Improvements in Ventilating Manhole and Lamphole Covers for Sewers.
Year: 1895

page_text: Date of Application, 15th Feb., 1895
Complete Specification Left. 15th Nov., 1895-Accepted, 1st Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in Ventilating Manhole and Lamphole Covers for
Sewers.
I RICHARD GEORGE HANSFORD WORTH of 42 George Street, Plymouth, in
the County of Devon, Civil Engineer, do hereby declare the nature of this invention
to be as follows:-
A manhole or lamphole cover in metal with a metal framework into which it fits
or is hinged, in the cover certain openings or apertures are left through which the
sewer may be placed in connection with the outer air; beneath these apertures is
placed a moveable tray, box or receptacle which collects and intercepts materials
or matter falling or finding its way through the ventilation apertures in the cover;
the invention consists in the manner and method in which this last mentioned tray
or receptacle is made to control the ventilation of the sewer.
This moveable tray
may be placed in a variety of positions and by varying its position the apertures in
the cover may be closed or cut off from connection with the sewer, or the passage
of air or gases, from or into the sewer may be regulated.
This I accomplish in the following manners :-
On the lower inside edge of the frame of the cover or at such position on the
frame as may be convenient I cast or attach a rim, or projection, or series of
projections or I make a socket on or in which the moveable tray or receptacle may
rest.
The tray which may be either oblong, square or circular in plan has one end
or side or portion of its circumference higher than the corresponding end or side
or portion of the circumference. When the cover is not ventilating the sewer, the
tray rests on the rim cast on the frame in such manner as to preclude the passage
of air or gas around two or three sides or portions of the circumference; while the
higher end, sides, or portion of the circumference of the tray makes contact with
the lower side of the cover in such manner as to preclude the passage of air or of gas.
If it be desired to cause the cover to act as a ventilator, the tray or receptacle is
changed in position, end for end, or side for side, when the lower end, sides, or
portion of circumference, failing to make contact with the under side of the cover,
a space is left which admits the passage of air or gas.
This method can be modified by the employment of trays or receptacles square
or polygonal in plan, or of circular receptacles, the circumferences of which are
subdivided, the sides of the square or polygonal trays or the subdivisions of the
circular receptacles can be made of graduated heights or so as to admit of a series
of openings of varying dimensions in accordance with the various positions of the
receptacles, by this means the ventilation can be efficiently regulated.
In the case of circular receptacles the movemeut may be effected by means of a
key without opening the cover.
I also accomplish the same object by causing the receptacle or tray to slide upon
or in the rim or groove in or on the frame. Such receptacle or tray closing the
passage for air or gas by making contact with the under side of the cover and by
its contact with the frame; when moved in a horizontal plane the said receptacle
ceases to make contact with the underside of the cover, and may in part cease to
make contact with the frame; by moving the tray or receptacle through a greater
or less distance the area of ventilation aperture may be regulated. This method

page_text: may be applied also to circular trays or receptacles, in which a movement of
rotation may be used.
I further accomplish the same object, when using a tray or receptacle of any
shape whatever on plan, by making the sides or portions of the sides of such tray
or receptacle of such depth that when such tray or receptacle is reversed, & the
sides rest on the rim on the frame, on which at other times the botton or other
portion of such tray would rest, the bottom of such tray comes in contact with the
underside of the cover, closing the ventilation apertures.
Dated this Fourteenth day of February 1895.
Improvements in Ventilating Manhole and Lamphole Covers for
Sewers.
•
I RICHARD GEORGE HANSFORD WORTH of 42 George Street, Plymouth, in
the County of Devon, Civil 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 :-
Metal manhole or lamphole covers fitted or hinged into metal frames and having
slots or apertures, substantially as shewn on drawings accompanying this Specifi-
cation, through which the sewer may be placed in connection with the outer air;
beneath these apertures is placed a moveable tray or receptacle which collects and
intercepts materials or matter falling or finding way through the ventilation
apertures in the cover; the invention consists in the manner and method which
the last mentioned tray or receptacle is made to control the ventilation of the
sewer. This movable tray may be placed in a variety of positions, and by changing
its position the apertures in the cover may be closed, or cut off from communication
with the sewer, or the passage of air or gases from or into the sewer may be
regulated.
This I accomplish in the following manner
On the lower inside edge of the frame of the cover, or at such position on the
frame as may be convenient I cast or attach a rim, or projection, or series of
projections, or 1 make a socket, on or in which the movable tray or receptacle may
rest.
The tray,
which may be either oblong, square, or circular in plan has one end or
side or portion of its circumference higher than the corresponding end or side or
portion of circumference. When the cover is not ventilating the sewer, the tray
rests on the rim cast on the frame in such manner as to preclude the passage of air
or gas around two, or three sides or portion of circumference; while the higher end,
sides or portion of circumference of the tray makes contact with the lower side of
the cover in such manner as to preclude the passage of air or gas.
If it be desired to cause the cover to act as a ventilator, the tray or receptacle is
changed in position, end for end, or side for side, when the lower end, sides, or
portion of circumference of tray, failing to make contact with the underside of the
cover, a space is left which admits the passage of air or gas.
This method can be modified by the employment of trays or receptacles square
or polygonal in plan, or of circular receptacles, the circumferences of which are
subdivided, the sides of the square or polygonal receptacles, or the subdivisions of
the circular receptacles can be made of graduated heights so as to admit of a series
of openings of varying dimensions in accordance with the various positions of the
receptacles, by this means the ventilation can be efficiently regulated.
In the case of circular receptacles the requisite movement may be effected by
means of a key, without opening the cover.

page_text: I also accomplish the same object by causing the receptacle or tray to side upon
or in the rim or groove, in or on the frame. Such receptacle or tray closing the
passage for air or gas by making contact with the frame and with the under side of
the cover; when moved in a horizontal plane the said receptacle ceases to make
contact with the under side of the cover, and may in part cease to make contact
with the frame: by moving the tray or receptacle through a greater or less distance
the area of the ventilation aperture may be regulated. This method may be
applied to circular trays or receptacles in which a movement of rotation may be
used.
I further accomplish the same object, when using a tray or receptacle of any
shape whatever in plan, by making the sides or portions of the sides of such tray
or receptacle of such depth that when such tray or receptacle is reversed, and the
tray rests on other portions of its sides from those on which it rests before reversal,
or the sides rest on the rim of the frame, on which at other times the bottom or
other portion of such tray would rest, the bottom of the tray comes in contact
with the under side of the cover, closing the ventilation apertures.
Figures 1, 14, and 18 of the accompanying drawings show plan and sections of a
manhole or lamphole cover, made after the first of the herein mentioned methods.
Figure 1 shews a section of such cover when the ventilation aperture is closed.
The higher side of the square tray of which h, h¹, h³, h³ represent the respective
sides is shewn in contact with p, a portion of the lower surface of the cover, and is
elsewhere in contact with a rim cast on the frame of the manhole. Communication
between the space s, in direct communication with the sewer, and the ventilation
openings vis thereby closed.
Figure 1B is a section shewing the ventilation of the sewer by means of the
passage between the top of h³, one of the sides of the tray, and p. This is
accomplished by changing ends of the tray.
More ventilation may be obtained by bringing h³ under p, or less by bringing h¹
under p.
Figure 1 is a plan of the manhole.
Figures 2, 24 and 2B, are plans and sections of a manhole or lamphole in which
the regulation of the ventilation is accomplished by moving the tray t in a
horizontal plane. Figure 24 shews the ventilator closed with t in contact with p,
a portion of the under surface of the cover; and opened when t is slid into the
position t¹. Notches n are provided, into which a slight projection on the sliding
tray fits, thus securing this tray in position.
Figures 3, 34 and 3B shew a plan and two sections of a circular manhole or lamp-
bole cover in which the ventilation is cut off by reversing the tray or receptacle d,
so that in place of hanging from the projections m, which engage the rim r, it
hangs from the projections n. The projection n is made in such form as to act as
a spring and keep the bottom of the tray in close contact with the under side of
the cover. A handle is provided for lifting the receptacle when reversed.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is
1. The application and use in manholes and lampholes of a cover having slots in
a portion of same and a loose tray reversible from side to side or end to end, or
rotary, whereof one side or portion of circumference makes contact with the under
side of the cover thus closing connection between the sewer and the ventilation
slots;
and the other sides or portions of the circumference when brought into the
position, occupied by the first named when the ventilation is closed, do not meet
the under side of the cover but leave an interval through which the sewer com-
municates with the ventilation slots.
The regulation of such ventilation by varying the heights of the sides or portions
of the circumference of such tray, so that certain sides or portions of circumference

page_text: may leave a greater interval, and certain sides a less interval for the escape of gas
or air from the sewer.
2. The construction of a manhole or lamphole cover as shewn on Drawings 1, 1ª
and 1B.
3. The application and use in manhole and lamphole covers having slots in the
cover for purposes of ventilation of a sliding tray or receptacle, which when in one
position meets the sides of the frame, and the under side of the cover in such
manner as to prevent communication between the sewer and the ventilation slots,
but when slid or rotated into another position or other positions ceases to make
contact with the under side of the cover, and may cease to make contact with a
portion of the frame in which the cover is set, thereby opening the communication
between the sewer and the ventilation slots aforesaid.
The regulation of the amount or extent of ventilation by the degree of change
of position imparted to the cover.
4. The construction of manhole and lamphole covers as shewn on Drawings 2,
24, 2B.
5. The application and use in manhole and lamphole covers, having slots as
before described, of a reversible tray or receptacle which when reversed brings
the bottom of such tray or receptacle in contact with the under side of the cover
and thus prevents communication between the sewer and the ventilation slots
aforesaid.
6. The construction of manhole and lamphole covers as shewn on Drawings 3, 3ª
and 3B.
Dated this 13th day of November 1895.