IMPROVEMENTS IN AND RELATING TO AIR PUMPS OR MACHINERY FOR DRAWING AIR OUT OF OR VENTILATING BUILDINGS, SHIPS, MINES, AND OTHER STRUCTURES OR CONFINED SPACES, APPLICABLE IN PART TO BLOWING ENGINES
Year: 1880

page_text: LETTERS PATENT to John Miller, of Langholm, in the County of Dumfries,
for an Invention of "IMPROVEMENTS IN AND RELATING TO AIR PUMPS OR
MACHINERY FOR DRAWING AIR OUT OF OR VENTILATING BUILDINGS, SHIPS,
MINES, AND OTHER STRUCTURES OR CONFINED SPACES, APPLICABLE IN PART
TO BLOWING ENGINES."
for an invention of "IMPROVEMENTS IN AND RELATING TO AIR PUMPS OR
MACHINERY FOR DRAWING AIR OUT OF OR VENTILATING BUILDINGS, SHIPS,
MINES, AND OTHER STRUCTURES OR CONFINED SPACES, APPLICABLE IN PART
TO BLOWING ENGINES."
PROVISIONAL SPECIFICATION left by the said John Miller at the Office of
the Commissioners of Patents on the 28th May 1880.
JOHN MILLER of Langholm, in the County of Dumfries.
"IMPROVEMENTS IN
AND RELATING TO AIR PUMPS OR MACHINERY FOR DRAWING AIR OUT OF OR
VENTILATING BUILDINGS, SHIPS, MINES, AND OTHER STRUCTURES OR CONFINED
SPACES, APPLICABLE IN PART TO BLOWING ENGINES."
This Invention has for its object the construction of an air pump for ships and
the ventilating of ships and other buildings or structures in a superior manner than
heretofore.
I place my pump on the deck of a ship, or the basement of a building, or other
convenient position, and provide it with an air chamber or chambers to suck from.
Into the chamber or chambers the pipes brought from the various parts of the ship
or building are led. The cylinders are single or double acting, and one, two, or
three in number, connected with the crank shaft in such way as to equalise the
strain as much as possible. The piston packing for hand gear where springs are
not used I make of an india-rubber ring screwed tightly between the rings of the
piston, and tapering beyond the piston rings toward the periphery.
There are various forms in which these improvements can be arranged. One
plan is to place these cylinders on their sides and make them double acting, the
pipes being brought to each end, valves in the ends, piston, and sides (like the ports
of a steam engine, but as close as possible to the contour of the interior of the
cylinder) being employed. The cylinder lies on the windchest.
Another plan is to make the pump single acting, and place an air chamber
below, valves between the air chamber and the cylinder, in the piston, and in the
cylinder cover all opening upward. The piston rod, single or projecting through
each end, is connected to the crank shaft by a connecting rod or its equivalent, and
r.

page_text: is guided by stuffing boxes at top, by a guide bar through the hollow piston-rod, or
by a parallel motion.
When steam power is used the piston ring of tapering india-rubber sometimes
will stop in the middle of its stroke when drawn up the contracted part of the
cylinders towards the turned out recess at each end; as at this point it cannot
straighten itself out if the stroke be reversed the india-rubber jams and breaks.
To avoid this where steam power is used I do without the india-rubber ring, but
construct my piston with a disc and ring fastened together a certain distance apart
by stud bolts, place segments between the stud bolts with sufficient play for the
bolts not to interfere with them, and pack the piston with well lubricated packing
of hemp or other materials arranged so as to allow of being expanded outward.
The segments are attached to or abut against a spring or springs, which by a
ratchet and pawl or equivalent mechanism can be drawn back or be allowed to
exert a part of or the whole of their force on the segments. With this piston the
cylinder is bored parallel throughout. I also use this piston occasionally with
hand gear.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Miller in the Great Seal Patent Office on the 27th November
1880.
JOHN MILLER, of Langholm, in the County of Dumfries.
"IMPROVEMENTS IN
AND RELATING TO PUMPS OR MACHINERY FOR DRAWING AIR OUT OF OR
VENTILATING BUILDINGS, SHIPS, MINES, AND OTHER STRUCTURES OR CONFINED
SPACES, APPLICABLE IN PART TO BLOWING ENGINES."
This Invention has for its object the construction of an air pump for ships and
the ventilating of ships and other buildings or structures in a superior manner than
heretofore, which I call the acme ventilator.
I place my pump on the deck of a ship, or the basement of a building, or other
convenient position, and provide it with an air chamber or chambers from which to
suck or exhaust the air. Into the chamber or chambers the pipes brought from
the various parts of the ship or building are led. The cylinders are single or double
acting, and one, two, or three in number, connected with the crank shaft in such
way as to equalize the strain as much as possible. The piston packing for hand
gear where springs are not used I make of an india-rubber ring screwed tightly
between the rings of the piston, and tapering beyond the piston rings toward the
periphery. When this kind of piston is used I cut away the cylinder considerably
at each end to allow the india-rubber to regain the horizontal before being
dragged in the opposite direction.
There are various forms in which these improvements can be arranged. One
plan is to place these cylinders on their sides and make them double acting, the
pipes being brought to each end, valves in the ends, piston, or sides (like the ports
of a steam engine, but as close as possible to the contour of the interior of the
cylinder) being employed. The cylinder lies on the windchest.
Another plan is to make the pump single acting, and place an air chamber
below, valves between the air chamber and the cylinder, in the piston, and in the
cylinder cover all opening upward. The piston-rod-single or projecting through
each end-is connected to the crank shaft by a connecting rod or its equivalent, and
is guided by stuffing boxes at top, by a guide bar through the hollow piston-rod, or
by a parallel motion.
When steam power is used the piston ring of tapering india-rubber sometimes
will stop in the middle of its stroke when drawn up the contracted parts of the
cylinders towards the turned out recess at each end; as at this point it cannot
straighten itself out if the stroke be reversed the india-rubber jams and breaks.
To avoid this I do without the india-rubber ring, but construct my piston as here-
after described.
Referring to the Drawings, in which like letters refer to like parts, Sheet one
illustrates my air pump with one double acting cylinder arranged with the piston
working vertically, Fig. 1 being an end elevation showing the engine for working
it, Fig. 2 a sectional elevation of pumping cylinder, and Fig. 3 a plan. In these A
is the cylinder; B, the wind chest; C, the air chamber; D, the outlet passage; E,
the piston; F, piston rod; f, stuffing box; b and 6' are the inlet valves; d and d¹
are the outlet and exhaust valves; G, the connecting rod of the engine; H, rod
connecting piston rod F with the engine. Sheet two illustrates air pump when
arranged to work horizontally, with a detailed view of piston. Fig. 4 is a sectional
elevation of double acting pumping cylinder, showing the arrangement of valves and
air chest when the piston travels in horizontally (to which the above letters refer);
Fig. 5, a sectional elevation of piston; and Fig. 6, a plan of same with half of cover
removed. K is the piston body, to which the piston rod F is attached; L is a disc
or cover secured to K by means of stud bolts M with nuts m and m²; N, packing;

page_text: O, segments placed between K and L abutting against the well lubricated packing
N of hemp or other materials arranged so as to allow of being expanded outward;
P, spring pressing against the segments O, and keeping the packing closely in
contact with the sides of the cylinder A; R, barrel round which the spring is
wound; S, ratchet wheel; and T, pawl. Fig. 7 shows a partial section of the rubber
packed piston and cylinder.
The mode of action is as follows:-When the piston E travels upwards the air in
the cylinder above the piston is driven out through the valve d' into the outlet
passage D, and the air in the chamber c―which is connected by pipes or otherwise
to that part of the building or ship which requires ventilation-is drawn into the
cylinder through the valve b on the down stroke; this air is expelled through the
valve d, and the upper part of the cylinder is again filled through the valve b¹,
which also communicates with the air chamber.
The advantages of the two forms of piston are these:-When the piston is made
of an annular piece of india rubber tapering toward its periphery and projecting a
few inches beyond the piston, into which it is firmly fixed, the piston being one and
a half inches at least less in diameter than the cylinder, and reciprocating vertically,
there is extraordinary little friction-the india rubber bends to suit the contour of
the cylinder, so that the latter need not be so accurately turned or even turned at
all. The tapering edge greatly assists the rubber to turn and drag on the sides, so
as to be air tight. The spring piston is for cylinders vertical, horizontal, or inclined.
It has one striking advantage, that the spring can be wound up tight, so as to allow
of the piston being easily entered into the cylinder; and then released.
Having now described my Invention and the best modes known to me of carrying
it into effect, I wish it to be understood that what I believe to be new and desire
to protect under the hereinbefore in part recited Letters Patent is,―
First. In a blowing or ventilating cylinder, the rubber piston packing with
tapering edge, substantially as described.
Second. In pumps or machinery for pumping air, the arrangement of piston
herein described, with a spring or springs capable of being wound up and drawn
inward when the piston is being introduced into the cylinder, and released
afterwards.
Third. The manufacture of air pumps or machinery for blowing purposes or
drawing air out of or ventilating buildings, ships, mines, and other structures or
confined spaces, consisting of a single or double acting pump or pumps erected upon
a wind chest, from which it draws the air, this wind chest being connected by pipes
to the various parts of the space or spaces to be ventilated, so that each part can
be cut off or put in communication independently of the rest.
• Fourth. The special designs or arrangements of ventilating apparatus, substan-
tially as herein described.
In witness whereof, I, the said John Miller, have hereunto set my hand and
seal, this Fourth day of November, in the year of our Lord One thousand
eight hundred and eighty.
JOHN MILLER. (L.S.)