Improvements in or connected with Condensing Apparatus for Steam Engines.
Year: 1889

page_text: Date of Application, 4th Dec., 1889
Complete Specification Left, 4th Sept., 1890-Accepted, 4th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in or connected with Condensing Apparatus for
Steam Engines.
I JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention which has been communi-
cated to me from abroad by Joseph Alexis Damey of 16 Avenue Rapp Paris in the
Republic of France Engineer to be as follows:-
In steam engines as heretofore usually arranged the air and feed pumps have the
same number of movements as the engine. Nevertheless in some cases air pumps
are employed which have a motion independent of the engine and for many years
air and feed pumps have been worked by a special and independent engine for
condensing the steam of high speed engines but these arrangements are not suitable
for small and medium works on account of the great expense involved in their
purchase and working and the space which they occupy. Moreover they are only fit
to be used with very powerful engines.
Now the present invention relates to a combination of means for effecting the
condensation by injection forming in combination a species of attachment or auxiliary
engine or machine of small volume requiring a slow motion only for the air and feed
pumps and enabling the maximum of useful effect to be obtained by the vacuum of
the condensation and admitting of being conveniently placed in proximity to the
engine.
Pumps with a reciprocating motion such as air and feed pumps never work well
when driven at high speeds say 90 strokes per minute and upwards their useful effect
being considerably diminished and the vacuum produced being far from producing the
maximum of useful effect.
According to this invention with a slow motion from 70 to 72 centimetres of
vacuum measured by a column of mercury can be readily obtained.
The motion can be transmitted to the crank shaft working the pumps by a belt and
pulleys or by toothed or friction gear or any other suitable mechanism obtaining the
required speed for the pumps.
The condenser may in the case of a semi portable engine for example be carried on
a bracket or shelf behind the chimney or it may be arranged over the boiler between
the fly wheel pulleys for example and does not require any special foundation.
With this condenser is combined an injector in connection with a condensation
indicator and a feed pump worked by the same shaft as the two air pump pistons
which are worked by connecting rods of special construction composed of two bars
attached at their upper ends to a head or block with bearings working on the crank
pin and formed with an eye at the lower end by which they are connected to the
piston of the pump. This arrangement effects a considerable economy of space.
The two air pump pistons are perforated and provided with a disc of flexible
material acting as a valve closing the perforations. The centre of the valve disc
coincides with the axis of the air pump cylinder. The suction valves are of similar
construction and communicate with the chamber in which the injection takes place.
The pistons being directly connected to the connecting rod hereinbefore described are
guided by a rod or stem working in suitable fixed guides.
It results from the improved combination―
(1) That the arrangement of the condenser enables the greatest possible amount of
vacuum to be obtained in steam engines even when working at very high speeds.
(2) Being separated from the engine and occupying little space the apparatus
occasions no inconvenience and may be worked by known or ordinary mechanism for
transmitting motion.

page_text: (3) It can be applied to existing engines or may be attached to a wall and requires
no special foundation.
(4) By reason of the simplicity of its construction and its small weight the cost of
the apparatus is relatively low.
Dated this 4th day of December 1889
COMPLETE SPECIFICATION.
Improvements in or connected with Condensing Apparatus for
Steam Engines.
1, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex,
Gentleman do hereby declare the nature of this invention (which has been communi-
cated to me from abroad by Joseph Alexis Damey of 16 Avenue Rapp, Paris in the
Republic of France, Engineer) and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
In steam engines as heretofore usually arranged the air and feed pump pistons
make the same number of movements or strokes as the engine pistons. Nevertheless
in some cases air pumps are employed which have a motion independent of the engine
and for many years certain air and feed pumps have been worked by a separate or
independent engine for condensing the steam of high speed engines but these
arrangements are not suitable for small and medium works on account of the great
expense involved in their purchase and working and the large space which they
occupy. Moreover, they are only suitable for very powerful steam engines. Now
the present invention relates to a combination of means for effecting the condensation
by injection forming a species of attachment or auxiliary apparatus of small volume
requiring a slow motion only for the air and feed pumps and enabling the maximum
of useful effect to be obtained by the vacuum of the condensation and also admitting
of being conveniently placed in proximity to the main engine.
Pumps with a reciprocating motion such as ordinary air and feed pumps never
work well when driven at high speeds exceeding 90 strokes per minute their useful
effect being in this case considerably diminished and the vacuum obtained being far
from producing the maximum of useful effect. According to this invention with a
slow motion a vacuum equivalent to from 70 to 72 centimetres of mercury can be
readily obtained.
The motion can be transmitted to the crank shaft working the pumps by a belt and
pulleys or by toothed or friction gear or any other suitable mechanism obtaining the
required reduced speed for the pumps.
And in order that the said invention may be fully understood I shall now proceed
more particularly to describe the same and for that purpose shall refer to the several
figures on the annexed sheets of drawings the same letters of reference indicating
corresponding parts in all the figures.
Figure 1 of the accompanying drawings represents in side elevation sufficient of a
portable engine and boiler to explain the invention.
Figure 2 illustrates the same in end elevation partly in section.
Figure 5 drawn to a large scale illustrates in vertical and part in horizontal section
the air pumps hereinafter described and
Figures 3 and 4 illustrate a detail in the construction of the feed water heating
tubes.
The engine is provided with a condenser H, and Figures 1 and 2 of the drawing
shew the small dimensions and limited space occupied by this condenser relatively to
the size of the engine.
The condenser H may in the case of a semi portable or portable engine for
example be carried on a bracket or shelf behind the chimney F or it may be
arranged over the boiler A between the fly wheels or pulleys for example and does
not require any special foundation.

