Electrically excited electric machines, powertrains and electric vehicles

Abstract

This application provides an electrically excited motor, a powertrain, and an electric vehicle, relating to the field of electrically excited motor technology, and addresses the problem of excessive brush wear caused by long-term contact between the brush and the slip ring. The rotor shaft of the electrically excited motor passes through the central hole of the rotor, and the rotor windings of the rotor are connected to the slip rings of the electrically excited motor. The electrically excited motor includes multiple brushes and a drive mechanism. Each brush is used to contact the slip ring and provide excitation current to the rotor windings through the slip ring. During excitation, the drive mechanism drives at least one brush to move towards the slip ring until it contacts the slip ring, thereby providing excitation current to the rotor windings through the slip ring. When excitation is not required, the drive mechanism drives at least one brush to move away from the slip ring until it separates from the slip ring, thereby reducing brush wear caused by long-term contact between the brush and the slip ring and extending the service life of the brush.

Description

Technical Field

[0001] This application relates to the field of electric excitation motor technology, and more particularly to an electric excitation motor, powertrain, and electric vehicle. Background Technology

[0002] Electrically excited motors are widely used in vehicle drive systems due to their advantages such as high speed and power, good power factor, no use of magnets, overall performance superior to asynchronous motors, lower cost than permanent magnet synchronous motors, efficiency between permanent magnet synchronous and asynchronous motors, and the ability to shut off the rotor magnetic field. In an electrically excited motor, a magnetic field is generated by energizing the rotor through the contact between brushes and slip rings. However, in practical applications, it has been found that wear and tear on the contact between the brushes and slip rings leads to short brush life and high drag losses, thus limiting the application of electrically excited motors. Summary of the Invention

[0003] This application provides an electrically excited motor, a powertrain, and an electric vehicle to improve brush wear caused by long-term contact between the brush and the slip ring.

[0004] To achieve the above objectives, this application adopts the following technical solution: A first aspect of this application provides an electrically excited motor, the rotor shaft of which passes through a central hole in the rotor. The rotor windings of the rotor are connected to slip rings of the electrically excited motor. The electrically excited motor includes a plurality of brushes and a drive mechanism. Each brush is used to contact the slip rings and provide excitation current to the rotor windings through the slip rings. The drive mechanism is used to drive at least one brush to move toward the slip rings to contact them and to drive at least one brush away from the slip rings to separate from them.

[0005] In the electrically excited motor disclosed in this application, a drive mechanism drives the brushes to move, thereby changing the position of the brushes and enabling on-demand contact and separation between the brushes and the slip rings. When excitation is required, the drive mechanism drives at least one brush to move towards the slip ring until it contacts the slip ring. The external excitation current is transmitted to the rotor windings through the brushes and the rotating slip rings, thus providing excitation current to the rotor windings. When excitation is not required, the drive mechanism drives at least one brush to move away from the slip ring until it separates from the slip ring. The brushes and slip rings do not contact each other, thereby reducing brush wear caused by long-term contact between the brushes and the slip rings and extending the service life of the brushes.

[0006] In one embodiment, a drive mechanism is used to drive at least one brush to move toward or away from the slip ring along a first direction. The first direction is either the axial or radial direction of the rotor.

[0007] In some scenarios, at least one brush is located on one side of the slip ring along the radial direction of the rotor. The drive mechanism is used to drive the at least one brush to move toward or away from the slip ring along the radial direction of the rotor. The contact area between the brush and the slip ring is large and continuous, preventing the brush from sliding out of the slip ring along the axial direction of the rotor, so as to ensure the contact stability between the brush and the slip ring for reliable transmission of excitation current.

[0008] In some scenarios, the slip ring and multiple brushes are located on the outer periphery of the rotor shaft, and at least one brush is located on one side of the slip ring along the rotor axis. The drive mechanism is used to drive the at least one brush to move toward or away from the slip ring along the rotor axis to save the radial space of the rotor and improve the space utilization of the electrically excited motor.

[0009] In some scenarios, the rotor shaft is used to house the slip ring and multiple brushes, and at least one brush is located on one side of the slip ring along the rotor axis. The drive mechanism is used to drive the at least one brush to move toward or away from the slip ring along the rotor axis, so as to save the axial and radial space of the rotor and improve the space utilization of the electrically excited motor.

[0010] In one embodiment, the drive mechanism is used to drive multiple brushes to move in the same direction.

[0011] In the electrically excited motor disclosed in this application, multiple brushes are driven to move in the same direction toward or away from the slip ring by a single drive mechanism. The drive mechanism has a simple structure and low cost. Furthermore, a single drive mechanism is easier to control, has low control costs, and facilitates synchronous movement, making it suitable for scenarios where multiple brushes are arranged side-by-side or parallel at intervals.

[0012] In one embodiment, the rotor shaft passes through the central hole of the slip ring. The slip ring includes a positive slip ring and a negative slip ring, which are spaced apart along the axial direction of the rotor. Multiple brushes include positive brushes and negative brushes. Along the radial direction of the rotor, the positive brushes are opposite the positive slip ring. Along the radial direction of the rotor, the negative brushes are opposite the negative slip ring. A drive mechanism is used to drive the positive brushes to move radially toward or away from the positive slip ring and to drive the negative brushes to move radially toward or away from the negative slip ring.

[0013] In the electrically excited motor provided in this application, a drive mechanism drives the positive brush and the negative brush to move radially along the rotor, so that the positive brush moves toward or away from the positive slip ring and the negative brush moves toward or away from the negative slip ring, thereby simplifying the structure of the drive mechanism, reducing costs and saving space, and improving the space utilization of the electrically excited motor.

[0014] In one embodiment, a slip ring passes through a central bore in the rotor shaft. The slip ring includes a positive slip ring and a negative slip ring, with one of the positive and negative slip rings passing through the central bore of the other along the rotor axial direction. A plurality of brushes include positive brushes and negative brushes. Along the rotor axial direction, the positive brushes are opposite the positive slip ring, and along the rotor axial direction, the negative brushes are opposite the negative slip ring. A drive mechanism is used to drive the positive brushes to move along the rotor axial direction toward or away from the positive slip ring and to drive the negative brushes to move along the rotor axial direction toward or away from the negative slip ring.

[0015] In the electrically excited motor provided in this application, the slip ring, drive mechanism, and multiple brushes are located in the central hole of the rotor shaft. The positive and negative brushes are driven to move along the axial direction of the rotor by a drive mechanism, so that the positive brush moves toward or away from the positive slip ring and the negative brush moves toward or away from the negative slip ring, thereby reducing the axial space occupied by the excitation assembly of the electrically excited motor and helping to reduce the axial dimension of the electrically excited motor.

[0016] In one embodiment, the drive mechanism is used to drive multiple brushes to move in different directions from each other.

[0017] In the electrically excited motor provided in this application, multiple brushes are driven by a drive mechanism to move toward or away from the slip ring in different directions. This allows the multiple brushes to move toward or away from the slip ring in their respective directions, providing greater flexibility and making it suitable for scenarios where multiple brushes are vertically, intersecting, circular, or spatially distributed.

[0018] In one embodiment, the drive mechanism connects multiple brushes via a transmission mechanism, which includes multiple first transmission members and at least one second transmission member. Each first transmission member is used to drive a brush. Each second transmission member is used to drive the drive mechanism and at least one second transmission member. Each second transmission member receives the driving force from the drive mechanism and drives the corresponding brush to move through at least one first transmission member.

[0019] In the electrically excited motor provided in this application, the drive mechanism drives multiple brushes to move in different directions through the transmission mechanism, thereby causing the multiple brushes to move toward or away from the slip ring in their respective directions, which is more flexible, reduces the number of drive mechanisms, and lowers the cost.

[0020] In one embodiment, one end of at least one second transmission member is rotatably connected to the same moving member. The other end of each second transmission member is slidably connected to a first transmission member. A drive mechanism is used to drive the moving member to move, the direction of movement of the moving member intersecting the direction of movement of the brush.

[0021] In the electrically excited motor provided in this application, the drive mechanism drives the moving parts to move, and sequentially drives the corresponding brushes to move toward or away from the slip ring through at least one second transmission member and multiple first transmission members.

[0022] In one embodiment, the second transmission member has a ring structure. One end of a plurality of first transmission members is rotatably connected to the same second transmission member, and the other end of each first transmission member is rotatably connected to a brush. A drive mechanism is used to drive the second transmission member to rotate.

[0023] In the electrically excited motor provided in this application, the drive mechanism drives the second transmission component to rotate, and drives the corresponding brushes to move toward or away from the slip ring through multiple first transmission components.

[0024] In one embodiment, the drive mechanism includes a valve spool, a valve body, a reset element, and a coil. The valve body houses a portion of the valve spool, with another portion of the valve spool extending out of the valve body. The coil surrounds a portion of the valve spool. The other portion of the valve spool is used for drive-connection to at least one brush.

[0025] One of the coil and the reset element is used to drive the valve core to move relative to the valve body, thereby causing at least one brush to move toward the slip ring. The other of the coil and the reset element is used to drive the valve core to move in the opposite direction relative to the valve body, thereby causing at least one brush to move away from the slip ring.

[0026] In some scenarios, the coil generates electromagnetic force after being energized. The electromagnetic force overcomes the force of the reset element and drives the valve core to move relative to the valve body, thereby causing at least one brush connected to the valve core to move toward the slip ring until at least one brush connected to the valve core contacts the slip ring. The external excitation current is transmitted to the rotating slip ring through at least one brush connected to the valve core, and then to the rotor winding through the slip ring.

