Improvements in Motors Driven by Steam or any other Elastic Fluid Pressure.
Year: 1897

page_text: [Communicated from abroad by BENOIT JOSEPH XAVIER GOSSELIN, of No. 22,
Boulevard Poissonniere, Paris, in the Republic of France, Engineer.]
Improvements in Motors Driven by Steam or any other Elastic
Fluid Pressure.
I, HENRY HARINGTON LEIGH, Assoc. M. Inst. C.E., Fel. Ch. Inst. P.A., F.I. Inst.,
practising as Phillips and Leigh, of No. 22, Southampton Buildings, Chancery
Lane, in the Administrative County of London, Engineer and Patent Agent, do
hereby declare the nature of this invention to be as follows:-
The present invention relates to improvements in steam motors, compressed air
motors, or motors driven by any other elastic fluid and creates a new system of
motors.
The problem that I have endeavoured to solve has been the simplification of the
working parts or mechanism of a high speed motor.
The apparatus which forms the object of the present invention is in principal
constituted as follows:-
An iron cylinder contains in its interior a piston working with a minimum of
friction. The cylinder has two lateral orifices being the inlet and exhaust ports
respectively. The former is in communication with the source of elastic fluid or
motive power and the latter with either a condenser or the open air.
In all the following descriptions I will suppose that this elastic fluid is steam
obtained from water under pressure, but is must be clearly understood that all
that will be said touching my apparatus as a steam motor will apply also to the
same apparatus driven by any other suitable elastic fluid whatsoever.
The piston head is elongated and has a longitudinal passage or hole which is
intersected at its bottom end by a transverse passage or hole the two forming
an in cross-section. The latter or transverse hole, coincides alternately with
the inlet and exhaust ports of the cylinder during each stroke.
Assuming the piston to be at the extreme limit of its backward stroke or at the
moment when it is about to commence its forward stroke: -the transverse passage
in the piston communicates with the inlet port and the steam is admitted at full
pressure; the piston advances and when the top edge of the transverse passage
in the piston has passed the bottom edge of the inlet port the supply of steam is
of course cut off. The steam admitted to the cylinder acts by expansion till
the moment when the bottom edge of the transverse passage of the piston coincides
with the top edge of the exhaust port in the cylinder, when of course the escape
commences and the piston arrives at the forward end of its stroke at the moment
when the escape is completely established. The escape continues till the moment
when the piston under the influence of the cinetic force commences its backward
stroke then the escape is cut off and the steam, which remains imprisoned in the
cylinder undergoes a compression which reaches its maximum when, on the piston

page_text: moving backward, the top edge of the transverse passage in the piston coincides
with the bottom edge of the inlet port in the cylinder. At this moment the steam
under pressure is again admitted to the cylinder and when the piston has returned
to the limit of its backward stroke, it will have again taken up the position from
which it started. This completes the cycle of events and the successive phases
just described are repeated at every stroke.
The quantity of steam admitted depends upon the value of the compression
produced in the cylinder, and this value may be varied and regulated by the
relative proportions given to the longitudinal passage of the piston and the space
left between the cylinder cover and the piston at the end of the backward stroke.
The practical arrangements by which this cycle may be realised without depart-
ing from the essence of my invention are obviously numerous; for instance, an
arrangement similar to that already described but with this difference that the
steam is admitted only by the transverse passage or cavity in the piston and by
the longitudinal passage therein; or the piston may be of the ordinary type and the
distribution made separately by an additional auxiliary cylinder and piston
coupled rigidly to the others, and the said auxiliary piston and cylinder may be
situated either at the end or side of the main cylinder. In the case of the
auxiliary cylinder being situated at the end of the main cylinder it would contain
both inlet and exhaust port, but in the case of the auxiliary cylinder being
integral with the side of the main cylinder the former would contain the inlet port
at the bottom of its cylinder and the latter the exhaust port at the top of its
cylinder.
Another instance following the same principle would be to extend the main
cylinder longitudinally so as to form another smaller cylinder and attach a second
piston to the head of the main piston so as to work in the second cylinder the
jacket the top of the second cylinder by a third cylinder placed crosswise. In
this case the inlet port would be made in the jacket cylinder into which the steam
would enter whence it would pass through holes or ports made in the top of the
second cylinder and so gain access to the main cylinder and act on the main piston.
Yet another instance might be as follows:-a small cylinder at the end of the
main cylinder has an orifice at the junction controlled by a lift valve, the inlet
port being in the small cylinder and the exhaust in the main cylinder so that on
the piston terminating its backward stroke the piston would come in contact with
and raise the valve for a certain time and on arriving at the end of its course, the
piston uncovers the exhaust port.
The above are the general diagrammatical arrangements which can be adopted
for the construction of my motor, but it is of course understood that for the
practical realisation of my invention recourse will be had to all the means in use
in connection with modern mechanical construction and which it is not necessary
to mention here, such for instance as packing rings for the pistons, cylindrical
tubes for forming the inlet and outlets for the steam and such like details.
It is also to be understood that I reserve the right to combine two or more such
motors and to couple them together in any way according to the requirements
of the case.
The advantages to be derived by using my invention are chiefly as follows:-
1st. A motor of extreme-simplicity and notably a reduction to the minimum of
the working parts or mechanism, the omission of eccentrics, slide valves, gearing,
cocks and the like.
2nd. Absolutely automatic in action and easily maintained steamtight, separate
steam inlets and outlets.
3rd. Very high efficiency; a most essential point in connection with low-power
motors.
4th. Very strong mechanism not easily put out of order.
5th. Silent running and high degree of angular velocity.
6th. Will work as well when run in either direction.
My motor may be applied in various ways. It is especially suitable for driving
་་་

