JP2001208025A - Clamping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clamping device which achieves light weight and reduced cost without changing structural material. SOLUTION: This clamping device, having a threaded portion 2 on an external or internal circumference, comprises a main body which combines several members together with an engaged member such as nut to be engaged with the threaded portion 2 and the engaged member. In addition, at least a hollow- shaped hole 3 is formed in an area of the threaded portion 2. Further, it is preferred that an inner diameter of the hole 3 is formed without the range of 25 to 50% of a nominal diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastener such as a bolt for coupling a plurality of members in cooperation with an engaged member called a nut, for example.

[0002]

2. Description of the Related Art In recent product development, recycling consciousness is increasing from the viewpoints of weight reduction for improving portability and environmental protection, as well as low price and high quality. Therefore, even fasteners such as bolts are manufactured without any exception, taking into account the weight saving while maintaining the tightening strength and compatibility for reuse.

[0003]

[Problems to be Solved by the Invention] However, since bolts and the like have standard dimensions of each part determined by JIS, it is necessary to maintain a constant shape, and to reduce the weight by devising the shape. It is difficult. On the other hand, in order to reduce the weight, it is also possible to form with a special lightweight metal. However, the rise in the price of raw materials is reflected in the rise in commodity prices, and cannot meet the demand for low prices. In particular, ornaments such as spectacles are often formed of a noble metal for decoration, and it is difficult to easily change materials such as bolts.

[0004] An object of the present invention is to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a fastener capable of reducing cost and weight.

[0005]

In order to achieve the above object, a fastener according to claim 1 has a threaded portion on an outer periphery or an inner periphery, and cooperates with an engaged member engaged with the threaded portion. In the fastener for operating and coupling a plurality of members, a hollow hole is formed from the head of the fastener to the lower end of the screw portion. This makes it possible to reduce the cost and weight while maintaining the appearance and within the range defined by JIS.

A second aspect of the present invention provides a fastening tool having a threaded portion on an outer periphery or an inner periphery for coupling a plurality of members in cooperation with an engaged member engaged with the threaded portion. In the fastener comprising the main body and the engaged member, a hollow hole is formed in at least the screw portion. This makes it possible to reduce the cost and weight while maintaining the appearance and within the range defined by JIS. In addition, if a hollow hole is provided only in the screw portion, the hollow portion is not exposed on the head, which is more preferable for decoration.

Further, according to a third aspect of the present invention, in addition to the above-mentioned respective fasteners, the inner diameter of the hollow hole is 25 times the nominal diameter.
-50%. This allows
It is possible to reduce the weight by about 13 to 25% as compared with the conventional product, the bending direction stress becomes a sufficient value, and the stability is improved.

[0008] The fastener according to claim 4 is characterized in that one hollow hole is provided along the central axis. This makes it easier to form a hollow hole and also increases the bending direction stress.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a first embodiment of a fastener according to the present invention, and is a front view and a side view thereof.

In the first embodiment, the hexagonal bolt is composed of a head portion 1 as a force receiving portion and a screw portion 2 having a thread, and is arranged along the central axis of the bolt from the lower end position of the head portion 1. A cylindrical hollow portion 3 is formed up to the lower end of the screw portion 2.

The hollow portion 3 is a bottomed hole having the bottom of the head 1, and extends over a portion corresponding to the screw portion 2 and a portion between the screw portion 2 and the head 1. Is formed. The inner diameter W2 of the hollow portion 3 is 50% of the nominal diameter W1 of the screw portion 2. The hollow part 3 is formed only between the upper end and the lower end of the screw part 2 without penetrating to the upper part of the head 1. Therefore, it is effective when a hole cannot be exposed in the upper part of the head 1 that is visible for decoration.

FIG. 2 is a front view and a side view showing a second embodiment of the present invention. This hexagon socket set screw is also
It is composed of a head portion 11 as a force receiving portion and a screw portion 12 having a thread. A hexagonal receiving groove 1 formed on the upper surface of the head 11 along the central axis of the set screw.
A cylindrical hollow portion 13 is formed up to the lower end of the screw portion 12 so as to be in contact with the screw portion 4. That is, this hollow portion 1
3 is a through hole. The inner diameter W12 of the hollow portion 13 is about 44% of the nominal diameter W11 of the screw portion 12.

FIG. 3 is a front view and a side view showing a third embodiment of the present invention. This small bolt is also composed of a head portion 21 as a force receiving portion and a screw portion 22 having a thread. A cylindrical hollow portion 23 is formed from the head 21 to the lower end of the screw portion 22 along the center axis of the bolt. This hollow portion 23 is also formed as a through hole, and one end thereof is formed in contact with the screw groove 24. The inner diameter W22 of the hollow portion 23 is about 35% of the nominal diameter W21 of the screw portion 22.

The second embodiment differs from the first embodiment in the shape of the hexagonal hole serving as the force receiving groove 14 and the shape of the hollow portion 13. However, the hollow portion 13 is not formed as a through hole. , First
It may be a bottomed hole as in the embodiment. Alternatively, the hexagonal hole may be formed as the hollow portion 13 as it is without forming the hollow portion 13 into a columnar shape, and the hollow portion 13 may be formed up to the lower end of the screw portion 12, thereby forming a hollow portion having a prismatic shape. In the small bolt of the third embodiment, the thread groove 24 is formed in a slot shape, but may be formed as a cross hole.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 is a side view of the fastener and a bottom view as viewed from the lower end of the screw portion.

The tightening tool of the fourth embodiment is a cross-headed bolt, and is composed of a head 31 having a cross-shaped hole (not shown) as a force receiving groove and a screw portion 32 having a thread. A hollow portion 33 is formed in a cylindrical shape up to the lower end of the screw portion 32 so as to contact the cross hole of the head portion 31 along the central axis of the bolt.
Are formed. Here, the inner diameter W32, which is the diameter of the cross-sectional area of the hollow portion 33, is 50% larger than the nominal diameter W31 of the screw portion 32.

The bolt having the through-hole according to the second or fourth embodiment is connected to a nut (an engaged member indicated by 35 in FIG. 4).
When ultrasonic vibration was applied in a state where the bolts and nuts of the same standard dimensions were loosened (the nut 35 moved in the direction of arrow A in FIG. 4), On the contrary, the bolt and the nut 35 of the fourth embodiment have the effect of being tightened (the nut 35 moves in the direction of arrow B in FIG. 4).

This is presumably because conventional nuts and bolts have different natural frequencies due to differences in cross-sectional shape, resulting in a difference in transmission of vibration and slackening. On the other hand, in the fastening device of the present invention, the cross-sectional shape of the main body portion serving as the bolt has the same shape as that of the nut serving as the engaged portion, and the natural frequencies of the bolt and the nut 35 are similar.
Is tightened (the nut 35 moves in the direction of arrow B in FIG. 4).

Further, in each of the above embodiments, the inner diameters W2, W12, W22, W22 of the hollow portions 3, 13, 23, 33 are provided.
32 is a nominal diameter W1, W of the thread portion 2, 12, 22, 32.
11, 50%, 44%, 35 compared to W21, 31
% And 50%, but this value may be another value. As a result of many trials, when the inner diameter of the hollow portion is set to 25 to 50% as compared with the nominal diameter of the thread portion, it is advantageous in terms of weight reduction and cost reduction while maintaining strength as a fastener.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view of a state where the fastener is fitted to the member.

In the fifth embodiment, a hexagonal bolt having a hollow portion 43 is fitted to members 44a and 44b. Further, a screw portion 42 is formed in the hollow portion 43, and serves as a screw hole. By using the small screw 45 as a male screw and screwing into the hollow portion 43 as a screw hole, another member, for example, the substrate 46 can be locked.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a side view of the fastener of this embodiment.

In the sixth embodiment, a fastener is constituted by the hexagonal bolt 50, the nut 60, and the small screw 61. The hexagonal bolt 50 includes a head portion 51 as a force receiving portion, and a screw portion 52 having a screw thread on the inner and outer circumferences. A hollow portion 53 serving as a through hole is provided along the central axis of the hexagon bolt 50. Threads are also provided on the outer periphery of the hollow portion 53 (corresponding to the inner periphery of the screw portion 52). The nut 60 is engaged with the outer thread, and the small screw 61 is engaged with the inner thread. Between the head 51 and the nut 60,
A member to be fastened between the head 51 and the small screw 61 is inserted.

In each of the above embodiments, the weight is reduced by forming the hollow portion, and the cost is reduced by reducing the material. In addition, by forming the cross section of the threaded portion into a pipe shape, the stress in the bending direction is increased, and the force is stabilized. In the case of performing heat treatment, the treatment, for example, carburizing and quenching treatment is also performed on the surface of the hollow portion, and the distortion of the screw portion is greatly reduced. Therefore, the damping ability is improved, and the reliability is improved.

Further, when the present invention is applied to a screw for eyeglasses, a screw for jewelry made of noble metal, and the like, the weight of the screw portion is reduced, and the weight as a whole is reduced. In addition, the cost can be significantly reduced due to the reduction in the number of materials. Further, the bolts of the present invention can be used for fixing various parts of a moving body such as an automobile and a train where generation of microvibration is considered. Furthermore, in the case of large-diameter connections, it can be used to fix parts on architectural overpasses, and it can also be used for fixing parts of high-speed punching dies (cutting dies such as lead frames), which is also effective as a locking device. is there. You.

In each of the above embodiments, only one hollow portion is provided along the center axis of a bolt or the like, but a plurality of hollow portions may be provided in the axial direction. In this case, various methods are adopted, such as providing a hollow portion along the central axis and a plurality of hollow portions around the central portion, or providing no hollow along the central axis, and providing a plurality of hollow portions around the central axis. obtain.

[0027]

As described above, the fastener according to each claim has a hollow portion, so that it is possible to significantly reduce weight and cost while maintaining strength.

[Brief description of the drawings]

FIG. 1 is a view showing a hexagonal bolt according to a first embodiment of the present invention, in which (A) is a front view and (B) is a half sectional side view.

FIGS. 2A and 2B are views showing a hexagon socket set screw according to a second embodiment of the present invention, wherein FIG. 2A is a front view and FIG.

FIGS. 3A and 3B are views showing a small bolt according to a third embodiment of the present invention, wherein FIG. 3A is a front view and FIG. 3B is a half sectional side view.

FIG. 4 is a view showing a cross-headed bolt according to a fourth embodiment of the present invention, wherein (A) is a side view and (B) is a rear view.

FIG. 5 is a cross-sectional view illustrating a state where a hexagon bolt and a small screw according to a fifth embodiment of the present invention are tightening a member.

FIG. 6 is a side view of a fastener including a hexagon bolt, a nut and a small screw according to a sixth embodiment of the present invention.

[Explanation of symbols]

 1, 11, 21, 31, 41, 51 Head 2, 12, 22, 32, 42, 52 Screw 3, 3, 23, 33, 43, 53 Hollow 24 Screw groove 35 Nut 44a, 44b Member 45, 61 Small screw 46 Board (member) 50 Hex bolt 60 Nut

Claims (4)

[Claims] 1. A fastener for coupling a plurality of members in cooperation with a member to be engaged which has a screw portion on an outer periphery or an inner periphery thereof, said head portion of said fastener. A fastener having a hollow hole extending from the lower end to the lower end of the screw portion. 2. A body having a threaded portion on an outer periphery or an inner periphery for coupling a plurality of members in cooperation with an engaged member engaged with the threaded portion; Wherein a hollow hole is formed in at least the screw portion. 3. An inner diameter of the hollow hole is 25 to a nominal diameter.
3. The method as claimed in claim 1, wherein said metal is formed at 50%.
The described fastener. 4. The fastener according to claim 1, wherein one of the hollow holes is provided along a central axis.