JP2005256993A - Releasing device of detachment preventing tool for fastening part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a releasing device which easily and accurately deforms an engagement ring elastically in the diameter-reducing direction over the whole periphery of the engagement ring. <P>SOLUTION: The releasing device comprises: a main cylinder 9 fitted on the outer periphery of a protective cap 5; a subcylinder 10 fitted on the outer periphery of the main cylinder 9; a plurality of push levers 13 each fitted in a radially-extending expanding slot 11 of the main cylinder 9 so as to oscillatingly rotate around a pivot 12 at the proximal end portion; push projections 15 each provided on an inner surface of the distal end portion of the push lever 13 so as to advance into an engagement groove 6 from a side hole 14 of the protective cap 5; and drive cam surfaces 16 formed on an inner surface of the subcylinder 10 so as to oscillatingly rotate the push levers 13 in the centripetal direction when the subcylinder 10 rotates with respect to the main cylinder 9. When the push levers 13 oscillatingly rotate in the centripetal direction, the engagement ring 7 is pressed in the diameter-reducing direction by the push projections 15, so that the outer peripheral portion of the engagement ring 7 is forced out of the engagement groove 6. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a release device applied to a tool for preventing removal of a fastening portion by screwing of a bolt and a nut.

Fastening by tightening bolts and nuts is easy to increase or decrease the fastening force by adjusting the tightening torque, etc., and the fastening force can be readjusted as necessary even after the fastening is complete. Used as an effective means of mechanical fixation.
However, since fastening by screwing can be easily loosened with a commercially available general tool such as a spanner, there have recently been reported cases in which the fastening points of power transmission towers and railway tracks are illegally removed.

In order to prevent illegal removal of fastening by screwing, insert a holder between the bolt head and the body to be fastened or between the nut and the body to be fastened, and put a protective cap on the bolt head and the holder or nut and holder to protect Fastening part removal prevention by fitting the outer peripheral portion of the C-shaped locking ring into the locking groove on the inner peripheral surface of the cap and fitting the inner peripheral portion of the locking ring into the receiving groove on the outer peripheral surface of the holder A tool has been proposed (Patent Document 1).

To release the fastener removal prevention tool, insert a pin from the side of the protective cap, press the outer peripheral surface of the locking ring with the tip of the pin, elastically deform the locking ring in the reduced diameter direction, This is done by pushing the outer peripheral part out of the locking groove of the protective cap.

For such a release operation to be completed successfully, the locking ring is uniformly deformed in the diameter reducing direction at each part of the entire circumference, and the outer peripheral portion of the locking ring is locked at the locking groove at each part of the entire circumference. In order to do so, it is necessary to form a plurality of pin insertion holes in the peripheral surface of the protective cap and to push the plurality of pins inserted into them simultaneously and at the same distance. As a matter of fact, it is impossible to do this accurately by hand.
Japanese Patent Laid-Open No. 2003-113829

The subject of this invention is providing the cancellation | release apparatus which can perform the elastic deformation of the diameter reduction direction over the perimeter of a locking ring simply and correctly.

The releasing device according to the first aspect of the present invention includes a bolt and nut screwed together by inserting a holder 4 between the head of the bolt 1 and the fastened body 2 or between the nut 3 and the fastened body 2. Cover the head and the holder 4 or the nut 3 and the holder 4 with the protective cap 5, and fit the outer peripheral portion of the C-shaped locking ring 7 into the locking groove 6 on the inner peripheral surface of the protective cap 5. It is a release device applied to a fastening part removal prevention tool adapted to fit the inner peripheral part of the locking ring 7 into the receiving groove 8 of the surface,
The main cylinder 9 fitted to the outside of the protective cap 5, the sub cylinder 10 fitted to the outside of the main cylinder 9, and the radial split groove 11 of the main cylinder 9 are fitted to the pivot of the base end portion. A plurality of push levers 13 that oscillate and rotate 12, a push protrusion 15 that is provided on the inner surface of the tip of the push lever 13 and that can enter the locking groove 6 from the side hole 14 of the protective cap 5, and the sub cylinder 10 It is formed on the inner surface, and when the sub cylinder 10 rotates with respect to the main cylinder 9, it comprises a drive cam surface 16 that swings and rotates the push lever 13 in the centripetal direction, and the push lever 13 swings and rotates in the centripetal direction. At this time, the locking ring 7 is pressed in the diameter-reducing direction by the push protrusion 15 so that the outer peripheral portion of the locking ring 7 is pushed out from the locking groove 6.

The main feature of the invention of claim 2 is that, in addition to the structure of the invention of claim 1, a spring member 17 is inserted between the main lever 9 and the push lever 9, and the spring member 17 causes the push lever 9 to move in the centrifugal direction. This is because the push protrusion 15 is held at the standby position where it does not contact the outer peripheral edge of the protective cap 5 by being biased by rotation.

  The main feature of the invention of claim 3 is that, in addition to the structure of the invention of claim 1 or claim 2, the first operation bar 18 projects radially from the side surface of the main cylinder 9, and The second operation bar 19 protrudes in the radial direction on the side surface, and the operation bars 18 and 19 are pushed to rotate the sub cylinder 10 relative to the main cylinder 9.

In the release device according to the first aspect of the present invention, the main cylinder 9 is fitted into the protective cap 5 and the side hole 14 of the protective cap 5 and the push protrusion 15 of the push lever 13 are aligned, and then the sub cylinder 10 is moved. By rotating with respect to the main cylinder 9, the push lever 13 swings and rotates in the centripetal direction by the pressing action of the drive cam surface 16, and the push protrusion 15 presses the outer peripheral surface of the locking ring 7. No matter how many levers 13 are provided along the circumference of the main cylinder 9, the push levers 13 simultaneously swing and rotate in the centripetal direction, and the push protrusions 15 are formed at each part of the entire circumference of the locking ring 7. At the same time, the locking ring 7 is pressed by an equal distance, and the outer peripheral portion of the locking ring 7 is pushed out from the locking groove 6 at a stretch.
Since the locking ring 7 is not re-engaged with the locking groove 6 by keeping the sub-cylinder in the initial rotational position, the protective cap can be obtained by pulling the main cylinder 9 and the sub-cylinder 10 as they are. 5 is pulled out of the laminated body of the head of the bolt 1 and the holder 4 or the laminated body of the nut 3 and the holder 4 together with the main cylinder 9.
That is, according to the first aspect of the invention, the removal operation of the protective cap 5 can be performed easily and accurately.

In the invention of claim 2, the spring member 17 inserted between the main lever 9 and the push lever 9 always urges the push lever 9 to rotate in the centrifugal direction so that the push protrusion 15 contacts the outer peripheral edge of the protective cap 5. Since the main cylinder 9 is fitted to the protective cap 5, the push protrusion 15 does not interfere and the fitting operation can be performed smoothly.

In the third aspect of the invention, the first operation bar 18 protrudes in the radial direction on the side surface of the main cylinder 9, while the second operation bar 19 protrudes in the radial direction on the side surface of the sub cylinder 10. By pushing 18 and 19 toward each other, the sub-cylinder 10 can be rotated with a light force with respect to the main cylinder 9 and can be held at the original rotational position. The push-out operation of the lock ring 7 from the lock groove 6 and the extraction operation of the protective cap 5 can be performed more easily and accurately.

In order to elastically deform the locking ring 7 uniformly in the diameter-reducing direction at each part of the entire circumference, it is preferable to equip a plurality of, for example, four push levers 13 at equal angular intervals. The push protrusion 15 can be formed integrally with the push lever 13, but for the convenience of replacement due to wear deformation during use, the push protrusion 15 is formed separately from the push lever 13, and the pin-shaped push protrusion 15 is formed as a push lever. It is preferable to attach to 13 front-end | tip parts.

The locking ring 7 is made of an elastic metal material in an annular shape, and is separated in the radial direction at a part of the circumference in order to enable elastic deformation in the reduced diameter direction. The side surface of the metal holder 4 is formed in a tapered shape having a small diameter on the nut 3 side and a large diameter on the tightened body 2 side. The inner periphery of the opening tip of the metal protective cap 5 is formed in a tapered surface so as to receive the unloaded locking ring 7.

After the two fastened bodies 2, 2 are fastened by screwing the bolt 1 and the nut 3, the locking ring 7 is applied to the opening tip of the protective cap 5, and the protective cap 5 is moved in the axial direction of the nut 3. When the top of the protective cap 5 is hit or pressed with an appropriate tool in the final stage, the locking ring 7 is pressed against the tapered side surface of the holder 4 and elastically deformed in the diameter increasing direction, and the outer periphery of the locking ring 7 is The portion fits into the locking groove 6 of the protective cap 5.

At this time, the protective cap 5 surrounds the laminated body of the nut 3 and the holder 4 over the entire length, and the front end surface of the opening is in contact with the surface of the fastened body 2. Even if the protective cap 5 is grasped and rotated, the protective cap 5 only idles, and no torque is transmitted to the nut 3. As a result, removal of the fastening portion between the bolt and the nut is prevented.

The locking groove 6 of the protective cap 5 and the receiving groove 8 of the holder 4 are formed in an annular shape, and a certain margin is left between the bottom of the receiving groove 8 and the inner peripheral surface of the locking ring 7 in a steady state. Has been. This extra space is for accommodating elastic deformation of the locking ring 7 in the direction of diameter reduction.
The main cylinder 9 has a flange portion 9a at the base end and a main body portion 9b to which the sub cylinder 10 is fitted. A stopper ring 20 is fitted to the distal end side of the main body portion 9b. Four split grooves 11 are provided at equiangular intervals radially near the middle portion of the flange portion 9a and the main body portion 9b.

The spring member 17 is composed of a compression coil spring. One end of the spring member 17 is in contact with the intermediate portion bottom surface 21 of the main body 9b, and the other end of the spring member 17 is the base end notch surface of the bell crank-shaped push lever 13. 22 abuts. The pivot 12 passes through a portion that is slightly away from the proximal notch surface 22 toward the distal end. With such an arrangement, the spring member 17 urges the push lever 13 to rotate in the centrifugal direction.
The pivoting rotation of the push lever 13 in the centrifugal direction is limited by the contact of the intermediate side surface of the push lever 13 with the opening edge of the sub cylinder 10.

Four side holes 14 of the protective cap 5 are provided at equal angular intervals so as to intersect the locking groove 6. The push protrusion 15 is formed in a stepped pin shape separately from the push lever 13, is fitted into the transverse hole 23 at the tip of the push lever 13, and is fixed to the push lever 13 by a retaining ring 24.

The proximal end screw shaft portion 25 of the first operation bar 18 passes through the through hole 26 of the stopper ring 20 and is screwed into the screw hole 27 on the distal end portion side of the medium diameter portion 9b, whereby the stopper ring 20 is engaged. It is fixed to the main cylinder 9. The stopper ring 20 prevents the sub cylinder 10 from coming out of the main body portion 9 b of the main cylinder 9.

The screw shaft portion 28 of the second operation bar 19 is screwed into the screw hole 29 of the sub cylinder 10. The outer peripheral surfaces of the main portions of the operation bars 18 and 19 are knurled to prevent slipping. The sub cylinder 10 rotates with respect to the main cylinder 9 by gripping the operation bars 18 and 19 so as to attract each other, and the plurality of push levers 13 are driven. In order to reduce by the lever principle, the lengths of the operation bars 18 and 19 are set longer than a certain value.

In a steady state, the push lever 13 enters the recess 30 facing the split groove 11 of the main cylinder 9, and the drive cam surface 16 is formed in an inclined shape on the inner bottom surface of the recess 30.
In order to enable the operation bars 18 and 19 to be attached at optimum positions and directions corresponding to the situation and positional relationship of the fastening portion in the fastened body 2, the through hole 26, screw hole 27, or screw hole 29. Can be provided.

It is a front view of the cancellation | release apparatus which concerns on one Example of this invention. It is a rear view of the cancellation | release apparatus of FIG. It is a left view of the cancellation | release apparatus of FIG. It is a right view of the cancellation | release apparatus of FIG. It is a top view of the cancellation | release apparatus of FIG. It is a bottom view of the cancellation | release apparatus of FIG. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is sectional drawing which shows the use condition of the cancellation | release apparatus of FIG.

Explanation of symbols

1 Bolt 2 Fastened object 3 Nut 4 Holder 5 Protective cap 6 Locking groove 7 Locking ring 8 Receiving groove 9 Main cylinder 10 Sub cylinder 11 Split groove 12 Axle 13 Push lever 14 Side hole 15 Push protrusion 16 Drive cam surface 17 Spring Member 18 First operation bar 19 Second operation bar

Claims (3)

In the fastening part by screwing of the bolt and nut in which the holder 4 is inserted between the head of the bolt 1 and the fastened body 2 or between the nut 3 and the fastened body 2, the head of the bolt 1 and the holder 4 or the nut 3 and the holder 4, the protective cap 5 is covered, the outer peripheral portion of the C-shaped locking ring 7 is fitted into the locking groove 6 on the inner peripheral surface of the protective cap 5, and the locking ring 7 is inserted into the receiving groove 8 on the outer peripheral surface of the holder 4. It is a release device applied to a fastening part removal prevention tool adapted to fit the inner peripheral part of
The main cylinder 9 fitted to the outside of the protective cap 5, the sub cylinder 10 fitted to the outside of the main cylinder 9, and the radial split groove 11 of the main cylinder 9 are fitted to the pivot of the base end portion. A plurality of push levers 13 that oscillate and rotate 12, a push protrusion 15 that is provided on the inner surface of the tip of the push lever 13 and that can enter the locking groove 6 from the side hole 14 of the protective cap 5, and the sub cylinder 10 It is formed on the inner surface, and when the sub cylinder 10 rotates with respect to the main cylinder 9, it comprises a drive cam surface 16 that swings and rotates the push lever 13 in the centripetal direction, and the push lever 13 swings and rotates in the centripetal direction. At this time, the fastening ring removal preventing tool is configured such that the push ring 15 pushes the locking ring 7 in the diameter reducing direction so that the outer peripheral portion of the locking ring 7 is pushed out from the locking groove 6. Release device.   A standby position where the spring member 17 is inserted between the main lever 9 and the push lever 9 and the push lever 9 is urged to rotate in the centrifugal direction by the spring member 17 so that the push protrusion 15 does not contact the outer peripheral edge of the protective cap 5. The release device according to claim 1, wherein the release device is held by the device.   A first operation bar 18 protrudes in the radial direction on the side surface of the main cylinder 9, a second operation bar 19 protrudes in the radial direction on the side surface of the sub cylinder 10, and the operation bars 18, 19 are pushed to bring the sub cylinder 10 into the main cylinder. The release device according to claim 1, wherein the release device is rotated with respect to the release device.

Images