KR20060013111A - Device for measuring balancing utilizing soft bearing type rotor - Google Patents

Abstract

The present invention relates to a balancing instrument of a flexible bearing type, and more particularly, by electronically calculating the mass unbalance and the correction mass on the rotating body in order to reduce the vibration phenomenon due to the mass unbalance generated in the rotating body and performing mass correction. The present invention relates to a balancing bearing of a flexible bearing type capable of reducing vibration.

Balancing measuring device of the flexible bearing method of the present invention, the fixing means for fixing the rotating body (10); Rotating body rotating means (14) for rotating the rotating body at a predetermined rotational speed; Phase measuring means (16) for measuring the phase of the rotating body; First and second displacement measuring means (18,19) for measuring displacement of the rotating body; Amplifying means (20) for amplifying the displacement detection signal output from the first and second displacement measuring means (18, 19) into a signal of a predetermined size; A / D conversion means 22 for converting the signal output from the phase measuring means 16 and the amplifying means 20 into a digital signal; And detecting the mass unbalance state of the rotating body by using the phase and displacement signals inputted from the A / D converting means 22 by receiving information about the rotating body 10 and calculating a mass correction value for the corresponding rotating body. Calculation and balancing means 24.

Balancing, Rotor, Mass, Unbalance, Phase, Displacement, Measurement, Flexible, Bearing

Description

Device for measuring balancing utilizing soft bearing type rotor}

1 is a block circuit diagram of a balancing instrument according to the present invention;

2 is a perspective view of an embodiment of a rotating body accommodating part according to the present invention;

3 is a state diagram of a balancing phase measurement signal according to the present invention;

4 is a front view of a balancing instrument according to the present invention;

5 is a flowchart illustrating an operation state of the calculation and balancing means according to the present invention;

6 is an initial menu screen at the time of balancing operation,

7 is a menu screen for setting physical information and a balancing method of a rotating body;

8 is a menu 2 screen for storing the results measured when performing a balancing operation once,

9 shows a menu 3 screen for setting additional functions;

10 is a utility screen for making vectors of various directions into a single vector;

11 is a utility screen for dividing a vector into two specific angle vectors;

12 is a menu screen for filling the shape and dimensions of the rotating body.

13 is a menu screen for dimensioning the shape of the selected rotating body,

14 is a screen for storing a database and modifying specific data when performing a balancing operation;

15 is a final result display screen after performing a balancing operation once,

16 is a program menu configuration diagram of a balancing tester.

<Description of the symbols for the main parts of the drawings>

10: rotating body 12: fixing means

14: rotation means 16: phase measurement means

18: first displacement measuring means 19: second displacement measuring means

20: amplification means 22: A / D conversion means

24: Compute and Balancing Means

The present invention relates to a balancing instrument of a flexible bearing type, and more particularly, by electronically calculating the mass unbalance and the correction mass on the rotating body in order to reduce the vibration phenomenon due to the mass unbalance generated in the rotating body and performing mass correction. The present invention relates to a balancing bearing of a flexible bearing type capable of reducing vibration.

Many rotating bodies (rotors), such as a rotating shaft for power transmission, are used for machinery and mechanism devices. Such a rotating body requires a uniform state of mass distribution, but mass unbalance may occur due to carelessness in manufacturing process or problems in manufacturing technology. When such mass unbalance occurs, many problems occur as the rotating body rotates, and particularly, many problems are exposed in a process requiring high precision and quietness.

This will be described in detail as follows.

In the case of a general machine equipped with a plurality of rotors, if one of the rotors has a mass unbalance in which the center of gravity of the rotor and the geometric axis of center do not coincide, vibration is generated accordingly. The vibration generated in this way causes severe wear on other parts, such as bearings, shafts, spindles, gears, etc. to fix the rotating body or to the rotating body, and to reduce the life of each part.

In addition, the vibration of the rotating body may damage the structure by generating a harmful stress to support the structure, the energy is not used for the purpose of the equipment is consumed in the form of vibration energy is reduced efficiency.

On the other hand, the vibration is transmitted to the adjacent machine through the base, which causes serious damage to the accuracy and inherent function of the adjacent machine.

In order to solve this problem, balancing of the rotating body is performed. Balancing, according to the definition of ISO, refers to the process of examining the mass distribution of a rotor and making adjustments to ensure that the vibrations of the journal and the bearing forces, if necessary, are within certain limits at frequencies corresponding to the operating speed. That is, a series of acts of removing or attaching mass to adjust the center of gravity on the rotating body in order to reduce the vibration caused by mass unbalance generated only in the rotating machine.

A balancing machine conventionally used to perform such balancing is configured to electronically detect rotational imbalance. However, most of the balancing machines depend on imports, which is very expensive, and it takes a lot of time to repair them in case of failure, which causes a great deal of trouble. Therefore, there is a demand for the development of a device that can be repaired at a low cost and in case of failure.

The present invention is to solve the above problems, an object of the present invention is to electronically calculate the mass unbalance and the correction mass on the rotating body in order to reduce the vibration phenomenon due to mass unbalance generated in the rotating body by performing mass correction It is to provide a balancing bearing of the flexible bearing method that can reduce the vibration.

Another object of the present invention is to provide a flexible bearing-type balancing instrument that can be repaired quickly and inexpensively, and secures dynamic balancing technology.

Balancing measuring device of the flexible bearing method of the present invention for achieving the above object, the fixing means for fixing the rotating body; Rotating body rotating means for rotating the rotating body at a predetermined rotational speed; Phase measuring means for measuring a phase of the rotating body; First and second displacement measuring means for measuring displacement of the rotating body; Amplifying means for amplifying the displacement detection signal output from the first and second displacement measuring means into a signal of a predetermined size; A / D conversion means for converting the signal output from the phase measuring means and the amplifying means into a digital signal; And calculating and balancing means for detecting mass unbalance of the rotating body and calculating a mass correction value for the corresponding rotation by receiving information about the rotating body and using phase and displacement signals inputted from the A / D converting means. Characterized in that.

Hereinafter, with reference to the accompanying drawings, a balancing meter of the flexible bearing method of the present invention will be described in detail.

The configuration of the balancing instrument of the present invention, referring to the block circuit diagram of Figure 1, the fixing means for fixing the rotating body (10); Rotating body rotating means (14) for rotating the rotating body at a predetermined rotational speed; Phase measuring means (16) for measuring the phase of the rotating body; First and second displacement measuring means (18,19) for measuring displacement of the rotating body; Amplifying means (20) for amplifying the displacement detection signal output from the first and second displacement measuring means (18, 19) into a signal of a predetermined size; A / D conversion means 22 for converting the signal output from the phase measuring means 16 and the amplifying means 20 into a digital signal; And detecting the mass unbalance state of the rotating body by using the phase and displacement signals inputted from the A / D converting means 22 by receiving information about the rotating body 10 and calculating a mass correction value for the corresponding rotating body. Computation and balancing means 24.

The rotating body 10 is an object for measuring mass unbalance and is fixed to be rotatable at high speed for measurement. The present invention has been developed to be applied to the dynamic balancing of the pendulum-type flexible bearing method, it can be applied to the RPM 30 ~ 6000, amplitude 50㎛ class measuring instruments.

2 shows an example of a receptacle for rotatably fixing the rotating body 10. Both ends of the rotating body 10 to be measured are fixed by fixing means 12 which rotatably support like a bearing. First and second displacement measuring means 18 and 19 for measuring the displacement of the rotating body 10 at two points are installed on the upper part of the rotating body 10, and phase measurement is performed on one side of the rotating body 10. Means 16 are provided.

In addition, the rotating means 14 for rotating the rotating body 10 is provided at the bottom. The pivot means 14 is constructed using a motor and is operated in accordance with control commands transmitted from the calculation and balancing means 24. In particular, the rotation means 14 is preferably configured to be able to change the number of revolutions. The bottom pipes are the supports.

The position measuring means 16 may be configured using a photoelectric sensor, and the first and second displacement measuring means 18 and 19 may have a displacement sensor having a sensitivity of 247 mV RPM / mil. It can be configured using.

Compared with the position measuring means 16, since the signal output from the first and second displacement measuring means 18 and 19 is weak in size, the amplified means 20 amplifies and outputs a sufficient size signal. . The amplification means 20 can be configured, for example, using an OP amplifier.

The signals output from the position measuring means 16 and the amplifying means 20 are converted into digital signals by the A / D conversion means 22 as analog signals. The A / D conversion means 22 is a relatively inexpensive NI product manufactured by using a PCI-6023E board having 16 analog inputs of 200 kS / s. Of course, it can be configured using another A / D conversion board that can perform the same function.

The signal output from the A / D conversion means 22 is input to the calculation and balancing means 24. The calculation and balancing means 24 converts an input signal into a required form to detect an unbalanced state of the rotating body 10 and calculates and displays a mass correction value, which is conventionally used as a monitor, a main body, and a keyboard. It can be easily configured using an industrial PC including a mouse, and the like. In this case, in order to facilitate the user interface, it is preferable to provide a touch screen input means in addition to an input device such as a keyboard and a mouse.

The operating state of the calculation and balancing means 24 according to the invention is shown in the flowchart of FIG. 5.

When the balancing meter starts to be operated by the user, the double-sided balancing or the single-sided balancing is set by the user, and accordingly, the storage frequency is set three times or two times, respectively. When the rotating body 10 rotates, an electrical signal is generated from the position measuring means 16 and the first and second displacement measuring means 18 and 19, and processed by the A / D conversion means 22, and then It is input to the balancing means 24. At this time, it is checked whether data is normally acquired, and if normal, filter processing is performed on the acquired data.

In the present invention, a non-contact displacement meter measuring method is used. This method represents a vector in which the rotational frequency vector is physically rotated in the same direction as the heavy spot moves on the machine. Indicates to move.

3 is a diagram showing a phase measurement state for calculating balancing in a state where the position measuring means 16 and the first and second displacement measuring means 18 and 19 are installed. It can be seen that the phase angles differ depending on the clockwise direction and the counterclockwise direction.

The principle of measurement is as follows.

The phase angle measurement on the instrument using the axial displacement sensor (displacement measuring means) is the distance from the axial displacement sensor to the high spot measured in the rotation direction when the phase reference is positioned below the phase reference sensor. . The high spot is the position on the mass unbalanced axis of rotation that is the longest distance from the center of rotation. The high spot is the response of the axis to mass unbalance and becomes the closest part to the concentric fixture surface as the axis rotates, appearing in the vibration pick up as the position of maximum amplitude in the + direction. Heavy and high spots may or may not coincide and vary relative to the critical speed of the rotor.

Therefore, the delay angle is a measure of the distance that the high spot reaches the axis displacement sensor from the time when the phase reference mark passes the phase reference sensor. This can be used to store the time when the phase sensor is read by software, to store the time when the maximum value of the displacement sensor is read, and to measure the phase angle using the two time differences. It can calculate the frequency of the vibration, including.

On the other hand, since the noise is included in the input signal, a desired frequency is detected by using a fast Fourier transform (FFT), and a lowpass filter is filtered to remove unwanted high frequency bands. Also, a moving average filter is used to smooth the output signal. This filter process is performed before performing signal analysis. The low pass filter and the moving average filter may be included in the calculation and balancing means 24 or in the A / D conversion means 22.

The signal analysis of the acquired data is performed as described above. If the signal is stable, the maximum value and phase angle are stored. If the maximum number and phase angle storage frequency satisfy the set number of times, an unbalance amount is calculated. The set number of times may determine the number of times to obtain the most satisfactory result through the measurement.

The calculation of the unbalance of the rotating body is carried out using the influence coefficient method. The influence coefficient method is a concept that starts from the assumption that the unbalance amount and vibration value of the rotating body are directly proportional. The influence coefficient becomes a variable of the system. This method is very precise in the case of rigid rotors (rigid rotors), and in the case of flexible rotors operating in speed ranges above the first dangerous speed, some theoretical deformation is required. Same as

The influence coefficient method is represented by Equation 1 below.

<Equation 1>

Where W is the measurand (complex), ?? is the coefficient of influence coefficient (complex), and U is the unbalance (complex).

On the other hand, the measurand is an amount that can be measured by the first and second displacement measuring means 18,19, that is, the displacement sensor, and the unbalance amount and the influence coefficient value are unknown. Since there are two unknowns and one equation, to solve this formula, we make two more equations using the "Trial Weight," which we already know.

Equation 1 is attached to the test weight (T; Trial Weight) is shown as Equation 2. The purpose of the test weight is to give the original vector the same size and opposite direction.

<Formula 2>

Subtracting Equation 2 from Equation 1 results in Equation 3.

<Equation 3>

Substituting Equation 3 into Equation 1 is equivalent to Equation 4.

<Equation 4>

?? and U ₀ can be obtained as described above. At this time, the magnitude and phase of the vibration amount should be measured and corrected in the form of a complex number to be substituted into the above equation. In addition, U obtained above is equal to the unbalance amount and the corrected weight and magnitude, and the direction should be reversed. Therefore, the correction weight Uc = -U is set, and the complex number is converted into the magnitude and phase. Can be calculated.

The test weight for balancing is finally installed in the machine after it is replaced by a permanent weight once the corrected weight and installation location have been determined. By doing so, the rotating body in which the balancing is performed has an effect of significantly reducing the occurrence of vibration that has occurred conventionally even if it rotates in the installed state.

4 is a front view of the balancing instrument of the flexible bearing method according to the present invention. Referring to the drawings, a monitor screen is displayed on the upper portion, and a keyboard for data input is provided on the lower portion. Data input is the length, weight, weight of test weight, etc. of the rotor.

6 to 16 is a menu screen of the operating state of the balancing bearing of the flexible bearing method according to the present invention.

6 is an initial menu screen displayed when performing a balancing operation using the balancing meter of the present invention. The phase and magnitude to be measured are displayed on the screen while balancing the specific rotating body, and the contents of the next task are briefly described through the status information window.

7 is a screen of Menu 1 for setting physical information and a balancing method of a rotating body. Balancing grades and balancing measurement methods (compensation weight attachment / removal, cross-section, double-sided balancing) that must be satisfied for the balancing test and the compensation method according to the type of rotor in the measurement can be input directly by the user using the keypad. have. It also provides the ability to view and modify saved measurements from previous balancing tasks.

FIG. 8 is a screen of Menu 2 for storing a result measured when a balancing operation is performed once, and FIG. 9 is a screen of Menu 3 used to set other additional functions.

10 is a utility screen for making vectors into one vector when there are vectors in multiple directions.

11 is a utility screen for calculating how a vector is divided at two specific angles when there is a single vector.

The rotor has a tab that can be calibrated at a certain angle. However, if the balancing result does not match the determined tap angle, divide it into two vectors corresponding to the adjacent angles to have the same effect as the measured balancing result. The user corrects the degree of balancing of the rotating body by removing or attaching the corrected weight corresponding to this divided angle.

FIG. 12 is a screen for selecting a shape of the rotating body and a balancing method to be tested. FIG. 13 is a screen made to accurately fill in the shape of the rotating body selected by FIG. .

14 is a screen for storing data measured when a balancing operation is completed. The user can not only reload the previously stored data to rebalance, but also modify specific data, and the data at that time is stored as a database.

15 is a screen showing a final result after performing a balancing operation once. In general, the end result is often inconsistent with the angle of the tap defined on the rotor. In this case, the user may decompose / synthesize the balancing result at a specific angle as shown in FIG. 10 or 11 through the “Vector Split” menu in FIG. 6, and correct the balancing of the rotating body through this data.

16 is a screen diagram illustrating a menu screen of a balancing measuring instrument according to the present invention.

Referring to the operational state of the dynamic balancing measuring instrument of the flexible bearing method of the present invention having the configuration as described above as follows.

The present invention implements a rotary flexible bearing balancing instrument directly, and the measurement methods provided include single plane balancing and two plane balancing. Here, description will be given using double-sided balancing as an example.

