JP2938085B2 - Unbalance correction method and unbalance correction device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unbalance correcting method and an unbalance correcting apparatus, and more particularly to a method and an apparatus suitable for correcting an unbalance such as an asymmetric crankshaft. is there.

<Conventional Technology> A crankshaft has a limited angle range that can be corrected due to its structure. That is, only the counterweight portion of the crankshaft can be corrected, and usually, the counterweight is corrected by drilling a hole in the radial direction or cutting by milling.

For this reason, if the direction of the unbalance is out of the range of the counter weight in a certain counter weight, it is not possible to drill a hole in the counter weight, and the unbalance is corrected by another counter weight. By removing it.

For example, taking the crankshaft of a four-cylinder engine as an example, the four counterweights are provided in plane symmetry with respect to the longitudinal section at the center point of the center journal (the center in the counterweight arrangement direction). Thus, adding or removing the same amount of unbalance for all counterweights has no effect on the overall crankshaft unbalance. Therefore, if the direction of the unbalance at a certain counter weight is out of the range of the counter weight, a simple addition will add a calculated unbalance to the four counter weights, and the four counter weights will be unbalanced. Were all within the range that can be corrected.

However, when the crankshaft does not have a symmetric shape like the crankshaft of the above-described four-cylinder engine and has an asymmetric shape, the above simple calculation cannot be applied, and it is difficult to correct the counterweight. Was.

Here, the asymmetric crankshaft is a crankshaft in which the position of each counterweight provided on the crankshaft is not in a plane-symmetric position with respect to the central longitudinal section in the counterweight arrangement direction. For example, a crankshaft of a three-cylinder or five-cylinder engine, a crankshaft of a V-type eight-cylinder engine, and the like are often asymmetric crankshafts.

Therefore, conventionally, the unbalance correction of the asymmetric crankshaft is performed when the direction of the unbalance in the counter weight to be corrected is out of the range of the counter weight, that is, when the amount of the unbalance becomes negative, as follows. Corrections were made by the procedure.

That is, in the unbalance measurement, the counterweights at the left and right ends are normally used as the balance surface, and the so-called component force measurement is performed. Not in any direction). However, if any of the V component or H component becomes negative, it is impossible to correct the imbalance with the counter weight. In such a case, the operator appropriately selects the inner counter weights other than the left and right ends and appropriately corrects the counter weights by taking into account the counter weights so that the V component and the H component on the left and right balancing surfaces are all positive. Was.

This is because, in the case of an asymmetric crankshaft, unlike a symmetrical crankshaft such as a four-cylinder engine crankshaft, if the same amount of imbalance is added or removed from all the counterweights, the entire crankshaft is reduced. The balance goes wrong. Therefore, it is difficult to simply change the unbalance in calculation, and conventionally,
As described above, it relied on the intuition of the worker.

In addition, when performing the correction with the automatic correction device, the initial unbalance of the crankshaft is controlled in the pre-processing step so that the angle is within the correctable angle range of the counter weights at the left and right ends. If the angle of the counterweight is out of the range that can be corrected, the crankshaft is dispensed from the line of the correction process as uncorrectable, and hand correction based on the intuition of the operator was performed as described above. .

<Problems to be Solved by the Invention> As described above, in the unbalance correction of the asymmetrical crankshaft, if the unbalance in the balancing surface is out of the correctable range, the unbalance is performed depending on the intuition of the operator. Is within the angle range that can be corrected, so that there is a drawback that it is difficult for a skilled worker to make corrections, and that work efficiency is not good.

In addition, when using the automatic correction device, the initial unbalance of the crankshaft must be managed in the pre-processing step so as to be within the correctable angle range of the counter weights at the left and right ends, and the crankshaft mold or Very high precision is required for the centering device and the like.

Furthermore, in the pre-processing step, a considerable amount of unbalance is intentionally left within the range where the balancing surface can be corrected, and when the unbalance is corrected, a hole is drilled in the counterweight to correct the unbalance. In this method, a considerable amount of cutting must be performed with a drill or the like, and the characteristics of the crankshaft itself may be impaired.

The problem to be solved by the invention as described above is not only the unbalance correction in the asymmetric crankshaft, but also in the case of other test specimens in which the angle range that can be corrected is limited. Exists.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for correcting unbalance in an asymmetric crankshaft, which can efficiently and quickly perform the unbalance correction.

<Means for Solving the Problems> The present invention is directed to an asymmetrical crankshaft in which the positions of a plurality of counterweights provided on the crankshaft are not plane-symmetric with respect to the central longitudinal section in the counterweight arrangement direction. An unbalance correction method, in which an arbitrary counter weight is determined as a main correction plane, another counter weight is determined as an auxiliary correction plane, an unbalance in the main correction plane is measured, and the measured unbalance is determined as a first correction plane. A determination is made as to whether or not all of the unbalances stored in the first storage unit can be corrected by the main correction plane. If there is an uncorrectable unbalanced component, the uncorrectable component is determined. Correction correction data for correcting the auxiliary correction surface in order to cancel the unbalanced component, and storing the calculated correction data in the second storage means, and correcting the auxiliary correction surface based on the calculation correction data If the unbalance of the main correction surface stored in the first storage means is affected as a result of the above operation, a new unbalance obtained by vector synthesis of the influence to the original unbalance of the main correction surface is applied to the main correction surface. Is updated and stored in the first storage means as the imbalance of
A determination is made as to whether all of the unbalances updated and stored in the storage means can be corrected on the main correction surface, and until the unbalance updated and stored in the first storage means contains no uncorrectable unbalanced components. The above-mentioned and the above-mentioned processing are repeated, and the unbalance correction updated and stored in the first storage means and the correction data which are cumulatively stored in the second storage means are obtained. This is a method for correcting imbalance, which is performed.

Further, according to the present invention, in the unbalance correcting method according to the first aspect, when a plurality of counter weights different from the counter weight determined on the main correction surface are determined on the auxiliary correction surface, and the above-described processing is performed, a plurality of auxiliary weights are determined. For the correction surface,
In each case, calculation correction data to be corrected to cancel the uncorrectable unbalanced component of the main correction surface is obtained, and the calculation correction data selects an appropriate auxiliary correction surface, and the selected auxiliary correction surface is selected. Is stored in the second storage means.

Still further, the present invention is an apparatus for correcting an unbalance for an asymmetric crankshaft in which the positions of a plurality of counterweights provided on the crankshaft are not plane-symmetric with respect to the central longitudinal section in the counterweight arrangement direction. Means for setting an arbitrary counter weight as the main correction plane and setting another counter weight as the auxiliary correction plane; first storage means for storing the measured unbalance in the main correction plane; Second storage means for storing correction data calculated on the auxiliary correction surface;
It is determined whether or not all of the measured unbalances stored in the first storage means can be corrected by the main correction surface. If there is an uncorrectable unbalanced component, the uncorrectable unbalance is determined. Processing means for obtaining and storing in the second storage means calculated correction data for correcting the auxiliary correction surface in order to cancel the component; and a result of correcting the auxiliary correction surface based on the calculation correction data If the unbalance of the main correction surface stored in the first storage means is affected, a new unbalance obtained by vector-combining the influence to the original unbalance of the main correction surface is regarded as the unbalance of the main correction surface. The processing means for updating and storing the data in the first storage means and a determination as to whether or not all of the unbalances updated and stored in the first storage means can be corrected on the main correction surface, and the updated and stored information is stored in the first storage means. Unbalanced components that cannot be corrected Processing repetition means for repeating the above-mentioned processing until it disappears, and the unbalance updated and stored in the first storage means and the correction data cumulatively stored in the second storage means obtained by repeating the above-mentioned processing. And an unbalance correcting means for performing the unbalance correction based on the following.

<Operation> When an uncorrectable unbalance component is included, such as when the unbalance on the main correction surface is out of the correctable angle range, the auxiliary correction surface is used to cancel the uncorrectable unbalance component. Obtain calculation correction data to be corrected. In this case, when there are a plurality of auxiliary correction planes, calculation correction data for each auxiliary correction plane is obtained, and the auxiliary correction plane of the most appropriate correction data is used.

