WO1986005634A1

WO1986005634A1 - Geared motor

Info

Publication number: WO1986005634A1
Application number: PCT/JP1986/000127
Authority: WO
Inventors: Kazuyuki Matsumoto; Toshiharu Hibino
Original assignee: Teijin Seiki Co., Ltd.
Priority date: 1985-03-15
Filing date: 1986-03-13
Publication date: 1986-09-25

Abstract

A geared motor comprising a housing (1, 41), an output shaft (3, 43) born on the housing in a rotatably journaled manner, a magnetic drive member (6, 26, 36) which is engaged with the output shaft to transmit rotational force and which is supported by the housing so as to move freely in a plane perpendicular to the axial direction, and an exciting member (11, 28, 48) which surrounds the drive member concentrically with the output shaft and of which the inner peripheral surface opposed to the outer peripheral surface thereof is fed with an exciting current. A rotating magnetic field is applied to the exciting member to cause the drive member to undergo planetary motion continuously around the output shaft by its rotational attractive force, and the speed is reduced at a reduction ratio that corresponds to the numbers of inner teeth and outer teeth. Namely, the motor is small in size, light in weight, and produces rotational force of a low speed and large torque.

Description

Description Geared motor

Technical field

The present invention relates to a geared motor, particularly to a geared motor suitable for robot control, servo control, and the like.

Background technology

Geared motors are used in robots as low-speed, high-torque motors. As a conventional geared motor, for example, one described in Japanese Patent Application Laid-Open No. 57-208388 is known. In this conventional geared motor, a first internal gear is provided on the inner periphery of a steel that generates a rotating magnetic field, and a planetary gear that performs planetary motion is combined with the first internal gear to output a planetary gear. Magnetize in the 轴 direction, associate a second internal gear, different from the pitch of the first internal gear, with the output shaft, and engage the planetary gear with the second internal gear so as to perform planetary motion. Thus, the output shaft is rotated by rotating the second internal gear by the westward rotation of the planetary gear. That is, when a rotating magnetic field is generated in the yoke, the planetary gears perform planetary motion with respect to the first internal gear fixed to the yoke, so that the planetary gears also perform planetary motion with respect to the second internal gear. do. The pitch of the first internal gear is different from that of the second internal gear. Therefore, when the planetary gear planetarily moves with respect to the first internal gear, the planetary gear moves with the second internal gear and at the same time as the second internal gear. Press the side of the gear to rotate the second internal gear. As a result, the output shaft rotates, and the rotation of the output shaft is reduced according to the number of teeth of the first internal gear and the second internal gear.

However, in such a conventional geared motor, the first internal gear and the second internal gear are arranged in parallel in the output shaft direction, and the second internal gear associated with the output shaft is automatically rotated. However, since the geared motor must be supported in place, the geared motor has the disadvantage that it becomes thicker and larger in the direction of the output shaft of the gear.

Therefore, the present invention has been made to solve the above-mentioned drawbacks of the conventional example, and has as its object to obtain a thin, small, and lightweight geared motor. -Disclosure of the invention

According to the first invention of the present application, which has been made to achieve the above object, according to the present invention, there are provided a housing, and an output shaft which is rotatably supported on the housing and is provided with external teeth along a shaft circumference. Internal teeth having a larger pitch circle diameter and a larger number of teeth than the external teeth are provided along the inner peripheral surface, and have predetermined eccentricity in a plane perpendicular to the axial center direction of the output shaft. A magnetic driving member supported on the housing so as to be swingable by an amount, and a magnetic driving member supported on the housing and surrounding an outer peripheral surface of the driving member so as to surround the driving member from a peripheral direction on a concentric circle of the output shaft. An exciting member to which an exciting current is supplied along a facing inner peripheral surface, and a geared motor characterized by comprising:

According to a second aspect of the present invention, an output shaft rotatably supported by the housing is provided. A magnetic driving member which is supported at the end of the output shaft and can swing by a predetermined amount of eccentricity in a plane perpendicular to the axial direction and has external teeth along a circumference close to the outer periphery Internal teeth having a larger pitch circle diameter and a larger number of teeth than the external teeth are provided along the inner periphery so as to be fixed to the housing on the concentric circle of the output shaft and to fit with the external teeth. An exciting member fixed to the housing on a concentric circle of the output shaft, and having an inner peripheral diameter larger than the outer peripheral diameter of the driving member, to which an exciting current is supplied along the inner periphery. And a geared motor characterized by having the following configuration.

