JP4125438B2 - Manhole cover frame locking structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of a manhole provided on a road or the like, and more particularly to a structure of a portion for locking a lid plate to a manhole frame so as to be opened and closed.
[0002]
[Prior art]
The manhole is provided on the ground surface as an entrance for workers when repairing and checking underground facilities. The surface of the manhole is formed by a manhole frame and a cover plate, and is closed with a cover plate whose outer periphery is a cone outer peripheral surface fitted in the inner peripheral surface of the upper end inner periphery of the manhole frame. When an operator enters or exits the manhole, the lid plate must be opened. As shown in FIGS. 4, 5, 6, 7, 8, and 9, the lid plate is normally opened and closed using a bar (lever bar) having pins protruding on both sides of the tip. A lid that is tightly closed by fitting the conical surfaces together by inserting the tip of a bar into a lever insertion hole provided near the outer periphery of the lid plate, hooking the pin 20a to the back surface of the lid plate, and utilizing the lever action The cover plate is lifted by lifting the plate and then lifting the tip of the bar, and the cover plate is opened by shifting the cover plate to the side or turning it 180 degrees.
[0003]
The lid plate is firmly fitted to the manhole frame by fitting the conical circumferential surfaces, so it cannot be removed easily, but when the internal pressure of the manhole rises for some reason, the lid is removed. May jump up. In order to avoid this, the cover plate is normally loosely engaged by a hook provided on the lower surface thereof and a hook provided on the inner periphery of the manhole frame, and when the internal pressure of the manhole rises, the cover plate is lifted up slightly and the manhole frame The pressure is released from the gap.
[0004]
When opening the cover plate, it is necessary to disengage the hook from the hook. Therefore, one of the hooks usually provided one by one in the diametrically opposed position of the lid plate is a pendulum type hook, and when the bar is inserted into the lever insertion hole, the pendulum type hook swings at the end of the bar. Thus, the engagement with the flange on the inner periphery of the manhole frame is released. A conventional pendulum type hook is suspended from the lower surface of the cover plate by a tangential fulcrum shaft, or is suspended so as to swing around an oblique fulcrum pin inclined by 45 degrees with respect to the tangent. These pendulum-shaped hooks are usually provided with a closing plate integrally, and in the state where the pendulum-shaped hook is naturally suspended, that is, the pendulum-shaped hook is inserted below the flange of the manhole frame, Is in contact with the lower side of the lever insertion hole to close the lever insertion hole. When the tip of the bar is inserted into the lever insertion hole, the closing plate is pushed downward, and this movement is used to swing the pendulum hook around the fulcrum shaft so that the pendulum hook and hook are disengaged. is there.
[0005]
[Problems to be solved by the invention]
However, this type of conventional engaging structure swings the pendulum hook to the inner peripheral side of the cover plate and disengages the pendulum hook from the hook, so that the pendulum hook is suspended. It is necessary to place a lever insertion hole and a closing plate in a narrow part outside the fulcrum shaft, and in order to swing the pendulum hook to the outer peripheral side in a free state, a weight is provided on the inner peripheral side of the pendulum hook There was a problem that the structure was complicated, such as the need to do.
[0006]
The lid plate is made strong enough to withstand the weight of a large vehicle traveling on it, and is therefore heavy, and it should be firmly fitted to the manhole frame by the mutual fitting of the conical circumferential surfaces described above. For this reason, a large force is required for opening and closing, and an impact is often applied to loosen the fitting, and it is often handled violently. Therefore, it is necessary to give sufficient strength to the above-mentioned pendulum type hooks, etc., and there are many unreasonable things to put them in the narrow space on the outer periphery of the lid plate, which is the shape of the pendulum type hooks. It has become a cause of increasing the cost of manholes by complicating the above.
[0007]
The present invention provides a manhole cover plate locking structure that can open and close the cover plate with the same simple operation as before, has sufficient strength, and can reduce the cost of the cover plate. Is an issue.
