JPS6019156Y2 - Manhole cover structure - Google Patents

Description

[Detailed Description of the Invention] Conventional manhole covers had a skewer-receiving structure in which a stepped portion was provided protruding from the inner edge of the manhole receiving frame, and the lid was held in place by the stepped portion.

First of all, because it is a skewer type, there is play between the lid and the receiving frame, and there is no digging, and the strength of the manhole cover is not affected by the receiving frame and is due to the strength of the cover alone, which makes it difficult to increase the size of the manhole. At the same time, the lid must also be made thicker, which results in disadvantages in terms of manufacturing, cost, transportation, etc., and in order to solve this problem, the applicant has developed a structure that increases the thickness of the lid and the receiving frame. We have developed a structure in which the peripheral edge is inclined and these are attached so that they can fit freely (hereinafter simply referred to as steep slope receiving structure), and we have achieved results such as no looseness, sufficient biting, substantial strength enhancement of the lid, cost reduction, etc. However, this had the disadvantage that the lid was difficult to open due to the large biting depth, and the crowbar hole for opening the lid was also provided on the outer edge of the lid, so the angle of inclination for inserting the crowbar was approximately 45mm.
A technical problem has arisen in that the vertical force required to lift the lid is small, making it difficult to open the lid.

The present invention utilizes the advantages of the steep slope bearing structure developed by the applicant, which eliminates the drawbacks of the conventional skewer type structure, and also solves the technical problems of this steep slope bearing structure, making it easy to handle even if there is a bite. The aim is to provide a manhole cover structure with a new concept that allows the cover to be opened.

In this invention, a lid 3 whose outer peripheral edge is inclined at the same inclination angle as that of the lid receiving part 1 is attached to a receiving frame 2 having an inclined lid receiving part 1 so as to be freely fit therein, and a plurality of crowbars are attached to the outer peripheral part of the M3. Hole 1
This relates to a manhole cover structure in which a recessed portion 4 is formed in the inner peripheral portion of the receiving frame 2 at a position facing the burl hole.

In the figure, 5 is the lid hinge hardware, 6 is the insertion hole for the opening lid hinge hardware provided on the receiving frame 2, 7 is the lid rib, 8 is the receiving frame reinforcing rib, 9 is the crowbar, and 10 is the crowbar hole provided on the lid side. be.

The inclination angle of the lid receiving part 1 is preferably (5° to 100°) in terms of strength, bite, etc.

Further, the opening formed by the recessed portion 4 and the burl hole 10 provided on the lid side is used as the burl hole.

The number of recesses 4 in the receiving frame 2 facing the burl holes 10 in the lid 3 varies depending on the size and shape of the manhole, but it is usually desirable to have a few recesses, and if there are too many, the strength of the receiving frame 2 and the ability to support the lid will decrease. Therefore, you need to be careful.

In this invention, the lid receiving part 1 of the receiving frame 2 and the outer peripheral edge of the lid 3 inclined at the same angle fit together, and the lid 3 is integrated with the receiving frame 2 in a close contact state, so that no looseness occurs and , a biting force is generated, and the reaction force from the receiving frame 2 surrounds the lid 3 to resist the load force, resulting in the strength of the lid 3 being increased by the receiving frame 2. Since the plurality of recesses 4 are provided, the receiving frame 2 can easily expand in the horizontal direction even under the same load, and this gives some elasticity to the receiving frame 2, making it difficult to fit and bite the lid 3. Furthermore, if the burl 9 is inserted into the recessed part 4 and the space of the burl hole 10 and a load is manually applied to the burl 9, the inclination angle of the burl 9 with the horizontal plane can be reduced compared to the case where the burl 9 is inserted only into the conventional burl hole 10. is approximately 45 degrees or more, the crowbar 9 can be brought closer to the horizontal at an angle of about 35 degrees, and the vertical force exerted on the lid 3 by the crowbar 9 is increased. 3 can be opened easily.

As described above, according to the present invention, by forming the receiving frame 2 and the lid 3 with steep slopes, and by forming the plurality of recesses 4 in the receiving frame 2, some elasticity is imparted to the receiving frame 2, and the lid Since the biting force between the lid and the receiving frame is further increased, backlash is eliminated, and the advantage of the steeply sloped receiving structure of substantially increasing the strength of the lid is increased.

Moreover, when opening the lid, there is an effect of making it easier to open the lid and lift the lid using the crowbar 9 despite the strong biting.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the manhole cover structure of the present invention, Fig. 2 is a vertical sectional view taken along the line I-I in Fig. 1, and Fig. 3 is a plan view showing the manhole cover structure of the present invention.
It is a vertical cross-sectional view taken along the line -■. 1... Lid holder, 2... Receiving frame, 3...
... Lid, 4... Recessed part.

Claims (1)

[Scope of utility model registration request] A lid 3 whose outer periphery is inclined at the same angle of inclination as that of the lid holder is attached to a receiving frame 2 having an inclined lid holder 1 so as to be able to fit therein, and a plurality of crow holes 10 are formed in the outer periphery of the lid 3. The manhole cover structure is formed by forming a recessed part 4 on the inner peripheral part of the cover receiving part 1 of the receiving frame 2 at a position facing the burl hole.