JPH0567649U - Manhole cover - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an upper lid that can be safely and efficiently opened in a manhole. [Structure] A circular manhole top cover in which at least four or more even numbered keyholes 1a are provided at positions near the periphery of the top cover 1 at substantially equal intervals on the circumference.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a manhole top cover with improved safety and workability when opening and closing an iron cover (top cover) used for a manhole.

[0002]

[Prior Art]

 As for the opening of the conventional manhole iron cover, generally, as shown in FIG. 3 (a), the upper cover 1 is pulled and opened in the keyhole direction. In FIG. 3, 1 is a manhole top cover, 2 is a safety cone arranged around the manhole, 3 is a flash bar connecting the safety cones, and 4 is a running vehicle.

To remove the manhole top cover, one operator uses the lever principle as shown in FIG. 4 (a) and two workers as shown in FIG. 4 (b). There is a way to pull up. In this case, if the direction of the keyhole on the manhole cover is perpendicular to the direction of the road as shown in Fig. 5, the worker will be a little out of the safety cone and flash bar, and the work It was dangerous, and in this case it was necessary to correct the keyhole direction so that it was parallel to the road direction before opening.

[0004]

[Problems to be solved by the device]

 In this way, the conventional method has a low work efficiency, requires a long working time on the road, and has an unreasonable posture control when operating the keyhole, which puts a strain on the waist and is extremely dangerous. It is a task. The present invention has been proposed to improve the above-mentioned drawbacks, and an object of the present invention is to provide a manhole top cover that is safe and has a high work efficiency and can perform work smoothly.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention has devised a circular manhole cover characterized in that at least four or more even numbered keyholes are provided at positions near the periphery at substantially equal intervals on the circumference. This is the summary.

[0006]

[Action]

 According to the present invention, the number of keyholes on the manhole cover is four or more, so that the work can be performed efficiently without shifting the positions of the keyholes.

[0007]

【Example】

 Next, an embodiment of the present invention will be described. FIG. 1 shows an embodiment of the upper lid of the present invention, in which 1 is a manhole upper lid, 1a is a keyhole, 2 is a safety cone, 3 is a flash bar, and 4 is an automobile. In this case, even if one set of keyholes is at a right angle to the road, the other set is parallel to the road, and therefore work can be performed without shifting the direction of the keyholes 1a of the top cover 1. As shown in FIG. 2A, even if the direction of the keyhole is slightly deviated, the work can be performed without any trouble. FIG. 2B shows a case where the number of keyholes is six. If the number of keyholes is an even number, it may be 8 or more.

[0008]

[Effect of the device]

 As described above, according to the present invention, since the number of keyholes in the manhole is many, that is, an even number of four or more, one set of the keyholes is in a state of being oriented generally parallel to the length direction of the road. , The keyway direction is perpendicular to the direction of the road as in the past, which reduces the burden on the waist caused by an unreasonable posture when operating the keyhole, improves work efficiency, and further improves safety at road work sites. It has the effect of ensuring the security. It is needless to say that the present invention is not limited to a communication manhole, and any circular manhole cover can be applied.

[Brief description of drawings]

FIG. 1 shows a manhole cover of the present invention.

FIG. 2 shows the position of the keyhole on the manhole cover,
(A) shows the case where there are four keyholes, and (b) shows the case where there are six.

FIG. 3 shows a conventional example.

FIG. 4 shows opening work of the upper lid, (a) shows a case where there is one worker, and (b) shows a case where there are two workers.

FIG. 5 shows a conventional example in which keyholes are arranged at right angles to the direction of the road.

[Explanation of symbols]

 1 Manhole cover 1a Keyhole 2 Safety cone 3 Flash bar 4 Automobile

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Kazuhisa Matsuda 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (1)

[Scope of utility model registration request] 1. A circular manhole top cover, characterized in that at least four or more even numbered keyholes are provided at positions near the periphery at substantially equal intervals on the circumference.