Dynamic balance method based on single station

Abstract

The invention discloses a dynamic balancing method based on a single station, and the method comprises the following steps: installing a measured workpiece on a dynamic balancing machine, installing a laser generator, and connecting the laser generator to a rotating speed sensor, a vibration sensor and a data collection system; the measured workpiece is driven to rotate at a constant speed, and the unbalance amount position information of the measured workpiece is determined; the method comprises the following steps: acquiring the starting time of detected unbalance, and then confirming the continuous working time of laser; the total balance time is calculated by adopting a dynamic compensation function formula # imgabs0 #, a laser generator is controlled, and synchronous laser gasification de-weighting is implemented in the dynamic rotation process of the measured workpiece. Synchronous laser gasification de-weighting is implemented in the dynamic rotation process of the tested workpieces, delay from data detection to instruction execution is reduced, reference conversion errors caused by station conversion are avoided, consistency of dynamic balance test references is guaranteed, assembly line work of the tested workpieces of the same batch is supported, and production efficiency is improved. And the efficiency and the accuracy of dynamic balance detection are greatly improved.

Description

Technical Field

[0001] The invention relates to the field of dynamic balancing methods for rotating bodies, and in particular to a dynamic balancing method based on a single station. Background Art

[0002] Traditional dynamic balancing adopts a dual-station design with separate detection station and balance correction station. The balance detection station is a high-precision station. External force acting on the balance detection workpiece will affect the accuracy of the balance. Because the balance correction station requires external force to complete the balance correction work, multiple stations are required to complete balance detection and correction.

[0003] Although this layout simplifies the system structure to a certain extent, it has many inherent defects, which seriously restrict the accuracy, efficiency and scope of application of dynamic balancing processing. First, when the workpiece is transferred between the two stations, a slight offset of the clamping reference will inevitably occur. This offset will lead to: For example: Phase angle measurement error: It can usually reach ±2 degrees to ±5 degrees. This error will gradually increase in the subsequent balance correction. Secondly, during the transfer process, the workpiece is exposed to the workshop environment and is disturbed by vibration: The vibration of the transfer machine is transmitted to the workpiece, affecting the initial unbalanced state. Finally, the double-station design causes a time delay between detection and processing, which makes the initial measurement data invalid and needs to be recalibrated. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a dynamic balancing method based on a single station, comprising the following steps: Step 1: Install the workpiece to be measured on the main shaft of the dynamic balancing machine to ensure that it is firmly fixed; Install the laser generator, adjust the position of the laser generator to be perpendicular to the surface of the workpiece to be measured, and the distance meets the processing requirements; Connect the laser generator to the speed sensor, the vibration sensor and the data acquisition system; Step 2: Drive the workpiece to be measured to rotate at a uniform speed, start detection after the speed stabilizes, detect the centrifugal force vibration caused by the imbalance through the vibration sensor, and determine the imbalance amount and position information of the workpiece to be measured; Step 3: Obtain the start time of the imbalance detection, and then confirm the continuous working time of the laser; Step 4: Use the dynamic compensation function formula Calculate the total balancing time, where T1 is the total balancing time, T0 is the starting time when the imbalance is detected, n is the rotation speed of the workpiece being measured, and Lc is the position information of the imbalance amount of the workpiece being measured; Step 5: Control the laser generator to implement synchronous laser vaporization and deweighting during the dynamic rotation of the workpiece being measured.

[0005] Furthermore, in step 3, the calculation of the laser continuous working time satisfies the following formula: , where Tc is the continuous working time of the laser, L is the circumferential length of the unbalanced position of the workpiece being measured, in millimeters, and D is the diameter of the workpiece being measured.

[0006] Furthermore, in step 3, the calculation of the start time of detecting the imbalance satisfies the following formula: .

[0007] Furthermore, in step 4, the calculation of the total equilibrium time satisfies the following formula: T1=1.1~1.5×(T0+Lc / v), wherein v is the laser scanning speed, which ranges from 30 to 80 mm / s.

[0008] Furthermore, after step five is completed, a secondary balance test is performed, in which the rotation speed of the workpiece to be tested is 0.3n~0.6n. If the vibration sensor continues to detect centrifugal force vibration caused by imbalance, steps two to five are repeated.

[0009] Furthermore, the parameters of the laser generator meet the following requirements: pulse frequency 15-25 kHz, single pulse energy 2-5 mJ, focal spot diameter 0.2-0.5 mm, and protective gas flow rate 8-15 L / min.

[0010] Furthermore, the laser vaporization path adopts a spiral progressive removal trajectory with a pitch of 0.1~0.3mm.

[0011] Furthermore, the length of the circumference of the laser vaporized workpiece also includes the length of temperature drift compensation, and the calculation of the temperature drift compensation length satisfies: , where α is the thermal expansion coefficient of the workpiece being measured, and ΔT is the temperature change value of the processing area.

[0012] Furthermore, the rotation speed of the workpiece being measured is between 1000 and 2400 rpm.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The present invention implements synchronous laser vaporization de-weighting during the dynamic rotation of the workpiece being measured, and the delay from detecting data to executing instructions is reduced from 3-5 seconds to within 50ms, thereby eliminating the time for workstation transportation and secondary clamping, and avoiding the errors caused by workstation conversion, thereby ensuring the consistency of the dynamic balancing test benchmark. At the same time, this application supports assembly line operations of the same batch of workpieces being measured, which greatly improves the efficiency and accuracy of dynamic balancing detection.

[0014] Additional aspects and advantages of the present invention will be given in part in the description which follows, and in part will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0016] Figure 1 It is a flow chart of the single-station dynamic balancing method of the present invention. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The present invention is described in more detail. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween.

[0019] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, vertical, horizontal" and "top, bottom" are usually based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself. In the description of the present invention, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning, and therefore cannot be understood as limiting the scope of protection of the present invention. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0020] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0021] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0022] The preferred embodiments of the present invention are further described in conjunction with the accompanying drawings. Embodiment 1: like Figure 1 As shown, a single-station dynamic balancing method includes the following steps: The first step is to install the workpiece to be measured on the main shaft of the dynamic balancing machine to ensure that it is firmly fixed; install the laser generator and adjust the position of the laser generator to be perpendicular to the surface of the workpiece to be measured, and the distance meets the processing requirements; connect the laser generator to the speed sensor, vibration sensor and data acquisition system; we take the aluminum motor rotor as an example. The diameter and length of the motor rotor are set to 120mm and 250mm respectively, and the mass is 12kg. Install it on the main shaft of the dynamic balancing machine and keep its axial clamping force between 500-800N·m. Then aim the laser generator at the surface of the motor rotor, keep the distance between 1.2±0.1mm, and the vertical error between the optical axis and the surface of the motor rotor must be less than 0.05 degrees.

[0023] The second step is to drive the motor rotor to rotate at a uniform speed. After the speed stabilizes, the centrifugal force vibration caused by the imbalance is detected by a vibration sensor, so as to identify the imbalance position information of the motor rotor. The imbalance position information of the motor rotor includes the imbalance phase angle and the circumferential length of the imbalance position of the motor rotor calculated by the calculation.

[0024] The third step is to obtain the start time of detecting the imbalance and then confirm the continuous working time of the laser by calculation.

[0025] Step 4: Use dynamic compensation function Calculate the total balancing time, where T1 is the total balancing time, T0 is the start time when the imbalance is detected, n is the speed of the motor rotor, and Lc is the position information of the motor rotor imbalance.

[0026] The fifth step is to control the laser generator after confirming the above parameters, and implement synchronous laser vaporization de-weighting during the dynamic rotation of the motor rotor. The present invention reduces the delay from detecting data to executing instructions from 3-5 seconds to within 50ms by implementing synchronous laser vaporization de-weighting during the dynamic rotation of the workpiece being measured, eliminating the time for station handling and secondary clamping, and avoiding the errors caused by station conversion, ensuring the consistency of the dynamic balancing test benchmark. At the same time, this application supports the assembly line operation of the same batch of workpieces being measured, greatly improving the efficiency and accuracy of dynamic balancing detection.

[0027] Further on the basis of the above embodiment, in the step 2, the calculation of the circumferential length of the unbalanced position of the motor rotor satisfies the following formula: , where U is the unbalanced value in g·mm, ρ is the material density in g / mm³), A=single pulse gasification area, further, the calculation of U satisfies the following formula: U=(Avib⋅m) / Ks, where Avib is the vibration amplitude, Ks is the system stiffness coefficient, and m is the mass of the motor rotor. In this embodiment, after calculation, U is 11.3g⋅mm. Substitute 11.3g⋅mm into In the case of aluminum alloy, ρ=2.7g / cm³, single pulse area , the calculated L is 132.8mm.

[0028] Further on the basis of the above embodiment, in step 3, the calculation of the continuous working time of the laser satisfies the following formula: , where Tc is the continuous working time of the laser, L is the circumferential length of the unbalanced position of the motor rotor, in millimeters, and D is the diameter of the motor rotor. The initial speed n=1000rpm is set, and the above parameters are substituted into the calculation to obtain Tc of 12.6s. In addition, the initial detection time T0=0.06min=3.6s is calculated by T0=60 / n.

[0029] Further on the basis of the above embodiment, in step 4, the calculation of the total balance time satisfies the following formula: T1=1.3×(T0+Lc / v), wherein v is the laser scanning speed, which is 50 mm / s here, and the calculated value is 1.3*(3.6+(132.8 / 50))=8.13s.

[0030] Further on the basis of the above embodiment, in this embodiment, the pulse frequency is 20 kHz, the single pulse energy is 3 mJ, and the flow rate of the protective gas (nitrogen) is 12 L / min.

[0031] Further on the basis of the above embodiment, in this embodiment, the pitch is 0.15 mm and the laser scanning speed is 50 mm / s.

[0032] Further on the basis of the above embodiment, after the completion of step five, this embodiment can also perform a secondary balance test, the purpose of which is to detect whether the dynamic balance of the motor rotor meets the standard at a low speed. Specifically, the rotation speed of the motor rotor will be 0.3n~0.6n. If the vibration sensor continues to detect the centrifugal force vibration caused by imbalance, repeat steps two to five.

[0033] Further on the basis of the above embodiment, the circumferential length of the laser gasification motor rotor also includes the length for temperature drift compensation, and the calculation of the temperature drift compensation length satisfies: , where α is the thermal expansion coefficient of the motor rotor material and ΔT is the temperature change value of the processing area.

[0034] Embodiment 2 A single-station dynamic balancing method comprises the following steps: The first step is to install the workpiece to be measured on the spindle of the dynamic balancing machine to ensure that it is firmly fixed; install the laser generator and adjust the position of the laser generator to be perpendicular to the surface of the workpiece to be measured, and the distance meets the processing requirements; connect the laser generator to the speed sensor, vibration sensor and data acquisition system; we take a small stainless steel motor rotor as an example. The diameter and length of the motor rotor are set to 45mm and 60mm respectively. Install it on the spindle of the dynamic balancing machine and keep its axial clamping force between 500-800N·m. Then aim the laser generator at the surface of the motor rotor, keep the distance between 1.2±0.1mm, and the vertical error between the optical axis and the surface of the motor rotor must be less than 0.05°.

[0035] The second step is to drive the motor rotor to rotate at a uniform speed. After the speed stabilizes, the centrifugal force vibration caused by the imbalance is detected by a vibration sensor, so as to identify the imbalance position information of the motor rotor. The imbalance position information of the motor rotor includes the imbalance phase angle and the circumferential length of the imbalance position of the motor rotor calculated by the calculation.

[0036] The third step is to obtain the start time of detecting the imbalance and then confirm the continuous working time of the laser by calculation.

[0037] Step 4: Use dynamic compensation function Calculate the total balancing time, where T1 is the total balancing time, T0 is the start time when the imbalance is detected, n is the speed of the motor rotor, and Lc is the position information of the motor rotor imbalance.

[0038] The fifth step is to confirm the above parameters and control the laser generator to perform synchronous laser gasification and deweighting during the dynamic rotation of the motor rotor.

[0039] Further on the basis of the above embodiment, in the step 2, the calculation of the circumferential length of the unbalanced position of the motor rotor satisfies the following formula: , where U is the unbalanced value in g·mm, ρ is the material density in g / mm³), A=single pulse gasification area, further, the calculation of U satisfies the following formula: U=(Avib⋅m) / Ks, where Avib is the vibration amplitude, Ks is the system stiffness coefficient, and m is the mass of the motor rotor. In this embodiment, after calculation, U is 5.2g⋅mm, and 11.3g⋅mm is substituted into In the calculation, L is 20.7 mm.

[0040] Further on the basis of the above embodiment, in step 3, the calculation of the continuous working time of the laser satisfies the following formula: , where Tc is the continuous working time of the laser, L is the circumferential length of the unbalanced position of the motor rotor, in millimeters, and D is the diameter of the motor rotor. The initial speed n=2400rpm is set, and the above parameters are substituted into the calculation to obtain Tc of 0.21s. In addition, the initial detection time T0=0.01min=1.5s is calculated by T0=60 / n.

