Imbalance correction system, imbalance correction method, and imbalance correction program

Abstract

According to the present invention: an amount of imbalance of a workpiece is measured; a correction instruction amount for the workpiece is calculated on the basis of the measured amount of imbalance; imbalance correction is applied to the workpiece on the basis of the calculated correction instruction amount; and the correction instruction amount or a correction operation amount based on the correction instruction amount is adjusted such that a residual amount of imbalance remaining in the workpiece after the correction moves in a decreasing direction.

Description

Unbalance correction system, unbalance correction method, and unbalance correction program

[0001] The present invention relates to an unbalance correction system for correcting the amount of unbalance of a workpiece.

[0002] Conventional unbalance correction systems of this type calculate the correction amount so that the amount of unbalance of a workpiece measured by an unbalance measuring device such as that described in Patent Document 1 falls within the acceptance criteria, and then correct the workpiece using a machining jig such as a cutting drill based on the calculated value.

[0003] However, even if the unbalance can be corrected according to the calculated value at first, as the unbalance correction continues, the processing jig may wear out or the correction processing position may shift, making it impossible to correct the unbalance according to the calculated value, and the amount of unbalance remaining in the workpiece after correction may become large.

[0004] If the residual imbalance becomes too great, not only will something that was previously corrected to the pass standard with one correction need to be corrected two or three times, but some workpieces will still fail even after multiple corrections.

[0005] For this reason, a human must determine when the remaining unbalance in the workpiece after correction has become too large, and then use their experience and intuition to adjust the amount of unbalance correction, replace worn processing jigs, adjust their position, etc.

[0006] JP 2011-12611 A

[0007] The main objective of the present invention is to automatically suppress an increase in the amount of residual imbalance, thereby suppressing an increase in the number of times imbalance correction is required for a single workpiece, and further reducing the effort required for replacing and readjusting consumable parts.

[0008] That is, the unbalance correction system according to the present invention is characterized by comprising: a measurement mechanism that measures the amount of unbalance of a workpiece to be measured; a correction instruction amount calculation unit that calculates a correction instruction amount for the workpiece based on the amount of unbalance measured by the measurement mechanism; a correction mechanism that corrects the unbalance of the workpiece based on the correction instruction amount calculated by the correction instruction amount calculation unit; and an adjustment unit that adjusts the correction instruction amount or the amount of operation of the correction mechanism based on the correction instruction amount so that the amount of remaining unbalance in the workpiece that has been corrected by the correction mechanism tends to decrease.

[0009] With this configuration, it is possible to automatically suppress an increase in the amount of residual imbalance in the workpiece, which not only reduces the number of times imbalance correction is required for one workpiece, but also minimizes the need for part replacement and readjustment work that accompanies an increase in the amount of residual imbalance, and also shortens the time the system is shut down for these work.

[0010] It is an overall schematic diagram of an unbalance correction system according to an embodiment of the present invention. It is a flowchart showing an example of an operation of the unbalance correction system according to the embodiment. It is a vector diagram showing an example of a remaining unbalance amount according to the embodiment.

[0011] Hereinafter, an embodiment of the unbalance correction system 100 will be described with reference to the drawings. Note that in each drawing, some parts may be omitted or exaggerated as appropriate for ease of understanding.

[0012] 1, the unbalance correction system 100 in this embodiment measures the unbalance of a workpiece W that has undergone a predetermined manufacturing process, such as cutting, plating, or machining, and performs correction processing on the workpiece W so that the measured unbalance amount falls within an acceptable standard value. Note that the workpiece W here is a rotating body, such as a rotor, and has a long, columnar shape.

[0013] Specifically, this unbalance correction system 100 comprises a measurement mechanism 1 that measures the amount of unbalance of the workpiece W, a correction instruction amount calculation unit 2 that calculates a correction instruction amount for the workpiece W based on the amount of unbalance measured by the measurement mechanism 1, a correction mechanism 3 that performs unbalance correction on the workpiece W based on this correction instruction amount, and an adjustment unit 4 that adjusts the correction instruction amount so that the amount of remaining unbalance in the workpiece W that has been corrected by the correction mechanism 3 decreases.

[0014] Each part will be described in detail.

[0015] (1) Measuring mechanism The measuring mechanism 1 is of a dynamic balancing type and includes, for example, a bearing 111 on which both axial ends of the workpiece W are placed, a spring 112 that supports the bearing 111 so that it can be displaced freely, a belt 113 that is wound around the circumferential direction of the workpiece W, a motor 114 that drives and rotates the belt 113, a sensor unit 115 that detects the vibration of the bearing 111 and the rotation of the workpiece W, and an unbalance amount calculation unit 116 that calculates the amount of unbalance of the workpiece W based on the signal output by the sensor unit 115.

[0016] The sensor unit 115 includes a rotation detection sensor 115 a that detects the rotation of the workpiece W, and a vibration detection sensor 115 b that detects the vibration of the bearing 111 .

[0017] The rotation detection sensor 115a is provided in proximity to a mark M affixed to the outer peripheral surface of the workpiece W. When the workpiece W rotates, the rotation detection sensor 115a detects the mark M and outputs a signal whose phase reference is the point in time when the mark M is detected.

[0018] The vibration detection sensors 115b are of a moving coil type provided corresponding to each bearing 111. Specifically, when each bearing 111 vibrates in accordance with the rotation of the workpiece W, the vibration detection sensors 115b detect the displacement of each bearing 111 and output a sinusoidal signal corresponding to the displacement.

[0019] The unbalance amount calculation unit 116 calculates the amount of unbalance of the workpiece W based on the signals output by each sensor. More specifically, if an unbalance exists in the workpiece W, the bearing 111 vibrates as the workpiece W rotates, and the magnitude of vibration on the left and right surfaces of the workpiece W is calculated from the amplitude values ​​of the signals output by each vibration detection sensor 115b. The unbalance amount calculation unit 116 also calculates the phase angle on each of the left and right surfaces based on the phase relationship between the signal from the rotation detection sensor 115a and the signals from each vibration detection sensor 115b. In this embodiment, for example, the amount of unbalance is a multi-dimensional value including the magnitude of vibration on the left and right surfaces of the workpiece W, a phase angle indicating the angular difference between the maximum value of vibration on the left and right surfaces of the workpiece W and a phase reference, and the like, and can be expressed as a vector.

[0020] In this embodiment, a computer 5 equipped with a CPU, memory, input / output means, etc. is configured to function as the unbalance amount calculation unit 116 by installing a predetermined application on the computer 5.

[0021] (2) Correction instruction amount calculation unit The correction instruction amount calculation unit 2 applies a predetermined calculation algorithm to the imbalance amount calculated by the imbalance amount calculation unit, and calculates the correction instruction amount to be applied to the workpiece W in order to reduce the imbalance amount.

[0022] When the correction location on the workpiece W has been determined, the correction instruction amount will be a one-dimensional value represented by the resection weight (resection depth) or added weight at that location, but it may also be a vector represented by multiple dimensional values, such as a two-dimensional value represented by the correction location and the resection / addition weight.

[0023] In this embodiment, the computer 5 is configured to function as the correction instruction amount calculation unit 2 by installing a predetermined application in the computer 5 .

[0024] (3) Correction Mechanism The correction mechanism 3 corrects the imbalance of the workpiece W based on the correction instruction amount, and specifically includes a processing jig 31 (here, a cutting drill) and a drive control device 32 consisting of a servo motor or the like that drives and controls the processing jig 31, including its position and posture. The drive control device 32 acquires the correction instruction amount and operates the processing jig 31 by an amount of operation corresponding to the correction instruction amount.

[0025] (4) Adjustment Unit The adjustment unit 4 adjusts the correction instruction amount so as to reduce the amount of remaining unbalance in the workpiece W corrected by the correction mechanism 3. The adjustment unit 4 is configured so that its operation / non-operation can be switched by a switching signal, and here, the value of the switching signal is set by an input from the operator, so that the adjustment unit 4 can be switched between operation and non-operation.

