Vehicle-mounted electrical device, power assembly and vehicle

Abstract

The utility model provides a vehicle-mounted electrical device, a power assembly and a vehicle, a shell of the vehicle-mounted electrical assembly comprises a groove-shaped bottom shell and a rectangular cover plate, the rectangular cover plate is used for being stacked on the groove-shaped bottom shell to form a containing cavity, and the containing cavity is used for containing electrical components. The rectangular cover plate comprises an annular protrusion, a plurality of fixing holes, a plurality of strip-shaped protrusions and two bending areas. The fixing holes surround the annular protrusion and penetrate through the rectangular cover plate, the fixing holes are used for penetrating through fixing pieces, and the fixing pieces are used for being fixedly connected with the end face, facing one rectangular cover plate, of the groove-shaped bottom shell. The strip-shaped protrusions extend from the periphery of the annular protrusion to the periphery of the rectangular cover plate. The two bending areas are distributed on the two sides of the annular protrusion, the bending areas incline towards the end face of the groove-shaped bottom shell, and each bending area is used for bending at least one strip-shaped protrusion. Through cooperation of the annular protrusion, the strip-shaped protrusion, the bending area and the like in the cover plate, frequency avoiding between the cover plate and the excitation source is achieved, and the vibration and noise reduction effect is enhanced.

Description

Technical Field

[0001] This application relates to the field of electric vehicle technology, and in particular to an on-board electrical device, powertrain, and vehicle. Background Technology

[0002] In the new energy vehicle industry, NVH (Noise, Vibration, and Harshness) performance is of paramount importance to improving ride comfort. The powertrain is one of the main sources of vehicle vibration and noise. The powertrain includes the electric motor. During operation, both the motor shaft and the input shaft of the reducer rotate, making vibration unavoidable. This vibration not only affects the normal operation of the vehicle's electrical systems but can also radiate throughout the vehicle. Therefore, it is crucial to improve the vibration and noise reduction performance of the vehicle's electrical systems to reduce overall powertrain vibration and noise, ensure proper powertrain operation, and enhance the vehicle's NVH performance. Utility Model Content

[0003] This application provides an on-board electrical device, powertrain, and vehicle that can improve vibration and noise reduction performance.

[0004] In a first aspect, embodiments of this application provide a vehicle-mounted electrical device. The housing of the vehicle-mounted electrical device includes a groove-shaped bottom shell and a rectangular cover plate. The rectangular cover plate is stacked on the groove-shaped bottom shell to form a receiving cavity. The receiving cavity is used to accommodate multiple electrical components of the vehicle-mounted electrical device. The rectangular cover plate includes an annular protrusion, multiple fixing holes, multiple strip-shaped protrusions, and two bending areas.

[0005] The direction of the annular protrusion is opposite to that of a receiving cavity, which is along the stacking direction of a rectangular cover plate and a trough-shaped bottom shell.

[0006] Multiple fixing holes surround an annular protrusion. Each fixing hole penetrates a rectangular cover plate along the stacking direction of a rectangular cover plate and a channel-shaped bottom shell. Each fixing hole is used to pass through a fixing member. Each fixing member is used to fix the end face of the channel-shaped bottom shell facing a rectangular cover plate.

[0007] Each strip protrusion extends from the outer periphery of an annular protrusion toward the periphery of a rectangular cover plate, and the protrusion direction of each strip protrusion is opposite to a receiving cavity along the stacking direction of a rectangular cover plate and a groove-shaped bottom shell.

[0008] Two bending regions are distributed on both sides of an annular protrusion. Each bending region is inclined toward the end face of a groove-shaped bottom shell, and each bending region is used to bend at least one strip protrusion.

[0009] In this embodiment, a slotted bottom shell and a rectangular cover plate of the vehicle electrical device are used to enclose a receiving cavity. The slotted bottom shell is a recessed bottom shell. It is understood that the shape of the rectangular cover plate is not strictly limited to a rectangle; the rectangle primarily indicates that the rectangular cover plate has both length and width directions.

[0010] In this embodiment, multiple fixing holes are used to securely connect a rectangular cover plate and a channel-shaped bottom shell. Along the stacking direction of the rectangular cover plate and the channel-shaped bottom shell, the multiple fixing holes of the rectangular cover plate face the end face of the channel-shaped bottom shell. The multiple fixing holes surround an annular protrusion, which helps to improve the connection strength between the rectangular cover plate and the channel-shaped bottom shell. In one embodiment, the distance between each fixing hole and an electrical component within the receiving cavity along the stacking direction of the rectangular cover plate and the channel-shaped bottom shell is less than the distance between the annular protrusion and the electrical component.

[0011] In this embodiment, a rectangular cover plate is subjected to vibration from an excitation source. Resonance occurs when the natural vibration frequency of the rectangular cover plate is close to the vibration frequency of the excitation source. Therefore, it is necessary to adjust the natural vibration frequency of the rectangular cover plate to achieve frequency avoidance between the cover plate and the excitation source. The natural vibration frequency is an inherent property of the vibration system, related to the system's mass and stiffness, and its magnitude is proportional to the stiffness. Based on the number of degrees of freedom of the system, resonance can be divided into different orders of resonance, with the vibration frequency gradually increasing from the first order to higher orders, meaning the first order vibration frequency is the smallest among all orders. Currently, the commonly used frequency avoidance method in the covers of vehicle electrical devices is to increase the first order vibration frequency of the cover plate. However, with continuous structural improvements and refinements, the space for increasing the first order vibration frequency is limited. Further increasing the first order vibration frequency of the cover plate on the existing basis is quite difficult, and increasing the first order vibration frequency is unlikely to achieve frequency avoidance between the cover plate and the motor shaft or reducer input shaft in the powertrain.

[0012] To address the aforementioned issues, this application embodiment uses an annular protrusion on a rectangular cover plate to reduce the first-order vibration frequency of the rectangular cover plate, thereby alleviating the first-order resonance problem of the rectangular cover plate.

[0013] In this embodiment, an annular protrusion has an inner wall and an outer wall, and the inner wall of the annular protrusion can form a cavity. Compared to a columnar annular protrusion, this embodiment is advantageous in reducing the stiffness of a rectangular cover plate, thereby reducing the first-order vibration frequency of the rectangular cover plate, widening the gap between the first-order vibration frequency of the rectangular cover plate and the vibration frequency of the excitation source, and reducing the number of times the rectangular cover plate resonates.

[0014] In this embodiment, an annular protrusion not only reduces the first-order vibration frequency but also lowers higher-order vibration frequencies, such as the fifth or sixth-order frequencies. If a rectangular cover plate only includes an annular protrusion, the lowered higher-order vibration frequencies will be difficult to avoid oscillating with the excitation source. Specifically, in a rectangular cover plate, the region with the largest amplitude of higher-order vibration modes is concentrated at the edge of the cover plate.

[0015] To counteract the influence of a ring-shaped protrusion on higher-order vibration frequencies, a rectangular cover plate according to an embodiment of this application further includes multiple strip-shaped protrusions and two bending regions. The multiple strip-shaped protrusions and two bending regions can all improve the stiffness of a local area of ​​the rectangular cover plate. Specifically, one end of each strip-shaped protrusion is connected to the outer wall of the ring-shaped protrusion, and the other end of each strip-shaped protrusion extends towards the perimeter of the rectangular cover plate. The two bending regions are arranged on both sides of a ring-shaped protrusion, and at least one strip-shaped protrusion extends into one of the bending regions. That is, each strip-shaped protrusion and each bending region is closer to the edge of the rectangular cover plate than a ring-shaped protrusion, which helps maintain the higher-order vibration frequencies of the rectangular cover plate.

[0016] In this embodiment, an annular protrusion reduces the first-order vibration frequency of a rectangular cover plate. Multiple strip protrusions and two bent areas are arranged around the outer periphery of the annular protrusion. These protrusions and areas increase the higher-order vibration frequencies of the rectangular cover plate, thus offsetting the effect of the annular protrusion in reducing these frequencies. In other words, this embodiment, through the cooperation of an annular protrusion, multiple strip protrusions, and two bent areas on a rectangular cover plate, widens the gap between the first-order vibration frequency and the vibration frequency of the excitation source without negatively impacting higher-order vibration frequencies, thereby improving the vibration reduction and noise reduction performance of the rectangular cover plate. Furthermore, this embodiment requires minimal structural modification to the rectangular cover plate, reducing the need for modifications to other structures of the vehicle's electrical system to accommodate the rectangular cover plate, which helps reduce processing difficulty and cost.

[0017] In one embodiment, a rectangular cover plate is a constrained damping structure. The rectangular cover plate includes a base layer, a metal layer, and a damping layer located between the base layer and the metal layer. Along the stacking direction of the rectangular cover plate and the channel-shaped bottom shell, the distance between the base layer and the electrical components is less than the distance between the constrained layer and the electrical components. The Young's modulus of the damping layer is less than the Young's modulus of either the base layer or the metal layer. Young's modulus refers to the ability to resist deformation.

[0018] In this embodiment, when a rectangular cover plate is subjected to vibration, since the Young's modulus of both the base layer and the metal layer is greater than that of the damping layer, the base layer and the constraint layer can impede the tensile and bending deformation of the damping layer, causing shear deformation to occur within the damping layer. Because shear deformation consumes more energy than tensile and bending deformation, the base layer and the constraint layer can improve the damping layer's energy dissipation effect. The rectangular cover plate in this embodiment, being a constraint-damped structure, is beneficial for improving vibration reduction and noise reduction performance, and reducing the negative impact of vibration on electrical components.

[0019] In one embodiment, the ratio of the distance between the center of an annular protrusion and the center of the rectangular cover plate along the width direction of the rectangular cover plate to the width of the rectangular cover plate is less than or equal to 1 / 5, and the ratio of the distance between the center of an annular protrusion and the center of the rectangular cover plate along the length direction of the rectangular cover plate to the length of the rectangular cover plate is less than or equal to 1 / 4.

[0020] In this embodiment, the cover plate of the vehicle electrical device is typically a thin plate structure. The first-order vibration mode of a thin plate structure exhibits the characteristic of maximum amplitude at the center, with the amplitude decreasing radially from the center to the edge. The position of an annular protrusion within a rectangular cover plate affects its effect on reducing the first-order vibration frequency. If the center of an annular protrusion is far from the center of a rectangular cover plate, the amplitude of the region containing the annular protrusion is relatively smaller than the amplitude at the center of the rectangular cover plate, which is detrimental to the annular protrusion's function of adjusting the vibration frequency of the rectangular cover plate.

[0021] In this embodiment, by adjusting the position of an annular protrusion on a rectangular cover plate and shortening the distance between the annular protrusion and the center of the rectangular cover plate, the stiffness of the region with the largest amplitude in the rectangular cover plate is reduced. This effectively lowers the first-order vibration frequency of the rectangular cover plate, achieving frequency avoidance between the rectangular cover plate and the excitation source, and alleviating the resonance problem. In one embodiment, the annular protrusion is integrally die-cast into a rectangular cover plate. In this embodiment, the center of the annular protrusion is close to the center of the rectangular cover plate, which also helps to reduce the difficulty and cost of die-casting the annular protrusion.

[0022] In one embodiment, the ratio of the inner diameter of an annular protrusion to the outer diameter of an annular protrusion is greater than or equal to 5 / 6, and the ratio of the inner diameter of an annular protrusion to the outer diameter of an annular protrusion is less than or equal to 8 / 9. Along the width direction of a rectangular cover plate, the ratio of the outer diameter of an annular protrusion to the width of the rectangular cover plate is greater than or equal to 1 / 3.

[0023] In this embodiment, a larger ratio of the inner diameter to the outer diameter of an annular protrusion, and a larger ratio of the outer diameter of an annular protrusion to the width of a rectangular cover plate, will result in a larger volume of the inner void of the annular protrusion. This will make the reduction in stiffness of the rectangular cover plate more significant, which is beneficial for increasing the amplitude of the first-order vibration frequency change. Furthermore, a larger ratio of the inner diameter to the outer diameter of an annular protrusion will also result in a smaller volume of the annular protrusion. This avoids increasing the stiffness of the central region of the rectangular cover plate due to an excessively large volume of the annular protrusion, thus preventing a negative impact on the effect of the annular protrusion in reducing the first-order vibration frequency.

[0024] In one embodiment, a plurality of strip protrusions are spaced apart on the outer periphery of an annular protrusion along its circumference, and the width of each strip protrusion along the circumference of the annular protrusion is greater than the difference between the outer diameter and the inner diameter of the annular protrusion.

[0025] In this embodiment, multiple strip protrusions are used to counteract the influence of a ring protrusion on the higher-order vibration frequencies of a rectangular cover plate. The multiple strip protrusions are arranged at circumferential intervals along the outer periphery of the ring protrusion. The width of each strip protrusion along the circumferential direction of the ring protrusion is greater than the difference between the inner and outer diameters of the ring protrusion. This arrangement, both in terms of position and circumferential size, expands the coverage area of ​​the multiple strip protrusions on the rectangular cover plate, which is beneficial for the multiple strip protrusions to maintain the higher-order vibration frequencies of the rectangular cover plate.

[0026] In one embodiment, the minimum distance between each strip protrusion and a fixing hole is greater than or equal to the minimum distance between a bend and a fixing hole. The width of each strip protrusion along the circumference of an annular protrusion is greater than the minimum distance between a bend and a fixing hole.

[0027] In this embodiment, the strip protrusions and the fixing holes are arranged at intervals, and the strip protrusions are far away from the fixing holes relative to the bending area, so as to avoid the strip protrusions interfering with the fixing effect of the fixing holes.

[0028] In this embodiment, the width of the strip protrusion is compared with the minimum distance between the bending area and the fixing hole. The relatively large width of the strip protrusion can improve the stiffness of the area where the strip protrusion is located, thereby increasing the higher-order vibration frequency. The relatively small minimum distance between the bending area and the fixing hole is beneficial for controlling the overall size of the rectangular cover plate, so as to realize the miniaturization design of the vehicle electrical device.

[0029] In one embodiment, the ratio of the thickness of the outer wall of an annular protrusion to the thickness of the rectangular cover plate excluding the annular protrusion and the plurality of strip protrusions along the stacking direction of a rectangular cover plate and a grooved bottom shell is less than or equal to 3 / 4.

[0030] The embodiments of this application help to avoid the negative impact of excessive outer wall thickness of an annular protrusion on the reduction of stiffness of the annular protrusion, and can also control the overall thickness of a rectangular cover plate, which is conducive to the miniaturization design of vehicle electrical devices.

[0031] In one embodiment, the thickness of the outer wall of an annular protrusion along the stacking direction of a rectangular cover plate and a grooved bottom shell is greater than or equal to the thickness of each strip protrusion.

[0032] In this embodiment, the thickness of the outer wall of an annular protrusion is compared with the thickness of each strip protrusion: the relatively larger thickness of the outer wall of the annular protrusion is beneficial for the annular protrusion to reduce the stiffness of the rectangular cover plate, thereby increasing the difference between the first-order vibration frequency of the rectangular cover plate and the vibration frequency of the excitation source. One end of each strip protrusion is connected to the outer wall of an annular protrusion, and the relatively smaller thickness of each strip protrusion is beneficial for improving the connection strength between each strip protrusion and the annular protrusion, and also for reducing costs.

[0033] In one embodiment, the inner wall of an annular protrusion is used to form a groove with a portion of one surface of a rectangular cover plate, the portion of the surface being located on the inner periphery of the annular protrusion, the portion of the surface being recessed toward a receiving cavity along the stacking direction of the rectangular cover plate and the trough-shaped bottom shell, and the groove depth of the groove being greater than the thickness of the outer wall of the annular protrusion along the stacking direction of the rectangular cover plate and the trough-shaped bottom shell.

[0034] In the embodiments of this application, a portion of a surface along the stacking direction of a rectangular cover plate and a grooved bottom shell is recessed relative to the outer wall of an annular protrusion toward the electrical component, which can achieve a frequency avoidance effect between the rectangular cover plate and the excitation source by reducing the stiffness of the rectangular cover plate.

[0035] In one embodiment, the ratio of the depth of a portion of a surface recess along the stacking direction of a rectangular cover plate and a grooved bottom shell to the thickness of the rectangular cover plate excluding an annular protrusion and a plurality of strip protrusions is less than or equal to 1 / 4.

[0036] In this embodiment, the greater the depth of the groove formed by the inner wall of an annular protrusion and a portion of a surface, the lower the stiffness of the rectangular cover. However, the groove depth also needs to consider the damping performance of the rectangular cover itself and the clearance between it and electrical components. Therefore, this embodiment controls the ratio of the recess depth of the portion of a surface used to form a groove to the thickness of the rectangular cover excluding the annular protrusion and multiple strip protrusions to be less than or equal to 1 / 4. This helps to avoid negatively impacting the damping effect of the rectangular cover and also prevents the rectangular cover from compressing the space in the receiving cavity used to house electrical components.

[0037] In one embodiment, the width of a portion of a surface along the width direction of a rectangular cover plate is less than or equal to the inner diameter of an annular protrusion, and the length of a portion of a surface along the length direction of a rectangular cover plate is less than or equal to the inner diameter of an annular protrusion.

[0038] In this embodiment, a recessed portion facing the electrical component can be spaced apart from the inner wall of an annular protrusion. Structurally, the width and length of the groove bottom are smaller than the inner diameter of the annular protrusion. This balances reducing the stiffness of the rectangular cover while avoiding affecting its damping performance and ensuring the cover avoids obstructing electrical components, thus improving the practicality of the rectangular cover. The inner wall of the annular protrusion and the groove bottom can be integrally machined, such that the width and length of the groove bottom are equal to the inner diameter of the annular protrusion.

[0039] In one embodiment, the minimum angle between each bending region and the end face of a grooved bottom shell is greater than or equal to 10 degrees, and the minimum angle between each bending region and the end face of a grooved bottom shell is less than or equal to 45 degrees.

[0040] In this embodiment, the angle between each bending region and the end face of a channel-shaped bottom shell has a significant impact on maintaining higher-order vibration frequencies. If the angle between a bending region and the end face of a channel-shaped bottom shell is too small, the two ends will be approximately coplanar, making it difficult for the bending region to improve the local stiffness of the rectangular cover plate, resulting in a negligible increase in higher-order vibration frequencies. If the angle between a bending region and the end face of a channel-shaped bottom shell is too large, it will affect the overall thickness of the rectangular cover plate, causing an excessive reduction in the first-order vibration frequency. Furthermore, the structure of the channel-shaped bottom shell needs to be adjusted to match the rectangular cover plate, leading to excessive costs. This embodiment, by adjusting the range of the angle between each bending region and the end face of a channel-shaped bottom shell, helps to alleviate the above problems.

[0041] In one embodiment, two bending regions are distributed on both sides of an annular protrusion along the length of a rectangular cover plate. The length of each bending region in the two bending regions along the length of the rectangular cover plate is greater than the outer diameter of the annular protrusion, and the length of each bending region in the two bending regions along the length of the rectangular cover plate is less than the maximum distance between the centers of the two fixing holes.

[0042] In this embodiment, the two bending regions enhance the local stiffness of the rectangular cover plate containing these regions, thus offsetting the effect of the annular protrusion in reducing higher-order vibration frequencies. The length of each bending region is greater than the outer diameter of the annular protrusion, ensuring that the two bending regions effectively enhance higher-order vibration frequencies. The length of each bending region is less than the maximum distance between the centers of the two fixing holes along the length of the rectangular cover plate, preventing the two bending regions from negatively impacting the connection stability between the rectangular cover plate and the grooved bottom shell.

[0043] In one embodiment, a rectangular cover plate further includes two additional bending regions distributed on both sides of an annular protrusion along the width direction of the rectangular cover plate. The width of each of the two additional bending regions along the width direction of the rectangular cover plate is greater than the outer diameter of the annular protrusion, and the width of each of the two additional bending regions along the width direction of the rectangular cover plate is less than the maximum distance between the centers of the two fixing holes.

[0044] In this embodiment, the four bending regions are arranged on different sides of the annular protrusion, which helps to enhance the effect of the bending regions in raising the higher-order vibration frequency, expand the range of local stiffness improvement in a rectangular cover plate, and avoid the higher-order vibration frequency of a rectangular cover plate from the vibration frequency of the excitation source, thereby alleviating the problem of resonance in a rectangular cover plate.

[0045] In this embodiment, the width of each of the other two bending regions is greater than the outer diameter of an annular protrusion, which helps ensure that the other two bending regions play a role in enhancing higher-order vibration frequencies. The width of the other two bending regions is less than the maximum distance between the centers of the two fixing holes along the width direction of the rectangular cover plate, which can prevent the other two bending regions from negatively affecting the connection stability between the rectangular cover plate and the grooved bottom shell.

[0046] Secondly, embodiments of this application provide a powertrain, which includes a motor, a reducer, and an on-board electrical device as described in any embodiment of the first aspect. The on-board electrical device is used to transmit electrical energy to the motor through multiple electrical components, and the motor is used to convert electrical energy into mechanical energy and transmit the mechanical energy to the reducer.

[0047] In this embodiment of the application, the vehicle electrical device of the first aspect is applied to the powertrain. Since the cover of the vehicle electrical device can effectively avoid the excitation source and has excellent vibration reduction effect, it is beneficial to ensure the normal operation of each component in the powertrain and avoid electrical faults caused by vibration.

[0048] Thirdly, embodiments of this application provide a vehicle, which includes a frame, a battery pack, and a powertrain as described in the first aspect. The frame is used to fix the battery pack and the powertrain. The battery pack is used to provide electrical energy to the motor in the powertrain through on-board electrical devices. The powertrain is used to drive the wheels of the vehicle.

[0049] In this embodiment of the application, the powertrain of the second aspect is applied to a vehicle. Since the on-board electrical devices in the powertrain can block the propagation of vibration within the powertrain, it is beneficial to improve the NVH performance of the whole vehicle. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0051] Figure 1 This is a schematic diagram of the vehicle structure provided in the embodiments of this application;

[0052] Figure 2 This is a schematic diagram of the powertrain provided in the embodiments of this application;

[0053] Figure 3 This is a cross-sectional view of the vehicle-mounted electrical device provided in the embodiments of this application;

[0054] Figure 4 This is a top view of a rectangular cover plate provided in an embodiment of this application;

[0055] Figure 5 This is a cross-sectional view of the rectangular cover plate provided in an embodiment of this application;

[0056] Figure 6 This is another top view of the rectangular cover plate provided in the embodiments of this application. Detailed Implementation

[0057] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0058] For ease of understanding, the English abbreviations and related technical terms used in the embodiments of this application will be explained and described below.

[0059] Mode: refers to the inherent vibration characteristics of a structure or system. Each mode has a specific natural vibration frequency, damping ratio and mode shape.

[0060] Young's modulus: refers to the ratio of strain to stress, used to describe the ability of a solid material to resist deformation, and its unit is GPa.

[0061] Parallelism: The parallelism defined in the embodiments of this application is not limited to absolute parallelism. This definition of parallelism can be understood as basic parallelism, allowing for situations where the parallelism is not absolute due to factors such as assembly tolerance, design tolerance, and structural flatness.

[0062] Perpendicularity: The perpendicularity defined in the embodiments of this application is not limited to an absolute perpendicular intersection relationship. It is permissible for non-absolute perpendicular intersection relationships caused by factors such as assembly tolerance, design tolerance, and structural flatness. It is permissible for errors within a small angular range, such as an assembly error range of 80 to 100 degrees, which can all be understood as a perpendicular relationship.

[0063] NVH: An abbreviation for Noise, Vibration, and Harshness, referring to noise, vibration, and acoustic roughness, used to measure the quality of automotive design and manufacturing.

[0064] The vibration modes of current vehicle-mounted electrical devices are easily excited by excitation sources, and their vibration reduction and noise reduction performance needs improvement. This application provides a vehicle-mounted electrical device whose housing includes a channel-shaped bottom shell and a rectangular cover plate. The rectangular cover plate is stacked on the channel-shaped bottom shell to form a receiving cavity, which accommodates multiple electrical components of the vehicle-mounted electrical device. The rectangular cover plate has a length direction and a width direction.

[0065] A rectangular cover plate includes an annular protrusion, multiple fixing holes, multiple strip protrusions, and two bending areas.

[0066] An annular protrusion is oriented away from a receiving cavity along the stacking direction of a rectangular cover plate and a channel-shaped bottom shell. The annular protrusion is used to reduce the first-order vibration frequency of the rectangular cover plate. Multiple fixing holes surround the annular protrusion. Each fixing hole penetrates the rectangular cover plate along the stacking direction of the rectangular cover plate and the channel-shaped bottom shell, and each fixing hole is used to pass through a fixing member. Each fixing member is used to securely connect the end face of the channel-shaped bottom shell facing the rectangular cover plate.

[0067] Each strip-shaped protrusion extends from the outer periphery of an annular protrusion toward the periphery of a rectangular cover plate. The protrusion direction of each strip-shaped protrusion is opposite to a receiving cavity along the stacking direction of a rectangular cover plate and a channel-shaped bottom shell. Two bending regions are distributed on both sides of an annular protrusion, each bending region inclined toward the end face of a channel-shaped bottom shell, and each bending region is used to bend at least one strip-shaped protrusion. The strip-shaped protrusions and bending regions are used to counteract the effect of the annular protrusion in reducing higher-order vibration frequencies, thereby maintaining the higher-order vibration frequencies of the rectangular cover plate.

[0068] This application embodiment adjusts the natural vibration frequency of the cover plate of the vehicle electrical device by coordinating annular protrusions, strip protrusions, and bending areas. This achieves frequency avoidance between the cover plate and the excitation source, which helps alleviate the resonance problem of the cover plate and improves the vibration reduction and noise reduction performance of the vehicle electrical device. The vehicle electrical device provided in this application embodiment can be applied to a powertrain, and a powertrain containing the vehicle electrical device of this application can be applied to a vehicle.

[0069] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1 provided in an embodiment of this application. In this embodiment, vehicle 1 refers to a wheeled device driven or towed by a power unit. In this embodiment, vehicle 1 includes a frame 20, a battery pack 30, and a powertrain 10. The frame 20 is the structural skeleton of vehicle 1, used to fix the battery pack 30 and the powertrain 10, and capable of withstanding the loads from the internal and external environment of vehicle 1. The battery pack 30 is used to supply power to the powertrain 10; the battery pack 30 can also be referred to as a power battery. The powertrain 10 is the power source of vehicle 1, and is used to drive the wheels 40 of vehicle 1.

[0070] Please see Figure 2 , Figure 2 This is a schematic diagram of the powertrain 10 provided in an embodiment of this application. In this embodiment, the powertrain 10 includes an on-board electrical device 100, a motor 200, and a reducer 300. The motor 200 is used to convert electrical energy into mechanical energy, and the motor 200 is connected to the reducer 300 to drive the wheels 40 to rotate. It should be noted that... Figure 2 The structure of the on-board electrical device 100 in the powertrain 10 is shown only schematically and does not represent its specific size, shape, or positional relationship with the motor 200 and the reducer 300.

[0071] In one embodiment, the vehicle electrical system 100 includes at least one of a motor controller, an on-board charger, or an on-board power distribution device. The motor controller converts direct current (DC) transmitted from the battery pack into alternating current (AC) and transmits the AC power to the motor. The on-board charger receives electrical energy from an external power source and charges the battery pack. The on-board power distribution device distributes the electrical energy output from the battery pack to the vehicle's loads.

[0072] The motor controller, on-board charger, and on-board power distribution unit all involve the function of AC / DC conversion or power conversion using electrical component 140. For example, electrical component 140 includes a capacitor module and a power module. The capacitor module is electrically connected between the battery pack and the power module, and can smooth voltage, reduce inductance parameters, and weaken voltage spikes. The power module refers to a combination of power electronic devices capable of power conversion, including at least one of an insulated-gate bipolar transistor (IGBT), a silicon carbide power transistor, a silicon transistor, a metal-oxide-semiconductor field-effect transistor (MOSFET), and a diode.

[0073] During vehicle operation, the on-board electrical system is subjected to vibrations from the motor and reducer. If the cover of the on-board electrical system is easily excited and resonates, it will radiate noise externally and interfere with the electrical connections of electrical components internally, negatively impacting the normal operation of the on-board electrical system and powertrain.

[0074] This application embodiment improves the structure of the cover plate in the vehicle electrical device and adjusts the natural vibration frequency of the cover plate to achieve frequency avoidance between the cover plate and the excitation source, thereby enhancing the vibration reduction and noise reduction performance of the vehicle electrical device and alleviating the vehicle's NVH problems.

[0075] Please see Figure 3 and Figure 4 , Figure 3 This is a cross-sectional view of the vehicle electrical device 100 provided in an embodiment of this application. Figure 4 This is a top view of a rectangular cover plate 110 provided in an embodiment of this application. For simplicity, Figure 3 The cross-sectional lines are omitted.

[0076] like Figure 3 As shown, the housing 101 of the vehicle electrical device 100 includes a channel-shaped bottom shell 120 and a rectangular cover plate 110. The rectangular cover plate 110 is stacked on the channel-shaped bottom shell 120 to form a receiving cavity 130, which is used to receive a plurality of electrical components 140 of the vehicle electrical device 100.

[0077] like Figure 3 and Figure 4As shown, a rectangular cover plate 110 includes an annular protrusion 111, multiple fixing holes 112, multiple strip-shaped protrusions 113, and two bending regions 114. The protrusion direction of the annular protrusion 111 is opposite to that of a receiving cavity 130 along the stacking direction of the rectangular cover plate 110 and the groove-shaped bottom shell 120. Figure 4 As shown, multiple fixing holes 112 surround an annular protrusion 111. Figure 3 As shown, each fixing hole 112 penetrates a rectangular cover plate 110 along the stacking direction of a rectangular cover plate 110 and a grooved bottom shell 120. Each fixing hole 112 is used to pass through a fixing member, and each fixing member is used to fix a grooved bottom shell 120 to the end face 121 facing a rectangular cover plate 110.

[0078] like Figure 4 As shown, each strip-shaped protrusion 113 extends from the outer periphery of an annular protrusion 111 toward the periphery of a rectangular cover plate 110. Figure 3 As shown, the protrusion direction of each strip protrusion 113 is opposite to that of a receiving cavity 130 along the stacking direction of a rectangular cover plate and a groove-shaped bottom shell 120.

[0079] like Figure 3 and Figure 4 As shown, two bending regions 114 are distributed on both sides of an annular protrusion 111. Each bending region 114 is inclined toward the end face 121 of a groove-shaped bottom shell 120. Each bending region 114 is used to bend at least one strip protrusion 113.

[0080] In this embodiment, the slotted bottom shell 120 and the rectangular cover plate 110 of the vehicle electrical device 100 are used to form a receiving cavity 130. The slotted bottom shell 120 is a bottom shell with a recessed shape 1111. It is understood that the shape of the rectangular cover plate 110 is not strictly rectangular; the rectangle primarily indicates that the rectangular cover plate 110 has both length and width directions.

[0081] In this embodiment, for ease of description, the stacking direction of the rectangular cover plate 110 and the grooved bottom shell 120 is denoted as the first direction A. Multiple fixing holes 112 are used to achieve a fixed connection between the rectangular cover plate 110 and the grooved bottom shell 120, wherein the fixing holes 112 of the rectangular cover plate 110 along the first direction A are opposite to the end face 121 of the grooved bottom shell 120. The multiple fixing holes 112 surround the annular protrusion 111, which helps to improve the connection strength between the rectangular cover plate 110 and the grooved bottom shell 120. In one embodiment, the distance between the fixing hole 112 along the first direction A and the electrical component 140 in the receiving cavity 130 is smaller than the distance between the annular protrusion 111 and the electrical component 140. It should be noted that... Figure 4The illustration only shows multiple fixing holes 112 surrounding the annular protrusion 111 and does not represent the specific arrangement or size of the fixing holes 112.

[0082] In this embodiment, the rectangular cover plate 110 is subjected to vibration from an excitation source. Resonance occurs when the natural vibration frequency of the rectangular cover plate 110 is close to the vibration frequency of the excitation source. Therefore, it is necessary to adjust the natural vibration frequency of the rectangular cover plate 110 to achieve frequency avoidance between the rectangular cover plate 110 and the excitation source. The natural vibration frequency is an inherent property of the vibration system and is related to the mass and stiffness of the system. The magnitude of the natural vibration frequency is proportional to the stiffness. According to the number of degrees of freedom of the system, resonance can be divided into different orders of resonance. The vibration frequency gradually increases from the first order to the higher orders, that is, the first order vibration frequency is the smallest among all orders of vibration frequency. Currently, the commonly used frequency avoidance method in the cover plate of the vehicle electrical device 100 is to increase the first order vibration frequency of the cover plate. However, with the continuous improvement and perfection of the structure, the space for increasing the first order vibration frequency is limited. It is difficult to further increase the first order vibration frequency of the cover plate on the existing basis. Moreover, it is difficult to achieve frequency avoidance between the cover plate and the motor shaft and reducer input shaft in the powertrain by increasing the first order vibration frequency.

[0083] To address the aforementioned issues, this embodiment of the application reduces the first-order vibration frequency of the rectangular cover plate 110 by using the annular protrusion 111 of the rectangular cover plate 110, thereby alleviating the first-order resonance problem of the rectangular cover plate 110.

[0084] In this embodiment, the annular protrusion 111 has an inner wall and an outer wall, and the inner wall of the annular protrusion 111 can form a cavity. Compared with the columnar design of the annular protrusion 111, this embodiment is advantageous in reducing the stiffness of the rectangular cover plate 110, thereby reducing the first-order vibration frequency of the rectangular cover plate 110, widening the gap between the first-order vibration frequency of the rectangular cover plate 110 and the vibration frequency of the excitation source, and reducing the number of times the rectangular cover plate 110 resonates.

[0085] In this embodiment, the annular protrusion 111 not only reduces the first-order vibration frequency but also reduces higher-order vibration frequencies, such as the fifth or sixth-order vibration frequencies. If the rectangular cover plate 110 only includes the annular protrusion 111, the reduced higher-order vibration frequencies will be difficult to avoid the excitation source. Specifically, in the rectangular cover plate 110, the region with the largest amplitude of higher-order vibration modes is concentrated at the edge of the rectangular cover plate 110.

[0086] To counteract the influence of the annular protrusion 111 on higher-order vibration frequencies, the rectangular cover plate 110 of this embodiment further includes multiple strip protrusions 113 and two bending regions 114. Both the strip protrusions 113 and the bending regions 114 can improve the stiffness of local areas of the rectangular cover plate 110. One end of each strip protrusion 113 is connected to the outer wall of the annular protrusion 111, and the other end of each strip protrusion 113 extends towards the periphery of the rectangular cover plate 110. The two bending regions 114 are arranged on both sides of the annular protrusion 111, with at least one strip protrusion 113 extending into one bending region 114. That is, both the strip protrusions 113 and the bending regions 114 are closer to the edge of the rectangular cover plate 110 than the annular protrusion 111, which helps maintain the higher-order vibration frequencies of the rectangular cover plate 110. It should be noted that... Figure 3 The diagram only schematically shows multiple strip protrusions 113 extending from the annular protrusion 111 to the edge of the rectangular cover plate 110, and does not represent the specific number or arrangement of the strip protrusions 113.

[0087] In this embodiment, the annular protrusion 111 is used to reduce the first-order vibration frequency of the rectangular cover plate 110. The strip protrusion 113 and the bent area 114 are arranged on the outer periphery of the annular protrusion 111. The strip protrusion 113 and the bent area 114 are used to increase the higher-order vibration frequency of the rectangular cover plate 110 to offset the effect of the annular protrusion 111 in reducing the higher-order vibration frequency. That is, in this embodiment, through the cooperation of the annular protrusion 111, the strip protrusion 113, and the bent area 114 of the rectangular cover plate 110, the difference between the first-order vibration frequency and the vibration frequency of the excitation source is widened without negatively affecting the higher-order vibration frequency, thereby improving the vibration reduction and noise reduction performance of the rectangular cover plate 110. In addition, this embodiment requires minimal structural modification to the rectangular cover plate 110, reducing the need for modifications to other structures of the vehicle electrical device 100 to accommodate the rectangular cover plate 110, which helps to reduce processing difficulty and cost.

[0088] In one embodiment, the rectangular cover plate 110 is a constrained damping structure. The rectangular cover plate 110 includes a base layer, a metal layer, and a damping layer located between the base layer and the metal layer. The distance between the base layer and the electrical component 140 along the first direction A is less than the distance between the constrained layer and the electrical component 140. The Young's modulus of the damping layer is less than the Young's modulus of either the base layer or the metal layer. Young's modulus refers to the ability to resist deformation.

[0089] In this embodiment, when the rectangular cover plate 110 is subjected to vibration, since the Young's modulus of both the base layer and the metal layer is greater than that of the damping layer, the base layer and the constraint layer can impede the tensile and bending deformation of the damping layer, causing shear deformation to occur inside the damping layer. Because shear deformation consumes more energy than tensile and bending deformation, the base layer and the constraint layer can improve the damping layer's energy dissipation effect. The rectangular cover plate 110 in this embodiment, being a constraint-damped structure, is beneficial for improving vibration reduction and noise reduction performance, and reducing the negative impact of vibration on the electrical components 140.

[0090] Please continue reading. Figure 4 In one embodiment, the ratio of the distance between the center of an annular protrusion 111 and the center of the rectangular cover 110 along the width direction B of the rectangular cover 110 to the width of the rectangular cover 110 is less than or equal to 1 / 5. Similarly, the ratio of the distance between the center of an annular protrusion 111 and the center of the rectangular cover 110 along the length direction D of the rectangular cover 110 to the length of the rectangular cover 110 is less than or equal to 1 / 4. The width of the rectangular cover 110 along its width direction is less than or equal to its length along its length direction. In one embodiment, the length direction D of the rectangular cover 110 is perpendicular to the width direction B of the rectangular cover 110.

[0091] In this embodiment, the cover plate of the vehicle electrical device 100 is typically a thin plate structure. The first-order vibration mode of a thin plate structure exhibits the characteristic of maximum amplitude at the center, with the amplitude decreasing radially from the center to the edge. The position of the annular protrusion 111 in the rectangular cover plate 110 affects the effect of the annular protrusion 111 in reducing the first-order vibration frequency. If the center of the annular protrusion 111 is far from the center of the rectangular cover plate 110, the amplitude of the area where the annular protrusion 111 is located is relatively smaller than the amplitude at the center of the rectangular cover plate 110, which is not conducive to the annular protrusion 111 playing a role in adjusting the vibration frequency of the rectangular cover plate 110.

[0092] In this embodiment, by adjusting the position of the annular protrusion 111 on the rectangular cover plate 110, the distance between the annular protrusion 111 and the center of the cover plate is shortened, thereby reducing the stiffness of the region with the largest amplitude in the rectangular cover plate 110. This effectively reduces the first-order vibration frequency of the rectangular cover plate 110, achieving frequency avoidance between the rectangular cover plate 110 and the excitation source, and alleviating the resonance problem. In one embodiment, the annular protrusion 111 is integrally die-cast into the rectangular cover plate 110. In this embodiment, the center of the annular protrusion 111 is close to the center of the rectangular cover plate 110, which also helps to reduce the difficulty and cost of die-casting the annular protrusion 111.

[0093] Please continue reading. Figure 4In one embodiment, the ratio of the inner diameter to the outer diameter of an annular protrusion 111 is greater than or equal to 5 / 6, and the ratio is less than or equal to 8 / 9. Along the width direction B of a rectangular cover plate 110, the ratio of the outer diameter of an annular protrusion 111 to the width of the rectangular cover plate 110 is greater than or equal to 1 / 3.

[0094] In this embodiment, a larger ratio of the inner diameter to the outer diameter of the annular protrusion 111 and a larger ratio of the outer diameter of the annular protrusion 111 to the width of the rectangular cover plate 110 will result in a larger volume of the inner void of the annular protrusion 111, making the effect of reducing the stiffness of the rectangular cover plate 110 more significant and thus improving the amplitude of the first-order vibration frequency change. Furthermore, a larger ratio of the inner diameter to the outer diameter of the annular protrusion 111 will also result in a smaller volume of the annular protrusion 111 itself, preventing an increase in the stiffness of the central region of the rectangular cover plate 110 due to an excessively large volume of the annular protrusion 111, and thus avoiding any negative impact on the effect of the annular protrusion 111 in reducing the first-order vibration frequency.

[0095] Please continue reading. Figure 4 In one embodiment, a plurality of strip protrusions 113 are spaced apart on the outer periphery of an annular protrusion 111 along the circumferential direction C of the annular protrusion 111, and the width of each strip protrusion 113 along the circumferential direction C of the annular protrusion 111 is greater than the difference between the outer diameter and the inner diameter of the annular protrusion 111.

[0096] In this embodiment, the strip protrusions 113 are used to counteract the influence of the annular protrusions 111 on the higher-order vibration frequencies of the rectangular cover plate 110. Multiple strip protrusions 113 are arranged at intervals along the circumferential direction C of the annular protrusions 111 on the outer periphery of the annular protrusions 111. The width of each strip protrusion 113 along the circumferential direction C of the annular protrusions 111 is greater than the difference between the inner and outer diameters of the annular protrusions 111. This expands the coverage area of ​​the multiple strip protrusions 113 on the rectangular cover plate 110 from both positional layout and circumferential dimension perspectives, which is beneficial for the strip protrusions 113 to maintain the higher-order vibration frequencies of the rectangular cover plate 110.

[0097] Please continue reading. Figure 4 In one embodiment, the minimum distance between each strip protrusion 113 and a fixing hole 112 is greater than or equal to the minimum distance between a bent region 114 and a fixing hole 112. The width of each strip protrusion 113 along the circumferential direction C of an annular protrusion 111 is greater than the minimum distance between a bent region 114 and a fixing hole 112.

[0098] In this embodiment, the strip protrusions 113 and the fixing holes 112 are arranged at intervals, and the strip protrusions 113 are far away from the fixing holes 112 relative to the bending area 114, so as to avoid the strip protrusions 113 interfering with the fixing effect of the fixing holes 112.

[0099] In this embodiment, the width of the strip protrusion 113 is compared with the minimum distance between the bending area 114 and the fixing hole 112. The relatively large width of the strip protrusion 113 can improve the stiffness of the area where the strip protrusion 113 is located, thereby increasing the higher-order vibration frequency. The relatively small minimum distance between the bending area 114 and the fixing hole 112 is beneficial to controlling the overall size of the rectangular cover plate 110, so as to realize the miniaturization design of the vehicle electrical device 100.

[0100] Please continue reading. Figure 3 In one embodiment, the ratio of the thickness of the outer wall of an annular protrusion 111 along the first direction A to the thickness of a rectangular cover plate 110 excluding the annular protrusion 111 and the plurality of strip protrusions 113 is less than or equal to 3 / 4.

[0101] In the embodiments of this application, such as Figure 3 As shown, the thickness of the outer wall of the annular protrusion 111 is denoted as T1, and the thickness of the rectangular cover plate 110 excluding the annular protrusion 111 and the strip protrusion 113 is denoted as T2. In this embodiment, by adjusting the ratio of T1 to T2 to be less than or equal to 3 / 4, it is beneficial to avoid the negative impact on the stiffness reduction effect of the annular protrusion 111 due to excessive outer wall thickness. It also allows for control of the overall thickness of the rectangular cover plate 110, which is beneficial for achieving miniaturized design of the vehicle electrical device 100.

[0102] Please continue reading. Figure 3 In one embodiment, the thickness of the outer wall of an annular protrusion 111 along the first direction A is greater than or equal to the thickness of each strip protrusion 113.

[0103] In this embodiment, the thickness of the outer wall of the annular protrusion 111 is compared with the thickness of each strip protrusion 113: the outer wall thickness of the annular protrusion 111 is relatively large, which is beneficial for the annular protrusion 111 to reduce the stiffness of the rectangular cover plate 110, thereby helping to widen the difference between the first-order vibration frequency of the rectangular cover plate 110 and the vibration frequency of the excitation source. One end of each strip protrusion 113 is connected to the outer wall of the annular protrusion 111, and the thickness of each strip protrusion 113 is relatively small, which is beneficial to improving the connection strength between each strip protrusion 113 and the annular protrusion 111, and also helps to reduce costs.

[0104] Please continue reading. Figure 3In one embodiment, the inner wall of an annular protrusion 111 is used to form a groove 1111 with a portion of a surface 115a of a rectangular cover plate 110. The portion of the surface 115a is located on the inner periphery of the annular protrusion 111. Along a first direction A, the portion of the surface 115a is recessed toward a receiving cavity 130. Along the first direction A, the groove depth of the groove 1111 is greater than the thickness of the outer wall of the annular protrusion 111.

[0105] In this embodiment of the application, for ease of description, the groove depth of the groove 1111 is denoted as T3. T3 is greater than T1, indicating that a portion of a surface 115a along the first direction A is recessed relative to the outer wall of the annular protrusion 111 toward the electrical component 140, which can achieve the frequency avoidance effect between the rectangular cover plate 110 and the excitation source by reducing the stiffness of the rectangular cover plate 110.

[0106] Please continue reading. Figure 3 In one embodiment, the ratio of the depth of the recess of a portion of a surface 115a along the first direction A to the thickness of a rectangular cover plate 110 excluding an annular protrusion 111 and a plurality of strip protrusions 113 is less than or equal to 1 / 4.

[0107] In this embodiment, the greater the depth of the groove 1111 formed by the inner wall of the annular protrusion 111 and a portion of a surface 115a, the lower the stiffness of the rectangular cover plate 110. However, the depth of the groove 1111 also needs to consider the damping performance of the rectangular cover plate 110 itself and the clearance between it and electrical components. Therefore, in this embodiment, the ratio of the recess depth of the portion of surface 115a used to form the groove 1111 to T2 is controlled to be less than or equal to 1 / 4. This helps to avoid negatively affecting the damping effect of the constraint damping structure in the rectangular cover plate 110, and also prevents the rectangular cover plate 110 from compressing the space in the receiving cavity 130 used to accommodate electrical components.

[0108] Please see Figure 5 , Figure 5 This is a cross-sectional view of the rectangular cover plate 110 provided in an embodiment of this application. For the sake of simplicity, Figure 5 Section lines are omitted. In one embodiment, the width of a portion of a surface 115a along the width direction B of a rectangular cover plate 110 is less than or equal to the inner diameter of an annular protrusion 111, and the length of a portion of a surface 115a along the length direction of a rectangular cover plate 110 is less than or equal to the inner diameter of an annular protrusion 111.

[0109] In this embodiment, a recessed portion with surface 115a facing the electrical component 140 can be spaced apart from the inner wall of the annular protrusion 111. Structurally, the width and length of the bottom of the groove 1111 are smaller than the inner diameter of the annular protrusion 111. This balances reducing the stiffness of the rectangular cover 110 with avoiding affecting its damping performance and meeting the requirement of the rectangular cover 110 avoiding the electrical component, thus improving the practicality of the rectangular cover 110. In one embodiment, the inner wall of the annular protrusion 111 and the bottom of the groove 1111 are formed independently. For example, the inner wall of the annular protrusion 111 and the recessed portion with surface 115a facing the electrical component are respectively processed and formed, and then the annular protrusion 111 is fixed to the outer periphery of the recessed portion with surface 115a facing the electrical component by welding, gluing, screw connection, or other methods. In one embodiment, the inner wall of the annular protrusion 111 and the bottom of the groove 1111 can be integrally formed, such that the width and length of the bottom of the groove 1111 are equal to the inner diameter of the annular protrusion 111.

[0110] Please continue reading. Figure 3 In one embodiment, along a first direction A, another surface 115b of a rectangular cover plate 110 is opposite to a surface 115a. A portion of the other surface 115b is aligned with a portion of the surface 115a along the first direction A, and the portion of the other surface 115b protrudes along the first direction A toward the electrical component 140. The protrusion height of the portion of the other surface 115b is equal to the recess depth of the portion of the surface 115a.

[0111] In this embodiment of the application, a portion of surface 115a and a portion of surface 115b of the rectangular cover plate 110 are die-cast, such that a portion of surface 115a is recessed toward the electrical component 140 and a portion of surface 115b is protruded toward the electrical component 140, which helps to reduce the stiffness of the center of the rectangular cover plate 110 and reduce the first-order vibration frequency of the center of the rectangular cover plate 110.

[0112] Please continue reading. Figure 3 In one embodiment, the minimum included angle between each bending region 114 and the end face 121 of a grooved bottom shell 120 is greater than or equal to 10 degrees, and the minimum included angle between each bending region 114 and the end face 121 of a grooved bottom shell 120 is less than or equal to 45 degrees.

[0113] In this embodiment, the angle α between the bending region 114 and the end face 121 of the grooved bottom shell 120 has a significant impact on maintaining higher-order vibration frequencies. If the angle between the bending region 114 and the end face 121 of the grooved bottom shell 120 is too small, the bending region 114 and the end face 121 of the grooved bottom shell 120 will be approximately coplanar, making it difficult for the bending region 114 to improve the local stiffness of the rectangular cover plate 110, resulting in a negligible increase in higher-order vibration frequencies. If the angle between the bending region 114 and the end face 121 of the grooved bottom shell 120 is too large, it will affect the overall thickness of the rectangular cover plate 110, causing an excessive reduction in the first-order vibration frequency. Furthermore, the structure of the grooved bottom shell 120 needs to be adjusted to match the rectangular cover plate 110, resulting in high costs. This embodiment of the application, by adjusting the angle α between the bending region 114 and the end face 121 of the grooved bottom shell 120 to a range of 10 degrees to 45 degrees, helps to alleviate the above problems.

[0114] Please continue reading. Figure 4 In one embodiment, two bending regions 114 are distributed on both sides of an annular protrusion 111 along the length direction D of a rectangular cover plate 110. The length of each bending region 114 along the length direction D of the rectangular cover plate 110 is greater than the outer diameter of the annular protrusion 111, and the length of each bending region 114 along the length direction D of the rectangular cover plate 110 is less than the maximum distance between the centers of the two fixing holes 112.

[0115] In this embodiment, the bending region 114 increases the local stiffness of the rectangular cover plate 110 where the bending region 114 is located, thereby offsetting the effect of the annular protrusion 111 in reducing higher-order vibration frequencies. For ease of description, the two bending regions 114 arranged along the length D of the rectangular cover plate 110 on both sides of the annular protrusion 111 are referred to as bending regions 114a. The length of the bending region 114a is greater than the outer diameter of the annular protrusion 111, which helps to ensure that the bending region 114a plays its role in increasing higher-order vibration frequencies. Figure 4 As shown, the length of the bending area 114a is less than the maximum distance L1 between the two fixing holes 112 along the length direction D of the rectangular cover plate 110, which can avoid the bending area 114a from having a negative impact on the connection stability between the rectangular cover plate 110 and the groove bottom shell 120.

[0116] Please see Figure 6 , Figure 6This is another top view of the rectangular cover plate 110 provided in an embodiment of this application. In one embodiment, the rectangular cover plate 110 further includes two additional bending regions 114, which are distributed on both sides of an annular protrusion 111 along the width direction B of the rectangular cover plate 110. The width of each of the two bending regions 114 along the width direction B of the rectangular cover plate 110 is greater than the outer diameter of the annular protrusion 111, and the width of each of the two bending regions 114 along the width direction B of the rectangular cover plate 110 is less than the maximum distance between the centers of the two fixing holes 112.

[0117] In this embodiment, four bending regions 114 are arranged on different sides of the annular protrusion 111, which helps to enhance the effect of the bending regions 114 in raising the higher-order vibration frequency, expand the range of local stiffness improvement in the rectangular cover plate 110, and avoid the higher-order vibration frequency of the rectangular cover plate 110 from the vibration frequency of the excitation source, thereby alleviating the problem of resonance of the rectangular cover plate 110.

[0118] In this embodiment, for ease of description, the two additional bending regions 114 arranged along the width direction B of the rectangular cover plate 110 on both sides of the annular protrusion 111 are referred to as bending regions 114b. The width of the bending regions 114b is greater than the outer diameter of the annular protrusion 111, which helps to ensure that the bending regions 114b play a role in enhancing higher-order vibration frequencies. Figure 6 As shown, the width of the bending region 114b is less than the maximum spacing W1 of the two fixing holes 112 along the width direction B of the rectangular cover plate 110, which can avoid the bending region 114b negatively affecting the connection stability between the rectangular cover plate 110 and the channel-shaped bottom shell 120. It is understandable that the length of the bending region 114a and the width of the bending region 114b also need to consider the avoidance of misalignment with other structures of the rectangular cover plate 110. That is, in practice, the ratio of the length of the bending region 114a to the length of the rectangular cover plate 110 and the ratio of the width of the bending region 114b to the width of the rectangular cover plate 110 can both be less than [a certain value]. Figure 4 and Figure 6 The situation shown in the figure.

[0119] The foregoing has provided a detailed description of the vehicle-mounted electrical device, powertrain, and vehicle provided in the embodiments of this application. Specific examples have been used to illustrate the principles and embodiments of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in specific embodiments and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A vehicle-mounted electrical device, characterized in that: The housing of the vehicle-mounted electrical device comprises a groove-shaped bottom shell and a rectangular cover plate, wherein the rectangular cover plate is used to be stacked on the groove-shaped bottom shell to form a receiving cavity, wherein the receiving cavity is used to receive a plurality of electrical components of the vehicle-mounted electrical device, and the rectangular cover plate comprises: an annular protrusion, wherein the protrusion direction of the annular protrusion is away from the one accommodating cavity along the stacking direction of the one rectangular cover plate and the one groove-shaped bottom shell; A plurality of fixing holes, the plurality of fixing holes surround the one annular protrusion, each of the fixing holes penetrates the one rectangular cover plate along the stacking direction of the one rectangular cover plate and the one groove-shaped bottom shell, each of the fixing holes is used to pass through a fixing member, and each of the fixing members is used to fix and connect the end surface of the one groove-shaped bottom shell facing the one rectangular cover plate; A plurality of strip-shaped protrusions, each of which extends from the outer periphery of the annular protrusion toward the periphery of the rectangular cover plate, and the protrusion direction of each of the strip-shaped protrusions is away from the accommodating cavity along the stacking direction of the rectangular cover plate and the groove-shaped bottom shell; Two bending areas, the two bending areas are distributed on both sides of the one annular protrusion, each of the bending areas is inclined toward the end surface of the one groove-shaped bottom shell, and each of the bending areas is used to bend at least one of the strip-shaped protrusions.

2. The vehicle-mounted electrical device according to claim 1, characterized in that: The ratio of the distance between the center of the annular protrusion and the center of the rectangular cover plate along the width direction of the rectangular cover plate to the width of the rectangular cover plate is less than or equal to 1 / 5, and the ratio of the distance between the center of the annular protrusion and the center of the rectangular cover plate along the length direction of the rectangular cover plate to the length of the rectangular cover plate is less than or equal to 1 / 4.

3. The vehicle-mounted electrical device according to claim 1, characterized in that: The ratio of the inner diameter of the one annular protrusion to the outer diameter of the one annular protrusion is greater than or equal to 5 / 6, and the ratio of the inner diameter of the one annular protrusion to the outer diameter of the one annular protrusion is less than or equal to 8 / 9; A ratio of an outer diameter of the annular protrusion to a width of the rectangular cover plate along a width direction of the rectangular cover plate is greater than or equal to 1 / 3.

4. The vehicle-mounted electrical device according to claim 3, characterized in that: The plurality of strip protrusions are arranged at intervals on the outer peripheral side of the annular protrusion along the circumference of the annular protrusion, and the width of each strip protrusion along the circumference of the annular protrusion is greater than the difference between the outer diameter of the annular protrusion and the inner diameter of the annular protrusion.

5. The vehicle-mounted electrical device according to claim 4, characterized in that: The minimum distance between each of the strip-shaped protrusions and one of the fixing holes is greater than or equal to the minimum distance between one of the bending areas and one of the fixing holes; The width of each of the strip-shaped protrusions along the circumference of the annular protrusion is greater than the minimum distance between one of the bending areas and one of the fixing holes.

6. The vehicle-mounted electrical device according to claim 1, characterized in that: The ratio of the thickness of the outer wall of the annular protrusion along the stacking direction of the rectangular cover plate and the groove-shaped bottom shell to the thickness of the rectangular cover plate excluding the annular protrusion and the plurality of strip-shaped protrusions is less than or equal to 3 / 4.

7. The vehicle-mounted electrical device according to claim 6, characterized in that: The thickness of the outer wall of the annular protrusion along the stacking direction of the rectangular cover plate and the groove-shaped bottom shell is greater than or equal to the thickness of each of the strip-shaped protrusions.

8. The vehicle-mounted electrical device according to claim 6, characterized in that: The inner wall of the annular protrusion is used to form a groove with a portion of a surface of the rectangular cover plate, the portion of the surface is located on the inner circumference of the annular protrusion, and along the stacking direction of the rectangular cover plate and the groove-shaped bottom shell, the portion of the surface is recessed toward the accommodating cavity, and along the stacking direction of the rectangular cover plate and the groove-shaped bottom shell, the depth of the groove is greater than the thickness of the outer wall of the annular protrusion.

9. The vehicle-mounted electrical device according to claim 8, characterized in that: The ratio of the depression depth of the portion of the one surface along the stacking direction of the one rectangular cover plate and the one groove-shaped bottom shell to the thickness of the one rectangular cover plate excluding the one annular protrusion and the multiple strip-shaped protrusions is less than or equal to 1 / 4.

10. The vehicle-mounted electrical device according to claim 8, characterized in that: The width of the portion of the surface along the width direction of the rectangular cover plate is less than or equal to the inner diameter of the annular protrusion, and the length of the portion of the surface along the length direction of the rectangular cover plate is less than or equal to the inner diameter of the annular protrusion.

11. The vehicle-mounted electrical device according to any one of claims 1 to 10, characterized in that: The minimum angle between each of the bending regions and the end surface of the groove-shaped bottom shell is greater than or equal to 10 degrees, and the minimum angle between each of the bending regions and the end surface of the groove-shaped bottom shell is less than or equal to 45 degrees.

12. The vehicle-mounted electrical device according to claim 11, characterized in that: The two bending areas are distributed on both sides of the annular protrusion along the length direction of the rectangular cover plate, the length of each of the two bending areas along the length direction of the rectangular cover plate is greater than the outer diameter of the annular protrusion, and the length of each of the two bending areas along the length direction of the rectangular cover plate is less than the maximum distance between the centers of the two fixing holes.

13. The vehicle-mounted electrical device according to claim 12, characterized in that: The rectangular cover plate also includes two other bending areas, which are distributed on both sides of the annular protrusion along the width direction of the rectangular cover plate. The width of each of the other two bending areas along the width direction of the rectangular cover plate is greater than the outer diameter of the annular protrusion, and the width of each of the other two bending areas along the width direction of the rectangular cover plate is less than the maximum distance between the centers of the two fixing holes.

14. A powertrain, characterized in that: The powertrain includes a motor, a reducer and an on-board electrical device as described in any one of claims 1 to 13, wherein the on-board electrical device is used to transmit electrical energy to the motor through the multiple electrical components, and the motor is used to convert the electrical energy into mechanical energy and transmit the mechanical energy to the reducer.

15. A vehicle, characterized in that: The vehicle includes a frame, a battery pack and a powertrain as described in claim 14, wherein the frame is used to fix the battery pack and the powertrain, the battery pack is used to provide electrical energy to the motor in the powertrain through the on-board electrical device, and the powertrain is used to drive the wheels of the vehicle.

Images