JPS60167672A - Motor - Google Patents

Abstract

PURPOSE:To obtain low speed and high torque by attracting a rotor by an electromagnetic force, and converting the force directly into a rotary force. CONSTITUTION:A rotor 10 is rockably held on the gear surfaces of a driven bevel gear 7 and a stationary bevel gear 8 via spherical bearings made of convex and concave surfaces 11a, 11b, and a thin disc-shaped electromagnetic attraction unit 12a is formed on the outer periphery. A plurality of electromagnets 13... are disposed on the outer periphery of the gear 8. When the electromagnets 13... are sequentially excited, the unit 12a of the rotor 10 is attracted, fluctuated, one bevel gear 9 of the rotor 10 is engaged in mesh with the gear 8 to rotate around its own aixs while rotating around the gear 8 along the tooth surface of the gear 8. Simultaneously, the other bevel bear 9b of the rotor is engaged in mesh with the gear 7 to transmit the rotary force to the gear 7.

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to a low-speed, high-torque small motor used mainly in robot arms, automatic doors, etc. The present invention relates to an electric motor that supports the rotor, attracts the rotor with electromagnetic force, and converts this electromagnetic force directly into rotational force to obtain low speed and high torque.

(2) Background of the Technology The general idea was that when a motor is used, its rotation speed is reduced or increased to obtain a torque suitable for the purpose. When a small, high-output motor is used, since there is a limit to the saturation magnetic flux of iron, it is necessary to increase the electromagnetic conversion energy by increasing the repetition rate of magnetization direction reversal. In this case, it means increasing the rotation speed, and
This means low torque. On the other hand, there are cases where low speed and high torque are required (for example, rotation of radar antennas, robot arms, automatic doors, etc.), and the rotation speed in these cases is said to be about 180 RPM, but on the other hand, large torque is required. is necessary. In order to obtain such high torque, it is usually possible to reduce the speed using a gear mechanism, but as the motor becomes smaller, its rated rotational speed becomes around 10,000 PPM, so this is reduced by the method described above. If you try to reduce the rotation speed, the reduction ratio will increase. As the reduction ratio increases, spur gears require multiple stages, and in order to satisfy the reduction ratio with one stage, a worm gear or the like must be used, both of which result in undesirable results such as increased friction loss. Furthermore, recently there has been a growing demand for miniaturization of the entire device in which the motor is incorporated, and as a result, a motor that can directly obtain torque suitable for the intended use has become desirable. Therefore, a single gear mechanism has come to be used as a gear mechanism that can achieve a large reduction ratio in one stage.

(3) Prior Art and Problems As shown in FIG. 1, the sinkle gear mechanism 1 has a driven bevel gear 2 and a fixed bevel gear 3 arranged substantially coaxially and facing each other. A rotor 4 having two bevel gears 4a and 4b interposed between the gear 3 and individually meshing with the gear 3 is supported by a drive shaft 6 via a bearing 5. This drive shaft 6 has a tilted shaft 6a at its tip, and when the drive shaft 6 rotates, the tilted shaft 6a performs a so-called conical scraping motion with respect to its central axis. Accordingly, the rotor 4 is configured such that one bevel gear 4a meshes with the fixed bevel gear 3 while swinging, and the other bevel gear 4b rolls while meshing with the driven bevel gear 2. . In this case, as shown in Fig. 2, the driving torque T on the tilting shaft 6a side is converted into a large force Fi=T/r on the rotor 4 at the extremely small rotation radius r, that is, at the tilting shaft 6a portion. However, this is the torque balance centered around the meshing point P with the fixed gear 3, that is, the rotation radius of the rotor 4 is R1, and the transmitted force at the meshing point Q with the driven gear 2 is FO, then the output is FiR=Fo・2R Torque FO・R=T/2r.

However, increasing the reduction ratio results in decreasing r and increasing Fi, and an extremely large force is applied to the inclined shaft 6a of the drive shaft 6, which may lead to abnormal phenomena such as prying. It was easy.

(4) Purpose of the Invention The present invention has been made to solve the above-mentioned problems.The rotor of a single gear is swingably and removably supported, the rotor is attracted by an electromagnet, and the electromagnet is directly connected to the rotor. The purpose of the present invention is to provide an electric motor that converts rotational force into low speed and high torque.