[0027] When the coil is de-energized, the electromagnetic force disappears, and the reset element drives the valve core to move relative to the valve core, thereby causing at least one brush connected to the valve core to move away from the slip ring until at least one brush connected to the valve core separates from the slip ring. At least one brush connected to the valve core and the slip ring no longer contact each other, thereby improving the brush wear caused by long-term contact between the brush and the slip ring and helping to extend the service life of the brush.

[0028] In other scenarios, the coil generates electromagnetic force after being energized. This electromagnetic force overcomes the force of the reset element and drives the valve core to move relative to the valve body. This causes at least one brush connected to the valve core to move away from the slip ring until the at least one brush connected to the valve core separates from the slip ring. This reduces brush wear caused by long-term contact between the brush and the slip ring and helps extend the service life of the brush.

[0029] When the coil is de-energized, the electromagnetic force disappears, and the reset element drives the valve core to move relative to the valve core, thereby moving at least one brush connected to the valve core toward the slip ring until at least one brush connected to the valve core contacts the slip ring. The external excitation current is transmitted to the rotating slip ring through at least one brush connected to the valve core, and then to the rotor winding through the slip ring.

[0030] In one embodiment, the drive mechanism includes a motor, a gear, and a rack. The rack is used to drive at least one brush. The gear meshes with the rack. The motor drives the gear to rotate. The gear drives at least one brush to move toward or away from the slip ring via the rack. The rotation of the motor is converted into linear motion of at least one brush through the meshing of the gear and rack.

[0031] The motor is used to drive the gear to rotate, so as to move at least one brush toward the slip ring through the rack until the brush contacts the slip ring. The external excitation current is transmitted to the rotating slip ring through the brush and then to the rotor winding through the slip ring.

[0032] The motor is used to drive the gear to rotate in the opposite direction, so as to drive at least one brush to move away from the slip ring through the rack until the brush separates from the slip ring and the brush and slip ring no longer contact each other. This improves the brush wear caused by long-term contact between the brush and the slip ring and helps to extend the service life of the brush.

[0033] In one embodiment, the central axis of the gear is parallel or perpendicular to the axial direction of the electrically excited motor.

[0034] In the electrically excited motor provided in this application, the central axis of the gear is parallel to the axial direction of the electrically excited motor, so that the motor and the gear are arranged along the axial direction of the electrically excited motor. This is beneficial to reducing the radial dimension of the electrically excited motor, improving the structural compactness of the electrically excited motor, and increasing the space utilization rate of the electrically excited motor.

[0035] By aligning the central axis of the gear perpendicular to the axial direction of the electrically excited motor, the motor and gear are arranged radially along the motor. This helps reduce the axial dimension of the electrically excited motor and prevents interference between the motor and structures such as the stator and rotor along the axial direction of the motor.

[0036] In some embodiments, the motor and gear are located at one axial end of the electrically excited motor. Utilizing the space at one axial end of the electrically excited motor to arrange the motor and gear is beneficial for controlling the height of the electrically excited motor and improving the space utilization rate of the electrically excited motor.

[0037] In some embodiments, the gear includes a cylindrical gear or a worm gear.

[0038] In one embodiment, one end of the brush extends into the brush holder, and the other end is used to contact the slip ring. The brush holder houses an elastic element, one end of which is connected to the inner wall of the brush holder, and the other end is connected to the brush. The elastic element presses the brush against the slip ring. A drive mechanism is used to move the brush holder toward or away from the slip ring.

[0039] In the electrically excited motor disclosed in this application, the drive mechanism is used to drive the brush holder to move toward or away from the slip ring, thereby causing the brushes to move toward or away from the slip ring. The elastic element inside the brush holder serves two purposes: firstly, it presses the brushes against the slip ring to ensure that the brushes always maintain close contact with the slip ring; secondly, when the brushes move to contact the slip ring under the drive mechanism, the elastic element helps to reduce the impact force of the slip ring on the brushes, which is beneficial to improving the service life of the brushes.

[0040] A second aspect of this application provides a powertrain including a reducer and the aforementioned electrically excited motor, the electrically excited motor being used to drive the reducer.

[0041] An electrically excited motor is used to convert electrical energy into rotational mechanical energy and output torque to a reducer. The reducer is used to reduce the speed, increase the torque, and transmit power to the wheels to drive them to rotate.

[0042] The powertrain provided in this application includes the aforementioned electrically excited motor. Therefore, the powertrain provided in this application solves the same technical problem and has the same technical effect as the electrically excited motor in the above-mentioned technical solution, and will not be repeated here.

[0043] A third aspect of this application provides an electric vehicle including wheels and the aforementioned powertrain for driving the wheels.

[0044] The powertrain is used to drive the wheels to rotate, thereby enabling the electric vehicle to move. The electric vehicle provided in this application includes the aforementioned powertrain. Therefore, the electric vehicle provided in this application solves the same technical problem and has the same technical effect as the powertrain of the above-mentioned technical solutions, and will not be repeated here. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the structure of an electric vehicle provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a powertrain provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of an electrically excited motor provided in an embodiment of this application; Figure 4 A partial structural schematic diagram of an excitation component provided in an embodiment of this application; Figure 5This is one of the structural schematic diagrams of a drive mechanism provided in an embodiment of this application, wherein the coil is not energized; Figure 6 This is one of the structural schematic diagrams of a driving mechanism provided in an embodiment of this application, wherein the coil is energized; Figure 7 This is a second schematic diagram of a drive mechanism provided in an embodiment of this application; Figure 8 This is the third schematic diagram of a drive mechanism provided in the embodiments of this application; Figure 9 This is one of the structural schematic diagrams of an excitation assembly provided in an embodiment of this application, wherein the brush and the slip ring are separated; Figure 10 This is one of the structural schematic diagrams of an excitation assembly provided in an embodiment of this application, wherein the brush is in contact with the slip ring; Figure 11 This is a second schematic diagram of the structure of an excitation assembly provided in an embodiment of this application; Figure 12 This is the third schematic diagram of the structure of an excitation assembly provided in the embodiments of this application; Figure 13 This is the fourth schematic diagram of the structure of an excitation assembly provided in the embodiments of this application; Figure 14 This is the fifth schematic diagram of the structure of an excitation assembly provided in the embodiments of this application; Figure 15 for Figure 14 Schematic diagram of the central collector ring; Figure 16 for Figure 14 A schematic diagram of the structure of the solenoid valve; Figure 17 This is a sixth schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brushes and slip rings are separated; Figure 18 This is a sixth schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brush is in contact with the slip ring; Figure 19 This is the seventh schematic diagram of an excitation assembly provided in an embodiment of the present application, in which the brushes and slip rings are separated; Figure 20 for Figure 19 A partial structural diagram of the intermediate excitation assembly; Figure 21 This is the seventh schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brush is in contact with the slip ring; Figure 22 This is the eighth schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brush and the slip ring are separated; Figure 23 This is the eighth schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brush is in contact with the slip ring; Figure 24 This is the ninth schematic diagram of an excitation assembly provided in an embodiment of this application, wherein the brush and the slip ring are separated; Figure 25 The ninth schematic diagram of an excitation assembly provided in this application embodiment shows that the brush is in contact with the slip ring.

[0046] Figure label: 1000 - Electric vehicles; 100 - Powertrain; 200 - Wheels; 201 - Front wheel; 202 - Rear wheel; 300 - Power battery; 10 - Front drive motor; 101 - Electrically excited motor; 20 - Rear drive motor; 30 - Reducer; 301 - Front drive reducer; 302 - Rear drive reducer; 01-Stator; 02-Rotor; 021-Rotor winding; 03-Rotor shaft; 031-Center hole; 04-Excitation assembly; 1-Collector ring; 11-Positive collector ring; 12-Negative collector ring; 2-Brush; 21-Positive brush; 22-Negative brush; 3-Brush holder; 4-Brush braid; 5-Elastic element; 6-Drive mechanism; 61-Solenoid valve; 611-Valve body; 612-Valve core; 613-Coil; 614-Reset component; 62-Motor; 63-Rack; 631-Annular rack; 64-Gear; 641-Spiral gear; 642-Worm gear; 7-Transmission mechanism; 71-First transmission component; 711-Guide rod; 712-Rudder post; 72-Second transmission component; 721-Push rod; 7211-Through hole; 722-Rudder wheel; 73-Moving component; 74-Guide rail; 75-Connector; 76-Push rod; 77-Spring; 78-Baffle; 79-Guide structure. Detailed Implementation

[0047] In the accompanying drawings of the embodiments of this application, solid structures such as parts and components are represented by guide lines; hollow structures such as openings, holes, spaces, and cavities are represented by guide lines with arrows.

[0048] In electrically excited motors, the rotor is excited by the contact between brushes and slip rings. However, in practical applications, it has been found that the wear of the contact between the brushes and slip rings leads to short brush life and high drag loss, thus limiting the application of electrically excited motors.

[0049] Based on this, this application provides an electrically excited motor to improve the situation where the brushes wear excessively due to long-term contact between the brushes and the slip rings.

[0050] The electrically excited motor provided in this application is used in powertrains and electric vehicles with powertrains, which helps to improve the overall vehicle performance.

[0051] The electric vehicle provided in this application is a wheeled device driven or towed by a power unit. In some embodiments, the electric vehicle includes pure electric vehicles, hybrid electric vehicles, range-extended electric vehicles, or plug-in hybrid electric vehicles, etc.

[0052] Among them, pure electric vehicles are called battery electric vehicles, abbreviated as BEV. Hybrid electric vehicles are called hybrid electric vehicles, abbreviated as HEV. Range-extended electric vehicles are called range-extended electric vehicles, abbreviated as REEV. Plug-in hybrid electric vehicles are called plug-in hybrid electric vehicles. In hybrid electric vehicles, it is abbreviated as PHEV.

