Electrically conductive seal ring assembly and electric camshaft phaser
By replacing copper slip rings and brushes in the electric camshaft phase adjuster with conductive sealing ring assemblies, low-cost, reliable power supply and dynamic sealing are achieved, solving the problem of easy wear of copper slip rings and brushes, reducing maintenance costs and increasing service life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SCHAEFFLER HLDGCHINA
- Filing Date
- 2020-11-24
- Publication Date
- 2026-07-24
AI Technical Summary
In existing electric camshaft phase adjusters, copper slip rings and brushes are expensive and prone to wear, leading to frequent maintenance and increasing overall costs.
The conductive sealing ring assembly, including conductive sealing parts and insulating sealing parts distributed along the axis, forms multiple independent conductive paths, replacing copper slip rings and brushes, to achieve dynamic sealing and reliable power supply.
It reduces the cost of the motor and electric camshaft phase adjuster, reduces maintenance requirements, improves sealing performance and service life, and reduces structural size.
Smart Images
Figure CN114542229B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of vehicle technology. More specifically, it relates to a conductive sealing ring assembly for an electric camshaft phase adjuster and the electric camshaft phase adjuster itself. Background Technology
[0002] An electric camshaft phase adjuster is used to controllably adjust the phase relationship between the crankshaft and camshaft in an internal combustion engine. Compared to existing hydraulic camshaft phase adjusters, electric camshaft phase adjusters offer a wider operating range, higher phase shift speeds, and flexible timing control during engine start-up. In an electric camshaft phase adjuster, a first rotating member, typically configured as a sprocket, is driven by the engine's crankshaft via a chain, belt, or other form of transmission. A second rotating member is typically mounted anti-rotatingly at the end of the camshaft. The electric camshaft phase adjuster also includes a transmission connecting the first and second rotating members, and a motor that drives the second rotating member to deflect relative to the first rotating member by a predetermined phase via the transmission.
[0003] For example, the above-mentioned type of electric camshaft phase adjuster is disclosed in patent documents CN 102235194 B and CN 103806971 B. In the electric camshaft phase adjuster, the motor includes a stator fixed to a first rotating member and a rotor that can rotate relative to the stator and transmit rotational motion to a second rotating member. A coil disposed on at least one of the stator and rotor can cause the rotor to rotate relative to the stator when energized. In this embodiment, a copper slip ring and brushes are provided to supply power to the motor. The copper slip ring is disposed on the first rotating member and can supply power to the motor coils. The brushes are disposed on a cover arranged relative to the first rotating member, and the brushes abut against the copper slip ring.
[0004] However, in the above-mentioned scheme of powering the electric motor with copper slip rings and brushes, on the one hand, the cost of copper slip rings and brushes themselves is high, and on the other hand, because brushes are prone to wear, they need to be constantly maintained or replaced throughout the entire service life of the internal combustion engine, resulting in a high overall cost of the electric camshaft phase adjuster. Summary of the Invention
[0005] Therefore, the object of the present invention is to provide a power supply scheme for the motor in an electric camshaft phase adjuster, which can be implemented at a low cost while providing reliable power supply.
[0006] The above objective is achieved in one aspect of the present invention by a conductive sealing ring assembly. The conductive sealing ring assembly includes at least two conductive sealing rings distributed axially and interconnected, wherein each conductive sealing ring includes a conductive sealing portion and an insulating sealing portion distributed axially, and wherein the conductive sealing ring is configured with a sealing lip, wherein the sealing lip is jointly formed by the conductive sealing portion and the insulating sealing portion, and the sealing lip is capable of abutting against a member rotatable relative to the conductive sealing ring assembly (hereinafter referred to as the "relatively rotating member").
[0007] The conductive sealing ring assembly provided herein can provide dynamic sealing for relatively rotating components to prevent oil or dirt from entering the sealing area, such as inside a motor.
[0008] On the other hand, since each conductive sealing ring abuts against the relatively rotating member with its conductive sealing part, and the conductive sealing parts of different conductive sealing rings are electrically insulated from each other, multiple independent conductive paths for radial charge transmission can be established in the conductive sealing ring assembly along the axial direction. Thus, the conductive sealing ring assembly can be used to establish multiple independent conductive paths spaced apart along the axial direction between two nested members that can rotate relative to each other (i.e., the relatively rotating member and the relatively fixed member). Here, each sealing lip is preferably entirely composed of both a conductive sealing part and an insulating sealing part, thereby preventing electrical connection or short circuit between different conductive paths due to contact between the conductive sealing parts of adjacent sealing lips after the conductive sealing ring assembly is assembled.
[0009] In one embodiment, each conductive seal ring forms a sealing lip on its radially inner side. Here, the relative rotating member is configured as a shaft, such as a power supply shaft, capable of extending radially inward into the conductive seal ring assembly. This shaft has axially arranged electrodes that are mutually isolated in number and position relative to the respective conductive seal portions in the conductive seal ring assembly. Accordingly, the conductive seal ring assembly can be mounted, for example, on the rotor or stator of a motor, with each conductive seal ring in the assembly abutting its radially outer end against the axially isolated electrodes correspondingly disposed on the rotor or stator. Thus, after the conductive seal ring assembly is mounted in the motor, the shaft can provide a current of a predetermined intensity with different electrodes under the control of the motor controller, thereby driving the motor to operate in a predetermined manner. This eliminates the need for copper slip rings and brushes as in existing solutions, thereby reducing motor costs or the cost of the electric camshaft phase adjuster on which the motor is located. Furthermore, the conductive seal ring assembly itself has a small structural size and can be compactly arranged in the motor, thus the structural size of the motor or the electric camshaft phase adjuster on which the motor is located can be correspondingly reduced.
[0010] In a preferred embodiment, the conductive seal is made of conductive polytetrafluoroethylene (PTFE). Here, each conductive sealing ring abuts against the relatively rotating member using conductive PTFE. Because conductive PTFE has a very low coefficient of friction, the contact area of the sealing lips of each conductive sealing ring can be maximized, thereby ensuring the sealing performance of the conductive sealing ring assembly and the conductivity of each conductive path. Furthermore, even with a large contact area formed by the sealing lips of the conductive sealing rings, the resulting frictional torque is small, thus minimizing wear on the conductive sealing ring assembly during the service life of the motor or electric camshaft phase adjuster. In this case, both the sealing and conductivity performance of the conductive sealing ring assembly are ensured during the service life of the motor or electric camshaft phase adjuster, while also saving on maintenance or replacement costs, particularly for the conductive sealing ring assembly.
[0011] In a preferred embodiment, the insulating seal is made of insulating rubber, thereby enabling low-cost and reliable isolation between the various conductive paths.
[0012] In a preferred embodiment, a thin metal layer is arranged between the conductive sealing portion and the insulating sealing portion in the conductive sealing ring. Here, the thin metal layer can advantageously cooperate with the conductive sealing portion of the corresponding conductive sealing ring, preferably made of conductive PTFE, to form a conductive path, thereby enhancing the overall conductivity of each conductive sealing ring.
[0013] Advantageously, the thin metal layer has a mesh structure. That is, the thin metal layer can be implemented as a metal mesh structure. The flexible and thin metal mesh structure can provide good toughness, which is particularly beneficial for dynamic sealing applications.
[0014] In one advantageous embodiment, the sealing lip in the conductive sealing ring is constructed continuously along the circumferential direction. In this case, the conductive sealing ring assembly has strong sealing performance.
[0015] In another advantageous embodiment, the sealing lips in the conductive seal are configured at intervals along the circumferential direction. In this case, the conductive seal of the conductive seal assembly experiences less wear during use, thus resulting in a longer service life for the conductive seal assembly.
[0016] Optionally, the conductive sealing rings form a sealing lip on the radially inner side and are interconnected on the radially outer side. Alternatively, the conductive sealing rings form a sealing lip on the radially outer side and are interconnected on the radially inner side. Thus, the conductive sealing ring assembly can achieve dynamic sealing on either the radially inner or radially outer side depending on the specific motor design.
[0017] Advantageously, insulating material is provided at both ends of the sleeve portion formed by the interconnection of the various conductive sealing rings. Here, the conductive sealing ring assembly can be fixed to corresponding components in the motor, particularly by means of the sleeve portion. Since insulating material is provided at both ends of the sleeve portion, the conductivity of the conductive path located at the axial end side in the conductive sealing ring assembly can be ensured.
[0018] The above objective is achieved in another aspect of the invention by an electric camshaft phase adjuster. This electric camshaft phase adjuster includes a conductive sealing ring assembly constructed according to the above embodiment.
[0019] Here, the electric camshaft phase adjuster preferably includes a first rotating member and a second rotating member rotatable relative to each other, and a transmission device. Advantageously, the first rotating member is constructed as a sprocket and can be driven by the crankshaft of an internal combustion engine via a chain, belt, or other form of transmission device. Advantageously, the second rotating member can be mounted anti-rotatingly at the end of the camshaft. Advantageously, the transmission device is connected between the first rotating member and the second rotating member. The transmission device is, for example, constructed as a harmonic generator.
[0020] The electric camshaft phase adjuster also includes a motor. The motor drives a second rotating member to deflect relative to a first rotating member by a predetermined phase via a transmission mechanism. The motor, for example, includes a stator fixed to the first rotating member and a rotor rotatable relative to the stator and capable of transmitting rotational motion to the second rotating member, wherein coils disposed on at least one of the stator and rotor can cause the rotor to rotate relative to the stator when energized. The motor is, for example, configured as an axial flux motor or a radial flux motor.
[0021] The conductive sealing ring assembly according to the above embodiment can seal the motor relative to the outside, thereby preventing oil or dirt from entering the motor's interior. Furthermore, the conductive sealing ring assembly can establish a dynamic conductive path between the respective electrodes of the relatively rotating power supply shaft and the corresponding electrodes of the rotor or stator.
[0022] Therefore, the conductive sealing ring assembly provided here combines excellent sealing and conductivity. Furthermore, the conductive sealing ring assembly has a small structure and can be compactly arranged in the motor, thus saving significant installation space. In addition, the conductive sealing ring assembly also has the advantages of low cost and long service life. Attached Figure Description
[0023] Preferred embodiments of the present invention will now be illustrated schematically with reference to the accompanying drawings. The drawings are as follows:
[0024] Figure 1 This is a cross-sectional view of the conductive sealing ring assembly according to the first embodiment in the installed state;
[0025] Figure 2 It is based on Figure 1 A three-dimensional view of the conductive sealing ring assembly;
[0026] Figure 3 It is based on Figure 1 A partial perspective cross-sectional view of the conductive sealing ring assembly;
[0027] Figure 4 It is based on Figure 1 A schematic diagram of the conductive path of the conductive sealing ring assembly in the motor;
[0028] Figure 5 This is a cross-sectional view of the conductive sealing ring assembly according to the second embodiment in the installed state;
[0029] Figure 6 It is based on Figure 5 A perspective view of the conductive sealing ring assembly; and
[0030] Figure 7 It is based on Figure 5 A partial perspective cross-sectional view of the conductive sealing ring assembly. Detailed Implementation
[0031] Figure 1 A cross-sectional view of the conductive sealing ring assembly 3 according to the first embodiment in its installed state is shown. The conductive sealing ring assembly 3 according to this embodiment is applied to the motor in an electric camshaft phase adjuster. Figure 1 As shown, the conductive sealing ring assembly 3 is fixed to the rotor 1 of the motor via an interference fit on the radially outer side. The conductive sealing ring assembly 3 can slide relative to the power supply shaft 2 of the motor on the radially inner side.
[0032] Figure 2 It is shown that it is based on Figure 1 A perspective view of the conductive sealing ring assembly 3; Figure 3 It shows that according to Figure 1 A partial perspective cross-sectional view of the conductive sealing ring assembly 3. Combined with... Figure 2 and Figure 3 As can be seen, in this embodiment, the conductive sealing ring assembly 3 has nine conductive sealing rings that are distributed axially and interconnected. In other embodiments, the conductive sealing ring assembly may have an additional number of conductive sealing rings.
[0033] Especially Figure 3As shown, each conductive sealing ring includes a conductive sealing portion 32, a thin metal layer 33, and an insulating sealing portion 31 arranged sequentially along the axial direction. The conductive sealing portion 32, the thin metal layer 33, and the insulating sealing portion 31 extend together from the radially inner side to the radially outer side of each conductive sealing ring. Here, in the conductive sealing ring assembly, the conductive sealing portion 32, the thin metal layer 33, and the insulating sealing portion 31 can be arranged in a cyclical manner. The insulating sealing portion 31 is made of insulating rubber. The conductive sealing portion 32 is made of conductive PTFE. The thin metal layer 33 arranged between the conductive sealing portion 32 and the insulating sealing portion 31 has a mesh structure; the soft and thin metal mesh structure provides good toughness, which is particularly beneficial for dynamic sealing. The combination of the thin metal layer 33 and the conductive sealing portion 32 can advantageously enhance the conductivity of the radially conductive path of each conductive sealing ring. The conductive sealing ring assembly 3 constructed in this way can reliably and cost-effectively achieve dynamically conductive paths that are mutually isolated in the axial direction.
[0034] In this embodiment, each conductive sealing ring forms a sealing lip on its radially inner side, and the sealing lip is continuously constructed along the circumferential direction. Each conductive sealing ring abuts against the outer peripheral surface of the power supply shaft 2 with a conductive sealing part 32 made of conductive PTFE, and forms a dynamic seal relative to the power supply shaft 2 when the electric camshaft phase adjuster is running.
[0035] In this embodiment, the conductive sealing rings are interconnected radially outward. Both ends of the sleeve portion formed by the interconnection of the conductive sealing rings are provided with insulating material 34 in the form of insulating rubber. Here, the conductive sealing ring assembly 3 is fixed to the rotor 1 in the motor via the sleeve portion.
[0036] Figure 4 It shows that according to Figure 1 A schematic diagram of the conductive path of the conductive sealing ring assembly 3 in the motor. (See diagram below.) Figure 4 As shown on the left, for example, the power supply shaft 2 supported on the sprocket cover has axially arranged electrodes that are mutually isolated in number and position from the individual conductive seals in the conductive seal assembly 3. Accordingly, as... Figure 4 As shown on the right, electrodes that are axially isolated are correspondingly arranged at the mounting positions of the conductive sealing ring assembly 3 on rotor 1. Thus, when the electric camshaft phase adjuster is running, the power supply shaft 2 can provide current of a predetermined intensity to different electrodes under the control of the motor controller, thereby driving the motor to operate in a predetermined manner.
[0037] Figure 5 A cross-sectional view of the conductive sealing ring assembly 4 according to the second embodiment in the installed state is shown. Figure 6 It shows that according to Figure 5 A perspective view of the conductive sealing ring assembly 4. Figure 7 It shows that according to Figure 5A partial perspective cross-sectional view of the conductive sealing ring assembly 4.
[0038] Combination Figures 5 to 7 As can be seen, the conductive sealing ring assembly 4 is constructed similarly to the conductive sealing ring assembly 3 of the previous embodiment. Here, each conductive sealing ring also includes a conductive sealing portion 42, a thin metal layer 43, and an insulating sealing portion 41 distributed sequentially along the axial direction.
[0039] In this embodiment, each conductive sealing ring forms a sealing lip on its radially inner side, and the sealing lips are spaced apart along the circumferential direction. In this configuration, the conductive sealing rings of the conductive sealing ring assembly 4 experience less wear during use, thus resulting in a longer service life for the conductive sealing ring assembly 4.
[0040] By means of the conductive sealing ring assemblies 3 and 4 according to the above embodiments, an axially independent radially conductive path for transmitting charge can be established between the rotor 1 and the power supply shaft 2, which rotate relative to each other, thereby supplying power to the motor. This eliminates the need for copper slip rings and brushes as in existing solutions, thus reducing the cost of the motor or the electric camshaft phase adjuster in which the motor is located. Furthermore, the conductive sealing ring assemblies 3 and 4 themselves have a small structural size and can be compactly arranged in the motor; therefore, the structural size of the motor, or the electric camshaft phase adjuster in which the motor is located, can be correspondingly reduced.
[0041] The conductive sealing ring assemblies 3 and 4 provided herein also provide dynamic sealing relative to the power supply shaft 2 to prevent oil or dirt from entering the motor. Because conductive PTFE has a very low coefficient of friction, the contact area between the sealing lips of each conductive sealing ring in the conductive sealing ring assemblies 3 and 4 and the power supply shaft 2 can be maximized, thereby ensuring the sealing performance of the conductive sealing ring assemblies 3 and 4. Furthermore, even with a large contact area formed by the sealing lips of the conductive sealing rings, the resulting frictional torque is small, thus minimizing wear on the conductive sealing ring assemblies 3 and 4 during the service life of the motor or electric camshaft phase adjuster. In this way, on the one hand, the sealing and conductive performance of the conductive sealing ring assemblies 3 and 4 are ensured during the service life of the motor or electric camshaft phase adjuster, and on the other hand, maintenance or replacement costs, especially for the conductive sealing ring assemblies 3 and 4, are saved.
[0042] While possible embodiments have been described exemplarily in the foregoing description, it should be understood that numerous variations of embodiments exist through combinations of all known and readily conceived technical features and implementation methods. Furthermore, it should be understood that the exemplary embodiments are merely examples and do not in any way limit the scope, application, or construction of the invention. The foregoing description is more intended to provide those skilled in the art with technical guidance for transforming at least one exemplary embodiment, wherein various changes can be made, particularly regarding the function and structure of the components, without departing from the scope of the claims.
[0043] List of reference numerals
[0044] 1. The rotor of the motor
[0045] 2. Components, power supply shaft
[0046] 3. Conductive sealing ring assembly
[0047] 31 Insulating sealing part
[0048] 32 Conductive sealing part
[0049] 33 Thin metal layer
[0050] 34 Insulation materials
[0051] 4. Conductive sealing ring assembly
[0052] 41 Insulating sealing part
[0053] 42 Conductive sealing part
[0054] 43 Thin metal layer
[0055] 44 Insulation materials
Claims
1. A conductive sealing ring assembly (3; 4), said conductive sealing ring assembly (3; 4) comprising at least two conductive sealing rings distributed axially and interconnected. in, The conductive sealing ring includes conductive sealing portions (32; 42) and insulating sealing portions (31; 41) distributed axially, and The conductive sealing ring is configured with a sealing lip, wherein the sealing lip is jointly formed by the conductive sealing part (32; 42) and the insulating sealing part (31; 41), and the sealing lip can abut against a member (2) that is rotatable relative to the conductive sealing ring assembly (3; 4) with the conductive sealing part (32; 42).
2. The conductive sealing ring assembly (3; 4) according to claim 1, wherein, The conductive sealing part (32; 42) is made of conductive polytetrafluoroethylene.
3. The conductive sealing ring assembly (3; 4) according to claim 1, wherein, The insulating sealing parts (31; 41) are made of insulating rubber.
4. The conductive sealing ring assembly (3; 4) according to claim 1, wherein, In the conductive sealing ring, a thin metal layer (33; 43) is arranged between the conductive sealing portion (32; 42) and the insulating sealing portion (31; 41).
5. The conductive sealing ring assembly (3; 4) according to claim 4, wherein, The thin metal layers (33; 43) have a mesh structure.
6. The conductive sealing ring assembly according to claim 1, wherein, In the conductive sealing ring, the sealing lip is constructed continuously along the circumferential direction.
7. The conductive sealing ring assembly according to claim 1, wherein, In the conductive sealing ring, the sealing lips are constructed at intervals along the circumferential direction.
8. The conductive sealing ring assembly (3; 4) according to claim 1, wherein, The conductive sealing rings form the sealing lip on the radially inner side and are interconnected on the radially outer side, or the conductive sealing rings form the sealing lip on the radially outer side and are interconnected on the radially inner side.
9. The conductive sealing ring assembly (3; 4) according to claim 8, wherein, Insulating material is provided at both ends of the sleeve portion formed by the interconnection of various conductive sealing rings.
10. An electric camshaft phase adjuster comprising a conductive sealing ring assembly (3; 4) according to any one of claims 1 to 9.