(5) According to the present invention, the structure of the invention and the above object are such that a stator and a follower are arranged on the same axis, and a part of the stator and follower are arranged on the same axis so that a part thereof is always in contact with the axis. A rotor that is held rotatably about the axis while tilted at a predetermined angle, and a plurality of electromagnets that are arranged around the rotor and rotate the rotor by sequentially energizing the rotor. This is achieved by providing an electric motor with

(6) Embodiments of the invention Hereinafter, embodiments of the invention will be described in detail based on the accompanying drawings.

FIG. 3 is an exploded perspective view of the electric motor according to the present invention, and FIG.
The figure is an explanatory diagram schematically showing this. First, the number of teeth ZI
The driven bevel gear 7 and the fixed bevel gear 8 having Z4 teeth are arranged coaxially or substantially coaxially with each other and facing each other. At an intermediate position between the driven bevel gear 7 and the fixed bevel gear 8, there are two bevel gears 9b and 9 having 22 teeth and 23 teeth, respectively, that mesh with these.
A rotor 10, which has letters a on both its front and back surfaces, is supported by a spherical bearing made up of convex spherical surfaces 11a of eight fixed bevel gears and concave spherical surfaces 11b provided on the rotor 10 side. The rotor 10 can swing relative to the gear surfaces of the driven bevel gear 7 and the fixed bevel gear 8 by the spherical bearing, and is provided with a thin disc-shaped electromagnetic attraction part 12 on its outer periphery. There is.

Furthermore, a plurality of electromagnets 13 are provided on the outer periphery of the fixed bevel gear 8.
．． 13,... are arranged, and these electromagnets 13
, I3. When .
It rotates while revolving along the tooth surface. At the same time, the other bevel gear 9b of the rotor 10 meshes with the driven bevel gear 7 in the same manner as described above to transmit rotational force to the driven bevel gear 7. In addition, in the above, the driven bevel gear 7, the fixed bevel gear 8, and the rotor 10 may each be a friction disk, and the convex spherical surface 11a and the concave spherical surface 11b of the spherical bearing supporting the rotor IO are as described above. Conversely, they may be provided on the rotor 10 and fixed bevel gear 8 sides, respectively. Furthermore, as in other embodiments to be described later, electromagnets 13, 13 .・
... may be provided on the inner circumference of the fixed bevel gear 8. In this case, the electromagnetic attraction portion 12 of the rotor 10 will naturally be provided at the corresponding inner peripheral portion. Furthermore, electromagnets 13, 13. . . . may be distributed between the outer circumference and the inner circumference of the fixed bevel gear and work together. In this case, the electromagnetic attraction part of the rotor 10 has a corresponding outer peripheral part,
It will be provided on both inner peripheral parts. This is shown in FIG. In FIG. 9, the inner and outer electromagnets 38 of the stator 40 are shown.
39 are arranged alternately, but they may be arranged on the same radial line. Incidentally, when using the configuration shown in FIG. 9, pulsation can be reduced.

To explain the operation of the electric motor of the present invention according to the above configuration,
In FIG. 4, electromagnets 13, 13. The adsorption force Fi due to... is the fixed bevel gear 8 and one bevel gear 9a of the rotor lO.
A moment is generated around the meshing point K between the rotor 10 and the driven bevel gear 7, and this generates a force Fo at the meshing point between the other bevel gear 9b of the rotor 10 and the driven bevel gear 7. In this way, the electromagnets 13, 13, ... are switched one after another to increase the speed, and even when the rotational speed of the magnetic field becomes NO, the actual rotational speed Nl of the rotor 10 is N, = NOX (21-24 )/Z3
This is further decelerated between the driven bevel gear 7 and its rotational speed N2 is NZ=NOX (122Za
/ZIZs).

Next, FIGS. 5 to 7 show other embodiments. First, in FIG. 5, a rotor 16 is supported between the driven bevel gear 14 and the fixed bevel gear 15, and 17 is an electromagnetic attraction plate 18.1B.

... is an electromagnet. In this embodiment, the rotor 16
is supported by an inclined shaft 19 and radial bearings 20 and 20. Further, FIG. 6 shows that the driven bevel gears 21, 21a and the fixed bevel gears 22, 22a are connected to a plurality of electromagnets 23, 23.
-... are provided on both the front and back sides of the same axis. Intermediately between the driven bevel gear 21 and the fixed bevel gear 22, and between the driven bevel gear 21a and the fixed bevel gear 22a, there are two bevel gears 24, 24' and 24a, 24a' that mesh with these on the front and back surfaces. The children 25 and 25a are respectively spherical bearings 26 and 26.
It is supported by a. And electromagnetic adsorption part 35.35a
are provided on the inner periphery of each of the bevel gears 24, 24' and 24a, 24a'.

