JPS6338950B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a rolling motor that rotates at a low speed but can generate a large torque.

[Technology background]

Conventional motors are required to rotate at high speed because of their wide range of uses, and also from the viewpoint of electromagnetic conversion efficiency. In particular, in order to generate large torque while being lightweight, it has been thought that a motor that rotates at high speed and that uses a reduction mechanism to increase its power is good.

However, as electric machines are used in everyday things and more and more work is done next to the user, the presence of high-speed rotating motors nearby becomes dangerous for the user. Not recommended for safety. Therefore, there has been a demand for lightweight motors that are less dangerous, can generate large torque at low speeds, have simple speed reduction mechanisms, and are lightweight.

A simple example is an industrial robot, for example, if a 1m long arm turns at a speed of 1m/s, its rotational speed is 0.318 times per second, or 38 times per minute, which is a low speed. , a large torque of 1 kg-m is required to lift an object of 1 kg.

[Conventional technology and problems]

Most conventional motors operate at speeds of more than 1,500 revolutions per minute, and to generate the same torque of 1 kg-m at this speed, a motor larger than 2 horsepower is required. Therefore, conventionally, high-speed, low-torque motors were converted to low-speed, high-torque motors using reduction gears.

However, in order to reduce the speed from 1500 rotations to about 10 rotations, a multi-stage reduction gear mechanism is required, which increases loss, impairs precise movement due to backlash, and increases the weight of the reduction gear mechanism itself. However, there was a problem in that this hindered overall weight reduction.

On the other hand, in order to create a reduction gear mechanism with less loss and breakage, the gear must have high machining accuracy, especially gear cutting accuracy, resulting in high manufacturing costs.

[Purpose of the invention]

An object of the present invention is to provide a rolling motor that is essentially low-speed and high-torque, paying attention to the fact that such drawbacks can be solved by reducing the number of stages in the reduction gear mechanism.

[Structure of the invention]

In order to achieve this object, the rolling motor of the present invention includes a stator having a plurality of excitation magnetic poles arranged on a circumference, and a stator that contacts the inner surface of the circumference formed by the excitation magnetic poles, and the excitation magnetic poles are sequentially arranged. The rolling magnetic pole has a cylindrical rolling magnetic pole that rolls as it is excited, and a driven wheel that is rotatably supported concentrically with the inner center of a circumference formed by the exciting magnetic pole, A rolling motor in which a magnetic pole has an external ring formed concentrically with the rolling magnetic pole, and an internal ring formed concentrically with the driven wheel and an external ring are disposed on the driven wheel so as to engage with each other, The excitation magnetic pole has an extreme end forming a magnetic path loop parallel to the central axis of the circumference of the excitation magnetic pole, and a pair of circumferential rings are formed on both ends of the rolling magnetic pole to form a rotary arm side. The rotary arm is engaged with a pair of internal rings that are attached to the rotary arm, and the rotary arm is pivotally supported on both sides of the fixed arm concentrically with the center of the circumference.

[Embodiments of the invention]

Before describing one embodiment of the present invention in detail, an outline of its operation will be explained with reference to FIGS. 1 to 4.

FIG. 1 is a sectional view showing the basic configuration of a rolling motor 1 used in the present invention, and FIG. 2 is a perspective view showing the main parts of the rolling motor shown in FIG. 1 separated.

In FIGS. 1 and 2, 11 is a stator;
2a, 12b, 12c... are excitation magnetic poles, 1
3a, 13b, 13c... are excitation coils for corresponding excitation magnetic poles, 14 is a rolling magnetic pole, 15 is a rolling gear that is concentric with and integral with the rolling magnetic pole 14, and 16 is a driven gear that rotates concentrically with the stator 11. The gear 17 is a driven wheel concentric with and integral with the driven gear, and 18 is a guide sleeve fixed concentrically to the stator 11, and the driven wheel 17 can freely rotate inside the guide sleeve 18. 19 is a rotating shaft that transmits the rotation of the driven wheel 17 to the outside, and 20 is a cover that rotatably supports the rolling magnetic pole 14.

The rolling magnetic pole is a magnetic material, and its diameter 2R ₂ is set smaller than the inner diameter 2R ₁ of the exciting magnetic pole group 12a, 12b, . . . . Further, the rolling gear 15 meshes with the driven gear 16, and the two are in an internal gear relationship.

