A method for adjusting dynamic balance of motor rotor

Abstract

The present invention discloses a method for adjusting the dynamic balance of a motor rotor, comprising the following steps: S1, assembling the rotor shaft of the motor rotor on a dynamic balancing device, selecting a left calibration part and a right calibration part at both ends of the rotor body of the motor rotor, and setting a 0 degree position on the left calibration part and the right calibration part; S2, calculating the allowable imbalance degree and allowable imbalance amount of the rotor shaft to obtain the qualified amplitude of the rotor shaft; S3, driving the motor rotor to run and compare the amplitude change curve of the first correction end and the amplitude change curve of the first non-correction end of the rotor shaft through the dynamic balancing device; S4, measuring the left amplitude curve and the right amplitude curve of the rotor shaft under actual operation. The present invention automatically detects the dynamic balance of the motor rotor, and completes the automatic balancing with high precision and high efficiency by adding materials.

Description

Technical Field

[0001] The invention relates to the field of motors, and in particular to a method for adjusting the dynamic balance of a motor rotor. Background Art

[0002] Rotor dynamic balancing is an important and indispensable process in the motor rotor manufacturing process. As the current motor technology has higher and higher requirements for high speed, high precision and low vibration and noise, improving rotor dynamic balancing technology has become a key link in motor manufacturing technology.

[0003] When the motor rotor is dynamically balanced, it is usually relied on to rotate freely and then come to a standstill, with the center of gravity at its lowest end. This method is extremely inefficient and inaccurate, and will waste a lot of time, especially in mass production. The motor rotor balancing machine can accurately find the center of gravity, but it needs to drive the rotor to rotate many times, which still wastes a lot of time. Regardless of the method, after finding the center of gravity, it is necessary to add eccentric blocks or dynamic balancing mud, modify the size and position of the eccentric blocks or dynamic balancing mud many times, and check whether they are adjusted in place many times. The process of using dynamic balancing mud for adjustment is very cumbersome, and it is also necessary to wait for the dynamic balancing mud to solidify, and the production efficiency is not high.

[0004] After the motor has been running for a period of time, due to its own vibration during operation, it is necessary to do dynamic balancing again. In addition, the size and position of the dynamic balancing mud need to be modified again. Sometimes, the original dynamic balancing mud needs to be removed, which is not only inefficient but also wasteful. Summary of the invention

[0005] The invention provides a method for adjusting the dynamic balance of a motor rotor. The invention performs automatic fitting calculation on the dynamic balance of the motor rotor and efficiently completes the dynamic balance of the motor rotor by adding materials.

[0006] The technical solutions to the above technical problems are as follows:

[0007] A method for adjusting the dynamic balance of a motor rotor comprises the following steps:

[0008] S1, assembling the rotor shaft of the motor rotor on the dynamic balancing device, selecting a left calibration part and a right calibration part at both ends of the rotor body of the motor rotor, and setting a 0 degree position on the left calibration part and the right calibration part;

[0009] S2, calculating the allowable unbalance degree and allowable unbalance amount of the rotor shaft to obtain the qualified amplitude of the rotor shaft;

[0010] S3, driving the motor rotor to operate by a dynamic balancing device and performing comparison to obtain an amplitude variation curve of a first correction end and an amplitude variation curve of a first non-correction end of the rotor shaft;

[0011] S4, the amplitude curves on the left and right sides of the rotor shaft during actual operation;

[0012] S5, performing phase fitting on the left amplitude curve in S4 and the amplitude change curve of the first correction end in S3 to obtain the correction amount amplitude change curve of the first correction end, performing phase fitting on the left amplitude curve in S4 and the amplitude change curve of the first non-correction end in S3 to obtain the correction amount amplitude change curve of the first non-correction end;

[0013] S6, after calculating the weight and phase of the material actually added to the left calibration part according to the qualified amplitude of S2, the maximum amplitude of the measured amplitude curve of the left side of the rotor shaft, and the maximum amplitude of the correction amount amplitude change curve of the first correction end, the dynamic balancing device calculates the first left side correction amplitude curve and the first right side correction amplitude curve of the rotor shaft;

[0014] S7, the dynamic balancing device determines whether the maximum amplitude in the first left side correction amplitude curve is qualified. If not, S3-S6 are repeated; if qualified, the dynamic balancing device determines whether the maximum amplitude in the first right side correction amplitude curve is qualified. If qualified, the weight of the actual added material calculated in S6 is added to the phase corresponding to the left calibration part; if the first right side correction amplitude curve is judged to be unqualified, enter S8;

[0015] S8, performing phase fitting on the first right side correction amplitude curve obtained in S6 and the amplitude change curve of the first correction end in S3 to obtain a correction amount amplitude change curve of the second correction end, performing phase fitting on the first right side correction amplitude curve obtained in S6 and the amplitude change curve of the first non-correction end in S3 to obtain a correction amount amplitude change curve of the second non-correction end;

[0016] S9, after calculating the weight and phase of the material actually added to the right calibration part according to the qualified amplitude of S2, the maximum amplitude of the first right side correction amplitude curve, and the maximum amplitude of the correction amount amplitude change curve of the second correction end, the dynamic balancing device calculates the second left side correction amplitude curve and the second right side correction amplitude curve of the rotor shaft;

[0017] S10, the actual weight of the added material calculated according to S6 is added to the phase corresponding to the left calibration part, and the actual weight of the added material calculated according to S9 is added to the phase corresponding to the right calibration part.

[0018] In the present invention, the amplitude variation curves of the motor rotors of the same series are first collected to obtain the amplitude variation curves of the first correction end and the amplitude variation curves of the first non-correction end of the rotor shaft. Then, the left amplitude curve and the right amplitude curve of the rotor shaft are obtained under the actual measurement operation, and the left amplitude curve of the rotor shaft under the actual measurement operation is fitted with the amplitude variation curve of the first correction end to obtain the correction amount amplitude variation curve of the first correction end, and the left amplitude curve of the rotor shaft under the actual measurement operation is fitted with the amplitude variation curve of the first non-correction end to obtain the correction amount amplitude variation curve of the first non-correction end. According to the qualified amplitude calculated initially, the maximum amplitude of the actual measured amplitude curve of the left amplitude of the rotor shaft, and the maximum amplitude of the correction amount amplitude variation curve of the first correction end, the weight and phase of the material (such as balancing mud) actually added in the calibration part are calculated, and the dynamic balancing device calculates the first left correction amplitude curve and the first right correction amplitude curve of the rotor shaft, and judges whether the maximum amplitude of the correction amplitude curve meets the requirements. If it meets the requirements, the material can be added at the specified phase on the corresponding calibration part.

[0019] The present invention accurately knows the specific position of adding the material to be added on the rotor body by fitting the amplitude curve each time, thus avoiding multiple dynamic balancing tests and further avoiding the modification of the weight and position of the dynamically added material, which not only improves efficiency but also saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the coordination diagram between the motor rotor and the dynamic balancing equipment.

[0021] Figure 2 This is a schematic diagram of the first left amplitude curve during low-speed operation.

[0022] Figure 3 This is a schematic diagram of the first right amplitude curve during low-speed operation.

[0023] Figure 4 This is a schematic diagram of the second left amplitude curve during low-speed operation.

[0024] Figure 5 This is a schematic diagram of the second right amplitude curve when running at low speed.

[0025] Figure 6 This is a schematic diagram of the primary amplitude change curve at the correction end.

[0026] Figure 7 This is a schematic diagram of the primary amplitude change curve at the non-correction end.

[0027] Figure 8 This is a schematic diagram of the third left amplitude curve during low-speed operation.

[0028] Fig. 9 This is a schematic diagram of the third right amplitude curve when running at low speed.

[0029] Fig.10 It is a schematic diagram of the secondary amplitude change curve at the non-correction end.

[0030] Fig.11 It is a schematic diagram of the secondary amplitude change curve at the correction end.

[0031] Fig.12 It is a schematic diagram of the amplitude variation curve of the first correction end under low-speed operation.

[0032] Fig.13 It is a schematic diagram of the amplitude variation curve of the first non-correction end under low-speed operation.

[0033] Fig.14 It is a schematic diagram of the amplitude variation curve of the second correction end under high-speed operation.

[0034] Fig.15 It is a schematic diagram of the amplitude variation curve of the second non-correction end under high-speed operation.

[0035] Fig.16 This is a schematic diagram of the amplitude curve of the left side of the rotor shaft under low-speed operation before correction.

[0036] Fig.17 This is a schematic diagram of the amplitude curve of the right side of the rotor shaft under low-speed operation before correction.

[0037] Fig.18 For Fig.12 The diagram shows a variation curve extracted from the amplitude variation curve of the first correction end.

[0038] Fig.19 Schematic diagram of the correction amount amplitude change curve of the first correction end.

[0039] Fig. 20 Schematic diagram of the correction amount amplitude change curve of the first non-correction end.

[0040] Fig.21 The first left side corrected amplitude curve diagram after low speed calibration is calculated for the dynamic balancing device according to relevant data.

[0041] Fig. 22 The first right side corrected amplitude curve diagram after low speed calibration is calculated for the dynamic balancing device according to relevant data.

[0042] Fig.23 Schematic diagram of the correction amount amplitude change curve of the second correction end.

[0043] Fig.24 Schematic diagram of the correction amount amplitude change curve of the second non-correction end.

[0044] Fig.25The second left side corrected amplitude curve diagram after low speed calibration is calculated for the dynamic balancing device according to relevant data.

[0045] Fig.26 The second right side corrected amplitude curve diagram after low speed calibration is calculated for the dynamic balancing equipment according to relevant data.

[0046] Fig. 27 This is the corrected amplitude curve of the left side of the rotor shaft under low-speed operation.

[0047] Fig.28 This is the corrected amplitude curve of the left side of the rotor shaft under low-speed operation.

[0048] Fig.29 This is a schematic diagram of the amplitude curve of the left side of the rotor shaft under high-speed operation before correction.

[0049] Fig.30 This is a schematic diagram of the amplitude curve of the right side of the rotor shaft under high-speed operation before correction.

[0050] Fig.31 Schematic diagram of the correction amount amplitude change curve of the third correction end.

[0051] Fig.32 Schematic diagram of the correction amount amplitude change curve of the third non-correction end.

[0052] Fig.33 The third left side corrected amplitude curve is calculated for the dynamic balancing equipment according to relevant data after high-speed calibration.

[0053] Fig.34 The third right side corrected amplitude curve is calculated for the dynamic balancing equipment according to relevant data after high-speed calibration.

[0054] Fig.35 Schematic diagram of the correction amount amplitude variation curve of the fourth correction end.

[0055] Fig.36 Schematic diagram of the correction amount amplitude change curve of the fourth non-correction end.

[0056] Fig.37 The fourth left-side corrected amplitude curve is calculated for the dynamic balancing device after high-speed calibration based on relevant data.

[0057] Fig.38 The fourth right side corrected amplitude curve diagram after high-speed calibration is calculated for the dynamic balancing equipment according to relevant data.

[0058] Fig.39 This is the corrected amplitude curve of the left side of the rotor shaft under high-speed operation.

[0059] Fig.40This is the corrected amplitude curve of the left side of the rotor shaft under high-speed operation.

[0060] Fig.41 The left amplitude curve is the re-measurement of low-speed operation.

[0061] Fig.42 The right amplitude curve is the re-measurement of low-speed operation. DETAILED DESCRIPTION

[0062] A method for adjusting the dynamic balance of a motor rotor according to the present invention comprises the following steps:

[0063] S1, assemble the rotor shaft 1a of the motor rotor on the dynamic balancing device (such as Figure 1 As shown in FIG. 1 ), the dynamic balancing device belongs to the prior art. The controller in the dynamic balancing device and the driving mechanism connected to the rotor shaft 1a are Figure 1 Not shown.

[0064] like Figure 1 As shown, the specific implementation process of S1 is: select a first portion on the rotor shaft 1a as the first measuring surface 2, select a second portion on the rotor shaft 1a as the second measuring surface 3, cooperate the first vibration sensor 4 with the first measuring surface 2 to collect the left amplitude of the rotor shaft 1a during operation, and cooperate the second vibration sensor 5 with the second measuring surface 3 to collect the right amplitude of the rotor shaft 1a during operation.

[0065] In the initial static state, a first reflective sheet 6 is attached to the rotor shaft 1a at a position 180 degrees relative to the first vibration sensor 4, and a second reflective sheet 7 is attached to the rotor shaft 1a at a position 180 degrees relative to the second vibration sensor 5. The first photoelectric sensor 8 is matched with the first reflective sheet 6 and the second photoelectric sensor 9 is matched with the second reflective sheet 7 to collect the phase of the rotor shaft 1a during operation. After the left calibration part 10 and the right calibration part 11 are respectively set on the circumferential surfaces of the rotor body 1b of the motor rotor, a 0-degree position is set on the left calibration part 10 and the right calibration part 11. The 0-degree position on the left calibration part 10 is located on the same straight line as the center of the first reflective sheet 6, the 0-degree position on the right calibration part 11, and the center of the second reflective sheet 7. When adding materials (such as balancing mud) to the circumferential positions determined by the left and right calibration parts later, the 0-degree position is used as the starting position.

[0066] S2, calculating the allowable unbalance degree and allowable unbalance amount of the rotor shaft to obtain the qualified amplitude of the rotor shaft 1a.

[0067] The calculation formula for the allowable unbalance of the rotor shaft is:

[0068]

[0069] In the above formula, Ep is the allowable imbalance of the rotor shaft (unit: μm), G is the balancing accuracy grade (for example, if the grade is G1, then G is 1), n ​​is the operating speed of the motor rotor (unit: r / min); S is the coefficient corresponding to different operating speeds, and q is the correction coefficient considering errors such as equipment.

[0070] The calculation formula for the allowable unbalance of the rotor shaft is:

[0071]

[0072] In the above formula, Mper is the allowable unbalance of the rotor shaft (unit: g); M is the weight of the motor rotor itself (unit: kg); and r is the correction radius of the motor rotor (unit: mm).

[0073] In this embodiment, the operation of the motor rotor is divided into low-speed operation and high-speed operation, that is, to ensure that the rotor runs more stably, the dynamic balance adjustment is divided into low-speed dynamic balance and high-speed dynamic balance. The coefficient S is 1 for high-speed dynamic balancing and 0.2 for low-speed dynamic balancing. The balancing accuracy level to be achieved in the present invention is G1, so the value of G is 1. Assuming that the operating speed n of the motor rotor is 1000r / min, the weight M of the motor rotor itself is 0.2kg, and the correction radius r of the motor rotor is 10mm, the allowable imbalance and allowable imbalance amount of the rotor shaft 1a when running at low speed, as well as the allowable imbalance and allowable imbalance amount of the rotor shaft 1a when running at high speed are calculated below.

[0074] The allowable unbalance of the rotor shaft when running at low speed is Ep = 1 × 1000 ÷ (1000 × 0.2 ÷ 10) × 0.8 = 40 μm

[0075] When running at low speed, the allowable unbalance of the rotor shaft is Mper=0.2×1×60÷(2×3.14×10×1000×0.2)×1000=0.955g≈1.0g.

[0076] The allowable unbalance of the rotor shaft during high-speed operation is Ep = 1 × 1000 ÷ (1000 ÷ 10) × 0.8 = 8 μm

[0077] When running at high speed, the allowable unbalance of the rotor shaft is Mper=0.2×1×60÷(2×3.14×10×1000)×1000=0.19g≈0.2g.

[0078] Next, follow steps S3 to S10 to perform dynamic balancing on the motor rotor running at low speed (200r / min).

[0079] S3, the motor rotor is driven to run at a low speed by the dynamic balancing equipment and compared to obtain the amplitude change curve of the first correction end and the amplitude change curve of the first non-correction end of the rotor shaft 1a. S3 is the initial process of collecting the following data curves for the same series of rotors.

[0080] The steps of obtaining the amplitude variation curve of the first correction end and the amplitude variation curve of the first non-correction end of the rotor shaft 1a are as follows:

[0081] S31, the motor rotor is driven by the dynamic balancing device to run at a low speed to obtain the first left amplitude curve and the first right amplitude curve of the rotor shaft 1a; during the operation Figure 1 The first vibration sensor 4 shown in the figure outputs the amplitude of the left side of the rotor shaft 1a, the second vibration sensor 5 outputs the amplitude of the right side of the rotor shaft 1a, the first photoelectric sensor 8 outputs the phase of the left side of the rotor shaft 1a, and the second photoelectric sensor 9 outputs the phase of the right side of the rotor shaft 1a. According to the relationship between the output amplitude and phase, the amplitude curves of the left and right sides of the rotor shaft 1a are obtained respectively. The amplitude curves of 720 degrees are respectively adopted from the amplitude curves of the left and right sides of the rotor shaft 1a, so as to obtain the first left amplitude curve under low speed operation (such as Figure 2 ) and the first right amplitude curve (as shown Figure 3 The horizontal direction in the figure represents the phase position (in degrees), and the vertical direction represents the amplitude (in μm).

[0082] S32, on the basis of S31, material is added at the 0 degree position on the left calibration part 10 according to the percentage weight of the allowable unbalance of the rotor shaft. In this embodiment, material is added at 20% of the allowable unbalance of the rotor shaft. Since the allowable unbalance Mper of the rotor shaft is 1.0g when running at low speed, the added material at the 0 degree position on the left calibration part 10 is 0.2g. The specific added materials and means are prior art and will not be elaborated here.

[0083] After adding the material, the motor rotor is driven to run at a low speed by the dynamic balancing device to obtain the second left amplitude curve and the second right amplitude curve of the rotor shaft 1a. In this embodiment, the second left amplitude curve shown is a curve obtained by extracting two cycles (720°) (such as Figure 4 As shown in the figure, the second right amplitude curve is the curve of extracting two cycles (720°) (as shown in the figure Figure 5 as shown).

[0084] S33, comparing the first left amplitude curve with the second left amplitude curve and subtracting them to obtain a correction end primary amplitude change curve, that is, Figure 2 The first left amplitude curve shown is Figure 4 The first amplitude change curve of the correction end is obtained by comparing and subtracting the second left amplitude curve shown in FIG. Figure 6The first right amplitude curve is compared with the second right amplitude curve and then subtracted to obtain the non-correction end primary amplitude change curve; Figure 3 The first right amplitude curve shown is Figure 4 The first amplitude change curve of the correction end is obtained by comparing and subtracting the second right amplitude curve shown in FIG. Figure 7 shown.

[0085] Since the above-mentioned S32 only adds material to the left calibration part 10, and no increase or decrease operation is performed on the right calibration part 11, at this time, the curve obtained by comparing and subtracting the first left amplitude curve from the second left amplitude curve is called the correction end primary amplitude change curve, and the curve obtained by comparing and subtracting the first right amplitude curve from the second right amplitude curve is called the non-correction end primary amplitude change curve.

[0086] S34, based on S32, material is added at the 0 degree position on the right calibration part 11 according to the percentage weight of the allowable unbalance of the rotor shaft. In this embodiment, material is added at 20% of the allowable unbalance of the rotor shaft. Since the allowable unbalance Mper of the rotor shaft is 1.0g when running at low speed, the added material at the 0 degree position on the right calibration part 11 is 0.2g.

[0087] After adding the material, the motor rotor is driven to run at a low speed by the dynamic balancing device to obtain the third left amplitude curve and the third right amplitude curve of the rotor shaft 1a; in this embodiment, the third left amplitude curve shown is a curve obtained by extracting two cycles (720°) (such as Figure 8 As shown in the figure, the third right amplitude curve is the curve of extracting two cycles (720°) (as shown in the figure Fig. 9 as shown).

[0088] S35, comparing the second right amplitude curve with the third right amplitude curve and subtracting them to obtain a correction end secondary amplitude change curve, that is, Figure 5 The second right amplitude curve shown is Fig. 9 The third right amplitude curve shown in FIG. 1 is compared and subtracted to obtain the secondary amplitude change curve of the correction end. The secondary amplitude change curve of the correction end is as shown in FIG. Fig.11 The second left amplitude curve is compared with the third left amplitude curve and then subtracted to obtain the secondary amplitude change curve of the non-corrected end, that is, Figure 4 The second left amplitude curve shown is Figure 8 The third left amplitude curve shown in FIG. 1 is compared and subtracted to obtain the secondary amplitude change curve of the non-correction end. The secondary amplitude change curve of the non-correction end is as follows: Fig.10 shown.

[0089] Since the above-mentioned S34 adds material to the right calibration part 11, and the right calibration part 10 does not perform any increase or decrease operation, at this time, the curve obtained by comparing and subtracting the second right amplitude curve from the third right amplitude curve is called the correction end secondary amplitude change curve, and the curve obtained by comparing and subtracting the second left amplitude curve from the third left amplitude curve is called the non-correction end secondary amplitude change curve.

[0090] S36, after comparing and correcting the multiple groups of correction end primary amplitude change curves and correction end secondary amplitude change curves, an amplitude change curve of the first correction end of the rotor shaft 1a during low-speed operation (such as Fig.12 As shown in FIG. 1 ), the amplitude variation curve of the first non-correction end of the rotor shaft 1a during low-speed operation is obtained by comparing and correcting multiple groups of non-correction end primary amplitude variation curves and non-correction end secondary amplitude variation curves (as shown in FIG. 1 ). Fig.13 The contrast correction is to take the average value of the curve.

[0091] The motor rotor speed is adjusted to high speed (speed is 1000r / min) and the amplitude variation curve of the second correction end at high speed operation is obtained according to the steps S31 to S36. Fig.14 ), and a schematic diagram of the amplitude variation curve of the second non-correction end (as shown Fig.15 as shown).

[0092] According to the above calculation results: When the rotor shaft is running at low speed, the allowable unbalance Ep=40μm, and the allowable unbalance Mper of the rotor shaft is about 1.0g. After being distributed to two symmetrical surfaces, the allowable unbalance of the rotor shaft on each surface at low speed is about 0.5g. When the rotor shaft is running at high speed, the allowable unbalance Ep=8μm, and the allowable unbalance Mper of the rotor shaft is about 0.2g. The allowable unbalance of the rotor shaft on each surface at high speed is about 0.1g.

[0093] According to the above, the weight of each standard correction material added during correction is calculated as 20%, then: the weight of each standard correction material during correction under low-speed operation is 0.5×20%=0.1g, and the weight of each standard correction material during correction under high-speed operation is 0.1×20%=0.02g.

[0094] S4, measured amplitude curve of the left side of the rotor shaft 1a under low speed operation (such as Fig.16 ) and the amplitude curve on the right (as shown Fig.17 As shown in the figure). It can be seen from the measured curve that the maximum amplitudes on both sides of the rotor shaft 1a exceed the 40μm required at low speed.

[0095] S5, phase fitting is performed on the left amplitude curve in S4 and the amplitude change curve of the first correction end in S3 to obtain the correction amount amplitude change curve of the first correction end (such as Fig.19 ), the amplitude curve on the left side of S4 is phase-fitted with the amplitude change curve of the first non-corrected end in S3 to obtain the correction amount amplitude change curve of the first non-corrected end ( Fig. 20 ).

[0096] The process of obtaining the correction amount amplitude variation curve of the first correction end and the correction amount amplitude variation curve of the first non-correction end in S5 is:

[0097] S51, determining the phase corresponding to the maximum amplitude in the left amplitude curve in S4.

[0098] S52, intercepting the curve containing the phase corresponding to the maximum amplitude in S51 from the amplitude change curve of the first correction end in S3, converting the phase of the curve into a corresponding relationship with the amplitude curve of the left side of the rotor shaft 1a under the actual low-speed operation, and obtaining the correction amount amplitude change curve of the first correction end.

[0099] S53, intercepting a curve including a phase corresponding to the maximum amplitude in S53 from the amplitude variation curve of the first non-correction end in S3, converting the phase of the curve into a corresponding relationship with the amplitude curve of the right side of the rotor shaft 1a under the actual low-speed operation, and obtaining the correction amount amplitude variation curve of the first non-correction end.

[0100] Combined with Fig.16 It can be seen that the maximum amplitude of the amplitude curve on the left side of the rotor shaft 1a under low-speed operation corresponds to a phase of 220 degrees. Fig.12 The amplitude variation curve of the first correction end shown in FIG. 1 is intercepted to include the variation curve of the 220 degree position. Fig.18 As shown, the period of the curve is one period, and the phase of the curve is converted into the measured Fig.16 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the first correction end (such as Fig.19 ).

[0101] According to the above process from Fig.13 The corresponding phase change curve is intercepted from the amplitude change curve of the first non-corrected end shown in FIG. 1 , and the phase of the curve is converted into the phase of the measured Fig.16 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the first non-correction end (such as Fig. 20 ).

[0102] S6, after calculating the weight and phase of the material actually added to the left calibration part 10 based on the qualified amplitude of S2, the maximum amplitude of the amplitude curve of the left side of the rotor shaft 1a, and the maximum amplitude of the correction amount amplitude change curve of the first correction end, the dynamic balancing device calculates the first left side correction amplitude curve of the rotor shaft 1a (such as Fig.21 ) and the first right side modified amplitude curve (such as Fig. 22 ).

[0103] like Fig.16 The maximum amplitude shown is 82 μm, Fig.19 The maximum amplitude of the correction amplitude change curve of the first correction end shown is 9μm. Since the required qualified amplitude is 40μm, the calculation formula for the number of standard correction weights added during low-speed correction is: (82-40) / 9≈5. In order to ensure calibration stability, 5+1=6 standard correction weights are usually taken, that is, 6×0.1g=0.6g, where 0.1g is the weight of each standard correction material during correction under low-speed operation calculated above. In this way, 0.6g of material weight needs to be added at the 220-degree position on the left calibration part 10.

[0104] After calculating and adding 0.6g weight at the 220 degree position on the left calibration part 10, the dynamic balancing device then calculates the first left side correction amplitude curve after calibration (such as Fig.21 ) and the first right side modified amplitude curve (such as Fig. 22 ).

[0105] S7, the dynamic balancing device determines whether the maximum amplitude in the first left side correction amplitude curve is qualified (such as Fig.21 ), if not qualified, repeat S3-S6; if the maximum amplitude in the first left side correction amplitude curve is qualified, the dynamic balancing device determines whether the maximum amplitude in the first right side correction amplitude curve is qualified (such as Fig. 22 ); if qualified, then the weight of the actual added material calculated in S6 is added to the corresponding phase of the left calibration part 10 to complete the dynamic low-speed balance adjustment; if the first right side correction amplitude curve is judged to be unqualified, enter S8.

[0106] Depend on Fig.21 It can be seen that the maximum amplitude in the first left side correction amplitude curve is less than the upper limit of the qualified amplitude requirement (40 μm), and the maximum amplitude in the first right side correction amplitude exceeds the upper limit of the qualified amplitude requirement (40 μm). Therefore, the low-speed dynamic balancing adjustment in the embodiment is not completely qualified, and it is necessary to enter S8 for further adjustment.

[0107] S8, phase-fit the first right-side corrected amplitude curve obtained in S6 with the amplitude change curve of the first correction end in S3 to obtain the correction amount amplitude change curve of the second correction end, and phase-fit the first right-side corrected amplitude curve obtained with the amplitude change curve of the first non-correction end in S3 to obtain the correction amount amplitude change curve of the second non-correction end.

[0108] For S8, specifically, combined with Fig. 22 It can be seen that the maximum amplitude of the first right side corrected amplitude curve is 87 μm, which corresponds to a phase of 190 degrees. Fig.12The amplitude variation curve of the first correction end shown in FIG. 1 is intercepted to include the variation curve of the 190 degree position. The period of the curve is one period. The phase of the curve is converted into Fig. 22 The correction amount amplitude change curve of the second correction end is obtained by the corresponding relationship (such as Fig.23 ).

[0109] According to the above process from Fig.13 The amplitude variation curve of the first non-corrected end shown in FIG. 1 is intercepted to include the variation curve of the 190 degree position, and the phase of the curve is converted into Fig. 22 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the second non-correction end (such as Fig.24 ).

[0110] S9, based on the qualified amplitude of S2 and the maximum amplitude of the first right side modified amplitude curve ( Fig. 22 ), the maximum amplitude of the correction amount amplitude change curve of the second correction end, after calculating the weight and phase of the material actually added to the right calibration part 11, such as Fig. 22 As shown in FIG. 1 , the maximum amplitude of the first right side modified amplitude curve is 87 μm. Fig.23 The maximum amplitude of the correction amplitude change curve of the second correction end shown is 9μm, and the qualified amplitude is 40μm. The calculation formula for the number of standard correction weights added during low-speed correction is (87-40) / 9≈5. To ensure calibration stability, 5+1=6 standard correction weights are usually taken, that is, 6×0.1g=0.6g. In this way, 0.6g of material needs to be added at the 190-degree position on the right calibration part 11.

[0111] After calculating that 0.6g of material is added at the 190-degree position on the right calibration portion 11, the dynamic balancing device then calculates the second left side correction amplitude curve of the rotor shaft 1a after calibration (such as Fig.25 ) and the second right side modified amplitude curve (such as Fig.26 ).

[0112] S10, the dynamic balancing device determines whether the second right side corrected amplitude curve is qualified, if not, repeat S8-S9; if the second right side corrected amplitude curve is qualified, the dynamic balancing device determines whether the second left side corrected amplitude curve is qualified, if qualified, the weight of the actual added material calculated according to S6 is added to the phase corresponding to the left calibration part 10, and the weight of the actual added material calculated according to S9 is added to the phase corresponding to the right calibration part 11, and then the low-speed dynamic balancing adjustment is completed.

[0113] In this embodiment, specifically, according to Fig.25 It can be seen that the maximum amplitude in the second left-hand modified amplitude curve is at the upper limit of the qualified amplitude requirement. Fig.26It can be seen that the maximum amplitude in the second right side correction amplitude is at the upper limit of the qualified amplitude requirement, that is, the maximum amplitude in the second left side correction amplitude curve and the second right side correction amplitude curve are both less than 40 μm, and thus the motor rotor theoretically meets the requirements through the above method. Therefore, 0.6 g of material is actually added at 220 degrees of the left calibration part 10 on the rotor body 1b, and 0.6 g of material is actually added at 190 degrees of the right calibration part 11 on the rotor body 1b.

[0114] After the addition is completed, the dynamic balancing equipment drives the motor rotor to run at a low speed. The rotor shaft 1a is measured by the dynamic balancing equipment. The amplitude curve of the left side of the rotor shaft under low-speed operation is measured after correction. Fig. 27 As shown in the figure, the amplitude curve of the right side of the rotor shaft under low-speed operation after correction is as follows: Fig.28 As shown, through Fig. 27 and Fig.28 It can be directly concluded that after correction, the dynamic balance of the rotor meets the requirements when running at low speed.

[0115] If the second left side corrected amplitude curve is judged to be unqualified during low-speed operation after correction, the process returns to S6 to repeat the detection and correction until the requirements are met.

[0116] Next, follow steps S3 to S10 to perform dynamic balancing on the motor rotor running at high speed (speed of 1000r / min). Follow steps S31 to S36 above to obtain the amplitude variation curve of the second correction end under high speed operation (e.g. Fig.14 ), and a schematic diagram of the amplitude variation curve of the second non-correction end (as shown Fig.15 as shown).

[0117] The amplitude curve of the left side of the rotor shaft 1a under high-speed operation was measured (such as Fig.29 ) and the amplitude curve on the right (as shown Fig.30 As shown). It can be seen from the measured curve that the maximum amplitudes on both sides of the rotor shaft 1a exceed the upper limit of 8μm required by the calculation at high speed.

[0118] Combined with Fig.29 It can be seen that the maximum amplitude of the amplitude curve on the left side of the rotor shaft 1a under high-speed operation corresponds to a phase of 60 degrees. Fig.14 The amplitude variation curve of the second correction end shown in FIG. Fig.31 As shown, the period of the curve is one period, and the phase of the curve is converted into the measured Fig.29 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the third correction end (such as Fig.31 ).

[0119] According to the above process from Fig.15The corresponding phase change curve is intercepted from the amplitude change curve of the second non-corrected end shown in FIG. 1 , and the phase of the curve is converted into the phase of the measured Fig.29 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the third non-correction end (such as Fig.32 ).

[0120] like Fig.29 The maximum amplitude of the amplitude curve on the left side of the rotor shaft 1a under high-speed operation is 10.5 μm. Fig.31 The maximum amplitude of the correction amount amplitude change curve of the third correction end shown is 4.5μm. Since the qualified amplitude required under high-speed operation is 8μm, the calculation formula for the number of standard correction weights to be added during high-speed correction is: (10.5-4.5) / 8≈1, thereby calculating that 1 standard correction material weight needs to be added during correction under high-speed operation, that is, 0.02g of material weight needs to be added at the 60-degree position on the left calibration part 10.

[0121] After the dynamic balancing device calculates that a 0.02g weight is added to the 60 degree position on the left calibration part 10, the dynamic balancing device then calculates the third left side correction amplitude curve after calibration (such as Fig.33 ) and the third right side modified amplitude curve (such as Fig.34 ).

[0122] Depend on Fig.33 It can be seen that the maximum amplitude in the third left side correction amplitude curve is less than the upper limit of the qualified amplitude requirement (8μm), and the maximum amplitude in the third right side correction amplitude exceeds the upper limit of the qualified amplitude requirement (8μm). Therefore, the high-speed dynamic balancing adjustment in this embodiment is not completely qualified and needs to be further adjusted.

[0123] Combined with Fig.34 It can be seen that the maximum amplitude of the third right side corrected amplitude curve is 9.1 μm, which corresponds to a phase of 190 degrees. Fig.14 The amplitude change curve of the second correction end shown in FIG. 1 is a curve including a change of 190 degrees. The period of the curve is one period. The phase of the curve is converted into Fig.34 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the fourth correction end (such as Fig.35 ).

[0124] According to the above process from Fig.15 The amplitude variation curve of the second non-corrected end shown in FIG. 1 is intercepted to include the variation curve of the 190 degree position, and the phase of the curve is converted into Fig.34 The corresponding relationship is obtained by obtaining the correction amount amplitude change curve of the fourth non-correction end (such as Fig.36 ).

[0125] like Fig.34 As shown in FIG. 1 , the maximum amplitude of the third right side modified amplitude curve is 9.1 μm. Fig.35 The maximum amplitude of the correction amount amplitude change curve of the fourth correction end shown is 4.5μm, the qualified amplitude requirement is 8μm, and the calculation formula for the number of standard correction weights added during high-speed correction is (9.1-4.5) / 8≈1, thereby calculating that 1 standard correction material weight needs to be added during correction under high-speed operation, that is, 0.02g of material weight needs to be added at the 190-degree position on the right calibration part 11.

[0126] After calculating the addition of 0.02g of material at the 190-degree position on the right calibration part 11, the dynamic balancing device then calculates the fourth left-side corrected amplitude curve of the rotor shaft 1a after calibration (such as Fig.37 ) and the fourth right side modified amplitude curve (such as Fig.38 ).

[0127] In this embodiment, according to Fig.37 It can be seen that the maximum amplitude in the fourth left-hand corrected amplitude curve is less than the upper limit of the qualified amplitude requirement (8μm). Fig.38 It can be seen that the maximum amplitude in the fourth right side correction amplitude is less than the upper limit of the qualified amplitude requirement (8μm), that is, the maximum amplitudes in the fourth left side correction amplitude curve and the fourth right side correction amplitude curve are both less than 8μm, and thus the motor rotor theoretically meets the requirements through the above method. Thus, 0.02g of material is actually added at 60 degrees on the left calibration part 10 of the rotor body 1b, and 0.02g of material is actually added at 190 degrees on the right calibration part 11 of the rotor body 1b.

[0128] After the addition is completed, the dynamic balancing equipment drives the motor rotor to run at high speed (1000r / min). The rotor shaft 1a is measured by the dynamic balancing equipment. After correction, the amplitude curve of the left side of the rotor shaft 1a under high-speed operation is as follows: Fig.39 As shown in the figure, the amplitude curve of the rotor shaft on the right side under high-speed operation after correction is as follows: Fig.40 As shown, through Fig.39 and Fig.40 It can be directly concluded that after correction, the dynamic balance of the electric rotor also meets the requirements when running at high speed.

[0129] After the high-speed dynamic balancing test is completed, the weight and center of the motor rotor have changed, so the dynamic balancing amplitude is re-measured at a low speed. The amplitude curves of the re-measured amplitudes on the left and right sides are as follows: Fig.41 and Fig.42 As shown, through Fig.41 and 42 It can be seen that the requirements are met.

Claims

1. A method for adjusting the dynamic balance of a motor rotor, characterized in that: The following steps are involved: S1, assembling a rotor shaft (1a) of a motor rotor on a dynamic balancing device, selecting a left calibration portion (10) and a right calibration portion (11) at both ends of a rotor body (1b) of the motor rotor, and setting a 0 degree position on the left calibration portion (10) and the right calibration portion (11); S2, calculating the allowable unbalance degree and allowable unbalance amount of the rotor shaft to obtain the qualified amplitude of the rotor shaft (1a); S3, driving the motor rotor to operate by means of a dynamic balancing device and performing comparison to obtain an amplitude variation curve of a first correction end and an amplitude variation curve of a first non-correction end of the rotor shaft (1a); S4, the left and right amplitude curves of the rotor shaft (1a) under actual operation; S5, performing phase fitting on the left amplitude curve in S4 and the amplitude change curve of the first correction end in S3 to obtain the correction amount amplitude change curve of the first correction end, performing phase fitting on the left amplitude curve in S4 and the amplitude change curve of the first non-correction end in S3 to obtain the correction amount amplitude change curve of the first non-correction end; S6, after calculating the weight and phase of the material actually added to the left calibration portion (10) based on the qualified amplitude of S2, the maximum amplitude of the amplitude curve of the left side of the rotor shaft (1a) measured, and the maximum amplitude of the correction amount amplitude change curve of the first correction end, the dynamic balancing device calculates a first left side correction amplitude curve and a first right side correction amplitude curve of the rotor shaft (1a); S7, the dynamic balancing device determines whether the maximum amplitude in the first left-side corrected amplitude curve is qualified. If not, S3-S6 are repeated; if qualified, the dynamic balancing device determines whether the maximum amplitude in the first right-side corrected amplitude curve is qualified. If qualified, the weight of the actual added material calculated in S6 is added to the phase corresponding to the left calibration part (10); if the first right-side corrected amplitude curve is judged to be unqualified, enter S8; S8, performing phase fitting on the first right side correction amplitude curve obtained in S6 and the amplitude change curve of the first correction end in S3 to obtain a correction amount amplitude change curve of the second correction end, performing phase fitting on the first right side correction amplitude curve obtained in S6 and the amplitude change curve of the first non-correction end in S3 to obtain a correction amount amplitude change curve of the second non-correction end; S9, after calculating the weight and phase of the material actually added to the right calibration part (11) based on the qualified amplitude of S2, the maximum amplitude of the first right-side correction amplitude curve, and the maximum amplitude of the correction amount amplitude change curve at the second correction end, the dynamic balancing device calculates a second left-side correction amplitude curve and a second right-side correction amplitude curve of the rotor shaft (1a); S10, the actual weight of the added material calculated according to S6 is added to the phase corresponding to the left calibration part (10), and the actual weight of the added material calculated according to S9 is added to the phase corresponding to the right calibration part (11).

2. A motor rotor dynamic balance adjustment method according to claim 1, characterized in that: The calculation formula for the allowable unbalance of the rotor shaft is: In the above formula, Ep is the allowable imbalance of the rotor shaft, G is the balancing accuracy level, n is the operating speed of the motor rotor; S is the coefficient corresponding to different operating speeds, and q is the correction coefficient considering equipment errors; The calculation formula for the allowable unbalance of the rotor shaft is: In the above formula, Mper is the allowable unbalance of the rotor shaft; M is the weight of the motor rotor itself; and r is the correction radius of the motor rotor.

3. A motor rotor dynamic balance adjustment method according to claim 1, characterized in that: The motor rotor operation is divided into low-speed operation and high-speed operation, and the qualified amplitude in S2 is divided into a low-speed operation qualified amplitude and a high-speed operation qualified amplitude. According to steps S3 to S10, the motor rotor running at low speed is dynamically balanced, and the motor rotor running at high speed is dynamically balanced.

4. A motor rotor dynamic balance adjustment method according to any one of claims 1 to 3, characterized in that: In S3, the steps of obtaining the amplitude variation curve of the first correction end and the amplitude variation curve of the first non-correction end of the rotor shaft (1a) are as follows: S31, obtaining a first left amplitude curve and a first right amplitude curve of the rotor shaft (1a) after the motor rotor is driven by a dynamic balancing device; S32, based on S31, adding material at the 0 degree position on the left calibration part (10) according to the weight percentage of the allowable unbalance amount of the rotor shaft, and driving the motor rotor to run through the dynamic balancing device to obtain a second left amplitude curve and a second right amplitude curve of the rotor shaft (1a); S33, comparing the first left amplitude curve with the second left amplitude curve and subtracting them to obtain a correction end primary amplitude change curve, and comparing the first right amplitude curve with the second right amplitude curve and subtracting them to obtain a non-correction end primary amplitude change curve; S34, based on S32, adding material at the 0 degree position on the right calibration part (11) according to the weight percentage of the allowable unbalance amount of the rotor shaft, and driving the motor rotor to run through the dynamic balancing device to obtain a third left amplitude curve and a third right amplitude curve of the rotor shaft (1a); S35, comparing and subtracting the second right amplitude curve from the third right amplitude curve to obtain a correction end secondary amplitude change curve, and comparing and subtracting the second left amplitude curve from the third left amplitude curve to obtain a non-correction end secondary amplitude change curve; S36, comparing and correcting multiple groups of correction end primary amplitude change curves and correction end secondary amplitude change curves to obtain an amplitude change curve of the first correction end of the rotor shaft (1a), and comparing and correcting multiple groups of non-correction end primary amplitude change curves and non-correction end secondary amplitude change curves to obtain an amplitude change curve of the first non-correction end of the rotor shaft (1a).

5. A motor rotor dynamic balance adjustment method according to claim 4, characterized in that: In S32 and S34, material is added according to 20% of the allowable unbalance of the rotor shaft.

6. A motor rotor dynamic balance adjustment method according to claim 4, characterized in that: In S31, S32, and S34, two periodic curves are respectively extracted from the curve generated after the rotor shaft (1a) is obtained after the dynamic balancing device drives the motor rotor to run, and a first left amplitude curve and a first right amplitude curve, a second left amplitude curve and a second right amplitude curve, and a third left amplitude curve and a third right amplitude curve are respectively obtained.

7. A motor rotor dynamic balance adjustment method according to claim 1, characterized in that: The process of obtaining the correction amount amplitude variation curve of the first correction end and the correction amount amplitude variation curve of the first non-correction end in S5 is: S51, determining the phase corresponding to the maximum amplitude in the left amplitude curve in S4; S52, intercepting a curve including a phase corresponding to the maximum amplitude in S51 from the amplitude variation curve of the first correction end in S3, converting the phase of the curve into a corresponding relationship with the amplitude curve of the left side of the actually measured rotor shaft (1a), and obtaining a correction amount amplitude variation curve of the first correction end; S53, extracting a curve including the phase corresponding to the maximum amplitude in S51 from the amplitude variation curve of the first non-correction end in S3, converting the phase of the curve into a corresponding relationship with the amplitude curve of the right side of the actually measured rotor shaft (1a), and obtaining the correction amount amplitude variation curve of the first non-correction end.

8. The method for adjusting the dynamic balance of a motor rotor according to claim 1, characterized in that: In S10, before actually adding material to the phases corresponding to the left calibration part (10) and the right calibration part (11), the dynamic balancing device first determines whether the second right corrected amplitude curve is qualified. If not, S8-S9 are repeated; if the second right corrected amplitude curve is qualified, the dynamic balancing device determines whether the second left corrected amplitude curve is qualified. If qualified, the weight of the actual added material calculated in S6 is added to the phase corresponding to the left calibration part (10), and the weight of the actual added material calculated in S9 is added to the phase corresponding to the right calibration part (11).

9. A motor rotor dynamic balance adjustment method according to claim 8, characterized in that: In S10, if the second left-side corrected amplitude curve is judged to be unqualified, the process returns to S6.

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