JP4131706B2 - Travel stop control device for automatic guided vehicles - Google Patents

Description

  The present invention relates to a travel stop control device for an automatic guided vehicle in an automatic guided system used in a factory or an automatic warehouse.

  2. Description of the Related Art Conventionally, unmanned transport systems that perform operations such as baggage transport by running control of automatic guided vehicles have been provided in factories and automatic warehouses. FIG. 7 shows a schematic configuration diagram of the automatic transfer system, and the automatic guided vehicle 1 travels while exchanging signals and data with the ground control panel 3 along the guide line 2 embedded in the floor surface. However, the automatic guided vehicle 1 stops at the position of the conveyor 4, and loads are exchanged between the automatic guided vehicle 1 and the conveyor 4.

  The automatic guided vehicle 1 needs to recognize which position on the guide line 2 is traveling, and therefore includes a non-contact type recognition device. As shown in FIGS. 7 and 8, the non-contact type recognition device includes a recognition card 5 embedded in the floor along the guide line 2, and an antenna 6 attached to the lower surface of the automatic guided vehicle 1. It consists of For example, Japanese Patent Application Laid-Open No. H10-228707 includes a non-contact type recognition device that includes the recognition card 5 and the antenna 6.

JP-A-7-93031

  The non-contact type recognition device for recognizing the current position of the automatic guided vehicle 1 in this automatic guided system has the antenna 6 on the automatic guided vehicle 1 side and the recognition card 5 on the ground side to be detected as described above. The antenna 6 for supplying power to the recognition card 5 is substantially rectangular and is larger than the recognition card 5 as shown in FIG. The antenna coil of the antenna 6 is wound in the circumferential direction, and power is supplied to the recognition card 5 by a high-frequency magnetic field generated by a current flowing through the antenna 6. By receiving power from the antenna 6 on the recognition card 5 side, recognition data as location data is sent from the recognition card 5 to the antenna 6 side. The automatic guided vehicle 1 side can recognize the current position from the recognition data received from the recognition card 5.

  The recognition card 5 has a structure as shown in FIG. 10, for example, and receives a high frequency magnetic field from the antenna 6 to supply power to each part, and a position where the recognition card 5 is embedded. The data section 52 stores data in advance, and the transmission section 53 transmits position data from the data section 52 to the antenna 6 of the automatic guided vehicle 1.

  When the automatic guided vehicle 1 travels and the antenna 6 comes near the recognition card 5 or on the recognition card 5, power is supplied from the antenna 6 to the recognition card 5, and recognition data (position data) is received from the recognition card 5. ) Is transmitted to the antenna 6. This operation is performed until the automatic guided vehicle 1 is traveling and the antenna 6 is separated from the recognition card 5. In this way, the automatic guided vehicle 1 can recognize the current position every time it travels on the recognition card 5 and can recognize position information as an absolute position.

  In this way, when the antenna 6 of the automatic guided vehicle 1 can supply the necessary power to the recognition card 5 side, the data from the recognition card 5 can be received by the automatic guided vehicle 1 side. Although the current position can be recognized in a range having a width of about the size of the antenna 6, it can be used for control that requires detection position accuracy such as stop control of the automatic guided vehicle 1 using the recognition card 5. There wasn't. That is, the range in which the antenna 6 can receive power from the antenna 6 to the recognition card 5 and receive the position data from the recognition card 5 has a width in the traveling direction of the antenna 6. It was not possible to make the center of the two coincide with each other, and it could not be used for stop control or the like. For this reason, another stop position detection means is required to accurately perform stop control of the automatic guided vehicle 1. In addition, there is a problem that a separate construction is required and the cost increases as a whole.

  In Patent Document 1, in order to perform stop control with high accuracy, two coils are required on the recognition card 5 side in addition to the power supply induction coil, which increases costs and increases the existing recognition card. There is a problem that it cannot be applied to 5, and if it is applied, it must be reconstructed.

The present invention is provided in view of the above-described problems, and provides a travel stop control device for an automatic guided vehicle having at least the following objects.
(1) By using an antenna for detecting the current position on the automatic guided vehicle side, the automatic guided vehicle is accurately stopped without using another stop detection means.
(2) The present invention is applicable to existing non-contact type recognition cards, and improves the stopping accuracy of the automatic guided vehicle without re-installing the recognition card.
(3) The automatic guided vehicle can be stopped with high accuracy and the increase in cost as a whole can be suppressed.

