JP2001105028A - Method for deciding position for straightening bend of bar and amount to be straightened - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for deciding a position for straightening the bend of a bar and an amount to be straightened by which high accuracy of straightening is attained with a small number of times of straightening without depending on the manual operation of a skilled technician and which is easily automated. SOLUTION: Deflection in plural places in the longitudinal direction of a work is measured at prescribed phase intervals and, from the amount of deflection, phase data and measuring coordinate at each measuring point, the amount R of deflection and partial bend angle θat each measuring point in a prescribed phase cross section of the work are calculated. By reproducing measured deflection data on calculation by accumulating the amount R of deflection and partial bend angle θ by each phase, the predictive calculation of simulation straightening using those reproduced data and the deflection of the whole work after the simulation straightening is predicted. The optimum straightening position, straightening phase and straightening amount are decided so that the predicted value of the deflection is not larger than the standard value (target value). By executing a series of these calculations about all the combinations of each straightening phase, straightening position and straightening amount, the optimum straightening position and straightening amount are determined at the minimum number of times of straightening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a straightening position and a straightening amount of a bent bar having a bent, and simulates a corrected result of the bent by using a previously measured bending data, and simulates the calculated result. The optimum correction position, correction phase, and correction amount are determined so that the value of the workpiece shake is equal to or less than the standard value.

[0002] The term "bar" as used herein includes a threaded shaft having a thread groove.

[0003]

2. Description of the Related Art The bending of a long bar is corrected by applying a load (correcting load) in a direction opposite to the bending direction to a bent portion of the bar. In this case, it is necessary to determine the position where the correction load is applied, the amount to be corrected, and the like. Conventionally, straightening is performed such that the bending becomes zero at the position where the deflection becomes maximum when rotating while supporting both ends of the bar to be corrected or at the maximum position of the bending measured at a certain span in the longitudinal direction of the bar. I am correcting for the amount.

[0004]

However, when a certain portion is corrected with a bar having a plurality of bends, the correction affects deflection at a bend in another portion. Therefore, as described above, it is necessary to correct not only the bend at the position where the deflection and the bend are maximum, but also the other bends affected by the bend, and the correction takes a long time. There is a point.

In the case of a bar having a complicated curve in which the phase of the curve differs depending on the position in the longitudinal direction, it is impossible to correct the deflection with high precision, and it is impossible to realize a stable correction. However, there is a problem that automation is difficult, and manual correction by a skilled technician must be performed. Therefore, the present invention has been made by focusing on such unresolved problems of the prior art, and without manual work of a skilled technician, it is easy to automate to obtain high correction accuracy with a small number of corrections. It is an object of the present invention to provide a method for determining a bending correction position and a correction amount of a bar.

[0006]

In order to achieve the above object, a bar (work) according to the present invention is provided with a straightening position,
The correction amount is determined by measuring deflections at a plurality of positions in a longitudinal direction of a bent bar (work) at predetermined phase intervals.

[0007] From the obtained runout amount, phase data, and measurement coordinates at each measurement location, a runout amount R and a partial bending angle θ at each measurement location in a predetermined work phase cross section are calculated. By accumulating the shake amount R and the partial bend angle θ for each measurement point calculated for each phase, the shake data of the work measured by is reproduced. Prediction calculation of the simulation correction result in each phase is performed using the obtained reproduction data of the "partial bending amount", and the result is accumulated again for each phase to predict the runout of the entire work after the simulation correction.

An optimum correction position, a correction phase, and a correction amount are determined so that the value of the workpiece runout due to the simulated correction is equal to or less than a standard value. By performing a calculation for all combinations of each correction phase, correction position, and correction amount with this series of calculation methods, it is possible to obtain the correction position and correction amount for correcting the shake target with the minimum number of corrections. Will be possible.

In addition, even when there are many measurement positions in the longitudinal direction, it takes time to calculate all combinations, and it is not practical due to the performance of the arithmetic unit, correction is performed in a sufficiently short time and with high accuracy in practical use. It becomes possible. According to the present invention, when a bent bar is corrected by a specific correction amount at a specific position and a specific phase, the influence on the runout of the entire bar is calculated, so that another bar can be obtained before correction. Predict the effect of correction on longitudinal position and phase. By performing calculations for all combinations of the position in the longitudinal direction of the bend, the phase, and the correction amount, it is possible to obtain the optimum correction position and correction amount that can satisfy the deflection standard and can be corrected with the minimum number of corrections. Moreover, it is possible to perform the correction with high accuracy regardless of the bending state before the correction.

[0010] Thus, it has become possible to realize automation of straightening for correcting the bending of a long bar, which has been conventionally performed by a skilled worker, with high precision.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a flowchart showing an outline of a bending correction operation according to the method of determining a bending correction position and a correction amount of a bar according to the present invention. First, deflection of a bent bar (work) is measured at measurement positions set at a plurality of positions in the longitudinal direction of the work (step 1).

