JPH09160647A - Carriage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carriage fitted with a collision preventing device which eliminates the need for both carriages to stop at a confluence point or intersection by securing a safe distance between the carriages only by one device. SOLUTION: Of the carriage fitted with the collision preventing device, the collision preventing device is equipped with a transmitting coil 1, a receiving coil 2, a transmitting and receiving circuit 3 having a receiving circuit 5 which processes the signal from the receiving coil and outputs a driving stop signal and a transmitting circuit 4 which sends a sent signal to the transmitting coil, and a timing circuit 7 which outputs a timing signal to the receiving circuit and transmitting circuit. The receiving circuit 5 has a self-diagnosing function which detects its transmission output and removes an output-reduced transmission output from the detection signal, compares the remaining detection signal with a reference signal, and outputs a device abnormality signal when the detection signal is relatively low. The timing circuit 7 has a means which modulates transmission cycles and reception cycles at random.

Description

Detailed Description of the Invention

This application is the 1995 patent application No. 1 which the applicant has already applied.
This is an application that is technically related to No. 30565 (filed on May 29, 1995).

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier vehicle having a collision prevention device and traveling along a predetermined traveling route or route.

[0002]

2. Description of the Related Art Due to the current trend of labor saving, carrier vehicles
It is spreading rapidly. Even in a factory that introduced several units in the beginning,
After that, in order to further rationalize, there is a tendency to add the number of guided vehicles. The transport vehicle has a travel route or route provided on the travel surface (the "travel route or route" varies depending on the type of the steering mechanism of the transport vehicle. It is formed by a metal band or the like). As long as the number of vehicles used is small, sufficient travel routes can be secured for each vehicle.

[0003] Conventionally, what must be considered in a carrier is a collision with another carrier due to a speed difference between the carriers. As a conventional collision prevention device attached to a carrier vehicle, an ultrasonic sensor utilizing reflection of ultrasonic waves and a sensor utilizing electromagnetic induction are known.

FIG. 33 is a block diagram of an ultrasonic sensor mounted on a conventional carrier vehicle. The ultrasonic sensor comprises a combination of an ultrasonic wave transmitter 21, an ultrasonic wave detector 22 and an electronic circuit 23. The fan shape connected to the ultrasonic transmitter 21 indicates the transmission range 24, the fan shape connected to the ultrasonic detector 22 indicates the reception range 25, and the overlapping area 28 of both fan shapes is the detectable range (operating range) of the detection object. Is.

In the ultrasonic sensor, when another carrier vehicle (object to be detected) enters the operating range, the ultrasonic wave emitted from the ultrasonic transmitter 21 is reflected by the other carrier vehicle and the like. It enters the detector 22, is processed by the electronic circuit 23, and outputs a stop signal 6 to a drive mechanism (not shown). The stop signal 6 can stop the carrier and prevent collision.

Such an ultrasonic sensor collision prevention device for a carrier vehicle has been necessary and sufficient for the purpose of preventing a rear-end collision with a preceding vehicle.

As another conventional technique, a collision prevention device utilizing electromagnetic induction is known. Collision prevention device using electromagnetic induction, compared to collision prevention device using ultrasonic sensor,
It has a feature that the reception range can be relatively widened. FIG. 36 is a block diagram of a conventional collision prevention device using electromagnetic induction. The collision prevention device includes a transmission-only coil 1, a reception-only coil 2, and a transmission / reception circuit 3 that processes a transmission / reception signal.

The transmission / reception circuit 3 has a transmission circuit 4 for driving the transmission-dedicated coil 1 and a reception circuit 5 for processing a signal detected by the reception-dedicated coil 2 and outputting a stop signal 6. . The reception circuit 5 has an amplification detection circuit 5a, a prohibition circuit 5b, and an output circuit 5c. The prohibition circuit 5b is provided for the purpose of preventing a malfunction due to a transmission signal emitted from the transmission-dedicated coil 1 by itself, and a reception-dedicated coil during transmission. It functions so that the signal received in 2 is invalidated and the stop signal 6 is not output.

In the operation of the conventional collision prevention device using electromagnetic induction, the transmission circuit 4 transmits intermittently via the transmission-dedicated coil 1 in order to inform another carrier of its existence. The receiving circuit 5 constantly searches for transmissions from itself and other vehicles via the receiving-only coil 2. When the transmission from another carrier is received, it is detected by the amplification detection circuit 5a, the prohibition circuit 5b confirms that it is not its own transmission signal, and the output circuit 5c outputs the stop signal 6 to stop the drive of the carrier. . A signal corresponding to the transmission period is sent from the transmission circuit 4 to the prohibition circuit 5b, and reception is disabled during the transmission period of the transmission circuit 4.

FIG. 37 shows an example of mounting a collision prevention device using electromagnetic induction on a carrier vehicle. FIG. 37 (1) is a plan view of the transport vehicle equipped with the collision prevention device.
(2) is a front view of the carrier. 4 in FIG. 37 (1)
The rectangular shape shown by the two broken lines is the drive wheel, and is shown in FIG. 37 (2).
The arrow indicates the direction of travel. The reception-only coil 2 is attached to the front side in the traveling direction of the transport vehicle, and the transmission-only coil 1 is attached to the rear side
Is installed, and the transmission / reception circuit 3 is installed in the transport vehicle.

[0011]

A problem with such a conventional guided vehicle is a matter relating to a traveling route for guiding the guided vehicle. As long as the number of vehicles used was small, we were able to secure sufficient travel routes for each vehicle.
However, since high productivity is desired in the same space due to the limitation of capital investment, a large number of transport vehicles have been introduced, and the space given to the travel route of each transport vehicle has become smaller.

[0012] Therefore, a situation such as merging, branching or crossing between a plurality of transport vehicles, which has not been conventionally considered, will occur. At the time of the newly generated merge, intersection, or the like, there is a possibility that a collision between the transport vehicles may occur.

The disadvantages of the conventional ultrasonic sensor collision prevention device are as follows. First, there is a disadvantage that the detection distance cannot be extended. It is the figure which looked at the traveling of the conveyance vehicle which attached the ultrasonic sensor collision prevention device to Drawing 34 from the upper part. As shown in the figure, two left and right ultrasonic sensors are attached to the front side in the traveling direction of the transport vehicle. Here, if the transmission output or the detection sensitivity is increased in order to extend the detection distance of the ultrasonic sensor, other obstacles such as the wall of the building are inevitably detected, and the two transport vehicles stop moving without stopping. . As described above, if the detection sensitivity is increased, the detection is frequently stopped and the efficiency of automation of conveyance is not improved.

Second, the conventional carrier has a drawback that it is difficult to prevent a collision at a merge or an intersection. FIG. 35 shows a case where the transport vehicles A and B merge (the transport vehicle A travels from A ′ to A in the arrow direction, and the transport vehicle B also travels in the arrow direction). The transport vehicles A and B shown in FIG. 35 have two more points than the transport vehicles shown in FIG. 34 in order to prevent a collision at the time of merging.
An ultrasonic sensor is added at a position at an angle of ± 90 ° with respect to the traveling direction. Although the detection range in the left-right direction can be expanded by this added ultrasonic sensor, depending on the merging timing, the other carrier vehicle is detected at the same time,
As shown in the right part of 5, both transport vehicles may stop.

38 and 39, the trouble of another conventional collision preventing device (FIG. 36) using electromagnetic induction will be described. FIG. 38 is a receiving characteristic diagram when the receiving coil 2 is installed in the horizontal direction with respect to the traveling surface of the carrier vehicle.
The receiving coil 2 located in the center of the figure is a range in which the transmitting coil of another carrier having a certain constant output can be detected. As is clear from this directional characteristic, a dead point with almost no sensitivity occurs in the axial direction of the receiving coil 2 (angles 90 degrees and 270 degrees shown in the figure).

As shown in FIG. 39, at the dead point where the positional relationship between the reception-only coil 2 of the carrier vehicle A and the transmission-only coil 1 of another carrier vehicle at the center of the figure is a positional relationship of an angle of about 270 degrees. , The sensitivity is almost lost, and the carrier A
Cannot recognize the positions of other transport vehicles. Similarly, even if the angle is about 90 degrees, the other party cannot be recognized. As described above, the conventional collision preventing device has a problem that the collision cannot be prevented when there is a partner vehicle that enters from the dead point.

As described above, the conventional technologies (the ultrasonic sensor-based collision prevention device and the electromagnetic induction-based collision prevention device) have the following problems. It is difficult for a conventional collision prevention device using an ultrasonic sensor to secure a wide directivity and a sufficiently safe detection distance required at the time of merging or intersecting. Since the ultrasonic sensor is structurally limited in directivity, a large number of sensors are required to detect a wide range. If a plurality of sensors are used, they may interfere with each other and thus malfunctions are likely to occur.