Click on the "Menu" button in Figure 6 to balance the rotor.

When clicked, the menu 1 screen shown in FIG. 7 is displayed. In this state, the "Rotor Setup" button is clicked, and a screen as shown in FIG. 12 is output, and a rotor having a desired shape is selected from various types of rotors. To end the selection, click the "Exit" button in FIG.

Remove all test weights attached to the rotor.

Rotate the rotor.

In FIG. 6, an unbalance amount and an angle (not shown) corresponding to each surface are displayed.

Observe the indicated Stability Bar on the left side of FIG. 6 to determine stabilization.

When the stabilization is completed, press the "Read Value" button of FIG.

Stop the rotor.

Attach the test weight to the left side of the rotor.

Enter the weight and angle of the test weight using the keypad.

Rotate the rotor.

Observe the stability bar on the left side of FIG. 8 to determine stabilization.

When it is stabilized, press the "Read Value" button of FIG.

Stop the rotor.

Attach the test weight to the right side of the rotor.

Enter the weight and angle of the test weight using the keypad.

Rotate the rotor.

Observe the stability bar on the left side of FIG. 6 to determine stabilization.

When it is stabilized, press the "Read Value" button of FIG.

When the "read value" button of FIG. 6 is clicked on, a final result screen indicating the correction weight for the mass imbalance as shown in FIG. 15 is output.

Stop the rotor.

If the final result angle is not an angle that can be corrected, clicking the "Vector split" button of FIG. 6 shows the result of splitting with the balanced result shown in FIG. 6.

In FIG. 6, when a surface for which Vector Split is desired is clicked, a value corresponding to the surface is displayed, and the selected surface blinks.

As described above, after the correction weight and the correction angle of the rotating body are calculated electronically, a weight replacing the corrected weight is attached to complete the correction of the rotating body.

According to the present invention, in order to reduce the vibration phenomenon due to the mass unbalance generated in the rotating body, the vibration can be reduced by electronically calculating the mass unbalance and the corrected mass on the rotating body and performing mass correction. It is effective in providing a flexible bearing type balancing instrument that can be repaired quickly when it occurs and secures dynamic balancing technology.

Claims (8)

An apparatus for detecting mass unbalance of a rotating body and calculating corrected weight, Fixing means (12) for fixing the rotating body (10); Rotating body rotating means (14) for rotating the rotating body at a predetermined rotational speed; Phase measuring means (16) for measuring the phase of the rotating body; First and second displacement measuring means (18,19) for measuring displacement of the rotating body; Amplifying means (20) for amplifying the displacement detection signal output from the first and second displacement measuring means (18, 19) into a signal of a predetermined size; A / D conversion means 22 for converting the signal output from the phase measuring means 16 and the amplifying means 20 into a digital signal; And detecting the mass unbalance state of the rotating body by using the phase and displacement signals inputted from the A / D converting means 22 by receiving information about the rotating body 10 and calculating a mass correction value for the corresponding rotating body. Balanced measuring instrument of the flexible bearing method characterized in that it comprises a calculation and balancing means (24). The method of claim 1, Balanced measuring instrument of the flexible bearing method, characterized in that the position measuring means (16) is a photo sensor. The method of claim 1, And said first and second displacement measuring means (18,19) are displacement sensors having a sensitivity of 247 mV RPM / mil. The method of claim 1, Balanced measuring instrument of the flexible bearing method, characterized in that the calculation and balancing means 24 is an industrial PC. The method of claim 4, wherein Balanced measuring instrument of the flexible bearing method characterized in that the industrial PC further comprises a keyboard, a mouse, as well as a touch screen input means. The method of claim 1, Flexible bearing type, characterized in that the calculation and balancing means 24 calculates the frequency, phase angle, and maximum value using the phase measurement signal and two displacement signals inputted through the A / D conversion means 22. Balancing instrument. The method of claim 1, Balanced measuring instrument of the flexible bearing method characterized in that for performing the signal processing using a low pass filter and a moving average filter for the signal input through the A / D conversion means (22). The method of claim 1, And said calculating and balancing means (24) calculates an unbalance amount using an influence coefficient method.

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