JP3148144B2 - Shape calculation method in the pre-process of forged products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for calculating the shape of a forged product from a final shape of a forged product (or an intermediate shape in an intermediate step) to obtain an intermediate shape in an earlier process.

[0002]

2. Description of the Related Art Usually, when a product is manufactured by forging,
Forging work is performed step by step, assuming an intermediate shape in the intermediate process. Conventionally, the intermediate shape has been assumed from the product shape, that is, the final shape after the completion of forging, based on the experience and intuition of a skilled engineer. Of course, the same applies when assuming an intermediate shape in the preceding process from the intermediate shape.

[0003] More specifically, in the forging operation, crushing forging for facilitating the volume distribution from the billet, roughing forging in which preliminary forming is performed using a rough land mold, and final forging using a finishing die. A final forging for performing a typical forming, and a deburring step of punching out outer burrs and inner burrs using a punching die are sequentially performed. Therefore, it is necessary to correctly determine a rough land shape (a shape after rough striking, that is, a shape before finishing striking) from a shape in a previous process, for example, a finished shape (shape after finishing striking).

[0004] When calculating the shape of each forged product in the intermediate step, the final shape of the final product is divided into a plurality of parts along a predetermined direction, for example, the direction in which the forged product extends, and the design is performed for each divided part. The user determines the cross-sectional shape before forging from the relationship established between the cross-sectional shape after forging and the cross-sectional shape before forging (pre-process), and uses the obtained cross-sectional shape for each of the divided parts before forging. The overall shape was required.

[0005]

However, for each divided part of a forged product, it is very troublesome for a designer to determine the shape before forging from the relationship between the cross section after forging and before forging. However, there is a problem that it takes a lot of time, and there is a limit in improving the design efficiency.

As a means for solving these problems, a method of synthesizing the shapes of a plurality of similar products in the previous process can be considered. However, the shape of the new forged product is not reflected, and therefore, the shape during the forging is not reflected. There is a problem that positioning and volume distribution may not be suitable for a new forged product.

[0007] Therefore, the present invention provides a new forging product in which positioning and volume distribution can be easily determined in a short time in a pre-process of a forged product, and by utilizing the features of the shape of the new forged product. It is an object of the present invention to provide a method of calculating a shape in a previous process that matches a product.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, a first means of the present invention is to provide a computer device for changing the shape of a new forged product in a predetermined process to a shape of a new forged product in a previous process.
A method for calculating using, first, a predetermined machining of the new forging
The shape of the known forged product similar to the shape corresponding to the process and the shape in the previous process are searched for from the database , and then the new forged product, the forged product and the forged product are searched. The contours of the cross-sections of the three shapes of the pre-processed product are divided by the same number according to the shape feature such as unevenness, and in each of these divided sections, the new forged product, the forged product, and the forged product Formula based on the difference in the contour shape of the pre-processed product
By combining the contours of the cross section of the pre-processed shape of the new forged product in each section, and connecting the contours in each of the synthesized sections, the pre-processed shape of the forged product is calculated by calculating the pre-processed shape of the new forged product It is a calculation method.

Further, the second means of the present invention, in the configuration of the first means, comprises combining a new forged product, an already-forged product, when synthesizing a sectional profile of a preprocess shape of a new forged product for each section. And the contours of the cross-sections of the three shapes of the pre-processed product of the forged product are converted into point sequence coordinate data, respectively , based on the difference between the radii at the polar coordinates in the coordinate data corresponding to each section of each shape.
The following formula (a) is used to calculate each coordinate data for each section corresponding to the shape of the pre-process of the new forged product, and to synthesize the forged product in the pre-process based on these coordinate data.
It is a calculation method.

R = a × r−b × ρ + c × P (a) (ab + c = 1), where R is the cross-sectional profile of the shape in the previous process of the new forged product.
Radius r in polar coordinates : in polar coordinates in the cross-sectional profile of the shape of the new forging
Radius ρ: half in polar coordinates of the cross-sectional profile of a similar product
Diameter P: pole in cross-sectional profile of similar product in previous process
Coordinate radius a: coefficient of a new forged product b: coefficient of a similar product c: coefficient of a previous process of a similar product .

