Transmission device

Patent metadata

Field	Value
Publication number	US-11739827-B2
Application number	US-201917640030-A
Country	US
Kind code	B2
Filing date	Sep 11, 2019
Priority date	Sep 11, 2019
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

A transmission device includes a power-transmission case having a carrier of a reduction gear and a differential case joined to the carrier is supported in a transmission case via case support bearings, a specific planetary gear portion of a planetary gear is disposed on one side of a differential mechanism in an axial direction, and the specific case support bearing is disposed on the other side thereof An oil passage-forming body is provided on an inner wall of the transmission case, the oil passage-forming body comprising an oil collection part that opens upward and can collect lubricating oil splashed up in an area around the specific planetary gear portion within the transmission case accompanying rotation of the power-transmission case, and an oil reservoir part that is continuous from the oil collection part, stores lubricating oil collected by the oil collection part, and supplies the lubricating oil to the specific case support bearing.

First claim

The invention claimed is:

1. A transmission device comprising
a reduction gear having a sun gear, a ring gear that is disposed concentrically with the sun gear and is fixed to a transmission case, a plurality of planetary gears that mesh with the sun gear and the ring gear, and a carrier that rotatably supports the plurality of planetary gears via respective pivot shafts, and
a differential device having a differential case that receives rotational power from the reduction gear and a differential mechanism that is disposed within the differential case and distributes the rotational power between a pair of output shafts while allowing differential rotation,
a power-transmission case comprising the carrier and the differential case joined to the carrier being rotatably supported and housed in the transmission case at least via a pair of case support bearings,
a specific planetary gear portion of the planetary gear being disposed on one side of the differential mechanism in an axial direction, and a specific one of the case support bearings being disposed on the other side of the differential mechanism,
wherein an oil passage-forming body is provided on an inner wall of the transmission case, the oil passage-forming body comprising an oil collection part that opens upward and can collect lubricating oil splashed up in an area around the specific planetary gear portion within the transmission case accompanying rotation of the power-transmission case, and an oil reservoir part that is continuous from the oil collection part, stores lubricating oil collected by the oil collection part, and supplies the lubricating oil to the specific case support bearing.

2. The transmission device according to claim 1 , wherein the planetary gear is a two-stage planetary gear integrally having a first planetary gear portion meshing with the sun gear and a second planetary gear portion formed so as to have a smaller diameter than a diameter of the first planetary gear portion, being present at a position close to the specific case support bearing in the axial direction, and meshing with the ring gear, and
the first planetary gear portion forms the specific planetary gear portion.

3. The transmission device according to claim 2 , wherein the oil passage-forming body is formed from a gutter-shaped member that is mounted on the transmission case so as to extend through an interior of a mounting groove recessed in an inner face of the transmission case, and
a cutout-shaped recess portion is formed in an inner periphery of the transmission case so that an axial position thereof is made to coincide with an axial position of at least part of the oil collection part, the cutout-shaped recess portion guiding to an upper opening of the oil collection part lubricating oil running down along an inner peripheral face of the transmission case above the mounting groove.

4. The transmission device according to claim 3 , wherein the oil reservoir part is disposed so as to extend through a space between the ring gear and the transmission case in a radial direction.

5. The transmission device according to claim 3 , wherein the case support bearing is disposed between a bearing boss portion and an annular power-transmission case support portion, the bearing boss portion being projectingly provided on the power-transmission case and being rotatably fitted onto and supporting an outer periphery of one output shaft, and the power-transmission case support portion being projectingly provided on the transmission case and having said one output shaft extending through the interior thereof in the axial direction,
the transmission case has a cutout portion providing communication between an outer peripheral part and an inner peripheral part of the power-transmission case support portion, and
the oil passage-forming body has a downstream end reaching the cutout portion and can supply to a part where said one output shaft is fitted to the bearing boss portion lubricating oil that has flowed through the oil passage-forming body.

6. The transmission device according to claim 2 , wherein the oil reservoir part is disposed so as to extend through a space between the ring gear and the transmission case in a radial direction.

7. The transmission device according to claim 6 , wherein the case support bearing is disposed between a bearing boss portion and an annular power-transmission case support portion, the bearing boss portion being projectingly provided on the power-transmission case and being rotatably fitted onto and supporting an outer periphery of one output shaft, and the power-transmission case support portion being projectingly provided on the transmission case and having said one output shaft extending through the interior thereof in the axial direction,
the transmission case has a cutout portion providing communication between an outer peripheral part and an inner peripheral part of the power-transmission case support portion, and
the oil passage-forming body has a downstream end reaching the cutout portion and can supply to a part where said one output shaft is fitted to the bearing boss portion lubricating oil that has flowed through the oil passage-forming body.

8. The transmission device according to claim 2 , wherein the case support bearing is disposed between a bearing boss portion and an annular power-transmission case support portion, the bearing boss portion being projectingly provided on the power-transmission case and being rotatably fitted onto and supporting an outer periphery of one output shaft, and the power-transmission case support portion being projectingly provided on the transmission case and having said one output shaft extending through the interior thereof in the axial direction,
the transmission case has a cutout portion providing communication between an outer peripheral part and an inner peripheral part of the power-transmission case support portion, and
the oil passage-forming body has a downstream end reaching the cutout portion and can supply to a part where said one output shaft is fitted to the bearing boss portion lubricating oil that has flowed through the oil passage-forming body.

9. The transmission device according to claim 1 , wherein the oil collection part is disposed on an intermediate part in a peripheral direction of a semicircular part of the transmission case on one side of a vertical line passing through a rotational axis of the power-transmission case when viewed on a projection plane orthogonal to the rotational axis, and
the semicircular part of the transmission case on said one side is a semicircular part on the side on which an outer peripheral part of the power-transmission case at the time of forward rotation moves in the peripheral direction from an apex part of the transmission case to a bottom part.

10. The transmission device according to claim 1 , wherein the oil passage-forming body is formed from a gutter-shaped member that is mounted on the transmission case so as to extend through an interior of a mounting groove recessed in an inner face of the transmission case, and
a cutout-shaped recess portion is formed in an inner periphery of the transmission case so that an axial position thereof is made to coincide with an axial position of at least part of the oil collection part, the cutout-shaped recess portion guiding to an upper opening of the oil collection part lubricating oil running down along an inner peripheral face of the transmission case above the mounting groove.

11. The transmission device according to claim 10 , wherein the oil reservoir part is disposed so as to extend through a space between the ring gear and the transmission case in a radial direction.

Assignees

• Musashi Seimitsu Kogyo Kk

Inventors

• Asai Ryosuke
• Butta Naofumi

Classifications

• F16H57/0457 Primary

  Splash lubrication · CPC title

• F16H57/045

  Lubricant storage reservoirs, e.g. reservoirs in addition to a gear sump for collecting lubricant in the upper part of a gear case · CPC title

• F16H57/0409

  characterised by increasing efficiency, e.g. by reducing splash losses · CPC title

• F16H57/0424

  Lubricant guiding means in the wall of or integrated with the casing, e.g. grooves, channels, holes · CPC title

• F16H57/0479

  Gears or bearings on planet carriers · CPC title