Therefore, in the travel stop control device for the automatic guided vehicle of the present invention, the recognition card disposed on the traveling road surface, and the antenna that is attached to the automatic guided vehicle traveling on the traveling road and supplies electric power to the recognition card by a magnetic field. In the unmanned conveyance system in which the position data stored in advance from the recognition card that receives power supply from the antenna is transmitted to the antenna to recognize the current position on the automatic guided vehicle side,
Two antennas for power supply arranged in parallel along the traveling direction of the automatic guided vehicle, an antenna power supply unit for supplying current so that a magnetic field in the same direction is generated from both antennas, and a position from the recognition card A control means for causing a current to flow so that the magnetic field generated from the one antenna is reversed when data is received, and for stopping running when position data from the recognition card is no longer received. It is a feature.

  According to the traveling stop control device of the automatic guided vehicle of the present invention, when the center of the two antennas where the magnetic fields cancel each other comes to the center of the recognition card, the power cannot be supplied to the recognition card, and the data from the recognition card cannot be supplied. Since the automatic guided vehicle is controlled to stop when the vehicle cannot be received, the automatic guided vehicle can be accurately stopped without using a separate stop detection means. Therefore, it can also be applied to existing non-contact type recognition cards, can improve the stopping accuracy of automatic guided vehicles without re-installing the recognition cards, and can be used for unattended transport using an antenna for detecting the current position. The vehicle can be stopped with high accuracy, and an increase in cost can be suppressed as a whole.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention devised on the antenna side for detecting the current position of the automatic guided vehicle so as to stop the automatic guided vehicle accurately without using a separate stop detecting means. The same number is attached | subjected to the element which exhibits a function, detailed description is abbreviate | omitted, and the part of a summary is explained in full detail.

  That is, as shown in FIGS. 1 to 3, the conventional antenna is divided into two antennas 10a and 10b, and the antenna 10a is arranged in the running direction of the automatic guided vehicle. 10b are arranged side by side. Then, as shown in FIG. 2, a circuit that passes current so that a magnetic field in the same direction is generated and a circuit that passes current so that a magnetic field in the opposite direction is generated as shown in FIG. It is possible to switch. In FIG. 3, the current on the antenna 10a side is reversed, but the current on the other antenna 10b side may be reversed.

  The antenna coils of the two antennas 10a and 10b arranged in parallel are wound in the circumferential direction, and the current flowing through the antennas 10a and 10b is in the same direction as the winding direction of the antenna coils. Normally, as shown in FIG. 2, currents flow in the same direction in both antennas 10 a and 10 b, and the portions where both antennas 10 a and 10 b are in contact with each other cancel each other, so that it appears as one antenna. The position data from the recognition card 5 can be read within the range.

  The automatic guided vehicle 1 travels in the state shown in FIG. 2 in the direction of the current flowing through the antennas 10a and 10b, power can be supplied from the antenna 10a of the automatic guided vehicle 1 to the recognition card 5, and the position from the recognition card 5 When data is received, the direction of the current flowing through the antenna 10a is switched to the opposite direction as shown in FIG. Then, the automatic guided vehicle 1 travels in that state.

  FIG. 4 is a block diagram of the automatic guided vehicle 1 side. The position data received from the recognition card 5 is input by the data input unit 21 input from both antennas 10a and 10b, and the position data from the data input unit 21 is unattended. A data recognition unit 22 for recognizing the current position of the transport vehicle 1, an antenna power supply unit 26 for supplying current to both antennas 10a and 10b, and an antenna power supply unit 26 and one antenna 10a are interposed. The polarity switching unit 27 that switches the polarity of the current that flows through the antenna 10a and the polarity switching unit 27 that controls the polarity switching unit 27 with a signal that the position data from the data recognition unit 22 has been received. A control unit 23 that performs switching control of the polarity and performs overall control, a travel motor drive unit 24 that drives a travel motor 25 for travel of the automatic guided vehicle 1, and the like. It has been.

  Here, as will be described later, in order to stop the automatic guided vehicle 1 when the center of both antennas 10a and 10b and the center of the recognition card 5 coincide, the data from the data recognition unit 22 is sent to the control unit 23. When input, the control unit 23 controls the traveling motor driving unit 24 to decelerate the automatic guided vehicle 1.

  Next, stop control of the automatic guided vehicle 1 will be described. The state shown in FIG. 5A is when the automatic guided vehicle 1 is traveling along the guide line 2 and the antennas 10a and 10b of the automatic guided vehicle 1 are approaching the recognition card 5 and the antennas 10a and 10b. In this state, power is not supplied to the recognition card 5. In the state of FIG. 5 (a), the directions of the currents flowing through both antennas 10a and 10b are the same. As described above, the currents cancel each other at the portion where both antennas 10a and 10b are in contact with each other. It becomes an antenna, and the position data from the recognition card 5 can be read within the range.