According to the geared motor having the configuration according to the first and second aspects of the invention. Since the drive and transmission members are combined in a plane perpendicular to the axis of the output shaft, the output shaft A thin, compact and lightweight geared motor can be obtained in the axial direction.

Further, according to the geared motor having the configuration according to the second aspect of the present invention, since a rotational driving force can be obtained at a position close to the axis of the output shaft, it is possible to obtain a smaller and lighter geared motor even in a direction perpendicular to the axis. it can.

Brief explanation of drawings

FIG. 1 is a side sectional view of a geared motor according to a first embodiment of the first invention of the present application,

FIG. 2 is a cross-sectional view taken along the line Π-II of FIG. 1,

FIG. 3 is a schematic view of a main part of the crank shaft (7) used in the first embodiment.

FIG. 4 is a side sectional view of a geared motor according to a second embodiment of the first invention of the present application, FIG. 5 is a front sectional view taken along the line VV of FIG.

FIG. 6 is a side sectional view of a geared motor according to an embodiment of the second invention of the present application,

Figure 7 is a sixth diagram right half - front sectional view decor section along Upsilon zeta wire, - Y, a section along the line, the six-view Y ₂ left half

FIG. 8 is a schematic view of a main part of the crank shaft (45) used in the above embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a geared motor according to a first embodiment of the first invention of the present application will be described with reference to FIG. 1 to FIG.

The housing 1 supports the output shaft 3 by itself through bearings 2A and 2B. A pair of gears 4 having external teeth 4 a is fixed on the output shaft 3 so as to face each other via a spacer 5. The tooth profile of the external tooth 4a is an arc-shaped tooth profile (a trochoid tooth profile). The outer teeth 4 a of each gear 4 are arranged so that two disk-shaped drive disks 6, which are formed by forming inner teeth 6 a corresponding to the outer teeth 4 a on the inner periphery, also face each other. Has been established. The drive disk 6 has the whole or at least the outer peripheral surface formed of a magnetic material.

The number of the external teeth 4 a of each gear 4 is, for example, 39, and the number of the internal teeth 6 a of the drive disk 6 corresponding to this is 40, that is, the number of the internal teeth 6 a is increased by one. a is formed in a pin shape, and the pitch circle diameter is larger than the pitch circle diameter of the external teeth 4a. The internal teeth 6a and the external teeth 4a theoretically meet with the total number of teeth, but actually have a gap due to processing tolerances, so that they are in a relationship where about half of them are combined. Therefore, the pamper rate is Since it is high, a large torque can be transmitted, and the backlash is averaged and reduced.

The output shaft 3 and each of the two drive disks 6, 6 are supported on the inner wall of the housing 1 by three crank shafts 7 as disk support members at, for example, three equal positions in the circumferential direction. It is in the shape. The structure of the crank shaft 7 is step-formed as shown in FIG. 3, and is supported on the drive discs 6, 6 with respect to the center axis £ of the shaft supports 7a, 7a at both ends. The offset directions of the parts 7b and 7b are 180 ° out of phase with each other, forming a shape like a vehicle crank shaft.

The crank shaft 7 is rotatably supported on the housing 1 by roller bearings 8 at shaft support portions 7a, 7a at both ends thereof. Thus, the drive disk 6 is relatively rotatably supported. Therefore, the two drive disks 6, 6 can be rotated with a phase shift of 180 ° and the amount of offset corresponding to the offset amount can be caused by the rotation of the crank shaft 7, and It is a mechanism that carries out planetary motion about the output shaft 3.