[0011] A third means of the present invention, in the configuration of the first means, comprises combining a new forged product, an already-forged product, when synthesizing a sectional profile of a preprocess shape of a new forged product for each section. And the contour of the cross section of the three shapes of the pre-processed product of the forged product is divided into a line segment and a circular arc with the same number of elements, respectively, and the following arithmetic expression (b) based on the difference in curvature between the corresponding elements of each shape )
The calculated line segments and arcs of curvature of each element in the previous step the shape of the new forging, the shape calculation method in the previous step forging synthesizing processing line or arc based on this curvature.

1 / R = a × (1 / r) −b (1 / ρ) + c (1 / P) (b) (ab−c = 1), where 1 / R: new forged product Of the cross-sectional profile of the shape in the previous process
Elemental curvature 1 / r: Curvature of the element of the cross-sectional profile of the new forged product 1 / ρ: Curvature of the element of the cross-sectional profile of the similar product 1 / P: Element of the cross-sectional profile of the similar product in the previous process
The curvature of a: coefficient of the new forging b: coefficient of similar products c: is a coefficient of the previous step of similar products.

[0013] The fourth aspect of the present invention, calculates the first through third cross-section obtained by the shape calculating how <br/> method in the previous step of the forged product in means in the form a plurality sectional
And, by the three-dimensional shape by connecting these the obtained cross synthesizing process, the shape calculation method in the previous step of the forged product for calculating a three-dimensional pre-process shape of the new forging.

According to the shape calculation method in each of the above means, when the shape of the new forged product is given, the shape of the forged product stored in advance is compared with the shape of the forged product having a high degree of similarity. Since the shape in the process is selected and the shape in the previous process of the new forged product is synthesized from the three shapes including the new forged product shape, the shape of the new forged product can be very easily and quickly. It can therefore be found to shape in the previous step given a new forging utilizing the features.

Further, by using the shape data in the previous process of the new forged product obtained by each of the above shape calculation methods, in particular, by obtaining the shape data using a computer device and three-dimensional CAD software, A mold can be designed very easily even for a complicated shape.

The shape calculation method according to the first to third means is suitable when the shape of the forged product is an axisymmetric article, and the shape calculation method according to the fourth means is suitable for the shape calculation of the forged product. Are suitable for non-axisymmetric articles.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for calculating a shape of a forged product in a pre-process according to an embodiment of the present invention will be described below with reference to the drawings.

The gist of the present invention is a method of the shape in the previous step of the new forging, Ru determined based on the difference between the already forging shape is known and the shape of its previous step, more specifically In
Enter the shape of the final forged product (hereinafter, referred to as the final forged product) to be subjected to final molding, and change the shape of the forged product in the previous process, that is, the intermediate process, to the billet in the initial process (hereinafter, referred to as the intermediate forged product). (Including a billet) is calculated by a computer device. That is, there is a certain geometric relationship between a certain forged product and the intermediate forged product in the previous process, and by using this relationship, the shape of the intermediate forged product in the previous process is determined. It is based on This shape calculation method is suitable when the shape of the forged product is an axisymmetric product.

Hereinafter, a method of calculating the shape of the forged product in the previous process according to the first embodiment will be described with reference to the flowchart shown in FIG. In the first embodiment, an intermediate forged product from the shape of the final forged product to the billet shape, that is, a shape in the roughing process (hereinafter, referred to as a rough product), a shape in the crushing process (hereinafter, referred to as a rough product). A description will be given of a case in which data of a shape (a billet shape) in an initial process is obtained.

First, a finished shape, which is a final forged product shape, is read (step 1), and the number N of cross sections to be synthesized is determined. In the case, it is the number of cross-sections necessary to represent the entire shape)
After (Step 2), a search range for searching for a similar product similar to the new forged product from the forged product is set (Step 3). This search range is set for the purpose of shortening the search time, and the search can be performed on the entire database D without setting the range.

Next, it is assumed that M = 1 (where M indicates the stage of each process, and its specific value and the process corresponding thereto are described in the database D of FIG. 1) (step 4). Then, a similar product of the new forged product is searched to select a similar product to be used for shape synthesis (step 5).

Next, assuming that K = 1 (where K is a variable for counting the number of sections to be synthesized and is a value from K = 1 to N) (step 6), a new forged product, a selected similar product And reading the contours of three cross-sections (three types) of the pre-processed product of similar products (step 7), and synthesizing the cross-sectional contours in the pre-process of the new forged product based on the contours of the three cross-sections (Step 8). If the new forged product is a non-axisymmetric product, this synthesis process is repeated until the required number of cross sections is reached (step 10). This combining process will be described later in detail.

From the profile of the cross section obtained in this manner, the entire shape of the pre-process of the new forged product is created (if the new forged product is an axisymmetric article, the cross section is rotated to create a non-formed product. In the case of an axisymmetric article, a plurality of cross sections are connected to create an overall shape (step 11).

Further, assuming that M = M + 1 (step 12), the shape synthesis in the previous step is repeated until a billet is obtained (step 13). As described above, all the shapes of the intermediate forged product of the new forged product are obtained and output (Step 1).
4) At the same time, the data is converted into a die-sculpted shape (step 15). In step 16, it is determined whether these shape data are registered as new data in the database D (either automatically or by an operator).

Next, in the above-mentioned series of intermediate forging product shape synthesizing processes, the synthesizing process of the cross-sectional contour shape in the previous step of the new forging product in step 8 will be described in detail based on the flowchart of FIG. I do.

First, J = 1 (J is the number of the contour shape to be processed, J = 1 is a new forged product, J = 2 is a similar product of the new forged product,
As J = 3, the shape of the similar product in the previous process is used (step 1). The dimensionless point sequence coordinate data and the binarized data of the contour shape of the new forged product are read (step 2).

Point sequence coordinate data is a set of coordinate values of each point when points are arranged at predetermined intervals on a contour line represented by a line segment or a curve, and is converted into point sequence coordinate data. Accordingly, the following shape synthesis processing can be performed only by numerical operations that a computer is good at.

The dimensionless point sequence coordinate data is obtained by dividing the coordinate value of each point by the outer radius and height of the cross section and replacing the coordinate system with an outer radius of 1.0 and a height of 1.0. Point sequence coordinate data.

Also, the binarized data means that the cross section is vertical x horizontal =
It is divided into meshes of about 50 × 50, and the shape is represented by the on / off state (1, 0) of this mesh part.
An example is shown in FIG.

Next, the contour shape is divided into sections according to the unevenness of the shape (step 3). The unevenness of the shape and the division position are determined using the binarized data. FIG. 3 shows an example of the division position. In the example of FIG. 3, the outline shape 1 is divided into eight sections as indicated by black circles (division positions) 2. This process is repeated until J = 3 (step 4), and the number of divisions (matching the larger number of divisions) and the division position 2 are adjusted so that the number of divisions of the three shapes is matched (step 6).

As described above, sections corresponding to the three shapes are determined, and the following processing is performed for each section. First, i = 1
(This i is a variable representing the number of the section, i = 1 to L) (step 7), and the three-shaped section [line segment 3 (contour shape of new forged product) in FIG. The left end of 4 (contour shape of similar product) and 5 (contour shape of similar product in the previous process) is point 6 in FIG. 4 (a) [coordinate values are (ξ _i−1 , η)
_i-1 )] at the right end of point 7 [coordinate values are (ξ _i , η
_i )], and coordinate conversion of a point sequence in the section is performed so that both ends of the section are matched (step 8). When this coordinate transformation is expressed by an equation for a new forged product, the following equation (1) is obtained.

