JP2018031440A - Fastening member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening member capable of stably disposing a nut on an arbitrary position with a simple structure, and free from loosening for a long period.SOLUTION: A fastening member 1 has a first nut 2 and a second nut 3 having regular polygonal column-shaped side faces, and a casing member 4 having a regular polygonal side wall and accommodating the first nut 2 and the second nut 3, and the first nut 2 and the second nut 3 are accommodated in the casing member 4 in a state that their shaft centers are aligned and their screw phases are deviated from each other. The casing member 4 is provided with an elastic portion 7 for adding axial force to a horizontal face of the first nut 2, and a restricting portion 8 for restricting axial motion of the second nut 3.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fastening member which is attached to a bolt which is a male screw and hardly loosens after fastening.

Fastening with a combination of bolts and nuts is a simple fastening means and has been used in various fields such as machinery and construction. However, there are many cases where the fastening is loosened due to unintentional rotation of the nut due to vibration or the like after fastening. For this reason, periodic inspection and maintenance work is required in facilities that are used for a long period of time, but this requires a lot of labor.

Furthermore, loosening becomes a problem especially when it is desired to install the nut at an intermediate position of the bolt. When a bolt is passed through a hole in a plate-like member and the nut is tightened at a position in contact with the plate-like member, an elastic force is generated as a reaction force between the plate member surface and the nut by using a spring washer. Thereby preventing the nut from loosening. However, in a state where it is not in contact with a fixed object other than the bolt, a reaction force that increases the frictional force between the nut and the bolt cannot be obtained, and there is no effective means for preventing the nut from loosening.

Patent Document 1 describes that bolts and nuts are prevented from loosening by a double nut structure.

Japanese Patent Laid-Open No. 2009-275727

In the conventional fastening member, the nut cannot be stably installed at the intermediate position of the bolt. In the locking device for locking according to Patent Document 1, the abutting convex portion of the upper nut and the abutting step end portion of the fastening bolt are brought into contact with the tapered through hole receiving portion of the lower nut, and gradually from the leading end portion. Wedge structure that tightens evenly around the entire circumference, double nut structure by reverse tightening of the upper nut and lower nut, and the outer peripheral angle of the tip of the abutment convex part of the upper nut and fastening bolt in the groove of the tapered through hole receiving part It is complicated to use a biting structure that bites the part. In addition, as shown in each drawing of the same document, only a coupling form in which a nut is fastened to a fixed object is used, and there is no description or suggestion about attaching to a middle part of a bolt.

An object of the present invention is to provide a fastening member that has a simple structure and can stably install a nut at an arbitrary position and is less likely to be loosened for a long period of time.

In order to solve the above-described problems, a fastening member of the present invention includes a first nut and a second nut having regular polygonal columnar side surfaces, and a regular polygonal side wall for accommodating the first nut and the second nut. The first nut and the second nut are housed in the casing member with their axes aligned and shifted in phase with respect to each other. The casing member is axially aligned with the horizontal surface of the first nut. The elastic part which applies this force and the restricting part which restricts the axial movement of the second nut are formed. The first nut and the second nut may be hexagonal nuts, and the casing member may be hexagonal columnar. It is preferable that the phase shift between the screws of the first nut and the second nut is 1/3 or more and 2/3 or less of the entire circumferential angle.

When the fastening member of the present invention is attached to the bolt, the inner nut is pressed against the bolt with a strong force at any position on the bolt, thereby preventing relative rotation of the nut with respect to the bolt. . Since the pressing force acts on the two nuts in opposite directions, when an external force is generated due to vibration or the like, the direction in which each nut tries to rotate is opposite. It cancels out and rotation is prevented. It has a simple structure and does not require special tools for installation and removal.

It is sectional drawing which shows a fastening member. It is a perspective view which shows a casing member. It is a perspective view which shows a 1st nut. It is a perspective view which shows a 2nd nut. It is sectional drawing which shows the effect | action of a fastening member. It is a perspective view which shows the 2nd example of a 2nd nut. It is a perspective view which shows the 2nd example of a fastening member. It is a perspective view which shows the usage example of a fastening member.

EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated in detail based on drawing. FIG. 1 is a cross-sectional view showing a fastening member. The fastening member 1 of the present invention includes a first nut 2 and a second nut 3 having regular polygonal columnar side surfaces, and a casing member 4 having a regular polygonal side wall and housing the first nut 2 and the second nut 3. And have. 2 is a perspective view showing a casing member, FIG. 3 is a perspective view showing a first nut, and FIG. 4 is a perspective view showing a second nut.

The first nut 2 and the second nut 3 have a substantially regular polygonal column shape, and may be, for example, a square shape. In this example, the first nut 2 and the second nut 3 have a regular hexagonal column shape in the same manner as a widely used nut. By using a regular hexagon, conventional manufacturing equipment can be diverted, and a normal spanner or the like can be used as it is as a tool for fastening. The first nut 2 is a normal hex nut. The second nut 3 may also be a normal hex nut, but in this example, the concave portion 5 is provided on the side surface. The recess 5 may be provided on only two opposing surfaces, but here, it is provided on all six side surfaces. In addition, the first nut 2 and the second nut 3 are formed with a taper 6 at the threaded portion on the side (lower side in FIG. 1) that serves as a bolt insertion opening, and an opening shape that gradually widens toward the lower surface. ing.

The casing member 4 also has a regular polygonal columnar side wall, but corresponds to the surface shape of the first nut 2 and the second nut 3. In this example, it is a regular hexagonal cylinder, and the inner wall surface is approximately the same size as or slightly larger than the side surfaces of the first nut 2 and the second nut 3, but the first nut 2 and the second nut 3. When the nut is housed inside, the rotation of the first nut 2 and the second nut 3 is not allowed to be allowed.

The casing member 4 is provided with an elastic portion 7 that applies an axial force to the horizontal surface of the first nut 2. In this example, the elastic part 7 is formed so as to act as a leaf spring by performing a quenching process after folding one end of the casing member 4 inward. When a force to be pushed up by the first nut 2 is applied, the first nut 2 is deformed in accordance with the force to allow the movement of the first nut 2 to some extent, and the amount of deformation (the amount of movement of the first nut) Accordingly, an elastic force is generated to push back the first nut 2. The strength of the elastic portion 7 as a spring is set in accordance with the degree of prevention of loosening at the time of fastening, and can be adjusted by, for example, the material and thickness of the bent portion, the bending angle, or the quenching temperature.

The casing member 4 is also formed with a restricting portion that restricts the axial movement of the second nut 3. For example, after housing the first nut 2 and the second nut 3 in the casing member 4, the opposite end (lower side in FIG. 1) of the casing member 4 can be bent inward. In this case, a normal hex nut can be used as the second nut, but it is preferable to re-harden the bent portion in order to obtain a sufficient regulating force. In this example, the protrusion 8 that engages with the recess 5 of the second nut 3 is provided on the casing member 4 as a restricting portion. In the wall surface of the casing member 4, two cuts 9 perpendicular to the length direction are made in parallel, and a projection 8 is formed by pressing a portion between the cuts 9 inward. By selecting the interval between the two notches 9 in accordance with the width of the recess 5 of the second nut 3, it can be made to enter the recess 5 approximately.

The fastening member 1 shown in FIG. 1 is obtained by sequentially inserting the first nut 2 and the second nut 3 from the lower opening of the casing member 4. At this time, the 1st nut 2 and the 2nd nut 3 are thrown in from the exit side of a bolt, ie, the side where the taper is not formed, respectively. When inserting the second nut 3, it is necessary to shift the phase of the screw of the first nut 2 with respect to the second nut 3.

Here, the screw phases of the first nut 2 and the second nut 3 will be described in detail. A bolt is inserted from the inlet side of the second nut 3 with no gap between the first nut 2 and the second nut 3, and after passing through the second nut 3, the tip of the bolt is placed on the inlet side of the first nut 2. When the bolt reaches the threaded portion of the first nut 2 as it is, it is assumed that there is no phase shift. In order to set in the casing member 4, the angle of the second nut 3 can be selected as an intermittent angle change corresponding to the number of regular polygons. For example, in the case of a regular hexagon, only an angle change of 60 ° can be selected. Of these 60 ° angles, the smallest phase shift is avoided.

FIG. 5 is a sectional view showing the operation of the fastening member. The first nut 2 and the second nut 3 are housed in the casing member 4 with their axes aligned and the phases of the screws shifted from each other. For example, it is assumed that the phase of the screw of the second nut 3 is delayed with respect to the first nut 2 by 180 ° and is housed in the casing 4. In this case, when the tip of the bolt that has passed through the second nut 3 reaches the screw portion on the inlet side of the first nut 2, the bolt cannot directly enter the screw portion of the first nut 2. When the bolt is further rotated, the tip of the bolt pushes up the first nut 2. The first nut 2 advances in the axial direction while deforming the elastic portion 7 of the casing member 4, and a gap is formed between the first nut 2 and the second nut 3. When a gap corresponding to 1/2 of the pitch length P of the screw is formed between the first nut 2 and the second nut 3, the bolt comes into engagement with the threaded portion of the first nut 2. Thereafter, the tip of the bolt passes through the threaded portion of the first nut 2 and also passes through the casing member 4.

However, a gap of 1/2 of the pitch length P is maintained between the first nut 2 and the second nut 3, and the deformation of the elastic part 7 caused by this causes the first nut 2 and the second nut 3 to be mutually connected. A force in the direction of approaching is applied. Therefore, the screw portion of the first nut 2 is pressed downward with respect to the male screw portion of the bolt, and the screw portion of the second nut 3 is pressed upward with respect to the male screw portion of the bolt. Thus, a frictional force that prevents relative rotation with respect to the bolt is generated in both the first nut 2 and the second nut 3. This frictional force is similarly generated regardless of the position of the fastening member 1 on the bolt. Therefore, even if it is in the middle position of the bolt which is not in contact with other fixed objects, rotation of fastening member 1 is prevented. Even if a force is applied to rotate the nut due to vibration, rotation is prevented by this frictional force. Even when a rotational force exceeding the frictional resistance is applied, the two nuts are pressed against each other in the opposite directions against the bolts, so the two nuts try to rotate in the opposite directions. In the example of FIG. 5, a downward pressing force is applied to the first nut 2 and attempts to rotate in the first direction corresponding to this. On the other hand, since the same magnitude of force is applied upward to the second nut 3, the second nut 3 tries to rotate in a second direction opposite to the first direction. And since the 2nd nut 3 and the 3rd nut 3 are accommodated in the casing member and can rotate only in the same direction as one, the mutual rotational force is canceled and the fastening member 1 does not rotate. Even if an external force such as vibration is applied after installation, loosening is unlikely to occur. This frictional force is sufficient to prevent unintentional natural loosening, but not excessive. If a normal tool such as a spanner is used to rotate, it can be easily rotated without applying too much force. Therefore, the fastening member 1 can be removed or the fastening position can be changed without any problem when necessary. it can.

As described above, the case where the phase shift of the screw of the first nut 2 and the second nut 3 is ½ of the entire circumferential angle, that is, 180 ° has been described. By changing the phase shift, the size of the gap between the first nut 2 and the second nut 3 generated at the time of fastening also changes, and the frictional force that hinders rotation also changes. Setting the phase shift of the first nut and the second nut to 1/3 or more and 2/3 or less of the entire circumferential angle, that is, 120 ° or more and 240 ° or less can obtain sufficient frictional force and This is preferable because biting is less likely to occur. Among these, 1/2 of the total circumferential angle is particularly preferable.

Next, another embodiment of the fastening member will be described. FIG. 6 is a perspective view showing a second example of the second nut, and FIG. 7 is a perspective view showing a second example of the fastening member. In this example, a flange portion 10 is provided at the end of the second nut 3 on the inlet side (lower side in FIG. 6). The flange portion 10 may be formed integrally with the nut body, but here, an annular member such as a plain washer is fixed by welding.

The flange portion 10 can be used to attach to the surface of the object y to which the bolt is attached. FIG. 8 is a sectional view showing an example of use of the fastening member of this example. Bolt-through holes 11 are provided in the object, the screw holes of the fastening member 1 are aligned with the holes, and the flange portion 10 can be fixed to the object y by welding. If there is a plane that is in contact with the flange portion 10, the object y can be arbitrarily selected.

The bolt x can be attached by inserting the bolt x from the bolt through hole 11 of the object y and screwing it into the fastening member 1. It is not necessary to tighten until the head of the bolt x hits the object. You may install in the state which the volt | bolt protruded from the surface of the target object. Even in such a state, the first nut 2 and the second nut 3 in the casing member 4 can exert a sufficient frictional force on the bolt and do not loosen naturally after installation. Various things can be attached between the bolt and the surface of the object. For example, a wide flat washer 12 can be placed at the head of the bolt x, and a soft member such as a sponge 13 can be attached between the surface of the steel plate as the object y and the flat washer 12 while keeping its bulge. Further, the movable member can be attached without being tightened.

1. Fastening member 2. First nut 3. Second nut 4. Casing member 5. Recess 7 Elastic part 8. Regulatory part 10. Flange part x. Bolt y. Attachment object

Claims (3)

A first nut and a second nut having a regular polygonal columnar side surface; and a casing member having a regular polygonal side wall and accommodating the first nut and the second nut, wherein the first nut and the second nut are The casings are accommodated in the casing member with the axes aligned and the phases of the screws shifted from each other. The casing member is provided with an elastic portion that applies axial force to the horizontal surface of the first nut and the axial movement of the second nut. The fastening member in which the control part which controls is formed. A first nut and a second nut having hexagonal columnar side surfaces; a casing member having a hexagonal side wall and housing the first nut and the second nut; and a flange portion fixed to one end of the second nut. The first nut and the second nut are accommodated in the casing member with their axes aligned and shifted in phase with respect to each other, and the casing member is elastic to apply an axial force to the horizontal surface of the first nut. The fastening member in which the control part which controls the motion of the axial direction of a part and a 2nd nut is formed. The fastening member according to claim 1 or claim 2, wherein a phase shift between the screws of the first nut and the second nut is 1/3 or more and 2/3 or less of the entire circumferential angle.

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