JPH10176708A - Locking nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost nut having a locking function and preventing the damage of a lens. SOLUTION: A locking nut comprises a given female screw 2 formed; and a screwless hole 4 consisting of a screw-in part 4a having diameter equal to or lower than the effective diameter of a female screw 2 and a vertical groove part 4b more escaping to the outside than the screw-in part 4a formed on the central line of the female screw and is formed of a resin member 3. Thereby, since, during fastening, the locking nut is formed of a resin member, an elastic force is provided and an axial fastening strength is sufficiently ensured. Besides, since the screwless hole of the resin member has diameter lower than the outside diameter of a screw, during fastening, a thread is formed by the screw itself, and the outer surface of the screw is fastened by the elastic force of the resin member to prevent unfastening of the screw. Further, since a need for a T-type washer is eliminated by an integrally molded bushing part 5, assembly workability is improved, an assembly cost is reduced, and the damage of a lens is also prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking nut which is optimal for a small, low-load tightening portion, for example, for fixing an eyeglass lens to a frame.

[0002]

2. Description of the Related Art For example, when a lens is fixed to a metal member in frameless frame-type glasses, a T-shaped washer 31 made of a soft material is fitted into a mounting hole 22 of a lens 21 from both sides as shown in FIG. , Is usually assembled to the metal member 24 using a small screw 25 and a nut 32.

[0003]

However, this conventional fixing method is a method of tightening with a normal metal nut, and has a drawback that the nut does not have a locking function and the nut is loosened during use. In order to prevent this loosening, it is sufficient to tighten with a double nut or to perform a work to prevent loosening after tightening, but the appearance is bad and the cost is high. Further, in this fixing method, in order to prevent the lens from being damaged, T-shaped washers are fitted from both sides of the lens, so that the number of parts is increased, the workability of assembling is poor, and the cost is increased.

An object of the present invention is to solve these problems,
It is an object of the present invention to provide an inexpensive nut having a locking function and not damaging a lens.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to form a predetermined internal thread 2 on a center line of the internal thread 2 and to have a threaded portion 4a having the same diameter as or smaller than the effective diameter of the internal thread. This is achieved by providing a non-screw hole 4 formed by the screw member 4 and a vertical groove 4b that escapes outside the screwed portion 4a to provide a locking nut formed of the resin member 3. By using such a locking nut,
The elastic force of the resin member 3 acts at the time of squeezing, so that the tightening strength in the axial direction is sufficiently ensured. Moreover, since the screwless hole 4 of the resin member 3 is smaller than the screw outer diameter, the screwless hole 4 is tightened by a small screw (or tapping screw) at the time of tightening.
In addition, a screw thread is formed, and the outer surface of the screw is tightened by the elastic force of the resin member 3, so that the screw can be prevented from loosening.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention.
6 through FIG. 1 and 2 show a locking nut A according to the present invention. In the figure, reference numeral 1 denotes a hexagonal nut made of metal, and a predetermined female screw 2 is formed at the center. A resin member 3 having a hexagonal outer shape extends from the rear end of the metal nut 1 and is integrally formed so as to cover the metal nut 1. At the center of the resin member 3 on the center line of the female screw 2, a screw-in portion 4 a having the same size as or a little smaller than the effective diameter of the female screw 2, and a vertical groove portion 4 b escaping outward from the screw-in portion 4 a And the screwless hole 4 formed concentrically with the female screw 2 of the metal nut 1. Usually, about one to three vertical grooves 4b are formed. Further, the resin member 3 is provided at the front end of the metal nut 1.
A bushing portion 5 extending from the metal nut 1 is formed.
Are formed slightly larger than the root diameter of the metal nut 1 and are integrally formed concentrically with the metal nut 1. The locking nut A can be manufactured by a so-called insert molding method in which a metal nut 1 which has been processed in advance is set in a molding die and a resin material is injected, but a nut holding member can be provided in the vertical groove portion 4b. Therefore, the metal nut 1 can be positioned at a predetermined position and held horizontally to accurately perform insert molding. The metal nut 1 is not always required in the lock nut A. The lock nut A entirely formed of the resin member 3 from the female screw 2 to the screwless hole 4 has a sufficient effect. Can be demonstrated.

The locking nut A having this configuration is most suitable for, for example, fixing a lens of borderless glasses. As shown in FIG. 3, the bushing portion 5 of the locking nut A is inserted into the mounting hole 22 of the lens 21 to hold the resin member 3 (hexagonal outer portion), and the flat washer 23 and the metal member 24 (for example, a frame fitting) Etc.) and a metal small screw 25
Is screwed into the female screw 2 of the nut A, and when the screwing is further continued, the tip of the small screw 25 comes into contact with the screwless hole 4 of the resin member 3 and is screwed by the small screw 25 while forming a screw thread. The resin member 3 is made of a polyacetal resin or a polyamide resin.
Since the effective diameter of the female screw 2 is substantially the same as that of the female screw 2, the screw can be easily screwed in. Further, the small screw 25 is tightened by the elastic force of the resin member 3 and the loosening of the screw can be prevented. The small screw 25 may be a tapping screw. In the case of a tapping screw, it is preferable that the diameter of the screwless hole 4 is slightly smaller than the effective diameter.

Next, FIGS. 4 to 6 show another embodiment in which the present invention is modified. The locking nut B shown in FIGS. The other configuration is the same with the lost shape. That is, it is used when the bushing portion 5 is not required.
Is equivalent to

Further, in these embodiments, the outer shape of the resin member 3 may be a shape having a two-sided cut 13 as shown in FIG. 6 or another polygonal shape, and a shape which can be engaged with a tool at the time of tightening is preferable. .

[0010]

As is apparent from the above description, according to the present invention, a predetermined internal thread 2 is formed, and the same diameter as the effective diameter of the internal thread 2 or a smaller diameter than the effective diameter is screwed on the center line of the internal thread 2. This is a locking nut formed by a resin member 3 having a screwless hole 4 formed by a portion 4a and a vertical groove 4b which escapes outside the screwed portion 4a. According to this invention, the elastic force is exerted by being formed of the resin member at the time of tightening, and the tightening strength in the axial direction is sufficiently ensured. In addition, since the screwless hole of the resin member is smaller than the screw outer diameter, a screw thread is formed by a small screw (or tapping screw) at the time of tightening. Looseness can be prevented. Further, since the conventional T-shaped washer is not required by the integrally formed bushing portion, a large number of effects can be obtained, such as good assembling workability, reduced assembling cost, and prevention of lens damage.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a locking 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 locking nut A;

FIG. 4 is a front sectional view showing a locking nut B as another embodiment.

FIG. 5 is a bottom view of FIG. 4;

FIG. 6 is a bottom view showing another embodiment.

FIG. 7 is an explanatory view showing a conventional tightening state.

[Explanation of symbols]

 Reference Signs List 1 metal nut 2 female screw 3 resin member 4 screwless hole 4a screw-in part 4b vertical groove part 5 bushing part 6 inner diameter A locking nut

Claims (1)

[Claims] A predetermined internal thread 2 is formed, and a threaded portion 4a having the same diameter as or smaller than the effective diameter of the internal thread on the center line of the internal thread 2 and a longitudinal portion which escapes outside the threaded portion 4a. A locking nut formed by a resin member having a screwless hole formed by a groove and a resin member.