Here, the structure of the housing 1 can be divided into right and left as shown in FIG. 1, and is connected by a bolt 10 inserted into a fastening hole 1a protruded from the right half. FIG. 2 shows a state in which a part of the housing 1 and the bolt 10 can be seen from each of the windows 6 opened at three positions in the circumferential direction by dividing the drive disk 6 in the circumferential direction. ing. Next, inside the housing 1, two disk-shaped exciting members (hereinafter simply referred to as yoke) 11, corresponding to the two drive disks 6, 6, are included so as to cover them from the outer peripheral direction. 11 is fixed to the housing 1 via the spacer 12.

Configuration of the yoke 1 1, radially to the circumferential direction, Coil le d ~ C _{1 6} is a sixteen conductor bundles in Example is incorporated at regular intervals. These coils C _t to C ₁₆ are connected by a circuit from a power source (not shown) so that an exciting current is supplied in order in a counterclockwise direction, for example. However, in the case of the embodiment, the remaining half of the coil excluding the coils in which the inner teeth 6a and the outer teeth 4a are deepest and shallowest (the state shown in Fig. 2) In Fig. 2, when an exciting current is applied to the coils C t to C ₇ ) and the state is closed, the other half of the other coils (coils C ₉ to C _{15 in} Fig. 2) ) Is set to the 0FF state. In this way, as shown in FIG. 2, seven magnet poles composed of N and S poles are formed along the inner peripheral surface of the yoke 11 by the excitation current. It is designed.

The inner diameter of the yoke 11 in which the N and S magnetic poles are alternately formed is twice as large as the outer diameter of the drive disk 6 by twice the offset amount described above; Thus, the drive disk 6 can swing within the yoke 11.

A multi-phase excitation method that forms a so-called rotating magnetic field by forming several N and S magnetic poles in a radial pattern is known in the book, “Theory and Application of Step Motors” (published by Jikkyo Shuppan Co., Ltd.). Therefore, description of the electric circuit and the like in the case of the embodiment is omitted. Although the drive disk 6 has been described as having a pair of two disks, this is preferable because of the operation and operation described later. The geared motor according to the invention can be obtained.

Further, when the geared motor of this embodiment is used as a servomotor, one of the shaft supports 7a of the crankshaft 7 is made to protrude out of the housing 1, and the rotation of the shaft shaft is fed back. It is preferable to provide a detector such as a encoder at the protruding portion, which is used as a lock signal. Since the rotation speed of crank shaft 7 is 39 times the rotation speed of output shaft 3, if the same high resolution is to be obtained, the detector attached to crank shaft 7 will have output shaft 3 This is because it is more accurate and inexpensive than that required.

When the geared motor of this embodiment is used as a motor with a brake, at least one crank shaft 7 and preferably one shaft support 7 of each crank shaft 7 is used. It is preferable to make a protrude out of the housing 1 and install a mechanical brake on the protruding portion. This is because only a small braking torque is required.

In addition, as in the case of an epicycle motor (trademark), for example, a three-phase power supply is connected to the coil of the magnetic pole through a rectifier to make the swinging motion of the main disc 6 oscillate. A method in which a magnetomotive force is generated in half of the area may be adopted.

Next, the operation and action of the embodiment will be described with reference to an example in which the output # 3 is rotated in the clockwise direction.

The state shown in Fig. 2, that is, the outer teeth 4a and the inner teeth 6a at the top are In most deeply嚙合state, (in FIG. 1, the left side of the yoke 11) one of the yokes 11 Coil le C in, allowed energizing the exciting current to ~ C _7, the other yoke 11 (in FIG. 1, right The coil groups C ₉ to C _15, which correspond to half of the yoke ii) in the above-mentioned sense, are simultaneously set to the 0N state.

