JPS6223361A - Motor actuator - Google Patents

Abstract

PURPOSE:To facilitate production and enhance efficiency, by providing the center of a rolling and rotating rotor with a female screw, and by forming an output shaft for output of a male screw which is inserted into and is engaged with the female screw. CONSTITUTION:A rotor chamber 2 is formed cylindrically inside a stator 1, and in the chamber 2, a disc-formed rotor 10 is fitted. The stator 1 is organized so that respective coils 50-53 may be wound up to surround respective yokes 60-63. Then, the rotor 10 is magnetically attracted so that a part of the external surface of the cylinder may always come in contact with the rolling surface 3 of the stator 1, and a female screw 35 is formed in the central section. Besides, a male screw 36 for an output shaft 15 penetrates the rotor 10, and is supported by a cover. In this state, when the coils 50-53 are electrically conducted, then the yokes 60-63 are magnetized, and the rotor 10 is rotated coming contact with the rolling surface 3. As a result, the rotation is turned into screwing motion for applying thrust to the male screw 36 via the female screw 35 of the rotor 10, and the output shaft 15 can be rotated.

Description

Detailed Description of the Invention "Field of Industrial Application" This invention integrates an electric motor and a linear motion mechanism to linearly drive a driven object by converting the rotational motion of an electric motor into linear motion. This relates to a convenient electric actuator.

"Conventional technology" As a mechanism for converting the rotational motion of an electric motor into linear motion,
Conventionally, in most cases, the rotation of the electric motor is reduced by a speed reducer,
A mechanism was used in which the transmission was transmitted to the l11t screw or male screw, and the male screw that engaged with the female screw changed the relative relationship with the female screw.In addition, such electric motors, reducers, and female screws The mechanism consisting of the following has been integrated to make it convenient to use.

Electric actuators are also commercially available.

The present invention aims to improve such a conventional electric actuator and provide an electric actuator that is inexpensive and has a simple structure.

``Problems to be Solved by the Invention'' As mentioned above, conventionally used electric actuators reduce the rotation of the electric motor with a reducer, rotate a male or female screw, and rotate a female or female screw that engages with this. is based on a mechanism in which the male screws shift their relative relationship.

For this reason, a reduction gear is required, making the mechanism complicated, expensive, and the device large.

It takes up a lot of space to install and requires a large amount of 2M, and it has been desired to improve these drawbacks.

"Means for Solving the Problem" The present invention does not require a speed reducer in principle, unlike conventional methods.

In conventional motors, the rotor of the electric motor rotates around a fixed central axis.

In such an electric motor, the gap in the radial direction between the stator and the rotor is constant regardless of the rotation of the rotor, and is referred to as a constant gap type electric motor.

In the electric motor used in the present invention, the rotor rotates by rolling on the inner circumference or side surface of the stator.

This kind of electric motor has a structure in which the rotor of the electric motor rolls on the inner circumference or side surface of the stator.

The gap in the radial direction between the stator and the rotor, or the gap between the rolling surface on the side surface of the stator and the rotor changes as the rotor rotates.

In contrast, the stator and rotor of a general electric motor always rotate at a constant interval, that is, the rotor rotates at a constant relative position to the stator.

In order to distinguish between such a general fixed gap type electric motor and the electric motor used in the present invention, the two electric motors used in this specification will be referred to as variable gap type rotary electric motors.

A characteristic of such a variable gap rotary electric motor is that the rotor rotates with respect to the stator while making a grinding motion, but the rotational displacement of one rotor with respect to the stator for the grinding motion of one rotor is as follows. It is much smaller than the number of miso grinding motions (this relationship will be explained later), and is equivalent to the rotation of one rotor in a general fixed-gap electric motor when it is reduced using a high reduction ratio reducer. Become.

In the present invention, a variable gap type rotary electric j! Use 4.

A female thread is provided at the center of a rotor that rolls and rotates, and a male thread that is inserted into and engaged with the female thread passes through a variable gap rotary electric motor to form an output shaft for output,
The ltlt screw rotates eccentrically around the output male screw, and when the female screw rotates once around the male screw, the male screw advances one pitch, and it has a reducer without a reducer. It was made to have the same thrust effect.

The two rotors of the variable gap rotary electric motor of the electric actuator according to the present invention rotate in a shearing motion between the rotor, the female thread, and the male thread.

Since the male screw must be displaced with respect to the stator while keeping its axis constant, two forms are conceivable for engaging the male screw.

That is, the first type is such that the rotor and the female screw are fixed, and the male and female screws loosely engage with each other and perform a screwing action while absorbing the sliding movement. Although this form has an extremely simple structure as described later, the life of the female screw cannot be expected to be very long.

In the second form, the female thread and the male thread are tightly engaged, and the female thread and the rotor are loosely engaged, allowing rotation to be transmitted.The manufacturing cost is reduced between the female thread and the rotor. However, the lifespan of the female and male threads will be longer.

The present invention basically does not require a speed reducer, and since the male output screw is provided through the 9 rotors, the entire structure is compact and the shape is centered on the motor. It is rational because the output male screw is located, and the structure is simpler and easier to manufacture than conventional ones, and it is also highly efficient.

"Operation" The operation of the present invention will become very clear by explaining the embodiments, so I would like to explain the operation while explaining the embodiments.

Embodiment FIG. 1 is a cross-sectional view of a preferred embodiment of the present invention, and FIG. 2 is a cross-sectional view of the preferred embodiment of the present invention.

In order to facilitate understanding, the explanation will be made using two drawings, one above the other, one above and one left and right. In actual practice, it goes without saying that even if the device is inverted, left-right symmetrically turned over, etc., the structure does not deviate from the essence of the invention.

FIG. 1 shows a stator. The inside of the stator is cylindrical and forms two rotor chambers 2, and the inner surface of the two cylinders forms a rolling surface 3.

The stator 1 is made of soft magnetic material.

Inside the rotor chamber 2 of the stator l, there are 9 as shown in the figure.
A disk-shaped rotor 10 is attached to the cylindrical white ball.

In the case of the rotor 10 shown in FIG. 1, the rotor 10 is made of a soft magnetic material.

Coils 50, 51, 52, and 53 degrees are attached to the stator.

To explain how the coils 50, 51, 52, and 53 are installed, the stator 1 has coils parallel to the cylindrical direction of the rotor chamber 2.
Through holes 55, 56, 57, and 58 are provided through the stator (parallel to 1!II9 rotor chambers 2) so as to equally divide the circumference of the stator 1.

A yoke 60 is formed between the through holes 55 and 56 of the stator 10 as shown in the figure, and a yoke 61 is similarly formed between the through holes 5 and 57. Between the through holes 57 and 58 is the yoke 622 through hole 5
A yoke 63 is formed between 8 and 55.

The coil 50 is wound around the yoke 60.

Similarly, the coil 51 is provided to surround the yoke 61, the coil 52 to surround the yoke 62, and the coil 53 to surround the yoke 63, as shown in the two figures.

In the example of FIG. 1, the number of coils and yokes is four, but the number may be different from the two embodiments, such as 3, 5.6, etc.

Generally speaking, if the pitch of the power feed to the electrical coil does not change as the number of coils and yokes increases, then 9
Similar to a constant gap type electric motor, the number of rotations of the rotor 10 is slow and the number of rotations of the two rotors 10 relative to the stator 1 is also small.

The outer diameter of the rotor 100 cylinder is slightly smaller than the inner diameter of the rotor chamber 2.

The rotor 10 is provided so that it can freely move in the radial direction, but not in the direction of the axis (that is, in the left-right direction in FIG. 2).

As an example of such a means, a means as shown in FIG. 2 is used.

20.21 in FIG. 2 are covers, which are provided on the left and right sides of the stator l in FIG.

between the stator 1 and the cover 20 or 21.

As shown in the figure, a group of a plurality of balls 2B or 29 supported by a retainer 22 or 23 is provided just like the balls and retainers in a flat surface thrust ball bearing.

Reference numeral 24 indicates a strange ring provided on the cover 20.

Similarly, 25 is a bearing ring provided on the cover 21;
Reference numerals 6 and 27 denote bearing rings of the balls 28 and 29 provided on the left and right end faces of the rotor 10 in FIG. 2, respectively.

In this way, when the bearing rings 24, 26 and the balls 28 form a flat-faced thrust ball bearing, and the rolling surface of the balls is made flat, the bearing rings 26 are It is well known that the thrust force can be supported without any problem even during motion.

The relationship between the bearing rings 25, 27 and the balls 29 is also the same as described above.

Therefore, the 9-rotor IO can move in the plane (radial direction) direction in the state shown in FIG. The size of the inner diameter of the rotor chamber 2 influences the speed of rotation of the two rotors 10, and is important from the viewpoint of the function of the electric actuator of the present invention, as will be described later.

The rotor 10 is made smaller than the rotor chamber 2, and when this variable gap is used as a rotary electric motor, a part of the cylindrical outer surface of the rotor 100 is always connected to the rolling surface 3 of the stator 1.
9 The center 90 of the rotor chamber 2 becomes magnetically attracted so that it is in contact with the center 90 of the rotor chamber 2.

The centers 91 of the rotor IO do not coincide like in a normal electric motor.

A female thread 35 is provided at the center of the rotor IO so as to be widened from the outer periphery of the seven rotor IO.

In addition, the output shaft 15 for the output of the dynamic actuator of the present invention
As shown in FIG. There is.

The male thread 36 is further restricted from making two turns when viewed from the central axis.

As a concrete means for this, as shown in FIGS. 3 and 4, a keyway 37 is provided parallel to the central axis of the male screw 36, and a key is inserted into both the cover 20 or 21 or 20. Conventionally known means, such as providing a

As a means for suppressing the rotation of the male screw 36, the driven side on which this electric actuator is used is used. For example, the connecting fitting 70 at the end of the male screw 36 suppresses rotation in relation to the driven object. It is also possible to do so.

The pitch of the female screw 35 and the male screw 36 provided on the rotor 10 are set to be the same.

Further, the diameters of the male thread 36 and the female thread 35 are set so that the upper part of the male thread 36 overlaps the upper part of the female thread 35 when the lower end of the rotor 10 contacts the rolling surface 3 of the stator 10 in FIG. (In other words, the thread diameter of the # screw 35 is made larger than the thread diameter of the male thread 36 by approximately twice the eccentricity x.) Now, as shown in Figure 1. As shown, since the outer diameter of the rotor 10 is smaller than the diameter of the rolling surface 3, two rotors 10
There is a gap 92 between the upper part of the roller and the rolling surface 3.2 On the other hand, since the tit screw is provided wide on the rolling surface 3,
Its center is the same as the rolling surface 3 and is located at the position shown in FIG. 190.

The center 91 of the rotor 10 is located at the center 91 of the rotor 10 in FIG.
Since it is in contact with the rolling surface 3 below, it is located below half of the gap 92. l! The second rotor 10 is eccentric by half the diameter difference with the rolling surface 3.

This deviation Zζ amount will be referred to as X for ease of explanation.

The male thread 36 and the female thread 35 are also eccentrically provided by the same amount X.

The operation of such a structural configuration of the present invention will be explained.

In FIG. 1, when the coil 5.0 is energized and the yoke 6o is magnetized, the rolling surface of the yoke 60 attracts the rotor 1o.

Then, the lower part of the 9 rotor 10 is the rolling surface 3 before energization.
The one that was in contact with the left end 10 while rolling on the rolling surface 3
The two parts will now touch each other.

Next, when the coil 51 is energized, the yoke 61 is magnetized and the portion of the two-rotor 10 shown in FIG.
It moves while rolling on the rolling surface so that it is in contact with .

This movement causes the center of the rotor 10 to move to the left in FIG. 1 by an amount g, but the rotation of the two rotors 10 relative to the stator 1 becomes extremely small.

This 100 revolutions of the rotor causes the female screw 35 to exert a hexing action on the male screw 3G, and gives thrust to the male screw 36.

In this way, from coil 50 to coil 51°52.5
3, and as the current is continued, the first rotor 1o rotates while rolling on the rolling surface 3.

The motion of this rotor lO is 2. The center of the rotor 10 is the stator lO.
This is a sliding motion that is separated from the center of the rolling surface 3 by an amount of eccentricity.

The rotation of the rotor 10 is determined by the difference between the diameter of the rolling surface 3 of the stator 1 and the outer diameter of the rotor 10.

The rolling motion of the rotor 100 on the rolling surface 3 causes the coil 50. 51, 52, 53°, 50, etc. is equal to the rotational speed N of magnetization that is magnetized one after another.

If the diameter of the rolling surface 3 is R, and the diameter of the two-rotor 10 is r, then the number of revolutions n of the two-rotor 10 relative to the stator l is:

ngon NX(R-r)/R becomes.

Here, R = rolling surface; diameter of 3.

r = diameter of rotor io.

The number of rotations n is 1. For example, the diameter of the rolling body 3 is 100 m.
m, and if the diameter of the rotor lO is 99 mm, it will be 1/100 of the magnetization rotation speed N.

In a general induction motor, the magnetization rotation speed is 10
Since the rotation speed is usually , the rotor 10 described in
The relationship between the rotation of the stator l and the rotation of the stator 2 is as if the rotation was greatly slowed down compared to the rotation of a normal electric motor.

Furthermore, when looking at the magnetic action between, for example, the yoke 60 and the rotor 10, the lines of magnetic force occur in the horizontal direction in FIG. The direction in which the stator I attracts the rotor 10 is also the same horizontal direction.

That is, such a variable gap rotary electric motor is operated by a force normal to the lines of magnetic force.

In a normal electric motor, that is, a motor in which the rotor rotates with the center of the stator coincident with the center of the rotor (constant gap type), the normal force to the lines of magnetic force does not generate rotational force. Either the force is used as a diagonal component force, or two windings are provided on the rotor, and the magnetism of the stator acts on this winding, resulting in a force based on Fleming's left-hand rule.

As mentioned above. It is well known that the force due to the normal force to the lines of magnetic force in a variable gap rotary motor is several times stronger than the force due to Fleming's left-hand rule in a general induction motor at the same magnetic flux density.

In other words, compared to a normal electric motor in which the stator and rotor rotate together, a variable gap rotary electric motor rotates slowly and generates a large rotational force. It has a function.

