JPH0638171Y2 - Bolt rotation stop structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a bolt rotation preventing structure that is generated when a tightening object such as a structural material is tightened with a bolt to connect or fix the same.

(Prior Art) For example, as shown in FIG. 4, when connecting an object 2 to be fastened to a fixed object 1, a screw hole 3 is formed in the fixed object 1, and a bolt is inserted from a recess 4 of the object 2 to be fastened. It is common to insert 5 and screw the bolt 5 into the screw hole 3 for connection. When the head 5a of the bolt 5 with a hole is dropped into the recess 4 of the object to be fastened and used, the head 5a of the bolt 5 serves as a rotation stopper to prevent the bolt 5 from loosening and turning. The upper end of the recess 4 is fixed by welding 6.

Further, for example, as described in Japanese Utility Model Publication No. 40-22327, a cylindrical washer is fitted into a bolt, and the upper peripheral edge of this washer is folded into a notch groove provided in a tightening plate to prevent the bolt from rotating. Devices are also known.

[Problems to be solved by the device]

However, when the material of the bolt 5 is an alloy steel, there is a problem that cracking, deterioration and strength reduction due to welding occur. Also, in the structure in which the rotation is prevented by welding, if it becomes necessary to remove the bolt 5 for maintenance, the welding 6
The problem was that the removed portion had to be cut off, the bolt 5 could not be reused, and a lot of labor was required for the cutting work.

On the other hand, the bolt detent device disclosed in Japanese Utility Model Publication No. 40-22327 has a notch groove formed in the tightening plate that has a chamfered shape in which a corner of the tightening plate is shaved off. Since the folding part is also only temporary temporary stop, there is a problem that the return resistance of the folding part, that is, the anti-rotation force is small.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a bolt detent structure that can be easily removed during bolt removal during maintenance or the like.

[Constitution of device]

(Means for Solving the Problem) The present invention forms a recess into which a head of a bolt is inserted when a bolt is screwed into an upper portion of a screw hole formed in an object to be fastened, and this recess Form a vertical groove on the side of the
A vertical groove is also formed on the head of the bolt, and with the bolt screwed into the object to be fastened, a detent ring is inserted between the side of the head of the bolt and the inner surface of the recess. Insert the pin into the groove and press a part of the side surface of the anti-rotation ring to caulk, and fix the pin in the vertical groove to fix the object to be fastened, the anti-rotation ring and the head of the bolt. Is integrally fixed.

(Operation) When the bolt tries to turn to the loose side, a compression force acts on the detent ring that is crimped by pressing it with the vertical groove of the tightened object recess and the vertical groove of the bolt head. Prevent the bolt from trying to rotate. The crimping portion of the ring prevents the swaging deformation of the swivel ring swaged by the warp groove of the object to be fastened and the warp groove of the bolt head from returning and further strengthens the swivel stop effect. When it becomes necessary to remove the bolt during maintenance or the like, the detent mechanism can be released by expanding the caulked pressing portion and removing the pin and the detent ring to restore the original state.

(Embodiment) An embodiment of a bolt retaining structure according to the present invention will be described with reference to FIGS. 1 to 3.

1 is a vertical cross-sectional view partially showing a side view of a state in which a bolt is screwed into an object to be fastened to prevent it from rotating, and FIG.
FIG. 3 is a top view of the figure, and FIG. 3 is a perspective view of the detent ring in FIG.

In FIG. 1, reference numeral 1 is a fixed object having a screw hole 3 and may be a tightened object in some cases, but here it is referred to as a fixed object for convenience of description. The object to be fastened 2 is placed on the fixed object 1, the wrench is inserted into the wrench insertion hexagonal hole 13 formed in the head 5a of the bolt 5, and the bolt 5 is screwed in to integrally fix the fixed body. It is formed. A recess 4 into which the head 5a of the bolt 5 is dropped and inserted is formed on the screw hole 3 of the object 2 to be fastened. A semicircular vertical groove 7 is formed on the inner surface of this recess. A semicircular vertical groove 8 is also formed on the side surface of the head 5a of the bolt 5. The vertical grooves 7 and 8 of the both are just when the bolt 5 is screwed into the screw hole 3 of the fixed object 1,
The grooves 7 and 8 are provided at positions such that a circular groove is formed. Then, the object to be fastened 2 is placed on the fixed object 1, and the bolt 5 is inserted and screwed. Head 4a of recess 4 and bolt 5
Since it is formed in advance so that a slight gap 9 is formed between the and, a detent ring 11 having a slot 10 as shown in FIG. 3 is inserted into the gap 9. Then, the small cylindrical pin 12 is tapped and pressed from the outside of the ring 11 into the circular groove described above, and the side surface of the ring 11 is fixed to the bolt head 5a.
Attached to the vertical groove 8 and the vertical groove 7 of the recess 4 to be fastened
And the detent ring 11 and the bolt head 5a are integrally fixed.

Next, the operation of the bolt detent structure having the above structure will be described.

When the bolt 5 tries to rotate toward the loosening side, a compressive force acts on the detent ring 11 crimped into the groove 7 in the recess 4 of the object to be fastened 2 and the bolt head groove 8 to rotate the bolt 5. To prevent The pin 12 prevents the swaging deformation of the swivel stop ring 11 swaged by the groove 7 of the object to be fastened and the bolt head groove 8 from returning and further strengthens the swivel stop effect. When it becomes necessary to remove the bolt during maintenance or the like, the pin 12 is pulled out, and then the detent ring 11 is pulled out, whereby the detent mechanism can be easily released.

The present invention is not limited to the above-mentioned embodiment, and a cylindrical anti-rotation ring without a slot can be used instead of the slot with a slot.

[Effect of device]

According to the present invention, since the bolt can be prevented from rotating by the action of the vertical groove, the detent ring and the pin without using welding, the detent of the alloy steel bolt does not cause damage or deterioration of the bolt. Therefore, the reliability of the tightened portion can be secured. Further, when it is necessary to remove the bolt during maintenance or the like, the detent mechanism can be easily released and the bolt can be reused because it is not damaged.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a partial side view of an embodiment of a detent structure for bolts according to the present invention, FIG. 2 is a top view of FIG. 1, and FIG. 3 is a detent ring in FIG. FIG. 4 is a vertical cross-sectional view showing a part of a conventional bolt rotation preventing structure on a side surface. 1 ... Fixed object, 2 ... Tightened object, 3 ... Screw hole, 4 ... Recess, 5 ... Bolt, 6 ... Welding, 7 ... Vertical groove in recess, 8 ... Bolt head Vertical groove, 9 …… Gap, 10 …… Slitting, 11 …… Rotating ring, 12 …… Pin, 13 …… Hexagonal hole.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. When a bolt is screwed into an upper portion of a screw hole formed in an object to be tightened, a recess is formed into which the head of the bolt is inserted, and a vertical groove is formed on a side surface of the recess. In addition to forming it, form a vertical groove in the head of the bolt, and insert the rotation stop ring between the side surface of the head of the bolt and the inner surface of the recess while the bolt is screwed into the object to be tightened. , Inserting pins into the both vertical grooves and pressing a part of the side surface of the anti-rotation ring to caulk, fixing the pins in the vertical grooves to fix the object to be fastened, anti-rotation ring and bolt A bolt rotation preventing structure characterized by being integrally fixed to the head of the bolt.