In this case, the output shafts 21', 21'' are provided in both left and right directions.In addition, spherical bearings 26, 26
The shaft 27 forming the rotor a is a permanent magnet and has a holding force to support both the rotors 25 and 25a even during a power outage. Furthermore, in Figure 7, 28
．． 28. ... are electromagnets, and the rotor 29 has two bevel gears 32 and 33 on the same side that mesh with the driven bevel gear 30 and the fixed bevel gear 31, respectively. The driven bevel gear 30 and the fixed bevel gear 31 are connected to the bevel gear 32 of the rotor 29.
．． 33 side, and this bevel gear 32 and 33
An electromagnetic adsorption section 34 is provided between them. In this way, the entire electric motor is made more compact. FIG. 8 is an external view of the electric motor 11M according to the present invention applied to a robot arm. Such an electric motor M has 1ff36 between each
a, 36b.

36c and 36d, and rotate according to an external control command.

(7) Effects of the Invention Since the present invention is constructed as described above, the rotor of a single gear is supported in a swingable and movable manner, and the rotor is attracted by electromagnetic force, and this electromagnetic force is directly converted into rotational force. By converting, a low speed, high torque electric motor can be obtained. In addition, conventional small high-speed motors have a coil and a commutator in the rotor, and there is a risk of damage due to centrifugal force during rotation, but in the present invention, the coil is fixed, so the limit for high-speed switching of magnetic flux is extremely high. can do. Furthermore, the attractive force of the electromagnet against the rotor acts in the direction of pressing the spherical bearing or the radial bearing, so that no force that would strain the bearing is generated and the operation is smooth. Furthermore,
The fact that the actual rotational speed of the rotor is low means that the kinetic energy stored therein is low, and when viewed as a device that is placed close to humans, it is highly safe.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the sinkle gear mechanism, Fig. 2 is an explanatory diagram showing its force relationship, Fig. 3 is an exploded perspective view of the electric motor according to the present invention, Fig. 4 is a schematic explanatory diagram thereof, and Fig. 5 is an explanatory diagram of the electric motor according to the present invention. A cross-sectional view when the rotor is supported by an inclined shaft and a radial bearing. Figure 6 is a cross-sectional view when the rotor is symmetrically installed with the shaft extending from both sides. Figure 7 is a driven gear and a fixed gear. FIG. 8 is an external view when the electric motor of the present invention is applied to a robot arm, and FIG. 9 is a diagram illustrating the arrangement of electromagnets. 7.14, 21.21a, 30 = driven bevel gears 8.15, 22, 22a, 31... fixed bevel gears 9a, 9b, 24.24', 24a, 24a'. 32.33...Bevel gear 10.16, 25, 25a, 29...Rotor 11a.
...Convex spherical surface 11b...Concave spherical surface 12.1? , 34.35, 35a --- Electromagnetic adsorption portion 13.18, 23.28... Electromagnet 19... Inclined shaft 20... Radial bearing 26.268... Spherical bearing 27... Shaft applicant Fujitsu Ltd. Figure 1 Figure 2 Figure 3] O Figure 4 Figure 6 Figure 7

Claims (1)

[Scope of Claims] 1. A stator and a follower disposed on the same axis, and the shaft tilted at a predetermined angle with respect to the axis so that a part thereof is always in contact with the stator and follower. An electric motor includes a rotor rotatably held around a rotor, and a plurality of electromagnets arranged around the rotor and sequentially excited to rotate the rotor. -2. The electric motor according to claim (1), wherein the stator, follower, and rotor are bevel gears. 3. The electric motor according to claim (1) or (2), wherein the rotor is supported by a spherical bearing. 4. The electric motor according to claim 1 or 2, wherein the rotor is supported by a combination of an inclined shaft and a radial bearing. 5. The driven element and the stator are provided on both sides of the electromagnet, and a rotor is supported between the driven element and the stator so as to be able to swing and move in contact with them. An electric motor according to claims (1) to (4). 6. Claim (1) characterized in that the follower and the stator are arranged on the same side of the rotor.
The electric motor described in paragraphs to (4).