JPH035607B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and device for guiding an unmanned trolley by automatically controlling the direction when the unmanned trolley moves along a guidance zone if the unmanned trolley deviates from its direction. .

An unmanned trolley refers to a trolley that has a power source on it and is able to run automatically.Currently, devices that enable unmanned running are used in peripheral equipment of automated warehouses, goods transport equipment on production lines, and automated trolleys. It is widely used in conveyance equipment in processing lines, etc., and its feature is that it does not have dedicated rails. The fact that it does not have a dedicated rail means that
It is advantageous in that it can run on general factory corridors, allowing it to use space shared with forklifts and people, and that it is easy to change its travel route.

Conventionally, electromagnetic induction methods and optical guidance methods have been put into practical use as driving methods for unmanned trolleys.

In the electromagnetic induction method, as shown in Fig. 1, the running surface a
A pair of detectors d and d attached to the trolley c detect the induced magnetic field generated by passing a current through the guiding wire b embedded in the floor of the trolley c, and the running direction is controlled so that the detected strength is the same. This allows the trolley to run along the guide line. That is, the guide line b embedded in the running surface a
When a current is passed through, an induced magnetic field e is generated, and the system runs while detecting this induced magnetic field e with a pair of detectors d and d, and the center of the detectors d and
If it deviates in either direction, there will be a difference in the intensity detected by the detectors d and d, so by controlling the running direction of the cart so that the difference becomes zero, the cart can be moved along the guide line b. It is designed so that you can do it.

In addition, in this electromagnetic induction method, when guiding the trolleys to branch or merge along a complicated route, the current flowing through the guide wire b is made into an alternating current with a different frequency for each route, and at the point where they intersect, There is a system in which the frequency of the next route to be traveled is sent to the bogies from the ground, thereby causing the bogies to branch or merge. That is, as shown in FIG. 2, when moving the bogie c to point A, by giving a command to the bogie c at the branch point f to run along the guide line _b1 of the frequency _F1 , the bogie c can be moved to point A following guide line b ₁ , and when moving a trolley traveling on guide line b ₁ at branch point g,
If a command is given to the bogie to run along the guide line of frequency _F2 , the bogie will branch to point B along the guide line _b2 . Methods of transmitting command signals to the bogies at each branch point include transmitting signals from the ground using radio, light, or sound waves, or burying multiple coils in one place under the running road surface, excitation of each coil,
There is a method in which a certain pattern is displayed by de-energizing, and the truck detects this pattern and issues a travel command. In addition, there is a method in which the frequencies of the guide wires are all the same, and the route is sequentially switched as the cart advances to guide the cart.

However, this guidance method has the following problems.

Since the guide wire b needs to be buried under the running road surface, the installation work is complicated, and it is also difficult to relocate or change the route, discover and repair breaks in the guide wire b, and so on.

Induction power supplies with different frequencies and electrical work are required, and the control equipment for the route the bogie travels is complicated.

The guide wire breaks due to subsidence of the running surface a, sudden vibration, etc.

Because the magnetic field is adversely affected by electrical conductors near the guide wire, there are many restrictions on the structure of the road surface. For example, on a reinforced concrete floor, etc., the reinforcing bars and guide wires need to be separated by a certain value or more, so the distance between the running surface and the reinforcing bars needs to be larger than necessary.

Since there is a practical upper limit to the strength of the induced magnetic field,
The allowable deviation limit between the car body and the induction body is small.

Next, in the optical guidance method, a light reflector is installed on the floor of the running surface, the light emitted from the bogie is reflected by this light reflector, and the bogie is guided by detecting the relative position of the reflected light and the bogie. This is a method to do so.

That is, as shown in FIG. 3, light emitted from a light source h provided on the side of the truck c is reflected by a reflector i on the running surface a, and the reflected light is reflected from the truck c depending on the position of the light receiving section j that detects the reflected light. This method detects the relative relationship of body i and controls the running direction of the truck according to the amount of deviation. k is a running wheel.

In this method, as shown in FIG. 4, when the light emitted from the light source h is detected at the left side of the light receiving section j,
Since the bogie c has shifted to the right side of the reflector i, a running direction correction command is given to the bogie c according to the amount of deviation, and the trajectory is corrected so that the bogie c moves to the left side.

Other optical methods include a method in which the amount of reflection from a reflector is detected by a pair of light receiving sections, and the positions are controlled so that the amounts of reflection are the same.

When using such an optical guidance method to branch or merge the trolley c along a complicated route, there are various methods such as providing a dedicated light receiving section for left and right branching and for straight running. As a command signal to the bogie at each branch point, there are methods of transmitting signals from the ground using radio, light, sound waves, etc., or a method of installing another reflecting part near the guiding reflection and receiving the reflected light with the light receiving part. However, there is a method in which a driving command is issued by detecting the pattern.

However, these optical guidance systems have the following problems.

(1) Light reflection is likely to be inhibited by dust etc. adhering to the derivative.

(2) Light reflection is easily inhibited by damage to the dielectric surface.

(3) If the running surface is uneven, it is difficult to install reflectors and even those that are installed are likely to peel off.

As mentioned above, both the conventional electromagnetic induction method and the optical induction method have many problems. The installation method is complicated.

The present invention solves these conventional problems and allows the cart to be guided along the guide zone, and also allows the cart to run in any direction or merge in any direction even where the guide zone diverges. This was done in an attempt to change the polarity of the magnetic detection element of the magnetic detection sensor installed on the trolley from N to S and vice versa.
The system is designed to guide and control the bogie along guidance zones defined as poles and south poles, and also control the speed of the bogie.

Embodiments of the present invention will be described below with reference to the drawings.

5 to 9 show the basic configuration of the present invention, in which a magnetic guide band 1 extending in the direction in which the unmanned vehicle is to run is laid on the running surface 2,
On the other hand, the unmanned trolley is equipped with left and right running drive wheels 4 in the center of the trolley 3 so as to be driven by independent running drive motors 5, as well as left and right driven wheels 6 at the front and rear. It has a configuration in which magnetic detection sensors 7 and 7' are attached to the front and rear ends of the lower surface of the computer, and further includes a computing device 9 connected to the magnetic detection sensors 7 and 7'. A travel drive control device 1 that issues a command to control the rotation of the travel drive motor 5 based on the calculated value.
0, and other batteries are mounted on the trolley 3, so that the trolley 3 can be guided along the guide zone 1 unmanned.

The magnetic detection sensors 7, 7' are composed of a large number of magnetic detection elements 8, and each magnetic detection element 8 has a magnetic field 11 (the seventh
8) and at a predetermined pitch in the left-right direction of the trolley 3, each magnetic detection element 8 is connected to an arithmetic unit 9.
When any magnetic detection element 8 detects magnetism, the address corresponding to that element 8 is displayed, and at the same time, the address corresponding to the displayed address is displayed. The distance between the reference position and the address is calculated by the arithmetic unit 9.

The feature of the present invention is that the following configuration is added to the above-mentioned basic configuration, so that the cart 3 can be easily guided in a desired direction at a branch point of the guide zone 1.

That is, the induction band 1' is branched from the middle of the induction band 1, and the polarity of the branched induction band 1' is changed to the polarity of the induction band 1.
shall be different from the polarity of On the other hand, a polarity switching magnetic sensor 12, 12' for switching the polarity of the guiding magnetic detection sensor 7, 7' is provided at the front end of the truck 3.
2' is controlled to operate by the magnetic elements 14, 14' installed on the running surface 2 in front of the branch point 13, the signals from the magnetic sensors 12, 12' activate the magnetic detection sensors 7, 7'. Polarity can be switched. If there is no need for branching, use the magnetic sensor 12,
12' is controlled so as not to operate. The polarity of the magnetic detection sensors 7, 7' is switched by reversing the coil characteristics of the magnetic detection element 8.
FIG. 11 is a block diagram of the polarity switching control of the magnetic detection sensors 7, 7', in which an output circuit 15 is connected to the magnetic detection element 8 of the magnetic detection sensors 7, 7', and sensor 12,
12' is connected to the polarity changeover switch 16, which is changed over by a signal from the polarity changeover switch 16.
By switching, the coil characteristics of the magnetic detection element 8 are reversed, so that the polarity can be switched from N pole to S pole and vice versa. 17 is an output amplifier, 1
8 is an element operating circuit leading to the arithmetic unit 9.