Then, act as a suction force to Ka勳disk 6 force (indicated by arrows in FIG. 2) is the one of the magnetic force generated by co I Honoré ~ c ₇ of one of the yokes 11. The other yoke 11 side of the Coil le 11 C, the resultant force of the magnetic force generated by ~ C ₁₅ (indicated by arrow F ₂ in FIG. 2) acts as a suction force to the other of Ka勖disk 6. Suction force F,. F decomposition component caries Chi driving disk 6 _2, 6 central point A of, A (above the center of the output shaft 3 Ofuse Tsu preparative amounts apart points) to pass Ingredient f! F2 (shown in Fig. 2), it can be considered that a counterclockwise torque acts on disks 6 and 6. As a result, the drive disks 6, 6 swing (revolve) counterclockwise, and the output shaft 3 rotates clockwise due to the swing reaction force.

That is, if the coil group to be energized is on one yoke 11 side,

_{_{~ C 7, C 2 ~ C}} 8, C 3 and ~ C _9, an alien other yoke 11 side C ₉ ~ C _15,. ! . ~ 〇, old man ~. , A rotating magnetic field of the counterclockwise occurs due and sequentially switching this rotation the suction force generated by the rotation force F, the Mukurodo Day disk Ri by the F ₂ 6, 6 are Ren'nyo swing, i.e. the output shaft 3 The oscillating motion (revolution) is continuously performed in the direction of clockwise around the circumference. Therefore, the output shaft 3 rotates in the clockwise direction. Since the number of teeth of the outer teeth 4a and the inner teeth 6a is 39, 40, and the number of teeth is 1, there is a difference of 1 between them. 1 turn I do. That is, in the geared motor of this embodiment, the reduction ratio is set as 1 Z39. In addition, since the pair of two supporting disks 6, 6 perform the above-described swing with a phase shift of 180 °, the effect of canceling out the shake due to the swing of each person is obtained. be able to. It is needless to say that a desired reduction ratio can be obtained by arbitrarily setting the ratio of the number of teeth of the outer teeth 4a and the number of teeth of the inner teeth 6a. 2 Example will be described with reference to FIG. 4 and FIG. In the description of the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, the drive disk 26 is a disk-shaped two drive member, and has a pin-shaped internal tooth 6 a ( 26 a) and outer teeth 26 b on the outer peripheral surface. The two building disks 26 are arranged to face each other via the spacer 5, and are interposed between the spacer 5 and the housing 1, respectively. The moving disk 26 has its entire surface or at least the outer peripheral surface formed of a magnetic material.

Inside the housing 1, two disk-shaped exciting members (hereinafter simply referred to as yokes) corresponding to the two drive disks 26, 26 from the outer peripheral direction thereof are provided. The configuration of the yoke 28 in which 28 (11) is fixed to the housing through the spacer 12 is equivalent to 11 in the second embodiment. , CC are the same as in the first embodiment, and operate in the same manner. The inner periphery of the yoke 28 has pin-shaped internal teeth 28a corresponding to the external teeth 26b of the drive disk 26, and the pitch circle of the internal teeth 28a is It is larger than the pitch circle of the external teeth 26b. The material of the bottle forming the internal teeth 28a is a non-magnetic material. The external tooth 26b has an arc-shaped tooth shape, similar to the external tooth 4a.

In addition, the number of teeth of the internal teeth 28a is, for example, 22, and the number of teeth of the external teeth 26b of the drive disk 26 corresponding thereto is reduced by one to 21. Therefore, the driving disk 26 is supported by the external teeth 26 b and the internal teeth 28 a so as to be able to revolve with respect to the output power 3, and the external teeth 26 b and the internal teeth 28 a constitute a support means 29. I have. When the driving disk 26 revolves, it rotates due to the difference in the number of teeth between the internal teeth 28a and the external teeth 26b. In other words, the drive disk 26 revolves once by one-half of one revolution. By changing the number of teeth of the outer teeth 26b and the inner teeth 28a and the number of the outer teeth 4a and the inner teeth 26a, the reduction ratio can be adjusted over a wide range and finely. The engagement between the internal teeth 28a and the external teeth 26b and the engagement between the internal teeth 6a and the external teeth 4a have a high engagement ratio similarly to the first embodiment, and can transmit a large torque. Further, the drive disk 26 does not need to be supported by the crank shaft 7 as in the first embodiment, and the outer diameter of the drive disks 2 and 6 can be reduced by that much, so that The size can be reduced in the direction perpendicular to the center of the gear motor.

