IMPROVEMENTS IN THE CONSTRUCTION OF TRAPS FOR SINKS OTHER CONDUITS FOR WATER AND OTHER FLUIDS
Year: 1874

page_text: LETTERS PATENT to Henry Thomas Davis, of St. Donatts Road,
Lewisham Road, New Cross, in the County of Surry, for the
Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF TRAPS FOR SINKS,
Sealed the 27th April 1875, and dated the 22nd December 1874.
PROVISIONAL SPECIFICATION left by the said Henry Thomas Davis
at the Office of the Commissioners of Patents, with his Petition,
on the 22nd December 1874.
I, HENRY THOMAS DAVIS, of St. Donatts Road, Lewisham Road, New
Cross, in the County of Surry, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF TRAPS FOR SINKS,
DRAINS, AND OTHER CONDUITS FOR WATER AND OTHER FLUIDS," to be as
follows:-
My Invention relates to apparatus for preventing the escape of
noxious gases and poisonous vapours passing from sewers or drains into
houses through the ordinary channels, or drains communicating with the
said sowers or drains. It is chiefly designed for being placed in the sink of

page_text: a kitchen, but is applicable to any place where it may be desirable to
prevent the escape of foul air.
-
My improved apparatus is constructed as follows:-To a cylinder of
iron or other metal I attach a short length of pipe, which pipe rises from
the inner bottom, and on the top of the said cylinder I affix two circular
plates of brass or other metal. These plates are perforated at regular
distances, having blank spaces between the perforations. The top plate
is made to revolve within a rim fitted round the bottom plate. I affix
to the lower side of the bottom plate, in the centre, a short tube of metal,
and from the centre of the lower side of the top plate I also affix a short
length of metal tube in which I enclose a tube of brass or other metal.
In the latter tube I cut two spiral grooves or slots corresponding with
which are two studs or pins fixed in the outer tube; on the lower
end of the inner tube I attach another length of tube of suitable metal,
which tube is enclosed by the tube affixed to the lower perforated plate.
The inner lower tube has spiral grooves or slots corresponding with studs
or pins fixed in the outer tube; these grooves or slots running in a
contrary direction to the grooves or slots in the upper tube, so that when by
the turned action of the top plate the upper tube is revolved to the extent
of the groove or slot in it, the action is continued to the lower tube and
it is drawn up or depressed as required. To the lower end of the bottom
tube I affix a round plate or stop of suitable metal covered with leather
or other suitable material. I adjust the distance between the end of the
lower tube and the top of the pipe rising from the bottom of the cylinder,
so that when the former is depressed the plate or stop is pressed closely
down on the top of the latter and the top plate, by which that action is
controlled, covers the holes of the lower perforated plate. I attach to
the outside of the tube affixed to the lower perforated plate a circular
piece of metal of a bell shape, the lower edge of which is below the top
edge of the pipe rising from the bottom of the cylinder.
I cause the tube affixed to the upper perforated plate to rise a short
distance above the surface of the plate, on which I fix a circular brass
plate; beneath this plate and enclosed in the tube I fix a spring for
securing the return of the top plate to the required distance for covering
the perforations of the lower plate. The top plate is turned back by the
hand when required for the purpose of allowing water or other liquid to
pass through the trap into the drain.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Thomas Davis in the Great Seal Patent
Office on the 22nd June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
THOMAS, DAVIS, of St. Donatts Road, Lewisham Road, New Cross, in the
County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of December, in the
year of our Lord. One thousand eight hundred and seventy-four, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Henry Thomas Davis, Her
special licence that I, the said Henry Thomas Davis, my executors,
administrators, and assigns, or such others as I, the said Henry
Thomas Davis, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF TRAPS FOR SINKS,
DRAINS, AND OTHER CONDUITS FOR WATER AND OTHER FLUIDS," upon the
condition (amongst others) that I, the said Henry Thomas Davis, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Henry Thomas Davis, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the figures.
and letters on the accompanying Sheet of Drawings, that is to say :-
My Invention relates to apparatus for preventing the escape of
noxious gases and poisonous vapours passing from sewers or drains into
houses through the ordinary channels or drains communicating with the
said sewers or drains. It is chiefly designed for being placed in the sink