[0032]

(Equation 1) Where (x, y): coordinates of an arbitrary point on the contour of the new forged product (x ′, y ′): coordinates (x _i−1 , y _i− ) after coordinate transformation _1): the leftmost coordinate of the coordinate before conversion section (x _i, y _i): the right end coordinate of the coordinate before conversion section _{(ξ i-1, η i} -1): a point to align the left edge coordinates (xi] _i , Η _i ): coordinates of the point where the right end is to be aligned.

A similar product and a pre-process product of the similar product have the same formula [the coordinates of the similar product are the coordinates of the pre-process product of the similar product before the coordinate transformation (u, v) and after the transformation (u ', v')]. Are represented before (U, V) and after (U ′, V ′).

The state after the coordinate conversion is as shown in FIG. In FIG. 4B, 3 'to 7'
FIG. 7A shows the result after the coordinate conversion of 3 to 7 in FIG. The points 6 (ξ _i−1 , η _i−1 ) and 7 (ξ _i , η _i ) at the positions where the end points are aligned are connected to each section of the shape in the previous process of the new forged product after the shape synthesis. There are no other restrictions as long as the conditions are satisfied. In the present embodiment, the coordinate values (ξ _i , η _i ) of the point 7 are determined by the following equation (2) using the coordinate values of the three shape end points and the coefficients a, b, and c.

[0035]

(Equation 2) The coordinate value (ξ _i−1 , η _i−1 ) of the point 6 is determined in the same manner.

Next, the point sequence data after the coordinate conversion is
Using the equation (3), conversion to polar coordinates is performed (step 9).

[0037]

(Equation 3) Where (r, θ) is an arbitrary point (x ′,
y ′) is converted to polar coordinates. Polar coordinates (ρ, φ) of a similar product and polar coordinates (Ρ, Φ) of a pre-processed product of a similar product are similarly obtained (step 9).

The radii r, ρ, Ρ (θ = φ =
Using the value of Φ), the radius R (the angle at this time is Θ = θ) in the previous process of the new forged product is obtained by the following equation (4) (step 10).

[0039]

(Equation 4) However, in the equation (4), a: coefficient of a new forged product b: coefficient of a similar product c: coefficient of a pre-processed product of a similar product By obtaining this R at a predetermined interval of Θ,
Point sequence data by polar coordinate display in the previous process of the new forged product in this section is obtained. This point sequence data is converted in the reverse of the coordinate conversion performed so far, that is, converted into orthogonal coordinates represented by the following equation (5) [the converted coordinate value is defined as (X ′, Y ′)] ( Step 11) Transformation for restoring the end point of the section shown in the following equation (6) [Coordinate values after transformation are set to (X, Y)]
By performing (Step 12), point sequence data in the original coordinate system is obtained.

[0040]

(Equation 5) However, it corresponds to the original position of the right end point of the section (X _i , Y
_i )
It is obtained by equation (7).

[0041]

(Equation 6) The left end point (X _i-1 , Y _i-1 ) is obtained by a similar expression.

The above-described shape synthesis is performed for all divided sections (step 13). Here, FIG. 5 shows a case where the shape calculation method according to the present embodiment is applied to shape synthesis of a rough process product.

FIG. 5A shows the finished shape of a new forged product.
FIG. 5B shows a finished shape of a similar product, and FIG.
Represent the roughing shape which is the pre-process shape of similar products,
5 (d) to 5 (f) show the roughing shape of the synthesized new forged product.

According to the shape synthesizing method, a variety of shapes can be output by changing the values of the coefficients a, b, and c. This coefficient is usually set in advance, but it is possible to change the coefficient by looking at the output result and redo only the shape synthesis.

In the method of synthesizing the shape according to the present embodiment, since the shape of the new forged product is used, it is obvious that the shape of the new forged product is reflected. Since the difference in shape from the previous product is also used, know-how such as positioning, volume distribution, and defect prevention of similar products is inherited.