The measured run-out is compared with the correction standard, and it is determined whether the run-out is smaller than the correction standard. On the other hand, if the shake is larger than the correction standard, the process proceeds to step 3 (step 2). A correction amount at which the shake is minimized at the shake maximum position and the phase is predicted (step 3).

The predicted shake is compared with the shake target, and it is determined whether or not the predicted shake <the shake target (step 4). If the predicted shake is smaller than the shake target, the flow jumps to step 6 to execute the correction. On the other hand, if the predicted shake is larger than the shake target, the partial bend = 0 at the partial bend maximum position and phase.
(Step 5).

The correction is executed according to the correction amount (step 6). Returning to step 1, the deflection of the work after the correction is measured, and steps 2 and subsequent steps are repeated according to the result.
Next, details of the measurement and calculation in each of the above steps will be described. (1) A step of measuring the run-out of the work and obtaining the run-out amount and phase.

In order to improve the bending correction accuracy, it is necessary to accurately grasp the deflection of the work. Therefore, in the present embodiment, as shown in FIG. 2, while rotating the shaft while supporting both ends of the work W, the run-out at measurement positions (P ₁ , P ₂ , P _3, etc.) set at a plurality of positions in the longitudinal direction. Is measured at predetermined phase intervals (for example, at 1-degree intervals from 0 to 360 degrees) using a measuring means G such as an electric micrometer. In this case, the approximated curve is obtained by approximating the measured data of the shake and the phase with a trigonometric function and the like, and the amount of the shake and the phase of the approximate curve is calculated. The accuracy can be improved by removing it.

For example, FIG. 3 shows an example of an approximation curve obtained by approximating a shake measured at a predetermined phase interval (measurement point) at a measurement position P ₁ by a trigonometric function while rotating the work W by one rotation. . Each measurement point (phase) of this approximation curve
The shake amount Rr for each calculation is used for the next calculation. (2) a step of calculating a run-out and a partial bend at each phase section of the work from the above-mentioned run-out amount and phase data;

FIG. 4 schematically shows the state of deflection and partial bending in a phase section S (Θ) obtained by cutting a bent workpiece W in a longitudinal direction at a certain phase Θ (Θ = 90 degrees in the figure). FIG. 5 shows the phase cross section S
Runout R ₁ (Θ) and partial bending θ in (に お け る)
FIG. 3 is a diagram for explaining a method of calculating ₁ (Θ) based on data of a shake amount Rr and a phase of the approximate curve.

That is, n measurement positions P ₁ , P ₂ , P _3, ... P _n are set in the longitudinal direction of the work, and the run-out is measured by setting the entire circumference of 0 to 360 degrees as, for example, a phase angle of 1 degree. Of the obtained measurement values, the shake R at each measurement position _Pn in a phase cross section S (Θ) of a certain phase Θ (eg, Θ = 90 degrees)
_n (Θ) and partial bending θ _n (Θ) are calculated as follows using the shake amount Rr (Θ) and shake phase of the approximate curve.

The measured values of the shake and phase are analyzed and converted into shake data and partial bending data in the work phase cross section S (断面). For example, the deflection R ₁ (Θ) at the measurement position P ₁ is given by the following equation (1).
by. R ₁ (Θ) = (shake amount _{Rr 1 × 1/2) ×} Cos ( phase deviation -Θ) ...... (1) each measurement position P _2, P ₃ ... shake in P _n R ₂ (Θ),
R ₃ (Θ),..., R _n (Θ) are similarly converted.

The partial bend θ ₁ (Θ) at the measurement position P ₁ is given by the following equation (2). θ ₁ (Θ) = tan ^-1 ｛(R ₀ (Θ) -R ₁ (Θ)) / X ₁ ｝ + tan ^-1 ｛(R ₂ (Θ) -R ₁ (Θ)) / X ₂ … ... (2) each measuring position P _2, P ₃ ... partial curve amount theta ₂ at P _n
(Θ), θ ₃ (Θ),... Θ _n (Θ) are similarly converted.

However, R ₀ (Θ) = 0, R _{n + 1} (Θ) = 0 FIG. 6 shows the state of the deflection and partial bending of the phase section Θ obtained in this way, and the measurement positions P ₁ , P FIG. 3 is a three-dimensional image diagram schematically showing a shake / phase approximation curve measured at ₂ and P ₃ . (3) The data of the partial bend is accumulated to create the data of the deflection.

The phase Θ obtained for each of the measurement positions P _{1 to} P _n
Partial bending θ ₁ (Θ), θ ₂ (Θ), θ ₃ (Θ),
... Θ _n (Θ) is accumulated. Similarly, it accumulates each phase (e.g. one degree intervals over 0-360 degrees) another partial curve amount at each measurement position P ₁ to P _n. As a result, data indicating the deflection of the work W can be reproduced. That is, first, as shown in FIG. 7, θ ₁ (Θ), θ ₂ (Θ),
From θ ₃ (Θ) and the values of the intervals (longitudinal coordinates) X ₁ , X ₂ , X ₃ , and X ₄ between the measurement positions P ₁ , P ₂ , P ₃ , and P ₄ ,
Back calculated displacement R ' ₁ (Θ), R' ₂ (Θ) , R '
₃ (Θ) , R ′ ₄ (Θ).

Next, as shown in FIG.
So that the last value of the displacement is 0, that is, R '
_FourBy tilting the cumulative deflection line so that (Θ) = 0, a new
Swing R " ₁(Θ), R "_Two(Θ), R "_Three(Θ)
Confuse. Thus, the partial bending data at a certain phase Θ
TA θ_nWhen (を) is accumulated in the longitudinal direction,
Run-out R_n(Θ) can be reproduced by calculation
Wear. (4) The data of the partial bend reproduced by the calculation
Data to be corrected, and the changed data
By re-accumulating in the hand direction, the
Predict the run-out of the work. For example, as shown in FIG.
The calculated partial bend data is accumulated and reproduced
Of the bending line L in the work longitudinal direction at the phase た
Minute bending position P₁Calculate run-out after adding correction load F
By re-accumulating the data,
A post-correction curved line L 'as shown in FIG. Figure
9 (b) before correction, and FIG. 10 (b) after correction prediction.
It is a figure of the three-dimensional image of each curve.

The correction equation for obtaining the corrected curved line after the correction is given by the following equation (3) at the phase Θ at the correction location. New partial bend (Θ) = old partial bend (Θ) −partial bend correction amount × Cos (Θ−correction phase) (3) Thereby, the partial bend amount in each phase is corrected, and the results are accumulated again. Then, the run-out of the entire work when the partial bending is corrected can be predicted by calculation.

That is, when the bending correction is actually performed at a specific position, the partial bending value of each phase at the correction position changes under the influence of the correction, so that the influence must be corrected. However, in the present invention, using the data of the partial bend reproduced by calculation, the amount of shake and the shake phase at each measurement point after correction are predicted, and the correction amount that minimizes the shake at the maximum position and phase of the shake is determined. The optimal correction point, so that the predicted value is less than the runout target value (standard value),
The correction position and the correction amount (partial bending amount) are obtained by calculation, and the actual correction work is performed based on the calculation result. Therefore, high correction accuracy can be obtained with a small number of corrections.

[0026]

As described above, according to the present invention,
Highly efficient and high-precision bending straightening is performed because the determination of the bending straightening position and straightening amount of the bar is simulated and calculated from the measured run-out to predict and perform the actual straightening work based on the obtained optimum value. Can be automated, and it is possible to greatly contribute to the elimination of the manual work of the skilled person.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an outline of a bending correction operation according to a method for determining a bending correction position and a correction amount of a bar according to the present invention.

FIG. 2 is a perspective view illustrating a method of measuring the run-out of a workpiece.

[3] The deflection was measured at predetermined phase intervals (measurement points) in the measuring position P _1, an example of the approximate curve obtained by approximating a triangle function.

FIG. 4 is a phase cross section S obtained by cutting the work W in the longitudinal direction.
It is the two-dimensional image figure which displayed typically the state of the deflection and partial bending in (II).

FIG. 5 is a diagram illustrating a method of calculating a shake R ₁ (Θ) and a partial bending amount θ ₁ (Θ) in a phase cross section S (Θ) based on data of a shake amount and a phase of the approximate curve.

FIG. 6 is a three-dimensional image diagram schematically showing the state of the deflection and partial bending of the phase cross section 及 び and the deflection ── phase approximation curve measured at each of the measurement positions P ₁ , P ₂ , and P ₃ .

FIG. 7 is a diagram illustrating a method of reproducing the actually measured deflection of the work W by calculation.

FIG. 8 is a diagram illustrating a method of reproducing the actually measured deflection of the work W by calculation.

9A is a two-dimensional image diagram showing a curved line L in the longitudinal direction of a work before correction reproduced by calculation, and FIG. 9B is a three-dimensional image diagram thereof.

10A is a two-dimensional image diagram showing a curved line L ′ in the longitudinal direction of a work after correction, which is predicted by calculation, and FIG. 10B is a three-dimensional image diagram thereof.

Claims (1)

[Claims] 1. A method for determining a bending correction position and a correction amount of a bar, which includes the following steps. The deflection at a plurality of locations in the longitudinal direction of the work is measured at predetermined phase intervals. From the obtained shake amount, phase data and measurement coordinates at each measurement point, a shake amount R and a partial bending angle θ at each measurement point in a predetermined work phase cross section are calculated. By accumulating the shake amount R and the partial bend angle θ for each measurement point calculated for each phase, the shake data of the work measured by is reproduced. Prediction calculation of the simulation correction result in each phase is performed using the obtained reproduction data of the "partial bending amount", and the result is accumulated again for each phase to predict the runout of the entire work after the simulation correction. The optimum correction position, correction phase, and correction amount are determined so that the value of the workpiece run-out due to the simulated correction is equal to or less than the standard value. According to this, the work is actually corrected.