JP6915394B2 - Work shape correction method - Google Patents

Description

The present invention relates to a method for correcting the shape of a work.

A technique is known in which the work is partially pressed so that the dimensions of the work are within an allowable range to correct the shape of the work (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-20183

In the case of the above-mentioned correction, it is conceivable to position the work on the positioning portion provided on the support base and then clamp the work to correct the shape of the work. In this case, if there is a gap between the positioning portion and the work, the position of the work may shift by the amount of the gap due to pressing against the work during straightening. This may reduce the dimensional accuracy of the workpiece after straightening.

Therefore, an object of the present invention is to provide a method for correcting the shape of a work in which a decrease in dimensional accuracy after correction is suppressed.

The above purpose is to press the work set on the support base and not clamped in a predetermined direction until the positioning portion provided on the support base regulates the displacement of the work, thereby preliminarily positioning the work. A step of shifting the work, a step of clamping the work whose position has been shifted in advance, a step of deforming and correcting the clamped work by pressing it with a pressing member in a predetermined direction, and the pressing. The step of measuring the dimension of the corrected portion of the work by the distance sensor while the member is retracted from the work, and when the measured dimension is out of the permissible range, the clamped work is re-clamped. This can be achieved by a method of shape correction of a work including a step of deforming and correcting by pressing with the pressing member in a predetermined direction.

According to the present invention, it is possible to provide a method for correcting the shape of a work in which a decrease in dimensional accuracy after correction is suppressed.

FIG. 1A is a schematic configuration diagram of a straightening device that corrects the shape of a work, and FIG. 1B is a block diagram of the straightening device. FIG. 2A is a view of the work set on the support base as viewed from above, and FIGS. 2B and 2C are enlarged views of the positioning hole and the positioning pin. FIG. 3A is a graph plotting the output value of the distance sensor after the correction is completed and the actual dimensions, and FIG. 3B is the output value of the distance sensor after the correction is completed when the pressing is executed before the correction. It is a graph in which and the actual dimensions are plotted. FIG. 4 is a flowchart showing an example of correction control.

FIG. 1A is a schematic configuration diagram of a straightening device 1 that corrects the shape of the work 10, and FIG. 1B is a block diagram of the straightening device 1. The straightening device 1 includes a support base 20, straightening mechanisms 30a to 30e, an elevating device 40, and distance sensors Sa to Se.

The work 10 has a flat plate portion 11 formed in a substantially flat plate shape, a step portion 12 at a position higher than the flat plate portion 11, and a vertical portion 13 extending substantially vertically upward from the step portion 12. Two positioning holes 14 are formed in the flat plate portion 11. The work 10 is an aluminum die-cast cast part used for, for example, a vehicle, but the work 10 is not limited to this if it is made of metal, and the shape of the work 10 is not limited to the above.

Support portions 22a to 22c are fixed to the upper surface of the support base 20, and the work 10 is supported by the support portions 22a to 22c. The heights of the support portions 22a to 22c are different so as to correspond to the shape of the work 10. Specifically, the support portion 22a supports the step portion 12, the support portions 22b and 22c support the flat plate portion 11, and the support portion 22a is formed higher than the support portions 22b and 22c, respectively. Further, on the upper surface of the work 10, two positioning pins 24 longer than each of the support portions 22a to 22c are formed. FIG. 1A shows a state in which the work 10 is positioned and set on the support base 20 by inserting the two positioning pins 24 into the positioning holes of the work 10. The positioning pin 24 is provided on the upper surface of the support base 20.

The elevating device 40 is a device that elevates and lowers the clampers 42a to 42c by a servo mechanism or a fluid pressure cylinder. The clampers 42a to 42c are adjusted so as to be located vertically above the support portions 22a to 22c, respectively. When the elevating device 40 lowers the clampers 42a to 42c, the clampers 42a to 42c press the work 10 between the support portions 22a to 22c, respectively. As a result, the work 10 is clamped.

