JPS5993552A - Reduction gear using planetary gear mechanism - Google Patents

Abstract

PURPOSE:To reduce the number of snap rings to provide a compact reduction gear as a whole by regulating positionally an end of a plurality of carrier cases with the snap ring and regulating positionally the other surfaces with the wall surface of the case to interpose washer members between the carrier cases. CONSTITUTION:The regulation of the engaging position of carrier cases 12a, 12b engaging with sun gears 10b, 10c arranged at multiple stages to rotate independently is performed by the slide of the inner wall of an output case 2 on an annular projection 2a and the fitting of a snap ring in the sun gear 10c. A washer 14 is interposed between the carrier cases 12a, 12b to regulate the engaging positions of the carrier case 12a and the sun gear 10b and the carrier case 12b and the sun gear 10c. This facilitates the production of a reduction gear and provides a compact and light one to improve the efficiency of the reduction gear.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a fi
Concerning a reduction gear using a star gear mechanism.

2. Description of the Related Art Conventionally, there is a reduction gear as shown in FIG. 1, which uses an M star gear and is used for swing driving of construction machinery.

In Fig. 1, 1 is a fixed case fixed to a base, 2
is an output case that is rotatably attached to a fixed case 1 via a bearing 3, and sun gears 4a, 4b, and 4C are arranged in multiple stages in the case so that they can rotate independently in the axial direction, and are fixed to the input shaft. A planetary gear 6a is engaged with the sun gear 4a, which is supported by a carrier case 5a, and the carrier case 5a is engaged with the next sun gear 4b. Further, the sun gear 4b is similarly engaged with a planetary gear 6b supported by a carrier case 5b, and the carrier case 5b is engaged with the final stage sun gear 4C. The final stage sun gear 4G has a planetary gear 6 supported on the fixed case 1.
The output case 2 is connected to the output case 2 by meshing with the coupling gear 7.

Therefore, the input rotation to the sun gear 4a is decelerated by the three-stage planetary gear mechanism, and finally brings about the decelerated rotation of the output case 2.

By the way, in a multi-stage planetary gear mechanism not shown in Fig. 1,
Carrier case 5a due to thrust force generated during rotation
, 5 [] and the meshing position with respect to the sun gears 4a and 4b, the right end of the first-stage Kyrelia case 5a is positioned by sliding contact with the inner walls of Arara 1 to Pututsu case 2, and the Kyrelia case 5a For the left side and carrier case 5b, sun gear 4b, 4c
The engagement position is regulated by fitting the snap ring 8 into a groove formed on the tooth surface.

However, when a snap ring is used, it is necessary to machine fitting grooves in one place for sun gear 4b and two places for sun gear 4c, and the axial direction of sun gears 4b and 4c is changed by the amount of shaping the fitting grooves. There was a problem in that it was difficult to assemble because the length had to be increased and the snap ring had to be fitted in a narrow space.

The present invention was made in view of these conventional problems, and provides a speed reducer using a planetary gear mechanism that reduces the number of snap rings used to regulate the positions of multiple carrier cases in a multi-stage planetary system. The purpose is to provide.

In order to achieve this object, the present invention has one end of a plurality of carrier cases arranged in sequence regulating the position by fitting a snap ring, and the other end regulating the position by sliding contact with the wall surface of the case, and furthermore, each carrier A washer ring that slides on the end surface of the carrier case is interposed between the cases to regulate the position, and only one snap ring is needed regardless of the number of stages, and there is no fitting groove for the sun gear. This is to reduce the number of machining points and to downsize the sun gear.

Hereinafter, embodiments of the present invention will be explained based on the drawings.

FIG. 2 is a partial cross-sectional explanatory diagram showing an embodiment of the present invention, and takes as an example the speed reduction used for the swing drive of a construction machine, which is the same as the conventional example shown in FIG.

First, to explain the structure, 1 is a fixed case fixed to a base, 2 is a holder 1 to a putter that is rotatably attached to the fixed case 1 with a bearing 3, and inside the case is a sun gear, a carrier case, and A planetary gear mechanism consisting of planetary gears is incorporated in three stages in the axial direction, and Figure 2 shows a cross section of only the meshing part of the carrier case with the sun gear. The sun gear is omitted because it is the same as the conventional device shown in FIG.

That is, the sun gear 10a rotates while being fixed to the input shaft.
Carrier case 1 bearing a planetary gear that meshes with the
2a is meshed with the next stage sun gear 101), and the kitria case 12b bearing a planetary gear that meshes with the sun gear 10b is meshed with the final stage sun gear 10c, and the planetary gear that meshes with the final stage sun gear 10 is mounted on the fixed case 1. The bearing of the fixed shaft is engaged with the internal teeth of the coupling gear 7, and the coupling gear 7 is connected to the 7 outputs 1 to 2 through the engagement connection.

The meshing position of the carrier cases 12a and 12b that are meshed with the sun gears 1ob and 10c arranged in multiple stages in this way is firstly restricted by sliding the right side G3 of the carrier case 12a against the annular protrusion 2a formed on the inner wall of the output case 2. The left side of the carrier case 12b is positioned by fitting the snap ring 8 to the sun gear 10c, and a washer 14 is interposed between the carrier cases 12a and 12b. 12a, 12
Kitria case 12 against sun gear 10b by sliding contact of b
The structure is such that the engaging position of the carrier case 12b is regulated with respect to the sun gear 10c, and the engaging position of the carrier case 12b with respect to the sun gear 10c is regulated.

Therefore, the two-stage carrier case 1 in the embodiment of FIG.
2a and 12b, only one snap ring 8 and washer 14 are required, and medium heat sun gear 10 is required.
As for b, there is no need to form a fitting groove for fitting the washer, and it is only necessary to form a fitting groove at one location on the sun gear 10C, so the number of processing steps can be significantly reduced.

On the other hand, when assembling the planetary gear (gear mechanism), first assemble the snap ring 8 to the sun gear 10C in advance, and in this state, sequentially from the sun gear IOC side, carrier case 12b1 sun gear 10b, wire t1
4. Since the gear mechanism can be assembled by sequentially assembling the sun gear 10a in the carrier case 12a1, the assembly work is easier than in the conventional structure, which required a washer ring to be fitted each time the carrier case was assembled. I can do it.

Furthermore, since the snap ring only needs to be provided at one location on the sun gear 10C at the final stage of R, the length in the axial direction of the sun gears 101] and 10c can be shortened by the amount that was conventionally fitted with a snap ring. With the downsizing of the sun gear, naturally the outboards 1 to 2 can also be downsized, and the reduction gear itself can also be made lighter.

Furthermore, in the reduction gear of the present invention, efficiency can be further improved compared to conventional devices.

That is, in the conventional structure shown in FIG.
The thrust force generated is applied to each of the sun gears 4b and 4C via the snap ring 8, causing a loss due to the positive force. On the other hand, in the embodiment of the present invention shown in FIG. As a result, only a thrust force is applied to the left direction of the carrier case 12b, and as a result, the kitria cases 12a, 12
1 (1) due to the fact that the washer 14 was interposed between
The loss is offset by the fact that the force is not transmitted from the carrier case side to the sun gear 1011 to the thrust 1, and even if the loss due to the D washer 1714 is added, the loss due to one washer ring 8 is sufficiently small compared to the conventional structure. As a result, the structure of the present invention achieves higher efficiency than the conventional structure.

Although the above embodiment takes a three-stage planet as an example, it can be applied as is to a reduction gear using a multi-stage M star gear mechanism in which at least two or more stages of carrier cases are connected in the axial direction. Of course.

As is clear from the above description, in the reduction gear using the planetary gear mechanism of the present invention, the position of the plurality of gears 11 arranged in the axial direction is limited only at one end of the rear case by L&I of the snap ring relative to the sun gear. However, since the position between the carrier cases can be regulated by intervening washers, the washer ring used for positioning the carrier case only needs to fit in one place, which reduces machining errors of the snap ring fitting '4 f+S to the sun gear. , the assembly of the planetary gear mechanism is easy, and the snap ring is one ring.
Since the number of fitting grooves formed in the sun gear is reduced, it is possible to reduce the axial dimension of the sun gear, and the reduction gear can be made smaller and lighter.

In addition, as an effect unique to the present invention, the loss caused by the washer used instead of the snap ring is offset by not allowing the thrust force of the Kitria case to act on the sun gear, and the loss is smaller than when using the snap ring. Therefore, the efficiency of deceleration release can be further improved.

[Brief explanation of the drawing]

b') Figure 1 is a sectional view showing a conventional example, and Figure 2 is a partial sectional view showing an embodiment of the present invention. 1: Fixed case 2 Near-end case 3: Bearings 5a, 6b, 5c: Flange') ') Key 7
7: Coupling gear 8 Nut spring 10a, 10b, 10C: +j>Gear 12: Carrier case 14: Washer 1? Patent applicant: Fuji Iron Works Co., Ltd. Agent: Susumu Juuchi, patent attorney

Claims (1)

[Claims] A plurality of sun gears are arranged in multiple stages so as to be able to rotate independently on the same axis, and a plurality of gears 11 rear cases are meshed and fitted for each sun gear, and a snap ring t+Xf with respect to the sun gear is arranged in multiple stages so that they can rotate independently.
In a reducer using a planetary gear m diagram whose position is regulated in the axial direction by f1, one end of a plurality of carrier cases arranged in multiple stages in the axial direction is fitted with a snap ring to the sun gear to regulate the position, and the other end is A speed reducer using a planetary gear mechanism, characterized in that the position is regulated by a case wall surface, and a washer member of a specified width is interposed between each carrier case so as to be in sliding contact with the end surface of the case.