CAMSHAFT PHASER INCLUDING LOCKING PART OR ROTOR HAVING GROOVE
A camshaft phaser includes for an internal combustion engine includes a stator, a rotor rotatable with respect to the stator, a locking cover non-rotatably fixed to the stator and a locking assembly including a locking part configured for engaging with the locking cover to selectively lock the rotor with respect to the stator. The locking part is configured for being movable via hydraulic fluid in a hole in the rotor. The locking part or a surface of the hole including a groove configured for receiving contaminant particles in the hydraulic fluid.
The present disclosure relates generally to camshaft phasers and more specifically to locking pins for camshaft phasers.
BACKGROUNDCamshaft phasers can include a rotor movable with respect to a stator by fluid and a locking pin for fixing the rotor with respect to the stator.
SUMMARY OF THE INVENTIONA camshaft phaser includes a stator, a rotor rotatable with respect to the stator, a locking cover non-rotatably fixed to the stator and a locking assembly including a locking part configured for engaging with the locking cover to selectively lock the rotor with respect to the stator. The locking part is configured for being movable via hydraulic fluid in a hole in the rotor. The locking part or a surface of the hole including a groove configured for receiving contaminant particles in the hydraulic fluid.
In embodiments of the camshaft phaser, the groove may be in an outer circumferential surface of the locking part. The groove may be an annular groove extending continuously in the outer circumferential surface. The locking assembly may include a spring axially biasing the locking part. The spring may be configured for forcing the locking part into the locking cover in a locking orientation of the locking assembly and the camshaft phaser may be configured such that the hydraulic fluid compresses the spring to hold the spring axially away from the locking cover in an unlocking orientation of the locking assembly. The locking assembly may include a base and the spring may be sandwiched axially between the base and the locking part. The locking part may include an end section configured for abutting the locking cover and a cylindrical section delimiting a blind hole receiving a portion of the spring. The groove may be formed in the cylindrical section. The locking assembly may be configured such that an outer circumferential surface of locking part is slidable axially along the surface of the hole in the rotor. An axial contact surface of the locking part may be configured for contacting an axial contact surface of the locking cover. The groove may be spaced from the axial contact surface of the locking part such that the groove is radially aligned with the surface of the hole in the rotor through an entire axial movement path of the locking part.
A method of constructing a camshaft phaser is also provided. The method includes providing a stator and a rotor rotatable inside the stator; non-rotatably fixing a locking cover to the stator; and providing a locking assembly including a locking part configured for engaging with the locking cover to selectively lock the rotor with respect to the stator. The locking part is configured for being movable via hydraulic fluid in a hole in the rotor. The locking part or a surface of the hole including a groove configured for receiving contaminant particles in the hydraulic fluid.
In embodiments of the method, the providing of the locking assembly may include inserting the locking assembly into the hole in the rotor. The providing of the locking assembly may include fixing a bushing of the locking cover over the hole in the rotor after the inserting of the locking assembly into a hole in the rotor. The locking assembly may be configured for axially forcing the locking part against the bushing in a locking orientation of the locking assembly. The locking assembly is inserted in the hole such that an outer circumferential surface of locking part is slidable axially along the surface of the hole in the rotor. The locking assembly may be inserted in the hole such that an axial contact surface of the locking part is configured for contacting an axial contact surface of the locking cover and the groove is spaced from the axial contact surface of the locking part such that the groove is radially aligned with the surface of the hole in the rotor through an entire axial movement path of the locking part. The method may further include forming the groove in an outer circumferential surface of the locking part. The locking part may include an end section configured for abutting the locking cover and a cylindrical section delimiting a blind hole receiving a portion of the spring. The forming of the groove in the outer circumferential surface of the locking part may include forming the groove in the cylindrical section. The providing of the locking assembly may include arranging a spring of the locking assembly axially between a base of the locking assembly and the locking part such that the spring axially biases the locking part away from the base.
The present invention is described below by reference to the following drawings, in which:
The present disclosure provides a camshaft phaser including a locking pin or rotor configured to prevent contaminants from getting stuck inside the locking assembly.
In a known manner, annular section 22 may include a plurality of circumferentially spaced lobes that protrude radially inward further than outermost sections of inner circumferential surface 24. Rotor 14 includes a plurality of circumferentially spaced vanes 26 protruding radially outward from a center section 28 of rotor 14.
Cover plate 20 is positioned on a first axial side of rotor 14, and the locking cover 18 is positioned on a second axial side of rotor 14. Stator 16, locking cover 18 and cover plate 20 are fixed together by a plurality of fasteners 31 passing through annular section 22, locking cover 18 and cover plate 20, with the fasteners 31 passing through the lobes of annular section 22.
Camshaft phaser 10 further includes a locking assembly 32 that includes a base 34, a coil spring 36 and an axially movable locking part 38.
Locking base 34 includes a support section 42 configured for fixing base 34 axially in place in rotor 14 and a pin-shaped axial protrusion 44 extending axially from support section 42. Support section 42 is radially wider than protrusion 44 and includes a radially outwardly extending collar 42a for engaging with an edge 46a defined by a groove 46b formed in rotor 14 to hold base 34 axially in place in rotor 14. Protrusion 44 has a tapered outer circumferential surface 44a that forms a form fit connection with an inner circumference of first axial end 36a of spring 36.
Locking part 38 is cup shaped and includes a disk shaped end section 38a and a cylindrical section 38b extending axially from end section 38a away from locking cover 18. Cylindrical section 38b surrounds a portion of spring 36 and defines a blind hole 38c receiving the portion of spring 36. Blind hole 38c also receives a portion of axial protrusion 44. Second axial end 36b of spring 36 axially abuts an inner radially extending surface 38g of end section 38a. More specifically, locking cover 18 includes a hole 48 extending axially therethrough and a bushing 50 received in hole 48. Bushing 50 is cup shaped and includes a disk shaped end section 50a and a cylindrical section 50b extending axially from end section 50a toward rotor 14. Cylindrical section 50b is configured for surrounding end section 38a of locking part 38 and defines a blind hole 50c receiving end section 38a. A rim 50g of cylindrical section 50b abuts a radially extending surface 14a of rotor 14.
In an extended orientation of locking assembly 32—i.e., a locking orientation of locking assembly 32, which is shown in
To switch locking assembly 32 from the extended orientation to the retracted orientation, fluid is forced through a channel 52 (
While locking part 38 is moved axially within hole 40, an outer circumferential surface 38e of locking part 38 slides axially along an inner circumferential surface 40a of hole 40. During such sliding, particles that may be present in the hydraulic fluid, for example metal particles via contamination from the engine oil, provided to chamber 54 may be forced between outer circumferential surface 38e of locking part 38 and inner circumferential surface 40a of hole 40. In order to prevent the particles from getting stuck between outer circumferential surface 38e and inner circumferential surface 40a in a manner that causes locking part 38 to jam, thus preventing axial movement of locking part 38, an annular groove 58 is formed in outer circumferential surface 38e. Annular groove 58 is configured to receive and retain particles that enter between outer circumferential surface 38e and inner circumferential 40a to prevent locking part 38 from getting axially stuck in place.
In an alternative embodiment shown in
In the preceding specification, the invention has been described with reference to specific exemplary embodiments and examples thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative manner rather than a restrictive sense.
LIST OF REFERENCE NUMERALS
- CA center axis
- 10 camshaft adjuster
- 12 stator assembly
- 14 rotor
- 14a radially extending surface
- 16 stator
- 17 sprocket
- 17a teeth
- 18 locking cover
- 18a radially extending inner surface
- 20 cover plate
- 20a radially extending inner surface
- 22 annular section
- 24 inner circumferential surface
- 26 vane
- 28 center section
- 28a outer circumferential surface
- 29 seal
- 30 spring
- 31 fasteners
- 32 locking assembly
- 34 base
- 34a first axial end
- 34b second axial end
- 36 coil spring
- 36a first axial end
- 36b second axial end
- 38 locking part
- 38a end section
- 38b base section
- 38c blind hole
- 38d angled surface
- 38e outer circumferential surface
- 38f axial contact surface
- 38g inner radially extending surface
- 40 hole
- 40a inner circumferential surface
- 42 support section
- 42a radially outwardly extending collar
- 44 axial protrusion
- 46a edge
- 46b groove
- 48 hole
- 50 bushing
- 50a end section
- 50b cylindrical section
- 50c blind hole
- 50d inner circumferential surface
- 50e angled edge surface
- 50f axial contact surface
- 50g rim
- 52 channel
- 54 hydraulic chamber
- 58 annular groove
- 60 curved edge
- 62 locking cover facing surface
- 62a central section
- 64 annular rim surface
- 66 curved surface
- 68a first outer circumferential surface section
- 68b second outer circumferential surface section
Claims
1: A camshaft phaser for an internal combustion engine comprising:
- a stator;
- a rotor rotatable with respect to the stator;
- a locking cover non-rotatably fixed to the stator; and
- a locking assembly including a locking part configured for engaging with the locking cover to selectively lock the rotor with respect to the stator, the locking part being configured for being movable via hydraulic fluid in a hole in the rotor, a surface of the hole including a groove configured for receiving contaminant particles in the hydraulic fluid.
2: The camshaft phaser as recited in claim 1 wherein the groove is in an inner circumferential surface of the hole.
3: The camshaft phaser as recited in claim 2 wherein the groove is an annular groove extending continuously in the inner circumferential surface.
4: The camshaft phaser as recited in claim 1 wherein the locking assembly includes a spring axially biasing the locking part.
5: The camshaft phaser as recited in claim 4 wherein the spring is configured for forcing the locking part into the locking cover in a locking orientation of the locking assembly and the camshaft phaser is configured such that the hydraulic fluid compresses the spring to hold the spring axially away from the locking cover in an unlocking orientation of the locking assembly.
6: The camshaft phaser as recited in claim 4 wherein the locking assembly includes a base, the spring being sandwiched axially between the base and the locking part.
7: The camshaft phaser as recited in claim 4 wherein the locking part includes an end section configured for abutting the locking cover and a cylindrical section delimiting a blind hole receiving a portion of the spring.
8. (canceled)
9: The camshaft phaser as recited in claim 1 wherein the locking assembly is configured such that an outer circumferential surface of locking part is slidable axially along the surface of the hole in the rotor.
10: The camshaft phaser as recited in claim 9 wherein an axial contact surface of the locking part is configured for contacting an axial contact surface of the locking cover, the groove being spaced from the axial contact surface of the locking part.
11: A method of constructing a camshaft phaser for an internal combustion engine comprising:
- providing a stator and a rotor rotatable inside the stator;
- non-rotatably fixing a locking cover to the stator; and
- providing a locking assembly including a locking part configured for engaging with the locking cover to selectively lock the rotor with respect to the stator, the locking part configured for being movable via hydraulic fluid in a hole in the rotor, a surface of the hole including a groove configured for receiving contaminant particles in the hydraulic fluid.
12: The method as recited in claim 11 wherein the providing of the locking assembly includes inserting the locking assembly into the hole in the rotor.
13: The method as recited in claim 12 wherein the providing of the locking assembly includes fixing a bushing of the locking cover over the hole in the rotor after the inserting of the locking assembly into a hole in the rotor, the locking assembly configured for axially forcing the locking part against the bushing in a locking orientation of the locking assembly.
14: The method as recited in claim 13 wherein the locking assembly is inserted in the hole such that an outer circumferential surface of locking part is slidable axially along the surface of the hole in the rotor.
15: The method as recited in claim 14 wherein the locking assembly is inserted in the hole such that an axial contact surface of the locking part is configured for contacting an axial contact surface of the locking cover and the groove is spaced from the axial contact surface of the locking part.
16: The method as recited in claim 11 further comprising forming the groove in an inner circumferential surface of the hole.
17. (canceled)
18: The method as recited in claim 11 wherein the providing of the locking assembly includes arranging a spring of the locking assembly axially between a base of the locking assembly and the locking part such that the spring axially biases the locking part away from the base.
Type: Application
Filed: Apr 11, 2019
Publication Date: Oct 15, 2020
Inventors: Alexandre Camilo (Rochester Hills, MI), Renato de Oliveira Ghiraldi (Madison Heights, MI)
Application Number: 16/381,212