JPH1114341A - Bending shape measuring method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce man-hour and improve safety, and also enable high-accuracy measurement by finding the bending radius of a plate piece according to the clearance distance between the punch tip surface and the plate piece and the contact-to-contact distance. SOLUTION: When a punch 1 in which the bottom is flat and the corner parts are rounded (R) is forced downward and free bending forming for a specimen 3 positioned between the punch 1 and a die 2 is advanced, a clearance 7 is produced between the tip surface of the punch 1 and the specimen 3. The length of the clearance 7 is measured by a laser displacement meter 4 embedded in the center of the punch 1. The corner part of the punch 1 is rounded, and the punch bottom length (contact-to-contact distance between the punch 1 and the specimen 3) varied with the indentation of the punch 1 is measured from the bending angle of the specimen 3. According to the obtained clearance distance between the punch 1 end surface and the specimen 3 and the contact-to- contact distance, the bending radius of the specimen 3 is found. Accordingly, high-accuracy shape measurement is enabled in real time during bending formation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for measuring a bent shape, and is useful, for example, for measuring a bent shape at the time of forming a body plate such as a pressure vessel or a container for industrial equipment.

[0002]

2. Description of the Related Art In a conventional shape measurement at the time of bending using a measuring jig, a punch is raised at the end of the bending, and a measuring jig prepared by using a plate, a cardboard or the like conforming to a target bending shape. Is applied to the molded article, and the bending shape of the molded article is measured by observing the gap between the measuring jig and the molded article generated at this time.

[0003]

However, the above-mentioned conventional bending shape measuring method has the following problems.

(1) In order to perform the measurement, it is necessary to raise the punch, which requires a lot of man-hours. (2) There is also a problem in terms of safety due to the work performed by human hands during molding. (3) Every time the shape of the molded product changes, it is necessary to manufacture a measuring jig, and the manufacturing man-hours are also required.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method and an apparatus for measuring a bent shape capable of reducing man-hours and improving safety and performing accurate bent shape measurement. And

[0006]

A method of measuring a bent shape according to the present invention, which solves the above-mentioned problems, comprises a device for bending a plate material located between the die and the punch by a relative movement between the die and the punch. A method for measuring a bent shape of a bent plate material, wherein a bending radius of the plate material is obtained based on a gap distance between a tip end surface of the punch and the plate material, and a distance between contacts between the punch and the plate material. It is characterized by the following.

Further, in the bending shape measuring apparatus according to the present invention for solving the above-mentioned problems, the bending is performed by a device for bending a plate material located between the die and the punch by a relative movement between the die and the punch. A bending shape measuring device for a plate material, wherein a bending radius of the plate material is obtained based on a gap distance between a tip end surface of the punch and the plate material, and a contact distance between the punch and the plate material. It is characterized by.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a conceptual diagram of a method and an apparatus for measuring a bent shape according to an embodiment of the present invention. FIG. 1 (a) is a front view, and FIG. 1 (b) is a side sectional view. FIG. 2 is a conceptual diagram of each processing dimension at the time of free bending with a punch and a die.
Fig. 4 is a diagram showing a state of free bending by a punch and a die (perspective view), and Fig. 4 is a diagram showing a state of a moment distribution during free bending by a punch and a die.

<Structure> As shown in FIG. 1, a bending shape measuring method and apparatus according to the present embodiment are capable of relative movement between a punch 1 and a die 2 having a flat bottom. Specimen (plate material) by pushing punch 1 down)
In the free bending forming of the punch 3, the gap distance between the tip surface (bottom surface) of the punch 1 and the specimen 3 generated during the forming is continuously measured, and the gap distance and the punch bottom length (punch 1) are measured.
The bending shape is automatically measured by calculating the bending radius of the specimen 3 on the basis of the distance between the contact point of the specimen 3 and the specimen 3, and specifically has the following configuration.

As shown in FIG. 1, a laser displacement gauge 4 is embedded and fixed in the center of a punch 1 having a flat bottom and a rounded corner (R). Thus, the laser displacement meter 4
Embedded in the punch 1, the laser displacement meter 4 is much smaller than the punch 1, so there is no need to worry about the deformation of the punch 1 during molding.

As the punch 1 is pushed downward and free bending of the test piece 3 located between the punch 1 and the die 2 is advanced, the gap between the tip end face of the punch 1 and the test piece 3 is increased. A gap 7 is created. Therefore, the distance measurement of the gap 7 is performed using the laser displacement meter 4 embedded in the punch 1. In the figure, reference numeral 5 denotes a laser beam emitted from the laser displacement meter 4 to the surface of the specimen 3.

As shown in FIG. 2, R is formed at the corner of the punch 1 so that the punch bottom length c (the distance between the contact point between the punch 1 and the specimen 3) depends on the amount of the punch 1 pressed. distance)
Therefore, in the present embodiment, the punch bottom length c is obtained by measuring the bending angle of the specimen 3 with the inclinometer 8 provided on the upper surface of the end of the specimen 1.

That is, the punch bottom length c is obtained by the following equation (1). In the equation (1), x is the length of the straight portion at the bottom of the punch, R is the radius of the corner of the punch, α1 is the value measured by the inclinometer 8, and h is the gap distance between the tip surface of the punch 1 and the specimen 3. is there.

C = 2 (R · sin (α1) + x) (1)

The gap distance h between the tip end face of the punch 1 and the test piece 3 measured by the laser displacement meter 4 is given by the following equation (2) based on the bending radius r of the test piece 3 and the punch bottom length c. ).

[0017]

(Equation 1)

Therefore, from the equation (2), the bending radius r is expressed by the following equation (3).

[0019]

(Equation 2)

Therefore, the laser displacement meter 4
Distance h between the tip end surface of the punch 1 and the test piece 3 measured by the bending angle α1 measured by the inclinometer 8
Substituting the punch bottom length c obtained from the above (1) based on the above, obtains the bending radius r of the specimen 3.

The shape after the spring back is measured at a position where the punch load after the lift of the punch is 0 kgf / mm ² .

<Operation / Effect> A punch 1 as shown in FIG.
When the test piece 3 is bent by an apparatus provided with the die of the die 2 and the die 2, a uniform moment distribution can be obtained at the bottom of the punch as shown in FIG. By obtaining such a uniform moment, it is possible to obtain a uniform curvature in this portion.

Therefore, in the present embodiment, the gap distance h between the tip end surface of the punch 1 and the test piece 3 is measured by the laser displacement meter 4 for the test piece 3 bent uniformly by the mold.
, The bending angle α1 of the specimen 3 is measured by the inclinometer 8, and the punch bottom length c is obtained from the above equation (1) based on the bending angle α1, and the gap distance h and the punch bottom length are obtained. By calculating the bending radius r of the specimen 3 from the above c and the above equation (3), the bending shape of the specimen 3 can be measured.

That is, since a total of three positions, that is, one measurement point of the gap distance and two points where the punch 1 and the specimen 3 are in contact with each other are known, a circle (radius) passing through these three points is obtained. Thereby, the shape of the bent portion of the specimen 3 can be measured.

The following results were obtained by actually performing the bending shape measurement by the above method. That is, a SUS30 having a thickness of 10 mm and a width of 80 mm is composed of a punch having a punch bottom length c of 40 mm and a die having a die interval of 60 mm.
After bending the four plates to a radius of 200 mm, this SUS3
As a result of measuring the shape of the 04 plate by the above bending shape measuring method, the measured gap distance h was 0.92 mm, and the length of the punch bottom (the distance between the contacts between the punch and the SUS304 plate) c was 38.3 mm. The bending radius r is 199.
756 mm.

As described above, according to the method and apparatus for measuring a bent shape according to the present embodiment, it is possible to measure a bent shape with high accuracy in real time during bending.

The shape after the spring back can be measured at a position where the punch load is 0 kgf / mm ² .

Since the above effects can be obtained, the number of steps can be reduced and the safety aspect can be improved.

In the above description, the case where a laser displacement meter is used for measuring the gap distance has been described. However, the present invention is not limited to this, and another measuring device may be used. For example,
A dial gauge can also be used.

In the above description, the measurement of the gap distance is measured at only one point. If there is any error in this measurement, an answer of an incorrect shape is given. Therefore, the laser displacement meter 4 is set in a direction perpendicular to the paper surface of FIG.
(B), the laser displacement gauge 4 is moved in the same direction so that the tip surface of the punch 1 and the specimen 3 can be moved in the same direction.
Can be continuously measured and a large number of points can be measured, so that more accurate measurement can be performed than at the time of measuring one point.

[0031]

As described above, the bending shape measuring method according to the present invention is positioned between the die and the punch by the relative movement between the die and the punch, as specifically described with the embodiments of the present invention. A method for measuring the bending shape of a plate material bent by a device for bending a plate material, based on a gap distance between a tip end surface of the punch and the plate material, and a distance between contacts between the punch and the plate material, A bending radius of the plate material is obtained.

Further, the bending shape measuring apparatus of the present invention measures a bending shape of a plate material bent by an apparatus for bending a plate material located between the die and the punch by a relative movement between the die and the punch. The apparatus is characterized in that a bending radius of the plate is obtained based on a gap distance between a tip end surface of the punch and the plate and a distance between contacts between the punch and the plate.

Therefore, according to the method and the apparatus for measuring a bent shape, it is possible to measure the bent shape with high accuracy in real time during the bending.

Regarding the shape after the spring back, the measurement can be performed at the position of the punch load of 0 kgf / mm ² .

Since the above effects can be obtained, the number of steps can be reduced and the safety can be improved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a bending shape measuring method and an apparatus therefor according to an embodiment of the present invention, wherein (a) is a front view and (b) is a side sectional view.

FIG. 2 is a conceptual diagram of each processing dimension at the time of free bending by a punch and a die.

FIG. 3 is a free bending state diagram (perspective view) using a punch and a die.

FIG. 4 is a view showing a moment distribution state at the time of free bending by a punch and a die.

[Explanation of symbols]

 Reference Signs List 1 punch 2 die 3 test piece 4 laser displacement meter 5 laser beam 7 gap 8 inclinometer

Claims (2)

[Claims] 1. A method for measuring a bent shape of a plate material bent by an apparatus for bending a plate material located between the die and the punch by a relative movement between the die and the punch, wherein a tip of the punch is provided. A bending shape measuring method, wherein a bending radius of the plate material is obtained based on a gap distance between a surface and the plate material and a distance between contact points between the punch and the plate material. 2. A bending shape measuring device for a plate material bent by a device for bending a plate material located between the die and the punch by a relative movement between the die and the punch, wherein a tip of the punch is provided. A bending shape measuring apparatus characterized in that a bending radius of the plate material is obtained based on a gap distance between a surface and the plate material and a distance between contact points between the punch and the plate material.