JPH08312628A - Castle nut for detent - Google Patents

Abstract

PURPOSE: To provide a castle nut for detent in which a pin hole formed on a bolt can be enough to be one, and grooves can be simultaneously manufactured by pressing. CONSTITUTION: In a castle nut for dent constituted so that a split pin inserted through a pin hole 3 of a bolt is engaged with a groove 3 formed on one end face side of the nut 1, 10-12 pieces of grooves 3 having depth of the ratio to groove width 0.7-1.0, and extending in the radial direction are formed on the outer circumference of the one end face of the nut 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut with a groove for preventing rotation for preventing the nut from loosening with respect to a bolt.

[0002]

2. Description of the Related Art Generally, in a nut used for fastening an undercarriage part of an automobile at an important point which should never fall out, a groove extending in a radial direction is formed on one side surface of the nut and is provided on the bolt. A split pin inserted through the pin hole is engaged with a groove of a nut screwed at a predetermined position to prevent the nut from rotating.

That is, the bolt is provided with two pin holes in a cross shape, and usually six radial grooves are formed on one side surface of the nut for fastening. Therefore, when tightening the nut, select the pin hole closer to the groove of the nut from the two pin holes of the bolt,
The nut is rotated to align the holes, the split pin is inserted into the pin hole, and both ends of the split pin are engaged with the groove of the nut.

[0004]

However, in the above-mentioned one, since one of the two pin holes is used for the split pin insertion, the other pin holes are completely wasted. I have a problem. On the nut side, J
According to IS, the groove depth is 1.2 to the groove width.
Since the ratio is 1.5, and the depth of the groove is relatively large, it is difficult to manufacture it by forging, and it is necessary to cut the groove with a metal saw, which causes an increase in cost. There is.

In view of the above, the present invention provides a rotation preventing grooved nut that can form one pin hole in a bolt and can also form a groove by forging at the same time. To aim.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a grooved nut for preventing rotation, wherein a split pin inserted in a pin hole of a bolt is engaged with a groove formed on one end face side of the nut. On the outer peripheral side of one end surface of the nut, the depth of the groove width ratio is 0.7 to 1.0, and it extends in the radial direction.
It is characterized in that 12 grooves are formed.

[0007]

[Operation] By engaging the split pin inserted in the pin hole of the bolt with the groove selected from the above grooved nuts,
The nut can be prevented from rotating, and the nut can be securely prevented from loosening. Moreover, when the number of grooves is 12, the maximum hole alignment range for one pin hole is ± 1.
It becomes 5 °, which is the same as the conventional one, and only one pin hole of the bolt can be used, and the groove can be formed at the same time during nut forging by reducing the groove depth.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a partially longitudinal side view of the nut with groove for rotation prevention according to the present invention. A cylindrical projection 2 is integrally formed on one end surface of the nut 1, and the cylindrical projection 2 is formed. Twelve grooves 3 extending in the radial direction are formed in the.

The groove bottom shape of each groove 3 is round,
The depth of each groove 3 is relatively shallow so that the ratio to the groove width is 0.7 to 10.

FIGS. 3 and 4 are views showing a state in which the nut 1 is screwed onto a bolt 4, and the bolt 4 is provided with one pin hole 5 extending in the diametrical direction. Any of the grooves 3 of the nut 1 is aligned with the hole 5, the split pin 6 is inserted through the groove 3 and the pin hole 5, and the tip of the split pin 6 is bent to prevent the nut 1 from rotating. .

By the way, in the conventional grooved nut,
In order to design the shaft of the cotter pin so that it fits within the groove of the nut, and considering the cumulative tolerance of the nut and the object to be fastened, the groove depth should be 1.2 to 1.5 as the ratio to the groove width. Is formed.

However, the width C of the head of the general split pin 6 is C = 2d, where d is the diameter of the shaft of the split pin 6, and the head has a width of 0.5d from the shaft of the split pin. However, since the tip end side is bent up and down, the part bent to the nut side is not included in the groove 3
Can be fully engaged with.

Not only when the shaft portion of the split pin 6 fits into the groove of the nut 1 so as to contact the bottom portion of the groove 3 as shown in FIG. 3, but also as shown in FIG. Even when the shaft portion of the above is slightly fit in the groove 3, the nut rotation preventing effect is sufficiently produced.

Therefore, considering the cumulative tolerance of related parts, from the position where the shaft portion of the split pin is completely set in the groove,
It suffices if the groove has a groove depth of a distance up to a position where the shaft portion is slightly fitted in the groove.
The ratio to the groove width may be about 0.7 to 1.0, and at the time of nut forging, this groove portion can be simultaneously formed by forging.

On the other hand, in the case where the conventional nut having 6 grooves has only one pin hole for the bolt, in order to insert the split pin after tightening with an appropriate torque, the hole alignment of up to ± 30 ° is required. However, if the bolt has only one pin hole for the purpose of economic effect, if the number of nut grooves is 12, the maximum hole alignment range is ± 15 °. Is the same as

Although the number of grooves is 12 in the above embodiment, it may be 10 if the diameter is small.

[0018]

As described above, according to the present invention, the nut is provided with ten to twelve grooves for preventing rotation, and only one pin hole is provided in the bolt, and the same effect as the conventional one can be obtained. And the ratio of the groove depth to the groove width is 0.7.
Since the groove is relatively shallow so as to be 1.0, the groove can be formed at the same time when the nut is pressed, and the cost can be reduced. Further, when the groove bottom shape is round, forging can be further facilitated.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional side view of a nut with a groove for preventing rotation of the present invention.

FIG. 2 is a plan view of the nut with groove for rotation prevention of the present invention.

FIG. 3 is a view showing an example of a state in which a split pin attached to a bolt is engaged with a groove of a nut.

FIG. 4 is a diagram showing another example of a state in which a split pin attached to a bolt is engaged with a groove of a nut.

[Explanation of symbols]

 1 Nut 2 Cylindrical protrusion 3 Groove 4 Bolt 5 Pin hole 6 Split pin

Claims (3)

[Claims] 1. A rotation-preventing grooved nut in which a split pin inserted into a pin hole of a bolt is engaged with a groove formed on one end face side of the nut, wherein a nut on the outer peripheral side of one end face of the nut is provided. A rotation-preventing grooved nut having a depth of 0.7 to 1.0 with respect to the groove width and formed with 10 to 12 grooves extending in the radial direction. 2. The groove bottom shape is round,
The grooved nut for locking according to claim 1. 3. The rotation-preventing grooved nut according to claim 1, wherein the groove width is about 1.1 times the diameter d of the split pin.