JPS643638B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for cutting the ends of synthetic resin moldings for decoration and protection that are attached to the side surfaces of automobiles.

The manufacturing method for synthetic resin moldings such as automobile side moldings and bumper moldings involves extrusion molding of synthetic resin together with surface decoration materials such as metal foil and decorative film, cutting it into regular lengths, and finally cutting it into a predetermined shape. The terminal is being processed.

Conventional terminal processing methods include simply cutting off the terminal, but in this case it is not possible to round the end, which poses problems in terms of decoration and safety. In addition, in the method of V-cutting the ends of the molding and thermally bonding the cut surfaces together, as in Japanese Patent Publication No. 51-22954, the V-cut surfaces are melted and bonded, so molten resin protrudes on the bonding line and the appearance In addition to damaging the product, there were also defects that required post-processing. Furthermore, the method of bonding pre-separately molded parts by thermal bonding etc. requires less man-hours for separate molding,
There was also a problem with the combination with extrusion molding. In addition, as in JP-A No. 54-114375, the method of inserting a molding end into an injection mold and performing injection molding to obtain a predetermined end shape is based on minute errors in extrusion molding and mold shape. However, the resin leaked out during injection molding, damaging the appearance and requiring post-processing. And JP-A-54
-8674, a method in which a jig formed into a predetermined shape is pressed while being heated with high frequency is also known, but in this method, the heated jig is pressed and processed, so the jig and molding are There were drawbacks such as melting of the molten resin from the interface and changes in the color and gloss of the processed surface due to reheating.

The present invention eliminates the drawbacks of the conventional method as described above,
The purpose of the present invention is to propose a method and apparatus for cutting the ends of synthetic resin, which can give rounded ends only by cutting the ends.

The present invention includes the following two inventions.

(1) In a method of cutting the long end portion of a long synthetic resin molding with an irregular cross section, the portion of the molding to be cut is pressed from the outside surface side so that the outside surface is uniform. It is characterized by stretching the molding until it undergoes plastic deformation, and then cutting it from the outer surface side toward the back side while keeping the molding fixed and leaving a part of the part that was stretched and plastically deformed. How to cut the ends of synthetic resin molding.

(2) A device for cutting an elongated end portion of an elongated synthetic resin molding having an irregular cross section, including a fixed blade for fixing the molding;
A movable cutting blade provided opposite to the fixed blade, a blade portion formed on the cutting blade so as to cut the molding from the outer surface side to the back side, and a movable cutting blade provided opposite to the fixed blade; The cutting blade is formed on the cutting blade so as to come into contact with the molding and stretch it until the outer surface of the molding undergoes uniform plastic deformation, and has a shape corresponding to the outer surface of the molding, a predetermined wall thickness, and a radius. A device for cutting the ends of synthetic resin moldings, including a pressing part for deformation.

The present invention will be explained below with reference to embodiments shown in the drawings. FIG. 1 is a front view showing the cutting device, FIG. 2 is a front view showing a part of the cutting blade, FIG. 3 is a perspective view of the cutting blade, and FIGS. 4 to 6 are front views showing the cutting process. 7th
The figure is a front view showing the cut end of the molding, and FIG. 8 is a perspective view.

In the drawings, reference numeral 1 denotes a molding having an irregular cross section, which is formed into a long shape by extrusion molding, and is placed on a fixed blade 2. 3 is a movable cutting blade provided opposite to the fixed blade 2,
Blade portions 3a are formed on both sides of the intermediate portion of the plate-shaped body, and a plate-shaped pressing portion 3b is formed in a portion beyond the blade portion 3a. The pressing portion 3b has a suitable wall thickness a, and a radius b is formed at the corner of the tip, and the tip c has a shape corresponding to the top surface shape of the molding 1. Reference numeral 4 denotes a presser die that prevents the end of the molding 1 from bending during cutting, and is supported by a spring 5 so that it bends in accordance with the pressing force.

In the cutting device configured as described above, as shown in FIG.
When the molding 1 is placed on the molding 1 and the pressing portion 3b of the cutting blade 3 is pressed against it, the portion of the molding 1 to be cut is stretched and the outer surface undergoes uniform plastic deformation, as shown in FIG. In this case, the molding 1 is plastically deformed due to the correlation between the thickness of the pressing portion 3b, the pressing force, and the shear strength of the molding 1, and a radius d is formed. If the pressing is continued in this state, the blade part 3a reaches the upper surface of the molding 1, and the molding 1 is stretched between the molding part 3a and the fixed blade 2, leaving the part where the radius d is formed by stretching. The cutting 1 is cut from the outer surface side to the back side.

Molding 1 cut as above
As shown in FIGS. 7 and 8, the end of the holder has a radius d formed on the upper surface, followed by a cut surface e. Therefore, it is possible to produce moldings that are both dangerous and decorative.

In addition, in the above description, the stretching process and the cutting process may be performed in one operation, or may be performed in multiple operations. Further, the blade portion 3a and the radius b of the cutting blade 3 may be provided on one side or both sides, but if they are provided on both sides, the ends of both sides can be processed at the same time with one cutting. Furthermore, the blade part 3
a and the pressing portion 3b may be provided separately. Further, in the above embodiment, the cutting blade 3 is moved vertically, but it may be moved laterally or in other directions.

The present invention is applicable not only to side moldings and bumper moldings for automobiles, but also to other moldings for automobiles such as window moldings, and moldings for other uses such as furniture and building materials.

As described above, according to the present invention, since the molding is cut with the outer surface uniformly deformed plastically, it is possible to cut with a uniform radius formed on the outer surface of the end portion, which helps prevent danger. Decorative moldings can be produced. In addition, since the molding is fixed during cutting, there is no damage or deformation to the outer surface of the molding, and the outer surface of the molding is stretched until it undergoes plastic deformation before being cut. The appearance of the outer surface up to the cut surface can be maintained uniformly.

According to the cutting device of the present invention, the stretching and cutting of the molding can be performed in one continuous operation, so that the end treatment of the molding can be performed efficiently. In addition, since the pressing part has the same shape as the outer surface of the molding, it is possible to uniformly plastically deform the upper surface of the part of the molding to be cut, and since the molding is fixed and the cutting blade is movable,
No scratches or the like will occur on the outer surface of the molding. Furthermore, a press part for plastic deformation with a predetermined wall thickness and radius contacts the molding before the blade part, and after forming a continuous radius on the outer surface of the molding, it is cut to form a cut surface. Therefore, it can be formed continuously from the outer surface to the radius.

Furthermore, if the blades are provided on both sides, the ends of both sides can be cut in one operation, and the end of the molding can be processed more efficiently.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a cutting device according to an embodiment of the present invention, Fig. 2 is a front view showing a part of the cutting blade, Fig. 3 is a perspective view of the cutting blade, and Figs.
The figure is a front view showing the cutting process, FIG. 7 is a front view showing the cut molding, and FIG. 8 is a perspective view thereof. In each figure, the same reference numerals indicate the same or equivalent parts, 1 is a molding, 2 is a fixed blade, 3 is a cutting blade, 4 is a presser die, and 5 is a spring.

Claims (1)

[Scope of Claims] 1. A method for cutting an elongated end portion of an elongated synthetic resin molding having an irregular cross section, by pressing the portion of the molding to be cut from the outer surface side, After stretching until the outer surface undergoes uniform plastic deformation, cut from the outer surface to the back side while keeping the molding fixed and leaving part of the part that was stretched and plastically deformed. A method for cutting the ends of synthetic resin molding, characterized by: 2. The method for cutting ends of a synthetic resin molding according to claim 1, wherein the stretching step is performed until the outer surface of the molding forms a radius due to plastic deformation. 3. A device for cutting the long end portion of a long synthetic resin molding having an irregular cross section, including a fixed blade that fixes the molding, and a movable cutting blade provided opposite to the fixed blade. a blade, a blade portion formed on the cutting blade so as to cut the molding from the outer surface side to the back side; and a blade portion that contacts the molding before the blade portion so that the outer surface of the molding A molding made of synthetic resin, which is formed on the cutting blade so as to be stretched until uniform plastic deformation occurs, and includes a pressing part for plastic deformation having a shape corresponding to the outer surface of the molding, a predetermined wall thickness, and a radius. terminal disconnection device. 4. The device for cutting the end of a synthetic resin molding according to claim 3, wherein the blade portions are formed on both sides.