JP3430249B2 - Locking device for manhole cover - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manhole cover locking device.

[0002]

2. Description of the Related Art As a locking device of this type, for example, one shown in FIG. 6 is known (Japanese Utility Model Laid-Open No. 63-198638). There, the lock piece 40 is hung on the inner surface of the manhole cover 4 so as to be swingable around a shaft 41, and the lock piece 40 is engaged with a receiving portion 42 provided on the receiving frame 2 side by its own weight, thereby concentrating. The manhole cover 4 is prevented from unexpectedly rising or popping out and opening due to abnormal pumping pressure such as during heavy rain or gas pressure generated in the manhole. And
At the time of unlocking, the key 26 such as a bar is inserted into the key hole 25 of the manhole cover 4 and the head 40a of the lock piece 40 is pressed to swing the lock piece 40 in the releasing direction against its own weight. It moves to release the engagement state with the receiving portion 42.

[0003]

In the above-mentioned conventional example, the tapered surface 6 having a gradually decreasing diameter is formed on the inner circumference of the receiving frame 2 while the outer peripheral surface 7 of the manhole cover 4 is formed on the tapered surface 6. It is formed in a taper shape that is in surface contact with. Therefore, when the manhole cover 4 is closed, the outer peripheral surface 7 of the manhole cover 4 does not fit into the inner periphery of the receiving frame 2 with a gap, and rainwater does not enter from the location.

However, the key hole 25 is the head 4 of the lock piece 40.
Although it is in a state of being closed by 0a, the head 40a of the lock piece 40 and the key hole 2 are provided in order to ensure the rocking of the lock piece 40.
Since it is necessary to form a gap between the key hole 2 and
No. 5 is not completely blocked and is in communication with the inside of the manhole. Therefore, the head 40a of the lock piece 40 and the key hole 25
Rainwater and sand enter the manhole through the gap. In particular, if the amount of sewage water in a manhole increases due to intrusion of rainwater during heavy rain, it will exceed the capacity of the treatment tanks and pumps at the final treatment plant, resulting in inability to treat, or an increase in treatment costs as the amount of treated water increases. Will be done. As a measure for preventing rainwater and sand from entering through the key hole 25, it has been proposed to close the key hole 25 of the manhole cover with a rubber cap. However, when gas is generated in the manhole, this gas pressure This was not enough because the cap would come out with.

Therefore, the object of the present invention has been made in view of such a situation, and rainwater can be surely prevented from entering by devising a waterproof structure around the key hole of the manhole cover and the latch. It is to provide a locking device for a manhole cover.

[0006]

According to the present invention, as shown in FIG. 1, a manhole cover 4 is fitted into an annular receiving frame 2 via a hinge mechanism 5 so as to be openable and closable, and is mounted inside the upper end of the receiving frame 2. A tapered surface 6 having a diameter gradually decreasing downward is formed on the circumference, and an outer peripheral surface 7 of the manhole cover 4 is formed in a tapered shape in surface contact with the tapered surface 6, and a hinge mechanism in the manhole cover 4 is formed. Provided on part of the outer circumference on the side opposite to
In the locking device to be installed, it is mounted on the manhole cover 4 side.
Latch 14 and a receiving recess provided in a part of the inner circumference of the receiving frame 2.
And a section 15. The latch 14 has a substantially rectangular flat shape.
It is formed in a plate shape and is inclined at the corner where the tip surface and the bottom surface intersect.
A surface 16 is formed on one side of the latch 14 to receive the key.
A recess 17 is formed. Outer surface of manhole cover 4
In a part of 7, there is a recess 19 for receiving the latch 14.
It is provided so as to face the receiving concave portion 15 of the receiving frame 2 and open.
Has been. The bottom side of the recess 19 is inside the manhole cover 4.
It is closed by the bottom wall 20 that is integrally formed in a bulge shape downward from the surface.
The inside of the recess 19 and the inside of the manhole opening 1 are the bottom wall 2
It is blocked by 0. The outer peripheral surface 21 of the bottom wall 20 is formed in a tapered shape that is flush with the outer peripheral surface 7 of the manhole cover 4 ,
When the hole cover 4 is fitted into the receiving frame 2,
The taper surface 6 is brought into close contact with the taper surface 6 . Luck
The bottom surface of the switch 14 has a groove elongated in the radial direction of the manhole cover 4.
22 is provided, and the groove 22 is provided with a stopper protruding from the bottom wall 20.
By fitting the tip of the par pin 23, the tip of the latch 14
The position where the end projects from the recess 19 and retracts into the recess 19
Latch 14 reciprocates linearly in recess 19 over position
It is movably incorporated and has a rear end and a recess in the latch 14.
Between the inner back wall of 19 and the tip of the latch 14,
A spring portion that engages with the receiving concave portion 15 and urges it in a protruding direction.
The material 24 is accommodated, and the manhole cover 4 is placed in the receiving frame 2.
At the time of fitting, the slope 16 of the latch 14 is located inside the receiving frame 2.
When the latch 14 hits the upper edge of the circumference,
To be pulled into the recess 19 against the force of the bed member 24
I am doing it. On the upper surface of the manhole cover 4 near the outer circumference
Has a key hole 25 having a key receiving recess 17 of the latch 14.
The lower end of the rod 27
The key 26 is provided with the key piece 28, and the key piece 28 is pressed.
-Put it in the recess 19 from the hole 25 and
By rotating, the key piece 28 receives the key of the latch 14.
After engaging with the recessed portion 17, the latch 14 is attached to the spring member 24.
It can be withdrawn against the force, and the key piece 28 receives the key
In the state where the key piece 28 is engaged in the recess 17, the key piece 28 is
It is characterized in that it is engaged with the inside of 5 in a manner that it does not come out upward .