[0053] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0054] Figure 1 This is a structural schematic diagram of an electric vehicle provided as an embodiment of this application. (Refer to...) Figure 1 The electric vehicle 1000 includes a powertrain 100 and wheels 200. The powertrain 100 is used to drive the wheels 200 to rotate, thereby enabling the electric vehicle 1000 to move.

[0055] The electric vehicle 1000 also includes a power battery 300. The power battery 300 is used to supply power to the powertrain 100, and is also referred to as a battery pack. The powertrain 100 is used to convert the electrical energy provided by the power battery 300 into mechanical energy to drive the wheels 200 to rotate, thereby enabling the electric vehicle 1000 to move.

[0056] Figure 2 This is a schematic diagram of a powertrain provided in an embodiment of this application. (Refer to...) Figure 2 The part indicated by the dashed box is the powertrain 100, which includes a front drive motor 10 and a rear drive motor 20. The power battery 300 is used to supply power to the front drive motor 10 and the rear drive motor 20.

[0057] The wheel 200 includes two front wheels 201 and two rear wheels 202. The two front wheels 201 refer to the two wheels 200 closest to the front of the vehicle, and the two rear wheels 202 refer to the two wheels 200 closest to the rear of the vehicle. The front drive motor 10 drives the two front wheels 201 through a reducer 30. The rear drive motor 20 drives the two rear wheels 202 through another reducer 30.

[0058] The reducer 30 connected to the front drive motor 10 is called the front drive reducer 301. The reducer 30 connected to the rear drive motor 20 is called the rear drive reducer 302.

[0059] In some embodiments, the front drive motor 10 is the main drive motor of the electric vehicle 1000, and the rear drive motor 20 is the auxiliary drive motor of the electric vehicle 1000.

[0060] In another embodiment, the front drive motor 10 is the auxiliary drive motor of the electric vehicle 1000, and the rear drive motor 20 is the main drive motor of the electric vehicle 1000.

[0061] Because of its high speed, high power, good power factor, lack of magnets, superior overall performance compared to asynchronous motors, lower cost than permanent magnet synchronous motors, efficiency between permanent magnet synchronous motors and asynchronous motors, and the ability to shut off the rotor magnetic field, the electrically excited motor 101 is widely used in vehicle drive scenarios, especially in auxiliary drive scenarios. Therefore, in some embodiments, the front drive motor 10 is an electrically excited motor 101. In some embodiments, the rear drive motor 20 is an electrically excited motor 101. In some embodiments, both the front drive motor 10 and the rear drive motor 20 are electrically excited motors 101.

[0062] The electrically excited motor 101 provided in this application will now be described in further detail with reference to the accompanying drawings.

[0063] Figure 3 This is a schematic diagram of the structure of an electrically excited motor provided in an embodiment of this application. (Refer to...) Figure 3 The electrically excited motor 101 includes a stator 01, a rotor 02, and a rotor shaft 03. The rotor 02 passes through the center hole of the stator 01 along direction A, as shown in the figure. Figure 3 As shown in O1. The rotor shaft 03 passes through the center hole of the rotor 02 along direction A. The center hole of the rotor 02 is as shown in... Figure 3 As shown in O2.

[0064] The rotor 02 includes a rotor winding 021 and a rotor core 022, with the rotor winding 021 mounted on the rotor core 022.

[0065] exist Figure 3In the illustrated embodiment, the electrically excited motor 101 further includes an excitation assembly 04, which includes a slip ring 1 and a plurality of brushes 2. The slip ring 1 is also called a slip ring. The rotor winding 021 of the rotor 02 is connected to the slip ring 1. Each brush 2 is connected to an external excitation power supply. In some embodiments, the external excitation power supply is a DC power supply. Each brush 2 is used to contact the slip ring 1 and provide excitation current to the rotor winding 021 through the slip ring 1.

[0066] The slip ring 1 is fixedly mounted on the rotor shaft 03, therefore, the slip ring 1 is stationary relative to the rotor shaft 03. The slip ring 1 rotates relative to the multiple brushes 2, therefore, the contact between the brushes 2 and the slip ring 1 is a sliding contact. When the electrically excited motor 101 is running, the external excitation current is continuously and smoothly introduced into the rotating rotor winding 021 through the sliding contact between the brushes 2 and the rotating slip ring 1, thereby generating a stable and controllable rotor magnetic field. This magnetic field interacts with the rotating magnetic field generated by the stator 01, ultimately driving the electrically excited motor 101 to rotate and output torque.

[0067] The key function of slip ring 1 and brush 2 is to construct a rotating excitation magnetic field circuit, which is conducive to the conversion of electrical energy into mechanical energy. The performance of slip ring 1 and brush 2 is directly related to the reliability, efficiency and control accuracy of motor excitation.

[0068] In some embodiments, the brush 2 includes a carbon brush, the main components of which are copper and graphite. In other embodiments of this application, the brush 2 is a metal foil or wire bundle of pure copper, silver, gold, or their alloys. Those skilled in the art can selectively design the material of the brush 2 according to actual needs.

[0069] In some embodiments, the collector ring 1 comprises phosphor bronze, tin bronze, or tin-phosphor bronze, with the main component being a copper-tin alloy. In other embodiments of this application, the collector ring 1 is a ring structure of chromium-zirconium copper or silver-copper. Those skilled in the art can selectively design the material of the collector ring 1 according to actual needs.

[0070] Figure 4 This is a partial structural schematic diagram of an excitation assembly provided in an embodiment of this application. (Refer to...) Figure 4 One end of the brush 2 extends into the brush holder 3, and the other end is used to contact the slip ring 1. The end of the brush 2 extending into the brush holder 3 is connected to an external excitation power supply via a brush braid 4. The brush braid 4, also called a brush lead, is a flexible conductive component used to connect the external excitation power supply and the brush 2.

[0071] exist Figure 4 In the given embodiment, the brush holder 3 is used to accommodate the elastic member 5, one end of which is connected to the inner wall of the brush holder 3, and the other end is connected to the brush 2. The elastic member 5 is used to press the brush 2 against the collector ring 1 to ensure that the brush 2 always maintains close contact with the collector ring 1.

[0072] The elastic element 5 refers to a component or assembly that utilizes the elastic deformation of a material to store energy, generate force, or move, and substantially returns to its original shape after the external force is removed. The elastic element 5 can take various forms. In some embodiments, it is a helical spring, a spiral spring, or other types of spring. When the brush 2 is in contact with the slip ring 1, the elastic element 5 is in a compressed state; when the brush 2 separates from the slip ring 1, the elastic element 5 is in a freely extended state. In some embodiments, the elastic element 5 is an elastomer such as rubber or a polymer. Those skilled in the art can selectively design it according to actual needs.

[0073] In the conductive state, the current flows through the contact surface between the brush 2 and the collector ring 1, which is also called the conductive state. A tiny electric arc and high temperature are generated between the brush 2 and the rotating collector ring 1, causing oxygen and water vapor in the air to react with the material of the brush 2, forming a surface film on the contact surface between the brush 2 and the rotating collector ring 1. This surface film includes a graphite crystal transfer layer, metal oxides, adsorbed water vapor and hydrocarbons, etc., thereby playing a lubricating role, reducing the coefficient of friction between the brush 2 and the collector ring 1, and reducing wear.

[0074] In the non-conductive state, the current does not pass through the contact surface between the brush 2 and the collector ring 1. The surface film gradually disappears, and dry friction or boundary friction is formed between the brush 2 and the collector ring 1. As a result, the frictional force between the brush 2 and the collector ring 1 in the non-conductive state is greater than that in the conductive state.

[0075] Therefore, the wear of brush 2 under non-conductive conditions cannot be ignored. Especially in scenarios where the electrically excited motor 101 is in an unloaded state most of the time, the wear of brush 2 is more severe, the life of brush 2 is shortened and the drag loss is high, which limits the application of the electrically excited motor 101. Furthermore, as the speed increases, the wear of brush 2 is aggravated.

[0076] To address the problem of brush 2 wear caused by long-term contact between brush 2 and slip ring 1, in this application, the electrically excited motor 101 includes a drive mechanism 6. The drive mechanism 6 is used to drive at least one brush 2 to move toward slip ring 1 to contact slip ring 1 and to drive at least one brush 2 to move away from slip ring 1 to separate from slip ring 1.

[0077] The brush 2 is moved by the drive mechanism 6 to change its position, thereby enabling the brush 2 and the slip ring 1 to make and separate as needed. When excitation is required, the drive mechanism 6 drives at least one brush 2 to move towards the slip ring 1 until it makes contact with the slip ring 1. The external excitation current is transmitted to the rotor winding 021 through the brush 2 and the rotating slip ring 1 to provide excitation current to the rotor winding 021. When excitation is not required, the drive mechanism 6 drives at least one brush 2 to move away from the slip ring 1 until it separates from the slip ring 1. The brush 2 and the slip ring 1 do not make contact, thereby reducing the brush 2 wear caused by long-term contact between the brush 2 and the slip ring 1 and helping to extend the service life of the brush 2.

[0078] The scenarios requiring excitation include starting, grid connection, operation, and power adjustment of the electrically excited motor 101. Scenarios not requiring excitation include stopping the electrically excited motor 101, abnormal disappearance or severe reduction of the excitation current, testing, or maintenance.

[0079] In this application, there are one or more drive mechanisms 6. When there is only one drive mechanism 6, in some embodiments, the single drive mechanism 6 is used to drive a portion of the multiple brushes 2 in the excitation assembly 04, and in other embodiments, the single drive mechanism 6 is used to drive all the brushes 2 in the excitation assembly 04.

