JP6975455B2 - Safety fence device for manholes - Google Patents

Description

The present invention relates to a manhole safety fence device for inspection / repair work of sewers, underground power cables, communication cables, gas pipes, and the like.

Normally, a manhole opens on the ground surface such as a road, and the opening is provided with a cast iron lid plate that closes the vertical hole.
The maintenance and inspection of the underground facility having the manhole is performed by opening the lid plate and the worker entering the manhole, and normally, the lid plate is kept open during the work. In this open state, workers, road passers-by, etc. may accidentally fall into the manhole.

For this reason, conventionally, a safety fence is used to surround the opening of an open manhole to prevent it from falling.
As the safety fence device, there is one provided with a movable strut provided on a ladder in the vertical direction in a manhole so as to be able to move up and down, and a safety fence on the movable strut (Patent Document 1, FIGS. 1 to 4).
Further, there is a ladder provided with a handrail provided on the upper part of the ladder column so as to appear and disappear, and a fall prevention fence provided on the upper end of the ladder column so as to be undulating (Patent Document 2, FIGS. 2 to 10).

Japanese Unexamined Patent Publication No. 09-279615 Japanese Unexamined Patent Publication No. 2013-249626

All of the above safety fence devices are provided with measures to prevent the safety fences and the like from falling into the manhole when the safety fences and handrails are pulled up from the ladder columns and erected on the ground surface. The preventive measure is to use a pin that can be inserted and removed between the safety fence and the ladder column (see reference numerals 9 and 10 in Patent Document 1), or by locking a stopper piece of the handrail column to the upper end of the ladder column. (Refer to reference numeral 20 and the like in Patent Document 2).
The fall prevention means using these pins and stopper pieces is unique to prevent the safety fence from descending, and there are some that the operator does not forget and automatically operates. ..

By the way, when a worker goes in and out of a manhole, it is common practice to use a commercially available fall prevention device (safety block) in order to avoid the danger of falling due to slipping of limbs or the like. The fall prevention device is used when going up and down a high-altitude work place such as a ladder or a utility pole.The block body is fixed to a fixed object, and the wire rope tied to the worker can be drawn out from the block. Even if the worker should step off, the wire rope will stop feeding instantly to mitigate the crash.

It is possible to fix this fall prevention device to a part of the safety fence of the safety fence device, but the fixed state is unstable, and the conventional safety fence is in the event of a worker's crash. It is not a structure that can withstand. For this reason, an out-trigger that can appear and disappear from the inside to the outside is provided at the lower end of the gate-shaped part of the safety fence, and when the safety fence is pulled out from the manhole, the out-trigger is projected outward from the safety fence and is located on the upper surface of the side wall of the manhole. It is conceivable that the gate-shaped portion is stably fixed to the ground (upper surface of the manhole side wall).

It is an object of the present invention to ensure that the outriggers can be operated under the above circumstances.

In order to achieve the above object, the present invention has an outrigger interlocked with a lock pin.
As described above, the lock pin, whether manual or automatic, always operates to prevent the safety fence from descending. Therefore, if the outrigger operates in conjunction with it, the outrigger also exerts its action (function).

A specific configuration of the present invention includes a movable strut provided on a ladder in the vertical direction in a manhole so as to be able to move up and down, a safety fence provided on the movable strut, a lock pin, and an out trigger interlocking with the lock pin. The lock pin can be attached to and detached from the ladder by the operating rod provided on the safety fence, and when the safety fence is in the manhole, it slides on the ladder and when the safety fence is pulled out from the manhole, The actuating rod locks to the ladder to prevent the safety fence from descending, and the out trigger is located in the manhole when the lock pin is sliding on the ladder, and the lock pin is located in the manhole when the lock pin is locked to the ladder. It is possible to adopt a configuration in which the manhole is locked to the upper end of the manhole in conjunction with the above.

The safety fence usually has a gate-shaped part, and a fall prevention device (safety block) is attached (fixed) to the side rod of the gate-shaped part, and a worker can use a manhole through the fall prevention device. You will go in and out. At this time, since the outrigger is locked to the upper end (upper surface of the side wall) of the manhole in conjunction with the lock pin, the safety fence is stable and can be a sufficiently fixed object of the fall prevention device.
Further, when the safety fence is pulled out from the manhole, the lock pin may be locked to the upper end of the manhole or the like to prevent the safety fence from descending. Therefore, in the present invention, when the lock pin is locked to the ladder. Is not only when the lock pin is locked to the upper end (upper surface) of the ladder or to the upper surface of the manhole, but also when it is not the absolute upper end of the ladder, a notch or protrusion in the middle, etc. It shall also include locking with a part where the lock pin of the manhole can be locked to prevent the safety fence from descending.

In this configuration, the lock pin is urged toward the ladder by a spring, and when the safety fence is pulled out from the manhole, the lock pin reaches the upper end of the ladder and is further slid to the ladder by the spring. It is possible to move in the direction toward the ladder and lock it to the upper end of the ladder (including the upper surface of the manhole).
In this way, the lock pin and outrigger can be automatically actuated by the spring.

The lock pin and the outrigger may be interlocked by an appropriate means, but for example, they may be interlocked by a link mechanism.

Since the present invention is configured as described above and the outriggers are interlocked with the lock pins, it is possible to stabilize the safety fences by the outriggers at the same time as the fall prevention action of the safety fences by the lock pins. Therefore, a safer safety fence device can be obtained.

The installation state of the safety fence in the manhole of the embodiment of the safety fence device according to the present invention is shown, (a) is a stored state, and (b) is a pulled-out state. Partial side view seen from the left side of FIG. 1 (b) The plan view which opened the lid plate of FIG. 1 (b) Perspective view of the main part of the same embodiment Partial perspective view of the same embodiment It is a partial action diagram of the same embodiment, (a) is a perspective view, (b) is a cut plan view.

An embodiment of the safety fence device according to the present invention is shown in FIGS. 1 to 6, and a ladder H in the vertical direction is installed on the inner wall of the manhole M up to the bottom of the manhole as in the conventional case. In the safety fence device A of this embodiment, the movable columns 11 and 11 provided on the columns 1 and 1 on both sides of the ladder H so as to be able to move up and down, the safety fence 20 provided between the two movable columns 11, and the movable one. It has a lock pin 30 provided on the support column 11 and an outrigger 40 interlocked with the lock pin 30.

In the ladder H, cross rails (step plates) 2 are provided on the columns 1 and 1 on both sides at appropriate intervals, and the upper end thereof is on the inner wall of the manhole M and the lower end thereof is on the bottom surface of the manhole M. Each is fixed via. The worker goes in and out of the manhole M with this ladder H.
The safety fence 20 has a cylindrical shape along the inner peripheral wall of the manhole M including a substantially arcuate cross rail 21 and a vertical rail 22 connecting the cross rails 21, and a part of the cylindrical shape is cut out. It becomes a doorway, and workers can freely enter and exit from the doorway (notch).

In this embodiment, a lid plate 4 that also serves as a manhole cover is provided on the upper surface of the safety fence 20 so as to be undulating via a hinge 5, and the lid plate 4 has a freely undulating handle (not shown). From the state where the safety fence 20 shown in FIG. 1 (a) is contained in the manhole M, the safety fence 20 is lifted as shown in FIG. 1 (b). At this time, the lid plate 4 is prevented from being easily opened (not opened) by a hook or the like on the safety fence 20.

If the safety fence 20 is lifted (pulled out from inside the manhole), as shown by the chain line in FIG. 1 (b), the lid plate 4 is erected by unlocking the hook or the like (not shown). Maintains and locks its upright position. The lid plate of the manhole M may be different from the lid plate 4 of the safety fence 20 (see the lid 2 of Patent Document 1 and the fall prevention fence 2 of Patent Document 2). In this case, the safety fence 20 can omit the lid plate 4, and the upper end portion is appropriately grasped and raised and lowered, and the manhole cover (cover plate) is removed from the opening of the manhole M before the raising and lowering. Will be.

The movable strut 11 has a side plate 11a inside thereof, and an operating rod 12 in the length direction is provided on the side plate 11a of the movable strut 11 via a bearing piece 12a so as to be rotatable around its axis and unable to fall in the vertical direction. (See FIG. 5), a handle 13 is integrally provided at the upper end of the operating rod 12, and a lock pin 30 is integrally provided at the lower end.
A projecting piece 15 is provided in the middle of the operating rod 12, and springs 14 such as torsion springs are provided above and below the projecting piece 15. The urging force of the spring 14 urges the lock pin 30 toward the ladder column 1 (clockwise in FIG. 6B). The number of springs 14 may be one as long as sufficient urging force is obtained to rotate the lock pin 30 and the outrigger 40.

Since the operating rod 12 can rotate around its axis, the lock pin 30 can be attached to and detached from the movable column 11 and the ladder column 1, and the safety fence 20 shown in FIG. 1A is a manhole. When entering the M, the urging force of the spring 14 slides to one corner of the ladder support 1 and moves up and down (see the chain line state in FIG. 5). On the other hand, when the safety fence 20 shown in FIG. 1B is pulled out from the manhole M, the lock pin 30 reaches the upper end of the ladder support 1 and is further rotated by the spring 14 toward the upper surface of the ladder support 1. (From the chain line in FIG. 5 to the solid line, from the solid line in FIG. 6 (b) to the chain line).
When the lock pin 30 rotates toward the upper surface of the ladder column 1, the lock pin 30 is locked to the upper surface of the ladder column 1. This locking prevents the safety fence 20 from descending. At this time, as shown in FIGS. 5 and 6B, if the stopper piece 31 is provided on the upper surface of the ladder column 1, the lock pin 30 and the upper surface of the ladder column 1 are stably locked.

As shown in FIGS. 4 and 5, the outriggers 40 are provided on the vertical rod 23b of the safety fence 20 so as to be able to appear inside and outside the safety fence 20 via a support shaft 41 along the vertical direction. As shown in the figure, the support shaft 41 is connected to the operating rod 12 by the link mechanism 42, and the outrigger 40 rotates via the support shaft 41 in conjunction with the operating rod 12 by the link mechanism 42. do. The link mechanism 42 has a link 42a fixed to the support shaft 41 of the outrigger 40, an L-shaped link 42b fixed to the operating rod 12 of the lock pin 30, and an arc shape rotatably connected to both links 42a and 42b. It consists of a link 42c (see FIG. 5).

By interlocking the lock pin 30 and the out trigger 40 by the link mechanism 42 in this way, as shown in FIG. 6 (b), the safety fence 20 shown in FIG. 1 (a) is housed in the manhole M. In the middle of lifting the safety fence 20, the lock pin 30 abuts against the spring 14 against the side surface (one corner) of the ladder support 1 and slides. At this time, since the link mechanism 42 also does not move, the outrigger 40 is located in the safety fence 20 (inside the manhole M) (FIG. 5 chain line state).

When the lock pin 30 reaches the upper surface (upper end) of the ladder support 1, it rotates as shown by the chain line in FIG. 6B due to the urging force of the spring 14 and rotates until it hits the movable support 11. Locks on the top surface.
Along with the rotation of the lock pin 30, the operating rod 12 integrated with the lock pin 30 also rotates, and with the rotation of the operating rod 12, the link mechanism 42 moves from the chain line in FIG. 5 as shown by the solid line, and the outrigger 40 also rotates. It protrudes to the outside of the safety fence 20.

The lock pin 30, the outrigger 40, the link mechanism 42, and the operating rod 12 are provided symmetrically on both the left and right sides of the safety fence 20 (see FIG. 4).

This embodiment has the above-mentioned configuration, and the operation thereof will be described next. First, as shown in FIGS. 1A to 1B, the lid plate 4 is lifted by its handle, and the safety fence 20 is pulled up from the manhole M. At this time, if the ladder H (the column 1 thereof) is provided with the elevating device including the counterweight, the wire, etc. described in Patent Document 2, the pulling operation is simple and smooth.

Next, as the safety fence 20 is pulled up, the lock pin 30 rises while sliding at one corner of the ladder support 1 (in the state of the chain line in FIG. 5) to reach the upper end of the ladder support 1, FIG. 1 (b). As shown in FIGS. 5 and 6 (b), the restraint at one corner is released, and the spring 14 rotates to the outside of the safety fence 20 and locks it to the upper surface of the ladder support 1. Along with the operation of the lock pin 30, the outrigger 40 is also rotated outward by the link mechanism 42 and locked to the upper surface of the manhole (the peripheral edge of the manhole opening formed by the reinforcing frame W). By both locking, the safety fence 20 is fixed (set. Solid line state in FIG. 4) to the upper surface of the manhole M.

In this way, the safety fence 20 is attached and fixed to the upper part of the manhole M by the automatic double lock by the lock pin 30 and the outrigger 40. In this state, the operator removes the chain T, fixes the fall prevention device (safety block B) to the horizontal rod 23a forming the gate-shaped member of the safety fence 20 (see FIGS. 2 and 4), and the fall prevention device. Grasp the handle or the like through B and enter the manhole M with the ladder H to perform the work. At this time, the safety fence 20 (particularly, the gate-shaped portion of the vertical rod 23b provided with the outrigger 40 shown in FIG. 4 and the horizontal rod 23a above the vertical rod 23b) is stably fixed to the upper surface of the peripheral wall of the manhole M by the outrigger 40. Therefore, even if the worker should step off the foot, the fall prevention device B does not move stably and the wire rope instantly stops feeding to alleviate the fall. The gate-shaped horizontal rods 23a and vertical rods 23b are provided separately from the horizontal rails 21 and the horizontal rails 22 of the safety fence 20, and the horizontal rails 21 and the horizontal rails 22 are used as gate-shaped members for the outrigger 40 in terms of strength. It can also be used as long as it can be used.

When the work is completed and the worker exits the manhole M, when the operating rod 12 is turned counterclockwise against the spring 14 with the handle 13, the lock pin 30 also rotates in the same direction and the ladder support 1 Release the lock with the upper surface. Further, as the operating rod 12 rotates, the outrigger 40 also rotates by the link mechanism 42 and moves out from the upper surface of the manhole (reinforcing frame W) into the safety fence 20 (Fig. 4, chain line state).
The safety fence 20 can be lowered by releasing the lock between the lock pin 30 and the upper surface of the ladder support 1 of the outrigger 40 and the upper surface of the manhole. Therefore, by pressing the lid plate 4, the safety fence 20 is pushed into the manhole M and stored. When the lid plate 4 fits in the manhole M, the storage is completed.

As shown in FIGS. 5 and 6B, the lock pin 30 and the upper surface of the ladder support 1 are unlocked until the lock pin 30 gets over the stopper piece 31 if there is a stopper piece 31. After pulling up the operating rod 12, it is rotated to hit the ladder support 1. When the stopper piece 31 is provided, the safety fence 20 is pulled up to a position where the lock pin 30 can get over the stopper piece 31 so as to be locked to the upper surface of the ladder support 1.

In the above embodiment, the operating rod is urged by the spring 14, but the lock pin 30 and the outrigger 40 are mounted on the upper surface of the ladder support 1 by omitting the spring 14 and manually rotating the operating rod 12. And it can be locked to the upper surface of the manhole M and can be released from the lock. However, according to the spring 14, the locking pin 30 and the outrigger 40 are automatically locked to the upper surface of the ladder column 1 and the upper surface of the manhole M by the urging force, and the locking is maintained, so that it is safe. be. The spring 14 may be provided with a torsion spring on the support shaft 41 of the outrigger 40, or a coil spring or the like may be provided on the link mechanism 42, as in the embodiment provided around the operating rod 12.
Further, if the safety fence 20's descent prevention function and the worker's fall prevention function (stabilization of the safety fence) can be exerted, the lock pin 30 and the outrigger 40 may be on only one side of the safety fence 20 instead of both sides. ..

The above embodiment is a manhole M having a circular shape in a plan view, but it goes without saying that the present invention can be adopted for manholes having various plane shapes such as a square shape in a plane view. At that time, it goes without saying that the shape of the safety fence 20 and the like corresponds to the planar shape of the manhole.
Thus, the embodiments disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is indicated by the scope of claims and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Ladder support 2 Horizontal rail (step board)
4 Cover plate 11 Movable support 12 Acting rod 13 Handle 14 Spring 20 Safety fence 21 Horizontal rail 22 Vertical rail 23a Horizontal rod of gantry member 23b Same vertical rod 30 Lock pin 40 Outrigger 41 Outrigger support shaft (rotary shaft)
42 Link mechanism A Safety fence device M Manhole H Ladder T Chain

Claims (3)

A movable column (11) provided on a vertical ladder (H) in a manhole (M) so as to be able to move up and down, and a safety fence (20), a lock pin (30) and a lock pin thereof provided on the movable column (11). It has an outrigger (40) interlocked with (30) and has an outrigger (40).
The lock pin (30) can be brought into contact with and detached from the ladder (H) by the operating rod (12) provided on the safety fence (20), and the safety fence (20) becomes the manhole (M). When it is inside, it slides on the ladder (H), and when the safety fence (20) is pulled out from the manhole (M), it is locked to the ladder (H) by the operating rod (12) and the safety fence (H). Prevent the descent of (20) and
The outrigger (40) is located in the manhole (M) when the lock pin (30) is sliding on the ladder (H), and when the lock pin (30) is locked to the ladder (H). A manhole safety fence device that locks to the upper end of a manhole (M) in conjunction with the lock pin (30). The lock pin (30) is urged toward the ladder (H) by a spring (14), and when the safety fence (20) is pulled out from the manhole (M), the ladder (H) The manhole safety fence according to claim 1, wherein the spring (14) reaches the upper end and moves from sliding to the ladder (H) toward the ladder (H) and is locked to the upper end of the ladder (H). Device. The manhole safety fence device according to claim 1 or 2, wherein the lock pin (30) and the outrigger (40) are connected and interlocked by a link mechanism (42).

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