JPH112314A - Planet gear speed changer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the tumbling or the like of a shaft by supporting the planetary gear shaft in a center shaft type, and improve the durability. SOLUTION: With a sun gear 2 and a ring gear 3, a plurality of planetary gears 4 are meshed, one end of a planetary gear shaft 5 supporting each planetary gear 4 is mutually connected by a holder 6, a side wall part 7A of a gear case 7 covering these members is arranged adjacent to the planetary gear shaft 5. The other end of a plurality of the planetary gear shafts 5 is mutually connected by an auxiliary holder 8, this auxiliary holder 8 is arranged through a slight clearance C with the gear case side wall part 7A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planetary gear transmission used, for example, as a speed reducer for a crawler traveling device of a backhoe.

[0002]

2. Description of the Related Art In a planetary gear transmission of this type, a plurality of planetary gears are meshed with a sun gear and a ring gear, one end of all planetary gear shafts supporting the planetary gears is connected by a holder, and a side wall of a gear case that covers the planetary gear shaft is covered by the holder. A plate member is disposed close to the planetary gear shaft, and between the planetary gear and the side wall of the gear case, a plate member for regulating the axial position of the planetary gear is arranged.

[0003]

In the prior art planetary gear transmission described above, the planetary gear can be prevented from slidingly contacting the side wall of the gear case by the position regulating plate, but the planetary gear shaft is supported by only one holder. Because of the cantilever support, the shaft is likely to fall down, causing wear and breakage.

Further, the position regulating plate is loosely fitted to the planetary gear shaft and is in sliding contact with the side wall of the gear case, so that the position regulating plate is liable to be worn or damaged. The present invention provides an auxiliary holder that supports the planetary gear shaft in combination with the holder, and forms a small gap between the auxiliary holder and the side wall of the gear case.
It is an object of the present invention to provide a planetary gear transmission that supports a planetary gear shaft at both ends, prevents the shaft from falling down, and improves the durability of the planetary gear shaft and the auxiliary holder.

[0005]

A first concrete means for solving the problems in the present invention is a planetary gear shaft 5 which meshes a plurality of planetary gears 4 with a sun gear 2 and a ring gear 3 and supports each planetary gear 4. Holder 6 at one end
And a side wall 7 of the gear case 7 which covers the
In the planetary gear transmission in which A is disposed close to the planetary gear shaft 5, the other ends of the plurality of planetary gear shafts 5 are connected to each other by an auxiliary holder 8, and the auxiliary holder 8 is connected to the gear case side wall 7A via a small gap C. It is to arrange.

Thus, the other end of the planetary gear shaft 5 of the plurality of planetary gears 4 whose one end is supported by the holder 6 can be supported by the auxiliary holder 8, and all the planetary gear shafts 5 are supported at both ends to prevent the shaft from falling down. Thus, it is possible to manage the small gap C between the side wall 7A. The second concrete means for solving the problem in the present invention is the input shaft 1
A plurality of first planetary gears 4 are meshed with a first sun gear 2 and an output ring gear 3 provided on a first planetary gear 1, and one ends of first planetary gear shafts 5 supporting the respective first planetary gears 4 are connected to each other by a holder 6. A second planetary gear shaft that meshes with a second sun gear 12 in a floating state on the inner peripheral side of the second planetary gear 6, meshes a plurality of second planetary gears 13 with the second sun gear 12 and the ring gear 3, and supports each second planetary gear 13. 14 is attached to the fixing member 15, and the side wall 7A of the gear case 7 which covers them and is integrated with the ring gear 3 is arranged close to the first planetary gear shaft 5. Auxiliary holder 8 is arranged via C, and the other end of all planetary gear shafts 5 is formed to have a small diameter, and auxiliary holder 8 is fitted and fixed. And it is that it is.

As a result, the other ends of the first planetary gear shafts 5 of the plurality of first planetary gears 4 whose one ends are supported by the holder 6 can be supported by fitting and fixing the auxiliary holder 8, and the plurality of first planetary gear shafts can be supported. The support 5 can be supported at both ends to prevent the shaft from tipping over and the like, and the axial movement of the first planetary gear 4 can be restricted, so that the small gap C between the first planetary gear 4 and the side wall 7A can be managed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a planetary gear transmission that is provided as a drive mechanism of a crawler traveling device of a backhoe. The crawler sprocket 21 is driven at a reduced speed.

The hydraulic motor 20 has an axial plunger type motor body 22 disposed in a motor case (fixing member) 15 fixed to a traveling frame of a backhoe.
The control valve 23 is attached to one end of the motor case 15, and the planetary gear transmission 1 is arranged at the other end.
The motor body 22 includes a valve plate 24 having two half-moon ports, and a cylinder block 2 having a piston therein.
5. Output shaft 2 that rotates integrally with cylinder block 25
6 and a swash plate 27. The motor body 22 may be of a variable displacement type or a fixed displacement type.

The planetary gear transmission 1 has a two-stage speed reduction structure, and has an input shaft 11 directly connected to an output shaft 26 of the hydraulic motor 20 and a first shaft provided integrally with the input shaft 11.
A sun gear 2, a ring gear 3 integrally formed on the inner peripheral surface of the gear case 7, a plurality of first planetary gears 4 meshing with the first sun gear 2 and the ring gear 3, and a first supporting the first planetary gear 4. A planetary gear shaft 5;
Holder 6 supporting one end of all first planetary gear shafts 5
, An auxiliary holder 8 that supports the other end of the entire first planetary gear shaft 5, a second sun gear 12 meshed with the inner peripheral side of the holder 6, and meshes with the second sun gear 12 and the ring gear 3. And a plurality of second planetary gears 13.

Although the first sun gear 2 is formed integrally with the input shaft 11, it may be formed separately and attached. The first planetary gear 4 and the first planetary gear shaft 5 may be two sets, but usually three sets. The first planetary gear 4 meshes with the first sun gear 2 and the ring gear 3 at the same time. One end of each first planetary gear shaft 5 is press-fitted into a holder 6 and fixed by a roll pin or the like, whereby the plurality of first planetary gear shafts 5 are connected to each other by the holder 6 and the mutual relationship is fixed, and the cantilever is fixed. Will be supported.

At the same time, each first planetary gear shaft 5
Is formed with a small-diameter portion 5A, and the auxiliary holder 8 is fitted to the small-diameter portion 5A of the entire first planetary gear shaft 5 in an intermediate or shrink-fit state. The planetary gear shafts 5 are connected to each other by the auxiliary holder 8, the mutual relation is fixed, and the cantilever is supported.
Is sandwiched and supported by the holder 6 and the auxiliary holder 8.

The holder 6 and the auxiliary holder 8 are formed in a circular plate or a substantially triangular plate. Internal teeth are formed on the inner periphery of the holder 6, and the inner periphery of the auxiliary holder 8 is connected to the tip of the input shaft 11. A hole 8A for avoiding interference is formed. Since the small-diameter portion 5A of the first planetary gear shaft 5 is press-fitted into the auxiliary holder 8, the position of the needle bearing and the like between the first planetary gear 4 and the first planetary gear shaft 5 can be regulated by the auxiliary holder 8. A conventional position regulating member such as a snap ring can be omitted.

The second sun gear 1 is provided on the inner peripheral side inner teeth of the holder 6.
2, the second sun gear 12 is connected to the input shaft 1
It is arranged on the outer periphery of the device 1 via a gap, and is provided in a floating state by meshing with the holder 6. This second
A plurality of second planetary gears 13 meshing with the sun gear 12 and the ring gear 3 are provided. The second planetary gear shaft 14 of each second planetary gear 13 is
It is screwed and fixed to a motor case 15 as a fixing member.

The gear case 7 covers the first sun gear 2, the first planetary gear 4, the second planetary gear 13, and the like, and is rotatably fitted to an outer peripheral portion of the motor case 15 via a bearing 28. It has a flange portion 7B to which the sprocket 21 is attached, and the side of the first planetary gear 4 is closed with a lid to form a side wall portion 7A. The auxiliary holder 8 is located between the side wall 7A and the first planetary gear 4, and has a small gap C so as not to slide on the side wall 7A. The size of the small gap C can be appropriately set by adjusting the thickness of the auxiliary holder 8.

Although the ring gear 3 is integrally formed on the inner peripheral surface of the gear case 7, it may be formed separately and attached. These are output members and are driven by power transmitted from the second planetary gear 13. Is done. Also,
The torque from the first planetary gear 4 is also transmitted to the gear case 7. Note that the present invention is not limited to the above embodiment, and can be variously modified. For example, the planetary gear transmission 1 may be used for a drive mechanism of a working machine other than the backhoe, or may be connected to a swing motor of the backhoe.
A one-stage speed reducer without the second sun gear 12, the second planetary gear 13, a speed reducer for taking out power from the holder 6,
Alternatively, the present invention can be applied to a speed increasing device for fixing the gear case 7 or the holder 6 side.

[0017]

According to the present invention described above, the planetary gear shafts 5 of the plurality of planetary gears 4 can be connected not only by the holder 6 at one end but also by the auxiliary holder 8 at the other end. The shaft 5 can be supported at both ends to prevent the shaft from falling down, the auxiliary holder 8 can be separated from the side wall 7A, and the small gap C can be managed.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view of a holder, an auxiliary holder, and a side wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Planetary gear transmission 2 First sun gear 3 Ring gear 4 First planetary gear 5 First planetary gear shaft 6 Holder 7 Gear case 7A Side wall 8 Auxiliary holder

Claims (2)

[Claims] A plurality of planetary gears (4) mesh with a sun gear (2) and a ring gear (3), and one end of a planetary gear shaft (5) supporting each planetary gear (4) is connected to each other by a holder (6). The side wall (7A) of the gear case (7) that covers them is connected to the planetary gear shaft (5).
, The other ends of the plurality of planetary gear shafts (5) are connected to each other by an auxiliary holder (8), and the auxiliary holder (8) is connected to the gear case side wall (7A) with a small gap (C). A planetary gear transmission, wherein the planetary gear transmission is disposed through the transmission. 2. A plurality of first planetary gears (4) mesh with a first sun gear (2) and an output ring gear (3) provided on an input shaft (11), and each first planetary gear (4).
One end of a first planetary gear shaft (5) supporting the first sun gear (5) is connected to each other by a holder (6), and a second sun gear (12) in a floating state is meshed with an inner peripheral side of the holder (6). A plurality of second planetary gears (13) are engaged with the ring gear (12) and the ring gear (3), and a second planetary gear shaft (14) supporting each second planetary gear (13) is attached to a fixing member (15). Gear case (7) covered and integrated with ring gear (3)
A planetary gear transmission in which a side wall (7A) is disposed close to the first planetary gear shaft (5), wherein an auxiliary holder (8) is disposed through a small gap (C) with the gear case side wall (7A); A planetary gear transmission, characterized in that the other end of the entire planetary gear shaft (5) is formed to have a small diameter and the auxiliary holder (8) is fitted and fixed.