JPH0270345A - Manufacture of nail - Google Patents

Abstract

PURPOSE:To finish a product with high accuracy by forming an inverted cone- like pointed part in the lower end of a drum part simultaneously at the time of bringing a screw groove to form rolling to the outside peripheral surface of the drum part by a pair of dies and forming equally the right and the left rise angles of its pointed part. CONSTITUTION:By bringing a round bar-like stock 6 to forged working, a head part 3 and a drum part 2 are formed, and thereafter, at the time of bringing a screw groove 5 to form rolling to the outside peripheral surface of the drum part 2 by a pair of dies 11, 12, an inverted cone-like pointed part 4 is formed simultaneously. As a result, the drum part 2 of roundness can be formed easily, and also, by forming the pointed part 4 by rolling centering around an axis center of the drum part 2, the right and the left rise angles theta1, theta2 of its pointed part 4 can be formed equally.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a nail having a lower end of the body forming a head at the upper end thereof having an inverted conical shape, and a screw groove formed on the outer peripheral surface of the lower side of the body. Regarding the manufacturing method.

"Prior Art" Conventionally, in the above nails, the needle body was formed by a nail making machine, and the thread groove was formed by rolling.

``Problems to be Solved by the Invention'' However, the needle body formed using a nail making machine has a large clamping force applied to the material from the left and right or top and bottom, and the cross section of the body becomes oval. Since the cutter is used to cut from the left and right or from the top and bottom into a conical shape, the deformation of the body and the timing shift of the cutter overlap, making it impossible to obtain the same rising angle of the apex on the left and right sides. There were problems with accuracy that led to bending.

"Means for Solving the Problems" However, the present invention involves forging a round bar-shaped material to form a head and a body, and then rolling thread grooves on the outer peripheral surface of the body using a pair of dies. At the same time, an inverted conical tip was formed at the lower end of the body.

"Function" Therefore, according to the present invention, it is possible to easily form a perfectly circular body, and by forming the apex by shifting around the axial center of the body, the left and right rising angles of the apex can be easily formed. This makes it possible to form the parts equally, and to finish the product with higher precision than in the past.

"Example" Examples of the present invention will be described below in detail based on the drawings. Figure 1 is an explanatory diagram of the manufacturing process, and Figure 2 is an overall view of the product. In Figure 1, +11 is a pachinko nail, which has a round bar shape. A head (3) with a spherical upper surface is formed at the upper end of the body (2), and an inverted conical tip (4) is formed at the lower end, and a screw is formed on the lower outer peripheral surface of the body (2). A groove (5) is formed.

When manufacturing the above-mentioned pachinko nail (1), first of all, as shown in Fig. 1 (
As shown in Al tBl, a round bar-shaped material (6) made by cutting a brass wire into a predetermined length is placed in the first swaging die (7).
) and punch (8), second swaging die (9) and punch (lO), swaging in two steps, as shown in Fig. 1 [
As shown in C1, the diameter of the body (2) of the product and the shape of the head (7) are given to one end of the material (6).

Thereafter, as shown in FIG. The other die (12) is moved back and forth in the longitudinal direction, and each die (111 (121) is used to roll up the shaft of the material (6) (rolling), as shown in FIGS. 3 and 4. The opposing surface of each die + Ill (121, that is, the rolling surface (llal) has a thread groove forming mountain part (13) inclined and continuously formed with a constant width in the longitudinal direction, and the thread groove forming part (13) is formed continuously with a constant width in the rolling direction. is enlarged downward, and the interval between each die + ill (121) is sequentially narrowed, and the inclined cutting surface (14) that eliminates the interval at the position (P) before the end of the sideburn is fixed at the lower side of the mountain part (13). It is formed through a wide groove (15).

As a result, the thread groove (5) of the product is rolled in several rotations after the crest (13) bites into the outer peripheral surface of the lower side of the shaft of the material (6), and the shaft of the material (6) is rolled. is the die (Ill
(12) When the distance (Ll) from being supplied to the position (P) is transferred around its axis, the lower end of the axis of the material (6) is shaped like an inverted cone due to the inclined cutting surface (14). The material (6) is given an inverted conical tip (4) shape whose left and right rising angles (θ, ) (C2) are equal to the length of the body (2) of the product. Nail (2)
is manufactured.

Note that there is a tip (4) between the thread groove (5) and the tip (4).
) There is a gap (16) that is the return allowance for the meat during formation.

"Effects of the Invention" As is clear from the above embodiments, the present invention forges a round bar-shaped material (6) to form a head (3) and a body (2), and then a pair of dies (ill). (When rolling the thread groove (5) on the outer peripheral surface of the body (2) by 121, an inverted conical tip (4) is formed at the lower end of the body (2) at the same time. The left and right rising angles (θ,
(θ snow) can be formed equally, compared to conventional products (
Since 1) can be finished with high precision, it has a remarkable effect that pachinko nails (1) can be properly driven into pachinko machines.

[Brief explanation of the drawing]

Fig. 1 is a manufacturing process explanatory diagram showing one embodiment of the present invention;
The figure is an overall view of the product, FIG. 3 is a front view of the die, and FIG. 4 is a sectional view thereof. (11... Pachinko (product) 2... 3... 4... 5... 6...

Claims (1)

[Claims] After forging a round bar-shaped material to form a head and a body, when rolling a thread groove on the outer peripheral surface of the body using a pair of dies, at the same time an inverted conical tip is formed at the bottom end of the body. A method for manufacturing nails characterized by: