Improvements in the Valve Motion of the Expansion Cylinders of Vapour Compression Refrigerating Machines.
Year: 1891

page_text: Date of Application, 15th Sept., 1891
Complete Specification Left, 2nd June, 1892-Accepted, 2nd July, 1892
PROVISIONAL SPECIFICATION. ·
Improvements in the Valve Motion of the Expansion Cylinders of
Vapour Compression Refrigerating Machines.
I, EMIL RIEGELMANN of Georgenstrasse, 88, Augsburg, Germany, Engineer,
do hereby declare the nature of this invention to be as follows:-
The refrigerating liquid, such for instance as carbonic acid, ammonia, sulphurous
acid, pictet-liquid, or the like, coming from the condenser of a vapour, compression
engine, possesses a certain capacity for doing work, before it enters the refrigerato
where it produces cold, by evaporation....This work can be utilized by allowing
the refrigerating liquidion its way from the condenser to the refrigerator to expand
and do work in a cylinder,. the so-called expansion cylinder. Fig. 1 illustrates the
general arrangement of a vapour compression engine of this kind. The gas which
is drawn out of the refrigerator. R through the pipe Band valves A is compressed
in the cylinder. S....The compressed gas is supplied by means of the delivery.
valves C through the pipe. D.to the condenser K, in which it is liquefied by, being
cooled. The refrigerating liquid now passes, through the pipe. and inlet valves F
into the expansion cylinder I in which it does work that is given off to the com-
pression cylinder S. The mixture of expanded gas and liquid is conveyed by
means of the valves L. and the pipe, M. to the refrigerator R in which cold is
produced in the well known.manner....
:
The refrigerating liquid thus travels in a.continual cycle.in the direction of the
arrows.
Whereas heretofore the inlet valves F and the outlet valves of the expansion
cylinder, have been operated by a mechanical valve-motion, now. according to the
present invention, the difference in the pressures in the condenser, and in.. the
refrigerator is employed to operate those valves. This arrangement is illustrated to
a larger scale in Fig. 2, applied to a vapor.compression engine, whose, compression
cylinder is combined with the expansion cylinder iu such a manner, that in the
right hand half, S of the cylinder compression is effected, whilst expansion takes
place in the left half, T.
BE
The various pipes and valves are marked with the same letters of reference, as
in Fig. 1. The inlet valve F of the expansion, half of the cylinder is connected
with a piston.G which is capable of working fluid-tight in a cylindrical casing...
The space a above the piston G communicates by means of a pipe b with the
pipe D leading to the condenser, K, and by means of a pipe c with the chamber d
of the distributing, valve J, which is pressed against. its seat by. a spring. The
chamber of this valve is connected by a pipe 9.with the suction. pipe B.coming
from the refrigerator BA throttle valve H is inserted in the pipe b.. The outlet
valve L of the expansion half T of the cylinder is pressed against its seat by a
spring, h, and the prolonged ralva rod works in a closed chamber which is connected
by a pipe m with the pipe c..
1
"
As soon as the piston, is, about to complete its movement to the left in the
direction of the arrow, it strikes, against the rodip, of the valve. J, so that the
latter opens and communication is made. between the chambers d and fIn con
sequence of this, the gas contained in the chambera of the inlet valve F, can pass
through the pipe.tod, through the open valve J. to f, and through pipe 9. to the
pipe B, where a much less pressure exists than in the pipe D.
1.
The throttle valve. prevents a too:quick.rush of gas through pipe to the
space a; and in consequence of the decrease in pressure in this space a the piston G
rises in response to the pressure on the opposite side, the valve opens and the
condensed refrigerating liquid flows.out of pipa E into the expansion, balf of the

page_text: cylinder. The piston P moves to the right, and immediately after the beginning
of this movement the distributing valve J is closed again by the action of its
spring, so that the communication between the spaces d and fis interrupted, and
gas can no longer flow from the space a to the pipe B. In consequence of this the
pressure in the space a soon increases, so that the valve F is again closed. The
duration of this equalizing of pressure is determined by means of the throttle
valve H. The more the latter is opened, the quicker the valve F is closed, and
the smaller is the charge. If it be desired to dispense with this variation of the
extent of charge, the throttle valve H can be replaced by a mere fine opening.
During the further movement to the right, the refrigerating liquid expands in
the expansion half T of the cylinder and performs work, by evaporating to a
partial extent, until it has assumed the pressure in the refrigerator, at which
moment the outlet valve L opens, and communication is made between the expansion
half T of the cylinder and the refrigerator through pipe M. In this operation
the pressure of the spring of this valve is balanced by the pressure of the
condenser acting in the chamber upon the valve rod. But as soon as in con-
sequence of the opening of the distributing valve J, the pressure in pipe c and
consequently also in pipe m diminishes, with consequent diminution of the pressure
upon the spindle of valve L, the latter will be closed by the spring h. This is
effected towards the end of the movement of piston P to the left. During the
admission and expansion the valve L is kept olosed by the pressure in the left
hand end of the cylinder T until the pressure in this space falls to the pressure in
the refrigerator.
Instead of the outlet valve L operated as described there may be employed_a
valve which is closed in a mechanical manner directly by means of the piston P,
and is similarly kept closed by the pressure in the space T during the admission
and expansion, until the pressure in the space T falls to the pressure in the
refrigerator.
If in this case the valve L be provided with a pin so that it is closed just before
the end of the piston's stroke, a certain amount of compression will be produced
in the expansion cylinder.
Finally the outlet valve L may be caused to close automatically by means of a
second distributing valve. Fig. 3 illustrates this modification. The said distributing
valve J is arranged, instead of in the cylinder cover, externally to the same in a
separate casing in such a manner that the valve rod projecting from the casing is
struck by an arm P' adjustably fixed on the piston rod, thereby opening the
valve.
The valve L is in this case, modified as regards the construction shown in Fig. 2,
inasmuch as on its rod there is fixed a piston g' which moves in a suitable casing
and divides the latter into two spaces and P. The space A communicates by a
pipe m' with one chamber of the casing of the distributing valve J', whose other
chamber is connected with the condenser or with the pressure pipe of the latter.
In the space is arranged the spring which opens the valve Las soon as the
pressure in the space T of the cylinder is equal to or smaller than the pressure in
the chamber 1.
The chamber communicates by a pipe m² with the refrigerator or with the
pipe of the latter. The operation of this modification is as follows:-
At the end of the exhaust period, the valve J' is struck and opened by the
arm P' fixed on the piston rod, whereby the pressure in the chamber l' of the
outlet valve rises to condenser pressure, and closes the valve L by excess of
pressure upon the piston g'. During the next following period of admission and
expansion, the pressure escapes from the chamber to the refrigerator through the
small space a, or through a pipe in substitution of the said space a, leading from /
to the refrigerator pipe, and provided with a throttling cross section or with a
throttle valve, so that at the end of the expansion period refrigerator pressure
exists in the chamber l.
Now as the chamber is constantly under refrigerator pressure, the piston g' is

page_text: now without influence on the valve L; the latter is solely under the influence of
the spring which opens it as soon as the pressure in the expansion space T has
fallen to refrigerator pressure..
The distributing valve J' might be arranged in the cylinder cover similarly to
the distributing valve J shewn in Fig. 2, and be opened by direct impact of the
piston.
Also, the valve J of the first described arrangement can, similarly to the valve J',
be arranged externally to the cylinder cover in a separate casing, and the rod p be
actuated by an arm fixed on the piston rod similar to the arm P³, or by any other
suitable part of the engine.
In a double acting expansion cylinder, it will be evident that each end of the
cylinder will receive the same arrangement. Instead of transmitting the work of
the expansion cylinder to the compression cylinder, the said work may be utilized
in any other manner, as for example in an independent motor.
Dated this 15th day of September 1891.
E. RIEGELMANN,
By L. W., per F. B.
COMPLETE SPECIFICATION.
Improvements in the Valve Motion of the Expansion Cylinders of
Vapour Compression Refrigerating Machines.
I, Emil Riegelmann of Georgenstr., 88. Augsburg, Germany, Engineer, 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:
The refrigerating liquid, such for instance as carbonic acid, ammonia, sulphurous
acid, pictet-liquid, or the like, coming from the condenser of a vapor compression
engine, possesses a certain capacity for doing work, before it enters the refrigerator
where it produces cold by evaporation. This work can be utilized by allowing the
refrigerating liquid on its way from the condenser to the refrigerator; to expand
and do work in a cylinder, the so-called expansion cylinder. Fig. 1 illustrates the
general arrangement of a vapor compression engine of this kind. The gas which is
drawn out of the frigerator R through the pipe B and valves A, is compressed in
the cylinder S. The compressed gas is supplied by means of the delivery valves C
through the pipe D to the condenser K, in which it is liquefied by being cooled.
The refrigerating liquid now passes through the pipe E and inlet valves Finto the
expansion cylinder Tin which it does work that is given off to the compression
cylinder S. The mixture of expanded gas and liquid is conveyed by means of
the valves L and the pipe M to the refrigerator R in which cold is produced in the
well known manner.
The refrigerating liquid thus travels in a continual cycle in the direction of the
arrows.
Whereas heretofore the inlet valves F and the outlet valves L of the expansion
cylinder have been operated by a mechanical valve-motion, now according to the
present invention, the difference in the pressures in the condenser and in the
refrigerator is employed to operate those valves. This arrangement is illustrated
to a larger scale in Fig. 2, applied to a vapor compression engine, whose compression
cylinder is combined with the expansion cylinder in such a manner that in the right
hand half S of the cylinder compression is effected, whilst expansion takes place in
the left half T.
The various pipes and valves are marked with the same letters of reference, as in
Fig. 1. The inlet valve F of the expansion half of the cylinder is connected with
a piston G which is capable of working fluid-tight in a cylindrical casing.
The space a above the piston G communicates by means of a pipe b with the
pipe D leading to the condenser K, and by means of a pipe c with the chamber d of

page_text: the distributing valve J, which is pressed against its seat by a spring. The
chamber of this valve is connected by a pipe g with the suction pipe B coming
from the refrigerator R. A throttle valve H is inserted in the pipe b. The outlet
valve L of the expansion half.T of the cylinder is pressed against its seat by a
spring, and the prolonged valve rod works in a closed chamber which is connected
by a pipe m with the pipe c.
As soon as the piston P is about to complete its movement to the left in the
direction of the arrow, it strikes against the rod p of the valve J, so that the latter
opens and communication is made between the chambers d and f. In consequence
of this, the gas contained in the chamber a of the inlet valve F, can pass through
the pipe c to d, through the open valve J to f, and through pipe g to the pipe B,
where a much less pressure exists than in the pipe D.
The throttle valve H prevents a too quick rush of gas through pipe 6 to the
space a; and in consequence of the decrease in pressure in this space a the
piston G rises in response to the pressure on the opposite side, the valve F opens
and the condensed refrigerating liquid flows out of pipe E into the expansion
half of the cylinder. The piston P moves to the right, and immediately after
the beginning of this movement the distributing valve J is closed again by the
action of its spring, so that the communication between the spaces d and fis
interrupted, and gas can no longer flow from the space a to the pipe B. In
consequence of this the pressure in the space a soon increases, so that the
valve F is again closed. The duration of this equalizing of pressure is deter-
mined by means of the throttle valve H. The more the latter is opened, the
quicker the valve F is closed, and the smaller is the charge. If it be desired
to dispense with this variation of the extent of charge, the throttle valve H can
be replaced by a mere fine opening.
During the further movement to the right, the refrigerating liquid expands in
the expansion half T of the cylinder and performs work, by evaporating to a
partial extent, until it has assumed the pressure in the refrigerator, at which
moment the outlet valve L opens, and communication is made between the
expansion half T of the cylinder and the refrigerator through pipe M. In this
operation the pressure of the spring h of this valve is balanced by the pressure
of the condenser acting in the chamber upon the valve rod. But as soon as
in consequence of the opening of the distributing valve J, the pressure in pipe c
and consequently also in pipe m diminishes, with consequent diminution of the
pressure upon the spindle of valve L, the latter will be closed by the spring h.
This is effected towards the end of the movement of piston P to the left.
During the admission and expansion the valve L is kept closed by the pressure
in the left hand end of the cylinder T until the pressure in this space falls to
the pressure in the refrigerator.
Instead of the outlet valve L operated as described there may be employed
a valve which is closed in a mechanical manner directly by means of the
piston P, and is similarly kept closed by the pressure in the space T during
the admission and expansion, until the pressure in the space T falls to the pressure
in the refrigerator.
If in this case the valve L be provided with a pin so that it is closed just before
the end of the piston's stroke, a certain amount of compression will be produced in
the expansion cylinder.
Finally the outlet valve L may be caused to close automatically by means of a
second distributing valve. Fig. 3 illustrates this modification. The said distributing
valve J' is arranged, instead of in the cylinder cover, externally to the same in a
separate casing in such a manner that the valve rod projecting from the casing is
struck by an arm P² adjustably fixed on the piston rod, thereby opening the valve.
The valve L is in this case, modified as regards the construction shown in Fig. 2,
inasmuch as on its rod there is fixed a piston g' which moves in a suitable casing
and divides the latter into two spaces and P. The space communicates by a
pipe with one chamber of the casing of the distributing valve J³, whose other

page_text: chamber is connected with the condenser or with the pressure pipe of the latter. In
the space is arranged the spring h' which opens the valve L as soon as the
pressure in the space T of the cylinder is equal to or smaller than the pressure in
the chamber /¹.
The chamber communicates by a pipe m³ with the refrigerator or with the pipe
of the latter. The operation of this modification is as follows:-
At the end of the exhaust period, the valve J' is struck and opened by the arm P¹
fixed on the piston rod, whereby the pressure in the chamber of the outlet valve
rises to condenser pressure, and closes the valve L by excess of pressure upon the
piston g'. During the next following period of admission and expansion. the
pressure escapes from the chamber to the refrigerator through the small space s
or through a pipe in substitution of the said spaces, leading from 1 to the refrigerator
pipe, and provided with a throttling cross section or with a throttle valve, so that at
the end of the expansion period refrigerator pressure exists in the chamber I.
Now as the chamber is constantly under refrigerator pressure, the piston g' is
now without influence on the valve L; the latter is solely under the influence of
the spring which opens it as soon as the pressure in the expansion space T has
fallen to refrigerator pressure.
The distributing valve J' might be arranged in the cylinder cover similarly to
the distributing valve J shown in Fig. 2, and be opened by direct impact of the
piston.
Also, the valve J of the first described arrangement can, similarly to the valve J³,
be arranged externally to the cylinder cover in a separate casing, and the rod p be
actuated by an arm fixed on the piston rod similar to the arm P, or by any other
suitable part of the engine.
In a double acting expansion cylinder, it will be evident that each end of the
cylinder will receive the same arrangement. Instead of transmitting the work of
the expansion cylinder to the compression cylinder, the said work may be utilized
in any other manner, as for example in an independent motor.
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 :-
1. In a vapor compression engine, an automatic valve motion for the expansion
cylinder, comprising a distributing valve such as J which, at the end of the piston's
stroke, effects communication between a space such as a above a piston G controlling
the motion of the inlet valve, and the refrigerator, whilst the entry of the gas into
the said space a from the condenser is throttled, substantially as described.
2. In combination with a space, such as a, in communication with the condenser
and the refrigerator as referred to in Claim 1, the chamber and spring / to effect
the closure of the outlet valve L, substantially as described.
3. The modified arrangement of the outlet valve L, the said outlet valve being
connected to a piston g', which is placed under condenser pressure at the end of the
exhaust period by means of a distributing valve J' operated by the piston (P) or
by an arm P, and thereby closes the outlet valve, substantially as described.
4. The adjustable regulating throttle valve H in the pipe b leading from the
condenser to the space a referred to in Claim 1, for the purpose of obtaining variable
admissions, substantially as described.
Dated this 2nd day of June 1892.
E. RIEGELMANN,
By L. W., per F. B.