Noise reduction type automobile shock absorber

Abstract

The utility model relates to the technical field of automobile shock absorbers, in particular to a noise reduction type automobile shock absorber which comprises a shock absorber body, a piston rod, an upper connecting plate, an NDI buffer block and a metal ring, a circle of clamping groove is formed in the position, close to the shock absorber body, of the NDI buffer block, the metal ring is installed in the clamping groove, and the section of the metal ring is in an I shape. A bump array is arranged on the surface of an inner hole of the NDI buffer block, convex ribs are uniformly arranged on the surface of the end part of the NDI buffer block, and bumps I are uniformly arranged on the surface of the other end part of the NDI buffer block. Compared with the prior art, by adopting the collaborative design of the I-shaped section metal reinforcing ring and the noise reduction texture on the surface of the NDI buffer block, the contact area of a metal-NDI material is reduced by 40%, concentrated friction is converted into multi-point dispersed friction by utilizing the convex rib structure, and on the premise that the basic bearing capacity is kept, the weight is not increased and the durability is not lost, the NDI buffer block has the advantages of being simple in structure and convenient to operate.

Description

Technical Field

[0001] This utility model relates to the field of automotive shock absorber technology, specifically a noise-reducing automotive shock absorber. Background Technology

[0002] Traditional automotive shock absorbers feature a metal ring as the buffer block, with full-circumferential contact between the buffer block and the metal ring, resulting in an excessively large friction area. The buffer block is made of NDI (naphthalene diisocyanate). Under dynamic loads, the metal-NDI interface between the metal ring and the buffer block easily generates high-frequency whistling due to contact surface friction. Actual measurements show that the sound pressure level reaches as high as 68dB in the 1500-3000Hz frequency band, severely impacting ride comfort.

[0003] With the increasing NVH performance standards for new energy vehicles, controlling abnormal noises in the suspension system has become a core challenge. Due to the battery pack layout, the suspension vibration modes of new energy vehicles become more complex, and the vibration spectrum shifts to the high-frequency range of 2000-3500Hz, further aggravating the transmission of friction noises.

[0004] Existing noise reduction solutions have significant bottlenecks: Lubricating coating method: Although it can reduce the friction coefficient in the short term, the coating durability is insufficient, and the noise reduction effect decreases by 60% after 50,000 cycles; Surface polishing process: Although shot peening the metal reinforcing ring reduces noise by 3-5dB, the processing cost increases by 30%.

[0005] Therefore, it is necessary to design a noise-reducing automotive shock absorber to reduce the contact area between the metal ring and the NDI buffer block and disperse the friction force, thereby effectively solving the problem of high-frequency abnormal noise in the suspension system of electric vehicles without increasing weight or sacrificing durability. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a noise-reducing automotive shock absorber that reduces the contact area between the metal ring and the NDI buffer block and disperses friction, thereby effectively solving the problem of high-frequency abnormal noise in the suspension system of electric vehicles without increasing weight or losing durability.

[0007] To achieve the above objectives, this utility model is a noise-reducing automotive shock absorber, comprising a shock absorber body, a piston rod, an upper connecting plate, an NDI buffer block, and a metal ring. One end of the piston rod is located inside the shock absorber body, and the other end of the piston rod is fitted with the upper connecting plate. The piston rod passes through the inner hole of the NDI buffer block, and the end of the NDI buffer block is embedded in the back of the upper connecting plate. The NDI buffer block has a groove near the shock absorber body, and the metal ring is installed in the groove. The cross-section of the metal ring is I-shaped. The inner hole surface of the NDI buffer block has a raised dot array, the end surface of the NDI buffer block has uniformly arranged raised ribs, and the other end surface of the NDI buffer block has uniformly arranged raised dots. One end of the exhaust groove is connected to the inner hole of the NDI buffer block, and the other end of the exhaust groove extends to the outer surface of the NDI buffer block.

[0008] The piston rod is connected to the upper connecting plate by a thread.

[0009] The upper connecting plate has through holes on both sides.

[0010] The NDI buffer block consists of three layers of buffer structure, with the outer diameter of the three layers decreasing sequentially. An annular groove is provided at the transition between two adjacent buffer layers, and the slot is an annular groove near the damper body.

[0011] The NDI buffer block is interference-fitted with the upper connecting plate, and the protruding structure on the inner surface of the upper connecting plate is engaged and fixed with the mounting groove on the surface of the NDI buffer block.

[0012] The bump array includes 9 layers of bump rings, which are arranged axially along the inner hole of the NDI buffer block. Each layer of bump rings consists of several bumps.

[0013] The damper body is a twin-tube damper structure, and the twin-tube damper structure has a piston valve and a bottom valve inside.

[0014] Compared with the prior art, this utility model adopts a collaborative design of an I-shaped cross-section metal reinforcing ring and a noise-reducing texture on the surface of the NDI buffer block. Through geometric reconstruction, the contact area between the metal and NDI materials is reduced by 40%. The convex rib structure transforms concentrated friction into multi-point dispersed friction. Under the premise of maintaining the basic load-bearing capacity, without increasing weight or sacrificing durability, the friction noise of the NDI buffer block during the compression stroke is significantly reduced, effectively solving the problem of high-frequency abnormal noise in the suspension system of electric vehicles. It is especially suitable for new energy vehicles with stringent NVH performance requirements. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 This is a partial sectional view of the present invention.

[0017] Figure 3 This is a schematic diagram of the structure of the NDI buffer block and metal ring of this utility model.

[0018] Figure 4 This is a front view of the NDI buffer block and metal ring of this utility model.

[0019] Figure 5 This is a side view of the NDI buffer block and metal ring of this utility model.

[0020] Figure 6 This is a cross-sectional view of the NDI buffer block and metal ring of this utility model.

[0021] Figure 7 This is a schematic diagram of the structure of the metal ring of this utility model.

[0022] Figure 8 This is a cross-sectional view of the metal ring of this utility model. Detailed Implementation

[0023] The present invention will now be further described with reference to the accompanying drawings.

[0024] See Figure 1 , Figure 2 This utility model relates to a noise-reducing automotive shock absorber, comprising a shock absorber body 1, a piston rod 2, an upper connecting plate 3, an NDI buffer block 4, and a metal ring 5. One end of the piston rod 2 is located inside the shock absorber body 1, and the other end of the piston rod 2 is mounted on the upper connecting plate 3. The piston rod 2 passes through the inner hole of the NDI buffer block 4, and the end of the NDI buffer block 4 is embedded in the back of the upper connecting plate 3. See also Figures 3-6 The NDI buffer block 4 has a groove 4-1 near the damper body 1, and a metal ring 5 is installed in the groove 4-1. The cross-section of the metal ring 5 is I-shaped. The I-shaped metal ring 5 optimizes the contact between the metal ring 5 and the NDI buffer block 4 from surface contact to two annular line contacts, which can reduce frictional noise. At the same time, during the compression process of the NDI buffer block 4, the material of the NDI buffer block 4 after being compressed will be squeezed into the gap of the I-shaped cross-section, improving the durability of the material. Figure 7 , Figure 8 As shown.

[0025] The inner surface of the NDI buffer block 4 has a bump array 4-3, which includes nine layers of bump rings arranged axially along the inner hole of the NDI buffer block 4. Each layer of bump rings consists of several bumps. The bump array 4-3 is designed to ensure that the friction between the NDI buffer block 4 and the piston rod 2 is point contact after being compressed, thereby minimizing friction noise. The end surface of the NDI buffer block 4 has uniformly arranged ribs 4-4, and the other end surface of the NDI buffer block 4 has uniformly arranged bumps 4-5. The arrangement of bumps 4-5 and ribs 4-4 further reduces friction noise.

[0026] One end of the exhaust groove 4-2 is connected to the inner hole of the NDI buffer block 4, and the other end of the exhaust groove 4-2 extends to the outer surface of the NDI buffer block 4. The exhaust groove 4-2 is used to discharge the air in the gap between the inner hole of the NDI buffer block 4 and the outer diameter of the piston rod 2 when the NDI buffer block 4 is compressed, thereby effectively avoiding noise.

[0027] The piston rod 2 is threadedly connected to the upper connecting plate 3. The upper connecting plate 3 is made of cast aluminum. The upper connecting plate 3 has through holes 3-1 on both sides for connecting to the vehicle body.

[0028] The NDI buffer block 4 consists of three layers of buffer structure. The outer diameter of the three layers of buffer structure decreases sequentially. An annular groove is provided at the transition between two adjacent buffer structures. The slot 4-1 is an annular groove near the damper body 1.

[0029] To ensure a stable connection, the NDI buffer block 4 is interference-fitted with the upper connecting plate 3, and the raised structure on the inner surface of the upper connecting plate 3 is engaged and fixed with the mounting groove 4-6 on the surface of the NDI buffer block 4.

[0030] The damper body 1 is a traditional twin-tube damper structure. The twin-tube damper structure has a piston valve and a bottom valve inside to provide damping force.

[0031] The I-shaped cross-section reduces the contact area between the metal ring 5 and the NDI buffer block 4 to two linear support areas, thereby reducing the friction noise source by 70% and the measured sound pressure level in the 1500-3000Hz frequency band by 10dB.

[0032] By setting 0.5mm high gradient bumps 4-5, ribs 4-4, and bump array 4-3 at both ends and the inner surface of the NDI buffer block, the concentrated friction energy is dispersed to 120 contact points through the friction path discretization design, and the peak intensity of abnormal noise is reduced by 40%.

[0033] Experiments show that, compared with traditional structures, this invention reduces the working noise of the buffer block by 12dB while maintaining the same load-bearing capacity, without any additional weight or loss of durability.

[0034] This invention employs a collaborative design of an I-shaped cross-section metal reinforcing ring and a noise-reducing texture on the surface of the NDI buffer block. Through geometric reconstruction, the contact area between the metal and NDI materials is reduced by 40%. The convex rib structure transforms concentrated friction into multi-point dispersed friction. While maintaining basic load-bearing capacity, without increasing weight or sacrificing durability, it significantly reduces the friction noise of the NDI buffer block during the compression stroke, effectively solving the problem of high-frequency abnormal noise in electric vehicle suspension systems. It is especially suitable for new energy vehicles with stringent NVH performance requirements.

Claims

1. A noise-reducing automotive shock absorber, comprising a shock absorber body (1), a piston rod (2), an upper connecting plate (3), an NDI buffer block (4), and a metal ring (5), characterized in that: One end of the piston rod (2) is located inside the damper body (1), and the other end of the piston rod (2) is equipped with an upper connecting plate (3). The piston rod (2) passes through the inner hole of the NDI buffer block (4), and the end of the NDI buffer block (4) is embedded in the back of the upper connecting plate (3). The NDI buffer block (4) is provided with a groove (4-1) near the damper body (1). The metal ring (5) is installed in the groove (4-1). The cross section of the metal ring (5) is I-shaped. The inner hole surface of the NDI buffer block (4) has a protrusion array (4-3). The end surface of the NDI buffer block (4) has uniformly arranged ribs (4-4). The other end surface of the NDI buffer block (4) has uniformly arranged protrusions (4-5). One end of the exhaust groove (4-2) is connected to the inner hole of the NDI buffer block (4), and the other end of the exhaust groove (4-2) extends to the outer surface of the NDI buffer block (4).

2. The noise-reducing automotive shock absorber according to claim 1, characterized in that: The piston rod (2) and the upper connecting plate (3) are connected by threads.

3. The noise-reducing automotive shock absorber according to claim 2, characterized in that: The upper connecting plate (3) has through holes (3-1) on both sides.

4. The noise-reducing automotive shock absorber according to claim 1, characterized in that: The NDI buffer block (4) consists of three buffer structures. The outer diameter of the three buffer structures decreases sequentially. An annular groove is provided at the transition between two adjacent buffer structures. The slot (4-1) is an annular groove near the damper body (1).

5. A noise-reducing automotive shock absorber according to claim 1, characterized in that: The NDI buffer block (4) is interference-fitted with the upper connecting plate (3), and the protruding structure on the inner surface of the upper connecting plate (3) is engaged and fixed with the mounting groove (4-6) on the surface of the NDI buffer block (4).

6. A noise-reducing automotive shock absorber according to claim 1, characterized in that: The bump array (4-3) includes 9 layers of bump rings, which are arranged along the axial direction of the inner hole of the NDI buffer block (4). Each layer of bump rings consists of several bumps.

7. A noise-reducing automotive shock absorber according to claim 1, characterized in that: The damper body (1) is a twin-tube damper structure, and the twin-tube damper structure has a piston valve and a bottom valve inside.

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