Power Transmission System for Vehicle and Manufacturing Method for the Same

• US 20170314659A1
• Filed: 04/21/2017
• Published: 11/02/2017
• Est. Priority Date: 04/28/2016
• Status: Abandoned Application

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: MICHIKOSHI, Yosuke, IKEMURA, Masashi
• Application Number:
  US15/494,117
• Publication Number:
  US 20170314659A1
• Time in Patent Office: Days
• CPC Class Codes: F16D 1/0835 due to the elasticity of the ring or sleeve
• CPC Class Codes: F16D 7/021 with radially applied torque-limiting friction surfaces F16D7/022 takes precedence
• CPC Class Codes: F16H 2200/006 the gear ratios comprising eight forward speeds
• CPC Class Codes: F16H 2200/2007 with two sets of orbital gears
• CPC Class Codes: F16H 2200/201 with three sets of orbital gears
• CPC Class Codes: F16H 2200/2023 using a Ravigneaux set with 4 connections
• CPC Class Codes: F16H 2200/2046 with six engaging means
• CPC Class Codes: F16H 2200/2066 using one freewheel mechanism
• CPC Class Codes: F16H 2200/2082 one freewheel mechanisms
• CPC Class Codes: F16H 2200/2097 comprising an orbital gear set member permanently connected to the housing, e.g. a sun wheel permanently connected to the housing
• CPC Class Codes: F16H 3/663 with conveying rotary motion between axially spaced orbital gears, e.g. RAVIGNEAUX
• CPC Class Codes: F16H 3/666 with compound planetary gear units, e.g. two intermeshing orbital gears F16H3/663 takes precedence
• CPC Class Codes: F16H 35/10 Arrangements or devices for absorbing overload or preventing damage by overload for screw mechanisms F16H25/2021
• CPC Class Codes: F16H 57/0037 Special features of coaxial shafts, e.g. relative support thereof
• CPC Class Codes: F16H 57/08 of gearings with members having orbital motion

Abstract

A tolerance ring is formed in an inner circumference of a clutch drum at a more forward position than a spline-fitted part in a forward direction during assembly of the clutch drum to a third sun gear; thus, the tolerance ring is located closer to an axial end of the clutch drum than to the spline-fitted part. Accordingly, it becomes easier to carry out grooving to form an annular groove for housing the tolerance ring therein in the inner circumference of the clutch drum, and thereby deterioration of machinability is suppressed.

Claims

1. A manufacturing method for a power transmission system for a vehicle,

the vehicle including:

a first rotary body configured to rotate around an axial line;

a second rotary body including a fitting hole into which one end portion of the first rotary body is fitted, the second rotary body being configured to rotate around the axial line; and

a spline-fitted part configured such that external circumferential teeth provided on an outer circumferential surface of the first rotary body and internal circumferential teeth provided on an inner circumferential surface of the fitting hole are spline-fitted to each other,

the manufacturing method comprising;

disposing a tolerance ring in an annular groove that is provided in an inner circumference of the second rotary body and is disposed at a more forward position than the spline-fitted part in a forward direction while the second rotary body is assembled to the first rotary body when the first rotary body and the second rotary body are fitted to each other; and

assembling the first rotary body and the second rotary body to each other in such a manner as to bring the tolerance ring to come into contact with both the first rotary body and the second rotary body.

2. The manufacturing method according to claim 1, wherein

a diameter of the first rotary body located at a more backward position than the external circumferential teeth in the forward direction while the first rotary body is assembled to the second rotary body is equal to or larger than a diameter of a bottom of the external circumferential teeth of the first rotary body.

3. The manufacturing method according to claim 1, wherein

the power transmission system for the vehicle includes:

a first planetary gear unit;

a second planetary gear unit; and

a third planetary gear unit, the first planetary gear unit, the second planetary gear unit, and the third planetary gear unit being configured to rotate around the axial line that is common to the first planetary gear unit, the second planetary gear unit, and the third planetary gear unit,

the second planetary gear unit and the third planetary gear unit are configured to be of a ravigneaux planetary gear unit in which a carrier of the second planetary gear unit and a carrier of the third planetary gear unit are configured as a common member and a ring gear of the second planetary gear unit and a ring gear of the third planetary gear unit are configured as a common member,

a clutch is provided between the ring gear of the first planetary gear unit and a sun gear of the third planetary gear unit,

the spline-fitted part is provided between the sun gear and a clutch drum of the clutch,

the first rotary body is the sun gear, and

the second rotary body is the clutch drum.

4. The manufacturing method according to claim 1, wherein

a wall thickness of a portion of the second rotary body where the annular groove is disposed is thicker than a wall thickness of a portion of the first rotary body where the external circumferential teeth are disposed.

5. A power transmission system for a vehicle, the power transmission system comprising:

a first rotary body configured to rotate around an axial line;

a second rotary body including a fitting hole into which one end portion of the first rotary body is fitted, the second rotary body being configured to rotate around the axial line;

a spline-fitted part configured such that external circumferential teeth provided on an outer circumferential surface of the first rotary body and internal circumferential teeth provided on an inner circumferential surface of the fitting hole are spline-fitted to each other; and

a tolerance ring provided between the outer circumferential surface of the first rotary body and an inner circumferential surface of the second rotary body,

wherein the tolerance ring is housed in an annular groove disposed in the inner circumferential surface of the second rotary body, and is located at a position closer to an opening of the fitting hole than to the spline-fitted part in an axial line direction.

6. The power transmission system for the vehicle according to claim 5, wherein

a diameter of the first rotary body located at a more backward position than the external circumferential teeth in a forward direction while the first rotary body is assembled to the second rotary body is equal to or larger than a diameter of a bottom of the external circumferential teeth of the first rotary body.

7. The power transmission system for the vehicle according to claim 5, wherein

the power transmission system for the vehicle includes:

a first planetary gear unit;

a second planetary gear unit; and

a third planetary gear unit, the first planetary gear unit, the second planetary gear unit, and the third planetary gear unit are configured to rotate around the axial line that is common to the first planetary gear unit, the second planetary gear unit, and the third planetary gear unit,

the second planetary gear unit and the third planetary gear unit are configured to be of a ravigneaux planetary gear unit in which a carrier of the second planetary gear unit and a carrier of the third planetary gear unit are configured as a common member and a ring gear of the second planetary gear unit and a ring gear of the third planetary gear unit are configured as a common member,

a clutch is provided between the ring gear of the first planetary gear unit and a sun gear of the third planetary gear unit,

the spline-fitted part is provided between the sun gear and a clutch drum of the clutch,

the first rotary body is the sun gear, and

the second rotary body is the clutch drum.

8. The power transmission system for the vehicle according to claim 5, wherein

a wall thickness of a portion of the second rotary body where the annular groove is disposed is thicker than a wall thickness of a portion of the first rotary body where the external circumferential teeth are disposed.