Then, if the correction based on the calculation correction data is performed on the auxiliary correction surface, the imbalance of the main correction surface should be affected, so the imbalance of the main correction surface after the influence is corrected. Obtained by calculation. This calculation is performed by performing vector synthesis of the influence when the auxiliary correction surface is corrected to the original unbalance of the main correction surface. As a result, the new unbalance obtained by the vector synthesis is regarded as the unbalance of the main correction surface, and it is determined whether or not all the unbalance can be corrected by the main correction surface. If all of the unbalances cannot be corrected by the main correction surface and further includes an uncorrectable unbalance component, the calculation correction data for canceling the uncorrectable unbalance component is added to the auxiliary correction surface. Ask above. Similarly, when the calculated correction data is applied to the auxiliary correction surface, the influence of the imbalance of the main correction surface is vector-combined with the imbalance of the main correction surface.

By repeating this process in the calculation, finally, all the imbalances in the main correction surface can be corrected in the main correction surface, and the calculation correction data in the auxiliary correction surface is accumulated.

The correction is performed based on the obtained results. That is, on the main correction surface, a correction for removing the unbalance is performed, and on the auxiliary correction surface,
A correction based on the accumulated correction data is performed.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

As a specific example, a description will be given of a method for correcting imbalance when the test object is an asymmetric crankshaft of a five-cylinder engine.

In the crankshaft of a five-cylinder engine, the portion where the unbalance can be corrected is a portion of five counterweights. In the crankshaft of the five-cylinder engine for which unbalance correction is to be performed in this embodiment, as shown in a development view of FIG. 1, counter weights 1, 2, 3, 4, and 5 are arranged at equal intervals. And are provided so as to have an angle difference of 72 degrees in order. Therefore, the five counter weights 1, 2, 3, 4, 5 are not plane-symmetric with respect to the central longitudinal section in the counter weight arrangement direction. That is, it is an asymmetric crankshaft.

In this embodiment, the asymmetric crankshaft is measured for unbalance according to the following procedure, and the unbalance is corrected.

First, using the counterweights 1 and 5 at the left and right ends of the crankshaft as the balancing surfaces, the unbalance on the balancing surfaces is measured. In this embodiment, the unbalance measurement is performed by a component force measurement at a decomposition angle of 60 degrees.
The measurement other than the component force measurement may be performed.

As a result, 0 degrees (hereinafter, referred to as counter weight 1)
The angle in the description is, in principle, an absolute angle expressed with reference to a predetermined direction. ) Direction, H1 in the 60 degree direction,
In the counterweight 5, an unbalanced component force component of V5 in the direction of 288 degrees and H5 in the direction of 348 degrees is measured. Therefore,
These measured component force components V1, H1 and V5, H5 are stored in the storage means.

In the following description, these component components V1, H1 or V1
The counterweight 1 or 5 having 5, H5 will be referred to as the main correction surface 1 or 5, respectively.

The main correction surface may be selected from the counter weights 2, 3, and 4 instead of the counter weights 1 and 5.

Next, the angles 0 degrees of the above four component components V1, H1, V5, H5,
For 60 degrees, 288 degrees, and 348 degrees, the counter weights in which the angle positions in the opposite directions having an angle difference of 180 degrees are within the correctable range, respectively, and the remaining three counter weights 2,
The counter weight is selected from 3, 4 and the selected counter weight is set as the unbalanced auxiliary correction surface 2, 3, 4.

In the case of this embodiment, the counterweight 3 in which the angle of 180 degrees is included in the modifiable range for the component force component V1 of the angle of 0 degree is 240 degrees for the component force component H1 of the angle of 60 degrees. Is included in the correctable range,
The counterweight 4 in which the angle of 108 degrees is included in the modifiable range for the component force component V5 having an angle of 288 degrees, and the angle of 168 degrees is included in the modifiable range for the component force component H5 having an angle of 348 degrees. The respective counter weights 3 are selected as auxiliary correction surfaces.

