JP4313683B2 - Geared motor - Google Patents

Description

  The present invention relates to a geared motor that is used in a state where a motor and a speed reducer are connected.

  Many factories in recent years are designed so that only necessary machines in necessary places can be operated when necessary due to efficiency problems.

  In factories of such a system, geared motors are often used as drive means for each machine. In the geared motor, the motor and the speed reducer are connected in advance, and the output shaft adjusted to a predetermined rotation speed or output torque can be rotated by itself. Moreover, since only a predetermined machine can be efficiently operated simply by turning the geared motor on and off, handling is easy.

  In general, a motor shaft of a geared motor and an input shaft of a reduction gear are connected by a joint structure through a key or the like, or a structure in which a dedicated shaft joint (coupling) or the like is interposed (for example, see Patent Document 1).

  For geared motors that are expected to be mass-produced, a pinion or the like corresponding to the input shaft of the reducer is integrally formed at the tip of the motor shaft, and the motor shaft directly serves as the input shaft of the reducer. Is also known.

Japanese Patent Laid-Open No. 10-299841

  The joint structure that uses a key or the like to connect the motor shaft and the input shaft has a problem that stress tends to concentrate only at one location in the circumferential direction where the key exists.

  In addition, the structure using a dedicated shaft coupling is versatile in that even if there is some variation in the specifications of the motor and reduction gear, both can be connected. In addition, the axial length tends to be long.

  The structure in which the motor shaft and the input shaft are integrated from the beginning does not cause a problem such as an increase in the number of parts, but the motor shaft is a dedicated product in the geared motor and is not versatile.

  The present invention has been made in view of such a conventional problem, and the motor shaft and the input shaft can be coupled in a low-cost and compact manner without increasing the number of components. It is an object of the present invention to provide a geared motor capable of preventing the occurrence of a problem that stress is concentrated only at one place.

The present invention relates to a geared motor that is used in a state where a motor and a speed reducer are connected, wherein the speed reducer uses a planetary roller mechanism that uses a sun roller as an input shaft of the speed reducer, and the motor shaft of the motor the outer diameter of the distal end surface and the tip surface of the input shaft of the reduction gear, Rutotomoni are opposed in a power transmission inside the inner race of a single bearing, within the inner ring of the bearing, the input shaft of the reduction gear Is set smaller than the inner diameter of the inner ring of the bearing, thereby solving the above-mentioned problems.

  In the present invention, a structure is adopted in which the front end surface of the motor shaft and the front end surface of the input shaft are opposed (matched) inside the inner ring of a single bearing.

  Here, the term “tip surface” of the motor shaft or the input shaft is interpreted in a broad sense and includes a case where irregularities or the like are formed on each surface to enable power transmission. That is, it does not necessarily have to be a plane.

According to the present invention, since the bearing has a function similar to a so-called coupling, there is no increase in the number of parts, and there is no possibility of an increase in size, an increase in weight, or the like. Unlike the key connection, the stress is not concentrated only at one specific place in the circumferential direction. Further, by giving the input shaft of the speed reducer self-alignment, it is possible to cancel the effects of shaft runout and assembly errors.

  In the present invention, the shape and the like of each front end surface for enabling power transmission are not particularly limited (described later).

  The motor shaft and speed reducer of the motor do not increase the number of parts, increase the size, increase the weight, etc., and do not cause the problem of stress concentration at a specific location in the circumferential direction. The input shaft can be easily and inexpensively connected.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  A geared motor (motor-integrated speed reducer) GM1 shown in FIGS. 1 to 5 is obtained by connecting a motor M1 and a speed reducer G1 using a joint structure to which the present embodiment is applied.

  FIG. 1 is an overall longitudinal sectional view of the geared motor GM1, and FIG. 2 is an exploded sectional view of an essential part thereof.

  The motor cover 12 of the motor M1 also serves as a cover on the motor M1 side of the reduction gear G1, and the tip 18A of the motor shaft 18 of the motor M1 faces the cylindrical portion 12A continuously formed on the motor cover 12. The motor shaft 18 is supported by a pair of bearings 17 and 19. Among these, the bearing 19 on the reduction gear G1 side corresponds to a bearing related to the present embodiment.

  A front end portion 18A of the sun roller 22 (input shaft of the speed reducer G1) of the simple planetary roller mechanism 20 constituting the front stage of the speed reducer G1 faces the front end portion 18A of the motor shaft 18.

  As shown in FIG. 5, in this embodiment, a linear recess (groove) 18 </ b> A <b> 1 is formed on the tip surface 18 </ b> A of the motor shaft 18, while this recess is formed on the tip surface 22 </ b> A of the sun roller 22. A linear convex portion (tenon) 22A1 that fits into 18A1 is formed. That is, the front end surface 18A of the motor shaft 18 and the front end surface 22A of the sun roller 22 that is the input shaft are opposed to each other and connected by an uneven structure that fits inside the inner ring 19A of the bearing 19. The concave portion 18A1 and the convex portion 22A1 are surrounded by the inner ring 19A of the bearing 19 on the speed reducer G1 side of the motor M1 so that the “ring” can be fitted, and the movement in the radial direction is restricted.

  Referring also to FIG. 3, the simple planetary roller mechanism 20 includes a sun roller 22, a planetary roller (planetary member) 24 that circumscribes the sun roller 22 (indirect contact via oil), and the planetary roller 24. And a ring roller (ring member) 26 that is inscribed therein, and a revolution component of a carrier pin 27 that supports the planetary roller 24 is output via a carrier (output shaft of the simple planetary roller mechanism 20). Has been.

  The sun roller 22 is supported by a bearing 19 on the reduction gear G1 side of the motor shaft 18 and four planetary rollers 24 arranged on the outer periphery of the sun roller 22. That is, there is no dedicated bearing for supporting the sun roller 22 that is the input shaft of the reduction gear G1 on the reduction gear G1 side.

  In this embodiment, the outer diameter of the sun roller 22 and the inner diameter of the inner ring 19A of the bearing 19 will be supplementarily explained. The outer diameter of the inner ring 19A of the bearing 19 of the sun roller 22 is slightly larger than the inner diameter of the inner ring 19A. Designed small. This is because in the case of the planetary roller mechanism 20, the axial center of the sun roller 22 is determined by the ring roller 26 and the planetary roller 24. That is, the sun roller 22 needs to have self-alignment in order to cancel the influence of the shaft shake and the assembly error.

  However, the difference is not large, and there is an effect that the sun roller 22 is largely shaken for some reason by pressing the inner ring 19A of the bearing 19. Therefore, in this sense, it can be said that the sun roller 22 is also supported by the bearing 19.

  When the speed reduction mechanism in the previous stage is, for example, a simple planetary gear mechanism, since self-alignment can be performed between the sun gear and the planetary gear, the sun gear is literally “supported” by the inner ring 19A of the bearing 19. You may do it.

  On the other hand, the planetary gear mechanism 50 at the rear stage is a swinging intermeshing planetary gear mechanism, as shown in FIG. 4, and an input shaft 51 (=) to which the power from the simple planetary roller mechanism 20 at the front stage is input. A carrier 28), an external gear 56 incorporated so as to be able to eccentrically swing with respect to the input shaft 51, an internal gear 58 in which the external gear 56 is in mesh with the internal gear 58, and the internal gear 58. The output body (rotating wheel) 62 is provided.

  The external gear 56 has a tooth profile based on a trochoid curve, and the internal teeth of the internal gear 58 are constituted by roller-shaped pins 58A.

  In addition, the code | symbol 30 in FIG. 1, FIG. 2 is an electromagnetic clutch.

  The specific configurations of the rear stage planetary gear mechanism 50, the electromagnetic clutch 30, and the like are not particularly related to the present invention, and thus detailed description thereof is omitted here.

  Next, the operation of the geared motor GM1, particularly the joint portion between the motor M1 and the reduction gear G1, will be described.

  When the motor shaft 18 of the motor M1 rotates, the recess 18A1 of the tip surface 18A of the motor shaft 18 also rotates. As a result, the convex portion 22A1 of the tip end surface 22A of the sun roller (input shaft) 22 on the speed reducer G1 side fitted to the concave portion 18A1 rotates, and the rotation of the motor shaft 18 is transmitted to the sun roller 22 side. The Since the concave portions 18A1 and the convex portions 22A1 of the both end surfaces 18A and 22A are surrounded by the inner ring 19A of the bearing 19, the fitting structure does not come off. The inner ring 19 </ b> A of the bearing 19 rotates integrally with the motor shaft 18.

  One end of the sun roller 22 is supported by four planetary rollers 24.

  FIG. 6 shows an example of a variation of the embodiment of the present invention.

  FIG. 6A shows a fitting structure of the tip surface 118A of the motor shaft 118 and the tip surface 122A of the sun roller (input shaft) 122, and a + -shaped recess 118A1 and a + -shaped protrusion that fits into the recess 118A1. An example in which the portion 122A1 is opposed to and coupled to the inner side of the inner ring 119A of the bearing 119 is shown. As illustrated in FIG. 6A, the concave portion 118A1 and the convex portion 122A1 do not necessarily correspond completely geometrically. Even if a slight difference in shape occurs between the two 118A1 and 122A1 for reasons of processing technology, there is no problem in practical use.

  As an example of application, although not shown in the figure, for example, an example in which concave portions formed at intervals of 60 degrees and convex portions corresponding to the concave portions are opposed to each other can be considered. This type of concave-convex fitting structure has an advantage that stress concentration is further reduced as compared with the negative-shaped concave portion 18A1 and convex portion 22A1 according to the embodiment.

  FIG. 6B shows a fitting structure of the tip surface 218A of the motor shaft 218 and the tip surface 222A of the sun roller 222. The example which opposes and connects inside the inner ring | wheel 219A of 219 is shown.

  On the other hand, in FIG. 6C, the simplest combination example is shown. That is, in this example, the front end surface 318A of the motor shaft 318 and the front end surface 322A of the sun roller 322 are simply opposed to each other inside the inner ring 319A of the bearing 319 so as to be press-fitted from both sides of the bearing 319. The tip surfaces 318A and 322A are not particularly formed with uneven shapes. However, if the handling torque is relatively small, this is often sufficiently practical. Such a structure is also included in the structure “the front end surface of the motor shaft and the front end surface of the input shaft are opposed to each other inside the inner ring of a single bearing so that power can be transmitted”.

  In addition, you may apply | coat an adhesive lightly to the inner side of a bearing, or a front end surface. Further, use of a member such as a key is not prohibited.

  Furthermore, in the above specific example, the formation of the concave portions and the convex portions may be reversed. In addition, when a technique such as mold production can be employed, for example, a recess formed based on a trochoid curve, a cycloid curve, or the like (for example, the tooth profile shape of the external gear 56 based on the trochoid curve shown in FIG. 4). It is good also as a structure which combined the recessed part which has a similar shape, and the convex part which has a shape corresponding to this. This type of “curved” continuous type fitting structure has the advantage that the stress concentration is particularly small.

  Thus, in the present invention, there is no particular limitation on the specific structure for facing the power transmission. Also, the type of motor and the type of speed reducer are not particularly limited to the above example.

  The present invention is applicable to all types of geared motors.

The longitudinal cross-sectional view which shows the whole structure of the geared motor to which the example of embodiment of this invention was applied 1 is an exploded view of the main part of FIG. Sectional view along line III-III in FIG. Sectional view along line IV-IV in FIG. 1 is an exploded perspective view of the joint portion of FIG. It is a disassembled perspective view of the joint part which shows the example of other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS M1 ... Motor G1 ... Reduction gear GM1 ... Geared motor 14 ... Casing 18 ... Motor shaft 19 ... Bearing 19A ... Inner ring 18A ... End face 18A1 ... Recess 20 ... Simple planetary roller mechanism 22 ... Sun roller (input shaft)
22A ... tip face 22A1 ... convex part 24 ... planetary roller 26 ... ring roller (ring member)
DESCRIPTION OF SYMBOLS 30 ... Electromagnetic clutch 50 ... Swing internal meshing type planetary gear mechanism 62 ... Output body

Claims (4)

In a geared motor used in a state where a motor and a reduction gear are connected,
The speed reducer uses a planetary roller mechanism in which the input shaft of the speed reducer is a sun roller,
A distal end surface of the input shaft of the front end surface and the reduction gear of the motor shaft of the motor, dissipate power transmittable opposing inside the inner race of a single bearing, within the inner ring of the bearing, the input of the speed reducer A geared motor , wherein an outer diameter of the shaft is set smaller than an inner diameter of an inner ring of the bearing . In claim 1,
The geared motor is characterized in that the front end surface of the motor shaft and the front end surface of the input shaft are opposed to and connected to each other by a concavo-convex structure that fits together. In claim 1 or 2,
The geared motor, wherein the bearing is a reduction gear side bearing of a motor shaft of the motor. In any one of Claims 1-3 ,
The geared motor, wherein the sun roller is supported by a planetary roller of the planetary roller mechanism.

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