AIR PUMPS FOR THE COMPRESSION OF AIR BY THE MEDIUM OF WATER
Year: 1872

page_text: LETTERS PATENT to Edward Louis Paraire, of Mornington Crescent,
Regent's Park, in the County of Middlesex, Architect and Civil
Engineer, for the Invention of "AIR PUMPS FOR THE COMPRESSION OF
AIR BY THE MEDIUM OF WATER."
Sealed the 9th July 1872, and dated the 16th January 1872.
PROVISIONAL SPECIFICATION left by the said Edward Louis Paraire
at the Office of the Commissioners of Patents, with his Petition,
on the 16th January 1872.
I, EDWARD LOUIS PARAIRE, of Mornington Crescent, Regent's Park,
in the County of Middlesex, Architect and Civil Engineer, do hereby
declare the nature of the said Invention for "AIR PUMPS FOR THE COM-
PRESSION OF AIR BY THE MEDIUM OF WATER," to be as follows:-
The chief object of this Invention is to avoid the production of heat
consequent on the compression of air. To this end I have designed a
novel arrangement, which consists in a cylinder, at each extremity of
which is placed a chamber of any form, providing that at the commence-

page_text: ment of the stroke the largest surface shall be exposed, and at the end
of the stroke the smallest form of this chamber may be that of a conc, a
pyramid, or any combination of form, so long as the capacity of the
chamber shall be equal to the displacement produced in the cylinder.
In the cylinder I place a piston of metal, wood, or other substance
that is fitted therein, so as to leave between the piston and cylinder so
much space only as can mechanically be left, that there be no immediate
contact. The piston is kept in the axis of the cylinder by being carried
on a rod working through stuffing boxes fixed at both extremities.
The piston is grooved with the view of allowing the retention round
the piston of a small portion of the compressing medium, which prevents
any important escape of the water from one side of the piston to the
other.
The piston may be actuated by any mechanical action that will give a
forward and backward motion.
The cylinder and chambers adjusted I enclose the whole by valve plates
on each side, & having each an inlet and outlet valve, these being com-
mensurate with the smallest area required for effectual working.
The piston drawn to the head of the cylinder, the lower portion is
by means of taps or other contrivances filled with water or other fluid
suitable for use as a compressing medium. The piston propelled forward
forces the water up to the seat of the valves. The top of the cylinder is
filled with water or other fluid in the same manner which the return
stroke of the piston forces up to the seat of the valves appertaining to
that side.
.
The action of the pump consists in the rise and fall of the compressing
medium. The piston receding the medium falls, producing a vacuum
in the chamber. The inlet valve is open, the chamber filled with air.
The forward motion of the piston causes the water to rise in the
chamber. The air suddenly compressed opens the outlet valve. The
air is forced through, and by means of pipes is conveyed into any desired
recipient. The water in the other chamber following the back throw of
the piston the chamber is emptied, the return stroke raises the water,
& compresses the air.
As the compressing medium is not affected by pressure, and is easily :

page_text: I avail myself of this advantage, that at the commencement of the stroke
the compressing power shall be spread over an area much larger than
that of the piston. At the full power of the stroke it shall be nearly
equal to the area of the piston, and at the end of the stroke, where the
power is at its weakest, the area of the compressing medium shall be
reduced to the minimum.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Louis Paraire in the Great Seal Patent
Office on the 16th July 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
LOUIS PARAIRE, of Mornington Crescent, Regent's Park, in the County
of Middlesex, Architect, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of January, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Edward Louis Paraire, Her special licence
that I, the said Edward Louis Paraire, my executors, administrators,
and assigns, or such others as I, the said Edward Louis Paraire, 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 "AIR PUMPS
FOR THE COMPRESSION OF AIR BY THE MEDIUM OF WATER," upon
the con-.
dition (amongst others) that I, the said Edward Louis Paraire, my
exccutors 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Louis Paraire, do hereby.
declare the nature of my said Invention, and in what manner the same

page_text: is to be performed, to be particularly described and ascertained in and
by the following statement:-
My Invention relates to certain improvements in pumps for pumping
and compressing air, the object of such improvements being to decrease
the friction and heat which is produced by the compression of air by
any known form of air pump, and also to effect a saving of motive power
used for driving such pumps. To effect these objects I fix a piston in a
cylinder so that they shall not touch, but that a very small space shall
intervene between the periphery and the face of the cylinder, and there
thus being no contact friction between the surfaces of the piston and 1
cylinder is avoided.
Round the periphery of the piston are grooves or indentations that
retain a portion of the water, oil, or other fluid used as a compressing
medium when passing between the face of the cylinder and the piston. .
1
The ends of the cylinder may be of any form, providing there be left 1
between each head of the cylinder and the face of the piston sufficient
space to allow of a large port hole through which the compressing
medium may flow freely to and from the compressing chambers.
The compressing chambers may be in the form of a pyramid or cone,
or in any form which will allow of a regular graduation of the sectional 2
area of the compressing chamber.
The capacity of each chamber should be equal to the displacement of
the piston.
By the peculiar form of the compressing chambers the sectional area
of the compressing medium is most reduced at the end of the stroke or
its weakest part, and the volume of air acted upon also reduced in the
same proportion. The bulk of air left within the chamber is pro-
portional to the force. I thus effect a saving in power.
2
I have explained in my Provisional Specification the operation of the
pump, and the effect produced by causing the water filling the compress- 3
ing chambers to fall and rise, following the motion of the piston. The
fall of the water producing in the compressing chamber a vacuum,
which is filled with air through the inlet valve, the rise of the water
compressing the air and then expelling it through the outlet valve. I
make good any waste of water in the compressing chambers by allowing a
a compensating quantity to enter through the inlet valve.

page_text: The Drawings which illustrate this my Invention consist of a trans-
verse section of the pump, Figure 1; a longitudinal section of the
pump, Figure 2; a sectional plan of the inlet and outlet valves,
Figure 3; a plan over all, Figure 4; and a section of piston shewing
the grooves or indentations, Figure 5.
Having described the nature of my said Invention, and in what
manner the same is applied, I declare that I do not confine myself to
the precise details herein given, as the same may be varied without
departing from the main features or the particulars of my Invention.
What I claim is, the construction of air pumps provided with compress-
ing chambers contrived and graduated in such a way that both the
sectional area of the compressing medium and the volume of air acted
upon thereby become increased and reduced in proportion to the force of
the motive power, substantially as herein-before described.
In witness whereof, I, the said Edward Louis Paraire, have here-
unto set my hand and seal, this Sixteenth day of July One
thousand eight hundred and seventy-two.
1