[0080] When there are multiple drive mechanisms 6, each drive mechanism 6 is used to drive at least one brush 2. In some embodiments, the number of brushes 2 driven by the multiple drive mechanisms 6 is the same, and in other embodiments, the number of brushes 2 driven by the multiple drive mechanisms 6 is different.

[0081] In some embodiments, the drive mechanism 6 is used to drive at least one brush 2 to move toward or away from the slip ring 1 along a first direction. The first direction is either the axial or radial direction of the rotor 02.

[0082] In some scenarios, at least one brush 2 is located on one side of the slip ring 1 along the radial direction of the rotor 02. The drive mechanism 6 is used to drive the at least one brush 2 to move toward or away from the slip ring 1 along the radial direction of the rotor 02. The contact area between the brush 2 and the slip ring 1 is large and continuous, preventing the brush 2 from sliding out of the slip ring 1 along the axial direction of the rotor 02, so as to ensure the contact stability between the brush 2 and the slip ring 1 for reliable transmission of excitation current.

[0083] In some scenarios, the slip ring 1 and multiple brushes 2 are located on the outer periphery of the rotor shaft 03, and at least one brush 2 is located on one side of the slip ring 1 along the axial direction of the rotor 02. The drive mechanism 6 is used to drive the at least one brush 2 to move toward or away from the slip ring 1 along the axial direction of the rotor 02, so as to save the radial space of the rotor 02 and improve the space utilization of the electrically excited motor 101.

[0084] In some scenarios, the rotor shaft 03 is used to accommodate the slip ring 1 and multiple brushes 2, and at least one brush 2 is located on one side of the slip ring 1 along the axial direction of the rotor 02. The drive mechanism 6 is used to drive the at least one brush 2 to move toward or away from the slip ring 1 along the axial direction of the rotor 02, so as to save the axial and radial space of the rotor 02 and improve the space utilization of the electrically excited motor 101.

[0085] In scenarios where the drive mechanism 6 is used to drive multiple brushes 2, in some embodiments, the drive mechanism 6 drives multiple brushes 2 to move in the same direction. By using a single drive mechanism 6 to drive multiple brushes 2 to move toward or away from the slip ring 1 in the same direction, the drive mechanism 6 has a simple structure and low cost. Furthermore, a single drive mechanism 6 is easier to control, has low control costs, and facilitates synchronous movement, making it suitable for scenarios where multiple brushes 2 are arranged side-by-side or parallel at intervals.

[0086] In other embodiments, the drive mechanism 6 is used to drive multiple brushes 2 to move in different directions from each other. By using a single drive mechanism 6 to drive multiple brushes 2 to move toward or away from the collector ring 1 in different directions, the multiple brushes 2 can move toward or away from the collector ring 1 in their respective directions, which provides greater flexibility and is suitable for scenarios where multiple brushes 2 are vertically, intersecting, circular, or spatially distributed.

[0087] Below, this application will describe in further detail, with reference to the accompanying drawings, an embodiment in which the drive mechanism 6 drives at least one brush 2 to move toward or away from the slip ring 1.

[0088] Figure 5 and Figure 6 This is one of the structural schematic diagrams of a drive mechanism provided in an embodiment of this application. (Refer to...) Figure 5 and Figure 6 The drive mechanism 6 includes a solenoid valve 61, which includes a valve core 612, a valve body 611, a reset member 614, and a coil 613. The valve body 611 accommodates a portion of the valve core 612, with another portion of the valve core 612 extending out of the valve body 611. The coil 613 surrounds a portion of the valve core 612. One of the coil 613 and the reset member 614 drives the valve core 612 to move relative to the valve body 611 in the X direction. The other of the coil 613 and the reset member 614 drives the valve core 612 to move in the opposite direction relative to the valve body 611 in the X direction.

[0089] Valve core 612 includes three valve core sections, which are respectively as follows: Figure 5The letters b1, b2, and b3 indicate the valve core segment. Coil 613 surrounds the valve core segment indicated by letter b3. The valve core segment indicated by letter b2 is located between the valve core segments indicated by letter b1 and b3. One end of the valve core 612 indicated by letter b1 extends into the valve body 611, and the other end extends out of the valve body 611. A reset member 614 along the X-direction is located on the side of the valve core segment indicated by letter b2 away from the valve core segment indicated by letter b3, with one end connected to the valve core segment indicated by letter b2 and the other end connected to the inner wall of the valve body 611.

[0090] In some embodiments, refer to Figure 6 When coil 613 is energized, it generates an electromagnetic force, which drives valve core 612 to move along the X1 direction, causing valve core 612 to extend relative to valve body 611. (Refer to...) Figure 5 When the coil 613 is de-energized, the electromagnetic force disappears, and the reset component 614 drives the valve core 612 to move along the X2 direction so that the valve core 612 retracts relative to the valve core 612.

[0091] In other embodiments, when the coil 613 is energized, it generates an electromagnetic force that drives the valve core 612 to move along the X2 direction, causing the valve core 612 to retract relative to the valve body 611. When the coil 613 is de-energized, the electromagnetic force disappears, and the reset member 614 drives the valve core 612 to move along the X1 direction, causing the valve core 612 to extend relative to the valve body 611.

[0092] The reset element 614 is used to drive the valve core 612 to extend or retract relative to the valve body 611. The reset element 614 can take various forms; in some embodiments, refer to... Figure 5 and Figure 6 The reset element 614 is a compression spring, with one end connected to the valve core segment indicated by letter b2 and the other end connected to the inner wall of the valve body 611. In other embodiments, the reset element 614 is an elastomer such as rubber or polymer. Those skilled in the art can selectively design it according to actual needs.

[0093] Figure 7 This is a second schematic diagram of a drive mechanism provided in an embodiment of this application. (Refer to...) Figure 7 The drive mechanism 6 includes a motor 62, a gear 64, and a rack 63. The motor 62, as shown... Figure 7 As shown in the dashed box, gear 64 meshes with rack 63. Motor 62 drives gear 64 to rotate in the Y direction. Gear 64 drives rack 63 to move in the Z direction.

[0094] exist Figure 7In the given embodiment, when the motor 62 drives the gear 64 to rotate in the Y1 direction, the rotation of the gear 64 in the Y1 direction causes the rack 63 to move in the Z1 direction. When the motor 62 drives the gear 64 to rotate in the Y2 direction, the rotation of the gear 64 in the Y2 direction causes the rack 63 to move in the Z2 direction.

[0095] Reference Figure 7 Gear 64 is a cylindrical gear 641. The central axis of the cylindrical gear 641 is perpendicular to the length direction of the rack 63, as shown in the figure. Figure 7 As shown in the Z direction. The motor 62 is located on one side of the axial direction of the cylindrical gear 641.

[0096] Figure 8 This is the third schematic diagram of a drive mechanism provided in an embodiment of this application. Figure 7 The illustrated embodiment differs from the one shown in that, Figure 8 In the given embodiment, gear 64 is a worm gear 642. The central axis of the worm gear 642 is parallel to the length direction of the rack 63, and the length direction of the rack 63 is as follows: Figure 8 As shown in the Z direction. Motor 62 is located on one axial side of worm gear 642.

[0097] There are many other forms of drive mechanism 6. In other embodiments of this application, drive mechanism 6 includes linear motor, electric push rod, ball screw, etc. This application does not make a special design for the specific form of drive mechanism 6. Those skilled in the art can selectively design it according to actual needs.

[0098] Below, this application will be described in detail below. Figure 5 to Figure 8 The embodiments of this application will be further described in detail using the drive mechanism 6 shown as an example.

[0099] Figure 9 to Figure 12 Three embodiments of a drive mechanism 6 for driving a brush 2 are shown. Among them, Figure 9 and Figure 10 In the given embodiment, the drive mechanism 6 is Figure 5 and Figure 6 The solenoid valve 61 shown. Figure 11 In the given embodiment, the drive mechanism 6 is Figure 7 The motor 62, rack 63, and cylindrical gear 641 are shown. Figure 12 In the given embodiment, the drive mechanism 6 is Figure 8 The motor 62, rack 63, and worm gear 642 are shown.

[0100] Reference Figure 9 and Figure 10The valve body 611 houses a portion of the valve core 612, with the other portion of the valve core 612 extending out of the valve body 611. A coil 613 surrounds a portion of the valve core 612. The end of the other portion of the valve core 612 is used for a drive connection to a brush 2. By controlling the extension and retraction of the valve core 612 of the solenoid valve 61, the contact or disconnection of the brush 2 with the slip ring 1 is controlled.

[0101] One of the coil 613 and the reset member 614 is used to drive the valve core 612 to move relative to the valve body 611, thereby causing the brush 2 to move toward the slip ring 1. The other of the coil 613 and the reset member 614 is used to drive the valve core 612 to move in the opposite direction relative to the valve body 611, thereby causing the brush 2 to move away from the slip ring 1.

[0102] When coil 613 is energized, it generates an electromagnetic force. When this electromagnetic force is greater than the force exerted by reset member 614, the electromagnetic force drives valve core 612 to extend relative to valve body 611 along a first direction, thereby causing brush 2 to move along the first direction toward slip ring 1 until brush 2 contacts slip ring 1. External excitation current is then transmitted through brush 2 to the rotating slip ring 1, and through slip ring 1 to... Figure 3 The rotor winding 021 in the middle.

[0103] When the coil 613 is de-energized, the electromagnetic force disappears, and the reset member 614 drives the valve core 612 to retract relative to the valve core 612 in the first direction, so as to drive the brush 2 to move away from the collector ring 1 in the first direction until the brush 2 separates from the collector ring 1 and the brush 2 and the collector ring 1 no longer contact each other, so as to improve the wear of the brush 2 caused by long-term contact between the brush 2 and the collector ring 1, and help extend the service life of the brush 2.

