JPS5935836A - Knockout structure - Google Patents

Abstract

PURPOSE:To insert easily a tool for cutting a bridge, by forming a slit on the first face containing a corner part formed by crossing of two faces for constituting a substrate, surrounding a knockout part, opening the slit of the corner part like a section sector, and connecting the knockout part and the second face by the bridge by crossing the corner part. CONSTITUTION:The first bridge 7 is formed by crossing a slit 5, in a corner part 4, and also the second bridge 10 is formed by crossing other part of the slit 5, in the first face 2. By both these bridges 7, 10, a knockout part 6 is connected to the second face 3 and the first face 2. Subsequently, the slit 5 is opened like a section sector in the corner part 4, and other part is opened like a square so that the width becomes as narrow as possible.

Description

[Detailed description of the invention] [Technical field of invention] The present invention is a knockout structure (1) that facilitates punching work. Regarding construction.

[Technical background of the invention]

A conventional knockout structure is surrounded by a slit in one plane constituting the board and connected to the periphery by a bridge formed in a part of the slit, and the bridge is punched by cutting the bridge with a nipper using any tool. was.

[Problems with background technology]

Because the slit width had to be wide enough to allow the tool to be inserted, the strength of the bridge before piercing was insufficient.
It was also easy for trash to get in.

[Purpose of the invention]

To provide a knockout structure that is easy to punch through and has high mechanical strength before punching.

[Summary of the invention]

In a substrate formed by two intersecting surfaces, the first
The slit width is minimized and the bridge is surrounded by a slit that is formed on the surface and has a fan-shaped cross section at least at the corner, and is surrounded by a knockout section that is continuous on the second surface by a bridge provided at the corner. In addition, the tool for cutting the bridge can be easily inserted.

[Embodiments of the invention]

The details of the invention will be explained by means of illustrated embodiments.

FIG. 1 shows the state of this embodiment before reversibility. (1) is a synthetic resin substrate, (2) is a first plane constituting this substrate (1), (3) is a second plane that is almost orthogonal to this plane (2), and (4) is on these sides. The first part includes a corner part formed by intersecting planes (2) and (3), and (5) a corner part (4).
A rectangular annular slit formed in the plane (2), (6) is a rectangular knockout part surrounded by this slit (5),
(7) A knockout part (6) is formed at the edge part (4).
) and the second plane (3). As shown in the second figure, the slit (5) has a corner portion (4) opening in a fan-shaped cross section, and a first surface (2) opening in a rectangular shape as narrow as possible.

To make this knockout part (6) reversible, as shown in the second figure, the blade (8a) of a tool (8) such as nippers is aligned with the second plane (3) 1tll, and the cutting edge (8b) is cut into a slit ( 5) and cut the bridge (7). Then, as shown in Figures 3 and 4, K, bridge (7
) can be cut at its base and the knockout (6) removed to form the through hole (9).

However, in this embodiment, since the bridge (7) is provided at the corner (4), the cross section is fan-shaped as shown in FIG. 2, and the bottom of the slit (5) Even if the width is small, the cutting edge (8b) of the tool (8) can be inserted and cut. Moreover, the blade (8a) of the tool (8) is
If it is on the flat side, the remaining mark (7a) of the bridge (7) can be cut extremely short.

In this way, the knockout structure of this example has slits (5
) has a fan-shaped cross section, so even if the width is reduced, the bridge (7
) can be easily cut, and since the bridge (7) is short, the mechanical strength before reversibility is high, and since the width of the bridge (7) is narrow, there is little risk of dirt entering. Furthermore, since the bridge residual mark (7a) is short and its protruding direction is in the extending direction of the second plane (3), that is, the depth direction of the through hole (9), it is possible to insert an electric wire etc. There is no risk of damage.

(3) Next, another embodiment is shown in FIG. This forms a first bridge (7) across the slit (5) at the corner (4) and the first bridge (7). A second bridge 01 is formed across the other part of the slit (5) on the surface (2) of the knockout portion (6) by these bridges (7), (1, 1). ) and the peripheral portion of the first surface (2).Thus, the slit (5) is opened in a fan-shaped cross section at the corner portion (4), and the other portion is opened in a rectangular shape as narrow as possible. ing.

To make this thing reversible, first, cut the first bridge (7) with a tool in the same manner as in the previous embodiment, and then raise the knockout part (6) with your fingers to open the second bridge α1. Break it off.

In this way, this embodiment also has a corner part (4) of the slit (5).
Since the opening has a fan-shaped cross section, even if the bottom of the slit (5) is made narrow, it can be easily reversible using a tool.
It has the advantage of less intrusion of dirt, etc. Furthermore, since this example has two bridges, it is mechanically strong.

In addition, in each of the above-mentioned embodiments, there is only one slit (4) at the corner, but in the present invention, there may be any number of slits at the corner, and the cross-sectional shape of the slit other than the corner is free. .

Furthermore, the substrate of the present invention is not limited to being made of synthetic resin, but may be made of metal. Further, the two surfaces forming the corner portion may be a combination of curved surfaces or a combination of a curved surface and a flat surface.

〔Effect of the invention〕

In the knockout structure of the present invention, a slit is formed in a first surface including a corner portion formed by intersecting two surfaces constituting a substrate to surround the knockout portion, and the slit in the corner portion is opened to have a fan-shaped cross section. Moreover, since the knockout part and the second surface are connected by a bridge across the corner part, the bridge can be easily cut even if the width of the slit is made small.As a result, the strength before reversibility is high, Moreover, it is easily reversible, the bridge leaves little trace, and the protruding direction is in the depth direction of the through hole, so there is no risk of damaging electric wires, etc. Furthermore, the slit is small, so there is no risk of dirt entering. There is.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the knockout structure of the present invention before piercing, FIG. 2 is an enlarged cross-sectional view of the main part, FIG. 3 is an enlarged cross-sectional view of the main part after reversibility, and FIG. Also a perspective view, No. 5
The figure is a perspective view of another embodiment. (1)...Substrate (2)...First surface (3)
... Second surface (4) ... Corner part (5) ... Slit (6) ... Knockout part (7) ...
Bridge (7a)...Remains of bridge (9)
...Toukou 00...Second Bridge Agent
Patent Attorney Mr. Inoue (7) Figure 1 Figure 3 Figure 4 Figure a '4, 3 l Figure 5

Claims (2)

[Claims] (1) A substrate whose two surfaces intersect to form a corner, and a knockout portion formed on a first surface including the corner and at least a portion of the corner surrounded by a slit having a fan-shaped cross section. And at least in the above part.”
A knockout structure comprising: a bridge formed across the slit and connecting the knockout portion to a surrounding substrate portion. (2) A patent claim characterized by comprising a first bridge formed across a slit at a corner and a second bridge formed across the slit on a first surface other than the corner. The knockout structure according to item 1.