JP4871195B2 - Locking structure for lids for underground structures - Google Patents

Description

  The present invention relates to a locking structure for a lid for an underground structure provided in an opening portion of a ground surface (manhole where mainly people can enter and exit) leading to an underground structure such as a common ditch or a sewer pipe.

  A rigid receiving frame that forms an opening edge is installed in the opening portion of the ground surface that leads to underground structures such as common grooves and sewer pipes, and the opening body is closed by fitting the lid body in the receiving frame. However, such a lid for an underground structure is generally provided with a locking structure so that the lid body is not opened by an outsider or pressure in the underground structure.

  As a typical example of such a locking structure, a pendulum-shaped locking body is swingably supported on the back surface of the lid body, and a latch portion formed on the locking body is engaged with an inner peripheral portion of the receiving frame by its own weight. The ones that match are known. Then, according to this type of locking structure, by inserting a bar or the like into a tool insertion hole formed on the peripheral edge of the lid body, the locking body is swung to release the lock, and in this state the lid body is It can be lifted to release it.

  Here, since the earth and sand etc. will flow into the underground structure from there when the tool insertion port is always open, in Patent Document 1, a lock body (engagement protrusion) forming a latching portion (engagement protrusion) ( A closing plate for closing the tool insertion opening (opening) is attached to the locking rod) via an elastic member so as to be pressed down.

  In Patent Document 2, a guide surface for guiding the closing plate to the locking body (locking rod) is provided so that the closing plate does not come into contact with the inner peripheral surface of the receiving frame when the tool insertion opening (opening) is opened and closed. On the other hand, the closing plate is provided with a convex portion that slides on the guide surface when the closing plate is lowered.

No. 7-56357

Japanese Patent No. 3616920

  However, according to what has the obstruction board which obstruct | occludes a tool insertion port like patent document 1, 2, it can prevent that rainwater and earth and sand flow in into an underground structure through a tool insertion port. However, since a large gap is generated between the closing plate and the back surface of the lid body when the closing plate is pushed down, a malicious third party who does not have a dedicated tool is generally used with a crane or a metal rod that is commercially available. There was a risk that the lid body could be peeled open.

  In Patent Documents 1 and 2, since the axis of the rocking fulcrum of the locking body passes directly under the tool insertion slot, the tip of the crane is inserted between the closing plate and the back surface of the lid body. Even if it is possible to open the cover other than the dedicated tool, it is difficult to release the lock by the locking body unless the closing plate is pressed on the outer peripheral side from the fulcrum position of the locking body. However, depending on the fulcrum position of the locking body, it can be unlocked by swinging the locking body while inserting a conventional metal rod between the closing plate and the back of the lid body. The lid body can be easily opened with a stick or the like.

  The present invention has been made in view of the circumstances as described above, and its main purpose is to prevent the underground structure lid from being opened by a malicious third party. .

In order to achieve the above object, the present invention
A locking body that has a tool insertion opening formed at the peripheral edge of the lid main body fitted to the upper end opening of the receiving frame, and is swingably supported on the back surface of the lid main body in the vicinity of the tool insertion opening. And a latch part that engages with an inner peripheral part of the receiving frame is formed on the locking body,
Between the locking member and the lid body, closing plate for closing the tool insertion port is provided so as to be pushed down,
The closing plate is fixed to the upper end of a slide shaft extending downward from the back surface portion thereof,
Inside the locking body, there is a shaft guide path for sliding the slide shaft in the axial direction, and elasticity for urging the closing plate toward the tool insertion port along the axial direction of the slide shaft. A member is provided,
Wherein the closure plate, prior Symbol than said closure portion adjacent the full closure portion fitted in the tool insertion port barrier projection is provided in a position which is the center side of the lid body,
When the closing plate is lowered by the pressing of the plug portion, the barrier protrusion is located on the center side of the lid body from the tool insertion port and is located on the upper side closer to the back surface of the lid body than the plug portion. It is intended to provide a locking structure for a lid for an underground structure, which is characterized as described above.

