JP2017218724A - Closing tool for engaging hole of cover opening operation tool of manhole cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a closing tool for an engaging hole of a cover opening operation tool of a manhole cover that does not readily fall off from the manhole cover even when a screw shaft has loosened.SOLUTION: A closing tool 1 includes a body 2 inserted into an engaging hole 25, a screw shaft 3 penetrating vertically through the body and being held, a nut member 4 screwed into the screw shaft, and a key member 5 operating the screw shaft 3 by rotation. The body 2 includes a lower insertion part 6, an upper umbrella part 7 closing the engaging hole 35, and a positioning protrusion 8 for an undersurface of the umbrella part. The nut member 4 includes a tightening protrusion 9 and a reverse rotation stopper protrusion 10, and is screwed into the screw shaft 3 with prescribed frictional resistance. The tightening protrusion 9 sandwiches the manhole cover 31 with the umbrella part 7, when the nut member 4 reaches a highest position while the tightening protrusion 9 is between rotation restricting surfaces 21, 22. The nut member 4 is restrained at a lock angle position by the rotation restricting surfaces 21, 22 even when the screw shaft 3 has loosened. Thus, the tightening protrusion 9 prevents fall-off of the closing tool from the engaging hole 35.SELECTED DRAWING: Figure 7

Description

  This invention is attached to the lid of a manhole that is an entrance to a common groove or the like for laying an electric wire / cable etc. in the ground so that the opening operation tool engaging hole provided in the lid cannot be used at normal times. The present invention relates to an obturator for closing.

When opening the manhole cover for inspection and repair of underground laying pipes and the like, an opening operation tool such as a bar-shaped hand key is inserted into the engagement hole provided in the manhole cover to cause the manhole cover. As a means for preventing an unauthorized person from opening the manhole cover, a keyhole blind plug device for a manhole cover disclosed in Patent Document 1 is known.
This device includes a main body, a screw shaft, and a tightening nut. On the back surface of the disk portion at the top of the main body, positioning protrusions that are fitted into the positioning recesses on the upper surface portion of the manhole cover are provided. The lower part of the main body is cylindrical and is inserted into the keyhole of the manhole cover. The main body is provided with a large-diameter shaft hole and a small-diameter shaft hole that communicate from the upper part of the central part to the lower part. The cylindrical portion of the main body is provided with a split groove having a forward rotation restricting surface and a reverse rotation restricting surface facing each other. The upper part of the screw shaft is received in the large-diameter shaft hole of the main body so as to be relatively rotatable. The upper end of the screw shaft is provided with a passive end portion that engages and disengages the driving end portion of the operation handle. On the lower side of the passive end, a retaining flange having a larger diameter than the small diameter shaft hole is provided. A male screw rod fitted into the small diameter shaft hole is provided on the lower side of the retaining flange. The tightening nut is screwed onto the male screw rod of the screw shaft. On the upper part of the tightening nut, a fixing claw that can pass through the escape hole of the key hole projects. The fixing claw contacts and separates from the lower surface of the manhole cover. When the screw shaft is rotated forward, the tightening nut rotates together with the screw shaft until the fixing claw contacts the regulating surface during forward rotation of the split groove. When the rotation is reversed, the fixing claw rotates together with the screw shaft until it comes into contact with the regulating surface at the time of reverse rotation of the split groove, and after the contact, the fixing claw descends relatively along the screw shaft. Insert the lower part of the device into the keyhole of the manhole cover, engage the special operation handle with the upper end of the screw shaft, and rotate it forward to relatively raise the tightening nut and contact the lower surface of the manhole cover Then, the device is prevented from coming off from the keyhole. If the screw shaft is rotated in the reverse direction, the nut can be lowered and the apparatus can be rotated. Therefore, the position of the nut can be adapted to the key hole and the apparatus can be pulled out from the key hole. Without the operation handle, the screw shaft cannot be rotated in the forward or backward direction.

Japanese Patent Laid-Open No. 10-205184

In the above-mentioned conventional device, when the screw shaft is loosened by a slight reverse rotation with some external force, regardless of the operation handle, when the screw shaft is attached to the manhole, the engagement with the manhole cover is disengaged unexpectedly. The nut may rotate with the screw shaft until it comes into contact with the regulating surface during reverse rotation, and the nut may come out of the manhole.
An object of the present invention is to provide a closing tool for an opening operation tool engaging hole of a manhole cover that does not easily come out of the manhole cover even if the screw shaft is unexpectedly loosened.

Hereinafter, the present invention will be described with reference to the accompanying drawings, but the present invention is not limited thereto.
In order to solve the above problems, the obturator 1 of the present invention includes a main body 2 inserted into the engagement hole 25 of the opening operation tool of the manhole cover 31, a screw shaft 3 held by the main body 2, and a screw shaft. 3 and a key member 5 for rotating the screw shaft 3. The main body 2 is an umbrella formed integrally with the lower insertion portion 6 to be inserted into the engagement hole 35 and an upper end portion of the insertion portion 6 and closely attached to the upper surface of the manhole cover 31 so as to close the engagement hole 35 when attached. And a positioning projection 8 that projects from the lower surface of the umbrella portion 7 and engages with the engagement hole 35 when mounted. The screw shaft 3 passes through the main body 2 up and down and is held by the main body 2 so as to be rotatable about the axis. The nut member 4 includes a tightening protrusion 9 and an anti-reverse protrusion 10, and is screwed to the screw shaft 3 with a predetermined frictional resistance. With the frictional resistance, a lock angle position and a non-locking angle position are set together with the screw shaft 3. It can be rotated 90 ° forward and backward, and is prevented from coming down with respect to the screw shaft 3. The tightening protrusion 9 engages with the lower surface of the manhole cover 31 at the uppermost position on the screw shaft 3 at the lock angle position, and protrudes in the direction orthogonal to the axis so as to pass through the engagement hole 35 at the lock angle position. The reverse rotation stop protrusion 10 protrudes to the opposite side of the tightening protrusion 9. The key member 5 includes a unique engagement portion 12 that engages with the upper end of the screw shaft 3, and the screw shaft 3 can be rotated by engaging the unique engagement portion 12 with the screw shaft 3. The insertion portion 6 of the main body 2 includes an upper cylindrical portion 16 and a pair of long and short regulating legs 17 and 18 extending downward continuously from the cylindrical portion 16. The head portion 19 of the screw shaft 3 includes a corresponding engagement portion 13 that engages with the specific engagement portion 12 of the key member 5 at the upper end portion. The pair of long and short restricting legs 17 and 18 are provided with rotation restricting surfaces 21 and 22 that face each other in a certain upper and lower range and restrain the tightening protrusion 9 of the nut member 4 at the lock angle position between both surfaces. The long restricting leg 17 further continues to the lower side of the rotation restricting surface 21, and a forward rotation restricting surface 23 that restrains the nut member 4 at the lock angle position by contacting the tightening protrusion 9 of the nut member 4 that normally rotates. And a reverse rotation restricting surface 24 for holding the nut member 4 at a non-locking angular position by contacting the reverse rotation protruding protrusion 10 of the nut member 4 rotating 90 ° away from the normal rotation restricting surface 23. To do. The nut member 4 rotating together with the forward rotation of the screw shaft 3 is constrained to the lock angle position by the forward rotation restricting surface 23 of the long restricting leg 17, and the nut member 4 is rotated at the lock angle position by further forward rotation of the screw shaft 3. The fastening protrusions 9 are configured to be brought into contact with the lower surface of the manhole cover 31 by being raised to the uppermost position between the restraining surfaces 21 and 22.

  In the obturator 1 of the present invention, the nut member 4 rises between the rotation restricting surfaces 21 and 22 at the lock angle position to the uppermost position, that is, a position where the nut member 4 comes into contact with the lower surface of the manhole cover 31. , 22, even if the screw shaft 3 is slightly loosened, the nut member 4 does not rotate, and therefore there is no risk of inadvertent removal from the engagement hole 35.

It is a front view of the obturator which concerns on this invention, (A) shows the state which has a nut member in the lowest position in a non-locking angle position, (B) shows the state which exists in a locking angle position and exists in an up-down intermediate position. The It is a right view of the obturator of FIG. It is a top view of the obturator in which a nut member exists in a lock angle position. It is a bottom view of the obturator of FIG. 1, (A) shows the state which has a nut member in a non-locking angle position, (B) shows the state which exists in a locking angle position. It is VV sectional drawing in FIG. It is a top view of a part of manhole cover which mounts the obturator of FIG. 1, (A) shows the state after mounting | wearing, (B) before mounting | wearing an obturator. It is a front view of the obturator of FIG. 1, (A) is before fixation at the time of insertion to a lid | cover, (B) is in the process of raising a nut member, (C) shows the state after fixation.

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 6 (A), the manhole cover 31 to which the obturator 1 according to the present invention is attached has a substantially semicircular arc-shaped cutout portion 32 formed on the peripheral portion thereof, an inner periphery 34 of the manhole frame body 33, and A substantially meniscus-shaped engagement hole 35 formed between the two. The engagement hole 35 is used to pry up the manhole cover 31 by inserting a lid opening operation tool (not shown) into the engagement hole 35. The obturator 1 is attached to the manhole cover 31 in order to block the engagement hole 35 of the opening operation tool so that an unauthorized person cannot remove the manhole cover 31 (FIG. 6B).

  As shown in FIGS. 1 and 2, the obturator 1 includes a main body 2 inserted into the engagement hole 35, a screw shaft 3 held by the main body 2, a nut member 4 screwed into the screw shaft 3, And a key member 5 (FIG. 5) for rotating the screw shaft 3.

  The main body 2 is formed integrally with the lower insertion portion 6 to be inserted into the engagement hole 35 (FIG. 7) and the upper end portion of the insertion portion, and the upper surface of the manhole cover 31 so as to close the engagement hole 35 when mounted. A substantially half-moon shaped umbrella portion 7 that is in close contact with the head portion, and a positioning projection 8 that projects from the lower surface of the umbrella portion 7 and engages with the engagement hole 35 when mounted.

  As shown in FIG. 4, the positioning protrusion 8 faces the inner periphery of the manhole frame 33 and moves in the center direction of the first positioning surface 25 that restricts rotation around the screw shaft 3 and the manhole cover 31. And a second positioning surface 26 to be regulated.

  As shown in FIG. 5, the screw shaft 3 includes an upper end head portion 19 and a screw portion 20 below the upper end portion, penetrates the main body 2 up and down, and is held by the main body 2 so as to be rotatable about the axis. The screw shaft 3 is rotated by the key member 5.

  The key member 5 includes a specific engagement portion 12 at the lower end, and the screw shaft 3 is rotated by engaging the specific engagement portion 12 with a corresponding engagement portion 13 formed on the head portion 19 of the screw shaft 3. can do.

  The nut member 4 includes a tightening projection piece 9 and a reverse rotation prevention projection piece 10, and is screwed onto the screw shaft 3 to be prevented from coming off downward. In the nut member 4, the lower part from the slit 11 formed at the lower end is slightly squeezed upward in the axial direction, and the screw pitch is slightly different from the upper part. Screwed together with the frictional resistance. With this frictional resistance, the nut member 4 can rotate forward and backward by 90 ° between the lock angle position shown in FIG. 4B and the non-lock angle position shown in FIG. .

  The tightening protrusion 9 protrudes in the direction orthogonal to the axis, and engages with the lower surface of the manhole cover 31 at the uppermost position (FIG. 7C) on the screw shaft 3 at the lock angle position, and engages at the non-lock angle position. It can pass through the hole 35. The reverse rotation stop protrusion 10 protrudes to the opposite side of the tightening protrusion 9.

  As shown in FIG. 5, the main body 2 includes an upper countersunk portion 14 that receives the head portion 19 of the screw shaft 3, and a lower small-diameter shaft hole portion 15 that penetrates the screw portion.

  The insertion portion 6 of the main body includes an upper cylindrical portion 16 and a pair of long and short regulating legs 17 and 18 extending downward continuously from the cylindrical portion 16.

  As shown in FIG. 4, the pair of long and short restricting legs 17 and 18 include rotation restricting surfaces 21 and 22 that face each other, and the long restricting leg 17 is a forward rotation restricting surface that continues downward from the rotation restricting surface 21. 23 and a reverse rotation restricting surface 24 on the opposite side.

  The pair of long and short restricting legs 17 and 18 restrains the tightening protrusion 9 of the nut member 4 between the rotation restraining surfaces 21 and 22 at the lock angle position. As shown in FIG. 2, the long restricting leg 17 extends longer than the short restricting leg 18, and includes a normal rotation restricting surface 23 that continues downward from the rotation restricting face 21. The forward rotation restricting surface 23 abuts the tightening protrusion 10 of the nut member 4 that rotates forward (rotation in the direction of tightening the screw) together with the screw shaft 3 to restrain the nut member 4 at the lock angle position. As shown in FIG. 4, the reverse rotation restricting surface 24 is formed on the opposite side 90 ° away from the forward rotation restricting surface 23. As shown in FIGS. 1 (A) and 4 (A), the reverse rotation restricting surface 24 brings the nut member 4 into contact with the reverse rotation protrusion 10 of the nut member 4 that rotates in reverse with the screw shaft 3. Restrain to non-locking angular position.

  That is, as shown in FIG. 7, the nut member 4 that rotates together with the forward rotation of the screw shaft 3 is constrained to the lock angle position by contacting the forward rotation restricting surface 23 of the long restricting leg 17 (see FIG. ), FIG. 4 (B)), the rotation stops. Due to further forward rotation of the screw shaft 3, relative rotation with the nut member 4 occurs, whereby the nut member 4 rises between the rotation restraining surfaces 21 and 22 at the lock angle position. When the nut member 4 is moved up to the uppermost position, the tightening protrusion 9 comes into contact with the lower surface of the manhole cover 31 and tightens the manhole cover 31 with the umbrella portion 7 of the main body (FIG. 7C).

  When the obturator 1 is attached to the manhole cover 31, the screw shaft 3 is loosened, the projecting pieces 8 and 9 are placed below the short regulating leg 18, and the reverse rotation preventing projecting piece 10 is controlled to reversely rotate the long regulating leg 17. 4A, the first positioning surface 25 is made to face the inner periphery 34 of the manhole frame 33 and the peripheral surface of the notch 32 of the manhole cover 31 at the non-locking angle position of FIG. Positioning is performed so that the second positioning surface 26 faces each other, the nut member 4, the lower portion of the screw shaft 3, and the insertion portion 6 of the main body 2 are inserted into the engagement hole 35, and the engagement hole 25 is blocked by the umbrella portion 7. . In this state, when the screw shaft 3 is rotated forward by the key member 5, the nut member 4 is rotated 90 ° together with the screw shaft 3 by the frictional resistance of the screw portion and comes into contact with the forward rotation restricting surface 23. It reaches the lock angle position. Thereby, since it is restrained in the forward rotation direction, it can no longer co-rotate with the screw shaft 3 and rises while sequentially sliding with the forward rotation restricting surface 23 and the rotation restricting surface 21, When the uppermost position is reached between 22, the tightening protrusion 9 comes into contact with the lower surface of the manhole cover 31, and the manhole cover 31 is sandwiched between the tightening protrusion 9 and the umbrella portion 7. Thereby, since the obturator 1 is fixed to the manhole cover 31 and the opening operation tool cannot be inserted into the engagement hole 35, the manhole cover 35 cannot be removed. Even if the screw shaft 3 is slightly loosened due to some external force, the nut member 4 is located between the rotation restricting surfaces 21 and 22 and is restrained at the lock angle position. Is done.

DESCRIPTION OF SYMBOLS 1 Obturator 2 Main body 3 Screw shaft 4 Nut member 5 Key member 6 Insertion part 7 Umbrella part 8 Positioning protrusion 9 Fastening protrusion 10 Reverse rotation prevention protrusion 11 Slit 12 Specific engagement part 13 Corresponding engagement part 14 Countersink part 15 Axis Hole 16 Cylindrical part 17 Long restricting leg 18 Short restricting leg 19 Head 20 Screw part 21 Rotation restricting surface 22 Rotation restricting surface 23 Forward rotation restricting surface 24 Reverse rotation restricting surface 25 First positioning surface 26 Second positioning surface 31 Manhole cover 32 Notch 33 Manhole frame 34 Inner circumference 35 Engagement hole

Claims (2)

An obturator attached to the manhole cover so as to close an engagement hole formed in the manhole cover in order to hang the opening operation tool,
A lower insertion portion that is inserted into the engagement hole at the time of mounting; an umbrella portion that is formed integrally with an upper end portion of the insertion portion and is in close contact with the upper surface of the manhole cover so as to close the engagement hole at the time of mounting; A main body provided with a positioning protrusion that protrudes from the lower surface of the umbrella portion and engages with the engagement hole when mounted;
A screw shaft penetrating up and down the main body and rotatably held around the shaft;
The manhole cover is screwed onto the screw shaft with a predetermined frictional resistance, and can rotate forward and backward by 90 ° between the lock angle position and the non-lock angle position together with the screw shaft, and the manhole cover at the uppermost position on the screw shaft at the lock angle position. A clamping protrusion protruding in the direction orthogonal to the axis so as to be able to pass through the engagement hole at a non-locking angle position, and an anti-reverse protrusion protruding to the opposite side of the clamping protrusion. A nut member that is prevented from falling downward with respect to the screw shaft;
A unique engagement portion that engages with an upper end of the screw shaft, and a key member for rotating the screw shaft by engaging the unique engagement portion with the screw shaft,
The insertion portion of the main body includes an upper cylindrical portion and a pair of long and short regulating legs extending continuously downward from the cylindrical portion,
The head portion of the screw shaft includes a corresponding engagement portion that engages with a specific engagement portion of the key member at an upper end portion,
The pair of long and short restricting legs are opposed to each other in a certain upper and lower range, and have a rotation restricting surface that restricts the nut member to a lock angle position between both surfaces.
The long restricting leg further includes a forward rotation restricting surface which is continuous with the rotation restricting surface downward and abuts a tightening protrusion of the nut member rotating in the forward direction to restrain the nut member at a lock angle position. A reverse rotation restricting surface that is 90 ° apart from the rotation restricting surface and abuts against the reverse rotation protrusion of the reversely rotating nut member to restrain the nut member at the unlocked angular position,
The nut member co-rotating with the positive rotation of the screw shaft is constrained to the lock angle position by the positive rotation restricting surface of the long restricting leg, and the nut member is locked to the rotation restricting surface at the lock angle position by further positive rotation of the screw shaft. An obturator for a manhole cover opening operation tool engagement hole, wherein the tightening protrusion is brought into contact with the lower surface of the manhole cover by being raised to the uppermost position. The engagement hole of the manhole cover is formed between a substantially semicircular arc-shaped notch formed at the peripheral edge of the manhole cover and the inner periphery of the manhole frame,
The umbrella portion has a substantially half-moon shape in close contact with the upper surface of the peripheral edge of the engagement hole,
The positioning projections face the inner circumference of the manhole frame body and restrict a rotation around the screw shaft, and a second positioning surface restricts the movement of the manhole cover in the center direction. The obturator for the opening operation tool engaging hole of the manhole cover according to claim 1.

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