Further, if an attempt is made to extend the detection distance, since reflection is used, a wall or the like in the factory is detected and an unnecessary stop occurs. Furthermore, depending on the angle at the time of merging, there is a case where both carriers are stopped and do not move while detecting each other.

A conventional collision prevention device using electromagnetic induction has a dead point in reception characteristics. This dead point makes it difficult to reliably prevent collisions at intersections.

Therefore, it is desirable that the directivity of the collision preventing device for a carrier vehicle has a reception characteristic that can secure a safe distance in consideration of the braking distance of the carrier vehicle without causing an unnecessary stop. Furthermore, if collisions can be prevented at the time of merging / intersecting, the freedom of travel routes can be expanded and the limited space in the factory can be effectively used. In order to solve these problems, it is possible to easily realize collision prevention at the time of merging / intersecting by using only one device (standalone type) for each transport vehicle without providing a higher-level transport vehicle group controller. Realization of a collision prevention device is desired.

Therefore, the present invention provides a collision prevention device which can secure a safe distance between the transport vehicles and can merge and intersect without the both transport vehicles being stopped by using only one device for each transport vehicle. It is intended to provide an attached carrier.

It is a further object of the present invention to provide a carrier equipped with a collision prevention device capable of easily obtaining the required directivity with only one device.

It is another object of the present invention to provide a vehicle equipped with a collision prevention device having a transmission characteristic different from the conventional transmission characteristic.

It is another object of the present invention to provide a carrier vehicle having a self-diagnosis function capable of easily identifying a carrier vehicle in which a transmission abnormality has occurred.

[0025]

A vehicle according to the present invention is a vehicle equipped with a collision prevention device, the collision prevention device including a transmission coil, a reception coil, and a signal from the reception coil. A transmission / reception circuit having a transmission circuit for transmitting a drive signal to the transmission coil and a transmission circuit for transmitting a transmission signal to the transmission coil, and a timing circuit for outputting a timing signal to the reception circuit and the transmission circuit. The receiving circuit detects its own transmission output, removes the reduced transmission output from the detection signal, and outputs a device abnormality signal when the remaining detection signal is relatively low compared with the reference signal. It has a self-diagnosis function, and the timing circuit
It has means for randomly modulating the transmit period and the receive period. The carrier according to the invention thus acts such that the timing circuit randomly modulates the transmission and reception periods. For this reason, even if a plurality of transport vehicles travel and the transmission synchronization happens accidentally, the transmission will be lost at the next moment, and the signal of the previously transmitted transport vehicle will be transmitted to other transport vehicles. You will receive it. Furthermore, the present invention has a self-diagnosis function, and outputs an apparatus abnormality signal when the transmission output of itself becomes abnormally low during the period other than the output reduction period. As a result, it is possible to prevent an accident in which the vehicle is not detected and collides with another carrier due to a reduction in the transmission output.

The carrier according to the present invention is the above-mentioned carrier, wherein the receiving circuit further includes a coil end-to-end voltage detection circuit, a second prohibiting circuit, a third prohibiting circuit, and a comparing circuit. The voltage detection circuit detects the voltage of the receiving coil, and the second prohibition circuit invalidates the voltage across the coil corresponding to the transmission from another vehicle based on the modulation signal from the timing circuit, The prohibiting circuit of No. 3 invalidates the voltage across the coil corresponding to the transmission output of which its output is reduced, and the comparison circuit causes the output of the third prohibiting circuit to correspond to the normal transmission output of its own. In comparison with a predetermined reference voltage that is relatively lower than the output of the inhibition circuit, the device abnormality signal is output when the output falls below the reference voltage. The carrier according to the present invention is thus
The self-diagnosis function is realized by using two prohibition circuits and a comparison circuit.

In the carrier vehicle according to the present invention, further, in the above carrier vehicle, the comparison circuit outputs the device abnormality signal for the first time when the output of the third prohibiting circuit falls below the reference voltage a plurality of times. The carrier according to the present invention is thus
When the output from the third prohibition circuit in the comparison circuit falls below the reference voltage a plurality of times, the device abnormality signal is output only when the own transmission signal interferes with the transmission signals from other vehicles and the reception signal is received. It is possible to prevent the device abnormal signal from being output by detecting a sudden output reduction phenomenon.

The carrier according to the present invention is a carrier equipped with a collision prevention device, wherein the collision prevention device comprises:
A transmission loop circuit having a transmission loop antenna, a reception coil, a reception circuit that processes a signal from the reception coil and outputs a drive stop signal, and a transmission circuit that transmits a transmission signal to the loop antenna, the reception circuit, and A timing circuit for outputting a timing signal to the transmission circuit, wherein the timing circuit has a random number generator and a modulation circuit,
Randomly modulate the transmit and receive periods. The carrier according to the invention thus uses a loop antenna instead of the transmitter coil. According to the loop antenna disclosed in the present invention, since the transmission characteristics are spread in all directions of the carrier vehicle, there is no dead point, and the possibility of collision occurrence is reduced.

A carrier vehicle according to the present invention is the above-mentioned carrier vehicle, wherein the transmission circuit further includes a transmission output reduction circuit that reduces the transmission output in response to the output of the reception circuit. Reduce output. Since the carrier vehicle according to the present invention thus reduces the output while the carrier vehicle is stopped, it does not interfere with other carrier vehicles.

The carrier vehicle according to the present invention is the above-mentioned carrier vehicle, wherein the prohibiting circuit disables the receiving function of the receiving circuit during its own transmission period in response to the modulated signal from the timing circuit. . In this way, the transport vehicle according to the present invention is provided with the inhibition circuit in the reception circuit and disables the reception function during the transmission period of itself, thereby avoiding the malfunction of receiving and stopping the transmission of itself.

The carrier according to the present invention is the above-described carrier, wherein the receiving circuit further detects its own transmission output, removes the output-reduced transmission output from this detection signal, and leaves the remaining detection signal. When it is relatively lower than the reference signal, a self-diagnosis function of outputting a device abnormality signal is added. In this way, the carrier vehicle according to the present invention outputs the device abnormality signal when the transmission output of itself is abnormally low during the output reduction period by the self-diagnosis function. As a result, it is possible to prevent an accident in which the vehicle is not detected and collides with another carrier due to a reduction in the transmission output.

The carrier according to the present invention is the above-mentioned carrier, wherein the receiving circuit further includes a coil end-to-end voltage detection circuit, a second prohibiting circuit, a third prohibiting circuit and a comparing circuit. The voltage detection circuit detects the voltage of the receiving coil, and the second prohibition circuit invalidates the voltage across the coil corresponding to the transmission from another vehicle based on the modulation signal from the timing circuit, The prohibiting circuit of No. 3 invalidates the voltage across the coil corresponding to the transmission output of which the output is reduced, and the comparing circuit makes the output of the third inhibiting circuit relative to the output corresponding to its normal transmitting output. When the output of the third inhibiting circuit falls below the reference voltage a plurality of times as compared with a predetermined reference voltage which is lower than the reference voltage, a device abnormality signal is output. The carrier according to the present invention is thus
The self-diagnosis function is realized by using two prohibition circuits and a comparison circuit.

A transport vehicle according to the present invention is a transport vehicle equipped with a collision prevention device, wherein the collision prevention device processes a loop antenna for transmission, a receiving coil, and a signal from the receiving coil. A transmission / reception circuit having a reception circuit that outputs a drive stop signal and a transmission circuit that transmits a transmission signal to the loop antenna, and a timing signal is output to the reception circuit and the transmission circuit to randomly generate a transmission cycle and a reception cycle. And a transmission coil connected to the transmission circuit, a part of the loop antenna is wound around the transmission coil, and both ends of the loop antenna are connected to switch means. The switching means operates so as to be closed by the switching signal from the output reduction circuit while the transmission output is being reduced and open during the normal period of the transmission output. , And change the transmission range of the loop antenna in a substantially circular shape. As described above, the carrier vehicle according to the present invention outputs the device abnormality signal only when the output from the third prohibiting circuit falls below the reference voltage a plurality of times in the comparison circuit, thereby transmitting its own transmission signal and other carrier signals. It prevents a device abnormal signal from being output by detecting a sudden output reduction phenomenon of a received signal due to interference with a transmitted signal from a vehicle.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments 1, 2, and 3 of a carrier vehicle according to the present invention will be described below with reference to the accompanying drawings. The first embodiment is a case where the receiving (dedicated) coil is fixedly arranged on the front side of the carrier vehicle, and the receiving (dedicated) coil is fixedly arranged on the rear side thereof, and the second embodiment is arranged with two coils arranged before and after the carrier vehicle. Is selectively switched to be used as a transmission coil and a reception coil, and the third embodiment is a case where a loop antenna is used for transmission. The same members are designated by the same reference numerals, and duplicate description will be omitted.

[Embodiment 1] Embodiment 1 is a vehicle equipped with a collision prevention device using electromagnetic induction. A receiving coil is provided on the front side in the traveling direction of the vehicle and a transmitting coil is provided on the rear side in the traveling direction. It is characterized by being attached.

(Overall Structure) FIG. 1 shows an overall structure of a collision prevention device used in a carrier vehicle according to the first embodiment. The collision prevention device shown in FIG. 1 according to the first embodiment is different from the conventional collision prevention device shown in FIG. 36 in that a timing circuit 7 is provided and an output reduction circuit 4a is provided in the transmission circuit 4. . This collision prevention device is composed of a transmission (dedicated) coil 1, a reception (dedicated) coil 2, and a transmission / reception circuit 3 provided between these coils.

The transmission / reception circuit 3 is connected to the transmission coil 1 to drive the coil 1, and is connected to the reception coil 2 to process a signal detected by the coil 2 and output a stop signal 6. And a timing circuit 7 for sending timing signals to the transmission circuit 4 and the reception circuit 5.

The reception circuit 5 includes an amplification detection circuit 5a to which the transmission signals of its own carrier vehicle and other carrier vehicles detected by the receiver coil 2 are input, and a prohibition circuit 5b provided in the subsequent stage.
And an output circuit 5c which receives an output signal from the prohibiting circuit 5b and outputs a stop signal 6 to a drive mechanism (not shown) of the transport vehicle.

The transmission circuit 4 has an output reduction circuit 4a, and the output signal (stop signal 6) of the output circuit 5c is also input to this output reduction circuit 4a. By this signal input, the transmission output from the transmission circuit 4 to the transmission coil 1 is relatively reduced compared to the normal output when the vehicle is stopped.

The timing circuit 7 includes a random number generator 7b,
The random number generator 7b has a modulation circuit 7a that modulates the fundamental period of the transmission signal and the reception signal according to the random number, and creates a random modulation signal as described later in detail. The modulation circuit 7a outputs the modulated signal to the transmission circuit 4 and the inhibition circuit 5b in the reception circuit 5, respectively.

The transmitting circuit 4, which has received the modulated signal, intermittently transmits at the modulated cycle. The prohibiting circuit 5b is provided for the purpose of preventing a malfunction such as detecting a transmission signal emitted by the transmitting coil 1 of its own and stopping driving.
During the transmission, the signal received by the receiving coil 2 is invalidated, and the stop signal 6 is not output. That is, the signal obtained from the receiving coil 2 is prevented by the modulated signal from the timing circuit 7 during the transmission period from the transmitting coil 1.
It is invalidated by b. Instead of the modulation signal from the timing circuit 7, the prohibiting circuit 5b has a conventional technique (FIG. 36).
You may use the output of the transmission circuit 4 similarly to.

(Transmitting / Receiving Timing) FIG. 2 is a timing chart for specifically explaining the modulation action of the timing circuit 7 of the first embodiment with respect to the basic period of transmitting / receiving. As described above, the timing circuit 7 has the modulation circuit 7a and the random number generator 7b, and the random number generator 7b.
, Randomly modulates the basic cycle of transmission and reception generated by the timing circuit 7 within a specific range.

In FIG. 2, (1) and (2) are the transmission output and the reception output of the basic cycle T (for example, 150 msec) of the timing circuit 7, which are transmitted during the high (H) period of (1). Is possible, and reception is possible during the high (H) period of (2) (the conventional device of FIG. 36 uses only this). (3) is a random number ΔTn generated by the random number generator 7b within a range (± T / 4) of the basic period T.
(4) and (5) are the transmission output and the reception output of the modulated output in which the random number (3) of the random number generator is superimposed on the transmission (1) and the reception (2) of each basic period T, respectively. .

Here, the random number ΔT from the random number generator 7b is read at the beginning of the basic cycle T of every transmission and reception, and the transmission and reception output is modulated into the cycle T + ΔTn and output from the timing circuit 7. For example, as shown in the figure, since the random number generator 7b generates ΔT1 (= 0) at the beginning of the first cycle T, the cycle of the transmission / reception output after modulation is T + ΔT1 =
Since the random number generator 7b generates ΔT2 in the second cycle T, the transmission / reception output after modulation has a cycle T + ΔT.
2, and in the third cycle T, the random number generator 7b immediately outputs Δ
Since T3 is generated, the transmission / reception output after modulation has a period T
It becomes + ΔT3. This modulation has a range of random number ΔT of ± T /
Since it is within the range of 4 and is overlapped with each basic period T, each period T +
ΔTn is set and they do not accumulate mutually. In this way, the fundamental cycle of transmission and reception is modulated.

(Transmission Output Reduction Timing) FIG. 3 shows the case where the collision prevention device (FIG. 1) shown in the first embodiment is attached.
It is a figure explaining the timing of the operation of the output reduction circuit 4a at the time of joining with another conveyance vehicle. This will be described with reference to FIG. In the figure, (1) is a signal received by the receiving coil 2 from the transmitting coil 1 of another carrier. (2) is an output from the amplification detection circuit 5a in the reception circuit 5 which detects the transmission signal of the other carrier of (1). (3) is the output from the output circuit 5c, that is, the stop signal 6. (4) is the output of the transmission circuit 4, that is, the output of the transmission coil 1.

Transmission signal from another carrier (Fig. 3 (1))
When receiving the signal, the amplification detection circuit 5a generates an output (see FIG.
(2)) When the prohibiting circuit 5a determines that the transmission signal is not its own (determined by the signal from the timing circuit 7), the stop signal 6 is output from the output circuit 5c, and the transmission signal from another transport vehicle is output. It occurs continuously until it disappears (Fig. 3
(3)). During the period when the stop signal 6 is generated (that is, when the guided vehicle is stopped), the stop signal 6 is also supplied to the output reduction circuit 4a, and the transmission output from the transmission coil 1 is reduced to a lower output than usual (Fig. 3 (4)).

(Operation of Embodiment 1) The operation of the collision prevention device used in the carrier vehicle of Embodiment 1 of FIG. 1 is as follows.
A signal from the transmission coil of another carrier is detected by the reception coil 2, detected by the amplification detection circuit 5a in the reception circuit 5, and disabled by the prohibition circuit 5b during transmission from its own transmission coil 1 and is being transmitted. If not (that is, if it is confirmed that the signal is a transmission signal from another carrier), the stop signal 6 is output from the output circuit 5c and the carrier stops driving. The stop signal 6 is also supplied to the output reduction circuit 4a of the transmission circuit 4 at the same time, and while the transport vehicle is stopped, the reception coil of the other priority transport vehicle showing the existence of itself to the following transport vehicle and merging / intersecting. The transmission output from the transmission coil 1 is reduced so that the transmission signal does not reach.

During transmission, the reception function is invalidated by the prohibiting circuit 5b, but even if the transmission is synchronized with other transport vehicles, it is assumed that a plurality of transport vehicles with the reception function not operating simultaneously occur. However, in each transport vehicle, the transmission circuit 1 and the reception coil 2 have different transmission and reception cycles that change momentarily due to the modulation effect of the timing circuit 7, and the reception invalid (transmission) period does not continue. Absent.

(Example of installation of anti-collision device and directional characteristics)
FIG. 4 shows an example of mounting the collision prevention device described in the first embodiment. Here, the transmitter coil 1 and the receiver coil 2 are mounted vertically to the floor.

At this time, the directivity has a circular directivity (non-directivity) around the transmission coil 1 and the reception coil 2 as shown in FIG. 5 as a normal transmission range and reception range. The output from the transmission coil 1 is reduced as compared with the normal transmission range when a signal of another transport vehicle (detection object) is detected as described above, and the transmission range at the time of detecting another vehicle indicated by a small circle is shown. become.

(Specific operation at the time of merging) Next, referring to FIG. 6 and FIG.
A specific operation and transmission / reception timing when the two transport vehicles A and B merge will be described with reference to FIG. As shown in FIG. 6, when the receiving coil 2 detects a signal emitted from the transmitting coil 1 of the transport vehicle A when the transport vehicle B travels from the position B ′ to the position B (that is, the transport vehicle as seen in the figure). When the transmitting coil 1 of the carrier A enters the receiving range of B or when the receiving coil 2 of the carrier B enters the transmitting range of carrier A), carrier B
Stops. At the same time, the carrier B reduces the transmission output from the transmission coil 1 (indicated by a broken small circle). Since the receiving coil 2 of the transport vehicle A does not enter the narrowed transmission range of the transport vehicle B, the transport vehicle A can join without being interfered with by another transport vehicle B. Since the reduced transmission output of the carrier B also reaches the front receiving coil of another carrier following the same traveling route, there is no risk of a rear-end collision.

In FIG. 6, assume that the transmissions of both vehicles A and B happen to be synchronized. During transmission, reception is invalid due to the action of the prohibiting circuit 5b on both the transport vehicles A and B, so that they cannot recognize each other. However, carrier vehicles A and B
As described with reference to FIG. 2, since the random transmission / reception cycle is modulated independently, each transmission / reception cycle T + ΔTn changes independently every moment and the synchronization state, that is, the reception invalid state continues. Without doing so, at the next moment, whichever is transmitted first will be prioritized and merged.

FIG. 7 shows the transmission / reception timing at the time of merging. In the figure, (1) is the transmission output of the transport vehicle A, high (H) is the output during normal transmission, and low (L) is the reduced output when another transport vehicle is detected (when the transport vehicle is stopped).

(2) is the transmission signal of the carrier A, and the thick black line is the transmission signal output period. The broken line indicates the basic period T described with reference to FIG. 2, and the transmission signal output period is randomly modulated with respect to the basic period T.

(3) is a received signal of the carrier vehicle A. The thick black line indicates the reception invalid period (due to the action of the prohibiting circuit 5b), and this period temporally corresponds to the transmission signal output period of (2). Therefore, the space between adjacent thick black lines indicates the receivable period.

(4) is the transmission output of another carrier B.
Similar to (1), high (H) represents a normal output during transmission, and low (L) represents a reduced output during detection of another guided vehicle.

(5) is a transmission signal of the carrier vehicle B.
Similar to (2), the thick black line is the transmission signal output period.
By the action of the modulation circuit 7a, the fundamental period T is randomly modulated.

(6) is a received signal of the carrier B,
Similar to (3), the thick black line indicates the reception invalid period, and this period temporally corresponds to the transmission signal output period of (5). Therefore, the space between the thick black lines indicates the receivable period. The broken lines in (5) and (6) indicate the basic period T. However, since the transport vehicle A and the transport vehicle B transmit on the basis of independent timing circuits, respectively, (2) and (3) ) There is a time difference with respect to the basic cycle (broken line).

Explaining with reference to FIG. 6 at the same time, the carrier B transmits the transmission signal from the carrier A (FIG. 7B).
Is detected during the receivable period in FIG. 7 (6) and stopped, and at the same time, the transmission output of the carrier B in FIG. 7 (4) is reduced from high (H) to low (L). Therefore, the carrier A is the other carrier B
It is possible to join without being interfered by the reduced output of.

It is assumed that both transport vehicles A and B accidentally transmitted at the same time (synchronization). However, since the transport vehicles A and B are subjected to the random modulation as described with reference to FIG. 2, the synchronization does not continue as shown in FIGS. The one sent first will be given priority and will be joined. In the example of FIG. 7, as can be seen from (2) and (6), the carrier A transmits first after the synchronization occurs.

As described above, in the related art, the problem that both ends at the time of merging shown in FIG.
It does not occur because the other party is detected at a sufficiently safe distance in consideration of the braking distance with respect to the merge, and the transmission output is reduced at the same time when the other party is detected.

The carrier vehicle having the collision prevention device according to the first embodiment described above can solve the problems of the prior art described in the section of the problem to be solved by the invention, and conveys even at complicated merging / intersection points. It is possible to prevent a collision between cars. Even if a higher-level group controller that controls multiple vehicles is not installed and controlled, simply install the collision prevention device on each vehicle (so-called stand-alone type) and the application range of the vehicle (travel) The degree of freedom of the route) can be expanded.

(Collision preventive device with self-diagnosis function) FIG. 8 shows a modification of the first embodiment shown in FIG. 1, which constantly monitors its own transmission output and outputs a device abnormality signal when the transmission output is abnormally reduced. It is a figure which shows the whole structure of the collision prevention apparatus with a self-diagnosis function which warns by doing. Compared to the configuration of FIG. 1, the collision prevention device with a self-diagnosis function of FIG. 8 (1) includes the inhibition circuit 5b (FIG. 1) in the reception circuit 5 as a first inhibition circuit 5b.
As shown in FIG. 8, a coil end voltage detection circuit 5d, a second prohibition circuit 5e, a third prohibition circuit 5f, and a comparison circuit 5g are newly provided.

The collision prevention device with a self-diagnosis function shown in FIG. 8A is composed of a transmission (dedicated) coil 1, a reception (dedicated) coil 2 and a transmission / reception circuit 3 provided between these coils.

The transmission / reception circuit 3 has a transmission circuit 4, a reception circuit 5, and a timing circuit 7 for sending timing signals to the transmission circuit 4 and the reception circuit 5.

The receiving circuit 5 includes an amplification detection circuit 5a and a first detection circuit 5a.
Prohibiting circuit 5b and output circuit 5c for outputting stop signal 6
And have The first prohibition circuit 5b corresponds to the prohibition circuit 5b in the configuration of FIG. Further, the receiving circuit 5 is connected to both ends of the receiving coil 2 and constantly detects the voltage between both ends of the coil.
The second prohibition circuit 5e for invalidating the output of the both-end voltage detection circuit 5d and the second prohibition circuit 5 are supplied with the modulation signal from the output of d and the timing circuit 7 during the period other than the transmission period.
The third prohibiting circuit 5f for invalidating the output signal from the second prohibiting circuit 5e while the stop signal 6 outputted from the output circuit 5c and the stop signal 6 outputted from the output circuit 5c are supplied. And a comparison circuit 5g which compares the output signal from the third prohibiting circuit 5f with the reference voltage Vth and outputs the device abnormality signal 18 when the output signal is lower than the reference voltage Vth.

The transmission circuit 4 has an output reduction circuit 4a, and the stop signal 6 is also input to the output reduction circuit 4a. Due to this signal input, the transmission output from the transmission circuit 4 to the transmission coil 1 is relatively reduced from the normal output while the vehicle is stopped.

The timing circuit 7 includes a random number generator 7b,
It has a modulation circuit 7a and randomly modulates the fundamental period.
The modulation circuit 7a outputs the modulated signal to the transmission circuit 4 and the inhibition circuit 5b in the reception circuit 5, respectively.

The operation of the collision prevention device with the self-diagnosis function will be described. The self-diagnosis function uses the device error signal 1 when the transmission output drops abnormally during transmission with normal output.
Acts to output 8. Specifically, the coil-end voltage detection circuit 5d detects the coil-end voltage of the receiving coil 2 which receives the transmissions from the carrier itself and other vehicles.

Among them, the received voltage signals from other vehicles are not related to the self-diagnosis, so that the second prohibiting circuit 5e is provided, and the signals other than the transmission period are provided corresponding to the modulated cycle signals from the timing circuit 7. The received voltage signal during the period (receivable period) is invalidated.

Furthermore, when the carrier of the first embodiment receives a transmission of another carrier and is stopped, the transmission output is reduced to a lower output than usual. A third prohibiting circuit 5f is provided so as not to diagnose the reduced output as a device abnormality, and the output signal from the second prohibiting circuit 5e is invalidated while the stop signal is being output from the output circuit 5c. . Therefore, the third
The output signal from the prohibition circuit 5f is the transmission output of itself and the transmission output when the output is not reduced.

The output signal from the third prohibiting circuit 5f is supplied to the comparing circuit 5g. The comparison circuit 5g compares the reference voltage Vth with a value of 90% of the normal output,
When the output signal from the inhibition circuit 5f is lower than the reference voltage Vth, that is, when the device is abnormal, the device abnormal signal is output.

Here, there may occur a phenomenon in which the self-generated transmission signal interferes with the transmission signals of other vehicles, and the voltage across the receiving coil 2 temporarily drops. Due to such a phenomenon, a device abnormality signal may be output frequently, so that the comparison circuit 5f may output a plurality of times (for example, 2 times) within a predetermined time.
It is preferable that the apparatus abnormal signal 18 is first output when there is an internal output (more than once).

FIG. 9 is a timing chart of the embodiment shown in FIG. 8 (1). In the figure, (1) and (2) are the basic period T of transmission and reception, (3) is the random number ΔTn generated by the random number generator 7b, and (4) and (5) are the random numbers superimposed on the basic period. These are the transmission and reception outputs of the post-modulation period T + ΔTn. These (1) to (5) are the same as those shown in FIG.

(6) is an output voltage signal of the coil end voltage detection circuit 5d. Since the receiving coil 2 receives the transmission of itself and the transmission of another carrier, among the output voltage signals a, b, c, d, and e of the voltage detection circuit 5d across the coil,
Signals a, c, d, e corresponding to the high (H) period of (4)
Is its own transmission signal, and the signal b corresponding to the low (L) period is a transmission signal from another carrier. The transmission signal output of itself is used to generate a device abnormality signal, and the transmission signal output from another carrier is used to generate a stop signal.

(7) is an output from the first prohibiting circuit 5b. The output from the amplification detection circuit 5a is the signal a of (6).
Rises in response to all of e to e, but the first prohibiting circuit 5
By the action of b, the output during its own transmission period is invalidated,
Only the output corresponding to the signal b is output.