The distance sensors Sa to Se measure the distance to the correction position of the work 10 described later. The straightening mechanisms 30a to 30e will be described in detail later, but by pressing the work 10, the work 10 is plastically deformed to correct the shape of the work 10. In FIG. 1A, only the correction mechanisms 30b and 30e are shown, and the correction mechanisms 30a, 30c, and 30d are not shown. The straightening mechanism 30b straightens a predetermined portion of the vertical portion 13. The straightening mechanism 30e straightens a predetermined portion of the flat plate portion 11.

The controller 100 is electrically connected to the straightening mechanisms 30a to 30e, the elevating device 40, and the distance sensors Sa to Se, and controls the operation of the straightening device 1 as a whole. The controller 100 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a storage device, and the like. The controller 100 controls the correction mechanisms 30a to 30e based on the respective output values of the distance sensors Sa to Se.

FIG. 2A is a view of the work 10 set on the support base 20 as viewed from above. The correction mechanisms 30a to 30e and the distance sensors Sa to Se are arranged so as to face each predetermined position of the work 10. The straightening mechanisms 30a and 30b straighten a predetermined portion of the vertical portion 13. The correction mechanism 30c corrects a predetermined portion of the step portion 12. The straightening mechanisms 30d and 30e straighten a predetermined portion of the flat plate portion 11. In FIG. 2A, the correction mechanisms 30a to 30e and the distance sensors Sa to Se are shown in a plane for easy understanding. Therefore, for example, as shown in FIG. 1A, the E-axis of the correction mechanism 30e is along the vertical direction, but in FIG. 2A, it is developed and described in the plane direction for easy understanding.

The straightening mechanisms 30a to 30e have pressing members 32a to 32e and actuators 34a to 34e, respectively. The pressing members 32a to 32e are moved back and forth with respect to the work 10 in the A-axis to E-axis directions by the actuators 34a to 34e, respectively. Further, the pressing members 32a to 32e plastically deform the work 10 by pressing each part of the work 10. Specifically, the pressing members 32a and 32b press a predetermined portion of the vertical portion 13. The pressing member 32c presses a predetermined portion of the step portion 12. The pressing members 32d and 32e press a predetermined portion of the flat plate portion 11. The actuators 34a to 34e drive the pressing members 32a to 32e so as to be able to move forward and backward in the A-axis to E-axis directions, respectively. Actuators 34a to 34e are, for example, electric actuators driven by servomotors and cylinders driven by atmospheric pressure or flood control. The A-axis to E-axis directions are set so as to intersect rather than be parallel to each other, but the present invention is not limited to this. The pressing member 32b and the actuator 34b are formed larger than the other pressing members and the actuator, respectively, but are not limited thereto.

The distance sensors Sa to Se measure the dimensions of the straightened portion by measuring the distance of the straightened portion of the work 10 pressed by the pressing members 32a to 32e, respectively. Specifically, the distance sensors Sa and Sb measure the distance of the corrected portion of the vertical portion 13 pressed by the pressing members 32a and 32b, respectively. The distance sensor Sc measures the corrected portion of the step portion 12 pressed by the pressing member 32c. The distance sensors Sd and Se measure the distance of the straightened portion of the flat plate portion 11 pressed by the pressing members 32d and 32e, respectively. The distance sensors Sa to Se are, for example, laser displacement meters, but may be contact type displacement sensors. The distance sensor Sb is provided with three, the distance sensor Se is provided with two, and the other distance sensors Sa, Sc, and Sd are provided with one each, but the present invention is not limited thereto.

The straightening method will be described in detail later, but while checking the dimensions of the straightened portion of the work 10 with a distance sensor, the straightened portion is repeatedly pressed until the dimensions at the straightened portion are within a predetermined allowable range. Is transformed. When the dimensions of the work 10 at each straightening portion are included within the permissible range corresponding to each, the straightening of the shape of the work 10 is completed.

