CN117940656A

CN117940656A - Phase adjuster for a camshaft

Info

Publication number: CN117940656A
Application number: CN202180101722.4A
Authority: CN
Inventors: 盛慧芳; 全婷
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2021-11-08
Filing date: 2021-11-08
Publication date: 2024-04-26
Also published as: WO2023077529A1

Abstract

A phase adjuster for a camshaft (4), comprising: a stator (1) having a ring-like structure; a rotor (2) which is accommodated in the stator (1) and forms a first pressure chamber and a second pressure chamber with the stator (1), the rotor (2) having an inlet channel (23), the first pressure chamber and the second pressure chamber being loadable with pressure fluid from the inlet channel (23) in order to be able to adjust the rotor (2) relative to the stator (1) about the axis of rotation (X); and an adapter (3) which is interposed between the rotor (2) and the camshaft (4) and which connects the rotor (2), the adapter (3) and the camshaft (4) in a rotationally fixed manner.

Description

Phase adjuster for a camshaft

Technical Field

The present application relates to the technical field of variable valve timing systems. More particularly, the present application relates to a phase adjuster for a camshaft.

Background

A variable valve timing system of an engine includes a phase adjuster for adjusting a rotational phase of a camshaft relative to a crankshaft. Fig. 1 shows one possible phase adjuster. As shown in fig. 1, the phase adjuster includes a stator 1', a rotor 2', and a control valve 3'. The control valve 3' is fitted into the rotor 2', one end of the control valve 3' is pressed against the end face of the rotor 2', and the other end is connected to the camshaft 4' by a screw. The various working parts of the control valve 3' are contained inside the housing 32' of the control valve 3'. The three-position four-way valve is realized by controlling the stroke of the piston 31 'of the valve 3'. And a casting assembly 5 'of a woven filter screen and a one-way valve is arranged at the oil inlet of the control valve 3', so that the effects of filtering impurities and one-way oil inlet are realized.

For the fastening connection with the camshaft 4' and the assembly of the loose parts together, the outer part of the control valve 3' is assembled with a housing 32 '. In order to achieve lateral oil distribution, an overmolded sleeve 33 'is used in the middle of the control valve 3'. To achieve filtration of impurities and one-way oil intake, a cast assembly 5' of woven screen and one-way valve is used. However, the process of the housing 32', sleeve 33' together with the filter screen and one-way valve assembly 5' is cumbersome and expensive. In addition, the rotor 2' is required to support the camshaft 4', and the manufacturability of the rotor 2' is poor and the cost is high.

Disclosure of Invention

The object of the present application is to provide a phase adjuster for a camshaft with reduced costs.

The present application provides a phase adjuster for a camshaft, comprising: a stator having a ring-like structure; a rotor housed within the stator and forming with the stator a first pressure chamber and a second pressure chamber, the rotor having an introduction passage, the first pressure chamber and the second pressure chamber being capable of being loaded with pressure fluid from the introduction passage to enable adjustment of the rotor relative to the stator about an axis of rotation; and the adapter is clamped between the rotor and the cam shaft and is connected with the rotor, the cam shaft and the adapter in a relatively rotation-proof way.

According to an embodiment of the application, the rotor, the adapter and the camshaft are connected by means of a bolt, one end of which passes through the rotor and the adapter and into the camshaft.

According to an embodiment of the present application, the phase adjuster further includes: a one-way valve; and a filter, wherein the check valve and the filter are interposed between the rotor and the adapter, or the check valve and the filter are interposed between the adapter and the camshaft.

According to an embodiment of the application, the adapter comprises a body part and an annular flange extending from the body part in a direction in which the camshaft is located, the first end of the camshaft extending into a space defined by the body part and the annular flange such that an inner side surface of the annular flange abuts radially inwardly against an outer peripheral surface of the first end of the camshaft and an end surface of the first end of the annular flange abuts against the body part.

According to an embodiment of the application, the adapter comprises a projection which projects in the direction of the rotation axis from the main body part towards the camshaft and projects into the interior of the camshaft.

According to an embodiment of the application, the body portion is plate-shaped.

According to an embodiment of the application, the body portion is provided with an oil inlet, which adjoins the protruding portion.

According to an embodiment of the application, the rotor has a central bore extending in the direction of the rotation axis, the phase adjuster further comprising a control valve for controlling the flow of the pressure fluid and comprising: a piston which is sleeved in the central hole and can reciprocate in the central hole along the direction of the rotation axis; and an elastic member interposed between the piston and the adapter member and capable of being elongated or shortened according to the reciprocating movement of the piston.

