object for each long section and continuous position detection for each short section within the existing length section are performed as shown in Fig. The equipment cost is low because it uses the same general equipment and the same equipment as each ground station, and since it does not use tracks etc., even vehicles with rubber tires can run on a fixed route. Significant practical effects can be obtained, such as detecting the section position with high reliability.

Although a more detailed explanation will be omitted, for example, it is easy to share the device shown in Figure 2 and configure an information signal transmission device between a ground station and a mobile object with a small number of additional circuits. It has a wide range of uses, such as detecting section positions and stopping positions of moving objects, in automatic travel control of vehicles, vehicle operation management at ground stations, etc.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle of construction of the induction wire and loop coil used in the present invention, and FIG. 2 is a diagram showing the principle of the apparatus of the present invention. 1, 1', 2...Parallel 3-wire guide wire, 3, 4...
...Transformer, 5...Terminal resistor, 6, T.
...Loop coil, 8,113...Amplifier (AMP), 9,12...Frequency discriminator (D
ISC), 10, 13...Square wave converter, 11
...Oscillation amplifier circuit, 111 ... High Q resonator, 112 ... Phase shifter.

Claims (1)

[Claims] 1. As a device that detects the position of a mobile object moving along a certain travel route, which has been divided into sections in advance, by both the ground fixed equipment and the mobile object, Then, extend three parallel lines at equal intervals in the same plane, intersect the outer two lines at the division points of the subsections that are further divided into the above section, and set the terminal at one end of the three parallel lines. Connect a resistor, connect the primary coil of the first transformer between the outer two wires of the three parallel wires to the opposite end, and connect the center wire end of the three parallel wires and the primary coil of the first transformer. A cross-shaped parallel three-wire guide wire formed by connecting a primary coil of a second transformer to an intermediate point, and inductively coupled with the cross-type parallel three-wire guide wire within the section that is placed on a moving body; A mobile antenna consisting of a pair of non-crossing loop coils and a pair of crossing loop coils that are hardly directly coupled to each other, and an oscillation amplification consisting of two sets of resonators each having a different frequency, a phase shifter, and a common first amplifier. a second amplifier that commonly amplifies the two different frequencies; a frequency discriminator that is connected to the respective outputs of the oscillation amplifier circuit and the second amplifier and that discriminates between the two frequencies; The movable body side includes a square wave converter for shaping, and each section position signal generation circuit on the ground fixed equipment side, and the oscillation amplification circuit is connected to each secondary coil of the first transformer and the second transformer. In between, the second amplifier is connected between the pair of mobile antennas, or the oscillation amplifier circuit is connected between the pair of mobile antennas, and the second amplifier is connected between the first transformer and the second transformer. is connected between each secondary coil of the moving body, and only when the moving body is in the divided section, the first and second transformers, the crossed parallel three-wire induction wire, and the crossed loop coil of the moving body are connected. A feedback oscillation circuit is formed between the crossed loop coil, the oscillation amplifier circuit, and the second amplifier, so that when the moving object moves from one small section of the position detection section to the next small section, no crossing occurs. Since the phase of the induced voltage due to the coupling between the loop coil and the outer two wires of the crossed parallel three-wire induction wire is reversed, the voltage determined by the two resonators is applied to the feedback oscillation circuit each time the small section passes through the loop coil. The position of the moving object is determined by the occurrence of oscillation and the number of changes in the oscillation frequency up to the current position of the moving object. A mobile object position detection device characterized in that it is capable of detecting both ground fixed equipment and the mobile object.