In this structure, the principle of rotation will first be qualitatively explained using FIG.

In FIG. 3, O is the center of the stator 11 and the excitation magnetic pole groups 12a, 12b, etc., and O' is the center of the rolling magnetic pole 1.
It is the center of 4. Note that excitation coils for each excitation magnetic pole are omitted.

When the excitation magnetic pole 12a is now excited, the rolling magnetic pole 14 of the magnetic material is attracted and the excitation magnetic pole 12 is at point A.
Touches a. The center of the rolling magnetic pole 14 at that time
O' is at the position of Oa, and O, Oa, and A are on a straight line.

Next, when the excitation of the next excitation magnetic pole 12b is increased from zero while decreasing the magnetic pole of the excitation magnetic pole 12a,
The rolling magnetic pole 14 rotates by the attractive force of the exciting magnetic pole 12b, and finally comes into contact with the exciting magnetic pole 12b at point B. At this time, the center O' of the rolling magnetic pole 14 is Ob
, and O, Ob, and B are on a straight line.
In this state, only the exciting magnetic pole 12b is excited.

Next, when the excitation of the next excitation magnetic pole 12c is increased from zero while decreasing the excitation of the excitation magnetic pole 12b, the rolling magnetic pole 14 is rotated by the attractive force of the excitation magnetic pole 12c, and finally the excitation magnetic pole The excitation of the magnetic pole 12b becomes zero and contacts the exciting magnetic pole 12c at point C. At this time, O, Oc, and C are also on a straight line.

Thereafter, when the next adjacent excitation magnetic poles are sequentially excited in the same manner, the rolling magnetic poles 14 become the excitation magnetic pole group 12a,
It rotates, that is, rolls, while contacting the inner periphery of the circle formed by 12b, . . . .

And the center O' of the rolling magnetic pole 14 is Oa, Ob, Oc...
It rotates counterclockwise on the circumference of radius OO′, but
If we pay attention to the rolling magnetic pole 14 itself, it rotates slowly clockwise about the center O'.

Next, the rotation of the rolling magnetic pole 14 will be explained quantitatively with reference to FIG. The meaning of each symbol is as follows.

R ₁ ; Inner radius of excitation magnetic pole group 12a, 12b... (center is O) R ₂ ; Outer radius of rolling magnetic pole 14 (center is O') R ₃ ; Pitch of rolling gear 15 concentric with rolling magnetic pole 14 Radius of the circle PC ₃ R ₄ ; radius of the pitch circle PC ₄ of the driven gear 16 concentric with the excitation magnetic pole group Now, when excitation is switched from the state where the excitation magnetic pole 12a attracts the rolling magnetic pole 14 to the excitation magnetic pole 12b To explain, the attractive force of the magnetic pole 12b
Since Fb acts almost in the radial direction, the rolling magnetic pole 14
A moment Mb expressed by the following formula with the instantaneous center at point A acts on .

Mb＝Fb・l……(1) However, l is the distance from point A to attraction force Fb.

The rolling gear 15 rotates together with the rolling magnetic pole 14, but since the rolling gear 15 meshes with the driven gear 16, the moment acting on the rolling magnetic pole 14 is reduced.
The same moment is generated in the driven gear 16 by Mb.

Assuming that the intersection point of the pitch circle PC ₄ of the driven gear 16 and the straight line OO'A is A ₁ , a downward force F ₁ acts on the driven gear 16 at A ₁ in the direction shown, that is, perpendicular to OA ₁ . If the distance of AA ₁ is δ, the moment acting on the driven gear 16 = F ₁・δ...
…(2) Since (1) = (2), Fb・l=F ₁・δ From this, F ₁ = Fb・l/δ……(3) In other words, a starting torque of F ₁ is generated in the driven gear 16. I will do it.

If δ is made small, F ₁ becomes extremely large, so a large force can be generated in the driven gear. This moment causes the rolling magnetic pole 14 to move to the third
As explained in the figure, the driven gear 16 slowly rotates clockwise while rolling on the inner surface of the excitation magnetic pole group and meshes with the rolling gear 15.
It rotates slowly clockwise.

