Improvements in Covers or Means for Closing Man-holes of Drains or Sewer Connections and the like.
Year: 1892

page_text: Date of Application, 7th Apr., 1892
Complete Specification Left, 9th Jan., 1893-Accepted, 18th Feb.,
1893
PROVISIONAL SPECIFICATION.
Improvements in Covers or Means for Closing Man-holes of Drains
or Sewer Connections and the like.
I, SAMUEL STEVENS HELLYER of 21 Newcastle Street, Strand in the City
of London, Engineer do hereby declare the nature of this invention to be as
follows:-
My invention has for its object to provide a cover which is gas tight and one in
which the proper tightness can be readily ascertained. It is especially intended
for use in closing man-holes in connection with drains or leading to connections
between house drains and sewers or cess pools but it is also applicable to other
analogous purposes. According to my invention I provide two covers the space
between the covers being capable of being filled with liquid and constituting an
additional liquid seal. I make the frame or rim against which the covers bear
when in place with a projecting flange or broad web which is built into the sides of
the man-hole and is preferably formed with ribs, grooves or recesses for making a
secure joint by mortar or cement past which gas cannot escape. This frame has
around its inner edge a trough for containing liquid and outward of this a bearing
surface upon
which india rubber or other packing or yielding material is placed.
A cover is placed over the opening formed by the frame the said cover bearing
upon the india rubber or like material and having a depending lip which enters the
aforesaid trough in the frame. By means of screws and nuts or other fastenings
the cover can be forced down into close contact with the india rubber or like
material so as to form a tight joint. The liquid seal and bearing surface for the
india rubber or the like are surrounded by a recess in the frame the sides of which
are carried up to such an extent that the said recess will contain liquid which will
cover the inner cover herein before described when in place, as any leak will allow
this liquid to run therethrough a leak will be at once detected by the lowering in
level of the liquid. When the inner cover has been closed gas tightly so that the
liquid is retained above it the aforesaid outer cover is placed over it the said cover
having a lip which enters the liquid and forms the aforesaid additional liquid seal.
This outer cover may be of light material if the device is situated below the
ground level for instance in the man-hole beneath a surface place but if it be on
the ground level or in such situation as to require strength it can be made of
sufficient thickness to give it the requisite strength. When the cover is beneath
the ground level I prefer to make the opening in the frame in such a position that
there will be afforded on the said frame sufficient room for a man to stand thereon
whilst he is clearing the pipes or connections.
Dated this 7th day of April 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Covers or Means for Closing Man-holes of Drains
or Sewer Connections and the like.
I SAMUEL STEVENS HELLYER of 21 Newcastle Street Strand in the County
of 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 :—
My invention has for its object to provide a cover or device which cover or

page_text: device effects a gas tight closure & enables any leakage thereof to be readily
ascertained. It is especially intended for use in closing man-holes in connection
with drains or leading to connections between house drains and sewers or cesspools,
but it is also applicable to other analogous purposes.
I will describe my invention with reference to the accompanying drawing
wherein
Figure is a transverse section of means for closing man-holes of drains or
sewer connections or the like constructed according to my invention and Figure 2
is a plan with part broken away.
According to my invention in connection with the frame or plate C in which is
the man-hole c to be closed I provide two covers A and B the space between them
being capable of holding liquid and constituting an additional liquid seal. I make
the said frame or plate with a projecting flange or broad web C2 which is built
into the sides of the man hole and is preferably formed with ribs, grooves or
recesses for making a secure joint in the said sides by mortar or cement past or
around which gas from the sewer or the like cannot escape. This frame or plate C
has around the inner edge of the man-hole therein a channel or trough D for con-
taining liquid. Outward of this channel or trough at d is a bearing surface upon
which india rubber or other packing or yielding material is placed as shewn at e.
The cover A is placed over the opening c² in the frame or plate C the said cover A
bearing upon the india-rubber or like material e and having a depending lip a which
enters the aforesaid channel or trough D in the frame or plate C. By means of
suitable fastenings for instance screw bolts or clips and nuts as at f the cover A
can be forced down into contact with the india rubber or like material e so as to
form a gas and water tight joint. The liquid seal and bearing surface for the india
rubber, or the like, are surrounded by a recess c in the frame or plate C the sides
of which recess are carried up to such an extent that the said recess c will contain
liquid which will be above the joint of the inner cover A when in place. As any
leakage will allow this liquid to run therethrough a leak will be at once detected
by the lowering of the level of the liquid. When the inner cover A has been
closed tightly so that the liquid is retained above its joint the outer cover B can be
placed over it the said cover B having a lip which enters the liquid. This outer
cover may be of light material especially if the device is situated below the ground
level, for instance in the man-hole beneath a surface plate, but if it be on the
ground level or in such situation as to require strength the said outer cover can be
made of sufficient thickness to give it the requisite strength.
When the cover is beneath the ground level I prefer to make the opening in the
frame or plate C in such a position that there will be afforded, on the said frame or
plate, sufficient room (at a) for a man to stand thereon whilst he is opening or closing
the cover or cleansing the drains.
In Figure 1 I have shewn the cover B as having a rim 6' which rests on the
frame or plate C. It may however be made without this rim as shewn in Figure 3.
If desired the cover B may be dispensed with.
The man-hole and cover or covers may be circular or elliptical or of any other
suitable shape.
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. For closing man-holes of drains, or sewer connections, or the like, the com-
bination of a frame, or plate, having in it the man-hole, or opening, to be closed
and surrounding this a trough or channel and seating and packing thereon and a
cover such as A provided with a lip to enter the said trough or channel and means
for forcing the cover onto the packing and means whereby liquid can be retained
above the joint of the said cover substantially as and for the purposes hereinbefore
described.

page_text: 2. A device for closing man holes of drains or sewer connections or the like
arranged substantially as hereinbefore described and shewn in the accompanying
drawing.
Dated this 0th day of Lanna 1902
J. H. JOHNSON & Co.,
Agents.