However, the rotor 10 of the variable gap rotary motor
rotates with a shearing motion, so a mechanism that extracts this as rotational motion is difficult and has a long life, and it has the disadvantage that it is not easy to obtain one with little vibration.

In the above-described examples of FIGS. 1 and 2 of the present invention, the above-described mechanism for extracting the rotation of the rotor 10 is unnecessary, and the mechanism is extremely simple and simple. In other words, the two-rotor 10 is rotated by the female screw 3 rotating around the outside of the male screw 36.
In the structure of 5, 100 rotational forces of two rotors are transmitted to the male screw 36 and converted into propulsive force of the male screw 36.

That is, the female screw 35 moves around the male screw 36 with an eccentric amount X. At this time, due to the transfer of the rotor 10, the rotational positions of the male screw 36 and the female screw 36 change relative to each other.

Since the rotation of the male screw 36 is suppressed as described above, the male screw 36 moves in the left-right direction in FIG. 2.

In this way, the male screw 36 generates a thrust force against the stator 1, and the order of excitation of the coils is reversed to 50.53, 50.
2, If you do it like 51.50.

The male screw 36 moves in the opposite direction to the above, and the male screw moves by controlling the excitation order of the coils 50, 51, 52, and 53.
It moves under control in the left-right direction in FIG.

The male thread 36 and the female thread 35 may have any conventionally known form that has a relationship between a female thread and a male thread, but
It is preferable to use a ball screw as the female screw 35 because it is highly efficient and has a long life.

Also, a roller screw similar to a ball screw can be usefully used.

In order to roughly reduce the wear of the male screw 36 and female screw 35, as shown in FIG. Even if they are arranged around the screw 36, the same dual action function as the female screw 35 can be obtained.

That is, in FIGS. 5 and 6, the shaft 120 is provided at the center of the male screw 351, and the two-rotor 10 is provided with holes 111 and 112 into which the shaft 120 is mounted, so that the male screw 351 can be rotated. It is installed.

Similarly, the male screw 352 is provided with a shaft 121 and is attached to the holes 113 and 114 provided in the two rotors 10,
The f111 screw 353 is provided with a shaft 122 and the two rotors 1
It is installed in the holes 115 and 116 provided in the
54 is provided with a shaft 123 and a hole 117 provided in the two rotors 10 . It is attached to lu8.

Holes 111, 113, 115, 117 and hole 112.1
14, 116, and 118 are provided on the outer periphery of the rotor 10 and the wide open circle, and 1, for example, a male screw 3, as shown in FIG.
When the gap 92 existing on the radial extension of the output screw 352 is at its maximum, the male screw 352 fits snugly into the output male screw 36.

The male screws 351, 352, 353, and 354 rotate slightly when engaged with the male screw 36, thereby reducing wear. Also male screws 36 and 351, 352, 353
, 354 is easy to work with and can use a material with high hardness, so wear can be reduced.

The present invention can be made more effective by substituting a female screw consisting of a plurality of male screws, such as the male screws 351, 352, 353, and 354.

As stated at the beginning of this specification, the electric actuator according to the present invention is characterized in that even without a reduction gear, it provides the same action and effect as an electric actuator using a conventional reduction gear. They were arranged like planets around the external male screw 36 as shown in FIGS. 7 and 8. Male thread 365
, 366.367.368 with a simple gear mechanism 2
By allowing the rotor to rotate relative to the rotor IO, it is possible to provide even more advanced functions and make the present invention even more useful.

That is, as shown in FIGS. 7 and 8, the male screws 365, 3
66, 3 E; 7, 3 G Gear 37 on the left and right of 8
1.372.373, 374.375, 376.377
．． 378 respectively provided on the two rotors 10.
Set it so that it meshes with 0,381.

Male screws 365, 366, 367, 368 are cage 340
, 341, they are connected like the needles of a needle bearing.

When creating such a structure, use a male thread of 365.36
6.367.36Fl operates like a floating star that revolves while rotating, and simply has a male screw of 361°362.363,3
64 rotates according to the output male screw 36, a different movement of the male screw 36 is obtained.

That is, if the rotor 10 is currently stopped and the male screw 365
, 366, 367, and 368 each turn once, it is easy to understand that the output male screw 36 advances by one pitch.

Therefore, if the male screws 351, 352, 353, and 354 rotate once counterclockwise while the two rotors lO rotate once clockwise, the output male screws 36 are completely relative to the rotor 10. It never changes its position.

Gear 37], 372.373, 374.375.376
．． Diameter of tooth surface of 377.378 and gear 380.381
The diameter of the tooth surface of ! If you choose properly.

For one rotation of the rotor 10, the male threads 365, 366 .
367.368 can be rotated by one rotation and +α.

If this +α is smaller than one rotation, then Fig. 1.

