JPH0637053Y2 - Manhole guard fence - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a protective fence for a manhole that protects a pedestrian from falling when the manhole cover is opened and working.

<Prior Art> Conventionally, when a manhole cover is opened, a general-purpose fence formed into a flat wall is erected on the road surface around the manhole to prevent pedestrians from falling into the manhole. Had been prevented. In addition, a fence dedicated to manholes, which is made by welding pipe material into a cylindrical shape, has been developed.

<Problems to be solved by the invention> When a manhole is surrounded by a conventional general-purpose fence, only the opening part of the manhole cannot be circled. It interferes with traffic. On the other hand, a fence made by welding pipe material into a cylindrical shape is bulky and difficult to stack on a light van or the like, and it is troublesome to transport it to the work site. Moreover, it cannot be used if the diameter of the manhole is different, which is not practical.

<Means for Solving the Problems> The present invention has been proposed in view of the above, and is a manhole protective fence in which a plurality of fence-shaped fence members are detachably connected in a cylindrical shape. By combining a plurality of upper and lower arc-shaped horizontal members and left and right vertical members to form a nearly shield type, a support portion extending outward is provided in the lower part between both vertical members. , The door member is rotatably provided on the upper portion of the vertical member on one side, and the receiving member having the connection hole is provided on the lower portion, and the receiving member having the connection hole is provided on the vertical member on the other side. Combining the first fence member and the fourth fence member as end fence members formed symmetrically about the left and right, and a plurality of upper and lower arc-shaped horizontal members and left and right vertical members to form a nearly shield type As it forms
An intermediate portion in which a support portion extending outward is provided in a lower portion between both vertical members, and a receiving piece or a connecting portion for rotatably and detachably connecting adjacent fence members is provided on the left and right vertical members. Fence member,
A length adjustable connector provided with an engaging portion corresponding to the connection hole of the receiving piece at the tip, and the first fence member and the fourth fence member, which are the fence members for the end, The door members are arranged so as to be adjacent to each other, and the connecting tool is attached between the receiving pieces of the end fence members to adjust the gap on one side of the end fence members so as to be adjustable. At least one intermediate fence member is arranged in the other side space between the first fence member and the fourth fence member, which are end fence members, and adjacent fence members are rotatably attached and detached. It is possible to connect.

<Operation> Since the present invention has the above-mentioned configuration, each fence member and connecting tool can be disassembled to be small during transportation, and when used, a fence for an intermediate section corresponding to the diameter of the manhole on site is used. By adjusting the number of members and connecting the vertical members of the adjacent fence members with connecting tools and connecting members whose length can be adjusted, a nearly cylindrical protective fence is assembled. Then, with the lower end of each vertical member constituting the fence member inserted in the opening of the manhole, the support part formed between the vertical members is locked to the support step part on which the manhole cover was placed, and the protective fence is formed. It can be installed in a stable state, and an operator can enter and exit the manhole by opening and closing the door member.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

The protective fence A of the embodiment shown in FIGS. 1 to 3 has a diameter of about 75.
It is used for a standard manhole of 0 mm, and has a first fence member 1, a second fence member 2, a third fence member 3, and a fourth fence member 4.
4 fence members are detachably and rotatably connected.

The first fence member 1 constitutes one end fence member, and is located at the left end in the illustrated embodiment. This first fence member 1
Is made by arranging a plurality of horizontal members 5a, 5b, 5c, 5d, which are formed by forming a metal pipe into an arc shape with the same curvature, in a substantially parallel manner, and welding linear vertical members 6a, 6b to both ends of these horizontal members 5a. It is fixed by and is formed into a nearly shield type. Further, a brim-shaped support portion 7 extending outward is provided at an outer portion which is raised by a few dozen cm from the lower end between the vertical members 6a and 6b, and a strip-shaped support plate 7 made of a punch plate, a net or the like is provided above the support portion 7. The fall prevention wall member 8 is fastened to the entire width, and one vertical member
A door member 9a is rotatably and axially mounted above the side surface of 6a, and a receiving piece 11 having a connection hole 10 is provided below the door member 9a so as to connect to the side surface of the other vertical member 6b. A receiving piece 11 having a hole 10 is provided so as to project upward, and also has a height similar to that of the receiving pieces 11 ...