  In particular, a recess for engaging the tip of a predetermined tool is formed on the back surface of the lid main body at a position adjacent to the tool insertion opening and closer to the center of the lid main body than the tool insertion opening. When the tool insertion port is closed by the fitting of the plug portion, the barrier protrusion is inserted into the recess.

  According to the present invention, the closure plate is provided with a plug portion that fits into the tool insertion port, and a barrier projection is provided at a position adjacent to the plug portion and closer to the center side of the lid body than the plug portion. When the closure plate is lowered due to the pressing of the plug part, the barrier protrusion is located closer to the center side of the lid body than the tool insertion port and closer to the back side of the lid body than the plug part due to the rocking of the locking body. Since it did, it can prevent that a big space | gap arises between the back surface of a lid | cover main body, and a closure board. Therefore, even if a metal rod or crane other than the predetermined tool is inserted from the tool insertion slot, the tip of the metal bar interferes with the obstacle protrusion and cannot be inserted deep into the center side of the lid body. It is possible to prevent the lid body from being opened by a third party.

  In addition, a concave portion for engaging the tip of a predetermined tool is formed on the back surface of the lid body adjacent to the tool insertion slot at a position closer to the center side of the lid body than the tool insertion slot. The lid body can be easily opened by engaging the tip of the predetermined tool with the recess, and the barrier projection is inserted into the recess when the tool insertion port is closed by the fitting of the plug portion. Therefore, the interference protrusion can be prevented from interfering with the lid body, and the tool insertion port can be satisfactorily closed by the plug portion.

  Hereinafter, application examples of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a cover for an underground structure according to the present invention partially cut away, and FIG. 2 shows the same cross section. 1 and 2, reference numeral 1 denotes a rigid annular receiving frame that forms a tapered opening at the upper end. The receiving frame 1 is embedded in the vicinity of the ground surface so as to form an upper opening edge of a manhole, for example, and its upper surface is the ground surface. It is fixed to the ground to match. In particular, a lock receiver 11 that protrudes downward is integrally formed on the inner periphery of the receiving frame 1.

  Reference numeral 2 denotes a circular lid body (manhole lid) fitted to the upper end opening of the receiving frame 1, and a semicircular tool insertion port 21 formed by cutting out a part of the periphery is formed on the back surface thereof. A lock support portion 22 is formed in the portion adjacent to the tool insertion port 21.

  The lid body 2 is linked to the receiving frame 1 by a hinge fitting (not shown) installed on the back side opposite to the tool insertion opening 21 so as to be opened and closed. When the lid is closed, the tool insertion facing the hinge fitting is provided. The mouth 21 is positioned above the lock receiver 11.

  In particular, on the back surface of the lid body 2, the locking body 3 is swingably supported in the vicinity of the tool insertion port 21 as a main component of the locking structure that prevents the lid body 2 from being opened. The lock body 3 is a cast block structure having a latch portion 31 that engages with the lock receiver 11, and includes a closing plate 4 for closing the tool insertion port 21 of the lid body 2, and the closing plate 4. Is attached to the elastic member 5 (in this example, a metal coil spring) for urging the tool toward the tool insertion port 21.

  As is apparent from FIG. 2, the closing plate 4 is provided between the back surface of the lid body 2 and the locking body 3 so as to be able to be pushed down against the urging force of the elastic member 5. The plug portion 41 fitted into the plug portion and the obstacle protrusion 42 adjacent to the plug portion are integrally projected. The obstacle protrusion 42 has a triangular cross section and is formed at a position closer to the center side of the lid body 2 than the stopper portion 41 (near the center of the lid body 2). On the other hand, a recess 23 is formed on the back surface of the lid body 2 adjacent to the tool insertion port 21 at a position closer to the center of the lid body 2 than the tool insertion port 21, and the tool insertion port 21 is plugged. The obstruction projection 42 is configured to enter the recess 23 when it is closed by the fitting of the portion 41.

  And according to the locking structure which concerns on this invention, the tool insertion port 21 is obstruct | occluded by the closure board 4 at the time of a lid closing, and the predetermined tool 6 inserted in the tool insertion port 21 at the time of a lid opening as shown in FIG. When the plug portion 41 is pressed, the closing plate 4 is lowered against the urging force of the elastic member 5, and the locking body 3 is swung in synchronism with this to form the locking body. The latch portion 31 is separated from the lock receiver 11. 4 is a perspective view showing a state in which the locking is released by the upward swinging of the locking body 3 toward the center side of the lid body 2, but FIG. 4 does not show a tool.

  Here, the tip of the tool 6 is engaged with the recess 23 as shown in FIG. 3, but when the closing plate 4 is lowered by the pressing of the plug portion 41 by the tool 6, the obstacle protrusion 42 of the closing plate 4 is locked. 3 is located on the center side of the lid body 2 from the tool insertion port 21 and closer to the back surface of the lid body 2 than the plug portion 41, and between the lid body 2 and the closing plate 4. It works to prevent the formation of large voids. In addition, the effect by this is mentioned later.

  Next, the structure of the locking body will be described in detail with reference to FIGS. 5 to 8. The locking body 3 has the latch portion 31 corresponding to the lock receiver 11 of the receiving frame 1 as described above, and the latch portion 31. Is protruded obliquely upward from the lower part of the back surface directed toward the inner peripheral surface side of the receiving frame 1. Further, a pair of left and right arm portions 32, 32 extending upward are formed on the left and right side surfaces of the locking body 3, and a circle formed as a swing fulcrum from the upper end of both arms 32, 32 toward the left and right outwards. Columnar pivot portions 33, 33 are projected.

  Further, on the upper portion of the locking body 3, a pair of left and right projecting portions 34, 34 are formed between the pair of arm portions 32, 32 that rise obliquely toward the back side. Both the protrusions 34 and 34 function to prevent the locking body 3 from approaching the inner peripheral side of the receiving frame 1 by contacting the back surface of the lid body 2 when the lid is closed (see FIG. 2).

  Here, according to the locking body 3, the cylindrical hollow portion 35 is formed at the center, and the groove-shaped shaft guide paths 36 and 36 having a concave cross section are formed on the inner wall surface of the hollow portion 35. They are formed opposite to each other. As is apparent from FIG. 8, the hollow portion 35 has a vertically long shape having a bottom surface portion 37, and an upper portion thereof is opened between the arm portions 32 and 32. On the other hand, the shaft guide path 36 has a linear shape extending in the length direction of the hollow portion 35, and both ends thereof are opened in the vertical direction.

  9 and 10 are perspective views showing a state in which the closing plate 4 is assembled to the locking body 3. As apparent from these drawings, the closing plate 4 has a structure in which the plug portion 41 and the obstacle protrusion 42 are integrally provided on a thin plate-like seat plate portion 43, and the plug portion 41 is formed by the tool insertion port 21. The obstruction protrusion 42 is an arcuate ridge having a triangular cross section. Note that the entire width of the closing plate 4 is smaller than the distance between the both arm portions 32 and 32 of the locking body 3, thereby enabling the closing plate 4 to move vertically between the both arm portions 32 and 32. .

  In particular, the closing plate 4 is fixed to one end of two slide shafts 7 and 7 so that the slide shafts 7 and 7 extend downward from both sides of the back surface of the closing plate 4 in parallel with each other. The slide shafts 7 and 7 have a prismatic shape, and a disc-shaped pressure receiving plate 8 (see FIGS. 2 and 3) is fixed between the slide shafts 7 and 7, and the two slide shafts 7 and 7 are formed by the pressure receiving plate 8. It is a configuration to be connected. The pressure receiving plate 8 may be in a form other than a disk shape, and the point is that the pressure receiving plate 8 may be moved along the shaft guide path 36 while being supported by the elastic member 5 in the hollow portion 35. Further, the closing plate 4, the slide shaft 7 and the pressure receiving plate 8 may be integrally connected with each other, or may be integrally formed by casting or the like.

  The two-legged closure plate 4 as described above is combined with the locking body 3 by fitting the slide shafts 7 and 7 into the shaft guide paths 36 and 36 formed in the locking body 3. Since the slide shafts 7 and 7 are slid along the shaft guide paths 36 and 36, the closing plate 4 is supported in the direction of the slide shafts 7 and 7 while being supported by the slide shafts 7 and 7. Can move.

  The elastic member 5 is disposed between the slide shafts 7 and 7 below the pressure receiving plate 8, and the elastic member 5 is accommodated in the cavity 35 of the lock body 3. Then, the tip plate 9 is fixed to the upper surface of the locking body 3 with screws as shown in FIG. 10, the upper end opening portion of the cavity 35 is closed by the tip plate 9, and the pressure receiving plate 8 is placed in the cavity 35. The elastic member 5 is elastically supported. The chip plate 9 serves to prevent the sewage and dust from entering the hollow portion 35 and to prevent the slide shafts 7 and 7 from being removed.

  Here, when the upper surface of the closing plate 4 (plug portion 41) is pressed, the pressure is applied to the elastic member 5 from the slide shafts 7 and 7 through the pressure receiving plate 8, and the closing member 4 is reduced while the elastic member 5 is reduced. When the pressure on the closing plate 4 is released, the pressure receiving plate 8 is pushed by the elastic member 5 and the slide shafts 7 and 7 are slid toward the closing plate 4 so that the closing plate 4 moves upward. Is to be done.

  Next, the structure of the lid body will be described with reference to FIGS. 11 and 12. A pair of side walls 22 </ b> A and 22 </ b> A sandwiching the position of the tool insertion port 21 is provided on the back surface of the lid body 2 to suspend the locking body 3. The lock support portion 22 is formed. Concave grooves 22B and 22B, each of which is closed at one end, are formed on the inner side surfaces of both side walls 22A and 22A. The closed ends of the concave grooves 22B and 22B support the pivot portion 33 of the lock body in a rotatable manner. , 22C. Then, as shown in FIG. 12, stoppers 22D (bolts in the illustrated example) are attached to the concave grooves 22B and 22B adjacent to the bearing portions 22C and 22C, and the pivot portions 33 and 33 are connected to the bearing portions 22C by the stopper 22D. , 22C.

  As shown in FIG. 11, the axis L of the pivot 33 supported by the bearing 22 </ b> C (the center of swinging of the locking body 3) deviates from the position of the tool insertion port 21, so Therefore, when the plug portion 41 of the closing plate 4 fitted to the tool insertion port 21 is pressed, the locking plate 3 is lowered and the locking body 3 is centered on the pivot portion 33. Will swing to the unlocking side (the center side of the lid body 2).

  Next, the operation of the present invention will be described. Here, when the lid body 2 is opened, as shown in FIG. 3, the tip end portion of the bowl-shaped (J-shaped) tool 6 is inserted into the tool insertion port 21, whereby the closing plate 4 (plug portion 41). ) Is pressed. Then, the closing plate 4 descends against the elasticity of the elastic member 5, while the locking body 3 swings toward the center side of the lid body 2 by the pressing force. As a result, since the latch portion 31 is separated from the lock receiver 11 and the lid body 2 is unlocked, the lid body 2 is opened by pulling up the lid body 2 while engaging the tip of the tool 6 with the recess 23. can do.

  In addition, according to the tool 6 as shown in FIG. 3, the front end can be easily engaged with the concave portion 23 through the narrow gap between the lid main body 2 and the obstacle protrusion 42, so that the lid main body 2 can be easily opened. In the case of a mere metal rod S as shown in FIGS. 13 to 15 or a crane rod (not shown), even though the closing plate 4 can be pushed down, the intrusion is hindered by the obstruction protrusion 42 and its tip is not allowed to be inserted deeply. In addition, in the state where the tip of the metal rod S is in contact with the obstacle protrusion 42, the latch body 31 of the locking body 3 faces the lock receiver 11 as shown in FIG. 15, and the locking is not released, so the lid body 2 cannot be opened. .

  As described above, in the closing plate 4 having the obstacle protrusions 42, the lid main body 2 is removed by using a metal rod S or the like by a malicious third party while allowing the predetermined tool 6 to open the lid main body 2. The effect that it can be prevented from being opened is obtained. Note that examples of the predetermined tool that can easily open the lid body 2 include a tool 6 ′ whose tip is bent in an L shape, as well as a tool 6 whose tip is bent in a J shape as shown in FIG. 16.

  As described above, the present invention has been described, but it is sufficient that the obstacle protrusion is provided at least at a position closer to the center side of the lid body 2 than the plug portion 41. That is, if the position closer to the center side of the lid body 2 than the stopper portion 41 is included, a semicircular arc-shaped obstacle including portions adjacent to the stopper portion 41 on both sides in the circumferential direction of the lid body 2 as shown in FIG. The protrusion 42 ′ may be used. Further, if the recess 23 is formed on the back surface of the lid body 2, the tools 6, 6 'are opened when the lid is opened while preventing the obstacle protrusions 42, 42' from interfering with the back surface of the lid body 2 when the lid is closed. However, it is also possible to set the lid body 2 to a thickness that does not interfere with the obstacle projections 42 and 42 ′ and to omit the recess 23. However, in this case, it is necessary to take measures to give the lid body 2 the required strength.

  In the above example, the closing plate 4 is attached to the locking body 3 via the two slide shafts 7, but one slide shaft 7 may be provided.

The perspective view which fractured | ruptured and showed the principal part of this invention (at the time of lid closing) Cross-sectional view of essential parts of the present invention (when closed) Cross-sectional view of the main part of the present invention (state immediately before opening the lid) The perspective view which fractured | ruptured and showed the principal part of this invention (state just before a lid opening) The perspective view which looked at the lock body from the front side The perspective view which looked at the lock body from the back side Top view of locking body XX sectional view in FIG. The perspective view which looked at the locking body where the obstruction board was assembled from the back side The perspective view which looked at the locking body where the obstruction board was assembled from the side Back view of the lid body showing the periphery of the tool slot YY enlarged sectional view of FIG. Cross-sectional view of the main part showing the state of the closing plate when a tool other than the predetermined tool is inserted into the tool insertion slot Main part perspective view showing a state when a tool other than a predetermined tool is inserted into the tool insertion slot Cross-sectional view of the main part showing the state of the locking body when a tool other than the predetermined tool is inserted into the tool insertion slot Explanatory drawing which shows the predetermined tool used for the lid opening of this invention Explanatory drawing which shows the modification of an obstruction protrusion

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Receiving frame 11 Lock receiving 2 Lid main body 21 Tool insertion slot 23 Recessed part 3 Locking body 31 Hatch part 33 Pivot part 4 Closure board 41 Plug part 42,42 'Obstruction protrusion 5 Elastic member 6,6' Predetermined tool

Claims (2)

A locking body that has a tool insertion opening formed at the peripheral edge of the lid main body fitted to the upper end opening of the receiving frame, and is swingably supported on the back surface of the lid main body in the vicinity of the tool insertion opening. And a latch part that engages with an inner peripheral part of the receiving frame is formed on the locking body,
Between the locking member and the lid body, closing plate for closing the tool insertion port is provided so as to be pushed down,
The closing plate is fixed to the upper end of a slide shaft extending downward from the back surface portion thereof,
Inside the locking body, there is a shaft guide path for sliding the slide shaft in the axial direction, and elasticity for urging the closing plate toward the tool insertion port along the axial direction of the slide shaft. A member is provided,
Wherein the closure plate, prior Symbol than said closure portion adjacent the full closure portion fitted in the tool insertion port barrier projection is provided in a position which is the center side of the lid body,
When the closing plate is lowered by the pressing of the plug portion, the barrier protrusion is located on the center side of the lid body from the tool insertion port and is located on the upper side closer to the back surface of the lid body than the plug portion. A structure for locking a lid for an underground structure, characterized in that On the back surface of the lid body, a recess is formed adjacent to the tool insertion slot to engage the tip of a predetermined tool at a position closer to the center side of the lid body than the tool insertion slot. 2. The underground structure lid locking structure according to claim 1, wherein when the tool insertion port is closed by the fitting of the plug portion, the barrier protrusion enters the concave portion.

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