JPH02226032A - portable balancing device - Google Patents

Abstract

PURPOSE:To easily perform balancing of a rotary body by a method whereby data are sampled by rotary pulses for A/D conversion to obtain digitized data, which is order analyzed by an FFT processor, and an S/V curve is formed in an S/V circuit from the order-analyzed data. CONSTITUTION:An FFT processor 4 analyzes the order of an oscillating value of a digital signal from an A/D converter circuit 3. An S/V circuit 5 extracts only the first order component of the rotation frequency of a rotary body among the spectrum which is order analyzed by the FFT processor, with storing data of the amplitude and phase and forming an S/V curve indicating the relation between the rotation frequency and amplitude. A balance operating circuit operates the size and position from a reference position of a correcting weight to be mounted in the rotary body based on the amplitude and phase of the oscillation, and further presumes an oscillating value of the rotary body when the correcting weight is mounted thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a portapull type balancing device that can determine the amount and position of unbalance (hereinafter referred to as unbalance) occurring in a rotating body of a rotating machine.

[Conventional technology]

If the center of gravity of a rotating body and the center of rotation do not coincide with each other when it rotates, the center of gravity will rotate around the center of rotation, creating centrifugal force and generating vibrations that match the number of rotations.

This shift in the center of gravity is called unbalance of the rotating body, and the causes of this unbalance include 1) manufacturing errors of the rotating body, 2) non-uniformity of the material of the rotating body, 3) non-uniformity of the geometric shape, etc. . For this reason, the unbalance is corrected using a dedicated balancing machine when manufacturing rotating machines so that it falls within the range determined by the standard. The standard used in Japan is JISB0905.

By the way, when a number of rotating bodies are combined and integrated on-site, such as in a turbine generator or electric motor, even if each individual rotating body is accurately corrected for unbalance during factory manufacturing, the amount of unbalance remaining in each rotating body remains. may exceed the allowable value at the site, causing vibration due to unbalance. Furthermore, when the rotating bodies are connected, the centers of rotation may be shifted by an amount of assembly error, resulting in an apparent unbalance and an increase in vibration.

In such cases these imbalances are corrected by on-site field balancing operations.

In addition, in a rotating machine that has been operated for a long time, unbalance may increase due to aging of the rotating body, and vibration may increase.

If the vibration increases in this way, the unbalance of the rotating body is corrected again by Yahari field balancing work.

The above field balancing is performed by the following procedure.

(1) Measure the amplitude of vibration that matches the rotational speed and the vibration phase from a reference position previously provided on the rotating body.

(2) Next, attach a trial weight to the unbalance correction surface defined on the rotating body and perform the same measurement as in (1).

(3) Calculate the magnitude and position of the unbalance of the rotating body from the vibration vectors of (1) and (2) measured above, and the size and mounting angle of the trial weight.

The above describes correction using one correction surface, but if the unbalance cannot be determined by surface correction alone, correction using two correction surfaces is performed.

The calculations for determining these unbalances (hereinafter referred to as balance calculations) are performed by specialized engineers because they are vector calculations and require specialized knowledge.

However, recently, computers and computers that can perform program calculations have come into use. In addition, dedicated balancers that are equipped with analysis of the rotational speed component of vibration, vibration phase analysis, and balance calculation circuits have become commercially available.

[Problem to be solved by the invention]

Although imbalances are corrected using the balancers described above, these balancers have the following drawbacks.

1) Only one type of test rotation speed can determine unbalance. In other words, conventional balancers only determine unbalance based on one test rotation speed, so rotating machines that use a wide range of rotation speeds, such as inverter electric motors, industrial drive turbines, or machine tools, can vary the rotation speed depending on the material, etc. In a rotating machine that changes the field, field balancing cannot be performed accurately and quickly.

2) Determining the unbalance that satisfies the two types of test rotation speeds requires a professional engineer. In other words, it was developed for balancing long-axis turbine rotors and jet engine rotors. Balance calculation formulas for multi-speed and multi-bearing systems include the least squares method and the mode method, but these calculations require the use of a personal computer or minicomputer-based pointer, and require specialized engineers to operate. It lacks promptness and also increases usage and equipment costs. An object of the present invention is to provide a portapull type balancing device that can easily, accurately, and quickly correct the on-balance of a rotating body of a rotating machine that uses a wide range of rotational speeds at multiple types of rotational speeds. be.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a vibration detector installed in a bearing that supports a rotating body of a rotating machine to detect vibrations generated by the rotating body, and an electric signal from the vibration detector. An amplification circuit that amplifies the amplification circuit, an A/D conversion circuit that converts an analog electrical signal from the amplification circuit into a digital electrical signal, and synchronizes the sampling and start of this A/D conversion with the rotation of the rotating body. Therefore, a rotation reference pulse detector that detects a reference position provided in advance on the rotating body as an electric signal, and a sampling interval of the A/D conversion circuit are basically rotation-to-rotation, and the rotation is performed at a multiple of the order of rotation. A fast Fourier transform (hereinafter referred to as FFT) processor outputs the reference position corresponding to the order multiplied by the signal level and the phase of the signal based on the rotation reference pulse, and the rotation The S/V circuit extracts only the first-order fundamental component corresponding to the rotation speed of the body and graphs the rotation speed and its vibration level, and the ω conversion circuit starts operating using the reference pulse signal from the rotation reference pulse detector. The gate circuit to control and the specified one from the S/v circuit
A storage circuit that stores data on primary fundamental components of rotational speeds of more than one type, and calculates the amount of unbalance of the rotating body and the position of the unbalance from the reference position of the rotating body based on the output data from this storage circuit, Furthermore, a balance calculation circuit that predicts a vibration value based on the calculation result, a comparison circuit that compares the vibration prediction value from this calculation circuit with a vibration target value to determine whether or not this predicted value reaches the vibration target value, and a balance calculation circuit that predicts the vibration value based on the calculation result. A display circuit that displays the calculation results from the circuit and the comparison results from the comparison circuit, and also inputs the conditions and test procedures necessary for balance calculation, constitutes a lancing device.

[Effect]

Vibrations that occur with the rotation of rotating machinery are detected as analog signals by vibration detectors installed in the bearings, and the electrical signals of this detection output are amplified by an amplification circuit and converted into digital signals by an A/D conversion circuit. converted. At this time, A/D conversion is performed as follows. Two types of rotation marks provided in advance on the rotating body are detected as rotation pulse signals by separate rotation pulse detectors. That is, one type of rotation mark generates a rotation reference pulse once per rotation at the reference position of the rotating body.

Another type of rotation mark has its first mark set at a reference position, and the rotation marks placed at equal intervals on the circumference of the rotating body generate rotation pulses corresponding to the order of rotation. Then, the A/D conversion circuit is operated with the rotation reference pulse, and at the same time, A/D conversion sampling is performed using the rotation pulse of the order multiple, thereby converting the vibration value of the analog signal into a digital signal.

This digital signal is input to the FFT processor and FFT
The FT processor performs order analysis of the digital signal based on the rotational speed. In the 8/V circuit, only the signal level and signal phase of the first order corresponding to the rotation speed component are extracted.
/V curve is created.

In other words, only vibration data that matches the rotational speed of one rotating body is extracted. Furthermore, since the A/D conversion is always sampled using the rotational pulse signal, the number of waveforms of the signal input to the FFT processor remains constant even if the rotational speed changes.

Since the 8/V curve is displayed on the display circuit, the operator can
By specifying multiple rotation speeds to correct unbalance while looking at the V curve data, the data for the specified rotation speeds will be stored in the memory circuit, and this data will be automatically taken into the balance calculation circuit and The magnitude of the unbalance of the rotating body and the mounting position are calculated from the data, and the results are displayed.

Note that the rotation reference pulse signal and the rotation pulse signal input to the S/V curve are detected by two types of rotation pulse detectors, so as shown in Figure 2, the rotation pulse signal is different from the rotation reference pulse signal. It is divided accurately and the mutual relationship always maintains the order multiple. Therefore, even if the number of rotations increases or decreases rapidly, the periodic relationship between the rotation reference pulse and the rotation pulse maintains an order multiple, and errors due to time delays and the like do not occur. Further, the phase resolution is determined by the number of pulses multiplied by the order, and no phase error occurs even if the rotation speed changes.

Therefore, the vibration digital signal converted by the A/D conversion circuit does not include a phase error, and the FFT processor obtains a vibration vector with a resolution determined by the order multiplication, improving the accuracy of the calculated unbalance position. is planned. In addition, balancing can be performed even in machines that change rapidly.

Correction of balance calculation results The vibration value of the rotating body when the weight is attached is predicted and calculated by the balance calculation circuit, and this vibration prediction value and the target vibration value are compared by the comparison circuit, and this result is displayed as a comment. Displayed on the circuit display.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. No. 1111fi is a block diagram of the configuration of a porta-pull type balancing device according to the first embodiment of the present invention.

In Fig. 1, vibration detectors 1a and lb are vibration detectors attached to two bearings A and B that support the rotating shaft of a rotating machine, and output vibrations caused by the rotation of the rotating shaft as electrical signals. . In addition, the vibration detection direction is a six-way radius force that is likely to generate vibration due to unbalance of the rotation axis, and in a horizontal axis rotating machine, the detection direction is the horizontal direction and the vertical direction. I keep it the same. There are acceleration type, velocity, variable position, etc. vibration detectors, but they have high low frequency sensitivity and 50
A speed-type vibration sensor with good response up to frequencies of about 0Hz is used.

The amplification circuit 2 amplifies the output signals from the vibration detectors 1a and 1b to the optimum level of the signal input to an A/D conversion circuit 3 which performs A/D conversion, which will be described later. Further, the amplification circuit 2 integrates the electrical signals proportional to the velocity from the vibration detectors 1a and lb to produce an electrical signal proportional to the displacement.

The rotational reference pulse detector 11 detects a rotational heavy position previously provided on the rotating shaft, and this detection signal is input to the A/D conversion circuit 3 via a gate circuit 7, which will be described later. Note that this pulse signal is used only for the A/D conversion start operation of the A/D conversion circuit 3.

The rotational pulse detector 12 is installed in advance on the rotational shaft and detects angle marks (positions) equally divided from the position corresponding to the rotational reference position, and this detection signal is input to the A/D conversion circuit 3. , sampling for A/D conversion is performed using this rotation pulse signal.

As the rotation reference position for the rotation reference pulse and the angle mark for the rotation pulse, there are those using a disk as shown in FIG. 3, and those using a gear as shown in FIG. 4. In FIG. 3, a disk 14 is attached to the shaft end of the rotating shaft 13, and the disk 13 has a reference hole 15 for generating a rotation reference pulse and a hole 16 for generating a rotation pulse having the order of rotation. One of the reference holes 15 and one of the holes 16 are aligned on the same diameter. Each hole is detected as a pulse signal by a rotation reference pulse detector 11 and a rotation pulse detector 12. Further, the reference hole 15 serves as a reference position for attaching a trial weight or an unbalance correction weight, so that the reference hole 15 is installed in alignment with an easy-to-understand position such as an assembly mark or a keyway on a rotating body. Note that a rotational reference pulse detector 11 and a rotational pulse detector 12 are installed corresponding to the positions of the reference hole 15 and the hole 16, respectively.

These pulse detectors are composed of electrolytic rotation pulse detectors, eddy current type non-contact pulse detectors, etc., and as the rotating body rotates, rotation reference pulses and rotation pulse signals are generated by the reference holes 15 and 16. They are detected by a rotation reference pulse detector 11 and a rotation pulse detector 12, respectively. Note that 64 holes 16 are provided equally on the circumference, and 64 rotation pulse signals are detected by the rotation pulse detector 12 for every reference pulse signal.

In FIG. 4, a gear 19 is used instead of a disk, and a reference hole 15 for a rotation reference pulse is provided in the gear 19.
It is the same as the one shown in FIG. 3, except that the tooth 20 of No. 9 is used as an angle mark for generating a rotation pulse.

The AID conversion circuit 3 is composed of a 10-pin A/D converter, and converts the vibration value of the amplified analog signal output from the amplification circuit 2 into digital by the rotation reference pulse that passes from the rotation reference pulse detector 11 to the gate circuit 7. - The vibration value of the analog signal is sampled by the rotation pulse from the rotation pulse detector 12 for each rotation and converted into a digital signal.

The FFT processor 4 analyzes the order of the vibration value of the digital signal from the A/D conversion circuit 3.

The S/v circuit 5 calculates the first order of the rotation speed of the rotating body out of the spectrum analyzed by the FF'T processor 4.

A rotation reference pulse is input to the gate circuit 7, and this rotation reference pulse is inputted to the A/D conversion circuit 3 when a command to be described later from 8/V @ path 5 is input, and data sampling for A/D conversion starts. instruct.

The memory circuit 6 stores the S/V obtained from an initial test (a test that measures vibrations due to unbalance of a rotating body) and a trial test (a test that measures vibrations of a rotating body with a known trial weight attached to the correction surface). The amplitude of the vibration at a specified rotational speed to be balanced on the curve and the phase from the reference position are stored.

The balance calculation circuit 8 calculates the size and position of the correction weight to be attached to the rotating body from the reference position based on the amplitude and phase of the vibrations stored in the initial test and trial test from the storage circuit 6, and further calculates the size and position of the correction weight to be attached to the rotating body. Predicting and calculating the vibration value of the rotating body when the correction weight is attached.

The display circuit 9 displays the size and mounting position of the correction weight calculated by the balance calculation circuit 8, and the predicted vibration value on an LCD display. Further, the test conditions, ie, the minimum and maximum rotational speeds of the rotating body for correcting unbalance, the number of corrected surfaces, the E test speed number, the vibration target value, and the test flat head, ie, the initial test and trial test, are input into the LCD display.

The comparison circuit 10 compares the predicted vibration value of the rotating body by attaching the correction weight from the balance calculation circuit 8 with the vibration target value, and the comparison result is displayed on the LCD display of the display circuit 9.

The porta-pull type balancing device consists of the above configuration,
This is a locally available device that houses components such as a vibration detector and amplification circuit, making it easy to perform field balancing of rotating machinery.

Next, a method for correcting the unbalance of the rotating body using the above configuration will be explained. The rotating body of the rotating machine is gradually rotated to a rotation speed slightly higher than the rotation speed at which imbalance should be achieved. Vibration at each rotation speed is from bearings A and B.
The vibration is detected by vibration detectors 1a and lb provided in the.

The detected vibrations are input to the amplification circuit 2 and amplified, and the vibration speeds detected by the vibration detectors 1a and 1b are integrated to obtain vibration displacement. Note that the amplification level in the amplification circuit 2 is amplified to the optimum level of the signal input to the A/D conversion circuit 3. In this case, when the A/D conversion circuit 3 exceeds the level, the amplification level is automatically adjusted to the optimum level by the signal from the A/D conversion circuit 3. Further, if the input level of the human/D conversion circuit 3 is 30% or less of the range of the amplifier circuit 2 set at this time, it is automatically adjusted to the optimum level.

The output signal from the amplifier circuit 2 is input to the A/D conversion circuit 3. At this time, the rotation reference pulse detected by the rotation reference pulse detector 11 shown in FIG. 3 or 4 (shown in FIG. Digitization of the signal is started. Then, the rotation pulse from the rotation pulse detector 12 shown in FIG. 3 or 4 is sampled and the vibration data of the analog signal is converted into a digital signal every π rotation.

Note that the A/D conversion circuit is 10 pins) Since the A/D converter is used, the number of data in the A/D converter is 1.
024 points, and data for 1024/64 rotations (16 rotations) is always taken in, and this always remains constant even if the rotation speed of the rotating body changes.

The vibration digital signal from the human/D conversion circuit 3 is subjected to order analysis by the FPT processor 4. That is, with the rotation speed of the rotating machine as the first order, vibration spectra of integral multiples (referred to as orders) of the rotation speed are analyzed. This device analyzes up to the 6.25th order of rotation speed, and determines the vibration level and phase of each vibration based on the rotation reference pulse. Then, the 8/V circuit 5 extracts only the first order of the vibration spectrum whose order has been analyzed by the FFT processor 4, stores amplitude and phase data, and creates an S/V curve. This 8/V curve is a curve in which the horizontal axis represents the number of revolutions and the vertical axis represents the vibration level corresponding to each number of revolutions.

Here, the operation of the 8/V circuit 5 and the creation of the S/V curve will be explained in detail. The gate circuit 7 detects the pulse signal of the rotation reference pulse detector 11 and instructs the A/D conversion circuit 3 to start sampling. The sampled data is FFT
The processor 4 analyzes the order, and the S/V circuit 5 extracts only the first order. When the S/V circuit 5 instructs the gate circuit 7 that the data has been stored in the S/V circuit 5, the gate circuit 7 detects the next rotation reference pulse.
Instructs the A/D conversion circuit 3 to sample the next data. This work is automatically carried out from the pre-designated rotation speed at the start of the measurement to the rotation speed at the end of the measurement. This 8/V curve is created for the initial test and the trial test and is displayed on the LCD display of the display circuit 9.
A plurality of types of rotation speeds at which unbalance should be corrected are specified with a cursor on the /V ft1l line. The amplitude and phase of the vibration in the retest for these rotational speeds are stored in the storage circuit 6. The balance calculation circuit 8 takes out the vibration data from the storage circuit 6 and calculates the size of the correction weight and the mounting position from the reference position. Further, the vibration value of the rotating body when this correction weight is attached is predicted and calculated. The size and position of these correction weights and the predicted vibration values are displayed on the LCD display.

The predicted vibration value is compared with the vibration target value by the comparator circuit 10 to see if it reaches the vibration target value, and based on the comparison result, a comment is displayed on the LCD display. It is a flowchart of a procedure for correcting unbalance in the apparatus, and the unbalance correcting procedure will be explained based on FIG. 5 and FIG. 1.

In step 21, the display circuit 9 shows the operating rotation speed of the rotating machine to be unbalance corrected, that is, the minimum and maximum operating rotation speeds.
Input the number of surfaces to be corrected for unbalance correction, the test speed number of revolutions for unbalance correction, etc. The test procedure for correcting the imbalance in step 22, that is, the balancing test procedure, includes an initial test and a trial test, and one of these is set.

First, an initial test, which is the first test procedure, is set. Step 231: Rotate the trowel rotating body and start the test. In step 24, the vibration value 25 of the analog signal amplified by the amplification circuit 2 from the vibration detectors 1a and lb is converted into the vibration value 25 from the rotation reference pulse detector 11 through the gate circuit 7 by the A/D conversion circuit 3. A/D from 26 reference pulses
After instructing the start of the conversion operation, sampling is performed using the rotation pulse 27 for each rotation from the rotation pulse detector 12 and digitized. The vibration values digitized in step 28 are subjected to order analysis by the FFT processor 4 up to the 6th and 25th orders of the rotational speed. The order-analyzed vibration value is determined by S in step 29.
The /v circuit 5 extracts only the first-order component, stores the amplitude and phase data, and determines the amplitude and phase corresponding to the rotational speed ζ from the minimum input to the maximum rotational speed according to the judgment in step 30. Phase data is collected and an 8/V curve is created. In step 31, the S/V curve from the minimum to maximum rotation speed is displayed on the LCD display of the display circuit 9, and in step 32, the rotation speed at which the unbalance is to be corrected is designated with the cursor, and the vibration amplitude at this rotation speed is determined. The one-width phase is shown as shown in Fig. 86 and Fig. 7. Figures 6 and 7 show 8/V of bearings A and H of rotating machinery when the rotational speed increases, respectively.
Curve 40.41 and the amplitude and phase at rotational speeds (two speeds) 2885.5 RPM and 3490.3 RPM at which the unbalance should be corrected are shown. At step 33, the amplitude and phase at the rotational speed at which the imbalance is to be corrected are stored in the memory circuit 6. In step 34, the test procedure is determined, the initial test is completed with the above procedure, and then a trial test is performed.

In the trial test, the test procedure is set in step 22, and when the number of surfaces to be corrected is 2, first, as shown in Fig. 8, as a trial test (2), a trial weight of 4 g is placed on the correction surface 2 from the reference position of the rotating body. The test is started in step 23 by attaching it to the mounting position of 90 degrees. Then, step 32 is passed through steps 24 to 31, which are the same as the initial test.
Vibration data for balancing at the rotation speed at which the same unbalance as the initial test should be corrected was extracted.
In step 33, the amplitude and phase of vibration in bearings A and B at the rotation speed at which the unbalance should be corrected are stored in the memory circuit 6.
9 and 10, and displayed as shown in FIGS. 9 and 10. Figures 9 and 10 show 8/V curves 42.43 for bearings A and B when the rotational speed increases, and 2882.43, which is closest to the rotational speed during the initial test. ORPM and 34
The amplitude and phase at 90.3R, PM are shown.

Next, perform the trial test (1) in the same way as the trial test (2) by attaching the trial weight 4g shown in Figure 8 to the correction surface 1 at the mounting position 90.
degree and the amplitude and phase of the rotational speed to correct the unbalance are stored in the memory circuit 6 and displayed on the LCD display as in the trial test (2).

In addition, compare the vibration vectors obtained from the trial test (2), (1) and the initial test, and if the difference is small, the calculation error will be large in the calculation of the correction weight in the balance calculation circuit, so try again. Increase the weight and retest. In this case, the comparison circuit compares the ratio of the vibration vector difference between the trial test and the initial test with a predetermined value and displays this on the LCD display if a retest is necessary. Perform the retest based on this display.

The vibration data for the initial test, trial test (1), (2), and one test are taken out from the memory circuit 6, and in step 35, the vibration target value is achieved in the balance calculation circuit 8 by a calculation formula using the least squares method, etc. In order to do this, the size (g) of the correction weights to be attached to the correction surfaces 1 and 2 and the attachment position (deg) from the reference position are calculated. Then, the vibration value when the correction weight is attached is predicted and calculated. These predicted vibration values and the size and mounting position of the corrected upper sill are displayed on the LCD in step 36 as shown in FIG.
displayed on the display. In Fig. 11, in order to achieve the vibration target value of 20 μ, the size and mounting position of the correction weight on correction surface 1.2 are 2.3 g and 128, respectively.
．． 22deg and 3.7g, 181.27d
g, which shows the amplitude and phase of the vibration expected in bearings A and B at this time.

The predicted vibration value is compared with the vibration target value in the comparison circuit 10 in step 37, and based on the comparison result, the
Three types of comments are displayed as shown in the figure. These comments are made for the following three cases, and appropriate comments are displayed based on the comparison results.

■If the correction weight is too large In this case, reduce the correction weight of the calculation result (@) and instruct recalculation. From this, the motion vector will be recalculated. Therefore, of course the target vibration level cannot be cleared. However, the vibration can be reduced compared to the initial value.

■If the target vibration level is too severe or if a calculation result that satisfies two speeds cannot be obtained due to the characteristics of the rotating body, in this case, change the target value and recalculate.

■If only one correction surface was selected, or if the target value is too severe to satisfy 2 speeds, in this case, increase the target value or increase the number of correction surfaces to 2 and retest.

Once the size and mounting position of the correction weight have been determined as described above, attach the correction weight to the correction surface and perform a trial test. Since the confirmation test is equivalent to the initial test, the test is conducted using the same procedure as the initial test described above. As shown in FIGS. 12 and 13, this test shows the amplitude and phase of the vibrations of bearings A and B at the S/V curve and the test speed. In Figures 12 and 13 rIA, the S/V curves of bearings A and B are shown at 44 and 45, respectively, and the amplitude and phase of vibration at the rotation speed of 2882.0 degrees PMl are 52.12 μm and 30.00 μm, respectively. Yes.

Initial bearing insertion, swing width of B 130.99 μs, 104.
This is significantly reduced compared to 29 μm. In addition, the number of rotations is 3
490. The amplitudes of bearings A and B in ORPM are much smaller than the target vibration value of 20 μm, 9.2 μm, respectively.
It is 8.2 μm.

Note that if the initial target value cannot be lowered by - times of balancing, recalculation can be performed using data from the trial test and new initial data from the confirmation test.

[Effects of the Invention] As is clear from the above description, according to the present invention, test conditions and test procedures for performing balancing are input to the display circuit, and vibrations detected by a vibration detector are detected by a separate rotation reference pulse detector and a rotation Human/D conversion operation is started using a rotational reference pulse from a pulse detector, A/D conversion data is sampled and digitized using a rotational pulse, and then the order is analyzed using an FFT processor. Specify multiple types of rotation speeds to be balanced while looking at the S/V curve data created by the 8/V circuit, calculate correction weights at these rotation speeds using the balance calculation circuit, and display them on the display circuit. In addition, by comparing the vibration prediction value using the correction weight with the vibration target value and displaying a comment based on the comparison result, the operation start and sampling of the A/D conversion circuit can be performed using separate rotation reference pulses.
Since it is controlled by the pulse signal of the rotation pulse detector, a digital signal that is completely synchronized with the rotation speed can be obtained, so even if the rotation speed changes rapidly or constantly fluctuates in rotating machines, unbalanced positions can be detected with minimal error. The correction weight can be determined accurately by calculation. In addition, it is possible to specify multiple types of rotation speeds at which unbalance should be corrected on the 8/V curve and simultaneously determine the I correction weight that satisfies the vibration target value. This has the effect that the balancing work can be greatly shortened without having to carry out the balancing work, and in particular, the on-site balancing of rotating bodies such as elastic shafts that have several critical speeds is facilitated. Also,
Since the vibration characteristics of the rotating body can be monitored at the same time using the S/V curve, machine operation and balance work can be performed safely.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of a portable balancing device according to an embodiment of the present invention, FIG. 2 is a diagram showing a rotation reference pulse detector and rotation reference pulses and rotation pulses from the rotation pulse detector, and FIG. FIG. 4 is a perspective view of a disc and a gear, each having a rotation reference position and an angle mark (position);
FIG. 5 is a flowchart showing the balancing procedure in the portable balancing device shown in FIG. 1, and FIGS.
Figure 8 shows the size of the trial weight shown on the display and the mounting position. Figure 1g9 and Figure 10 show the S/ in the trial test shown on the display. A diagram showing the V curve and vibration values, Figure 11 is a diagram showing the size and mounting position of the correction weight shown on the display device, vibration prediction values, and comments. Figures 12 and 13 are confirmation tests with the correction weight installed. 87 shown on the display at
1 is a diagram showing one curve and vibration values. la, lb: vibration detector, 2; amplification circuit, 3; A/D conversion circuit, 4, FPT processor, 5; 8/V times W&
, 6: Memory circuit, 7: 'y'-to circuit, 8; Balance calculation circuit, 9; Display circuit, 10; Comparison circuit, 11;
Rotating reference pulse detector, 12; Rotating pulse zl 口／4 Jutsu 3 flash 4 drawing technique Otsu ni th atsu δ Kanji q flash) - Kenbyo paper 127

Claims (1)

[Claims] 1) A vibration detector that is installed on a bearing that supports the rotating body of a rotating machine and detects vibrations generated by the rotating body, an amplification circuit that amplifies the electrical signal from this vibration detector, and this amplification circuit. An A/D conversion circuit that converts an analog electrical signal from a circuit into a digital electrical signal, and a reference position previously provided on the rotating body to synchronize the sampling and start of this A/D conversion with the rotation of the rotating body. The sampling interval of the rotation reference pulse detector that detects the signal and the A/D conversion circuit is based on one rotation of the rotating body, and is performed at the order multiple of that rotation.
A rotation pulse detector that detects a reference position corresponding to the order multiplied by a rotation pulse detector provided in advance on the rotating body and an order analysis of the digital electric signal of the A/D conversion circuit are used to calculate the level of the signal synchronized with the rotation and the rotation reference pulse as a reference. A fast Fourier transform processor outputs the phase of the signal, and from the data analyzed by this fast Fourier transform processor, only the first-order fundamental component corresponding to the rotation speed of the rotating body is extracted, and the rotation speed and its vibration level are graphed. a gate circuit that controls the start of operation of the A/D conversion circuit by a reference pulse signal from a rotation reference pulse detector; A memory circuit that stores the data of the next fundamental component, and the output data from this memory circuit is used to calculate the amount of unbalance of the rotating body and the position of the unbalance from the reference position of the rotating body, and further based on this calculation result, A balance calculation circuit that predicts a vibration value, a comparison circuit that compares the vibration prediction value from this calculation circuit with a vibration target value to determine whether or not this predicted value reaches the vibration target value, and a comparison circuit that compares the calculation result from the balance calculation circuit. A portable balancing device characterized by comprising a display circuit that displays comparison results from the circuit and further inputs conditions and test procedures necessary for balance calculation.