JPS5950456B2 - How to form the screw head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming a ratchet head of a screw which is adapted to be fixed to an object by rotational action.

Generally, the rotation of the screw described above is performed by inserting the tip of the screwdriver into a groove formed on the top surface of the screw head, but the screwdriver may slip out of the groove during rotation and damage surrounding equipment. In order to prevent this, it is necessary to provide a rim around the head of the screw.

Conventionally, the method for providing the edge is to drive a hollow cylindrical collar around the cylindrical screw head in which the driver insertion groove is formed, to prevent the driver from coming off from the groove due to the presence of the force. I've been trying to prevent it.

However, in order to prevent the collar from coming off after being driven into the screw head, it is necessary to narrow the dimensional tolerance range between the inside diameter of the collar and the outside diameter of the screw head. The thickness of the plating applied to the collar and head of the screw must also be considered.

Therefore, under such severe conditions, the yield rate of products tends to be low.

In addition, the driver insertion groove on the top surface of the screw head is formed by milling, but this milling process is more complicated than other processing methods such as drilling, and the groove is not completed. It takes a considerable amount of time to complete the process.

Furthermore, the collar must be formed separately from the slicing head, which increases the number of steps.

The present invention eliminates the above drawbacks, improves the production efficiency of the screw head, shortens the production time, and simplifies the production process. In a method for forming a screw head in which a rim is provided around the screw head to prevent the driver from coming off the groove when the driver is rotated, first, a rim is provided around the screw head in a radial direction from a side surface of the screw head. This is achieved by a method of forming a slat head, characterized in that at least one hole is drilled and then a recess is formed on the top surface of the sew head so that the hole remains as the groove.

The present invention will now be explained by way of examples with reference to the accompanying drawings.

First, as shown by arrow A in FIG. 1a, a hole 13 is penetrated from the side surface 12 of the cylindrical screw head 10 in a direction perpendicular to the axis l, that is, in the radial direction of the screw head using a drill press. .

The through hole 13 is formed at a height H from the top surface 11 (FIG. 1b), and the height H is such that the driver 15 is in the groove 13A.
It is approximately equal to the height h (Figs. 2 and 3) of the edge 14 to prevent it from coming off.

The diameter of the through hole 13 is approximately equal to the width W of the wedge-shaped optical end of the driver 15 (FIG. 3a).

Next, as shown by the arrow B in FIG. 2a, the screw head 10 is
A recess 16 is formed by hollowing out.

As a result, the edge 14 is formed integrally with the slicing head 10.

The height of the edge 14, that is, the depth of the recess 16 is h, and the value of h is the depth d when hollowed out from above the top surface 11.
This is determined taking into consideration that the driver insertion groove 13A is formed and that the driver 15 does not come off the groove 13A and exceed the edge 14.

Further, the value of the diameter DR of the recess 16 is determined in consideration of the length U of the tip of the driver (FIGS. 2b and 3b).

Further, the depth d of the groove 13A is conveniently set by the driver 15.
Determine its value to match A.

According to the method for manufacturing the screw head according to the present invention, the edge for preventing the driver from coming off the groove is formed integrally with the screw head, so that the dimensional tolerance range is within the range as described at the beginning. The screw heads can be mass-produced without being bothered by the problem of narrowness, improving production efficiency.

In addition, the driver insertion groove is formed using a drill press and lathe, which are extremely easy to operate, so production time is shortened, and the rim and screw head are formed as one unit instead of separate, simplifying the production process. .

In addition, when forming a groove for a Phillips screw, two holes 1
3 in the radial direction of the screw head so as to be orthogonal to each other.

Furthermore, the method of the present invention can be applied to all commercially available screw heads that are not provided with edges or grooves.

[Brief explanation of the drawing]

FIG. 1 shows the first step in the method for manufacturing a horse head according to the present invention.
FIG. 2 is a perspective view and a top view of the ratchet head manufactured by the second step and the second step in the manufacturing method of the present invention. 3 are a front sectional view and a side sectional view showing a screwdriver inserted into the groove of a screw head manufactured by the method of the present invention. 10...Screw head, 11...Top surface of screw head, 12...Side surface of screw head, 13...
...Through hole, 13A...Driver insertion groove, 1
4... Edge, 15... Driver, 16.
・・・・・・Concavity.

Claims (1)

[Claims] 1. In a method for forming a screw head in which a rim is provided around a screw head in which a groove into which the tip of the screwdriver fits is formed so that the screwdriver does not come off from the groove when the screwdriver is rotated, first the above-mentioned At least one hole is bored in the radial direction from the side surface of the screw head, and then a recess is formed on the top surface of the screw head so that the hole remains as the groove. How to form the head.