WO2019204984A1

WO2019204984A1 - Camshaft phaser

Info

Publication number: WO2019204984A1
Application number: PCT/CN2018/084268
Authority: WO
Inventors: 郭文萍; 钱其伟
Original assignee: 舍弗勒技术股份两合公司
Priority date: 2018-04-24
Filing date: 2018-04-24
Publication date: 2019-10-31
Also published as: CN111655980B; CN111655980A

Abstract

A camshaft phaser, comprising a stator (1), a rotor (2) and a locking assembly (3), wherein the rotor (2) is disposed at a radial inner side of the stator (1) and is capable of rotating relative to the stator (1), and a plurality of sets of oil chambers that are distributed circumferentially are formed between the rotor (2) and the stator (1), each set of oil chambers comprising a first oil chamber (A) and a second oil chamber (B) that are separated by rotor blades (22) of the rotor (2). When the camshaft phaser is in a locked state in which the rotor (2) is locked by the locking assembly (3) so as be incapable of rotating relative to the stator (1), the first oil chamber (A) and second oil chamber (B) in at least one oil chamber among the plurality of sets of oil chambers communicate such that, in the locked state, oil of the first oil chamber (A) may flow into the second oil chamber (B) such that a predetermined amount of oil may be retained in the second oil chamber (B). The described camshaft phaser eliminates high-frequency noise.

Description

Camshaft phaser

Technical field

The invention relates to a camshaft phaser.

Background technique

In the prior art, the engine valve timing system is a system for controlling the valve opening and closing time of the engine of the automobile, and the engine valve timing system optimizes the performance of the engine by controlling the opening and closing time of the valve. The engine valve timing system includes a camshaft phaser that generally includes two end caps on either side of the axial direction and a stator, rotor, and lock assembly mounted between the two end caps. The rotor is located radially inward of the stator and the rotor is rotatable relative to the stator, and the plurality of sets of oil chambers are enclosed by the rotor, the stator and the end cap.

1 is a schematic cross-sectional view of a prior art camshaft phaser. As shown in Fig. 1, the stator 1 is fixed to an end cover (not shown) by four connecting members 5, which include a cylindrical stator body 11 and projecting radially inward from the stator body 11. The plurality of stator projections 12; the rotor 2 includes a cylindrical rotor main body 21 and a plurality of rotor blades 22 projecting radially outward from the rotor main body 21. Each rotor blade 22 is located between two adjacent stator projections 12 such that the space between adjacent two stator projections 12 is separated by rotor blades 22 located between the two stator projections 12. Into two separate oil chambers. Further, a seal assembly 4 abutting against the stator main body 11 is provided at the tip end of the rotor blade 22 for isolating the two oil chambers from each other. Thus, in the camshaft phaser shown in FIG. 1, four groups of oil chambers distributed along the circumferential direction C are formed, each group of oil chambers including a first oil chamber A and a second oil chamber B, the first oil The chamber A and the second oil chamber B are respectively communicated with the oil supply device through independent oil passages (only the second oil passage 23 communicating with the second oil chamber B is shown in the drawing).

When the camshaft phaser having the above structure is in the locked state shown in FIG. 1, the rotor 2 is locked by the lock assembly 3 so as not to be rotatable relative to the stator 1, and at this time, the first oil chamber A is in the state of maximum volume. And the second oil chamber B is in a state of minimum volume. At this time, the rotor blade 22 abuts against the circumferential side protrusion 121 formed toward the second oil chamber B formed on one circumferential side of the stator protrusion 12, so that the second oil chamber B can retain the predetermined minimum volume. . Further, on the other side in the circumferential direction of the stator protrusion 12, a circumferential other side protrusion 122 that protrudes toward the first oil chamber A is formed, and the other side protrusion 122 is used to make the first oil chamber A Ability to retain a predetermined minimum volume.

In this locked state, only the first oil chamber A has oil, and the second oil chamber B has no oil. However, since there is a lock gap between the lock pin of the lock assembly 3 and the corresponding pin hole, even in the locked state, the stator 1 and the rotor 2 still have a slight relative rotation due to the torque of the cam shaft, thereby Cause high frequency torsional vibration. In this case, since there is no oil in the second oil chamber B in each group of oil chambers of the camshaft phaser in the locked state, the rotor 2 is opposite to the stator 1 on the side facing the second oil chamber B. There is no buffering when rotating, and the rotor 2 collides with the stator 1 to generate noise. According to the research of the inventor of the present application, for the prior art camshaft phaser in FIG. 1, the torsional vibration frequency, the valve seating frequency and the main noise frequency complained by the user are both at 1000 Hz, for which the reason is reduced. This high frequency noise has become an urgent problem to be solved.

