WO2022141637A1

WO2022141637A1 - Cam phase adjuster

Info

Publication number: WO2022141637A1
Application number: PCT/CN2021/070164
Authority: WO
Inventors: 盛慧芳; 李欣
Original assignee: 舍弗勒技术股份两合公司
Priority date: 2021-01-04
Filing date: 2021-01-04
Publication date: 2022-07-07

Abstract

A cam phase adjuster, comprising a stator (10) and a rotor (20); the stator (10) surrounds the radial outer side of the rotor (20), the stator (10) is provided with stator blades (12) extending radially inwards, the rotor (20) is provided with rotor blades (22) extending radially outwards, and the stator blades (12) and the rotor blades (22) are opposite each other in a circumferential direction so as to form hydraulic cavities therebetween; and the rotor (20) can rotate relative to the stator (10) to a limit position where the rotor blades (22) are closest to the stator blades (12) in the circumferential direction and can be locked at the limit position. The cam phase adjuster further comprises elastic buffering members (30), and when the rotor (20) is located at the limit position, the elastic buffering members (30) can elastically abut between the stator blades (12) and the rotor blades (22) in a rotation direction. The cam phase adjuster can reduce vibration noise.

Description

Cam Phaser

technical field

The present invention relates to the technical field of vehicles. In particular, the present invention relates to a cam phaser for an engine timing system.

Background technique

In the internal combustion engine of modern vehicles, the variable valve timing (VVT) system is usually used to change the phase relationship between the crankshaft and the camshaft between an advanced position and a retarded position in order to adjust the valve opening of the internal combustion engine. Combination time and intake and exhaust volume, so as to obtain the best combustion efficiency. The main component of the VVT system is the cam phaser. The cam phase adjuster includes a relatively rotatable stator and a rotor, wherein the rotor is coaxially mounted on the radial inner side of the stator, and a plurality of hydraulic chambers are formed between the rotor and the stator. The flow of hydraulic fluid into and out of these hydraulic chambers can be controlled by oil control valves installed in the rotors, which in turn can change the phase relationship between the crankshaft and the camshaft in a targeted manner. When the oil control valve can supply hydraulic fluid to the hydraulic chamber, the phase of the rotor relative to the stator can be controlled by the supply amount of the hydraulic fluid. However, in some cases, such as when the engine is started, the hydraulic fluid supply is insufficient and a locking mechanism may be required to lock the rotor in a certain rotational position.

For example, CN 102840003 A discloses a typical design of a cam phase adjuster. The stator and the rotor respectively have a plurality of blades corresponding to each other, and each rotor blade extends between two adjacent stator blades in the circumferential direction, thereby forming a hydraulic chamber for storing hydraulic fluid. A locking pin that can move axially is installed in the rotor blade. When the rotor rotates to a certain position relative to the stator, the locking pin can be inserted into the locking hole on the end cover of the stator, thereby locking the rotational position of the rotor. When this locked position is the limit position where the rotor blades can contact the stator blades, due to the clearance fit between the locking holes and the locking pins, the rotor may vibrate under the action of dynamic torque from the camshaft, causing the rotor blades and the stator to vibrate. The blades collide, causing noise.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is to provide a cam phase adjuster capable of reducing vibration noise.

The above technical problems are solved by a cam phase adjuster according to the present invention. The cam phase adjuster includes a stator and a rotor, the stator surrounds the radial outer side of the rotor, the stator has stator blades extending radially inward, the rotor has rotor blades extending radially outward, and the stator blades are circumferentially opposite to the rotor blades Thus, a hydraulic chamber is formed between the two. The rotor is rotatable relative to the stator to a limit position where the rotor blades are circumferentially closest to the stator blades and can be locked in the limit position. Wherein, the cam phase adjuster further includes an elastic buffer member, and when the rotor is at the limit position, the elastic buffer member can elastically abut between the stator blade and the rotor blade along the rotation direction. The stator and the rotor may respectively have a plurality of sets of blades corresponding to each other, and when the rotor is locked in the limit position, at least one rotor blade may abut on the adjacent stator blade in the rotational direction, so that it may be affected by the torque vibration from the camshaft. Vibration occurs down and hits the stator blades. An elastic buffer member is arranged between at least one stator blade and the corresponding rotor blade, so that when such vibration occurs, the rotor blade will first contact the elastic buffer member in the rotation direction, so that the vibration generation can be absorbed by the elastic deformation of the elastic buffer member impact force to reduce vibration and noise.

According to a preferred embodiment of the present invention, when the rotor is locked at the limit position, the elastic buffer member can always elastically abut between the stator blade and the rotor blade in a compressed state. Since the locking pin for locking the rotor in the limit position with respect to the stator is generally engaged with the locking hole in a clearance fit manner, the rotor can still rotate (vibrate) with a small amplitude relative to the stator when the rotor is locked in the limit position. In this case, "the elastic buffer member is always in a compressed state elastically abuts between the stator blade and the rotor blade" means that the rotor is always subjected to the elastic force of the elastic buffer member in the entire vibration range of the rotor in the locked state effect. Therefore, the elastic buffer can better reduce the tendency of the rotor to vibrate and absorb the energy generated by the vibration.

According to another preferred embodiment of the present invention, the elastic buffer may be mounted on one of the stator blade and the rotor blade. Thus, the resilient bumper can be positioned relative to one of the stator or the rotor without moving freely between the rotor blades and the stator blades during rotation of the rotor relative to the stator (unlocked state). Preferably, the elastic buffer member can be installed on the stator blade, because the stator blade usually has a large volume, which is convenient to provide sufficient installation space for the elastic buffer member, and the stator blade is a static part, which can better ensure the elastic buffer member. The installation status is stable.

According to another preferred embodiment of the present invention, the elastic buffer member may be positioned at least in the circumferential and radial directions relative to one of the stator blade and the rotor blade on which the elastic buffer member is installed. In other words, the elastic buffer is constrained by the mounting member at least in the circumferential and radial directions, so that it can stably abut between the rotor blade and the stator blade in the rotational plane.

According to another preferred embodiment of the present invention, one of the stator blade and the rotor blade in which the elastic buffer member is installed may have a mounting groove on a side facing the other in the rotation direction, and the elastic buffer member may be installed in the installation groove, A part of the elastic buffer member may protrude out of the installation groove in the rotation direction. For example, the mounting groove can realize the positioning of the elastic buffer member in a form-fitting manner. The portion of the elastic buffer that protrudes out of the mounting slot may be used to abut the other of the stator blade and the rotor blade where the elastic buffer is not installed.

According to another preferred embodiment of the present invention, the elastic buffer member may be an arcuate reed, which has an arcuate shape when viewed in a plane perpendicular to the rotational axis of the rotor, and the middle portion of the arcuate reed protrudes into the installation groove In addition, both ends of the bow spring are installed inside the installation groove. Both ends of the bow-shaped spring can be used to cooperate with the installation groove to achieve positioning, and the arched part in the middle has high elasticity and can be used to abut the stator blade and the rotor blade without the elastic buffer.

According to another preferred embodiment of the present invention, the mounting groove can constrain both ends of the bow spring at least in the circumferential and radial directions in a form-fitting manner. For example, recesses for accommodating the ends of the bow springs may be formed in the mounting grooves, and both ends of the bowed springs may be respectively inserted into the corresponding recesses, so as to not be easily disengaged from the mounting grooves.

According to another preferred embodiment of the present invention, when the bow-shaped spring does not abut the other one of the stator blade and the rotor blade without the elastic buffer member installed, at least one end of the bow-shaped spring and the installation groove may exist in the radial direction gap. According to the deformation mode of the bow-shaped spring, when the middle portion of the bow-shaped spring is elastically deformed by being squeezed, the distance between the two ends tends to become larger. Therefore, such a gap reserves a space for the elastic deformation of the bow-shaped spring, thereby helping to ensure that the bow-shaped spring can provide sufficient elastic force.

According to another preferred embodiment of the present invention, one end of the installation slot in the axial direction may be closed by one of the stator blade and the rotor blade in which the elastic buffer is installed, and the other end in the axial direction may penetrate through the stator blade and the rotor blade and install the elastic buffer member. An end face of one of the elastic buffers. This mounting groove is similar to a blind hole in the axial direction, and its open end in the axial direction is convenient for installing the elastic buffer into the mounting groove.

According to another preferred embodiment of the present invention, when the elastic buffer member is installed in the installation groove, there may be an axial interval between the elastic buffer member and the end face penetrated by the installation groove. Therefore, the elastic buffer is less likely to interfere with the end cover of the stator.

Description of drawings

The present invention is further described below with reference to the accompanying drawings. Functionally identical elements are represented in the figures by the same reference numerals. in:

FIG. 1 shows a schematic diagram of a cam phase adjuster according to an embodiment of the present invention;

FIG. 2 shows a partial enlarged view of a cam phase adjuster according to an embodiment of the present invention;

FIG. 3 shows a schematic diagram of a stator of a cam phase adjuster according to an embodiment of the present invention; and

FIG. 4 shows a schematic diagram of an elastic buffer of a cam phase adjuster according to an embodiment of the present invention.

Detailed ways

Specific embodiments of the cam phase adjuster according to the present invention will be described below with reference to the accompanying drawings. The following detailed description and accompanying drawings are used to illustrate the principles of the present invention by way of example, the present invention is not limited to the described preferred embodiments, and the protection scope of the present invention is defined by the claims.

According to an embodiment of the present invention, a cam phaser for an engine timing system of a motor vehicle is provided. 1 to 4 illustrate an exemplary embodiment of a cam phase adjuster according to the present invention.

FIG. 1 shows a schematic view of the cam phase adjuster according to the present embodiment viewed in the axial direction. As shown in FIG. 1 , the cam phase adjuster includes a stator 10 , a rotor 20 and a lock pin 40 . The stator 10 surrounds the radially outer side of the rotor 20 and has a substantially annular stator body 11 and a plurality of stator blades 12 extending radially inward from the stator body 11 . The rotor 20 is coaxially mounted on the radially inner side of the stator 10 and is rotatable relative to the stator 10 about a central axis parallel to the axial direction. The rotor 20 has a substantially disk-shaped rotor body 21 and a plurality of rotor blades 22 extending radially outward from the rotor body 21 . The number of stator blades 12 and rotor blades 22 is the same, and can preferably be arranged uniformly in the circumferential direction, respectively. Each rotor blade 22 extends radially between two circumferentially adjacent stator blades 12 and abuts the stator body 11 ; each stator blade 12 extends radially between two circumferentially adjacent rotor blades 22 , and abuts the rotor body 21 . Thus, a hydraulic chamber in which hydraulic fluid can be stored is formed between each pair of circumferentially opposed stator blades 12 and rotor blades 22 .

The rotor 20 can rotate relative to the stator 10 under the action of hydraulic fluid in the hydraulic chamber. The circumferential positional relationship of the stator blades 12 to the rotor blades 22 defines the range of rotation of the rotor 20 relative to the stator 10 . When any one of the plurality of rotor blades 22 abuts against the corresponding stator blade 12 in the rotational direction, the rotor 20 reaches its rotational limit position. In the extreme position, each rotor blade 22 is at the position closest to the corresponding stator blade 12 in the circumferential direction, but not each rotor blade 22 can abut the corresponding stator blade 12 together. There may be situations where one or more pairs of vanes cannot abut together in extreme positions. Generally speaking, it is enough to satisfy the positioning requirement that only a pair of blades can abut each other in the circumferential direction at the extreme position. In FIG. 1 , when the rotor 20 is rotated to the limit position, only the pair of blades in the lower left corner of the figure can abut each other, and there are circumferential gaps between other rotor blades 22 and the corresponding stator blades 12 . A pair of vanes that can abut each other may be referred to as positioning vanes, and a pair or pairs of vanes that cannot abut each other may be referred to as non-locating vanes.

The locking pin 40 is mounted in the rotor 20 , in particular in one of the rotor blades 22 , and can slide axially relative to the rotor 20 . A locking hole (not shown) is formed in the stator end cover of the cam phase adjuster. The stator end cover is relatively fixed to the stator 10 . When the rotor 20 is rotated relative to the stator 10 to the limit position shown in FIG. 1 , the locking pin 40 is aligned with the locking hole so as to be insertable into the locking hole to lock the rotor 20 relative to the stator 10 in the limit position. In order to facilitate the engagement and disengagement of the locking pin 40 and the locking hole, the locking pin 40 and the locking hole are usually a clearance fit, so the rotor 20 locked in the limit position may vibrate relative to the stator 10, causing the rotor blades 22 to strike the stator blades 12 (especially is the positioning blade).

In order to buffer the vibration, the cam phase adjuster further includes an elastic buffer member 30 . FIG. 2 shows a partial enlarged view of the cam phase adjuster of FIG. 1 at the elastic buffer member 30 . As shown in FIG. 2 , an elastic buffer 30 is provided between one stator blade 12 and the corresponding rotor blade 22 . When the rotor 20 rotates to the limit position, the elastic buffer member 30 can elastically abut between the stator blade 12 and the corresponding rotor blade 22 along the rotation direction. When the rotor 20 locked in the limit position vibrates, the rotor 20 reciprocates with respect to the stator 10 in a small amplitude, so the rotor blades 22 are also at a position closest to the corresponding stator blade 12 and a position farthest from the corresponding stator blade 12 vibration between positions. During this vibration process, at least at the position where the rotor blade 22 is closest to the corresponding stator blade 12 , the elastic buffer 30 elastically abuts between the rotor blade 22 and the stator blade 12 in an elastically compressed state. Preferably, in the entire vibration range, the elastic buffer member 30 between the rotor blade 22 and the stator blade 12 is always in a state of elastic compression. That is to say, as long as the rotor 20 is in or locked at the limit position, no matter whether the rotor 20 vibrates and to which transient position the vibration occurs, the elastic buffer member 30 always elastically abuts between the rotor blade 22 and the stator blade 12 in an elastically compressed state. between. Therefore, the rotor blade 22 vibrating at the extreme position will be damped and buffered by the elastic buffer member 30, so that the rotor blade 22 can be prevented from directly hitting the stator blade 12, or the impact force of the rotor blade 22 on the stator blade 12 can be at least reduced, thereby reducing the impact of the rotor blade 22 on the stator blade 12. vibration noise.

Since the rotations of the plurality of blades of the rotor 20 are synchronized, the elastic buffer member 30 only needs to be arranged between a pair of rotor blades 22 and the stator blades 12 to suppress the vibration and noise between all blades. Of course, elastic buffer members 30 may also be respectively provided between multiple pairs of blades as required, that is, the cam phase adjuster may have a plurality of such elastic buffer members 30 to improve the buffer effect. However, in order to avoid the influence on the positioning accuracy of the rotor 20, it is preferable not to dispose the elastic buffer member 30 between the above-mentioned positioning blades that can be directly contacted. In addition, since the rotor 20 can rotate both clockwise and counterclockwise, there are generally two extreme positions corresponding to the two rotating directions respectively. In this case, preferably one or a group of elastic buffer members 30 can be respectively provided for the extreme positions of the two rotation directions, wherein the elastic buffer members 30 for different rotation directions are arranged on two opposite sides of the stator blade 12 in the circumferential direction. side.

To position the resilient bumper 30 , the resilient bumper 30 may be mounted on one of the stator blade 12 and the rotor blade 22 . The resilient bumper 30 is preferably positioned relative to the blade at least circumferentially and radially, ie bounded by the blade at least circumferentially and radially. This means that the elastic buffer 30 cannot move freely relative to the blade in a plane perpendicular to the axis of rotation of the rotor 20 . This does not mean, however, that the two have to be completely fixed together, so they can be mounted together, for example, by means of a clearance fit. As shown in FIG. 2 , in this embodiment, the elastic buffer member 30 is installed on the stator blade 12 . This is because the volume of the stator blades 12 is generally large and is generally in a stationary state, thus facilitating easy and stable installation of the elastic buffers 30. However, the elastic buffer member 30 can also be installed on the rotor blade 22 instead according to actual needs.

FIG. 3 shows a perspective view of the stator 10 of the cam phase adjuster according to an embodiment of the present invention. As shown in FIG. 3 , preferably, a mounting groove 13 for accommodating the elastic buffer member 30 may be formed on the stator blade 12 . The mounting grooves 13 are formed on the side surfaces of the stator blades 12 facing the respective rotor blades 22 in the rotational direction, and are recessed substantially in the circumferential direction from the side surfaces. As shown in FIG. 2 , when the elastic buffer member 30 is installed in the installation groove 13 , a part of the elastic buffer member 30 protrudes out of the installation groove 13 substantially in the rotational direction so as to abut the rotor blade 22 .

In the present embodiment, the elastic buffer member 30 is schematically shown as a bow-shaped spring. As shown in FIG. 2 , the arcuate reed has a generally arcuate (or arcuate) shape when viewed in a plane perpendicular to the rotational axis of the rotor 20 . The arched middle portion of the bow-shaped leaf spring protrudes out of the mounting groove 13 , and its opposite ends substantially in the radial direction abut inside the mounting groove 13 . Preferably, as shown in FIG. 4 , both ends of the bow spring can be bent into a hook shape. As shown in FIG. 2 , two radially opposite ends of the mounting groove 13 may be formed with recesses which are further recessed substantially in the radial direction, and the hook-shaped ends of the bow-shaped springs are inserted into the recesses at both ends of the mounting groove 13, so that the The form-fitting manner constrains the bow-shaped spring in the circumferential and radial directions, preventing the bow-shaped spring from falling off from the mounting groove 13 . In addition, preferably, when the arcuate reed mounted on the stator blade 12 is not in contact with the rotor blade 22, the arcuate reed has not been elastically deformed due to the relative extrusion of the two blades, and at least one end of the arcuate reed is in contact with the installation groove. There may be gaps between 13 in the radial direction. Based on the deformation mode of the bow-shaped reed, when the bow-shaped reed is elastically deformed by being squeezed by two blades on both sides of the circumferential direction at the same time, the lengths of the two ends in the radial direction must become larger. Therefore, this clearance leaves room for the elastic deformation of the bow spring in the compressed state.

As shown in FIG. 3 , preferably, the installation slot 13 may be closed by the stator blade 12 at one end in the axial direction, and penetrate through the end face of the stator blade 12 at the other end in the axial direction. Therefore, the mounting groove 13 is similar to a blind hole in the axial direction. The elastic buffer 30 can be placed into the mounting groove 13 from the open axial end of the mounting groove 13 . The axial length of the elastic buffer member 30 is preferably smaller than the axial length of the installation groove 13 , so that when the elastic buffer member 30 is installed in the installation groove 13 , at the end face of the elastic buffer member 30 passing through the installation groove 13 of the stator blade 12 There is an axial space between them. Therefore, the elastic buffer member 30 will not protrude out of the installation groove 13 in the axial direction, and when the stator end cover (not shown) is installed on the end of the stator 10, the elastic buffer member 30 will not be in contact with the stator end cover. interference occurs.

As previously mentioned, the elastic buffer member 30 may also be seated on the rotor blade 22, in which case the above descriptions of the corresponding features of the mounting groove 13 and the elastic buffer member 30 still apply. Meanwhile, although the elastic buffer member 30 is described by taking the bow-shaped spring as an example in the above embodiment, other forms of elastic buffer member, such as a coil spring or a leaf spring, can also be used according to specific needs.

Although possible embodiments have been exemplarily described in the above description, it should be understood that there are still numerous variations of embodiments through all known and further combinations of technical features and implementations that are readily apparent to those skilled in the art. Furthermore, it should be understood that the exemplary embodiment is merely an example, and such an embodiment in no way limits the scope, applicability, and configuration of the present invention. The foregoing description is more of a technical guide for the skilled person to transform at least one exemplary embodiment, wherein various changes may be made without departing from the scope of protection of the claims, especially with regard to the described Changes in the function and structure of components.

Reference number table

10 Stator

11 Stator body

12 stator vanes

13 Mounting slot

20 rotors

21 Rotor body

22 rotor blades

30 Elastic buffers

40 Locking pins

Claims

A cam phase adjuster, comprising a stator (10) and a rotor (20), the stator (10) surrounding the radially outer side of the rotor (20), the stator (10) having a radially inner extending Stator blades (12), the rotor (20) having rotor blades (22) extending radially outward, the stator blades (12) being circumferentially opposite to the rotor blades (22) so as to be therebetween A hydraulic chamber is formed, the rotor (20) can be rotated relative to the stator (10) to a limit position where the rotor blades (22) are circumferentially closest to the stator blades (12) and can be locked in the limit position,

It is characterized in that,

The cam phase adjuster further includes an elastic buffer member (30), and when the rotor (20) is located at the limit position, the elastic buffer member (30) can elastically abut against the stator blade along the rotation direction (12) and the rotor blades (22).
The cam phase adjuster according to claim 1, characterized in that, when the rotor (20) is locked at the limit position, the elastic buffer member (30) is always in a compressed state and elastically abuts against the between the stator blades (12) and the rotor blades (22).
The cam phase adjuster according to claim 1, wherein the elastic buffer (30) is mounted on one of the stator blade (12) and the rotor blade (22).
The cam phase adjuster according to claim 3, wherein the elastic buffer member (30) is at least circumferentially and radially relative to the stator blade (12) and the rotor blade (22) The one is positioned.
The cam phaser according to claim 4, wherein the one of the stator blade (12) and the rotor blade (22) has a mounting on the side facing the other in the direction of rotation A groove (13), the elastic buffer member (30) is installed in the installation groove (13), and a part of the elastic buffer member (30) protrudes out of the installation groove (13) along the rotation direction.
The cam phase adjuster according to claim 5, characterized in that, the elastic buffer (30) is a bow-shaped spring, and viewed in a plane perpendicular to the rotation axis of the rotor (20), the bow-shaped spring The sheet has an arcuate shape, the middle part of the arcuate spring piece protrudes out of the installation groove (13), and the two ends of the arcuate spring piece are installed inside the installation groove (13).
The cam phase adjuster according to claim 6, characterized in that, the mounting groove (13) constrains both ends of the bow-shaped spring at least in the circumferential direction and the radial direction by means of a form fit.
The cam phase adjuster of claim 7, wherein when the arcuate reed does not abut the other of the stator blade (12) and the rotor blade (22), the There is a gap in the radial direction between at least one end of the bow-shaped spring and the installation groove (13).
The cam phase adjuster according to any one of claims 5 to 8, characterized in that, the mounting groove (13) is enclosed by the stator blade (12) and the rotor blade (22) at one end in the axial direction. The one is closed, and the other end in the axial direction penetrates the end face of the one of the stator blade (12) and the rotor blade (22).
The cam phase adjuster according to claim 9, characterized in that, when the elastic buffer member (30) is installed in the installation groove (13), the elastic buffer member (30) and the installed There is an axial space between the end faces through which the grooves (13) pass.