JPS6061143A - Production of nut - Google Patents

Abstract

PURPOSE:To make efficiently mass production of a nut having arc-shape notched curved surfaces in the opposed positions of screw threads at a low cost by manufacturing a core by segmental dies of which both ends of the projecting line forming grooves are formed to notch recesses having an arc shape and using said core. CONSTITUTION:The positions of segmental dies 6a, 6b for forming grooves 7 of a core 4 where projecting lines 8 thereof face each other are formed to notch recesses 10 having an arc shape. The draft of the lines 8 with respect to the dies 6a, 6b is thus prevented by the recesses 10 from inverting and the easy mass production of the core 4 is made possible. The efficient mass production of a nut 1 at a low cost is made possible by using a casting mold 5 formed by combining the core 4 and a master mold 2 manufactured by a high speed molding machine, etc.

Description

[Detailed Description of the Invention] The present invention provides a cast nut at a low cost.
Manufacturing method; two related matters.

Conventionally, when producing relatively large special nuts, methods such as cutting female threads on hexagonal steel bars or forging them have been used, but the former method wastes a lot of material and is time-consuming. The latter method had drawbacks such as the risk of cracking during deformation unless carefully selected materials were used.

The present invention aims to overcome these drawbacks by slightly changing the shape of the core. The structure of the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

The nut (1) is made using a mold (5) that combines an outer mold (2) for shaping the outer shape of the nut (1) and a core (4) for shaping the internal thread (3) of the nut (1). In the nut manufacturing method ζ2, which involves casting the core (4), M M (ea)
(6b) When forming two twists, the thread groove (
The split mold (6a)ωb) of the protrusion (8) that forms the sword (
6! I) Both ends of (6b) approaching the mating surface (9) are formed into arcuate notch recesses aQ.

This notch recess Qω is at least m-shaped ωa) (6b)
It is necessary to form the shape C2 of a size that eliminates the portion where the draft angle of the protrusion (8) is opposite to the ridge.

In Example 12, the outer mold (2) uses foundry sand and is molded using a high-speed molding machine.

In addition, type III (aa) (ab) uses metal or wooden molds.

A core (4) is manufactured using this IIJm (6ω et al. 0).

In non-example examples, coachite sand or blended sand having thermosetting or gas-curing properties is used as the core sand.

By using this core (4), a two-twist nut (opposite positions of the screw threads aυ of 11) (two arcuate notched curved surfaces ←3 are formed).

The "opposing position" here refers to a position every half circumference of the screw thread (Iυ).

In this example, the nut (4
), but other metals may of course be used.

In the figure, 0 indicates the peeling of the core (4), and 141 indicates the positioning protrusion.

(IF5) Mahabaki (seat 19, αe is the dowel hole into which the positioning protrusion I is fitted, αD is the convex part molded on the core (4) corresponding to the notch recess u (It2), the bet is the hot water Road, (liJ
is a boiling bath.

The present invention is a nut manufacturing method in which a nut (1) is cast using a mold (5) which is a combination of an outer mold (2) and a core (4) as described above! - Place the core (4) in the split mold (ea) (ab
), the protrusions (8) of the split molds (6a) (6b) forming the thread grooves (7) of the core (4) are
(6a) The mating surfaces (9) (-) of (6b) are formed into arc-shaped notched recesses at both ends, so the split mold (6a)
The part where the draft angle of the protrusion (8) with respect to (6b) is supposed to be the opposite slope is eliminated by this notch recess (Ill2), and the split mold (oa) (ab) can be easily pulled out, so that the internal thread part (3 ) In order to mold (two necessary cores (4) are extremely easy to produce; two cores (4) are required).

In addition, since the outer mold (2) can be easily manufactured using a high-speed molding machine, the outer mold (2) and the core (4
) can be easily produced, and since this mold (5) is used to cast (1), a cast nut (
1) can be produced efficiently at low cost (2).

In addition, in this manufacturing method (oak manufactured from 2), the opposing position of the thread αυ of tlJ is the split mold C6E1) (6b
) is formed with an arcuate notch curved surface corresponding to the four notches, so the frictional resistance during screwing is reduced accordingly, making it easier to use.

As described above, the present invention provides an innovative method for manufacturing nuts that can supply cast nuts in large quantities (low cost).

[Brief explanation of drawings]

Fig. 1 is a perspective view of the Ilj grip, Fig. 2 is a plan view of the core, Fig. 3 is a side view thereof, Fig. 4 is a sectional view thereof, Fig. 5 is a sectional view of the mold, and Fig. 6 is a nut. FIG. (1) Nut, (2) Outer mold, (3) End/female thread, (4) Core, (5) Mold, (6a) (6
b)...IIJ type, (7). ψ thread groove, (8)...projection, (9)...mating surface, (1(
1...Large cutout recess, aυ...screw thread, circle...circular notch curved surface. September 14, 1981 Applicant: Katagai Seisakusho Co., Ltd. Inventor: Souji Amano (7) =229- ″7%7% Gummy 'Jn-

Claims (1)

[Claims] In the nut manufacturing method, nuts are cast using a mold that combines an outer mold that shapes the outer shape of the nut and a core that molds the internal thread of the nut. Both ends of the protrusion of the split mold that forms the thread groove that approach the mating surface of the split mold are formed into arc-shaped notched recesses, and this split mold is used to manufacture a core, and this core is used. A method for producing a nut, characterized in that an arcuate notch curved surface is formed at a position opposite the thread of the nut.