Compared to the one in FIG. 5, when the rotor rotates 100 times, the moving speed of the output male screw 36 becomes slower and the thrust becomes larger.

Further, when +α is larger than one revolution, the thrust of the output male screw 36 is smaller than that of FIGS. 1 and 5, and the speed of deviation becomes faster.

As a modification of the female screw 35, as shown in FIG.
A similar effect can be obtained by arranging a plurality of roller bins 130 that fit into the threads of No. 6 on the rotor 10 in the radial direction.

FIG. 9 is a cross-sectional view of a Japanese currency made in this manner.

Reference numeral 131 in FIG. 9 is a needle bearing that supports the roller bin 130.

The structural configuration shown in FIG. 9 is efficient because the roller bin easily rolls on the threads of the output male screw 36.2 In the variable gap rotary electric motor used in the present invention, the interior of the rotor 10 is wide. , a roller bin 1 as shown in FIG.
30 and the needle bearing 131 can be easily installed and are a preferred embodiment.

In the example of FIG. 9, bearing rings 24 and 25 are connected to rotor 1 by two disc springs 75, 76 and 77, 78 as shown.
It is designed to press toward 0.

The bearing rings 24 and 2 also pass through the cover 20.21.
5 to actuating rods 82.8 of limit switches 80 and 81.
3 are in contact with each other.

With this structural configuration, if an excessive thrust is applied to the male screw 36 from the outside, the bearing ring 24 or 25 will be pushed through the screw 35, the limit switch 80 or 81 will be activated, and the male screw 36 will be subjected to an excessive thrust. It is possible to sense that a strong thrust has been applied.

Since the rotor 10 makes a sliding motion on the rolling surface 3, it imparts vibrations to the stator 1, which in turn causes vibrations to be imparted to the outside of the electric actuator, which may cause problems.

In such a case, it is conceivable to balance the vibrations of the two rotors by arranging variable gap rotary motors in a skewer shape as shown in FIG.

That is, in the center of FIG. 10, 1 is a stator.

10 is a rotor 1 There is a female screw 35 in the center of the rotor 10.
This is the same as in FIGS. 1 and 2 in that a male thread 36 is provided passing through the center of the female thread 35.

A stator 401 is further provided on the right side of the cover 20, and the stator 4. A rotor 410 is provided inside the Ol.

The rotor 410 and the rotor 10 are mounted 180 degrees apart from each other on the rotation plane of the rotor 100. In other words, in FIG. Although the rotor 410 is located, the gap is the rotor 410
It's below.

A stator 501 is also provided on the left side of the cover 21.

A rotor 510 is mounted inside.

Similarly to the rotor 410, the rotor 510 is mounted 180 degrees apart from the two rotors 10.

In such a structural configuration, two rotors 10 and 410
When the rotor 10 and the rotor 410 and 510 perform a grating motion and a rotating motion, the directions of vibrations caused by the motion of the rotor 10 and the rotor 410 and 510 are opposite to each other, so the vibrations interpolate with each other, and the vibrations to the outside are will disappear.

As shown in the figure, the rotors 510 and 410 are hollow inside and have a dragon of inertia similar to the rotor 10.

Although the structural configuration shown in FIG. 10 appears to be 1 m long, the stators 1,401,501 may have the same shape and structure, and the nine rotors 10,410,510 may also have the same structure.

Therefore, a product with such a structure is inexpensive and has a 5.
It's easy to make one. Moreover, even if the outer diameter of the stator I, 401, 501 is made thinner, the output is strong, the stator is small, and the outer diameter is well-organized.

The female screws attached to the rotor 10 and the male output screws 36 are other than those described above.

The essence of the present invention is not impaired even if any conventionally known screw mechanism is used, and any screw mechanism can be used as long as it is efficient.

It was. In the above explanation, the thread diameter of the female thread 35 is smaller than the thread diameter of the male thread 36 on the rolling surface 3 of the stator l and the rotor 1.
A structure in which the eccentricity is increased by twice the amount of eccentricity of 0 has been explained.

Such a structural configuration is an extremely simple and inexpensive electric actuator and is a useful embodiment of the present invention, but the lifespan of the female screw 35 relative to the male screw 36 is longer than that of a normal screw.
, it gets cheaper.

In FIG. 11, the male thread 36 and the female thread 35 are tightly engaged like a normal screw, that is, tightly engaged, and a spline is formed between the outer periphery of the female thread 35 and the inner periphery of the two-rotor 10. The 1llt screw 35 is provided at a constant (1j) position, so that even if the rotor 10 moves around it, the rotation is transmitted to the female screw 35 without any problem, and the life of the threaded part is short. long.

In FIG. 11, the spline has a structure in which there is some play in the radial direction of the female thread 35, but there is no problem with transmission to the rotating female thread 35 of the two-rotor 10. Floating Connection Method 2 For example, conventionally known means used in Oldham's joints and the like can be used as the structure for engaging the rotor 10 and the female screw 35.

