JPH0262427A - Torque transmitting device - Google Patents

Abstract

PURPOSE:To permit great torque transmission and smooth turning drive by rotating a drive magnet around the first axial line due to rotation of a prime motor so that a magnet adjacent to a slave gear gives the slave gear a rotational force to rotate a slave motor. CONSTITUTION:When a prime motor 12 is rotated toward an arrow mark R, a drive magnet 14 adjacent to a slave gear 24 is placed somewhat on a front side in a rotational direction to a gear 24. Attracting force F2 due to a magnet 14a is thus directed in a inclined direction to an axial line to produce rotational force F3. That is, the slave gear 24 is subjected to the force F3 to give a slave gear 22 turning drive. At this time when the slave gear 22 is given turning drive, the magnet 14a is displaced gradually to the inner periphery of the slave gear 24 along the inside wall 25a of a groove 25. Therefore, when the magnet 14 is spaced from the slave gear 22, the magnet 14a has not operation of rotational force but only operation of axial force to displace smoothly the magnet 14a to the inner periphery. Also, similarly when a magnet 14b comes near to the gear 24 as the gear 22 is rotated, the magnets 14a, 14b are exchanged smoothly not to cause any irregular rotation of the gear 22.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for transmitting rotational force between two shafts using magnetic force.

[Conventional technology]

2. Description of the Related Art Conventionally, as a device for transmitting the rotational force of a driving shaft to a driven shaft by magnetic force, there has been known a device disclosed in Japanese Patent Application Laid-Open No. 170964/1983. This conventional device has a rotating body fixed to a driving shaft and a rotating body fixed to a driven shaft,
These rotating bodies are arranged with their outer peripheral surfaces close to each other,
Further, magnets are provided at equal intervals on the outer peripheral surface of each rotating body.

Therefore, when the driving shaft side rotating body rotates, the driving shaft side magnet approaches and moves away from the driven shaft side magnet, thereby rotationally driving the driven shaft side rotating body.

[Problem to be solved by the invention]

In such a conventional device, only a small number of all magnets are close to each other, that is, only a small number of magnets contribute to the transmission of rotational force. Therefore, it is difficult to transmit a large rotational force between the driving shaft and the driven shaft, and if a large rotational force is to be transmitted, the problem arises that the magnet and the rotating body must be made larger. Further, as the rotating body rotates, the distance between the magnets transmitting the rotational force changes, so the attractive force between these magnets also changes. As a result, a problem arises in that the rotational force transmitted between the driving shaft and the driven shaft changes depending on the rotation angle of the rotating body, causing uneven rotation of the rotating body on the driven shaft side.

SUMMARY OF THE INVENTION The present invention has been made with the object of providing a rotational force transmission device that is capable of transmitting a large rotational force between a motive vehicle and a driven vehicle, and that can smoothly rotate and drive the driven vehicle.

[Means to solve the problem]

The rotational force transmission device according to the present invention is formed of a driving wheel that is rotatably supported around a first axis and has a driving plane perpendicular to the first axis, and a permanent magnet, and has a driving plane on the driving plane. driving magnets arranged at equal intervals around a first axis; and rotatably supported around a second axis parallel to the first axis, perpendicular to the second axis and in the driving plane. It is characterized by comprising a driven wheel having opposing driven planes, and driven teeth formed of a ferromagnetic material or a permanent magnet and provided on the driven plane at equal intervals around a second axis.

[For production]

The drive magnet rotates around the first axis due to the rotation of the prime mover, and one of the drive magnets that is close to the driven tooth applies a rotational force to the driven tooth, thereby rotationally driving the driven wheel.

〔Example〕

The present invention will be explained below with reference to illustrated embodiments.

FIGS. 1(a) and 1(b) show a first embodiment of the present invention. The driving shaft 11 is rotatably supported around a first axis and connected to a rotational drive source (not shown).

