JPS5876343A - Manufacture of core for edge member - Google Patents

Abstract

PURPOSE:To prevent generation of cracks in side edges of a core, which is buried in an edge member to be mounted at the rigid edge of the opening of a car, by forming notches with a circular part at side edges of the coupling part. CONSTITUTION:A metal sheet 1 in the form of strip is provided with a number of slits 3 in the width direction to form many strip-shaped cores 2, in which non-slit parts 4, 4 are provided in the longitudinal direction of the metal sheet 1 for the purpose of coupling cores 2 with one another. Small holes 7 are punched at the border parts to each slit 3 on both sides of the non-slit part 4, and then the non-slit part 4 is rolled and stretched. Thereby a core gap is formed together with each coupling part 8 while a notch 9 with circular part is formed by small holes 7 at the side edge of the coupling part 8. A core 10 so made is covered with a covering 18 consisting of rubber etc., and then bent into a U shape in profile to serve as an edge member.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for manufacturing a core metal embedded in an edge member such as a trim or weather strip that is clamped onto a rigid edge of a panel flange or the like protruding from the periphery of an opening in an automobile. It is related to.

Conventionally, as shown in FIG. 1, a method of manufacturing a core metal for this type of edge member involves punching out a large number of through holes with a press and forming a large number of cores 2.
There is a method of forming a and its connecting part 8a to give flexibility to 1 m of a belt-shaped metal plate, but according to this method, the punched part with a core gap of d = 1.2 to 1.5 is discarded. However, the cost was high due to material loss.

Moreover, as shown in FIG. 2, the metal plate 1bK first has many cuts 1.
8 by press working in the width direction, and then the two non-slit portions 15 on the left and right along the longitudinal direction of the metal plate 1b are rolled with stretch rolls to widen the slit width in the same manner as shown in FIG. There is a method of forming the core 28 and the connecting portion 8a. In this method, the core gap d is
If the required amount is, for example, 1.2 to 1.6 fl, it is inevitable that the connecting portion 8a will become thin. Therefore, the 8th
As shown in the figure, when the core bar 16 is formed into a U-shaped cross section and is attached to a corner portion having a minimum radius of curvature (R = 40 to 6 ON), a clamp is attached to the side edge 17 of the connecting portion 8a. x: Easy to enter, and stress is concentrated in this part, making it easy to break. In particular, products with so-called one-sided connections, in which one of the left and right connections is cut off in order to provide flexibility in the tertiary direction, have a disadvantage in that their product lifespans are extremely short.

This invention has been made in order to eliminate the drawbacks of the conventional method of manufacturing a core metal of an edge member as described above.

Manufacture of core metal of this invention based on Figure 9 An example of the method will be described.

First, in order to form a large number of strip-shaped cores 2 in a thin strip-shaped metal plate 1, a large number of slits 3 are formed in the width direction by press working. At this time, two non-slit portions 4, 4 on the left and right sides are provided along the longitudinal direction of the metal plate 1 in order to connect the cores 2 to each other.

At the same time, one small hole 7 is punched at the boundary between each slit 8 on both sides of the non-slit portion 40.

Thereafter, the two non-slit portions 4 on the left and right sides are rolled by stretch rolls, and as a result, as shown in FIG.
A notch 9 is formed on the side edge of the connecting portion 8, and a notch 9 is formed by the small hole 7.

The strip-shaped core metal 10 thus produced is coated with chloride and Yale resin or rubber 18 as shown in Figure 9, and then bent into a U-shaped cross section to form an edge member.

Even when the edge member is foamed at a part of the corner where it has a minimum radius of curvature (R = 40 to 60 m), the core metal 1-0 is formed on the side line of the connecting portion 8 as shown in FIG. Due to the existence of the highly arcuate notch 9, it can be curved without any force, and stress will not be concentrated on the connecting portion 80 side and cracks will not occur as in the conventional case.

In addition, as mentioned above, the core gap d of the core metal lO is set to 1.2 to 1.
．． 5H, the thickness of the connecting portion 8 due to rolling is 0.5H.
When the edge member is attached to the rigid edge F as shown in Fig. 9, the reaction force R of the gripping force is applied to the point of application A, but the bending moment generated by this is We will examine whether or not the strength and gripping force of the connecting portion 8, which has a reduced plate thickness, decreases.

That is, considering the leg portion 11 of the core bar 10 as a cantilever beam with the base end B as the fixed end, the distance χ from the point of application A of the reaction force R to the connecting portion 8 is χ, where e is the distance between AH. = Monthly e-V4g.

In addition, the leg part 11, which is a cantilever beam, has a constant width (b) and the thickness of the plate gradually increases from the point of action A to the base end B.The leg part 11 is a so-called equal strength beam in which the stress is uniform where the plate thickness gradually increases from the point of action A to the base end B. Assuming that the plate thickness (F) of the connecting portion 8 at a distance χ is proportional to the square root of the distance χ from the formula v=,8 and y. Therefore, if the thickness of the base end B of the leg portion 11 is h, the thickness of the base end B of the rolled portion (h)
Therefore, the above-mentioned - calculated plate thickness of connecting part 8)
It's almost the same as that.

Therefore, the grip and strength of the edge member relative to the rigid edge F will not deteriorate even if the plate thickness of the connecting portion 8 becomes thinner due to rolling. FIG. 10 illustrates another embodiment of the present invention, in which left and right connecting portions 5.6 are formed between each core 2 as shown in FIG. A lateral gap 12 due to shearing is provided only in one of the connecting portions 6, for example, to increase the three-dimensional flexibility of the edge member.

As described above, according to the present invention, when the core metal 10 is used as an edge member, since the arcuate notch 9 is formed in the @green part of the connecting portion 8, the edge member has a minimum radius of curvature (R = 40 to 60 fi).
Even if it is attached to a part of a corner where the connecting portion 8 is attached, it will curve without difficulty, and there will be no stress concentration on the side line of the connecting portion 8 and generation of cracks as in the conventional case.

In addition, 11Jd=1.2 between many cores on a strip-shaped metal plate
Unlike the method of punching ~1.5 fl, this method has the advantage that there is no loss of material and is advantageous in terms of cost.

[Brief explanation of drawings]

Figure 1 is a plan view of a core metal made by a conventional manufacturing method.
Fig. 2 is a plan view of a cored bar made by another conventional manufacturing method before rolling, Fig. 8 is a front view of a cored bar made by the manufacturing method of Fig. 2, and Fig. 4 is a 9 is a view taken along arrow N-IV in FIG. 8. FIG. Figures 5 to 8 show the manufacturing process of the core metal of the edge member according to the present invention, Figure 5 is a plan view of the metal plate after processing such as slits, and Figure 6 is the metal plate. Fig. 7 is a front view of a metal core formed by bending a metal plate into a U-shaped cross section;
It is a view taken along the ■-■ arrow in the figure. FIG. 9 is an explanatory diagram for calculating the gripping force of the core metal when used as an edge member, and FIG. 10 is a plan view of a metal plate showing another embodiment of the present invention. 1 Metal plate 2 Core 8 Slit 4 Non-slit portion 5.6 Connecting part 7 Small hole 8 Connecting part 9 Notch 10 Core bar 12 Gap F Rigid edge patent Exit door Person Torikawa Rubber Industries Co., Ltd. Attorney, Patent attorney, - Old 1) Tsuyoshi size 30 La 7 Prisoner 0

Claims (1)

[Scope of Claims] 1. In a method for manufacturing a core metal to be embedded in an edge member such as a trim having a U-shaped cross section and attached to a rigid edge, a large number of strip-shaped cores' are formed in a band-shaped metal plate. In order to connect the cores, when creating a large number of slits in the width direction by press working, two slits are made on the left and right along the longitudinal direction of the metal plate to connect the cores.
A non-slit portion of the strip is provided, and a small hole is punched at the boundary between the non-slit portion and the slit on both sides. Next, the non-slit portion of the two left and right strips is rolled with a stretch roll, and the non-slit portion is stretched to form a connecting portion. 1. A method for manufacturing a core metal for an edge member, characterized in that a core gap is formed at the same time as a core gap, and a curved notch is formed at a side edge of a connecting portion. 2. Shikin manufacturing of the edge member according to claim 1, characterized in that a lateral gap is provided by shearing only in one of the two connecting portions on the left and right along the longitudinal direction of the metal plate. Method.