Incidentally, not only one kind of similar products but also a plurality of similar products can be selected and a plurality of shape synthesis results can be output at the same time. Shape can be selected.

In the first embodiment, first, the contour of the cross section is divided into sections, and each section is made to correspond to a new forged product, a similar product, and a pre-process product of the similar product in a 1: 1: 1 relation. , The point sequence on the contour line is also made to correspond 1: 1: 1.

Next, the shape calculation method according to the second embodiment of the present invention will be described. The difference from the first embodiment is that the method of synthesizing the contour of the cross section of the pre-process shape of the new forged product is different. Therefore, in the second embodiment,
A description will be given focusing on this part.

That is, in the first embodiment, as described above, first, the sectional profile is divided into sections, and each section is divided into a new forged product, a similar product, and a pre-process product of the similar product.
1: 1, and finally the point sequence on the contour line also corresponds to 1: 1: 1. However, the shape calculation method of the second embodiment extends the principle. The outline of the cross-sectional shape is represented by an element composed of a line segment and an arc, and each element is a new forged product, a similar product, and a pre-processed product of a similar product in a ratio of 1: 1: 1.
In this method, the shape of the new forged product in the previous process is obtained based on the following equation (8) using the curvature of each element instead of the radius in equation (4).

[0050]

(Equation 7) Where, 1 / R: the curvature of the element of the cross-sectional profile of the shape in the previous process of the new forged product 1 / r: the curvature of the element of the cross-sectional profile of the new forged product 1 / ρ: similar product 1 / Ρ: Curvature of the element of the cross-sectional profile of the similar product in the previous process.

In the case where the new forged product is an axisymmetric product, the contour shape of the dimensionless cross-section obtained in the preceding process obtained as described above is returned to the original size (returning to the outer radius and height). The cross section is rotated and swept to determine the overall shape.

When the new forging is a non-axisymmetric article,
The cross-sectional area is adjusted in the height direction based on the horizontal dimension of the cross section to return to the original dimension, and the cross section is connected to obtain the entire shape. The reason why the dimensions are adjusted in the outer radius or the horizontal direction of the cross section in this way is to facilitate positioning in the next step (for example, a finishing step is performed in the next step of a rough-hit product).

The shape synthesizing process in the pre-process for these new forged products is performed by using a computer, and by using the finally obtained overall shape data, the shape for obtaining the shapes in the pre-process for the new forged products is obtained. Shape data of the concave shape of the mold can be easily obtained.

[0054]

Effect of the Invention shape Starring in the previous step of the forged product of the present invention
According to the calculation method, when the shape of the new forged product is given, the shape of the forged product stored in advance is compared with the forged product having a high degree of similarity and the shape in the previous process is selected, and Since the shape of the new forged product in the previous process is synthesized and calculated using three shapes including the shape of the new forged product, the characteristics of the shape of the new forged product can be reflected. Problems such as defects are reduced, and correction of the output shape is also reduced.

[0055] Further, since the shape in the previous step at the same time the new forging for a plurality of similar products is output, select suits previous step shape house can be obtained. Further, by using the shape data of the new forging of the previous step determined by the shape calculation method, and <br/> using computer equipment, by calculating the shape data, complex Even in the case of a shape, a mold shape can be designed very easily.

[Brief description of the drawings]

FIG. 1 is a flowchart for obtaining a shape of a forged product in a previous process according to a first embodiment of the present invention.

FIG. 2 is a flowchart for obtaining a contour shape of a cross section during a process of obtaining a shape of a forged product in a previous process according to the first embodiment.

FIG. 3 is a diagram showing a state of a forging product shape processing in the first embodiment.

FIG. 4 is a diagram illustrating coordinate conversion for shape processing of a forged product in the first embodiment.

FIG. 5 is a view showing various shapes and a composite shape thereof in the first embodiment.

[Description of Signs] 1 Outline shape of cross section of forged product 2 Point at which the outline of cross section is divided (division point) 3 Outline shape of new forged product (after section division) 4 Outline shape of similar product (after section division) 5 Similar Contour shape in pre-process of product (after section division) 6 Position to match left end point of section 7 Position to match right end point of section

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-241338 (JP, A) JP-A-7-49899 (JP, A) JP-A-6-344066 (JP, A) Plasticity and processing 36 No. 408, pp. 35-40 Deno Katayama et al., "Study on Intelligent CAD for Process Design in Cold Forging" (58) Fields investigated (Int. Cl. ⁷ , DB name) 5/00 B21J 13/02 JICST file (JOIS)

Claims (4)

(57) [Claims] 1. A method for calculating a shape of a new forged product in a pre-process using a computer device , wherein the shape in a predetermined process corresponds to a predetermined process of a new forged product. Form
The shape of the known forged product similar to the shape and the shape in the previous process are searched for and obtained from the database , and then the three shapes of the new forged product, the forged product, and the preprocessed product of the forged product are obtained. The cross section of the cross section is divided by the same number according to the characteristic portion of the shape such as unevenness, and in each of these divided sections, the contour shape of the new forged product, the forged product, and the pre-processed product of the forged product By combining the contours of the cross section of the pre-process shape of the new forged product for each section using an arithmetic expression based on the difference between the sections and connecting the contours in each of the synthesized sections, the pre-process shape of the new forged product is calculated. A method for calculating the shape of a forged product in the preceding process. 2. When synthesizing the cross-sectional contour of the pre-processed shape of the new forged product for each section, the cross-sectional contours of the three shapes of the new forged product, the forged product, and the pre-processed product of the forged product are each pointed. The following calculation based on the difference of the radius at the polar coordinates in the above coordinate data corresponding to each section of each shape after converting to column coordinate data
2. The pre-process for a forged product according to claim 1, wherein each coordinate data in each section corresponding to the pre-process shape of the new forged product is calculated by the equation (a), and a synthesis process is performed based on the respective coordinate data. Shape calculation method. R = a × r−b × ρ + c × P (a) (ab−c = 1), where R is the cross-sectional profile of the shape in the previous process of the new forged product.
Radius r in polar coordinates : in polar coordinates in the cross-sectional profile of the shape of the new forging
Radius ρ: half in polar coordinates of the cross-sectional profile of a similar product
Diameter P: pole in cross-sectional profile of similar product in previous process
Coordinate radius a: coefficient of a new forged product b: coefficient of a similar product c: coefficient of a previous process of a similar product . 3. When synthesizing the cross-sectional contours of the pre-processed shape of the new forged product for each section, the cross-sectional contours of the three shapes of the new forged product, the forged product, and the pre-processed product of the forged product are respectively lined. The element is divided by the same number into minutes and arcs, and the line and arc of each element in the pre-process shape of the new forged product are calculated by the following arithmetic expression (b) based on the difference in curvature between the corresponding elements of each shape. calculating a curvature, the shape calculation method in the previous step according to claim 1, wherein forgings, characterized in that the line or arc to synthesis processing <br/> based on the curvature. 1 / R = a × (1 / r) −b (1 / ρ) + c (1 / P) (b) (ab−c = 1), where 1 / R: pre-process for new forged product Of the cross-sectional profile of the shape at
Elemental curvature 1 / r: Curvature of the element of the cross-sectional profile of the new forged product 1 / ρ: Curvature of the element of the cross-sectional profile of the similar product 1 / P: Element of the cross-sectional profile of the similar product in the previous process
The curvature of a: coefficient of the new forging b: coefficient of similar products c: is a coefficient of the previous step of similar products. 4. A cross-sectional shape calculated by a shape calculating method in a pre-process of a forged product according to any one of claims 1 to 3 is calculated for a plurality of cross-sections , and these obtained cross-sections are joined. by the dimension shape synthesis process,
Shape calculation method in the forging of the previous step, which comprises calculating the three-dimensional pre-process shape of the new forging.