JPH10266243A - Locking structure of cover for underground structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a locking structure which cannot be easily unlocked by a third person. SOLUTION: A locking part 6 and an unlocking engaging part 7 are provided in the inside of a receiving frame 2, and to the rear side of a cover body 3, a lock body 11 is provided, which is suspended so as to be turnable in the radial direction of the cover body 3 and to the upper part of which an engaging part 15 capable of being engaged with the locking part 6 and an abutting part 16 capable of being abutted on the unlocking engaging part 7 are formed. In the locked condition, the engaging part 15 is positioned below the locking part 6 so as to be locked, and also the abutting part 16 is situated in a locking position being apart from the unlocking engaging part 7, while in the unlocked condition, the abutting part 16 is shifted to the unlocking position below the unlocking engaging part 7 by turning the cover body 3 with regard to the receiving frame 2, and it is so constituted that the opening of the cover body 3 is enabled by disconnecting the engagement of the engaging part 15 with the locking part 6 by turning the lock body 11 in the unlocking direction so that the abutting part 16 is abutted on the unlocking engaging part 7 in accordance with the lifting-up operation of the cover body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking structure for a lid for an underground structure, and more particularly, to a locking structure for a lid for an underground structure capable of locking a lid body and a receiving frame supporting the lid body. As used herein, the term “cover for underground structure” refers to a large iron cover, a manhole cover, or the like that closes an opening that passes between an underground buried object, an underground structure facility, and the like in the sewer and the ground.
Sewage basin cover, openable and closable iron cover for power and communication underground facilities, underground cables, etc., iron cover for power transmission, iron cover for power distribution, buried conduit under water surface for water supply and gas piping and its accessories Fire hydrant cover, water control valve cover, partition valve cover, air valve cover, gas pipe cover, water meter cover, etc., which collectively function as an opening / closing door connecting equipment and the ground.

[0002]

2. Description of the Related Art A variety of lids for underground structures are provided at an upper end of the underground structure and open to the ground such as a road surface, and a lid body that is supported by the receiving frame by taper fitting or the like and covers the opening. The lid body is connected to the receiving frame by a hinge structure, so that when the lid is opened, the lid frame can be turned in a horizontal plane or turned over to the road surface side, and furthermore, locking for locking the lid main body and the receiving frame. It is common to provide a structure.

As a locking structure for locking the receiving frame and the lid body, there is, for example, one described in Japanese Utility Model Publication No. 58-3892. This locking structure has both a locking structure and a burl hole closing structure.A valve plate for closing a burl hole is provided at the upper end of an arm rotatably supported on the back surface of the lid body, and a valve plate is provided at the lower end. Are provided with hooks and weights that engage with projections on the inner peripheral surface of the receiving frame.

In the locked state, the arm is rotated in the locking direction by the weight of the weight, the valve plate closes the burl hole, and the hook engages with the lower surface of the projection on the inner peripheral surface of the receiving frame to be locked. ing. When unlocking, the valve plate is pushed down and the arm is rotated against the pressing force of the weight to release the engagement between the hook and the projection on the inner peripheral surface of the receiving frame.

[0005]

However, in the above-described locking structure, a bar-shaped tool such as a bur is inserted into the burr hole, and the lock can be unlocked by a simple operation of pushing down the valve plate. Anyone could easily open the lid body, preventing illegal intrusion into the underground structure, illegal dumping, etc., hindering the maintenance of the underground structure, or removing snow when removing snow There is a problem that the snow is dumped in the manhole and the burden of sewage treatment increases.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to provide a locking structure for a lid for an underground structure, which cannot be easily unlocked by a third party.

[0007]

According to the present invention, a locking portion and an unlocking engagement portion provided on an inner surface of a receiving frame, and a hanging portion rotatably mounted on a back surface of the lid body so as to be rotatable in a radial direction of the lid body. The lower portion comprises an engagement portion engageable with the locking portion and a lock body provided with an abutment portion capable of abutting on the unlocking engagement portion. In the locked state, the engagement portion is The locking portion is located below the locking portion and is locked, and the contact portion is in a locking position away from the unlocking engagement portion, and when unlocking, the lid main body is rotated with respect to the receiving frame. Thereby, the contact portion moves to the unlocking position below the unlocking engagement portion, and the contact portion comes into contact with the unlocking engagement portion with the lifting operation of the lid body. The lock body is rotated in the unlocking direction to release the engagement between the engaging portion and the locking portion.