The driven shaft 21 is rotatably supported around a second axis that is slightly eccentric and extends parallel to the first axis. A disk-shaped motive wheel 12 is integrally fixed to the motive shaft 11 and has a first
It has a drive plane 13 perpendicular to the axis of. The disc-shaped driven wheel 22 is integrally fixed to the driven shaft 21 and has a driven plane 23 perpendicular to the second axis. That is, the centers of the prime mover 12 and the driven wheel 22 are eccentric from each other. Further, the driven plane 23 is located parallel to the drive plane 13 of the motive vehicle 12, and these planes 13 and 23 face each other at a predetermined interval.

In this embodiment, the prime mover 12 and the driven wheel 22 are made of ferromagnetic material. Drive magnets 14 made of permanent magnets and formed in a cylindrical shape are arranged on the drive plane 13 at equal intervals on a circumference centered on the first axis, and are attached to the drive plane 13 by adhesive or mechanical restraint. Fixed by other methods such as The tip surfaces of the driving magnets 14 are flat and face the driven plane 23 at a minute interval, and the heights of the tip surfaces of the driving magnets 14 are equal to each other. Driven plane 23
are finished as smooth as possible, and a small amount of magnetic fluid 15 is held between each drive magnet 14 and the driven plane 23, respectively. The magnetic fluid 15 is always attracted to the drive magnet 14 and rotates together with the drive magnet 14 . Driven vehicle 2
Grooves 25 are formed at equal intervals on the circumference centered on the second axis, and between these grooves 250, the driven teeth 2
4 is formed. Sixteen drive magnets 14 are thrown, and eighteen driven teeth 24 are formed.

As will be described in detail later, when the motive wheel 12 rotates, some of the drive magnets 14 apply a rotational force to the driven teeth 24, thereby rotationally driving the driven wheel 22.

Since the center of the driving wheel 12 and the center of the driven wheel 22 are eccentric from each other, as shown in FIGS. ) approaches the driven tooth 24, the remaining drive magnet 14b (located at the bottom in the figure) is located on the inner circumferential side of the driven tooth 24. As shown in FIG. 1(b), the groove 25 is connected to the driven wheel 22.
The inner wall surface 25a has an arc shape. This circular arc shape is formed when the drive magnet 14a that is close to the driven tooth 24 rotates and moves to the inner circumferential side of the driven tooth 24, and when the drive magnet 14a that is located on the inner circumferential side of the driven tooth 24
The shape is such that it follows the locus of movement of the driving magnets 14a and 14b when the magnet b rotates and approaches the driven tooth 24.

In this embodiment, the width T of the driven tooth 24 is equal to the diameter of the drive magnet 14, and the width G of the outer circumference of the groove 25 is larger than the width T of the driven tooth 24. However, the width T of the driven tooth 240 and the diameter of the drive magnet 14 are not necessarily equal, and the width T of the driven tooth 24 and the width G of the outer circumference of the groove 25 are not limited to specific sizes. - As can be understood from FIG. 1(a), the depth of the blade groove 25 in the axial direction is set to approximately half the plate thickness of the driven wheel 22 in this embodiment;
This depth is determined based on the size and strength of the drive magnet 14, or other conditions.

Note that this groove 25 may pass through the driven wheel 22 in the axial direction.

The direction of the magnetic poles of the driving magnet 14 is shown in FIG. 2(a).

As shown in (b) and (C), a line passing through both the N and S magnetic poles of one drive magnet 14 is
is determined to be orthogonal to the driven plane 23 of. Further, the directions of the N and S poles of the adjacent drive magnets 14 are opposite, that is, the drive magnet 14 adjacent to the drive magnet 14 whose N pole is located on the driven vehicle 22 side has its S pole located on the driven vehicle 22 side. It looks like this.

The number of driving magnets 14 is an even number, and in this embodiment, 1
The driving magnet 14 is provided with a driving wheel 12 and a driven wheel 22 made of a ferromagnetic material at both poles, so that a closed magnetic circuit is formed.