[0026] In this embodiment, the computer 5 is configured to function as the adjustment unit 4 by installing a predetermined application on the computer 5 .

[0027] <Operation> Next, the operation of the unbalance correction system 100 when the adjustment unit 4 is set to the operating state by the switching signal will be described with reference to the flowchart in Fig. 2. First, the workpiece W is set in the measuring mechanism 1 (step S1), and the measuring mechanism 1 is operated.

[0028] As a result, the measuring mechanism 1 measures the amount of unbalance of the workpiece W (step S2).

[0029] Then, it is determined whether the amount of unbalance exceeds a predetermined reference value (step S3), and if it is equal to or less than the reference value, the workpiece W is determined to be balanced (passed), and the unbalance correction routine ends.

[0030] If not, the correction instruction amount calculation unit 2 calculates the correction instruction amount to be applied to the workpiece W based on the amount of unbalance measured by the measuring mechanism 1 (step S4).

[0031] Meanwhile, the workpiece W is transported to the correction mechanism 3 by a transport mechanism (not shown) (step S5).

[0032] Next, the drive control device 32 of the correction mechanism 3 acquires the correction instruction amount, and corrects the workpiece W by operating the machining jig 31 by an amount corresponding to the correction instruction amount (step S6).

[0033] Next, the workpiece W is transported again to the measuring mechanism 1 by the transport mechanism (step S7).

[0034] Next, the measuring mechanism 1 measures the amount of remaining unbalance in the workpiece W that has been subjected to unbalance correction processing (step S8).

[0035] Next, the adjusting unit 4 acquires the remaining unbalance amount and determines whether the amount exceeds a predetermined value (step S9).

[0036] The "predetermined value" referred to here is determined, for example, as follows. That is, when the workpiece W is corrected according to the correction instruction amount, the remaining unbalance amount falls within a predicted range including 0, which is determined by the machine precision. However, if the machining jig 31 wears out over time or the machining position shifts, a deviation occurs between the correction instruction amount and the actual correction amount, and the remaining unbalance amount exceeds the predicted range. The upper limit of the deviation that is allowed to a certain extent beyond the predicted range is determined as the predetermined value. This predetermined value is smaller than the reference value.

[0037] If it is determined that the remaining unbalance amount exceeds the predetermined value, the adjustment unit 4 corrects the calculation algorithm of the correction instruction amount calculation unit 2 in a direction that reduces the remaining unbalance amount (step S10).

[0038] 3 is a vector diagram illustrating the relationship between the unbalance amount before correction, the actual correction amount, and the remaining unbalance amount. In the diagram, the circles indicate predetermined values ​​on the vector diagram, and if the magnitude of the remaining unbalance amount exceeds this circle, the adjustment unit 4 corrects the calculation algorithm in the direction of reducing the remaining unbalance amount.

[0039] In the figure, (a) and (b) show cases where the actual correction amount is smaller than the correction instruction amount, and (c), (d), and (e) show cases where the actual correction amount is larger than the correction instruction amount. From these, it can be seen that if the angle difference between the unbalance before correction and the remaining unbalance is within ±90 degrees, the actual correction amount tends to be smaller than the correction instruction amount, but this is not the case when both the angle and the size are significantly different, as in figure (e).

[0040] In detail, the adjustment unit 4 compares the amount of unbalance before correction with the vector difference (actual correction amount) between the amount of unbalance before correction and the amount of remaining unbalance, and if the amount of unbalance before correction is larger, it determines that the initial correction instruction amount was too small, and if the amount of unbalance before correction is smaller, it determines that the initial correction instruction amount was too large.

[0041] If the initial correction instruction amount is too large, a correction is made by adding a decrease term (such as decreasing by XX% or subtracting by XX value) to the initial calculation algorithm, and if the initial correction instruction amount is too small, a correction is made by adding an increase term (such as increasing by XX% or increasing by XX value) to the initial calculation algorithm.

[0042] This adjusts the correction instruction amount by the correction instruction amount calculation unit 2. Although not shown in the flowchart, if the remaining unbalance amount exceeds a reference value, the workpiece W is returned to the correction mechanism 3 and is corrected again based on the adjusted correction instruction amount.

[0043] Other Embodiments Next, other embodiments will be described.

[0044] In the above embodiment, the adjustment unit was configured so that an operator could instruct it to switch between operating and non-operating states, but the conditions for switching the adjustment unit from a non-operating state to an operating state can be set, for example, every certain period of time or when the imbalance amount exceeds the reference value a predetermined number of times in succession, and the adjustment unit can be automatically switched from a non-operating state to an operating state by a computer.

[0045] Furthermore, the condition for switching the adjustment unit from an operating state to a non-operating state may be such that the remaining unbalance amount is measured after correcting the unbalance of the workpiece or the next workpiece using the correction instruction amount in the calculation algorithm corrected by the adjustment unit, and the adjustment unit is placed in a non-operating state if the remaining unbalance amount becomes equal to or less than the predetermined value.Otherwise, the adjustment unit may be switched from an operating state to a non-operating state if the state in which the unbalance amount satisfies the reference value occurs a predetermined number of times in succession.

[0046] According to the above configuration, the operation of the adjustment unit can be minimized, and the operating efficiency of the unbalance correction system can be improved.

[0047] If the amount of adjustment by the adjustment unit (in the above embodiment, the amount of correction of the calculation algorithm) or the frequency of operation of the adjustment unit exceeds a certain level, it may be determined that software compensation by the adjustment unit is difficult, and an alarm signal may be output to prompt replacement of parts of the correction mechanism or readjustment.

[0048] According to the above configuration, unnecessary part replacement or readjustment can be prevented, and the operating efficiency of the unbalance correction system can be improved.

[0049] In the above embodiment, the adjustment unit corrects the calculation algorithm of the correction instruction amount calculation unit, but it may also correct the operation amount output by the correction mechanism.

[0050] The computer in the above embodiment does not need to be physically integrated, but may be composed of multiple computer units that can communicate with each other, or some or all of them may be cloud computers, or may be installed in a location separate from the device itself.

[0051] Furthermore, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications are possible without departing from the spirit of the present invention. <Summary> The features of the above-described configuration can be summarized as follows.

[0052] [1] An unbalance correction system comprising: a measurement mechanism that measures the amount of unbalance of a workpiece to be measured; a correction instruction amount calculation unit that calculates a correction instruction amount for the workpiece based on the amount of unbalance measured by the measurement mechanism; a correction mechanism that corrects the unbalance of the workpiece based on the correction instruction amount calculated by the correction instruction amount calculation unit; and an adjustment unit that adjusts the correction instruction amount or an amount of operation of the correction mechanism based on the correction instruction amount so that the amount of remaining unbalance in the workpiece corrected by the correction mechanism tends to decrease.

[0053] With this configuration, it is possible to automatically suppress an increase in the amount of residual imbalance in the workpiece, which not only reduces the number of times imbalance correction is required for one workpiece, but also minimizes the need for part replacement and readjustment work that accompanies an increase in the amount of residual imbalance, thereby improving the operating efficiency of the imbalance correction system.

[0054] [2] The unbalance correction system according to [1], wherein the adjustment unit is configured to be switchable between an operating state and a non-operating state. With this configuration, operation of the adjustment unit in unnecessary situations can be suppressed, thereby improving the operating efficiency of the unbalance correction system.

[0055] [3] The unbalance correction system according to [1] or [2], wherein the adjustment unit adjusts the correction instruction amount or the operation amount of the correction mechanism based on the correction instruction amount only when the remaining unbalance amount exceeds a predetermined value. With this configuration, the operation amount of the correction mechanism is adjusted only when necessary, thereby optimizing the operating efficiency of the unbalance correction system.

[0056] [4] An unbalance correction system according to any one of [1] to [3], wherein the measurement mechanism includes a vibration detection sensor and a rotation detection sensor, and the adjustment unit compares the unbalance amount before correction with an actual correction amount which is the difference between the unbalance amount before correction and the remaining unbalance amount, and determines that the initial correction instruction amount was too small if the unbalance amount before correction is larger, and determines that the initial correction instruction amount was too large if the unbalance amount before correction is small.

