JPS5845846A - Processing method for workpiece with continuous curved surface - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION In particular, the present invention measures the reference surface of the curved surface using an automatic measurement correction device in advance and calculates the amount of correction so that the thickness or grooves of a workpiece having a continuous curved surface are constant. This paper relates to a processing method using numerically controlled machine tools that performs high-precision processing while adding increase/decrease values.

BACKGROUND ART Conventionally, a method of actually measuring the dimensions of a workpiece and performing correction processing using a numerically controlled machine tool equipped with an automatic measurement correction device is already known, and various products have been commercialized. However, when the workpiece has a continuous curved surface shape, such as a turbine blade, the conventional automatic measurement and correction machining method takes a long time and is inefficient.

That is, in order to improve the measurement accuracy of the automatic measurement correction device, it is better that the operating speed during automatic measurement be as slow as possible, and that the number of measurements be as large as possible. However, this conventional method poses few problems for short workpieces, but for relatively long parts such as turbine blades, it takes a long time to measure, leading to problems such as a decrease in production efficiency. was there.

In addition, when adding an automatic measurement correction function to an existing numerically controlled machine tool, it is desirable to be able to apply it with simple changes or additions to the device, and also to improve operability and workability as functions increase. Therefore, the best solution is to provide a device that has an automatic measurement correction function with a simple configuration and is easy for workers to use, and also leads to the possibility of supplying the device as an inexpensive device.

Furthermore, by adding an automatic measurement correction function, in addition to the normal cutting information, it is possible to select different types of information such as automatic measurement command information and correction cutting information for adding the correction amount processed as a result of measurement. It is necessary to feed the numerical control device in a simple way.

The present invention has been made in view of the above points.

That is, an object of the present invention is to process a workpiece having a continuous curved surface to a constant thickness with high precision. In order to shorten the time, the number of measurement points depending on the workpiece is limited and measured, and the amount of correction between the measurement points is corrected by linear interpolation or circular interpolation. In addition, disparate information by adding an automatic measurement correction function, that is,
Normal cutting information, automatic measurement command information, and corrected cutting information processed after measurement can be determined from a single input information source as before, and it has a continuous curved surface as a simple configuration that is easy for operators to use. The present invention provides a method for processing applied knees.

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.
FIG. 1 is a basic configuration diagram of the present invention.

1 is a machine that cuts a workpiece 2 having a continuous curved surface with a rotating tool 3; 4 is a circular head which can rotate the workpiece 2 around its axis. The movement path and auxiliary operations for machining are determined by input signals 6 from an input information source 5 using paper tape, etc., being sent to each part through processing by a numerical control device 7 while selecting commands 8, automatic measurement commands 9, and machining reference value signals 10. Send.

Commands 811″t, normal cutting commands, automatic measurement operation commands, and correction cutting commands are determined and sent to various servo drive systems of the machine 1.

The automatic measurement command 9 is sent to the measurement processing unit 11 of the arithmetic processing unit 23.
is operated, and by the contact signal 13 of the contact type measuring device 12,
The movement amount signal 15 of the position detector 14 is processed to calculate the actual dimensions (actual measurements) of the workpiece 2. The processing reference value signal 10 is input to the reference value setting section 16, and is input to the measurement processing section 1.
The actual measurement value signal 17 processed in step 1 and the error calculation processing section 18
The reference value setting unit 16 compiles the processed signal 19 so that it can be compared with the reference value setting unit 16. The error value obtained by the error calculation processing section 18 is sent to the next correction value calculation processing section 2 by the signal 20.
1, the correction value is calculated based on linear interpolation or circular interpolation between each measurement point. The correction value signal 2
2, it is sent to the numerical control device 7, and together with the correction cutting command 8, the workpiece 2 is cut while being corrected.

The present invention is configured as described above and operates as follows.

That is, the numerical control device 7 discriminates different types of information based on program instructions from the input information source 5. It is determined from one input information source 5 whether it is normal cutting command information, automatic measurement operation command information, or corrected cutting command information, and a command 8 is given to the machine 1 while skipping unnecessary information for each information. For example, as shown in Table 1, slash codes (/1, /2, etc.) are placed on each block of a program such as an NC tape.
By adding , you can execute a skip signal or subprogram (P9100, P9-200, etc.)
to perform various operations. That is, the subprograms are prepared as various processing programs such as an operation program during automatic measurement, an error value calculation process, a correction value calculation process, a linear interpolation distribution, and a circular interpolation distribution pipe.

When normal-cutting command information is called by the ranked main program, the cutting command 8 causes the machine 1 to operate in the uncut state and performs cutting. Next, when the automatic measurement operation command information is selected, the automatic measurement command 9 is sent to the measurement processing section 11 to start the operation. That is, the contact type measuring device 12 is rotated from the retracted position according to the automatic measurement operation command 8 and operates to the measurement position.