The magnetic fluid 15 is provided to more reliably transmit the rotational force of the drive magnet 14 made of a permanent magnet to the driven wheel 22. The amount of magnetic fluid 15 is such that the magnetic fluid attracted to one driving magnet 14 does not connect to the magnetic fluid attracted to the adjacent driving magnet, and when the driving wheel 12 and the driven wheel 22 rotate, the magnetic fluid is centrifuged. It is determined not to be released from the drive magnet 14 by force.

Next, the operation of this embodiment will be explained with reference to FIGS. 2(a), 2(b), and 2(c).

When the drive shaft 11 and the drive wheel 12 are rotated by the drive source, those of the drive magnets located on the inner circumferential side of the driven teeth 24 (represented by reference numerals in FIG. 1(b) and FIG. 2(a)) 14b) do not directly oppose the driven tooth 24, as shown in FIG. 2(a). therefore,
The driven wheel 22 receives only an attractive force F in the axial direction from the driving magnet 14b, and does not receive any force in the rotational direction. Note that the driven wheel 22 is firmly fixed to the driven shaft 21, and will not be displaced toward the motive wheel 12 by this attraction force F.

Among the drive magnets, those close to the driven teeth 24 (see Fig. 1)
b) and 14 in FIGS. 2(b) and (C).
a) is located in front of the driven tooth 24 when the prime mover 12 is not rotating, as shown in FIG. 2(b). Therefore, the driven tooth 24 receives an attractive force F in the axial direction due to the drive magnet 14a.

It receives only force in the direction of rotation, and does not receive force in the direction of rotation. However, the prime mover 1
2 is rotating along the arrow R, the drive magnet 14a close to the driven tooth 24 is located slightly forward of the driven tooth 24 in the rotational direction, as shown in FIG. 2(C). .

Therefore, the attractive force F2 by the drive magnet 14a is oriented obliquely to the axis, and as a result, a force F in the rotational direction is generated. That is, the driven tooth 24 is this rotating blade,
The driven wheel 22 is rotationally driven by the force F3 in the direction.

When the driven wheel 22 is rotationally driven, the driving magnet 14a close to the driven tooth 24 is gradually displaced toward the inner peripheral side of the driven tooth 24 along the inner wall surface 25H of the groove 25.

Therefore, when the drive magnet 14a is moving away from the driven tooth 22, no force in the rotational direction acts on the drive magnet 14a, and only a force in the axial direction acts on the drive magnet 14a. displacement is performed smoothly. Further, the drive magnet 14b located on the inner peripheral side of the driven tooth 24 is connected to the driven wheel 2.
The same is true when approaching the driven tooth 24 as the tooth 2 rotates. Therefore, the drive magnet 14 that contributes to the rotation of the driven wheel 22
The replacement of the driving magnet 14b that does not contribute to this rotation is smoothly performed, and as a result, the rotational force is stably transmitted between the prime mover 12 and the driven wheel 22.
There will be no uneven rotation. The number of rotations of the driven wheel 22, that is, the reduction ratio, is determined by the number of drive magnets 14 and the number of driven teeth 2.
It is determined by the ratio to the number 4.

As described above, according to this embodiment, about half of the drive magnets 14 are close to the driven teeth 24 and contribute to the transmission of rotational force, and the magnetic fluid 15 is held between the drive magnets 24 and the driven plane 23. be done. Therefore, many magnets contribute to the transmission of rotational force, and the magnetic force acting space between the driving magnet 24 and the driven plane 23 is filled with the magnetic fluid 15, and there is no working distance, and the driving magnet 24 and the driven plane Since there is no leakage of magnetic flux between the driving wheels 12 and 23, the transmission efficiency of the rotational force from the prime mover 12 to the driven wheel 22 is high, and it is possible to transmit large rotational force while decelerating it. In this embodiment, the motive wheel 12 is provided with 16 driving magnets 14 and the driven wheel 22 is provided with 18 driven teeth 24.
The rotational speed is reduced to 16/18, but by appropriately setting the number of drive magnets 14 and driven teeth 24, any reduction ratio can be obtained. Conversely, by making the number of drive magnets 14 greater than the number of driven teeth 24, the drive wheel 1
It is also possible to speed up the rotation of No. 2.

