Vibration isolation device for drive electric motor, and control strategy

Abstract

Provided in the present invention are a vibration isolation device for a drive electric motor, and a control strategy. The vibration isolation device for a drive electric motor comprises an upper liquid chamber and a lower liquid chamber arranged on a vehicle body and located below the drive electric motor, wherein a support partition is provided between the upper liquid chamber and the lower liquid chamber to separate one from the other. The vibration isolation device is characterized in that the support partition is provided with at least one regulating valve communicating the upper liquid chamber and the lower liquid chamber; the regulating valve comprises at least two channels having different cross-sectional areas, and the valve of the regulating valve is driven by a valve driving mechanism to switch the regulating valve to different channels; the valve driving mechanism and the drive electric motor are both electrically connected to a controller. The present invention effectively solves the problem of low-frequency vibration isolation in a drive electric motor mounting system, and meets the requirements for both support and vibration amplitude suppression under high-torque conditions of the electric motor, thereby meeting the vibration isolation performance requirements of the electric motor under various operating conditions, while providing reliability that is significantly superior to that of current rubber mounts.

Description

A vibration isolation device and control strategy for a drive motor Technical Field

[0001] This invention belongs to the field of new energy vehicles, specifically relating to a vibration isolation device and control strategy for a drive motor. Background Technology

[0002] The vibration isolation structure of the drive motor is an important component of the power system of new energy buses. Currently, most existing new energy bus drive motors use cylindrical or square rubber vibration isolation devices, and their vibration isolation concept follows the vibration isolation design structure of traditional diesel engines. The rubber vibration isolation pads also basically adopt the vibration isolation structure and stiffness of traditional power vehicles. However, this rubber vibration isolation structure has the following disadvantages for pure electric drive systems:

[0003] 1. Low-frequency excitation vibrations of the motor rotor and drive shaft cannot be isolated, causing the rotational vibrations of the motor and drive shaft to be transmitted to the vehicle body, affecting the ride comfort. The drive motor itself is lightweight; compared to a diesel powertrain weighing 1-1.5 tons, the drive motor weighs only 100-400 kg. This results in a very high natural modal frequency for the drive motor system. The natural frequency is the system's resonant frequency. When the external excitation frequency approaches or reaches the system's natural frequency, the system vibration reaches its maximum, also known as resonance. As the excitation frequency continues to increase, the system vibration at the natural frequency will continue to decrease until the excitation frequency is greater than 2^0.5 times the natural frequency, at which point the amplitude of the excitation vibration will decay, and the decay amplitude will be even greater as the excitation frequency continues to increase. The same rubber vibration isolation element is used for the powertrain of a diesel engine, whose natural modal frequency is basically within 13Hz. Thus, excitation above 18Hz can be attenuated by the rubber vibration isolation pad. However, the natural modal frequency of the drive motor can reach 30Hz, so excitation above 42Hz can be reduced. The rotational excitation frequency of the motor and drive shaft is between 25Hz and 55Hz. This means that the rotational imbalance excitation between the motor rotor and the drive shaft cannot be isolated by the rubber pad, causing vibration problems during high-speed driving of the whole vehicle.

[0004] 2. Suspension pads are prone to tearing, resulting in poor reliability: The maximum torque of the main engine in a traditional powertrain is 1600 N·mm, while the maximum peak torque of the drive motor matched with similar bus products reaches 3000 N·mm. Under high torque, the same rubber vibration damping pads are easily torn. Rubber can withstand pressure but is poor at tensile strength. Under high torque, the drive motor will inevitably be subjected to pressure on one side and tension on the other, making the rubber on the side under tension extremely prone to tearing. This results in significantly lower reliability compared to traditional vehicles.

[0005] 3. The stiffness of rubber mounts is generally too high, which cannot significantly reduce the stiffness to meet the vibration isolation requirements of drive motors: Due to the easy aging and tearing of rubber mounts, the stiffness of rubber mounts cannot be made very low in the development structure. At present, the stiffness of rubber mounts in drive motors of new energy buses and commercial vehicles is basically in the range of 1000N / m-2000N / mm, which cannot be 300N / mm or below. For drive motors, in order to reduce the natural modal frequency to within 13Hz, the stiffness of rubber mounts must be <300N / mm, which is obviously impossible. That is to say, the current stiffness limit of rubber mounts can no longer meet the vibration isolation requirements of drive motors.

[0006] 4. Rubber suspension mounts offer limited stiffness and damping, failing to provide adequate stiffness support under diverse operating conditions. During full-throttle acceleration, the high torque necessitates high stiffness and damping from the suspension mounts to limit torsional displacement and vibration amplitude. Conversely, when the drive motor operates at low torque (constant speed or coasting), lower stiffness and damping are required to maximize vibration isolation. Current suspension mounts cannot meet these requirements.