page_text: apparatus running at high angular velocity, as for instance electric dynamos,
ventilator fans and drills.
Dated the 5th day of October 1897
Improvements in Motors Driven by Steam or any other Elastic
Fluid Pressure.
I, HENRY HARINGTON LEIGH, Assoc. M. Inst. C.E., Fel. Ch. Inst. P.A., F.I. Inst.,
practising as Phillips and Leigh, of No. 22, Southampton Buildings, Chancery
Lane, in the Administrative County of London, Engineer and Patent Agent, 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 present invention relates to improvements in motors driven by steam, com-
pressed air or other compressible medium, its main object being simplicity of
construction in general and especially by simplifying the governing organs to
permit the motor to run at high speeds.
The advantages attained by the present invention are:-
1. Utmost simplicity of the motor and reduction of the parts for the steam
distribution to the smallest possible extent, doing away with the eccentric, cogged
wheels, distributing cocks, etc.
2. The working is perfectly automatic and unfailing, and easily maintained.
Steam and exhaust ports are separate.
3. Friction losses reduced to a minimum and consequently wear and tear
reduced to a minimum.
4. Strong individual parts.
5. Noiseless action and considerable speed.
6. The direction of rotation is indifferent.
The applicability of the motor is manifold. It is specially adapted for driving
apparatuses which require to be driven at a high rate of speed to run economically,
as for instance dynamos, ventilators, boring and drilling machines, etc.
The following is a description of my invention with reference to the accom-
panying drawings:-
The figure represents my motor in longitudinal section.
The motor consists of the main cylinder A in which the solid piston H moves
gas-tight. Upon this cylinder there is secured a second cylinder F of smaller
diameter for the likewise solid governing piston G. The pistons H and G are
firmly connected by a rod K.
Openings a are provided in the cylinder F for the admission of the driving
medium, for instance high pressure steam (in every instance where the following
specification mentions steam, it should also be understood to comprise compressed
air or any other gaseous medium kept under pressure) whereas the exit of steam
takes place through openings a² in the working cylinder A. The openings a
and a are opened and closed for the steam inlet and outlet by the governing
piston G and working piston H respectively.
The position of the pistons shown illustrates the commencement of their forward
stroke, the steam entering between them through the opening a¹. The pistons
move downwards. The admission of steam continues until the lower edge of the
governing piston G corresponds with the lower edges of the steam ports at which
moment the steam is shut off. The steam confined in the cylinder now expands

page_text: until the upper edge of the working piston H covers the upper edges of the
openings a², when the exit begins. The exit of steam lasts until the piston on its
return travel, by virtue of the momentum of the fly-wheel, attains such position
that the piston H covers the exhaust ports a². From this moment no further exit
of steam can take place and the steam still enclosed in the cylinder is compressed
more and more until the lower edge of the governing piston G begins to uncover
the steam ports a¹. The steam is again permitted to enter between the cylinders
and the play or reciprocating movement of the piston, after the latter has attained
the end of its travel, repeats itself.
The amount of steam admitted at each stroke of the piston depends upon the
amount of compression of the steam which remained behind in the cylinder.
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. A single-acting motor driven by steam, compressed air or other gaseous
medium characterised by two solid pistons connected together, and moving in
separate cylinders of different diameters, one of which pistons during its travel,
directly opens and closes the steam ports and the other in like manner opens and
closes the exhaust ports, so that no valve gear is necessary or employed, substan-
tially as herein described and illustrated.
2. A single-acting motor driven by steam, compressed air or other gascous
medium constructed, operated and working substantially as herein described and
illustrated.