Camshaft adjuster having a hydraulic chamber sealing element that can be switched to and fro to achieve hydraulic freewheelingt part

Patent metadata

Field	Value
Publication number	US-9970335-B2
Application number	US-201515309370-A
Country	US
Kind code	B2
Filing date	Jan 21, 2015
Priority date	May 8, 2014
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A camshaft adjuster for an internal combustion engine of a motor vehicle, having a stator and a rotor accommodated inside the stator such that the rotor can rotate relative to said stator, wherein the rotor has at least one rotor vane, which extends in the radial direction towards an inner wall of the stator and forms a first hydraulic chamber and a second hydraulic chamber between the stator and the rotor, wherein a connection gap remains between a rotor vane end face and the inner wall of the stator and fluid-connecting the first hydraulic chamber and the second hydraulic chamber. A sealing element is guided in a radially movable manner in the rotor vane end face to and fro between a sealing position, in which the sealing element bears against the inner wall of the stator to seal off the connection gap, and a connecting position, in which the first and second hydraulic chambers are connected to each other through the connecting gap.

First claim

What is claimed is:

1. A camshaft adjuster for an internal combustion engine of a motor vehicle, the camshaft adjuster comprising:
a stator and a rotor accommodated within the stator in a rotatably supported manner, the rotor including at least one rotor vane extending in a radial direction to an inner wall of the stator and forming a first hydraulic chamber and a second hydraulic chamber between the stator and the rotor, a connecting gap remaining between the rotor vane end face and the inner wall of the stator, the connecting gap fluidically connecting the first hydraulic chamber and the second hydraulic chamber; and
a sealing element radially movably guided within the rotor vane end face and switchable optionally back and forth between a sealing position, the sealing element resting against the inner wall of the stator, sealing the connecting gap, in the sealing position, and a connecting position, the first and the second hydraulic chambers being connected by the connecting gap in the connecting position.

2. The camshaft adjuster as recited in claim 1 wherein, for the purpose of switching into the sealing position, the sealing element is displaceable in the direction of the inner wall by a pressure force, applicable to the sealing element, of a hydraulic fluid, the hydraulic fluid being optionally suppliable via a control channel.

3. The camshaft adjuster as recited in claim 1 wherein the sealing element is pretensioned in the direction of the sealing position with the aid of a spring.

4. The camshaft adjuster as recited in claim 1 wherein, for the purpose of switching into the connecting position, the sealing element has at least one active surface at the inner wall of the stator, a counter-pressure force of a pressurized hydraulic fluid from the first or the second hydraulic chamber acting upon the at least one active surface.

5. The camshaft adjuster as recited in claim 4 wherein the at least one active surface is dimensioned or geometrically shaped in such a way that the sealing element is displaceable into the connecting position by the counter-pressure force acting upon the active surface during the switching into the connecting position while the rotor is rotating.

6. The camshaft adjuster as recited in claim 4 wherein a hydraulic pressure (p D ) of the hydraulic fluid optionally suppliable via a control channel is selected or fixed in such a way that the sealing element is displaceable into the sealing position against the counter-pressure force.

7. The camshaft adjuster as recited in claim 4 wherein the rotor vane end face has a rotor vane groove, the sealing element being radially displaceable by the counter-pressure force into the rotor vane groove, if the counter-pressure force is greater than the pressure force or a spring force.

8. The camshaft adjuster as recited in claim 7 wherein the rotor vane groove is fluidically connected to a control channel.

9. The camshaft adjuster as recited in claim 1 further comprising a lock, the rotor and the stator being rotatably fixedly connectable to each other with aid of the lock.

10. The camshaft adjuster as recited in claim 9 wherein the rotor is movable into a locking position when the sealing element is switched into the connecting position.

Assignees

• Schaeffler Technologies Ag

Inventors

• Boese Olaf
• Thielen Jochen

Classifications

• F01L2001/34453

  Locking means between driving and driven members · CPC title

• F01L1/3442 Primary

  using hydraulic chambers with variable volume to transmit the rotating force · CPC title

• F01L2001/34479

  Sealing of phaser devices · CPC title

• F01L1/047

  Camshafts · CPC title