The axes Α of the two drive disks 26, 26 revolve around the axis P of the output shaft 3, respectively, but as shown in Fig. 5, the revolutions are out of phase with each other by an angle of 180 '. In addition, the shaft center A has an offset amount z from the shaft center P. Therefore, the drive disk 26 is configured to perform a planetary swing corresponding to the offset amount ₂ . The configuration other than the above is the same as that of the first embodiment.

Next, the operation of the second embodiment will be described. When current is supplied to the coil groups of the two yokes 28 (11) and 28 (11), respectively, and the coil groups are sequentially switched, the yokes 28 and 28 are counterclockwise. A rotating magnetic field is generated, and the moving disks 26, 26 are rotated around the output shaft 3 in a counterclockwise direction by the rotational attraction forces F 1, F ₂ due to the face-turning magnetic force (revolution). I do. Therefore, the outer teeth 26b of the drive disks 26, 26 engage with the inner teeth 28a and rotate continuously (clockwise) in the clockwise direction. Then, since the number of teeth of the outer teeth 26 b and the inner teeth 28 a is 21 and 22 and the number of teeth is 1, when the drive disk 26 repeats swinging 21 times, the driving disk 26 becomes One rotation. In addition, since the number of internal teeth 6 a of the main disk 26 and the number of external teeth 4 a of the gear 4 are 14, 13 and the number of teeth is 1, the output is obtained when the drive disk 26 swings 14 times. The shaft makes one revolution. That is, the reduction ratio of this geared motor is 1Z21.113 ^ 1 18. That is, a wide range of deceleration can be achieved by changing and combining these reduction ratios.

Hereinafter, a geared motor according to a second embodiment of the present invention will be described with reference to FIGS. 6 to 8. FIG.

An output shaft 43 is rotatably supported by the housing 41 via bearings 42A and 42B. The output shaft 43 has a dividable structure including a main body shaft 43A and a stop shaft 43B, and these two shafts 43A and 43B are bolted at, for example, three equally divided positions in the circumferential direction. It is connected by G44.

In addition, three crank shafts 45 are also provided on the joint surfaces of the two shafts 43A and 43B at each of three equally divided positions in the circumferential direction via roller bearings 45d. It is rotatably supported by 43 A and 43 B. The shape of the crank shaft 54 is stepped and formed as shown in FIG. 8, and the shaft supporting portions 45a, 45a, which are respectively supported on both shafts 43A and 43B of the output shaft 43, are formed. With respect to the rotation center axis £-& of 45a, two central portions are formed as carrying portions 45b and 45b which are respectively eccentric by the dimension of the signal ₃ due to a phase shift of 180 '. That is, rotation center axis of the bearing unit 45 b, 45 b is represented in the figure £ ₄ one "line.

Next, in the bearing portions 45b, 45b of the crank shaft 45, two disk-shaped driving disks 46, 46, which are two driving members, are passed through roller bearings 47 to the bearing portions 45b, 45b. It is carried so that it can rotate relative to 45b. That is, the drive disks 46, 46 are 180 relative to each other. With the phase shift of, the amount of eccentricity (offset) in the supporting parts 46b and 45b; ₃ works like a crank for a vehicle, and can rotate in the same direction as the output shaft 43 and is offset. The swing by the movement of the amount ₃ is enabled in the plane perpendicular to the axis of the output shaft 43.

Further, each of the drive disks 46 is formed with a step and serves as a gear member having external teeth 46a formed along the outer periphery of the step (see FIG. 1). The tooth shape of the external teeth 46a is an arc-shaped tooth shape, like the external teeth 4a and 26a described above. The entire drive disk 46 or at least the periphery of the external teeth 46a is made of a magnetic material.

On the other hand, the internal teeth 48a corresponding to these external teeth 46a, 46a of the driving disks 46, 46 are formed along the inner peripheral surface, and the guide members of the two drive disks 46, 46 are used. A guide panel 48 with a wheel stub is fixed to the housing 41 on the concentric circle of the output shaft 43. In the case of the embodiment, the number of internal teeth 48a Is one more than that of the external teeth 46a, with 39 external teeth 46 and 40 internal teeth 48a. The inner teeth 48a are formed in a pin shape, and the pitch circle diameter is larger than that of the outer teeth 46a. The internal teeth 48a and the external teeth 46a theoretically meet with the total number of teeth, but actually have a gap due to processing tolerances, and therefore have a relationship where about half of them are combined. Therefore, since the engagement ratio is high, a large torque can be transmitted, and the backlash is averaged and reduced.

Exciting members (hereinafter, simply referred to as yoke) 49, 49 on the disk correspond to the outer peripheral surfaces of the two drive disks 46, 46, respectively. Fixed.

Configuration of each yoke 49 has its radially circumferentially Coil le C _{4 1} ~ C _{5 &} a sixteen conductor bundles in Example are incorporated equidistantly. This Rerako b le C 4 i~ C _{5 6} is in the forward direction, for example clockwise迺Ri, the exciting current is connected in the circuit from the power source (not shown) to be energized. However, in the case of the embodiment, the remaining half of the coil excluding the one in which the inner teeth 48a and the outer teeth 46a are in the deepest and shallow directions (in the state shown in FIG. 7). by energizing the exciting current to Koi Le _{_{C 4 2 ~ C 4 8)}} 0 when the N state, co in Coil le (second view of the other remaining half Lee le C ₄ .~ C _{5 6} ) Is set to 0FF state. In this way, as shown in Fig. 2, the excitation current is applied to form seven convenient magnetic poles consisting of N and S magnetic poles along the inner peripheral surface of the fork 49. ing.

The inner diameter of the yoke 49 in which the S magnetic poles are alternately formed is twice the offset amount described above than the outer diameter of the drive disk 46; The drive disk 46 is large only by the dimension, so that the drive disk 46 can be swung in the yoke 49 via a guide panel 48 integrated with the yoke 49.

The multi-phase excitation method in which several NS magnetic poles are formed radially to form a so-called rotating magnetic field is known in books such as "Theory and Application of Step Motors (Jikkyo Shuppan Co., Ltd.)" Description of the electric circuit and the like in the case of the embodiment is omitted.

Although the drive disk 46 has been described as having a configuration in which two drive disks are paired, this is preferable because of the operation and operation described later, and a configuration using one drive disk 46 is also preferable. The geared motor of the present invention can be obtained. Further, the rotational attraction force for causing the drive disk 46 to make a rocking motion is generated by connecting a three-phase power source to the coil of the magnetic pole through a rectifier, for example, as in an epicycle motor (trademark). A method that generates a magnetomotive force in half of the time may be used.

Next, the operation and action of the embodiment will be described with reference to an example in which the output 轴 3 is rotated in the clockwise direction.

In the state shown in FIG. 7, that is, in a state where the inner teeth 48a and the outer teeth 46a at the top are most deeply combined, the coil C _{4 is} placed on one yoke 49 (the right yoke 49 in FIG. 6). ₂ C _{4 8} to allowed energizing the exciting current, the other yoke 49 (first in FIG. 6, the left side of the yoke 49) above meaning in the Coil Le group corresponding to half C ₅ C _{5 6} also oN energized simultaneously state to result, act as a suction force to one ® one 'click 49 side of Coil Le CC ₄ resultant force of the magnetic force caused by the ₈ (Figure 7 arrow F ₅ in the display) is the one of the drive disk 46 Do. The coil on the other yoke 49 side C _5. Resultant force of the magnetic force (indicated by arrow F ₆ in FIG. 7) acts as a suction force to the drive disk 46 of the other hand caused by. Attraction force F _5, the center point A of the cracking component sac Chidi disk 46, 46 F 6, A; component through (heart the offset amount in the output shaft 3 3 apart points) ί 5, f

By 6 (shown in Fig. 7), it can be considered that the torque in the clockwise direction acts on the disks 46 and 46. As a result, the disks 46, 46 swing (revolve) in the clockwise direction and rotate in the clockwise direction. Since the rotation of the disks 46-46 is transmitted to the output shaft 43 via the crank shaft 45, the output shaft 43 rotates clockwise.

That is, in a co-I le group to energize the one of the yokes 49 and _{C 42 ~ C 4 8. C} 43 ~ C 49, C 44 ~ C 50, be in the other yoke 49 side. The C _5. _{_{~ C 56, C 5 t ~}} C 4, C 5 2~ C 4 2 sequentially particular resulting rotating magnetic field clockwise is than switched with each MukuroTsutomu disk by the rotating suction 'force F _3, F 6 by the rotation force 46, 46 perform continuous rocking, that is, continuous rocking motion (revolution) around the output shaft 43 in the clockwise direction. Therefore, the output No. 43 continuously rotates clockwise through the crank shaft 45. Since the number of teeth of the outer teeth 46a and the number of teeth of the inner teeth 48a are 39 and 40, and the number of teeth is 1, the output shaft 43 is turned at the time when the drive disk 46 oscillates 39 times. One rotation. That is, in the geared motor of this embodiment, the gear ratio is set to 1/39. In addition, since the pair of two movable disks 46, 46 perform the above-mentioned swing with a phase shift of 180 ', the effect of canceling the shift caused by the swing of each other can be obtained. I like it. Furthermore, a desired reduction ratio can be obtained by arbitrarily setting the ratio of the number of the outer teeth 46a and the number of the inner teeth 48a. Needless to say.

Industrial applicability

The geared motor of the present invention has been reduced in size and weight, for example, for various robots for industrial, medical, nuclear, etc., which use a low-speed, high-torque motor as a drive source, machine tools, servo control for automatic control, etc. It can be used suitably when it does.

Claims

The scope of the claims

1. a housing (1); an output shaft (3) rotatably supported by the housing and provided with external teeth (4a) along the outer periphery; Also, the internal teeth (6a) having a large pitch circle diameter and a large number of teeth are provided along the inner peripheral surface, and a predetermined amount of eccentricity (,,,) is set in a plane perpendicular to the axis of the output shaft. ₍₂ ) a magnetic drive member (6, 26) supported on the housing so as to be swingable by the housing; and a magnetic drive member (6, 26) supported on the housing so as to surround the drive member from the outer peripheral direction on a concentric circle of the output shaft; An excitation member (11, 28) to which an excitation current is supplied along an inner peripheral surface facing the outer peripheral surface of the driving member.

2. A housing (41) ', an output shaft rotatably supported by the housing' (43), and a predetermined eccentricity in a plane supported at the end of the output shaft and perpendicular to the axial center direction. the amount the magnetic drive member having external teeth (46 a) along a circumference close to the can and the outer periphery be swung by (scan ₃₎

And (46) an internal tooth having a larger pitch circle diameter and a larger number of teeth than the external teeth so as to be fixed to the housing on the concentric circle of the output shaft so as to fit with the external teeth. a) a guide member provided along the inner circumference

(48) an exciting member fixed to the housing on a concentric circle of the output shaft, having an inner peripheral diameter larger than the outer peripheral diameter of the driving member, and supplying an exciting current along the inner periphery; 49) A geared motor characterized by comprising: