Integral on-site dynamic balancing method for multi-support grinding tool spindles

Abstract

This invention discloses an integral on-site dynamic balancing method for multi-support grinding wheel spindles, specifically implemented according to the following steps: Step 1, pre-balancing of the motor spindle; Step 2, re-measuring the pre-balancing accuracy of the motor spindle; Step 3, fine balancing of both ends of the grinding wheel cutter holder; Step 4, re-measuring the fine balancing accuracy of both ends of the grinding wheel cutter holder; Step 5, overall verification and final balancing. This invention solves the problems of mutual interference, low accuracy, and poor efficiency that exist in the prior art when dynamically balancing both ends of the spindle separately.

Description

Technical Field

[0001] This invention belongs to the field of rotating machinery fault diagnosis technology, and relates to an integral on-site dynamic balancing method for multi-support grinding wheel spindles. Background Technology

[0002] In precision machine tools, the spindle is a core component, and its dynamic performance directly determines the quality of the machined workpiece. Such spindles are typically supported by multi-stage bearings (such as three-stage bearings), with drive motors and grinding wheels mounted at both ends. The grinding wheel, as the main moving part, directly affects the final quality of the workpiece depending on its smooth operation; therefore, the vibration of the grinding wheel must be controlled during grinding.

[0003] Due to manufacturing errors, material inhomogeneity, and assembly factors, unavoidable imbalances exist in the motor spindle system. Current technologies for dynamic balancing of the spindle at both ends commonly employ traditional single-plane balancing and separate balancing methods for the dynamic balancing of precision machine tool grinding wheel motor spindle systems. The single-plane independent calibration and step-by-step balancing mode—balancing one end first, then the other—fails to consider the spindle cantilever span structure. This fails to address the coupling problem of couple imbalance and force imbalance caused by the spindle cantilever span structure. The balancing process at both ends suffers from severe cross-interference and mutual influence, easily leading to situations where the other end vibrates beyond tolerance after one end has achieved the required balance. This not only results in a repetitive and lengthy balancing process with low efficiency but also frequently exhibits the undesirable phenomenon of increasing vibration amplitude with each calibration.

[0004] In the actual working conditions of precision grinding wheel holders with multi-bearing supports and asymmetrical loads at both ends, the grinding wheel holder, as the direct grinding part, is far more sensitive to vibration than the motor end. Traditional methods fail to distinguish between balancing priorities and correction planes, and do not consider the working characteristics of the grinding wheel holder when differentiating between balancing priorities and correction planes. They neglect the core characteristic that the grinding wheel's vibration sensitivity at the grinding end is far greater than that at the motor end, making it impossible to achieve optimal vibration control at the grinding end. This makes it difficult to completely eliminate vibration interference caused by residual imbalance in the spindle system, ultimately leading to insufficient overall spindle balancing accuracy. This directly reduces the workpiece grinding accuracy and surface finish, and the final balancing accuracy fails to meet the requirements of high-precision machining, resulting in problems such as mutual interference, low precision, and poor efficiency. Therefore, how to achieve a high-speed, high-precision, and non-interfering balancing process under actual working conditions is a pressing problem that needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide an integral on-site dynamic balancing method for multi-supported grinding wheel spindles, which solves the problems of mutual interference, low accuracy, and poor efficiency that exist when the two ends of the spindle are dynamically balanced separately in the prior art.

[0006] The technical solution adopted in this invention is an integral on-site dynamic balancing method for multi-support grinding wheel spindles, which is implemented according to the following steps: Step 1: Pre-balance the motor spindle; Step 2: Recheck the pre-balancing accuracy of the motor spindle; Step 3: Fine balance both ends of the grinding wheel shank; Step 4: Recheck the precision balance of both ends of the grinding wheel cutter holder; Step 5: Overall review and final balancing.

[0007] The invention is further characterized in that, Step 1 specifically involves: Step 1.1: Measure the initial vibration of the motor spindle; Step 1.2: Add a test weight to the calibration plane A, and the unbalance of the calibration plane B is 0. Drive the motor to the working speed to obtain the unbalanced vibration signals of measuring point A and measuring point B. Step 1.3: Add a test weight to the calibration plane B, the unbalance of the calibration plane A is 0, drive the motor to the working speed, and obtain the unbalanced vibration signals of measuring point A and measuring point B; Step 1.4, calculate the influence coefficient; Step 1.5: Solve the complex equation; Step 1.6: Apply the corresponding unbalance amount to the correction plane A and the correction plane B.

[0008] Step 3 specifically involves: Step 3.1: Measure the initial vibration of the grinding wheel cutter bar; Step 3.2: Add a test weight to the calibration plane A, and make the unbalance of the calibration plane C zero. Drive the motor to the working speed to obtain the unbalanced vibration signals of measuring point A and measuring point C. Step 3.3: Add a test weight to the calibration plane C, the unbalance of the calibration plane A is 0, drive the motor to the working speed, and obtain the unbalanced vibration signals of measuring point A and measuring point C; Step 3.4, calculate the influence coefficient; Step 3.5: Solve the complex equation; Step 3.6: Apply the corresponding unbalance amount to the correction plane A.

[0009] Step 1 specifically involves: Step 1.1: Measure the initial vibration of the motor spindle; Disconnect the grinding wheel cutter holder from bearing a, so that the motor spindle forms a rigid rotor structure supported only by bearings a and b at both ends, drive the motor, achieve a balanced speed, and perform dynamic balancing on the entire motor spindle. Measuring points A and B are set at both ends of the motor spindle 8. The two correction planes at both ends of the motor spindle are correction plane A and correction plane B, respectively. Measuring point A and correction plane A are located on the side closer to bearing a, and measuring point B and correction plane B are located on the side closer to bearing b. When the initial correction values ​​of correction planes A and B are zero, drive the motor to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A and B as follows: A 10 B 10 ; A 10 = A 10 ∠α 10 (1) B 10= B 10 ∠β 10 (2) Among them, A 10 Let α be the vibration amplitude at measuring point A. 10 Let B be the phase of measurement point A. 10 Let β be the vibration amplitude at measuring point B. 10 The phase of measurement point B; Step 1.2: Add a test weight to the calibration plane A, applying an unbalance of G. 1L With the imbalance at plane B zero, the motor is driven to its operating speed. Vibrations at measuring points A and B are measured using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and B are respectively A... 1L B 1L ; A 1L =A 1L ∠α 1L (3) B 1L =B 1L ∠β 1L (4) Among them, A 1L To correct the vibration amplitude of measuring point A after adding a test weight to plane A, α 1L To correct the phase of measuring point A after adding a test weight to plane A, B 1L To correct the vibration amplitude of measuring point B after adding a test weight to plane A, β 1L To correct the phase of measuring point B after adding a test weight to plane A; Step 1.3: Add a test weight to the calibration plane B, applying an unbalance of G. 1R With the imbalance at calibration plane A set to 0, the motor is driven to its operating speed. The vibration at measuring points A and B is then measured again using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and B are respectively A... 1R B 1R ; A 1R=A 1R ∠α 1R (5) B 1R =B 1R ∠β 1R (6) Among them, A 1R To determine the vibration amplitude at measuring point A after adding a test weight to the calibration plane B, α 1R To correct the phase of measuring point A after adding a test weight to plane B, B 1R To correct the vibration amplitude of measuring point B after adding a test weight to plane B, β 1R To correct the phase of measuring point B after adding a test weight to plane B; Step 1.4: Using the unbalanced vibration signals measured in steps 1.1 to 1.3, calculate the influence coefficients of correction plane A and correction plane B relative to measuring point A and measuring point B, respectively. (7) (8) (9) (10) Wherein, K1 and K2 are the influence coefficients of the calibration plane A relative to measuring point A and measuring point B, respectively; K3 and K4 are the influence coefficients of the calibration plane B relative to measuring point A and measuring point B, respectively. Step 1.5, input the initial unbalanced vibration signal A from measuring point A and measuring point B. 10 B 10 As the original unbalanced vibration, the unbalanced quantities applied for correction on correction plane A and correction plane B are G, respectively. 1L and G 1R To balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A. 1L Satisfy the equation; K1G 1L +K3G 2R +A 10 =0 (11) An imbalance of G is applied to the correction plane B. 1R Satisfy the equation; K2G 1L +K4G 2R +B 10 =0 (12) According to Cramer's rule, the calculation yields: (13) (14) Among them, G 1L G 1RThese represent the unbalance amounts on correction plane A and correction plane B, respectively. Step 1.6: Based on the calculation results of Step 1.5, apply the corresponding unbalance amount to the correction plane A and the correction plane B to achieve the initial compensation and realize the double-plane dynamic balance at both ends of the motor spindle.

[0010] Step 2 specifically involves measuring the vibration amplitude at both ends of the motor spindle using a handheld measuring instrument after the initial compensation is completed. If the amplitude does not exceed the allowable balance error, proceed to the next step. If the amplitude exceeds the allowable balance error, repeat the pre-balancing of the motor spindle in Step 1.

[0011] Step 3 specifically involves reconnecting the pre-balanced motor spindle and the grinding wheel cutter bar coaxially, restoring the three-position support structure, setting a measuring point C at the end of the grinding wheel cutter bar axially away from the motor spindle, and using the end of the grinding wheel cutter bar away from the motor spindle as the correction plane C. Drive the motor spindle to the balanced speed, measure the vibration values ​​of bearings a and c at both ends of the grinding wheel cutter bar, take the correction plane A and correction plane C for measurement, calculate the unbalance according to step 1.6, and compensate the grinding wheel cutter bar by adding or removing weight. Compensation is performed on bearing c on the grinding wheel cutter bar, while the middle set of bearings a is not compensated as much as possible.

[0012] Step 3 specifically involves: Step 3.1: Measure the initial vibration of the grinding wheel cutter bar; When the initial correction values ​​of correction planes A and C are zero, drive the motor to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A and C, respectively. 20 C 20 ; A 20 = A 20 ∠α 20 (15) C 20= C 20 ∠γ 20 (16) Among them, A 20 Let α be the vibration amplitude at measuring point A. 20 Let C be the phase of measurement point A. 20 Let γ be the vibration amplitude at measuring point C. 20 The phase of measurement point C; Step 3.2: Add a test weight to the calibration plane A to apply an unbalanced amount G. 2L The imbalance at the correction plane C is 0. The drive motor is driven to its operating speed, and the vibration at measuring points A and C is measured using a handheld balancing instrument. The imbalance vibration signals at measuring points A and C are respectively A 2L C 2L : A 2L =A 2L∠α 2L (17) C 2L =C 2L ∠γ 2L (18) Among them, A 2L To determine the vibration amplitude at point A after adding a test weight to the calibration plane A, α 2L To correct the phase of measuring point A after adding a test weight to plane A, C 2L To correct the vibration amplitude at measuring point C after adding a test weight to plane A, γ 2L To correct the phase of the measuring point C after adding a test weight to plane A; Step 3.3: Add a test weight to the calibration plane C and apply an unbalanced amount G. 2R With the imbalance at calibration plane A set to 0, the motor is driven to its operating speed. Vibrations at measuring points A and C are measured using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and C are respectively A... 2R C 2R : A 2R =A 2R ∠α 2R (19) C 2R =C 2R ∠γ 2R (20) Among them, A 2R To determine the vibration amplitude at point A after adding a test weight to the calibration plane C, α 2R To correct the phase of measuring point A after adding a test weight to plane C, C 2R To correct the vibration amplitude of measuring point C after adding a test weight to plane C, γ 2R To correct the phase of the measuring point C after adding a test weight to plane C; Step 3.4, calculate the influence coefficient; (twenty one) (twenty two) (twenty three) (twenty four) Wherein, K5 and K6 are the influence coefficients of the calibration plane A relative to measuring point A and measuring point C, respectively; K7 and K8 are the influence coefficients of the calibration plane C relative to measuring point A and measuring point C, respectively. Step 3.5, input the initial unbalanced vibration signal A from measuring points A and C. 20 C 20 As the original unbalanced vibration, the unbalanced quantities applied for correction on correction plane A and correction plane C are G, respectively. 2L and G 2RTo balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A. 1L Satisfy the equation; K5G 2L +K7G 2R +A 20 =0 (25) An imbalance of G is applied to the correction plane C. 2R Satisfy the equation; K6G 2L +K7G 2R +C 20 =0 (26) According to Cramer's rule, the imbalance is calculated as follows: (27) (28) Among them, G 2L G 2R These represent the unbalance amounts in correction plane A and correction plane C, respectively. Step 3.6: Based on the calculation results of step 3.5, apply the corresponding unbalance amount on the correction plane A and correction plane C to achieve double-sided dynamic balance of the grinding wheel spindle end.

[0013] Step 4 involves measuring the vibration amplitude at both ends of the grinding wheel cutter bar using a handheld measuring instrument. If the amplitude does not exceed the allowable balance error, proceed to the next step. If the amplitude exceeds the allowable balance error, repeat the fine balancing of both ends of the grinding wheel cutter bar in step 3.

[0014] Step 5: Measure the vibration amplitude of bearings b and c. The grinding wheel shank is the machining area, and the vibration amplitude directly determines the grinding accuracy. During dynamic balancing, minimize the vibration amplitude of bearings a and c at both ends of the grinding wheel shank. The vibration amplitude of bearing b on the motor spindle should be within acceptable limits. If the vibration amplitude of bearing b exceeds the tolerance, compensate for the weight of bearing b. Finally, ensure that the vibration amplitude of all bearing positions in the three-stage bearing structure is within acceptable limits.

[0015] Step 5: Using the two correction planes at both ends of the motor spindle, namely correction plane A and correction plane B, simultaneously collect the vibration amplitude and phase of the two planes and perform dual-plane balancing; similarly, using the end of the grinding wheel cutter bar away from the motor spindle as correction plane C, the unbalanced amount after calculation is compensated first on correction plane C; bearing a is located in the middle position of the three-stage bearing structure, and no unbalanced amount compensation is performed, or the compensation amount does not exceed 10% of the total compensation amount.

[0016] The beneficial effects of this invention are that the integrated on-site dynamic balancing method for multi-support grinding wheel spindles eliminates the need for repeated separate calibration at both ends of the spindle. It allows for integrated on-site dynamic balancing operations directly on the machine without disassembling the spindle. It can accurately identify the unbalanced coupling relationship under multi-support, multi-point support structures, eliminate cross-interference between calibration surfaces at both ends, significantly improve the final dynamic balancing accuracy, effectively reduce the overall machine vibration amplitude under high-speed spindle operation, shorten the on-site dynamic balancing debugging and repeated calibration time, and significantly reduce subsequent equipment maintenance workload and long-term repair costs. Furthermore, it allows for flexible matching of different dynamic balancing calibration strategies as needed, prioritizing the vibration index of the grinding wheel end, perfectly adapting to the high-precision and high-stability machining requirements of precision grinding. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the multi-support mold spindle structure of the present invention; Figure 2 This is a flowchart of the integral on-site dynamic balancing method for multi-support grinding wheel spindles according to the present invention; In the diagram, 1. Calibration plane A, 2. Measuring point A, 3. Bearing a, 4. Measuring point B, 5. Calibration plane B, 6. Bearing b, 7. Motor, 8. Motor spindle, 9. Grinding wheel, 10. Grinding wheel tool holder, 11. Bearing c, 12. Calibration plane C, 13. Measuring point C. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0019] Example 1 The present invention provides a multi-support mold spindle structure, such as... Figure 1 As shown, the device includes a motor 7, with a motor spindle 8 inside. Bearings a3 and b6 are respectively sleeved at both ends of the motor spindle 8, and the motor spindle 8 is supported by bearings a3 and b6. The end of the motor spindle 8 closest to bearing a3 is connected to a grinding wheel holder 10, on which a grinding wheel 9 is mounted. The end of the grinding wheel holder 10 furthest from bearing a3 is sleeved with bearing c11. Bearing a3 consists of two sets of bearings installed in series; bearing b6 consists of one set of bearings installed back to back. Bearings a3 and b6 are both angular contact ball bearings, and bearing c11 consists of two angular contact ball bearings, forming a three-stage bearing structure.

[0020] Example 2 This invention provides an integral on-site dynamic balancing method for multi-support grinding wheel spindles, which is implemented according to the following steps: Step 1: Pre-balance the motor spindle 8; Step 2: Recheck the pre-balancing accuracy of the motor spindle 8; Step 3: Fine balance both ends of the grinding wheel cutter holder 10; Step 4: Recheck the precision balance accuracy at both ends of the grinding wheel cutter holder 10; Step 5: Overall review and final balancing.

[0021] Example 3 This invention provides an integral on-site dynamic balancing method for multi-support grinding wheel spindles, which is implemented according to the following steps: Step 1: Pre-balance the motor spindle 8; Step 1 specifically involves: Step 1: Pre-balance the motor spindle 8; Step 1.1: Measure the initial vibration of the motor spindle 8; Step 1.2: Add a test weight to the calibration plane A1, the unbalance of the calibration plane B5 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.3: Add a test weight to the calibration plane B5, the unbalance of the calibration plane A1 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.4, calculate the influence coefficient; Step 1.5: Solve the complex equation; Step 1.6: Apply the corresponding unbalance amount to the correction plane A1 and the correction plane B5.

[0022] Step 2: Recheck the pre-balancing accuracy of the motor spindle 8; Step 3: Fine balance both ends of the grinding wheel cutter holder 10; Step 4: Recheck the precision balance accuracy at both ends of the grinding wheel cutter holder 10; Step 5: Overall review and final balancing.

[0023] Example 4 This invention provides an integral on-site dynamic balancing method for multi-support grinding wheel spindles, which is implemented according to the following steps: Step 1: Pre-balance the motor spindle 8; Step 1 specifically involves: Step 1: Pre-balance the motor spindle 8; Step 1.1: Measure the initial vibration of the motor spindle 8; Disconnect the grinding wheel holder 10 from the bearing a3, so that the motor spindle 8 forms a rigid rotor structure supported only by the bearings a3 and b6 at both ends, drive the motor 7 to achieve a balanced speed, and perform dynamic balancing on the motor spindle 8 as a whole. Measuring points A2 and B4 are set at both ends of the motor spindle 8. The two calibration planes at both ends of the motor spindle 8 are calibration plane A1 and calibration plane B5, respectively. Measuring point A2 and calibration plane A1 are located on the side closer to bearing a3, and measuring point B4 and calibration plane B5 are located on the side closer to bearing b6.

[0024] When the initial correction values ​​of correction planes A1 and B5 are zero, drive motor 7 to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A2 and B4.

[0025] Step 1.2: Add a test weight to the calibration plane A1, the unbalance of the calibration plane B5 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.3: Add a test weight to the calibration plane B5, the unbalance of the calibration plane A1 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.4, calculate the influence coefficient; Step 1.5: Solve the complex equation; Step 1.6: Apply the corresponding unbalance amount to the correction plane A1 and the correction plane B5.

[0026] Step 2: Recheck the pre-balancing accuracy of the motor spindle 8; Step 3: Fine balance both ends of the grinding wheel cutter holder 10; Step 4: Recheck the precision balance accuracy at both ends of the grinding wheel cutter holder 10; Step 5: Overall review and final balancing.

[0027] Example 5 This invention provides an integral on-site dynamic balancing method for multi-support grinding wheel spindles, the flowchart of which is shown below. Figure 2 As shown, please follow these steps: Step 1: Pre-balance the motor spindle 8; Step 1.1: Measure the initial vibration of the motor spindle 8; Disconnect the grinding wheel cutter bar 10 from the bearing a3, so that the motor spindle 8 forms a rigid rotor structure supported only by the bearings a3 and b6 at both ends, drive the motor 7 to reach the balanced speed, and perform dynamic balancing on the entire motor spindle 8; Measuring points A2 and B4 are set at both ends of the motor spindle 8. The two calibration planes at both ends of the motor spindle 8 are calibration plane A1 and calibration plane B5, respectively. Measuring point A2 and calibration plane A1 are located on the side closer to bearing a3, and measuring point B4 and calibration plane B5 are located on the side closer to bearing b6.

[0028] When the initial correction values ​​of correction planes A1 and B5 are zero, drive motor 7 to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A2 and B4. Step 1.2: Add a test weight to the calibration plane A1, the unbalance of the calibration plane B5 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.3: Add a test weight to the calibration plane B5, the unbalance of the calibration plane A1 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point B4. Step 1.4, calculate the influence coefficient; Step 1.5: Solve the complex equation; Step 1.6: Apply the corresponding unbalance amount to the correction plane A1 and the correction plane B5.

[0029] Step 2: Recheck the pre-balancing accuracy of the motor spindle 8; Step 3: Fine balance both ends of the grinding wheel cutter holder 10; Step 3.1, measure the initial vibration of the grinding wheel cutter holder 10; Step 3.2: Add a test weight to the calibration plane A1, the unbalance of the calibration plane C12 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point C13; Step 3.3: Add a test weight to the calibration plane C12, the unbalance of the calibration plane A1 is 0, drive motor 7 to the working speed, and obtain the unbalanced vibration signals of measuring point A2 and measuring point C13; Step 3.4, calculate the influence coefficient; Step 3.5: Solve the complex equation; Step 3.6: Apply the corresponding unbalance amount to the correction plane A1 and the correction plane C12.

[0030] Step 4: Recheck the precision balance accuracy at both ends of the grinding wheel cutter holder 10; Step 5: Overall review and final balancing.

[0031] Example 6 This invention provides an integral on-site dynamic balancing method for multi-support grinding wheel spindles, which is implemented according to the following steps: Step 1: Pre-balance the motor spindle 8; Step 1.1: Measure the initial vibration of the motor spindle 8; Disconnect the grinding wheel holder 10 from the bearing a3, so that the motor spindle 8 forms a rigid rotor structure supported only by the bearings a3 and b6 at both ends, drive the motor 7 to achieve a balanced speed, and perform dynamic balancing on the motor spindle 8 as a whole. Measuring points A2 and B4 are set at both ends of the motor spindle 8. The two calibration planes at both ends of the motor spindle 8 are calibration plane A1 and calibration plane B5, respectively. Measuring point A2 and calibration plane A1 are located on the side closer to bearing a3, and measuring point B4 and calibration plane B5 are located on the side closer to bearing b6.

[0032] When the initial correction values ​​of correction planes A1 and B5 are zero, drive motor 7 to its operating speed, and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A2 and B4, respectively. 10 B 10 ; A 10 = A 10 ∠α 10 (1) B 10= B 10 ∠β 10 (2) Among them, A 10 Let α be the vibration amplitude at measuring point A2. 10 Let B be the phase of measurement point A2. 10 Let β be the vibration amplitude at measuring point B4. 10 The phase of measurement point B4.

[0033] Step 1.2: Add a test weight to the calibration plane A1, applying an unbalance of G. 1L With the imbalance at calibration plane B5 set to 0, drive motor 7 to its operating speed. Vibrations at measuring points A2 and B4 are measured using a handheld balancing instrument. The imbalance vibration signals at measuring points A2 and B4 are respectively A... 1L B 1L ; A 1L =A 1L ∠α 1L (3) B 1L =B 1L ∠β 1L (4) Among them, A 1L To correct the vibration amplitude of measuring point A2 after adding a test weight to plane A1, α 1L To correct the phase of measuring point A2 after adding a test weight to plane A1, B 1L To correct the vibration amplitude of measuring point B4 after adding a test weight to plane A1, β 1L To correct the phase of the measuring point B4 after adding a test weight to plane A1.

[0034] Step 1.3: Add a test weight to the calibration plane B5, applying an unbalance of G. 1R The imbalance of the calibration plane A1 is 0. The drive motor is driven to its operating speed (7). The vibration of measuring points A2 and B4 is measured again using a handheld balancing instrument. The imbalance vibration signals of measuring points A2 and B4 are respectively A 1R B 1R ; A 1R =A 1R ∠α 1R (5) B 1R =B 1R ∠β 1R (6) Among them, A 1R To determine the vibration amplitude at measuring point A2 after adding a test weight to the calibration plane B5, α 1R To correct the phase of measuring point A2 after adding a test weight to plane B5, B 1R To correct the vibration amplitude of measuring point B4 after adding a test weight to plane B5, β 1R To correct the phase of the measuring point B4 after adding a test weight to plane B5.

[0035] Step 1.4: Using the unbalanced vibration signals measured in steps 1.1 to 1.3, calculate the influence coefficients of correction plane A1 and correction plane B5 relative to measuring point A2 and measuring point B4, respectively. (7) (8) (9) (10) Wherein, K1 and K2 are the influence coefficients of the calibration plane A1 relative to measuring points A2 and B4, respectively. K3 and K4 are the influence coefficients of the calibration plane B5 relative to measuring points A2 and B4, respectively.

[0036] Step 1.5, input the initial unbalanced vibration signal A from measuring points A2 and B4. 10 B 10 As the original unbalanced vibration, the unbalanced quantities applied to the correction planes A1 and B5 are G, respectively. 1L and G 1R To balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A1. 1L Satisfy the equation; K1G 1L +K3G 2R +A 10 =0 (11) An imbalance of G is applied to the correction plane B5. 1R Satisfy the equation; K2G 1L +K4G 2R +B 10 =0 (12) According to Cramer's rule, the calculation yields: (13) (14) Among them, G 1L G 1RThese represent the unbalance amounts of correction plane A1 and correction plane B5, respectively.

[0037] Step 1.6: Based on the calculation results of Step 1.5, apply the corresponding unbalance amount to the correction plane A1 and the correction plane B5 to achieve the initial compensation and realize the double-plane dynamic balance at both ends of the motor spindle 8.

[0038] Step 2, recalculation accuracy; After the initial compensation is completed, use a handheld measuring instrument to measure the vibration amplitude at both ends of the motor spindle 8. If it does not exceed the allowable balance error, proceed to the next step. If it exceeds the allowable balance error, repeat the pre-balancing of the motor spindle 8 in step 1.

[0039] Step 3: Fine balance both ends of the grinding wheel cutter holder 10; Reconnect the pre-balanced motor spindle 8 and grinding wheel cutter holder 10 coaxially, restoring the three-position support structure. Set a measuring point C13 at the end of the grinding wheel cutter holder 10 axially away from the motor spindle 8, and set the correction plane C12 at the end of the grinding wheel cutter holder 10 away from the motor spindle 8. Drive the motor spindle 8 to the balance speed and measure the vibration values ​​of the bearings a3 and c11 at both ends of the grinding wheel cutter holder 10. Take the correction planes A1 and C12 for measurement. Calculate the imbalance according to step 1.6, and compensate the grinding wheel cutter holder 10 by adding or removing weight. Compensate the bearings c11 on the grinding wheel cutter holder 10, and try not to compensate the middle set of bearings a3.

[0040] Step 3.1, measure the initial vibration of the grinding wheel cutter holder 10; When the initial correction values ​​of correction planes A1 and C12 are zero, drive motor 7 to its operating speed, and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A2 and C13, respectively. 20 C 20 ; A 20 = A 20 ∠α 20 (15) C 20= C 20 ∠γ 20 (16) Among them, A 20 Let α be the vibration amplitude at measuring point A2. 20 For the phase of measurement point A2, C 20 Let γ be the vibration amplitude at measuring point C13. 20 The phase of measurement point C13.

[0041] Step 3.2: Add a test weight to the calibration plane A1 to apply an unbalanced amount G. 2LThe imbalance of the calibration plane C12 is 0. The drive motor 7 is driven to the operating speed. The vibration of measuring points A2 and C13 is measured using a handheld balancing instrument. The imbalance vibration signals of measuring points A2 and C13 are respectively A 2L C 2L : A 2L =A 2L ∠α 2L (17) C 2L =C 2L ∠γ 2L (18) Among them, A 2L To determine the vibration amplitude at measuring point A2 after adding a test weight to the calibration plane A1, α 2L To correct the phase of measuring point A2 after adding a test weight to plane A1, C 2L To correct the vibration amplitude at measuring point C13 after adding a test weight to plane A1, γ 2L To correct the phase of the measuring point C13 after adding a test weight to plane A1.

