JP2554969Y2 - Cam washer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cam washer, and more particularly, to a cam washer for locking a bolt or a nut after fastening an object to be fastened by a bolt and a nut.

[0002]

2. Description of the Related Art When an object to be fastened is fastened by bolts or nuts, if a loosening occurs due to vibration or other external force after the fastening, a predetermined fastening axial force is lost and a fastening failure occurs. For this reason, the fastening is achieved by a combination of a nut having a cam portion having a downward slope in the screw tightening direction and projecting in an annular direction, and a cam washer having a cam portion on the upper surface for engaging the cam portion on the nut side. It is thought to do.

[0003] According to such a combination structure, if the inclination angle of the cam portion of the set larger than the lead angle of the screw portion of the nut, the fastened object by tightening the nut on the bolt the In the fastened state, even if the nut attempts to rotate in the loosening direction due to subsequent vibration or other external force, the rotation must be accompanied by the movement of the nut side cam section moving over the cam section of the cam washer and overcoming it. Therefore, the rotation is prevented and loosening does not occur.

[0004]

By the way, when the fastening is performed using the nut and the cam washer, once the fastening is performed, the nut is rotated in the loosening direction with respect to the bolt for the same reason as the above-described loosening preventing action. However, it is impossible to disassemble the fastening object, so that the range of use is limited.

[0005] Accordingly, the present invention is, while preventing the slack, it can be released easily entered into at the time of need, and to perform the loosening
Cams are formed on bolts and nuts as bolts and nuts
It is possible to use a normal shape that has not been
It is an object to provide a cam washer that can be easily handled .

[0006]

Means for Solving the Problems That is, the present invention provides a
The first washer in contact with the bolt or nut, and the first washer
A cam comprising a second washer interposed between the workpiece and a workpiece
A washer, wherein an outer peripheral portion of the second washer has a polygonal shape.
With a non-slip on one side and an
A recess into which the first washer is rotatably fitted;
A blocking portion for preventing the first washer from coming out of the recess.
While provided, the bolt of the first washer or
A non-slip is formed on the surface in contact with the nut, and a screw is
The cam section that has a downward slope in the tightening direction projects and is annular.
And on the bottom surface of the recess of the first washer.
A plurality of cam portions engaging with the cam portion of the first washer are formed in an annular direction.
Further, the inclination angles of these cam portions are
Larger than the lead angle of the threaded part of the bolt or nut
Characterized by the fact that

[0007]

According to the above arrangement, the bolt or the nut is covered with the nut.
Both the first and second washers interposed between the fasteners
The inclination angle of the cam part of the bolt or nut is
Since the lead angle of the screw is larger than
Or, if the nut is fastened,
First washer and second washer interposed between the socket and the workpiece
The bolts due to vibrations etc.
Or the first seat can be prevented from loosening.
A bolt that prevents loosening by using gold and a second washer
A cam is formed on the bolt or nut.
It is possible to use a normal shape which is not used. Also on
Since the outer peripheral portion of the second washer has a polygonal shape,
After tightening as shown in the illustration, grasp the second washer with a torque wrench, etc.
, The first washer rotates together, and the first washer
Both bolts and nuts are used to prevent slippage on gold.
Loosen the bolts or nuts
Can be understood.

[0008] In particular, the first washer is more than the second washer.
The second washer is fitted into a recess formed in the second washer, and
Both washers are separated because the escape is more blocked
Between the bolt or nut and the workpiece without
Can be easily set.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 5 show a cam washer according to the present embodiment, in which a nut 10 having no cam portion is prevented from loosening and can be disassembled after fastening.

That is, the cam washer of this embodiment comprises two washers 11 and 12, a first and a second washer. The first washer 11 has a plurality of protrusion-shaped slip stoppers 13 to 13 formed on an upper surface with which the nut 10 contacts, and a plurality of cam portions 14 to 14 having a downward slope in the screw tightening direction protrude from the lower surface to form an annular direction. Formed. On the other hand, the outer peripheral portion 12A of the second washer 12 has a hexagonal shape, a concave portion 15 in which the first washer 11 is fitted is formed at the center of the upper surface, and the lower surface of the concave portion 15 descends in the screw tightening direction. The inclined cam portion 16 is formed in the annular direction so as to protrude by the same number as the cam portion, and protruding slip stoppers 17 to 17 are provided on the lower surface of the washer. In this case, the first and second washers 11, 12
Is set to be larger than the lead angle of the screw portion of the nut 10 at the same time, and the first washer 11 is inserted into the recess 15 of the second washer 12.
Are fitted in a state where the cam portions 14 and 16 of both washers 11 and 12 are engaged. The annular washer 18 surrounding the recess 15 of the second washer 12 with the first washer 11 fitted in this manner.
Are caulked at about three places on the upper surface of the first washer, and the first washer 11 is prevented from coming off by the blocking portion formed by the caulking portions 19 to 19 (see FIG. 1 ). The first washer 11 is rotatable in the recess 15 and is capable of slightly moving up and down. The nut 10 does not contact the annular convex portion 18 of the second washer 12.

[0012] By fastening the nut 10, as shown in FIG. 5 using such cam washer 11 on the bolt 7,
When the nut 10 attempts to rotate in the loosening direction due to vibration or other external force after completion of the fastening, the non-slip 1
Since the first washer 11 is fixed to the nut 10 by 3, the first washer 11 tries to rotate together with the nut 10.
However, this rotation is caused by the cam portion 14 on the first washer 11 side.
The second fixed to the workpiece X by the non-slip 17
It is necessary to move over the cam portion 16 of the washer 12 to get over it, and the inclination angle of each of the cam portions 14 and 16 is set to be larger than the lead angle of the screw portion 8 of the nut 10 and the bolt 7. As a result, rotation is prevented and loosening does not occur.

The outer peripheral portion 12A of the second washer 12 described above.
Are hexagonal, so that the nut 10
Can be rotated by fitting a wrench to the second washer 12 from a state where is fastened to the bolt 7. Therefore, if the second washer 12 is rotated in a direction to loosen the nut 10 against the non-slip 17, the force is applied to the cam portion 1 in the engaged state.
Since the nut 10 acts on the first washer 11 via the non-slip 13 through the nuts 4 and 16, the nut 10 rotates together with the both washers 11 and 12, and the nut 10 is loosened. Thereafter, the nut 10 can be rotated and removed from the bolt 7. Therefore, the bolt 7 and the nut 10 can be disassembled, and the objects X, X can be disassembled, even if the nut itself cannot be directly rotated after fastening because the cam engagement structure is employed for the purpose of preventing loosening.

[0014] In addition, it will be to use two washers, the second
A state in which the first washer 11 is prevented from coming out of the washer 12 by the swaged portion 19 formed in the second washer 12 .
As in the case where both washers 11 and 12 are separated from each other, it is possible to save time and effort for combining when using and to eliminate mistakes in the combination.
It can also be avoided occurrence of a situation such as the loss of one of the washer.

As described above, the bolts and nuts are fastened by rotating these bolts and nuts with a torque wrench or the like so as to obtain a predetermined tightening axial force. Even if it is rotated, it is not always possible to obtain a predetermined tightening axial force due to the presence of screws, bearing dents, rust, oil adhesion, etc., and it is difficult to judge it, and the temporary tightening state of multiple bolts etc. There was a problem that the tightening axial force was not constant due to variations in the tightening rotation angle from the time of completion to the completion of fastening.

For this reason, in the present embodiment, a concave step portion 20 is formed by notching at the outer peripheral corner on the seating surface side of the nut 10, and a C-shaped ring 21 having an opening 21A in the concave step portion 20 is partially formed. Engage in a state of protruding outward. In this case, the C-shaped ring 21 is made of, for example, a metal body (which may be a resin body) having elasticity capable of expanding and contracting in the diametrical direction. ,
It is configured to rotate integrally with the nut 10.

The second washer 12 has a recess 15
The annular convex portion 18 surrounding the C-shaped ring 21 is located outside the C-shaped ring 21. A temporary fastening position display mark (snag point or seating point) 22 and a fastening completion position display mark 23 are provided on the upper surface of the annular convex portion 18. Are provided at a predetermined rotation angle. The marks 22 and 23 are formed by applying a paint or engraving the washer 12.

Such a nut 10 and cam washers 11, 1
According to No. 2, when the nut 10 is screwed into the bolt 7 with a wrench, the screwing is advanced, the second washer 12 is pressed against the surface of the workpiece, and the non-slip 17 bites into the workpiece X, thereby reducing the screwing resistance of the nut 10. Is increased, the screwing is once stopped, the diameter of the C-shaped ring 21 is enlarged using the opening 21A, and the C-ring 21 is independently rotated with respect to the nut 10, and the opening 21A is temporarily tightened.
2, the nut 10 can be tightened with the wrench until the opening 21A matches the fastening completion position indicating mark 23.

Therefore, the nut 10 and the cam washer 1
According to Nos. 1 and 12, the angle between the temporary fastening position indicating mark 22 and the fastening completed position indicating mark 23 is set so that a predetermined tightening axial force is obtained when the nut 10 is tightened from the temporarily tightened state. In this case, the predetermined tightening axial force can be easily and reliably obtained, and since the tightening rotation angle from the temporary tightening state to the completion of the fastening is constant, the variation in the tightening rotation angle does not occur. .

In the above embodiment, the cam washer used on the nut side has been described. However, the present invention can of course be applied to a cam washer for a bolt. In addition, the above C
The shaped ring can be a complete annular elastic ring,
In that case, a rotation angle display mark corresponding to the opening 21A is formed on the elastic ring.

[0021]

As evidenced by [devise effects above described, the
According to the invention, the bolt or nut is fastened
Then, it is interposed between the bolt or nut and the workpiece
The engagement of the cam portions of both the first washer and the second washer
To prevent bolts or nuts from loosening due to vibration, etc.
And by using these first and second washers.
Bolts and nuts to prevent loosening,
Use nuts of normal shape without cams.
The outer washer of the second washer
Since it is square, after fastening as described above,
If you grab the second washer with a wrench and rotate it, the first
The anti-slip provided with the first washer, with which the gold rotates.
The bolts or nuts will also go around
Can be disassembled by loosening bolts or nuts.
It is possible to disassemble knots and reuse bolts or nuts
Become.

In particular, the first washer is provided for the entire second seat.
The second washer is fitted into a recess formed in the second washer, and
Both washers are separated because the escape is more blocked
The combination hand when using it, as if
It is possible to save time and eliminate mistakes
And the loss of one washer
can avoid.

[Brief description of the drawings]

FIG. 1 is a plan view of a cam washer according to an embodiment of the present invention.
It is.

FIG. 2 is an exploded view of the cam washer.

FIG. 3 is a partially cutaway side view of the cam washer.

FIG. 4 is a plan view of the used state of the cam washer.

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

[Description of Signs] 10 nut 11 first washer 12 second washer 13,17 non-slip 14,16 cam portion 15 recess 19 blocking portion (caulking portion) X workpiece

Claims (1)

(57) [Scope of request for utility model registration] 1. A first washer in contact with a bolt or a nut.
And a second clamped between the first washer and the workpiece.
A cam washer comprising a washer, and an outer periphery of the second washer.
The part has a polygonal shape and a non-slip is formed on one side.
And the first washer is rotatably fitted to the other surface.
A recess is formed and the first washer comes out of the recess.
While the first washer is provided.
Non-slip formed on the surface in contact with the above bolts or nuts
And the cam surface has a downward slope on the opposite side in the screw tightening direction.
Are formed in a protruding annular direction, and the first
A plurality of cams of the first washer are engaged with the bottom of the washer recess.
Cam portions are provided in the annular direction, and further, these cam portions
Of the screw part of the bolt or nut
A cam characterized in that it is larger than the lead angle.
Washer.