IMPROVEMENTS IN AIR-COMPRESSORS."
Year: 1881

page_text: LETTERS PATENT to Alfred Chapman, of the Firm of Fawcett, Preston, and
Company, of Liverpool, in the County of Lancaster, Engineers, for an
Invention of "IMPROVEMENTS IN AIR-COMPRESSORS."
PROVISIONAL SPECIFICATION left by the said Alfred Chapman at the
Office of the Commissioners of Patents on the 2nd September 1881.
ALFRED CHAPMAN, of the Firm of Fawcett, Preston, and Company, of Liverpool,
in the County of Lancaster, Engineers. "IMPROVEMENTS IN AIR COMPRESSORS."
When the inlet valves of air compressors are made of india-rubber, which is in
most respects the best material for them, it is found that the compressed air makes
the guards so hot that the india-rubber is liable to burn and stick, and it therefore
quickly wears away or gets out of shape.
Now the object of my Invention is to keep down the temperature of the guards
of the valves to a point which is innocuous to the india-rubber, and for this
purpose I make the guards hollow and cause water to circulate freely through
them. The entering air keeps the seats cool, and thus I get all the advantages
offered by india rubber valves without the disadvantages which have hitherto
attended their use.
The water enters the hollow guard by an inlet placed at any suitable position,
and after circulating through it leaves by a suitably placed outlet.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alfred Chapman in the Great Seal Patent Office on the
2nd March 1882.
ALFRED CHAPMAN, of the Firm of Fawcett, Preston, and Company, of Liverpool,
in the County of Lancaster, Engineers. IMPROVEMENTS IN AIR COMPRESSORS."
"
When the inlet valves of air compressors are made of india rubber, which is in
most respects the best material for them, it is found that the compressed air makes
the guards so hot that the india rubber is liable to burn and stick, and it therefore
quickly wears away or gets out of shape.
Now the object of my Invention is to keep down the temperature of the guards
of the valves to a point which is innocuous to the india rubber, and for this
purpose I make the guards hollow and cause water to circulate freely through
them. The entering air keeps the seats cool, and thus I. get all the advantages
offered by india rubber valves without the disadvantages which have hitherto
attended their use.
The water enters the hollow guard by an inlet placed at any suitable position,
and after circulating through it leaves by a suitably placed outlet.
The manner in which I carry my Invention into effect is represented in the
annexed Drawings. Figure 1 is a longitudinal section of an air compressor
showing the valves, and Figure 2 is a transverse section through the line A, B,
of Figure 1. a is the cylinder of the compressor, and b the piston; c, c, are the
air inlets in the cylinder end; d is the india rubber inlet valve; e is the guard of
the valve d. I make this guard hollow, as shown, and cause water to circulate
freely through it. The water enters by the inlet f, and after circulating through
the guard leaves by the outlet G.
Having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim,-
Constructing air compressors with the guards of the inlet valves made hollow,
and causing water to circulate through the said guards, substantially as and for
-the-purpose-herein before-described-and-shown-in-the-accompanying-Drawings.-
In witness whereof, I, the said Alfred Chapman, have hereunto set my hand
and seal, this Twenty eighth day of February, One thousand eight hundred
and eighty twa
ALFRED CHAPMAN. (L.S.)