[0042] Step 3.3: Add a test weight to the calibration plane C12 and apply an unbalanced amount G. 2R With the imbalance of the calibration plane A1 being 0, the drive motor 7 was set to its operating speed. Vibrations at measuring points A2 and C13 were measured using a handheld balancing instrument. The imbalance vibration signals at measuring points A2 and C13 were A... 2R C 2R : A 2R =A 2R ∠α 2R (19) C 2R =C 2R ∠γ 2R (20) Among them, A 2R To determine the vibration amplitude at measuring point A2 after adding a test weight to the calibration plane C12, α 2R To correct the phase of measuring point A2 after adding a test weight to plane C12, C 2R To correct the vibration amplitude of measuring point C13 after adding a test weight to plane C12, γ 2R To correct the phase of the measuring point C13 after adding a test weight to the plane C12.

[0043] Step 3.4, calculate the influence coefficient; (twenty one) (twenty two) (twenty three) (twenty four) Wherein, K5 and K6 are the influence coefficients of the calibration plane A1 relative to measuring points A2 and C13, respectively; K7 and K8 are the influence coefficients of the calibration plane C12 relative to measuring points A2 and C13, respectively.

[0044] Step 3.5, input the initial unbalanced vibration signal A from measuring points A2 and C13. 20 C 20 As the original unbalanced vibration, the unbalanced quantities applied for correction on correction plane A1 and correction plane C12 are G, respectively. 2L and G 2R To balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A1. 1L Satisfy the equation; K5G 2L +K7G 2R +A 20 =0 (25) An imbalance of G is applied to the correction plane C12. 2R Satisfy the equation; K6G 2L +K7G 2R +C 20 =0 (26) According to Cramer's rule, the imbalance is calculated as follows: (27) (28) Among them, G 2L G 2R These represent the unbalance amounts of correction plane A1 and correction plane C12, respectively.

[0045] Step 3.6: Based on the calculation results of step 3.5, apply the corresponding unbalance amount to the correction plane A1 and correction plane C12 to achieve double-sided dynamic balance of the grinding wheel spindle end.

[0046] Step 4, recalculation accuracy; Use a handheld measuring instrument to measure the vibration amplitude at both ends of the grinding wheel cutter bar 10. If it does not exceed the allowable balance error, proceed to the next step. If it exceeds the allowable balance error, repeat the fine balancing of both ends of the grinding wheel cutter bar 10 in step 3.

[0047] Step 5: Overall review and final balancing.

[0048] Measure the vibration amplitude of bearings b6 and c11. The grinding wheel shank 10 is the machining area, and the vibration amplitude directly determines the grinding accuracy. During dynamic balancing, minimize the vibration amplitude of bearings a3 and c11 at both ends of the grinding wheel shank 10. The vibration amplitude of bearing b6 on the motor spindle 8 is acceptable. If the vibration amplitude of bearing b6 exceeds the tolerance, compensate for the weight of bearing b6. Finally, ensure that the vibration amplitude of all bearing positions in the three-stage bearing structure is acceptable.

[0049] Using the two correction planes at both ends of the motor spindle 8, namely correction plane A1 and correction plane B5, the vibration amplitude and phase of the two planes are collected simultaneously to perform dual-plane balancing; similarly, using the end of the grinding wheel cutter bar 10 away from the motor spindle 8 as the correction plane C12, the calculated unbalance is compensated first on the correction plane C12; bearing a3 is located in the middle position of the three-stage bearing structure, and no unbalance compensation is performed, or the compensation amount does not exceed 10% of the total compensation amount.

[0050] This invention provides an integrated on-site dynamic balancing method for multi-support grinding wheel spindles. Through trial weight experiments, the influence coefficient matrix of the system is identified, allowing for the simultaneous calculation of the optimal weight distribution on both correction planes. This achieves rapid and accurate overall dynamic balancing, eliminating the mutual influence between the two ends of the balance. Simultaneously, it prioritizes the dynamic balancing accuracy of the grinding wheel machining end, adapting to machine tool machining precision. The double-plane balancing method simultaneously solves for the unbalance on both correction planes, optimizing the balancing weight calculation. The balancing results are accurate, with minimal residual vibration and high balancing precision. It simplifies the on-site dynamic balancing test procedures and reduces the operation time. By eliminating force and couple imbalances in one step, it is more suitable for long-span, multi-support spindle structures, making the balancing results more feasible. It is suitable for various rotor systems with multi-support and elastic shaft characteristics, and is not limited by specific spindle structures or speeds, exhibiting strong versatility.

[0051] This invention provides an integrated on-site dynamic balancing method for multi-support grinding wheel spindles. Through a step-by-step approach of "disengaging pre-balancing and connecting final balancing," the motor end is first independently balanced under two-point support. In the final balancing stage, the right end of the motor is no longer used as a correction plane; only minor compensation is performed when deviations occur. Both the pre-balancing and final balancing stages utilize a double-plane balancing method, minimizing vibration at the grinding wheel spindle end and achieving optimal vibration control at the machining end. This directly improves grinding accuracy while ensuring acceptable vibration at the motor end bearings, balancing spindle operational stability and machining accuracy. This method avoids the disruption of the pre-balancing at the motor end caused by the final balancing, significantly reducing the number of balancing iterations. System identification can be completed with only two trial runs, resulting in high efficiency. Limiting the compensation amount at intermediate support positions, with only minor or no compensation, avoids damage to the spindle structure and bearing fit accuracy caused by drilling or milling at intermediate positions. It also reduces secondary correction at the motor end, lowering the risk of spindle structural damage, effectively extending spindle lifespan and operational stability, and meeting the high-precision, high-efficiency dynamic balancing requirements of high-end precision machine tools.