(8) is the stop signal 6 from the output circuit 5c
Then, the drive of the transport vehicle is stopped.

(9) is the output from the output reduction circuit 4a, and the output from the transmission circuit 4 is reduced from the normal output while the stop signal 6 is being output.

(10) is the internal output of the comparison circuit 5f, and the voltage across the coil in (6) is the reference voltage Vth (for example,
It is output when it is relatively lower than 90% of normal output). Since (a) in (6) is a normal output and b is an output from another carrier, it is invalidated by the second prohibition circuit 5e, and c is output.
Is being reduced and is being invalidated by the third inhibiting circuit 5f, and is output corresponding to d and e.

(11) is an output from the comparison circuit 5g, and when the output of (10) occurs twice within a predetermined period, a device abnormality signal is output. This signal activates a warning light, a warning buzzer, and the like.

It should be noted that it is possible to detect an abnormality in which the reduced output is further reduced when the other priority transport vehicle is stopped because it is overrun. In this case,
As in the modified example shown in (2), a second comparison circuit 5h is provided in parallel with the third inhibition circuit 5f, and the output of the second inhibition circuit is compared with a reference voltage of, for example, 90% of the reduced output. Second
The device abnormal signal of. The third prohibiting circuit 5f and the (first
The comparator circuit 5g is provided as it is, and the device abnormality signal 18 is used as the first abnormality signal. With this configuration, it is possible to detect an abnormality when the output is reduced.

[Embodiment 2] The collision prevention device of Embodiment 2 is
In principle, the two coils are attached to the floor horizontally with the detection radius shifted in the traveling direction.

(Overall Configuration of Second Embodiment) FIG. 10 is an overall configuration diagram of a collision prevention device used in a carrier vehicle according to the second embodiment. Compared with the configuration of the first embodiment (FIG. 1), the configuration of the collision prevention device shown in FIG. 10 includes a coil switching circuit 8 and, if desired, an output adjustment circuit 4B in the transmission circuit 4.
Is provided, and the signal from the timing circuit 7 is output to the coil switching circuit 8 and the output adjusting circuit 4b, respectively.

This collision avoidance device includes a coil A (1), a coil B (2), a transmission / reception circuit 3 and coils A, B (1,
2) and the coil switching circuit 8 provided between the transmission and reception circuit 3.

The coils A (1) and B (2) may be exactly the same, and both coils function as transmission coils when selectively connected to the transmission circuit 4 via the coil switching circuit 8. , Functions as a receiving coil when selectively connected to the receiving circuit 5. For the sake of convenience, in the following description, the coil A (1) is installed on the rear side of the transport vehicle, and the coil B (1) is installed.
(2) is installed on the front side of the transport vehicle.

The coil switching circuit 8 has two selectors, each of which is interlocked with a movable contact a and fixed contacts b and c. A transmission signal from the transmission circuit 4 is input to the movable contact a1 of one selector. The movable contact a2 of the other selector is connected to the amplification detection circuit 5a of the reception circuit 5 and outputs the reception signal detected by the coil. Movable contact b1
And c2 are connected to the coil B (2), and the movable contacts c1 and b2 are connected to the coil A (1). A switching signal is sent from the modulation circuit 7a of the timing circuit 7 to the coil switching circuit 8 to selectively connect the movable contacts a1 and a2 to the fixed contacts b1 and b2 or c1 and c2, respectively.

A switching signal for the coil switching circuit 8 is generated by the timing circuit 7. The switching signal is shown in FIG.
This is a signal that sequentially repeats high (H) and low (L) at the rising timing of the modulated transmission output (4). For example, the switching signal becomes high (H) at the rising of the cycle T + ΔT1, and the fixed contact a1 and the movable contact c
1, the fixed contact a2 and the movable contact c2 are respectively connected, the traveling direction rear coil A (1) is connected to the transmission circuit 4 and functions as a transmission coil, and at the same time, the front coil B (2) is connected to the reception circuit 5. And functions as a receiving coil. At the next rising of the cycle T + ΔT2, the switching signal becomes low (L), the fixed contact a1 and the movable contact b1, and the fixed contact a2 and the movable contact b2 are connected to each other, and the traveling direction rear coil A (1) is connected to the receiving circuit 5 , And at the same time, the front coil B (2) is connected to the transmission circuit 4. Hereinafter, the same is repeated.

The carrier of the second embodiment has the following features. Since the coil A and the coil B alternately function as the transmitting coil and the receiving coil, it is equivalent to providing two transmitting coils and two receiving coils with a space between the coil A and the coil B. 11 and 12 show the directional characteristics (reception characteristics) at this time. FIG.
It is a reception characteristic when the coils A and B (1, 2) are attached horizontally to the traveling surface. The two coils A and B are
They are attached so that they are displaced from each other by a distance of "detection radius". The reason for shifting the detection radius is that the effect of compensating for the dead point (FIG. 39) of the reception characteristic described above is maximized.

That is, as is clear from FIG. 11, the dead point of the coil A (1) indicated by the broken line is the coil B.
Compensation can be made with the detection radius of (2). Similarly, the dead point of the coil B (2) indicated by the broken line can be compensated by the detection radius of the coil A (1). Since the dead points are mutually compensated by the detection radius, the directivity is improved to the shape shown by the solid line. In this way, the least sensitive part of one coil can be supplemented by the most sensitive part of the other coil.

FIG. 12 shows that coils A, B (1,
The following shows the reception characteristics when (2) is mounted vertically to the running surface. Circular directivity centering on coils A and B (omnidirectional)
Is obtained. By mounting this with a detection radius shifted as shown in the figure, the directional characteristics are improved to the shape shown by the solid line. Such an embodiment may be used depending on the required specifications of the carrier.

(Transmission / Reception Timing) FIG. 13 shows the timing of the collision prevention device of the second embodiment. Compared to the timing of the first embodiment (FIG. 7), FIG. 13 is different in that the number of transmitting coils and the number of receiving coils are equivalently two. (1) to (4) are related to the carrier A,
(5) to (8) relate to the carrier vehicle B.

(1) is the transmission output 1 from the front coil B of the vehicle A, high (H) is the normal transmission output, and low (L) is the reduced output when another vehicle is detected.

(2) is the transmission output 2 from the rear coil A of the transport vehicle A. Similarly, high (H) is the output during normal transmission,
Low (L) represents a reduced output when another transport vehicle is detected (when the transport vehicle is stopped).

(3) is the transmission signal of the carrier A, and the thick black line is the transmission signal output period. The broken line indicates the basic period T described with reference to FIG. 2, and indicates that the transmission signal output period is randomly modulated with respect to the basic period T.

(4) is a received signal of the carrier vehicle A. The thick black line indicates the reception invalid period (due to the action of the prohibition circuit 5b), and this period temporally corresponds to the transmission signal output period of (3). Therefore, the space between adjacent thick black lines indicates the receivable period.

(5) is the transmission output 1 from the front coil B of the other carrier vehicle B. Similar to (1), high (H) represents a normal output during transmission, and low (L) represents a reduced output during detection of another guided vehicle. The change from high (H) to low (L) on the way is a second modified example described later, and when the front side coil B in the traveling direction receives a transmission from another carrier, The case where only the transmission output is reduced is shown.

(6) is a transmission output 2 from the rear coil A of another carrier B. Similar to (1), high (H) represents a normal output during transmission, and low (L) represents a reduced output during detection of another guided vehicle.

(7) is a transmission signal of the carrier vehicle B.
Similar to (3), the thick black line is the transmission signal output period.

(8) is a received signal of the carrier B,
Similar to (3), the thick black line indicates the reception invalid period, which corresponds in time to the transmission output period of (7). Therefore, the space between the thick black lines indicates the receivable period. The broken lines in (7) and (8) indicate the basic period T described with reference to FIG. 2 similarly to (3) and (4), but the transport vehicle A and the transport vehicle B respectively. Since transmission is performed based on an independent timing circuit, there is a time difference between both basic cycles (broken line).

Referring to FIG. 10 at the same time,
Carrier B sends a transmission from carrier A (see FIG. 13).
(3)) is detected and stopped during the receivable period in FIG. 13 (8), and at the same time, as a general rule, the transmission output 1 (FIG.
(5)), the transmission output 2 (FIG. 7 (6)) is reduced from high (H) to low (L) (in the case of the second modified example which will be described later in detail, refer to FIG. 7 (5)). Only the transmission output 1 from the front coil B is reduced as shown, and the rear coil A is reduced as shown in FIG.
The transmission output 2 from 1 is left as a normal output. ). In any case, the transport vehicle A can join without being interfered by the reduced output of the other transport vehicle B.

It is assumed that both transport vehicles A and B accidentally transmitted at the same time (synchronization). However, since the transport vehicles A and B perform random modulation by the timing circuit 7 as described with reference to FIG. 2, the overlap does not continue.

(Operation of the Second Embodiment) Next, a specific operation when the two transport vehicles A and B according to the second embodiment join together will be described. FIG. 14 shows an operation when the transport vehicles A and B face each other on two parallel traveling routes and pass each other. Here, in the case of the conventional directional characteristic, both transport vehicles stop by detecting each other. However, if the improved directivity of the second embodiment (see FIG. 11) shown by the solid line is adopted, it is possible to pass each other without interfering with each other.

FIG. 15 shows the merging mode, and FIG. 16 shows the intersecting mode. As shown in FIGS. 15 and 16, the carrier B is stopped by receiving the signal from the carrier A. here,
Since the carrier B detects the transmission of the coil 2 of the carrier A (because the transmitter coil 2 of the carrier A is included in the reception range of the carrier B), the period during which the carrier A is detected is: The transport vehicle B is stopped, and the transmission output from the coils 1 and 2 of the transport vehicle B is reduced. Therefore, the transport vehicle A can pass through without being affected by the transport vehicle B.

(Modification) FIG. 17 shows a case where the succeeding carrier vehicle B approaches the preceding carrier vehicle A on one traveling route. Example 2 has two variants that are useful in such cases. In the first modification, as shown in FIG. 10, an output adjustment circuit 4b may be added to the transmission circuit 4 in addition to the output reduction circuit 4a that outputs the coil switching circuit 8. The switching signal output from the timing circuit 7 to the coil switching circuit 8 is input to the output adjustment circuit 4b. When the switching signal is high (H) (that is, when the rear coil A (1) is functioning as a transmission coil), the output adjustment circuit 4b makes the transmission output slightly larger than the normal output, and the switching signal is low. At the time of (L) (that is, when the front coil B (2) functions as the transmission coil), the output is adjusted so that the transmission output is the normal output.

In other words, the reception range of the front coil 2 of the carrier B is expanded, and the succeeding carrier B always receives the preceding carrier A before the preceding carrier A. At this time, the transport vehicle B stops and the transmission output from the coil is reduced. Therefore, according to the principle of prioritized transport vehicle priority traveling, when the subsequent transport vehicle B approaches the preceding transport vehicle A, the subsequent transport vehicle B stops without affecting the transport vehicle A.

According to this modification, as shown in FIG. 17, even if there are two guided vehicles A and B traveling in the same direction on the same traveling route, they are received simultaneously by both guided vehicles. The problem of stopping does not occur. The difference between the transmission outputs of the front coil 2 and the rear coil 1 is determined in consideration of the distance between the coils.

A second modification of the second embodiment will be described with reference to FIG. The switching signal is input from the timing circuit 7 (via the output adjustment circuit 4b) to the output reduction circuit 4a. At this time, the output reduction circuit 4a transmits the transmission coil (coil B) on the front side of the traveling direction when receiving on the front side (coil B) of the traveling direction of the transport vehicle (that is, when the switching signal is low (L)). When the output is reduced, on the contrary, when it is received at the rear side of the traveling direction (coil A) (that is, when the switching signal is high (H)), the transmission output of the transmission coil at the rear side of the traveling direction (coil A) is reduced. You can choose not to.

According to this modified example, in the case of FIG. 17, even if the succeeding carrier vehicle B receives at the front coil 2 in the traveling direction and the preceding carrier vehicle A receives at the rear coil 1 in the traveling direction, the carrier vehicle B is Stop and reduce the output from the front coil 2,
On the other hand, the carrier A proceeds as it is and the output does not decrease.
Further, even if there is another transport vehicle following the transport vehicle B, the rear transmission coil (coil A) of the transport vehicle B has a normal output, and there is no risk of collision.

Next, FIG. 18 shows a case where the transport vehicles A and B travel on the same traveling route in opposite directions. FIG. 18 is not an operation that normally occurs, but occurs when either the transport vehicle A or B makes a wrong travel route. In this case, the carrier vehicles A and B
Each of them detects the other party and temporarily stops, and the transmission output of both transport vehicles A and B is reduced, and the transmission output is further reduced, and the two further stop. In this case, it is necessary to manually remove either the transport vehicle A or B from the travel route.

(Self-Diagnosis Function) FIG. 19 shows a collision prevention device in which a self-diagnosis function is added to the second embodiment (FIG. 10). The receiving circuit 5 of FIG. 8 is adopted instead of the receiving circuit 5 of FIG. Also in the second embodiment, a self-diagnosis function can be added if desired.

Furthermore, as described in connection with the self-diagnosis function of the first embodiment, it is also possible to adopt a configuration capable of detecting an abnormality in the reduced transmission output.

In addition, the carrier vehicle according to the second embodiment has all the features, functions, and effects described in the first embodiment.

According to the transport vehicle of the second embodiment and its modification, the collision prevention at the time of merging and crossing of the transport vehicles can be easily realized without the control of the host controller or the like. Further, since the collision prevention device incorporates ideas for realizing the following items, it is possible to safely prevent the collision between the transport vehicles even on a complicated traveling route. (1) Measures to stop both transport vehicles due to mutual interference in parallel traveling routes (2) Measures to stop both transport vehicles due to mutual interference at the time of merging and intersection (3) Leading transport vehicle and subsequent Preventing collisions due to speed differences with the guided vehicle (4) Countermeasures for stopping the preceding guided vehicle due to interference with the following guided vehicle (5) Preventing collision when facing one travel route

[Third Embodiment] A third embodiment is a vehicle equipped with a collision preventing device using a loop antenna for transmission, in which a receiving coil is provided on the front side in the traveling direction of the vehicle and a loop antenna is provided on the rear side in the traveling direction. Are attached respectively.

(Overall Configuration of Third Embodiment) FIG. 20 is a diagram showing the overall configuration of a collision prevention device used in a carrier vehicle of the third embodiment. This collision prevention device is different from the configuration of the first embodiment (FIG. 1) in that a loop antenna is provided instead of the transmission coil.

This collision prevention device is based on the loop antenna 1
a, a receiving coil 2, and a transmitting / receiving circuit 3 provided between them. The receiving coil 2 and the transmitting / receiving circuit 3 are substantially the same as those in the first embodiment. The loop antenna 1a will be described below.

As shown in FIG. 21, a width of about 60 cm × 12
This collision prevention device was attached to a prototype carrier made of aluminum having a size of 0 cm long and 32 cm high. The loop antenna 1a is wound around the entire side surface of the carrier at a height of about 15 cm from the traveling surface. The loop antenna 1a is made of a conductive material having a cross-sectional area of 0.3 mm2, and is housed inside a synthetic resin or rubber bumper (not shown) and wound around a carrier vehicle, so that the loop antenna 1a is about 3 cm from the side surface of the carrier vehicle. Are spaced.

The receiving coil 2 has a diameter of 1 cm and a length of 12 c.
A coil in which a winding wire having a diameter of 0.2 mm is wound 200 times is used for a cylindrical ferrite core of m. Receiver coil 2
The mounting position of is such that the height from the running surface to the lower end of the coil is 40
cm.

The transmission characteristics of the loop antenna 1a measured under this condition are shown in FIG. The transmission ranges measured from the loop antenna 1a in the forward, backward, and left and right directions are approximately 200 cm. The transmission range in the forward, backward, and left-right directions when the output reduction circuit 4a is operating and the output is attenuated is about 60 cm. These transmission ranges are
It is equal to the receivable range. This transmission range also changes depending on the gap between the loop antenna 1a and the vehicle body made of a metal such as aluminum or iron. The transmission range can be changed according to the required specifications by adjusting the output of the transmission circuit 4. With such a transmission range that surrounds the carrier on four sides, it is possible to prevent a collision with another carrier approaching from any direction.

(Modification) FIG. 23 is a diagram showing the overall structure of a modification of the third embodiment. It differs from the third embodiment (FIG. 20) in that a transmission coil 1, a switching device 8 and the like are added.

In this embodiment, the transmitter coil 1 is connected to the transmitter circuit 4. A part of the loop antenna 1a is wound around the transmission coil 1 so as to overlap. Specifically, the loop antenna 1a has a diameter of 1
A 5 mm synthetic resin cover is covered, and a part of the loop antenna 1a is wound around the central portion in the length direction 5 times. Therefore, the transmission coil 1 and the loop antenna 1a are magnetically coupled, but both are electrically insulated.

Both ends of the loop antenna 1a are connected to the working contact a1 of the switch 8 and one fixed contact b1. The other fixed contact c1 is not connected. That is, the switch 8 forms a switch. The switching signal of the switch 8 is supplied from the output reduction circuit 4a1 and is closed while the stop signal 6 is output and the transmission output is reduced (the operating contact a1 and the fixed contact b1 are connected and the loop antenna 1a is short-circuited). Then, the transmission output is opened during a normal period (the working contact a1 and the fixed contact c1 are connected and the loop antenna 1a is opened).