Further, it is conceivable that slip (sliding phenomenon) may occur between the rolling surface 3 of the stator 1 and the outer surface of the rotor IO that comes into contact with the rolling surface 3.

This slip phenomenon may work favorably for the electric actuator of the present invention, and depending on the intended use.
There are some cases where it is not desirable.

That is, an external force acts on the output male screw 36, and the male screw 36
When the movement in the left and right direction in FIG.
A phenomenon occurs in which the object separates from the object and rotates in the air.

This phenomenon occurs if the rotor 10 stops rotating and an alternating current is flowing through the coil.

A large overcurrent will flow and the coil will burn out.

When the rotor 35 idles, the current flowing through the coil is less than when the rotor 10 is stopped, which has the effect of reducing coil burnout, but on the other hand, such a phenomenon is a problem from accurate rotation. In other words, when the displacement of the output shaft is determined by an electric signal applied to a coil as in NC control, the slip phenomenon becomes a problem in terms of accuracy.

In such a case, the rolling surface 3 or the rolling surface 3 of the rotor 35
Possible options include using a material with high friction for the surface in contact with the surface, providing unevenness, providing gears, or staggers.

In this specification, the variable gap rotary electric motor has been described as having a structure in which the magnetism generated by the coils 50, 51, 52, and 53 attracts the rotor via the yoke. However, it is also possible to embed a magnet in the 7-rotor 10 or to make the 9-rotor 10 itself a magnet, and to utilize the magnetic attraction generated by the coil. There is also a variable gap rotary electric motor that utilizes the principle of structure for generating an attractive force, and such a variable gap rotary electric motor having a known structural configuration is used as the electric motor of the electric actuator according to the present invention.

The present invention can be used with any variable gap rotary motor having such a known structural configuration.

A variable gap rotary electric motor different from the examples shown in FIGS. 1 and 2 was used. A preferred embodiment will now be described.

In the explanation so far, the rolling surface 3 of the variable gap rotary motor is a cylindrical surface inside the stator I.

On the other hand, a variable gap rotary electric motor in which the side surface of the stator 1 is a rolling surface is also known.

FIG. 12 is a cross-sectional view of an example of an excellent electric actuator that is made by skillfully utilizing such a known variable gap rotary electric motor.

FIG. 13 is a cross-sectional view taken along the line A-B-C-D in FIG. 12.

In FIGS. 12 and 13, 201 is a stator, but unlike the example in FIG. 1, it is not 15. It is made up of sexual bodies.

With the stator 201 in between, rotors 210 and 211, which are disc-shaped and made of soft magnetic material, are provided on the left and right sides of the stator 201, as shown in the two figures.

The stator 201 has a yoke 2 [30
is buried, and a coil 250 is attached to the yoke 260. As shown in the figure, the yoke 260 and the coil 250 are arranged such that the coil 250 is provided at the center of the yoke 260 so as to surround the yoke 260.

Similarly, 261, 262, 263 are yokes made of soft magnetic material, and each yoke 261, 262, 26
Coils 251, 252, and 253 are attached to the coils 3 and embedded in the stator 201, respectively.

Rotor 2 on the left and right sides of the stator 201 in FIG.
The portions facing 10 and 211 have a cone shape as shown in Figure 2, forming rolling surfaces 203 and 204.

In the middle of the yokes 260, 261, 262, 263, there is an auxiliary yoke 265°266.267 made of soft magnetic material.
．． 268 is embedded in the stator 201 as shown in the figure, and its left and right end surfaces in FIG.
It is made so that it is on the same plane as the

When the coil 250 is energized, the generated magnetism passes from the yoke 260 to the rotor 2.10 and then to the auxiliary yoke 265.
, 268 and returns from the two rotors 211 to the yoke 250, and the yoke 250 and auxiliary yoke 265
, 268 attract the two rotors 210, 211 to the stator 2010 rolling surfaces 203, 204.

The surfaces of the rotors 210 and 211 facing the rolling surfaces 203 and 204 form a cone at a slightly deeper angle than the cones of the rolling surfaces 203 and 204, and rotate at the bottom of the stator 201 as shown. When the children 210 and 211 contact the stator 201, the angle is such that there is a gap between the rolling surface 203 of the stator 2010 and the rotor 210 at the upper part of the stator 201.

Further, the relationship between the rolling surface 204 of the stator 20 and the rotor 211 is also the same as above.

235 is a female screw, which connects the rotor 210 at the center of the stator 201.
. It is provided so as to suppress movement in the direction.