[0008]
[Means for Solving the Problems]
In the manhole cover locking structure of the present invention, the conical inner peripheral surface 4 formed on the inner periphery of the upper end of the manhole frame 2 and the conical outer peripheral surface 6 of the cover plate 5 are fitted to each other so that the cover plate 5 is attached to the manhole frame 2. The lid plate 5 includes a lever insertion hole 18 provided at one location near the outer periphery thereof, and a pendulum suspended in a swingable manner around the fulcrum shaft 17 at a lower portion of the lever insertion hole 18. A hook 14 and a closing plate 14b extending substantially horizontally in the same direction as the key 14a at the tip of the pendulum hook 14 from the fulcrum shaft 17 portion integrally with the pendulum hook 14 are provided on the inner periphery of the manhole frame 2. The lock 14 includes a fixed locking portion 19 to which the key 14a is locked, and the key 14a is inserted below the locking portion 19 in a state where the pendulum hook 14 is naturally suspended, and the closing plate 14b is connected to the lever insertion hole 18. In the locking structure of the manhole cover plate that closes the Provided fulcrum shaft 17 of the hook 14 in the radial direction of the cover plate 5 is provided with an engaging portion 19 projecting radially on the inner periphery of the manhole frame 2. The lever insertion hole 18 is preferably formed as an elongated hole elongated in the radial direction of the cover plate 5, and the upper surface portion of the cover plate 5 connected to the outer peripheral side end of the long hole is preferably formed lower than the upper surface 2 a of the manhole frame. .
[0009]
The manhole cover plate locking structure according to claim 1 of the present application is the manhole cover plate locking structure provided with the above-described means, and one manhole facing the lower surface of the outer peripheral portion of the cover plate 5. On the inner peripheral surface of the frame 2, a positioning projection 21 having a V-shaped cross section having a ridge line in the radial direction of the cover plate 5 and a receiving projection 22 provided with a V-shaped groove 22 a that fits the V shape of the positioning projection 21. The positioning pair is integrally formed to project.
[0010]
The manhole cover plate locking structure according to claim 2 of the present application is the manhole cover plate locking structure provided with the above means, and the cover plate facing the mounting position of the pendulum hook 14 in the diameter direction. A guide bar 10 bent in an arc around the tangential fulcrum shaft 9 and having an inverted T-shaped locking end formed at the tip is suspended from the lower surface of the outer peripheral side of the outer peripheral side 5 and the guide bar 10 is provided on the manhole frame 2 side. A fixed flange 7 that is formed in the inner peripheral surface of the manhole frame 2 so as to penetrate the elongated hole 11 in the radial direction and close to the guide bar 10, and a sufficient gap below the fixed flange 7 in the radial direction A cover plate 5 having a tip inserted from the inside and a fixed hook 8 integrated therewith are provided.
[0011]
In the structure of the present invention, the pendulum hook 14 swings in the tangential direction of the cover plate 5. Therefore, a sufficient space is obtained in the front-rear direction of the swing, the position of the lever insertion hole 18 and the dimensions of the closing plate 14b can be freely designed, and the pendulum hook 14 and the locking portion 19 have sufficient strength. Can be dimensioned.
[0012]
The cover plate 5 is normally locked to the manhole frame 2 with a loose hinge structure at a position facing the pendulum hook 14 in the diameter direction. Therefore, the circumferential position of the cover plate 5 is defined to some extent. If the dimension of the key 14a at the tip of the pendulum hook 14 is increased, the engagement with the locking portion 19 is possible even if the cover plate 5 is slightly rotated. Will not come off. However, in order to ensure a more reliable engagement between the pendulum-type hook 14 and the locking portion 19 and to ensure smooth workability when the lid plate 5 is opened and closed, the lid plate 5 must be positioned more accurately. Is preferred. The invention of claim 1 has a simple structure for positioning the cover plate 5 on the manhole frame 2 in the circumferential direction. When the cover plate 5 is closed, the positioning projection 21 of the cover plate 5 and the manhole frame 2 are provided. The circumferential position of the cover plate 5 is defined by the V-shaped mutual fitting with the receiving projection 22. The through-hole 22b provided in the receiving protrusion 22 prevents sediment from accumulating in the V-shaped groove 22a. When the lid plate 5 is lifted by the increase of the internal pressure of the manhole and the pendulum hook 14 is locked by the locking portion 19 or when the fixed hook 8 is locked by the flange 7 on the inner periphery of the manhole frame 2 Further, if the dimensional relationship is such that the V-shaped tip of the positioning projection 21 does not come off from the V-shaped groove 22a of the receiving projection 22, the positional displacement of the lid plate 5 when the lid plate 5 is fitted to the manhole frame 2 again is prevented. it can.
[0013]
A guide bar 10 suspended from the tangential fulcrum shaft 9 at a position opposite to the pendulum hook 14 loosely connects the cover plate 5 to the manhole frame 2. Insert the tip of the bar 20 into the lever insertion hole 18 to remove the pendulum hook 14, and with the pin 20 a at the tip of the bar 20 hooked under the cover plate 5, the base end (hand side) of the bar 20 is lowered. The lid plate 5 and the manhole frame 2 are disengaged from each other by pushing down and lever action. If the lever insertion hole 18 is formed longer in the radial direction of the cover plate 5 and the upper surface of the cover plate 5 at the outer peripheral end is formed lower than the upper surface of the manhole frame 2, the bar 20 inserted into the lever insertion hole 18 is formed. When tilted toward the outside of the cover plate 5, the burl 20 comes into contact with the inner peripheral edge of the upper surface of the manhole frame 2, and the cover plate 5 is lifted by the lever action of the burl 20 using that portion as a fulcrum (see FIG. 6).
[0014]
When the fitting between the cover plate 5 and the manhole frame 2 is disengaged, the cover plate 5 is lifted obliquely upward by the bar 20, and the cover plate 5 is dragged and moved laterally so that the tip 8 a of the fixing hook 8 is the flange of the manhole frame 2. 7 (see FIG. 7). The lid plate 5 from which the pendulum-type hook 14 and the fixed hook 8 are disengaged is turned to the opposite side by rotating around the tangential fulcrum shaft 9 that suspends the guide bar 10 or rotating around the guide bar 10. Either turn it upside down or pull the burl 20 laterally, rotate it around the guide bar 10 and shift it to the side of the manhole hole (see FIGS. 8 and 9). When closing the opened cover plate 5, the cover plate 5 may be covered on the manhole frame 2 in the reverse operation.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
1 to 9 show an embodiment of the present invention. The manhole in the illustrated embodiment includes an outer frame 1 and an inner frame 2 to which the manhole frame of the present invention is applied. The inner frame 2 can move up and down and slightly move within the outer frame 1. By adjusting the relative position of the outer frame 1 with the screw device 3, the upper surface of the inner frame 2, that is, the upper surface of the manhole frame, can be adjusted according to the height and gradient of the ground surface.
[0016]
The inner periphery of the upper end of the inner frame 2 is a conical inner peripheral surface 4, and the outer periphery of the cover plate 5 is a conical outer peripheral surface 6 having the same angle. The cover plate 5 is fitted in a state in which the upper surface 2a of the inner frame 2 and the upper surface of the cover plate 5 are flush with each other in a state where the cover plate 5 is fitted into the inner peripheral surface 4 of the cone. A circumferential flange 7 is formed at a position slightly below the inner circumferential surface 4 of the inner frame 2 and is inserted at one position on the lower surface of the outer peripheral side of the cover plate 5 with a gap below the flange 7. A fixed hook 8 having a tip 8 a is formed integrally with the lid plate 5.
[0017]
A guide bar 10 is suspended by a tangential fulcrum shaft 9 near the fixed hook 8. The guide bar 10 is suspended at the tip of the bent portion outside the upper end, and the guide bar 10 itself is suspended in a state of being slightly inclined toward the outside. The guide bar 10 has a circular cross section and is gently bent into an arcuate shape, and a substantially middle portion thereof is loosely inserted into a long hole 11 of a guide bracket provided on the inner periphery of the inner frame 2 (see FIG. 1).
[0018]
An outer fulcrum bracket 12 and an inner fulcrum bracket 13 protrude from the outer peripheral lower surface of the cover plate 5 at a position facing the guide bar 10 in the diameter direction, and the outer fulcrum bracket 12 opens toward the inner peripheral side. A pin hole 12a is formed, and the inner fulcrum bracket 13 is provided with a pin groove 13a that extends in the horizontal direction, has one end open, and opens outward. The pin groove 13a is U-shaped in cross section, and the back end is a semi-circular end surface. The pendulum hook 14 is suspended by a pin hole 12a and a pin groove 13a.