[0104] In some embodiments, the valve core 612 is directly connected to the brush 2. In other embodiments, refer to... Figure 9 and Figure 10 The valve core 612 is connected to the brush 2 via the brush holder 3. One end of the brush 2 extends into the brush holder 3, and the other end is used to contact the slip ring 1. The brush holder 3 houses the elastic element 5, one end of which is connected to the inner wall of the brush holder 3, and the other end is connected to the brush 2. The elastic element 5 serves two purposes: firstly, it presses the brush 2 against the slip ring 1 to ensure that the brush 2 always maintains close contact with the slip ring 1; secondly, when the valve core 612 moves the brush 2 to contact the slip ring 1, the elastic element 5 reduces the impact force of the slip ring 1 on the brush 2, which helps to improve the service life of the brush 2.

[0105] pass Figure 9 and Figure 10In this embodiment, when the electrically excited motor 101 is not in operation, the brush 2 is separated from the slip ring 1 and does not contact it. When the electrically excited motor 101 is in operation or when there is a working command, the brush 2 contacts the slip ring 1 to instantaneously conduct the circuit between the brush 2 and the slip ring 1. The response speed is fast, which helps to extend the service life of the brush 2 and reduce the drag torque.

[0106] Figure 9 and Figure 10 In the given embodiment, the coil 613 of the solenoid valve 61 extends when energized and retracts when de-energized, so as to be suitable for scenarios where the electrically excited motor 101 is an auxiliary drive motor or an infrequently used motor.

[0107] In other embodiments of this application, the coil 613 of the solenoid valve 61 is retracted when energized and extended when de-energized, so as to be suitable for scenarios where the electrically excited motor 101 is the main drive motor or a commonly used motor.

[0108] Reference Figure 11 Gear 64 is a cylindrical gear 641, and rack 63 is used to drive the brush 2. Motor 62 drives the cylindrical gear 641 to rotate. The cylindrical gear 641 drives the brush 2 to move toward or away from the slip ring 1 via rack 63. The rotation of motor 62 is converted into linear motion of brush 2 through the meshing transmission of cylindrical gear 641 and rack 63.

[0109] When the motor 62 drives the cylindrical gear 641 to rotate in the Y1 direction, the rotation of the cylindrical gear 641 in the Y1 direction causes the rack 63 to move towards the slip ring 1 in the first direction, which in turn drives the brush 2 to move towards the slip ring 1 until the brush 2 contacts the slip ring 1. The external excitation current is transmitted to the rotating slip ring 1 through the brush 2, and then to the external excitation current through the slip ring 1. Figure 3 The rotor winding 021 in the middle.

[0110] When the motor 62 drives the cylindrical gear 641 to rotate in the Y2 direction, the rotation of the cylindrical gear 641 in the Y2 direction causes the rack 63 to move away from the slip ring 1 in the first direction, which in turn causes the brush 2 to move away from the slip ring 1 until the brush 2 separates from the slip ring 1 and the brush 2 no longer contacts the slip ring 1. This improves the wear of the brush 2 caused by long-term contact between the brush 2 and the slip ring 1 and helps to extend the service life of the brush 2.

[0111] exist Figure 11 In the given embodiment, the central axis of the cylindrical gear 641 is parallel to the axial direction of the slip ring 1. In some scenarios, the axial direction of the slip ring 1 is... Figure 3The axial direction of the electrically excited motor 101 is parallel to the axial direction of the slip ring 1 through the central axis of the cylindrical gear 641, so that the motor 62 and the cylindrical gear 641 are arranged along the axial direction of the electrically excited motor 101. This helps to reduce the radial dimension of the electrically excited motor 101, improve the structural compactness of the electrically excited motor 101, and improve the space utilization of the electrically excited motor 101.

[0112] Reference Figure 12 Gear 64 is a worm gear 642, and rack 63 is used to drive the brush 2. Motor 62 drives the worm gear 642 to rotate. The worm gear 642 drives the brush 2 to move toward or away from the slip ring 1 via rack 63. The rotation of motor 62 is converted into linear motion of brush 2 through the meshing transmission of worm gear 642 and rack 63.

[0113] When the motor 62 drives the worm gear 642 to rotate in the W direction, the rotation of the cylindrical gear 641 causes the rack 63 to move towards the slip ring 1 in the first direction, which in turn drives the brush 2 to move towards the slip ring 1 until the brush 2 contacts the slip ring 1, so as to... Figure 3 The rotor winding 021 increases the excitation current.

[0114] When the motor 62 drives the worm gear 642 to rotate in the opposite direction to the W direction, the rotation of the worm gear 642 causes the rack 63 to move away from the collector ring 1 in the first direction, which in turn causes the brush 2 to move away from the collector ring 1 until the brush 2 separates from the collector ring 1, so as to improve the wear of the brush 2 caused by long-term contact between the brush 2 and the collector ring 1, and help extend the service life of the brush 2.

[0115] To achieve the connection between the worm gear 642 and the rack 63, the tooth profiles of the worm gear 642 and the rack 63 are matched. In some embodiments, the worm gear 642 has a self-locking property, which maintains the position of the rack 63 and the brush 2 after power is cut off. Therefore, when the electrically excited motor 101 is working, it is not necessary to maintain the position of the brush 2 with electricity, effectively improving working efficiency. The meshing of the worm gear 642 and the rack 63 ensures the stability of the relative position between the brush 2 and the slip ring 1.

[0116] exist Figure 12 In the given embodiment, the central axis of the worm gear 642 is perpendicular to the axial direction of the slip ring 1. In some scenarios, the axial direction of the slip ring 1 is the same as the axial direction of the electrically excited motor 101. By making the central axis of the worm gear 642 perpendicular to the axial direction of the slip ring 1, the motor 62 and the worm gear 642 are arranged radially along the electrically excited motor 101. This helps to reduce the axial dimension of the electrically excited motor 101 and prevents the motor 62 from interfering with the stator 01, rotor 02, and other structures along the axial direction of the electrically excited motor 101.

[0117] In some embodiments, the motor 62 and the worm gear 642 are located at one axial end of the electrically excited motor 101. Utilizing the space at one axial end of the electrically excited motor 101 to arrange the motor 62 and the worm gear 642 is beneficial for controlling the height of the electrically excited motor 101 and improving the space utilization rate of the electrically excited motor 101.

[0118] exist Figure 11 and Figure 12 In the given embodiment, since the rotational speed and number of revolutions of the motor 62 are easy to control, the moving position of the brush 2 and the contact speed between the brush 2 and the slip ring 1 are controlled by controlling the motor 62, thereby controlling the impact force when the brush 2 and the slip ring 1 come into contact, thus improving the reliability of the brush 2 and the slip ring 1. Furthermore, after the brush 2 wears out, the motor 62 is controlled to move the brush 2 to a suitable position to ensure stable and reliable contact between the brush 2 and the slip ring 1, ensuring the contact force between the brush 2 and the slip ring 1 throughout its service life.

[0119] Reference Figure 11 and Figure 12 The rack 63 is connected to the brush 2 via the brush holder 3. One end of the brush 2 extends into the brush holder 3, and the other end is used to contact the slip ring 1. The brush holder 3 is used to house the elastic element 5, one end of which is connected to the inner wall of the brush holder 3, and the other end is connected to the brush 2. The elastic element 5 serves two purposes: firstly, it presses the brush 2 against the slip ring 1 to ensure that the brush 2 always maintains close contact with the slip ring 1; secondly, when the valve core 612 moves the brush 2 to contact the slip ring 1, the elastic element 5 reduces the impact force of the slip ring 1 on the brush 2, which helps to improve the service life of the brush 2.

[0120] Figure 13 to Figure 16 Two embodiments are shown, illustrating a drive mechanism 6 for driving multiple brushes 2 to move in the same direction. Among them, Figure 13 In the given embodiment, the slip ring 1, the plurality of brushes 2, and the drive mechanism 6 are located in Figure 3 The outer periphery of the central rotor shaft 03. Figure 14 to Figure 16 In the given embodiment, the slip ring 1, multiple brushes 2 and drive mechanism 6 are located in the center hole 031 of the rotor shaft 03.

[0121] Reference Figure 13 The rotor shaft 03 passes through the center hole of the slip ring 1. The center hole of the slip ring 1 is located in... Figure 13 Not shown in the diagram. Since the rotor shaft 03 passes through the central hole of the slip ring 1, the slip ring 1, the multiple brushes 2, and the drive mechanism 6 are all located on the outer periphery of the rotor shaft 03.

[0122] The collector ring 1 includes a positive collector ring 11 and a negative collector ring 12, which are spaced apart along direction A. Direction A is the axial direction of rotor shaft 03, as well as the axial direction of rotor 02 and collector ring 1.

[0123] In some embodiments, the gap between the positive collector ring 11 and the negative collector ring 12 is filled with insulating material to achieve electrical insulation between the positive collector ring 11 and the negative collector ring 12. Insulating material such as... Figure 13 The letter 'c' in the middle refers to.

[0124] The insulating materials can take many forms. In some embodiments, the insulating materials include insulating adhesives such as epoxy resin, silicone, and polyesterimide resin, as well as insulating sleeves. This application does not limit the structure and material of the insulating materials.

[0125] Multiple brushes 2 include a positive brush 21 and a negative brush 22. Along the first direction, the positive brush 21 is opposite to the positive collector ring 11, and along the first direction, the negative brush 22 is opposite to the negative collector ring 12. The driving mechanism 6 is a solenoid valve 61, the structure of which is similar to... Figure 5 and Figure 6 The structure of the solenoid valve 61 shown is the same, and will not be described again here. The valve core 612 of the solenoid valve 61 is used to connect the positive brush 21 and the negative brush 22 to drive the positive brush 21 to move toward or away from the positive collector ring in a first direction, and to drive the negative brush 22 to move toward or away from the negative collector ring 12 in the first direction.

