A kind of NVH vibration isolation testing device of tubular column body sealing cover

Abstract

The utility model belongs to the field of automobile test, concretely relates to a kind of NVH vibration isolation testing device of column body sealing cover.The device includes listening room and sound room, and microphone is arranged in listening room and sound room, and microphone is used to measure sound pressure level SPL;Loudspeaker is arranged in sound room, for emitting noise;Sound room and listening room are isolated using steel plate and vibration isolation board, the steel plate is arranged in the middle part of the vibration isolation board, and the vibration isolation board is arranged as three layers;The middle part of the steel plate is opened, and the size and shape of the opening are according to the body design of specific project.The utility model testing device can compare the transmission loss value of full-closed steel plate;It is not a single absolute transmission loss value comparison.The utility model device can carry out more scientific and reasonable test and evaluation to body sealing cover.

Description

Technical Field

[0001] This utility model belongs to the field of automotive testing, specifically relating to an NVH vibration isolation testing device for a column body sealing cover. Background Technology

[0002] The steering column connects the steering wheel inside the passenger compartment to the steering gear outside. This requires passing through the body panels, meaning the panels need openings. To prevent dust and mud from entering the passenger compartment through these openings, a sealing cover is installed between the steering column and the body. Furthermore, with the increasing prevalence of new energy vehicles, especially electric vehicles, which lack engine noise sources, the requirements for NVH (Noise, Vibration, and Harshness) performance in automobiles are becoming increasingly stringent. In addition to its dust and water protection functions, the sealing cover between the steering column and the body also has NVH vibration isolation requirements. The design intent is to prevent external noise and vibration from perceiving or causing customer complaints through this body panel opening.

[0003] Current industry status: Although the functional requirements of the sealing cover are known, there is a lack of good testing equipment for the vibration isolation performance of the column body sealing cover design because noise and vibration can also be transmitted through the body sheet metal. Utility Model Content

[0004] To address the aforementioned problems, this utility model provides an NVH (Noise, Vibration, and Harshness) isolation testing device for a vehicle body sealing cover. This device provides a more scientific and reasonable evaluation of the sealing cover's vibration isolation performance. The specific technical solution is as follows:

[0005] A vibration damping and NVH testing device for a tubular body sealing cover includes a receiving chamber and a sound-generating chamber. Microphones are installed in both chambers for measuring sound pressure level (SPL). A loudspeaker is installed in the sound-generating chamber to emit noise. The receiving chamber and the sound-generating chamber are separated by a steel plate and a vibration damping plate. The steel plate is located in the middle portion of the vibration damping plate, which is configured as a three-layer structure. An opening is made in the middle portion of the steel plate, the size and shape of which are designed according to the specific vehicle body design of the project.

[0006] Furthermore, the steel plate is provided with a vehicle body sealing cover, or a fully enclosed steel plate is used.

[0007] Furthermore, the steel plate is selected based on the sheet metal of the test vehicle to simulate the thickness and material of the body sheet metal.

[0008] The steps for NVH vibration isolation testing and evaluation of the column body sealing cover using the above-mentioned testing equipment are as follows:

[0009] (1) The loudspeakers in the sound room emit noise, producing a white noise signal (400-10000 Hz) that is at least 20 dB higher than the background noise.

[0010] (2) Measure the sound pressure level (SPL) using the microphone in the sound-emitting chamber and the microphone in the receiving chamber respectively; the sound-emitting chamber is SPLe and the receiving chamber is SPLr. Calculate the transmission loss TL = SPLe - SPLr.

[0011] (3) Conduct a test using a fully enclosed steel plate and calculate TLcl based on the results;

[0012] (4) Test again using steel plate + body sealing cover, and calculate Tlse based on the results;

[0013] (5) When the noise is ≤ 2.5 kHz and TLcl - TLse ≤ 3 dB, the vibration isolation performance of the vehicle body sealing cover is acceptable. The acceptable value of this method can also be adjusted according to the NVH requirements of the whole vehicle.

[0014] This invention's testing device can compare transmission loss values ​​for fully enclosed steel plates, rather than comparing a single absolute transmission loss value. This device allows for more scientific and reasonable testing and evaluation of vehicle body sealing covers. Attached Figure Description

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

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] like Figure 1 As shown, an NVH (Noise, Vibration, and Harshness) vibration isolation testing device for a tubular vehicle body sealing cover is disclosed. The device includes a receiving chamber and a sound-generating chamber, both equipped with microphones for measuring sound pressure levels (SPL). A loudspeaker is installed in the sound-generating chamber to emit noise. The receiving chamber and the sound-generating chamber are separated by a steel plate and a vibration damping plate. The steel plate is positioned in the middle section of the vibration damping plate, which is configured as a three-layer structure. An opening is formed in the middle section of the steel plate, the size and shape of which are designed according to the specific vehicle body for the project. A vehicle body sealing cover is installed outside the steel plate, or a fully enclosed steel plate is used. The steel plate simulates the thickness and material of the vehicle body sheet metal based on the sheet metal selection of the test vehicle.

[0018] The steps for NVH vibration isolation testing and evaluation of the column body sealing cover using the above-mentioned testing equipment are as follows:

[0019] (1) The loudspeakers in the sound room emit noise, producing a white noise signal (400-10000 Hz) that is at least 20 dB higher than the background noise.

[0020] (2) Measure the sound pressure level (SPL) using the microphone in the sound-emitting chamber and the microphone in the receiving chamber respectively; the sound-emitting chamber is SPLe and the receiving chamber is SPLr. Calculate the transmission loss TL = SPLe - SPLr.

[0021] (3) Conduct a test using a fully enclosed steel plate and calculate TLcl based on the results;

[0022] (4) Test again using steel plate + body sealing cover, and calculate Tlse based on the results;

[0023] (5) When the noise is ≤ 2.5 kHz and TLcl - TLse ≤ 3 dB, the vibration isolation performance of the vehicle body sealing cover is acceptable. The acceptable value of this method can also be adjusted according to the NVH requirements of the whole vehicle.

[0024] The preferred embodiments of this patent have been described in detail above. However, this patent is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this patent.

Claims

1. An NVH (Noise, Vibration, and Harshness) isolation testing device for a column-type vehicle body sealing cover, characterized in that: The device includes a receiving room and a sound-generating room, both equipped with microphones for measuring sound pressure level (SPL). A loudspeaker is installed in the sound-generating room to emit noise. The sound-generating room and the receiving room are separated by a steel plate and a vibration damping plate. The steel plate is located in the middle of the vibration damping plate, which is configured as a three-layer structure. The middle part of the steel plate has openings, the size and shape of which are designed according to the specific vehicle body of the project.

2. The NVH vibration isolation testing device for a column body sealing cover according to claim 1, characterized in that: The steel plate is equipped with a vehicle body sealing cover or is a fully enclosed steel plate.

3. The NVH vibration isolation testing device for a column body sealing cover according to claim 1, characterized in that: The steel plate is selected based on the sheet metal of the test vehicle to simulate the thickness and material of the body sheet metal.

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