JP2518764Y2 - Double lock nut - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double lock nut having two nuts, one for fastening and one for locking.

[0002]

2. Description of the Related Art Generally, when vibration or impact is applied to a nut, a gap is instantaneously created between the nut and the tightening surface, the load is not applied to the nut, the frictional force is lost, and the nut is loosened. It is known.

For this reason, it has been conventionally performed to prevent loosening by a double lock nut that uses a lock nut in addition to the fastening nut. That is, as for the double lock nut, as shown in FIG. 6, after tightening the fastening nut A onto the bolt B until it hits the washer C, the lock nut D is tightened until it comes into contact with the fastening nut A, and then the fastening nut. A is returned by a small amount, or the lock nut D is further tightened with a wrench while the fastening nut A is fixed with a wrench, so that the fastening nut A and the lock nut D are in the arrow X direction and the arrow Y. The upper lock nut D is pushed up, and the thread d of the lock nut D is screwed into the bolt B.
The thread a of the fastening nut A is pressed from the upper side to the thread b of the bolt B with the thread a of the fastening nut A being pushed down.

According to this, the lock nut D receives the tightening load, and the rotation of the lock nut D is prevented by the interference between the lock nut D and the tightening nut A, which causes vibration and the like. However, the nuts A and D will not loosen.

[0005]

However, according to the above double lock nut structure, as shown in FIG. 7, in the case where the return operation of the fastening nut A after tightening the lock nut D is neglected. The nuts A and D do not interfere with each other, and therefore the two nuts A and D
Despite the fact that the nuts are tightened with one nut, the specified locking action does not work and vibrations etc. are applied, it is easy to use both nuts A and D.
Will loosen.

[0006] Accordingly, the present invention is, without the need for a return operation of the fastening nut after tightening the lock nut, can be done lock securely, moreover, both the nut, Rokkuna'
The simple operation of rotating the
Can be screwed in quickly and easily, improving workability.
It is an object to provide a double lock nut that can perform high speed tightening .

[0007]

That is, the present invention is a double lock nut comprising a fastening nut and a lock nut, wherein the end surface of the lock nut on the contact side with the fastening nut is the shaft of the lock nut. The inclined surface intersects the center obliquely, and the outer peripheral surface of the end portion on the inclined surface side is cylindrical, while the end surface of the fastening nut on the contact side with the lock nut surrounds the screw hole. cylindrical part is continuously provided in, and the cylindrical portion, the cylindrical end portion of the inclined surface of the lock nut, the tip of the cylindrical portion is fitted in a state pressed against the outer circumferential surface thereof, said cylindrical lock the lock nut part is, and around the fastening nut co when going by screwing the lock nut to the bolt, with respect to the fastening nut when stopped rotating in contact with the fastening nut clamping surface Nuts Wherein the inclined surface is engaged by the frictional force so as to relatively rotate while being slanted in the direction of contact surface on the end face of the clamping nut.

[0008]

[0009]

According to the above construction , since the end surface of the lock nut on the contact side with the fastening nut is an inclined surface, when the fastening nut is tightened into the bolt and then the lock nut is screwed in, the lock nut is locked. From the time when the nut hits the fastening nut, the clearance of the engaging portion between the lock nut and the bolt is rotated while tilting in the direction in which the inclined surface of the lock nut makes surface contact with the end surface of the fastening nut. A bending moment acts on the bolt, and a reaction force against the bending moment is generated in the bolt, so that the lock nut and the fastening nut are securely fixed to the bolt.

In the conventional double lock nut shown in FIG. 6, the fastening nut A is screwed into the bolt B, then the lock nut D is screwed in, and then the fastening nut A is returned or rotated. Since it is necessary to further tighten the lock nut D while the fastening nut A is fixed, workability is poor and high-speed tightening may not be possible.

On the other hand, according to the present invention, the outer peripheral surface of the end portion on the inclined surface formed on the contact side of the lock nut with the tightening nut is made cylindrical, while the lock nut of the lock nut is the thin-walled cylindrical portion surrounding the screw holes on the end face of the contact-side consecutively provided, and the cylindrical portion, the cylindrical end portion of the inclined surface of the lock nut on the outer peripheral surface of the distal end of the cylindrical portion pressed It is fitted in a state that sometimes the locknut cylindrical portion, the bolt is rotated together with fastening nut when going by screwing the lock nut to, and rotation stop in contact with the fastening nut clamping surface The lock nut is engaged with the fastening nut by a frictional force such that the inclined surface of the lock nut rotates relatively while tilting in a direction in which the end surface of the lock nut is in surface contact with the end surface of the fastening nut. The other side When the lock nut is screwed to the tip of the bolt and the lock wrench is engaged with the lock nut to rotate the lock nut, the portion of the lock nut on the protruding side of the inclined surface is crimped to the fastening nut. ,
By the crimping force and the engagement in the cylindrical portion, the relative postures of both nuts are accurately regulated, and the fastening nuts rotate together, so that both nuts rotate integrally and quickly to the bolt. Be screwed into. Then, when the fastening nut hits the tightening surface and an axial force of the bolt more than the crimping force of both nuts is applied to the fastening nut, the rotation of the fastening nut is stopped and, in the lock nut, a thin-walled cylinder. While the tip of the part is slightly deformed, the inclined surface of the lock nut is rotated while inclining in a direction in which it makes surface contact with the end surface of the fastening nut. As a result, a bending moment acts on the bolt and a reaction force against the bending moment acts on the bolt. Occurs, and the lock nut and the fastening nut are securely fixed to the bolt. Therefore, both nuts can be screwed into the bolt at the same time and at high speed by a simple operation of simply rotating the lock nut, and a reliable lock can be applied.

[0012]

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

As shown in FIGS. 1 to 3, a double lock nut X according to the present invention comprises a fastening nut 1 and a lock nut 2, and the fastening nut 1 has an upper end on one end surface thereof. A thin-walled cylindrical portion 4 surrounding the screw hole 3 centered on the screw hole 3 is provided continuously, and a bent portion 5 slightly bent inward is formed at the tip of the cylindrical portion 4. It In addition, a screw hole 6 is formed in the lock nut 2 and the fastening nut 1
The outer periphery of the lower end portion 7 facing toward the front side is formed into a cylindrical shape, and the portion 7 is closely fitted to the tip of the bent portion 5 of the fastening nut 1, and is fitted into the cylindrical portion 4. Are connected.

This fitting is performed manually by the fastening nut 1.
The lock nut 2 cannot be pulled out from the lock nut 2, and the frictional force generated in this portion further causes the lock nut 2 to be screwed into the bolt 11 (see FIG. 4). When the fastening nut 1 co-rotates with the crimping force acting on the fastening nut 1 from the 2 side and the fastening nut 1 is pressed against the washer 12 shown in FIGS. 4 and 5, the lock nut 2 is fastened to the fastening nut 1. It is sized to rotate relative to. In addition, as shown in FIG. 1, the fastening nut 1 and the lock nut 2 are connected to the lock nut 2 with their diagonals displaced so that a torque wrench described later can be fitted only to the lock nut 2. There is.

Further, the lower end surface of the lower end portion 7 facing the fastening nut 1 side is an inclined surface 8 that obliquely intersects the axis of the lock nut 2. In that case, the angle θ of the inclined surface 8 is as little 2 about ⁰ to 1 ^0, 1 to
In FIG. 5, the existence of the inclined surface 8 is exaggerated for easy understanding.

In the use of the double lock nut X as described above, when the block 10 is attached to the base 9 as shown in FIG. 3, the lower end portion 7 of the lock nut 2 is press-fitted to the cylindrical portion 4 of the fastening nut 1. And the nuts 1 and 2 are connected together, the lower end portion side of the fastening nut 1 where the cylindrical portion 4 is not formed is slightly attached to the tip of the bolt 11 passing through the base 9 and the block 10 (for example, After engaging the screw (about one thread), an impact wrench is engaged with the upper lock nut 2 from above, and the lock nut 2 is rotated by the impact wrench. Then, since the lower end surface of the lock nut 2 is the inclined surface 8, the inclined surface 8
Since the corner portion 8a that protrudes downward is crimped to the fastening nut 1, the fastening nut 1 and the lock nut 2
And the two nuts 1 and 2 are connected to each other in a press-fitted state in the cylindrical portion 4 and the relative postures of the nuts 1 and 2 are accurately maintained. , 2 are integrally screwed into the bolt 11. Then, the fastening nut 1 hits the washer 12, and a load equal to or greater than the above-mentioned crimping force of the nuts 1 and 2 (axial force of the bolt 11).
When the lock nut 1 is engaged with the lock nut 1, the rotation of the lock nut 1 is stopped and, in the lock nut 2, the lower end surface of the lock nut 2 is an inclined surface 8. As much as the clearance of the meshing portion with 11, the taper surface 8 of the lock nut 2 rotates while tilting in the direction in which the taper surface 8 of the lock nut 2 comes into surface contact with the end surface of the fastening nut 1, as a result, a bending moment acts on the bolt 11, The bolt 11 is bent in the MM direction in FIG. 5, and a reaction force against the bending moment is generated in the bolt 11,
The lock nut 2 and the bolt 11 are firmly crimped at the portion indicated by the arrow A, and the fastening nut 1 and the bolt 11 are firmly crimped at the portion indicated by the arrow B, whereby the nuts 1 and 2 are locked. It

Therefore, according to this double lock nut structure, both nuts of the lock nut 2 and the tightening nut 1 can be tightened only by tightening the lock nut 2 with an impact wrench, and the lock nut can be screwed in as in the conventional case. The subsequent returning operation of the fastening nut 1 or the tightening operation of the lock nut 1 in the fixed state of the fastening nut 1 becomes unnecessary, so that the locking operation becomes simple and fast fastening can be performed. . In addition, a bending moment is applied to the bolt 11 by the lock nut 2, so that the lock nut 2 and the fastening nut 2 and the bolt 1
Since 1 and 1 are firmly pressure-bonded, a good anti-loosening effect can be obtained.

[0018]

[0019]

As is apparent from the above description, according to the present invention, since the end surface of the lock nut on the contact side with the fastening nut is an inclined surface, the fastening nut is tightened to the bolt, Next, when the lock nut is screwed in, from the time when the lock nut hits the fastening nut, the clearance of the engagement portion between the lock nut and the bolt,
The lock nut is rotated while the inclined surface is tilted in the direction in which it comes into surface contact with the end surface of the fastening nut, and as a result, a bending moment acts on the bolt and a reaction force against the bending moment is generated in the bolt, so that the lock nut and fastening The nut is securely fixed to the bolt. Therefore, unlike the conventional case, it is not necessary to perform the returning and rotating operation of the fastening nut after screwing the lock nut, or the tightening operation of the lock nut in a state where the fastening nut is fixed, and such operation was neglected. As a result, no lock failure will occur.

In addition, the outer peripheral surface of the end portion of the lock nut on the inclined surface formed on the contact side with the fastening nut has a cylindrical shape, while the end surface of the fastening nut on the contact side with the lock nut surrounds the screw hole. consecutively provided a thin-walled cylindrical portion and the cylindrical portion, the distal end of the cylindrical portion of the cylindrical end portion of the inclined surface on the outer peripheral surface of the lock nut is fitted in a state of pressure contact, the the lock nut on the cylindrical portion, the bolt is rotated together with fastening nut when going by screwing the lock nut to sometimes lock nut relative to the fastening nut rotated stopped in contact with the fastening nut clamping surface Is engaged with a frictional force such that the inclined surface is relatively rotated while inclining in a direction in which the end surface of the fastening nut is in surface contact with the end surface of the fastening nut. At the tip When the lock nut is engaged with the lock nut and the lock nut is rotated, the portion of the lock nut on the protruding side of the inclined surface is crimped to the fastening nut. By the engagement in the cylindrical portion, the relative postures of both nuts are accurately regulated, and the fastening nuts rotate together, so that both nuts can rotate integrally and can be quickly screwed into the bolt. Become. Then, when the fastening nut hits the tightening surface and an axial force of the bolt more than the crimping force of both nuts is applied to the fastening nut, the rotation of the fastening nut is stopped and, in the lock nut, a thin-walled cylinder. While the tip of the part is slightly deformed, the inclined surface of the lock nut is rotated while inclining in a direction in which it makes surface contact with the end surface of the fastening nut. As a result, a bending moment acts on the bolt and a reaction force against the bending moment acts on the bolt. Occurs, and the lock nut and the fastening nut can be reliably fixed to the bolt. Therefore, both nuts can be screwed into the bolt at the same time and at high speed by a simple operation of simply rotating the lock nut, and a reliable lock can be applied.

[Brief description of drawings]

FIG. 1 is a plan view of a double lock nut according to the present invention.

FIG. 2 is an exploded view of the double lock nut.

FIG. 3 is a sectional view of the double lock nut in a disassembled state.

FIG. 4 is a sectional view of the double lock nut during tightening.

FIG. 5 is a cross-sectional view after tightening the double lock nut.

FIG. 6 is a half sectional view of a conventional double lock nut.

FIG. 7 is a diagram for explaining a defect of a conventional double lock nut.

[Explanation of symbols]

 X Double lock nut 1 Fastening nut 2 Lock nut 3,6 Screw hole 4 Cylindrical part 5 Bent part 7 Lower end part 8 Inclined surface 11 Bolt

Claims (1)

(57) [Scope of utility model registration request] 1. A double lock nut comprising a tightening nut and a lock nut, wherein an end surface of the lock nut on the contact side with the tightening nut intersects obliquely with the axis of the lock nut. At the same time, the outer peripheral surface of the end portion on the inclined surface side is formed into a cylindrical shape, while a thin-walled cylindrical portion surrounding the screw hole is continuously provided on the end surface of the fastening nut on the contact side with the lock nut, and cylindrical end portion of the inclined surface of the lock nut to the cylinder portion is, on its outer peripheral surface
Serial the tip of the cylindrical portion is fitted in a state of pressure contact, the lock nut cylindrical portion, and around the fastening nut co when going by screwing the lock nut to the bolt, the clamping surface said fastening nut The lock nut is engaged with the fastening nut by a frictional force so as to rotate relative to the fastening nut while inclining in a direction in which the inclined surface is in surface contact with the end surface of the fastening nut when the rotation is stopped. A double lock nut that is characterized.