[0126] The first direction is the radial direction of the rotor shaft 03, as well as the radial direction of the rotor 02 and the radial direction of the slip ring 1.

[0127] exist Figure 13 In the given embodiment, a brush 2 is arranged at each end of the portion of the valve core 612 of the solenoid valve 61 extending out of the valve body 611 along direction A. Specifically, one end of the portion of the valve core 612 of the solenoid valve 61 extending out of the valve body 611 along direction A is used to connect to the positive brush 21, and the other end is used to connect to the negative brush 22, so that the positive brush 21 and the negative brush 22 can be simultaneously driven to move along the first direction through a single solenoid valve 61.

[0128] Furthermore, the valve core 612 is connected to the positive brush 21 via the brush holder 3, and the valve core 612 is connected to the negative brush 22 via the brush holder 3. One end of the positive brush 21 extends into the brush holder 3, and the other end is used to contact the positive collector ring 11. The brush holder 3 of the positive brush 21 is used to house the elastic element 5. One end of the elastic element 5 is connected to the inner wall of the brush holder 3, and the other end is connected to the positive brush 21. The elastic element 5 serves two purposes: firstly, it presses the positive brush 21 against the positive collector ring 11 to ensure that the positive brush 21 always maintains close contact with the positive collector ring 11; secondly, when the valve core 612 moves the positive brush 21 to contact the positive collector ring 11, the elastic element 5 reduces the impact force of the positive collector ring 11 on the positive brush 21, which helps to improve the service life of the positive brush 21.

[0129] The negative brush 22 is set up in the same way as the positive brush 21 in the same way, and will not be described again here.

[0130] In some embodiments, the positive current collector ring 11 is closer to Figure 3 In some embodiments, the negative collector ring 12 is closer to the rotor 02. Figure 3 The rotor 02 in the middle can be selectively designed by those skilled in the art according to actual needs.

[0131] Reference Figure 14 The slip ring 1 passes through the central hole 031 of the rotor shaft 03, and the slip ring 1, multiple brushes 2, and drive mechanism 6 are all located in the central hole 031 of the rotor shaft 03. This reduces the axial space occupied by the excitation assembly 04 on the electrically excited motor 101, which is beneficial for reducing the axial dimension of the electrically excited motor 101. The drive mechanism 6 is a solenoid valve 61, and the structure of the solenoid valve 61 is similar to... Figure 5 and Figure 6 The structure of the solenoid valve 61 shown is the same, so it will not be described again here.

[0132] The winding leads of rotor winding 021, the control wires of solenoid valve 61, and the wiring of brush 2 all extend from the center hole 031 of rotor shaft 03. The winding leads of rotor winding 021 are as follows: Figure 14 The letter e1 indicates the control wire of solenoid valve 61, as shown below. Figure 14 The letter e2 refers to the connection of brush 2, which is also the connection of brush braid 4. Figure 14 The letter e3 in the middle refers to.

[0133] Reference Figure 15 The collector ring 1 includes a positive collector ring 11 and a negative collector ring 12. The negative collector ring 12 passes through the central hole of the positive collector ring 11 along a first direction, and the positive collector ring 11 and the negative collector ring 12 are spaced apart. The first direction is the axial direction of the rotor shaft 03, and also the axial direction of the rotor 02 and the axial direction of the collector ring 1.

[0134] In some embodiments, the gaps between the positive collector ring 11 and the negative collector ring 12, and the gap between the positive collector ring 11 and the inner wall of the rotor shaft 03, are respectively filled with insulating material to achieve electrical insulation between the positive collector ring 11 and the negative collector ring 12, and electrical insulation between the positive collector ring 11 and the rotor shaft 03. The insulating material between the positive collector ring 11 and the inner wall of the rotor shaft 03 is as follows: Figure 14 The insulating material between the positive collector ring 11 and the negative collector ring 12, as indicated by the letter d1, is as follows: Figure 15 The letter d2 in the middle refers to.

[0135] In some embodiments, the insulating material referred to by the letter d1 is the same as the insulating material referred to by the letter d2; in other embodiments, the insulating material referred to by the letter d1 is different from the insulating material referred to by the letter d2. The insulating material can take many forms. In some embodiments, the insulating material includes insulating adhesives such as epoxy resin, silicone, and polyesterimide resin, as well as insulating sleeves. This application does not limit the structure and material of the insulating material.

[0136] Reference Figure 14 and Figure 16 The plurality of brushes 2 include a positive brush 21 and a negative brush 22, with one negative brush 22. Along a first direction, the positive brush 21 is opposite to the positive collector ring 11, and along the first direction, the negative brush 22 is opposite to the negative collector ring 12. The end of the valve core 612 of the solenoid valve 61 extending out of the valve body 611 along the first direction is used to fix the positive brush 21 and the negative brush 22, so that the positive brush 21 and the negative brush 22 can be simultaneously driven to move along the first direction by a single solenoid valve 61.

[0137] Valve core 612 is connected to positive brush 21 via brush holder 3, and valve core 612 is connected to negative brush 22 via brush holder 3. The arrangement of positive brush 21 and negative brush 22 within brush holder 3 is as follows: Figure 13 The embodiments shown are the same, and will not be described again here.

[0138] exist Figure 14 to Figure 16 In the given embodiment, there are two positive brushes 21, and a negative brush 22 is located between the two positive brushes 21. The two positive brushes 21 and the negative brush 22 are arranged side by side along the radial direction of the slip ring 1. The multiple brushes 2 and the solenoid valve 61 do not contact the rotor shaft 03, but are fixed to a structure such as the motor end cover outside the rotor shaft 03, which is fixed relative to the stator 01 of the electrically excited motor 101.

[0139] exist Figure 14 The given embodiments show two positive brushes 21 and one negative brush 22. In some embodiments of this application, there is only one positive brush 21 and one negative brush 22. In other embodiments, there are multiple positive brushes 21 and multiple negative brushes 22. In still other embodiments, there is only one positive brush 21 and multiple negative brushes 22. Those skilled in the art can selectively design according to actual needs.

[0140] In this design, the sum of the cross-sectional areas of all the positive brushes 21 on the valve core 612 of the solenoid valve 61 is the same as the sum of the cross-sectional areas of all the negative brushes 22, so that the current density flowing through the positive brushes 21 and the negative brushes 22 is the same, ensuring that the current density and wear rate of the positive brushes 21 and the negative brushes 22 are balanced, thereby maintaining the stable operation of the motor 62 and extending the overall service life of the positive brushes 21 and the negative brushes 22.

[0141] In other embodiments of this application, the positive current collector ring 11 passes through the central hole of the negative current collector ring 12, and the other structural arrangements are the same as those in the previous embodiment. Figure 14 The same principles are used to meet the needs of different scenarios.

[0142] Figure 17 to Figure 25 Four embodiments are shown in which a drive mechanism 6 drives multiple brushes 2 to move in different directions relative to each other via a transmission mechanism 7. The drive mechanism 6 drives the multiple brushes 2 to move in different directions relative to each other via the transmission mechanism 7, thereby causing the multiple brushes 2 to move toward or away from the slip ring 1 in their respective directions. This provides greater flexibility, reduces the number of drive mechanisms 6, and lowers costs.

[0143] Figure 17 and Figure 18 In the given embodiment, the driving mechanism 6 is a solenoid valve 61, which drives two brushes 2 to move in different directions through a transmission mechanism 7. Figure 19 to Figure 21 In the given embodiment, the drive mechanism 6 is a solenoid valve 61, which is used to drive three brushes 2 to move in different directions from each other through a transmission mechanism 7. Figure 22 to Figure 23 In the given embodiment, the drive mechanism 6 consists of a motor 62, a worm gear 642, and a ring rack 631, and the solenoid valve 61 is used to drive the three brushes 2 to move in different directions through a transmission mechanism 7.

[0144] Reference Figure 17 and Figure 18 The drive mechanism 6 is connected to multiple brushes 2 via a transmission mechanism 7. The drive mechanism 6 is a solenoid valve 61, and the structure of the solenoid valve 61 is similar to... Figure 5 The structure of the solenoid valve 61 is the same, so it will not be described again here.

[0145] The transmission mechanism 7 includes a plurality of first transmission members 71 and at least one second transmission member 72. Each first transmission member 71 is used to drive a brush 2, and the second transmission member 72 is used to drive at least one first transmission member 71 and the drive mechanism 6. Each second transmission member 72 is used to receive the driving force of the drive mechanism 6 and drive the corresponding brush 2 to move through at least one first transmission member 71.

[0146] Figure 17 and Figure 18In the given embodiment, the number of first transmission members 71 and second transmission members 72 is the same, both being two. Each second transmission member 72 is used to receive the driving force of the drive mechanism 6 and drive a corresponding brush 2 to move toward or away from the slip ring 1 through a first transmission member 71. A solenoid valve 61 is used to control the movement of the two brushes 2 at different angles, thereby reducing the use of the solenoid valve 61 and lowering costs.

[0147] Both first transmission components 71 are guide rods 711, each guide rod 711 being used to connect to one brush 2. Both second transmission components 72 are push rods 721, one end of each push rod 721 being rotatably connected to a moving component 73, and the other end being slidably connected to a guide rod 711. Movement of the push rod 721 drives the guide rod 711 to move along a first direction, thereby driving the brush 2 to move along the first direction.

