JPH05233047A - Automatic programming device for numerical control - Google Patents

Abstract

PURPOSE:To smoothly change the locus of a tool by executing an approach processing based on an approach condition and the arithmetic result of an arithmetic part and smoothing the locus of the tool based on data from a retraction processing part. CONSTITUTION:An arithmetic part 102 calculates the normal direction of a work plane or a tool moving direction based on work shape data and tool locus moving direction data inputted from an input part 101. An approach processing part 103 executes the approach processing based on the approach condition from the input part 101 and the arithmetic result of the arithmetic part 102. A retraction processing part 104 executes a retraction processing based on a retraction condition from the input part 101 and the data from the approach processing part 103. An interpolation part 105 interpolates the data from the retraction processing part 104, and these interpolated data are converted to data for numerical controller and outputted by an output part 106. Thus, the tool locus can be smoothed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic programming device for numerical control.

[0002]

2. Description of the Related Art In the case of using a machine tool to cut an object to be cut into a predetermined shape, a cutting tool is moved to scrape off a portion intersecting with the object to finally make a predetermined shape.

Recently, a machine tool having a numerical control function by a computer has been widely used in order to automatically perform a work and improve a machining accuracy. In a machine tool having a numerical control function, approach and retraction instructions are programmed in advance by an operator, and the tool moves according to the program. Further, an automatic programming device for numerical control, which automatically creates a program by instructing the trajectory of a tool, has also been installed.

In a conventional automatic programming device for numerical control, a tool such as a ball end mill is used to move a tool in a certain direction when approaching or retracting a curved surface on a workpiece. I was setting the trajectory.

[0005]

The most important relationship between the machining accuracy and the movement of the cutting tool is that an error occurs due to a delay of the servo system or the like between the instructed tool path and the actual tool path. .. The magnitude of this error varies depending on the degree to which the tool trajectory changes in direction, and as shown in FIG. 6, it increases as the tool trajectory changes significantly. In order to suppress this error as much as possible, it is desirable that the trajectory of the tool changes smoothly.

However, in the above-mentioned conventional example, since the tool is moved in a fixed direction at the time of approach or retraction, the direction change of the tool locus may be large, which causes a large dimensional error. There was an inconvenience.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic programming device for numerical control capable of improving the disadvantages of the conventional example, in particular, smoothly changing the trajectory of the tool to improve the machining accuracy. ..

[0008]

Therefore, in the present invention, an input section for inputting various data and conditions, and a direction of a machining surface and a tool movement based on machining shape data and tool locus movement direction data from the input section. A calculation unit that calculates the direction, etc., an approach processing unit that performs approach processing based on the approach condition from the input unit and the calculation result of the calculation unit, and smooths the tool path based on the data from the retraction processing unit. It has a configuration including an interpolating unit and an output unit for converting data from the interpolating unit into data for a numerical control device. This aims to achieve the above-mentioned object.

[0009]

The operator inputs machining shape data, tool trajectory movement direction data, approach conditions and retraction conditions into the input section. The input unit outputs the machining shape data and the tool trajectory movement direction data to the calculation unit, the approach condition to the approach processing unit, and the retraction condition to the retraction processing unit. The calculation unit calculates the normal direction of the machining surface, the tool movement direction, etc. based on the machining shape data and the tool trajectory movement direction data from the input unit, creates internal data, and outputs it to the approach processing unit. The approach processing section determines whether or not the data is the approach position data based on the internal data from the calculation section. When it is determined that the data is the approach position data, the three-dimensional approach direction, that is, the approach start position, the approach approach start position, and the respective traveling direction vectors are calculated based on the internal data from the calculation unit and the approach condition from the input unit. At the same time, the calculation result is added to the front of the internal data from the calculation unit and output to the retraction processing unit.

On the other hand, when it is determined that the data is not the approach position data, the internal data from the arithmetic unit is directly output to the retraction processing unit. The retraction processing unit outputs the internal data from the approach processing unit to the interpolation unit and determines whether the internal data from the approach processing unit is data at the retraction position. When it is determined that the data is the data of the retraction position, the three-dimensional retraction direction is calculated based on the internal data from the approach processing unit and the retraction condition from the input unit, and the calculation result is output to the interpolation unit. On the other hand, if it is determined that the data is not the data of the retraction position, nothing is done.