Summary of the invention

The present invention has been made based on the above-described drawbacks of the prior art. It is an object of the present invention to provide a camshaft phaser capable of eliminating high frequency noise caused by a locking gap of a camshaft phaser in a locked state.

In order to achieve the above object, the present invention adopts the following technical solutions.

The present invention provides a camshaft phaser including a stator, a rotor, and a lock assembly, the rotor being disposed radially inward of the stator and rotatable relative to the stator, Forming a plurality of sets of oil chambers distributed circumferentially between the rotor and the stator, each set of the oil chambers including a first oil chamber and a second oil chamber separated by rotor blades of the rotor, The camshaft phaser is in a locked state in which the rotor is locked by the locking assembly to be non-rotatable relative to the stator, the first of the at least one of the plurality of sets of oil chambers An oil chamber is electrically connected to the second oil chamber such that oil in the first oil chamber can flow into the second oil chamber in the locked state to retain a predetermined amount of the oil in the second oil chamber oil.

Preferably, the stator is formed with a communication passage in which the first oil chamber and the second oil chamber of the at least one oil chamber are unidirectionally communicated through the communication passage.

More preferably, a check valve is disposed in the communication passage to make the communication passage unidirectional.

Preferably, the first oil chamber is in communication with an oil supply device through a first oil passage formed in the rotor, and the second oil chamber is separated from the first oil passage by being formed in the rotor a second oil passage is in communication with the oil supply device, and in the locked state, the second oil passage corresponding to the second oil chamber in the at least one set of oil chambers is closed, such that The oil flowing into the second oil chamber of the first oil chamber cannot flow out through the second oil passage.

More preferably, in the locked state, a radially outer opening of the second oil passage corresponding to the second oil chamber of the at least one oil chamber is closed by the stator such that the The second oil passage is closed.

More preferably, in the locked state, the second oil passage corresponding to the second oil chamber in the other group of oil chambers other than the at least one oil chamber is turned on, such that The oil of the oil supply device can flow into the second oil chamber via the second oil passage.

Preferably, the locking assembly is disposed on the rotor blade of the rotor for separating a set of oil chambers other than the at least one set of oil chambers.

Preferably, the rotor includes a cylindrical rotor body and a plurality of the rotor blades projecting radially outward from the rotor body, the stator including a cylindrical stator body and extending radially inward from the stator body a plurality of stator protrusions, the rotor blades and the stator protrusions being alternately arranged in a circumferential direction to form the separation between the two adjacent stator protrusions by the rotor blade a first oil chamber and the second oil chamber, the communication passage being formed at a portion of the stator body between the adjacent two stator protrusions and having the communication passage at the stator body a first opening and a second opening that are open to the radially inner side, the first opening corresponding to the first oil chamber and the second opening corresponding to the second oil chamber in the locked state.

More preferably, in the locked state, the first opening can be closed by the rotor blade, and the second opening is always in an on state.

More preferably, a circumferential side of the at least one of the stator protrusions facing the second oil chamber is formed with a circumferential side protrusion protruding toward the second oil chamber, such that the locking The circumferential side protrusion is in contact with the rotor blade; and/or the other side of the at least one of the stator protrusions facing the first oil chamber is formed toward the first The axially convex portion on the other side of the oil chamber.

By adopting the above technical solution, the present invention provides a novel camshaft phaser that allows two oil chambers in at least one set of oil chambers of a camshaft phaser to communicate with each other in a locked state, such that There is oil in both of the at least one set of oil chambers. Thus, in the locked state, even if there is a slight relative rotation of the rotor relative to the stator due to the presence of the locking gap, the oil chambers on both sides of the rotor blade are oiled to buffer such minute rotation of the rotor. Thereby the resulting high frequency noise is eliminated.

DRAWINGS

1 is a schematic cross-sectional view of a prior art camshaft phaser showing the camshaft phaser in a locked state and wherein the black fill portion schematically shows the oil in the oil chamber.

2a is a cross-sectional view of a camshaft phaser in accordance with an embodiment of the present invention, showing the camshaft phaser in a locked state and wherein the black fill portion schematically shows the oil in the oil chamber; 2b and 2c are schematic cross-sectional views of the camshaft phaser of Fig. 2a, respectively showing the unlocked state of the camshaft phaser and wherein the black fill portion schematically shows the oil in the oil chamber.

Description of the reference numerals

1 stator 11 stator main body 12 stator projection portion 121 circumferential side projection 122 circumferential side projection on the other side 13 communication passage 131 first opening portion 131a first opening 132 connecting portion 133 second opening portion 133a second opening 14 single Direction valve 2 rotor 21 rotor body 22 rotor blade 23 second oil circuit 3 locking assembly 4 sealing assembly 5 connecting piece

A first oil chamber B second oil chamber C circumferential direction

detailed description

The technical solution of the present invention will be described below with reference to the accompanying drawings. The camshaft phaser according to the present invention has a substantially 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, respectively, unless otherwise specified. "Circumferential side" refers to the counterclockwise direction in Figures 2a to 2c; "the other side in the circumferential direction" refers to the clockwise direction in Figures 2a to 2c.

As shown in FIG. 2a, the basic structure of a camshaft phaser according to an embodiment of the present invention is the same as that of the prior art camshaft phaser shown in FIG. 1, and the structural difference between the two is the same. The camshaft phaser according to an embodiment of the present invention changes the structure of a group of oil chambers, which will be described in detail below.

As with the prior art camshaft phaser structure shown in Fig. 1, as shown in Fig. 2a, the camshaft phaser according to the present invention includes an end cap (not shown), a stator 1, a rotor 2, and a lock assembly. 3. The stator 1 is fixed to the end cover by a connecting member 5, the rotor 2 is disposed radially inward of the stator 1 and is rotatable relative to the stator 1, and the end cover, the rotor 2 and the stator 1 are formed to be distributed along the circumferential direction C. Four groups of oil chambers. More specifically, the stator 1 includes a stator body 11 and a plurality of stator protrusions 12, and the rotor 2 includes a rotor body 21 and a plurality of rotor blades 22. Each rotor blade 22 is located between two adjacent stator projections 12 such that the space between adjacent two stator projections 12 is separated by rotor blades 22 located between the two stator projections 12. The first oil chamber A and the second oil chamber B. Further, a seal assembly 4 that abuts against the stator main body 11 is provided at the tip end of the rotor blade 22. In the four groups of oil chambers formed in the camshaft phaser shown in FIG. 2, each group of oil chambers includes a first oil chamber A and a second oil chamber B, a first oil chamber A and a second oil chamber B. The oil supply means is connected to each other through an independent oil passage (only the second oil passage 23 communicating with the second oil chamber B is shown in the drawing).

In one aspect, for only one of the four sets of oil chambers (the set of oil chambers located above in Figure 2a), the stator 1 is formed with a communication passage 13 such that the camshaft phaser is in the rotor 2 locked assembly 3 The first oil chamber A and the second oil chamber B in the group of oil chambers are unidirectionally communicated through the communication passage 13 in a locked state in which the lock is not rotatable relative to the stator 1. A check valve 14 is disposed in the communication passage 13 to achieve a unidirectional conduction of the communication passage 13 so that the oil of the first oil chamber A can flow into the second oil chamber B in the locked state.

On the other hand, in the locked state, the second oil passage 23 corresponding to the second oil chamber B in the group of oil chambers is closed, so that the oil flowing from the first oil chamber A into the second oil chamber B can no longer pass the first The second oil passage 23 flows out. In the present embodiment, in the locked state, the radially outer opening of the second oil passage 23 is closed by the tip end of the stator protrusion portion 12 to be closed, so that the second oil passage 23 is closed, thereby being in the group of oil chambers. A predetermined amount of oil remains in the second oil chamber B.

Thus, by storing a certain amount of oil in both the first oil chamber A and the second oil chamber B, the rotor 2 has a slight relative rotation with respect to the stator 1 even in the locked state due to the presence of the lock gap. The oil in the first oil chamber A and the second oil chamber B can also buffer the rotation of the rotor 2, thereby preventing noise generated by the collision between the rotor 2 and the stator 1.

Specifically, the communication passage 13 is formed in a portion of the stator main body 11 between the adjacent two stator projections 12 and the communication passage 13 includes the first opening portion 131, the connecting portion 132, and the second opening portion that are sequentially connected. 133. The first opening portion 131, the connecting portion 132, and the second opening portion 133 each extend linearly. The first opening portion 131 forms a first opening 131a that opens radially inward on the radially inner side surface of the stator body 11, and the second opening portion 133 forms a second opening that opens toward the radially inner side on the radially inner side surface of the stator body 11. 133a, the check valve 14 is disposed at the connecting portion 132. In the locked state, the first opening 131a corresponds to the first oil chamber A and the second opening 133a corresponds to the second oil chamber B.

In the normal case, the first opening 131a causes the first opening portion 131 to communicate with the first oil chamber A. However, in the case where the pressure in the second oil chamber B is unexpectedly excessive or severely vibrated, the rotor blade 22 can be slightly opposed to the side of the first opening 131a due to the existence of the lock gap even in the locked state. Rotation, such that the radially outer side of the rotor blade 22 can close the first opening 131a when the locking gap is maximized, thereby preventing excessive oil from flowing from the first oil chamber A into the second oil chamber B via the communication passage 13.

In addition, the second opening 133a causes the second opening 133 to communicate with the second oil chamber B. Even if the pressure in the first oil chamber A is greater than the pressure in the second oil chamber B or the severe vibration, the second opening 133a is always in an on state. In this way, it is possible to ensure that a predetermined amount of oil remains in the second oil chamber B at all times.

In addition, in the locked state, in addition to the group of oil chambers in which the first oil chamber A and the second oil chamber B communicate with each other, the second oil passage 23 corresponding to the second oil chamber B in the other group of oil chambers is guided. The through state is such that oil from the oil supply device can flow into the second oil chamber B of the groups via the second oil passage 23 by controlling the oil supply device to be opened. Further, in the present embodiment, the lock assembly 3 corresponds to the rotor blade 22 of the rotor 2 for partitioning another set of oil chambers. Thus, the normal operation of the camshaft phaser is ensured without significantly changing the structure of the prior art camshaft phaser of FIG.

The structure of the camshaft phaser according to an embodiment of the present invention has been described above, and the operation of the camshaft phaser will be briefly described below.

As shown in FIG. 2a, when the camshaft phaser having the above structure is in the locked state shown in FIG. 1, the rotor 2 is locked by the lock assembly 3 so as not to be rotatable relative to the stator 1, and at this time, the first oil chamber A is in the state of the largest volume and the second oil chamber B is in the state of the smallest volume. At this time, the rotor blade 22 abuts on the circumferential side protrusion 121 formed toward the second oil chamber B formed on one circumferential side of the stator protrusion 12, so that the second oil chamber B can retain a predetermined minimum volume.

Figures 2b and 2c show schematic cross-sectional views of the camshaft phaser of Figure 2a, respectively, in an unlatched state. Starting from the locked state shown in FIG. 2a, after the second oil passage 23 continues to input oil to the second oil chamber B in the other group of oil chambers other than the group of oil chambers whose structure has been subjected to the above change, the lock assembly 3 After the unlocking is completed, the rotor 2 can rotate relative to the stator 1; as the oil pressure of the second oil chamber B increases, the oil pressure in the second oil chamber B is greater than the oil pressure in the first oil chamber A, so that the rotor 2 is relatively The stator 1 is sequentially rotated to the state in Figs. 2b and 2c to realize the phase modulation function of the camshaft phaser. As shown in FIGS. 2b and 2c, when the camshaft phaser is in the unlocked state, both openings of the communication passage 13 communicate with the second oil chamber B. Further, on the other side in the circumferential direction of the stator projection 12, a circumferential other side protrusion 122 that protrudes toward the first oil chamber A is formed, and in the state shown in Fig. 2c, the other side of the circumference is convex. 122 is for enabling the first oil chamber A to retain a predetermined minimum volume.

Although the above specific embodiments have explained the technical solutions of the present invention in detail, it is also necessary to explain that:

1. Without substantially changing the structure of the prior art camshaft phaser, in the camshaft phaser according to an embodiment of the present invention, only one set of oil chamber corresponding structures is performed. The changes as described above, but the invention is not limited thereto.

The structure of the plurality of sets of oil chambers can be varied as described above as needed. Even if necessary, the oil chambers of all groups can be changed as described above, as long as the normal operation of the camshaft phaser can be ensured.

2. Although not explicitly stated in the above specific embodiments, it should be understood that the circumferential side protrusion 121 and the circumferential side protrusion 122 may be provided only to one stator protrusion 12 or may be provided to a plurality of stators. Projection portion 12.

3. The oil supply device can continuously supply oil to the first oil chamber A through the first oil passage regardless of whether the camshaft phaser is in the locked state or the non-locked state.

4. Although the first opening portion 131, the connecting portion 132, and the second opening portion 133 are linearly extended in the above specific embodiments, the present invention is not limited thereto. For example, the first opening portion 131, the connecting portion 132, and the second opening portion 133 may extend in a curved shape to constitute a communication passage 13 that is entirely curved.

Claims

A camshaft phaser comprising a stator, a rotor and a lock assembly, the rotor being disposed radially inward of the stator and rotatable relative to the stator, the rotor and the stator Forming a plurality of sets of oil chambers distributed in a circumferential direction, each of the oil chambers including a first oil chamber and a second oil chamber separated by rotor blades of the rotor, wherein

The at least one of the plurality of sets of oil chambers is in a locked state in which the camshaft phaser is in a locked state in which the rotor is locked by the lock assembly relative to the stator The first oil chamber is electrically connected to the second oil chamber such that oil in the first oil chamber can flow into the second oil chamber in the locked state to retain a predetermined amount in the second oil chamber The oil.
The camshaft phaser according to claim 1, wherein said stator is formed with a communication passage, said first oil chamber and said first one of said at least one group of oil chambers in said locked state The two oil chambers are unidirectionally communicated through the communication passage.
The camshaft phaser according to claim 2, wherein a check valve is provided in the communication passage to make the communication passage unidirectional.
The camshaft phaser according to any one of claims 1 to 3, wherein the first oil chamber communicates with an oil supply device through a first oil passage formed in the rotor, the second oil a cavity is communicated with the oil supply device through a second oil passage formed in the rotor and spaced apart from the first oil passage, and

In the locked state, the second oil passage corresponding to the second oil chamber in the at least one set of oil chambers is closed such that flow from the first oil chamber into the second oil chamber Oil cannot flow out through the second oil passage.
A camshaft phaser according to claim 4, wherein in said locked state, a diameter of said second oil passage corresponding to said second oil chamber of said at least one group of oil chambers The outer opening is closed by the stator such that the second oil passage is closed.
A camshaft phaser according to claim 4 or 5, wherein in said locked state, corresponding to said second oil chamber in a group of oil chambers other than said at least one group of oil chambers The second oil passage is turned on such that oil from the oil supply device can flow into the second oil chamber via the second oil passage.
The camshaft phaser according to any one of claims 1 to 6, wherein the lock assembly is disposed at a portion of the rotor for separating a group of oil chambers other than the at least one group of oil chambers The rotor blade.
A camshaft phaser according to claim 2 or 3, wherein said rotor comprises a cylindrical rotor body and a plurality of said rotor blades projecting radially outward from said rotor body, said stator comprising a cylindrical stator body and a plurality of stator protrusions projecting radially inward from the stator body, the rotor blades and the stator protrusions being alternately arranged in a circumferential direction to protrude in two adjacent stators Forming the first oil chamber and the second oil chamber separated by the rotor blade between the portions,

The communication passage is formed at a portion of the stator main body between the adjacent two stator protrusions and the communication passage has a first opening and a second opening at a radially inner side surface of the stator main body An opening in which the first opening corresponds to the first oil chamber and the second opening corresponds to the second oil chamber.
A camshaft phaser according to claim 8 wherein:

In the locked state, the first opening can be closed by the rotor blade and the second opening is always in an on state.
A camshaft phaser according to claim 8 wherein:

a circumferential side of the at least one of the stator protrusions facing the second oil chamber is formed with a circumferential side protrusion protruding toward the second oil chamber, such that in the locked state a circumferential side raised portion abuts the rotor blade; and/or

The other side surface of the at least one of the stator protrusions facing the first oil chamber is formed with an axially opposite side protrusion that protrudes toward the first oil chamber.