JPS61207727A - Opening and closing device for manhole cover with pull-off lever - Google Patents

Abstract

PURPOSE:To relieve a labor, by a method wherein a hook is rotatably located to the lower part of a support bracket situated to the lower part of a body, and a fulcrum part is positioned between the actuating point side and the point of force side of the body so that a set position is regulatable. CONSTITUTION:After a support bracket 15 is brought near to the hook 3 side to set a lever ratio to a high value, the hook 3 is inserted into a hatch 31d of a manhole cover 30, and a locking groove is engaged with the hatch 31d. The point of force 2a side of a body 2 is depressed downward to lift up the cover 30. The bracket 15 is moved to the portion, most closer to the point of force 2a, of a fulcrum regulating part 2C to set a lever ratio to a low value. The point of force 2a is further depressed to push up the one end of the cover 30, and after a roller is inserted under the cover 30,the cover 30 is pulled out by pulling the point of force 2a side.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to a manhole cover opening/closing device for inspecting the operation of underground pipes or telephone A power wiring, etc. The present invention relates to a manhole cover opening/closing device for inspecting the operation of underground pipes or telephone A power wiring, etc. Regarding the opening/closing device specified for use with double-hole type manhole covers, so-called hatch type, in which a pull-up handle made of a round rod molded in a cylindrical shape is attached to a hollow hole (inside the cover) so that it can be pulled up freely, it is firmly attached to the manhole holder frame. This relates to a device that can perform both the work of stripping off a manhole cover that is stuck to the manhole cover and the subsequent work of moving it.

(Background of the Invention) The manhole cover that is the subject of treatment of the present invention has an extremely wide variety of types of hook holes formed for opening and closing.1
In addition to its heavy weight, sand and mud are always stuck between the manhole cover and the manhole receiving frame, and ``edge cutting'' work is required to release this stuck state before opening and closing the ivy. Opening it was extremely difficult.

First, regarding the two holes of the manhole cover, there are various structures as shown in FIG. Of course, this explanatory diagram in FIG.
(If both holes of an individual shape are not specifically designated, both holes 31 are indicated).1 Naturally, one or two of these holes 31 can be selectively used as one. It is formed on the manhole cover.

To further explain these, the holes 31a and 31b in FIG. 10 are of the British standard, and are for inserting the locking protrusion 41 of the hanging hook 40 shown on the diameter line of the circular hole. Insertion holes are formed for insertion of the holes, and the directions of each hole are 90 degrees different from each other. Further, 31c is made by hollowing out the surface of the lid and fixing a round bar to the center of the hollow so that it does not protrude. Reference numeral 31d is a so-called hatch-type drawer handle in which a U-shaped drawer handle 31d (hereinafter referred to as a hatch) is attached to one hollow hole so that it can be pulled up from the lid. These two holes 31c and 31d are sufficient as long as a hanging hook can be hung on these hanging portions. It is something that performs work. In this way, the symbols 31a to 31d
The two holes shown in 1 allow the manhole cover to be pulled up easily, but the two holes indicated by 1 symbols 31e and 31f are so-called pick holes, and are often used in water, sewage, and telephone facilities in the United States. It is a square hole (a circular hole).

There are generally the types of both holes 31 of the manhole cover 30 as described above, but the present inventor first developed a pick hole type of both holes 31e.
, 31f and British Standard Hook Hole 31a, 131b), and then proposed a switchgear compatible with both holes 31c of the fixed hanging rod type.1 In the above proposal, Also, the hatch type piece hole 31d could not be accommodated.

Regarding the issue of weight, 1) This type of manhole cover opening/closing device is a so-called portable tool, so its total length is limited to about 1 meter at most). It was extremely difficult to do. That is, as shown in Figure 11, cutting the edge of this type of manhole cover requires a load of approximately 1,000 kg or more.Moreover, the manhole cover currently in use has its hook hole located 80 to 90 degrees from the outer periphery.
Many of them are set to about 0 mm, and some even reach 150 mm.

Under these conditions, for example, the force point load between the worker and the person is 6
If it is 0kg, is it Tameshi? , is 10 when working under the above-mentioned 1m constraint with a lever located midway between the point of application and the point of force.
To lift 00 kg, the lever ratio is required to be approximately 17 times. For this reason, the distance between the point of action and the fulcrum must be set in the range of 50 to 60 mm.Since the position of the hook hole is 80 to 90 mm from the circumference of the manhole cover, it is impossible to set it in such a situation. 1 It was almost impossible.