On the other hand, the second fence member 2 which constitutes the middle fence member is a straight line at both ends of a plurality of cross members 12a, 12b, 12c, 12d formed in an arc shape with a predetermined curvature like the first fence member 1. Vertical members 13a, 13b
Is fixed by welding to form a nearly shield type. Also, vertical material
A brim-shaped support portion 14 extending outward is provided at an outer portion above the lower end between 13a and 13b by a predetermined height, and a fall prevention wall member 15 is provided above the support portion 14, and the first fence member 1 is provided. Vertical member located on the side
A first type connecting member 17 having a downward shaft 16 on the side surface of 13a ...
Is provided at a height at which it can be engaged with and disengaged from the receiving piece 11 of the first fence member 1, and the receiving pieces 11 having the connection holes 10 are provided so as to project on the side surface of the other vertical member 13b.

In addition, the third fence member 3 that constitutes the middle fence member includes a plurality of cross members 18a, 18b, 18c, 18d formed in an arc shape with a predetermined curvature.
Linear vertical members 19a and 19b are fixed to both ends of the by welding to form a substantially shield type. Further, a brim-shaped support portion 20 that extends outward from a lower end between the vertical members 19a and 19b to an outer portion above a predetermined height.
Is provided, a fall prevention wall member 15 'is provided above the supporting portion 20, and the connection hole 1 is provided on the side surface of the vertical member 19a located on the second fence member 2 side.
The receiving piece 11 having 0 is projected at the same height as the receiving piece 11 of the second fence member 2, and the receiving piece 11 or the first type connecting member 17 is projected on the side surface of the other vertical member 19b. I will do it.

Furthermore, the fourth fence member 4 constituting the other end fence member,
Is approximately symmetrical to the first fence member 1 described above,
A plurality of horizontal members 21a, 21b, 21c, which are formed in an arc shape with a predetermined curvature,
Linear vertical members 22a and 22b are fixed to both ends of 21d by welding to form a substantially shield shape. Further, a brim-shaped support portion that extends outward from the lower end between the vertical members 22a and 22b to the outer portion above the predetermined height.
23 is provided, a fall prevention wall 24 is provided above the supporting portion 23, and the first type connecting member 17 or the receiving piece 11 is provided so as to be adjacent to the side surface of the vertical member 22a located on the third fence member 3 side. Receiving piece of the third fence member 3
11 or the first type connecting member 17 is configured to be detachable, the door member 9b is rotatably mounted above the side surface of the other vertical member 22b, and the connecting hole 10 is provided below the door member 9b. The receiving piece 11 is provided so as to project.

As described above, between the first fence member 1 and the second fence member 2,
The third fence member 3 and the fourth fence member 4 are connected by a receiving piece 11 having a connection hole 10 and a first type connection member 17 having a shaft 16 that can be fitted into the connection hole 10. Therefore, these fence members 1, 2 ... Can be rotated around the shaft 16 fitted in the connection hole 10, and by removing the shaft 16 from the connection hole 10, each fence member can be easily It can also be released.

Further, the first fence member 1 and the fourth fence member 4 described above, and the second fence member 2 and the third fence member 3 are detachably connected by a connector 25 whose length can be adjusted. Then make a cylindrical shape. The connecting tool 25 shown in the drawing is a so-called turnbuckle, and is formed by screwing male screw rods 28, 28 into female screw holes 27, 27 formed at both ends of an elongated annular buckle 26, respectively. When 26 is rotated, one is a right-hand screw and the other is a left-hand screw.Therefore, the distance between the tip engaging portions 28 'of the male screw rods 28 bent downward increases or decreases depending on the rotating direction of the buckle 26. To do.

Therefore, the engaging portion 28 'of one male screw rod 28 of the connector 25 is fitted into the connecting hole 10 of the receiving piece 11 of the first fence member 1, and the engaging portion 28' of the other male screw rod 28 is connected to the first portion. 4 Connection hole 10 of receiving piece 11 of fence member 4
When the buckle 26 is rotated while being fitted inside, the gap between the first fence member 1 and the fourth fence member 4 can be adjusted as appropriate, and the manhole can be adequately accommodated even if it changes in size a little. be able to. Also, in the same way, one male screw rod
The engaging portion 28 ′ of 28 is in the connection hole 10 of the receiving piece 11 of the second fence member 2, and the engaging portion 28 ′ of the other male screw rod 28 is in the connecting hole 10 of the receiving piece 11 of the third fence member 3. When the buckle 26 is rotated in a state where the buckle 26 is fitted in the above, the gap between the second fence member 2 and the third fence member 3 can be adjusted appropriately. Since the engaging portion 28 'of the male screw rod 28 can be easily disengaged from the connection hole 10 of the receiving piece 1, between the first fence member 1 and the fourth fence member 4, and between the second fence member 2 and the third fence member. Member 3
Can be easily separated.

