CN111699303A

CN111699303A - Camshaft phaser

Info

Publication number: CN111699303A
Application number: CN201880088952.XA
Authority: CN
Inventors: 全婷
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Holding China Co Ltd
Priority date: 2018-05-04
Filing date: 2018-05-04
Publication date: 2020-09-22
Anticipated expiration: 2038-05-04
Also published as: CN111699303B; WO2019210510A1

Abstract

A camshaft phaser comprises a rotor (2), a stator (3) and a lock assembly (1), the rotor (2) being rotatable relative to the stator (3), the lock assembly (1) being mounted to the rotor (2) so as to be able to lock the relative rotation between the rotor (2) and the stator (3). The locking assembly (1) comprises: an elastic member mounted in the mounting hole (21h1) of the rotor, a central axis of the elastic member extending substantially in the radial direction of the rotor (2) such that the elastic member can be compressed and extended in the radial direction of the rotor (2) and a radially inner end of the elastic member is pressed against the rotor (2); and the locking pin (13) is arranged in the mounting hole (21h1) of the rotor (2), and the radial outer end of the elastic piece is pressed against the locking pin (13), so that the locking pin (13) can move towards the radial outer side under the action of the elastic force of the elastic piece to be clamped with the stator (3) to lock. The camshaft phaser is simple in structure with the locking assembly (1), and the locking clearance of the locking assembly (1) does not need to be assembled and adjusted.

Description

Camshaft phaser

Technical Field

The invention relates to a camshaft phaser.

Background

A variable valve timing system is an important component for ensuring engine performance, and is capable of adjusting the opening and closing of valves of an engine as needed so that the engine obtains a desired power output.

In the prior art, a variable valve timing system mainly includes a camshaft phaser and a camshaft connected to the camshaft phaser, which is connected to a valve of an engine through a link mechanism. Generally, a plurality of oil chambers are formed in a camshaft phaser by an end cover, a rotor and a stator (the stator and the end cover are relatively fixed), hydraulic oil with different pressures can be input into the oil chambers to enable the rotor to rotate relative to the stator and the end cover, and therefore the rotor drives the camshaft to adjust the opening and closing of an air valve. Because the rotor is required to be unable to rotate relative to the stator when the variable valve timing system is not required to function, a locking assembly is typically employed to lock the relative rotation of the stator and rotor.

As shown in fig. 1a and 1b, in a camshaft phaser of the prior art, the rotor 20 is formed with a mounting hole 20h extending in the axial direction a, and the end cover 30 is formed with a lock hole 30h extending in the axial direction a, the lock hole 30h being opposite to the mounting hole 20h in the axial direction a. The support 101, the coil spring 102 and the locking pin 103 of the locking assembly 10 are installed in the installation hole 20h of the rotor 20, and the locking sleeve 104 of the locking assembly 10 is installed in the locking hole 30h of the end cover 30. More specifically, the support 101 is entirely located in the mounting hole 20h of the rotor 20, the coil spring 102 is fitted around the radially outer side of the guide post of the support 101 and one end (right-hand end in the drawing) of the coil spring 102 abuts against the lock pin 103 and the other end abuts against the base of the support 101, and the lock pin 103 is fitted around the coil spring 102. When the lock assembly 10 is in the locked state, one end (right-hand end in the drawing) of the lock pin 103 protrudes in the axial direction a into the lock sleeve 104 in the lock hole 30h of the end cover 30, so that the rotor 20 cannot rotate relative to the end cover 30, that is, the rotor 20 cannot rotate relative to the stator 40.

As shown in fig. 2a and 2b, in another camshaft phaser of the prior art, the stator 40 is formed with a mounting hole 40h extending in the radial direction R, the rotor 20 is formed with a lock hole 20h1 extending in the radial direction R, and the lock hole 20h1 is opposite to the mounting hole 40h in the radial direction R. Similar to the structure of the camshaft phaser of fig. 1a and 1b, the support 101, the coil spring 102, and the lock pin 103 of the lock assembly 10 are mounted within the mounting bore 40h of the stator 40. When the lock assembly 10 is in the locked state, one end (radially inner end) of the lock pin 103 protrudes in the radial direction R into the lock hole 20h1 of the rotor 20, so that the rotor 20 cannot rotate relative to the stator 40.

The inventors of the present invention have found that the following drawbacks exist in the above-described prior art camshaft phaser:

on the one hand, in the camshaft phaser of the prior art shown in fig. 1a and 1b, the structure of the end cover 30 is complicated, the locking hole 30h needs to be formed and the locking sleeve 104 needs to be installed, resulting in high cost of the end cover 30, and the assembly process is complicated as the locking gap between the locking pin 103 and the locking sleeve 104 needs to be adjusted by assembly; and

on the other hand, in the camshaft phaser of the prior art shown in fig. 2a and 2b, the rotor 20 and the stator 40 need to be machined to form the lock hole 20h1 and the mounting hole 40h, respectively, and the design of the lock hole 20h1 and the mounting hole 40h for the portions corresponding to the respective components of the lock assembly 10 can greatly increase the difficulty and cost of machining the rotor 20 and the stator 40. Further, when the lock assembly 10 is unlocked from the locked state, it is necessary to introduce hydraulic oil to the radially inner side of the radially inner end of the lock pin 103, and for this purpose, as shown in fig. 2a, a dedicated oil passage 20h2 for inputting this hydraulic oil is formed in the rotor 20. The oil passage 20h2 is excessively complicated in structure due to the inclusion of the radial portion extending in the radial direction R and the axial portion extending in the axial direction a, which are connected to each other.

Disclosure of Invention

The present invention has been made in view of the above-mentioned drawbacks of the prior art. It is an object of the present invention to provide a camshaft phaser that is simple in construction in relation to the lock assembly and does not require assembly adjustment of the lock clearance of the lock assembly.

Therefore, the invention adopts the following technical scheme.

The present invention provides a camshaft phaser comprising a rotor, a stator, and a lock assembly, the rotor being rotatable relative to the stator, the lock assembly being mounted to the rotor so as to be able to lock relative rotation between the rotor and the stator, the lock assembly comprising: an elastic member mounted in the mounting hole of the rotor, a central axis of the elastic member extending substantially in a radial direction of the rotor such that the elastic member can be compressed and extended in the radial direction of the rotor, and a radially inner end of the elastic member being pressed against the rotor; and the locking pin is arranged in the mounting hole of the rotor, and the radial outer side end of the elastic piece is pressed against the locking pin, so that the locking pin can move towards the radial outer side under the action of the elastic force of the elastic piece to be connected with the stator in a clamping manner to lock.

Preferably, the mounting hole is a blind hole, and at least one through hole is formed at the bottom of the mounting hole, and the at least one through hole enables the mounting hole to communicate with the outside of the rotor.

More preferably, the at least one through hole extends in an axial direction of the rotor.

Preferably, the rotor includes a cylindrical rotor main body and a plurality of rotor blades projecting from the rotor main body toward a radially outer side, the mounting hole is formed in one of the plurality of rotor blades, the mounting hole extends in a radial direction of the rotor, and the mounting hole opens at a radially outer side face of the one rotor blade.

More preferably, a wall surface of the one rotor blade, which is used to form the mounting hole, is formed with a stepped portion that protrudes toward a radially inner side of the mounting hole itself, a radially inner end of the elastic member is pressed against the stepped portion, and a part of the lock pin is inserted into the elastic member so that the elastic member is located between the lock pin and the wall surface.

More preferably, the locking assembly further includes a supporting member, the supporting member is mounted to the mounting hole, the supporting member includes a base and a guide post protruding from the base, a radially inner end of the elastic member is pressed against a connecting portion of the base, the connecting portion being connected to the guide post, and the elastic member is sleeved on a radially outer side of the guide post itself, and the locking pin is sleeved on a radially outer side of the elastic member itself in a manner of at least partially surrounding the elastic member and the guide post, so that the elastic member is located between the guide post and the locking pin.

More preferably, the stator includes a stator main body and a plurality of stator vanes extending from the stator main body toward a radially inner side, a locking portion recessed toward a radially outer side is formed at a portion of the stator main body facing the mounting hole in the locked state of the locking assembly, and the locking pin extends into the locking portion by an elastic force of the elastic member when the locking assembly is in the locked state.

More preferably, a portion of a radially outer bottom of the locking portion is formed with an oil guide groove depressed toward a radially outer side such that the locking pin and the oil guide groove face each other when the locking assembly is in the locked state.

More preferably, the oil-guiding groove extends in the axial direction over the entire axial dimension of the stator.

Preferably, the stator and/or the rotor are formed by powder metallurgy forming.

By adopting the technical scheme, the invention provides the novel camshaft phaser, the locking assembly of the camshaft phaser is radially arranged on the rotor and can be directly clamped with the stator to realize locking, so that the structure of the camshaft phaser relative to the locking assembly is simple, and the locking gap of the locking assembly does not need to be assembled and adjusted.

Drawings

FIG. 1a is an axial cross-sectional schematic view of a camshaft phaser of the prior art; fig. 1b is a schematic diagram of the structure of the camshaft phaser of fig. 1a as viewed from the axial side.

FIG. 2a is an axial cross-sectional schematic view of another camshaft phaser of the prior art; fig. 2b is a schematic radial cross-sectional view of the camshaft phaser of fig. 2a showing the internal structure of the camshaft phaser of fig. 2 a.

Fig. 3a is an axial cross-sectional schematic view of a camshaft phaser according to a first embodiment of the present invention; FIG. 3b is a schematic radial cross-sectional view of the camshaft phaser of FIG. 3a showing an internal structure of the camshaft phaser of FIG. 3 a; FIG. 3c is a perspective view of a partial structure of a stator of the camshaft phaser of FIG. 3 a; fig. 3d is a schematic view of the rotor of the camshaft phaser of fig. 3a with the lock assembly in a rotor mounted state.

Fig. 4a is an axial cross-sectional schematic view of a camshaft phaser according to a second embodiment of the present invention; fig. 4b is a schematic radial cross-sectional view of the camshaft phaser of fig. 4a showing the internal structure of the camshaft phaser of fig. 4 a.

Description of the reference numerals

10 Lock Assembly 101 support 102 coil spring 103 Lock Pin 104 Lock Sleeve 20 rotor 20h mounting hole 20h1 Lock hole 20h2 oil passage 30 end cap 30h Lock hole 40 stator 40h mounting hole

1 Lock Assembly 11 support 111 base 112 guide post 12 coil spring 13 Lock Pin step 132 radial inside part 133 recess 13h Lock gap 2 rotor 21 rotor body 22 rotor body 21h1 mounting hole 21h2 through hole 21s step 3 stator 31 stator blade 32 stator body 321 Lock part 322 oil guide groove

Axial direction of A, R, radial direction of C, circumferential direction of C

Detailed Description

The technical scheme of the invention is explained in the following with the accompanying drawings of the specification. The camshaft phaser according to the present invention has a generally cylindrical shape as a whole, and the axial, radial and circumferential directions of the present invention refer to the axial, radial and circumferential directions of the camshaft phaser (stator and rotor), respectively, unless otherwise specified.

(first embodiment)

As shown in fig. 3a to 3b, the camshaft phaser according to the first embodiment of the present invention is generally cylindrical in shape. The camshaft phaser includes a lock assembly 1, a rotor 2, and a stator 3.

The rotor 2 is disposed radially inside the stator 3 and is rotatable relative to the stator 3. The stator 3 includes a cylindrical stator main body 32 and a plurality of stator blades 31 projecting radially inward from the stator main body 32. The rotor 2 includes a cylindrical rotor body 22 and a plurality of rotor blades 21 projecting radially outward from the rotor body 22. The plurality of stator blades 31 and the plurality of rotor blades 21 are alternately arranged in the circumferential direction C such that each rotor blade 21 is located between two adjacent stator blades 31. Thus, the space between two adjacent stator vanes 31 is partitioned into two oil chambers independent of each other by the rotor blade 21 located between the two stator vanes 31. Four sets of oil chambers distributed along the circumferential direction C are formed in the camshaft phaser shown in fig. 3a and 3b, each set of oil chambers including two oil chambers, which are respectively communicated with the oil supply device through independent oil passages formed in the rotor main body 22.

In the present embodiment, as shown in fig. 3b and 3d, one rotor blade 21 of the four rotor blades 21 is formed with a mounting hole 21h1 for mounting the locking assembly 1, and the mounting hole 21h1 is open to the radially outer side of the one rotor blade 21. Preferably, the mounting hole 21h1 is a blind hole, and the bottom of the mounting hole 21h1 is formed with two through holes 21h2 extending in the axial direction a, the two through holes 21h2 communicating the mounting hole 21h1 with the outside of the rotor 2, so that air and hydraulic oil remaining in the mounting hole 21h1 can be discharged through the two through holes 21h 2.

In the present embodiment, the lock assembly 1 is mounted in the mounting hole 21h1 of the above-described one rotor blade 21 so as to be able to lock the relative rotation between the rotor 2 and the stator 3. The locking assembly 1 comprises a coil spring 12 and a locking pin 13.

Specifically, the coil spring 12 as the elastic member is preferably a cylindrical coil spring 12. The coil spring 12 is mounted in the mounting hole 21h1 of the above-indicated one rotor blade 21 such that the center axis of the coil spring 12 extends substantially in the radial direction R, thereby enabling the coil spring 12 to be compressed and extended in the radial direction R.

Further, the wall surface of the rotor blade 21 for forming the mounting hole 21h1 is formed with a stepped portion 21s that protrudes toward the radially inner side of the mounting hole 21h1 itself over the entire circumference along the circumferential direction of the mounting hole 21h1, and the radially inner end of the coil spring 12 is pressed against the stepped portion 21 s.

The lock pin 13 is also attached to the attachment hole 21h1 of the above-indicated one rotor blade 21, and the radially outer end of the coil spring 12 is pressed against the lock pin stepped portion 131 of the lock pin 13, so that the lock pin 13 can move in the radial direction R by the spring force of the coil spring 12. More specifically, the coil spring 12 is fitted to the radially inner portion 132 of the lock pin 13 such that the coil spring 12 is located between the radially inner portion 132 of the lock pin 13 and the wall surface of the rotor blade 2 for forming the mounting hole 21h 1.

In the present embodiment, as shown in fig. 3b and 3c, a locking portion 321 that is recessed radially outward is formed at a portion of the stator main body 32 that faces the attachment hole 21h1 when the lock assembly 1 is in the locked state. When the locking unit 1 is in the locked state, the locking pin 13 is inserted into the locking portion 321 by the spring force of the coil spring 12 to engage with the stator 3, thereby achieving locking. Thus, the lock clearance 13h between the lock pin 13 and the wall surface of the stator main body 32 for forming the lock portion 321 can be secured only by the dimensional tolerances of the rotor 2 and the stator 3 without performing assembly adjustment.

Further, as shown in fig. 3b and 3c, a part of the bottom of the radially outer side of the locking portion 321 is formed with an oil guide groove 322 recessed toward the radially outer side, so that the locking pin 13 is opposed to the oil guide groove 322 when the locking assembly 1 is in the locked state. Thus, hydraulic oil can flow between the stator main body 32 and the lock pin 13 through the oil guide groove 322, so that the lock pin 13 can move toward the radially inner side against the spring force of the coil spring 12 to complete unlocking. In the present embodiment, the oil guide groove 322 extends along the axial direction a over the entire axial dimension of the stator 3.

(second embodiment)

As shown in fig. 4a to 4b, the basic structure of the camshaft phaser according to the second embodiment of the present invention is substantially the same as that of the camshaft phaser according to the first embodiment of the present invention, with the difference therebetween being: in this embodiment, the locking assembly 1 further includes a support 11, and the coil spring 12 and the locking pin 13 are mounted to the support 11.

Specifically, the support 11 includes a base 111 that matches the bottom shape of the mounting hole 21h1 of the rotor 2 and a guide post 112 that projects toward the radial outside from the base 111. The support 11 is fitted into the fitting hole 21h1 of the rotor 2 and the coil spring 12 is fitted around the radially outer side of the guide post 112 itself, and the radially inner end of the coil spring 12 abuts on the connecting portion of the base 111 with the guide post 112. The locking pin 13 is fitted radially outside the coil spring 12 itself and partially surrounds the coil spring 12 and the guide post 112 such that the coil spring 12 is located between the guide post 112 and the locking pin 13. In this embodiment, the operating principle of the lock assembly 1 is the same as that of the lock assembly of the camshaft phaser according to the first embodiment of the present invention, and will not be described herein again. The present embodiment can achieve the same effect as the first embodiment, and in addition, since the locking assembly 1 further includes the support member 11 in the present embodiment, the operation of the locking assembly is more stable.

Although the above embodiments have explained the technical solutions of the present invention in detail, it should be noted that:

1. as shown in fig. 3a and 3b, the radially outer side surface of the locking pin 13 may be formed with a recess 133 recessed toward the radially inner side, the recess 133 being adapted to face the oil guide groove 322 when the locking assembly 1 is in the locked state. In this way, sufficient space is formed between the recess 133 and the oil guide groove 322 for the inflow of hydraulic oil, so that it is further ensured that the locking pin 13 is moved radially inward under the pressure of the hydraulic oil to unlock the locking assembly 1.

2. The number of the through holes 21h2 formed at the bottom of the mounting hole 21h1 of the rotor 2 is not limited to the number described in the above embodiment, and only one through hole 21h2 may be formed, for example.

3. Preferably, an annular groove is formed at a portion where the base 111 of the support 11 is connected to the guide post 112 such that a radially inner end of the coil spring 12 abuts therein.

4. Preferably, both the stator 3 and the rotor 2 are formed by powder metallurgy forming.

5. Although it is described in the above embodiment that the oil guide groove 322 extends over the entire axial dimension of the stator 3 along the axial direction a, the present invention is not limited thereto. The oil-guiding groove 322 may also extend over a part of the axial dimension of the stator 3.

Claims

A camshaft phaser comprising a rotor, a stator, and a lock assembly, the rotor being rotatable relative to the stator, the lock assembly being mounted to the rotor to enable locking of relative rotation between the rotor and the stator, the lock assembly comprising:

an elastic member mounted in the mounting hole of the rotor, a central axis of the elastic member extending substantially in a radial direction of the rotor such that the elastic member can be compressed and extended in the radial direction of the rotor, and a radially inner end of the elastic member being pressed against the rotor; and

the locking round pin, the locking round pin install in the mounting hole of rotor, the radial outside end of elastic component press support in the locking round pin makes the locking round pin is in under the effect of the elastic force of elastic component can move in order with the stator joint carries out the locking.
A camshaft phaser as in claim 1 wherein said mounting bore is a blind bore, the bottom of said mounting bore being formed with at least one through bore communicating the mounting bore with the exterior of the rotor.
The camshaft phaser of claim 2, wherein the at least one through bore extends in an axial direction of the rotor.
A camshaft phaser as claimed in any one of claims 1 to 3, wherein said rotor includes a cylindrical rotor main body and a plurality of rotor vanes projecting radially outward from the rotor main body, said mounting hole is formed in one of said plurality of rotor vanes, said mounting hole extends in a radial direction of said rotor, and said mounting hole opens at a radially outer side face of the one rotor vane.
The camshaft phaser of claim 4, wherein the wall surface of said one rotor blade forming said mounting hole is formed with a step portion projecting toward the radially inner side of said mounting hole itself, the radially inner end of said elastic member is pressed against said step portion, and a part of said lock pin is inserted into said elastic member so that said elastic member is located between said lock pin and said wall surface.
A camshaft phaser as in claim 4 wherein said lock assembly further comprises a support member mounted to said mounting bore,

the support piece comprises a base and a guide column protruding from the base, the radial inner end of the elastic piece is pressed against the connecting part of the base, which is connected with the guide column, the elastic piece is sleeved on the radial outer side of the guide column, and the locking pin is sleeved on the radial outer side of the elastic piece in a mode of at least partially surrounding the elastic piece and the guide column, so that the elastic piece is located between the guide column and the locking pin.
A camshaft phaser as in any of claims 4-6 wherein the stator comprises a stator body and a plurality of stator vanes projecting radially inward from the stator body, a region of the stator body opposite the mounting hole in the locked state of the lock assembly is formed with a locking portion recessed radially outward,

when the locking assembly is in a locking state, the locking pin extends into the locking part under the action of the elastic force of the elastic piece.
A camshaft phaser as in claim 7 wherein a portion of a radially outer bottom of the lock portion is formed with an oil guide groove recessed toward the radially outer side such that the lock pin and the oil guide groove face each other when the lock assembly is in the locked state.
A camshaft phaser as in claim 8 wherein said oil guide groove extends axially over the entire axial dimension of said stator.
A camshaft phaser as in any of claims 1-9 wherein the stator and/or the rotor are formed by powder metallurgy forming.