Unlike the case of this embodiment, when the angular position separated by 180 degrees from the angle of the component force component V1 or H1 or V5 or H5 on the main correction surface 1 or 5 does not exist as a correctable range in any counter weight, Alternatively, a counterweight whose angular position close to the angular position is within the correctable range may be selected as the auxiliary correction surface.

Further, the counter weight selected as the auxiliary correction plane is the component force component V1 or H1 in the main correction plane 1 or 5.
Or, a counterweight whose angle range having an arbitrary angle difference such as the component force component V1 or H1 or the angle of V5 or H5 is a correctable range without having to have an angular position separated by about 180 degrees from the angle of V5 or H5. You may choose.

Furthermore, even when the unbalance measurement on the main correction surface 1 or 5 is measured not by the component force measurement but by the null method, for example, the angle position of the unbalance on the main correction surface 1 or 5 is almost 180 degrees. A counterweight whose separated angular position is within the correctable range may be selected as the auxiliary correction surface, or a counterweight having an arbitrary angular difference from the unbalanced angular position in the main correction front surface 1 or 5 is used as the auxiliary correction surface. You may choose.

In some actual crankshafts, each of the counterweights 1 to 5 is configured as a pair of two. In this case, the intermediate position in the axial direction of the pair of counterweights is a correction surface for calculation.

Further, the correction plane in calculation need not be directly related to the counterweight position, and can be arbitrarily selected as long as the position is clearly defined. Therefore, the correction plane in calculation may be a convenient position when allocating the unbalance to the actual counterweight.

When all the component components V1 and H1 on the main correction surface 1 and the component components V5 and H5 on the main correction front 5 are not negative, that is, all the component components V1, H1, stored in
When V5 and H5 are positive or zero, their component components V1, H1, V5,
Drill holes at 0 ° and 60 ° of the main correction surface 1 and at 288 ° and 348 ° of the main correction surface 5 with H5 as the correction amount, and adjust the corresponding correction amounts V1, H1, V5, Or cut H5 and correct the imbalance.

Note that the correction angle position on the main correction surface 1 is not two angles, that is, the angle 0 degree and the angle 60 degrees as described above, but the vector synthesis is performed with the correction amount V1 at the angle 0 degree and the correction amount H1 at the angle 60 degrees. Thus, the angle position to be corrected and the correction amount may be obtained, and the angle position may be corrected. The unbalance correction on the main correction surface 5 may be performed by a similar method.

On the other hand, the component components V1, H1,
If there is at least one negative component component of V5 and H5, a negative component component is added to the auxiliary correction surface corresponding to the negative component component so that the component component does not become negative. A calculated correction amount is obtained at an angular position separated by 180 degrees, and the obtained correction amount is stored in the storage means.

For example, when the component force component V1 becomes negative, the negative component force component V1 is set at a position at an angle of 180 degrees on the auxiliary correction surface 3.
A correction amount H3 for canceling (making it positive or zero) is calculated. If the component force component H1 is negative, the negative component component H
A correction amount M2 for canceling 1 is calculated. Further, when the component force component V5 on the main correction surface 5 is negative, a correction amount M4 for canceling the negative component force component V5 at a position at an angle of 108 degrees on the auxiliary correction surface 4 is obtained. Also,
If the component component H5 is negative, the angle at the auxiliary correction surface 3
At the position of 168 degrees, a correction amount V3 for canceling the negative component force component H5 is obtained.

It should be noted that, instead of calculating the correction amount at an angle position 180 degrees apart from the angle position of the negative component component on the main correction surface 1 or 5, the angle position is decomposed into a plurality of angle positions and the decomposition is performed. The correction amounts at the respective angular positions may be calculated.

Then, based on the amount of correction, the auxiliary correction surface 2, 3, 4
If the component components V1, H1 or V5, H5 on the main correction surface 1 or 5 are affected as a result of the computational correction in, the component component V1, H1 or V5 based on the effect component , H5, and the result is set as a new component component V1, H1 or V5, H5 on the main correction surface 1 or 5.