page_text: of a kitchen, but is applicable to any place where it may be desirable to
prevent the escape of foul air.
My improved apparatus is constructed as follows:-To'a cup-shaped
cylinder of iron or other metal I attach a short length of pipe, which
pipe passes through the bottom of the cylinder, one end of the said pipe
rising a short distance above the inner bottom of the cylinder, and the
other end communicating with the ordinary pipe of a sink. On the top
of the cylinder I affix two circular plates of brass or other metal, and
said plates are perforated at regular distances and have blank or solid
spaces between the perforations. The top plate is constructed to revolve
within a rim fitted round the outer edge of the bottom plate, the latter
plate being closely fitted to the inner side of the top of the cylinder.
I affix in the centre at the lower side of the bottom plate a short tube of
metal, inside of which near the bottom edge I affix two short pins or
studs placed opposite each other. Inside this tube is another tube
having curved slots or grooves cut therein to correspond with the pins
or studs of the outer tube, and on the lower end of the inner tube I affix
a circular plate of brass or other metal covered with leather, gutta
percha, or other suitable material, which when pressed down by an
action to be herein-after described covers closely the top of the pipe
rising from the bottom of the cylinder, and inside of the inner tube I fix
another tube having curved slots or grooves running in a contrary
direction to the curves in the outer tube. On the centre of the lower side of
the top perforated plate I attach a tube of metal in which I fix two studs
or pins, said studs or pins working in the curved grooves or slots of the
tube fixed within the inner tube, these grooves or slots being curved in a
contrary direction to those in the tube in connection with the bottom
plate. By the turning action of the top plate the upper tube is revolved
to the extent of the grooves or slots in it; the action is then continued
on the tube on which the covered plate is affixed, and it is drawn up or
depressed as required. I adjust the distance between the end of the
lower tube and the top of the pipe, rising from the bottom of the
cylinder, so that when the former is depressed the covered plate is pressed
closely down on the top of the latter and the blank spaces of the top
perforated plate cover the holes of the lower plate, thus offering a further
security from the escape of foul air.
I cause the tube affixed to the upper perforated plate to rise a short

page_text: beneath this cover I enclose a spring. When it is required for water or
other liquid to pass through the trap, the top perforated plate is turned
back by hand, so that the holes in the lower plate are exposed, and
consequently the stop or plate on the lower tube is drawn up; but upon
the hand being withdrawn the spring causes the top plate to revolve so
as to cover the perforations in the lower plate, and the plate or stop is
pressed tightly down on the top of the pipe in the cylinder. I attach to
the outside of the tube affixed to the lower perforated plate a circular
piece of metal of a bell shape, the lower edge of which is below the top
edge of the pipe rising from the bottom of the cylinder.
In the accompanying Drawings Fig. 1 is a sectional view of the
apparatus; Fig. 2, a plan of the perforated plates; and Fig. 3, a sectional
view of a modification of the apparatus.
a is a cup-shaped cylinder, and b is the pipe passing through the
bottom thereof, and communicating with the ordinary pipe of a sink
at C. On the top of the cylinder a I affix two circular plates d, e, said
plates being perforated at regular distances and having blank or solid
spaces between them, so that the perforations of lower plate may
correspond with the perforations of the upper plate or with the blanks,
'as shown in dotted lines Fig. 2. The top plate d is constructed to
revolve within the rim on the bottom plate e, said plate e being closely
fitted to the inner side of the top of the cylinder a. Concentrically with
the cylinder and affixed to the bottom plate e is a short tube g carrying
two studs h. Inside the tube is an inner tube i having curved slots or
grooves k cut therein to correspond with the pins or studs of the outer
tube g, and on the lower end of the tubo i is a metal plate covered
with leather, gutta percha, or other suitable material, and when the said
plate is pressed down by the action of the spring m it closely covers
the top of the pipe b. Inside of the tube i is another tube n having
thereon curved slots or grooves o running in a contrary direction to the
curved grooves k. To the top perforated plate d is attached a tube p
carrying studs or pins which work in the grooves o of the tube n.
.
The normal condition of the apparatus is with the perforations in the
plates d and e closed, as represented in Fig. 2, and with the plate
pressed closely down by the spring m on the top of the pipe b so as to
present a double security against the escape of foul air, and a bell-
shaped metal piece q is provided on the tube g, the lower edge of which

page_text: is below the top edge of the pipe b. The spring m is secured to a centre
pin in the cap r, and by a pin passed through a slot in tube p is secured
to the stationary tube g. To open the trap the top plate d is turned by
the cap r, and the grooves o being curved in a contrary direction to the
grooves k, when by the turned action of the top plate d and cap r the
tube is revolved to the extent of the grooves or slots in it, the action is
then continued on the tube i, and it is drawn up or lowered with the
plate as required.
г
In the modification shown in Fig. 3, the tube i is of increased
thickness, and the grooves k and o are respectively formed on the outside
and inside thereof, the tube n being dispensed with and the tube p and
its studs working within the tube i and in the grooves o; in all other
respects the parts and the action thereof are the same, as shown in Fig. 1,
and set forth in the foregoing description as will be well understood.
Having now described the nature and particulars of my said Inven- 1
tion I claim, the improvements in the construction of traps for sinks,
drains, and other conduits for water and other fluids, substantially as
herein set forth and shewn on the Drawings.
In witness whereof, I, the said Henry Thomas Davis, have here-
unto set my hand and seal, this Twenty-seventh day of May, in 2
the year of our Lord One thousand eight hundred and seventy-
five.