Year: 1887

page_text: Date of Application, 25th Jan., 1887
Complete Left, 25th Oct., 1887
Complete Accepted, 25th Jan., 1888
I, ALEXANDER CONACHER of Augusta in the County of Richmond and State of
Georgia in the United States of America, but at present of 51 Thames Street Windsor
in the County of Berks Gentleman, do hereby declare the nature of this invention to
be as follows:-
a
The air pump consists of two perpendicular pump barrels or columns resting on a
horizontal pipe or closed chamber. This latter has a crank shaft passing along its
"boss "
bored in the
centre longitudinally one end of shaft having a bearing in
interior of centre of one end of said pipe or chamber and the other end of shaft
passing out through the opposite end of pipe with bearing and stuffing box. The
boss and the stuffing-box may be in covers, screwed onto the end of the pipe or
chamber. This crank shaft has two cranks placed oppositely to each other each of
A piston is
which is directly below centre of one of the upright barrels named.
fitted to work in each of the upright barrels and these pistons are operated from their
respective cranks by connecting rods. The tops of the barrels are domed and in the
centre of the dome a circular metal plate is seated having the seats of the suction and
discharge valves of the pump.
The suction pipe leading to pump barrel is screwed into a recess bored into the
centre of the top side of this plate or otherwise united thereto. The suction valve is
made of a metal disc faced with rubber or leather and it seats on the centre of the
underneath side of the plate first named having its stem passing through this plate
and the stem extending upwards inside the suction pipe for a length exceeding the
length of the stroke of the pump. This valve seat is formed of a beading or pro-
jection on the underneath side of the valve seat plate making the seat of the valve
lower than the rest of the plate by " to ". The metal disc of suction valve is made
larger in diameter than the beading on which the valve seats and its outer edge is
cupped upwards to a sufficient height to ensure the recess thus formed holding the
rubber or leather facing and also to ensure that the top edge of this cup shall when
the valve is seated be above the level of the bottom of the beading which forms the
valve seat.
A number of holes are drilled round the centre hole through which the

page_text: valve stem passes (and inside the beading forming the seat) which form the inlet
from the suction pipe into the pump barrel. The valve stem named is made of pipe
closed at the top end but passing down through valve and valve plate and open at its
lower end.
The discharge valve consists of a disc of rubber or leather resting on top side of
plate first named with its centre cut out to let it pass over suction pipe and a number
of holes are drilled through the plate which form outlets from pump barrel and over
which the valve rests.
•
A domed cap is fitted to screw over the plate to make it seat tightly on top of
barrel or column. It has a hole in centre of top of dome to admit the suction pipe
passing down through it and an outlet at side for discharge pipe to be screwed into.
The bottom of this discharge outlet being slightly above the level of the seating of
discharge valve. The dischargo pipes from each barrel lead into a trap cylinder or
perpendicular pipe placed on top of horizontal pipe which connects the two pump
barrels below and connected therewith by a small pipe. This trap cylinder is open
at top.
The pump pistons are formed as to their upper side to fit the shape of the pump
barrels or columns and are of sufficient thickness to admit of a recess being made in
the centre of each on the top side to receive the bottom of suction valve at the end of
the upstroke while the rest of the face of piston fits close close up to the bottom of
discharge seat and dome at end of stroke.
In the centro of this recess in top of piston a small perpendicular rod is fixed the
upper end of which enters into the hollow stem of the suction valve before named,
room being left in the latter by a rubber or other ring or spring or springs being
affixed to the suction valve so as to clasp or hold the rod with any desired tension.
Each discharge valve has a metal washer or ring on top and held to its seat by a
spiral spring pressing between it and interior of cap. The suction valves are held up
to their seats by spiral springs round valve stem and the travel of the suction valves
is limited by stops on the hollow spindles which allow of said valves opening to a
sufficient extent when said stops strike on the top of the bearing in the top of the
caps. A small pipo is connected to the lower part of cach upright pump cylinder
slightly above top of piston when it is at its lowest point in the pump, the other end
of the pipe is inserted into the horizontal pipe forming base of columns or pump
barrels and near the bottom of column. The crank shaft is driven by hand or other
power in the usual way.
To operate the pump, a hydrocarbon oil having a boiling point of 450° to
600° Farenheit is poured into the pump until it fills the whole space up to the under-
sides of the pistons and fills part of the trap cylinder. The pump being operated a
very high vacuum is obtained as at each stroke of each piston when it passes below
the small pipe near the bottom of column a minute quantity of oil is passed in on top
of piston and towards end of the stroke this oil fills up, the space between top of piston
and interior of dome of column pressing every particle of air or vapour out through
the discharge valve and itself also passing out through this valve and thence into the
trap cylinder and thus "liquid sealing" the discharge valve. The suction valve is
mechanically opened at the beginning of the downward stroke of the piston by the
small rod which rises from centre of top of piston and passes up the interior of hollow
valve stem being clasped closely by the rubber or other spring in interior of the latter
thus pulling the suction valve open the proper distance. At the beginning of the
upward stroke of the piston the same rod pushes the valve to its seat (aided by the
spiral spring around its stem for that purpose), while the cup forming a raised rim
around the valve ensures the valve seat heing covered with oil and being "liquid
sealed "thus preventing any of the air or vapour drawn into the pump escaping
through the suction valve.
This pump differs from the one patented to Conacher & Williams on 2 November
1886 (Patent No. 14082) in the construction of the "barrels" or cylinders-the
simplicity of its form, its compactness, and relative cheapness, the almost entire
absence of joints liable to leak under high vacuum, and the novel construction of the