To set the protective fence A consisting of the above-mentioned structure to the manhole, as shown in Fig. 1, the vertical members 6,1 of the respective fence members 1,2,3,4 are set.
Insert the lower end of 3,19,22 into the opening of the manhole and place the supporting parts 7,14,20,23 of each fence member on the supporting step 29 (step supporting the manhole cover) in the opening of the manhole. Place. Then, the buckle 26 is rotated to adjust the connection length of the connector 25 so that the lower end portion of the vertical member of each fence member presses the inner peripheral surface of the opening of the manhole. In this way, by pressing the lower end portion of each vertical member against the inner peripheral surface of the opening of the manhole, it is possible to prevent the protective fence A from moving in the horizontal direction and to support the supporting portions 7, 14, 20, 23. Securely rests on the support step 29 of the manhole. Therefore, the protective fence A can be installed firmly.

When the protective fence A is installed in this manner, it is possible to prevent a pedestrian from accidentally falling into the manhole even if the manhole cover is removed. In addition, since the fall prevention wall members 8, 15, 15 ', 24 provided on each fence member project upward from the ground surface, even if a small object such as a stone on the road surface rolls, this object will not fall The wall member prevents it from falling into the manhole. Therefore, it is possible to reduce the risk of a falling object from the ground surface hitting an operator working in the manhole.

Then, in order to enter the protective fence A, the worker can remove the lock 30 provided on the door member 9b and open the door members 9a and 9b. In addition, the blower pipe 31, etc.
Since it can be passed between the connecting members 25, 25 for connecting to the fence member, it does not interfere with the entrance and exit of the worker.

Further, when the protective fence A is installed as described above, there is no portion protruding outside the manhole, so that even if a curb on the sidewalk stands near the manhole, the protective fence A and the curb will not interfere with each other. In addition, since the protection fence A can be set up along the opening of the manhole to be surrounded, the area occupied by the protection fence A can be minimized, and the range that hinders the traffic of automobiles and pedestrians can be reduced. Can be reduced more than.

In addition, as shown in FIG. 7, between the second fence member 2 and the third fence member 3 which are the intermediate fence members, the third length whose connection length is fixed is fixed.
The seed connecting member 32 may be detachably connected. The third type connecting member 32 has horizontal pieces fixed to the upper and lower ends of the rod, and shafts 33, 33 project downward from the end portions of the horizontal pieces. By fitting in the connecting hole 10 of the second receiving piece 11 and the connecting hole 10 of the receiving piece 11 of the third fence member 3, the second
The fence member 2 and the third fence member 3 can be detachably connected. The receiving pieces 11 projecting from the second fence member 2 and the third fence member 3 are provided so that their heights are aligned in advance. By using such a third type connecting member 32, the second fence member 2 and the third fence member 3
If it is configured to connect to each other, when it is set as a manhole, it can be firmly installed only by adjusting the lengths of the two connecting tools 25, 25 that connect the first fence member 1 and the fourth fence member 4. You can

Next, a case of installing in a manhole having a small diameter of about 600 mm will be described.

When installing in a small manhole, as shown in FIG. 9, the first fence member 1 and the fourth fence member 4 which are end fence members and the third fence member which is one intermediate fence member. 3 is used, and the connection between the third fence member 3 and the fourth fence member 4 is the same as in the above-described embodiment, but the first fence member 1 and the third fence member 3 are used.
A connecting piece 25, 25 is detachably connected between and.
That is, one end of the male screw rod 28 of the connector 25 is fitted into the connection hole 10 of the receiving piece 11 of the first fence member 1 and the other end of the male screw rod 28 is attached to the receiving piece 11 of the third fence member 3. The fence members 1 and 3 are connected by fitting in the connection hole 10 of. The receiving piece 11 of the first fence member 1 and the receiving piece 11 of the third fence member 3 are attached in advance so that their heights are the same. In order to install each of the fence members 1, 3, 4 described above in the manhole, the lower end of the vertical member of each fence member is inserted into the opening of the manhole in the same manner as in the above-mentioned embodiment to support the supporting portions 7, 20, 23. The buckle 26 of each connector 25 is rotated on the step 29 so that the lower end of each vertical member is pressed against the inner peripheral surface of the opening of the manhole.

In addition, a protective fence A is installed in a large manhole with a diameter of about 900 mm.
11 is installed, in addition to the first fence member 1 to the fourth fence member 4, a fifth fence member 34 as a middle fence member is used as a first fence member 1 and a second fence member 1 as shown in FIG. 2 It is interposed between the fence member 2. The fifth fence member 34 has almost the same structure as the other fence members, and includes a plurality of cross members 35a formed by forming a metal pipe in an arc shape.
35b, 35c, 35d are arranged almost parallel to each other, and the vertical members 36a, 36b are fastened to both ends of these horizontal members by welding to form a nearly shield type, and the vertical members 36a, 36b are formed from the lower end. A flange-shaped support portion 37 extending outward is provided at an outer portion (a position slightly higher than other fence members) raised by a few tens of centimeters, and a belt-like shape made of a punch plate, a net or the like is provided above the support portion 37. The fall prevention wall member 38 of the above is fixed over the entire width, and the downward shaft 1 is attached to the inner side surfaces of both the vertical members 36a and 36b.
A first type connecting member 17 having 6 is provided in a protruding manner. On the outer side surface of the vertical members of the first fence member 1 and the second fence member 2, the fifth fence member is provided.
The receiving portions 39 ... Having a connection hole into which the shaft 16 of the first type connecting member 17 provided in 34 is fitted are previously attached. Therefore, in order to connect one side of the fifth fence member 34 to the first fence member 1, the shaft 16 of the first type connection member 17 of the fifth fence member 34 is connected to the receiving portion 39 of the first fence member 1.
In order to fit inside and to connect to the second fence member 2, the shaft 16 of the first type connecting member 17 of the fifth fence member 34 is connected to the receiving portion of the second fence member 2.
It is enough to fit in each 39.

To install the protective fence A having the above-described configuration in the manhole, the lower end portions of the vertical members of the fence members are inserted into the openings of the manhole, and the supporting portions 7 of the first to fourth fence members 1 to 4 are provided.
14, 20 and 23 are placed on the support step 29 of the manhole, the support 37 of the fifth fence member 34 is placed on the opening edge of the manhole, and the buckle 26 of the connector 25 is rotated to lower the vertical members. Is pressed against the inner peripheral surface of the opening of the manhole.

As described above, the protective fence A according to the present invention can cope with a change in the size of the manhole simply by increasing or decreasing the number of intermediate fence members.

Next, the pedestal B of the hanging tool attached on the protective fence A will be described.

The pedestal B is a pillar 40 standing on the cross member of the fence member.
The beam member 41 is installed between the pair of columns 40, 40.
There are two types of support columns 40, a long first support column 40a and a second support column 40b slightly shorter than the first support column 40a, both of which are attached to the lower end of a bar material such as a metal square pipe. Tool 42 is provided, and width adjusting plates 44, 44 having a plurality of bolt holes 43 opened laterally at a predetermined pitch are fixed to both side surfaces of the upper end. The embodiment of the fastener 42 shown in the drawings has the same structure as that used for clamping the scaffolding at a construction site, and has a semi-arcuate first grip 42a and the first grip 42a. The second grip portion 42b has a base end rotatably pivotally mounted, and a bolt 42c fastened to the tip end. The fastening tool 42 may have any configuration as long as the strut 40 can be detachably fastened to the cross member of the fence member.

On the other hand, the beam member 41 is provided between the first support columns 40a and 40a.
There is a beam member 41a and a second beam member 41b that is installed between the second support columns 40b and 40b. The first beam member 41a and the second beam member 41b are
In each case, a plurality of through bolt holes 45 ... Are opened at a predetermined pitch on the side surface of a bar material such as a metal square pipe, and the second beam member 41 is provided.
A top plate 46 is fixed to the center of the length of b. still,
Since the size of the opening of the manhole is standardized for the bolt holes 43, 45, ... Generally, it is preferable to open the bolt holes 43 at a pitch that conforms to this standard. Then, in the embodiment shown in the drawings, a rotation support shaft 50 is erected on the upper surface of a beam 49 for traveling a trolley 48 of a hoisting device 47 such as a hoist or a chain block, and the rotation support shaft 50 is arranged from the lower side to a first position. 2 beam members 41
b and the inside of each axial hole of the first beam member 41a, the first beam member
A nut 51 is screwed and fixed to the tip protruding from the upper surface of 41a. Therefore, the first beam member 41a, the second beam member 41b, and the beam 49 can be rotated about the rotation support shaft 50, and they can be folded in the same direction or in the drawing. As shown, the first beam member 41a and the second beam member 41b can be expanded in a cross shape. In addition, in order to reduce the rotation resistance, a bearing is interposed in the middle, and a hanging tool is used.
In preparation for eccentric load when 47 is positioned at the end of beam 49, ball type receiving part 5 is placed at a position off the center of the upper surface of beam 49.
2, 52 are provided, and the balls of each ball type receiving portion 52 are configured to contact the lower surface of the top plate 46.

To mount the gantry B having the above-described configuration on the protective fence A in the field, the upper ends of the first support columns 40a are arranged on both sides of the first beam member 41a and the upper ends of the second support columns 40b are arranged on both sides of the second beam member 41b. Tighten each with bolts and nuts. In this case, the bolts are installed by penetrating the through bolt holes 43, 45 ... Corresponding to the size of the opening of the manhole. In this way, the first support columns 40a, 40
a, After mounting the second strut 40b40b, the first beam member 41a and the second beam member 41b are spread out so as to be substantially orthogonal to each other, and in this state lifted and placed on the uppermost cross member of the protective fence A, each strut It is fixed to the cross member by the fastener 42 of 40 (Fig. 1). When the pedestal B is fixed on the protective fence A in this manner, even heavy objects such as pumps can be suspended by the suspenders 47 and lifted safely and easily from the manhole opening to the underground work site. be able to. Then, the suspension 47 is attached to the beam 49.
Since the beam 49 can be rotated around the rotation support shaft 50, the pump and the like can also be suspended by a wire or the like on the hook 47 'of the suspending tool 47. It can be done easily and safely. Hanging device 47
Even if is moved to the end of the beam 49, it stops by contacting the stopper 53, so it does not come off from the beam 49, and even if an eccentric load is applied, the ball type receiving part 52 is in contact with the top plate 46. , Safe.

Further, in the embodiment shown in the drawings, a suspension ring is provided on one side of the beam 49.
Since the 54 is provided, the declining machine 55 may be attached to the suspension ring 54 to ensure the safety of the worker. Quiet 55
If the worker should fall out of his or her feet, etc., the centrifugal clutch mechanism should stop the feeding of the wire rope 55 'that is attached to the waist of the worker, and then the rotation of the winding drum should be stopped. By controlling and rotating the winding drum at a low speed, the wire rope 55 'is unrolled at a very low speed, and the worker who is prevented from falling and is suspended in the air is slowly lowered.

Then, when the work is completed, the gantry B is removed from the protective fence A, and the first support column 40a and the second support column 40b are removed from the beam member 41 to be disassembled into a size that can be easily loaded on an automobile such as a light van. be able to.

Further, the protective fence A can also be easily disassembled and loaded on a car.

<Effects of the Invention> In short, according to the present invention, a fence for manholes, which comprises a plurality of fence-shaped fence members detachably connected in a generally cylindrical shape, comprising a plurality of upper and lower circles. Combining the arc-shaped horizontal members and the left and right vertical members to form a nearly shield type,
A supporting portion extending outward is provided at a lower portion between both vertical members, a door member is rotatably provided at an upper portion of one vertical member, and a receiving piece having a connection hole is provided at a lower portion. By providing a receiving piece having a connection hole in the vertical member on the side, the first fence member and the fourth fence member, which are substantially symmetrically formed with each other, as end fence members, and a plurality of upper and lower arc-shaped arc members. The horizontal members and the left and right vertical members are combined to form a nearly shield type, and a support part extending outward is provided in the lower part between both vertical members, and the left and right vertical members are adjacent fences. An intermediate part fence member provided with a receiving piece or a connecting portion for rotatably and detachably connecting the members, and a connector having an adjustable length, which is provided at an end with an engaging portion corresponding to a connecting hole of the receiving piece. And a first fence member and a fourth fence member, which are the above-mentioned fence members, are arranged such that the door members on one side are adjacent to each other, The above-mentioned connecting tool is attached between the receiving pieces of the end fence members to connect the ends of the end fence members in an adjustable manner, and the first fence member and the fourth fence member are the end fence members. At least one intermediate fence member is arranged in the other side space of the fence members, and adjacent fence members are rotatably and detachably connected to each other. When not in use, such as during transportation or storage, the connection member can be removed and the fence members can be disassembled to reduce the size. Therefore, it can be easily loaded into a work vehicle such as a light van and does not require a large space. On the other hand, when used in the field, the number of intermediate fence members can be increased or decreased to suit the size of the manhole, so even one set of protective fences A can have multiple types with different diameters. Can be used for manholes.

Further, particularly in the present invention, the first fence member and the fourth fence member, which are the end fence members, are arranged so that the door members on one side are adjacent to each other, and between the lower receiving pieces of both fence members. Since the space between the first fence member and the fourth fence member can be changed to a certain degree because the space on one side of both fence members can be adjusted by attaching the above-mentioned connecting tool, each fence can be irrespective of the diameter of the manhole. The support portion of the member can be securely and firmly held on the support step portion of the manhole. In addition, even if the operator opens and closes both door members, the lower coupling tool supports the left and right fence members, so they can fall and fall without going down and fall into the manhole very securely. The work safety can be ensured.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a front view of a protective fence with a pedestal fixed, and Fig. 2 is an expanded state in which four fence members are connected for use as a standard manhole. Fig. 3 is a front view of the protective fence in Fig. 3, Fig. 3 is a plan view of the protective fence shown in Fig. 2 assembled into a substantially cylindrical shape, Fig. 4 is a perspective view of a receiving piece, and Fig. 5 is a type 1 connecting member. 6 is a perspective view of FIG.
The figure shows the front view of the connecting tool, Fig. 7 shows the front view in the state of being connected by the third type connecting member, Fig. 8 shows the plan view of the protective fence shown in Fig. 7, and Fig. 9 is used for manholes of small diameter. In order to do this, a front view of the protective fence in the unfolded state in which three fence members are connected, Fig. 10 is a plan view of the protective fence shown in Fig. 9 assembled into a substantially cylindrical shape, and Fig. 11 shows a large diameter. Front view of the protective fence in the deployed state with five fence members connected for use in a manhole, Fig. 12 is a plan view of the protective fence shown in Fig. 11 assembled into a substantially cylindrical shape, and Fig. 13 is A front view of the gantry in an assembled state, FIG. 14 is a plan view of the gantry shown in FIG. 13,
FIG. 15 is a side view showing an operating state of the fastener. In the figure, 1 and 4 are end fence members, 2, 3 and 34 are middle fence members,
5,12,18,21 are horizontal members, 6,13,19,22 are vertical members, 7,14,20,23 are supporting parts, 8,15,24,38 are fall prevention wall members, and 9a, 9b are Door member, 1
Reference numeral 1 is a receiving piece, 17, 25, 32 are connecting members, and 29 is a supporting step.

Claims (1)

[Scope of utility model registration request] 1. A manhole protective fence in which a plurality of fence-shaped fence members are detachably connected in a substantially cylindrical shape, and comprises a plurality of upper and lower arc-shaped horizontal members and left and right vertical members. Combined with the material, it is formed into a nearly shield type, and a support part extending outward is provided in the lower part between both vertical materials, and the door member can be rotated on the upper part of one vertical material And a receiving piece having a connecting hole in the lower portion and a receiving piece having a connecting hole in the vertical member on the other side, the first fence as an end fence member formed substantially symmetrically to each other. The fence member and the fourth fence member are combined with a plurality of upper and lower arc-shaped horizontal members and left and right vertical members to form a nearly shield type and to extend outward in the lower part between both vertical members. An intermediate part that is provided with a support part that extends and a receiving piece or a connecting part that rotatably and detachably connects the adjacent fence members to the left and right vertical members. A first fence member and a fourth fence member, which are the end fence members, including: a fence member; and a connector having an adjustable length provided at an end thereof with an engaging portion corresponding to the connection hole of the receiving piece. To
While arranging the door members on one side so as to be adjacent to each other, the connecting tool is attached between the receiving pieces of the fence members for the ends to connect the ends of the fence members for the ends in an adjustable manner, Further, at least one intermediate fence member is arranged in the other side space between the first fence member and the fourth fence member, which are the end fence members, so that adjacent fence members can be rotated. And a manhole protection fence that is detachably connected.