[0148] The guide rod 711 is mounted on the guide rail 74, which guides the guide rod 711 to move along a first direction. The push rod 721 includes a through hole 7211, through which a connector 75 passes to fix the guide rod 711. The through hole 7211 is an elongated through hole 7211 to facilitate the movement of the connector 75 within the through hole 7211, thereby driving the guide rod 711 to move along the first direction, and consequently driving the brush 2 to move along the first direction.

[0149] The valve stem of the solenoid valve 61 is connected to a movable member 73, which drives the movable member 73 to move along a second direction. This second direction intersects the first direction. (See reference...) Figure 18 When the coil 613 is energized, it generates an electromagnetic force, which drives the valve core 612 to move along the e1 direction, thereby causing the moving part 73 to move along the e1 direction. Since the push rod 721 is rotatably connected to the moving part 73, the movement of the moving part 73 along the e1 direction reduces the angle between the push rod 721 and the valve core 612, and drives the guide rod 711 to move along the first direction toward the slip ring 1, until the brush 2 connected to the guide rod 711 contacts the slip ring 1.

[0150] Reference Figure 17 When coil 613 is de-energized, the electromagnetic force disappears, and reset component 614 drives valve core 612 to move along direction e2, which in turn drives moving component 73 to move along direction e2. Since push rod 721 is rotatably connected to moving component 73, the movement of moving component 73 along direction e2 increases the angle between push rod 721 and valve core 612, and through push rod 721 drives guide rod 711 to move away from slip ring 1 along the first direction until brush 2 connected to guide rod 711 separates from slip ring 1.

[0151] Each first transmission component 71 is connected to the brush 2 via a brush box 3. The brush box 3 serves to install and guide the movement of the brush 2. The arrangement of the brush 2 within the brush box 3 is similar to... Figure 4The embodiments shown are the same, and will not be described again here.

[0152] Reference Figure 19 to Figure 21 The drive mechanism 6 is connected to multiple brushes 2 via a transmission mechanism 7. The drive mechanism 6 is a solenoid valve 61, and the structure of the solenoid valve 61 is similar to... Figure 5 The structure of the solenoid valve 61 is the same, so it will not be described again here.

[0153] Reference Figure 20 Multiple brushes 2 surround the collector ring 1 circumferentially, and are spaced apart circumferentially. Each brush 2 is installed inside a brush holder 3, and the arrangement of the brushes 2 inside the brush holder 3 is the same as... Figure 4 The embodiments shown are the same, and will not be described again here.

[0154] The transmission mechanism 7 includes multiple first transmission components 71 and one second transmission component 72. The second transmission component 72 has a ring structure. One end of each of the multiple first transmission components 71 is rotatably connected to the same second transmission component 72, and the other end of each first transmission component 71 is rotatably connected to a brush 2. A solenoid valve 61 is used to drive the second transmission component 72 to rotate.

[0155] The first transmission component 71 is a rudder stick 712, and the second transmission component 72 is a rudder wheel 722. One end of each rudder stick 712 is rotatably connected to the rudder wheel 722, and the other end is rotatably connected to a brush 2. The solenoid valve 61 drives the rudder wheel 722 to rotate. The rotation of the rudder wheel 722 causes a change in the position of one end of the rudder stick 712, which in turn causes the other end of the rudder stick 712 to move the corresponding brush 2 toward or away from the solenoid valve 61. The solenoid valve 61 controls the mechanical structures such as the rudder wheel 722 and the rudder stick 712. A push rod 76 drives the rudder wheel 722 to rotate, which in turn drives the rudder stick 712 to move the brush 2, achieving controllable adjustment of the brush 2's position, and thus controllable contact and disconnection between the brush 2 and the slip ring 1.

[0156] exist Figure 19 and Figure 21 In the given embodiment, the rudder 712 is used to directly connect to the brush 2, and each brush 2 is installed in the brush holder 3. The brush holder 3 serves to install and guide the movement of the brush 2. In other embodiments, the movement and guidance of the brush 2 are achieved in other ways, and this application does not impose any special limitations on this.

[0157] There are various ways to connect the rudder stick 712 and the brush 2. In some embodiments, a cylindrical shaft is fixed on the brush 2, and the rudder stick 712 has a circular hole. The cylindrical shaft passes through the circular hole and is connected to the brush 2 to realize the push-pull movement of the brush 2. The cylindrical shaft is a metal shaft with high wear resistance.

[0158] There are several ways to fix the metal shaft and the brush 2. In some embodiments, the metal shaft is placed in the brush 2 mold before the brush 2 is sintered. In other embodiments, holes are pre-drilled in the brush 2 mold, and the metal shaft is inserted after the brush 2 is sintered. Besides these two methods, the brush 2 and the metal shaft can also be fixed together in other ways.

[0159] In other embodiments of this application, the rudder stick 712 is connected to the brush 2 via the brush box 3, and those skilled in the art can selectively design it according to actual needs.

[0160] exist Figure 19 and Figure 21 In the given embodiment, the steering wheel 722 is connected to the push rod 76, and the solenoid valve 61 drives the push rod 76 to rotate, thereby causing the steering wheel 722 to rotate, which in turn drives the corresponding brush 2 to move toward or away from the solenoid valve 61 via the steering rod 712. The drive mechanism 6 also includes a baffle 78 and a spring 77, with one end of the spring 77 connected to the baffle 78 and the other end connected to the push rod 76. The spring 77 is used to reset the push plate.

[0161] When controlled by motor 62, the rotation of steering wheel 722 is controlled by worm gear 642 and ring rack 631 or gear 64 on steering wheel 722, which also achieves self-locking of brush 2 position. This allows brush 2 to be fixed in a certain position even without power.

[0162] Reference Figure 21 When the coil 613 is energized, it generates an electromagnetic force, which drives the valve core 612 to move in the direction of f1. The valve core 612 abuts against the push rod 76 and presses one end of the push rod 76 against the spring 77 in the direction of f1. The spring 77 is compressed, and the other end of the push rod 76 drives the rudder wheel 722 to rotate in the direction of g1, so that the end of the rudder rod 712 connected to the rudder wheel 722 also rotates in the direction of g1. The end of the rudder rod 712 away from the rudder wheel 722 drives the corresponding brush 2 to move toward the collector ring 1 until the brush 2 connected to the rudder rod 712 contacts the collector ring 1.

[0163] Reference Figure 19 When coil 613 is de-energized, the electromagnetic force disappears, and reset component 614 drives valve core 612 to move along direction f2 until valve core 612 separates from push rod 76. The elastic force of spring 77 causes one end of push component to move along direction f2, spring 77 extends, and the other end of push rod 76 drives steering wheel 722 to rotate along direction g2, so that the end of rudder rod 712 connected to steering wheel 722 also rotates along direction g2. The end of rudder rod 712 away from steering wheel 722 drives the corresponding brush 2 to move away from slip ring 1 until brush 2 connected to rudder rod 712 separates from slip ring 1.

[0164] and Figure 19 to Figure 21The difference between the given embodiments is that, Figure 22 and Figure 23 In the given embodiment, the drive mechanism 6 is connected to multiple brushes 2 via a transmission mechanism 7. The drive mechanism 6 consists of a motor 62, a worm gear 642, and a ring rack 631, which surrounds and is connected to the outer periphery of the steering wheel 722.

[0165] The worm gear 642 rotates by driving the steering wheel 722 to rotate in both forward and reverse directions. (See reference...) Figure 23 The motor 62 drives the worm gear 642 to rotate in the forward direction, and through the meshing of the worm gear 642 and the ring rack 631, it drives the rudder wheel 722 to rotate in the g1 direction, which in turn drives the rudder stick 712 to rotate at one end connected to the rudder wheel 722 in the g1 direction. The end of the rudder stick 712 away from the rudder wheel 722 drives the corresponding brush 2 to move toward the collector ring 1 until the brush 2 connected to the rudder stick 712 contacts the collector ring 1.

[0166] Reference Figure 22 The motor 62 drives the worm gear 642 to rotate in the opposite direction, and through the meshing of the worm gear 642 and the ring rack 631, it drives the rudder wheel 722 to rotate in the g2 direction, which in turn drives the rudder stick 712 to rotate at one end connected to the rudder wheel 722 in the g2 direction. The end of the rudder stick 712 away from the rudder wheel 722 drives the corresponding brush 2 to move away from the collector ring 1 until the brush 2 connected to the rudder stick 712 separates from the collector ring 1.

[0167] In order to connect the worm gear 642 and the annular rack 631, the tooth profiles of the worm gear 642 and the annular rack 631 are matched. In some embodiments, the annular rack 631 can be replaced with a gear 64 that meshes with the worm gear 642.

[0168] Because the worm gear 642 has a self-locking property, the position of the rack 63 and brush 2 is maintained by the self-locking of the worm gear 642 after power is cut off. Therefore, it is not necessary to maintain the position of the brush 2 by electricity when the electrically excited motor 101 is working, which effectively improves working efficiency. The meshing of the worm gear 642 and the rack 63 ensures the stability of the relative position between the brush 2 and the slip ring 1. Furthermore, since the speed and number of revolutions of the motor 62 are controllable, it is beneficial to accurately control the position of the brush 2 and the contact speed or contact impact force between the brush 2 and the slip ring 1. When the brush 2 wears a lot, the elongation of the brush 2 can be controlled by controlling the motor 62 to ensure the contact force of the brush 2 throughout its entire life cycle.

[0169] Based on this, Figure 22 and Figure 23 In this embodiment, the rudder 712 is directly connected to the brush 2. In some embodiments, each brush 2 is installed in the brush box 3. The brush box 3 serves to install and limit the movement of the brush 2. In this embodiment, the elastic element 5 in the brush box 3 can be omitted, so that the movement of the brush 2 relative to the slip ring 1 is controlled by the motor 62.

