IMPROVEMENTS IN HIGH-SPEED MOTORS ACTUATED BY STEAM OR OTHER FLUID
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I, ANDREW BETTS BROWN, of Rosebank Iron Works, Edinburgh, in the County
of Mid Lothian, North Britain, Engineer, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN HIGH-SPEED MOTORS ACTUATED BY STEAM OR
OTHER FLUID," to be as follows that is to say:
My said Invention relates to high-speed motors of the kind described in the
Specification of my Patent No 4912 of 1884, and comprises certain improvements
in details.
In motors of the kind referred to, four or other convenient number of single-
acting cylinders are carried so as to turn with the main shaft and their pistons are
connected to a stationary pin or crank placed occentrically to the axis of the main
shaft, the steam or other motive fluid being admitted to the outer ends of the
cylinders.
As described in my former Specification the connecting rods of the pistons had
separate bearings upon the stationary eccentric pin; and one of my improvements
consists in applying a single bearing or tube on this pin and connecting the several
connecting rods to it by joints excepting one which is by preference rigidly fixed
to it. The bearing surface of the stationary eccentric pin is made convex or of
other form having a smaller diameter at the ends, and the bearing which is made
in halves bolted together, is formed with contracted parts fitting the smaller parts
of the pin. The lubricant is supplied by a passage through the pin, and the form
of the bearing causes it to be retained in the lower part as in a reservoir, the
internal surface of the bearing being continually washed by the lubricant as it
rotates. The stationary eccentric pin instead of being overhung is formed with
a second journal or concentric pin at its inner end which is supported in a bearing
on the casting carrying the cylinders and turning with the main shaft.
The valve rods, with the bearing on their eccentric or eccentric pin are arranged
like the piston connecting rods and their bearing; and instead of the valves being
arranged to exhaust towards the centre, they are made to exhaust in an outward.
direction so that any water of condensation may be thrown from the cylinders by

page_text: centrifugal action. Each valve is formed with two pistons the steam being
admitted to the space between them. The openings in the cylinders which are
uncovered to the interiors when the pistons are at the inner ends of their strokes,
are put in communication with each other by a passage formed in the casting
carrying the cylinders so that when steam exhausts from one cylinder it passes
through the passage into the inner end of the opposite cylinder and causes any
water in the passage or cylinder to be blown towards the bearing of the stationary
eccentric pin. When the motor is running at a high speed the water thrown in
this way upon the bearing will tend to prevent overheating,

page_text: COMPLETE SPECIFICATION.
I, ANDREW BETTS BROWN, of Rosebank Iron Works, Edinburgh, in the County
of Mid Lothian, North Britain, Engineer, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN HIGH-SPEED MOTORS ACTUATED BY STEAM OR
OTHER FLUID" and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement that is
to say:
My said Invention relates to high-speed motors of the kind described in the
Specification of my Patent N° 4912 of 1884; and comprises certain improvements
in details.
A high-speed motor as made with my presont improvements is shown on two
accompanying sheets of explanatory drawings, figure, 1, on sheet, 1, being a
vertical section in the plane of the shaft, and figure, 2, on sheet, 2, a vertical section
as at right angles to the shaft, whilst figure, 3, is a similar view of parts supposed
to be removed in figure, 2. In these drawings the same reference numerals are
used to mark the same or like parts wherever they are repeated.--
In motors of the kind referred to, four (or other convenient number of) single-
acting cylinders, 4, are carried so as to turn with the main shaft, 5, and their
pistons, 6, are connected to a stationary pin or crank, 7, placed eccentrically to the
axis of the main shaft, 5, the steam or other motive fluid being admitted to the
outer ends of the cylinders, 4. Various parts of the motor which are not herein-
after described are constructed and arranged substantially like the corresponding
parts of the motor delineated and described in my earlier Specification herein before
referred to.
As described in my said earlier Specification the connecting rods, 8, of the
pistons, 6, had separate bearings upon the stationary crank pin, 7; and one of my
present improvements consists in applying a single bearing or tube, 9, on this pin
and connecting the several connecting rods, 8, to it by joints, 10, excepting one, 8¹,
which is rigidly fixed to it. This tube or bearing piece, 9; is made in two parts
which are bolted together the division between the two parts being arranged so as
also to divide the parts enclosing two of the joint pins, 10, whilst the third
joint pin, 10, (the uppermost when the parts are in the positions in which they
are shown in the drawings) is entered into its place by being inserted in a
direction parallel to the eccentric pin, 7. There is a comparatively slight
oscillating motion on the joint pins, 10, whilst the pressure of the tube or bearing
piece, 9, on the eccentric pin, 7, is a resultant of the varying pressures to the
several pistons, 6, and causes less friction upon the eccentric pin than that which
would be caused by separate bearings for the several connecting rods. The bearing
surface of the stationary eccentric pin, 7, is made convex or of other form having a
smaller diameter at the ends, and the bearing tube, 9, which as already mentioned,
is made in two parts bolted together, is formed with contracted parts fitting the
smaller parts of the pin, 7. In the drawings the pin, 7, is represented as having its
main part parallel or cylindrical whilst narrow reductions in diameter are formed

page_text: at its ends. The lubricant is supplied by a passage through the pin, 7, and the
form of the bearing surfaces causes it to be retained in the lower part as in a
reservoir the internal surface of the bearing tube, 9, being continually washed
by the lubricant as it rotates.
The stationary eccentric pin, 7, instead of being overhung is formed with a
second crank cheek, 11, and with a second journal or concentric pin, 12, at its
inner end, which journal, 12, is supported in a bearing, 13, formed on a casting, 14,
which partly carries the cylinders, 4, and connects them to the shaft, 5, and which
is formed with passages by which the steam or motive fluid has access to the valve
casings, 15, of the cylinders.
The valve connecting rods, 16, with the bearing piece, 17, on the eccentric, 18,
which is formed between the inner crank cheek, 11, of the main eccentric pin, 7,
and the inner journal, 12, are arranged like the piston connecting rods, 8, and their
bearing pieco, 9; but the parts are simplified by connecting the valves of each
diametrical pair by frames, 19, so that only two connecting rods, 16, are required
instead of four.
Instead of the valves, 20, being arranged to exhaust towards the centre, they
are made to exhaust in an outward direction, so that any water of condensation
may be thrown from the cylinders, 4, and valve casings, 15, by centrifugal action.
Each valve, 20, is formed with two pistons the steam or motive fluid being.admitted
to the space between them from the passages in the casting, 14.
The openings, 21, in the cylinders, 4, which are uncovered to the interiors when
the pistons, 6, are at the inner ends of their strokes may be put in communication
with each other from each cylinder to the diametrically opposite one, by a passage
or passages formed in the casting carrying the cylinders, so that when steam
exhausts from one cylinder it passes through the passage into the opposite cylinder
on the side of its piston nearest the centre and causes any water in the passage or
cylinder to be blown towards the bearing of the stationary eccentric pin, 7. When
the motor is running at a high speed the water thrown in this way upon the
bearing will tend to prevent overheating.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1-In motors having rotating cylinders, the connecting of the several pistons to
a single tube or bearing piece on the stationary eccentric pin, substantially as
herein before described.
2-In motors having rotating cylinders the connecting of the several valves to a
single tube or bearing piece on the eccentric or eccentric pin, substantially as
herein before described.
3-In motors having rotating cylinders the arranging of the valve casings and
valves so as to exhaust at the outer ends of the valve casings substantially as
herein before described.
Dated this twenty-fifth day of June 1885
EDMUND HUNT,
Applicant's Agent.