FIG. 24 shows a mounting view of the embodiment of FIG. A part of the loop antenna 1a is wound so as to overlap the transmission coil 1 on the rear side in the traveling direction. The loop antenna 1a is housed in a bumper (not shown) and wound around the entire side surface of the carrier.

FIG. 25 is a diagram showing transmission characteristics. FIG.
In the case of the above embodiment, the loop antenna 1a is simultaneously output from the transmission coil 1 in addition to the loop antenna 1a.
Since a part of the above is wound and magnetically coupled to the transmission coil 1, the transmission output from the transmission coil 1 is reduced.
After all, the transmission characteristic is that the normal transmission output has a circular transmission characteristic with a radius of about 250 cm centered on the transmission coil 1, and becomes a smaller rectangular shape when the loop antenna 1a is short-circuited when the output is reduced.

When a part of the loop antenna 1a is wound around the transmission coil 1 by 20 times or more, both ends of the loop antenna 1a are short-circuited without reducing the transmission output by using the output reduction circuit 4a. It was confirmed that a similar output reduction effect can be obtained simply by

(Self-Diagnosis Function) FIG. 26 shows a collision prevention device in which a self-diagnosis function is added to the third embodiment (FIG. 23). The receiving circuit 5 of FIG. 26 is adopted instead of the receiving circuit 5 of FIG. As a result, the self-diagnosis function can be added to the third embodiment.

Further, as described in connection with the self-diagnosis function of the first embodiment, it is also possible to adopt a configuration capable of detecting an abnormality in the reduced transmission output.

(Concrete operation at the time of crossing / merging) FIG. 27 shows a plurality of vehicles of Example 3 (FIG. 20) crossing at an intersection on a single-track traveling route, and FIG. ,
It is a figure which respectively shows. The transmission characteristics of this carrier are shown in FIG. As shown in FIGS. 27 (1) and 28 (1), the transport vehicles A and B approach the intersection, and the transport vehicle B further moves.
Carrier C is approaching from behind. At this point, the receiving coil 2 attached to the front side of each transport vehicle is not within the transmission range of the other transport vehicles, so other transport vehicles are not detected and are transmitted with normal transmission output. Continues to drive normally.

After a lapse of time, the receiving coil 2 of the transport vehicle B
Is within the transmission range of carrier A. Carrier B is carrier A
Is detected and stopped, and the output is reduced by the action of the output reduction circuit 4a. Further, the receiving coil 2 of the succeeding carrier C enters the reduced transmission output range of the carrier b, the carrier C also stops, and the output is reduced.
(2) The state shown in FIG. 28 (2) is obtained. Carrier A passes through the intersection without being affected by the reduced transmission of other carriers. When the receiving coil 2 of the transport vehicle B comes out of the transmission range of the transport vehicle A, the transport vehicle B returns to the normal transmission output and resumes traveling. When the receiving coil 2 of the carrier vehicle C comes out of the transmission range of the carrier vehicle B which has reached the normal transmission output and has resumed traveling, the carrier vehicle C also returns to the normal transmission output and resumes traveling.

FIG. 29 is a diagram showing how a plurality of transport vehicles cross each other on a double-track traveling route. As shown in FIG. 29 (1), carrier vehicles A, B, C and D are approaching an intersection. The receiving coil 2 of the carrier B is included in the transmission range of the carrier A, and the receiving coil 2 of the carrier C is included in the transmission range of the carrier D. Carriers B and C stop and reduce power. Carriers A and D are approaching.

After the passage of time, the transport vehicles A and D further approach each other, and the transmission / reception timings of the transport vehicles A and D are independently modulated. Therefore, the transport vehicle that first detected the other party stops. And reduce the output. As shown in FIG. 29 (2),
The receiving coil 2 of the carrier D enters the transmission range of the carrier A,
It is assumed that the transport vehicle D first detects the presence of the transport vehicle A. The transport vehicle D is stopped and the output is reduced. Carrier A passes downward at the intersection as seen in the figure. Among the remaining transport vehicles, the receiving coil 2 of the transport vehicle B is first out of the transmission range of the transport vehicle A. The carrier B returns the transmission output to the normal state and passes through the intersection. Next, the receiving coil 2 of the carrier vehicle D is out of the transmission range of the carrier vehicle B. The transport vehicle D returns the transmission output to the normal state and passes through the intersection. Finally, the carrier C passes through the intersection.

FIG. 30 shows a modification of the third embodiment (FIG. 2).
It is a figure which shows a mode that the conveyance vehicle of 3) crosses at an intersection on a double-tracked travel route. The transmission characteristic of this carrier is shown in FIG. In this case also, basically the same as in FIG. 29, but the order of priority is C, D, A, B. Here, after the transport vehicle D passes, it is the transport vehicle B that deviates from the transmission range of the transport vehicle D first, but the receiving coil of the transport vehicle B is in the reduced transmission range of the transport vehicle A. , The carrier A is given priority over the carrier B

In the prior art, a plurality of guided vehicles cannot move without stopping at the time of crossing or merging, but in the third embodiment, smoothing is achieved at the time of crossing / merging of single-track running routes and crossing / merging of multi-track running routes. It can be operated.

[Effects of the Embodiment] As described above, the collision preventing devices according to the first embodiment, the second embodiment, and the third embodiment can solve the following problems. (1) Both transport vehicles stop due to mutual interference in parallel traveling routes. (2) Both transport vehicles stop due to mutual interference at the time of merging and crossing. (3) Collisions between transport vehicles at the time of merging and crossing. (4) Collision due to the speed difference between the preceding and following vehicles. (5) A problem that the preceding carrier stops due to the interference of the following carrier.

Therefore, it is possible to prevent the collision between the transport vehicles safely and without an unnecessary stop by using only this device (standalone type). In addition, FIG.
Also, the directional characteristics as described with reference to FIG. 25 can be adopted.

The embodiments of the present invention have been described above. However, the technical scope of the present invention is not limited to the above embodiments. Although the embodiments have been described with respect to a carrier vehicle, the present invention can be applied to a carrier vehicle equipped with a collision prevention device regardless of manned or unmanned. As shown in FIG. 31, the concept of the present invention can be applied to an ultrasonic sensor. Moreover, as shown in FIG. 32, it can be applied to an infrared sensor. The technical scope of the present invention is determined based on the description of the claims.

[0137]

The transport vehicle to which the collision prevention device according to the present invention is attached secures a safe distance with only a single collision prevention device device, and both transport vehicles stop at a merge or intersection. Never.

Further, the carrier equipped with the collision prevention device according to the present invention can easily obtain the required directivity.

Further, the carrier vehicle to which the collision prevention device according to the present invention is attached may be a collision prevention device having a transmission characteristic different from the conventional transmission characteristic.

Further, the transport vehicle to which the collision prevention device according to the present invention is attached may be a collision prevention device having a self-diagnosis function capable of easily identifying a transport vehicle in which an abnormality has occurred.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an entire configuration of a first embodiment according to the present invention.

FIG. 2 is a diagram showing a timing chart of transmission and reception generated by the timing circuit of the first embodiment of FIG.

FIG. 3 is a diagram showing the timing of reducing the transmission output when a vehicle equipped with the collision prevention device according to the first embodiment of FIG. 1 merges with another vehicle.

FIG. 4 is a diagram showing an example of how the collision prevention device of the first embodiment shown in FIG. 1 is attached to a carrier vehicle.

5A and 5B are diagrams showing directivity characteristics of transmission and reception of the collision prevention device according to the first embodiment of FIG.

FIG. 6 is a diagram showing an operation at the time of merging of a carrier vehicle to which the collision prevention device according to the first embodiment of FIG. 1 is attached.

FIG. 7 is a diagram showing a transmission / reception timing at the time of merging of a carrier vehicle to which the collision prevention device according to the first embodiment of FIG. 1 is attached.

FIG. 8 is a modification of the first embodiment shown in FIG. 1 and is a diagram showing an overall configuration of a collision prevention device with a self-diagnosis function.

9 is a diagram showing the timing of the collision prevention device with a self-diagnosis function of the embodiment of FIG.

FIG. 10 is a diagram showing an overall configuration of a second embodiment according to the present invention.

FIG. 11 is a diagram showing directional characteristics (reception characteristics) when the coil of the collision prevention device according to the second embodiment of FIG. 11 is mounted horizontally.

FIG. 12 is a diagram showing directional characteristics (reception characteristics) when the coil of the collision prevention device according to the second embodiment of FIG. 10 is vertically attached.

FIG. 13 is a diagram showing transmission / reception timing at the time of merging of the collision prevention device according to the second embodiment of FIG. 10;

FIG. 14 is a diagram showing a state in which two transport vehicles equipped with the collision prevention device of the second embodiment of FIG. 10 pass each other on a parallel road.

