JPH1136349A - Lock for lid body of manhole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a lid body from easily rising from its receiving frame by using a hook by fitting a cylindrical fitting portion of a lower opening of an operation handle to a rotation inhibitor and rotation lock means and also linking a catch portion provided at a cylindrical fittings to a linkage when removing the lid body from the receiving frame. SOLUTION: When removing a lock X from a lid body 22 for removing the lid body 22 from a receiving frame 21, a sucking member is first attached to a sealing member and it is removed from a storing place. Next, a cylindrical fitting portion 60 of an operation handle 26 is externally fitted to a rotation inhibitor 50 and rotation lock means 40, the external handle 26 is rotated and the lock X can be immediately removed from a linking lock portion 32 of the receiving frame 21. Here, if a linking hole for hook or a linking rod is not provided on the upper surface portion 35 of the lid body 22, a hook is attached to a linking hole 36 for a frame portion 23 for attaching the lock, and the lid body can be opened. Also, when fastening the lid body 22 to the receiving frame 21 through the lock X, this procedure should be performed in a reverse order.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock for a manhole cover which prevents a manhole cover from being opened by anyone other than an administrator or a person concerned.

[0002]

2. Description of the Related Art Conventionally, one embodiment of this kind is as shown in FIG. 11 (first embodiment described in Japanese Utility Model Publication No. 6-9074).

The basic structure of this conventional example will be described with reference to FIG.
Has an operating handle 4 having a magnet 3 at a lower portion, and an engaging recess 5 engaging and disengaging with the operating handle 4 on an upper surface, and
Directly or indirectly formed on the lid 1 (of the lock frame 6)
A lock lid 8 rotatably fitted into the opening / closing operation hole 7, and a lower part (inside) of the lock lid 8 which is vertically movable via a guide pin 9 provided integrally with the lock lid 8, And a movable lock body 11 having a lock lid rotation preventing projection 10,
A manhole receiving frame 1 is provided below the movable lock body 11.
A lock bolt 13 for integrally fastening the cover 2 and the cover 1 was provided.

Thus, the lock 2 of the manhole cover 1 is provided.
When the engagement protrusion of the operation handle 4 is aligned with the engagement recess 5 of the lid 1, the movable lock body 11 is raised by the magnet 3 of the operation handle 4 while being guided by the guide pin 9, and as a result, the movable lock The engagement of the lock lid preventing projection 10 of the body 11 is released, and the lock lid 8 is rotated through the operation handle 4 so that the lock lid 8 can be taken out from the opening / closing operation hole 7. Therefore, it is possible to rotate the lock bolt 13 with a tool (not shown) and release the fastening between the receiving frame 12 and the lid 1.

[0005] However, the above configuration has the following drawbacks. There are many components that make up a lock. Therefore, there are problems to be solved in terms of manufacturing and cost. Removal of the lock bolt 13 is not easy. That is, the lock of the lock bolt 13 cannot be released unless the lock lid 8 is removed by rotating the operation handle 4. That is, the operation handle 4 needs to be rotated with respect to the lock lid 8 and the lock bolt 13, respectively. There is a case where the movable lock body 11 does not rise due to the rust of the lid and the lock or the freezing in winter. For example, as shown in FIG. 11, steam S rising from the inside of the manhole enters the lock 2 through the gap of the lock frame 6 which locks the head of the lock bolt 13, and the inner wall surface of the lock lid 8, the movable lock body 1
If it adheres to the wall surface of 1 and the peripheral surface of the guide pin 9, the lock itself will rust as well as the manhole cover. As a result, there is a possibility that the movable lock body 11 does not rise even by the attraction force of the magnet 3 of the operation handle 4. Especially the inner wall surface 8 of the lock lid 8
When rust, corroded dust, etc. of the members accumulate in the space between the movable lock body 11 and the upper wall surface 11a of the movable lock body 11,
Has a problem that it does not work. Since the operation handle 4 is engaged only with the upper surface of the lock lid 8, it cannot be provided as desired so-called "key difference".

[0006]

SUMMARY OF THE INVENTION In view of the above problems, the first object of the present invention is to prevent the lid from being easily pulled up from the receiving frame by using a hook in order to open a manhole. Is to do so. A second object is to reduce the number of parts constituting the lock, thereby reducing the manufacturing cost. A third object is to be able to quickly remove the lock from the lid or attach the lock to the lid by a single rotation operation of the operation handle. A fourth object is that when the operation handle is used, the lock does not function due to rust, corrosion, freezing of steam, or the like of a member constituting the lock, and as a result, the lock cannot be removed from the lid. It is possible to prevent such situations as much as possible. For other purposes, depending on the embodiment, the fitting relationship between the lock and the operation handle is used,
That is, many "so-called key differences" can be provided.

[0007]

SUMMARY OF THE INVENTION A lock for a manhole cover according to the present invention is a manhole for locking a manhole receiving frame and a cover in a locked state by being locked by a lock mounting frame of the cover. In the lock of the lid, the lock (X, X1) includes rotation lock means (40, 40A) penetrating through the lock mounting frame and engaging with the locking lock of the receiving frame. A rotation obstruction element that is integrated with the rotation locking means from above into the storage recess of the lock mounting frame so as to obstruct the rotation of the means, and rotates idly while the rotation locking means is locked. The lock has at least one or more necessary engaging portions (44, 44A) on the rotation lock means, and operates when the cover is removed from the receiving frame. 26, 26A) cylindrical fitting part (60, 60A) at the lower end opening The rotating Shogaiko and outer fitted to the rotary locking means, and engaging portions provided on the tubular fitting portion (62, 62A), characterized in that the engaging said required engagement portion.

The lock for a manhole cover according to the present invention is a lock for a manhole cover which is locked to a lock mounting frame of the cover. The lock X2 is a lock for the lock mounting frame 23B. The rotation locking means 40B which engages with the locking lock portion 32B, and is integrated with the rotation locking means from above into the storage recess 24B of the lock mounting frame so as to hinder the rotation of the rotation locking means. And the rotation obstruction element 50 that idles while the rotation lock means is locked, wherein the lock has at least one or more necessary engagement portions 44 in the rotation lock means. When the lid 22B is pulled up from the receiving frame 21B, the cylindrical fitting portion 60 at the lower end opening of the operation handle 26 is fitted externally to the rotation obstacle and the rotation locking means,
The engaging portion provided on the cylindrical fitting portion engages with the necessary engaging portion. Further, the vertical lid portion 23a of the lock mounting frame portion 23B engages with the lid hook 70. It is characterized in that a mating engagement hole 36B is formed.

Further, the lock for a manhole cover according to the present invention is a lock for a manhole cover locked on a lock mounting frame portion of the cover, wherein the lock X2 is formed of the lock mounting frame portion 23B.
The rotation locking means 40B which engages with the penetrating locking lock part 32B formed on the horizontal bottom wall 23b of the horizontal direction, and the storage recess 24B of the lock mounting frame part so as to prevent the rotation locking means from rotating. And a rotation obstruction element 50 which is integrated with the rotation locking means from above and which rotates idly while the rotation locking means is locked, wherein the lock includes at least one rotation locking means. Necessary engaging portion 4 described above
4, when the lid 22B is pulled up from the receiving frame 21B, the cylindrical fitting portion 60 at the lower end opening of the operation handle 26 is fitted to the rotation obstacle and the rotation lock means, and
The engaging portion provided on the cylindrical fitting portion is engaged with the necessary engaging portion.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in the drawings will be described below with reference to an example of a lock X for a manhole cover according to a first embodiment.

First, FIG. 1 is a schematic explanatory view of a use state of a lock X of a manhole cover. 1, reference numeral 20 denotes a manhole, 21 denotes a manhole receiving frame, 22 denotes a lid fitted into the receiving frame, and X denotes a storage recess 24 of a lock mounting frame portion 23 of the lid 22. A lock for the lid incorporated into the lock from above, a magnet 25 or a seal member having a magnet for closing the opening of the storage recess 24 so as to fit on the outer peripheral wall of the lock or cover the lock, 26 After the seal member 25 is removed, the operation handle can be immediately fitted to the rotation obstacle and the rotation lock means of the lock X, and the locked state of the lock X can be released by a rotation operation.

Next, the main part of the present invention will be specifically described with reference to FIGS. The manhole receiving frame 21
As in the case of the ordinary receiving frame 21, the outer peripheral wall portion 2 having a rising shape is provided.
1a and opposed inner peripheral wall 2 forming a short cylindrical fitting recess 30
1b. Further, a female screw as an example of the locking lock portion 32 is formed in the inner horizontal plate portion 21 c forming the opening 31 of the receiving frame 21.

The lid 22 is substantially the same as that of the conventional embodiment, but is formed near the outer periphery of the upper surface 35 of the lid 22 and protrudes in the manhole direction. The difference is that hook engaging holes 36 (not shown) are formed at appropriate locations. Thus, it is possible to prevent deformation of the rotation locking means constituting the lock X when the lid 22 is forcibly opened.

The lock mounting frame 23 has a hook engaging hole 36 formed in a vertical peripheral wall 23a and a horizontal bottom wall 23b. There is a through hole 37 corresponding to the female screw 32. The through hole 37 and the hook engagement hole 36 are provided in the lock storage recess 2.
4, respectively. The upper end of the lock storage recess 24 is formed in a stepped shape, and the stepped portion has a flange 25a.
The ring-shaped seal member 25 having the shape just fits. Although the lock storage recess 24 has a slightly smaller diameter toward the bottom, it is desirable that the upper and lower portions have substantially the same diameter depending on the external shape of the tubular fitting portion of the operation handle 26.

The lock X is locked to the lock mounting frame 23 of the cover 22 and is provided with a rotation lock means 40 for fastening the manhole receiving frame 21 and the cover 22 in a locked state. And a rotation obstacle 50 which is incorporated into the storage recess 24 from above so as to obstruct the rotation and rotates idly while the rotation lock means 40 is locked.

The rotation lock means 40 may be a rotation lock rod having a horizontal locking piece which makes a line or surface contact with the lower surface of the inner horizontal plate portion 21c of the receiving frame 21 (when the locking lock portion 32 is a horizontally long hole). However, in this embodiment, a lock bolt that is screwed with the locking lock portion 32 of the receiving frame 21 is employed.

Therefore, as shown in FIG. 6, the lock bolt as an example of the rotation lock means 40 has an engagement head 41 integrally formed with the rotation obstacle 50 at the upper part, and a central part at the center. Is a flange-shaped peripheral body portion 42 connected to the engagement head 41
Are formed at the lower portion, and a threaded rod portion 43 connected to the flange-shaped peripheral body portion 42 is formed at each lower portion.

Thus, the engaging head 41 is attached to the rotation obstacle 5
It is inserted into a stepped engagement hole 51 formed in the lower part of the O. The outer diameter of the flange-shaped peripheral body 42 is desirably substantially the same as that of the rotation obstacle 50. When the lock bolt 40 is rotated in a locking (locking) direction by a tool (not shown), the threaded rod portion 43 is screwed to the locking lock portion 32 of the receiving frame 21 to a predetermined position, and the flange-shaped peripheral body portion 42 is locked. When it comes into contact with the horizontal bottom wall 23b of the mounting frame 23,
A complete fastening state between the lid 22 and the receiving frame 21 is achieved, and eventually the lid 22 is locked to the receiving frame 21 via the lock bolt 40.

In this embodiment, as shown in FIG. 3, in order to rotate the rotation lock means 40 with the operation handle 26, a plurality of necessary engaging portions (first Engaging portions) 44 are protruded at an arbitrary interval. In this embodiment, a total of four required engaging portions 44 are provided radially, but of course, one may be provided.

However, when it is desired to provide as many "so-called key differences" as possible together with the plurality of optional engaging portions 52 formed on the outer peripheral wall 50a of the rotation obstacle 50, the engaging portion of the operating handle 26 is required. Should be provided in consideration of the relationship between the two.

The rotation obstacle 50 locks the upper part of the rotation lock means 40 at its lower part, so that it rotates idly with the rotation lock means 40 locked. This rotation obstacle child 50
Has the stepped engagement hole 51 at the lower portion as described above, and has at least one or more optional engagement portions 52 on the outer peripheral wall 50a. Since the optional engaging portion 52 is provided to protrude when it is desired to provide as many "so-called key differences" as possible, it is an optional component. Appearance of rotation obstacle 50 and rotation locking means 40
Has the same shape (meaning a circle if the plane is circular, or a polygon if the plane is polygonal) so that the cylindrical fitting portion 60 at the lower end opening of the operation handle 26 is externally fitted.

When the lock X is incorporated into the lock storage recess 24 as shown in FIG.
Outer peripheral wall 50a and the outer peripheral wall 42 of the rotation locking means 40
A space is required between a and the inner peripheral wall of the vertical peripheral wall portion 23a of the lock mounting frame portion 23 for the cylindrical fitting portion 60 of the operation handle 26 to smoothly enter.

As shown in FIG. 3, the operation handle 26 is formed in a crank shape as a whole, and a handle portion 61 is provided on an upper side thereof so as to be connected to a lower cylindrical fitting portion 60. The operation handle 26 is, as shown in FIG.
2 is inserted into the lock storage recess 24 and externally fitted to the rotation obstacle 50 and the rotation lock means 40.

A plurality of engaging portions 62 are formed in the cylindrical fitting portion 60 in the vertical direction.
In the present embodiment, four notches 2 are formed in the present embodiment, with a notch in the vertical direction being provided at an arbitrary interval in the circumferential direction of the cylindrical fitting portion 60. The engaging portion 62 is a part of the optional engaging portion 5 of the rotation obstacle 50.
2 and the necessary engagement portion 44 of the rotation lock means 40, so that a vertical groove may be used instead of the vertical cutout.

The engaging portions 62 first engage with the optional engaging portions 52 of the rotation obstacle 50, and then engage with the necessary engaging portions 44 of the rotation locking means 40. If one of the engaging portions 62 of the operation handle 26 does not engage with one of the optional engagement portions 52 of the rotation obstacle 50, the cylindrical fitting portion 60 of the operation handle 26 cannot be pushed downward. This point is the same even when one engaging portion 62 of the operation handle 26 does not engage with one necessary engaging portion 44 of the rotation lock means 40. The plurality of engaging portions 62 of the operation handle 26 are provided with optional engaging portions 52 and necessary engaging portions 4 respectively.
In the case of linearly matching with No. 4, the state finally becomes as shown in FIG.

Next, a case where the lock X is removed from the receiving frame 21 or the lid 22 in the above configuration will be described.

As shown in FIG. 1, the lock X is installed from above into the storage recess 24 of the lock mounting frame 23 of the lid 22, and the lid 22 and the manhole receiving frame 21 are fastened in a locked state. ing. Therefore, in this state, the lid 22 cannot be easily removed from the receiving frame 21.

Therefore, when an administrator or the like removes the lock X from the lid 22 in order to remove the lid 22 from the receiving frame 21, first, the suction member M, which has a relation of applying a suction force to the seal member 25, is sealed. Apply to the upper surface of member 25. Suction member M
In this embodiment, since the seal member 25 is a magnet,
For example, a metal plate such as iron is sufficient. Of course, the attracting member M may have a magnet, and on the other hand, the sealing member 25 may be a metal plate to be attracted. The point is that the seal member 25 only needs to be adsorbed by the suction member M and come off the storage recess 24.

Next, as shown in FIG. 5, the operation handle 26 is externally fitted to the rotation obstacle 50 and the rotation lock means 40 of the lock X. In this case, the cylindrical fitting portion 60 does not fit with the rotation obstacle 50, or the engaging portion 62 of the cylindrical fitting portion 60 does not engage at least with the necessary engaging portion 44 of the rotation lock means 50. In such a case, the rotation obstacle 50 is "idling"
I do. Therefore, the rotation obstruction element 50 causes a rotation obstruction, and the rotation locking means 40 cannot be rotated.

Therefore, the cylindrical fitting portion 6 of the operating handle 26 is
When 0 is externally fitted to the rotation obstacle 50 and the rotation locking means 40, the operation handle 26 is rotated, and the lock X can be immediately removed from the locking lock portion 32 of the receiving frame 21 as shown in FIG. . In this case, in this embodiment, the lid 22
Although the engagement hole 36 of the lock mounting frame portion 23 is not a specific requirement of the invention, the upper surface portion 35 of the lid 22 is similar to a normal lid.
If no hook engaging hole or engaging bar is provided on the cover 2, a hook (not shown) is hooked on the
2 can be opened. When the cover 22 is fastened to the receiving frame 21 via the lock X, the above procedure may be reversed.

[0031]

In this section, a description will be given of a modification (second embodiment) of the main part of the first embodiment, and a third embodiment in which the object of the invention is considered to be the same as that of the first embodiment. In the description of these embodiments, portions having the same configuration as those of the first embodiment are denoted by the same or similar reference numerals, and duplicate description will be omitted.

FIGS. 7 and 8 show a modification of the main part of the first embodiment. The necessary engagement portion 44A of the rotation lock means 40A and the rotation obstacle 50A constituting the lock X1 of the second embodiment are provided.
Are different from the first embodiment in that each of the optional engaging portions 52A is a vertical cutout groove. Therefore, as shown in FIG. 8, the cylindrical fitting portion 60A of the operation handle 26A
The engaging portion 62A is formed as a vertical projection so as to vertically engage the optional engaging portion 52A and the necessary engaging portion 44A.

For example, the same operation and effect as those of the present invention can be obtained even if the main part of the first embodiment is designed and modified at the level of those skilled in the art.

FIGS. 9 and 10 show a second embodiment. The second embodiment is that the cover 22B and the receiving frame 21B are not necessarily fastened by the lock X2.

That is, the lock X2 of the second embodiment is installed from above into the storage recess 24B of the lock mounting frame 23B, and the horizontal bottom wall 23 of the lock mounting frame 23B.
b, and is locked by a locking lock portion 32B formed therein.
The locking lock portion 32B is provided with a rotation locking means 40, similarly to the locking lock portion 32 of the receiving frame 21 of the first embodiment.
B is a female screw that is screwed with a lock bolt as an example.

Therefore, the lock X2 is made up of the lid 22B and the receiving frame 2B.
Hook obstruction means (this is referred to as a "lock" for the sake of convenience) for preventing the lid 22B from being pulled up from the receiving frame 21B via the hook 70, rather than fastening means for locking the lid 22B. In the second embodiment, the rotation locking means 40B does not necessarily have to penetrate the locking lock portion 32B of the lock mounting frame portion 23B. The engagement hole 36B formed in the vertical peripheral wall portion 23b of the frame portion 23B is a requirement for specifying the invention in relation to one object of the invention.

In the above configuration, after the lock X2 is removed from the storage recess 24B formed by the lock mounting frame 23B, the hook 70 is passed through the locking lock 3
2B, or into the engagement hole 36B of the vertical peripheral wall 23b of the lock mounting frame 23B, and lift the lid 22B.

Therefore, the second embodiment, like the first embodiment, satisfies the common purpose that the lid cannot be easily pulled out of the receiving frame by using the hook 70 to open the manhole. it can.

[0039]

As is clear from the above description, the present invention has the following effects. (1) It is possible to prevent the lid from being easily lifted from the receiving frame by using the hook. (2) The number of parts constituting the lock can be reduced. (3) The lock can be attached to and detached from the lid by a single rotation operation of the operation handle. (4) A situation in which the lock cannot be removed from the lid can be prevented as much as possible.

[Brief description of the drawings]

1 to 6 are explanatory views showing a first embodiment of the present invention. 7 and 8 are explanatory views showing a second embodiment of the present invention. FIG.
And FIG. 10 are explanatory views showing a third embodiment of the present invention.

FIG. 1 is an overall explanatory view showing an embodiment;

FIG. 2 is an explanatory view of a main part in FIG. 1;

FIG. 3 is a perspective view of an operation handle and a lock.

FIG. 4 is an explanatory view of a state where a sealing member is first removed in FIG. 2;

FIG. 5 is an explanatory view showing a state in which the operation handle is next fitted to the lock in FIG. 4;

FIG. 6 is an explanatory view showing a state in which the operation handle is rotated next and the lock is removed in FIG. 5;

FIG. 7 is an explanatory view similar to FIG. 2 of a second embodiment.

FIG. 8 is an explanatory view similar to FIG. 3 of a second embodiment.

FIG. 9 is an explanatory diagram of a main part of a third embodiment.

FIG. 10 is an explanatory view showing a state in which the lock is removed and the lid is pulled up by the hook in FIG. 9;

FIG. 11 is a schematic sectional view of a main part of a conventional example.

[Explanation of symbols]

X, X1, X2: lock, 21, 21B: receiving frame, 22, 22
B: lid, 23, 23B: lock mounting frame, 23a: vertical peripheral wall, 23b: horizontal bottom wall, 24, 24B: storage recess, 25: seal member, 26, 26A: operation handle,
32, 32B: locking portion, 35B: upper surface, 36,
36B: engagement hole, 40, 40A, 40B: rotation lock means, 44, 44A: required engagement portion, 50, 50A: rotation obstacle, 52: optional engagement portion, 60A: cylindrical fitting portion, 6
2, 62A: hook portion, 70: hook, M: suction member.

Claims (7)

[Claims] 1. A lock for a manhole cover, which is locked to a lock mounting frame of the cover and fastens the manhole receiving frame and the cover in a locked state, wherein the locks (X, X1) are Rotating lock means (40, 40A) which penetrates through the lock mounting frame and engages with the locking lock of the receiving frame, and the lock mounting frame which prevents rotation of the rotary locking means. A rotation obstruction element (50, 50A) that is integrated into the storage recess from above with the rotation lock means and that rotates idly while the rotation lock means is locked; The means has at least one or more necessary engaging portions (44, 44A), and when the lid is removed from the receiving frame, the cylindrical fitting portion (60) of the lower end opening of the operating handle (26, 26A). , 60A) are externally fitted to said rotation obstacle and rotation locking means, And a locking portion (62, 62A) provided on the cylindrical fitting portion engages with the necessary engaging portion. 2. A lock (X, X1) according to claim 1, wherein said lock (X, X1) has an outer peripheral wall provided with a necessary engagement portion (44, 44A) of rotation lock means. At least one or more optional engagement portions (52,5) that coincide on a vertical line
2A), while the operating handles (26, 26)
A) The engaging portions (62, 6) of the cylindrical fitting portions (60, 60A)
2A) A lock for a manhole cover, wherein the lock is formed in a vertical direction so as to first engage with the optional engaging portion and then engage with the necessary engaging portion. 3. The lock for a manhole cover according to claim 1, wherein a seal member for closing an opening of the storage recess is detachably fitted to the cover. 4. An engaging hole 3 for engaging with a lid hook in the vertical peripheral wall portion 23a of the lock mounting frame portion according to claim 1.
6. A lock for a manhole cover, wherein 6 is formed. 5. A lock of a manhole cover locked by a lock mounting frame portion of a lid, wherein a lock X2 is engaged with a locking lock portion 32B of the lock mounting frame portion 23B. The locking means 40B is integrated with the rotation locking means from above into the storage recess 24B of the lock mounting frame so as to obstruct the rotation of the rotation locking means. Rotating obstacle 50 spinning in a stopped state
Wherein said lock comprises at least one
When the lid 22B is pulled up from the receiving frame 21B, the cylindrical fitting portion 60 at the lower end opening of the operation handle 26 is fitted to the rotation obstacle and the rotation locking means when the lid 22B is pulled up from the receiving frame 21B. The engaging portion provided on the cylindrical fitting portion engages with the necessary engaging portion, and further, a hook for lid is provided on the vertical peripheral wall portion 23a of the lock mounting frame portion 23B. 7
A lock for a manhole cover, wherein an engagement hole (36B) for engaging with the lock is formed. 6. The lock according to claim 5, wherein the outer peripheral wall of the rotation obstacle 50 constituting the lock X2 has at least one or more optional parts which coincide with the required engagement portion of the rotation lock means on a vertical line. An engaging portion is provided, while the engaging portion of the tubular fitting portion of the operation handle is first engaged with the optional engaging portion, and then vertically engaged with the necessary engaging portion. A manhole cover lock characterized by being formed. 7. A lock for a manhole cover which is locked to a lock mounting frame of the lid, wherein the lock X2 is formed by a through hole formed in a horizontal bottom wall 23b of the lock mounting frame 23B. Rotation locking means 40B engaged with the locking lock portion 32B in the state
A state in which the rotation locking means is integrated with the rotation locking means from above into the storage recess 24B of the lock mounting frame so as to prevent rotation of the rotation locking means, and the rotation locking means is locked. The lock has at least one or more necessary engaging portions 44 in the rotation lock means, and the lid 22B is attached to the receiving frame 21B.
When it is lifted from the operating handle 26, the cylindrical fitting portion 60 at the lower end opening of the operating handle 26 is fitted externally to the rotation obstacle and the rotation locking means, and the engaging portion provided at the cylindrical fitting portion is required. A lock for a manhole cover, which is engaged with a target engaging portion.