JP3766328B2 - Fall prevention net for underground structures - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention has, on the inner periphery, a slanted wall portion whose upper portion is inclined outward, and a shift stopper that protrudes downward to position the lid receiving frame on the installation portion, and has a lateral concave portion or convex portion. The present invention relates to a fall prevention net for an underground structure applied to a lid receiving frame that does not have.
[0002]
[Prior art]
There is a device for preventing a person or an object from falling at an opening portion for approaching the inside of an underground structure, which is known as a fall prevention frame or a fall prevention lid. This type of device is attached to the lid receiving frame, and in many cases, it is attached so that it does not come out downward or upward using a lateral recess provided on the inner periphery of the lid receiving frame. It has been. There are many examples of this, such as Noto 3063351 and JP-A-2001-32305. Japanese Patent Application Laid-Open No. 2000-291035 uses a convex portion in the horizontal direction, so it is necessary to provide engaging means at the top and bottom. In common.
[0003]
However, there are lid receiving frames that do not have lateral recesses or projections, and some that are not suitable for mounting the fall prevention nets even if there are irregularities. Among them, in the case of Japanese Patent Application Laid-Open No. 2001-146757, the fitting shaft of the portable ladder is fitted into the mounting hole provided on the inner periphery of the lid receiving frame, and is similarly provided on the inner periphery. It is taking a method of fixing the portable ladder using an attachment to the handle. As in this example, when mounting holes and handles are used for mounting a portable ladder, the mounting position is shifted, and a large margin of strength is taken to compensate for the mechanical imbalance caused thereby. You will accept disadvantages such as need.
[0004]
[Problems to be solved by the invention]
The present invention has been made paying attention to the above-mentioned points, and the problem is that it is stably attached to a lid receiving frame that does not have or does not have a concave or convex portion in the lateral direction. And a fall prevention net for an underground structure that can be easily attached and detached.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention includes a net body that substantially covers the entire inside of the lid receiving frame, and applies a pressing load applied to the net body by engaging with the slant wall portion of the lid receiving frame from above. An upper receiving portion is provided on the net body, and a lower receiving portion is provided on the net body to counter the push load applied to the net body by engaging with the stopper of the lid receiving frame from below, and further the upper receiving portion or the lower receiving portion. Means is provided in which at least one of the parts is movably provided.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The fall prevention net for an underground structure according to the present invention has, on the inner periphery, a slanted wall portion whose upper portion is inclined outward, and a shift stopper protruding downward to position the lid receiving frame on the installation portion. And it is applied to the lid receiving frame which does not have a horizontal recessed part or convex part. The lid receiving frame having the inclined wall portion is typically a frame having a tapered receiving surface that constitutes the invention of Registration No. 1576533 related to the creation of the applicant company. However, the inclination does not need to extend over the entire circumference as in the tapered receiving surface, and the present invention can be applied to a lid receiving frame having a partially inclined wall portion.
[0007]
The slip stopper protrudes downward, and is a portion that can be engaged with a hole edge of an installation portion called a lower gutter, a side block, or an adjustment frame for installing the lid receiving frame. Such a detent may be cast integrally with the frame body in a state of being located on the inner periphery of the frame opening of the lid receiving frame and projecting downward from the frame body. Note that the present invention can be applied to a lid receiving frame that does not have a lateral recess or projection, but this must be one that does not have a lateral recess or projection. This does not mean that the present invention is not applicable, and the present invention can be applied even if it has a concave portion or a convex portion in the horizontal direction.
[0008]
In contrast to this lid receiving frame, the present invention includes a net body that substantially covers the entire inside of the lid receiving frame. The net body is a main body of the fall prevention net, and has a mesh that can cover the entire inside of the lid receiving frame or the frame opening of the lid receiving frame to prevent a person or an object from falling. However, the term “network” does not impose any restrictions other than the above-described fall prevention, and may be considered to refer to the same thing as the fall prevention frame, the fall prevention lid, and the like.
