JPH0849716A - Resin nut - Google Patents

Abstract

PURPOSE:To provide an inexpensive resin nut that has a locking function and does not damage a work. CONSTITUTION:A nut part 1 provided with a tool engagement part 2 on its outer circumferential face is formed from a resin material and the resin nut 1 is provided with a screwless hole 5 whose inside diameter is smaller than the outside diameter of the thread of a screw to threadly inserted in the center of the nut part 1 and larger than the root diameter. The screwless hole of resin material is thus smaller than the screw outside diameter so that thread is formed in this screwless hole by a screw or a bolt in fastening and loosening of the screw can be prevented by receiving elastic restitutive force from the outside face of the resin caused by elasticity of the resin material. Because the nut 1 is made of resin, it can lighten a work assembled thereby, improve assemble workability, reduce cost, and prevent a lens, a resin board, an exterior material, etc., from being damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut to be screwed into a screw thread, and more particularly to a resin nut used for fixing a lens of eyeglasses to a frame or the like.

[0002]

2. Description of the Related Art Generally, when fixing a lens to a metal member or the like in a frameless frame type eyeglass, after a T-shaped washer 31 made of a soft material is fitted from both sides into a mounting hole 22 of the lens 21 as shown in FIG. Usually, it is assembled to the metal member 24 using machine screws 25 and nuts 32. Further, other than glasses, for example, when fixing a work or connecting a work to each other, a screw is passed through a mounting hole of the work, and a nut is screwed into the thread of this screw. It is common.

[0003]

However, this conventional structure has a drawback that the nut is loosened during use because it does not have a loosening preventing function because it is tightened by a normal metal nut. In order to prevent this loosening, it is sufficient to tighten with a double nut, but this is unaesthetic. Further, in this structure, in the spectacles, the T-shaped washer is fitted from both sides of the lens in order to prevent the lens from being damaged, resulting in an increase in the number of parts and inferior workability in assembling, resulting in high cost. Also, for example, when fixing a resin plate or a decorative exterior material other than the lens with a screw and a nut, if the nut is metal, it will rust, or the nut will scratch the resin plate or the exterior material. There were problems such as attaching and loosening. The present invention is intended to solve these problems and to provide an inexpensive nut that has a locking function and does not damage the lens, the resin plate, or the exterior material.

[0004]

In order to achieve this object, a nut portion having a tool engaging portion on its outer peripheral surface is molded from a resin material, and a thread of a screw thread to be screwed into the center of the nut portion is formed. It is a resin nut in which an unthreaded hole having an inner diameter smaller than the outer diameter and larger than the root diameter is formed.

[0005]

In the resin nut of this structure, the threaded hole of the resin material is smaller than the outer diameter of the screw, so the thread is formed by the machine screw (or tapping screw) when tightening.
Moreover, the elasticity of the resin material can tighten the outer surface of the screw to prevent the screw from loosening. Further, since the conventional T-shaped washer is not necessary and the nut is molded with the resin material, the weight of the assembled product can be reduced.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, A is a resin nut, and a nut portion 1 having a tool engaging portion 2 having a hexagonal outer periphery,
The nut portion 1 and the bushing portion 4 extend concentrically from the tightening surface 3 of the nut portion 1.
Is integrally molded with a resin material (polyacetal resin, polyamide resin, or the like). This nut part 1
In the center of the hole, there is a hole 5 that has the same hole diameter over the entire length, and the hole diameter of this screw hole 5 is smaller than the outer diameter of the thread of the machine screw or tapping screw used as the mating screw. More specifically, it is formed in the same size as the effective diameter (or may be slightly smaller than the effective diameter). On the other hand, the inner diameter 6 of the bushing portion 4 is formed to be slightly larger than the outer diameter of the screw used, and the outer diameter of the bushing portion 4 is made smaller than the outer dimension of the nut portion 1 to form the tightening surface 3. Has been done. Further, the tool engaging portion 2 is a hexagonal shape in the embodiment, but may be a two-sided surface or another polygonal shape capable of engaging with a tool to be held. The resin nut A can be manufactured inexpensively by an injection molding method using various resin materials.

The resin nut A having this structure is most suitable for fixing the lens of the frameless glasses. As shown in FIG. 3, the bushing portion 4 of the resin nut A is inserted into the mounting hole 22 of the lens 21 to hold the tool engaging portion 2 (hexagonal outer shape portion), and the flat washer 23 and the metal member 24 (for example, frame metal fittings). ) And a metal machine screw 25 (or a tapping screw) which is inserted into the bushing portion 4 are further pushed into the inner diameter 6 of the bushing portion 4, and when the machine screw 25 is screwed in from this position, the machine screw 2
5 abuts on the unthreaded hole 5 and is screwed in while forming a screw thread by the machine screw 25. This resin material is made of polyacetal resin or polyamide resin. Since the screwless hole 5 has almost the same diameter as the effective diameter of the screw 25, it can be easily screwed in. Moreover, the machine screw 25 is made of the elastic material of the resin material. The small screw 25 is tightened by the force, and the loosening of the screw can be prevented. A tapping screw may be used as the small screw 25, and in the case of a tapping screw, it is preferable that the hole 5 without a screw has a diameter slightly smaller than the effective diameter.

Next, another embodiment is shown in FIGS. The resin nut B shown in FIGS. 4 and 5 has a shape in which the bushing portion 4 of the resin nut A described above is removed, and other configurations are the same. That is, it is used when the bushing portion 4 is unnecessary, and the operation and effect of screwing and loosening prevention are the same as those of the resin nut A.

The resin nuts A and B are used in these embodiments.
However, the invention is not limited to this, and it can be used as a nut for attaching a work piece to a stud bolt instead of a machine screw, in addition to the eyeglasses. Instead, it can be used for various applications other than eyeglasses.

[0010]

As is apparent from the above description, the present invention is
A nut part with a tool engaging part on the outer peripheral surface is molded with a resin material, and a screwless hole with an inner diameter smaller than the outer diameter of the screw thread of the screw screwed into the center of the nut part and larger than the root diameter is formed. It is a resin nut. According to this invention, since the unthreaded hole of the resin material is smaller than the outer diameter of the screw, a thread is formed in this unthreaded hole by a screw thread such as a machine screw (or tapping screw) or a bolt when tightening. Due to the elasticity of the material, it is possible to prevent the screw from loosening by receiving elastic force from the outer surface of the screw. Further, since the nut is made of resin, it is possible to reduce the weight of the assembled work, the workability of the assembling is good, the assembling cost can be reduced, and the lens resin plate and the exterior material are prevented from being damaged. Furthermore, if the hexagonal shape of the resin member is made the same as the size of the metal nut, many effects can be obtained, such as the conventional tool can be used as it is.

[Brief description of drawings]

FIG. 1 is a partially sectional front view of a resin nut A of the present invention.

FIG. 2 is a bottom view of FIG.

FIG. 3 is an explanatory view showing a tightened state using a resin nut A.

FIG. 4 is a partial sectional front view showing a resin nut B of another embodiment.

FIG. 5 is a bottom view of FIG.

FIG. 6 is an explanatory view showing a conventional tightened state.

[Explanation of symbols]

 1 Nut part 2 Tool engagement part 3 Tightening surface 4 Bushing part 5 Screwless hole 6 Inner diameter A Resin nut B Resin nut

Claims (1)

[Claims] 1. A screw having an inner diameter smaller than the screw thread outer diameter and larger than the root diameter of a screw screwed into the center of the nut portion by molding a nut portion provided with a tool engaging portion on the outer peripheral surface with a resin material. A resin nut characterized by having a hollow hole.