FIG. 15 is a diagram showing a state in which two transport vehicles equipped with the collision prevention device of the second embodiment of FIG. 10 merge.

16 is a diagram showing a state in which two transport vehicles equipped with the collision prevention device according to the second embodiment of FIG. 10 intersect with each other.

FIG. 17 is a diagram for explaining an operation when a carrier vehicle equipped with the collision prevention device of the second embodiment of FIG. 10 is traveling on one traveling route and another carrier vehicle approaches from behind.

FIG. 18 is a diagram showing an operation when two transport vehicles equipped with the collision prevention device of the second embodiment of FIG. 10 are opposed to each other on one traveling route.

FIG. 19 is a diagram showing a modified example of the second embodiment of FIG. 10 and is a diagram showing an overall configuration of a collision prevention device with a self-diagnosis function.

FIG. 20 is a diagram showing an overall configuration of a third embodiment according to the present invention.

FIG. 21 is a diagram showing a state in which the collision prevention device according to the third embodiment of FIG. 20 is attached to a transport vehicle.

22 is a diagram showing the transmission characteristics of the loop antenna of Example 3 of FIG.

FIG. 23 is a diagram showing a modification of the third embodiment of FIG. 20.

FIG. 24 is a diagram showing a state in which the collision prevention device of the modified example of FIG. 23 is attached to a transport vehicle.

FIG. 25 is a diagram showing transmission characteristics of the modification example of FIG. 24.

FIG. 26 is a diagram showing a modification of the third embodiment shown in FIG. 20 and showing the overall structure of a collision prevention device with a self-diagnosis function.

FIG. 27 is a diagram showing how a plurality of carrier vehicles according to the third embodiment shown in FIG. 20 intersect at an intersection on a single-track travel route.

FIG. 28 is a diagram showing a state in which the plurality of carrier vehicles according to the third embodiment shown in FIG. 20 merge at an intersection on a single-track travel route.

FIG. 29 is a diagram showing how a plurality of carrier vehicles according to the third embodiment shown in FIG. 20 intersect at an intersection on a double-track travel route.

FIG. 30 is a diagram showing a state in which a plurality of carrier vehicles according to a modification of the third embodiment shown in FIG. 23 intersect at an intersection on a double-track travel route.

FIG. 31 is a diagram showing an overall configuration of a collision preventing device using ultrasonic waves according to another embodiment of the present invention.

FIG. 32 is a diagram showing an overall configuration of a collision prevention device using infrared rays according to another embodiment of the present invention.

FIG. 33 is a configuration diagram of a collision prevention device using an ultrasonic sensor of the related art.

FIG. 34 is a usage example of the collision prevention device using the ultrasonic sensor of the related art of FIG. 33.

FIG. 35 is a diagram for explaining a problem at the time of merging of a carrier vehicle to which the ultrasonic sensor of the related art of FIG. 33 is attached.

FIG. 36 is a diagram showing an overall configuration of a conventional collision prevention device using electromagnetic induction.

FIG. 37 is a diagram showing a specific example in which the collision prevention device using the electromagnetic induction of the conventional technique of FIG. 36 is attached to a transport vehicle.

38 is a diagram showing the directional characteristics (reception characteristics) of the collision preventing device using the electromagnetic induction of the conventional art of FIG.

FIG. 39 is a diagram for explaining a problem at an intersection of a carrier equipped with the conventional collision preventing device using electromagnetic induction of FIG. 36.

[Explanation of symbols]

 1 transmission (dedicated) coil 1a loop antenna 2 reception (dedicated) coil 3 transmission reception circuit 4 transmission circuit 4a output reduction circuit 4b output adjustment circuit 5 reception circuit 5a amplification detection circuit 5b (first) prohibition circuit 5c output circuit 5d coil Both-end voltage detection circuit 5e Second prohibition circuit 5f Third prohibition circuit 5g Comparison circuit 6 Stop signal 7 Timing circuit 7a Modulation circuit 7b Random number generator 8 Switching device 10,21 Ultrasonic wave transmitter 11,22 Ultrasonic wave detector 12 Infrared generator 13 Infrared detector 18 Device abnormal signal 21 Ultrasonic oscillator 23 Electronic circuit 24 Transmission range 25 Reception range 28 Overlapping range a1, a2 Moving contact b1, b2, c1, c2 Fixed contact T Basic cycle ΔT Random number Vth threshold Voltage

Claims (9)

[Claims] 1. A vehicle equipped with a collision prevention device, wherein the collision prevention device includes a transmission coil, a reception coil, a reception circuit that processes a signal from the reception coil and outputs a drive stop signal, and A transmission / reception circuit having a transmission circuit for transmitting a transmission signal to a transmission coil, and a timing circuit for outputting a timing signal to the reception circuit and the transmission circuit are provided, and the reception circuit detects its own transmission output, It has a self-diagnosis function that removes the reduced transmission output from the detection signal and outputs a device abnormality signal when the remaining detection signal is relatively low compared to the reference signal. And a carrier having means for randomly modulating a reception cycle. 2. The carrier vehicle according to claim 1, wherein the receiving circuit further includes a coil end voltage detection circuit, a second prohibition circuit, a third prohibition circuit and a comparison circuit, and the coil end voltage detection circuit. Detects the voltage of the receiving coil, the second prohibiting circuit nullifies the voltage across the coil corresponding to the transmission from another carrier based on the modulation signal from the timing circuit, and the third prohibiting circuit. The circuit nullifies the voltage across the coil corresponding to the transmission output of which the output is reduced, and the comparison circuit outputs the output of the third inhibition circuit to the third inhibition circuit corresponding to the normal transmission output of itself. The carrier vehicle that outputs a device abnormality signal when the output falls below the reference voltage as compared with a predetermined reference voltage relatively lower than the output. 3. The carrier vehicle according to claim 2, wherein the comparison circuit outputs a device abnormality signal for the first time when the output of the third prohibiting circuit falls below the reference voltage a plurality of times. 4. A vehicle equipped with a collision prevention device, wherein the collision prevention device processes a signal from the transmission loop antenna, a reception coil, and the reception coil, and outputs a drive stop signal. And a transmission / reception circuit having a transmission circuit for transmitting a transmission signal to the loop antenna, and a timing circuit for outputting a timing signal to the reception circuit and the transmission circuit, wherein the timing circuit includes a random number generator and a modulation circuit. A carrier vehicle having a transmission period and a reception period which are randomly modulated. 5. The vehicle according to claim 4, wherein the transmission circuit further includes a transmission output reduction circuit that reduces the transmission output in response to the output of the reception circuit, and the transmission output is reduced while the transportation vehicle is stopped. A carrier vehicle characterized by reduction. 6. The transport vehicle according to claim 4 or 5, wherein the prohibiting circuit disables the receiving function of the receiving circuit during its own transmission period in response to the modulation signal from the timing circuit. car. 7. The carrier according to any one of claims 4 to 6, wherein the receiving circuit further detects its own transmission output and removes the output reduced output from this detection signal, A carrier vehicle with a self-diagnosis function that outputs a device error signal when the remaining detection signal is relatively low compared to the reference signal. 8. The vehicle according to claim 7, wherein the receiving circuit further includes a coil end voltage detection circuit, a second prohibition circuit, a third prohibition circuit and a comparison circuit, and the coil end voltage detection circuit. Detects the voltage of the receiving coil, the second prohibiting circuit nullifies the voltage across the coil corresponding to the transmission from another carrier based on the modulation signal from the timing circuit, and the third prohibiting circuit. The circuit invalidates the voltage across the coil corresponding to the transmission output of which the output is reduced, and the comparison circuit relatively lowers the output of the third prohibition circuit than the output corresponding to the normal transmission output of itself. A carrier vehicle that outputs an apparatus abnormality signal when the output of the third prohibiting circuit falls below the reference voltage a plurality of times compared with a predetermined reference voltage. 9. A vehicle equipped with a collision prevention device, the collision prevention device including a transmission loop antenna, a reception coil, and a reception circuit that processes a signal from the reception coil and outputs a drive stop signal. And a transmission / reception circuit having a transmission circuit that transmits a transmission signal to the loop antenna, and a timing circuit that outputs a timing signal to the reception circuit and the transmission circuit to randomly modulate a transmission cycle and a reception cycle, Further, a transmission coil connected to the transmission circuit is provided, a part of the loop antenna is wound on the transmission coil in an overlapping manner, and both ends of the loop antenna are connected to switch means, and the switch means is connected to the output reduction circuit. The switching signal of the above-mentioned loop antenna operates so that it is closed during the period when the transmission output is reduced and opened during the normal period when the transmission output is reduced. Transport vehicle, characterized in that changing the transmission range of al in a substantially circular shape.