In the above configuration, when unlocking, the operator inserts the tip of the opening jig into the opening hole of the opening jig to release the bite between the receiving frame and the lid body, and then moves the lid body to the receiving frame. By rotating, the contact portion of the lock body is moved to a locking position below the unlocking engagement portion of the receiving frame. Next, when the worker pulls up the lid body, the abutting portion comes in contact with the unlocking engagement portion to rotate the lock body in the unlocking direction, and the engagement portion of the lock body and the receiving frame Release the engagement with the locking part. The operator can open the lid by directly pulling the lid body upward.

On the other hand, if the lid body is lifted straight without rotating with respect to the receiving frame, the contact portion of the lock body does not come into contact with the unlocking engagement portion of the receiving frame, and the lock body rotates in the unlocking direction. It does not move. Therefore, the lid body cannot be opened. When closing the lid main body, the engaging portion of the lock main body is engaged with the locking portion of the receiving frame, and the abutment portion is adjusted to the locking position away from the unlocking engaging portion so that the lid main body is received in the receiving frame. Drop it inside. When the lid body falls into the receiving frame and the engaging portion exceeds the locking portion, the lock body rotates in the locking direction due to its own weight, and the locking portion is positioned below the locking portion of the receiving frame and locked.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the unlocking engaging portion is a projection provided on the inner surface of the receiving frame, and the abutting portion is formed so that the upper surface abutting the projection is radially outward of the lid body. It is configured to incline downward. With such a configuration, when the lid body is rotated with respect to the receiving frame, the contact portion of the lock body enters the lower side of the protrusion, and the upper surface thereof contacts the lower surface of the protrusion. The upper surface of the abutment portion is inclined downward toward the outside in the radial direction of the lid body, and when the lid body is pulled up, the lock body is moved radially inward of the lid body, that is, in the unlocking direction. And the engagement between the engaging portion and the locking portion is released.

Further, in the present invention, the unlocking engaging portion is a step surface provided on the inner surface of the receiving frame so as to be inclined downward toward the outside in the radial direction of the receiving frame. The upper surface is configured to contact the step surface. Even in such a configuration, when the lid body is rotated with respect to the receiving frame, the contact portion of the lock body enters below the step surface of the receiving frame, and the upper surface thereof contacts the step surface. The step surface is an inclined surface facing downward in the radial direction of the receiving frame, and when the lid main body is pulled up, the lock main body is smoothly rotated in the unlocking direction, thereby engaging with the engaging portion. The engagement with the stop is released.

In the present invention, an elastic member is provided on the inner surface of the receiving frame to prevent the contact portion from moving to the unlocking position below the unlocking engagement portion. The elastic member exerts a pressing force to prevent the contact portion from moving to the unlocking position, so that the locked state is stably maintained. In the present invention, an urging member for urging the lock main body in the locking direction is provided between the lock main body and the lid main body.

With this configuration, even when the lid body is installed on an inclined ground, the lock body is always urged outward in the radial direction of the lid body, that is, in the locking direction by the urging member regardless of the inclination. Therefore, the locked state can be stably maintained. Further, since there is no need to provide a weight portion on the lock body, the lock body can be made compact. Further, in the present invention, the lid body is provided with a bag-shaped opening jig insertion hole in which only the surface side of the lid body is open. If the jig insertion hole for opening the cover is formed in a bag shape, the inside of the lock main body becomes completely invisible, so that it is difficult for a third party to understand the unlocking method, and it is possible to prevent unnecessary opening of the cover.

(Embodiment 1) FIG. 1 is a sectional view showing a locking structure of a lid for an underground structure according to the present invention. FIG. 2 is a sectional view taken along the line II-II in FIG. In FIG. 1, the lid 1 for an underground structure has a circular shape in plan view constituted by a receiving frame 2 and a lid main body 3, and the upper surface thereof is placed flush with the ground surface (GL). The receiving frame 2 forms a fitting surface 2b with a lid body 3 having a tapered inner peripheral upper surface of the support portion 2a. The lid body 3 is fitted by reducing the outer peripheral surface of the rim winding 3a in a tapered shape. It is in contact with the surface 2b. The lid body 3 is connected to the receiving frame 2 by a hinge structure (not shown) so as to be openable and closable. The lid body 3 is lifted obliquely upward toward the front side while lifting the lid body 3 with respect to the receiving frame 2 to be horizontally turned or vertically inverted. This allows the lid to be opened. Then, the receiving frame 2 and the lid body 3
A locking portion 6 provided on the side of the receiving frame 2 at a position opposite to the hinge structure, and a lock body 11 provided on the side of the lid body 3 to be engaged with the locking portion 6. I have.

The above-described hinge structure is, for example, a receiving frame 2
An underground structure lid having a structure in which an annular hinge seat protrudes from the inner periphery of the base member and into which a hinge fitting rotatably mounted on the back surface of the lid body 3 is inserted is used. This hinge structure has a certain degree of freedom in the radial direction and the circumferential direction with respect to the hinge seat in a state where the hinge hardware is inserted into the hinge seat. The present embodiment also has such a hinge structure. Thus, the lid main body 3 can be slightly rotated in the circumferential direction with respect to the receiving frame 2, and at the time of opening the lid, the lid main body 3 can be pulled obliquely upward to the near side. Further, the lid body 3 is pushed straight up by the length of the hinge hardware when receiving turbulent lifting pressure inside the underground structure.

As shown in FIG. 3, the receiving frame 2 is formed with a tapered fitting surface 2b for fitting and supporting the lid body 3 on the upper inner peripheral surface of the support portion 2a, and a shelf on the lower end of the fitting surface 2b. 2c is formed in a step shape, and the inner peripheral surface 2d below the shelf 2c is formed in a cylindrical shape having a slightly smaller diameter than the fitting surface 2b. Receipt 2
A concave portion 5 that opens radially inward is formed on the inner peripheral surface 2d of the second member, and a locking portion 6 is formed along the circumferential direction at the upper edge of the opening of the concave portion 5. One side surface 5a of the recess 5
Is formed with an unlocking engagement portion 7 near the upper portion of the opening. An elastic member 8 slightly thicker than the length of the projection 7 is attached to the side surface 5a. The elastic member 8 is made of, for example, sponge rubber and can be compressed in the thickness direction (the longitudinal direction of the protrusion 7).

FIG. 4 shows a main part of the lid body 3 and the lock body 11.
In the exploded perspective view of FIG. 2, a bag-shaped burl hole 3c is provided at the peripheral edge of the lid body 3 so as to be located substantially at the center of the concave portion 5 formed on the inner peripheral surface 2d of the receiving frame 2 in the locked state. The bag-shaped burr hole 3c is opened at the peripheral portion of the front surface 3b of the lid main body 3, and the bag portion 3d bulges below the back surface. Lock body 11
The lower portion has a weight portion 12, and right and left sides of the weight portion 12 have side portions 13, 13 extending vertically upward, respectively, and a round bar-like shape extending horizontally outward on an upper end outer surface thereof. Arms 14 and 14 are formed. An engaging portion 15 is formed on the front surface of the weight portion 12 so as to be able to engage with the locking portion 6 of the receiving frame 2. Then, in the locked state of FIG.
A contact portion 16 is formed integrally with a side surface 15 a of the concave portion 5 provided on the receiving frame 2 on the side opposite to the side surface 5 a. The upper surface of the contact portion 16 is an inclined surface 16a which is inclined obliquely downward from the base end to the distal end as shown in FIG. The width of the contact portion 16 is substantially the same as the length of the protrusion 7 provided on the side surface 5a of the recess 5 as shown in FIG.

The lock body 11 is, as shown in FIG.
The width from the side surface 15b of the protrusion 5 to the side surface 16b of the contact portion 16 is narrower than the distance between the tip surface of the protrusion 7 on the side surface 5a of the recess 5 and the side surface 5b. Further, the lock body 11 is configured such that the engaging portion 16 is in the position where the side surface 16b of the contact portion 16 is in contact with the side surface 5a of the concave portion 5 and the position where the side surface 15b of the engaging portion 15 is in contact with the side surface 5b of the concave portion 5. Reference numeral 15 faces the engaging portion 6 so as to be engageable.

As shown in FIG. 5, brackets 3 are provided on the right and left sides of the bag portion 3d of the bag-shaped burr hole 3c on the back surface of the lid body 3.
e, 3e are provided. These brackets 3e,
3e is substantially L-shaped, the upper end of each vertical portion is continuously provided on the back surface of the lid body 3, and the free end of each horizontal portion has a predetermined distance from both side surfaces of the bag portion 3d of the bag-shaped bur hole 3c. And bolt holes 3f, 3f are formed in the vertical portion in the horizontal direction.

As shown in FIG. 1, both sides 13 and 13 of the lock body 11 are located between the brackets 3e and 3e of the bag-shaped burr hole 3c of the lid body 3 at the upper sides 13 and 13 of the weight 12. The arms 14, 14 are supported by the horizontal portions of the brackets 3e, 3e. The bag 3d is formed on the upper surface of the weight 12 of the lock body 11 and on both sides 1
It is stored in the space between 3 and 13. Further, as shown in FIGS. 1 and 5, the bolt holes 3 of the brackets 3e, 3e are formed.
Bolts 17 and 17 are screwed into f
Fourteen deviations are prevented. As a result, the lock main body 11 is rotatable in the radial direction of the lid main body 3 around the arms 14 and 14 as rotation axes, and is not movable in the circumferential direction. still,
The upper surface of the weight portion 12 of the lock main body 11 is
The lock main body 11 does not come into contact with the bag portion 3d when the lock body 11 rotates.

Next, the locking / unlocking operation will be described with reference to FIGS. 1, 2, 6 and 7. FIGS. 1 and 2 show a locked state in which the lid body 3 is fitted and supported in the receiving frame 2. The lock body 11 is in a substantially vertical state due to its own weight of the weight portion 12, and the distal ends of the engaging portion 15 and the contact portion 16 are in the
It is almost in the center of the inside. The engaging portion 15 is provided with the locking portion 6.
Is located slightly below and opposes the locking portion 6, and the side surface 16 b of the contact portion 16 is in contact with or slightly separated from the elastic member 8 attached to the side surface 5 a of the concave portion 5. . The contact portion 16 is spaced apart from the side of the protrusion 7, and the tip of the upper surface 16 a is located at a position slightly lower than the lower surface of the protrusion 7.

In this locked state, FIGS. 6 (a) and 6 (b)
When the lid main body 3 is lifted up to open as shown in FIG. 7, the engaging portion 15 of the lock main body 11 is engaged with the locking portion 6 of the receiving frame 2 to be locked, so that the lid main body 3 cannot be opened. Similarly, even when the lid main body 3 is pushed up by the gas pressure generated inside the underground structure or the turbulent lifting pressure, the lid main body 3 is locked by the lock main body 11 and the lid main body 3 is prevented from being opened or scattered. Is done.

When opening the lid main body 3, the tip of a special bar (not shown) is inserted into the bag-shaped burr hole 3c (FIG. 4) of the lid main body 3 to release the bite between the receiving frame and the lid main body. As shown in FIGS. 7 (a) and 7 (b),
Is rotated in the direction of arrow B with respect to the receiving frame 2. By this rotation operation, the lock main body 11 moves in the direction of arrow B together with the lid main body 3, the side surface 16 b of the contact portion 16 compresses the elastic member 8 and enters the lower side of the projection 7, and the inclined surface 16 a 7 to the unlocked position below. At this time, the recess 5 of the receiving frame 2
The side surface 16b of the contact portion 16 that has entered the elastic member 8
And the lid body 3 cannot rotate any more, so that the contact portion 16 is securely positioned at the unlocking position below the projection 7 as described above.

Next, as shown in FIG.
Is raised obliquely upward (in the direction of arrow C), the contact portion 16
Of the lock body 11 in the unlocking direction (inward in the radial direction of the lid body 3) when the inclined surface 16a of the
Is rotated. When the lid body 3 is further pulled up, FIG.
After the state of (d), as shown in FIG.
Is released from the locking portion 6 of the receiving frame 2 to be unlocked. Thereafter, as the lid body 3 is pulled up, the lock body 11
5 is pulled up in a state in which the tip of 5 comes into contact with the fitting surface 2b of the receiving frame 2 and is rotated in the unlocking direction.

As described above, in order to unlock, the lid body 3
Is required to be rotated with respect to the receiving frame 2, so that it is possible to prevent a third party who does not know the locking structure from easily unlocking. In the first embodiment, as shown in FIG. 6B, the lock body 11 is locked by the engagement portion 15 even at a position where the side surface 15 b of the engagement portion 15 contacts the side surface 5 b of the recess 5. The portion 6 can be engaged. Therefore, even if the lid main body 3 is rotated with respect to the receiving frame 2 in the direction of arrow A in FIG. 6B, the lock main body 11 cannot be unlocked and the lid main body 3 cannot be opened. .

In the first embodiment, the burr hole of the lid body 3 is formed as the bag-like burr hole 3c, so that the lock body 11 is not visible at all, so that the unlocking method is more difficult for a third party to understand. In addition, there is no danger that the lock body 11 is directly rotated by inserting a bar or the like from the burl hole and unlocked. Further, by forming the bag-shaped bur hole 3c, rainwater and earth and sand are prevented from entering the inside, and smooth operation of the lock body 11 is ensured.

Further, since the elastic member 8 is attached to the side surface 5a of the concave portion 5, when the contact portion 16 of the lock body 11 moves to the unlock position below the protrusion 7, the elastic member 8 The lid body 3 is easily rotated and unlocked when the lid body 3 floats due to the turbulent lift generated inside the underground structure. Thus, the locked state can be stably maintained.

On the other hand, when closing the lid body 3, the operator lifts the lid body 3, the engaging portion 15 engages with the locking portion 6 of the receiving frame 2, and the contact portion 16 engages with the projection 7. The lid body 3 is dropped into the receiving frame 2 in accordance with the locking position away from the cover frame 2. The lock body 11 descends in a state where it is rotated in the unlocking direction by the tip of the engaging portion 15 abutting on the fitting surface 2b of the receiving frame 2, and
When the distal end of the engaging portion 15 passes below the locking portion 6, the weight portion 12 rotates in the locking direction (outward in the radial direction of the lid body 3) due to its own weight, and the engaging portion 15 is moved. 1 and returns to the locked state as shown in FIGS.

In the first embodiment, a protrusion 7 is formed on one side surface 5a of the recess 5 as an unlocking engagement portion on the receiving frame 2 side.
The contact portion 16 is formed on one side surface 15a of the engaging portion 15 of the lock main body 11 on the side of the lid main body 3, but is not limited to this, and the projections are formed on both opposing side surfaces 5a and 5b of the concave portion 5 of the receiving frame 2. 7
Are formed, and both side surfaces 15a, 1 of the engaging portion 15 of the lock body 11 are formed.
The contact portions 16 may be formed on the respective portions 5b. In this case, the lock main body 11 can be unlocked by rotating the lid main body 3 in any direction with respect to the receiving frame 2, and the lock main body 3 can be unlocked in accordance with the installation condition (installation location) of the underground structure lid. Can be unlocked by rotating either one of them, thereby improving the unlocking operability. Further, the elastic member 8 is not limited to sponge rubber as in the embodiment, but may be an elastic body such as a spring or rubber.

(Embodiment 2) FIGS. 8 and 9 show a second embodiment of the locking structure of the present invention. As shown in FIG.
By forming the ridge 20 on the side surface 5a of the concave portion 5,
The lower surface is formed as a step surface 20a which is inclined obliquely downward from the upper portion of the opening end of the concave portion 5 toward the inside, and further has an upper surface 21a on the side surface 15a of the engaging portion 15 of the lock body 11, as shown in FIG. The contact portion 21 forming a horizontal plane is formed. When the lid body 3 is opened, the lid body 3 is rotated in the same manner as in the unlocking operation described above so that the contact portion 21 enters below the step surface 20a as shown in FIG. When the lid body 3 is lifted diagonally upward (in the direction of arrow C), FIG.
As shown in FIG. 0 (b), the lock body 11 is rotated in the unlocking direction and unlocked when the tip of the abutting portion 21 abuts on the step surface 20a. An elastic member is attached to the side surface 5a of the recess 5 as described above.

(Embodiment 3) FIGS. 11 and 12 show a third embodiment of the locking structure of the present invention. As shown in FIG. 11, by forming an inclined groove 23 on the side surface 5 a of the concave portion 5 of the receiving frame 2, the upper surface thereof is formed as a step surface 23 a which is inclined obliquely downward inward from near the upper end of the opening end of the concave portion 5. Further, as shown in FIG. 12, a contact portion 24 is formed on the side surface 15a of the engaging portion 15 of the lock body 11 so as to form a round bar and extend horizontally to contact the step surface 23a. When the cover body 3 is opened, the cover body 3 is rotated so that the contact portion 24 enters the inclined groove 23 as shown in FIG. When the lock main body 11 is lifted in the direction C, the lock main body 11 comes into contact with the contact portion 2 as shown in FIG.
4 is rotated in the unlocking direction by being in contact with the step surface 23a on the upper surface of the inclined groove 23 to be unlocked. An elastic member is attached to the side surface 5a of the recess 5 as described above.

In the above embodiment, the lock body 1
The lower part of 1 is a weight part 12, and the lock body 11 is urged in the locking direction by the weight of the weight part 12, but instead of this, between the back surface of the lock body and the back surface of the lid body. An elastic body such as a spring, rubber, or the like may be provided as an urging member to urge the lock body in the locking direction. By providing such an urging member, even when the lid main body is installed on an inclined ground, the lock main body is always urged in the locking direction regardless of the inclination, so that the locked state can be stably maintained. Also,
Since there is no need to provide a weight portion on the lock body, the lock body can be made compact. Of course, both the weight portion and the urging member may be provided.

[0033]

According to the locking structure of the lid for underground structures of the present invention, the lid body must be rotated with respect to the receiving frame in order to unlock, and the unlocking is achieved simply by inserting the jig for opening the lid. Since it cannot be performed, it is possible to prevent the lock from being easily unlocked by a third party. Further, at the time of the lid closing operation, the lock main body is pivoted down in the unlocking direction only by dropping the lid main body into the receiving frame, and when the lid is closed, the engaging portion of the lock main body is below the locking portion of the receiving frame. It is positioned and locked, and the locking operation is easy.

Further, the unlocking engagement portion is a projection, and the contact portion has an upper surface abutting on the lower surface of the projection inclined downward toward the outside in the radial direction of the lid body, so that the lid can be unlocked when unlocked. Since the upper surface of the contact portion comes into contact with the projection in accordance with the lifting operation of the main body and the lock main body can be smoothly rotated in the unlocking direction, the operability of unlocking is improved. In addition, the unlocking engagement portion may be a stepped surface provided on the inner surface of the receiving frame so as to be inclined downward toward the outside in the radial direction of the receiving frame. Since the main body can be smoothly rotated in the unlocking direction, the operability of unlocking is improved.

Further, an elastic member is provided on the inner surface of the receiving frame to elastically restrain the contact portion from moving to the unlocking position below the unlocking engagement portion. When the lid body moves, the elastic body exerts a pressing force to prevent it, so that the lid body can be easily rotated when the lid body floats due to the turbulent lift generated inside the underground structure. Movement and unlocking can be prevented, and the locked state can be stably maintained.

Further, by providing an urging member for urging the lock body in the locking direction between the lock body and the lid body, even when the lid body is installed on an inclined ground, the lock body is irrespective of the inclination. Is always urged in the locking direction, so that the locked state can be stably maintained. Further, since there is no need to provide a weight portion on the lock body, the lock body can be made compact.

Further, since the jig insertion hole for opening the lid is formed in a bag shape, the lock body attached to the back side of the lid body cannot be seen from the outside. This is even more effective in preventing useless unlocking by a third party. In addition, earth and sand, rainwater and the like do not enter the inside, and there is no danger that the lock main body will not operate due to the influence of rainwater and earth and sand.

[Brief description of the drawings]

FIG. 1 is a sectional view of Embodiment 1 of a locking structure of a lid for an underground structure according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a perspective view of a concave portion, a locking portion, and an unlocking engagement portion formed on the inner surface of the receiving frame of FIG. 1;

FIG. 4 is an exploded perspective view of a part of the lid main body and the lock main body of FIG.

FIG. 5 is a perspective view of the lid body of FIG.

FIG. 6 is an explanatory view showing a locking operation of the locking structure of FIG. 1;

FIG. 7 is an explanatory view showing an unlocking operation when the locking structure shown in FIG. 1 is opened.

FIG. 8 is a perspective view of a concave portion, an engaging portion, and an unlocking engaging portion formed on an inner surface of a receiving frame in Embodiment 2 of the present invention.

FIG. 9 is a perspective view of a lock body according to the second embodiment of the present invention.

10 is an explanatory view showing an unlocking operation of a locking structure to which the receiving frame shown in FIG. 8 and the lock body shown in FIG. 9 are applied.

FIG. 11 is a perspective view of a concave portion, a locking portion, and an unlocking engagement portion formed on an inner surface of a receiving frame according to a third embodiment of the present invention.

FIG. 12 is a perspective view of a lock body according to a third embodiment of the present invention.

13 is an explanatory diagram showing an unlocking operation of a locking structure to which the receiving frame shown in FIG. 11 and the lock body shown in FIG. 12 are applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cover for underground structures 2 Receiving frame 2a Support part 2b Fitting surface 3 Lid body 3a Edge winding 3c Bag-shaped burl hole (Jig insertion hole for lid opening) 3d Bag part 3e Bracket 3f Screw hole 5 Depression 6 Locking part 7 Projection (Engagement part for unlocking) 8 Elastic member 12 Weight part 13 Side part 14 Arm 15 Engagement part 16, 21, 24 Contact part 16a Inclined surface 20 Protrusion 20a, 23a Step surface (Unlocking engagement part) ) 23 Inclined groove

Claims (6)

[Claims] An engaging portion and an unlocking engaging portion provided on an inner surface of a receiving frame, and a hanging portion rotatably suspended on a back surface of the lid main body in a radial direction of the lid main body. A lock body provided with an engageable engaging portion and a contact portion capable of contacting the unlocking engaging portion, wherein the locked portion is located below the locking portion in a locked state. And the contact portion is at a locking position separated from the unlocking engagement portion, and at the time of unlocking, the contact portion is rotated by rotating the lid body with respect to the receiving frame. The lock body is moved in the unlocking direction by moving to the unlocking position below the unlocking engagement portion and the abutting portion abutting on the unlocking engagement portion with the lifting operation of the lid body. A locking structure for a lid for an underground structure, wherein the locking portion is moved to release the engagement between the engaging portion and the locking portion. 2. The unlocking engagement portion is a projection provided on the inner surface of the receiving frame, and the abutment portion has an upper surface abutting on the projection inclined downward toward the outside in the radial direction of the lid body. The locking structure of a lid for an underground structure according to claim 1, wherein: 3. The unlocking engaging portion is a stepped surface provided on the inner surface of the receiving frame so as to be inclined downward toward the outside in the radial direction of the receiving frame. 2. The underground structure lid locking structure according to claim 1, wherein the abutment contacts the step surface. 3. 4. The receiving frame according to claim 1, wherein an inner surface of the receiving frame is provided with an elastic member for preventing the contact portion from moving to an unlocking position below the unlocking engagement portion. Locking structure for lid of underground structure. 5. An underground structure lid lock according to claim 1, further comprising an urging member for urging the lock body in the locking direction between the lock body and the lid body. Construction. 6. A lid for an underground structure according to claim 1, wherein the lid main body is provided with a bag-shaped jig insertion hole for opening which is open only on the surface side of the lid main body. Locking structure.