In the interpolator, if the internal data from the retraction processor is the approach position data, the trajectory data to the approach position is gradually changed from the approach approach start position to the approach start position based on the calculation result of the approach processor. The internal data is interpolated so that the direction changes to and output to the output unit. Further, if the internal data from the retraction processing unit is the data of the retraction position, the trajectory data to the retraction position is gradually changed from the retraction progress position to the retraction end position based on the calculation result in the retraction processing unit. The internal data is interpolated so that the direction changes to and output to the output unit. The output unit converts the data from the interpolation unit into data for the numerical control device and outputs it.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.

The embodiment shown in FIG. 1 is based on an input unit 101 for inputting machining shape data, tool trajectory movement direction data, approach conditions and retraction conditions, and machining geometry data and tool trajectory movement direction data from the input unit 101. Calculation unit 102 for calculating the normal direction of the machining surface, the tool movement direction, etc.
And the approach condition from the input unit 101 and the calculation unit 102
The approach processing unit 103 that performs the approach processing based on the calculation result of the
And an interpolation unit 105 that interpolates the data from the retraction processing unit 104, and an output unit 106 that converts the data from the interpolation unit 105 into data for a numerical control device.

Next, the operation of this embodiment will be described.

.. The operator inputs machining shape data, tool trajectory movement direction data, approach conditions and retraction conditions into the input unit 101.

.. The input unit 101 outputs the machining shape data and the tool trajectory movement direction data to the calculation unit 102, the approach condition to the approach processing unit 103, and the retraction condition to the retraction processing unit 104.

.. The calculation unit 102 calculates the normal direction of the machining surface, the tool movement direction, and the like based on the machining shape data and the tool trajectory movement direction data from the input unit 101, creates internal data, and outputs it to the approach processing unit 103. ..

.. The approach processing unit 103 determines whether or not the data is the approach position data based on the internal data from the calculation unit 102 (step 21 in FIG. 2).

When it is determined that the data is the approach position data, the three-dimensional approach direction, that is, the approach start position and the approach approach start position, respectively, based on the internal data from the calculation unit 102 and the approach condition from the input unit 101. Is calculated and the calculation result is added to the front of the internal data from the calculation unit 102 and output to the retraction processing unit 104 (step 22 in FIG. 2).

Here, the calculation method and the output procedure of the approach start position, the approach approach start position, and the approach direction vectors of each approach will be described in detail. However, as shown in FIG. 3, s1 is the curved surface to be processed, p1 is the approach position, n1 is the normal direction vector of s1 at p1, and v
1 is the advancing direction vector of the tool path indicated by the tangent vector of the curved surface, and d is the approach amount specified by the approach condition from the operator.

(A). The approach start position ap1 is calculated from the following formula (1), and the approach start position ap is calculated from the formula (2).
The traveling direction vector av1 in 1 is obtained.

Ap1 = p1 + d × n1 (1)

Av1 = −v1 (2)

(B). It outputs ap1 and av1 to the retraction processing unit 104.

(C). The approach approach start position ap2 is calculated from the following expression (3), and the traveling direction vector a at the approach approach start position ap2 is calculated from the expressions (4) and (5).
Find v2 and av22.

Ap2 = p1 + d × n1-d × v1 (3)

Av2 = −v1 (4)

Av22 = −n1 (5)

(D). It outputs ap2 and av2 to the retraction processing unit 104.

(E). It outputs ap2 and av22 to the retraction processing unit 104.

(F). The internal data from the calculation unit 102 is output to the retraction processing unit 104.

On the other hand, when it is determined that the data is not the approach position data, the internal data from the arithmetic unit 102 is directly output to the retraction processing unit 104 (step 23 in FIG. 2).

.. The retraction processing unit 104 converts the internal data from the approach processing unit 103 into the interpolation unit 105.
(Step 41 in FIG. 4) and it is determined whether the internal data from the approach processing unit 103 is data at the retraction position (step 4 in FIG. 4).
2).

