Improvements connected with Man-hole Frames and their Covers.
Year: 1893

page_text: ate of Application, 2nd Nov., 1893-Accepted, 2nd Dec., 1893
COMPLETE SPECIFICATION.
Improvements connected with Man-hole Frames and their Covers.
I, WILLIAM WATSON, of Broad Street, Bloomsbury, London, Manager, do
hereby declare the nature of this invention and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement :-
This invention relates to a novel construction or arrangement of air tight man-
hole covers, inspection covers and their frames for sewers, drains, and other places
where such are required.
For the purpose of my invention, I mould or cast the under side of the cover
with a depending rib or feather near the edges of the four sides, but at angles
therefrom at the corners, so as to be clear of the bolt holes.
The groove or recess in the frame is similarly shaped or formed for the reception
of the rib or feather of the cover in addition to the usual grease, sand, or other
material to seal the joint. The bolt holes of the frame are likewise clear of
groove or recess at the corners, and are in projections thereof, said projections
being above the base for the insertion of nuts into which the bolts can be screwed,
the chambers or slots in which the nuts are lodged being closed in with cement for
fixing the nuts in position when the nuts are tested for localising them.
The invention will be more particularly understood by the annexed drawings in
which
Figure 1 shows a part sectional plan of the cover and frame.
Figure 2 a section through the line a, b, of Figure 1, and
Figure 3 a section on the line c, d, of same figure.
A is the cover, B the rib or feather on the under portion near the sides C, C,
and D, D, are the angle ribs or feathers near the corners E, E, and forming a
continuation of the feather B. The corners E, E, of the frame are above the
base F, and chambers G thus arranged receive nuts H, which when gauged to the
bolt holes in the corners E, E, can be fixed by cement, or as desired. The bolts I
are let through from outside of cover A, the surface of which is scored, striated,
or otherwise of a rough character to prevent persons slipping thereon.
The cover I prefer is of the drop form (not hinged), so that it can be bodily
lifted, or dropped into place by the hand holds J, J.
The groove or recess K at the sides is continued at the angles L, L, around the
frame and can be charged with grease, sand, or other sealing body to prevent
escape of sewage, or other gas, bad smells, or obnoxious vapours, even should the
bolts I, I, be loose, or be removed, the seal being independent of all joints, key
holes, or passages found in other manhole covers, besides which my frames do not
interfere with the passing of workmen up or down the manhole; or the like, because
the corners are the least occupied during such passing.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The construction of manhole frames with angled corner grooves L, L, and
the cover with ribs D, D, as part of side grooves K, K, and side ribs B, B, as
described with reference to the annexed drawings for the purposes set forth.
2. Constructing manhole frames with recesses G, G, between the upper part C
and base F for nuts H, H, substantially as and for the purposes set forth.
3. Constructing manhole frames and covers in the manner set forth with the
"seal" independent of all joint and like openings, foldings, or crevices, and with

page_text: separated bolt holes, under which the nuts can be lodged and fixed, as described
and substantially as shown in the annexed drawings.
Dated this 2nd day of November 1893.
H: GARDNER,
Patent Agent, 166, Fleet Street, London,
Agent for the said William Watson.