CN2641609Y - Automatic testes for rubber torque-vibration damper - Google Patents

Abstract

An automatic test device for rubber torsional vibration dampers, including a computer, a power amplifier, a vibration exciter, a vibration absorber, an acceleration sensor, a charge amplifier, and a sound card in the computer to generate a series of frequency continuously increasing by the signal software in the signal generation module The sinusoidal AC signal is output to the power amplifier. The sinusoidal AC signal is amplified by the power amplifier and then applied to the exciter. The exciter that generates mechanical vibration transmits the vibration to the shock absorber. The vibration condition of the shock absorber is determined by the The acceleration sensor on the shock absorber measures, and the charge amplifier converts the charge signal into a voltage signal, and then amplifies the signal and transmits it to the sound card in the computer. The whole test system has high integration, small space occupation, light weight, easy to carry, and low equipment cost. The automation of the entire detection process greatly reduces the professional technical requirements for operators. The test is fast and convenient, the performance is reliable, and the adaptability is wide.

Description

Rubber torsional vibration damper automatic test device

technical field

The utility model relates to an automatic testing device for a rubber torsional vibration damper, which belongs to the testing technology of an internal combustion engine.

Background technique

At present, the characteristic testing technology of rubber shock absorbers is far from meeting the needs of production and matching. There is no testing method available for production in China, and only B&K equipment can be used in the performance testing of rubber shock absorbers in the world, but the price is very expensive. In addition, B&K's products are general-purpose equipment for vibration testing, which is inconvenient to use for testing rubber shock absorbers.

The commonly used test methods in scientific research are:

1. Free attenuation vibration method

In this method, the shock absorber is regarded as a single-degree-of-freedom vibration system, and the vibration is attenuated under the action of the initial disturbance torque, and its amplitude changes according to the law of exponential attenuation, so as to determine the natural frequency and logarithmic attenuation coefficient. However, how to apply an ideal initial disturbance torque and how to control the magnitude of the torque are the main obstacles restricting this method for batch detection. Therefore, this method is not suitable for more accurate and stable measurement of the natural frequency and damping of the rubber torsional vibration absorber.

2. Transfer function discrimination method

In this method, a hammer is used to hammer the shock absorber, and the real frequency, imaginary frequency and phase frequency diagram of the frequency response function are measured, so as to obtain the frequency and damping ratio. But there are also problems with this approach. Because the test system of the rubber torsional shock absorber is not a real single-degree-of-freedom system, the peak value of the high-frequency part is often high when measuring the transfer function, especially when measuring the acceleration admittance. It is easy to make the test Those who ignore the real peak of the fundamental frequency and mistakenly regard the peak of the high frequency as the peak of the fundamental frequency will cause large errors in the test results.

3. Sine sweep method

This method uses the sinusoidal excitation generated by the exciter to scan the shock absorber within a certain frequency range, and finds out its natural frequency and damping ratio coefficient according to the corresponding characteristics of the shock absorber. Compared with the above two methods, this method has higher requirements on equipment and operators, but the result is stable and reliable.

Contents of the invention

The utility model is based on the principle of the sinusoidal scanning method, a set of dedicated automatic detection device for the rubber shock absorber used in the internal combustion engine. The automatic detection device generates a series of sinusoidal alternating current signals with continuously increasing frequency by the signal generating module. The data analysis module analyzes and calculates the collected signals to obtain the final test constant. The automatic test device includes a computer with a data analysis module and a signal generation module, a power amplifier, a vibration exciter, a shock absorber, an acceleration sensor, a charge amplifier, the data analysis module is composed of data analysis software and a sound card, and the signal generation module is composed of a signal generator It is composed of software and sound card; the sound card generates a series of sinusoidal alternating current signals with continuously increasing frequency by the signal generation software in the signal generation module, and outputs them to the power amplifier. The sinusoidal alternating current signal is amplified by the power amplifier and then applied to the exciter. The frequency of the signal output by the computer is the same, and the exciter that generates mechanical vibration transmits the vibration to the shock absorber. The vibration condition of the shock absorber is measured by the acceleration sensor installed on the shock absorber. Proportional to the vibration acceleration, the charge amplifier converts the charge signal into a voltage signal, then amplifies the signal and transmits it to the sound card, and the sound card transmits the collected signal to the data analysis software. The test device solves the problem of high requirements for testers and test conditions in general test methods, and has the following characteristics:

1. The whole test system is highly integrated, takes up little space, is light in weight, easy to carry, and the cost of equipment is low

Inexpensive.

2. The automation of the whole process of testing process - data analysis - testing report greatly reduces the need for operators

The professional and technical requirements of the staff.

3. It is not necessary to go on the engine bench during the test, but to measure independently. Fast and convenient testing, reliable performance,

Wide adaptability.

4. Use ordinary sound card instead of data acquisition card.

Description of drawings

Figure 1 is a schematic diagram of the composition of the rubber torsional vibration damper test device.

Figure 2 is a flow chart of the testing software.

The main structure in the figure is: computer 1, power amplifier 2, vibration exciter 3, shock absorber 4, acceleration sensor 5, charge amplifier 6, data analysis module 7, sound card 8, data analysis software 9, signal generation module 10, signal Produce software 11, sound card 12.

Detailed ways

The rubber torsional vibration damper automatic test device includes a computer 1 with a data analysis module 7 and a signal generation module 10, a power amplifier 2, a vibration exciter 3, a shock absorber 4, an acceleration sensor 5 and a charge amplifier 6, as shown in the accompanying drawing 1, wherein the signal generation module 10 is composed of signal generation software 11 and sound card 12, and the data analysis module 7 is composed of data analysis software 9 and sound card 8.

When using the device for detection, the signal generating software 11 in the signal generating module 10 generates a series of sinusoidal alternating current signals with continuously increasing frequency, which are output to the power amplifier 2 through the sound card 12 . The sinusoidal alternating current signal is amplified by the power amplifier 2 and applied to the coil of the exciter 3 . The coil with alternating current generates mechanical vibration in the magnetic field, the frequency of which is the same as the frequency of the signal output by the computer 1 . The mechanical vibration generated by the exciter 3 is transmitted to the magnetic chuck by the vibration transmission rod, and then transmitted to the inertia block of the shock absorber 4 by the magnetic chuck, so that the inertia block generates forced vibration. The vibration condition of the shock absorber 4 is measured by an acceleration sensor 5 installed on the shock absorber 4 . The amount of charge generated by the acceleration sensor 5 is proportional to the vibration acceleration of the shock absorber 4 . The charge amplifier 6 converts the charge signal into a voltage signal, amplifies the signal and transmits it to the computer 1 . The sound card 8 in the data analysis module 7 transmits the collected signal to the data analysis software 9 . The data analysis software 9 analyzes and calculates the collected signals to obtain the final test parameters: natural frequency and damping coefficient of the rubber torsional vibration absorber.

The signal generation software 11 and the data analysis software 9 in the computer 1 are compiled by C++Builder in the whole detection device, see accompanying drawing 2. The signal generation software 11 adopts a circular structure of scanning data, that is, by calling the API function of Windows, a series of sinusoidal signals with gradually increasing frequency and constant amplitude are generated. The increasing step size of the sinusoidal signal remains unchanged and is determined by the initialization of the test software, and the frequency range of the generated sinusoidal signal is also determined during the software initialization phase. The generated sinusoidal signal is transmitted to the power amplifier 2 through the headphone channel output of the sound card 12 .

The main function of the data analysis software 9 is: the resonance signal amplified by the charge amplifier 6 is transmitted to the data analysis software 9 through the mic channel of the sound card 8 . The data analysis software 9 performs accurate frequency spectrum analysis and processing on the data. The processing method is to convert the collected response data (sinusoidal acceleration data) at each frequency point of the shock absorber 4 into amplitude, and find out all excitation vibrations within the detection range. The maximum amplitude point of the point and the 1/2 maximum amplitude point, and then calculate the ω ₀ and ξ of the shock absorber 4. The data analysis software 9 also includes functions such as data tracking, graphic display, and curve scaling, so as to obtain more detailed and intuitive analysis results at each frequency of the shock absorber 4 .

Claims (1)

1. rubber torsional vibration damper automatic testing equipment, it is characterized in that: this automatic testing equipment comprises the computing machine (1) of band data analysis module (7) and signal generating module (10), power amplifier (2), vibrator (3), vibration damper (4), acceleration transducer (5), charge amplifier (6), data analysis module (7) is made up of data analysis software (9) and sound card (8), and signal generating module (10) produces software (11) by signal and sound card (12) is formed; Sound card (12) produces software (11) with the signal in the signal generating module (10) and produces the simple alternating current electric signal that a series of frequencies increase progressively continuously, output to power amplifier (2), the simple alternating current electric signal amplifies after-applied in vibrator (3) by power amplifier (2), its frequency is identical with the signal frequency of computing machine (1) output, the vibrator (3) that produces mechanical vibration is passed to vibration damper (4) with vibration, the vibration state of vibration damper (4) is measured by the acceleration transducer (5) that is installed on the vibration damper (4), the quantity of electric charge that acceleration transducer (5) produces is directly proportional with the vibration acceleration of vibration damper (4), charge amplifier (6) is converted to voltage signal with charge signal, signal is amplified again and be delivered in the sound card (8), sound card (8) passes to data analysis software (9) with gathering the signal of returning.