JPH02283910A - Stepped screw - Google Patents

Abstract

PURPOSE:To fasten a disc spring and so on easily and securely by providing a stepped part in the neighborhood of a head part of a screw, by fitting the disc spring or a washer into the stepped part, and by arranging a locking projection for preventing removal of the disc spring and so on the peripheral surface of the stepped part at an appropriate interval. CONSTITUTION:A disc spring is fitted into a stepped part 3 of a stepped screw 1, and a locking projection 4, which is a projected streak in the longitudinal direction, is formed on the peripheral surface on the lower part of the stepped part 3 at an appropriate interval. The locking projection 4 is formed, for example, by knurling machining by applying a knurling tool to the peripheral surface of the stepped part 3 after a disc spring 2 or a washer is fitted into the stepped screw 1. In this way, the disc spring 2 is set to the stepped screw 1 without removing because of the locking projection 4. As a result, the disc spring or the washer and so on is locked. The locking can be easily done only by providing the projection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a stepped screw used as a set screw or the like for fixing a nine-rotator to a shaft.

[Conventional technology]

Set screws often come with washers, concave springs, etc., but sometimes people forget to include these when tightening the screws. Therefore, if you set a washer or disc spring under the screw head in advance to prevent it from coming out easily, you can prevent forgetting to put it on by simply tightening it.

By the way, in the case of a normal screw, as shown in FIGS. 5 and 6, before forming the threaded portion I, a disc spring α3 or a washer or both are installed under the screw head α.

Thereafter, the threaded portion CI was formed by knurling or the like. In this way, the thread of the threaded part αυ will be aligned with the disc spring a.
This threaded portion aυ projects outward from the inner diameter of the spring 3, and acts as a locking portion for releasing the disc spring αj and the like.

[Problem to be solved by the invention]

In this way, when creating the threaded part αυ with a normal screw,
Although it is possible to easily fasten a disc spring fi3 or the like, a method for fastening the disc spring t13 or the like to the stepped portion of a two-stage screw has not yet been invented.

SUMMARY OF THE INVENTION An object of the present invention is to provide a stepped screw that can easily and reliably fasten a disc spring or the like, thereby reliably preventing forgetting to tighten it when tightening.

[Means to solve the problem]

The stepped screw of the present invention achieves the above object.

The gist of the present invention is to fit a disc spring or a washer into the step, and to arrange locking protrusions at appropriate intervals on the surface of the step to prevent the disc spring or washer from coming off.

[Effect]

According to the present invention, it is possible to easily form a locking protrusion on the stepped portion of a screw with nine steps, thereby preventing the disc spring or washer from coming off, and making it possible to avoid forgetting to attach a disc spring, etc. to the screw with an enhanced force. It can definitely be eliminated.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to nine drawings.

Fig. 1 is a partially cutaway front view showing an embodiment of the stepped screw of the present invention, and Fig. 2 is a partially cutaway front view showing the same manufacturing process. Reference numeral 21 indicates a disc spring.The disc spring (21 is fitted into the stepped part 13) of the loaded screw (1), and locking protrusions (41) formed by longitudinal protrusions are placed at appropriate intervals on the surface of the stepped part 13 below it. The locking protrusion (
The degree of protrusion 4) was set to be larger than the inner diameter of the IIn spring 12+.

This locking protrusion 141 is formed by fitting a concave spring (21) into a ready-made stepped screw (1), as shown in FIG.

A knurling (5) is applied to the curved surface of the stepped portion (3), and the step is formed by knurling. In this way, the locking protrusion (4
), the disc spring (2) is set in the stepped screw part 1).

The next disc spring (stepped screw (1) with 21 set)
To explain an example of its use, as shown in Fig. 3, a rotating member (
In contrast to 6), when the shaft 17) is fitted using the serrated shaft structure, the boss portion of the rotary member 16) is stopped midway without passing through, and a through hole (8) is provided in the upper closed portion.

On the other hand, at the center position of the shaft (71), a screw hole into which the tip of the set screw is inserted is formed from the end toward the inside.
Insert the stepped screw (1) as a set screw from the opposite side to the insertion direction of the shaft]7), and insert the tip threaded part 19) into the shaft 17).
Screw together. At that time, the step (3) of the screw (1) passes through the closed part of the boss part of the rotating member 16), and in this case, there is some clearance between the step 13) and the through hole 18). exist. ), the screw part 19) was made so as not to touch the boss part at all.

In this way, the torque of the shaft (7) is transmitted to the rotating member (6) via the serrated shaft structure, but the rotating member (61) and the stepped screw (1) are slightly Since there is only a line contact with the 9-stage screw (
Torque from the shaft 17+ or from the rotating member (6) is transmitted to 11, and as a result, the screw (1) does not loosen.

FIG. 4 shows another embodiment of the stepped screw (11) of the present invention, in which nine locking protrusions (four protrusions one point above) of the disc spring (2) are arranged at appropriate intervals on the surface of the stepped portion 131. It may be arranged in an array.

〔Effect of the invention〕

As mentioned above, the stepped screw of the present invention makes it possible to lock a disc spring or washer, etc. at the stepped portion, which was previously considered impossible, and this locking can be achieved by simply providing a protrusion. Since it can be done with a simple structure, it can be manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view showing an embodiment of the stepped screw of the present invention, Fig. 2 is a partially cutaway front view showing the manufacturing process of the same, and Fig. 3 is a partially cutaway front view of the stepped screw of the present invention. FIG. 4 is a partially cutaway front view showing another example of the stepped screw of the present invention, and FIGS. 5 and 6 are a partially cutaway front view showing a conventional example. It is a front view. (1)...Stepped screw +3)...Stepped part (5)...Knurl 171...Shaft 19)...Threaded part lL...Screw head (2)...Countersunk Spring (4)...Locking protrusion (61...Rotating member (8)...Threaded hole aD...Threaded part a3...Disc spring

Claims (2)

[Claims] (1) A stepped screw characterized in that a disc spring or washer is fitted into the stepped part, and locking protrusions for preventing the disc spring or washer from coming off are arranged at appropriate intervals on the circumferential surface of the stepped part. (2) The stepped screw according to claim 1, wherein the locking protrusion is a vertical protrusion formed by knurling.