page_text: valves, their simplicity and effectiveness, and the method of opening the suction valves
and of liquid sealing the same also in the automatic discharge of small portion of oil
into the pump at each stroke to ensure complete discharge of all air or vapor at each
stroke. The oil beneath the pistons being exposed to the atmospheric pressure
through the top of trap cylinder being open ensures the pistons doing good work
even if they do not fit the interior of columns very closely. The piston is formed of
a pump leather fitted over a plate which is underneath it and having a metal "piston
head to fit the shape of top of barrel or column as before named resting on top of
the leather the first named plate is screwed up to this piston head or block the leather
being cut away for the purpose in the centre. The "pipe" forming the base of the
pump is cast in two pieces each piece forming the base of a column attached to it by
Hanges. These pieces are enlarged in their diameter where they enclose the cranks
so as to allow of a sufficient length of stroke and they are connected together by a
short piece of pipe screwed into them this pipe being of sufficient size to let the crank
shaft pass through it. This form materially lessens the cost of manufacture and
makes the pump much lighter. A small gutter or depression is left in bottom of base
of columns with a
<< boss 29
to attach a pipe and cock to empty the pump. The
columns are cast in one piece with a seat turned on top to receive the plate forming
valves and with a thread chased to fit screw of valvo cap. There is thus only one
joint in pump requiring to be made absolutely air tight viz. the joint between this
plate and the column on which it seats thus minimising the risk of leaks through
numerous joints which is very important in a pump for forming a high vacuum.
T
1007

page_text: I, ALEXANDER CONACHER of Augusta in the County of Richmond and State of
Georgia in the United States of America but at present of 51 Thames Street, Windsor
in the County of Berks, Gentleman, 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:-—
This invention consists of an air or vacuum pump, of improved construction and
specially applicable to refrigerating machines.
In the accompanying drawings Figure 1 is a vertical longitudinal section through
the pump, Figure 2 an enlarged vertical section through the valves, and Figures 3 and 4
sectional views of modified constructions of the valves.
This air pump consists of two perpendicular pump barrels or columns A resting on
a horizontal pipe or closed chamber B. This latter has a crank shaft C passing along
its centre longitudinally one end of shaft having a bearing in a boss bored in the
interior of centre of one end of said pipe or chamber B and the other end of shaft
passing out through the opposite end of pipe with bearing and stuffing box. The boss
and the stuffing box may as here shown be in covers screwed on the ends of pipe or
chamber B. This crank shaft C has two cranks placed oppositely to each other each
of which is directly below the centre of one of the upright pump barrels A named.
A piston D is fitted to work in each of the upright barrels A, and these pistons are
operated from their respective cranks by connecting rods E. The tops of the barrels A
are domed and in the centre of the dome parts A a circular metal plate F is seated
having the seats of the suction and discharge valves of the pump. The suction pipe G
leading to pump barrel is screwed into a recess bored down into the centre of the top
side of this plate or otherwise united thereto. k is a vacuum gauge. The suction
valve H is made of a metal plate faced with leather or other suitable material not
affected by hydrocarbon oils; use by preference "dermatine." It seats on the centre
of the underneath side of the plate F having its tubular stem H' passing through and
fixed to this plate and extending upwards inside the suction pipe G for a length
exceeding the length of the stroke of the pump. This valve seat is formed of a beading
or projection on the underneath side of the valve seat plate F making the seat of the
valve lower than the rest of the plate by say th inch to in. The metal disc of suction
valve H is made larger in diameter than the beading on which the valve seats and the
outer edge is cupped upwards to a sufficient height to ensure the recess formed holding
the dermatine or leather facing and also to ensure that the top edge of this cup shall
when the valve is seated be above the level of the bottom of the beading which forms
the valve seat. Or 1 may as shown in Figure 3 omit the dermatine facing and make the
beading conical or wedge shaped in section and cause the said beading to seat itself
direct against a corresponding conical part recessed in the valve H. "A number of

page_text: holes are drilled round the centre hole through which the valve stem passes and inside
the beading forming the seat. These holes form the inlet from the suction pipe G
into the pump barrel A. The valve stem H' is made of pipe closed at the top end but
passing down through valve and valve plate and open at the lower end. The discharge
valve I consists of a disc of dermatine, leather or other suitable material resting on top
side of plate F and with its centre cut out to let it pass over the suction pipe G, and a
number of holes are drilled through the plate F which form outlets from pump barrel
and over which the valve rests. The top face of the plate F is formed with annular
grooves to reduce the bearing surface of the valve I. A domed cap A' is fitted to
screw or bolt on to the barrel A and over the plate F to make the latter seat tightly
on top of barrel or column A. There is a hole in centre of top of dome to admit the
suction pipe G passing down through it, and an outlet at the side for discharge pipe K
to be screwed into the bottom of this discharge outlet K being slightly above the
level of the seating of the discharge valve I. The discharge pipe K from each
barrel leads into a trap cylinder or perpendicular pipe I placed on the top of the
horizontal pipe or chamber B which connects the two pump barrels below. The trap
cylinder L is open to the air at top but covered with a light cover.
The pump pistons D are formed as to their upper side to fit the shape of the top of
the pump barrels and are of sufficient thickness to admit of a recess being made in the
centre of each on the top side to receive the bottom of the suction valve H at the
end of the upstroke while the rest of the face of piston fits close up to the bottom of
discharge valve seat and dome. In the centre of this recess in top of piston a small
perpendicular rod M is fixed the upper end of which enters into the hollow stem H'
of the suction valve, room being left in the latter by an elastic ring or spring or springs
being affixed to the suction valve so as to clasp or hold the rod with any desired tension
or friction. Or a spring or springs may be fixed to the rod M as here shown in
Figures 2 and 3. Or I form the rod itself as a spring as shown in Figure 4
where the rod is cut down with a saw, and the two parts of same bent or bulged so
as to form springs.
Each discharge valve I has a metal washer or ring I on top and is held to its seat by
a helical spring 12 pressing between the ring I and the interior of the
cap or
dome A¹.
The suction valves H are held up to their seats by helical spring H2 around the
valve stem H, and the travel of the suction valves is limited by stops on the hollow
spindles or stems E' which allow of said valves opening to a sufficient extent when
the stops strike on the top of the bearing pieces g in the pipe G. The stops h also
serve to guide the stem H¹ in the pipe G.
A small groove a Figure 2 is provided in the lower part of each pump cylinder A
reaching slightly above the top of the piston when it is at its lowest point in the pump.
Or instead of this groove I may fit a small pipe connected to the lower part of each
barrel the other end of this pipe being inserted into the horizontal chamber B forming
the base of the pump barrels.
The crank shaft is driven by hand or other power in the usual way.
To operate the pump some hydrocarbon oil having a boiling point of 450 to 600° F
is poured into the pump until it fills the whole space up to the under sides of the
pistons and fills part of the trap cylinder L. The pump being operated a very high
vacuum is obtained as at each stroke of each piston when it passes below the small
groove a near bottom of column a minute quantity of oil is passed up through the
groove a and on to top of piston, and towards the end of stroke this oil fills up the
space between top of piston and interior of dome A¹ of column, pressing every particle
of air or vapor out through the discharge valve I and thence into the trap cylinder L
and thus liquid-sealing the discharge valve. The suction valve H is mechanically opened
at the beginning of the downward stroke of the piston by the small rod M which rises
from top of centre of piston and passes up the interior of the hollow valve stem H'.
The springs press against the interior of the latter, their friction thus pulling the.
suction-valve open the proper distance but just before the end of the down stroke of

page_text: the piston the rod M passes so far out of the stem H' that the springs on the rod
cease to act on the stem H³, and the helical spring H2 then pushes the valve H to its
seat, while the cup forming a raised rim around the valve H ensures the valve seat
being covered with oil and being liquid-sealed, thus preventing any of the air or
vapor drawn into the pump escaping through the suction valve.
This pump differs from the one patented to Conacher and Williams 2nd November
1886 No. 16082 in the construction of the barrels or cylinders, the simplicity of its
form, its compactness and relative cheapness; the almost entire absence of joints liable
to leak under high vacuum, and the novel simple and effective construction of the
valves, the method of opening the suction valves and of liquid-sealing the same; also
in the automatic discharge of a small portion of oil into the pump at each stroke to
ensure complete discharge of all air or vapor at each stroke.
The oil beneath the pistons being exposed to the atmospheric pressure through the
top of trap cylinder L being open, ensures the pistons doing good work even if they
do not fit the interior of barrels very closely. The piston is formed of a pump leather
fitted over a plate which is underneath it and having a metal "piston head" to fit the
shapo of barrel as before named resting on the top of the leather; the plate is screwed
up to this piston head or block, the leather being cut away for the purpose in the centre
or I may use a solid metal piston which may be formed with one or more grooves in
its wearing surface as is well known. The chamber B forming the base of pump
is cast in two pieces each piece forming the base of a column A attached to it by
flanges. These pieces are enlarged in their diameter where they enclose the cranks so
as to allow of a sufficient length of stroke. A small gutter or depression is left in the
bottom of the chamber below each barrel and formed with a boss to attach a pipe N
and cock to empty the pump. Each barrel A being cast in one piece with a seat turned
on top to receive the plate I, and with a thread chased to fit the scrow of the dome
cap A or with a flange and bolts, there is thus only one joint in pump requiring to be
made absolutely air tight viz. the joint between the plate F and the column on which
its seats thus minimizing the risk of leaks through numerous joints which is very
important in a pump for forming a high vacuum. Or the barrel A and plate F may
be cast in one piece as shown in Figure 3.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is :-
First. The construction of air or vacuum pump substantially as described and
shown.
Second. The pump barrels AA in combination with a chamber B to which they are
fixed and which is filled with a suitable hydrocarbon oil: the pistons D D, passages a
in the barrels A for the purpose of at each stroke passing some oil from the chamber B
up past the pistons; connecting rods E for working said pistons from a crankshaft C
having its bearings in the chamber B; recessed suction valves H having hollow
stem which are guided in the suction pipes G the valves being opened by rods M
which are fixed to the pistons and have springs that enter the stems H' and the valves
being closed by helical springs H'; annular delivery valves I working on the suction
pipes G and having helical springs to assist their closing, the said suction and delivery
valves being arranged on a plate or diaphragm F in an upper part A' of pump barrel;
and a delivery pipe K from each part A leading to an oil trap L which is open below
to the oil chamber B and open above to the atmosphere substantially as described and
shown.
Third. The pumps A A mounted in an oil chamber B and provided with pistons D
worked from crankshaft C, said pistons being recessed for the suction valve H to enter
and provided with rods M with upper spring fitted ends for opening said valves by
friction against the interior of the hollow valve stems H¹ substantially as described
and shown.
Fourth. The diaphragm or plate F in upper part of pump barrel A in combination

page_text: with dome top A' having delivery pipe K; the recessed suction valve H having
hollow stem H for a rod M in pump piston to open it and a spring H' to close it,
stops and being provided for limiting its stroke substantially as described and
shown.
Fifth. The grooved diaphragm or plate F in upper part of pump barrel in combi-
nation with delivery valve I, spring 12 and suction pipe G which serves as guide for
the stem of the suction valve substantially as described and shown.
Sixth. The constructions of valve shown in Figures 2, 3 and 4.
Dated this 25th day of October 1887.
ALEXANDER CONACHER.
By Jensen & Son,
77, Chancery Lane, London, W.C.,
Patent Agents.