The outer periphery of the female thread 235 and the part of the inner hole that fits into the female thread 235 of the nine rotors 210 and 211 are loosely fitted, and as shown in FIG. , * was provided in the direction of the axis of the screw 235. A groove 230 with a semicircular cross section and one rotor 210, 21
As shown in the figure, tM231, 232 having a semicircular cross section provided in the direction of the axis of the female thread 235 are engaged with the inner periphery of the inner hole of 1 (just like a type of adjustable joint) The rotation of the rotors 210, 211 is transmitted to the female thread 235 by means such as those shown in FIG.

The state of the rotor 210, 211 shown in FIGS. 12 and 13 is similar to the state when the coil 252 is excited and attracts the rotor 210, 211.
01 and the rotors 210 and 211 are in contact with each other.

Next, when the coil 253 is energized, the yoke 263 attracts the rotors 210 and 211, and then when the coil 250 is energized, the yoke 260 attracts the rotors 210 and 211. (At this time, the stator 201 and the rotors 210, 211
12 and 13) In this way, the coils 252 to 253, 250,
251. 252. 253.・ ・ ・ ・
By repeating the excitation and de-energization, the rotors 210 and 211 rotate on the rolling surfaces 203 and 204 while making a rocking motion.

The rotational displacement of the rotors 210, 211 with respect to the stator 201 is caused by one rotor 210, 211 rolling on the rolling surface 210, 204 of the stator 201, but the rolling surface 210, 211
Average rolling length of 03,204.

l7=2π (R+2b) Here.

R = Inner diameter b of the rolling surfaces 203, 204 = 1/2 of the width of the rolling surfaces 203, 204 in the radial direction (i.e., the distance from the circumference of the inner diameter R to the average rolling line). When the cone angle of the surfaces 203 and 204 is close to 180°, the two-rotor 210 and 211 are shortened as the cone angle becomes deeper.
The average rolling length l of 211 is 1=2π(R+2bCos
α) Here.

α: It is the angle of the difference between the cone angles of the rolling surface 203 or 204 and the rotor 210 or 211, therefore.

The rotation speed n of the rotors 210 and 211 is.

n=NX (R+2b)/(R+2bCosa).

Therefore, the rolling surface 203 or 204 and the two rotors 21
The smaller the difference α between the cone angles of 0 and 211, the slower the number of rotations n of the two rotors 210 and 211 relative to the number of magnetic turns N.

This type of variable gap rotary electric motor is shown in FIG. In the case with the radial gap, the large inertial body of the rotor 10 moved eccentrically, but in the case shown in Fig. 12, there is almost no eccentricity, so if the difference in cone angle is extremely reduced, the two-turn torque is strong. This is a variable gap rotary electric motor with a slow rotation speed and little vibration.

Moreover, what is shown in FIGS. 12 and 13.

Since two rotors 210 and 211 are provided on the left and right sides in FIG. 12, vibrations based on the rocking motion and rotational motion of the two rotors 210 and 211 are in opposite directions (left and right in FIG. 12). The vibration is canceled out, resulting in quiet operation.

Coils 250, 251° 252 in FIGS. 12 and 13.
253 or the coil 50, 51, 52, 53 of the one in Figure 1
For example, the coil and yoke may be made of three poles, and each phase of a three-phase alternating current is supplied to each coil in order of cycle.

By using means such as creating a rotating magnetic path, by making the coil and yoke into 6 poles, and using each phase of 3-phase AC as the main circuit, the following:
j: Each phase is applied to three coil groups at once.
The coils of the saw pair are branched from the main circuit; the three-phase alternating current may be delayed and fed through a delay circuit. In addition, the coils 50, 51, 52, 53 using a control device for power supply
You may also try blowing and kicking.

As in a DC motor, the brushes are interlocked with the two rotors 1o, and power is thereby supplied to the coil through contact pieces.The variable gap rotary motor uses the same means of power supply to the coil as is used in general fixed gap motors. It can also be used to suitably power a coil.

All of these can be used as a variable gap rotary motor of the electric actuator of the present invention depending on the purpose.

[Effects of the Invention] With the structural configuration of the present invention, the torque of the rotor of the powerful variable gap rotary electric motor can be utilized, so a small and powerful electric actuator can be used.

In addition, the rotor of the variable gap rotary motor rotates slowly while making a sliding motion, which rotates the female screw and feeds the engaged male screw, so there is no need for a speed reducer in principle, and there is no need for a conventional fixed It has a simpler structure and is easier to manufacture than an electric actuator that uses a gap-type electric motor and a speed reducer, and can therefore be manufactured at a lower price.

The reason why the present invention is a particularly useful mechanism is that when the deviation aX is made small, that is, the diameter of the rotor 10 is made slightly smaller than the diameter of the rolling surface 3, the 100 rotations of the rotor are decelerated relative to the magnetic rotation. As the ratio becomes larger and the magnetic force that attracts the rotor 10 also becomes smaller, the distance becomes smaller.
The torque increases in inverse proportion to the multiplication factor, and has a double effect: the rotational torque of the rotor 10 of the variable gap rotary motor increases, and the deceleration effect of the rotor 10 increases.

In addition, since there are no gears in principle and the two rotors rotate around the output male screw, there is less noise and the efficiency is high.Even in systems that use gears, the configuration of the gears is simple and the noise is reduced.

Furthermore, the appearance is naturally simpler and smaller than the conventional fixed-gap electric motor and reducer.
As can be easily inferred, it is clear that 2 weights are also reduced. In fact, some electric actuators designed according to the present invention have a weight that is approximately 1/2 that of conventional ones.

The simple appearance and small size make this type of actuator suitable for use in industrial machinery, etc.

It is extremely easy to install and can be manufactured lightweight, which is a long-awaited function for industrial robots. In addition to being inexpensive, it has the advantage of being small and lightweight.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of one embodiment of an electric actuator according to the present invention. FIG. 2 is a sectional view of the one shown in FIG. 1. FIG. 3 is a cross-sectional view of a portion of the electric actuator according to the present invention that prevents the output male screw 36 from rotating twice. Figure 4 is a cross-sectional view of one Japanese currency from Figure 4. Figure 5 shows multiple male screws 351.35 instead of female screws 35.
2,353,354 are arranged around a male screw 36 for output. FIG. 6 is a partial cross-sectional view of the one shown in FIG. 5. FIG. 7 is a cross-sectional view of a plurality of male screws 365, 366, 367, and 36 [3] arranged around the output male screw 36 and provided with a gear that provides rotation. FIG. 8 is a partial cross-sectional view of the one shown in FIG. 7. FIG. 9 is a cross-sectional view of one Japanese currency using a roller bin 130 instead of the female screw 35. FIG. 10 is a sectional view of a variable gap rotary motor provided in a skewer shape. FIG. 11 is a partial cross-sectional view of a female screw 35 and a male screw 36 that are tightly engaged. FIG. 12 is a sectional view of an alternative type of electric actuator according to the present invention. FIG. 13 is a cross-sectional view of that of FIG. 12. next. 1 is a stator, 2 is a rotor chamber, and 3 is a rolling surface. 10 is a rotor. 15 is the output shaft. 20.21 is a cover. 22.23 is the retainer. 24.25, 26.27 are bearing rings. 28.29 is a ball. 35 is a female screw. 36 is a male screw. 37 is a keyway, 38 is a key. 50.51, 52.53 are coils. 55.56, 57.58 are through holes. 60.61, 62.63 are York. 70 is a connection fitting. 75.76.77.78 are disc springs. 80.81 is a limit switch. 82.83 is the limit switch operating rod. 90 is the center of the rotor chamber 2. 91 is the center of the rotor 10. 92 is a gap. 101, 102, 103, and 104 are the outer surfaces of the rotor 10. 111.112, 113, 114, 115, 116.1
17 and 118 are holes. 120.121, 122, 123 are axes. 130 is a roller pin. 131 is a needle bearing. 201 is a stator. 203.204 is the rolling surface. 210.211 is the rotor. 220.221 is a cover. 222.223 is a bearing. 228 is a ball. 230.231, 232 are grooves. 235 is a female screw. 236 is a male screw. 250.251, 252, 253 are coils. 260.261.262. '263 is York. 2 b 5 + 266 + 2671268 is the auxiliary yoke. 340.341 is a cage. 351, 352, 353, 354 are male screws. 365.366.367.368 are male screws. 371.372, 373, 374, 375, 376.3
77.378 is a gear. :3B0.381 is a gear. 401 is a stator. 410 is a rotor. 501 is a stator. 510 is a rotor.

Claims (3)

[Claims] (1) In a variable-gap rotary motor in which the rotor rotates while sliding along a rolling surface on the inner periphery or end surface of the stator, the variable-gap rotary motor is penetrated through the center of the rotor, A thrust mechanism consisting of a male screw forming an output shaft and a female screw that engages with the male screw is provided, and the axis of the male screw is parallel to the axes of the rotor and stator. It is provided so as to be movable in the direction of the axis and restrained from rotating in the direction of rotation of the rotor, the female screw engages with the rotor, and the female screw is prevented from rotating. Movement in the direction of the axis of the child is suppressed, the female screw rotates due to the rotation of the rotor, and the male screw rotates in the direction of the axis of the stator with respect to the stator due to the screw action with the male screw. An electric actuator characterized by displacement in a direction. (2) At the center of the rotor described in paragraph 1, a female screw whose screw diameter is twice the eccentricity of the stator and rotor is fixed than the screw diameter of the male screw, and the female screw The first device is characterized in that the screw rotates around the male screw while making a grinding motion.
Electric actuator described in section. (3) The female thread and the male thread should be tightly engaged, and the outer periphery of the female thread and the rotor should be engaged loosely in the direction of the rotating surface and capable of transmitting rotation in the direction of rotation. The electric actuator according to item 1, characterized in that: