JP3653420B2 - Manhole cover locking device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manhole cover that leads to a common groove through a gas pipe or a telecommunication cable, or to a sewer or other underground pipe, and more particularly to a locking device that prevents the manhole cover from opening unexpectedly.
[0002]
[Prior art]
The manhole leading to the common ditch, sewer and other underground pipes is closed at the top by a lid, but the manhole lid should not be opened suddenly due to rupture of underground objects or rising water level. It is customary to provide a locking device on the back side.
[0003]
The locking device is swingable on the back of the manhole cover as disclosed in Japanese Utility Model Publication Nos. 60-7418, 62-159560, 7-56357, 8-6115. It is configured based on a pendulum called a lock to be attached, a locking rod, etc., and the collar part formed on the pendulum is a part of the inner periphery of the cylindrical receiving frame (lock holder) that forms the upper structure of the manhole by the weight of the pendulum It is designed to engage. And according to these locking devices, a pendulum can be rock | fluctuated and locking can be cancelled | released by inserting a bar etc. in the tool insertion port formed in the periphery of a manhole cover.
[0004]
[Problems to be solved by the invention]
However, many of the conventional locking devices are designed so that the buttocks correspond to the receiving frame only by the weight of the pendulum, so that when the pressure in the manhole rises, the pendulum swings due to the pressure and the locking is released naturally. There was a fear of making it.
[0005]
In addition, as a pendulum that forms the base of the locking device, as in Japanese Utility Model No. 8-6115, the tool insertion port is closed when the lid is closed to prevent the inflow of water and earth and sand into the manhole, and the pendulum is opened when the lid is opened. Some plug parts (open / close valves) that have a function as a swinging operation part are integrally formed, but according to this type of pendulum, the plug part is formed close to the fulcrum of the pendulum. The plug part moves in a small circular orbit around the pivot point of the pendulum. For this reason, it is necessary to secure the operating range of the plug part by making the plug part smaller than the tool insertion slot or by cutting out the inner peripheral surface of the receiving frame, etc. Since it becomes imperfect, water and earth and sand easily flow into the manhole. If the pendulum fulcrum is moved closer to the center of the manhole cover in order to eliminate the above-mentioned drawbacks, the protruding amount of the buttock and the plug must be increased. Since a large rotational moment is generated to swing the tool in the opposite direction, the closing force of the tool insertion port by the plug portion is weakened.
[0006]
In this regard, in Japanese Utility Model Publication No. 7-56357, a stopper (blocking plate) is integrally attached to a pendulum (locking rod) via an elastic body made of sponge rubber so that the stopper is lowered while the elastic body is contracted. Therefore, it is not necessary to secure the operation area of the plug part in the receiving frame, and it is possible to seal the tool insertion port, but this kind of pendulum is subjected to various processing to attach an elastic body and plug part to the part This requires a complicated structure with a large number of parts and a high cost.
[0007]
The present invention has been made in view of the circumstances as described above, and an object of the present invention is to provide a simple manhole cover locking device capable of sealing a tool insertion slot with an extremely simple structure. is there.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a manhole cover having a tool insertion opening on the periphery and fitted to the upper opening of the receiving frame, and swings on the back surface of the manhole cover in the vicinity of the tool insertion opening. A locking device including a pendulum that is suspendably supported, and a pendulum for locking corresponding to an inner peripheral portion of the receiving frame and a pivot that forms a fulcrum for swinging. valve plate for closing the tool insertion opening between the lid is device with swingable, the valve plate is engaged with the projection end and the pendulum was separately is formed on the back surface of the manhole cover While swinging around the protrusion, a plug portion corresponding to a tool insertion port is formed at the other end of the valve plate, and the plug portion is placed in the tool insertion port between the valve plate and the pendulum. A curved spring that urges the flange toward the position corresponding to the portion of the inner periphery of the receiving frame while pushing toward The spring is deformed when the upper surface of the plug part is pressed from the tool insertion port, and both ends are locked to the parts of the pendulum and the valve plate so that the pendulum can be swung toward the opposite side of the hook part. The present invention provides a locking device for a manhole cover.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, application examples of the present invention will be described in detail with reference to the drawings. First, FIG. 1 is a partially broken view showing a state where a manhole is covered. In the figure, reference numeral 1 denotes a cylindrical receiving frame that forms the upper structure of a manhole. The receiving frame 1 is connected to an opening edge of a shaft not shown in the figure, and is embedded so that the upper surface matches the road surface. The upper surface opening 2 is a tapered hole that narrows downward, and a lock receiver 3 that protrudes downward is integrally formed on the inner periphery. 4 is a circular manhole cover that fits into the upper surface opening, and a semi-circular tool insertion hole 5 is formed on the periphery of the lid, and a tool insertion opening is formed on the rear surface. A notch groove 6 is formed adjacent to 5.