[0007] Patent CN108488306A discloses an adaptive multi-inertia channel hydraulic suspension and its adaptive method. However, this structure is applied below the engine and can only passively adapt to the environment, responding to changes in external pressure; it cannot actively reduce vibration or reduce the amplitude of vibration. Summary of the Invention

[0008] This invention provides a vibration isolation device and control strategy for a drive motor.

[0009] The objective of this invention is achieved in the following manner: a drive motor vibration isolation device includes an upper liquid chamber and a lower liquid chamber disposed on the vehicle body and located below the drive motor, with a supporting partition separating the upper and lower liquid chambers; at least one regulating valve connecting the upper and lower liquid chambers is disposed on the supporting partition; the regulating valve includes at least two channels with different cross-sectional areas, and the valve of the regulating valve is driven by a valve driving mechanism to switch the regulating valve to different channels; the valve driving mechanism and the drive motor are both electrically connected to a controller.

[0010] The supporting partition is provided with through holes, and at least one of the through holes is fixedly installed with a regulating valve. The regulating valve includes an inlet channel connecting the upper liquid chamber and at least two outlet channels with different cross-sectional areas connecting the lower liquid chamber. The valve is rotatably disposed inside the regulating valve so that the inlet channel is connected to or not connected to different outlet channels. The valve drive mechanism includes a valve motor disposed on the regulating valve housing. The output shaft of the valve motor passes through the regulating valve housing and is fixedly connected to the valve. All the valve motors are electrically connected to the same controller disposed outside the upper and lower liquid chambers. The supporting partition is provided with a motor wiring channel leading to the outside, and a sealing mechanism is provided at the end of the motor wiring channel.

[0011] The regulating valve is provided with two outlet channels: a large outlet channel and a small outlet channel; a spherical hole is provided at the intersection of the inlet channel, the large outlet channel and the small outlet channel inside the regulating valve, and the valve includes a spherical surface corresponding to the spherical hole; a sealing mechanism is provided at the contact position between the valve motor and the housing of the regulating valve.

[0012] The support partition has a plurality of through holes evenly distributed along its circumference, and each through hole contains a regulating valve; the controller electrically connected to the valve motor is a valve motor controller fixedly installed on the circumferential side of the support partition; the valve motor controller is electrically connected to the vehicle controller, and the controller electrically connected to the drive motor is the vehicle controller.

[0013] The outer walls of the upper and lower liquid chambers are elastic. The lower end of the upper liquid chamber is fixed to the upper end of the supporting partition, and the upper end of the lower liquid chamber is fixed to the lower end of the supporting partition. A lower bracket connected to the vehicle body is fixedly installed at the lower end of the supporting partition. The lower liquid chamber is located inside the lower bracket. An upper bracket is fixedly installed at the upper end of the upper liquid chamber.

[0014] The upper liquid chamber is provided with a spring assembly in the vertical direction, and the spring assembly includes at least two springs of different lengths; as the upper support moves downward from the initial position, the springs of different lengths are compressed sequentially from longest to shortest.

[0015] The upper liquid chamber is formed by an upper elastic diaphragm and the supporting partition, and the lower liquid chamber is formed by a lower elastic diaphragm and the supporting partition. The upper support includes a mounting boss, a fixing boss, a support sealing cylinder, and a support shell. The support shell is disposed on the upper surface of the upper elastic diaphragm. A hollow cylindrical support sealing cylinder located inside the upper liquid chamber is disposed downward at the middle position of the support shell. The mounting boss for connecting the drive motor is disposed upward at the middle position of the support shell, and the fixing boss for mounting the upper end of the spring assembly is disposed downward at the middle position of the support shell. The fixing boss is located inside the support sealing cylinder. A hollow cylindrical partition sealing cylinder is disposed upward at the middle position of the supporting partition corresponding to the support sealing cylinder. The support sealing cylinder and the partition sealing cylinder are slidably connected and sealed by a sealing structure. The spring assembly is disposed within the space enclosed by the support sealing cylinder, the partition sealing cylinder, the supporting partition, and the fixing boss.

[0016] The spring assembly includes at least two springs of different lengths and stiffnesses; the greater the spring stiffness, the smaller the length; the upper end of the longest spring is fixed on the fixed boss, and the lower end is set on the support partition inside the partition sealing cylinder; the lower ends of the remaining springs smaller than the longest spring are set on the support partition inside the partition sealing cylinder.

[0017] The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque, the controller controls all regulating valves to open the channel with the smallest cross-sectional area. For large torque output, some regulating valves open the channel with the largest cross-sectional area, and some regulating valves open the channel with the smallest cross-sectional area. For small torque output, all regulating valves open the channel with the largest cross-sectional area.

[0018] The support partition is equipped with eight regulating valves, each including an inlet channel and two outlet channels: a large outlet channel and a small outlet channel. The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque output: at this time, the vehicle is accelerating at low speed with full throttle, and it is necessary to suppress the amplitude of the torsional vibration of the drive motor. The valve controller controls all eight regulating valves in the support partition to close the large outlet and open the small outlet channel. At this time, the fluid flow velocity is at its maximum, the damping force is at its maximum, and it can provide the drive motor with the maximum dissipation damping force, thereby suppressing the vibration amplitude of the motor to the greatest extent. For high torque output: at this time, the vehicle is accelerating with low throttle, and while providing a certain degree of suppression... While controlling the vibration amplitude of the drive motor, good vibration isolation performance is required. In the support partition, half of the valves in the eight channels are closed, with the large outlet channel closed and the small outlet channel open. The other half of the valves are closed, with the small outlet channel closed and the large outlet channel open. At this time, the fluid flow velocity and damping force are moderate. The fluid damping and the spring assembly work together to isolate vibration, providing good vibration isolation performance while suppressing the dissipation of motor vibration amplitude. For low torque output: when the whole vehicle is running at a constant speed or coasting, the best vibration isolation performance is required. All valves in the eight channels of the support partition are closed, with the small outlet channel closed and the large outlet channel open. At this time, the fluid flow velocity and damping force are minimal. The spring assembly acts as the main vibration isolation component, achieving optimal vibration isolation for the motor.

[0019] Beneficial effects: Compared with existing technologies, the invention patent effectively solves the low-frequency vibration isolation problem of the drive motor mounting system, while taking into account the needs of support and vibration amplitude suppression under high torque force of the motor, meeting the vibration isolation performance of the motor under various working conditions, and its reliability performance is significantly better than that of the current rubber mounts. Attached Figure Description

[0020] Figure 1 is a schematic diagram of the vibration isolation device of the present invention.

[0021] Figure 2 shows the upper support structure.

[0022] Figure 3 shows the lower support structure.

[0023] Figure 4 shows the supporting partition structure and motor wiring channel.

[0024] Figure 5 shows the distribution of control valves and the routing of valve motor circuits.

[0025] Figure 6 is a schematic diagram of the small outlet channel of the regulating valve being opened.

[0026] Figure 7 shows the structure of the regulating valve and the valve motor.

[0027] Figure 8 is a cross-sectional view along the AA direction of Figure 7.

[0028] Figure 9 shows the vibration isolation effect of the structure suspension of this invention when the torque is high (accelerating).

[0029] Figure 10 shows the vibration isolation effect of the structure suspension of the present invention when the torque output is small (uniform speed driving).

[0030] Figure 11 shows the effect of suppressing the vibration amplitude of the drive motor when the peak torque is output.

[0031] Figure 12 is a schematic diagram of the large outlet channel of the control valve being open.

[0032] The names of the components corresponding to the corresponding reference numerals in the figure are as follows: Upper elastic diaphragm 1, Upper support 2, Spring assembly 3, Sealing ring 4, Upper liquid chamber 5, Regulating valve 6, Support partition 7, Lower liquid chamber 8, Lower support 9, Lower elastic diaphragm 10, Support shell 21, Mounting boss 22, Fixing boss 23, Support sealing cylinder 24, Inlet channel 61, Large outlet channel 62, Small outlet channel 63, Valve 64, Valve motor 65, Partition sealing cylinder 71, Valve motor controller 72, Motor wiring 75, Motor wiring channel 76, Lower boss 91, Support shell 92, Bolt hole 93, Output shaft 650. Detailed Implementation

[0033] In this invention, unless otherwise expressly specified and limited, the technical terms used in this application shall have the ordinary meaning understood by those skilled in the art. Terms such as “connected,” “linked,” “fixed,” and “set” shall be interpreted broadly, referring to fixed connections, detachable connections, or integral connections; direct connections or indirect connections via an intermediate medium; mechanical connections or electrical connections. Unless otherwise expressly specified and limited, “above” or “below” a second feature may mean that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, “above,” “on top of,” or “on top of” a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. “Below,” “under,” or “beneath” a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. Relational terms such as “first,” “second,” etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms used in the description, such as “center,” “lateral,” “longitudinal,” “length,” “width,” “thickness,” “height,” “front,” “rear,” “left,” “right,” “up,” “down,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “axial,” “radial,” “circumferential,” “clockwise,” and “counterclockwise,” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0034] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. As shown in Figures 1-12, a drive motor vibration isolation device includes an upper liquid chamber 5 and a lower liquid chamber 8 disposed on the vehicle body and located below the drive motor. A supporting partition 7 is provided between the upper liquid chamber 5 and the lower liquid chamber 8 to separate them. At least one regulating valve 6 connecting the upper liquid chamber 5 and the lower liquid chamber 8 is provided on the supporting partition 7. The regulating valve 6 includes at least two channels with different cross-sectional areas. The valve 64 of the regulating valve 6 is driven by a valve 64 driving mechanism to switch the regulating valve 6 to different channels. The valve 64 driving mechanism and the drive motor are electrically connected to a controller. Here, the regulating valve 6 can be an electric regulating valve 6, a pneumatic regulating valve 6, etc., and the channel opening, closing, and channel switching are realized through the valve 64 driving mechanism. The valve 64 driving mechanism and the drive motor are connected to a controller, which can be a vehicle controller or other controllers. The controller automatically reads the output torque of the vehicle-mounted drive motor and realizes active control of the regulating valve 6 through different torque conditions. Of course, the controller can also control the regulating valve 6 through other parameters to switch between different channels. When the drive motor vibrates, the fluid in the upper liquid chamber 5 flows into the lower liquid chamber 8 through the channel in the regulating valve 6. After the regulating valve 6 switches to channels with different cross-sectional areas, different damping forces are generated during the fluid flow according to the flow velocity. This damping force acts on the supporting partition 7, dissipating the vibration energy of the supporting partition 7. The attenuated vibration is transmitted to the vehicle body, realizing vibration isolation and energy dissipation of the motor vibration.

[0035] Furthermore, the supporting partition 7 is provided with through holes, and at least one of the through holes is fixedly installed with the regulating valve 6. The regulating valve 6 includes an inlet channel 61 connecting the upper liquid chamber 5 and at least two outlet channels with different cross-sectional areas connecting the lower liquid chamber 8. The valve 64 is rotatably installed inside the regulating valve 6, allowing the inlet channel 61 to connect with or not connect with different outlet channels. The valve 64 drive mechanism includes a valve motor 65 installed on the housing of the regulating valve 6. The output shaft 650 of the valve motor 65 passes through the housing of the regulating valve 6 and is fixedly connected to the valve 64. All the valve motors 65 are electrically connected to the same controller installed outside the upper liquid chamber 5 and the lower liquid chamber 8. The supporting partition 7 is provided with a motor wiring channel 76 leading to the outside, and a sealing mechanism is provided at the end of the motor wiring channel 76. The valve motor 65 here can be a motor specifically for the valve 64, or it can be a commonly used motor, such as a servo motor. The valve motor 65 and the housing of the regulating valve 6 can be fixed by means of small screw connection, welding, bonding, etc. The through hole and the regulating valve 6 can be fixedly connected by interference fit or other means. The controller is preferably located outside the vibration isolation device, for example, fixed to the circumferential side of the supporting partition 7 by screws, but it can also be located elsewhere. The motor wiring channel 76 is preferably inverted L-shaped, with its end located on the circumferential side of the supporting partition 7, thus leading to the side of the vibration isolation device. The supporting partition 7 can have one or more motor wiring channels 76. Each motor wiring 75 can have its own motor wiring channel 76, or multiple motor wiring 75 can share one motor wiring channel 76. Preferably, all valve motors 65 wirings share the same motor wiring channel 76, as shown in the attached figure. The sealing mechanism at the end of the motor wiring channel 76 can be a sealing ring 4. The sealing ring 4 can be located in a sealing groove at the end of the motor wiring channel 76. The sealing mechanism can also be a sealing rubber strip located on the supporting partition 7 at the end of the motor wiring channel 76, with external pressure from a pressure strip or other structure.

[0036] Furthermore, the regulating valve 6 is provided with two outlet channels: a large outlet channel 62 and a small outlet channel 63; a spherical orifice is provided at the confluence of the inlet channel 61, the large outlet channel 62, and the small outlet channel 63 within the regulating valve 6, and the valve 64 includes a portion of the spherical surface corresponding to the spherical orifice; a sealing mechanism is provided at the contact position between the valve motor 65 and the housing of the regulating valve 6. The spherical orifice serves as a transfer station for the fluid channels of the upper and lower liquid chambers 8. The valve 64 includes a portion of the spherical surface, but not the entire spherical surface. The area or angle of the spherical surface of the valve 64 is determined as needed. The valve 64 can be optionally configured as a hollow hemispherical structure with a diameter slightly smaller than the diameter of the spherical orifice, achieving a shape fit, as shown in the attached diagram. The valve 64 is connected to the valve motor 65 via a miniature connecting shaft. The valve motor 65 drives the hemispherical valve 64 to rotate 180 degrees each time. Each rotation opens and closes the large outlet channel 62 and the small outlet channel 63. The valve motor 65 is mounted on the housing of the regulating valve 6. The wiring of the valve motor 65 is connected to the controller and wiring plug through the motor wiring channel 76 on the support partition 7 to transmit power and signals. The rotation angle of the valve motor 65 is controlled by the controller according to the magnitude of the drive motor torque, thereby opening and closing the large outlet channel 62 and the small outlet channel 63. This changes the flow velocity of the liquid in the upper liquid chamber 5 into the lower liquid chamber 8. Different liquid flow velocities provide different fluid damping forces. The positions of the large outlet channel 62 and the small outlet channel 63, and the shape of the valve 64 in the attached figure, enable the switching between the large outlet channel 62 and the small outlet channel 63. In practice, the relative positions of the inlet channel 61, the large outlet channel 62, and the small outlet channel 63 can be set as needed. Rotating the valve 64 allows for switching between connecting the inlet channel 61 and the large outlet channel 62, connecting the inlet channel 61 and the small outlet channel 63, connecting the inlet channel 61 and the large outlet channel 62 and the small outlet channel 63, and connecting none of them. For embodiments with more than two outlet channels, the above structure can also be used, namely a spherical orifice and a partially spherical valve 64. Furthermore, the shape of the inlet channel 61, the large outlet channel 62, and the small outlet channel 63 at their intersection within the regulating valve 6 can be other shapes, such as cylindrical, and the shape of the corresponding valve 64 can be changed accordingly. Additionally, the sealing mechanism between the valve motor 65 and the housing of the regulating valve 6 can be a sealing rubber strip used to seal the hole where the output shaft of the valve motor 65 is located.

[0037] Furthermore, the supporting partition 7 has a plurality of through holes evenly distributed along its circumference, and each through hole contains a regulating valve 6. The controller electrically connected to the valve motor 65 is a valve motor controller 72 fixedly mounted on the circumferential side of the supporting partition 7. The valve motor controller 72 is electrically connected to the vehicle controller, and the controller electrically connected to the drive motor is also the vehicle controller. The vehicle controller automatically reads the output torque of the on-board drive motor. The valve motor controller 72 controls the regulating valves 6, controlling the opening and closing of each channel according to the magnitude of the motor output torque, thereby controlling the fluid flow rate and achieving different damping forces. In the attached figure, the supporting partition 7 has 8 through holes, and the 8 regulating valves 6 improve the overall damping performance of the liquid. The valve motor controller 72 can independently control the valve motors 65 of each adaptive regulating valve 6, enabling the regulating valves 6 to operate in coordination. Of course, the number of regulating valves 6 can also be set to other numbers as needed.

[0038] Specifically, the outer walls of the upper liquid chamber 5 and the lower liquid chamber 8 are elastic. The lower end of the upper liquid chamber 5 is fixed to the upper end of the supporting partition 7, and the upper end of the lower liquid chamber 8 is fixed to the lower end of the supporting partition 7. A lower bracket 9 connecting to the vehicle body is fixedly installed at the lower end of the supporting partition 7. The lower liquid chamber 8 is located inside the lower bracket 9. An upper bracket 2 is fixedly installed at the upper end of the upper liquid chamber 5. The drive motor is located above the upper bracket 2, and the vibration of the motor is transmitted to the upper bracket 2. The attenuated vibration is then transmitted to the lower bracket 9 through a vibration damping device. Both the upper liquid chamber 5 and the lower liquid chamber 8 are elastic structures, and the liquid inside can flow between them as their volume changes. These are existing structures and will not be described in detail further.

[0039] Furthermore, a spring assembly 3 is provided in the upper liquid chamber 5 in the vertical direction. The spring assembly 3 includes at least two springs of different lengths. As the upper support 2 moves downward from its initial position, the springs of different lengths are compressed sequentially from longest to shortest. In this invention, a spring assembly 3 is provided in the upper liquid chamber 5, and multiple springs of different lengths form a parallel structure. In the initial state, only one end of some springs is fixed. When the upper support 2 first begins to move downward, generally only one spring is compressed, providing damping force, and at this time, the stiffness of the spring assembly 3 is relatively small. As the upper support 2 moves downward, the ends of the springs of different lengths begin to contact the upper and lower ends of the upper liquid chamber 5 and are compressed, and the stiffness of the springs providing damping force gradually increases. This invention patent employs multi-stage parallel springs as the main vibration isolation component and fluid damping as the auxiliary vibration isolation component. It determines the vehicle's operating condition by reading the torque output of the drive motor and adaptively adjusts the damping performance according to different conditions. This ensures that the vibration isolation device provides high damping and high stiffness under high motor torque conditions, supporting motor vibration isolation while limiting motor vibration amplitude; conversely, it ensures low damping and low stiffness under low motor torque conditions, reducing the natural frequency of the drive motor vibration isolation system and improving low-frequency vibration isolation. This invention uses a multi-stage spring structure to solve the problem of rubber structures being unable to withstand tensile forces, resulting in reliability far exceeding that of rubber vibration isolation devices currently on the market. Furthermore, the stiffness of the multi-stage spring structure can be achieved to within 300 N / mm, meeting low stiffness requirements.

[0040] The upper liquid chamber 5 is formed by the upper elastic diaphragm 1 and the supporting partition 7, and the lower liquid chamber 8 is formed by the lower elastic diaphragm 10 and the supporting partition 7; the upper bracket 2 includes a mounting boss 22, a fixing boss 23, a bracket sealing cylinder 24, and a bracket shell 9221; wherein the bracket shell 9221 is disposed on the upper surface of the upper elastic diaphragm 1, and a hollow cylindrical bracket sealing cylinder 24 located in the upper liquid chamber 5 is disposed downward at the middle position of the bracket shell 9221, and a component for connecting the drive motor is disposed upward at the middle position of the bracket shell 9221. Mounting boss 22 and downward-facing fixing boss 23 for mounting the upper end of the spring assembly 3 are located inside the bracket sealing cylinder 24. A hollow cylindrical partition sealing cylinder 71 is positioned upwards from the middle of the support partition 7, corresponding to the position of the bracket sealing cylinder 24. The bracket sealing cylinder 24 and the partition sealing cylinder 71 are slidably connected and sealed using a sealing structure. The spring assembly 3 is disposed within the space enclosed by the bracket sealing cylinder 24, the partition sealing cylinder 71, the support partition 7, and the fixing boss 23. The middle position here includes, but is not limited to, the very center position. Multiple sets of similar spring assemblies 3 with sealing structures can be disposed within the upper liquid chamber 5. These are all within the scope of protection of this invention. A sealing ring 4 can be used to achieve a sliding seal between the bracket sealing cylinder 24 and the partition sealing cylinder 71, isolating the liquid in the upper liquid chamber 5 from the spring assembly 3 and preventing liquid corrosion of the spring assembly 3. The drive motor is mounted on the mounting boss 22 of the upper bracket 2.

[0041] The spring assembly 3 includes at least two springs of different lengths and stiffnesses; the greater the stiffness of the spring, the shorter its length. The upper end of the longest spring is fixed to the fixed boss 23, and the lower end is set on the supporting partition 7 inside the partition sealing cylinder 71. The lower ends of the remaining springs, which are smaller than the longest spring, are set on the supporting partition 7 inside the partition sealing cylinder 71. In this invention, the spring with lower stiffness is longer, and the spring with higher stiffness is shorter. The spring vibration isolation component is composed of spring assemblies 3 of different stiffnesses connected in parallel, and the springs have different lengths, with the spring with lower stiffness being longer and the spring with higher stiffness being shorter. This structure ensures that under low torque conditions, the motor first contacts the lower stiffness spring and it provides support force. As the motor torque increases, the lower stiffness spring is continuously compressed until it contacts the higher stiffness spring. At this point, at least two springs, one large and one small, are connected in parallel to provide support stiffness. The spring vibration isolation component can be equipped with springs of different stiffnesses as needed, with the length decreasing sequentially, to ensure that the spring vibration isolation component can provide more than two types of vibration damping stiffness. Furthermore, the upper elastic diaphragm 1 and the lower elastic diaphragm 10 are made of rubber. The upper elastic diaphragm 1, the supporting partition 7, and the lower bracket 9 are connected by bolts. The upper bracket 2 is fixedly mounted on the upper end face and the upper side of the upper elastic module through vulcanization. A lower boss 91 is fixedly mounted in the middle position of the lower bracket 9. The lower end of the lower boss 91 passes through the lower bracket 9. The lower boss 91 can be fixedly connected to the vehicle body. Bolt holes 93 are provided on the lower bracket 9.

[0042] The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque, the controller controls all regulating valves 6 to open the channel with the smallest cross-sectional area. For large torque output, some regulating valves 6 open the channel with the largest cross-sectional area, and some regulating valves 6 open the channel with the smallest cross-sectional area. For small torque output, all regulating valves 6 open the channel with the largest cross-sectional area.

[0043] Eight regulating valves 6 are installed on the supporting partition 7. Each regulating valve 6 includes an inlet channel 61 and two outlet channels: a large outlet channel 62 and a small outlet channel 63. The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque output: at this time, the vehicle is accelerating at low speed with full throttle, and it is necessary to suppress the amplitude of the torsional vibration of the drive motor. The valve controller controls all eight regulating valves 64 in the supporting partition 7 to close the large outlet and open the small outlet channel 63. At this time, the fluid velocity is at its maximum, the damping force is at its maximum, and it can provide the drive motor with the maximum dissipation damping force, thereby suppressing the vibration amplitude of the motor to the greatest extent. For high torque output: at this time, the vehicle is accelerating with low throttle, and the controller provides a certain degree of suppression of the drive motor's torsional vibration. While controlling the vibration amplitude of the motor, good vibration isolation performance is required. In the support partition 7, half of the valves 64 in the eight channels are closed (large outlet channel 62, small outlet channel 63 is open), and the other half are closed (small outlet channel 63, large outlet channel 62 is open). At this point, the fluid flow velocity and damping force are moderate. The fluid damping and spring assembly 3 work together to isolate vibration, providing good vibration isolation performance while suppressing the dissipative motor vibration amplitude. For low torque output: when the vehicle is running at a constant speed or coasting, the best vibration isolation performance is required. In the support partition 7, all valves 64 in the eight channels are closed (small outlet channel 63, large outlet channel 62 is open). At this point, the fluid flow velocity and damping force are minimal, and the spring assembly 3 acts as the main vibration isolation component, achieving optimal vibration isolation for the motor. Specifically, the test results at peak torque are shown in Figure 11. The test results in the high torque output chamber are shown in Figure 9. The test results in the low torque output chamber are shown in Figure 10.

[0044] In practical implementation: When the drive motor operates at peak torque, the upper bracket 2 compresses the spring assembly 3 to the high stiffness position. At this time, multiple springs are connected in parallel for support. Simultaneously, the fluid in the upper liquid chamber 5 of the upper bracket 2 begins to flow into the lower liquid chamber 8. The regulating valve 6 adjusts the opening of valve 64 to open the channel with the smaller diameter and close the channel with the larger diameter. At this time, the fluid velocity is at its maximum, and the damping force generated is also at its maximum. The high stiffness spring and high damping provide greater support for the motor and dissipate vibration to the greatest extent, suppressing the motor vibration amplitude. When the motor operates at low torque, the upper bracket 2 compresses the spring assembly 3 to the low stiffness position. At this time, the longest spring is in contact, and the stiffness is at its minimum. Simultaneously, the fluid in the upper liquid chamber 5 of the upper bracket 2 flows into the lower liquid chamber 8. The adaptive regulating valve 6 adjusts the opening of valve 64 to open the channel with the larger diameter and close the channel with the smaller diameter. At this time, the fluid velocity is at its minimum, and the damping force generated is also at its minimum. The low stiffness spring and low damping reduce the natural frequency of the motor suspension system, achieving good vibration isolation performance of the motor at low frequencies. This invention effectively solves the low-frequency vibration isolation problem of drive motor mounting systems, while also taking into account the requirements for support and vibration amplitude suppression under high torque force of the motor. It meets the vibration isolation performance of the motor under various operating conditions, and its reliability performance is significantly better than that of current rubber mounts.

[0045] The technical features of the embodiments described above can be combined in any way, and as long as there is no contradiction in the combination of these technical features, they should all be considered within the scope of this specification. Without departing from the overall concept of this invention, any technical solutions based on this invention, as well as equivalent substitutions or modifications, and various changes and improvements made, should also be considered within the scope of protection of this invention.

Claims

1. A vibration isolation device for a drive motor, comprising an upper liquid chamber and a lower liquid chamber disposed on the vehicle body and located below the drive motor, wherein a supporting partition is disposed between the upper liquid chamber and the lower liquid chamber to separate the two; characterized in that: At least one regulating valve connecting the upper and lower liquid chambers is provided on the support partition; the regulating valve includes at least two channels with different cross-sectional areas, and the valve of the regulating valve is driven by a valve drive mechanism to switch the regulating valve to different channels; the valve drive mechanism and the drive motor are electrically connected to the controller.

2. The vibration isolation device for a drive motor according to claim 1, characterized in that: The supporting partition is provided with through holes, and at least one of the through holes is fixedly installed with a regulating valve. The regulating valve includes an inlet channel connecting the upper liquid chamber and at least two outlet channels with different cross-sectional areas connecting the lower liquid chamber. The valve is rotatably disposed inside the regulating valve so that the inlet channel is connected to or not connected to different outlet channels. The valve drive mechanism includes a valve motor disposed on the regulating valve housing. The output shaft of the valve motor passes through the regulating valve housing and is fixedly connected to the valve. All the valve motors are electrically connected to the same controller disposed outside the upper and lower liquid chambers. The supporting partition is provided with a motor wiring channel leading to the outside, and a sealing mechanism is provided at the end of the motor wiring channel.

3. The vibration isolation device for a drive motor according to claim 2, characterized in that: The regulating valve is provided with two outlet channels: a large outlet channel and a small outlet channel; a spherical hole is provided at the intersection of the inlet channel, the large outlet channel and the small outlet channel inside the regulating valve, and the valve includes a spherical surface corresponding to the spherical hole; a sealing mechanism is provided at the contact position between the valve motor and the housing of the regulating valve.

