Improvements in manhole and other covers used for sewerage works.
Year: 1898

page_text: I, FREDERIC GEORGE SISON HAM, of 13, Grosvenor Road, Westminster, Engineer,
do hereby declare the nature of this invention to be as follows:-
Improvements in manhole and other covers used for sewerage works. To the cover
in general use provided with ventilating openings I fit a dirt box preferably made
in sheet iron. This box is suspended from the frame of cover and is made to
fit on a flange on the frame so that no space is left around it through which
sewer air could pass. Carried through the bottom of the box is a vertical pipe
one end of which is extended to a point near the underside of the cover.
the underside of bottom of box fitting to a seating I form a check valve made
preferably of aluminium which I hinge on to the bottom of box by suitable
attachments having a lever and weight to balance it in position.
On
When this box is fitted under a sewer ventilating cover it will allow fresh
air to enter the sewer but it will also prevent sewer air escaping to the atmosphere
from the fact that the check valve will open only when the down draught is
sufficient to press open the valve fitted to the underside of the box.
I may vary the construction of the box described above by forming a hori-
zontal partition across the vertical pipe above referred to in which case I should
cut away portions of the pipe below the partition to allow air to pass. I may
also arrange a box to arrest dirt on the upper side of the horizontal partition.
The check valve or disc of aluminium referred to above may be dished to
strengthen it and the edges may be turned up to allow it to retain liquid. The
lever to which the check valve is connected is preferably made with a balanced
end to ensure the valve remaining normally on its seat and a jockey weight may
be added to allow of adjustment.
I form 3 or more legs on bottom side of box for protecting the valve
from injury.
In cases where it is desired to use a solid cover over the manhole or inter-
cepting trap in which this box is fitted I form an opening in the side of frame
of cover and connect up a pipe or shaft which pipe may be coupled up to a wall
box having ventilating openings on side to allow air to pass into the sewers
and at same time prevent any dirt stones sticks or other matter falling into the
sewer such stones and other matter being caught in the frame and prevented falling
into sewer by the vertical pipe before referred to.

page_text: FREDERIC GEORGE SISON HAM, 13, Grosvenor Road, Westminster, London,
Engineer, 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:—
Improvements in manhole and other covers used for sewerage works. To the cover
in general use provided with ventilating openings I fit a dirt box preferably made
in sheet iron. This box is suspended from the frame of cover and is made to
fit on a flange on the frame so that no space is left around it through which
sewer air could pass. Carried through the bottom of the box is a vertical pipe
one end of which is extended to a point near the underside of the cover. On
the underside of bottom of box fitting to a seating I form a check valve made
preferably of aluminium which I hinge on to the bottom of box by suitable
attachments having a lever and weight to balance it in position.
When this box is fitted under a sewer ventilating cover it will allow fresh
air to enter the sewer but it will also prevent sewer air escaping to the atmosphere
from the fact that the check valve will open only when the down draught is
sufficient to press open the valve fitted to the underside of the box:
I may
I may vary the construction of the box described above by forming a hori-
zontal partition across the vertical pipe above referred to in which case I should
pass.
cut away portions of the pipe below the partition to allow air to
also arrange a box to arrest dirt on the upper side of the horizontal partition.
The check valve or disc of aluminium referred to above may be dished to
strengthen it and the edges may be turned up to allow it to retain liquid. The
lever to which the check valve is connected is preferably made with a balanced
end to ensure the valve remaining normally on its seat and a jockey weight may
be added to allow of adjustment.
I form three or more legs on bottom side of box for protecting the valve
from injury.
In cases where it is desired to use a solid cover over the manhole or inter-
cepting trap in which this box is fitted I form an opening in the side of frame
of cover and connect up a pipe or shaft which pipe may be coupled up to a wall
box having ventilating openings on side to allow air to pass into the sewers
and at same time preventing any dirt stones sticks or other matter falling into sewer
such stones and other matter being caught in the frame and prevented falling
into sewer by the vertical pipe before referred to.
In the accompanying drawing the check valve or disc of aluminium is shown
at A fitted to bottom of box B provided with vertical pipe C.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1st. The dirt box for sewer cover fitted with balanced flap substantially as
described and shown.
2nd. The sewer ventilation and aeration cover substantially as described.
Dated this 21st day of November 1898.