IMPROVEMENTS IN PUMPS FOR SUPPLYING AIR TO SUBMARINE DIVERS
Year: 1871

page_text: LETTERS PATENT to Thomas Truscott, of Liverpool, in the County of
Lancaster, Submarine Diver, for the Invention of "IMPROVEMENTS IN
PUMPS FOR SUPPLYING AIR TO SUBMARINE DIVERS."
Sealed the 20th October 1871, and dated the 2nd May 1871.
PROVISIONAL SPECIFICATION left by the said Thomas Truscott at
the Office of the Commissioners of Patents, with his Petition, on
the 2nd May 1871.
I, THOMAS TRUSCOTT, of Liverpool, in the County of Lancaster,
Submarine Diver, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PUMPS FOR SUPPLYING AIR TO SUBMARINE DIVERS," to be
as follows:-
The object of my Invention for "Improvements in Pumps for Sup-
plying Air to Submarine Divers" is to construct pumps in such a
manner that the air supplied shall not be impregnated or tainted by the

page_text: oil used for lubricating; also to construct the said pumps in such a
manner that the valves may be got at for the purpose of cleaning more
readily.
Air pumps constructed according to this Invention are double-acting,
and consist of a cylinder open at top and bottom. The bottom of the
cylinder bolts on to a base plate, which carries a suction valve to admit
the air into the bottom of the cylinder. This valve may be an ordinary
brass lift or other suitable valve. The cover of the cylinder also carries
a similar valve opening downwards to admit air to the top of the
cylinder. The piston or plunger is formed of a double leather cup.
The rod passes through a stuffing box in the cover in the ordinary
manner. The cover is also supplied with a suitable cock for lubricating.
The delivery ports or passages are respectively at the top and bottom of
the cylinder. The top delivery port has a straight branch with a suitable
flange and a vulcanite india-rubber washer valve attached to suitable
scat. The bottom delivery port has an elbow branch rising upwards;
it is also fitted with a flange and a similar valve to the top port. The
top and bottom delivery branches are connected by a T pipe fitted with
flanges, which are attached to the flanges of the ports with suitable
screwed couplings. This pipe has a main delivery in its centre, from
which is led the air tube to the divers; or in the case where two pumps
are used a suitable connecting pipe is coupled on to the pipe of each
pump and the pipes to the divers lead from it. In the centre of this
connecting pipe a stop-cock may be fitted, so as to work each cylinder
separately in the case where it is required to supply air to two divers.
The base plate which carries the cylinders or pumps is fitted into the
usual wooden box, dovetailed into the timber in such a manner that it
can be easily removed for the purpose of getting at the bottom valve for
cleaning.
The action of the pump is thus :-In the down stroke the air is drawn
in through the valve in the cover; on the up stroke it is discharged
through the top delivery port and valve; also air is drawn in through
the valve in the base plate, and upon repeating the down stroke is
discharged through the elbow delivery port at the bottom of the cylinder.
Any oil that may have collected from lubricating lies at the bottom of
the cylinder, and the air, instead of being forced through and impreg-
nated with it, passes upwards through the elbow delivery pipe, thus

page_text: allowing the air to be supplied pure and free of taint to the diver. The
valves being in the cover and base plate are easily got at for the purpose
of cleaning and removing dirt.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Truscott in the Great Seal Patent Office
on the 1st November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
TRUSCOTT, of Liverpool, in the County of Lancaster, Submarine Diver,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of May, in the year of our
Lord One thousand eight hundred and seventy-one, in the thirty-fourth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Thomas Truscott, Her special licence that I, the
said Thomas Truscott, my executors, administrators, and assigns, or such
others as I, the said Thomas Truscott, 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 Islo
of Man, an Invention for "IMPROVEMENTS IN PUMPS FOR SUPPLYING AIR TO
SUBMARINE DIVERS," upon the condition (amongst others) that I, the
said Thomas Truscott, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 Thomas Truscott, 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 :-
The object of my Invention for improvements in pumps for supplying
air to submarine divers is to construct pumps in such a manner that the

page_text: air supplied shall not be impregnated or tainted by the oil used for
lubricating, also to construct the said pumps in such a manner that the
valves may be got at for the purpose of cleaning more readily.
Air pumps constructed according to this Invention are double acting,
and consist of a cylinder open at top and bottom. The bottom of the
cylinder bolts on to a base plate, which carries a suction valve to admit
the air into the bottom of the cylinder. This valve may be an ordinary
brass lift or other suitable valve. The cover of the cylinder also carries
a similar valve opening downwards to admit air to the top of the cylinder.
The piston or plunger is formed of a double leather cup. The rod passes
through a stuffing box in the cover in the ordinary manner.
The cover
is also supplied with a suitable cock for lubricating. The delivery ports
or passages are respectively at the top and bottom of the cylinder. The
top delivery port has a straight branch with a suitable flange and a
vulcanite india-rubber washer valve attached to suitable scat. The
bottom delivery port has an elbow branch rising upwards; it is also
fitted with a flange and a similar valve to the top part. The top and
bottom delivery branches are connected by a T pipe fitted with flanges,
which are attached to the flanges of the ports with suitable screwed
couplings. This pipe has a main delivery in its centre from which is led
the air tube to the divers, or in the case where two pumps are used a
suitable connecting pipe is coupled on to the pipe of each pump and the
pipes to the divers lead from it. In the centre of this connecting pipe a
stop-cock may be fitted so as to work each cylinder separately in the
case where it is required to supply air to two divers. The base plate
which carries the cylinders or pumps is fitted into the usual wooden box
dovetailed into the timber in such a manner that it can be easily
removed for the purpose of getting at the bottom valve for cleaning.
The beforegoing being the nature and object of my Invention, I will
now proceed to describe more in detail the manner in which the same is
to be or may be performed or carried out into practical effect, and in
order that the same may be more clearly and readily understood I have
hereunto attached three Sheets of Drawings illustrative thereof, and
have marked them with figures and letters of reference corresponding
with those in the following explanation. Like letters and figures are
used to denote similar parts.
Figure 1 (Sheet 1) represents a side elevation of an air pump according

page_text: front elevation of the same; Figure 3 (Sheet 3) is a plan of the same;
Figure 4 (Sheet 3) is a plan of the under side of bed plate with valve
seats; Figure 5 (Sheet 3) is a side view of same. The beforegoing
Figures are all drawn half size. Figures 6, 7, and 8 (Sheet 2) represent
full size views of suction valve on cover and guard and valve seat.
It will be seen upon reference that the pump consists of a cylinder A
open at top B and bottom C. The bottom bolts on to a base plate D,
which carries a suction valve E to admit the air into the bottom of the
cylinder. This valve may be an ordinary lift valve as shown, or any
other suitable valve. The top of the cylinder is fitted with a cover F,
which is bolted to the cylinder and carries a suction valve G (Figure 2,
Shoot 2,) shown full size at Figures 6, 7, and 8 (Sheet 2). This valve
opens downwards to admit the air into the top of the cylinder. The
piston or plunger H is formed of a double leather cup, the rod I working
through a stuffing box K in the ordinary manner. The cover is also
supplied with a suitable cock for lubricating. The delivery ports or
passages are respectively at the top and bottom of the cylinder, as shown
at Land L. The delivery ports are formed with elbow branches rising
upwards and fitted with a flange and carrying a vulcanite india-rubber
washer valve M and M' attached to suitable seat. The top and bottom
delivery branches are connected by a T pipe N fitted with flanges, which
are attached to the flanges of the ports in a suitable manner, as shown
at N¹ and N³. This pipe has a main delivery O from which is led the
air tube to the divers. In the case where two pumps are used a suitable
connecting pipe P is fitted on to the pipe of each pump and the pipes to
the diver or divers led from it. In the centre of this connecting pipe,
say at P, Figure 3 (Sheet 3), a suitable stop-cock may be fitted so as to
work each cylinder separately when it is required to supply air to two
divers. The base plate D which carries the cylinders or pump is fitted
with the usual frame and suitable gearing and fitted into the usual
wooden box and wedged there in such a manner that it can be easily
removed for the purpose of getting at the bottom valves E for cleaning.
The action of the pump is as follows:-In the down stroke the air is
drawn through the valves G in the cover F, and on the upstroke is
discharged through the top delivery port L and valve M. Simultaneously
with the discharge air is drawn through the valve E in the base plate
into the bottom of the cylinder, and upon repeating the downstroke is
discharged through the delivery port L' and the valve M¹ at the bottom.

page_text: Any oil that may have collected from lubricating the cylinder lies at the
bottom of the cylinder, and the air instead of being forced through the
delivery ports impregnated with oil passes away pure and free from
taint, the oil lying at the bottom of the cylinder; also through the
particular construction and base plate of the pump the suction valves
can be easily got at for the purpose cleaning and removing dirt.
Having now fully described and ascertained the nature and object
of this my Invention, and the manner in which the same is to be
or may be performed or carried out into practical effect, I would have it
understood that I do not limit myself to the exact dimensions and
relative proportions of the different parts of the arrangement as shown,
as it will be clearly seen that the same may be considerably varied
without departing from my Invention; but what I claim as secured to
me by Letters Patent as aforesaid is,―
Firstly. The construction of an air pump for supplying air to sub-1
marine divers, substantially in the manner and for the purposes hercin-
before described and set forth.
Secondly. The construction of an air pump with the delivery ports,
valves, and passages formed in such a manner that the lubricating
medium used will lay at the bottom of the cylinder instead of being
forced with the air through the ports, substantially in the manner as
herein before described, set forth, and illustrated.
In witness whereof, I, the said Thomas Truscott, have hereunto
set my hand and seal, this Thirtieth day of October, in the year
of our Lord One thousand eight hundred and seventy-one.
Witness,
FREDERICK J. CHEESBROUGH,
of 15, Water Street,
THOMAS (L.s.) TRUSCOTT.
Liverpool.