Apparatus for Regulating the Supply of Volatile Liquid in Refrigerating Machinery.
Year: 1892

page_text: Date of Application, 23rd Apr., 1892
Complete Specification Left, 20th May, 1892-Accepted, 25th June, 1892
PROVISIONAL SPECIFICATION.
[Communicated from abroad by GESELLSCHAFT FÜR LINDES EISMASCHINEN,
of Wiesbaden, Germany, Manufacturers.]
Apparatus for Regulating the Supply of Volatile Liquid in
Refrigerating Machinery.
I, THOMAS BELL LIGHTFOOT, of 35 Queen Victoria Street, in the City of
London, Engineer, do hereby declare the nature of this invention to be as follows:-
It is usual with refrigerating machinery worked by the vaporisation of volatile
liquids, to regulate the quantity of volatile liquid flowing from the condenser to
the vaporising apparatus by means of a cock or valve controlled by hand, so
that the sectional area given for the time being to the opening of such cock or
valve according to the required conditions of pressure and output, will determine
the rate of flow of the volatile liquid.
A great disadvantage of this regulating arrangement arises from the com-
paratively very small sectional areas of flow which are required when consider-
able differences exist between the condenser and vaporising pressures, that is to
say, with high temperatures of the cooling water and with low temperatures of
the refrigerating medium, or both combined, as also with refrigerating machines
operating with small quantities of circulating refrigerating medium, because the
slightest deposit of solid particles effect a complete or partial obstruction of the
small discharge orifice, and because, generally speaking, the regulation of such
small orifices is exceedingly difficult.
According to the present invention the above mentioned defect is entirely
obviated by causing the supply of volatile liquid to the vaporiser not to take
place continuously, but intermittently at regular intervals of time which depend
upon the number of revolutions performed by the engine.
For this purpose a cylindrical or conical plug fitting accurately inside a
correspondingly shaped barrel receives a continuous or reciprocating rotary
motion by means of a cord and pulley on the plug spindle, or by other suitable
gear, from the engine of the refrigerating machine, which plug has an elbow
passage formed in it, one end of which opens at the side of the plug so as, in
rotating, to alternately face the openings of two opposite passages in the barrel,
one of which leads to the condenser while the other leads to the vaporiser,
while the other end of the elbow passage opens at the end face of the plug into
a chamber there situated.
Thus at each revolution or reciprocation of the plug the passage of the plug
and the said chamber are filled with volatile liquid coming from the condenser
and consequently subject to the pressure there existing. As soon as, by
the turning of the plug, the connection between its passage and the condenser
is cut off and that between the said passage and the vaporiser is established, an
expansion and partial vaporisation of the liquid in the said passage and chamber
will take place in consequence of the comparatively low pressure in the vaporiser,
and consequently a proportionate body of such liquid will flow to the vaporiser.
For regulating the quantity of volatile liquid which passes in this manner
according to requirements, the capacity of the said chamber is regulated by a
piston contained in the lower part thereof, such piston being raised or lowered
for this purpose by means of a screw spindle which can either be turned by
hand, or automatically by any suitable known device whose action is dependent
upon the temperature of the compressed vapours.
Dated this 92-d dove of Anril 1800
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Apparatus for Regulating the Supply of Volatile Liquid in
Refrigerating Machinery.
I, THOMAS BELL LIGHTFOOT of 35 Queen Victoria Street, in the City of
London, 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 :-
It is usual with refrigerating machinery worked by the vaporisation of volatile
liquids, to regulate the quantity of volatile liquid flowing from the condenser to
the vaporiser apparatus by means of a cock or valve controlled by hand, so that
the sectional area given for the time being to the opening of such cock or valve
according to the required conditions of pressure and output, will determine the
rate of flow of the volatile liquid.
A great disadvantage of this regulating arrangement arises from the com-
paratively very small sectional areas of flow which are required when consider-
able differences exist between the condenser and vaporising pressures, that is to
say, with high temperatures of the cooling water and with low temperatures of
the refrigerating medium, or both combined, as also with refrigerating machines
operating with small quantities of circulating refrigerating medium, because the
slightest deposit of solid particles effect a complete or partial obstruction of the
small discharge orifice, and because, generally speaking, the regulation of such
small orifices is exceedingly difficult.
According to the present invention, the above-mentioned defect is entirely
obviated by causing the supply of volatile liquid to the vaporiser not to take
place continuously, but intermittently at regular intervals of time, which depend
upon the number of revolutions performed by the engine.
For this purpose a cylindrical or conical plug fitting accurately. inside a
correspondingly shaped barrel receives a continuous or reciprocating rotary
motion by means of a cord and pulley on the plug spindle, or by other suitable
gear from the engine of the refrigerating machine, which plug has an elbow
passage formed in it, one end of which opens at the side of the plug so as, in
rotating, to alternately face the openings of two opposite passages in the barrel,
one of which leads to the condenser while the other leads to the vaporiser,
while the other end of the elbow passage opens at the end face of the plug into
a chamber there situated.
Thus at each revolution or reciprocation of the plug, the passage of the plug
and the said chamber are filled with volatile liquid coming from the condenser
and consequently subject to the pressure there existing. As soon as by the
turning of the plug, the connection between its passage and the condenser is cut
off and that between the said passage and the vaporiser is established, an
expansion and partial vaporisation of the liquid in the said passage and chamber
will take place in consequence of the comparatively low pressure in the
vaporiser, and consequently a proportionate body of such liquid will flow to the
vaporiser.
The accompanying drawing shews a vertical section of a regulating apparatus
constructed according to the above described invention.
The valve casing V contains a conical slide or plug H, fitting fluid-tight in a
corresponding conical seating of the casing, and having a spindle H passing
through a stuffing box and carrying outside a pulley or pitch wheel R, which
is driven at a suitable speed by a chain or cord from the motor engine working
the compressor of the refrigerating apparatus.
The casing V has two diametrically opposite passages K¹ and K', of which K¹
leads from the condenser, while K loads to the vaporising chambers, and the
plug H has an elbow-shaped passage K, one end of which is caused, by the rotation

page_text: of the plug, to communicate alternately with the passages K¹ and K³, while the
other end always communicates with a chamber V₁ at the under side of the plug.
Thus at each revolution or reciprocation of the plug H the passage K and
chamber V will first be filled with the volatile liquid at condenser pressure coming
from the condenser through the passage K¹, and, when the passage K arrives
opposite the passage K' leading to the vaporising chamber, the liquid contained.
in K and V will evaporate to a certain extent, owing to the lower pressure
existing in the vaporising chamber, and will consequently flow through K³ to the
latter.
The apparatus may be made to supply several vaporising chambers, in which
case there would be as many discharge passages K' as there are chambers.
For regulating according to requirements the quantity of the volatile fluid which
is thus transmitted at each revolution of the plug to the vaporising chamber, the
capacity of the chamber V' can be varied by means of a piston S which can be
shifted up and down by the screwed spindle S either by means of a handwheel T,
or automatically by any suitable thermal motor device that is rendered operative by
variation in the temperature of the compressed vapours.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1-Apparatus for regulating the supply of volatile liquid in refrigerating
machinery, consisting of a revolving or reciprocating device so arranged as to admit
such liquid intermittently from the condenser to the vaporising apparatus, while at
the same time each quantity of liquid, so transmitted is capable of being regulated
by external means, substantially as described.
2-In apparatus such as is referred to in the preceding claim, the use of a
reciprocating or revolving plug or slide H for effecting the periodical transmission
of the liquid, and a piston S for regulating the quantity so transmitted, substantially
as described.
Dated this 20th day of May 1892.
ABEL & IMRAI,
Agents for the Applicant.