Testing system for NVH problem of automobile four-wheel drive system

Abstract

The utility model discloses an automobile four-wheel drive system NVH problem test system, and relates to the automobile NVH test technology field, the automobile four-wheel drive system NVH problem test system comprises an NVH test device and sensors arranged on an automobile four-wheel drive assembly to be tested, the sensors are respectively arranged on a transfer case output end housing, a transmission shaft middle support and a rear differential input end housing; amplitude and frequency of vibration appearing at the three positions are timely and accurately detected, targeted improvement is carried out on the three positions, key vibration sources can be effectively restrained, and driving quality of the whole vehicle is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of automotive NVH testing, and particularly to a testing system for NVH problems of an automotive four-wheel drive system. Background Technique

[0002] NVH is the English abbreviation of Noise, Vibration, and Harshness; as Figure 1 shown, the existing structure of the four-wheel drive transmission system mainly includes a transfer case assembly 1, a drive shaft 2, a middle bracket 3, and a rear differential assembly 4. The power input end of the transfer case assembly 1 is directly connected to the output shaft of the transmission or through a universal transmission device. The power output end 1B of the transfer case assembly 1 is connected to a drive shaft 2. The power input end 4A of the rear differential assembly 4 is connected to a drive shaft 2. The power output end 4B of the rear differential assembly 4 is connected to the left and right rear output shafts. The two drive shafts 2 are connected through a universal coupling. The drive shaft 2 is supported by a middle bracket 3, and one side of the middle bracket 3 is connected to the vehicle body. During the development of automotive NVH, when it comes to the four-wheel drive system, common problems include abnormal vibration of the floor and booming noise inside the vehicle during high-speed driving. How to quickly diagnose such problems has become an urgent matter.

[0003] The patent document with the name "Off-line NVH Testing System and Method for Transmission Assembly" (document number CN112881014B) discloses a technical solution including a host computer, a testing module, and a data acquisition module. The host computer is respectively connected to the testing module and the data acquisition module. The testing module is used to connect to the transmission assembly to be tested and provide the working speed and working torque required for testing the transmission assembly to be tested according to the testing control instruction of the host computer. The host computer analyzes the vibration acceleration signal, sound pressure signal, and rotation speed signal generated by the transmission assembly to be tested during testing in the testing module collected by the acquisition module, and judges whether the tested transmission assembly is qualified according to the analysis result. However, the technical solution of this document does not disclose the specific installation positions of the sensors in the data acquisition module, and cannot accurately and timely detect the corresponding vibration sources, resulting in low diagnostic efficiency. Content of the Utility Model

[0004] The purpose of the utility model is to provide a testing system for NVH problems of an automotive four-wheel drive system to accurately and timely detect the corresponding vibration sources.

[0005] The utility model can be realized through the following technical solutions: A testing system for NVH problems of an automotive four-wheel drive system includes NVH testing equipment and sensors arranged on the four-wheel drive assembly of the vehicle to be tested. The sensors are respectively arranged on the output end housing of the transfer case, the middle bracket of the drive shaft, and the input end housing of the rear differential.

[0006] Compared with the prior art, the utility model has the following beneficial effects:

[0007] Vibrations are likely to occur at the output end housing of the transfer case, the middle support of the drive shaft, and the input housing of the rear differential. By installing sensors at these three positions, the amplitudes and frequencies of the vibrations occurring at these three locations can be detected in a timely and accurate manner. Targeted improvements can be implemented to effectively suppress the key vibration sources and improve the driving quality of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic structural diagram of an automotive four-wheel drive system in the prior art;

[0009] Figure 2 is a schematic diagram of the installation position of the sensor on the transfer case assembly;

[0010] Figure 3 is a schematic diagram of the installation position of the sensor on the middle support of the drive shaft;

[0011] Figure 4 is a schematic diagram of the installation position of the sensor on the rear differential assembly. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0012] Please refer to Figures 1 - 4 As shown, a test system for NVH problems of an automotive four-wheel drive system includes NVH test equipment and sensors arranged on the four-wheel drive assembly of the vehicle to be tested. The sensors are respectively arranged at the output end housing 10 of the transfer case, the middle support 20 of the drive shaft, and the input housing 30 of the rear differential; in the automotive four-wheel drive system, the power output end 1B of the transfer case assembly 1 is connected to the drive shaft, and vibrations are likely to occur at the output end housing 10 of the transfer case; the middle support 20 of the drive shaft is used to support the drive shaft, and there is also a universal coupling near this position, and vibrations are likely to occur on the middle support 20 of the drive shaft; the power input end 4A of the rear differential assembly 4 is connected to the drive shaft, and vibrations are likely to occur at the input housing 30 of the rear differential; by installing sensors at these three positions, the amplitudes and frequencies of the vibrations occurring at these three locations can be detected in a timely and accurate manner. Targeted improvements can be implemented to effectively suppress the key vibration sources and improve the driving quality of the whole vehicle.

[0013] The middle support 20 of the drive shaft includes a bearing seat 21 and a support 22 connected together. A sensor is arranged at the connection position between the support 22 on the middle support 20 of the drive shaft and the vehicle body; the sensor is at Figure 3It is not shown in the figure. The bracket 22 is bolted to the vehicle body. The sensor can be installed at the threaded hole at this position to facilitate the installation of the sensor on the bracket 22 and can accurately detect the vibration at this position. In particular, there is no need to provide a sample with a complex structure. The sensor can be directly installed and connected by using the connection part of the designed part, and the measurement result can directly reflect the rationality of the modal design of the designed part.

[0014] A sensor is provided at the connection position between the bearing seat 21 on the middle bracket 20 of the drive shaft and the bracket 22; the sensor is Figure 3 not shown in the figure. The bearing seat 21 and the bracket 22 are also bolted together. The sensor can be installed at the connection position between the bearing seat 21 and the bracket 22 through this bolt and can accurately detect the vibration at this position. In particular, there is no need to provide a sample with a complex structure. The sensor can be directly installed and connected by using the connection part of the designed part, and the measurement result can directly reflect the rationality of the modal design of the designed part.

[0015] A sensor is provided on the front mount 311 provided on the rear differential housing 31 away from the input housing 30 of the rear differential; when a fault occurs in the transmission assembly to be tested, the vibration generated by the rear differential housing 31 is relatively obvious. By providing a sensor on the front mount 311 and the front mount 311 is provided on the side connected to the vehicle body, the vibration at the front mount 311 is detected.

[0016] A sensor is provided on the rear mount 312 provided on the rear differential housing 31 away from the input housing 30 of the rear differential; the vibration generated by the rear differential housing 31 is relatively obvious. By providing a sensor on the rear mount 312 and the rear mount 312 is provided on the side connected to the vehicle body, the vibration at the rear mount 312 is detected.

[0017] The said sensor includes a vibration sensor and a rotational speed sensor; the vibration sensor detects the vibration at each position, and the rotational speed sensor detects the rotational speed of the transmission assembly to be tested.

Claims

1. A test system for NVH problems of a four-wheel drive system of an automobile, comprising an NVH test device and a sensor arranged on the four-wheel drive assembly of the automobile to be tested, characterized in that: The sensors are respectively arranged on the transfer case output end housing (10), the transmission shaft middle bracket (20) and the rear differential case input end housing (30).

2. The NVH problem testing system for the four-wheel drive system of an automobile according to claim 1, characterized in that: The transmission shaft middle bracket (20) comprises a bearing seat (21) and a bracket (22) connected together, and a sensor is arranged at a connection position between the bracket (22) on the transmission shaft middle bracket (20) and the vehicle body.

3. The testing system for NVH problems of automobile four-wheel drive system according to claim 2, characterized in that: A sensor is arranged at the connection position between the bearing seat (21) and the bracket (22) on the middle bracket (20) of the transmission shaft.

4. The testing system for NVH problems of automobile four-wheel drive system according to claim 1, characterized in that: A sensor is arranged on a front suspension (311) arranged on a rear differential housing (31) away from a rear differential input end housing (30).

5. The testing system for NVH problems of automobile four-wheel drive system according to claim 4, characterized in that: A sensor is provided on a rear suspension (312) arranged on a rear differential housing (31) away from a rear differential input end housing (30).

6. The test system for NVH problems of automobile four-wheel drive system according to claim 3 or 5, characterized in that: The sensors include a vibration sensor and a rotation speed sensor.

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