JPS5929125Y2 - Threaded portion of the tapping screw in the panel - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a threaded portion of a tapping screw in, for example, a back panel of an automobile door.

This type of panel usually has a double structure in which the outer panel and the inner panel are overlapped, and in order to attach the outer panel to the inner panel, a screw hole 3.4 is conventionally provided in the outer panel 1 and the inner panel 2. Inner plate 2
A tapered portion 2A is formed on the periphery of the screw hole 4 by burring process, and the screw hole 3, 4 is
By screwing the tapping screw 5 through the washer 6.

However, in the above-mentioned conventional configuration, when the tightening torque of the tapping screw 5 becomes excessive, the axial force of the tapping screw 5 causes two portions of the taper of the inner plate 2 to swell upward as shown by the dotted line in FIG. However, the screw hole 4 becomes a blank hole and the tightening force of the tapping screw 5 is greatly reduced, and a spring washer or plate is used to prevent the tapping screw 5 from returning and ensure fastening. It has drawbacks such as the need for a washer of type 6 such as a washer.

The purpose of the present invention is to improve the above-mentioned drawbacks of the prior art and firmly screw a tapping screw into a panel. In this configuration, the lower surface of the tapping screw head is tapered, the outer plate's screw hole periphery is formed with a tapered part shaped to be in close contact with the tapered head lower surface, and the white plate's screw hole periphery is A taper part is formed that is slightly deeper than the taper part of the outer plate, and the taper part of the outer plate and the taper part of the inner plate are in close contact with each other at the upper edge and at the periphery of the screw hole at the lower edge. The main idea is to make a slight gap appear.

The present invention will be explained with reference to an embodiment shown in the drawings.
, screw holes 13 and 14 are provided in the inner plate 12, respectively, and the lower part of the head 5A of the tapping screw 5 to be screwed into the screw holes 13 and 14 has a tapered shape.

A tapered portion 11A having a shape to be in close contact with the lower surface 5B of the head 5A of the tapping screw 5 is formed on the peripheral edge of the screw hole 13 of the outer plate 11 by burring, and a tapered portion 11A of the screw hole 14 of the inner plate 12 is shaped by burring. The tapered part 11A is on the periphery.
A slightly deeper taper portion 12A is formed, and thus the taper portion 11A of the outer plate 11 and the taper portion 12 of the inner plate 12 are formed.
A means that a slight gap 15 is formed at the periphery of the screw hole 13,14.

In the above configuration, when the tapping screw 5 is screwed, the taper portion 11A of the outer plate 11 is connected to the tapping screw 5.
The axial force of the tapping screw 5, which is pressed downward by the lower surface of the head 5A, and whose tightening is based on torque, bulges the tapered portion 12A of the inner plate 12 upward, and the tapered portion 1
Due to the elastic deformation of 2A, the tapping screw 5 is prevented from returning and fastening is performed reliably.

Then, as shown in FIG. 3, a tapered portion 12A of the inner plate 12
When the upper surface fully contacts the lower surface of the tapered portion 11A of the outer plate 11, the pressing force exerted on the tapered portion 11A of the outer plate 11 and the rising force of the tapered portion 12A of the inner plate 12 are balanced against each other, and the outer plate 11 is brought into contact with the lower surface of the tapered portion 11A. Tapered part 11A of plate 11 and inner plate 12 taper part 12
Due to the mutual reinforcing effect with A, it will no longer deform.

Thus, the screw hole 13 of the outer plate 11 and the inner plate 12
Both screw holes 14 are prevented from becoming blank holes.

As mentioned above, the present invention is attributable to the axial force based on the tightening torque of the tapping screw in a part of the taper formed around the periphery of the screw hole in the outer plate and a part of the taper formed around the periphery of the screw hole in the inner plate. The direction of deformation is opposite, and furthermore, the tapered part of the outer plate and the tapered part of the inner plate are in close contact at the upper edge, and there is a slight gap around the periphery of the screw hole at the lower edge, so that both are completely flat. When it comes into close contact with the body, both of them compete with each other to limit the wide deformation of the periphery of the screw hole, and as a result, even if the tapping screw is strongly tightened, the screw hole is prevented from becoming a blank hole.

Furthermore, the tapered part 6 of the inner plate is slightly elastically deformed based on the slight gap at the periphery of the screw hole between the tapered part of the outer plate and the tapered part of the inner plate, and the elastic force due to the deformation is generated. This prevents the tapping screw from returning and enables reliable fastening without using a washer.

Furthermore, when the outer plate and the inner plate are superimposed, a tapered portion of the outer plate fits into a tapered portion of the inner plate, making positioning of the outer plate and inner plate extremely easy.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of a panel being tightened by a conventional tapping screw; Fig. 2 is a side sectional view of an embodiment of the present invention; Fig. 3 is a side sectional view of a panel being tightened by a tapping screw; Figure 2 is a side cross-sectional view showing the state of close contact between the outer plate and the inner plate after tightening. In the figure, 1, 11... Outer plate, 2, 12...
・Inner plate, 3.4, 13, 14... One screw hole, 5... Tapping screw, 11A, 12
A: Part of the taper, 15: Gap.

Claims (1)

[Scope of utility model registration request] In a configuration in which a tapping screw is screwed into a screw hole in a panel consisting of an outer plate and a white plate, the lower surface of the tapping screw head is tapered, and the periphery of the screw hole in the outer plate is provided with a taper-shaped lower surface of the head. A tapered part with a shape that should fit tightly is formed, and a taper part slightly deeper than the taper part of the outer plate is formed around the screw hole of the inner plate, so that the taper part of the outer plate and the taper of the inner plate are formed. A threaded portion of a tapping screw in a panel, characterized in that the upper edge of the panel is in close contact with the upper edge and a slight gap is formed around the periphery of the screw hole in the lower edge.