JPH04111105A - Sensor device for unmanned carrier - Google Patents

Abstract

PURPOSE:To surely actuate a magnetic contactless switch and to improve both the reliability and the working ratio of an unmanned carrier system by eliminating automatically the iron pieces and powder dropped on the surface of a driving path of the carrier with small consumption of current. CONSTITUTION:The iron pieces/powder 9 may possibly be dropped on the surface 6 of a driving path of an unmanned carrier 1 in a factory, etc. If the carrier 1 is driven under such conditions, the iron piece/powder 9 are attracted by a permanent magnet 11. Thus the carrier 1 detects a position detecting mark plate 7 in a collection pit 10 and stops before a contactless switch 8 set on the surface 6 becomes inefficient owing to those stacked pieces/powder 9. At the same time, an energizing command of a short time is given to a coil 23 of a permanent electromagnet 11. Thus the electromagnet 11 is demagnetized and the pieces/powder 9 drop into the pit 10 to be taken away.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sensor device for controlling an unmanned vehicle.

[Conventional technology]

As described in Japanese Utility Model Application Publication No. 63-107007, magnetic proximity switches (reed switches) are used as sensors for controlling intersections, traffic lights, automatic doors, etc. for unmanned vehicles. There is. This is buried in the road surface on which the unmanned vehicle travels, and when a permanent magnet provided on the underside of the unmanned vehicle comes directly above it, it is activated by the magnetic force of the permanent magnet to perform the above-mentioned control. Even at this time, there is a certain distance (50 to 70 mm) between the permanent magnet and the magnetic proximity switch, so the magnetic force of the permanent magnet needs to be strong.

In addition to the magnetic proximity switch, a mark plate for an operation control sensor separately provided on the underside of the unmanned vehicle is embedded in the road surface on which the unmanned vehicle runs. A magnetic sensor may be used as this sensor, in which case a permanent magnet is used as the mark plate.

[Problem to be solved by the invention]

When an unmanned vehicle is used in a factory or the like, pieces of iron and iron powder often fall on the road surface. As mentioned above, the magnetic force of the permanent magnet that operates the magnetic proximity switch is strong, and therefore iron pieces and iron powder are attracted to and deposited on this magnet while the unmanned vehicle is running. This may weaken the magnetic force of this magnet, making it impossible to operate the control magnetic proximity switch. As a result, various controls of unmanned vehicles may become impossible, and there is a possibility that unmanned vehicles will collide with each other at intersections.

Therefore, it is necessary to periodically remove the iron pieces and iron powder that are attracted to the magnets on the underside of the unmanned vehicle, as well as the iron pieces and iron powder that have fallen onto the driving road surface, which only requires time and effort. In addition, the unmanned vehicle system is stopped and the operation rate of the unmanned vehicle system is reduced.

Even if iron pieces and iron powder are attracted and deposited on the permanent magnet, in order for the permanent magnet to reliably operate the magnetic proximity switch, the magnetic force of the permanent magnet must be made even stronger. As a result, there is a risk that the magnetic force of the mark plate buried in the road surface for activating the above-mentioned operation control sensor may be canceled and the position may be misidentified.

In addition, in order to prevent the iron pieces and iron powder from being attracted to the permanent magnet, this magnet can be used as an electromagnet to generate magnetic force by applying current only when necessary, but as mentioned above, the magnetic force of this magnet is , it is necessary to have a certain degree of strength, and in order to obtain this magnetic force, a large amount of current is consumed, and the battery of the unmanned vehicle becomes large, and the main body becomes large accordingly.

The purpose of the present invention is to automatically remove iron pieces and iron powder that have fallen onto the road surface with low current consumption.
It is an object of the present invention to provide a sensor device for an unmanned vehicle that reliably operates a magnetic proximity switch.

[Means to solve the problem]

To achieve the above-mentioned object, the present invention provides a magnetic proximity switch that is provided on the underside of the unmanned vehicle and placed in either a magnetic state or a demagnetized state in order to operate a magnetic proximity switch buried in the road surface of the unmanned vehicle. and a control means for switching the magnetic force of the permanent electromagnetic magnet in order to remove iron pieces or the like that are attracted to the permanent electromagnetic magnet during operation of the unmanned vehicle. A sensor device for an unmanned vehicle is provided.

