JP2007232082A - Reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reduction gear which has fewer component items, and is built in a compact size, and transmits rotation smoothly by reducing the run-out of the axis of a gear. <P>SOLUTION: The reduction gear comprises an input-side rotary body 1 having external gear 18, and an output-side rotary body 2 provided with an internal gear 28 having a more number of teeth than that of the external gear 18. Rotation axes L<SB>1</SB>, L<SB>2</SB>of the external gar 18 and the internal gear 28 are mutually eccentrically provided to mesh the external gear 18 and the internal gear 28 with each other. An eccentrically holding member 4 is connected to the rotary bodies 1, 2 by means of bearings 8, 9 respectively so as to be freely idled. The eccentrically holding member 4 holds the rotary bodies 1, 2 so that the eccentricity ε of the rotation axes L<SB>1</SB>, L<SB>2</SB>of the rotary bodies 1, 2 becomes constant. A drive shaft 37 of an electric motor 36 is directly interlocked to the input-side rotary body 1, and a rotation shaft 39 of a driven device 38 is directly interlocked to the output-side rotary body 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a speed reducer that transmits power by connecting an electric motor (motor) and a driven device.

As a conventional speed reducer, a first gear with an external gear and a second gear with an external gear are provided. The first gear is connected to the output shaft of the motor as the same axis, and the second gear is connected to a wheel. The first gear is engaged with the second gear in an eccentric state, and the motor is driven by decelerating the rotation of the motor and transmitting it to the wheels (see, for example, Patent Document 1).
JP-A-8-2266

  Such a conventional speed reducer requires many parts such as a bearing member for each gear. Further, since each gear meshes with the external gears, a large space is required and a space for parts such as a bearing member is also required, so that the structure of the speed reducer itself becomes large overall. And since the structure is complicated, the cause of failure tends to increase. In addition, grease oil or the like scatters due to the rotation of the circumscribed gear. In order to guard and seal this, these parts need to be surrounded by a sealed casing, resulting in a larger structure. Furthermore, since the gears mesh with each other and rotate, the shaft centers of both gears are likely to swing, and the meshing accuracy is likely to be reduced. Thus, there is a possibility that power transmission cannot be performed smoothly. And there also exists a fault that the cost concerning a bearing member etc. becomes large in order to prevent this.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a speed reducer that can be formed into a compact size and shape with a small number of parts, and that smoothly transmits rotation by preventing the shaft center of a gear from swinging. And

  In order to achieve the above object, a reduction gear according to the present invention includes an input-side rotator having an external gear, and an output-side rotator having an internal gear having more teeth than the external gear. The rotational gears of the external gear and the internal gear are arranged eccentrically with each other, and the external gear and the internal gear are engaged with each other.

  Further, between the input-side rotator and the output-side rotator, both the rotators are connected to each other via a bearing so as to be freely rotatable, and the eccentric distances of the respective rotation shafts are constant. An eccentric holding member for holding as described above was provided.

A sealing cover member having a hole that fits around the input-side rotator and having an outer peripheral edge surrounding the output-side rotator, the sealing cover member being attached to the hole; And a first seal member that slidably contacts the outer peripheral surface of the input-side rotator, and a second seal member that is attached to the surrounding portion and slidably contacts the outer peripheral surface of the output-side rotator.
The sealing cover member is connected and fixed to the eccentric holding member.
Further, the drive shaft of the electric motor is directly linked to the input side rotating body, and the rotating shaft of the driven device is directly linked to the output side rotating body.

The present invention has the following remarkable effects.
Since the speed reducer according to the present invention is configured to eccentrically mesh the external gear of the input-side rotator with the internal gear of the output-side rotator, it is possible to suppress both shafts from swinging during rotation. Therefore, highly accurate meshing rotation can be performed and rotation can be transmitted smoothly. And, since the input side rotating body and the output side rotating body are interposed between the motor and the driven device and the motor and the driven device are connected, the number of parts is small and the overall size is also It can be made compact. In addition, the reduction gear can be easily processed and assembled, and it does not take time to mount the reducer on an electric motor or a driven device.

In addition, since the input side rotator and the output side rotator are connected by an eccentric holding member between them through the bearing, it is possible to reliably prevent the shafts of both the rotators from shaking and to rotate more smoothly. Can communicate.
Further, by attaching the sealing cover member to the rotating body, it is possible to guard against the rotation of the rotating body and splashing of lubricating oil such as grease to the surroundings due to centrifugal force, and it is possible to reliably prevent leakage. Therefore, it is possible to prevent the equipment installation location from being contaminated with grease or the like. Moreover, since the sealing cover member can be easily attached and removed, it does not require assembling work.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments.
FIGS. 1 to 10 show an embodiment of a speed reducer according to the present invention, which is interposed between an electric motor (motor) 36 and a driven device 38 such as a pump of a washing machine, and transmits the speed reduced. Is. This reduction device includes an input-side rotator 1 having an external gear 18 and an output-side rotator ₂ having an internal gear 28 having a number of teeth N ₂ larger than the number of teeth N ₁ of the external gear 18. To do.
First, as shown in FIGS. 1 to 4, the input side rotating body 1 includes a cylindrical portion 12 having an insertion hole portion 11 into which a drive shaft 37 of an electric motor 36 is inserted and fixed, and the other end of the cylindrical portion 12. The external gear 18 projecting in the outer radial direction at the close part is integrally formed, and the insertion hole 11 and the external gear 18 are formed to have the same first axis L _1. . Further, the outer peripheral surface 10 of the cylindrical portion 12 is formed with a small step portion 13a on the other end edge portion, with a fixing surface portion 13 to which a bearing 8 (described later) is fitted and fixed. Moreover, insertion holes 11 of the cylindrical portion 12, the key groove 11a of the key formed on the drive shaft 37 of the motor 36 is engaged, with the axis L ₁ direction. The cylindrical portion 12 has a female screw hole extending through the inner and outer peripheral surfaces, and a male screw is screwed into the female screw hole to press the outer peripheral surface of the drive shaft 37 (or a key is formed). The drive shaft 37 is prevented from being pulled out.
The power input side (motor side) is one side, and the output side (driven device side) is the other side.

Next, as shown in FIGS. 1 and 2, the output side rotating body 2 includes a disk-shaped rotating member 20 into which the rotating shaft 39 of the driven device 38 is inserted, and an internal gear 28. And a ring-shaped gear member 26 that is fixed to the ring.
Specifically, in FIGS. 1, 2, 5, and 6, the rotating member 20 has a disk portion 25 and a bent circumferential shape formed by bending the outer peripheral edge of the disk portion 25 on one side. Part 21 and an insertion cylindrical part 22 projecting from the central part of the other surface of the disk part 25 and into which the rotation shaft 39 of the driven device 38 is inserted, and this insertion cylindrical part 22 The bent circumferential portion 21 is formed to have the same second axis L ₂ . Insertion hole 23 of the insertion cylindrical portion 22, the key groove 23a of the key of the rotating shaft 39 of the driven device 38 is engaged is formed in the axial L ₂ direction. The insertion cylindrical portion 22 has a female screw hole extending through the inner and outer peripheral surfaces. The male screw is screwed into the female screw hole to press the outer peripheral surface of the rotary shaft 39, thereby rotating the insertion cylindrical portion 22. The shaft 39 is retained. The surface of one side of the disk portion 25, the bearing fitting recess 24 to fix it fitted in the (described later) radial bearing 9 is recessed in the second axis L ₂ of the same axis shape. In the illustrated example, the bearing fitting recess 24 and the insertion hole 23 are formed continuously. Further, the inner peripheral surface of the bent peripheral portion 21 has a fixed inner surface portion 21b that is formed in an enlarged diameter shape with a stepped portion at one end edge side and to which the gear member 26 is fitted and fixed.
1, 7, and 8, the ring-shaped gear member 26 is formed in a short cylindrical shape and has an internal gear 28 on the inner peripheral surface. A stepped portion 27 is formed on the other side of the outer peripheral edge of the gear member 26, and if the stepped portion 27 of the gear member 26 is fitted to the fixed inner surface portion 21 b of the rotating member 20, the output side rotating body 2. Is formed (see FIG. 1).

As shown in FIGS. 1, 2, 9, and 10, between the input side rotary body 1 and the output side rotary body 2, both rotary bodies 1 and 2 are connected to the rotation axis L ₁ , L. An eccentric holding member 4 that holds the eccentric distance ε of ₂ to be constant is disposed. The eccentric holding member 4 is connected to both rotating bodies 1 and 2 via radial bearings 8 and 9, respectively, so as to freely rotate.
Specifically, the eccentric holding member 4 has a substantially flat plate shape, and has the same axis as the second axis L _{2 at} the substantially central portion of the other side surface of the eccentric holding member 4, and is on the output side. A short columnar fitting convex portion 42 that fits into the bearing fitting concave portion 24 of the rotating body 2 (via the bearing 9) is projected. Also, on one side surface of the eccentric retainer member 4, the first around the axis L _1, the fixation surface portion 13 of the input side rotating body 1 (via the bearing 8) for mating circular A fitting recess 41 is formed. As described above, since the shaft centers L ₁ and L ₂ have a certain eccentric distance ε, the fitting recess 41 is formed at a position off the center in the eccentric holding member 4.
Further, on one side of the eccentric holding member 4, a female screw 43 to which a connecting bolt 6 to be described later is screwed is positioned substantially symmetrically with respect to the fitting recess 41 (with respect to the second axis L ₂ ). It is formed.

In FIG. 1, the speed reducer according to the present invention surrounds the input side rotating body 1 and the output side rotating body 2, and lubricating oil such as grease attached to the external gear 18 and the internal gear 28 is rotated by rotation. A substantially disc-shaped sealing cover member 3 that guards against scattering is provided. The sealing cover member 3 has a disk-shaped fixed plate portion 30, and the fixed plate portion 30 has its outer peripheral edge bent to the other side, and the bent peripheral portion 21 of the output side rotating body 2 is formed. An annular encircling portion 34 that encloses from the outside is formed, and a hole 30a that is fitted around the input-side rotator 1 is penetrated in the axial direction. The sealing cover member 3 includes a first seal member 31 attached to the hole 30a and slidably in contact with the outer peripheral surface 10 of the input-side rotator 1, and a bent peripheral portion of the output-side rotator 2 attached to the surrounding portion 34. And a second seal member 32 slidably in contact with the outer peripheral surface 21a of 21. The first and second seal members 31 and 32 use, for example, oil seals.
The sealing cover member 3 is fixed to the eccentric holding member 4 in a connected manner. Specifically, the fixing plate portion 30 of the sealing cover member 3 is provided with a fixing cylindrical portion 33 for fixing to the eccentric holding member 4 in a connected manner on the other surface. And the hole inside the cylindrical part 33 for fixation is penetrated from the inner part to the surface of one side, and the volt | bolt 6 can be penetrated.

Next, the procedure for assembling the reducer and attaching it to the electric motor 36 and the driven device 38 will be described.
In FIG. 1, first, the radial bearing 9 is fitted into the bearing fitting concave portion 24 of the output side rotating body 2, and the fitting convex portion 42 of the eccentric holding member 4 is fitted into the inner ring of the bearing 9. To do. Then, the radial bearing 8 is fitted into the fitting recess 41 of the eccentric holding member 4, and the fixing surface portion 13 of the input side rotating body 1 is fitted to the inner ring of the bearing 8. At this time, the external gear 18 of the input-side rotator 1 meshes with the internal gear 28 of the output-side rotator 2, and each of the rotators ₁ and ₂ has an eccentric distance ε whose axes L ₁ and L ₂ are constant. It is arrange | positioned in the state which maintained.
Then, the sealing cover member 3 is externally fitted to the input side rotating body 1 and the output side rotating body 2 through the hole 30a and the surrounding portion 34, and the first and second seal members 31 and 32 are respectively connected to the input side. The outer peripheral surface 10 of the rotating body 1 and the outer peripheral surface 21a of the bent peripheral portion 21 of the output-side rotating body 2 are brought into sliding contact. Then, when the bolt 6 is inserted into the fixing cylindrical portion 33 of the sealing cover member 3 and screwed into the female screw 43 of the eccentric holding member 4, the sealing cover member 3 is connected to the eccentric holding member 4. Fixed. The setting of the reduction gear is completed by the above procedure.

  Next, the driven device 38 is fixed on the base 7, the insertion cylindrical portion 22 of the output side rotating body 2 of the speed reducer is externally fitted to the rotating shaft 39 of the driven device 38, and the screw is inserted. The rotary shaft 39 is prevented from being pulled out by being screwed onto the female screw of the embedded cylindrical portion 22. The key of the rotary shaft 39 is engaged with the key groove 23a. Next, the electric motor 36 is placed on the base 7 and fixed while the drive shaft 37 of the electric motor 36 is inserted into the insertion hole 11 of the input side rotating body 1. Further, a screw is screwed onto the female screw of the rotating body 1 to prevent the drive shaft 37 from being removed. In this way, the drive shaft 37 of the electric motor 36 is directly linked to the input side rotating body 1 and the rotating shaft 39 of the driven device 38 is directly linked to the output side rotating body 2.

When the motor 36 is started, the input-side rotating body 1 with the drive shaft 37 rotates the first axis L ₁ around, the output side rotating body 2 that meshes with this reduction in the second axis L ₂ around Rotate. Along with this, the rotating shaft 39 rotates and the driven device 38 is driven. The eccentric holding member 4 is connected to both rotary bodies 1 and 2 by bearings 8 and 9 so as to freely rotate, and the first and second axial centers L ₁ and L ₂ where the rotary bodies 1 and 2 are eccentric from each other. Since it rotates, the eccentric holding member 4 is maintained in a non-rotating state. Then, the eccentric holding member 4 allows the rotating bodies 1 and 2 to rotate smoothly because the eccentric distance ε of the shaft centers L ₁ and L ₂ is held constant and cannot be shaken with each other. Thus, it can be replaced with a V-belt or pulley used in a conventional speed reducer, and the assembly is facilitated, so that the mounting on the motor 36 and the driven device 38 is not troublesome.
Further, the sealing cover member 3 is connected to the eccentric holding member 4 and does not rotate with the rotation of both the rotary bodies 1 and 2. Therefore, the first and second seal members 31 and 32 of the sealing cover member 3 are in sliding contact with the rotating bodies 1 and 2, respectively, and the sealed state is reliably maintained.

In addition, by subjecting the external gear 18 and internal gear 28 of both rotating bodies 1 and 2 to surface hardening, both gears 18 and 28 mesh smoothly and rotate smoothly without supplying lubricating oil. To do. In this case, the sealing cover member 3 as described above is unnecessary. Examples of the surface hardening treatment include nitriding treatment, DLC (Diamond Like Coating) treatment, PVD treatment, and the like.
In addition to the pump, the driven device 38 includes various machines that are driven by inputting rotational driving force, and are connected in the same manner as described above. Further, it is preferable (not shown) that the bearings 8 and 9 themselves have a sealed structure to prevent leakage of internal grease and the like to the outside.

As described above, the speed reducer according to the present invention has an output provided with the input side rotating body 1 having the external gear 18 and the internal gear 28 having the number N ₂ of teeth greater than the number N ₁ of the external gear 18. And the rotational axes L ₁ and L ₂ of the external gear 18 and the internal gear 28 are arranged eccentrically with each other so that the external gear 28 and the internal gear 18 are mutually connected. Since they are meshed, they are easy to process and assemble, and do not require time and effort for mounting on an electric motor or driven device. Also, unlike a gear that transmits rotation by meshing external gears, a bearing member is not required and the number of parts can be reduced. In addition, the overall size can be made compact compared to the meshing that circumscribes. Further, since both shaft centers L ₁ and L ₂ can be prevented from swinging during rotation, the shafts can be meshed and rotated with high accuracy, and the rotation can be transmitted smoothly.

Further, between the input-side rotator 1 and the output-side rotator 2, both the rotators 1 and 2 are rotatably connected to the two rotators 1 and 2 via bearings 8 and 9, respectively. Since the eccentric holding member 4 is provided to hold the eccentric distances ε of the centers L ₁ and L ₂ so as to be constant, the drive shaft 37 (input-side rotating body 1) is held by the eccentric holding member 4 that is always stationary. The rotary shaft 39 (inserted cylindrical portion 22) is supported and stably held in the form of a both-end supported beam. In this way, it is possible to reliably prevent the shaft centers L ₁ and L _{2 of the} rotating bodies ₁ and ₂ from swinging, and the backlash between the teeth of the meshing portion of the external gear 18 and the internal gear 28 is always constant. High accuracy can be maintained and it can be rotated more smoothly.

  The sealing cover member 3 has a hole 30a that fits externally on the input-side rotator 1 and an annular enclosure 34 that surrounds the output-side rotator 2 on the outer edge. Since it has the 1st seal member 31 attached to 30a, and slidably contacts the outer peripheral surface 10 of the input side rotary body 1, and the 2nd seal member 32 attached to the enclosure part 34 and slidably contacts the outer peripheral surface of the output side rotary body 2 Rotating bodies 1 and 2 can be rotated to prevent lubricating oil such as grease from being scattered around by centrifugal force, and leakage can be reliably prevented. Therefore, it is possible to prevent the equipment installation location from being contaminated with grease or the like. In addition, since the sealing cover member 3 can be easily attached and detached, it does not require assembling work.

  Further, since the sealing cover member 3 is connected and fixed to the eccentric holding member 4, the eccentric holding member 4 is kept non-rotating, and therefore the sealing cover member 3 can also be kept non-rotating. , Can surely prevent leakage. In addition, it is possible to prevent dangers such as human hands and clothing getting caught in the gear meshing portion, and to maintain safety.

  Further, since the drive shaft 37 of the electric motor 36 is directly linked to the input-side rotating body 1 and the rotating shaft 39 of the driven device 38 is directly linked to the output-side rotating body 2, the power of the V belt, pulley, etc. A transmission member is unnecessary, the number of parts can be reduced, and a compact structure can be achieved.

It is a section side view showing one embodiment of a reduction gear concerning the present invention. It is AA sectional drawing of FIG. It is a cross-sectional side view which shows an input side rotary body. It is a front view. It is a cross-sectional side view which shows the rotation member of an output side rotary body. It is a front view. It is a cross-sectional side view which shows the gear member of an output side rotary body. It is a front view. It is a cross-sectional side view which shows an eccentric holding member. It is a front view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input side rotary body 2 Output side rotary body 3 Sealing cover member 4 Eccentric holding member 8 Bearing 9 Bearing
10 Outer surface
18 External gear
28 Internal gear
30a hole
31 First seal member
32 Second seal member
34 Siege
36 electric motor
37 Drive shaft
38 Driven equipment
39 Rotating shaft ε Eccentric distance L ₁ , L ₂ shaft center N ₁ , N ₂ Number of teeth

Claims (5)

An output having an input side rotating body (1) having an external gear (18) and an internal gear (28) having a number of teeth (N ₂ ) larger than the number of teeth (N ₁ ) of the external gear (18). A rotating body (2), and the rotational axes (L ₁ ) and (L ₂ ) of the external gear (18) and the internal gear (28) are arranged eccentrically with respect to each other. A reduction gear characterized in that an external gear (18) and the internal gear (28) are meshed with each other. Between the input side rotary body (1) and the output side rotary body (2), the rotary bodies (1) and (2) are connected to the rotary bodies via bearings (8) and (9), respectively, so as to freely rotate. And an eccentric holding member (4) for holding the rotary bodies (1) and (2) so that the eccentric distances (ε) of the rotary shafts (L ₁ ) and (L ₂ ) are constant. 1. The reducer according to 1.   A sealing cover member (3) having a hole (30a) fitted around the input side rotating body (1) and having an annular surrounding portion (34) surrounding the output side rotating body (2) at the outer edge; The sealing cover member (3) includes a first seal member (31) attached to the hole (30a) and slidably contacting the outer peripheral surface (10) of the input side rotating body (1), and the surrounding portion ( The speed reducer according to claim 1 or 2, further comprising: a second seal member (32) attached to 34) and in sliding contact with the outer peripheral surface of the output side rotating body (2).   The speed reducer according to claim 3, wherein the sealing cover member (3) is connected and fixed to the eccentric holding member (4).   The drive shaft (37) of the electric motor (36) is directly linked to the input side rotating body (1), and the rotating shaft (39) of the driven device (38) is directly connected to the output side rotating body (2). The speed reducer according to claim 1, 2, 3, or 4, linked to

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