Note that as the rolling magnetic pole 14 rolls, its center instantaneously shifts from point A and the leverage ratio decreases, but as the rolling magnetic pole 14 rolls, the gap between it and the exciting magnetic pole 12b decreases, and as a result, the attractive force increases, and as a result, the overall The moment hardly changes due to rolling.

Also, in Figure 4, there is a large gap between each excitation magnetic pole to make the explanation easier to understand, but in reality, the gap between each excitation magnetic pole is small, similar to the excitation magnetic pole of a conventional motor, and furthermore, the gap between each excitation magnetic pole is small. The excitation method is similar to the excitation method of conventional motors, in which a plurality of adjacent excitation magnetic poles are sequentially excited, so that a constant moment always acts on the rolling magnetic poles, and rolling occurs smoothly.

When the excitation goes around the circumference of the rolling magnetic pole 14 in this way, the point on the circumference that was at point A moves to _A2 .
If the angle AOA ₂ is θ, the rolling magnetic pole 14 will roll without slipping, and the following equation will hold true.

2πR ₁ = (2π + θ) R ₂ From this, θ = 2π (R ₁ + R ₂ ) / R ₂ = 2πδ / R ₂ ... (4) Similarly, the pitch circle PC ₄ of the driven gear 16 that is at point A ₁ moves to _A3 . If the angle AOA ₃ is φ, then
Since the driven gear 14 also rotates without slipping,
The following formula holds.

2πR ₃ θ=2πR ₄ φ From this, φ=R ₃ /R ₄ θ=2πR ₃・δ/R ₂・R ₄ …(5) If one round of excitation is one revolution of the input, the output φ is R ₃・δ/R ₂ R ₄ rotations...(6).

From equations (3), (5), and (6), if δ is made smaller, that is,
By bringing R ₁ and R ₂ close together, the reduction ratio can be increased and the starting torque can be increased, so a motor with the required low speed and large torque can be obtained all at once.

For example, in the case of the above-mentioned motor which generates a torque of 1 kg-m, if the excitation of the excitation magnetic pole is repeated once at 5 mS, the reduction ratio will be 315, which is 38 times per minute. now,
If we set R ₂ ≒ R ₃ ≒ R ₄ = R to find the approximate value, then
From equation (6), R ₃ /R ₂ R ₄ δ=δ/R=1/315.

On the other hand, since l and R are comparable, Fb is approximately as follows.

Fb≒1Kg-m×δ/R ₂ If R=50mm, Fb≒1Kg-m×(δ/R)1/R = 1Kg-m×1/315×1/0.05=0.063Kg In other words, Fb is as small as 63g Therefore, since the excitation magnetic pole is large enough to generate sufficient power even with a small magnet, the motor is much smaller than the weight of a conventional 2 horsepower motor.

Furthermore, since the speed reduction mechanism can be a single-stage internal gear type, it is much smaller and lighter than conventional speed reduction mechanisms using multiple stages of gears, and gear cutting accuracy is not required to be as high as in the past.

Furthermore, since the motor structure is simple and power is only supplied to the stator, manufacturing is easy and economical.

Note that a friction wheel may be used in addition to the gear mechanism as a means for transmitting the moment of the rolling magnetic pole 14 to the driven wheel 17.

5 and 6 show an embodiment of the present invention.

This is an example of a device built into the hinge of an industrial robot arm. By arranging the rolling gear and driven gear on both sides of the rolling magnetic pole, the stability of rotational motion is improved, and the excitation coil is Therefore, since the magnetic path of the electromagnet formed in the excitation magnetic pole is closed when viewed from the excitation coil, leakage magnetic flux can be significantly reduced.

The rotation operation is exactly the same as the operation schematic explanatory diagrams shown in FIGS. 1 to 4, and the configurations are also opposite, so the corresponding configuration and operation will be briefly explained.

In FIGS. 5 and 6, 11 is a stator, 12
a, 12b... are exciting magnetic poles, 13a, 13b... are exciting coils, 14 is a rolling magnetic pole, 15L and 15R are left and right rolling gears that are concentric and integral with the rolling magnetic pole 14, and 16L and 16R are fixed Driven gears 17L and 17 that rotate concentrically with child 11
R is a left and right driven wheel that is concentric with the left and right driven gears 16L and 16R, respectively, and is integral with the left and right driven wheels, 18L and 18R are guide sleeves that are fixed to the fixed arm 21 in a concentric relationship with the stator 11, and are connected to the left and right driven wheels 17L and 18R, respectively. 1
7R can freely rotate inside the guide sleeves 18L and 18R. In addition, left and right driven wheels 17L and 1
7R is integrally attached to the rotating arm 22.

