JP2002264092A - Wheel for micro machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel for a micro machine having excellent turning performance. SOLUTION: Both end edge parts of a rolling surface in the cross section of the wheel passing an axle are formed into around shape or a chamfered shape, or the rolling surface is formed into a circular arc shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel for a micromachine, for example, a small traveling robot having a volume of 3 mm.
^{The present invention} relates to a traveling wheel composed of ^three or less.

[0002]

2. Description of the Related Art As a micromachine, for example, various small-sized traveling robots for inspecting a group of thin tubes, such as steam generating tubes of a power generation facility, for external damage have been proposed. In such a small traveling robot, wheels such as a driving wheel and a driven wheel driven by a driving device travel smoothly on a traveling surface (iron plate) that bundles the steam generating tubes without stopping halfway. Therefore, it is required to have a reliability that the pipe to be inspected can be reliably reached.

[0005] As this kind of small-sized traveling robot, FIGS. 5 to 7, the 7th Design Engineering and System Division Conference Lecture No. 5 published by the Japan Opportunity Society in 1997, No. 5
The small traveling robot described on pages 15 to 516 is presented. FIG. 5 is an exploded perspective view showing the configuration of the small traveling robot in a disassembled state, FIG. 6 is a bird's-eye view showing the traveling state of the small traveling robot, and FIG. 7 is the shape and shape of the driving wheels or driven wheels for the small traveling robot. It is an enlarged view showing a grounding state.

In FIG. 5, reference numeral 1 denotes a small traveling robot (hereinafter, also referred to as a robot) and 2 denotes a driving device. In this example, a micro electromagnetic motor is used.
Reference numeral 3 denotes a speed reduction / running device connected to the drive device 2, which is a speed reduction mechanism 4 using a planetary gear train, a drive wheel 5 mounted on a front lower portion of the speed reduction / running device, and mounted on a rear lower portion. Horizontal driven wheel 6, vertical driven wheel 7 attached to the upper front side, side plate 8, middle plate 9,
It is composed of an axle 10 and the like.

The above-mentioned drive wheels 5, horizontal driven wheels 6, and vertical driven wheels 7 are all so-called magnet wheels made of a magnetic material. As shown in FIG. 6, the small traveling robot 1 equipped with the magnet wheels travels between the groups of thin tubes 15 so as to sew.
Surrounding the outer peripheral surface of the thin tube 15a to be worked with a plurality of other robots, and connected to each other in a surrounding state,
While raising and lowering the thin tube 15a in the connected state, the thin tube 15a is inspected for damage such as breakage or cracks. Reference numeral 11 in FIG. 5 denotes a flaw detection device equipped with a sensor for inspecting the thin tube 15a for flaws, for example, an eddy current flaw detection sensor 12, and 13 denotes a micro connector for connecting the small traveling robots 1 to each other.

Next, the operation will be described. Figure 5 and Figure 6
In the small traveling robot 1, the micromotor 2 as a driving source rotates with electric power supplied from the outside via the micro connector 13, and this rotational force is transmitted to the driving wheels 5 via the speed reduction mechanism 4. For example, the vehicle travels as shown by the arrow in FIG. In FIG. 7, since a magnetic attraction force is generated in the drive wheel 5 by the magnetic path 18 formed between the drive surface 5 and the running surface (iron plate 14), the drive wheel 5 rotates with a small slip with respect to the running surface (iron plate 14). And efficiently transmit the driving force.

In FIG. 6, the robot 1 is steered by changing the number of rotations and the direction of rotation of the left and right driving wheels 5, and turns left and right or makes a U-turn. The environment in which the robot 1 is used, in this example, the running surface (that is, corresponding to the ground) on the iron plate 14 that bundles the steam generating pipes of the power plant is formed smoothly, and there is no large protrusion, and free running is possible. It has become. Since the outer diameter of the thin tube 15 is 22 mm and the interval between the outer surfaces is 10 mm, the volume of the small traveling robot 1 to be used is formed to be 10 ³ mm ³ or less. The robot 1 arriving at the target thin tube 15a contacts the driving wheel 5 and the vertical driven wheel 7 with the outer peripheral surface of the thin tube 15a and moves up and down without dropping by magnetic attraction.

[0008]

A wheel for a micromachine such as the small traveling robot 1 described above (the driving wheel 5 of the above example).
And the driven wheel 6) are generally merely formed in a columnar shape, so that each time the running direction of the wheel is turned left and right, both end portions (left and right edges) of the cylindrical rolling surface are formed. ) Bites into the running surface (the surface of the iron plate 14 in the above example), causing a catching state. In particular, this harmful effect becomes remarkable at the edge of the rolling surface that is the center side of the turning. When such a trapping state occurs, the coefficient of friction increases, slippage deteriorates, the vehicle cannot turn smoothly. Otherwise, it may cause a failure. In addition, it may cause unnecessary scratches on the running surface, which may cause corrosion and cause accidents due to the corrosion.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wheel for a micromachine capable of solving the above-mentioned problems and performing smooth and stable running, in particular, smooth turning.

[0010]

According to a first aspect of the present invention, there is provided a wheel for a micromachine, wherein the cross section of the wheel passing through the axle is:
It is characterized in that both end portions of the rolling surface are R-shaped.

According to a second aspect of the present invention, there is provided a wheel for a micromachine, wherein a cross section of the wheel passing through the axle has a shape in which both end edges of a rolling surface are chamfered.

According to a third aspect of the invention, there is provided a wheel for a micromachine, wherein a rolling surface has an arc shape in a cross section passing through an axle of the wheel.

The invention according to claim 4 is the invention according to claims 1 to 3.
Wherein the wheel is a magnet wheel made of a magnetic material.

The invention according to claim 5 is the invention according to claims 1 to 4.
The wheel for a micromachine according to any one of the above, wherein the wheel has a substantially columnar shape having an axle as an axis.

The invention of claim 6 is the first to fifth aspects of the present invention.
The wheel for a micromachine according to any of the above, the wheel has a magnet portion formed of a magnetic material at the center in the axle direction in a cross section passing through the axle, and is formed of a soft magnetic material on both sides of the magnet portion. A yoke portion.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Embodiment 1
Both ends of a rolling surface of a wheel for a micromachine (hereinafter, also referred to as a wheel) have a shape with an R (hereinafter, referred to as an R shape) in a cross section of the wheel passing through an axle. Hereinafter, this will be described with reference to FIG. FIG. 1 is an enlarged sectional view showing a state in which wheels are in contact with a running surface (the surface of the iron plate 14 of the conventional example). Since the same reference numerals as those described with reference to FIGS. 5 to 7 have substantially the same contents,
The description is omitted.

In FIG. 1, reference numeral 19 denotes a wheel of the first embodiment. The wheel 19 is a so-called magnet wheel formed of a substantially cylindrical shape using a magnetic material such as a permanent magnet such as samarium cobalt or neodymium boron. This wheel 1
In the cross section passing through the axle (not shown), the both ends B, B of the rolling surface 9 are the edges where the left and right end surfaces (corresponding to the cylindrical end surfaces) of the wheel 19 intersect with the rolling surface. The part is R shape B,
B is processed. In the first embodiment, the width of the rolling surface (in the width direction of the wheel) is increased in order to increase the contact area with the running surface and efficiently utilize the magnetic attraction force on the running surface. I'm making it smaller.

As described above, by forming the R-shaped roundness on both end edges B and B sides of the rolling surface, it is possible to reduce
Biting of the edge of the wheel 19 with respect to the running surface can be eliminated, so that the vehicle can be turned smoothly. Further, no unnecessary scratches are caused on the running surface.

Embodiment 2 The second embodiment is different from the first embodiment in that the structure of the wheel in which both ends B and B of the rolling surface are rounded in an R shape is formed such that a magnetic structure is provided at the center in the axle direction in a cross section passing through the axle. The magnet portion made of a material has a sandwich-like structure in which yoke portions made of a soft magnetic material are arranged on both sides of the magnet portion.
This will be described with reference to FIG. FIG. 2 is an enlarged cross-sectional view showing a state where the wheels are in contact with a running surface (the surface of the iron plate 14 of the conventional example). Note that other configurations are the same as those of the first embodiment.
Is the same as

In FIG. 2, the wheel 1 according to the first embodiment is shown.
Reference numeral 9 denotes a magnet wheel which is entirely constituted by a magnet unit using a permanent magnet. In Embodiment 2, the magnet wheel is
In a cross section passing through the axle (not shown), a magnet portion 20 made of the same magnetic material as in the first embodiment is disposed at the center in the axle direction, and pure iron,
Yoke portions 21, 21 made of soft magnetic material such as structural carbon steel, cast steel, silicon steel plate, permalloy, and cementum
Are arranged to be integrally formed. Therefore, an R-shape is formed on these yoke portions 21 and 21 located on both ends of the wheel.

In the second embodiment, the yoke portions 21 and 21 are provided at both ends of the magnet portion 20 so that the magnetic path 18A of the first embodiment shown in FIG. A magnetic path 18B of the magnet portion 20 is formed between the yoke portions 21 and 21 and the running surface (iron plate 14) at the shortest distance. Therefore, the wheel 1 according to the first embodiment described above.
As compared with No. 9, the wheels (20, 21) of this form 2 are
The magnetic attraction force of the magnet section 20 can be efficiently used, and a large magnet attraction force can be applied to the running surface (iron plate 14).

In the first embodiment, for example,
Wheel 19 made of a magnetic material such as samarium cobalt
In this case, the magnetic material was brittle, and there was a possibility that the edges would be chipped during running. However, since the yoke portions 21 and 21 having high brittle fracture strength of the soft magnetic material were provided on both sides, the edge portions were damaged. It is possible to prevent the wheels from being damaged as in the above-described case.
Also, compared to the magnetic material of the magnet part 19, the yoke material part 21,
Forming an R shape on the soft magnetic material No. 21 also has an advantage that processing becomes easier.

Further, since the rolling edge of the wheel (20, 21) of the second embodiment is also provided with an R-shaped roundness, the same operation and effect as in the first embodiment, for example, the turning performance, can be obtained. Of course, but in addition to this, the wheels (20, 21) are combined with the large magnet attraction force obtained by providing the wheels with the yoke portions 21, 21. Can greatly stabilize the running performance.

Embodiment 3 FIG. In the third embodiment, a chamfered shape (hereinafter, also referred to as a chamfered shape) is used instead of forming the R shape at both end portions of the rolling surface of the wheel of the first embodiment. This will be described with reference to FIG. FIG. 3 shows the running surface of the wheel (the surface of the iron plate 14 of the conventional example).
FIG. 4 is an enlarged view showing a state in contact with. The other configuration is the same as that of the first embodiment.

In FIG. 3, the third embodiment is different from the first embodiment in that a wheel 2
The two end portions C, C have a chamfered shape. As described in the second embodiment, when the magnet portion 22 is made of a magnetic material such as samarium cobalt, the material is fragile, so that the magnet portion 22 of the third embodiment has a smaller shape than the process of forming the R shape. Processing into such a chamfered shape is relatively easy, and the manufacturing cost can be reduced.

Of course, the chamfered shape as described above can be formed, for example, on the yoke portions 21, 21 in the wheels (20, 21) having the configuration of the second embodiment (not shown). In this case, there is no processing problem as described in the third embodiment, but rather a wheel that is easy to process and has a high brittle fracture strength, so that the edges C, C are unlikely to be lost. be able to.

Further, according to the third embodiment, the turning performance similar to that of the first embodiment can be obtained with any of the above-described wheels. Further, by making the configuration of the wheel the same as that of the second embodiment, it is possible to obtain the same operation and effect as that of the second embodiment.

Embodiment 4 In the fourth embodiment, the rolling surface of the wheel is formed in an arc shape in a cross section of the wheel passing through the axle, instead of providing the R-shaped portions at both end portions of the wheel 19 in the first embodiment. This will be described with reference to FIG. FIG. 4 is an enlarged cross-sectional view showing a state where the wheels are in contact with a running surface (the surface of the iron plate 14 of the conventional example).
The other configuration is the same as that of the first embodiment.

In FIG. 4, the wheels 23 shown in the fourth embodiment are shown.
In the cross section passing through the axle, the rolling surface of the wheel is formed in an arc shape, and the entire shape of the wheel 23 is a Japanese drum shape. In addition, in this specification, such a Japanese drum shape is also used in a meaning including a substantially cylindrical shape. When the wheel 23 has a Japanese drum shape in this way, the rolling surface and the running surface of the wheel are in point contact with an arc-shaped curved surface and a flat surface (the running surface), or are in contact with the ground by line contact. Since the contact area is greatly reduced, it is possible to provide a wheel having a much smaller turn and a high turning performance as compared with the forms of the wheels of the first to third embodiments.

On the other hand, the running stability can be ensured by setting the magnetic attraction to the running surface of the wheels 23 relatively high. In this case, of course, in the second embodiment,
As shown in the wheel structure of FIG.
By adopting the structure provided with 1 and 21, the magnetic attraction force can be further increased in the same manner as in the second embodiment, so that running stability can be obtained.

In each of the above embodiments, the micromachine wheel of the present invention has been described as a wheel of a small traveling robot, but the present invention is not limited to this. The micromachine is not limited to a small traveling robot, and can be used as a wheel of any device. The wheels used in such a case need not necessarily be magnet wheels. In addition, the effect of the turning performance and the effect of preventing the running surface from being damaged by the shapes of the both end portions of the rolling surface in the first and third embodiments and the shape of the rolling surface in the fourth embodiment is that the wheels are not magnet wheels. It is also demonstrated on normal wheels.

[0032]

According to each of the first to sixth aspects of the present invention, during turning, there is no possibility that both end portions of the rolling surface of the wheel will scratch the running surface, so that the vehicle smoothly turns. Thus, a micromachine wheel having stable operability can be provided.

According to the third aspect of the present invention, since the contact area between the rolling surface and the running surface is greatly reduced, the turning performance and the operability are further improved as compared with the first and second aspects of the present invention. Can provide the micro machine wheels

According to the sixth aspect of the present invention, since the yoke portions of the soft magnetic material are provided on both sides, the brittle fracture strength is increased, and the wheel is prevented from being damaged due to the loss of the both edges of the rolling surface. can do. Further, the yoke portion allows the magnet attraction force of the magnet portion to be efficiently exhibited, and the traveling performance as a magnet wheel can be greatly improved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a wheel according to a first embodiment.

FIG. 2 is an enlarged sectional view of a wheel according to a second embodiment.

FIG. 3 is an enlarged sectional view of a wheel according to a third embodiment.

FIG. 4 is an enlarged sectional view of a wheel according to a fourth embodiment.

FIG. 5 is an external exploded perspective view showing the configuration of the small traveling robot in a disassembled state.

FIG. 6 is a bird's-eye view showing a traveling state of the small traveling robot.

FIG. 7 is an enlarged view showing a shape of a driving wheel or a driven wheel for a small traveling robot and a ground contact state.

[Explanation of symbols]

1 Small traveling robot, 2 driving devices, 5 driving wheels, 6 horizontal driven wheels, 7 vertical driven wheels, 18, 18A, 1
8B, 18C, 18D magnetic path, 19, 22, 23 wheels, 20 magnet part, 21 yoke part, A edge part, B
R shape (edge), C chamfered shape (edge).

Claims (6)

[Claims] 1. A wheel for a micromachine, characterized in that, in a cross section passing through an axle of a wheel, both end portions of a rolling surface are R-shaped. 2. A wheel for a micromachine, wherein a cross section of a wheel passing through an axle has a shape in which both end portions of a rolling surface are chamfered. 3. A wheel for a micromachine, wherein a rolling surface is formed in an arc shape in a cross section passing through an axle of the wheel. 4. The micromachine wheel according to claim 1, wherein the wheel is a magnet wheel made of a magnetic material. 5. The wheel for a micromachine according to claim 1, wherein the wheel has a substantially columnar shape with an axle as an axis. 6. The wheel has a magnet portion formed of a magnetic material at the center in the axle direction and a yoke portion formed of a soft magnetic material on both sides of the magnet portion in a cross section passing through the axle. The wheel for a micromachine according to any one of claims 1 to 5, characterized in that: