High-strength die-casting new energy automobile steering gear shell

Abstract

The invention discloses a high-strength die-casting new energy automobile steering gear shell. The high-strength die-casting new energy automobile steering gear shell comprises a main shell, a shaft end cover, an inner shaft barrel, a damping interlayer structure, an acoustic cavity structure and a micro-ripple structure. The main shell is formed by integral die-casting, and a plurality of groups of micro-ripple structures distributed along the circumferential direction are arranged on the peripheral surface of the main shell so as to form a periodic rigidity change area; a damping interlayer structure is constructed between the inner wall of the main shell and the outer wall of the inner shaft barrel, and absorption of low-frequency vibration energy is achieved through the double-face attaching effect of an elastic interlayer material. An acoustic cavity structure is further formed on the inner side of the main shell, and a silencing grid is arranged in the cavity and used for scattering and phase interference of intermediate-frequency noise such as rack meshing. Through cooperative arrangement of the inner damping layer, the middle acoustic cavity layer and the outer micro-ripples layer, graded attenuation paths can be formed for low-frequency, medium-frequency and high-frequency vibration noise, the overall NVH performance and structural stability of the steering gear shell are remarkably improved, and the requirements of modern vehicles for driving quietness and control quality are met.

Description

Technical Field

[0001] This invention relates to the field of automotive steering technology, specifically a high-strength die-cast steering gear housing for new energy vehicles. Background Technology

[0002] As a core component of the vehicle steering system, the automotive steering gear's housing structure is typically formed using casting or die casting processes. It bears the working loads of the rack, gears, bearings, and power steering mechanism, and transmits road impacts and vibrations from the powertrain. In existing technologies, traditional steering gear housings mostly employ a single-piece metal structure, and their NVH (noise, vibration, and harshness) performance primarily relies on the housing wall thickness, local reinforcing ribs, and the material's inherent stiffness. However, with the increasing demands for vehicle driving comfort and quietness, simply increasing the housing stiffness or wall thickness is no longer sufficient to meet noise control requirements.

[0003] Typical structural optimization methods in existing technologies include: adding reinforcing ribs on the outside of the shell to improve local stiffness, or using local damping pads to reduce vibration in specific frequency bands. However, such structures are often only effective for a single vibration frequency band and lack comprehensive control over low-frequency structural vibration, mid-frequency gear meshing noise, and high-frequency howling noise. Furthermore, traditional reinforcing rib structures are difficult to actively reduce the sound energy transmitted to the inside of the shell, and their effect on weakening resonant sound waves in the rack meshing area is limited. In addition, the conventional planar structure of the outer surface of the shell easily allows high-frequency structural waves to propagate rapidly, creating a diffusion path for high-frequency noise on the shell surface, resulting in noticeable howling noise in the vehicle under certain operating conditions.

[0004] Furthermore, existing steering gear housings generally lack internal acoustic structures, making it impossible to classify and process noise of different frequency bands through cavity tuning. They also lack sandwich damping structures for low-frequency vibrations, resulting in a large overall amplitude structural response when subjected to road impacts or changes in power steering system load. In addition, the continuous and uniform stiffness distribution of the single-layer metal material in existing housing structures makes it difficult to create a blocking or scattering effect on high-frequency structural waves, significantly limiting their effectiveness in NVH optimization.

[0005] Therefore, existing steering gear housings still have shortcomings in overall vibration control, graded noise attenuation, structural stability, and comprehensive NVH performance across frequency bands, making it difficult to meet the requirements of next-generation vehicles for driving quietness and handling stability. This invention addresses these technical problems by constructing a damping interlayer, an acoustic cavity silencing structure, and an outer microwave-textured composite structure to achieve graded absorption and attenuation of low-frequency, mid-frequency, and high-frequency vibration noise, thereby significantly improving the NVH performance and durability of the steering gear housing. Summary of the Invention

[0006] This invention aims to solve the problems of insufficient low-frequency vibration attenuation capability, ineffective modulation of mid-frequency meshing noise, and rapid propagation of high-frequency structural waves along the shell in existing steering gear housings. This invention proposes a die-cast automotive steering gear housing structure with multi-level NVH optimization capability. Through the comprehensive configuration of inner layer damping, middle layer acoustic cavity and outer layer microwave texture structure, it achieves synergistic attenuation of different vibration and noise sources from low frequency to mid frequency to high frequency, thereby significantly improving the vehicle's handling stability and driving quietness.

[0007] The overall design of this invention employs a multi-level structural layout comprising a main housing, shaft end caps, an inner shaft cylinder, a damping interlayer structure, an acoustic cavity structure, and a microwave ripple structure. This enables the steering gear housing to possess combined functions of material damping, acoustic modulation, and surface structural wave scattering. Specifically, the damping interlayer structure is located inside the main housing and is used to absorb low-frequency structural vibrations; the acoustic cavity structure is formed on the inner wall of the housing for mid-frequency sound wave scattering and tuning; and the microwave ripple structure is arranged on the outer surface of the housing to disrupt the continuous propagation path of high-frequency structural waves. Through this combined design, the steering gear housing constructed by this invention possesses targeted processing capabilities across different vibration frequency bands, resulting in overall NVH performance significantly superior to existing technologies.

[0008] This invention provides a die-cast steering gear housing structure, including a main housing, a shaft end cap, an inner shaft cylinder, a damping interlayer structure, an acoustic cavity structure, and a microwave-patterned structure. The main housing is integrally die-cast, and its outer circumferential surface features multiple circumferentially extending microwave-patterned structures, forming continuous peaks and troughs internally, giving the outer surface of the housing a periodic bending stiffness variation zone. An interlayer space is formed between the inner side of the main housing and the outer side of the inner shaft cylinder, within which a damping interlayer structure is arranged in a continuous circumferential pattern to absorb energy during low-frequency vibration input. The inner wall of the main housing forms an acoustic cavity structure, within which a sound-absorbing grid is arranged to scatter, reflect, and cause phase interference of mid-frequency resonant waves.

[0009] Specifically, during the transmission of vibrations at low, medium, and high frequencies, the vibration energy is weakened in stages at the damping sandwich structure, acoustic cavity structure, and microwave ripple structure, respectively, thus achieving cross-frequency composite NVH control.

[0010] In a preferred example, the damping sandwich structure comprises an annular groove segment formed on the inner wall of the main shell and an elastic sandwich body disposed within the groove segment. A circumferentially extending limiting rib is provided on the inner side of the groove segment, effectively constraining the elastic sandwich body in both the axial and radial directions. The outer surface of the elastic sandwich is connected to the inner wall of the main shell by mechanical fastening or micro-protrusion embedding, while the inner surface is attached to the outer wall of the inner shaft cylinder, thus forming a double-sided attached sandwich damping structure.

[0011] Specifically, the damping sandwich structure can exhibit internal friction behavior under low-frequency vibration, thereby absorbing the impact force of the road surface and the low-frequency dynamic load of the assist system, and significantly reducing the overall vibration response of the main shell.

[0012] In a preferred example, the connection between the shaft end cap and the main housing is provided with multiple axially extending reinforcing ribs, and the cross-section of the reinforcing ribs is trapezoidal or arc-trapezoidal, forming a high-rigidity support band in the end region. The micro-wave textured structure is spatially staggered with the reinforcing ribs, so that the two types of structures provide circumferential and axial reinforcement paths respectively.

[0013] Specifically, the reinforcing ribs and the microwave textured structure work together to improve the load-bearing capacity and vibration stability of the shaft end area, making the stress distribution of the shell more uniform when subjected to torque or impact loads.

[0014] In a preferred example, the acoustic cavity structure consists of an inner arc wall, an outer arc wall, and sealing ribs, forming a multi-segment annular structure. Different cavity segments are separated from each other by partition ribs, thus constituting multiple independent or interconnected acoustic units. The anechoic grid includes a first rib extending radially and a second rib extending circumferentially, which, when combined, form a grid-like acoustic modulation structure.

[0015] Specifically, the acoustic cavity structure and the noise-absorbing grid can scatter, reflect, and phase-interfere rack meshing noise, rotational unevenness noise, and mid-frequency structural sound waves, forming a mid-frequency sound-absorbing band, thereby reducing the structural resonance effect.

[0016] In a preferred example, the microwave textured structure consists of multiple radial peaks and troughs, with the peaks extending along the axial direction of the shell and the peak heights gradually varying, giving the outer surface of the shell different bending stiffnesses at different angular positions.

[0017] Specifically, the microwave ripple structure can disrupt the continuous propagation path of high-frequency structural waves, causing high-frequency howling noise to be scattered or dissipated on the surface, thereby significantly improving high-frequency NVH performance.