[0019]
The pendulum hook 14 has a key 14a at the lower end and a closing plate 14b and pin projections 14c and 14d at the upper end. One pin protrusion 14c is inserted into the pin hole 12a of the outer fulcrum bracket 12, and the other pin protrusion 14d is inserted from the open end to the deep end of the pin groove 13a. A bolt insertion hole 13b in the radial direction of the cover plate 5 is provided at a predetermined position of the pin groove 13a. By inserting the bolt 15 into the bolt insertion hole 13b and fastening with the nut 16, the inside of the pin groove 13a is provided. The position of the pin protrusion 14d is defined. In this state, the pendulum type hook 14 is suspended around the fulcrum shaft 17 in the radial direction of the cover plate 5 by the pin projections 14c and 14d pivotally attached to the pin hole 12a and the pin groove 13a.
[0020]
The closing plate 14b extends in the same direction as the key 14a at the tip of the pendulum hook 14. A lever insertion hole 18 penetrating the lid plate 5 is formed in the upper portion of the closure plate 14b in a shape elongated in the radial direction of the lid plate 5. Is provided. The thickness of the cover plate 5 at the portion following the outer peripheral side end of the lever insertion hole 18 is substantially the thickness of the lower half with the upper half removed. On the inner periphery of the inner frame 2, a rod-shaped locking portion 19 that protrudes toward the inner periphery is integrally formed at a position corresponding to the lower side of the lever insertion hole 18. When the pendulum hook 14 is naturally suspended, the closing plate 14b comes into contact with the lower surface of the lever insertion hole 18 to seal the lever insertion hole 18, and in this state, the key 14a at the tip of the pendulum hook 14 is engaged with the locking portion 19. (See FIG. 4).
[0021]
When the tip of the bar 20 is inserted into the lever insertion hole 18, the closing plate 14 b is pushed down, and the key 14 a of the pendulum-type hook 14 integrated therewith is withdrawn from below the locking portion 19. When the bar 20 is tilted outward, the bar 20 comes into contact with the inner peripheral edge of the upper surface of the inner frame 2 because the thickness of the cover plate 5 at the outer peripheral portion of the lever insertion hole 18 is cut off in the upper half. It becomes a lever fulcrum when the cover plate 5 is disengaged (see FIGS. 5 and 6).
[0022]
A positioning protrusion 21 having a V-shaped cross section having a downward ridge line in the radial direction of the cover plate 5 is integrally provided at an arbitrary position on the lower surface of the outer peripheral portion of the cover plate 5. A receiving projection 22 having a V-shaped groove 22a in the radial direction of the cover plate 5 is integrally formed on the inner peripheral surface of the inner frame 2 corresponding to the positioning projection 21. The receiving protrusion 22 is provided with a through-hole 22b continuous with the bottom surface of the V-shaped groove 22a, so that the earth and sand do not collect in the V-shaped groove 22a by dropping through the through-hole 22b. . When the cover plate 5 is attached to the inner frame 2, the V-shapes of the positioning projection 21 and the receiving projection 22 are fitted together to position the cover plate 5 in the circumferential direction.
[0023]
The cover plate 5 is lifted, for example, by an increase in the internal pressure of the manhole, and the key 14a of the pendulum hook 14 is brought into contact with the locking portion 19, or the tip of the fixed hook 8 is brought into contact with the flange 7, so that the lifting height is increased. When the height is restricted, the V-shapes of the positioning projection 21 and the receiving projection 22 maintain the positional relationship of interfering with each other. Therefore, when the cover plate 5 is again attached to the manhole frame 2, it is shown in FIG. The positioning state is restored.
[0024]
Note that the V-shaped relationship between the positioning protrusion 21 and the receiving protrusion 22 can be a reverse relationship, that is, a reverse V-shaped relationship, that is, a reverse V-shaped fitting relationship.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of a manhole cover plate. FIG. 2 is a cross-sectional view of a cover plate positioning projection as viewed from the inside. FIG. 3 is a detailed plan view of a pendulum type hook portion. Cross-sectional side view of hook part [FIG. 5] Side view showing the state of the pendulum-type hook when the bar is inserted [FIG. 6] Explanatory view of opening the cover plate with the bar [FIG. 7] Description of lifting the cover plate upward with the bar [Fig. 8] Cross-sectional view of the lid plate rotated 180 degrees around the guide bar [Fig. 9] Cross-sectional view of the lid plate rotated 180 degrees around the tangential fulcrum axis of the guide bar [Description of symbols]
2 Inner frame (manhole frame)
2a Upper surface 4 Conical inner peripheral surface 5 Cover plate 6 Conical outer peripheral surface 7 鍔 8 Fixed hook 9 Tangential fulcrum shaft
10 Guide bar
11 Guide bracket slot
14 Pendulum hook
14a key
14b Blocking plate
17 fulcrum shaft
18 Lever insertion hole
19 Locking part
21 Positioning protrusion
22 Receiving protrusion
22a V-shaped groove
22b penetration

Claims (2)

The conical inner peripheral surface (4) formed on the inner periphery of the upper end of the manhole frame (2) and the conical outer peripheral surface (6) of the cover plate (5) are fitted together so that the cover plate (5) is attached to the manhole frame (2). The cover plate (5) is attached to a lever insertion hole (18) provided at one location near the outer periphery of the lid plate (5) and suspended below the lever insertion hole (18) so as to be swingable around the fulcrum shaft (17). and suspended the pendulum-type hook (14), extending substantially horizontally closed from the pendulum-type hook (14) and its pivot axis together (17) portions the same direction pendulum type hook (14) the tip of the key (14a) And a fixed locking part (19) to which the key (14a) is locked on the inner periphery of the manhole frame (2), and the pendulum hook (14) is naturally suspended. In the locked structure of the manhole cover plate in which the key (14a) is inserted below the locking portion (19) and the closing plate (14b) closes the lever insertion hole (18).
The fulcrum shaft (17) of the pendulum hook (14) is provided in the radial direction of the cover plate (5) , and the locking portion (19) is provided to protrude radially on the inner periphery of the manhole frame (2) . the inner peripheral surface of the cover plate the outer peripheral lower surface one place and this opposing manhole frame (5) (2), the cover plate (5) radially positioning projections of V-shaped cross-section having a ridge (21) of Toko of A manhole cover plate characterized in that a positioning pair comprising a V-shaped groove (22a) fitted with a V-shape of a positioning projection (21) and a receiving projection (22) is integrally formed . Locking structure. Manhole frame (2) Conical inner peripheral surface formed on the inner periphery of the upper end of (Four) And lid plate (Five) Conical outer surface of (6) And fit the lid plate (Five) Manhole frame (2) Attached to the lid plate (Five) Is a lever insertion hole provided at one location near the outer periphery (18) And this lever insertion hole (18) The fulcrum shaft at the lower part of (17) Pendulum hook suspended around swinging freely (14) And this pendulum shaped hook (14) And its fulcrum shaft (17) Pendulum hook from part (14) Tip key (14a) Obstruction plate extending approximately horizontally in the same direction as (14b) With a manhole frame  (2) The key to the inner circumference (14a) Fixed locking part to be locked (19) Pendulum hook with (14) In a state where it is suspended naturally (14a) Locking part (19) Inserted under the obstruction plate (14b) Lever insertion hole (18) In the locking structure of the manhole cover plate that closes
Pendulum hook (14) Fulcrum shaft (17) Is the lid plate (Five) The locking part is provided in the radial direction of (19) Manhole frame (2) It is provided to project radially in the inner circumference of
Pendulum hook (14) Cover plate facing the mounting position of the diametrically (Five) Tangential fulcrum shaft on the outer peripheral lower surface (9) Guide bar bent around in a bow shape and formed with an inverted T-shaped locking end at the tip (Ten) This guide bar is suspended (Ten) Is a manhole frame (2) Long slot in the radial direction provided on the side (11) And this guide bar  (Ten) Close to manhole frame (2) Fixed collar formed on the inner peripheral surface of (7) And this fixed fence (7) With a tip inserted from the inside in the radial direction with a sufficient gap below (Five) Fixed hook integrated with (8) And a locking structure for a manhole cover plate.

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