[0007]

[0008]

[Action] By engaging the latch 14 of the manhole cover 4 side receiving frame 2 side of the receiving recess 15, it is possible to lock the manhole cover 4 to receive frame 2, thus Ya pressure of the manhole cover 4 is in the manhole It is possible to prevent the gas from jumping out. The engaged state of the latch 14 can be unlocked by inserting the key 26 into the key hole 25 and operating the latch 14 in the releasing direction.

A bottom wall 20 is provided in the recess 19 of the manhole cover 4, and an outer peripheral surface 21 of the bottom wall 20 is formed in a tapered shape which is flush with the outer peripheral surface 7 of the manhole cover 4 to form an inner periphery of the receiving frame 2. Since the surface comes into close contact with the surface, rainwater will come from the key hole 25 to the recess 1
Even if it enters the inside 9, it does not penetrate into the manhole from the recess 19.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) FIG. 1 is an overall cross-sectional view showing a locking device for a manhole cover according to the present invention, FIG. 2 is a plan view of an essential part, and FIG. 3 is A in FIG.
-A line sectional view, FIG. 4 is a BB line sectional view in FIG. 3, and FIG. 5 is a partial front view of the key. In FIG. 1, 1 is a manhole port, 2 is a cast iron annular receiving frame installed in the manhole port 1 with anchor bolts 3, 4 is a cast iron disc-shaped manhole cover fitted in the receiving frame 2, and has a hinge. It is mounted on the receiving frame 2 via the mechanism 5 so as to be swingable and openable and detachable.

A taper surface 6 is formed on the inner periphery of the upper end of the receiving frame 2 so as to have a diameter gradually decreasing downward. The outer peripheral surface 7 of the manhole cover 4 is formed in a tapered shape so as to make surface contact with the tapered surface 6 without any clearance. A hinge mechanism 5 for connecting the manhole cover 4 to the receiving frame 2 so as to be swingably opened / closed and detachable is provided with a hinge 9 on a part of the lower surface of the manhole cover 4 near the outer periphery.
The upper end of the manhole cover 4 is pivotally mounted around the shaft 10 so as to be swingable in the radial direction of the manhole cover 4. At the lower end of this hinge 9 is a protrusion 11
Is provided in parallel with the shaft portion 10. Then, a hinge retaining ring 13 having an elongated hole 12 in the radial direction of the receiving frame 2 is projected on a part of the inner periphery of the receiving frame 2, and a projection 11 at the lower end of the hinge 9 is crossed with the hole 12 of the hinge retaining ring 13. Through.