When it is judged that the data is the data of the retraction position, the three-dimensional retraction direction is calculated based on the internal data from the approach processing unit 103 and the retraction condition from the input unit 101, and the calculation result is obtained. Is output to the interpolation unit 105 (step 4 in FIG. 4).
3).

The calculation method and the output procedure of the retraction end position and the retraction advance position and the advancing direction vector at each position will be described in detail. As shown in FIG. 5, s2 is the curved surface to be machined, p2 is the retraction position, n2 is the normal direction vector of s2 at p2, v2 is the advancing direction vector of the tool locus indicated by the tangent vector of the curved surface, d Is the retraction amount specified in the retraction condition. However, here, the position and the vector are assumed to have three-dimensional components.

(A). The retraction traveling position rp1 is calculated from the following equation (6), and the traveling direction vectors rv1 and rv11 at the retraction traveling position rp1 are calculated from the equation (7).
Ask for.

Rp1 = p2 + d × n2 + d × v2 (6)

Rv1 = −v2 (7)

(B). The rp1 and rv1 are output to the interpolation unit 105.

(C). rp1 and rv11 are interpolated by 105
Output to.

(D). The retraction end position rp2 is obtained from the following formula (8), and the traveling direction vector rv2 at the retraction end position rp2 is obtained from the formula (9).

Rp2 = p2 + d × n2 (8)

Rv2 = −n2 (9)

(E). It outputs rp2 and rv2 to the interpolation unit 105.

On the other hand, if it is determined that the data is not the data of the retraction position, nothing is done.

.. If the internal data from the retraction processing unit 104 is data at the approach position, the interpolation unit 105 interpolates the internal data based on the calculation result of the approach processing unit 103 and outputs the interpolated data to the output unit 106. That is, the trajectory data to the approach position is interpolated so as to move the tool while gradually changing the direction from the approach approach start position to the approach start position.

If the internal data from the retraction processing unit 104 is data at the retraction position, the internal data is interpolated based on the calculation result in the retraction processing unit 104 and output to the output unit 106. That is, the trajectory data to the retraction position is interpolated so as to move the tool while gradually changing the direction from the retraction advance position to the retraction end position.

.. The output unit 106 converts the data from the interpolation unit 105 into data for the numerical control device and outputs the data.

[0049]

Since the present invention is constructed and functions as described above, according to this, for example, the trajectory of the tool can be automatically changed smoothly in the vicinity of the approach position, which improves the machining accuracy. It is possible to provide an excellent automatic programming device for numerical control which is not possible in the past.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of an approach processing unit in FIG.

FIG. 3 is an explanatory diagram for explaining an operation of an approach processing unit in FIG.

FIG. 4 is a flowchart for explaining the operation of the retraction processing unit in FIG.

5 is an explanatory diagram for explaining the operation of the retraction processing unit in FIG. 1. FIG.

FIG. 6 is an explanatory diagram for explaining a direction change of a tool path.

[Explanation of symbols]

 101: Input unit 102: Arithmetic unit 103: Approach processing unit 104: Retraction processing unit 105: Interpolation unit 106: Output unit

Claims (2)

[Claims] 1. An input unit for inputting various data and conditions,
Based on the machining shape data and the tool trajectory movement direction data from the input unit, a calculation unit that calculates the direction of the machining surface, the direction of tool movement, and the like, based on the approach condition from the input unit and the calculation result of the calculation unit. Approach processing section for performing approach processing according to the above, an interpolation section for smoothing a tool path based on data from the retraction processing section, and an output section for converting data from the interpolation section into data for a numerical controller. An automatic programming device for numerical control, which is equipped with and. 2. An input unit for inputting various data and conditions,
Based on the machining shape data and the tool trajectory movement direction data from the input unit, a calculation unit that calculates the direction of the machining surface, the direction of tool movement, and the like, based on the approach condition from the input unit and the calculation result of the calculation unit. And a retraction processing unit that performs retraction processing based on the retraction condition from the input unit and the data from the approach processing unit, and the data from the retraction processing unit. An automatic programming device for numerical control, comprising: an interpolating part for smoothing a tool path based on the above, and an output part for converting data from the interpolating part into data for a numerical control device.