Improvements in connection with Refrigerating Machines.
Year: 1898

page_text: Date of Application, 27th Oct., 1898-Accepted, 3rd Dec., 1898
COMPLETE SPECIFICATION.
Improvements in connection with Refrigerating Machines.
We, EVERARD HESKETH and ALEXANDER MARCET, both of 23, St. Swithin's Lane, in
the City of London, Engineers, 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 :--
Our invention relates to the valves in connection with the air expansion cylinders
of refrigerating machines and has for its object to prevent loss of pressure and
undue rise of temperature by the passage of unexpanded air from the expansion
cylinder into the snow box of the apparatus.
Our invention will be clearly understood from the following description with
reference to the accompanying drawings of which Figure 1 represents in longitu-
dinal section and Figure 2 in transverse section an air expansion cylinder provided
with our improvements. A is the air expansion cylinder to which compressed air
is admitted by a valve B in the usual manner. Care valves by which the expanded
It is important for the
air passes from the cylinder A into the snow box D.
satisfactory working of the refrigerating machine that outlet valves C work tightly
in their seats or bushes so as to prevent unexpanded air from passing from the
cylinder A into the snow box, and the object of our invention is to render the said
outlet valves air-tight in their seats even when they become somewhat worn.
According to our invention we provide in the seats or bushes C¹ in which the valves
C work grooves c which become filled with snow carried by the cold air exhausting
from the cylinders, the said snow collecting in the grooves c and forming an air-
tight packing between the valves C and their seats or bushes C. Instead of
providing grooves in the valve seats, C¹, the said seats may be smooth, and grooves
be provided in the valves as shewn at d, or if desired grooves may be provided both
Grooves may be provided in the bushes
in the valves and in their seats or bushes.
on only the sides of the ports which are nearest to the snow box or additional grooves
may be provided on the opposite sides of the ports as shewn at C*.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a refrigerating machine having an air expansion cylinder the combination
with an outlet valve for the expanded air of a groove or grooves in the said valve
or in its seat or in both the valve and its seat, in which groove or grooves, snow can
accumulate to prevent the passage of unexpanded air from the cylinder sub-
stantially as hereinbefore described.
2. In a refrigerating machine having an air expansion cylinder the combination
therewith of a piston outlet valve for the expanded air, and a groove or grooves in
the valve or in the seat or bush in which it slides, in which groove or grooves

page_text: snow can accumulate so as to form a packing between the valve and its seat to prevent
the passage of unexpanded air from the cylinder, substantially as hereinbefore
described.
Dated this 27th day of October 1898
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.