page_text: In Figures 1 and 2, illustrating the general arrangement of the engine, A is the
boiler which may be advantageously supplied with feed water heating arrangements
according to the invention described in the Specification accompanying my application
for a Patent dated 3rd December 1889 No. 19418. The feed water pipes are heated
by the exhaust steam in the hollow bed plate of the engine G as described in the said
Specification the said pipes being connected by a pipe Z to the superheating pipes V
arranged in the side Hues and heated by the products of combustion from the fire
box B which pass from C to D in the boiler tubes and flow under a plate Y through
an opening K back to the front under a horizontal partition at M finally returning
through L to the opening N leading into the upper part of the smoke box and
passing into the chimney F. The tubes V are connected together at their ends by
U shaped junction pieces T secured by bails U (Figures 3 and 4) and may be covered
by a non-conducting jacket X. The draught in the chimney may be increased by
means of a fan supplying or exhausting air through an orifice O. The engine is
represented as being provided with travelling axles RS and with legs or supports PQ
on which it may be supported when employed as a semi portable engine. E is the
steam dome.
The air pumps of the condenser H according to the present invention are worked
by a crank shaft a driven at a slower speed than the engine shaft c by a belt and
pulleys b.
The cranks in the shaft a are set at an angle of 180 degrees and the speed of
this shaft is regulated in such a manner relatively to the engine that the air pump
pistons make about 90 pulsations per minute as the maximum speed.
With this condenser is combined an injector I in connection with a condensation
indicator (Figure 2) and a feed pump J worked by the shaft a.
The two air pump
pistons (one of which is shown at 4, Figure 5,) are worked by connecting rods of
special construction composed of two bars or rods 1, attached at their upper ends to a
crosshead or block 2 with bearings working on the cranks and formed with an eye 3
at the lower end by which they are connected to the piston 4 of the pump. This
arrangement effects a considerable economy of space.
The two air pump pistons 4 are perforated and provided with a disc 5 of flexible
material acting as a valve closing the perforations. The centre of this valve disc
coincides with the axis of the air pump cylinder. The suction valves 6 are of
similar construction and communicate with the chamber 10 in which the injection
takes place. The pistons being directly connected to the connecting rods 1 are guided
by a rod or stem 7 working in a fixed guide 8.
It results from the improved combination hereinbefore described-
(1) That the arrangement of the condenser enables the greatest possible amount
of vacuum to be obtained in steam engines even when working at very high
speeds.
(2) Being separated from the engine and occupying little space the apparatus
occasions no inconvenience and may be worked by any known or ordinary mechanism
for transmitting motion.
(3) The apparatus can be applied to existing engines and admits of being simply
attached to a wall and requires no special foundation.
(4) By reason of the simplicity of its construction and its small weight the cost
of the apparatus is relatively low.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In stationary, portable and semi portable steam engines rotating at any speed
but more particularly in engines rotating at high speeds, the employment of a small
auxiliary self-contained apparatus occupying a limited space only and composed
essentially of a condenser working by injection and two single acting air pumps
actuated by one and the same shaft having two cranks set at an angle of 180 degrees
and driven by the engine shaft by the intervention of a belt and pulleys, toothed or

page_text: friction gear or other equivalent mechanism reducing the motion sufficiently to
cause the pumps to make not more than about 90 pulsations per minute as a maximum
with the object of rendering the said pumps more efficient in their action substantially
as herein before described.
2. In combination with air pumps of condensers for steam engines the employ-
ment of speed reducing pulleys or other gear for transmitting motion froin the
engine shaft for the purpose of reducing the relative speed of the said pumps in
order to improve their action substantially as hereinbefore described.
3. In working the air pumps of the condensing apparatus according to this inven-
tion converting the circular motion of the cranked shaft a into a reciprocating
rectilinear motion by means of a connecting rod composed of two parallel rods or
bars rigidly connected to the same crosshead and capable of admitting between them
the guide of the piston rod to which the said reciprocating rectilinear motion
is to be imparted substantially as herein before described with reference to the
accompanying drawings.
4. The general combinations and arrangements of parts constituting the improve-
ments in or connected with the condensing apparatus for steam engines substantially
as hereinbefore described. .
Dated this Ath d...
1000
J. H. JOHNSON & Co.,
Agents.