4. The vibration isolation device for a drive motor according to claim 2, characterized in that: The support partition has a plurality of through holes evenly distributed along its circumference, and each through hole contains a regulating valve; the controller electrically connected to the valve motor is a valve motor controller fixedly installed on the circumferential side of the support partition; the valve motor controller is electrically connected to the vehicle controller, and the controller electrically connected to the drive motor is the vehicle controller.

5. A vibration isolation device for a drive motor according to any one of claims 1-4, characterized in that: The outer walls of the upper and lower liquid chambers are elastic. The lower end of the upper liquid chamber is fixed to the upper end of the supporting partition, and the upper end of the lower liquid chamber is fixed to the lower end of the supporting partition. A lower bracket connected to the vehicle body is fixedly installed at the lower end of the supporting partition. The lower liquid chamber is located inside the lower bracket. An upper bracket is fixedly installed at the upper end of the upper liquid chamber.

6. The vibration isolation device for a drive motor according to claim 5, characterized in that: The upper liquid chamber is provided with a spring assembly in the vertical direction, and the spring assembly includes at least two springs of different lengths; as the upper support moves downward from the initial position, the springs of different lengths are compressed sequentially from longest to shortest.

7. A vibration isolation device for a drive motor according to claim 6, characterized in that: The upper liquid chamber is formed by an upper elastic diaphragm and a supporting partition, and the lower liquid chamber is formed by a lower elastic diaphragm and a supporting partition; the upper support includes a mounting boss, a fixing boss, a support sealing cylinder, and a support shell; The bracket shell is disposed on the upper surface of the upper elastic diaphragm. A hollow cylindrical bracket sealing cylinder located in the upper liquid chamber is disposed downward at the middle position of the bracket shell. An upward mounting boss for connecting the drive motor is disposed at the middle position of the bracket shell, and a downward fixing boss for mounting the upper end of the spring assembly is disposed at the middle position. The fixing boss is located inside the bracket sealing cylinder. A hollow cylindrical partition sealing cylinder is disposed upward at the middle position of the support partition corresponding to the bracket sealing cylinder. The bracket sealing cylinder and the partition sealing cylinder are slidably connected and sealed by a sealing structure. The spring assembly is disposed within the space enclosed by the bracket sealing cylinder, the partition sealing cylinder, the support partition, and the fixing boss.

8. A vibration isolation device for a drive motor according to claim 7, characterized in that: The spring assembly includes at least two springs of different lengths and stiffnesses; the greater the spring stiffness, the smaller the length; the upper end of the longest spring is fixed on the fixed boss, and the lower end is set on the support partition inside the partition sealing cylinder; the lower ends of the remaining springs smaller than the longest spring are set on the support partition inside the partition sealing cylinder.

9. A control strategy for a drive motor vibration isolation device according to any one of claims 1-8, characterized in that: The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque, the controller controls all regulating valves to open the channel with the smallest cross-sectional area; for high torque output, some regulating valves open the channel with the largest cross-sectional area, and some regulating valves open the channel with the smallest cross-sectional area. For low torque output, all regulating valves open the channel with the largest cross-sectional area.

10. The control strategy of the adaptive vibration isolation device according to any one of claims 6-8, characterized in that: The support partition is equipped with eight regulating valves, each of which includes an inlet channel and two outlet channels: a large outlet channel and a small outlet channel. The controller reads the output torque value of the drive motor and determines the magnitude of the output torque force. For peak torque output: At this time, the vehicle is accelerating at low speed with full throttle. It is necessary to suppress the amplitude of torsional vibration of the drive motor. The valve controller controls all eight regulating valves in the support baffle to close the large outlet and open the small outlet channel. At this time, the fluid velocity is at its maximum, and the damping force is at its maximum, providing the drive motor with the maximum dissipative damping force, thereby suppressing the motor's vibration amplitude to the greatest extent. For high torque output: At this time, the vehicle is accelerating with low throttle. While providing a certain degree of suppression of the drive motor's vibration amplitude, good vibration isolation performance is required. Half of the eight channels in the support baffle... With the large outlet channel closed and the small outlet channel open, and the other half of the valves closed the small outlet channel and opened the large outlet channel, the fluid flow velocity and damping force are moderate. The fluid damping and the spring assembly work together to isolate vibration, providing good vibration isolation performance while suppressing the vibration amplitude of the dissipative motor. For low torque output: when the vehicle is running at a constant speed or coasting, the best vibration isolation performance is required. All valves in the eight channels of the support baffle are closed in the small outlet channel and opened in the large outlet channel. At this time, the fluid flow velocity and damping force are minimal, and the spring assembly acts as the main vibration isolation component, achieving optimal vibration isolation for the motor.

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