JPH0317006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to manhole covers or other doorway covers. Although the invention has particular application to lids made of cast iron, it is not limited to lids made of cast iron.

Manhole covers are usually provided with a number of hook holes into which hooks or hook-like tools can be inserted and used to raise the cover from its frame either directly or by the action of a lever. There are limited British standards for hooks and hook holes for manhole covers, but these standards are often not suitable for manufacturers, and manufacturers often use hooks that only fit the covers they supply. It is not uncommon for this to be requested. For this reason, people who use a large amount of lids, such as public organizations and waterworks departments, have no choice but to prepare hooks of various shapes for each worker, and the workers can then pick the lids from among the hooks. I select and use hooks that match the type. However, in some cases, the worker's hook does not fit into the lid, and he is forced to insert an inappropriate tool, such as the end of a pickaxe, into the hook hole in the lid to lift the lid.

The present invention provides a hookhole shape for a manhole cover or similar entrance/exit cover that can be used with any of the numerous hooks currently in use and is suitable for use in operations. An employee can open the lid by picking up one of the many hooks. Not only that, but if the hook you are holding does not fit into the hook hole, you can use a pickaxe to lift the lid if necessary.

According to the present invention, at least one hook hole is provided in a manhole cover or a similar doorway cover, and a tool for lifting the cover is inserted into the hook hole, and the cover is pulled up by the action of a screw. a hookhole adapted to be lifted from the frame of the lid, the hookhole having a recess, the recess being provided in the upper surface of the lid, the recess having two parts of different depths;
Between the two parts there is a stepped part, a crossbar crossing the mouth of the recess, the position of the crossing being above and away from the stepped part.

It has been found that a suitably sized hookhole of the shape described above can cooperate with a number of different shapes of hooks currently in use to lift a lid provided with this hookhole.

The hookhole has many more specific features that increase the variety of hooks that can be used in the fishing hole. One of the features is that the crossbar can be shaved along its lower edge, such that this shaved part faces a part of the recess, preferably a shallower recess. Preferably, a portion of the lower edge of the crossbar portion remote from the shaved portion is smoothly curved.

Preferably, a portion of the crossbar portion projects into each of the recesses. When cutting the crossbar-like portion, it is preferable to cut only the portion substantially facing the recess.

The shallow portion of the recess may be narrower or shorter than the deep recess. The entrance of either or both of the recesses is specified as a hole, the dimension of this hole in one direction is narrower than the recess, and the opposite sides of the hole are partitioned off by flanges that partially overhang the recess. It can also be done. Preferably, each hole has straight parallel sides and rounded ends.

Preferred embodiments of the present invention will be described below with reference to the drawings.

1 and 2, hook holes 10 are integrally cast in each corner of a cast iron lid 11. In FIGS. This hookhole is arranged with the upper surface of the lid, which has two recesses 12, 13 of different depths, and between these two parts 12, 13 there is a step 14.

A crossbar-like portion 15 connects the mouth of the recess to the step portion 1.
4 and on both sides of this crosspiece 15 are holes 16, 17 which lead into said recesses 12, 13. Since both sides of the holes 16, 17 are parallel and rounded at the ends, and the width of the holes 16, 17 is narrower than the recess, two flanges 18 are provided on the inside, as best shown in FIG. 18 rests on said larger recess 13 and similar flanges are on either side of said smaller recess 12.

The crossbar-like portion 15 is round when viewed from above, and the lower side of the crossbar-like portion 15 is shaved, and the shaved portion 19 faces the smaller recess 12 and has a smooth curved surface. Part 20 of
faces the larger recess 13. Substantially all of the cut portion is within the smaller recess 12.

2 and 3 show a British Standard hook 21 having a cylindrical metal rod 22 with diametrically opposed square ears 23 at one end of the rod 22. Welded. The dimensions of this ear 23 are
The end of the metal rod supporting this ear 23 is the ear 23
and the ears extend in the axial direction of the hole. Next, the hook is 90° from the position shown in Figures 2 and 3.
turned, and in this position the ear 23 is attached to the flange 1.
8 so that the corner of the lid can be pulled up by pulling up the metal rod.

FIG. 4 shows a conventional hook-like lifting hook 24.
This hook 24 is connected to the holes 16 and 1 as shown in FIG.
7 and hooked on the underside of the crossbar-like portion 15. Preferably, the lifting hook is inserted into the smaller hole 16 as shown in FIG. 4, since after said insertion the lifting hook is inserted into the stepped portion 14 as shown This is because it will cause an interruption. After making this interruption, make the lifting hook take an angle that can lift the lid,
This angle is set so that the lid is lifted by the action of a lever rather than being lifted directly by the lifting hook.

FIG. 5 shows a bus-shaped hoisting hook 25 which has two substantially horizontal arms 26, 27 which are pivotally connected by bolts 28. Ru. The arms 26 and 27 are formed integrally with the rims 29 and 30, respectively. One rim 3 of the lifting hook
0 has a simple shape, whereas the other rim 29 forms a hook portion 31 at its tip.

Insert the rims 30 and 29 of the tip of the lifting hook into the holes 16 and 17, and then
6 and 27 upward to close the rims facing each other, and then pull up the lifting hook. The crosspiece 15 can then be inserted between the rims 29, 30 and the hook 31 and the lid can be pulled up in this way.

FIG. 6 shows a type of hook that has become known as a "Gloster" type hook. The hook has a bar 32 with a receptacle 33 at one end and a shoulder 34 at the other end. A hook portion 36 extends downward from the middle of the bar 32, and threaded eye bolts 37, 38 are attached to the bar 3.
Cross 2.

When using the lifting hook, the hook portion 36 is lowered through the larger hole 17 and engaged with the underside of the crossbar 15. Next, the eye bolt 37 is lowered while rotating with a screw until the plug 39 of the eye bolt 37 enters the smaller hole 16, and the flange 40 adjacent to the plug 39 is lowered.
is engaged with the upper surface of the lid while contacting either side of the hole 16. The eye bolt 37
is further lowered so that the shoulder portion 34 comes into contact with the surface of the lid, the hook portion 36 is upwardly engaged with the crossbar-shaped portion 15 by the action of a screw, and the eye bolt 37 is further lowered. to firmly fix the bar 32 to the lid.

The eyebolt 38 can be lowered until its end engages the frame, the engaging portion being that portion of the frame adjacent to the edge of the lid. The eyebolt applies an upward lever force to the hook so that the lid can be levered up.
An extension rod (not shown) is inserted into the insertion port 33 to strengthen the action of the screw.

FIG. 7 shows the situation when the lid is pulled up with a lifting hook of the type known as a "gachitsuku" hook. This pulling hook is made of a thick steel plate 41.
A handle 42 slanted to the side is welded. Said steel plate 41
When the bolt 43 is lowered so as to penetrate through the bolt 43, a hook portion 44 is formed at the end of the bolt 43. This hook part 4
4, properly orient the hook 44, lower the hook 44 through the smaller hole 16 into the narrow recess 12, and insert the hook 44 into the narrow recess 12.
The bolt 43 is rotated and held in this recess 12. The bolt 43 with the fixing nut 45
This rotation is performed above the steel plate 41 to prevent the bolt from being turned too much. In this way, the lid can be lifted by the handle 42.

In FIG. 8, the tips of the pickaxes 46 and 47 are shown in the hole
6 or 17, and the lid is lifted by the action of a screw. If the pickaxe head 46 is used, the pickaxe head 46 is inserted between the stepped portion 14 of the lid and one end of the hole 17; A pickaxe 47 is inserted between the bottom corner of the recess 12 and the crossbar 15.

[Brief explanation of the drawing]

Figure 1 is a plan view of the corner of the manhole cover where the hook hole is located, Figure 2 is a longitudinal sectional view of the hook hole into which the British Standard lifting hook is inserted, and Figure 3 is the line shown in Figure 2. 3-3; FIGS. 4 to 7 are cross-sectional views taken along line 3-3 in FIG. 2 when a recently used type of pulling hook is used in the hook hole;
FIG. 8 is a cross-sectional view taken along line 3--3 of FIG. 2 when using a pickaxe with a suitable hoisting hook. 10, 16, 17...Hook hole, 11...Lid, 1
2, 13... recessed portion, 14... stepped portion, 15...
... Crossbar-shaped part, 18 ... Flange, 19 ... Shaved part, 20 ... Part of curved surface, 21, 25 ...
...Hook hook, 22...Metal rod, 23...Ear, 26,
27...Arm, 28...Bolt, 29,30...
...Rim, 32...Bar, 33...Socket, 34...
...Shoulder part, 36...Hook part, 37, 38...Eye bolt, 39...Plug part, 40...Flange, 41
... Steel plate, 42 ... Handle, 43 ... Bolt, 44
... Hook part, 45 ... Fixing nut, 46, 47 ...
...Pickaxe.

Claims (1)

[Scope of Claims] 1. A manhole cover has a large number of hook holes, and the cover can be removed from its frame by inserting hooks or other tools into the hook holes, and the recess of the hook hole In the manhole cover provided on the upper surface, the recess has two portions 12 and 13 with different depths,
There is a stepped part 14 between these two parts,
A cover for a manhole or the like, characterized in that a crossbar-like section 15 traverses the recess opening, the opening being located above and remote from the step-like section. 2. The crossbar-like part 15 has a cut-out part 19 along one of its lower edges, which cut-out part faces a part 12 of the recess. Covers for manholes, etc. described in Scope 1. 3. A cover for a manhole or the like according to claim 2, wherein the scraped portion 19 faces the shallower recess 12. 4. The entire scraped portion 19 substantially forms the recess 12 facing the scraped portion.
The second claim characterized in that
Covers for manholes, etc. described in Section 3 or Section 3. 5. According to any one of claims 2 to 4, the lower edge of the crossbar-like portion 15 and the portion opposite to the shaved portion 19 is smoothly curved. Covers of manholes, etc. mentioned. 6. The crossbar-like portion 15 is connected to each part 12 of the recess,
A cover for a manhole or the like according to any one of claims 1 to 5, characterized in that the cover extends into the inside of the manhole. 7 The shallower recess 12 is the deeper recess 1
7. A cover for a manhole or the like according to any one of claims 1 to 6, which is narrower or shorter than 3. 8. The opening of at least one of said recesses 12, 13 is defined by a hole 16, 17, narrower than one dimension of said hole 16, 17, so that the opposite side of said hole has a flange 18. The first aspect of claim 1 is characterized in that the flange is partitioned by a flange, and a part of the flange protrudes above the recess.
A cover for a manhole, etc. according to any one of Items 7 to 7.