JP2002181140A - Speed reduction gear with motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce motor noise with ease by restraining the running out of an input shaft 21 and a rotary shaft 19. SOLUTION: If a bearing for the rotary shaft 19 is eliminated by connecting the rotary shaft 19 of a drive motor 23 to the input shaft 21, a large load acts on the input shaft 21. However, since the input shaft 21 is rotatingly supported by an angular ball bearing 50 wherein there is little radial clearance, and the positional dimension of the point on which a bearing load acts becomes long by arranging the bearing 50 with the outer ring 50a mated at its back face, to enhance the rigidity of the bearing, and to restrain shaft running effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reduction gear with a motor, which is constructed by assembling a rotation shaft of a drive motor with an input shaft of the reduction gear while maintaining a coaxial relationship.

[0002]

2. Description of the Related Art As a conventional speed reducer with a motor, for example, one described in Japanese Patent Application Laid-Open No. Hei 5-44792 is known. This is constructed by assembling the rotation shaft of the drive motor with the input shaft of the reduction gear while maintaining the coaxial relationship. The input shaft of this reduction gear has both ends in the axial direction at the fixed portions ( The casing is rotatably supported via a pair of deep groove ball bearings, and the rotating shaft of the drive motor is also rotatably supported at both axial ends by bearings on fixed portions of the drive motor. And
The input shafts of these reduction gears and the rotation shafts of the drive motors are connected by couplings at ends that are close to each other.

However, in such a conventional reduction gear with a motor, both the input shaft of the reduction gear and the rotation shaft of the drive motor can be rotated via bearings on fixed portions of the reduction gear and the drive motor, respectively. Therefore, there is a problem that bearings are required for both sides, the overall axial length is increased, and the structure is complicated and expensive.

[0004] For this reason, the present applicant has filed Japanese Patent Application No. 2000-3.
No. 38592, both ends in the axial direction of an input shaft of a speed reducer are rotatably supported on fixed portions of the speed reducer via bearings, and a rotation shaft of a drive motor is connected to a drive motor of an input shaft of the speed reducer. A speed reducer with a motor has been proposed which is connected to an adjacent end portion, thereby omitting a bearing for supporting a rotating shaft of a drive motor.

[0005]

As a result, a larger load acts on the input shaft of the speed reducer than in the prior art. However, both ends of the input shaft in the axial direction are paired with a pair of deep groove balls as in the prior art. When the bearing is supported by the bearing, there is a problem that the input shaft and the rotating shaft largely shake during rotation due to the influence of the radial gap, thereby generating a large motor noise.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a motor-equipped reduction gear capable of easily reducing motor noise by suppressing shaft runout of an input shaft and a rotation shaft.

[0007]

SUMMARY OF THE INVENTION The purpose of the invention is as follows.
In a reduction gear with a motor configured by assembling the rotation axis of the drive motor to the input shaft of the reduction gear while maintaining the coaxial relationship, both axial ends of the input shaft of the reduction gear are fixed to the fixed part of the reduction gear, The outer ring is supported rotatably via a pair of angular ball bearings that are back-to-back,
Second, by using a rotary shaft of the drive motor coupled to an end of the input shaft of the speed reducer close to the drive motor, a tapered roller bearing having an outer ring back-to-back is used instead of the angular ball bearing. Can be achieved.

When the rotary shaft of the drive motor is connected to the input shaft of the speed reducer as described above, a large load acts on the input shaft of the speed reducer. For example, a deep groove ball bearing having a radial gap is used. When interposed between the input shaft and the fixed portion of the speed reducer, the input shaft and the rotating shaft may be largely shaken during rotation. However, according to the present invention, the angular ball bearing having almost no radial clearance, the conical Since the roller bearing is interposed between the input shaft and the fixed portion, the above-described shaft runout can be effectively suppressed. In addition, since the pair of angular ball bearings and tapered roller bearings are arranged with the outer ring being back-to-back, the location of the point of application of the bearing load (the extension of the contact line of the rolling element forming each bearing) And the shaft center line, ie, the distance between the intersections), the bearing stiffness, for example, the moment load capacity, is improved, whereby the aforementioned shaft runout is effectively suppressed, and the motor noise is effectively reduced. Reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1, 2 and 3, reference numeral 11 denotes a motored reduction gear used for hoisting an elevator. The motored reduction gear 11 has a fixed member 12 fixed to a fixed frame (not shown). Reference numeral 12 denotes a large-diameter disk-shaped large-diameter portion 13, a small-diameter disk-shaped small-diameter portion 14 continuous to one side of the large-diameter portion 13, and protrudes from one side of the small-diameter portion 14 toward one side. And a plurality of pillars 15. Here, the other end face of the large-diameter portion 13 is mostly flat except for the outer end in the radial direction.

Reference numeral 16 denotes a cylindrical case having a bottom as a fixing portion. The open end (one end) of the case 16 is fixed to the other side surface of the large-diameter portion 13.
A disc-shaped closed space 17 is formed between the two. Reference numeral 18 denotes a cylindrical coil fixed to the outer end of the case 16 in the radial direction.
A substantially disk-shaped rotating shaft 19 coaxial with the input shaft 21 of 20 is provided, and a plurality of permanent magnets 22 arranged along the coil 18 are fixed to a radially outer end of the rotating shaft 19. I have. The above-described case 16, the coil 18, the rotating shaft 19, and the permanent magnet 22 as a whole constitute a drive motor 23 juxtaposed to the speed reducer 20, here an electric motor.

Here, the inner end of the rotary shaft 19 in the radial direction is connected to the other end of the input shaft 21, that is, the end close to the drive motor 23 by a wedge member 24 so as to rotate integrally therewith. When the coil 18 is energized, a permanent magnet
The rotation 22 rotates around the axis, and this rotation is transmitted to the input shaft 21 through the rotation shaft 19 to drive and rotate the input shaft 21.

Numeral 26 denotes braking means housed inside the driving motor 23 in the radial direction. The braking means 26 applies a braking force to the rotating shaft 19 and the permanent magnet 22 which are the rotating parts of the driving motor 23. The braking means 26 has a ring-shaped fixing member 27 fixed to the case 16, and a plurality of guide screws 28a and 28b are screwed and fixed to the outer periphery of the fixing member 27.

Numerals 29a and 29b are a pair of arcuate shoes, which are arranged 180 degrees apart in the circumferential direction. Here, these shoes 29a and 29b are arranged on the outside of the fixing member 27 in the radial direction. The guide screws 28a and 28b are slidably inserted. As a result, these shoes 29a,
b is supported by the fixing member 27 via the guide screws 28a and 28b so as to be movable in the radial direction.

Reference numerals 30a and 30b denote a pair of arc-shaped plates which can contact the inner periphery of the fixing member 27.
b and the shoes 29a and 29b are connected to each other by a pair of connecting rods 31a and 31b penetrating the fixing member 27 in the radial direction. A pair of springs 32a, b are housed in the fixing member 27 so as to surround the connecting rods 31a, b, and these springs 32a, b apply a biasing force toward the outside in the radial direction to the shoes 29a, b. Then, these shoes 29a and 29b are connected to a rotating shaft 1 which is a rotating portion of the drive motor 23.
9. Pressing against the inner periphery of the permanent magnet 22, thereby applying a braking force to the rotating shaft 19 and the permanent magnet 22.

If the two braking members having the shoes 29a and 29b are pressed against the inner periphery of the rotating shaft 19 to apply the braking force, the driving motor
Since braking is performed at two points on 23 at the same time, the braking force is doubled, and even if one of them breaks down, braking can be performed on the other. Thus, the braking means 26, that is, one braking device has two braking actuation parts therein, in other words, two braking actuations for one electric signal.
Since the two mechanical operating portions operate, the safety is improved and the size of the motored reduction gear 11 can be reduced.

Reference numeral 33 denotes a portion between the springs 32a and the spring 32.
The electromagnet 33 is housed in the fixing member 27 between the b. When the electromagnet 33 is energized, the electromagnet 33 attracts the shoes 29a and 29b and moves them radially inward against the springs 32a and 32b.
As a result, the shoes 29a and 29b are separated from the inner periphery of the rotating shaft 19, and the rotating part of the drive motor 23 is released from braking.

The aforementioned fixing member 27, guide screw 28a,
The b, shoes 29a, b, arc plates 30a, b, connecting rods 31a, b, springs 32a, b, and electromagnet 33 constitute the drum type braking means 26 as a whole. By doing so, the rotating shaft 19 (usually a separate braking drum) to which a braking force is applied from the shoes 29a and 29b is driven by a drive motor.
It can be used in common with the 23 rotating parts, so that the speed reducer with motor 11 can have a simple structure and a small size.

Reference numerals 34a and 34b denote a pair of substantially radially extending release levers whose inner ends in the radial direction are rotatably supported by the fixing member 27 via pins 35a and 35b. The radial inner ends of the arc-shaped plates 30a, 30b
, And a wire (not shown) is connected to a radially outer end thereof.

When the braking of the drive motor 23 is manually released in the event of a failure in which the energization of the electromagnet 33 cannot be controlled, the wire is pulled to swing the release levers 34a and 34b upright. , Arcuate plates 30a, b, connecting rods 31a, b, shoe 29
a, b are moved radially inward integrally with the springs 32a, b. 36 is a cooling fin fixed to the outer periphery of the case 16.

As described above, the drive motor 23 and the braking means 26 are mounted on the other side of the speed reducer 20 in a coaxial relationship. The speed reducer 20 is a ring fixed to one side surface of the column 15. It has an end plate 37 in the shape of an arrow. The above-described fixing member 12 and end plate 37 as a whole constitute a carrier 38 as a fixing portion of the speed reducer 20. The carrier 38 is cantilevered only with the fixing member 12 fixed to the fixed frame, and is not double-sided, so that the motored reduction gear 11 can be downsized. Reference numeral 39 denotes a cylindrical rotatable internal gear that surrounds the small diameter portion 14, the column portion 15, and the end plate 37 from the outside in the radial direction.
Numeral 39 is rotatably supported by a carrier 38 via a pair of bearings 40 interposed between the inner periphery of both ends in the axial direction and the outer periphery of the small diameter portion 14 and the end plate 37.

A plurality of sheave grooves 41 extending continuously in the circumferential direction are formed on the outer periphery of the internal gear 39.
A main rope (not shown), to which an elevator car is connected at one end and a counterweight is connected to the other end, is wrapped around 41. As a result, the internal gear 39 is integrated with the sheave, but this eliminates the need to attach the sheave to the internal gear 39 and simplifies the structure of the motored reduction gear 11.

At the center of the internal gear 39 in the axial direction at the inner periphery thereof, a large number of internal teeth pins 42 constituting internal teeth are supported in a state where they are inserted by almost half. Extend and are equidistant in the circumferential direction. Reference numeral 43 denotes cylindrical roller followers having the same number as the internal teeth pins 42. The roller followers 43 are rotatably fitted to the outside of the axial center portion of the internal tooth pins 42.

Reference numeral 46 denotes a plurality of, here three, ring-shaped pinions disposed between the small-diameter portion 14 and the end plate 37 in the internal gear 39. The inner tooth pin is provided on the outer periphery of each pinion 46. The number of external teeth 47 slightly smaller than the number of 42 is formed. The external teeth 47 of these pinions 46 are connected to the internal tooth pins 42 of the internal gear 39.
Are meshed with each other via a roller follower 43, but the meshing state is 180 degrees out of phase with the adjacent pinion 46. Since the outer teeth 47 of the pinion 46 are meshed with the roller followers 43 of the rotatable internal tooth pins 42 in this manner,
The engagement between the internal tooth pins 42 and the external teeth 47 is in rolling contact, so that the frictional resistance is greatly reduced, whereby the transmission efficiency is improved and the rotational noise is reduced.

Reference numeral 50 denotes a pair of bearings interposed between the carrier 38 and the input shaft 21 loosely fitted to the center of the carrier 38. Each part is rotatably supported on both sides by a carrier 38, that is, a fixed part of the reduction gear 20. In addition, the input shaft 21 has three eccentric portions 51 eccentric by an equal distance from the rotation axis at the axial center portion between the bearings 50. Of these eccentric portions 51, the adjacent eccentric portions 51 are 180 degrees apart. Out of phase. Each of these eccentric portions 51 is inserted into the pinion 46 with a roller bearing 52 interposed therebetween.

As a result, when the input shaft 21 is driven and rotated by the drive motor 23, the eccentric portion 51 rotates eccentrically, and eccentrically rotates (revolves) with the adjacent pinions 46 shifted in phase by 180 degrees. At this time, the number of internal teeth pins 42 and external teeth
47, the rotation of the input shaft 21 is greatly reduced by the eccentric rotation of the pinion 46, and the internal gear 39 is rotated.
To rotate the internal gear 39 at a low speed and run the main rope.

Numeral 55 denotes crankshafts which are arranged between the column portions 15 in the circumferential direction and are the same in number as the column portions 15. Both ends of the crankshaft 55 in the axial direction are bearings 56 on the small diameter portion 14 and the end plate 37. It is rotatably supported through. Further, the same number (three) of the eccentric portions 57 as the eccentric portions 51 of the input shaft 21 are formed at the axial center portion of these crankshafts 55, and these eccentric portions 57 each have a roller bearing 58 interposed therebetween. It is inserted into the pinion 46 in a state. As a result, the pinion 46 becomes a carrier.
It is supported eccentrically rotatable at 38.

Reference numeral 59 denotes a cover whose outer end in the radial direction is attached to one end surface of the internal gear 39.
1. The one end opening of the through hole of the carrier 38 into which the crankshaft 55 is loosely fitted and the gap between the inner periphery of one end of the internal gear 39 and the outer periphery of the other end of the carrier 38 (the outer periphery of the end plate 37) are closed. . Since the cover 59 has a disk shape, the speed reducer
The end surface of one side of 20 is also a flat surface like the end surface of the other side. When the both end surfaces of the speed reducer 20 are flat as described above, the drive motor 23 and the braking means 26 can be mounted on either side end surface of the speed reducer 20, and as a result, the degree of freedom of mounting is reduced. The layout will be abundant.

The above-described input shaft 21, carrier 38, and internal gear 3
9, the pinion 46, the crankshaft 55, and the cover 59 reduce the rotation of the drive motor 23 as a whole, and sheave (internal gear 39).
The above-mentioned reduction gear 20 is constituted. If the speed reducer 20 is of the center crank type, the speed reducer 20 and the drive motor 23 can be easily arranged coaxially.

As described above, both ends in the axial direction of the input shaft 21 of the speed reducer 20 are rotatably supported by the carrier 38 (fixed portion) of the speed reducer 20 via the bearing 50, that is, the input shaft 21
The two-sided support of the input shaft 21 and the other end of the input shaft 21 close to the drive motor 23
The rotation shaft 19 is connected to the case 16 of the drive motor 23.
(The fixed portion) can be smoothly rotated integrally with the input shaft 21 without being rotatably supported by the (fixed portion). As a result, a bearing for supporting the rotating shaft 19 is not required, and The axial length is shortened, the structure is simple, and the manufacturing cost is low. Moreover, as described above, the rotating shaft of the drive motor 23
When the input shaft 21 of the reduction gear 20 is connected to the radially inner end of the rotary shaft 19 and the input shaft 21 can be further shortened, and the input shaft 21 can be further reduced.
Can be reduced in the rotation support portion of the motor.

Here, when the rotating shaft 19 of the drive motor 23 is connected to the other end of the input shaft 21 as described above, a large load acts on the input shaft 21 of the speed reducer 20. For example, the input shaft 21 and the carrier 38 (fixed portion) of the speed reducer 20 have a deep groove ball bearing as described in the related art.
If it is interposed between the input shaft 21 and the input shaft 21, the input shaft 21 and the rotating shaft 19 may be largely shaken during rotation.

However, in this embodiment,
Since the bearing 50 is an angular ball bearing having almost no radial clearance (can be reduced to zero by applying a preload), the above-described shaft runout can be effectively suppressed. In addition, since the pair of angular ball bearings 50 are arranged in a state where the outer ring 50a is back-to-back, that is, in a state where the back surfaces of the outer ring 50a are opposed to each other, the location of the point of application of the bearing load (the configuration of each The intersection of the extension line of the contact line of the rolling element and the shaft center line, that is, the distance between the intersections) is set when the outer ring 50a is face-to-face,
50 is longer than when the front faces of the outer rings 50a are opposed to each other, and the bearing rigidity, for example, the moment load capacity is improved,
As a result, the aforementioned shaft runout is effectively suppressed,
Motor noise is effectively reduced.

Reference numeral 61 denotes a sealing member interposed between the outer periphery of the other end of the input shaft 21 and the inner periphery of the other end of the carrier 38, and 62 denotes an internal gear.
The seal member is interposed between the outer periphery of the other end of the carrier 39 and the inner periphery of the other end of the carrier 38 (the inner periphery of the large-diameter portion 13). All of them are closed, and the inside of the speed reducer 20 is sealed. When the inside of the speed reducer 20 is sealed by the seal members 61 and 62 in this way, when assembling the speed reducer 20 with the drive motor 23 and the braking means 26, it is not necessary to arrange another seal member therebetween. This facilitates the above-mentioned assembling work.

An encoder 66 is disposed radially inward of the braking means 26 and fixed to the case 16 as a detector.
The rotation speed of the sheave (internal gear 39) is detected by detecting the rotation speed of the input shaft 21 and being connected to the other end of the input shaft 21.
By arranging the encoder 66 radially inside the braking means 26 in this way, even when a detector such as the encoder 66 is added to the motored reduction gear 11, the axial length of the motored reduction gear 11 increases. Can be prevented.

Next, the operation of the first embodiment of the present invention will be described. When raising and lowering the elevator car, the coil 18 of the drive motor 23 is energized to rotate the permanent magnet 22 together with the rotating shaft 19. At the same time, the electromagnet 33 of the braking means 26 is also energized to attract the shoes 29a, 29b and move radially inward against the springs 32a, 32b. Thereby, the shoes 29a and 29b are separated from the inner periphery of the rotating shaft 19,
The drive motor 23 is released from braking. As a result, the rotating shaft 19
Rotation of the input shaft 21 without being braked by the braking means 26
To rotate the input shaft 21.

When the input shaft 21 rotates in this manner, the pinion 46 rotates eccentrically (revolves).
And the number of external teeth 47 are slightly different.
The rotation of 21 is greatly reduced by the eccentric rotation of the pinion 46 and transmitted to the internal gear 39 to rotate the internal gear 39 (sheave) at low speed. As a result, the main rope hung around the sheave groove 41 travels, and the car moves up and down. At this time, the rotation speed of the internal gear 39 is detected by the encoder 66, and the height position of the car is controlled.

Next, when stopping the elevation of the car, the energization of the coil 18 is interrupted to stop the drive of the drive motor 23, and the energization of the electromagnet 33 is also interrupted. Stop the suction of b. As a result, the shoes 29a, b
Is moved radially outward by the urging force, and is pressed against the inner periphery of the rotating shaft 19. As a result, the rotating shaft 19 has the shoe 29a,
The rotation is regulated by the frictional resistance between the drive motor
A braking force is applied to 23, and the elevator is stopped.

FIG. 4 is a view showing a second embodiment of the present invention. In this embodiment, a tapered roller bearing having almost no radial gap is used as the bearing 50. As a result, shaft runout can be effectively suppressed as described above. Moreover, the pair of tapered roller bearings 50
Are arranged in a state where the outer ring 50a is back-to-back, so that the dimension of the point of application of the bearing load is lengthened and the bearing rigidity is improved as described above, thereby effectively suppressing the aforementioned shaft runout. can do. Other configurations and operations are the same as those of the first embodiment.

In the above-described embodiment, the rotating shaft
Although the other end of the input shaft 21 is connected to the inner end in the radial direction of 19 by a wedge member 24, in the present invention, these rotary shafts and input shafts are connected by a key, a press fit, and a spline. Is also good. Further, in the above-described embodiment, a cylindrical roller follower is provided outside the internal tooth pin 42.
Although 43 is fitted, in the present invention, a cylindrical bearing may be fitted outside the internal tooth pin. Further, in the above embodiment, the pinion
Although the crankshaft 55 having the eccentric portion 57 is inserted into the 46, in the present invention, a cylindrical pin may be inserted. Further, in the above-described embodiment, the eccentric oscillating speed reducer 20 is used as the speed reducer, but the speed reducer may be of any type.

[0039]

As described above, according to the present invention, the motor noise can be easily reduced by suppressing the shaft runout of the input shaft and the rotating shaft.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a first embodiment of the present invention.

FIG. 2 is a front sectional view near the input shaft.

FIG. 3 is a view taken in the direction of arrows II in FIG. 1;

FIG. 4 is a front sectional view showing the vicinity of an input shaft according to a second embodiment of the present invention.

[Explanation of symbols]

 11 ... reducer with motor 19 ... rotating shaft 20 ... reducer 21 ... input shaft 23 ... drive motor 38 ... fixed part 50 ... bearing 50a ... outer ring

Claims (2)

[Claims] 1. A reduction gear with a motor constructed by assembling a rotation axis of a drive motor with an input shaft of a reduction gear while maintaining a coaxial relationship, wherein both ends of the input shaft of the reduction gear in the axial direction are fixed to the reduction gear. The outer ring is rotatably supported via a pair of angular ball bearings whose back faces are aligned with each other, and the rotating shaft of the drive motor is coupled to the end of the input shaft of the speed reducer that is close to the drive motor. A reduction gear with a motor. 2. A reduction gear with a motor constructed by assembling a rotation axis of a drive motor with an input shaft of the reduction gear while maintaining a coaxial relationship, wherein both ends of the input shaft of the reduction gear in the axial direction are fixed to the reduction gear. The outer ring is rotatably supported via a pair of tapered roller bearings, the outer rings of which are back-to-back, and the rotating shaft of the drive motor is coupled to the end of the input shaft of the speed reducer that is close to the drive motor. A reduction gear with a motor.