In this embodiment, since the inner peripheral side wall surface 25a of the groove 25 has a shape that follows the locus when the driving magnet 14 moves toward the inner peripheral side of the driven tooth 24, the rotational force of the prime mover 12 is smoothly applied. This is transmitted to the driven wheel 22, and the driven wheel 22 can perform steady rotation without unevenness. Furthermore, since this embodiment uses magnetic force to transmit the rotational force, there is no mechanical friction loss, so the transmission efficiency of the rotational force is high, and since there is no mechanical contact, vibrations and Less noise, dust, and wear. Furthermore, if a rotational force greater than a set value is applied, slippage occurs and the rotational force is no longer transmitted, so the device of this embodiment can be used as a torque limiter.

FIG. 3 shows a second embodiment of the invention.

To explain only the parts that are different from the first embodiment, this second embodiment
In the embodiment, a thin plate 31 made of a non-magnetic material is provided between the motive wheel 12 and the driven wheel 22, and the magnetic fluid 15 is held between the drive magnet 14 and the thin plate 31.

A minute gap 32 is formed between the thin plate 31 and the driven plane 23 of the driven wheel 22, and the groove 25 passes through the driven wheel 22 in the axial direction. The other configurations are the same as in the first embodiment.

In this embodiment, the driven wheel 22 is provided in a vacuum chamber, and the magnetic fluid 15 is provided only on the side of the prime mover 12 which is in the atmosphere, but if both the prime mover 12 and the driven wheel 22 are placed in the atmosphere In this case, the magnetic fluid 15 may be provided on both sides of the thin plate 31.

In this second embodiment, the driven wheel 22 is configured to be rotationally driven from outside the thin plate 31, so the driven wheel 22 can be placed in a room in a special environment that is isolated from the outside, such as a vacuum room. is particularly suitable for being driven in rotation by an externally arranged prime mover 12. Other functions of the second embodiment are similar to those of the first embodiment.

In addition, in the first and second embodiments, the direction of the magnetic poles of the drive magnet 14 is determined such that a line passing through the N and S poles is orthogonal to the driven plane 23, and the N and S poles of the adjacent drive magnets 14 are However, when the driven wheel 22 is made of a ferromagnetic material, the rotational force is transmitted regardless of the orientation of the drive magnet 14.

FIGS. 4(a) and 4(b) show a third embodiment of the present invention.

In this embodiment, the driven wheel 22 is formed of a permanent magnet, and its center side is magnetized to the north pole, and the outer circumference side is magnetized to the south pole. All driving magnets 14 are driven by driven wheels 22.
The magnetic poles are arranged in the north pole on the side and the south pole on the motive vehicle 12 side, that is, the direction of the magnetic poles is unified in one direction. Further, the groove 25 passes through the driven wheel 22 in the axial direction, similarly to the second embodiment. The other configurations are the same as in the first embodiment. Note that the center side of the driven wheel 22 may be magnetized to the S pole and the outer circumferential side thereof to the N pole, and the driving magnet 14 may be arranged so that the driven wheel 22 side is the S pole and the driving wheel 12 side is the N pole. .

The operation of the third embodiment is basically the same as that of the first and second embodiments, and the rotational force of the motive vehicle 12 is efficiently and smoothly transmitted. Furthermore, according to the third embodiment, since the driven wheel 22 is formed of a permanent magnet, the attractive force is strong and it is possible to transmit a larger rotational force than in the first and second embodiments.

FIG. 5 shows a fourth embodiment of the invention.