Similarly, when a calculation correction is performed on one auxiliary correction surface based on the correction amount, the correction amount M2, H3, V3 or M4 on any of the other auxiliary correction surfaces is affected. Is vector-combined with the original correction amount, and the result is used as the new correction amount M2, M
3a, M3b or M4.

The above-mentioned processing and the above-mentioned processing are performed so that the component force components V1, H1 and V5, H5 on the main correction surfaces 1 and 5 and the correction amounts M2, M3a, M3b, M4 on the auxiliary correction surfaces 2, 3, 4 are all positive or zero. Repeat until:

However, if it is not possible to get out of this processing loop indefinitely, when a predetermined condition is reached, for example, when the processing is repeated a predetermined number of times or when a predetermined time has elapsed when processing is performed by a computer Forcibly exit this processing loop,
The crankshaft being processed at that time is an uncorrectable crankshaft.

Component amounts V1, H1, V5, H5 on the main correction surfaces 1, 5 and the correction amounts on the auxiliary correction surfaces 2, 3, 4 finally obtained in
Let M2, H3, V3, and M4 be the correction amounts for each surface.

In this embodiment, 2 in the auxiliary correction surface 3
Instead of using the two correction amounts H3 and V3 as separate correction amounts, the vector is finally synthesized to obtain one correction amount M3 and an angle.

The counterweights 1, 2, 3, 4, and 5 are cut or corrected by a drill or the like or milled based on the correction amounts on the correction surfaces obtained as described above.

Next, an example of a specific correction amount calculation method in the above-described embodiment will be described.

It is assumed that the decomposition angle of the component force measurement on the main correction surfaces 1 and 5 is P degrees.

Step S1: Initialization of data and calculation of calibration coefficient Data initialization; M2 = V3 = H3 = M4 = 0 Calculation of calibration coefficient; K1 = −SIN (72 ゜ −P ゜)) / SIN (P ゜) K2 = SIN (108 ゜) / SIN (P ゜) K3 = −SIN (72 ゜) / SIN (P ゜) / 3 K4 = SIN (108-P ゜) / SIN (P ゜) / 3 C1 = 2 C2 = 4 / 3 However, the angle of M2 is 180 degrees opposite to the angle of H1 The angle of V3 is 180 degrees opposite to the angle of H5 The angle of H3 is 180 degrees opposite to the angle of V1 The angle of M4 is 180 degrees opposite to the angle of V5 V5 is when the condition that the distance between adjacent correction planes that are 288 degrees apart is equal is satisfied. Here, each calibration coefficient has the following significance.

K1: Calibration coefficient considering the unbalance among the component force component V1 on the main correction surface 1, the component force component V5 on the main correction surface 5, and the correction amount H3 on the auxiliary correction surface 3, or the main repair Calibration coefficient K2 taking into account the effect of imbalance among component force component H1 at front 1, component force component H5 at correction surface 5 and correction amount V3 calculated at auxiliary correction surface 3 K2: Component force component at main correction surface 1 V1, the component force component V5 in the main correction surface 5, and the correction amount V3 in the auxiliary correction surface 3 or the calibration coefficient K3 that takes into account the effect of imbalance between H3: K3: the component force component H1 in the main correction surface 1, Calibration coefficient K4 taking into account the effect between component force component V5 on correction surface 5 and calculation correction amount M2 on auxiliary correction surface 2 or calculation correction amount M4 on auxiliary correction surface 4 K4: Component force on main correction surface 1 Component V1, component force component V5 on main correction surface 5 Or a component coefficient taking into account the effect of the calculation correction amount M4 on the auxiliary correction surface 4 or the component force component H1 on the main correction surface 1, the component force component H5 on the main correction surface 5, and the calculation on the auxiliary correction surface 2 Calibration coefficient C1 taking into account the influence between the above correction amounts M2, C1: when V1 <0, an unbalanced calibration coefficient required to obtain a correction amount H3 for setting V1 = 0 on the auxiliary correction surface 3, or , H5 <0, H5 on the auxiliary correction surface 3
Unbalanced calibration coefficient C2 required to find the correction amount V3 for setting = 0, and when H1 <0, the unbalanced calibration coefficient C2 required for finding the correction amount M2 for setting H1 = 0 on the auxiliary correction surface 2 is obtained. The calibration coefficient of the balance, or when V5 <0, V5
Unbalanced calibration coefficient required to find the correction amount M4 for setting = 0 Step S2: When V1 <0, the following processing is performed.

