CN100335881C - Test-bed for testing performance of vibration damping belt pulley wheel - Google Patents

Abstract

The invention relates to a vibration-absorbing pulley performance test bench, which comprises a bench (1), a motor (2) and a tested vibration-damping pulley (9) on its shaft, a load (3) and a pulley (303) on its shaft , tensioning pulley (4); signs (904, 903) are respectively provided on the side walls of the outer ring (902) and the inner ring (901) of the tested vibration-damping pulley (9); Mark sensors (601, 602) for sensing marks (903, 904), laser displacement sensors (501) for measuring the radial displacement of the tested vibration-damping pulley (9), used for measuring the tested vibration-damping pulley (9) ) a laser displacement sensor (502) for axial displacement; the output end of each sensor is connected with the computer system. The test bench of the present invention can simulate the actual operating conditions of the vibration-absorbing pulley, and will use the sensor to detect the parameters such as the resonance amplitude of the wheel surface and the relative torsion of the inner and outer rings, and output the measured parameters to the computer system for analyzing and comparing the parameters .

Description

Vibration-absorbing pulley performance test bench

technical field

The invention relates to automobiles, in particular to test equipment used for testing the performance of vibration-absorbing pulleys on automobiles during the design process of automobiles.

Background technique

During the driving process of the car, due to the different natural frequencies of the internal parts, the imbalance of the wheels, the engine and the running system, and other factors can easily cause strong vibrations of the whole vehicle and parts. This vibration affects the power, economy, comfort and safety of the car.

Automotive engine accessory gear train refers to a system that drives accessories such as water pumps, fans, generators, and air-conditioning compressors through the main shaft wheel. The main shaft wheel as a driving component is directly connected to the crankshaft, and its running stability directly affects the working state of the accessories and the working quality of the engine. However, when the car is running, the crankshaft system and the complete engine will vibrate due to the uneven road surface, as well as the periodic changes of the gas pressure in the cylinder and the unbalanced inertial force of the moving parts. When the crankshaft is subjected to periodically changing disturbance forces, the engine and transmission system will generate strong torsional vibrations. As a vibration excitation source, this torsional vibration has a great impact on the working quality and life of other transmission systems.

The use of the vibration-absorbing pulley is to reduce the impact of the exciting vibration of the engine and crankshaft on the accessory gear train, and to buffer the impact of the engine when it is excited. The damping belt pulley is a composite wheel, and its structure is shown in Figure 3, and it is made up of inner and outer rings 901, 902 and damping rubber 905 between the inner and outer rings. The outer ring 902 is a steel spinning part, and the inner ring 901 is a stamping part. The difference between the vibration-absorbing pulley and the ordinary pulley is that there is an extra ring of vibration-damping rubber 905, which is the key to the entire vibration-damping pulley. It can reduce the resonance amplitude during the operation of the pulley and slow down the impact during speed change.

Vibration-absorbing rubber uses rubber elasticity. Compared with widely used metal springs (usually metal springs can only use elasticity in one direction), it has three-way (vertical, horizontal, longitudinal) spring constants. Appropriate selection of the shape and size of the anti-vibration rubber can make the spring constants in the three directions reach the desired values. At the same time, in order to reduce the amplitude of the resonance and stop the free attenuation vibration generated by the impact as soon as possible, the spring needs to have a damping effect. The internal friction of vulcanized rubber is more than 1000 times greater than that of metal springs. The rubber is attenuated by internal friction. The internal friction of rubber is generated by the interaction between rubber molecules and between rubber molecules and fillers. Therefore, Especially suitable for high frequency vibration.

Vibration-absorbing pulleys can be used for water pump wheels, fan wheels, main shaft wheels, air-conditioning compressor tension pulleys, shock absorbers, sensor pulleys, automobile brake pads, etc. in automobiles. Judging from the current application situation of production enterprises, the damping pulley is still in the exploratory stage due to the limitations of technology and process conditions. The main reason is that the damping mechanism of rubber is similar to the damping spring. To ensure the best effect, it is necessary to select a suitable damping coefficient C. _P , but the current design and production units lack the damping coefficient C _P test means, and the performance of the designed damping pulley cannot be tested.

Contents of the invention

The technical problem to be solved by the present invention is to provide a vibration-absorbing pulley performance test bench, which can simulate the actual operating conditions of the vibration-damping pulley, and will use sensors to detect parameters such as the resonance amplitude of the wheel surface and the relative torsion of the inner and outer rings. And output the measured parameters to the computer system for analyzing and comparing the parameters.

The technical solution adopted by the present invention to solve the problems of the technologies described above is:

Vibration-absorbing pulley performance test test bench, which includes the bench, the tested vibration-damping pulley on the motor and its shaft, the load and the pulley on its shaft, and the tension pulley; the tested vibration-damping pulley, the pulley, and the tension pulley pass through the belt To form a wheel train; the outer ring of the tested vibration-absorbing pulley and the side wall of the inner ring are respectively provided with a second mark and a first mark; the stand is provided with a first mark sensor for sensing the first mark on the inner ring, The second mark sensor for sensing the second mark on the outer ring, the first laser displacement sensor for measuring the radial displacement of the tested vibration-damping pulley, and the second laser displacement sensor for measuring the axial displacement of the tested vibration-damping pulley Sensors; the output terminals of each sensor are connected with the computer system.

In the above solution, an infrared temperature sensor for measuring the temperature of the tested vibration-damping pulley is also provided on the bench, and the output end of the infrared temperature sensor is connected to the computer system.

In the above solution, the load is composed of a generator and a resistance box, and the output terminal of the generator is connected to the input terminal of the resistance box.

In the above solution, the platform includes a panel, and the motor, generator, and resistance box are arranged below the panel; the gear train and various sensors are arranged above the panel.

In the above scheme, the first mark sensor, the second mark sensor, the first laser displacement sensor, the second laser displacement sensor, and the infrared temperature measuring sensor are arranged on the stand through a support; the support is composed of a pole and a cantilever, and the upper end of the pole It is connected with the cantilever, and the lower end of the pole is connected with the stand.

In the above scheme, the first laser displacement sensor and the second laser displacement sensor are arranged on a bracket, and the first laser displacement sensor for measuring the radial displacement of the tested vibration-damping pulley is arranged on the pole for measuring the vibration-absorbing pulley. The second laser displacement sensor for the axial displacement of the vibration pulley is arranged under the cantilever.

In the above solution, the first marker sensor and the second marker sensor are respectively arranged on two brackets, and they are both arranged under the cantilever.

In the above solution, the infrared temperature sensor is arranged under the cantilever.

In the above solution, the motor is a frequency-variable speed-regulating motor, and the frequency-variable speed-regulating motor is controlled by a computer.

Because there are many parameters that can affect the performance of the belt pulley, the present invention mainly selects the parameters to be measured based on the consideration of the following aspects:

1) The amplitude-frequency characteristics of the damping pulley during operation are closely related to the smoothness of engine operation, the service life of the damping pulley and the noise of the engine. Therefore, the vibration frequency and amplitude of the pulley must be detected.

2) Since the vibration-damping rubber is an elastic object, when the speed of the vibration-damping pulley reaches a certain value, there will be a twist or relative rotation between the inner and outer rings, that is, a phase difference between the inner and outer rings. Appropriate relative torsion is good for reducing the vibration of the pulley and buffering the impact, but if the torsion angle is too large, or the relative rotation between the inner and outer rings occurs continuously during high-speed operation, it will have a great impact on the safety of the pulley and even the engine. To do this, the phase difference between the inner and outer rings of the damping pulley must be detected.

3) Since the vibration-damping pulley runs at high speed, the temperature of the pulley will inevitably rise as the working time increases. Excessively high temperature will cause the aging of the inner rubber ring and also affect the service life of the V-ribbed belt. Therefore, a certain method is adopted to detect the temperature of the pulley, so as to facilitate the analysis of the relationship between the operating state and temperature of the pulley, as well as the temperature and service life.

Therefore, the present invention chooses to measure the frequency and amplitude of the exciting vibration of the pulley during operation, the phase difference between the inner and outer rings of the pulley, and the temperature of the pulley. Of course, the test bench of the present invention can also be used to measure other parameters.

The working principle of the test bench of the present invention is as follows: the test bench is driven by the output power of the motor to drive the tested vibration-damping pulley, and the tested vibration-damping pulley forms a wheel train through the belt, the tensioner pulley and the load driving wheel to drive the load to run, simulating the vibration-damping pulley The laser displacement sensor is used to measure the amplitude, frequency characteristics and stability of the vibration-absorbing pulley during operation. The marker sensor measures the twist or relative rotation that occurs between the inner and outer rings, that is, the phase difference between the inner and outer rings. The output terminals of each sensor are connected with the computer system, and provide parameters to the computer system for data analysis and processing by the computer.

The present invention has the advantages of:

1. Since the pulley runs at a high speed, it is difficult to adopt a contact temperature measurement method. Therefore, the present invention uses a non-contact infrared temperature sensor with high precision to measure the temperature of the damping pulley.

2. The motor adopts a variable frequency speed regulating motor. The computer can change the output speed and torque by changing the frequency of the motor, and control the operation of the motor to simulate different operating conditions such as engine start, acceleration, deceleration and normal operation, which can be simulated very realistically. The operating conditions of the engine, so that various sensors detect the performance parameters of the damping pulley more accurately, and the frequency conversion servo speed regulating motor has high operating accuracy and stable operation.

3. The load is composed of a generator and a resistance box. The size of the load can be changed by changing the resistance of the resistance box to truly simulate the operation of the car.

4. The present invention has simple structure and low cost.

Description of drawings

Fig. 1 is the front view of the structure of the embodiment of the present invention

Figure 2 is a top view of the structure of the embodiment of the present invention

Figure 3 is the positional relationship between the tested vibration-absorbing pulley and the sensor

Figure 4 is a positional diagram of the tested vibration-absorbing pulley and the sensor

Figure 5 is a top view of the tested vibration-absorbing pulley

Figure 6 is a block diagram of the signal processing principle of the computer system

Detailed ways

As shown in Figures 1 and 2, the test bench of the embodiment of the present invention includes a bench 1, a motor 2 and a tested vibration-damping pulley 9 on its shaft, a load 3 and a pulley 303 on its shaft, and a tension pulley 4. The motor 2 is a variable frequency speed regulating motor, which is controlled by a computer. The tested vibration-damping pulley 9, the pulley 303, and the tension pulley 4 form a wheel train through the belt 10. As shown in Figure 5, the wheel surface of the outer ring 902 of the tested vibration-damping pulley 9 and the wheel surface of the inner ring 901 draw a white line second mark 904 and first mark 903 through the center of the tested vibration-damping pulley; A first mark sensor 601 for sensing the first mark 903 on the inner ring 901, a second mark sensor 602 for sensing the second mark 904 on the outer ring 902, and a radial direction for measuring the vibration-damping pulley 9 under test are provided. The first laser displacement sensor 501 for displacement, the second laser displacement sensor 502 for measuring the axial displacement of the tested vibration-damping pulley 9 , and the infrared temperature sensor 7 for measuring the temperature of the tested vibration-damping pulley 9 . The output terminals of each sensor are connected with the computer system.

The load 3 is composed of a generator 302 and a resistance box 301 , the output end of the generator 302 is connected with the input end of the resistance box 301 .

The platform 1 includes a panel 101 , the motor 2 , the generator 302 , and the resistance box 301 are arranged below the panel 101 ; the gear train and various sensors are arranged above the panel 101 .

The variable frequency motor can be controlled by a servo controller or by a host computer, and the host computer and the controller communicate bidirectionally through the RS232 serial port. In the embodiment of the present invention, the operation of the motor is controlled by the host computer, so that the operation of the engine under different working conditions can be tested more conveniently and accurately. The communication between the upper computer and the frequency conversion controller is realized with VC++ language.

As shown in Figures 3 and 4, marker sensors 601, 602, laser displacement sensors 501, 502, and infrared temperature sensor 7 are arranged on the stand 1 through a support 8; the support 8 is composed of a pole 801 and a cantilever 802, and the pole 801 The upper end of the pole is connected with the cantilever 802, and the lower end of the pole 801 is connected with the stand 1. Two laser displacement sensors 501, 502 are arranged on a support 8, and the laser displacement sensor 501 for measuring the radial displacement of the tested vibration-damping pulley 9 is arranged on the pole 801 for measuring the axial displacement of the tested vibration-damping pulley 9 The laser displacement sensor 502 is set under the cantilever 802 . The two mark sensors 601, 602 are respectively arranged on the two brackets 8, and they are all arranged below the cantilever 802; the test beams of the two mark sensors 601, 602 are respectively aligned with the white line marks 903, 904 on the inner and outer rings 901, 902 . The infrared temperature sensor 7 is arranged below the cantilever 802 .

Whole damping belt pulley performance test system comprises the present invention's test bench and computer system, as shown in Figure 6, the output signal of the infrared temperature sensor 7 on the test bench, the laser displacement sensor 501,502 passes through the signal conditioning circuit first, carries out filter amplification , and then divided into two ways, one into the constant display of the voltmeter, the other into the A/D conversion, and finally into the computer for related data processing and analysis.

On the test stand, the embodiment of the present invention adopts the laser displacement sensor (model OD25-05) imported from Germany to test the vibration of the vibration-reducing pulley 9 during rotation. The laser sensor has high measurement accuracy and can reach The output is in the order of μm, and the output is an analog quantity, which can reflect various vibration states of the pulley in the process of rotation in real time. The laser displacement sensor is a current output with a range of 4-20mA. Use the RCV420 chip to convert it to 0-5V, then pass through the zero-adjustment circuit, A/D conversion, and input it to the computer for processing.

The infrared temperature measuring sensor 7 of the embodiment of the present invention adopts the infrared temperature measuring sensor of the model IRt/c.01-K, which is an analog voltage output with a range of 0-5V. For such an output, it can be directly input into the A/D card for A/D conversion, and then the data can be analyzed and processed on the computer.

It is difficult to accurately detect the phase difference between the inner and outer rings of the pulley. The present invention draws a white line mark 903, 904 on the wheel surface at the center of the tested vibration-reducing pulley 9, so that the test beams of the two mark sensors 601, 602 Align with the white line marks 903 and 904 on the inner and outer rings respectively. In the process that tested vibration-damping belt pulley 9 rotates like this, mark sensor just sends a pulse signal (as output a high level) whenever detecting mark line. When stalling or rotating at low speed, the two flag sensors generate high levels at the same time. When the inner and outer rings are twisted, there will be a time difference when the two marker sensors generate high levels, and the phase difference between the inner and outer rings can be calculated by using this time difference. The embodiment of the present invention adopts a high-precision phase measurement circuit composed of a phase-locked loop 4046, and the precision of measuring the phase difference between two signals can reach 0.1 degree.

The embodiment of the invention can simulate various working conditions of the engine, and has the characteristics of complete measurement parameters and high measurement accuracy. In the actual use process, it can reflect the various parameters of the pulley very realistically, which provides valuable information for the design and development of the vibration-absorbing pulley in the future.

Claims (9)

1. The vibration-absorbing pulley performance test bench is characterized in that it includes a bench (1), a motor (2) and the tested vibration-reducing pulley (9) on its shaft, a load (3) and the pulley on its shaft (303), tensioning pulley (4); Tried damping belt pulley (9), pulley (303), tensioning pulley (4) form wheel train by belt (10); The outside of tested damping belt pulley (9) The side walls of the ring (902) and the inner ring (901) are respectively provided with a second mark (904) and a first mark (903); The first marker sensor (601) of the marker (903), the second marker sensor (602) for sensing the second marker (904) on the outer ring (902), the diameter sensor (602) for measuring the vibration-reducing pulley (9) to be tested The first laser displacement sensor (501) for displacement, the second laser displacement sensor (502) for measuring the axial displacement of the tested damping pulley (9); the output ends of each sensor are connected with the computer system. 2. The test bench according to claim 1, characterized in that: the bench (1) is also provided with an infrared temperature sensor (7) for measuring the temperature of the tested damping pulley (9), an infrared temperature sensor ( 7) The output terminal is connected with the computer system. 3. The test bench according to claim 1, characterized in that: the load (3) is composed of a generator (302) and a resistance box (301), and the output terminal of the generator (302) and the input of the resistance box (301) end connection. 4. The test bench according to claim 3, characterized in that: the bench (1) includes a panel (101); the motor (2), the generator (302), and the resistance box (301) are arranged on Below; the wheel train and each sensor are arranged on the top of the panel (101). 5. The test bench according to claim 2, characterized in that: the first mark sensor (601), the second mark sensor (602), the first laser displacement sensor (501), the second laser displacement sensor (502), The infrared temperature measuring sensor (7) is arranged on the stand (1) through the support (8); Connect, the lower end of pole (801) is connected with stand (1). 6. The test bench according to claim 5, characterized in that: the first laser displacement sensor (501) and the second laser displacement sensor (502) are arranged on a support (8) for measuring the vibration reduction pulley (9) The first laser displacement sensor (501) of radial displacement is arranged on the pole (801), and the second laser displacement sensor (502) for measuring the axial displacement of the tested vibration-absorbing pulley (9) is arranged on the cantilever (802) below. 7. The test bench according to claim 5, characterized in that: the first marker sensor (601) and the second marker sensor (602) are respectively arranged on two brackets (8), and they are all arranged on the cantilever (802) below. 8. The test bench according to claim 5, characterized in that the infrared temperature measuring sensor (7) is arranged under the cantilever (802). 9. The test bench according to claim 1, characterized in that: the motor (2) is a variable-frequency speed-regulating motor, which is controlled by a computer.

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