JPH02283503A - Running device - Google Patents

Abstract

PURPOSE:To increase friction resistance between a wheel and a rail by providing a magnet on one of the wheel and the rail, and forming the other of magnetic material. CONSTITUTION:There are provided a plurality of iron cores 29, where a coil 28 is wound around the outer peripheral face of an inner wheel 2b fitted and fixed to a wheel shaft 25, to form an electromagnet 30 and an outer wheel 31 composed of hard magnetic material on the outer periphery of the iron cores 29. A current with specified strength is supplied to the coil 28 through a power supply part. A rail 15 is formed from magnetic material such as iron attracted by magnetic force generated at the magnet 30. It is thus possible to increase current supply to the magnet 30 at the time of acceleration or deceleration to increase attraction force of the magnet 30 resulting in increase in friction resistance of a driven wheel 9 to the rail 15 and prevention of slip.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to a traveling device that travels using frictional force generated between a rail and a wheel, and more particularly to a traveling device that prevents wheels from slipping during acceleration or deceleration.

(Prior Art) For example, in automatic assembly lines in factories, traveling devices are used that travel on rails laid along the lines. This traveling device has a vehicle body provided with a driving wheel and a driven wheel as wheels, and travels by driving the driving wheel by the frictional force generated between the driving wheel and the rail.

Wheels such as the driving wheels and driven wheels of such a traveling device are sometimes made of metal.

However, since metal wheels have a relatively low coefficient of friction, slippage occurs between them and the rails during acceleration and deceleration. This may cause the acceleration performance to deteriorate, making it impossible to reliably control the speed, or causing the stopping position to shift.

Therefore, in order to eliminate such problems, an elastic material having a large coefficient of friction, such as urethane rubber, is used for the wheels. However, wheels made of elastic materials have low abrasion resistance, so they are not only prone to early damage, but also are not suitable for use in clean environments such as clean rooms due to the generation of dust as a result of abrasion.

In addition, when a robot is installed on the vehicle body and a workpiece is transferred by this robot, when the robot's arm moves, the wheels elastically deform due to changes in its weight.
Sometimes the vehicle body tilts and the arm position shifts.

Furthermore, if the wheels themselves are elastically deformed, an error may occur between the actual travel command value and the stop position.

(Issue f+ to be solved by the invention) As described above, in the conventional traveling device, the wheels are made of an elastic material in order to increase the frictional resistance between the rail and the wheels. Therefore, the wheels tend to wear out easily, leading to early damage, generation of dust due to wear, and deterioration of positioning accuracy due to elastic deformation.

This invention was made based on the above-mentioned circumstances, and its purpose is that even if the wheels and rails are made of a rigid material such as a metal with excellent wear resistance, the wheels and rails An object of the present invention is to provide a traveling device that can sufficiently increase the frictional resistance between the rail and the rail.

[Structure of the invention] (Means and effects for solving the 5 problems) In order to solve the above problems, the present invention provides a vehicle body, a drive source provided on the vehicle body, and a drive source rotatably provided on the vehicle body. The wheel includes a wheel driven by the drive source and a rail on which the wheel rolls, one of the wheel and the rail is provided with a magnet, and the other is magnetically attracted to the magnet. Formed with materials.

With this configuration, the magnetic attraction force generated between the wheels and the rails acts as a frictional resistance between the rails and the wheels, making it difficult for slippage to occur.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. The traveling device shown in FIGS. 3 and 4 includes a vehicle body 1. The traveling device shown in FIGS. A robot 2 is provided on the upper surface of this vehicle body 1, and a hand 4 is provided at the tip of an arm 3 of this robot 2.

Further, a mounting plate 5 is fixed to the lower end surface of the vehicle body 1 via a connecting member 6. This mounting plate 5 has first and second brackets 7 at one end and the other end in the longitudinal direction of the vehicle body 1, respectively.
．． 8, the first bracket 7 is rotatably provided with a driving wheel 9, and the second bracket 8 is rotatably provided with a driven wheel 11.

In other words, the driving wheels 9 and the driven wheels 11 are arranged in a row at the center of the lower surface of the vehicle body 1 in the width direction.

Furthermore, a third bracket 1 is provided in the middle of the mounting plate 5.
2, and this third bracket 12 holds a DC motor 13 as a drive source. The rotation of the DC motor 13 is transmitted to the drive wheels 9 via a gear train 14.

The drive wheel 9 and the driven wheel 11 are mounted on a rail 15 so as to be freely rotatable. This shield 15 is placed on a base 16. Dye stands 17 are erected at predetermined intervals on both sides of the base 16, and an upper guide 18' is provided at the upper end of the stand 17 in parallel with the rail 15. A total of four left and right pairs of upper guide rollers 19 provided on the mounting plate 5 are in rolling contact with the inner surfaces of these upper guides 18. Further, lower guide rollers 21 are provided at the lower ends of the first bracket 7 and the second bracket 8 so as to roll into contact with both side surfaces of the rail 15. In other words, the upper guide roller 19 and the lower guide roller 21 prevent the vehicle body l from falling over in the width direction.

Further, a trolley duct 22 is provided on the frame 17 on one side of the base 16. A power supply IM 23 provided on the vehicle body 1 is in sliding contact with the trolley duct 22, so that power is supplied to the DC motor 13.

Note that 24 in the figure is an optical modem for exchanging signals between the vehicle body 1 and a $+ control section (not shown).

At least the driving wheel 9 of the driving wheel 9 and the driven wheel 11 is constructed as shown in FIG. In other words, 2 in the same figure
5 is an axle. This axle 25 has an inner ring 26 and a key 27.
are integrally fitted. A large number of iron cores 29 around which coils 28 are wound are provided radially on the outer peripheral surface of the inner ring 26, and an outer ring 31 is fitted onto the outer periphery formed by the tip surfaces of these iron cores 29. In other words, the coil 28 and the iron core 2
9 forms the main magnet 30. Above outer ring 3
1 is made of a hard magnetic material such as steel. A current of a predetermined strength is supplied to the coil 28 from a control section (not shown) via the power supply section 23. Thereby, the strength of the magnetic attraction force generated by the electromagnet 30 can be controlled.

Further, the rail 15 is made of a magnetic material such as steel that is attracted by the magnetic attraction force generated by the electromagnet 30.

In the traveling device configured in this manner, the current supplied to the electromagnet 30 increases in response to a signal from the control section during acceleration or deceleration. Then, since the magnetic attraction force generated in the electromagnet 30 becomes stronger, the frictional resistance between the drive wheel 9 on which the electromagnet 30 is provided and the rail 15 also increases.

Therefore, during acceleration or deceleration, the drive wheel 9 and the rail 15
Because slips are less likely to occur between the two, it is possible not only to set high acceleration and deceleration, but also to stop at a predetermined position with high precision.

Also, when driving at a constant speed other than when accelerating or decelerating, the electromagnet 30
The current to is reduced. As a result, the frictional resistance between the drive wheel 9 and the rail 15 is reduced, and the De motor 13
Constant-speed driving is performed with less load on the vehicle.

By the way, the total frictional force F between the drive wheels 9 and the rails 15 can be determined as follows. In other words, the load of the entire traveling device is W1, the load applied to the drive wheels 9 is W/2, the friction coefficient between the drive wheels 9 and the rail 15 is μ, and the magnetic attraction force generated by the electromagnet 30 is F- (where F' is the current , coil 28
is proportional to the magnetic permeability of the iron core 29), then F
-μ(W/2+F″)...Equation (1) is obtained.In other words, by providing the electromagnet 30, the frictional force is reduced to μ・F
It will increase by .

The value of F is determined by the current flowing through the coil 28, the number of windings, and the iron core 29.
Since it can be changed depending on the material of the material, it can be controlled easily and reliably.

5 and 6 show another embodiment of the invention, in which an electromagnet 40 is provided on the rail 15. That is, the rail 15 is formed in a hollow shape from a rigid material such as steel, and an iron core 42 around which a coil 41 forming an electromagnet 40 is wound is inserted into the hollow part. Further, the drive wheel 9 is made of a magnetic material that is attracted by the magnetic force generated by the electromagnet 40.

FIGS. 7 and 8 show further embodiments of the invention,
In this embodiment, a permanent magnet 50 is provided between the inner ring 26 and the outer ring 31 of the drive wheel 9 instead of the electromagnet 30. Even in such a structure, the magnetic force of the permanent magnet 50 causes the drive wheel 9 and the rail to be connected. 15 can be increased.

In each of the above embodiments, the electromagnet or permanent magnet is provided on the drive wheel, but the electromagnet or permanent magnet may also be provided on the driven wheel. It goes without saying that permanent magnets may be provided on the rail, and furthermore, the wheel or the one on which the magnet is provided may be made of a material other than a magnetic material that has a rigidity that is permeable to magnetic force.
For example, it may be made of ceramic or the like.

[Effects of the Invention] As described above, in this invention, a magnet is provided on either one of the wheel or the rail, and the other is made of a magnetic material that is magnetically attracted to the magnet. Frictional resistance due to magnetic force can be generated between the rail and the rail. Therefore, it is possible to eliminate the occurrence of slip between the wheels and the rails during acceleration and deceleration, so it is possible to improve acceleration and deceleration performance, and moreover, it is possible to accurately stop at a predetermined stopping position. . Furthermore, since the wheels and rails can be made of a material with low frictional resistance and rigidity, there is an advantage that dust generation due to wear can be prevented.

[Brief explanation of drawings]

Figures 1 to 4 show an embodiment of the present invention, with Figure 1 being a front view of the wheels and rails, Figure 2 being a side view, and Figure 3 being a side view of the wheels and rails.
4 is a front view of the traveling device, FIG. 4 is a side view, FIG. 5 is a front view of wheels and rails showing another embodiment of the invention, FIG. 6 is a side view, and FIG. A front view of a wheel and a rail showing still another embodiment of the invention, and FIG. 8 is a side view as well. 1... Vehicle body, 9... Drive wheel, 11... Driven wheel,
13...DC motor (drive source), 30.40...Electromagnet, 50...Permanent magnet.

Claims (1)

[Claims] A vehicle body, a drive source provided on the vehicle body, a wheel rotatably provided on the vehicle body and driven by the drive source, and a rail on which the wheel rolls; A traveling device characterized in that one is provided with a magnet, and the other is formed of a magnetic material that is magnetically attracted to the magnet.