 V1 = 0 Q = -V1 H3 = H3 + C1 × Q V5 = V5 + K1 × Q H5 = H5 + K2 × Q Step S3: When H1 <0, the following processing is performed.

 H1 = 0 Q = -H1 M2 = M2 + C2 × Q V5 = V5 + K3 × Q H5 = H5 + K4 × Q Step S4: When V5 <0, the following processing is performed.

 V5 = 0 Q = -V5 M4 = M4 + C2 × Q V1 = V1 + K4 × Q H1 = H1 + K3 × Q Step S5: When H5 <0, the following processing is performed.

H5 = 0 Q = -H5 V3 = V3 + C1 × Q V1 = V1 + K2 × Q H1 = H1 + K1 × Q Step S6: If all of V1, H1, V5, H5, V3, H3, M4 are not negative, or one of them is negative However, if the time limit for calculation is exceeded, the process proceeds to the next step S7.

Otherwise, the process returns to step S2. Step S
7: If all of V1, H1, V5, M2, H5, V3, H3, and M4 are not negative, V3 and H3 are vector synthesized to obtain a correction amount M3 and its angle.

If any of V1, H1, V5, H5, M2, V3, H3, M4 is negative,
It cannot be modified.

In the specific example described above, an example of the unbalance-correctable range of the counterweight 1 when the disassembly angle P = 50 degrees is shown in FIGS. 2 and 3, and an example of the unbalance-correctable range of the counterweight 5 is shown. Is shown in FIG.

In FIGS. 2 and 3, the range shown by the solid line is the range in which the unbalance of the counter weight 1 can be corrected (the unbalance position of the counter weight 5 is different between FIGS. 2 and 3). , Counter weight 1
It is different from the imbalance correction range. ). The range indicated by the dashed line is the range in which the counterweight 1 can be unbalance corrected when the auxiliary correction surface is not used.

Similarly, FIG. 4 shows an example of the range in which the unbalance correction of the counter weight 5 is possible when the auxiliary correction surface is not used (1).
Indicated by a dotted line. ) Is indicated by a solid line.

From FIGS. 2 to 4, it can be seen that according to this embodiment, the range in which the counterweights 1 and 5 as the main correction surface can be corrected unbalance is widened greatly.

FIG. 5 is a block diagram showing an example of a circuit configuration of an apparatus for calculating the above-described asymmetrical crankshaft unbalance correction amount. FIG. 6 is a block diagram showing a conventional method for correcting unbalance correction. FIG. 3 is a block diagram of a circuit configuration example of a device for calculating an amount.

As is clear from the comparison between FIG. 5 and FIG. 6, in the circuit of this embodiment, the main correction surface 1,
The component force components V1, H1, V5, H5 measured at 5 are not directly output values as they are, but the output values are
Is to be given. The calculation circuit 12 is configured by a microcomputer including, for example, a CPU, a ROM, and a RAM. In the ROM, for example, an operation program (steps S1 to S1) for calculating the above-described unbalance correction amount and angle is provided. Step S7) is stored.
The calculation circuit 12 performs calculations in accordance with this operation program, and calculates the component force components V1, H1, V5, H5 in the main correction surfaces 1, 5 and the M2, H in the auxiliary correction surfaces 2, 3, 4 in consideration of the calibration coefficient and the like.
Calculate 3, V3, M4 and output it.

In FIGS. 5 and 6, reference numeral 13 denotes a main correction surface.
Reference numeral 14 denotes a vibration detector for measuring the unbalance in 1 and 5, and reference numeral 14 denotes a reference phase detector for obtaining a rotation reference signal. The arithmetic circuit 11 measures and calculates the unbalance on the main correction surfaces 1 and 5 from the vibration detector 13 and the reference phase detector 14 by a method conventionally known in the field of dynamic balance testing machines.

In the above embodiment, the unbalance on the main correction surfaces 1 and 5 is obtained by the component force measurement, and the correction amount M2 on the auxiliary correction surface 2 is obtained.
The correction amount M4 on the auxiliary correction surface 4 is obtained by obtaining the correction amount at a predetermined fixed angle, and the auxiliary correction surface 3 is obtained by obtaining the correction amounts V3 and H3 by the force component method. As with each deformation, the amount of correction on each correction plane can be determined by any method.

That is, the unbalance measurement on the main correction surfaces 1 and 5, the final correction amount on the main correction surfaces 1 and 5, and the correction amounts on the auxiliary correction surfaces 2, 3 and 4 are all obtained by the component force method. The amount of correction on the correction surfaces 1 and 5 uses the component force method, and the amount of correction on the auxiliary correction surfaces 2, 3 and 4 calculates the amount of correction at a predetermined fixed angle. The auxiliary correction surfaces 2 and 4 determine the correction amount at a predetermined fixed angle, and the auxiliary correction surface 3 determines the correction amount and angle by the null method. Various changes such as obtaining the correction amount and the angle by the null method on all the correction surfaces 2, 3, and 4 are possible.

Which method is used to determine the imbalance may be arbitrarily combined.

Further, in the above description of the embodiment, the case where the unbalance of the asymmetric crankshaft is removed by one correction operation has been described. However, when the unbalance correction is performed more precisely, it is referred to as rough correction and finish correction. The correction may be performed in two correction operations. The present invention can be applied to the case where such two corrections are performed. Next, a specific example in which two correction operations are performed will be briefly described.

Processing for rough correction: Unbalanced component component V measured on main correction surfaces 1 and 2
For each of 1, H1, V5, and H5, an offset process of reducing the constant ΔU is performed. That is, V1 = V1−ΔU H1 = H1−ΔU V5 = V5−ΔU H5 = H5−ΔU This process is a process for shortening the time of the finish correction by making the unbalanced angular position remain in the correctable range of the main correction surfaces 1 and 5 at the time of the next finish correction.

Next, based on the component components V1, H1, V5, H5 subjected to the offset processing, the correction amounts V1, H1, M2, M3 (V3,
H3) Calculate the angular positions of M4, V5, H5 and M3.

Then, a rough correction operation is performed based on the calculated correction amount.

Processing for finish correction: Measure the unbalance on the main correction surfaces 1, 5 for the asymmetric crankshaft after rough correction, and repeat the above based on the measured component components V1, H1, V5, H5. By the same processing as described above, the correction amounts in the main correction planes 1, 5 and the auxiliary correction planes 2, 3, 4 are calculated.

It should be noted that the auxiliary correction surface 3
It is necessary to calculate so that the correction plane M3 in (3) becomes M3 = 0. This is because, on the auxiliary correction surface 3, the angular position of the correction amount M3 at the time of the rough correction and at the time of the finish correction may be close to each other. In such a case, there is a risk that the interference of the drill holes may occur.

However, the shape of the counterweight is not the shape as in this embodiment or the decomposition angle is smaller than 60 degrees, and the component force of H and V is set on the correction surface 3 so that the drilled hole has a smaller size. If there is no restriction that interference will occur, it is not necessary to perform the offset process of reducing the fixed amount ΔU.

After the calculation, the finishing correction operation may be performed based on the finishing correction amount.

<Effects of the Invention> Since the present invention is configured as described above, imbalance correction of an asymmetric crankshaft can be performed efficiently and in a short time.

In addition, it is possible to perform unbalance correction that minimizes the amount of unbalance correction of the asymmetric crankshaft.