Moreover, in order to remove and move the manhole cover (after cutting the edges of the manhole cover), a lift height of about 100 mm is required at least because a roller, etc. is inserted below it, but the greater the lever ratio, the less the lift amount. It was impossible to move the manhole cover after cutting the edges. For this reason, conventionally, when opening and closing this type of manhole cover, the tool for cutting the stuck edge is either a separate special tool or struck with a hammer, and the manhole cover after the edge cutting is removed separately. This had to be carried out using a tool that was transported using an IJ raft.

(Prior art) By the way, prior art related to this type of manhole cover opening/closing device includes, for example, Japanese Patent Publication No. 52-46025 ``Manhole Opener'', Kyushu Publication No. 55-88452, ``Manhole Cover Opening Device'' -173227 "Hook for manhole cover" etc. exist. However, its use is limited to the above-mentioned so-called British standard manhole cover with six hooks, and cannot be applied to the manhole cover with the hatch-shaped hook hole type shown by reference numeral 31d in Fig. 10. there were.

Furthermore, in all of these methods, the main focus is generally on the movement of the manhole cover, and it is virtually impossible to trim the edges of a manhole cover that is stuck.

This is because the position of the above-mentioned hook hole 31 is closely related, and in the case of a manhole cover having a hatch type hole type which is particularly intended by the present invention, the position of the hook hole 31 is from the outer periphery of the manhole cover 30. Since most of the hooks have a length of 100 mm or more, in the prior art, for example, the above-mentioned hanging hook 4
In the technique of setting the point of action of the lever on the vertical line of the hook hole using 5, the distance of one fulcrum becomes long and it is not possible to obtain the high leverage ratio required for fixed edge cutting work.
It has been impossible to carry out the stuck edge cutting operation efficiently.

As mentioned above, for this type of equipment that requires a high leverage ratio, the ultimate technology to shorten the fulcrum distance by just 10 mm is to improve the leverage ratio several times, so it is necessary to cut the fixed edges. It seems that everyone understands that this is an extremely important requirement for ensuring work safety.

(Objectives) First, the present invention provides a manhole cover opening/closing device that can perform both the moving operation of a manhole cover having a hatch-type hook hole, which has been difficult to perform fixed edge cutting operations, as well as the preceding edge cutting operation. This is the first objective.

Furthermore, in addition to the above-mentioned object, the present invention enables not only the opening/closing operation by pulling up the manhole cover, but also the rotational operation of lifting or pushing down the manhole cover itself using, for example, a roller inserted below the manhole cover as a rotation fulcrum. It is intended for other purposes.

"Structure of the Invention" (Means for Achieving the Object) That is, the manhole cover opening/closing device of the present invention comprises: (1) a lever-like main body; and (1) a fulcrum portion provided between an application point side and a power point side of the main body. 1. The hanging hook is provided with an insertion portion to be inserted into the hatch 31d of the manhole cover, and 1. The hanging hook is provided with a protruding locking protrusion on the upper portion thereof to form a locking groove.
The fulcrum for rotation with the main body is provided at a position eccentric to the locking groove, and the fulcrum portion can be freely set at at least two points in the longitudinal direction of the main body. It is something.

(Example) The present invention will be specifically described below based on the illustrated example. Reference numeral 1 denotes a manhole cover opening/closing device according to the present invention, which is constructed of a lever rod-shaped main body 2 and a fulcrum portion 4 for a hanging hook 3 as main members.

First, the main body 2 is shaped like a lever bar bent in an inverted shape, for example, and is composed of, for example, pipes of different diameters with a hexagonal outer cross section and a circular hole in the center. It is. Of course, the reason for using a steel rod with such a hexagonal cross section is to take into consideration the convenience of mounting the fulcrum portion 4, etc., as will be described later, and the cross-sectional shape is not necessarily limited to this. There is no problem in using other square pipes, round pipes, etc. In short, it is sufficient that it is made of a material that has enough strength to withstand the opening and closing operations of the manhole cover 30.

One end of this main body 2 serves as a force point 2a, and a handle 2b is attached thereto, and the range on the tip side from the bending point at the other end is used as a fulcrum adjustment portion 2C. The end of the main body 2 on the side of the fulcrum adjustment section 2C serves as a point of action, and a support bracket 5 for the hanging hook 3 is provided at the tip.