[For production]

If the magnetic force of the permanent electromagnetic magnet is demagnetized by the control means before the iron pieces and iron powder that are attracted to the permanent electromagnetic magnet from the road surface while the unmanned vehicle is running accumulate and weaken the magnetic force of the magnet. ,
Iron pieces, iron powder, etc. can be removed. Thereafter, by returning the permanent electromagnetic magnet to a constant magnetic state again by the control means and driving the unmanned vehicle, the magnetic proximity switch embedded in the road surface can be reliably activated.

〔Example〕

In FIG. 1, 1 indicates an unmanned vehicle, and 2 indicates a motor that drives the unmanned vehicle 1. As shown in FIG. The unmanned vehicle 1 is provided with sensors such as an ultrasonic sensor 3, a pickup coil 4, and an operation control sensor 5.

On the running road surface 6, a mark plate 7.7M for detecting the position of the unmanned vehicle I using the operation control sensor 5;
A magnetic proximity switch 8 for controlling intersection control, traffic light control, automatic door control, etc. for the unmanned vehicle 1, and a pit for collecting iron pieces and iron powder 9 that have fallen on the driving road surface 6. 10, are provided. Mark play) 7M is a mark plate for detecting the position of special hit 10. FIG. 3 shows the planar positional relationship between these mark plates 7.7M and pits 10. A permanent electromagnetic magnet 11 for activating the magnetic proximity switch 8 is further provided on the lower surface of the unmanned vehicle 1, and the permanent electromagnetic magnet 11 can be set in a demagnetized state or a constant magnetic state depending on the position of the unmanned vehicle. A control device 12 is mounted on the unmanned vehicle 1.

The structure of the permanent electromagnetic magnet 11 is shown in FIG. The structure of the permanent electromagnetic magnet 11 is such that a magnetic pole 21 is inserted into a fixed polarity permanent magnet 20, a permanent magnet 22 with reversible polarity is brought into contact with the magnetic pole 21, and a coil 23 is wound around the permanent magnet 22 with reversible polarity.
The whole is covered with a yoke 24. When the polarity of the fixed polarity permanent magnet 20 and the reversible polarity permanent magnet 22 are as shown in FIG. 4(a), the permanent electromagnetic magnet 11 is in a constant magnetic state. When the coil 23 is energized in this state, the polarity of the reversible permanent magnet 22 is reversed, and the permanent electromagnetic magnet 11 becomes demagnetized as shown in FIG. 4(b). When the coil 23 is energized again in this state, the polarity of the reversible permanent magnet 22 is reversed again, resulting in a constant magnetic force state as shown in FIG. 4(a). The coil 23 only needs to be energized during the state change while the polarity of the reversible permanent magnet 22 is reversed, which is an extremely short period of time.

When the unmanned vehicle 1 is used in a factory etc., the driving road surface 6
There is a possibility that iron pieces such as chips and iron powder 9 have fallen. When the above-mentioned unmanned vehicle 1 runs in such a place, the permanent electromagnetic magnet 11 has a constant magnetic force, so iron pieces and iron powder 9 falling on the running road surface 6
is attracted to the permanent electromagnetic magnet 11. Before these accumulate and the magnetic force of the permanent electromagnetic magnet 11 weakens, and the magnetic proximity switch 8 provided on the running road surface 6 cannot be activated, the unmanned vehicle 1 detects the position of the collection pit 10 using the operation control sensor 5. Detection mark play) Detects 7M and stops. At this time, the control device 12 controls the coil 23 of the permanent electromagnetic magnet 11.
A short-time energization command is issued. As a result, permanent electromagnetic magnet 1
1 is demagnetized, and the iron pieces and iron powder fall into the recovery pit 10 and are removed. Thereafter, the control device 12 issues an energization command again, and the permanent electromagnetic magnet 11 returns to a constant state of magnetic force. Recovery pit 10 and recovery pit detection mark play) 7
The number and installation position of M vary depending on the amount of iron pieces and iron powder 9 falling on the running road surface 6 and the length of the running road surface 6, and the permanent electromagnetic magnet 11 reliably operates the magnetic proximity switch 8. It must be determined that the retrieval pit 10 is encountered at such a frequency that the magnetic force is maintained.

