Clutch device and steering device

Patent metadata

Field	Value
Publication number	US-9359003-B2
Application number	US-201214437874-A
Country	US
Kind code	B2
Filing date	Nov 5, 2012
Priority date	Nov 5, 2012
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A clutch apparatus is configured such that a first mode, a second mode and a third can be switched among these three modes. In the first mode, the rotating force is not transmitted between the steering-wheel-side housing and the tire-side housing. In the second mode, the steering-wheel-side housing and the tire-side housing are being mutually locked in place and, in this locked state, the rotating force can be transmitted to for the rotation in the both directions. In the third mode, the transmission of the rotating force can be canceled such that while the rotating force can be transmitted, between the steering-wheel-side housing and the tire-side housing, relative to the rotation in one direction, the rotation of either the steering-wheel-side housing or the tire-side housing in the other direction is allowed.

First claim

What is claimed is:

1. A clutch apparatus for switching transmission and cutoff of a rotating force between two rotating shafts, the clutch apparatus comprising:
a first rotating shaft formed circumferentially such that a plurality of grooves are formed mutually at intervals in an inner or outer circumference;
a second rotating shaft arranged such that the second rotating shaft is placed coaxially with the first rotating shaft and such that at least part of the second rotating shaft overlaps with the first rotating shaft;
a plurality of engagement portions arranged in a circumferential direction of the second rotating shaft such that the plurality of engagement portions are placed mutually at intervals, the engagement portions being so provided in the second rotating shaft as to be movable in a radial direction of the second rotating shaft;
an advancing/retreating mechanism that advances and retreats the engagement portions toward and away from the grooves; and
a regulating mechanism that regulates movement of at least one of the engagement portions, when the advancing/retreating mechanism moves the plurality of engagement portions toward the grooves,
wherein the plurality of engagement portions and the plurality of grooves are so configured as to achieve a first engagement state and a second engagement state,
the first engagement state being a state of the engagement portions and the grooves where the two rotating shafts are locked with each other, with a backlash, which is less than or equal to a first predetermined amount, such that a predetermined combination of two engagement portions enter their corresponding grooves in the plurality of grooves by the advancing/retreating mechanism, whereby the rotating force is transmittable for a rotation in both directions, and
the second engagement state being a state thereof where a relative rotation having a second predetermined amount, which is greater than the first predetermined amount, is allowed between the two rotating shafts such that the advancing/retreating mechanism restricts a movement of one of the predetermined combination of two engagement portions into the groove.

2. The clutch apparatus according to claim 1 , the plurality of engagement portions including:
a first engagement portion that enters a first groove, which is any one of the plurality of grooves, regardless of a difference in rotational phases between the first rotating shaft and the second rotating shaft, when the advancing/retreating mechanism moves the plurality of engagement portions toward the plurality of grooves; and
a second engagement portion that enters a second groove, which differs from the first groove, when the first engagement portion moves in either a clockwise or counterclockwise direction with the first engagement portion having entered the first groove,
wherein the first engagement portion is configured such that, while the first engagement portion and the second engagement portion have entered their corresponding grooves, a backlash between the first engagement portion and a lateral surface, which is one of two lateral surfaces of the first groove, on one rotation direction side near the first engagement portion, is less than or equal to the first predetermined amount.

3. The clutch apparatus according to claim 1 , the plurality of engagement portions including:
a first engagement portion that enters a first groove, which is any one of the plurality of grooves regardless of a difference in rotational phases between the first rotating shaft and the second rotating shaft, when the advancing/retreating mechanism moves the plurality of engagement portions toward the grooves; and
a second engagement portion that enters a second groove, which differs from the first groove, when the first engagement portion moves in either a clockwise or counterclockwise direction, with the first engagement portion having entered the first groove, and is engaged with a lateral surface, which is one of two lateral surfaces of the first groove, on one rotation direction side,
wherein the second engagement portion is configured such that when the second engagement portion enters the second groove, the second engagement is engaged, with the backlash, which is less than or equal to the first predetermined amount, onto a lateral surface, which is one of two lateral surfaces of the second groove, on the other rotation direction side.

4. The clutch apparatus according to claim 2 , the advancing/retreating mechanism including:
an actuator driven by electricity; and
a biasing member that biases the engagement portion toward the groove,
wherein an operation of the actuator, which is turned on, causes the engagement portion to be retreated from the groove by a force, which is larger than the biasing force of the biasing member,
when the actuator is turned off, the first engagement portion enters the first groove by the biasing force of the biasing member.

5. The clutch apparatus according to claim 4 , wherein the actuator is a rotary solenoid, and
wherein the advancing/retreating mechanism further includes a conversion mechanism for converting a rotary motion of the rotary solenoid so as to advance and retreat the engagement portion.

6. The clutch apparatus according to claim 1 , wherein the engagement portions and the grooves are so provided to satisfy
P= 360/ n,
B 1≈ W +(δ×( Nx− 1)), and

δ= P/N,

where n indicates the number of grooves (the plurality n of the grooves), P indicates a pitch of the grooves, N indicates the number of engagement portions (the plurality N of the engagement portions), Nx indicates the number of engagement portions entering a plurality of the grooves, W indicates width of the engagement portion, B1 indicates width of the groove, B2 indicates a distance between the groove and a groove adjacent thereto, and δ indicates a shifted angle formed when the engagement portion is engaged into the groove.

7. A steering apparatus comprising:
an operating member rotated to steer a vehicle;
a steering actuator that enables a steering-side reaction force to be generated by generating a rotating force transmitted to the operating member;
a steering amount detector that detects information in response to a steering amount of the operating member;
a turning mechanism that turns wheels,
a turning actuator that enables the turning-side wheels to be turned by generating a rotating force transmitted to the turning mechanism,
a clutch apparatus according to claim 1 , placed between the operating member and the turning mechanism, which switches transmission and cutoff of the rotating force between the operating member and the turning mechanism; and
a control apparatus that not only performs control such that the steering-side reaction force is generated by the steering actuator in response to an input to the operating member, while the rotating force between the first rotating shaft and the second rotating shaft is being cut off by the clutch apparatus, but also controls a turning position on a turning side, based on information in response to a steering amount of the operating member,
wherein the control apparatus controls a switching such that the clutch apparatus is in the second engagement state, based on information, predicting that an output of the turning actuator required for a controlling of the turning position by the turning actuator will be deficient, or information indicating that the output thereof is actually deficient.

8. The steering apparatus according to claim 7 , further comprising a turning amount detector that detects information in response to a turning amount of the turning mechanism,
wherein the control apparatus performs control such that the clutch apparatus is switched t

Assignees

• Toyota Motor Co Ltd

Inventors

• Ito Koichi

Classifications

• F16D28/00

  Electrically-actuated clutches (arrangements for synchronisation F16D23/02; clutches actuated directly by means of an electromagnet F16D27/00; automatic clutches F16D43/00 - F16D45/00; external control F16D48/00) · CPC title

• B62D5/003 Primary

  Backup systems, e.g. for manual steering (B62D5/30 takes precedence) · CPC title

• F16D2500/50858

  Selecting a Mode of operation · CPC title

• F16D2500/5085

  Coasting · CPC title

• F16D2023/123

  Clutch actuation by cams, ramps or ball-screw mechanisms · CPC title