[0018] In a preferred example, the damping interlayer structure, the acoustic cavity structure, and the microwave ripple structure are arranged sequentially along the radial direction of the shell, so that vibrations of different frequency bands are treated at different structural levels. The damping interlayer absorbs low-frequency acoustic energy, the acoustic cavity modulates mid-frequency resonance with the silencer, and high-frequency structural waves are scattered, reflected, or dissipated at the microwave ripple structure.

[0019] Specifically, this invention achieves continuous NVH control across frequency bands, enabling the steering gear housing to have stable vibration suppression performance under various operating conditions, which is significantly better than traditional single-layer structure housings.

[0020] The beneficial effects achieved by this invention are as follows: 1. In this invention, by setting a damping sandwich structure in the main housing, the steering gear can absorb energy under the internal friction of the sandwich material when subjected to low-frequency vibrations from road impacts, rack engagement, and power assist mechanism, which greatly reduces the overall vibration response of the housing and improves structural stability and durability.

[0021] 2. In this invention, by forming an acoustic cavity structure and arranging a noise-absorbing grid inside the main housing, the mid-frequency gear meshing noise, rotational unevenness noise, and structural resonance noise are scattered, reflected, and phase-interfered inside the cavity, achieving graded attenuation and significantly improving the NVH performance of the steering gear during driving.

[0022] 3. In this invention, by arranging a microwave textured structure on the outside of the main housing, the high-frequency structural wave is scattered and dissipated during the periodic stiffness change of the wave crest and trough, effectively suppressing high-frequency noise such as howling. At the same time, combined with the axle end cover reinforcement structure to improve the force path, a multi-level comprehensive noise reduction effect is formed that runs through low frequency, mid frequency and high frequency, so that the overall steering gear housing has better NVH performance and service life. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present invention; Figure 2 This is a schematic diagram of the surface structure of the shaft end cap according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the inner structure of the main housing according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a microwave textured structure according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the acoustic cavity structure and its inner silencing grid structure according to an embodiment of the present invention.

[0024] Figure label: 100. Main housing; 110. Shaft end cap; 120. Damping sandwich structure; 130. Reinforcing rib; 200. Inner shaft cylinder; 300. Acoustic cavity structure; 310. Noise-canceling grid; 400. Microwave texture structure. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0026] It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the invention.

[0027] The following describes, with reference to the accompanying drawings, some embodiments of the present invention, providing a high-strength die-cast steering gear housing for new energy vehicles.

[0028] Combination Figures 1-5 As shown, the present invention provides a high-strength die-cast steering gear housing for new energy vehicles, comprising a main housing 100, a shaft end cover 110, an inner shaft cylinder 200, a damping interlayer structure 120, an acoustic cavity structure 300, and a microwave textured structure 400.

[0029] The main shell 100 is integrally die-cast, and its outer circumferential surface is distributed with multiple microwave texture structures 400. Each microwave texture structure 400 is composed of radial peaks and valleys, and the peaks extend along the axial direction of the shell, so that the outer side of the main shell 100 forms a periodic bending stiffness variation region, thereby providing attenuation capability for the propagation of vibration on the outside.

[0030] An annular interlayer space is formed between the inner wall of the main shell 100 and the outer wall of the inner shaft cylinder 200. A damping interlayer structure 120 is provided in the annular interlayer space. The structure is continuously arranged along the circumference of the shell to form a composite interlayer damping layer between the main shell 100 and the inner shaft cylinder 200, which is used to absorb the structural vibration energy of the shell.

[0031] An acoustic cavity structure 300 is further formed on the inner wall of the main housing 100. This structure is arranged in a ring or multi-segment arc around the inner shaft cylinder 200. Multiple noise-absorbing grids 310 are set inside the structure. The noise-absorbing grids 310 are composed of radial ribs and circumferential segmented pieces, so that the acoustic cavity structure 300 has multiple sound wave scattering paths, thereby achieving structural reduction of mid-to-high frequency noise.

[0032] The three types of structures (damping interlayer structure 120, acoustic cavity structure 300, and microwave texture structure 400) are arranged in sequence from the inside to the outside along the radial direction of the shell to form a multi-level vibration attenuation system, thereby achieving synergistic suppression of low-frequency modes, mid-frequency resonances, and high-frequency howling.

[0033] like Figure 2 and Figure 3 As shown, the inner surface of the main housing 100 is provided with a circumferential groove segment, which is continuously arranged along the circumference of the housing. Its inner surface has a number of circumferentially extending limiting rib protrusions, which are used to constrain the damping interlayer structure 120 in the radial direction.

[0034] The damping sandwich structure 120 includes a preset elastic sandwich body, the outer side of which contacts the inner wall of the groove of the main housing 100 by mechanical embedding or micro-protrusion embedding, and the inner side of which is attached to the outer wall of the inner shaft cylinder 200, so that the damping sandwich structure 120 forms a double-sided attachment structure with outer and inner attachment.

[0035] like Figure 3As shown, the annular interlayer space formed between the inner cylinder 200 and the main shell 100 has a radially periodically varying structure, that is, the radial space width is different at different angular positions, so that the damping interlayer structure 120 has a gradually varying thickness in the circumferential direction, thereby achieving differentiated damping response and enhancing the absorption effect of the shell on rotational unbalance excitation.

[0036] When the vehicle is in motion, the impact force from the road surface, the meshing force of the steering rack, and the low-frequency structural vibrations generated by the power steering system are transmitted to the main housing 100. These vibrations typically have a large amplitude and a low frequency.

[0037] like Figure 2 and Figure 3 As shown, the damping interlayer structure 120, which is disposed between the inner side of the main shell 100 and the outer wall of the inner shaft cylinder 200, is arranged in a continuous ring. Under the action of vibration load, the elastic interlayer body will undergo slight deformation. Since its two sides are attached to the main shell 100 and the inner shaft cylinder 200 respectively, the vibration energy needs to be dissipated through the damping material.

[0038] The gradually varying thickness and limiting ribs of the damping sandwich structure 120 provide differentiated damping resistance in the circumferential direction, which disperses the radial vibration energy of the shell and partially converts it into material internal friction, thereby reducing the overall vibration amplitude of the main shell 100.

[0039] Therefore, this structure is mainly designed to effectively attenuate the structural vibrations generated by the steering gear in the low-frequency range (such as 10Hz-200Hz).

[0040] like Figure 1 and Figure 4 As shown, the shaft end cap 110 is connected to the main housing 100 by screwing or press-fitting, and multiple reinforcing ribs 130 are arranged along the axial direction in the connection area between the shaft end cap 110 and the main housing 100.

[0041] The reinforcing rib 130 has a trapezoidal or arc-trapezoidal cross section and is integrally die-cast with the shaft end cap 110 and the main housing 100, forming a local stiffness enhancement zone in the end cap area, thereby improving the torsional resistance of the end cap area.

[0042] like Figure 4 As shown, the microwave textured structure 400 is arranged along the outer periphery of the main shell 100. Its position and some of the reinforcing ribs 130 are spatially intersected, so that the circumferential reinforcement effect provided by the microwave textured structure 400 and the axial reinforcement effect provided by the reinforcing ribs 130 form a composite reinforcement network, which is beneficial to the multi-path diversion of load in the junction area between the shell and the end cover.

[0043] like Figure 3 and Figure 5As shown, the acoustic cavity structure 300 is located on the inner wall of the main shell 100 and is composed of an inner arc wall, an outer arc wall and closed ribs at both ends, forming an overall three-dimensional annular cavity.

[0044] The acoustic cavity structure 300 can be composed of multiple segmented cavities, with adjacent cavity segments isolated by spacer ribs, so that multiple independent resonant cavities can be formed, thereby tuning for different noise frequency bands.

[0045] like Figure 5 As shown, the noise-absorbing grid 310 is disposed inside the acoustic cavity structure 300, including multiple first ribs extending radially and multiple second ribs extending circumferentially, which together constitute a multi-grid structure.

[0046] in: The two ends of the first rib are fixed between the inner and outer arc walls of the acoustic cavity structure 300, respectively. The second rib is located between the adjacent first rib, so that the acoustic cavity structure 300 is divided into several open rectangular or arc grids.

[0047] The grid size, proportion, and orientation of the noise-canceling grid 310 correspond to the wavelength of the sound wave, which can cause the sound wave to scatter, refract, and locally reflect inside the cavity, thereby improving the structure's ability to suppress mid-to-high frequency noise.

[0048] In vehicle steering systems, mid-frequency noise mainly originates from rack-and-pinion meshing, uneven bearing rotation, and power steering system vibration. These noise frequencies are typically between 200Hz and 1500Hz and possess a certain energy density.

[0049] like Figure 3 and Figure 5 As shown, an acoustic cavity structure 300 is provided on the inner wall of the main housing 100. This structure is a three-dimensional arc-shaped cavity formed by an inner arc wall, an outer arc wall, and end sealing ribs. After the sound wave enters this region, the curved surface structure of the cavity will cause the sound wave path to deflect, and the grid structure formed by the silencing grid 310 will further divide the sound wave into multiple propagation paths of different scales.

[0050] The staggered arrangement of radial and circumferential ribs causes sound waves to scatter, reflect, partially reflect, and be subject to phase interference within the cavity, thereby disrupting the continuous propagation path of mid-frequency sound waves and causing energy splitting and attenuation.

[0051] Multi-segment acoustic cavity unit design ( Figure 5 (As shown) This invention further enables sound waves of different frequencies to be absorbed in different cavity segments, giving it a significant advantage in suppressing mid-frequency structural noise.

[0052] like Figure 5Further, it is shown that the acoustic cavity structure 300 and the damping interlayer structure 120 are radially distributed in adjacent positions, and together with the outer microwave texture structure 400, they form a multi-level attenuation path to weaken structural vibrations in different frequency bands.

[0053] like Figure 1 and Figure 4 As shown, the microwave textured structure 400 is continuously arranged along the outer periphery of the main shell 100. Each microwave textured structure 400 is composed of a wave-shaped rib with crests and troughs. The crests extend along the axial direction of the shell, and their radial height is gradually distributed, so that the outer wall of the shell has asymmetrical bending stiffness at different angular positions.

[0054] High-frequency noise (above 1500Hz) is usually caused by excitation from metallic howling, tooth surface impact, high-frequency harmonics of the boost motor, etc. Its energy propagation speed is fast, the structural wave wavelength is short, and it is easy to propagate through the shell surface.

[0055] When a high-frequency vibration wave propagates along the outer wall of the shell, it encounters a structure with alternating crests and troughs, causing the instantaneous propagation path to bend. The sudden change in local bending stiffness prevents the continuous transfer of energy, resulting in reflection, scattering, and small-scale dissipation.

[0056] The gradually varying height design of the microwave textured structure 400 causes vibrations to encounter different impedances at different angular positions, resulting in multiple scattering and interference of high-frequency sound waves, further reducing their efficiency in propagating along the shell.

[0057] The waveform arrangement of this microwave textured structure 400 creates a periodic stiffness distribution on the surface of the main shell 100, which can generate a direction-dependent bending response when the shell is under load. This causes the vibration energy propagating to the outer wall of the main shell 100 to be locally dissipated at the microwave textured structure, thereby effectively reducing the vibration transmission efficiency.

[0058] like Figures 1 to 5 In summary, the damping sandwich structure 120 of this invention is located in the innermost layer, the acoustic cavity structure 300 is located in the middle layer, and the microwave ripple structure 400 is located in the outermost layer. The three are distributed in radial order to form a complete multi-level NVH optimization system. The damping sandwich structure 120 is mainly responsible for weakening low-frequency structural vibrations; The acoustic cavity structure 300, in conjunction with the noise-canceling grid 310, is used to adjust and reduce mid-frequency resonance noise; The microwave textured structure 400 is used to reduce high-frequency whistling and vibration of the shell surface.

[0059] Through the coordinated arrangement of multiple structures, a composite noise reduction and vibration absorption effect across frequency bands and multiple modes is achieved.

[0060] Working principle and usage process of this invention: The main housing 100 is equipped with a multi-level vibration and noise attenuation system consisting of a damping interlayer structure 120, an acoustic cavity structure 300, and a microwave ripple structure 400 arranged sequentially from the inside out. When the low-frequency, mid-frequency, and high-frequency vibrations generated by the vehicle during driving and turning are transmitted to the main housing 100 in sequence, the damping interlayer structure 120 first absorbs the low-frequency structural vibration energy by using its double-sided attached elastic damping material and converts it into material internal loss. Then, it enters the acoustic cavity structure 300, where sound wave scattering, reflection, and phase interference occur in the grid-like arc-shaped cavity composed of the inner arc wall, outer arc wall, and silencing grid 310, thereby attenuating the mid-frequency resonant noise. Finally, the high-frequency structural waves transmitted to the outer surface of the main housing 100 are scattered, reflected, and locally dissipated in the periodic stiffness variation area formed by the microwave ripple structure 400, causing the high-frequency howling noise to attenuate rapidly. Meanwhile, the composite reinforcement path formed by the reinforcing rib 130 and the microwave textured structure 400 at the shaft end cover 110 further improves the stress and vibration distribution of the housing, enabling the present invention to achieve continuous NVH optimization effect from low frequency to high frequency, and significantly improve the noise reduction performance and structural stability of the steering gear housing.

[0061] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0062] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high-strength die-cast steering gear housing for new energy vehicles, characterized in that, It includes a main housing (100), a shaft end cap (110), an inner shaft cylinder (200), a damping interlayer structure (120) disposed between the main housing (100) and the inner shaft cylinder (200), and an acoustic cavity structure (300) formed inside the main housing (100). The main shell (100) is integrally die-cast and its outer circumferential surface is provided with a microwave textured structure (400) continuously arranged along the circumference of the shell. The microwave textured structure (400) is composed of multiple corrugated ribs that form alternating peaks and troughs in the radial direction, and each corrugated rib has a ridge-shaped profile that extends along the axial direction of the shell, so that the outer surface layer of the main shell (100) forms a periodic bending stiffness variation zone. The damping interlayer structure (120) is formed in the annular interlayer space between the inner wall of the main shell (100) and the outer wall of the inner shaft cylinder (200). The annular interlayer space is continuously arranged along the circumference of the shell, and its cross-section has a gradually changing thickness structure. The inner surface and the outer surface have limiting steps, so that the damping interlayer structure (120) is constrained in the circumferential direction and forms a composite layered structure with the main shell (100). The acoustic cavity structure (300) is an annular arc-shaped cavity formed along the inner side of the main shell (100). Multiple noise-absorbing grids (310) are uniformly arranged on its inner wall surface. The noise-absorbing grids (310) include radial grid ribs and circumferential dividing plates, which are arranged in a grid-like combination, so that the acoustic cavity structure (300) forms a composite tuning cavity with multiple sound wave scattering paths.

2. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The damping sandwich structure (120) includes a die-cast groove segment and an elastic sandwich body disposed in the groove segment. The inner surface of the groove segment has a limiting rib protrusion extending in the circumferential direction, so that the elastic sandwich body is restricted from radial sliding under vibration loading. The outer side of the elastic interlayer body is in contact with the inner wall of the main shell (100) by mechanical embedding or micro-protrusion inlay, and its inner side is attached to the outer wall of the inner shaft cylinder (200), so that the elastic interlayer forms a double-sided attachment structure.

3. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The shaft end cap (110) is provided with a plurality of reinforcing ribs (130) extending in the axial direction at the junction with the main housing (100). Each reinforcing rib (130) is continuously formed between the outer wall of the shaft end cap (110) and the transition section of the main housing (100), and its cross-section is trapezoidal or arc trapezoidal, which is used to form a torsional stiffness enhancement zone in the end cap area.

4. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The acoustic cavity structure (300) is composed of an inner arc wall, an outer arc wall and two end arc-shaped closed walls. It has a three-dimensional ring arc structure as a whole, and multiple segmented cavities are arranged along the circumference of the shell. Adjacent cavities are separated from each other by spacer ribs, so that different cavity segments form multiple independent but controllable acoustic units with resonant frequency bands.

5. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The noise-reducing grille (310) includes: Multiple radially extending first ribs, each having its two ends connected to the inner arc wall and the outer arc wall, respectively; Multiple second ribs extending circumferentially are located between adjacent first ribs and divide the acoustic cavity structure (300) into several open rectangular or arc-shaped grids; The size, proportion, and orientation of the grid formed by the first rib and the second rib are designed according to the wavelength of the target noise frequency band, so that the sound waves generate scattering, reflection, and local reflection paths in the cavity.

6. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The peak height of each microwave texture structure (400) is distributed in a gradual manner in the radial direction of the shell, and its cross-section is in an asymmetrical curve shape, so that the microwave texture structure (400) forms a direction-dependent bending stiffness change when loaded, and thus generates local energy dissipation during the vibration propagation of the shell.

7. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The microwave textured structure (400) and the reinforcing ribs (130) on the shaft end cap (110) are arranged in an interlaced manner in space, so that the corrugated stiffness band on the outside of the main shell (100) and the reinforcing band of the end cap transition section overlap each other to form a composite reinforcement network with multi-path load diversion capability.

8. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The damping interlayer structure (120), acoustic cavity structure (300) and microwave texture structure (400) are arranged in sequence along the radial direction of the shell, and their geometric parameters, distribution density and circumferential layout together constitute a multi-level vibration attenuation system.

9. The high-strength die-cast automotive steering gear housing according to claim 1, characterized in that, The radial distance of the annular interlayer space formed between the inner cylinder (200) and the main shell (100) varies periodically along the circumference, and the amplitude of the periodic variation matches the thickening zone of the damping interlayer structure (120).

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