When the unmanned vehicle 1 does not stop and drops the iron pieces and iron powder 9 attracted by the permanent electromagnetic magnet 11 into the collection pit 10, the length of the collection pit 10 is determined according to the speed of the unmanned vehicle 1. There is a need. Further, FIGS. 5 to 8 show an embodiment of a recovery pit 10' provided with a lid 30. Collection pit 10
' is a deep depression 31 in which iron pieces and iron powder are collected on the running road surface 6.
A shallow recess 32 for sliding the lid 30 is provided, and a rail 33 extends from above the shallow recess 32 to the deep recess 31. The lid 30 has wheels 34 for moving on rails 33 and a dog 3 that engages with a button 35 of the unmanned vehicle 1.
6, a spring 37 that biases the lid 30 to the closed position, and a spring 3
A stopper 38 for stopping the lid 30 before 7 becomes the shortest.
, and are provided. In addition, the dog 36 is connected to the lid 30 via a spring 39 that is twisted when the force exceeds a certain level.
It is pivoted to.

The recovery pit 10' operates as follows. Normal lid 30
is biased to the closed position by a spring 37, as shown in Figure 5.6. When the unmanned vehicle 1 comes above the recovery pit 10', the bushing 35 comes into contact with the dog 36. When the unmanned vehicle 1 moves further forward, the button 35 presses the dog 36, and the lid 30 slides in the direction of movement of the unmanned vehicle, bringing the lid 30 to the open position as shown in FIG. 7.8. . At this time, mark plate 7M indicates that unmanned vehicle 1
detects the position of the recovery pit 10', and the permanent electromagnetic magnet 11
The magnetic force is demagnetized and iron pieces, etc. are dropped into the collection pit 10'. Thereafter, the permanent electromagnetic magnet 11 is returned to a constant magnetic force.

As the unmanned vehicle 1 moves further forward, a large force is generated in the dog 36, the torsion spring 39 is twisted, the dog 36 and the button 35 are disengaged, and the restoring force of the spring 37 moves the lid 30 to the closed position. be returned.

In this way, a safe recovery pit with a simple structure is obtained in which the lid 30 automatically opens and closes as needed.

〔Effect of the invention〕

According to the present invention, it is possible to reliably operate a magnetic proximity switch buried in the road surface and used for various controls for an unmanned vehicle, thereby improving the reliability of the unmanned vehicle system. Furthermore, the magnetic force of the magnet provided on the underside of the unmanned vehicle to operate the switch is so strong that it can reliably operate the switch even if iron pieces and iron powder are attracted and accumulated. Even if the mark plate buried in the road surface for position detection is a permanent magnet, there is no risk of demagnetizing the magnetic force of the mark plate and disrupting the operation control of the unmanned vehicle. Furthermore, as the unmanned vehicle is running, iron pieces and iron powder that have fallen onto the road surface can be automatically collected, so there is no need to stop the unmanned vehicle system to clean the road surface. The operating rate of unmanned vehicle systems can be improved.

As described above, according to the structure of the present invention, the reliability and operation rate of the unmanned vehicle system are improved even though the size of the unmanned vehicle itself can be a normal size due to the small current consumption and simple control. A sensor device is obtained.

[Brief explanation of drawings]

Fig. 1 is a side view of an unmanned vehicle equipped with a sensor device according to the present invention, Fig. 2 is a front view thereof, Fig. 3 is a plan view thereof, and Figs. 4(a) and (b) are permanent electromagnetic magnets. 5 is a plan view of the lid closed position of the collection pit with a lid,
FIG. 6 is a side view thereof, FIG. 7 is a plan view showing the lid-opened position of the recovery pit with a lid, and FIG. 8 is a side view thereof. 1... Unmanned vehicle, 5... Position detection sensor, 7.7M... Mark plate, 8... Magnetic proximity switch, IO... Recovery pit, 11... Permanent electromagnetic magnet.

Claims (1)

[Claims] a permanent electromagnetic type magnet that is provided on the underside of the unmanned vehicle and can be switched between a magnetic state and a demagnetized state in order to operate a magnetic proximity switch buried in the road surface of the unmanned vehicle; A sensor device for an unmanned vehicle, comprising a control means for switching the magnetic force of the permanent electromagnetic magnet in order to remove iron pieces or the like that are attracted to the magnet while the unmanned vehicle is in operation.