Here, as shown in FIG. 2A, two positioning holes 14 are formed in the work 10, and two positioning pins 24 are inserted into the two positioning holes 14 and set on the support base 20. If the work 10 is clamped by the clampers 42a to 42c in the state of being set in this way and the shape of the work 10 described above is corrected, the following problems may occur during the correction.

2B and 2C are enlarged views of the positioning hole 14 and the positioning pin 24. As shown in FIG. 2B, the inner diameter of the positioning hole 14 is formed to be larger than the outer diameter of the positioning pin 24 in consideration of the ease of inserting the positioning pin 24 into the positioning hole 14. That is, a gap is provided between the inner diameter of the positioning hole 14 and the outer diameter of the positioning pin 24. Therefore, for example, even when the work 10 is clamped, the sliding position of the work 10 is displaced when a pressing force for correcting the shape of the work 10 is applied to the work 10 from any of the pressing members 32a to 32e. There is a possibility of deviation. For example, even if the work is clamped in the state of FIG. 2B, the position of the work 10 may shift due to the pressing force on the work 10 during straightening, resulting in the state of FIG. 2C.

Therefore, it is determined whether the dimension of each straightening portion measured by each of the distance sensors Sa to Se is the dimension after the actual plastic deformation or the dimension after the misalignment occurs as described above. Can not. Therefore, even if the dimensions of the work 10 at each straightening portion are included within the permissible range corresponding to each, the above-mentioned misalignment actually occurs, and the work 10 after the straightening is completed. Dimensional accuracy may decrease. FIG. 3A is a graph plotting the output value of the distance sensor and the actual dimensions after the correction is completed. The horizontal axis shows the output value of the distance sensor that measures the dimensions of the straightened part, and the vertical axis shows the actual dimensions of the straightened part. As shown in FIG. 3A, the degree of correlation between the output value of the distance sensor and the actual dimension is low, and there is a possibility that a misalignment has occurred. Therefore, even if the shape of the work 10 is corrected while checking the dimensions of the work 10 based on the distance sensors Sa to Se as described above, there is a possibility that the dimensional accuracy of the work 10 after the correction is completed is lowered. There is.

In the straightening control in this embodiment, before the shape of the work 10 is straightened, the position of the work 10 is preliminarily shifted in the state where the work 10 is unclamped until further misalignment is regulated by the positioning pin 24. The push-in is executed. That is, by intentionally causing the misalignment of the work 10 in advance before the straightening of the work 10, the occurrence of the misalignment of the work 10 during the straightening is suppressed. FIG. 3B is a graph in which the output value of the distance sensor after the correction is completed and the actual dimensions are plotted when the pressing is executed before the correction. As shown in FIG. 3B, the output value of the distance sensor and the actual dimensions have a substantially proportional relationship, and it can be seen that the degree of correlation is greater than in the case of FIG. 3A. Therefore, the deterioration of the dimensional accuracy of the work 10 after the correction is completed is suppressed.

Next, the correction control executed by the controller 100 will be specifically described. FIG. 4 is a flowchart showing an example of correction control. When the straightening device 1 is started with the positioning pin 24 inserted into the positioning hole 14 of the work 10 and set on the support portions 22a to 22c, the work 10 is supported based on the output values of the distance sensors Sa to Se. It is determined whether or not the table 20 is set (step S1). Specifically, when the output values of the distance sensors Sa to Se belong to the predetermined ranges set for each of the distance sensors Sa to Se, an affirmative judgment is made, and any of the output values falls within the corresponding predetermined range. If it does not belong, the work 10 is determined to be unset or not set normally (step S3), and this control ends.