According to an embodiment of the present application, a side of the adapter facing the elastic member is concavely formed with an annular receiving portion to receive an end portion of the elastic member therein.

In the phase adjuster, the adapter is interposed between the rotor and the camshaft, and the rotor, the adapter, and the camshaft are connected in a rotationally fixed manner. And an adapter is used between the rotor and the cam shaft, and the manufacturing difficulty of the adapter is small, so that the cost is reduced.

Drawings

Fig. 1 is a cross-sectional view of one possible phase adjuster.

Fig. 2a and 2b are cross-sectional views of a phase adjuster according to an embodiment of the present application, respectively.

Fig. 3 is a partial cross-sectional view of a phaser according to one embodiment of the present application.

Fig. 4a and 4b are exploded views of a phase adjuster according to an embodiment of the present application, respectively.

Fig. 5a is a perspective view of a rotor according to an embodiment of the present application, fig. 5b and 5c are plan views of the rotor of fig. 5a, and fig. 5d is a cross-sectional view of the rotor of fig. 5a, respectively.

Fig. 6a and 6b are plan views of an adapter according to one embodiment of the application, respectively.

Fig. 7a to 7c are perspective, plan and sectional views, respectively, of a check valve according to an embodiment of the present application.

Fig. 8 is a plan view of a filter according to one embodiment of the application.

Fig. 9a to 9c are cross-sectional views of a phase adjuster according to an embodiment of the present application in a first position, a second position and a third position, respectively.

Detailed Description

Specific embodiments according to the present application will be described below with reference to the accompanying drawings. The following detailed description and the accompanying drawings are provided to illustrate the principles of the application and not to limit the application to the preferred embodiments described, the scope of which is defined by the claims.

The phase adjuster is mounted on an axial end of a camshaft of the engine. Fig. 2a and 2b are respectively cross-sectional views of a phase adjuster according to an embodiment of the present application, fig. 3 is a partial cross-sectional view of a phaser according to an embodiment of the present application, and fig. 4a and 4b are respectively exploded views of a phase adjuster according to an embodiment of the present application. As shown in fig. 2a to 4b, the phase adjuster includes a stator 1, a rotor 2, and an adapter 3. The stator 1 may be connected to a crankshaft of the engine, be of annular configuration and comprise an inner space for receiving the rotor 2. The rotor 2 is accommodated in the stator 1 and is reciprocally rotatable with respect to the stator 1 about a rotational axis X at a rotational angle to enable adjustment of a phase angle of the camshaft 4 with respect to the crankshaft.

Fig. 5a is a perspective view of a rotor according to an embodiment of the present application, fig. 5b and 5c are plan views of the rotor of fig. 5a, and fig. 5d is a cross-sectional view of the rotor of fig. 5a, respectively. As shown in fig. 5a to 5d, the rotor 2 includes a cylindrical body 21 and blades 22, and the blades 22 protrude radially outward from the outer peripheral wall of the body 21. A plurality of first pressure chambers and a plurality of second pressure chambers are formed between the stator 1 and the rotor 2. The centre of the rotor 2 has a central aperture 24 for receiving a control valve 9 (described below). The rotor 2 further comprises an introduction channel 23 through which introduction channel 23 pressurized fluid can enter into a central bore 24 of the rotor 2. In one example, the lead-in channel 23 includes a first channel 231 and a second channel 232 that intersect. The first passage 231 extends inward in the direction of the rotation axis X from the end of the rotor 2 facing the camshaft 4, and the second passage 232 extends inward in the radial direction. In one example, the number of the introduction passages 23 is four, and are uniformly spaced in the circumferential direction of the rotor 2. The first and second pressure chambers can be pressurized with a pressure fluid to enable an adjustment of the rotor 2 relative to the stator 1 about the rotation axis X. The body 21 of the rotor 2 further comprises a first opening 25 and a second opening 26 extending radially therethrough, the pressure fluid in the central bore 24 being able to flow into the first pressure chamber via the first opening 25 and the pressure fluid in the central bore 24 being able to flow into the second pressure chamber via the second opening 26.

The adapter 3 is clamped between the rotor 2 and the cam shaft 4, and the rotor 2, the adapter 3 and the cam shaft 4 are connected in a relatively rotation-proof manner. In the related art, the rotor supports the camshaft, however, manufacturability of the rotor is poor. In the application, the adapter is used between the rotor and the cam shaft, and the manufacturing difficulty of the adapter is small, so that the cost is reduced.

Fig. 6a and 6b are plan views of an adapter according to one embodiment of the application, respectively. As shown in fig. 6a and 6b, the adapter 3 includes a main body portion 30 and an annular flange 31 extending from the main body portion 30 toward the direction in which the camshaft 4 is located, the first end portion of the camshaft 4 extends into a space defined by the main body portion 30 and the annular flange 31 such that an inner side surface of the annular flange 31 abuts radially inward against an outer peripheral surface of the first end portion of the camshaft 4, and an end surface of the first end portion of the annular flange 31 abuts against the main body portion 30 to restrict movement of the camshaft 44 in the radial direction. For example, the body 30 has a plate shape. The adapter 3 includes a protruding portion 32, the protruding portion 32 protruding from the main body portion 30 in the direction of the rotation axis X toward the camshaft 4 and protruding into the interior of the camshaft 4. For example, the protruding portion 32 has a cylindrical shape. The body portion is provided with an oil inlet 33, the oil inlet 33 being adjacent to the protruding portion 32. In one example, the adapter 3 includes a plurality (e.g., four) of oil inlets 33, the plurality of oil inlets 33 being arranged at intervals along the circumferential direction of the adapter 3.

In one embodiment, bolts 5 are used to connect the rotor 2, adapter 3 and camshaft 4. Specifically, the threaded end of the bolt 5 passes through the rotor 2 and the adapter 3 and into the camshaft 4, and the head of the bolt 5 presses against the axial end face of the rotor 2. In one example, the number of bolts 5 is four, and are uniformly spaced in the circumferential direction of the rotor 2.

The phase adjuster further comprises a first end cap 10 on the side facing the camshaft 4 and a second end cap 20 on the side facing away from the camshaft 4, and serves to sandwich the rotor 2 and the adapter 3 therebetween. The outside of the first end cap 10 is provided with a spiral spring which contracts when the rotor 2 rotates in one direction with respect to the stator 1. After the rotor 2 rotates to a set angle to realize the optimal air distribution phase, the rotor 2 can rotate in the opposite direction relative to the stator 1 under the action of the restoring force of the spiral spring, so that the resetting is realized.

Referring back to fig. 4b, the rotor 2 and the adapter 3 are further connected by a pin 6, and the pin 6 is in interference fit with the rotor 2 and the adapter 3 respectively, so as to prevent the rotor 2 and the adapter 3 from rotating relatively. The rotor 2 and the adapter 3 are fixed through the pin 6, the assembly mode is simple, and no extra cost is generated. In one example, the number of pins 6 is two, and two pins 6 are provided at opposite ends of the rotor 2 in the same radial direction, respectively. One of the pins 6, known as a support pin, passes through the rotor 2 and the first end cap 10 for supporting the spiral spring.

The phase adjuster further includes a check valve 7 and a filter 8, and the check valve 7 and the filter 8 are interposed between the rotor 2 and the adapter 3 or the check valve 7 and the filter 8 may be interposed between the adapter 3 and the camshaft 4. In one example, the rotor 2, the check valve 7, the filter 8, the adapter 3 and the camshaft 4 are arranged in this order. In the application, the one-way valve and the filter are clamped between the rotor and the adapter, and an additional fixing mode is not needed, so that the assembly of the one-way valve and the filter is simplified, and the production cost is reduced.

Fig. 7a to 7c are perspective, plan and sectional views, respectively, of a check valve according to an embodiment of the present application. As shown in fig. 7a to 7c, the check valve 7 is in a flat sheet shape and includes a fixed portion 71 and a movable portion 72. The fixing portion 71 has an opening 711, and the opening 711 is provided corresponding to the introduction passage 23. The fixed portion 71 also has a first central hole 73 for the passage of a piston 91 (described below) of the control valve 9. The movable portion 72 is connected to the fixed portion 71, and is provided corresponding to the opening 711. The movable portion 72 is movable to a closed position and an open position. In the closed position, the movable portion 72 is positioned within the opening 711 to close the opening 711. In this position, the pressure fluid cannot flow into the rotor 2 through the opening 711. In the open position, the movable portion 72 is tilted from the plane in which the fixed portion 71 is located in a direction away from the camshaft 4, so that the pressure fluid can flow into the introduction passage 23 through the opening 711. The check valve 7 has a first side facing the camshaft 4, and the filter 8 abuts against the check valve 7 at the first side so that the restricting movable portion 72 is tilted toward the direction in which the camshaft 4 is located, whereby the check valve 7 performs a function of unidirectionally transmitting the pressure fluid. The outline of the movable portion 72 matches the shape of the opening 711.

In one example, the movable portion 72 is configured to have a substantially V-shape. The V-shape not only maximizes the utilization of space, but also ensures that the oil is opened at a minimum pressure. The number of the openings 711 and the movable portions 72 is matched to the number of the introduction passages 23, for example, four. The V-shaped movable portion 72 includes a first extension 721 and a second extension 722 connected to each other with an acute angle therebetween. The free end of the first extension 721 is connected to the fixed portion 71, and the second extension 722 is arranged adjacent to the second central hole 82 and conforms to the profile of the second central hole 82.

Referring back to fig. 3, on the side facing the one-way valve 7, the introduction channel 23 of the rotor 2 is designed to adapt to the shape of the movable part 72 such that the movable part 72 of the one-way valve 7 is tilted unhindered in the direction away from the camshaft 4.

Fig. 8 is a plan view of a filter according to one embodiment of the application. As shown in fig. 8, the filter 8 has a flat sheet shape and includes an annular filter area 81, and the oil inlet 33 of the adapter 3, the filter area 81, and the movable portion 72 of the check valve 7 are disposed in correspondence. The filtering area 81 is constructed in a mesh structure formed by an etching process. For example, the filter 8 is made of metal (e.g., steel sheet). The thickness of the check valve 7 and the filter 8 may be 0.5mm or less, taking up little axial space. The filter 8 only needs to etch the filter holes in the filter area 81, so that the process flexibility is high and the cost is low. The filter 8 is constructed of a complete metal and has a lifetime that is superior to prior art woven screens. The annular structure is simple in design, the corrosion area is as small as possible under the condition of ensuring oil inlet, and the manufacturing cost is saved. The filter 8 has a second central bore 82 for the passage of a piston 91 (described below) of the control valve 9.

Referring back to fig. 3, the rotor 2 has a central hole 24 penetrating in the direction of the rotation axis X. The phase adjuster further comprises a control valve 9, the control valve 9 being for controlling the flow of the pressure fluid and comprising a piston 91 and an elastic member 92. The piston 91 is fitted in the center hole 24 and is reciprocally movable in the center hole 24 in the direction of the rotation axis X. The elastic member 92 is interposed between the piston 91 and the adapter 3, and can be extended or shortened with the reciprocating movement of the piston 91. For example, the elastic member 92 is a coil spring. An electromagnet or other force application mechanism is provided on the side of the piston 91 facing away from the spring 92, the electromagnet being capable of generating an axial magnetic force on the piston 91. The piston 91 can reciprocate under the combined action of the elastic force of the elastic member 92 and the magnetic force of the electromagnet. The side of the adapter 3 facing the elastic element 92 is concavely formed with an annular receiving portion to receive the end of the elastic element 92 therein.

The outer peripheral wall of the piston 91 is in direct contact with the inner wall of the central bore 24. Compared with the prior art, the control valve omits the shell and the sleeve, so that the phase regulator has simple structure and reduced cost.

The piston 91 is configured in a cylindrical shape, and an end of the piston 91 facing the adapter 3 has an introduction port 911. The piston 91 has an outlet port 912 provided in the peripheral wall thereof, and the outlet port 912 is configured to discharge the pressure fluid to the control valve 9. The outer peripheral wall of the piston 91 is formed with a through groove 913 recessed radially inward to circumferentially surround the piston 91.

Fig. 9a to 9c are cross-sectional views of a phase adjuster according to an embodiment of the present application in a first position, a second position and a third position, respectively. As shown in fig. 9a to 9c, in the case where the piston 91 moves to the first position with respect to the rotor 2, the introduction passage 23 is communicated with the first pressure chamber through the introduction groove 913 and via the first opening 25, and the second pressure chamber is communicated with the introduction port 912 through the introduction port 911, so that the pressure fluid enters the first pressure chamber and the pressure fluid in the second pressure chamber flows out. In the case of a movement of the piston 91 into the second position relative to the rotor 2, the inlet channel 23 is connected to the second pressure chamber via the connecting channel 913 and via the second opening 26, and the first pressure chamber is connected to the outlet 912, so that the pressure fluid enters the second pressure chamber and the pressure fluid in the first pressure chamber flows out. In the case where the piston 91 moves to the third position with respect to the rotor 2, the introduction passage 23 is not communicated with either of the first pressure chamber and the second pressure chamber. In this case, the pressures in the first pressure chamber and the second pressure chamber are equal.

The control valve 9 further comprises a snap spring 93, which snap spring 93 is arranged at the end of the piston 91 facing away from the spring 92 and acts as a limit for limiting the reciprocating movement of the piston 91 in the direction of the rotation axis X.

As described above, although the exemplary embodiments of the present application have been described in the specification with reference to the accompanying drawings, the present application is not limited to the above-described specific embodiments, and the scope of the present application should be defined by the claims and their equivalents.

List of reference numerals

Stator 1, 1'

Rotor 2, 2'

Control valve 9, 3'

Pistons 91, 31'

Housing 32'

Sleeve 33'

Camshaft 4, 4'

Assembly 5'

First end cap 10

Second end cap 20

Body 21

Blade 22

Introduction channel 23

First channel 231

Second channel 232

Central bore 24

First opening 25

Second opening 26

Axis of rotation X

Adapter 3

Body portion 30

Annular flange 31

Protrusion 32

Oil inlet 33

Bolt 5

Pin 6

Check valve 7

Fixing portion 71

Opening 711

Movable portion 72

First extension 721

Second extension 722

First central hole 73

Filter 8

Filtration zone 81

Second central bore 82

Inlet 911

Outlet 912

Conduction groove 913

Elastic member 92

Clamp spring 93

Claims

A phase adjuster for a camshaft (4), comprising:

A stator (1) having a ring-like structure;

A rotor (2) housed within the stator (1) and forming with the stator (1) a first pressure chamber and a second pressure chamber, the rotor (2) having an introduction channel (23), the first and second pressure chambers being loadable with pressure fluid from the introduction channel (23) so as to be able to adjust the rotor (2) with respect to the stator (1) about an axis of rotation (X); and

And the adapter piece (3) is clamped between the rotor (2) and the cam shaft (4), and the rotor (2), the cam shaft (4) and the adapter piece (3) are connected in a relatively rotation-proof way.
The phase adjuster according to claim 1, wherein,

The rotor (2), the adapter (3) and the camshaft (4) are connected by a bolt (5), and one end of the bolt (5) passes through the rotor (2) and the adapter (3) and into the camshaft (4).
The phase adjuster of claim 1, further comprising:

A one-way valve (7); and

And the filter (8), wherein the one-way valve (7) and the filter (8) are clamped between the rotor (2) and the adapter (3), or the one-way valve (7) and the filter (8) are clamped between the adapter (3) and the cam shaft (4).
The phase adjuster according to claim 1, wherein,

The adapter (3) comprises a main body part (30) and an annular flange (31) extending from the main body part (30) towards the direction in which the camshaft (4) is located, a first end of the camshaft (4) extends into a space defined by the main body part (30) and the annular flange (31) such that an inner side surface of the annular flange (31) abuts radially inwardly against an outer peripheral surface of the first end of the camshaft (4), and an end surface of the first end of the camshaft (4) abuts against the main body part (30).
The phase adjuster according to claim 4, wherein,

The adapter (3) comprises a projection (32), which projection (32) protrudes in the direction of the rotational axis (X) from the body part (30) in the direction of the camshaft (4) and protrudes into the interior of the camshaft (4).
The phase adjuster according to claim 4, wherein,

The main body (30) is plate-shaped.
The phase adjuster according to claim 5, wherein,

An oil inlet (33) is formed in the main body portion (30), and the oil inlet (33) is adjacent to the protruding portion (32).
The phase adjuster according to claim 1, wherein,

The rotor (2) has a central bore (24) passing through in the direction of the rotation axis (X), the phase adjuster further comprising a control valve (9), the control valve (9) being for controlling the flow of the pressure fluid and comprising:

A piston (91) which is fitted in the central hole (24) and can reciprocate in the direction of the rotation axis (X) in the central hole (24); and

An elastic member (92) interposed between the piston (91) and the adapter (3) and capable of being extended or contracted with the reciprocating movement of the piston (91).
The phase adjuster according to claim 8, wherein,

The side of the adapter (3) facing the elastic element (92) is concavely formed with an annular receiving part to receive the end of the elastic element (92) therein.