JP2012137172A - Hydraulic drive reduction gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic drive reduction gear achieving reduction in a power loss by suppressing inclination of a rotational axis of a planetary gear in a radial direction and in a thrust direction in a 3K mechanical paradox planetary gear reduction mechanism.SOLUTION: The hydraulic drive reduction gear 10 includes a hydraulic motor part 11 and a reducer part 12. The reducer part 12 is rotatably attached by bearings 15A and 15B fixed to outer circumferential faces 14A and 14B of a casing 13. A plurality of planetary gears 19 are disposed around a sun gear 17 to mesh with both of the sun gear 17 and an internal gear 21 and mesh with both of the sun gear 17 and an internal gear 24. In thrust plates 25A and 25B disposed on both end faces of the sun gear 17 and the planetary gear 19, a plurality of holes equally arranged on the center and a circumference are formed in the same number and at the same pitch as those of the planetary gears.

Description

  The present invention relates to a hydraulically driven reduction gear using a 3K type mysterious planetary gear mechanism that is small and has a large reduction ratio.

  There exists patent document 1 as a prior art. Patent Document 1 uses a roller for each gear rotation shaft of the sun gear and the planetary gear so that the center distance between the sun gear and the planetary gear does not approach, thereby reducing the power loss in the 3K-type wonder planetary gear mechanism. The reduction gear is designed to achieve this.

JP 2007-255517 A

  The 3K-type wonder planetary gear mechanism can achieve a higher output torque because it has a higher reduction ratio than the conventional general planetary gear mechanism, but has a problem of large power loss. In Patent Literature 1, a roller is used for each gear rotation shaft of the sun gear and the planetary gear so that the center distance between the sun gear and the planetary gear is not close, thereby reducing power loss in the 3K-type wonder planetary gear mechanism. The reduction gear is designed to achieve this. In other words, by restricting the movement of the planetary gear rotation shaft in the radial direction, the power loss generated when the planetary gear rotation shaft is inclined in the radial direction is reduced. However, since the movement of the planetary gear rotation shaft in the thrust direction is not restricted, the power loss that occurs when the planetary gear rotation shaft tilts in the thrust direction cannot be reduced.

  The present invention has been made to solve such a problem, and is generated when the planetary gear rotation shaft is inclined in the radial direction and the thrust direction by restricting the movement of the planetary gear rotation shaft in the radial direction and the thrust direction. It is an object of the present invention to provide a hydraulically driven reduction gear using a 3K-type wonder planetary gear mechanism that can reduce power loss.

In order to solve the above-mentioned problem, the invention according to claim 1
A hydraulic motor section;
A reduction gear part of a 3K type planetary gear reduction mechanism that is rotatably supported by a casing of the hydraulic motor part via a bearing and is coupled to a shaft of the hydraulic motor part;
In the hydraulic drive speed reduction device provided with
The reduction gear unit is a sun gear driven by an output shaft of the hydraulic motor unit;
A plurality of the gears arranged around the sun gear are arranged so as to mesh with both the sun gear and the internal gear unit integrated with the casing, and are integrated with the sun gear and the main body of the speed reducer unit. A planetary gear meshing with both internal gears,
Thrust plates provided on both end faces of the sun gear and the planetary gear and arranged so as to slide with the end faces of the sun gear and the planetary gear when the sun gear and the planetary gear are displaced in the rotation axis direction. When,
Provided,
The thrust plate includes a plurality of holes arranged at equal intervals on the center and the circumference of the thrust plate, and the holes arranged at a plurality of equal intervals have the same number and the same pitch as the number of planetary gears. A central axis of the sun gear is inserted into the central hole, and a cylindrical convex portion provided on the end face of the planetary gear is inserted into the holes arranged in a plurality of positions, and the radial gear of the planetary gear is inserted. By restricting the movement in the direction, the rotation axis of the planetary gear is prevented from being inclined in the radial direction.

  According to a second aspect of the present invention, the thrust plate is arranged with little gap in the direction of the planetary gear rotation axis, and the movement of the planetary gear in the thrust direction is restricted, so that the rotation axis of the planetary gear moves in the thrust direction. It is characterized by suppressing tilting.

  The present invention regulates not only the radial direction of the planetary gear rotation shaft but also the movement in the thrust direction, thereby enabling reduction of power loss caused by the planetary gear rotation shaft tilting in the radial direction and the thrust direction. It becomes a hydraulic drive speed reducer using a 3K type mysterious planetary gear mechanism.

1 is a schematic longitudinal sectional view showing a schematic structure of a hydraulic drive speed reducing device according to an embodiment of the present invention.

An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic longitudinal sectional view showing a schematic structure of a hydraulic drive speed reduction device 10 (hereinafter referred to as a hydraulic drive speed reduction device 10) using a 3K-type wonder planetary gear mechanism according to an embodiment of the present invention.
The hydraulic drive reduction device 10 includes a fixed swash plate type axial piston type hydraulic motor unit 11 (hereinafter referred to as a hydraulic motor unit 11), and a 3K type mysterious planetary gear reduction mechanism that is rotatably coupled to the hydraulic motor unit 11. And a reduction gear unit 12. The reduction gear unit 12 is rotatably supported by bearings 15A and 15B fixed to the outer peripheral surfaces 14A and 14B of the casing 13 of the hydraulic motor unit 11, and is attached so as not to move in the axial direction.

  The shaft 16 of the hydraulic motor unit 11 is coupled in the rotational direction by a sun gear 17 and a spline unit 18. A plurality of planetary gears 19 are arranged equally on the circumference around the sun gear 17 (only two are shown in FIG. 1), and a plurality of pins 20 arranged on the sun gear 17 and the casing 13 (see FIG. 1). 1, only two are shown) are arranged so as to mesh with both of the internal gears (first internal gears) 21, and a plurality of pins 23 arranged on the sun gear 17 and the main body 22. It arrange | positions so that it may mesh | engage both with the internal gear (2nd internal gear) 24 fastened by (only 2 are displayed in FIG. 1).

The thrust plates 25A and 25B have holes 26A and 26B in the center, and a plurality of holes 28A and 28B arranged at equal intervals on the circumference around the holes 26A and 26B.
A plurality of holes 28A and 28B arranged at equal intervals on the circumference of the thrust plates 25A and 25B have the same number and the same pitch as the planetary gears 19.

The thrust plate 25A has a hole portion 26A in which the spline portion 18 of the shaft 16 is inserted into a hole portion 26A that is slightly larger than the outer diameter of the spline portion 18, and a hole portion that is slightly larger than the outer diameter of the cylindrical convex portion 27A on the end face of the planetary gear 19. A cylindrical convex portion 27A is inserted into 28A.
Similarly, in the thrust plate 25B, the spline portion 18 of the shaft 16 is inserted into the hole portion 26B that is slightly larger than the outer diameter of the spline portion 18, and the outer diameter of the cylindrical convex portion 27B on the end face of the planetary gear 19 is slightly larger. A cylindrical protrusion 27B is inserted into the hole 28B.
Further, the planetary gear 19 and the thrust plates 25A and 25B are arranged between the cover 29 and the casing 13 with almost no gap.

Although the number of teeth of the internal gear 21 and the internal gear 24 is different, the sun gear 17, the planetary gear 19, the internal gear 21 and the internal gear 24 are transition gears. The distance between the center axis of the internal gear 21 and the center axis of the internal gear 24 coincides with the center axis of the internal gear 21, and the internal gear 21 and the internal gear 24 are in relation to the planetary gear 19. Each of these meshes with each other to form a mysterious gear mechanism.
The reduction gear unit 12 is a 3K-type wonder planet, in which the three basic elements of the input shaft, the output shaft, and the fixed shaft of the planetary gear mechanism are composed of the sun gear 17, the internal gear 21, and the internal gear 24, respectively. It is a gear mechanism (K is a basic element of a planetary gear mechanism and means a gear).
With this configuration, the movement of the planetary gear 19 in the radial direction and the thrust direction of the rotation shaft 19a is restricted, and the rotation shaft 19a of the planetary gear 19 is restrained from tilting in the radial direction and the thrust direction, thereby reducing power loss. This is a hydraulic drive speed reduction device that enables the above.

  The hydraulic drive speed reduction device 10 of the present invention is basically configured as described above. Next, the operation will be described with reference to FIG. When the shaft 16 of the hydraulic motor unit 11 rotates clockwise (in the direction of arrow A in FIG. 1, the same applies hereinafter), the sun gear 17 coupled to the shaft 16 rotates clockwise. The planetary gear 19 meshing with both the sun gear 17 and the internal gear 21 coupled to the casing 13 is counterclockwise with respect to the central axis (not shown) of the sun gear 17 (in the direction of arrow B in FIG. 1). , And so on), revolving clockwise around the sun gear 17 (planetary motion).

  Since the internal gear 24 meshed with the planetary gear 19 has a different number of teeth from the internal gear 21, when the planetary gear 19 revolves around the sun gear 17, When the number of teeth is larger, the rotation is clockwise. Conversely, when the number of teeth of the internal gear 24 is smaller than that of the internal gear portion 21, the rotation is counterclockwise. Since the main body 22 is coupled to the internal gear 24, the main body 22 rotates clockwise when the internal gear 24 rotates clockwise, and conversely when the internal gear 24 rotates counterclockwise. Rotate around.

In the planetary gear 19, the thrust plate 25 </ b> A and 25 </ b> B has the spline portion 18 of the shaft 16 inserted in the holes 26 </ b> A and 26 </ b> B that are slightly larger than the outer diameter of the spline portion 18. Since the cylindrical convex portions 27A and 27B are inserted into the holes 28A and 28B that are slightly larger than the outer diameter of the planetary gears 27B, the movement of the planetary gear 19 in the radial direction is restricted, and the planetary gear 19 moves in the radial direction. The inclination of is suppressed.
Since the planetary gear 19 is disposed between the cover 29 and the casing 13 through the thrust plates 25A and 25B with almost no gap, the movement of the planetary gear 19 in the thrust direction is restricted. The inclination of 19 in the thrust direction is suppressed.

DESCRIPTION OF SYMBOLS 10 Hydraulic drive reduction device 11 Hydraulic motor part 12 Reduction gear part 13 Casing 14A, 14B Outer peripheral surface 15A, 15B Bearing 16 Shaft 17 Sun gear 18 Spline part 19 Planetary gear 20 Pin 21 Internal gear (1st internal gear)
22 Body 23 Pin 24 Internal gear (second internal gear) 25A, 25B Thrust plate 26A, 26B Hole 27A, 27B Cylindrical convex 28A, 28B Hole

Claims (2)

A hydraulic motor section;
A reduction gear part of a 3K type planetary gear reduction mechanism that is rotatably supported by a casing of the hydraulic motor part via a bearing and is coupled to a shaft of the hydraulic motor part;
In the hydraulic drive speed reduction device provided with
The reduction gear unit is a sun gear driven by an output shaft of the hydraulic motor unit;
A plurality of the gears arranged around the sun gear are arranged so as to mesh with both the sun gear and the internal gear unit integrated with the casing, and are integrated with the sun gear and the main body of the speed reducer unit. A planetary gear meshing with both internal gears,
Thrust plates provided on both end faces of the sun gear and the planetary gear and arranged so as to slide with the end faces of the sun gear and the planetary gear when the sun gear and the planetary gear are displaced in the rotation axis direction. When,
Provided,
The thrust plate includes a plurality of holes arranged at equal intervals on the center and the circumference of the thrust plate, and the holes arranged at a plurality of equal intervals have the same number and the same pitch as the number of planetary gears. A central axis of the sun gear is inserted into the central hole, and a cylindrical convex portion provided on the end face of the planetary gear is inserted into the holes arranged in a plurality of positions, and the radial gear of the planetary gear is inserted. A hydraulically driven reduction device characterized by restraining the rotation axis of the planetary gear from being inclined in the radial direction by restricting movement in the direction. The hydraulic drive speed reducer according to claim 1,
According to a second aspect of the present invention, the thrust plate is arranged with little gap in the direction of the planetary gear rotation axis, and the movement of the planetary gear in the thrust direction is restricted, so that the rotation axis of the planetary gear moves in the thrust direction. A hydraulic drive speed reducer characterized by suppressing tilting.