In the fourth embodiment, the driven wheel 22 is made of a permanent magnet, and the side of the driving wheel 12 is magnetized to the south pole, and the opposite side is magnetized to the north pole. All of the drive magnets 14 are arranged such that the driven wheel 22 side is the north pole and the motive wheel 12 side is the south pole, that is, the direction of the magnetic poles is unified in one direction. Further, the groove 25 passes through the driven wheel 22 in the axial direction, as in the third embodiment.

The other configurations are the same as in the first embodiment. Note that the driven wheel 22 is magnetized so that the drive wheel 12 side is N pole and the opposite side is magnetized S pole, and the drive magnet 14 is arranged so that the driven wheel 22 side is S pole and the drive wheel 12 side is N pole. Good too.

The operation of this fourth embodiment is basically the same as each of the above embodiments, and the rotational force of the motive vehicle 12 is efficiently and smoothly transmitted. Further, according to the fourth embodiment, since the driven wheel 22 is formed of a permanent magnet, the attractive force is strong and the first and second
It becomes possible to transmit a larger rotational force than in the embodiment.

In the third and fourth embodiments, the directions of the magnetic poles of the drive magnet 14 and the driven wheel 22 are determined so that the different poles are close to each other, and the rotational force is transmitted by the attractive force. Alternatively, the same polarities may be brought close to each other and the rotational force may be transmitted by repulsion.

In each of the first to fourth embodiments, the motive wheel 12 is made of a ferromagnetic material, but rotational force can still be transmitted even if it is made of a non-magnetic material, and the material may be used. do not have. On the other hand, the driven wheel 22 does not need to be entirely made of a ferromagnetic material or a permanent magnet, and only the portion of the driven teeth 24 and the portion on which the drive magnet 14 acts may be made of a ferromagnetic material or a permanent magnet. Other parts may be made of non-magnetic material.

Furthermore, although the magnetic fluid 15 is provided in each embodiment, rotational force can still be transmitted even if this is omitted. Further, the driving magnets 14 do not have to be cylindrical, but may be prismatic, and the number thereof does not have to be an even number. Further, the shape of the wall surface 25a on the inner peripheral side of the groove 25 does not have to be an arc, and does not necessarily have to follow the movement locus of the drive magnet 14.

〔effect〕

As described above, according to the present invention, it is possible to obtain a rotational force transmission device that is capable of transmitting a large rotational force between a motive vehicle and a driven vehicle, and is capable of smoothly rotationally driving the driven vehicle.

[Brief explanation of the drawing]

Fig. 1(a) is a sectional view showing the first embodiment, Fig. 1(b)
is a sectional view taken along line B-B in Fig. 1(a), Fig. 2(a) is a sectional view showing a state in which the drive magnet is located on the inner peripheral side of the driven tooth, and Fig. 2(b) is a A cross-sectional view showing a state in which the drive magnet is close to the driven tooth and the prime mover is not rotating. FIG. 2 (C) is a cross-sectional view showing a state in which the drive magnet is close to the driven tooth and the prime mover is rotating. , Fig. 3 is a sectional view showing the second embodiment, Fig. 4(a) is a sectional view showing the third embodiment, Fig. 4(b)
is a sectional view taken along line BB in FIG. 4(a), and FIG. 5 is a sectional view showing the fourth embodiment. 12...Motive vehicle, 13...Driving plane, 14
... Drive magnet, 22... Driven wheel, 23... Driven plane, 24... Driven tooth. (O No. Figure 3 (b) Funeral diagram Figure 4 Figure 4)

Claims (2)

[Claims] 1. A motive wheel is rotatably supported around a first axis and has a drive plane perpendicular to the first axis, and a permanent magnet is arranged on the drive plane at equal intervals around the first axis. a driven wheel rotatably supported around a second axis parallel to the first axis, and having a driven plane perpendicular to the second axis and opposite to the drive plane; A rotational force transmission device comprising driven teeth formed of a ferromagnetic material or a permanent magnet and provided on the driven plane at equal intervals around the second axis. 2. The rotational force transmission device according to claim 1, wherein a magnetic fluid is held between the driving magnet and the driven plane.