JPS6339325B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a processing method for forming the outline of a sign board such as a road sign into an arcuate cross-section from the viewpoint of safety and strength.

In conventional processing methods, when a circular substrate is used, a tray-shaped metal substrate with a convex edge formed on the contour is placed on a turntable facing upward, as disclosed in Japanese Patent Publication No. 52-36513, for example. The board is pressed and fixed and rotated, and a pressure roller applies strong pressure from above to apply a concentrated load, and the board is rolled in a ring shape along its outer periphery, dispersing and removing strain in the direction of the outer periphery.
A method is employed in which the convex edge of the substrate is shaped into an arcuate cross-section toward the center of the substrate by pressing the convex edge of the substrate through receiving rollers and curl rollers that are positioned on both sides of the convex edge. however,
This processing method not only cannot be applied to polygonal substrates, but also requires time to process (about 1 minute is required) and tends to cause distortion because it is sandwiched between receiving rollers and curl rollers and gradually formed into an arc shape. However, there is a drawback that strain cannot be removed sufficiently using the pressure roller alone.

In addition, when using a polygonal substrate, for example, as disclosed in Japanese Patent Publication No. 52-36514, a tray-shaped metal substrate with a convex edge formed on the contour is turned upward and has a substantially circular cross section. Insert the corner part vertically into the lower mold having an arcuate protrusion, and
The convex edge of the corner is locally formed into an arcuate cross-section by rolling down with an upper die provided with a U-shaped groove. After all the corners have been processed in this way, the substrate is held vertically again. The U is inserted into a lower mold having a substantially arc-shaped protrusion in cross section with one side of the straight contour facing upward.
There is a method in which the entire contour is machined by locally forming a convex edge into an arcuate cross-section for each linear contour by rolling it down with an upper die provided with a mold groove. However, this method has the disadvantage that, for example, eight steps are required to process the convex edges of a square substrate contour, resulting in extremely low productivity and high manufacturing costs.

The present invention eliminates the drawbacks of the above conventional methods,
Regardless of whether a circular substrate or a polygonal substrate is used, the convex edge of the contour can be formed into an arcuate cross-sectional shape in a single press operation and in a short time, and the shape of the contour can be kept constant. The object of the present invention is to provide a processing method that is easy to use and does not easily cause distortion.

Embodiments of the method of the present invention will be described in detail below based on the drawings.

The metal substrate A is obtained by punching a band-shaped material into an arbitrary planar shape using a press, and then forming it into a tray shape having a convex edge B on the outline as shown in FIG. 1 using a press. In FIG. 1, a circular one is illustrated.

The press apparatus used in the method of the present invention is illustrated in FIG. 2 and below.
1, an appropriate number of upper mold set pins 2 stand upright on the outer periphery thereof, and the substrate A is placed on the receiving seat 11.

Reference numeral 3 denotes an upper mold that moves up and down along the set pin 2, and an annular arcuate contour forming mold 4 is formed at the lower part to press and bend the convex edge B of the substrate A in an arcuate cross-section toward the center of the substrate A; is the tsuba 61 of the lifting pedestal 6.
A split type core 5 supported by is provided. The lifting pedestal 6 has a guide hole 31 in the center of the upper mold 3.
The upper mold 3 is
The upper mold 3 is suspended so as to be able to rise and fall freely, and its rotation is restricted by a regulating pin 32 on the lower surface of the upper mold 3 that is fitted into a guide hole 63 formed on the upper surface.

As illustrated in FIGS. 4 and 5, the split core 5 forms an annular shape whose overall planar contour is similar to the contour of the substrate A, and is radial when viewed from the center. It is divided into 15 degree intervals. When the target substrate A is polygonal as shown in FIG. 6, the core 5 is divided radially from the center into corner portions of the planar contour and straight portions corresponding to the contour of the substrate A.

The posture of each split mold core 5 is regulated by a regulating pin 51 guided by a guide slit 33 formed toward the outer circumference of the upper mold 3, and a guide formed at the upper part of the arcuate contour forming mold 4. a pusher 7 fitted into the hole 41 and biased by a compression spring 71;
By means of a compression spring 34 interposed between the upper die 3 and the lifting pedestal 6, the substrate A is always maintained in a retracted position when viewed from the contour direction (outer circumferential direction), and the core 5 in this retracted position is The entire planar contour of substrate A
The inner diameter L of the arcuate contour finally formed in (Fig. 1)
It has a smaller diameter. The bottom outer periphery of each split core 5 has a flange-shaped abutment portion 5 whose top end is formed into an arcuate cross-section.
2 is formed, and its back surface is in oblique contact with a regulation block 8 having a wedge-shaped cross section protruding from the lower surface of the upper die 3. When the upper die 3 descends and presses the substrate A,
Each core 5 moves forward in the direction of the contour of the substrate A by means of the regulating block 8 until the abutment portion 52 abuts the inner base of the convex edge B of the substrate A. Due to this forward movement, the split core 5 as a whole expands from the state shown in FIG. 4 to the state shown in FIG. 5.

In the above apparatus, when the upper mold 3 is lowered from the state shown in FIG. 2 and pressure is applied to the substrate A, each split mold core 5 advances as shown in FIG. 3, and the arcuate profile forming mold 4 descends. As shown in the figure, the convex edge B of the substrate A is formed in an arc shape toward the center. When the upper mold 3 is raised from the state shown in FIG. It retreats to the position shown in Figure 2 and rises without interfering with the convex edge B of the substrate A formed in an arc shape.

In order to move the split core 5 forward and backward as described above, instead of configuring it as in the embodiment described above,
For example, a guide bar (not shown) is provided on the lower surface of the upper mold 3 toward its outer circumference, the split mold core 5 is supported by this guide bar, and the split mold core 5 is advanced along the guide bar by hydraulic pressure. It can also be carried out by moving backwards.

Further, even if the substrate A has a groove C having an arcuate cross section projecting to the opposite side at the base of the convex edge B, as shown in FIG. 7, the same core 5 can be used.

According to the method of the present invention, a substrate having a convex edge formed on its contour is placed on the substrate receiving seat of the lower die as described above,
Pressure is applied to the substrate using an upper mold provided with an arcuate contour forming mold that presses and bends the convex edge of the substrate inward, and a split mold core that is divided radially from the center in correspondence with the planar contour of the substrate. Since the convex edge can be formed into an arcuate cross-sectional shape with just one press operation, the process of forming the arcuate contour of the sign board is extremely short (5 minutes per board, including setting the board on the receiving seat). ~7 seconds). Furthermore, since the processing is performed in a single press operation, the sign board is less likely to be distorted, and the dimensions and shape of the arcuate contour portion tend to be constant, resulting in stable quality.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the substrate before arcuate contour molding, Fig. 2 is a cross-sectional view showing an example of a press device for carrying out the method of the present invention, and Fig. 3 is a cross-sectional view of the substrate before it is formed into an arcuate profile. 4 is a plan view of the split core in the retracted position in the device; FIG. 5 is a plan view of the split core in the forward position; FIG. 6 is a split diagram showing another embodiment. FIG. 7 is a plan view of the mold core in the advanced position, and a partial sectional view showing the relationship between the substrate and the split mold core in another example. Explanation of main symbols in the figure: A is the board, B is the convex edge of the outline of the board, 1 is the lower mold, 11 is the board receiving seat, 3 is the upper mold, 4 is the arcuate contour forming mold, 5 is the split core It is.

Claims (1)

[Claims] 1. A metal substrate with a convex edge formed upward in the contour part is placed on the substrate receiving seat of the lower mold, and the convex edge of the contour part of the substrate is placed in the lower part toward the center of the substrate. an arcuate profile forming mold for bending under pressure, and a split core having the structure described in the following a to d, which is located inside the arcuate profile forming mold and is divided into substantially radial planes corresponding to the outline of the substrate. A method for processing a contour portion of a sign board, characterized in that the convex edge of the substrate is formed into an arcuate cross-section by pressurizing the substrate with an upper mold that can be raised and lowered. a The split mold core is maintained such that, when the upper die is raised, the overall planar contour is approximately similar to the planar contour of the substrate and is smaller in diameter than the inner diameter of the arcuate contour finally formed on the substrate. (b) Each split type core has a flange-shaped contact portion at the tip facing toward the outer circumference of the substrate, and c) Each of the split type cores comes into contact with the upper surface of the substrate by lowering the upper mold. in this state, the contact portion moves forward from the center direction of the substrate toward the outer circumference until it comes into contact with the inner side of the convex edge of the substrate; After retreating toward the center of the substrate while in contact with the upper surface of the substrate, the substrate moves upward. 2. The method for processing a contour part of a sign board according to claim 1, wherein the substrate is circular and the split core is divided into planes at equal angular intervals. 3. Processing of the contour portion of a sign board according to claim 1, wherein the substrate is polygonal and the split core is divided corresponding to the corner contour portion and the straight line contour portion of the substrate. Method.