Camshaft adjuster

Patent metadata

Field	Value
Publication number	US-9856759-B2
Application number	US-201314430827-A
Country	US
Kind code	B2
Filing date	Sep 9, 2013
Priority date	Dec 7, 2012
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A camshaft adjuster has multiple locking guide slots and multiple locking pins spring-loaded in the direction of engagement with the locking guide slots and which, by varying assignment to the rotor and to the stator, are arranged relative to one another such that the rotor can, under the action of fluctuating torques, be automatically locked into the predetermined center position relative to the stator proceeding from a first early or late stop position by a successive engagement of the locking pins into the locking guide slots. The locking pins and the locking guide slots are arranged so that, in the event of a rotation of the rotor in the direction of the center locking position proceeding from the respective other second early or late stop position, the locking pins lock into the locking guide slots in the reverse sequence from different directions.

First claim

What is claimed is:

1. A camshaft adjuster comprising:
a stator and a rotor, the rotor being rotation angle adjustable in the stator between an advance stop position and a retard stop position, the rotor being actuated with the aid of a pressure medium;
a locking device for locking the rotor with respect to the stator in a predetermined central locking position between the advance and retard stop positions, the locking device including multiple locking gates and multiple locking pins each being spring-loaded in an engagement direction to a corresponding one of the locking gates and moved relative to each other during a rotation of the rotor with respect to the stator, due to a variable assignment to the rotor and the stator, and are situated with respect to each other in such a way that the rotor is lockable with respect to the stator by rotation of the rotor with respect to the stator when alternating torques act upon the camshaft, the rotor being lockable with respect to the stator from the advance stop position into the predetermined central locking position by the locking pins each engaging with the corresponding locking gate in a first successive order during a rotation of the rotor such that each locking pin locks with the corresponding locking gate at a different rotational position of the rotor with respect to the stator, and the rotor being lockable with respect to the stator from the retard stop position into the predetermined central locking position by the locking pins each locking in the corresponding locking gate in a second successive order that is reverse of the first successive order during a rotation of the rotor such that each locking pin locks in the corresponding locking gate at a different rotational position of the rotor with respect to the stator.

2. The camshaft adjuster as recited in claim 1 wherein the locking gates are situated and shaped in such a way that the locking gate in which a first of the locking pins first locks or is locked during a rotation from the one of the advance or retard stop position is also the locking gate in which a last of the locking pin locks during a rotation of the rotor from the other of the advance or retard stop position into the central locking position.

3. The camshaft adjuster as recited in claim 2 wherein the locking gate in which the first locking pin locks or is locked during a rotation of the rotor in a first direction from the advance or retard stop position is shaped in such a way that the first locking pin locked therein comes to stop against the edge of the locking gate when the central locking position is reached and prevents the rotor from continuing to rotate in the first direction.

4. The camshaft adjuster as recited in claim 3 wherein the locking gate in which the last locking pin locks or is locked during a rotation of the rotor from the advance or retard stop position is situated and shaped in such a way that the locking pin locked therein blocks a rotation of the rotor in a second direction counter to the first direction.

5. The camshaft adjuster as recited in claim 1 wherein the multiple locking gates include at least three locking gates and the multiple locking pins include at least three locking pins, each of the at least three locking gates being paired with one of the at least three locking pins, and the at least three locking gates are formed by curved, ring segment-shaped recesses or indentations, a first of the at least three locking pins locking in a first of the at least three locking gates and a second of the at least three locking pins locking in a second of the at least three locking gates during a rotation of the rotor from one of the advance or retard stop positions, a circumferential distance between the first and second locking gates being identical to a circumferential distance between the first and second locking pins.

6. The camshaft adjuster as recited in claim 1 wherein a first of the pins locks in a first of the locking gates and a second of the pins locks in a second of the locking gates during a rotation of the rotor from the advance or retard stop position, the first and second locking gates being axisymmetric to each other about a middle axis.

7. The camshaft adjuster as recited in claim 1 wherein a base surface of the locking gates has at least one step in at least one edge section.

8. The camshaft adjuster as recited in claim 7 wherein a width of the step in the circumferential direction corresponds to the rotation angle of the rotor around which the latter is rotated with respect to the stator until the next locking pin locks into the adjacent locking gate.

9. The camshaft adjuster as recited in claim 7 wherein the locking gates, in which one of the locking pins first locks or is locked during a rotation of the rotor from the advance or retard stop position have one or multiple steps only on the edge section of the base surface against which the locking pin rests in the advance or retard stop position.

10. The camshaft adjuster as recited in claim 1 wherein the locking gates, in which the engaging locking pins lock after the first locking pin is locked, have at least one step on both edge sections of the base surface facing the adjacent locking gates.

11. The camshaft adjuster as recited in claim 1 wherein the locking gate in which one of the locking pins is first locked in the advance stop position and the locking gate in which one of the locking pins is first locked in the retard stop position is shaped in the manner of a circular arc, and the length of the circular arc of the locking gates are dimensioned in such a way that the locking pins guided therein are movable from the advance or retard stop position into a central locking position in which rotor is locked with respect to stator in both directions of rotation.

Assignees

• Schaeffler Technologies Ag

Inventors

• Scheidig Gerhard
• Boese Olaf
• Aum Kie Heon

Classifications

• F01L1/34409

  by torque-responsive means · CPC title

• F01L2001/34459

  Locking in multiple positions · CPC title

• F01L2250/02

  the camshaft being driven by chains · CPC title

• F01L2001/34469

  Lock movement parallel to camshaft axis · CPC title

• F01L2001/34463

  Locking position intermediate between most retarded and most advanced positions · CPC title