Hydraulic camshaft adjuster having a mechanical and a hydraulic ratchet

Patent metadata

Field	Value
Publication number	US-10844756-B2
Application number	US-201816636440-A
Country	US
Kind code	B2
Filing date	Aug 1, 2018
Priority date	Aug 8, 2017
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

The disclosure relates to a hydraulic camshaft adjuster having a stator, which is synchronously rotatable with a crankshaft of the internal combustion engine, a rotor rotatably arranged relative to the stator and synchronously rotatable with a camshaft, two groups of working chambers that can each be loaded with a pressure medium in a pressure medium circuit, and a central locking device for locking the rotor in a defined position relative to the stator. The stator is delimited on a first front end by a multi-part locking cover. The multi-part locking cover has a first locking cover and a second locking cover. A first stage of a mechanical ratchet is formed on the first locking cover, and at least one further stage of the mechanical ratchet is formed on the second locking cover.

First claim

The invention claimed is:

1. A hydraulic camshaft adjuster for adjusting timing of gas exchange valves of an internal combustion engine, the hydraulic camshaft adjuster comprising:
a stator configured to be synchronously rotatable with a crankshaft of the internal combustion engine,
a rotor configured to be rotatable relative to the stator and synchronously rotatable with a camshaft,
two groups of working chambers formed by the stator and rotor, the two groups of working chambers configured to be supplied a pressure medium flowing in or out in a pressure medium circuit,
a central locking device for locking the rotor in a defined position relative to the stator,
the stator delimited at a first end by a multi-part locking cover,

the multi-part locking cover having a first locking cover and a second locking cover, and
a first step of a mechanical ratchet formed on the first locking cover, and at least one second step of the mechanical ratchet formed on the second locking cover, and
a check valve plate arranged between the first locking cover and the second locking cover.

2. The hydraulic camshaft adjuster as claimed in claim 1 , wherein the second locking cover includes at least one insert configured to operatively connect with a locking pin of the central locking device.

3. The hydraulic camshaft adjuster as claimed in claim 2 , wherein a stop for the locking pin is formed on the at least one insert.

4. The hydraulic camshaft adjuster as claimed in claim 2 , wherein the at least one second step of the mechanical ratchet is formed on the at least one insert.

5. The hydraulic camshaft adjuster as claimed in claim 2 , wherein the at least one insert is composed of a harder material than a material of the second locking cover.

6. The hydraulic camshaft adjuster as claimed in claim 5 , wherein the at least one insert is composed of a sintered metal or is produced by a fine blanking or extrusion method.

7. The hydraulic camshaft adjuster as claimed claim 2 , wherein the at least one insert is pressed into a guide slot base of the central locking device.

8. The hydraulic camshaft adjuster as claimed in claim 2 , wherein the at least one insert is secured against tilting or falling out by the check valve plate.

9. A hydraulic camshaft adjuster for adjusting timing of gas exchange valves of an internal combustion engine, the hydraulic camshaft adjuster comprising:
a stator configured to be synchronously rotatable with a crankshaft of the internal combustion engine,
a rotor configured to be rotatable relative to the stator and synchronously rotatable with a camshaft,
a central locking device for locking the rotor to the stator,
the stator delimited at a first end by a multi-part locking cover, the multi-part locking cover having a first locking cover and a second locking cover, and
a first step of a mechanical ratchet formed on the first locking cover, and at least one second step of the mechanical ratchet formed on the second locking cover, and
a check valve plate arranged between the first locking cover and the second locking cover.

10. The hydraulic camshaft adjuster as claimed in claim 9 , wherein the central locking device comprises a locking pin configured to move and stop at three different positions.

11. The hydraulic camshaft adjuster as claimed in claim 10 , wherein the locking pin is configured to move to a locked position, an intermediate position, and an unlocked position.

12. The hydraulic camshaft adjuster as claimed in claim 10 , wherein in the locked position and the intermediate position, the rotor is locked to the stator.

13. The hydraulic camshaft adjuster as claimed in claim 12 , wherein the locking pin includes a recess configured to receive a pressure medium.

14. The hydraulic camshaft adjuster as claimed in claim 13 , wherein in the unlocked position of the locking pin, the recess is configured to fluidly connect a duct arranged within the rotor to a working chamber of the hydraulic camshaft adjuster.

15. The hydraulic camshaft adjuster as claimed in claim 9 , wherein the second locking cover includes at least one insert configured to operatively connect with a locking pin of the central locking device.

16. The hydraulic camshaft adjuster as claimed in claim 15 , wherein a stop for the locking pin is formed on the at least one insert.

17. The hydraulic camshaft adjuster as claimed in claim 16 , wherein the at least one second step of the mechanical ratchet is formed on the at least one insert.

18. The hydraulic camshaft adjuster as claimed in claim 15 , wherein the first locking cover is arranged to engage the rotor.

19. The hydraulic camshaft adjuster as claimed in claim 16 , wherein the first locking cover includes an aperture configured to receive pressure medium to move the locking pin.

20. The hydraulic camshaft adjuster as claimed in claim 15 , wherein the check valve plate secures the at least one insert within the second locking cover.

Assignees

• Schaeffler Technologies Ag

Inventors

• Thielen Jochen
• Keck Michael
• Schmitt Enno

Classifications

• F01L2001/34479

  Sealing of phaser devices · CPC title

• F01L2001/34453

  Locking means between driving and driven members · CPC title

• F01L2001/34469

  Lock movement parallel to camshaft axis · CPC title

• F01L1/3442 Primary

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

• F01L2001/34466

  with multiple locking devices · CPC title