A locking device is provided on a part of the outer periphery of the manhole cover 4 opposite to the hinge mechanism 5. This locking device will be described with reference to FIGS. 2 to 4. This locking device includes a latch 14 mounted on the manhole cover 4 side.
And a receiving recess 15 provided in a part of the inner periphery of the receiving frame 2. The latch 14 is formed in a substantially rectangular flat plate shape,
An arc or flat slope 16 is formed at the corner where the tip surface and the bottom surface intersect, and a key receiving recess 17 is formed on one side surface. The latch 1 is provided on a part of the outer peripheral surface 7 of the manhole cover 4.
A recess 19 for housing 4 is provided so as to face the receiving recess 15 of the receiving frame 2 and open. This recess 19
The bottom side of the manhole cover 4 is closed by a bottom wall 20 integrally formed so as to bulge downward from the inner surface of the manhole cover 4, and the interior of the recess 19 and the interior of the manhole opening 1 are blocked by the bottom wall 20. . The outer peripheral surface 21 of the bottom wall 20 is formed in a tapered shape that is flush with the outer peripheral surface 7 of the manhole cover 4, and when the manhole cover 4 is fitted into the receiving frame 2, it is similar to the outer peripheral surface 7 of the manhole cover 4. In addition, the taper surface 6 of the receiving frame 2 is brought into surface contact.

On the lower surface of the latch 14, an elongated groove 22 is provided in the radial direction of the manhole cover 4, and the tip of a stopper pin 23 projecting from the bottom wall 20 is fitted into this groove 22, whereby the tip of the latch 14 is fitted. The latch 14 is linearly reciprocally installed in the recess 19 so that the latch 14 extends from the recess 19 and retracts into the recess 19. A spring member 24 is interposed between the rear end of the latch 14 and the inner back wall of the recess 19, and the spring action constantly biases the latch 14 in the protruding direction.

When the manhole cover 4 is fitted in the receiving frame 2 by rotating in the closing direction with the hinge mechanism 5 as a fulcrum, the latch 1
The slope 16 at the tip of 4 hits the upper end of the inner circumference of the receiving frame 2, and the latch 14 retracts into the recess 19 against the force of the spring member 24 by the component force of the fitting force, and the manhole cover 4 fixes the outer peripheral surface 7 of the same. When completely closed so as to make surface contact with the tapered surface 6 on the inner circumference of the receiving frame 2, the receiving recess 15 of the receiving frame 2 and the recess 19 are aligned, so that the latch 14 projects and moves by the restoring force of the spring member 24. A locked state that engages in the recess 15 is obtained.

An oval key hole 25 is opened at a portion near the outer periphery of the upper surface of the manhole cover 4 so as to correspond to the upper side of the latch 14 where the key receiving recess 17 is provided. Figure 5
As shown in FIG. 4, the key 26 is provided with an oval key piece 28 at a right angle at the lower end of the rod 27. When using, the key piece 28 is inserted from the key hole 25 into the recess 19 as shown in FIG. Rotate 90 degrees around the axis. This key 26
When one end of the key piece 28 is engaged with the key receiving recessed portion 17 of the latch 14 by the turning operation of the.
It is possible to retreat against the force of No. 4 and the engagement with the receiving recess 15 is released with this retreat. Also, this key 2
6 can also be used as a jig for lifting the manhole cover 4. That is, when the key piece 28 is engaged with the key receiving recess 17, the key piece 28 is engaged in the inside of the key hole 25 so as to prevent the key piece 28 from slipping upward. Can be opened and rotated using the hinge mechanism 5 as a fulcrum.

In the normal state, the key hole 25 is closed by detachably fitting an elastic cap 29 such as rubber as shown in FIG. 3, whereby rainwater or sand flows from the key hole 25 into the recess 19. Can be prevented from entering. The cap 29 is pulled out from the key hole 25 only when the manhole cover 4 is opened using the key 26.

[0017]

[0018]

[0019]

[0020]

According to the present invention, although the concave sites 19 of the order was <br/> housing the latches 14 is provided on the manhole cover 4, the bottom side of the recess 19 is closed by a bottom wall 20 At the same time, the outer peripheral surface 21 of the bottom wall 20 is formed in a tapered shape that is flush with the outer peripheral surface 7 of the manhole cover 4, so that the tapered surface 6 of the receiving frame 2 comes into close contact with the tapered surface 6. Therefore, rainwater is keyhole 2
Even if it enters the recess 19 from 5, the bottom wall 20 can prevent the water from entering into the manhole, and the outer peripheral surface 7 of the manhole cover 4 and the tapered surface 6 of the receiving frame 2 which are taper-fitted to each other can be prevented. The effect of preventing rainwater intrusion into the manhole can be fulfilled in combination with the function of preventing rainwater intrusion from inside, and the amount of wastewater in the manhole increases and the treatment at the final disposal site of wastewater in the manhole becomes impossible. It is possible to solve such problems.

[Brief description of drawings]

FIG. 1 is an overall sectional view showing a first embodiment.

FIG. 2 is a plan view of a main part.

3 is a cross-sectional view taken along the line AA in FIG.

FIG. 4 is a sectional view taken along line BB in FIG.

FIG. 5 is a front view of a part of the key.

FIG. 6 is a sectional view of a main part of a conventional example.

[Explanation of symbols]

2 receiving frame 4 manhole cover 5 Hinge mechanism 6 Tapered surface of receiving frame 7 Outer surface of manhole cover 14 Latch 15 Receiving recess 16 Latch slope 19 recess 20 bottom wall 21 Outer peripheral surface of bottom wall 24 Spring member 25 key hole 26 keys 29 caps

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) E02D 29/14

Claims (2)

(57) [Claims] 1. A manhole cover 4 is fitted into a ring-shaped receiving frame 2 via a hinge mechanism 5 so as to be openable and closable, and a taper surface is formed on the inner periphery of the upper end of the receiving frame 2 such that the diameter gradually decreases downward. 6 is formed, and the outer peripheral surface 7 of the manhole cover 4 is formed in a tapered shape that is in surface contact with the tapered surface 6, and is provided on a part of the outer periphery of the manhole cover 4 opposite to the hinge mechanism 5. In the device, the latch 14 mounted on the manhole cover 4 side and the receiving frame 2
The latch 14 is provided in a part of the inner circumference, and the latch 14 is formed in a substantially rectangular flat plate shape.
A slope 16 is formed at the corner where the tip surface and the bottom surface intersect.
The key receiving recess 17 is formed on one side of the latch 14.
The latch 14 is housed in a part of the outer peripheral surface 7 of the manhole cover 4.
The receiving recess 19 faces the receiving recess 15 of the receiving frame 2.
Provided to open me, the bottom side of the recess 19, downward from the inner surface of the manhole cover 4
Is closed by a bottom wall 20 that is integrally formed in a bulge shape to form a recess 1
The inside of the manhole opening 9 is cut off from the inside of the manhole opening 1 by the bottom wall 20, and the outer peripheral surface 21 of the bottom wall 20 is formed in a tapered shape flush with the outer peripheral surface 7 of the manhole cover 4. The manhole cover 4 and the receiving frame 2
When it is fitted inside, the taper surface 6 of the receiving frame 2 is in close contact with the tapered surface 6, and the lower surface of the latch 14 is elongated in the radial direction of the manhole cover 4.
A groove 22 is provided, and a groove provided from the bottom wall 20 is provided in the groove 22.
By fitting the tip of the topper pin 23, the latch 14
The position where the tip of the protrusion protrudes from the recess 19 and retreats into the recess 19.
The latch 14 linearly in the recess 19
It is incorporated so that it can reciprocate, and the latch 14 is provided between the rear end of the latch 14 and the inner back wall of the recess 19.
14 projecting laterally this tip is engaged in the recess 15 receives the normal
A spring member 24 for urging and pushing in the direction is housed, and when the manhole cover 4 is fitted into the receiving frame 2, the latch 14 is inserted.
The slant surface 16 of the abutment 16 hits the upper end of the inner periphery of the receiving frame 2 and
The component force of the force causes the latch 14 to resist the force of the spring member 24.
The manhole cover 4 is drawn into the place 19, and the keyhole 25
Is located above the side of the latch 14 having the key receiving recess 17
The key 26 is provided with a key piece 28 at the lower end of the rod 27, and the key piece 28 is inserted into the recess 19 from the key hole 25 and the rod 27 is inserted.
By pivoting around the axis of the key piece 28,
After engaging the key receiving recess 17 of the switch 14,
It can be retracted against the force of the spring member 24, and when the key piece 28 is engaged in the key receiving recess 17, the key is not pressed.
-The piece 28 is engaged inside the key hole 25 so that it does not come out upward.
Locking device of the manhole cover, characterized in that it is if. 2. The key hole 25 has an elastic cap 29.
The locking device for a manhole cover according to claim 1 , wherein the locking device is detachably closed with a .