Table 1 Subsequently, the workpiece 2 is moved on each axis and measurement is started according to the measurement operation cycle described later. Based on the contact signal 13, the measurement processing section 11 processes the amount of movement of the position detector 14 to calculate an actual measurement value. In the measurement operation cycle, as shown in FIG. 2, a reference surface B with respect to a processed surface A is measured by a contact type measuring instrument 12. The measurement points on the reference surface of the continuous curved surface are determined by taking into account the size of the workpiece 2, the degree of change in the curved surface, the tolerance, and the measurement time, and are limited to an appropriate number.

In other words, the automatic measurement operation operates to measure only limited measurement points. The movement amount signal 15 based on the contact signal 13 obtained by the automatic measurement operation command 8 is transmitted to the measurement processing unit 1
1, it is processed as the actual measurement value B'1#B'2;..., B'N.

Further, when the automatic measurement operation command 8 is selected, machining information is inputted from the input information source 5 as the machining reference value signal 1o to the reference value setting section 16, and the reference dimension on the program at the measurement point of the automatic measurement operation is Value B1. B2. ...s
The BN is set and provided to the error calculation processing section 18 as comparison information. Subsequently, the error calculation processing section 18 calculates the actual measured value.
” t B'2;...+ B'N and standard dimension value B1.
B21..., BN are compared and calculated, and error values ΔBl, ΔB2, . ..., calculate ΔBN. The signal 2o of the error values ΔB ΔB..., ΔBN is sent to the correction value calculation processor 21, which determines whether linear interpolation is circular interpolation based on the state of the curved surface, and further calculates the difference between the measurement points ( Error value ΔBN-Δ
The interpolation number n1 between BN-x is determined, and each interpolation position nl, n2+..., n with respect to the machined surface A is determined.
A correction value ΔANd of 7Le...+nm is calculated.

That is, correction value ΔANn = X (ΔBN−ΔBN−
Therefore, the number of interpolations can be obtained from the limited number of measurement points by linear interpolation or circular interpolation, and by distributing correction values, it is possible to minimize errors and shorten measurement time.

A signal 22U of each calculated correction value ΔANn is sent to the numerical control device 7 as a tool correction value, and when the correction cutting command 8 is selected from the input information source 5, the machine 1 is activated with the correction value ΔANn added. The workpiece 2 that operates and has a continuous curved surface is cut with high precision so that the thickness is constant.

FIG. 3 is an example of a flow diagram clearly showing a series of operations in which normal cutting command information, automatic measurement operation command information, and corrected cutting command information are selected from a single piece of input information.

According to the present invention, in order to process a workpiece having a continuous curved surface to a constant thickness with high precision, the size of the workpiece,
The positions of the number of measurement points are determined by considering the measurement time based on the degree of change in the curved surface, tolerance, etc., and after measuring the limited measurement points with an automatic measurement device, the error value at each measurement point is calculated by a processing device. The correction value between the measurement points can be subdivided by linear interpolation or circular interpolation to perform correction cutting, making it possible to perform curved surface machining with high precision and shorten measurement time. Ta. In addition, the system uses one input information source as before, and selects normal cutting information, automatic measurement command information, and corrected cutting information from the mixed information, making it easier and simpler for operators to use. It has a simple configuration, and even when added to an existing device, it can be easily applied and provided as an inexpensive device.

As described above, the present invention is not limited to the acupuncture needles shown in the examples, and modifications may be made within the scope of the technical idea of the present invention as described in the claims.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram in one embodiment of the present invention, FIG. 2 is an explanatory diagram showing the contents of correction value calculation processing, and FIG. 3 is a flow diagram in one embodiment of the present invention. In the figure, 1... Machine 2... Workpiece 3... Rotary tool 5
...Input information source 7...Numerical control device 11...
Measurement processing section 12... Contact type measuring instrument 14... Position detector 16... Reference value setting section 18... Error calculation processing section 21... Correction value calculation processing section A... Machined surface
B...Reference plane 23...Arithmetic processing device applicant Hitachi Seiki Co., Ltd.

Claims (1)

[Claims] A machine tool with an automatic measurement correction function uses one side of the workpiece having a continuous curved surface as a reference plane, divides the reference plane into multiple positions along the machining direction, provides measurement points, and performs the multiple measurements. The points are automatically measured continuously by a detector, the measured value calculated as a result of the measurement is compared with a preset value of the curved surface dimension of the workpiece, and the error value of the compared measurement point is used to determine the plurality of points. The curved surface between the divided measuring points is processed by linear interpolation or circular interpolation to allocate the error, and the calculated error value is input as a correction value to the numerical control device, and the correction is performed based on the command of the numerical control device. A method for machining a tlJO workpiece having a continuous curved surface, characterized in that the other surface of the workpiece is machined to adjust the dimensions of the workpiece to a predetermined value according to the value.