[0041] Further on the basis of the above embodiment, in step 4, the calculation of the total balancing time satisfies the following formula: T1=1.2×(T0+Lc / v), wherein v is the laser scanning speed, which is 60 mm / s here, and the calculated value is 1.2*(1.5+(20.7 / 60))=2.21 s.

[0042] Further on the basis of the above embodiment, in this embodiment, the pulse frequency is 17 kHz, the single pulse energy is 4 mJ, and the flow rate of the protective gas (nitrogen) is 9 L / min.

[0043] Further on the basis of the above embodiment, in this embodiment, the pitch is 0.25 mm and the laser scanning speed is 60 mm / s.

[0044] Further on the basis of the above embodiment, after the completion of step five, this embodiment can also perform a secondary balance test, the purpose of which is to detect whether the dynamic balance of the motor rotor meets the standard at a low speed. Specifically, the rotation speed of the motor rotor will be 0.3n~0.6n. If the vibration sensor continues to detect the centrifugal force vibration caused by imbalance, repeat steps two to five.

[0045] Further on the basis of the above embodiment, the circumferential length of the laser gasification motor rotor also includes the length for temperature drift compensation, and the calculation of the temperature drift compensation length satisfies: , where α is the thermal expansion coefficient of the motor rotor material and ΔT is the temperature change value of the processing area.

[0046] The details of the exemplary embodiments described above are not limited to the embodiments described above, and the invention may be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive in all respects, and the scope of the invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the invention.

Claims

1. A single-station dynamic balancing method, characterized in that: The following steps are involved: Step 1: Install the workpiece to be measured on the dynamic balancing machine and ensure that it is firmly fixed; install the laser generator and adjust the position of the laser generator to be perpendicular to the surface of the workpiece to be measured, and the distance meets the processing requirements; connect the laser generator to the speed sensor, vibration sensor and data acquisition system; Step 2: Drive the workpiece to be measured to rotate at a constant speed, and start the detection after the speed stabilizes. The centrifugal force vibration caused by the imbalance is detected by the vibration sensor to determine the imbalance position information of the workpiece to be measured; Step 3: Obtain the start time of detecting imbalance, and then confirm the continuous working time of the laser; Step 4: Use dynamic compensation function formula Calculate the total balancing time, where T1 is the total balancing time, T0 is the start time when the imbalance is detected, n is the rotation speed of the workpiece being measured, and Lc is the position information of the imbalance amount of the workpiece being measured; Step 5: Control the laser generator to perform synchronous laser vaporization and de-weighting during the dynamic rotation of the workpiece being measured.

2. The single-station dynamic balancing method according to claim 1, characterized in that: In step 3, the calculation of the laser continuous working time satisfies the following formula: , where Tc is the continuous working time of the laser, L is the circumferential length of the unbalanced position of the workpiece being measured, in millimeters, and D is the diameter of the workpiece being measured.

3. The single-station dynamic balancing method according to claim 1, characterized in that: In step 3, the calculation of the start time of detecting the imbalance satisfies the following formula: .

4. The single-station dynamic balancing method according to claim 1, characterized in that: In the step 4, the calculation of the total equilibrium time satisfies the following formula: T1=1.1~1.5×(T0+Lc / v), where v is the laser scanning speed, which ranges from 30~80 mm / s.

5. The single-station dynamic balancing method according to claim 1, characterized in that: The parameters of the laser generator meet the following requirements: pulse frequency 15-25 kHz, single pulse energy 2-5 mJ, focal spot diameter 0.2-0.5 mm, and protective gas flow rate 8-15 L / min.

6. The single-station dynamic balancing method according to claim 5, characterized in that: The laser vaporization path adopts a spiral progressive removal trajectory with a pitch of 0.1~0.3mm.

7. The single-station dynamic balancing method according to claim 2, characterized in that: The length of the circumference of the laser vaporized workpiece also includes the length of temperature drift compensation, and the calculation of the temperature drift compensation length satisfies: , where α is the thermal expansion coefficient of the workpiece being measured, and ΔT is the temperature change value of the processing area.

8. The single-station dynamic balancing method according to claim 1, characterized in that: The rotation speed of the workpiece to be measured is between 1000 and 2400 rpm.

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