[Brief description of the drawings]

FIG. 1 is a reference diagram for explaining a case in which imbalance correction of an asymmetric crankshaft of a five-cylinder engine is performed using one embodiment of the present invention. FIGS. 2 and 3 show an embodiment of the present invention.
FIG. 5 is a diagram illustrating a range in which the unbalance of the main correction surface 1 can be corrected when the unbalance correction of the asymmetric crankshaft of the cylinder engine is performed. FIG. 4 is a diagram showing a range in which the unbalance of the main correction surface 5 can be corrected when the unbalance correction of the asymmetric crankshaft of the five-cylinder engine is performed according to the embodiment of the present invention. FIG. 5 is a block diagram of a circuit configuration example of the unbalance correcting apparatus according to one embodiment of the present invention. FIG. 6 is a block diagram of a circuit configuration example of a conventional imbalance correcting device. In the figure, 1,5 …… Main correction plane, 2,3,4 …… Auxiliary correction plane,
11… Calculation circuit, 12… Calculation circuit, 13… Vibration detector,
14 indicates a reference phase detector.

Claims (3)

(57) [Claims] 1. An unbalance correcting method for an asymmetric crankshaft, wherein the positions of a plurality of counterweights provided on a crankshaft are not located in a plane-symmetric position with respect to a central longitudinal section in a counterweight arrangement direction, An arbitrary counter weight is determined as a main correction surface, another counter weight is determined as an auxiliary correction surface, an unbalance in the main correction surface is measured, and the measured unbalance is stored in a first storage means. A determination is made as to whether all of the unbalances stored in the storage means can be corrected on the main correction surface, and if there is an uncorrectable unbalanced component, cancel the uncorrectable unbalanced component. Calculation correction data for correcting the auxiliary correction surface is obtained and stored in the second storage means. As a result of correcting the auxiliary correction surface based on the calculation correction data, the first storage means When the stored unbalance of the main correction surface is affected, a new unbalance in which the influence is vector-combined with the original unbalance of the main correction surface is regarded as the unbalance of the main correction surface in the first storage means. It is determined whether all the unbalances updated and stored in the first storage means can be corrected on the main correction surface, and the unbalance updated and stored in the first storage means cannot be corrected. Until the balance component is not included, the above processes are repeated. The unbalance updated and stored in the first storage unit and the correction data cumulatively stored in the second storage unit are obtained by repeating the above processes. An unbalance correction method comprising performing an unbalance correction on the basis of the information. 2. The method according to claim 1, wherein a plurality of counter weights different from the counter weights determined on the main correction surface are determined on the auxiliary correction surface, and when the above processing is performed, a plurality of auxiliary weights are determined. For each of the correction planes, calculate the calculation correction data to be corrected to cancel the uncorrectable unbalance component of the main correction plane, and select the appropriate auxiliary correction plane for the calculation correction data, An unbalance correction method, wherein the calculated correction data of the selected auxiliary correction surface is stored in a second storage means. 3. An apparatus for correcting unbalance for an asymmetric crankshaft in which the positions of a plurality of counterweights provided on a crankshaft are not in a plane-symmetric position with respect to a central longitudinal section in the counterweight arrangement direction. Means for setting an arbitrary counter weight as the main correction plane and setting another counter weight as the auxiliary correction plane; first storage means for storing the measured unbalance on the main correction plane; Second storage means for storing correction data calculated on the correction surface; and determining whether all of the measured unbalances stored in the first storage means can be corrected on the main correction surface. If there is a possible unbalanced component, the second storage device obtains calculation correction data for correcting the auxiliary correction surface in order to cancel the uncorrectable unbalance component. A processing means for storing the correction data on the auxiliary correction surface based on the calculated correction data, if the unbalance of the main correction surface stored in the first storage means is affected, Processing means for updating and storing, in the first storage means, a new unbalance obtained by vector-combining the original unbalance of the main correction plane as the unbalance of the main correction plane; and processing of the unbalance updated and stored in the first storage means. A processing repetition means for judging whether or not all can be corrected on the main correction surface, and repeating the above processing until the unbalance updated and stored in the first storage means does not include an uncorrectable unbalance component. And an unbalance correcting means for performing an unbalance correction based on the unbalance updated and stored in the first storage means and the correction data cumulatively stored in the second storage means, which are obtained by repeating the above processing. , Unbalance correction device which comprises a.