In the case of an affirmative determination in step S1, the clampers 42a to 42c are lowered by the elevating device 40 to press the work 10 toward the support portions 22a to 22c with a predetermined load, and the work 10 is clamped (step S5). .. Next, it is determined again whether or not the shape of the work 10 can be corrected based on the output values of the distance sensors Sa to Se (step S7). Specifically, when the output values of the distance sensors Sa to Se belong to the predetermined ranges set for each of the distance sensors Sa to Se, an affirmative judgment is made, and any of the output values falls within the corresponding predetermined range. If it does not belong, a negative judgment is made. In the case of a negative determination in step S7, an abnormality determination is made as the work 10 has an uncorrectable shape (step S8), the elevating device 40 is raised, the clampers 42a to 42c are retracted from the work 10, and the work 10 is retracted. Is unclamped (step S9), and this control ends.

In the case of an affirmative determination in step S7, the lifting device 40 separates the clampers 42a to 42c slightly from the work 10, for example, about 0.5 mm, and the work 10 is unclamped (step S11a). Next, the pressing member 32a of the straightening mechanism 30a pushes the vertical portion 13 of the work 10 in the A-axis direction (step S13a). As a result, the work 10 is displaced in the A-axis direction until the positional deviation is regulated by the positioning pin 24. Therefore, the misalignment of the work 10 during the subsequent correction in the A-axis direction is suppressed. The pressing force applied to the work 10 by the above pushing is set so that the position of the work 10 is displaced until the positioning pin 24 regulates the displacement in the unclamped state, but the work 10 is not deformed.

Next, the work 10 is clamped again (step S15a), and the vertical portion 13 is straightened in the A-axis direction (step S17a). Specifically, it is executed as follows. First, the distance to the straightened portion of the vertical portion 13 of the work 10 pressed by the pressing member 32a is measured based on the distance sensor Sa. Next, the straightened portion of the vertical portion 13 of the work 10 is pressed by the pressing member 32a with a straightening pressing force. The pressing force for straightening is a force larger than the pressing force for pressing described above, and is set to a size that allows the work 10 to be plastically deformed. Next, the pressing member 32a is retracted from the vertical portion 13 of the work 10, and the dimension of the straightened portion of the vertical portion 13 of the work 10 in the A-axis direction is measured again based on the distance sensor Sa. The reason why the dimension of the straightened portion in the A-axis direction is measured not in the state where the work 10 is pressed by the pressing member 32a but in the state where the work 10 is retracted from the work 10 is that the spring after the pressing force on the work 10 is released. This is to measure the size of the corrected part that reflects the amount of return due to the back.

Next, a pass / fail determination of the dimensions of the corrected portion in the A-axis direction is made (step S19a). Specifically, an affirmative judgment is made when the dimension of the straightened portion 13 of the work 10 in the A-axis direction is within a predetermined allowable range, and a negative judgment is made when the dimension is out of the allowable range. .. If a negative determination is made in step S19a, the process of step S17a is executed again. That is, the correction in the A-axis direction is repeatedly executed until the dimension of the correction portion in the A-axis direction is passed.

In the case of an affirmative determination in step S19a, the same processing as described above is executed in the order of the B axis to the E axis. Specifically, the work 10 is unclamped (step S11b), the work 10 is pushed in the B-axis direction by the pressing member 32b (step S13b), the work 10 is re-clamped (step S15b), and the work 10 is re-clamped in the B-axis direction. The correction of the vertical portion 13 of the work 10 is executed (step S17b), the pass / fail determination of the dimensions of the vertical portion 13 of the work 10 in the B-axis direction after the correction is executed (step S19b), and the negative determination is made in step S19b. In the case of, step S17b is executed again.

In the case of an affirmative determination in step S19b, the work 10 is similarly unclamped (step S11c), the work 10 is pushed in the C-axis direction by the pressing member 32c (step S13c), and the work 10 is re-clamped (step S13c). S15c), the step portion 12 of the work 10 in the C-axis direction is straightened (step S17c), and the pass / fail determination of the dimension of the step portion 12 of the work 10 in the C-axis direction after the straightening is executed (step S19c). ), If a negative determination is made in step S19c, the process of step S17c is executed again.

If a positive judgment is made in step S19c, the work 10 is unclamped (step S11d), the work 10 is pushed in the D-axis direction by the pressing member 32d (step S13d), and the work 10 is re-clamped (step S15d). The flat plate portion 11 of the work 10 is straightened in the D-axis direction (step S17d), and the pass / fail determination of the dimensions of the flat plate portion 11 of the work 10 in the D-axis direction after the straightening is executed (step S19d). If a negative determination is made in S19d, the process of step S17d is executed again.

If a positive judgment is made in step S19d, the work 10 is unclamped (step S11e), the work 10 is pushed in the E-axis direction by the pressing member 32e (step S13e), and the work 10 is re-clamped (step S15e). The flat plate portion 11 of the work 10 is straightened in the E-axis direction (step S17e), and the pass / fail determination of the dimensions of the flat plate portion 11 of the work 10 in the E-axis direction after the straightening is executed (step S19e). If a negative determination is made in S19e, the process of step S17e is executed again.

In the case of affirmative determination in step S19e, the pass / fail determination of the dimensions of the work 10 in all directions of the A-axis to E-axis is made based on the distance sensors Sa to Se (step S21), and in the case of negative determination, the pass / fail determination is made. An abnormality determination is made on the assumption that any of the dimensions is not within the permissible range (step S23), and the dimension is unclamped (step S25). If the affirmative judgment is made in step S21, the shape of the work 10 is unclamped as if it was normally corrected (step S25). With the above correction control, a decrease in dimensional accuracy of the work 10 after correction in all directions from the A axis to the E axis is suppressed.

In the steps S13a, S13b, S13c, S13d, and S13e, the work 10 set on the support base 20 and not clamped is regulated by the positioning pin 24 provided on the support base 20, respectively. This is an example of a step of shifting the position of the work 10 in advance by pressing in the A-axis to E-axis directions until the work 10. The steps S15a, S15b, S15c, S15d, and S15e are examples of steps of clamping the work 10 that has been displaced in advance. The steps S17a, S17b, S17c, S17d, and S17e are examples of steps of deforming the clamped work 10 by pressing it in the A-axis to E-axis directions, respectively.

As an example of the positioning unit, the positioning pin 24 inserted into the positioning hole 14 of the work 10 has been described, but the present invention is not limited to this. For example, the positioning portion may be a protrusion-shaped or wall-shaped portion provided on the set table, and may position the work by abutting on a part of the outer peripheral surface of the work. In this case as well, the unclamped work is pressed in a predetermined direction until the positioning portion regulates the misalignment to shift the position of the work in advance, and then the work is clamped and the work is moved in the same predetermined direction. It may be deformed by pressing.

Although the examples of the present invention have been described in detail above, the present invention is not limited to such specific examples, and various modifications and modifications are made within the scope of the gist of the present invention described in the claims. It can be changed.

1 Orthodontic appliance 10 Work 14 Positioning hole 20 Support base 24 Positioning pin (positioning part)
30a to 30e Correction mechanism 32a to 32e Pressing member 34a to 34e Actuator 40 Lifting device 42a to 42c Clamper 100 Controller Sa to Se Distance sensor

Claims (1)

The position of the work is shifted in advance by pressing the work set on the support base and not clamped in a predetermined direction until the positioning portion provided on the support base regulates the displacement of the work. Process and
The process of clamping the work that has been displaced in advance, and
A step of deforming and correcting the clamped work by pressing it with a pressing member in the predetermined direction.
A step of measuring the dimension of a corrected portion of the work by a distance sensor with the pressing member retracted from the work, and a step of measuring the dimensions of the corrected portion of the work.
A method for correcting the shape of a work , comprising a step of deforming and straightening the clamped work by pressing the clamped work in a predetermined direction with the pressing member when the measured dimensions are out of the permissible range. ..

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