This device is composed of, for example, a hexagonal fixing portion 6 that is fitted onto the outside of the main body 2, and bifurcated leg portions 7 extending downward in parallel from the hexagonal fixing portion 6.1 A pair of left and right leg portions 7
A hanging hook 3 is rotatably attached to the lower end of the hanger via a pin-shaped rotary support point 8.

This hanging hook 3 is wedge-shaped, and includes an insertion part 9 for attaching one end to the rotation support point 8, and a locking protrusion 10 provided on the upper side of the free end side of the insertion part 9 to form a locking groove. 11. Of course, one end of the insertion part 9 attached to the rotation support point S constitutes a rotation part 13 having a rotation hole 12. The number of locking protrusions 10 and locking grooves 11 may be one each, but two of each are shown to facilitate operation when the hatch cannot be lifted to a specified size due to rust on the hatch or the like. This is taken into consideration, and a preferable configuration is 2 to 3 of each. Of course, the specific configuration of this hanging hook 3 may be of any other suitable shape, but the key point is that the rotation hole 12 is located eccentrically with respect to the vertical direction of the locking groove 10 of the insertion portion 9. It suffices if it is configured so that it can be installed in

As can be understood from the above explanation, the hanging hook 3 can be rotated below the support bracket 5.1 Furthermore, the insertion portion 9 of the hanging hook 3 is positioned upward (on the side of the fixed portion 6 of the support bracket 5). It is constructed so that it can be rotated forward to an angle within a range of 120 degrees from a position where it can be sufficiently overlapped between the legs as shown in Figure 4 when rotated. It is. In this embodiment, the hanging hook 3 is connected to the main body 2 via the support bracket 5, for example.
The support bracket 5 and the main body 2 are fixed to each other by a combination of bolts and nuts 14 at the fixing portion 6 of the support bracket 5.
Although the structure is such that the support bracket 5 can be freely removed from the main body 2 by removing the nut 14, there is no problem with the relationship between the support bracket 5 and the main body 2 even if they are fixed by welding or the like. .

Next, the fulcrum part 4 will be described.1 This part is composed of a fulcrum bracket 15 and a wheel 16 at its lower end, as in the hanging hook 3. First, this fulcrum bracket 15 has a hexagonal cross-section fixed part 171 to the main body 2, and a leg part 1 extending below the fixed part 171.
8 and an axle 19 projecting horizontally from its legs 18) Further, a female thread 20 is formed in a part of the fixing part 17, and a lock bolt 21 is screwed therein) A fulcrum bracket 15
The main body 2 is fixed to the main body 2.

Incidentally, the fixed part 17 and the main body 2 in the fulcrum bracket 15
The two are slidably fitted into each other, but because of their hexagonal cross-section, there is no risk of them rotating and they can always remain upright. Of course, if the main body 2 has a round bar-like cross section, other appropriate rotation prevention means such as a keyway-like fit may be provided as necessary. The axle 1 in such a fulcrum bracket 15
A wheel 16 is attached to 9, and 1 this wheel 16
For example, the snap pin 22 is fitted onto the end of the axle 19.

Of course, in this embodiment, the wheels 16 are constructed with a pair of left and right wheels, but if relatively wide roller-shaped wheels or the like are used, only one wheel may be provided for each shaft.

In addition, as will be described later, such wheels are preferable in that they allow smooth operation of moving the device or opening and closing the manhole cover 30, but they are not necessarily limited to rotating wheels, and are therefore simply used. It may be protruding. In addition, the present invention requires that the setting position of this fulcrum part number be freely adjustable, but the specific configuration for making it freely adjustable can be found in the embodiments already described. It is not limited.

For example, as shown in FIG. 9-A, the fulcrum bracket 15 is rotatably installed on the main body 2, so that by rotating this bracket, the setting position of the wheel 16 can be adjusted to the point of force 2a, or to the hanging hook which is the point of action. It may be set closer to 3. In addition, it is sufficient that the fulcrum itself can be selected from at least two locations depending on when cutting the edges and when moving the manhole cover.
As shown in Figure 1, two fulcrums 15a,
Since the fulcrum 15b is provided in the main body 2, there is no problem even if it is used on the fulcrum side when it is not in use by moving it aside or upward. The point is that the fulcrum positions defined by the lower end of the fulcrum part number can be selectively set in at least two positions with respect to the main body.

Further, there are other embodiments of the hanging hook 3 as shown in FIG. That is, as will be described later, the hanging hook t is designed in consideration of the convenience of use, and improves the insertion of the insertion portion, the positioning of the locking groove, and the rotatability.

A locking groove 11' is formed by providing locking protrusions 10' at intervals matching the thickness of the notch 31d on the upper side of the conical insertion portion 9'. Support bracket 5
A rotating portion 13' is formed at the lower end thereof with a rotating hole 12 for rotatably fixing the shaft. The locking protrusion 11' and the rotation hole 12 are located on a line, and the rotation hole 12, which is pivoted to the support bracket 5, is an insertion portion where the locking protrusion 11' overlaps with the front end of the support bracket 5. The upper surface of the support bracket 9' is provided so as to come into contact with the front end portion of the support bracket 5, and the support bracket 9' is integrally molded into an L-shape as a whole.

The present invention has the specific configuration as described above, and therefore operates as described below to open and close the manhole cover 30. Manhole cover 30 in closed state below
This is a step-by-step explanation of the work involved in opening the door.

Edge cutting work First, when cutting edges, remove the fixed mantle lid 30.
It is used to slightly levitate the object, and requires a force of approximately 1,000 kg. In this case, first the fulcrum bracket 15
Loosen the lock bolt 21 at the fulcrum bracket 15.
is sufficiently pulled toward the hanging hook 3 side, and the lever ratio is set to be large. After that, the insertion part 9 of the hanging hook 3 is inserted into the hatch 31d of the manhole cover 30 (see FIG. 5-A).The procedure for inserting the hanging hook 3 into the raised hatch 31d will be explained below. Hold the hanging hook 3 at a position of approximately 45 degrees forward from the overlapping position on the leg portion 7 of the support bracket 5 described above, and move the hatch 3 in a state in which the main body 2 is tilted approximately 45 degrees to the left or right.
1d, the position of the locking groove 11 can be matched with the position of the hatch 31d without the locking protrusion 10 colliding with the hatch. Subsequently, the support bracket 5 of the main body 2 is raised and returned to the vertical state. At this time, the wheel 16 is not yet in contact with the ground, so there is nothing that will impede the rotation of the hook 3 in the hatch 31d.The hook 3 rotates 45 degrees and the locking groove 11 locks on the bottom surface of the hatch 31d. The locking protrusion 10 prevents the hook 3 from coming off the hatch 31d during subsequent operations.

Another embodiment of the above-mentioned hanging hook is designed in consideration of the convenience in aligning the position of the locking groove 11' with the position of the hatch 31d, and has an insertion part 9'' having a conical shape with one tip tapered.
When inserting into the hatch 31d, use one hanging hook 3' to prevent the locking protrusion 10' from touching the hatch 31d and to prevent the wheel 16 from interfering with insertion. Attach the hanging hook 3' to the hatch 3 in a state in which it is rotated approximately 45 degrees forward from the position superimposed on the support bracket 5.
1d, the insertion part 31d has a conical shape with a tapered end, so it is easy to insert the hatch 31d, and the support bracket of the main body 2 can be returned to the vertical position by pushing it into the thick part of the cone. Since the lower side of the insertion part 9' is circumferential, the rotation of the hanging hook l through 45 degrees is extremely smooth. It is possible to do both at the same time while eliminating the awkwardness.

Two or three locking protrusions 10 are provided so as to form a locking groove 11 that matches the thickness of the hatch 31d. Therefore, the hatch 31 may not meet the standard dimensions due to rust on the hatch 31d.
This is done in consideration of convenience in case d does not increase. Further, the state of engagement between the hatch 31d and the locking groove 11 is such that the hatch 31d does not need to be pulled out from the locking protrusion 10, and does not necessarily have to be in a strong engagement state.

After engaging the locking groove 11 with the hatch 31d as described above, one operator operates the main body 2 so as to push down the force point 2a side. When operated in this manner, the main body 2 moves using the lower end island of the fulcrum portion 4, that is, the ground contact portion of the wheel 16 as a fulcrum, so that the hanging hook 3 side, which is the active end, is pulled up.

In this case, the rotational support point 8 at the lower end of the counterfeit support bracket lifts the hanging hook 3-1)E
, At this time, the locking groove 1 of the insertion part 9 inserted into the hatch 31d
Since 1 and this rotation support point 8 are in an eccentric state, as 1 is pulled up, the insertion portion 9 is moved as shown in FIG. 5-B.
The lower surface of the tip (the surface on which the locking protrusion 10 is not formed)
is pressed against the top of the manhole cover, and the 1 locking groove 1
1 is interlocked with each other to securely engage the hatch 31d of the manhole cover 30.

In this state, when the force point 2a side of the main body 2 is further pushed down, the hatch 31d and the hanging hook are This actuates to pull up the periphery of the manhole cover 30 while further strengthening the locked state with the manhole cover 3, thereby releasing the fixation of the manhole cover 30 and performing a so-called edge cutting.

Even if the hatch 31d is formed at an inner position away from the periphery of the manhole cover 30, the distance between the point of action and the fulcrum when cutting the fixed edge is 1. The rotation support point 8, which is the action end, is inserted into the hanging hook 3. Depending on how the length of the part 9 is set, it can be set sufficiently close to the periphery of the manhole cover 300, or even on the manhole receiving frame, and the fulcrum part 4 can be biased sufficiently toward the working end. For example, 50
It is also possible to make it within mm. This sufficiently increases the leverage ratio, strengthens the engagement between the hanging hook 3 and the manhole cover 30, and makes it possible to exert a strong edge-cutting force.

2) Pulling up the manhole cover Next, the operation of pulling up the manhole cover 1 and inserting a roller 50 for moving the manhole cover on its underside will be explained. Since this work involves pulling up one side of the manhole cover 30, which has already been edge-trimmed, a load of approximately 1/2 of its own weight is applied, and therefore the lever ratio of the main body 2 is It is not required to be very large, but instead requires a sufficient lift height on the side of the point of action.

This operator loosens the lock bolt 21 on the fulcrum bracket 15, moves the fulcrum bracket 15 to the most forceful point 2a'JF of the fulcrum adjustment part 2C on the main body 2, and sets the lever ratio to be smaller. Hutch 31d
(Figure 6-a).

Thereafter, by pressing down the force point 2a side of the main body 2 in the same way as the edge cutting work described above, the hanging hook 3 raises one end of the manhole cover 30 sufficiently high as shown in FIG. After operating in this way, immediately insert the roller 50 under the manhole cover 30, hold the power point side of the main body 2 or the handle 2b, and push the manhole cover 30 into the roller 5.
Pull it out so that it is placed on 0. If there is a problem due to a protrusion on the bottom of the manhole cover, perform the following pull-out operation.

3) Pulling out the manhole cover using the reversing operation method a) Pushing down operation (Fig. 7-A) This operation is performed after inserting the roller 50 into the lower surface of the manhole on the side that was pulled up in the previous process, so another roller is inserted. This is a handling operation for inserting into the lower surface of the manhole cover 30 on the side that has not been pulled up yet, and is an effective operation when there is a locking protrusion or the like on the lower surface of the manhole cover. To lift the other side using the roller 50 inserted into the lower surface of the side that was pulled up in the previous process as a fulcrum:
As shown in FIG.
It is inserted into the hatch 31d at 0.

Incidentally, since the fulcrum part 4 of the present device is not particularly used in this operation, there is no problem in setting the fulcrum part 4 in either position. After that, it is operated so as to pull the point of force on the main body 2 clockwise in the figure. . As a result of this operation, the hatch 31d which is sandwiched between the support bracket 5 and the insertion section 9 is moved to the rotation support point 8 at the lower end of the support bracket 5, with the tip of the insertion section 9 serving as a fulcrum.
In the figure, it acts to almost pull upwards.

In such a case, the hanging hook 3, which is rotatably attached here, is held on the manhole cover 30 more strongly by lifting the rotation support point 8 side of the first insertion portion 9.

When the main body 2 continues to be pulled down in this way, it acts to push down the edge of the manhole cover 30, and the other end of the manhole cover 30 is lifted around the roller 50 inserted below. It is caused by. After that, one or an appropriate number of rollers 50 are inserted into the pulled-up side where no roller 50 has been inserted, and the manhole cover 30 is pulled out from the installed position.

b) Lifting operation (Fig. 7)
The operation is to push down the 1d side, but if you wish to pull up the notch 31d side, press the hatch 3 as shown in Figure 7.
This is done by setting the insertion direction of this device in the opposite direction to 1d. That is, the insertion portion 9 of the hanging hook 3 is inserted into the hatch 31d such that the main body 2 is located on the side of the roller 50 inserted into the lower surface of the hatch 31d.

However, when levering, similarly pull down the force point 2a side of the main body 2.
First, a strong connection between the manhole cover 30 and the manhole cover 30 is established. Next, when the main body 2 is pulled down, the manhole cover 3
For 0, the hatch 3 is centered around the roller 50 as a whole.
A force is applied to pull up the hatch 31d side of the manhole cover 30, which causes the hatch 31d side of the manhole cover 30 to be pulled up.

When operating the roller 50, in addition to the operation method described in the first section, for example, if the hatches 31d are installed at two opposite locations on the outer periphery of the manhole cover 30 on the diameter line, 1.
After first inserting the roller 50 near the hatch 31d on the lifted side, it is also possible to pull up the other hatch 31d using the method described in section (2) above and insert another roller 50. It is something.

4) Closing operation When opening a manhole cover in this manner, at least one roller is usually placed near the manhole hole with at least one roller remaining on the underside of the manhole cover 30 until the operation is completed. After that, to return it, for example, use the so-called reversal operation method as shown in FIG. This should be pulled into the receiving frame.

Of course, this return direction may be operated in the opposite direction as shown in FIG. 7 without any problem. The point is that the manhole cover 30 should be moved using rollers so that at least one side of the manhole cover 30 fits into the manhole receiving frame. After that, the manhole cover 30 is pulled up using the normal lifting method shown in FIG. 6, and the roller 50 provided on the lower surface is removed. It is intended to be fitted.

``Effects of the Invention'' As described above, the present invention allows a heavy and strongly fixed manhole cover to be edged and removed with extremely little force, reducing the labor of the worker and providing safe work. Therefore, there will be no more industrial accidents or avoidance by workers of this type of heavy labor, which previously occurred.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the manhole cover opening/closing device of the present invention. Fig. 2 is a side view of the same as above. Fig. 3 is an enlarged exploded perspective view showing the tip side of the device. Fig. 4 is a part of the hanging hook. Fig. 5 is a side view showing the state of use in edge cutting work. Fig. 6 is a side view showing the operation of pulling up a manhole cover. Fig. 7 is a side view showing the reversing operation method, which is another method of using this device. Figure 9 is a perspective view showing another embodiment of the hanging hook. Figure 9 is a skeletal side view showing another embodiment of the fulcrum part. Figure 10 is a perspective view showing another embodiment of the hanging hook. An explanatory diagram showing the hanging hooks shown on the manhole cover and adapted to each hook hole. Figure 11 is a diagram of the action of the lever when opening the manhole cover.

Claims (4)

[Claims] (1) A lever-shaped main body, a hanging hook that rotates along the longitudinal direction of the main body at a rotation support point on the application point side of the main body, and a fulcrum section provided between the application point side and the effort side of the main body. The hanging hook is provided with an insertion part that is inserted horizontally into the drawer handle of the manhole cover, and has a locking groove in the upper part thereof, and the rotation hole with the main body is located at the position of the locking groove. is provided at one end of the insertion portion eccentrically located, and the fulcrum portion further includes:
A manhole cover opening/closing device with a drawer handle, characterized in that the setting position can be freely set at at least two points in the longitudinal direction of the main body. (2) The above-mentioned hanging hook has an L-shaped insertion part that is bent at approximately 90 degrees at the bottom of the rotation part with a rotation hole provided at the top, and is integrally formed, and the insertion part has a tapered tip. It is molded in a conical shape, and has at least one locking groove in its upper part that matches the thickness of the drawer handle of the manhole cover, and the lower part of the support bracket that extends downward from the tip of the main body is provided with the hanging groove. The rotation hole of the hook is rotatably fixed, and the upper part of the insertion part is configured to rotate forward within a range of 140 degrees from a position where it overlaps with the support bracket. An opening/closing device for a manhole cover with a drawer handle according to claim 1. (3) The fulcrum section is comprised of a fulcrum/point bracket that is slidably attached to the main body and extends downward, and a wheel at the lower end of the fulcrum bracket. The opening/closing device for a manhole cover with a drawer handle as described in Items 1 and 2. (4) The fulcrum part is configured by a fulcrum bracket that is slidably attached to the main body and extends downward, and a bearing at the lower end of the fulcrum bracket. The opening/closing device for a manhole cover with a drawer handle as described in Items 1 and 2 and 3.