[0170] and Figure 22 and Figure 23 The difference between the given embodiments is that, Figure 24 and Figure 25 In the given embodiment, the end of the rudder stick 712 that is away from the rudder wheel 722 is connected to the brush 2 via the brush box 3.

[0171] To achieve the movement of the brush box 3, each brush box 3 corresponds to a guide structure 79. The brush box 3 moves relative to the guide structure 79 towards or away from the slip ring 1 via the cooperation of the steering wheel 722 and the rudder stick 712, thereby driving the movement of the brush 2. The end of the rudder stick 712 away from the steering wheel 722 drives the corresponding brush 2 towards the slip ring 1 until the brush 2 connected to the rudder stick 712 contacts the slip ring 1. The end of the rudder stick 712 away from the steering wheel 722 drives the corresponding brush 2 away from the slip ring 1 until the brush 2 connected to the rudder stick 712 separates from the slip ring 1.

[0172] exist Figure 22 and Figure 23 In the given embodiment, an elastic element connects the brush holder 3 and the brush 2. This elastic element controls the contact force between the brush 2 and the slip ring 1 and adaptively adjusts the length of the brush 2. This solves the problem that some brushes 2 may not contact the slip ring 1 under the same movement due to uneven wear after long-term use. Furthermore, the rudder rod 712 connects to the brush holder 3, allowing the use of common brushes 2, which is more cost-effective and easier to manufacture.

[0173] Reference Figure 19 to Figure 25 The illustration shows an embodiment of a drive mechanism 6 used to drive a single ring of brushes 2. In other embodiments of this application, multiple brushes 2 may surround a collector ring 1 to form two or more rings of brushes 2, the two or more rings of brushes 2 being spaced apart axially along the collector ring 1, and each ring of brushes 2 being spaced apart circumferentially along the collector ring 1, so that the two or more rings of brushes 2 are simultaneously driven by a single drive mechanism 7. In some embodiments, multiple positive brushes 21 surround the collector ring 1 to form one ring of brushes 2, and multiple negative brushes 22 surround the collector ring 1 to form another ring of brushes 2. The one ring of brushes 2 and the other ring of brushes 2 are spaced apart axially along the collector ring 1, and the two rings of brushes 2 are simultaneously driven by a single drive mechanism 7.

[0174] Based on the above, the electrically excited motor 101 provided in this application achieves on-demand switching of the excitation component 04 by moving the brush 2 relative to the slip ring 1, so that in the non-working state, the brush 2 is separated from the slip ring 1 and does not make contact. When excitation is required or there is a working command, the brush 2 is brought into contact and conducts instantaneously. Using the electrically excited motor 101 of this application, the on-demand switching of the excitation component 04 is realized, and the brush 2 responds quickly, solving the problem of wear and lifespan caused by long-term contact between the brush 2 and the slip ring 1. This gives the electrically excited motor 101 the characteristics of long lifespan and low drag of an induction excitation system.

[0175] In some embodiments, the position of the brush 2 is controllable, and the elastic element 5 located in the brush box 3 can be saved, so as to control the contact pressure between the brush 2 and the slip ring 1 by feedback on the conductivity of the rotor 02.

[0176] The embodiments of this application solve the problems of lifespan and mechanical wear during non-operating states of the contact excitation assembly 04. When the contact excitation assembly 04 is applied to the auxiliary drive system of pure electric or hybrid vehicles, it significantly reduces the drag loss of the electrically excited motor 101, improving the overall vehicle range. Furthermore, compared to the non-contact excitation assembly 04, the response time of this application is faster, especially in power-off conditions. For auxiliary drive applications, since the brush 2 does not contact the slip ring 1 most of the time, it is beneficial to multiply the lifespan of the brush 2. In some embodiments, the front auxiliary drive system of current four-wheel drive vehicles operates for only 5-7% of its entire lifespan. This means that the lifespan of the brush 2 is increased by 15-20 times. Considering that the brush 2 wears more severely under non-conductive conditions, the lifespan increase is even greater.

[0177] In some embodiments, by arranging the excitation assembly 04 within the shaft, the problem of excessive axial length and difficulty in arrangement caused by the excitation assembly 04 in the electrically excited motor 101 is solved, thus expanding the application scenarios of the electrically excited motor 101. This is especially true in hybrid or dual-motor applications where high axial length requirements for the motor are necessary.

[0178] Furthermore, the cost is controllable, and the overall structure requires fewer additional parts. Only one actuator is needed to control the movement of multiple brushes 2 of the positive and negative collector rings, avoiding current fluctuations caused by asynchronous movement and lifespan issues caused by excessive current through the brushes 2.

[0179] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An electrically excited motor, characterized in that, The rotor shaft of the electrically excited magneto passes through the central hole of the rotor of the electrically excited magneto, and the rotor winding of the rotor is connected to the slip ring of the electrically excited magneto. The electrically excited magneto includes: Multiple brushes, each of the brushes being used to contact the slip ring and provide excitation current to the rotor winding through the slip ring; A driving mechanism for driving at least one of the brushes toward the slip ring to contact the slip ring and for driving at least one of the brushes away from the slip ring to separate from the slip ring.

2. The electrically excited motor according to claim 1, characterized in that, The drive mechanism is used to drive at least one of the brushes to move toward or away from the slip ring along a first direction, the first direction being the axial or radial direction of the rotor.

3. The electrically excited motor according to claim 1 or 2, characterized in that, The drive mechanism is used to drive the multiple brushes to move in the same direction.

4. The electrically excited motor according to claim 3, characterized in that, The rotor shaft passes through the central hole of the slip ring, which includes a positive slip ring and a negative slip ring, and the positive slip ring and the negative slip ring are distributed at intervals along the axial direction of the rotor. The plurality of brushes include a positive brush and a negative brush. The positive brush is opposite to the positive collector ring along the radial direction of the rotor, and the negative brush is opposite to the negative collector ring along the radial direction of the rotor. The driving mechanism is used to drive the positive brush to move toward or away from the positive collector ring along the radial direction of the rotor and to drive the negative brush to move toward or away from the negative collector ring along the radial direction of the rotor.

5. The electrically excited motor according to claim 3, characterized in that, The collector ring passes through the central hole of the rotor shaft. The collector ring includes a positive collector ring and a negative collector ring. Along the axial direction of the rotor, one of the positive collector ring and the negative collector ring passes through the central hole of the other. The plurality of brushes include a positive brush and a negative brush. Along the axial direction of the rotor, the positive brush is opposite to the positive collector ring, and along the axial direction of the rotor, the negative brush is opposite to the negative collector ring. The driving mechanism is used to drive the positive brush to move toward or away from the positive collector ring along the axial direction of the rotor and to drive the negative brush to move toward or away from the negative collector ring along the axial direction of the rotor.

6. The electrically excited motor according to claim 1 or 2, characterized in that, The drive mechanism is used to drive the multiple brushes to move in different directions from each other.

7. The electrically excited motor according to claim 6, characterized in that, The drive mechanism connects to multiple brushes via a transmission mechanism. The transmission mechanism includes multiple first transmission members and at least one second transmission member. Each first transmission member is used to drive one brush, and each second transmission member is used to drive the drive mechanism and at least one second transmission member. Each of the second transmission elements is used to receive the driving force of the drive mechanism and drive the corresponding brush to move through at least one of the first transmission elements.

8. The electrically excited motor according to claim 7, characterized in that, One end of the at least one second transmission member is used to rotatably connect to the same moving member, and the other end of each second transmission member is used to slidably connect to one of the first transmission members; The driving mechanism is used to drive the moving component to move, and the moving direction of the moving component intersects with the moving direction of the brush.

9. The electrically excited motor according to claim 7, characterized in that, The second transmission component is a ring structure. One end of each of the plurality of first transmission components is rotatably connected to the same second transmission component, and the other end of each of the first transmission components is rotatably connected to a brush. The driving mechanism is used to drive the second transmission component to rotate.

10. The electrically excited motor according to any one of claims 1-9, characterized in that, The drive mechanism includes a valve core, a valve body, a reset element, and a coil. The valve body is used to house a portion of the valve core, and another portion of the valve core extends out of the valve body. The coil surrounds a portion of the valve core, and the other portion of the valve core is used for drive connection to at least one of the brushes. One of the coil and the reset member is used to drive the valve core to move relative to the valve body, so as to drive at least one of the brushes to move toward the slip ring; the other of the coil and the reset member is used to drive the valve core to move in the opposite direction relative to the valve body, so as to drive at least one of the brushes to move away from the slip ring.

11. The electrically excited motor according to any one of claims 1-9, characterized in that, The drive mechanism includes a motor, a gear, and a rack. The rack is used to drive at least one of the brushes. The gear is used to mesh with the rack. The motor is used to drive the gear to rotate. The gear is used to drive at least one of the brushes to move toward or away from the slip ring via the rack.

12. The electrically excited motor according to claim 11, characterized in that, The central axis of the gear is parallel or perpendicular to the axis of the electrically excited motor.

13. The electrically excited motor according to any one of claims 1-12, characterized in that, One end of the brush extends into the brush holder, and the other end is used to contact the slip ring. The brush holder is used to accommodate an elastic element. One end of the elastic element is connected to the inner wall of the brush holder, and the other end is connected to the brush. The elastic element is used to press the brush against the slip ring. The drive mechanism is used to move toward or away from the slip ring through the brush holder.

14. A powertrain, characterized in that, The powertrain includes a reducer and an electrically excited motor according to any one of claims 1-13, the electrically excited motor being used for drive connection to the reducer.

15. An electric vehicle, characterized in that, The electric vehicle includes wheels and the powertrain of claim 14, the powertrain being used to drive the wheels.

Images