[0057] With this configuration, the unbalance amount before correction is compared with the actual correction amount, so it is possible to accurately determine whether the correction instruction amount was too large or too small. As mentioned above, the "amount" is expressed as a vector including multidimensional values, and the "difference in amount" refers to the difference between vectors.

[0058] Since the increase in the residual imbalance of the workpiece can be automatically suppressed, not only can the number of times imbalance correction is required for one workpiece be reduced, but part replacement and readjustment work that accompanies an increase in the residual imbalance can also be reduced as much as possible, and the time the system is stopped for these work can also be shortened.

[0059] 100... Unbalance correction system 1... Measurement mechanism 2... Correction instruction amount calculation unit 3... Correction mechanism 4... Adjustment unit W... Workpiece

Claims

1. a measurement mechanism for measuring the amount of imbalance of a workpiece to be measured; a correction instruction amount calculation unit that calculates a correction instruction amount for the workpiece based on the unbalance amount measured by the measurement mechanism; a correction mechanism that corrects unbalance of the workpiece based on the correction instruction amount calculated by the correction instruction amount calculation unit; an adjustment unit that corrects the calculation algorithm of the correction instruction amount calculation unit or adjusts the operation amount of the correction mechanism based on the correction instruction amount so that the amount of remaining unbalance in the workpiece that has been corrected by the correction mechanism tends to decrease when a discrepancy occurs between the correction instruction amount and the actual correction amount due to wear or positional deviation of the correction mechanism over time.

2. 2. The unbalance correction system according to claim 1, wherein the adjustment unit is configured to be switchable between an operating state and a non-operating state.

3. 2. The unbalance correction system according to claim 1, wherein the adjustment unit determines whether the magnitude of the remaining unbalance amount measured by the measurement mechanism is greater than a predetermined value, and when it determines that the remaining unbalance amount is greater than the predetermined value, adjusts the correction instruction amount or an operation amount of the correction mechanism based on the correction instruction amount.

4. the measurement mechanism includes a vibration detection sensor and a rotation detection sensor, 2. The unbalance correction system according to claim 1, wherein the adjustment unit compares the pre-correction unbalance amount with an actual correction amount which is the difference between the pre-correction unbalance amount and the remaining unbalance amount, and determines that the initial correction instruction amount was too small if the pre-correction unbalance amount is larger, and determines that the initial correction instruction amount was too large if the pre-correction unbalance amount is small.

5. A measurement mechanism for measuring the amount of imbalance of a workpiece to be measured; a correction instruction amount calculation unit that calculates a correction instruction amount for the workpiece based on the unbalance amount measured by the measurement mechanism; a correction mechanism that corrects unbalance on the workpiece based on the correction instruction amount calculated by the correction instruction amount calculation unit, An unbalance correction method characterized by correcting the calculation algorithm of the correction instruction amount calculation unit or adjusting the operating amount of the correction mechanism based on the correction instruction amount so that the residual unbalance amount remaining in the workpiece corrected by the correction mechanism tends to decrease when a discrepancy occurs between the correction instruction amount and the actual correction amount due to wear or positional deviation of the correction mechanism over time.

6. A program applied to an unbalance correction system including a measurement mechanism for measuring an amount of unbalance of a workpiece to be measured and a correction mechanism for correcting the unbalance of the workpiece, a correction instruction amount calculation unit that calculates a correction instruction amount for the workpiece based on the unbalance amount measured by the measurement mechanism and outputs the calculated amount to the correction mechanism; An unbalance correction program characterized by causing an unbalance correction system to function as an adjustment unit that corrects the calculation algorithm of the correction instruction amount calculation unit or adjusts the operating amount of the correction mechanism based on the correction instruction amount so that the remaining unbalance amount in a workpiece that has been corrected in accordance with the correction instruction amount tends to decrease when a discrepancy occurs between the correction instruction amount and the actual correction amount due to wear or positional deviation of the correction mechanism over time.