  Next, when the antenna 10 approaches the recognition card 5 and receives a position from the recognition card 5, the control unit 23 controls the polarity switching unit 27 as shown in FIG. Switch the polarity of the current to flow in reverse. In this state, the direction of current flowing through both antennas 10a and 10b is reversed (the winding direction of both antenna coils is reversed). Further, the control unit 23 controls the traveling motor driving unit 24 to decelerate the automatic guided vehicle 1. Further, the automatic guided vehicle 1 travels, and as shown in FIG. 5 (c), the portion where both antennas 10a and 10b are in contact (the central portion of the antenna 10) is the position above the recognition card 5 and the recognition card. 5 is deviated from the center of 5 to the left and right, even if the magnetic fields cancel each other at the part where both antennas 10a and 10b are in contact, the power can be supplied from the end of the antenna 10a close to the recognition card 5. When the card 5 is within the width range of the antenna 10a and the antenna 10b, the data of the recognition card 5 can be read by the magnetic field from each antenna 10a, 10b.

  As the automatic guided vehicle 1 further travels and the direction of the generated magnetic field is opposite as shown in FIG. 6A, the portions where the antennas 10a and 10b are in contact with each other (the center of the antenna 10) Portion) comes to the center of the recognition card 5, the ends of both antennas 10a, 10b are also away from the recognition card 5, so that no power can be supplied to the recognition card 5 from the antennas 10a, 10b. The antennas 10a and 10b cannot receive the position data from the recognition card 5. At the position where the position data can no longer be received, the control unit 23 controls the traveling motor driving unit 24 to stop and stops the automatic guided vehicle 1.

  And after stopping the automatic guided vehicle 1, the control part 23 controls the polarity switching part 27, and returns the direction of the electric current sent through the antenna 10a (refer FIG.6 (b)), antenna 10a, Power can be supplied to the recognition card 5 from 10b, and position data can be received again from the recognition card 5, so that the automatic guided vehicle 1 can recognize the current position. In this way, the automatic guided vehicle 1 can be stopped when the center of the antenna 10 and the center of the recognition card 5 overlap.

  As described above, in the present embodiment, the direction of the current flowing through the antennas 10a and 10b arranged side by side is normally set to the direction in which the magnetic field in the same direction is generated, and one (front part) is received when data from the recognition card 5 is received. When the current flowing through the antenna 10a is reversed, the antennas 10a and 10b arranged in parallel generate a magnetic field in the opposite direction, and the center of the antennas 10a and 10b where the magnetic fields cancel each other comes to the center of the recognition card 5. In addition, the automatic guided vehicle 1 is controlled to stop when power cannot be supplied to the recognition card 5 and data cannot be received from the recognition card 5, so that the automatic guided vehicle can be used without using a separate stop detection means. 1 can be accurately stopped. Therefore, it can also be applied to existing non-contact type recognition cards, can improve the stopping accuracy of automatic guided vehicles without re-installing the recognition cards, and can be used for unattended transport using an antenna for detecting the current position. The vehicle can be stopped with high accuracy, and an increase in cost can be suppressed as a whole.

It is a block diagram of the non-contact-type recognition apparatus in embodiment of this invention. It is explanatory drawing at the time of flowing an electric current so that a magnetic field may generate | occur | produce in the same direction in two antennas in embodiment of this invention. It is explanatory drawing at the time of flowing an electric current so that a magnetic field may generate | occur | produce in the reverse direction in one antenna in embodiment of this invention. It is a block diagram of the automatic guided vehicle in embodiment of this invention. (A)-(c) is explanatory drawing in the case of carrying out stop control of the automatic guided vehicle in embodiment of this invention. (A) (b) is explanatory drawing in the case of carrying out stop control of the automatic guided vehicle in embodiment of this invention. It is a schematic block diagram of an unmanned conveyance system. It is a block diagram of the non-contact-type recognition apparatus of a prior art example. (A) (b) is explanatory drawing of the non-contact-type recognition apparatus of a prior art example. It is a block diagram of a recognition card.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic guided vehicle 5 Recognition card 10, 10a, 10b Antenna 23 Control part 24 Driving motor drive part 26 Antenna power supply part 27 Polarity switching part

Claims (1)

A recognition card disposed on the road surface, and an antenna that is attached to an automatic guided vehicle that travels on the road and supplies electric power to the recognition card with a magnetic field. In the unmanned transport system that transmits the position data stored in advance to the antenna and recognizes the current position on the unmanned transport vehicle side,
Two antennas for power supply arranged in parallel along the traveling direction of the automatic guided vehicle, an antenna power supply unit for supplying current so that a magnetic field in the same direction is generated from both antennas, and a position from the recognition card A control means for causing a current to flow so that the magnetic field generated from the one antenna is reversed when data is received, and for stopping running when position data from the recognition card is no longer received. A feature of a travel stop control device for an automatic guided vehicle.

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