[0010]
Note that a part of the periphery of the lid 4 is linked to the receiving frame 1 by a hinge fitting (not shown) mounted on the back surface of the lid 4, and the tool insertion port 5 facing the hinge fitting is positioned above the lock receptacle 3 when the lid is closed. It is like that. The locking device according to the present application is mounted on the back surface of the lid 4 in the vicinity of the tool insertion slot 5. The apparatus includes a pendulum 7 that is swingably supported on the back surface of the lid 4, a valve plate 8 that is swingably provided between the pendulum 7 and the lid 4, and the valve plate 8 and the pendulum 7. And a spring 9 interposed between them. And according to the locking device which concerns on this application, the tool insertion port 5 is sealed by the valve plate 8 at the time of a lid closing, and when opening a lid, as shown in FIG. 2, with tools T, such as a bar inserted in the tool insertion port 5. The pendulum 7 is swung while the valve plate 8 is pushed down so that the collar portion 10 is separated from the lock receiver 3.
[0011]
As apparent from FIGS. 3 and 4, the pendulum 7 has a pair of arms 11 extending upward from both sides thereof, and forms a fulcrum when swinging horizontally from the upper end of each arm 11. A pivot 12 is formed. A locking claw 13 that contacts the back surface of the lid 4 is formed on the top of the pendulum 7 along the inner side of each arm portion 11 from the tip to the rear and upward. A flange 10 corresponding to the receiver 3 is formed.
[0012]
As shown in FIG. 5, the pendulum 7 is supported by a pivot 12 by a circular groove 14A of a bracket 14 formed on the back surface of the lid 4 with the tool insertion slot 5 interposed therebetween. It can be swung.
[0013]
On the other hand, the valve plate 8 is a rectangular member having a certain length as apparent in FIG. 6, one end of which is a bent locking portion 16 having a loose hole 15, and the other end is an upper portion of a tool. A semi-conical plug portion 17 that fits into the insertion port 5 is projected.
[0014]
Here, the pendulum 7 and the valve plate 8 are removably assembled to the back surface of the lid 4 via a spring 9 curved in a U-shape as shown in FIG. Among these, as shown in FIG. 5, the pendulum 7 is supported by the pivot shaft 12 formed at the upper part thereof being fitted to the circular groove 14A of the bracket, thereby enabling swinging in the direction of the arrow shown in FIG. .
[0015]
Note that the pendulum 7 hangs down from the back surface of the lid 4 directly below the lid 4 due to its own weight as shown in FIG. 1 so that the collar portion 10 faces the lock receiver 3 of the receiving frame 1. On the other hand, the valve plate 8 passes between the arm portions 11 of the pendulum 7, and one end thereof is engaged with a protrusion 18 formed on the back surface of the lid 4. That is, the valve plate 8 is positioned by allowing the protrusion 18 to pass through the loose hole 15, and at this time, the plug portion 17 formed at the other end is introduced into the inside of the tool insertion port 5 from below the tool insertion port 5. 5 is sealed.
[0016]
As apparent from FIG. 5, the valve plate 8 interferes with the pendulum 7 because its width is narrower than the width of the concave groove 20 formed between the locking claws 13, 13 of the pendulum 7. The valve plate 8 and the pendulum 7 are interlocked through a spring 9 interposed therebetween. Further, the bottom surface of the valve plate 8 is prevented from falling off by being supported by the spring 9, and when the upper surface of the plug portion 17 is pressed from the tool insertion port 5, the spring 9 is deformed and swings around the protrusion 18. Will move.
[0017]
Here, the spring 9 is a plate spring curved in a U-shape, which is press-fitted into an air space formed between the lower surface of the valve plate 8 and the bottom 20A of the concave groove 20, and both ends thereof are respectively valve plates. 8 and the pendulum 7 are locked. In particular, the spring 9 has a lower jaw piece 9 </ b> A extending from the front of the bottom 20 </ b> A of the concave groove 20 toward the upper rear part thereof and an upper jaw piece 9 </ b> B extending along the lower surface of the valve plate 8, and the front side of the pendulum 7 is opened. . Further, a groove 21 for locking one end on the lower side of the spring 9 is formed on the bottom 20A of the concave groove 20 of the pendulum 7, and one end on the upper side of the spring 9 is locked on the lower surface of the valve plate 8. A groove 22 is formed. In particular, each of the grooves 21 and 22 is formed so as to be positioned in front of the fulcrum of the pendulum 7 (center side of the lid 4), and the spring 9 has elasticity in a direction in which both ends expand to each other, 22 is crimped.
[0018]
Thus, according to the spring 9, the pendulum 7 is urged toward the flange 10 by the lower jaw piece 9 </ b> A, and the valve plate 8 is urged toward the lid 4 by the upper jaw piece 9 </ b> B so that the plug portion 17 is moved to the tool. It acts to push into the insertion port 5. Accordingly, the collar portion 10 is maintained at the position corresponding to the lock receiver 3 without being swayed by the weight of the pendulum 7 and the elasticity of the spring 9 when the lid is closed, and hence the lid 4 is caused by the pressure increase in the manhole. Sudden opening can be prevented. Further, when the lid is closed, the plug portion 17 is pushed in by the spring 9 from the lower side to seal the tool insertion port 5, so that it is possible to prevent rainwater and earth and sand from flowing into the manhole from the tool insertion port 5.
[0019]
Here, in order to open the lid 4, it is sufficient to pull up the peripheral edge of the lid 4 using a bar or other tool T. That is, as shown in FIG. 2, a tool T such as a bar is inserted from the tool insertion port 5, and the lid 4 is pulled up while the tip is directed to the notch groove 6. At this time, the plug portion 17 will be detached from the tool insertion opening 5 is found depressed by the tool T. That is, since the upper surface of the plug portion 17 is pressed by the tool T, the valve plate 8 swings about one end side as a fulcrum against the elasticity of the spring 9. As a result, the pendulum 7 is swung to the opposite side of the flange portion 10 through the spring 9. That is, the spring 9 is deformed by pressing the upper jaw piece 9B by swinging the valve plate 8, and acts to push up the portion of the pendulum 7 at the lower end thereof in the direction of the arrow shown in the figure. Thereby, since the collar part 10 is separated from the lock receiver 3 and the locking of the lid 4 is released, the lid 4 can be opened.
[0020]
On the other hand, when the lid 4 is placed again on the upper surface opening 3 of the receiving frame 1 at the end of the inspection in the manhole and the tool T is removed from the tool insertion port 5 thereafter, the pressing force against the plug 17 disappears, and the spring 9 The valve plate 8 is pressed against the back surface of the lid 4 while restoring. For this reason, the plug part 17 fits into the tool insertion slot 5 and seals the tool insertion slot. At this time, the pendulum 7 swings toward the flange portion 10 by its own weight and the elasticity of the spring 9, and the flange portion is returned to a position corresponding to the lock receiver 3. As is apparent from FIG. 7, the pendulum 7 is restricted from swinging toward the flange 10 when the tip of the locking claw 13 comes into contact with the back surface of the lid 4. 9 has a predetermined elasticity even during restoration and does not come off between the pendulum 7 and the valve plate 8.
[0021]
As mentioned above, although the suitable example of this invention was demonstrated based on drawing, the locking device concerning this invention is not restricted to the said example, For example, a torsion spring other than a leaf | plate spring can also be used as the spring 9. FIG.
[0022]
【The invention's effect】
As is clear from the above description, according to the present invention, the collar portion of the pendulum is biased toward the position corresponding to the inner peripheral portion of the receiving frame by the spring interposed between the pendulum and the valve plate. As a result, the pendulum does not hang when the pressure in the manhole rises, and the collar does not come off the position corresponding to the inner peripheral portion of the receiving frame, and functions effectively as a locking device.
[0023]
Furthermore, since the valve plate is urged toward the lid by a spring and the plug portion is pushed into the tool insertion port, the tool insertion port can be tightly closed to prevent water from entering the manhole. .
[0024]
Further, the locking device according to the present invention has a simple structure with a small number of parts as described above, and thus can be made at low cost, and the valve plate is separated from the pendulum so that the valve plate can be separated from the fulcrum of the pendulum. It can be set to swing regardless. Accordingly, the track of the plug portion in the vicinity of the tool insertion port can be made substantially linear, and as a result, the tool insertion port can be sealed without leaving the plug portion, and the sealing performance can be greatly improved.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view showing a state in which a top opening of a receiving frame is closed by a manhole cover equipped with a locking device according to the present invention. FIG. 2 is a partial cross-sectional view showing a state in which the manhole cover is opened. Side view of the pendulum [Fig. 4] Perspective view of the pendulum [Fig. 5] Partial sectional view of the pendulum suspended from the back surface of the lid [Fig. 6] Perspective view of the valve plate [Fig. 7] Schematic side view showing the state suspended from the back [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Receiving frame 2 Upper surface opening of receiving frame 3 Lock receiving 4 Manhole cover 5 Tool insertion port 7 Pendulum 8 Valve plate 9 Spring 10 Hook 12 Axle 13 Locking claw 14 Bracket 15 Loose hole 17 Plug part 18 Protrusion 20 Concave groove 21 22 groove

Claims (1)

In a manhole cover that has a tool insertion port on the periphery and is fitted to the upper surface opening of the receiving frame, including a pendulum that is swingably supported on the back surface of the manhole cover in the vicinity of the tool insertion port, A locking device in which the pendulum forms a locking collar corresponding to the inner peripheral portion of the receiving frame and a pivot that forms a fulcrum when swinging ,
A valve plate that closes the tool insertion slot is swingable between the pendulum and the manhole cover, and the valve plate is separated from the pendulum and has one end formed on a protrusion formed on the back surface of the manhole cover. and engagement with swings around the projection, the other end of the valve plate stopper portion is formed corresponding to the tool insertion port, between the valve plate and the pendulum, the stopper portion A curved spring that urges the flange toward the position corresponding to the inner peripheral portion of the receiving frame while pushing it into the tool insertion slot is interposed, and the spring extends from the tool insertion opening to the upper surface of the plug section. An apparatus for locking a manhole cover, characterized in that both ends are engaged with the pendulum and the valve plate so that the pendulum can be swung toward the opposite side of the flange while being deformed when pressed.

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