Rotation mechanism

• US 8,460,145 B2
• Filed: 02/07/2008
• Issued: 06/11/2013
• Est. Priority Date: 06/11/2007
• Status: Expired due to Fees

• Current Assignee: Toyota Boshoku Kabushiki Kaisha
• Original Assignee: Toyota Boshoku Kabushiki Kaisha
• Inventors: Mitsuhashi, Atsutaka
• Primary Examiner(s): Le, David D
• Assistant Examiner(s): Christ, Steven B
• Application Number:
  US12/663,093
• Publication Number:
  US 20100180705A1
• Time in Patent Office: 1,951 Days
• Field of Search: 475/162, 475/331, 475/362, 475/344, 475/904, 297/362, 297/362.11, 297/362.12, 297/362.13, 297/362.14
• US Class Current: 475/162
• CPC Class Codes: B60N 2/2252 in which the central axis of the gearing lies inside the periphery of an orbital gear, e.g. one gear without sun gear
• CPC Class Codes: F16H 1/32 in which the central axis of the gearing lies inside the periphery of an orbital gear
• CPC Class Codes: Y10T 74/19647 Parallel axes or shafts

Abstract

Each of reclining devices is formed so as to have a different size. An external gear wheel of each of the reclining devices has a diameter smaller than an internal gear wheel thereof and has a teeth number different from the internal gear wheel. The internal gear wheels and the external gear wheels of the connection devices respectively have the same teeth number as each other. The internal gear wheels and the external gear wheels of the connection devices are formed such that distances between centers thereof are equal to each other. Further, a meshing line of the internal gear wheel and the external gear wheel of each of the connection devices is formed between two curves defining a meshing range and is drawn as a line that extends from a side of a radially inwardly positioned curve in a circumferential direction in which the two curves are gradually spaced from each other and reaches to a side of a radially outwardly positioned curve.

Claims

1. A rotation mechanism in which two connection devices relatively rotatably connecting two subject components are axially oppositely disposed such that the subject components can be coaxially rotated, each of the connection devices comprising:

an internal gear wheel connected to one of the two subject components and having inwardly-faced teeth that are formed in an inner circular circumferential surface thereof; and

an external gear wheel connected to the other of the two subject components and having outwardly-faced teeth that are formed in an outer circular circumferential surface thereof, the outwardly-faced teeth configured to mesh with the inwardly-faced teeth,

wherein the external gear wheel of each of the connection devices has a diameter smaller than a diameter of the internal gear wheel thereof and has a teeth number different from a teeth number of the internal gear wheel,

wherein relative rotational motion of the two subject components is performed by rotational displacement of the external gear wheel due to the different teeth number when the external gear wheel meshing with the internal gear wheel relatively revolves along the inwardly-faced teeth of the internal gear wheel while changing a meshing position therebetween,

wherein each of the connection devices has a different size,

wherein the internal gear wheels and the external gear wheels of the connection devices respectively have the same teeth number as each other,

wherein the internal gear wheels and the external gear wheels of the connection devices are formed such that distances between centers thereof are equal to each other,

wherein a spiral meshing line of the internal gear wheel and the external gear wheel of at least the larger of the connection devices is formed between a first addendum circle of the internal gear wheel and a second addendum circle of the external gear wheel, and

wherein the spiral meshing line is drawn as a line that is defined by a spiral of Archimedes that extends in a circumferential direction from a point on the first addendum circle of the internal gear wheel to a point on the second addendum circle of the external gear wheel, the first addendum circle and the second addendum circle being gradually spaced from each other in the circumferential direction.

2. The rotation mechanism as defined in claim 1, wherein the spiral meshing line of the internal gear wheel and the external gear wheel of each of the connection devices is formed between the first addendum circle of the internal gear wheel and the second addendum circle of the external gear wheel, and

wherein the spiral meshing line is drawn as a line that is defined by a spiral of Archimedes that extends in a circumferential direction from a point on the first addendum circle of the internal gear wheel to a point on the second addendum circle of the external gear wheel, the first addendum circle and the second addendum circle being gradually spaced from each other in the circumferential direction.

3. The rotation mechanism as defined in claim 1, wherein each of the connection devices is constructed as a reclining device that rotatably connects a seat back of a vehicle seat to a seat cushion such that a tilting angle of the seat back can be adjusted.