Claims

1. A method for integral on-site dynamic balancing of multi-support grinding wheel spindles, characterized in that, The specific steps are as follows: Step 1: Pre-balance the motor spindle; Step 2: Recheck the pre-balancing accuracy of the motor spindle; Step 3: Fine balance both ends of the grinding wheel shank; Step 4: Recheck the precision balance of both ends of the grinding wheel cutter holder; Step 5: Overall review and final balancing.

2. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 1, characterized in that, Step 1 specifically involves: Step 1.1: Measure the initial vibration of the motor spindle; Step 1.2: Add a test weight to the calibration plane A, and the unbalance of the calibration plane B is 0. Drive the motor to the working speed to obtain the unbalanced vibration signals of measuring point A and measuring point B. Step 1.3: Add a test weight to the calibration plane B, the unbalance of the calibration plane A is 0, drive the motor to the working speed, and obtain the unbalanced vibration signals of measuring point A and measuring point B; Step 1.4, calculate the influence coefficient; Step 1.5: Solve the complex equation; Step 1.6: Apply the corresponding unbalance amount to the correction plane A and the correction plane B.

3. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 2, characterized in that, Step 3 specifically involves: Step 3.1: Measure the initial vibration of the grinding wheel cutter bar; Step 3.2: Add a test weight to the calibration plane A, and make the unbalance of the calibration plane C zero. Drive the motor to the working speed to obtain the unbalanced vibration signals of measuring point A and measuring point C. Step 3.3: Add a test weight to the calibration plane C, the unbalance of the calibration plane A is 0, drive the motor to the working speed, and obtain the unbalanced vibration signals of measuring point A and measuring point C; Step 3.4, calculate the influence coefficient; Step 3.5: Solve the complex equation; Step 3.6: Apply the corresponding unbalance amount to the correction plane A.

4. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 3, characterized in that, Step 1 specifically involves: Step 1.1: Measure the initial vibration of the motor spindle; Disconnect the grinding wheel cutter holder from bearing a, so that the motor spindle forms a rigid rotor structure supported only by bearings a and b at both ends, drive the motor, achieve a balanced speed, and perform dynamic balancing on the entire motor spindle. Measuring points A and B are set at both ends of the motor spindle 8. The two correction planes at both ends of the motor spindle are correction plane A and correction plane B, respectively. Measuring point A and correction plane A are located on the side closer to bearing a, and measuring point B and correction plane B are located on the side closer to bearing b. When the initial correction values ​​of correction planes A and B are zero, drive the motor to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A and B as follows: A 10 B 10 ; A 10 = A 10 ∠α 10 (1) B 10= B 10 ∠β 10 (2) Among them, A 10 Let α be the vibration amplitude at measuring point A, and ∠α be the vibration amplitude at measuring point A. 10 Let B be the phase of measurement point A. 10 Let β be the vibration amplitude at measuring point B. 10 The phase of measurement point B; Step 1.2: Add a test weight to the calibration plane A, applying an unbalance of G. 1L With the imbalance at plane B zero, the motor is driven to its operating speed. Vibrations at measuring points A and B are measured using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and B are respectively A... 1L B 1L ; A 1L =A 1L ∠α 1L (3) B 1L =B 1L ∠β 1L (4) Among them, A 1L To correct the vibration amplitude of measuring point A after adding a test weight to plane A, α 1L To correct the phase of measuring point A after adding a test weight to plane A, B 1L To correct the vibration amplitude of measuring point B after adding a test weight to plane A, β 1L To correct the phase of measuring point B after adding a test weight to plane A; Step 1.3: Add a test weight to the calibration plane B, applying an unbalance of G. 1R With the imbalance at calibration plane A set to 0, the motor is driven to its operating speed. The vibration at measuring points A and B is then measured again using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and B are respectively A... 1R B 1R ; A 1R =A 1R ∠α 1R (5) B 1R =B 1R ∠β 1R (6) Among them, A 1R To determine the vibration amplitude at measuring point A after adding a test weight to the calibration plane B, α 1R To correct the phase of measuring point A after adding a test weight to plane B, B 1R To correct the vibration amplitude of measuring point B after adding a test weight to plane B, β 1R To correct the phase of measuring point B after adding a test weight to plane B; Step 1.4: Using the unbalanced vibration signals measured in steps 1.1 to 1.3, calculate the influence coefficients of correction plane A and correction plane B relative to measuring point A and measuring point B, respectively. （7） （8） （9） （10） Wherein, K1 and K2 are the influence coefficients of the calibration plane A relative to measuring point A and measuring point B, respectively; K3 and K4 are the influence coefficients of the calibration plane B relative to measuring point A and measuring point B, respectively. Step 1.5, input the initial unbalanced vibration signal A from measuring point A and measuring point B. 10 B 10 As the original unbalanced vibration, the unbalanced quantities applied for correction on correction plane A and correction plane B are G, respectively. 1L and G 1R To balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A. 1L Satisfy the equation; K1G 1L + K3G 2R +A 10 =0(11) An imbalance of G is applied to the correction plane B. 1R Satisfy the equation; K2G 1L + K4G 2R +B 10 =0(12) According to Cramer's rule, the calculation yields: （13） （14） Among them, G 1L G 1R These represent the unbalance amounts on correction plane A and correction plane B, respectively. Step 1.6: Based on the calculation results of Step 1.5, apply the corresponding unbalance amount to the correction plane A and the correction plane B to achieve the initial compensation and realize the double-plane dynamic balance at both ends of the motor spindle.

5. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 4, characterized in that, Step 2 specifically involves measuring the vibration amplitude at both ends of the motor spindle using a handheld measuring instrument after the initial compensation is completed. If the amplitude does not exceed the allowable balance error, proceed to the next step. If the amplitude exceeds the allowable balance error, repeat the pre-balancing of the motor spindle in Step 1.

6. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 5, characterized in that, Step 3 specifically involves reconnecting the pre-balanced motor spindle and the grinding wheel cutter bar coaxially, restoring the three-position support structure, setting a measuring point C at the end of the grinding wheel cutter bar axially away from the motor spindle, and using the end of the grinding wheel cutter bar away from the motor spindle as the correction plane C. Drive the motor spindle to the balanced speed, measure the vibration values ​​of bearings a and c at both ends of the grinding wheel cutter bar, take the correction plane A and correction plane C for measurement, calculate the unbalance according to step 1.6, and compensate the grinding wheel cutter bar by adding or removing weight. Compensation is performed on bearing c on the grinding wheel cutter bar, while the middle set of bearings a is not compensated as much as possible.

7. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 6, characterized in that, Step 3 specifically involves: Step 3.1: Measure the initial vibration of the grinding wheel cutter bar; When the initial correction values ​​of correction planes A and C are zero, drive the motor to its operating speed and use a handheld measuring instrument to measure and record the initial unbalanced vibration signals at measuring points A and C, respectively. 20 C 20 ; A 20 = A 20 ∠α 20 (15) C 20= C 20 ∠γ 20 (16) Among them, A 20 Let α be the vibration amplitude at measuring point A, and ∠α be the vibration amplitude at measuring point A. 20 Let C be the phase of measurement point A. 20 Let γ be the vibration amplitude at measuring point C. 20 The phase of measurement point C; Step 3.2: Add a test weight to the calibration plane A to apply an unbalanced amount G. 2L The imbalance at the correction plane C is 0. The drive motor is driven to its operating speed, and the vibration at measuring points A and C is measured using a handheld balancing instrument. The imbalance vibration signals at measuring points A and C are respectively A 2L C 2L : A 2L =A 2L ∠α 2L (17) C 2L =C 2L ∠γ 2L (18) Among them, A 2L To determine the vibration amplitude at point A after adding a test weight to the calibration plane A, α 2L To correct the phase of measuring point A after adding a test weight to plane A, C 2L To correct the vibration amplitude at measuring point C after adding a test weight to plane A, γ 2L To correct the phase of the measuring point C after adding a test weight to plane A; Step 3.3: Add a test weight to the calibration plane C and apply an unbalanced amount G. 2R With the imbalance at calibration plane A set to 0, the motor is driven to its operating speed. Vibrations at measuring points A and C are measured using a handheld balancing instrument. The unbalanced vibration signals at measuring points A and C are respectively A... 2R C 2R : A 2R =A 2R ∠α 2R (19) C 2R =C 2R ∠γ 2R (20) Among them, A 2R To determine the vibration amplitude at point A after adding a test weight to the calibration plane C, α 2R To correct the phase of measuring point A after adding a test weight to plane C, C 2R To correct the vibration amplitude of measuring point C after adding a test weight to plane C, γ 2R To correct the phase of the measuring point C after adding a test weight to plane C; Step 3.4, calculate the influence coefficient; （21） （22） （23） （24） Wherein, K5 and K6 are the influence coefficients of the calibration plane A relative to measuring point A and measuring point C, respectively; K7 and K8 are the influence coefficients of the calibration plane C relative to measuring point A and measuring point C, respectively. Step 3.5, input the initial unbalanced vibration signal A from measuring points A and C. 20 C 20 As the original unbalanced vibration, the unbalanced quantities applied for correction on correction plane A and correction plane C are G, respectively. 2L and G 2R To balance the original unbalanced vibration, an unbalance amount G is applied to the correction plane A. 1L Satisfy the equation; K5G 2L +K7G 2R +A 20 =0 (25) An imbalance of G is applied to the correction plane C. 2R Satisfy the equation; K6G 2L +K7G 2R +C 20 =0(26) According to Cramer's rule, the imbalance is calculated as follows: （27） （28） Among them, G 2L G 2R These represent the unbalance amounts in correction plane A and correction plane C, respectively. Step 3.6: Based on the calculation results of step 3.5, apply the corresponding unbalance amount on the correction plane A and correction plane C to achieve double-sided dynamic balance of the grinding wheel spindle end.

8. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 7, characterized in that, Step 4 involves measuring the vibration amplitude at both ends of the grinding wheel cutter bar using a handheld measuring instrument. If the amplitude does not exceed the allowable balance error, proceed to the next step. If the amplitude exceeds the allowable balance error, repeat the fine balancing of both ends of the grinding wheel cutter bar in step 3.

9. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 8, characterized in that, Step 5: Measure the vibration amplitude of bearings b and c. The grinding wheel shank is the machining area, and the vibration amplitude directly determines the grinding accuracy. During dynamic balancing, minimize the vibration amplitude of bearings a and c at both ends of the grinding wheel shank. The vibration amplitude of bearing b on the motor spindle should be within acceptable limits. If the vibration amplitude of bearing b exceeds the tolerance, compensate for the weight of bearing b. Finally, ensure that the vibration amplitude of all bearing positions in the three-stage bearing structure is within acceptable limits.

10. The integral on-site dynamic balancing method for multi-support grinding wheel spindles according to claim 9, characterized in that, Step 5: Using the two correction planes at both ends of the motor spindle, namely correction plane A and correction plane B, simultaneously collect the vibration amplitude and phase of the two planes and perform dual-plane balancing; similarly, using the end of the grinding wheel cutter bar away from the motor spindle as correction plane C, the unbalanced amount after calculation is compensated first on correction plane C; bearing a is located in the middle position of the three-stage bearing structure, and no unbalanced amount compensation is performed, or the compensation amount does not exceed 10% of the total compensation amount.

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