In addition, in FIG. 10, 19 and 19' are magnetic generating bodies installed on the running surface 2 along the induction zone 1, and 20 and 20'
is a magnetizing body having a polarity different from that of the inductor 1, and is installed near the inductive band 1 or overlapping the inductor 1, and is used to control the speed of the bogie 3.

When guiding the trolley 3 along the guide zone 1, it can be guided while being controlled so that the center of the truck 3 and the center of the guide zone 1 are automatically aligned. Now, for example, magnetic detection sensor 7, 7'
Assuming that the center of the magnetic detection element 8 coincides with the center of the induction band 1,
As long as the several magnetic detection elements 8 in the center of the magnetic detection sensors 7, 7' detect the magnetism of the induction band 1, and this is displayed as the address in the center in the arithmetic unit 9, the arithmetic unit 9 recognizes the carriage. Since the deviation amount of 3 is calculated as zero, the trolley 3 is run in a state where the center C of the detection sensors 7, 7' and the center of the guide band 1 are aligned.

For example, if the truck 3 deviates to the right side while traveling, the center C of the magnetic detection sensor 7 provided on the truck 3 detects the magnetic field of the induction band 1. will be detected. Now, the distance between the center C of the magnetic detection sensor 7 and the n _- th magnetic detection element 8 sensing magnetism is l ₁ , and the distance between the center C and the n _- th magnetic detection element 8 is also l 1 . The distance L from the center C of the magnetic detection sensor 7 to the center line of the induction zone 1 is expressed as L=l ₁ +l ₂ /2, and this distance L is the distance from the induction zone ₁ . This is the amount of deviation.

Since the magnetic detection elements 8 from the nth _first to the _nth second detect magnetism, the arithmetic unit 9
Then, the addresses from the nth _1st to the nth _2nd address are displayed, and the calculation of L=l ₁ +l ₂ /2 is performed to move to the right or left with respect to the center C of the magnetic detection sensor 7. The actual amount of deviation is determined. Once the amount of deviation is determined, a control command that makes the amount of deviation zero is sent from the travel drive control device 10 to the travel drive motor 5.
The rotation of the left and right drive wheels 4 is controlled to control the direction of the truck. Signals are fed back from the travel drive motor 5 to the travel drive control device 10 and the arithmetic unit 9, and direction control is performed until the amount of deviation becomes zero, so that the center of the magnetic detection sensor 7 of the bogie 3 is the center of the guide band 1. The trolley 3 can be automatically guided to match the .

In the unmanned guidance of the trolley 3, the detection polarity of the magnetic detection sensors 7, 7' is set to one pole (for example, N
If the polarity of the induction band 1 is limited, the polarity of the induction band 1 must also be limited accordingly. However, in this case, in order to branch the trolley 3 at the branch point 13, various complicated guidance mechanisms for branching (including a branch-specific guidance program in an arithmetic unit, etc.) are required.

In the present invention, the polarity of the branched induction band 1' is made different from the polarity of the induction band 1, and the polarity of the magnetic detection sensors 7, 7' can be freely switched. Even if there is only a difference, the trolley 3 can be easily branched. That is, when the truck 3 is branched at the branch point 13, the polarity switching magnetic sensors 12, 1 provided on the truck 3 are
2' is activated in advance, the magnetic sensors 12, 12' for polarity switching are activated by the magnetizing elements 14, 14' installed on the running surface 2, and this signal causes the polarity switching as shown in FIG. When the switch 16 is switched, the polarity of the magnetic detection element 8 is switched from the N pole to the S pole, and the bogie 3, which had been guided by the polarity (N pole) of the induction band 1, changes to a different polarity (S pole) at the branch point 13.
The vehicle is caused to run along a guide band 1' having a pole), and is guided along the guide band 1' in the same manner as in the case of the guide band 1 described above. The same applies to the case of merging.

In this way, if the polarity of the magnetic detection sensors 7, 7' is switched to the south pole at the branch point 13, the cart will move in the direction of the guide band 1, and if it is switched to the north pole, the cart will move in the direction of the guide band 1'. be able to.

In the present invention, since the polarity of the magnetic detection sensors 7, 7' of the truck 3 can be changed as described above, the following control can also be performed.

That is, magnetizing bodies 20 and 20' having a polarity different from that of the induction band 1 are installed near the induction band 1 or overlapping the induction band 1, and a magnetizing body 19 is placed on the running surface 2 in front of the magnetic generating body 20. , 19' are installed, and when the polarity switching magnetic sensors 12, 12' are activated by the magnetizing bodies 19, 19', the polarity of the magnetic detection element 8 of the magnetic detection sensor 7, 7' is switched, and the polarity is switched. Speed control can be performed without being influenced by the polarity of the induction band 1 by the number of magnetic detection elements 8 that emit ON signals at the magnets 20, 20'. Now, for example, the element 8 of the magnetic detection sensor 7 is turned on by the magnetizing body 20' of length y.
If the length of the
If acceleration is determined, deceleration occurs if the length during which the element 8 of the magnetic detection sensor 7 is ON due to the magnetizing body 20 of length x is greater than or equal to x' and less than or equal to y' as shown in FIG. The magnetic detection sensor 7 is a magnetic body 20,
When approaching 20', the speed of the truck can be freely controlled.

In addition to the method of installing the guide strips 1 and 1' directly on the running surface, it is also possible to provide a recess in the running surface 2 and install the guide strip 1 or 1' in the recess as shown in Fig. 14. Alternatively, as shown in FIG. 15, a thin guide strip 23 may be installed on the floor material 21 and the floor 22, and various installation methods can be adopted depending on the appearance and lifespan of the guide strip. Of course, various changes can be made without departing from the gist of the invention.

As described above, according to the present invention, a magnetic induction band and a magnetic detection sensor having a large number of magnetic detection elements are combined, and the polarity of the magnetic detection sensor can be switched between N pole and S pole. Therefore, the following excellent effects can be achieved.

(i) Even if the guidance band is branched, by simply changing the polarity depending on the route, it is possible to easily make the bogie run in a branched manner by simply switching the polarity of the magnetic detection sensor used to guide the bogie. .

(ii) Since the polarity of the magnetic detection sensor can be switched and used, induction control and speed control can be performed by installing a magnet with a polarity different from that of the induction band.

(iii) The amount of deviation from the center of the guide band can be detected regardless of the width of the guide band.

(iv) Installation and relocation of the induction strip is easy, and the induction strip is not affected by magnetic material existing under the installation surface, and magnetism remains even if the induction strip surface is damaged. It also has the advantage of not having a negative effect on guidance as long as possible.

[Brief explanation of the drawing]

Figures 1 to 4 are schematic diagrams showing conventional systems;
FIG. 5 is a schematic plan view showing the basic configuration of the device of the present invention, FIG. 6 is a side view of FIG. 9 is a block diagram of the device of the present invention, FIG. 10 is a plan view showing the features of the present invention, and FIG. 11 is a control for switching the polarity of the magnetic detection sensor provided on the trolley. FIGS. 12 and 13 are block diagrams of other control procedures according to the present invention, and FIGS. 14 and 15 are other examples of guide band installation methods. 1, 1'...Guidance band, 3...Dolly, 4...Traveling drive wheel, 7,7'...Magnetic detection sensor, 8...
Magnetic detection element, 9... Arithmetic device, 10... Travel drive control device, 12, 12'... Magnetic sensor for polarity switching, 14, 14'... Magnetizing body, 15... Output circuit, 16... Polarity switching Switch, 19, 19',
20, 20'... Magnetizing body.

Claims (1)

[Scope of Claims] 1. In a method for guiding an unmanned trolley in which the bogie runs along a guide zone, the bogie is moved while detecting the magnetism of the guide strip, and a magnetic detection sensor is activated at a branching point or a confluence point of the guide strip. A method for guiding an unmanned trolley characterized by switching the polarity and guiding the trolley to a route with a different polarity from a branching point or a confluence point. 2. A magnetic detection sensor having a large number of magnetic detection elements arranged thereon is attached to the cart, and a polarity switching magnetic sensor is attached to the cart, which is activated by a magnetic body installed on the running surface to switch the polarity of the magnetic detection sensor, and the above-mentioned The bogie is equipped with a device that controls the running drive part of the bogie using signals from magnetic detection elements, and the polarity of the guide strips installed on the running surface, which branch and merge from branching points and merging points, is different for each route. A guidance device for an unmanned trolley, which is characterized by: