JPH0681908A - Planetary gear reducer - Google Patents

Abstract

(57) [Summary] [Purpose] To improve lubrication between a female spline portion provided at an output portion of a hydraulic motor in a planetary gear speed reducer and a male spline portion of a rotary shaft meshing with the female spline portion. [Structure] Female spline 2 provided at the output of the hydraulic motor
A male spline 12A of the rotary shaft 12 that transmits rotation to the reduction gear mechanism is engaged with A. On the outer periphery of the male spline 12A, a pair of oil guide grooves 12C and 12D deeper than the bottom of the spline tooth are provided in a reverse screw shape. With the rotation of the rotary shaft 12, the lubricating oil is introduced into the oil guide grooves 12C, 1
Flow in 2D.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planetary gear speed reducer used for, for example, a drive device for a crawler track in a hydraulic excavator, a hydraulic crane, a rope winch for a hydraulic crane, and the like.

[0002]

2. Description of the Related Art Next, as an example of this type of planetary gear reduction device, a conventional crawler belt drive device for a hydraulic excavator or the like having a three-stage planetary gear mechanism will be described with reference to FIGS. explain.

As shown in FIG. 6, a hydraulic motor 2 as a prime mover is attached to a motor attachment portion provided at one end of a cylindrical support member 1 fixed to a machine frame of a vehicle body. A carrier fixing portion 1A is formed on the other end side. Further, the female spline 1 is provided on the inner peripheral side of the support member 1.
B is formed, and a male screw 1C is provided on the outer peripheral side.

The cylindrical housing 3 with a lid, which is a rotating body, is
The drum 4 located on the outer peripheral side of the support member 1, the ring gear 5 provided with the inner gear 5A on the inner peripheral side, and similarly the internal gear 6
It is composed of another ring gear 6 provided with A and a lid 7 that covers the outside of the ring gear 6. The drum 4 is rotatably supported by the support member 1 via a bearing 8, and a crawler belt driving sprocket wheel 9 is attached to the outer peripheral side thereof. Both ring gears 5 and 6 are fastened to the drum 4 by bolts 10, and the lid 7 is fastened to the ring gear 6 by bolts 11.
Has been concluded.

A male spline portion 12A fitted to a female spline portion 2A provided at an output portion of the hydraulic motor is formed at one end of a rotary shaft 12 which transmits output rotation of the hydraulic motor 2, and a lid 7 is formed. The sun gear 14 is integrally formed on the other end side protruding from the side. The end surface portion of the rotating shaft 12 projects into the prepared hole 2B of the female spline portion. Sun gear 1
4 may be a member separate from the rotary shaft 12 and may be attached to the rotary shaft 12.

The reduction gear mechanism 13 of the first stage is the sun gear 1
4, the sun gear 14 and the internal gear 6A of the ring gear 6 are arranged so as to mesh with each other, and a planetary gear 15 that revolves around the sun gear 14 while revolving around the sun gear 14 and the planetary gear 15 are rotatable via bearings 16. The pin 17 that supports the pin 17 and the carrier 18 that fixes the pin 17 and that transmits the revolution of the planetary gear 15 to a second-stage sun gear 20 described later.

The second stage reduction gear mechanism 19 includes a rotary shaft 12
Is loosely fitted to the spline portion 18 of the first stage carrier 18
A sun gear 20 that meshes with A and rotates integrally therewith
And a planet gear 21 that meshes with the sun gear 20 and the internal gear 6A of the ring gear 6 and revolves around the sun gear 20 while rotating, and a pin that rotatably supports the planet gear 21 via a bearing 22. 23 and its pin 23 are fixed, and the orbit of the planetary gear 21 will be described later.
6 and a carrier 24 which is transmitted to the carrier 6.

The reduction gear mechanism 25 of the third stage, that is, the final stage is loosely fitted on the rotary shaft 12 and is held by the carrier 24 of the second stage.
A sun gear 26 that meshes with and rotates integrally with the spline line portion 24A, and a planetary gear 27 that is arranged around the sun gear 26 so as to mesh with the sun gear 26 and the internal gear 5A of the ring gear 5, A pin 29 that rotatably supports the planetary gear 27 via a bearing 28, and the pin 29 is fixed, and the support member 1 is attached to the outer periphery on one end side.
A male spline 30A that meshes with the female spline 1B is formed, and includes a carrier 30 that is positioned by the support member 1 in the axial direction and the rotation direction. Carrier 3
0 is the side plates 30B and 30 on both sides supporting the pin 29.
C and a rib 30D extending between and connecting both side plates 30B and 30C. The side plate 30B is adjacent to the male spline 30A and projects diametrically.
It is also formed in a plate shape and is joined to the end surface of the carrier fixing portion 1A of the support member 1.

Further, the carrier fixing portion 1A of the support member 1
A nut 31 for axially positioning the bearing 8 is fitted in a male screw 1C provided on the outer periphery of
The nut 31 is prevented from rotating by a key plate 32 and a bolt 33.

In the planetary gear speed reducer configured as above, when the hydraulic motor 2 is driven, the rotation thereof is the sun gear 1
4, the first stage reduction gear mechanism 13 including the planetary gears 15, the carrier 18 and the like reduces the speed at a predetermined reduction ratio, and only the revolution of the planetary gears 15 is transmitted from the carrier 18 to the second stage sun gear 20. Then, the second reduction gear mechanism 1 including the sun gear 20, the planetary gear 21, the carrier 24, and the like.
9 further reduces the rotation from the carrier 24 at a predetermined reduction ratio, and transmits only the revolution of the planetary gear 21 from the carrier 24 to the sun gear 26 at the final stage. Furthermore, the sun gear 26,
In the final stage reduction gear mechanism 25 including the planetary gear 27, the carrier 30, etc., the carrier 30 has a male spline 30A,
Since the rotational output from the carrier 30 is decelerated at a predetermined reduction ratio, the rotational output from the carrier 30 is decelerated at a predetermined reduction ratio because the female spline 1B is used to position the supporting member 1 in the rotational direction.
7 to the ring gear 5, and the ring gear 5,
A large rotational torque is generated in the housing 3 including the ring gear 6 and the drum 4.

As described above, the rotational output of the hydraulic motor 2 is sequentially decelerated by the reduction gear mechanisms 13, 19, 25,
A large torque is transmitted to the housing 3, and a crawler belt (not shown) wound around the sprocket wheel 9 is driven, so that a hydraulic excavator or the like travels.

[0012]

In the planetary gear speed reducer described above, the hydraulic motor 2 is used as the fitting portion for the constituent parts.
A female spline portion 2A of the output end, a male spline portion 12A of the rotary shaft 12, a spline portion 18A of the carrier 18, a spline portion 20A of the sun gear 20, a spline portion 24A of the carrier 24 and a spline portion 26A of the sun gear 26,
There is a female spline portion 1B of the support member 1 and a male spline portion 30A of the carrier 30. Of these, the female spline portion 2A and the male spline portion 12A in the first stage rotate at a higher speed than those in the mating portions in the other stages and are exposed to slight vibration between the tooth surfaces, so that the lubrication state is insufficient. And there is a problem that causes fretting damage. By the way, conventionally, as shown in FIG. 7 and FIG. 8, since the lubricating oil only moves through the small gaps 2G and 12G of the spline portion, poor lubrication may occur if it happens. This invention
The purpose is to eliminate this difficulty easily.

[0013]

In order to achieve the above object, the present invention provides a spline root at the outer periphery of a male spline portion of a rotary shaft fitted to a female spline portion provided at an output portion of a prime mover. It is characterized in that a pair of deeper oil-conducting grooves are provided in mutually opposite screw shapes.

[0014]

[Function] With the rotation of the rotary shaft, the lubricating oil flows through the oil guide groove.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described. In these drawings, the same members as those in FIG. 6 are designated by the same reference numerals.

On the outer circumference of the male spline portion 12A of the rotary shaft 12, a pair of oil guide grooves 12C and 12D, which are deeper than the spline tooth bottom 12B, are provided in reverse screw shapes.

When the rotary shaft 12 rotates clockwise in FIG. 3, the lubricating oil is sent along the screw-shaped oil guide grooves 12C and 12D in the direction of the arrow shown in FIGS. Since the oil guide grooves 12C and 12D have mutually reverse threaded shapes, with respect to the prepared hole 2B of the female spline portion 2A of the hydraulic motor 2,
The effect of inflow and outflow of lubricating oil occurs. The solid arrow in FIG. 1 indicates the direction of flow of the lubricating oil. At this time, the lubricating oil shunted from the oil guide grooves 12C and 12D spreads to the teeth of the female spline portion 2A and the male spline portion 12A.

[0018]

According to the present invention described above, lubrication between the female spline portion of the output portion of the prime mover and the male spline portion of the rotary shaft can be easily made favorable, and damage to the spline tooth surface due to poor lubrication can be prevented. be able to.

[Brief description of drawings]

FIG. 1 is a sectional side view (a sectional view taken along the line AA of FIG. 3) showing an embodiment of the present invention.

2 is a sectional side view showing only the rotary shaft of FIG.

3 is an end view of the rotary shaft of FIG. 2,

4 is a left side view of FIG. 3,

5 is a right side view of FIG.

FIG. 6 is a sectional side view showing an example of a conventional planetary gear speed reducer,

FIG. 7 is an enlarged view showing a female spline portion and a male spline portion of a rotary shaft of the hydraulic motor of FIG.

FIG. 8 is a sectional view taken along line CC of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support member 2 Hydraulic motor 2A Female spline part 3 Housing 12 Rotating shaft 12A Male spline part 12C Oil guide groove 12D Oil guide groove 13 1st reduction gear mechanism 19 2nd reduction gear mechanism 25 3rd reduction gear mechanism

Claims (1)

[Claims] 1. A support member, a cylindrical housing with a lid, which is rotatably supported by the support member and has an internal gear on the inner peripheral side, a prime mover provided on the support member, and one end side,
A planetary gear having a rotating shaft formed with a male spline part fitted to a female spline part provided at the output part of the prime mover, and a reduction gear mechanism having an arbitrary number of stages for decelerating the rotation of the rotating shaft and transmitting it to the housing. A planetary gear speed reducer in which a pair of oil guide grooves deeper than the bottom of the spline tooth root are provided in a reverse screw shape on the outer periphery of the male spline portion of the rotary shaft.