JPH07185960A - Spline manufacturing target dimension control method - Google Patents

Abstract

PURPOSE:To decide manufacturing target dimensions in consideration of a combined error which is hard to grasp quantitatively. CONSTITUTION:An average value XAV for each items and standard deflection 6 are computed by respectively measuring O.B.D dimensions or B.B.D dimensions of a shaft spline and a hole spline, a tooth profile error which is a combined error, a lead error and a pitch error. The average value XAV and the standard deflection 6 are computed by finding an engagement error by way of extracting optional precision combination of the shaft spline and the hole spline from dispersion distribution of the eight items. A shift amount of an engagement error average value required to keep distribution of the engagement error in a range of an engagement error target value is found. The optimum manufacturing target dimensions of the O.B.D dimensions and the B.B.D dimensions are computed in accordance with this shift amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a manufacturing target size of a spline.

[0002]

2. Description of the Related Art In the process of manufacturing a spline, not only the dimensional accuracy of the shaft spline or the hole spline alone, but also the fitting error (so-called "spline Even those that are referred to as “ta”) must be managed. B. B. for micrometer and hole spline. B. The spline is checked using a D-micrometer, a standard shape gauge, and a standard shape stop gauge.

The above-mentioned O. B. D is Over Ba
Ill Abbreviation for Diameter B.
D is an abbreviation for Between Ball Diameter, and therefore O.D. B. The D dimension means the tooth thickness dimension measured by the overball (pin) method for the axial spline, and similarly, B. B. The D dimension means the tooth groove width dimension measured by the overball (pin) method for the hole spline.

[0004]

As described above, the O.D. B.
D micrometer and B.I. B. When the D micrometer is used, as shown in FIG. B. D dimension and B. B. Although it is possible to measure the D dimension, when using an in-line gauge or a dead-end gauge, the gauge itself is set based on the drawing values of the spline. It is only possible to determine whether or not it is within the allowable range.

Therefore, as shown in FIG. 8, for example, when the fitting error between the shaft spline and the hole spline actually exceeds the permissible range,
Based on the fitting error target value and the fitting error measured value, O.I. B. D dimension and B.I. B. In re-determining the manufacturing target size for the D size, O. B. D dimension and B.
B. Although it is necessary to grasp the total error in addition to the D dimension variation, the total error cannot be measured at all.

As a result, conventionally, in determining the final manufacturing target size, it is necessary to rely on experience and intuition, which not only imposes a heavy burden on the operator, but also tends to cause variations in individual differences. there were.

Here, the total error is a general term for a tooth profile error, a lead error and a pitch error that determine the accuracy of the spline, and the actual tooth thickness dimension (OBD dimension and BBD dimension). The effective dimension of the fitting error is the sum of the above and the total error.

The present invention has been made by paying attention to the problems as described above, and the optimum manufacturing target dimension concerning the tooth thickness dimension is taken into consideration after fully considering the total error which could not be quantitatively grasped in the past. It is to provide a method that allows the decision.

[0009]

As shown in FIG. 1, the present invention measures the accuracy of a single spline and statistically processes the measurement result by a computer. A method of determining O.D. for each of a number of manufactured axial and hole splines. B. D dimension or B.I.
B. Measuring the accuracy error of a plurality of items in addition to the D dimension; B. D dimension or B.I. B. A step of obtaining an average value and a standard deviation for each of the D dimension and the accuracy errors of a plurality of items; B. D dimension or B.I.
B. A step of extracting a combination of an axial spline and a hole spline of arbitrary precision from the distribution of the D dimension and the precision error of a plurality of items, and determining a fitting error for each of a large number of combinations of the axial spline and the hole spline; The process of obtaining the average value and standard deviation of the fitting error, and the fitting required to put the distribution of the fitting error in the range of this fitting error target value based on the target fitting error. A step of obtaining a shift amount of the average value of the errors, and O.V. B. Dimension D and B. B. And a step of calculating and outputting an optimum manufacturing target dimension for the D dimension.

[0010]

According to this method, based on the measurement results of a large number of samples of the axial spline and the hole spline, the O.D. B. D dimension or B.I. B. In addition to D dimension variation, the distribution of tooth profile error, lead error, and pitch error variation, which is a total error, is calculated by statistical processing, while random sample combinations, that is, fitting by a combination of shaft spline and hole spline. After calculating the error and performing statistical processing to calculate the distribution of the fitting error, the optimum O.D. when finally combined with the spline on the other side. B. D dimension or B.I.
B. Since the manufacturing target size for the D dimension is determined by estimation, the manufacturing target size sufficiently reflects the tooth profile error, the lead error, and the pitch error, which are the total errors.

Therefore, if the manufacturing target size is fed back to the processing machine side, even if the processing conditions change from moment to moment due to the external environment or the like, the fitting error will be within the fitting error target value. Can be modified.

[0012]

FIG. 2 is a system block diagram showing an embodiment of the present invention, in which the accuracy of the spline is measured by a gear measuring machine 1 or a three-dimensional measuring machine for each of a large number of machined shaft splines and hole splines. , The accuracy data of the spline obtained by the measurement is loaded into the workstation 2 and stored therein. If the measurement accuracy data reaches a predetermined number of samples, the workstation 2
Executes statistical processing as shown in FIG. 1 and executes O.D. of the axis spline and hole spline. B. D dimension or B.I. B. D
The optimum manufacturing target size relating to the size is calculated and output to the plotter 3 and the display 4 for display.

FIGS. 3, 4 and 5 show a more detailed processing procedure in the above system, in which the spline accuracy is measured by the gear measuring machine 1 of FIG. 2 for each of a large number of processed shaft splines and hole splines. The measurement is performed, and the measurement accuracy data is sequentially taken into the workstation 2 (steps S1 and S2).

In this case, the measurement items of the axial spline are O.S.
B. D dimension, tooth profile error, lead error, and pitch error. B. These are D dimension, tooth profile error, lead error, and pitch error.

Then, the above measurement is repeated until the number of collected sample data n reaches a preset value X (arbitrary number of 500 to 100) (step S
3, S4), and when n = X, the workstation 2 uses the statistical processing program to calculate the average value x _AV for each measurement item.
And the standard deviation σ are calculated (steps S5 and S6). That is, regarding the axial spline, the O.D. B. For each of the D dimension, the tooth profile error, the lead error, and the pitch error, the average value x _AV and the standard deviation σ are obtained. B. An average value x _AV and a standard deviation σ are obtained for each of the D dimension, the tooth profile error, the lead error, and the pitch error. Note that the above sample data is updated to the latest one at regular intervals.

Here, the average value x _AV and the standard deviation σ are obtained by the equations (1) and (2).

[0017]

[Equation 1]

Next, if each average value x _AV and standard deviation σ are obtained as described above, the workstation 2
Then, a normal random number (or a random number of Weibull distribution) is generated by the Box-Muller method based on a random number generation program (step S7), and the axis spline and the hole spline are calculated from the accuracy variation distribution of a total of 8 items for the axis spline and the hole spline described above. A combination of arbitrary precision of is extracted (step S8).

Then, based on the spline specification data (number of teeth, pressure angle, module, large and small diameter dimensions, etc.) input to the workstation 2 in advance, a fitting error simulation program is used to obtain the above-mentioned arbitrary accuracy. The fitting error at the time of spline fitting under the combination of is calculated (steps S9, S10, S11).

Here, the above normal random number generating program is represented as shown in FIG. 6, or as a fitting error simulation program, for example, Japanese Patent Application No. 5-161143.
Use those listed in No.

The number of samples n for calculating the fit error by the fit error simulation is 1000 to 100.
It is set to about 00, and a normal random number is generated each time until n = 1000 to 10000, and the fitting error under the combination of the above arbitrary precisions is repeatedly calculated (step S12).

Subsequently, the workstation 2 performs statistical processing on the basis of the fitting error data of the sample number n = 1000 to 10000 obtained as described above, and under the combination of the above-mentioned arbitrary precisions. An average value x _AV of fitting errors and a standard deviation σ are calculated (step S13).

Further, in the workstation 2, the distribution of the fitting error described above is kept within the range of the fitting error target value on the basis of the maximum allowable value and the minimum allowable value of the fitting error target value inputted in advance. The shift amount necessary for the calculation is calculated (steps S14 and S15).

That is, as shown in FIG. 7, step S
13, the shift amount Δx (deg) of the average value x _AV of the fitting error distribution necessary to keep the fitting error distribution calculated in S14 within the allowable width of the fitting error target value is calculated, and at the same time A value (μm) when the Δx (deg) is converted into a dimension in the tooth thickness direction is calculated at the same time.

Then, in the workstation 2, the O.S. of the shaft spline when the spline is fitted with the hole spline based on the above-mentioned amount of cyst. B. While calculating the D dimension, B. of the hole spline when the spline is fitted to the shaft spline in the same manner. B. Calculate D dimension (step S
16, S17). The above-mentioned target dimensions are the tooth thickness and the O.D. B. D dimension or groove width and B. B. It is a value determined from the relational expression with the D dimension.

After this, the above value is set to O. B. D dimension and B.I. B. It is output and displayed on the plotter 3 and the display 4 as the optimum target dimension for the D dimension.

As described above, according to this embodiment, the O.V. B. D
Dimensions and B. B. In addition to the variation of the D dimension, the variation of the total error such as the tooth profile error and the lead error is statistically processed individually, and the optimum manufacturing target dimension is calculated. B. D dimension and B. B. In addition to the D dimension, it is possible to determine the manufacturing target dimension in which the variation of the total error is taken into consideration.

[0028]

As described above, according to the present invention, the O.D. B. D dimension and B. B. It is possible to determine the optimum target dimension for the D dimension, reduce the burden on the operator compared to the conventional method, eliminate variations due to individual differences, and manufacture with consideration for variations in the manufacturing process from a small number of samples. This has the effect of determining the target size.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of the present invention.

FIG. 2 is a system block diagram for executing the processing of FIG.

FIG. 3 is a flowchart showing a more detailed processing procedure of FIG.

FIG. 4 is a flowchart showing a more detailed processing procedure of FIG.

5 is a flowchart showing a more detailed processing procedure of FIG.

FIG. 6 is a flowchart of a random number generation program.

FIG. 7 is an explanatory diagram showing a relationship between a fitting error estimated value and a fitting error target value.

FIG. 8 is an explanatory diagram of factors of spline fitting error.

[Explanation of symbols]

 1 ... Gear measuring machine 2 ... Workstation 3 ... Plotter 4 ... Display

Claims (1)

[Claims] 1. A method for measuring the accuracy of a single spline, statistically processing the measurement results with a computer, and determining the manufacturing target size of the spline from the statistical processing results, which comprises a large number of manufactured shafts. O.D. for each of the splines and hole splines. B. D dimension or B.I. B. A step of measuring accuracy errors of a plurality of items in addition to the D dimension; B. D dimension or B.I. B. A step of obtaining an average value and a standard deviation for each of the D dimension and the accuracy errors of a plurality of items; B. D dimension or B.I. B. A step of extracting a combination of an axial spline and a hole spline with arbitrary accuracy from the D dimension and a distribution of accuracy error variations of a plurality of items, and determining a fitting error for each of a large number of combinations of the axial spline and the hole spline; The process of obtaining the mean value and standard deviation of the fitting error and the fitting required to put the distribution of the fitting error in the range of this fitting error target value based on the target fitting error. Determining the shift amount of the average value of the errors, and O.V. B. Dimension D and B. B. And a step of calculating and outputting an optimum manufacturing target size relating to the D dimension, and a method of controlling the manufacturing target size of the spline.