[0009]
Then, an upper receiving portion is provided on the mesh body to engage the slanted wall portion of the lid receiving frame from above and support the downward load applied to the mesh body from above, and is also engaged from below to prevent the lid receiving frame from shifting. The net body is provided with a lower receiving portion that resists the pushing load applied from below to the net body. That is, the inclined wall portion is used to receive the push-down load, and the slip stopper is used to receive the push-up load.
[0010]
Further, at least one of the upper receiving portion and the lower receiving portion is provided to be movable. The purpose of making it movable is to make the upper receiving part engaged with the inclined wall part, or to switch to the non-engaging state from that, or to make the lower receiving part engaged with the slip stopper Either to switch to the disengaged state. Furthermore, means for attaching and detaching the net body can be provided.
[0011]
Some lid receiving frames have a step frame provided on the inner periphery so as to protrude inward. A mechanism for rotating the fall prevention net up and down is provided using the structure of the lid receiving frame. It becomes possible to open the frame opening of the frame. For this purpose, a bearing portion is provided on the net body so that the net body can be rotated with a part of the step frame as a rotation axis. Since it is a design matter whether the fall prevention net is rotated and set up or is further reversed, it can be arbitrarily selected. The bearing part provided on the net body is a type of joint, so it is also expected to play a role in securing the fall prevention net to the lid receiving frame, especially when the fall prevention net pops out from the inside of the underground structure. It will be against the power to try.
[0012]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. FIG. 1 shows a plan view of the present invention, and FIG. 2 shows a longitudinal sectional view. In each figure, 11 is a lid receiving frame, 12 is a slanted wall portion with an upper portion inclined outward and 13 is a displacement stopper provided as a positioning at the lower portion of the inner periphery.
[0013]
The slip stoppers 13 are provided at three positions in the frame opening of the lid receiving frame 11 at equal intervals in the circumferential direction, and protruded downward so as to engage with the hole edge of the installation portion 14 on which the lid receiving frame 11 is placed. It is formed in a shape. The illustrated lid receiving frame 11 has a step frame 15 for entering and exiting into the frame opening on the inner periphery thereof, and the position of the step receiving frame 11 is overlapped with the position of one shift stopper 13. The step frame 15 is at a relatively low position in the lid receiving frame.
[0014]
The fall prevention net 16 includes a net body 17 having a shape and a structure that substantially covers the entire inner surface of the lid receiving frame 11. The illustrated net body 17 includes an arc-shaped outer frame 18 a and a net-like inner frame 18 b provided therein, and the outer frame 18 a is accommodated in the narrowest portion in the lid receiving frame, and is a part of the step frame 15. Then, it has a portion with a reduced diameter inside, and also has a recess 19 for avoiding a conflict with the internal structure of the lid receiving frame when it is raised centering on a relatively low position. See FIG. 3 and FIG.
[0015]
The net body 17 is provided with a plurality of receiving pieces 21 having inclined surfaces that are adapted to the inclination of the inclined wall portion 12 at substantially equal intervals as upper receiving portions that can be engaged with the inclined wall portion 12 of the lid receiving frame 11 from above. The frame 18a protrudes outward. The net body 17 has a plurality of latching pieces 22 that are hooked under the stopper 13 as lower receiving portions that can be engaged with the stopper 13 of the lid body 11 from below. In order to attach and detach the net body 17, the hooking piece 22 as a lower receiving portion is provided so as to be movable inward and outward of the net body 17.
[0016]
5 and 6 exemplify a configuration for that purpose. The latch piece 22 has a slide portion 23 at the top, and a long hole 25 in the inner and outer directions of the substrate 24 attached to a corresponding position on the net body side. And is stopped at an arbitrary position by set screws 26 and 27. The slide portion 23 is easily handled when it is held by a slide receiver 28 formed by bending both sides of the substrate 24.
[0017]
Furthermore, a pair of locking members 29 serving as bearings are provided on the net body 17 in order to rotate the net body 17 with a part of the step frame 15 as a rotation axis. The illustrated locking member 29 has a shape like a substantially inverted U-shaped clamp that is hung on the step frame 15, and has a bolt 31 and a nut 32 on the opening side as a stopper. The fall-preventing net 16 is always fixed to the lid receiving frame 11 by the locking member 29. For this reason, the illustrated bearing portion also serves as a substitute for the upper receiving portion and the lower receiving portion. In other words, as shown in FIGS. 1 and 3, the exemplary fall prevention net is provided with an upper receiving portion and a lower receiving portion on the left half and a bearing portion on the right half to balance the whole. It is the composition which takes.
[0018]
The pair of locking members 29, 29 are arranged near both corners of the step frame 15, thereby preventing the fall prevention net 16 from moving sideways. By preventing this movement, there is no possibility that the latching piece 22 is detached from the detent 13 and the safety against the push-up load of the fall prevention net 16 is further ensured. That is, the pair of locking members 29, 29 and the step frame 15 constitute a movement preventing means for the fall prevention net 16.
[0019]
At the time of installation, the bolt 31 and the nut 32 are removed, the fall prevention net 16 is locked to the step frame 15 at the portion of the locking member 29, the latching piece 22 is moved backward and then moved forward, The stopper 13 is attached to the lid receiving frame 11 by engaging with the lower end of the stopper 13 and tightening the set screws 26 and 27. It is the state of FIG. The fall prevention net 16 is firmly fixed to the lid receiving frame 11 by an upper receiving portion and a lower receiving portion, and can withstand a push-down load and a push-up load. Further, as shown in FIG. 6, when the bolts 26 and 27 are loosened and the hooking piece 22 is retracted inward, the fall prevention net 16 is rotated around the step frame 15 as an axis, and is raised and closed. The inside of the frame can be opened. See FIG.
[0020]
【The invention's effect】
Since the present invention is configured and operates as described above, the fall prevention net can be easily and stably provided on the lid receiving frame which has or does not have a lateral concave portion or convex portion. Since the upper receiving part engages with the slanted wall part, the stability at the time of engagement is good, and the lower receiving part engages with the stopper so that the reliability is high and the entrance and exit to the manhole, etc. It can be opened or removed as necessary, and the entire fall-preventing net is attached to the lid receiving frame, so that the balance at the time of mounting is good.
[Brief description of the drawings]
FIG. 1 is a plan view showing an embodiment of a fall prevention net for underground structures according to the present invention.
2 is a cross-sectional view taken along the line II-II in FIG.
FIG. 3 is a plan view of the fall prevention net.
4 is a side view of FIG. 3; FIG.
FIG. 5 is an enlarged view of a main part of FIG.
FIG. 6 is a cross-sectional view showing an engaged state and a disengaged state of a lower receiving part.
FIG. 7 is an explanatory cross-sectional view showing a state in which a fall prevention net is raised.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Lid receiving frame 12 Slanting wall part 13 Stopper 14 Installation part 15 Step frame 16 Fall prevention net | network 17 Net | network main body 21 Receiving piece 22 as an upper receiving part Lowering piece 29 as a lower receiving part Locking member used also as a bearing part

Claims (2)

On the inner periphery, it has a slanted wall part whose upper part is inclined outward, and a detent that protrudes downward to position the lid receiving frame on the installation part, and does not have a lateral concave part or convex part. A fall prevention net applied to the lid receiving frame, comprising a net body that substantially covers the entire inside of the lid receiving frame, and being pushed down applied to the slant wall portion of the lid receiving frame from above. An upper receiving portion for supporting a load is provided on the net body, and a lower receiving portion is provided on the net body to engage with the stopper of the lid receiving frame from below and resists a pushing load applied to the net body. A fall prevention net for underground structures, wherein at least one of the lower receiving portions is movably provided. The lid receiving frame has a step frame provided on its inner periphery so as to protrude inward, and a bearing portion that allows the net body to rotate up and down with a part of the step frame as a rotation axis. The fall prevention net for an underground structure according to claim 1 provided on the net body.

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