JP3200803B2 - Method of manufacturing flat material and method of manufacturing three-dimensional plate material using this method - 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 of manufacturing a flat plate by a method of developing a curved surface of a three-dimensional plate into a flat surface, and a method of manufacturing a three-dimensional plate using this method.

[0002]

2. Description of the Related Art Recently, in the automobile industry, a three-dimensional glass plate is increasingly used as a windshield or a rear glass because of a need for a wide field of view from a driver together with a novel design.

For example, in the prototype stage of a car, a designer first draws a sketch of a new car, creates a somewhat accurate drawing based on the sketch, converts the contents of the drawing into digital values by a digitizer, and converts the drawing into CAD. Captured by the device. The CAD system monitors the three-dimensional shape of the prototype car using the attached high-definition CRT,
Modify the body shape to determine the optimal body shape.
This optimal body shape is prototyped with clay or the like, and then the subtle changes in appearance are further corrected to determine the final three-dimensional shape of the mass-produced vehicle. Of course, drawing
Revised by the device, the digital value is stored in the CAD device and saved to magnetic tape.
The drawing is output as a formal drawing by an XY plotter having a high resolution of 0.1 mm, for example.

For example, in the manufacturing process of a three-dimensionally shaped windshield, only the windshield portion is extracted from a vehicle body prototyped with clay or the like, and furthermore, for economic reasons or shortening of the startup period from trial production to mass production. For this reason, a ring-shaped wooden mold having a three-dimensional surface (curved surface) obtained by copying only the peripheral region of the windshield and having an open central portion is formed. This wooden mold is used not only for forming a mold but also for inspection after molding.

In order to manufacture a windshield for a mass-produced vehicle, it is essential to first use a two-dimensional glass plate having dimensions obtained by developing a three-dimensional windshield as a raw material. The two-dimensional glass plate is formed into a three-dimensional windshield by a forming device.

Heretofore, in order to obtain a two-dimensional development shape of a three-dimensional glass plate, an operator touches paper on a ring-shaped wooden mold having a three-dimensional surface and takes a copy. Since this wooden mold has a ring shape, a three-dimensional shape corresponding to the center of the glass plate is not formed. Therefore, the operator has to press the two-dimensional paper against the wooden mold while keeping in mind the central bulge.

[0007]

It is difficult for an operator to press two-dimensional paper against a wooden mold while keeping in mind the central bulge. In addition, this manual two-dimensional development of a paper contact has a problem that the two-dimensional paper is forcibly applied to a three-dimensional tree pattern to copy the three-dimensional wooden mold, and thus the dimensional accuracy is poor, that is, there are many errors. Further, the three-dimensional glass plate manufactured by this method may be in a state of being undersized or being oversized, and may not fit into a predetermined frame of the vehicle. If the dimensions are not sufficient, the width of the bonding area with the vehicle body becomes narrow, and a predetermined strength may not be obtained.

[0008] Furthermore, the copying operation by hand takes time, and the two-dimensional development operation, which takes much time, cannot be used as input data in the subsequent automatic control process. Therefore, the input data for obtaining the three-dimensional wooden shape must be input again to the computer system for automatic control. The present applicant has addressed these problems in Japanese Patent Application No. 2-4136.
No. 96, "2D expansion method of curved surface of 3D plate using computer system". However, taking the windshield of an automobile as an example, the measured values and calculated values of the peripheral portion intersecting the horizontal and vertical reference lines match well, but the measured values and calculated values of the four corners are different. A slight shift problem occurred. Its value is about 5 millimeters in a two-dimensional shape, but it is fatal in the automobile manufacturing process.

[0009]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a method of expanding a curved surface of a plate material such as a three-dimensional glass plate to which a correction calculation of a peripheral portion is added by using a computer system. In the text, "2D expansion method"
It is an object of the present invention to provide a method of manufacturing a flat plate material according to the present invention and a method of manufacturing a three-dimensionally shaped plate material using this method.

Therefore, according to the present invention, as described in claim 1, (a) the development center point To is determined on the curved surface of the three-dimensionally shaped plate.
It is constant, point contact in (b) and expand the center point To this curved Rights
XZ plane and Y each orthogonal to the plane and orthogonal to each other
Determining the Z plane, to determine the n-th set point Tnm shape line of (c) above curved surface
(Where n and m are positive integers), (d) passing through each of the n-th set points Tnm and the XZ plane
XZm plane and YZn plane which are respectively parallel to YZ plane
It, (e) intersection line Sm between the XZm surface and the curved surface the YZ
An intersection Tn that intersects the plane is found , and this intersection is
The length Ln on the curved surface from the fixed point Tnm is obtained.
Rukoto, (f) intersection line Sn and the YZn surface and the curved surface the XZ
An intersection Tm that intersects the plane is determined, and this intersection is
The length Mn on the above-mentioned curved surface between the fixed point Tnm is obtained.
Rukoto, (g) pro these lengths Ln and Mn on a two-dimensional coordinate
And (h) repeating the above steps (c) to (g) n times
By determining a plurality of development points Dn,
Thus, the calculation of the curve A corresponding to the shape line
It performed using computer system, corresponding to the shape line of the plate of (i) the three-dimensional shape curve A
Calculate the calculated length between the above point and the development center point To.
If, (j) and the point of the shape line of the plate material of the three-dimensional shape, the exhibition
(K) comparing the calculated length with the measured length, and determining that the calculated length is
Correcting the calculated length to match the measured length; (l) a three-dimensional plate based on the corrected calculated length
The two-dimensional unfolded shape of the curved surface of the material is determined, and the determined two
It is characterized by manufacturing flat materials based on the three-dimensional development shape.
It is an object of the present invention to provide a method for manufacturing a flat plate material .

[0011]

1 and 2 schematically show a method of developing a three-dimensionally curved plate two-dimensionally. For example, when an automaker is creating a clay model (clay model) of a prototype vehicle, the three-dimensional shape data Px, y, and z of each part of the model are sequentially input to a CAD device, and the shape is converted to a high-resolution color image. The image is displayed by a cathode ray tube and output as a three-view diagram or a three-dimensional diagram by an XY plotter. The three-dimensional shape data is saved on a magnetic tape. Therefore, the manufacturer of the curved plate (in this case, the windshield) 1 extracts a portion corresponding to the windshield 1 of the three-dimensional shape data in the magnetic tape created by the automobile manufacturer and uses the extracted portion in its CAD device. This is convenient because it saves you from having to enter data. Of course, it is possible to read a portion corresponding to the windshield from the three views by a digitizer and input the read portion to the CAD device.

First, a three-dimensional curved surface 2 corresponding to a windshield 1 is provided on a high-definition color cathode ray tube of a CAD apparatus.
Is displayed. Steps 10 to 24 of developing the three-dimensional curved surface 2 into a two-dimensional shape using a CAD device will be described below.

Step 10: As shown in FIG. 1, one of the curved surfaces 2
The point is defined as the development center point To. This deployment center point To
When the curved surface 2 is symmetrical as shown in FIG. 3 and FIG.
The tangent line e is parallel to a straight line d connecting the upper and lower ends b and c of the curve a. Thus, the deployment center point To
Is set, the inclination direction with respect to the tangent line e of the curved surface 2 from the upper end b to the development center point To is always the same direction, and the inclination direction with respect to the tangent line e from the development center point To to the lower end c is always the same. Since it is the direction, the two-dimensional expansion calculation by the computer is simplified. Further, in the case of a side glass or the like having an asymmetric three-dimensional shape, the development center point To is set at substantially the center of the upper, lower, left, and right sides according to an empirical rule.

Step 11: An XZ plane extending in the horizontal direction passing through the development center point To and a YZ plane extending in the vertical direction passing through the development center point To are obtained. These XZ plane and YZ plane function as reference planes.

In this case, the development center point To is defined as Pxo,
defined as yo and zo. The YZ plane that includes the line symmetry curve a and is orthogonal to the curved surface 2 at the development center point To is orthogonal to the XY plane (not shown) that includes the upper and lower ends b and c of the curved surface a. Since the XY plane is inclined by approximately 30 degrees with respect to the horizontal plane f in the case of the windshield 1 shown in FIGS. 3 and 4, the XY plane is rotated together with the curved surface 2 by approximately 30 degrees with respect to the horizontal plane f. , The XY plane is made substantially coincident with the horizontal plane f. Note that this calculation can be easily performed by a CAD device. Further, the XZ plane is
It passes through the development center point and is orthogonal to the YZ plane and the XY plane. The leveling by rotation may be performed before setting the development center point To when the curved surface 2 is particularly symmetric.

Step 12: Reference intersection lines Sx and Sy at which the XZ plane and the YZ plane passing through the development center point To intersect the curved surface 2, respectively.
Create Therefore, when the curved surface 2 to be two-dimensionally developed is bilaterally symmetric, the intersection line Sy has a line symmetric curve a on the curved surface 2.
Matches.

Step 13: Next, the CAD data corresponding to the windshield 1 includes a shape line of the windshield 1 (an outline of the windshield 1, a heater wire printed on the windshield 1, an antenna wire, or Data about an area where an opaque ceramic color is applied, which functions as a blindfold for a bonding portion with a vehicle body, is stored in advance. Therefore, a curve So corresponding to the inner edge of the ceramic color application area is displayed on the curved surface 2.

Step 14: Specify the n-th set point Tnm on these curves So, ie, Pxn, yn, zn. Here, n and m are positive integers equal to each other (n = m).

Step 15: As in Step 11, an XZm plane extending in the left-right direction through the n-th set point Tnm;
A YZn plane extending vertically through the n-th set point Tnm is determined. However, the XZm plane and the YZn plane correspond to the reference XZ
Plane and the YZ plane, respectively. FIG. 1 shows an XZm plane and a YZn plane passing through the n-th set point Tnm.

Step 16: Similar to Step 12, the XZm plane and the YZn plane at the n-th set point Tnm are curved surfaces 2
Are created, the intersection lines Sm and Sn intersecting each other .

Step 17: An intersection Tn where the intersection line Sy and the intersection line Sm intersect is determined, and the intersection Tn and the n-th set point Tnm are determined.
And the length Ln on the curved surface 2 is determined. The calculation of the length Ln is executed by a subroutine (program) in the CAD device.

The procedure of the subroutine for obtaining the length Ln will be described below. Here, n is a positive integer. First,
An intersection between the intersection line Sy and the intersection line Sm is obtained. These Sy and Sm are

[Number 1] _{S2: P 1 (t) =} [x 1 (t) y 1 (t) z 1 (t)] S3: P 2 (u) = [x 2 (u) y 2 (u) z 2 (U)]

X ₁ (t) = x ₂ (u) y ₁ (t) = y ₂ (u) (0 ≦ t ≦ 1, 0 ≦ u ≦ 1) The intersection Tn is determined by mathematically solving the two unknowns t and u by a method such as the Newton-Raphson method relating to the simultaneous equations.

Next, an intersection Tn between the intersection line Sy and the intersection line Sm
, And a curve Ln on the curved surface 2 between the n-th set point Tnm. This curve Ln is a small-length code.
And the code vector when the parameter changes by Δt is approximately

(Equation 3) The length of this curve Ln when the value of the parameter Δt goes from one end to to the other end tn of the curve Ln is

(Equation 4) Can be calculated by The length of the curve Ln can be obtained by obtaining the solution of this equation by a method such as Gauss' quadrature.

In the CAD device, a screen displaying the three-dimensional shape of the windshield 1 (see FIG. 1).
Is a screen of XY coordinates (coordinates of orthogonal axes) (see FIG. 2)
Can be replaced with the display. The deployment center point To is
This corresponds to the origin Do of the two-dimensional coordinates (XY coordinates).

Step 18: An intersection Tm where the intersection line Sx and the intersection line Sn intersect is determined, and the intersection Tm and the n-th set point Tnm are determined.
And the length Mn on the curved surface 2 is determined. The calculation of the length Mn can be executed by a subroutine (program) in the CAD apparatus as in the case of the step 17, and can be displayed on the screen of the XY coordinates. The calculation procedure for obtaining Mn is the same as the calculation procedure of step 17 except that Ln is Mn, Sm is Sn, Sy is Sx, and Ty is Tx.
This can be done by reading n for Tm.

Step 19: The development point Dn represented by Xn = Ln and Yn = Mn is plotted on the XY coordinates, and the development point Dn is stored. Therefore, the three-dimensional set point Tn
m corresponds to a development point Dn that has been two-dimensionally developed.

Step 20: The above steps 14 to 19 performed for n = 1 are repeated for n = 2, 3 to an integer number of times.

Step 21: Curve A passing through the two-dimensional development point Dn
Create 1. The curve A1 corresponds to a one-dimensionally developed one of the boundary lines of, for example, the ceramic color application region on the three-dimensional windshield 1.
The curve A1 is executed, for example, starting from a point f in the first quadrant, that is, a point f on the reference intersection line Sx shown in FIG.

Step 22: Steps 13 to 21 are repeated by the number of curves A2 to A4 in the second to fourth quadrants. In the case of a symmetrical windshield, for example, the process is repeated for the upper half, the right side, and the lower half of the inner edge of the ceramic color (a boundary line along the outer shape line, for example, 2 cm inside the outer shape of the windshield).

Step 23: The data of these curves A1 to A4 are plotted on an XY plotter. In this case, the curve A1
Forms the two-dimensionally developed shape of the portion of the first quadrant, and the length of the curve A1 from the two-dimensionally developed point F of the point f to the two-dimensionally developed point B of the point b is also calculated.

Step 24: The shape of the curve A1 is very close to the measured value after the reference intersection lines Sx and Sy have been processed into a three-dimensional shape. However, in the corner portion farthest from the reference intersection line, the calculated value and the measured value are shifted by, for example, 5 mm. Thus, for example, the measured length from point f to point b is input to the computer system and compared with the calculated length of the curve A1 from the two-dimensional development points F to B. The computer system gradually expands or gradually shrinks the shape of the curve A1 by fixing the development points F and B from the deviation of the measured length and the calculated length, and matches the measured length with the corrected calculated length. Let it.

That is, when the calculated length is longer than the actually measured length,
As shown in FIG. 8, the point having the maximum correction amount is expanded so as to have a tangent line parallel to the straight line FB, and the corrected curve C1 is obtained.
Ask for. Alternatively, if the calculated length is shorter than the measured length,
The point having the maximum correction amount is deflated so as to have a tangent parallel to the straight line FB. The data of C1 to C4 after the four corner corrections are plotted by an XY plotter.

The sampling interval of the set point Tnm is:
It depends on the radius of curvature of the curved surface 2. That is, the windshield 1
In the case of (1), sampling is usually performed at a pitch of 50 mm, but when the radius of curvature is large, sampling is performed at a pitch of 100 mm. Conversely, if the radius of curvature is small, 50
Sampling can be performed at a pitch smaller than the mm pitch.

FIG. 5 shows a configuration of a CAD apparatus for developing a three-dimensional shape into a two-dimensional shape in the present invention.
In this figure, the shape data of the windshield 1 can be input by digitizing the design drawing 7 with a digitizer 8. Alternatively, shape data can be input by, for example, applying a magnetic tape on which the design data is written to a magnetic tape device 9. Also, a floppy disk can be used instead of a magnetic tape.

The input shape data is stored in the computer 10.
The computer 10 sequentially performs a two-dimensional expansion calculation of a three-dimensional curved surface model corresponding to the shape data of the windshield 1. The progress of the calculation and the result are monitored by a graphic display, that is, a high-definition color CRT 11, numerical data is output by a printer 12, or a display screen of the color CRT 11 is output by a hard copy device 13. The color cathode ray tube 11 and the printer 12 are provided as checking means for the above calculation. The two-dimensional developed shape of the three-dimensional curved surface 2 as the final result has a high resolution XY
Output by the plotter 14. Then, based on the two-dimensional shape, a large number of glass plates having a predetermined shape (such as an outline, a heater wire, an antenna wire, and an inner edge of a ceramic color application area) are manufactured, and then the glass plate is formed by a molding apparatus. The windshield 1 is manufactured by being bent into a three-dimensional shape. The size and the degree of curvature of the windshield 1 are inspected by placing the windshield 1 on a wooden mold.

In FIG. 5, when CAD data is obtained from the design drawing 7, a number of points Q1, Q on the front view and side view of the curved surface 2 called a Mylar diagram as shown in FIG.
2, Q3,... Are designated by the digitizer 8 to take in three-dimensional coordinates. Next, a geometric three-dimensional shape model of the curved surface 2 is created in the computer 10 operating as a CAD system. That is, first, a lattice-shaped three-dimensional spline curve passing through a sequence of points captured by the digitizer 8 is generated, and then the curved surface is divided into quadrilateral patches (surface elements) with the spline curve as a boundary, and the surface is divided along each side of the patch. Create a bicubic parametric surface such as a Coons surface represented by parameters u and v.

In the same manner, a three-dimensional spline curve such as an outline of a glass plate is also generated. Note that a patch of a curved surface can be represented by a Bezier surface, a B-spline curved surface, or the like. When the shape of the curved surface 2 is designed by a CAD system, a three-dimensional model can be obtained from a magnetic tape or the like on which the design data is written.

FIG. 7 is a schematic flowchart of the two-dimensional expansion method shown in FIGS. In FIG. 7, steps 10 to 24 are schematically shown as S10 to S24, respectively.

In this embodiment, for example, a two-dimensional unfolding method used for manufacturing a windshield has been described, but the present invention can also be applied to manufacturing a rear glass or a roof glass. Also,
The present invention can also be applied to manufacture a three-dimensional curved plate from a two-dimensional plate material such as a hard non-ductile hard metal plate (for example, an iron plate) or a plastic plate. Further, as shown in FIG. 2, the case where the set point Tnm is developed on the orthogonal axis coordinates (XY coordinates) has been described, but it may be developed on the polar coordinates.

[0040]

As described above, according to the present invention, since the curved surface of a three-dimensional plate can be developed into a plane by numerical calculation in a computer system, the overall accuracy is improved and the four corners are improved. It has the advantage of improved accuracy, that is, less error. Moreover, since the calculation can be performed by the computer, labor can be saved and time is not required. Further, since the numerical data of the plate material which has been developed two-dimensionally is stored in the computer, it can be used as data of a subsequent process.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a curved surface schematically illustrating a two-dimensional expansion method according to the present invention.

FIG. 2 is an XY coordinate development diagram at a set point of the curved surface in FIG. 1;

3 is a plan view of the right half of the windshield of applying a two-dimensional development method according to the present invention.

FIG. 4 is a side view of the windshield of FIG.

FIG. 5 is a schematic block diagram of a CAD apparatus used in the two-dimensional expansion method according to the present invention.

FIG. 6 is a diagram showing the CAD apparatus shown in FIG.
It is the front view and side view of the curved surface 2 when obtaining AD data.

FIG. 7 is a schematic flowchart of the two-dimensional expansion method according to the present invention shown in FIGS. 1 and 2;

FIG. 8 is a schematic plan view showing a curve A obtained by the two-dimensional expansion method according to the present invention and a curve C after correction.

[Explanation of symbols]

 2 Curved surface To development center point Tnm nth set point Dn nth development point A curve C Curve after correction

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G06F 17/50 B60J 1/00 C03B 23/023

Claims (4)

(57) [Claims] (A) determining a development center point To on a curved surface of a three-dimensionally shaped plate; (b) orthogonal to a plane that makes point contact with the curved surface and the development center point To and orthogonal to each other; XZ plane and Y
(C) determining an n-th set point Tnm on the shape line of the curved surface (where n and m are positive integers); (d) passing through each of the n-th set points Tnm determining the respective parallel XZm surface and YZn surface and the XZ plane and YZ plane with, (e) the intersection line S m and the XZm surface and the curved surface the YZ
Seeking intersection Tn intersecting the plane, to determine the length Ln on the curved surface between this intersection and the first n setpoint Tnm, the intersection line S n and (f) above YZn surface and the curved surface XZ above
Finding an intersection Tm that intersects the surface and finding a length Mn on the curved surface between this intersection and the n-th set point Tnm. (G) These lengths Ln and Mn are represented on two-dimensional coordinates. Plotting to determine the n-th development point Dn; (h) repeating the operations of the above steps (c) to (g) n times to determine a plurality of development points Dn, respectively, A computer system is used to obtain a corresponding curve A, and (i) a curve A corresponding to the shape line of the three-dimensional plate material
Calculate the calculated length between the above point and the development center point To.
If, (j) and the point of the shape line of the plate material of the three-dimensional shape, the exhibition
(K) comparing the calculated length with the measured length, and determining that the calculated length is
Correcting the calculated length to match the measured length; (l) a three-dimensional plate based on the corrected calculated length
Determine the two-dimensional unfolded shape of the curved surface of the material, and manufacture a flat plate based on the determined two-dimensional unfolded shape
A method of manufacturing a flat plate material. 2. The method according to claim 1, wherein the plate is a glass plate. 3. A flat plate manufactured by the method for manufacturing a flat plate according to claim 1 is deformed by heating.
A method of manufacturing a three-dimensionally shaped plate, comprising manufacturing a three-dimensionally shaped plate. 4. The method for producing a three-dimensionally shaped plate according to claim 3, wherein said plate is a glass plate.