Electromagnetic clutch device

Patent metadata

Field	Value
Publication number	US-9458892-B2
Application number	US-201414483842-A
Country	US
Kind code	B2
Filing date	Sep 11, 2014
Priority date	Sep 12, 2013
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

An electromagnetic clutch device includes: a meshing member; an electromagnetic coil; an armature; a cylindrical cam member; and a locking portion. The cam member is provided with a plurality of locked portions to be locked by the locking portion at different axial positions, such that the plurality of locked portions is formed adjacent to each other in a circumferential direction; the cam member rotates only by a first predetermined angle due to an axial movement of the armature from a first position to a second position, and the cam member further rotates only by a second predetermined angle due to a movement of the armature from the second position to the first position; and when locking of the locking portion is shifted from one of the plurality of locked portions to another locked portion circumferentially adjacent thereto so that the locking portion locks the another locked portion at a different axial position, the second meshing portion is meshed with the first meshing portion.

First claim

What is claimed is:

1. An electromagnetic clutch device configured to connect a first rotational member to a second rotational member in a torque transmittable manner, the electromagnetic clutch device comprising:
a meshing member including a second meshing portion to be meshed with a first meshing portion formed in the first rotational member, the meshing member being connected to the second rotational member in an axially movable but relatively non-rotatable manner;
an electromagnetic coil that causes a magnetic force by current application;
an armature that axially moves due to the magnetic force;
a cylindrical cam member that is rotatable relative to the armature and that axially moves the meshing member so that the second meshing portion is meshed with the first meshing portion; and
a locking portion provided so as to be axially immovable relative to the first rotational member and to be non-rotatable relative to the armature, wherein:
the cam member is provided with a plurality of locked portions to be locked by the locking portion at different axial positions of the cam member, such that the plurality of locked portions is formed adjacent to each other in a circumferential direction;
the cam member rotates only by a first predetermined angle due to an axial movement of the armature from a first position to a second position, and the cam member further rotates only by a second predetermined angle due to a movement of the armature from the second position to the first position; and
when locking of the locking portion is shifted from one of the plurality of locked portions to another locked portion circumferentially adjacent thereto so that the locking portion locks the another locked portion at a different axial position, the second meshing portion is meshed with the first meshing portion.

2. The electromagnetic clutch device according to claim 1 , further comprising:
a biasing member that biases the armature from the second position to the first position.

3. The electromagnetic clutch device according to claim 1 , wherein:
the armature is axially movable but non-rotatable relative to the electromagnetic coil.

4. The electromagnetic clutch device according to claim 1 , wherein:
the plurality of locked portions is formed in at least three different positions in an axial direction of the cam member; and
when the armature repeats a movement from the first position to the second position several times, the second meshing portion of the meshing member is meshed with the first meshing member of the first rotational member.

5. The electromagnetic clutch device according to claim 1 , further comprising:
a biasing member that biases the meshing member in a direction where the second meshing portion is meshed with the first meshing portion; and
a pressing mechanism including the locking portion that presses the meshing member against a biasing force of the biasing member due to an axial movement of the armature so as to axially move the meshing member, the locking portion being provided so as to be relatively non-rotatable relative to a housing that support the electromagnetic coil, wherein the cam member is cylindrical, the pressing mechanism being configured such that, in response to an axial movement of the armature, locking of the locking portion is shifted from one of the plurality of locked portions to another locked portion placed at a different axial position, wherein:
when the cam member moves to an opposite side to the meshing member in response to the axial movement of the armature, the second meshing portion is meshed with the first meshing portion due to the biasing force of the biasing member.

6. The electromagnetic clutch device according to claim 5 , wherein:
the plurality of locked portions is formed in at least three different positions in an axial direction of the cam member; and
the meshing member is configured such that, when a state where the locking portion locks a locked portion formed in a position farthest from the meshing member among the plurality of locked portions is released so that the locking portion locks a locked portion formed in a position nearest to the meshing member, the second meshing portion is meshed with the first meshing portion due to the biasing force of the biasing member.

7. The electromagnetic clutch device according to claim 5 , wherein:
in the cam member, the plurality of locked portions is formed adjacent to each other in a circumferential direction;
when the armature axially moves from a first position to a second position, the armature presses the cam member toward the meshing member so as to rotate the cam member only by a first predetermined angle; and
when the armature moves from the second position to the first position, the cam member further rotates by a second predetermined angle, so that locking of the locking portion is shifted from one of the plurality of locked portions to another locked portion adjacent thereto in the circumferential direction.

8. The electromagnetic clutch device according to claim 7 , wherein:
when the armature is placed in the first position, the locking portion abuts with an axial end surface and a circumferential side surface of the locked portion, and the pressing projection of the armature is opposed to the axial end surface in a position distanced from the side surface in the circumferential direction of the cam member; and
when the armature moves to the second position, the cam member rotates by the first predetermined angle, so that the pressing projection abuts with the side surface and the locking portion is opposed to an axial end surface of the another locked portion.

9. The electromagnetic clutch device according to claim 5 , wherein:
the second meshing portion of the meshing member is always meshed with the first meshing member; and
when the meshing member axially moves, the second meshing portion is also meshed with the second rotational member, so that the first rotational member is connected to the second rotational member in a torque transmittable manner.

10. The electromagnetic clutch device according to claim 5 , wherein:
the pressing mechanism includes a locking portion provided so as to be axially immovable relative to the second rotational member and to be non-rotatable relative to the armature; and
in a course of shifting from an uncoupled state to a coupled state along with an axial movement of the cam member due to an axial movement of the armature, a friction torque is caused so as to synchronize a rotation of the first rotational member with a rotation of the second rotational member.

11. The electromagnetic clutch device according to claim 10 , wherein:
the friction torque is caused when a second friction surface on a first-rotational-member side is axially pressed against a first friction surface on a second-rotational-member side due to the axial movement of the cam member.

12. The electromagnetic clutch device according to claim 11 , wherein:
the armature performs a pressing operation to press the cam member toward the meshing member before the locking portion locks the another locked portion; and
the second friction surface is pressed against the first friction surface due to the pressing operation.

13. The electromagnetic clutch device according to claim 12 , wherein:
the second friction surface is formed in a friction member axially movable relative to the second rotational member; and
the friction member receives a pressing force toward the second rotational member via an engage and disengage member to be elastically engaged with the meshing member within a predetermined range where the second meshing

Assignees

• Jtekt Corp

Inventors

• Fujii Noriyuki
• Suzuki Kunihiko
• Takuno Hiroshi

Classifications

• F16D2011/006

  Locking or detent means, i.e. means to keep the clutch in engaged condition · CPC title

• F16D11/14 Primary

  with clutching members movable only axially (F16D11/02, F16D11/08 take precedence) · CPC title

• F16D2011/008

  characterised by the form of the teeth forming the inter-engaging parts; Details of shape or structure of these teeth · CPC title

• F16D23/06

  and a blocking mechanism preventing the engagement of the main clutch prior to synchronisation · CPC title

• F16D2011/002

  using an external and axially slidable sleeve for coupling the teeth of both coupling components together · CPC title