With this configuration, when the exciting magnetic poles 12a, 12b... are sequentially excited by the exciting coils 13a, 13b...
The rolling magnetic pole 14 rotates slowly while rolling on the circumferential inner surface formed by the excitation magnetic pole group. The rotation of the rolling magnetic pole 14 is caused by the left and right driven gears 16 via the left and right rolling gears 15L and 15R.
It is transmitted to L and 16R, and rotates the left and right driven wheels 17L and 17R, which rotate together with the wheels. As a result, the rotating arm 22 will rotate.

According to the configuration of the present invention, since torque is transmitted and taken out in a balanced manner on both sides, it is easy to support the combination of the rolling magnetic pole and the outer ring, that is, the rolling magnetic pole, and the rolling magnetic pole 14 and the rolling gear Since the torsion due to the axial offset between 15L and 15R is canceled, no twisting occurs due to reaction to the generated torque.

A bearing structure connecting fixed arm 21 and rotating arm 22, that is, driven wheel 17 and guide sleeve 1
8 are on both sides, and can be supported on both sides concentrically and coaxially with the center of the excitation magnetic pole, so if the driven wheel and guide sleeve are supported from both sides as bearings for the joint that connects the fixed arm and the rotating arm, Since the torque is supported in a balanced manner from both sides, only a support compatible with the torque is required.

Moreover, since it can be constructed inside the joint, there is no need for parts such as a motor to protrude outside. Moreover, since the rolling magnetic pole is not an elastic body, there is little twisting and the holding rigidity is high.

[Effects of the Invention] According to the present invention, a small, lightweight, simple transmission mechanism, low cost, essentially low speed rotation and large torque,
Moreover, a balanced type motor can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a schematic explanatory diagram of the present invention, FIG. 2 is a perspective view showing the main parts separated, and FIGS. 3 and 4 are explanatory diagrams of the rotation principle of the rolling motor of the present invention. , FIG. 5 is a perspective view of one embodiment of the present invention, and FIG. 6 is a sectional view thereof. In the figure, 11 is a stator, 12a, 12b... are exciting magnetic poles, 13a, 13b... are exciting coils, 14 is a rolling magnetic pole, 15, 15L, 15R are rolling gears, 1
6, 16L, 16R are driven gears, 17, 17L,
17R is a driven wheel, 18, 18L, and 18R are guide sleeves, 19 is a rotating shaft, 20 is a cover, 21 is a fixed arm, and 22 is a rotating arm.

Claims (1)

[Scope of Claims] 1. A stator 11 having a plurality of excitation magnetic poles 12 arranged on a circumference, and a stator 11 having a plurality of excitation magnetic poles 12 arranged on a circumference, and a stator 11 that contacts an inner surface of a circumference formed by the excitation magnetic poles, and the excitation magnetic poles 12 are sequentially excited. A cylindrical rolling magnetic pole 14 that rolls along with the
and a driven wheel 17 rotatably supported concentrically with the inner center of the circumference formed by the excitation magnetic pole, and the rolling magnetic pole 14 has an outer ring 15 concentrically with the rolling magnetic pole 14. In a rolling motor in which an inner ring 16 formed concentrically with the driven wheel 17 and an outer ring 15 are disposed so as to engage with each other, the circle of the excitation magnetic pole 12 A pair of circumferential rings 15 are provided at both ends of the rolling magnetic pole 14 to form the extreme ends of the excitation magnetic pole forming a magnetic path loop parallel to the central axis of the circumference.
L and 15R are formed to engage with a pair of internal rings 16L and 16R formed on the rotating arm 22 side, and the rotating arm 22 is attached to the fixed arm 21 on both sides concentrically with the center of the circumference. A rolling motor characterized by supporting. 2. The rolling motor according to claim 1, wherein the outer ring is an external gear and the inner ring is an internal gear. 3. The rolling motor according to claim 1, wherein the outer ring is an external friction wheel, and the inner ring is an internal friction wheel.