IMPROVEMENTS IN VALVE- GEAR FOR MOTIVE-POWER ENGINES
Year: 1881

page_text: LETTERS PATENT to William Hargreaves and William Inglis, both of Bolton,
in the County of Lancaster, for an Invention of "IMPROVEMENTS IN VALVE-
GEAR FOR MOTIVE-POWER ENGINES."
PROVISIONAL SPECIFICATION left by the said William Hargreaves and
William Inglis at the Office of the Commissioners of Patents on the 5th July
1881.
WILLIAM HARGREAVES and WILLIAM INGLIS, both of Bolton, in the County of
Lancaster. "IMPROVEMENTS IN VALVE GEAR FOR MOTIVE-POWER ENGINES."
#
This Invention has for its object to improve the construction and action of valvo
gear for motive-power engines, and the improved gear is arranged to operate to a
certain extent, like what is known as Corliss valve gear, and is designed to act on
Corliss valves; parts of the improved gear are however also applicable for other
valves and gear.
The improved valve gear is applicable for engines with the cylinder or cylinders
in vertical or inclined positions, but is hereinafter described as arranged for one or
more horizontal cylinders. A horizontal valve-motion shaft driven by means of
bevil wheels from the crank shaft is carried at the side of the cylinder at the level
of, and parallel to, the cylinder's axis, and has cams fixed on it for opening the
admission valves. The admission valves are acted on by vertical rods arranged to
move vertically in guides, the valve-spindle levers being formed or fitted with
pins having on them square blocks, which have a slight transverse movement in
slots or grooves formed at the upper parts of the vertical rods. Below the slot each
vertical rod has adjustably fixed on it a block or boss fitted with a horizontal steel
engaging edge across the bottom at one side, and a corresponding steel engaging
piece is fixed upon a lever piece, which is jointed to a casting formed with a sleeve
or tube to slide on the vertical rod and with a horizontal arm, on the underside of
which it is that the cam on the valve-motion shaft acts. As the cam rotates it lifts
the sleeve piece, and the lever piece thereon being then in a suitable position, its
engaging piece engages with the engaging edge of the vertical rod, thereby lifting
Prine S1

page_text: this rod and by it opening the valve. The cam is shaped to keep the valve open
for a maximum period, and when the steam or motive fluid is to be cut off at an
earlier period in the stroke, a trigger acts on the lever piece so as to move its
engaging piece from under that of the vertical rod, whereupon the vertical rod
drops by its own weight, aided if necessary by a spring, and quickly closes the
valve. One object had in view in devising the improved valve gear is the opening
of the valve to its full extent, or nearly so, at a very early period of the stroke, so
that it may be well open even when the cut-off is made very carly, a result which
is not satisfactorily obtainable with ordinary Corliss valve gear. The cam is shaped
to open the valve quickly and fully, and then to keep it so open until the release
takes places, and a spring is applied if necessary to the sleeve piece to keep it with
its arm always in contact with the cam. The trigger is centered on the sleeve
piece, and it is connected by a rod to a lever piece on a shaft carried in stationary
bearings, and hereinafter termed the regulating shaft. The lever piece on the
regulating shaft receives a rocking motion by means of a rod from an eccentric on
the valve-motion shaft, and thereby causes the trigger to effect the release. The
regulating shaft is carried eccentrically in its bearings, and can be adjusted or moved
either by hand or by a speed governor so as to cause the cut-off to take place at
an carlier or later period of the stroke. When the cylinder is the low-pressure
cylinder of a compound engine, the cut-off is preferably arranged to be adjustable
by hand, but the valve gear of the high-pressure cylinder of a compound engine,
and that of the cylinder of a non-compound engine, may be arranged in connection
with a governor.
The usual dash-pot or cylinder for arresting the motion of the parts when closing
the admission valves is by preference placed at the bottom of the frame piece or
casting carrying the vertical rod and parts connected therewith, a piston being
fixed on the bottom end of the rod, and an adjustable valve or cock may be arranged
in the bottom of the cylinder to regulate the ingress and egress of air.
The exhaust valves of the engine may be worked from the valve-motion shaft in
various ways. In one modification short horizontal shafts at right angles to the
valve-motion shaft, and driven therefrom by bevil wheels, have cranks on their
outer ends, rods from which impart rocking motions to the valve spindles. In
other modifications eccentrics or cranks on the valve-motion shaft impart recipro-
cating movements to vertical slides, which act on the levers of the valve spindles
like the vertical rods acting on those of the admission valves. The eccentrics act
directly on the slides or through the intervention of bell-crank levers arranged to
produce a pause in the movement, so as to operate with a diminished extent of
motion of the valve.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Hargreaves and William Inglis in the Great Seal Patent
Office on the 31st December 1881.
WILLIAM HARGREAVES and WILLIAM INGLIS, both of Bolton, in the County of
Lancaster. "IMPROVEMENTS IN VALVE GEAR FOR MOTIVE-POWER ENGINES."
Our said Invention has for its object to improve the construction and action of
valve gear for motive-power engines; and our improved gear is arranged to operate
to a certain extent like what is known as Corliss valve gear, and it is designed to
act on Corliss valves.
Parts of our improved gear are however also applicable
for other valves and gear.
Our improved valve gear is applicable for engines with the cylinder or cylinders
in vertical or inclined positions, but is hereinafter described as arranged for one or
more horizontal cylinders according to two modifications which are shown on three
accompanying Sheets of explanatory Drawings.
Figures 1, 2, and 3, on Sheet 1, of the Drawings are a plan, a side elevation,
and a transverse vertical section of one modification of our improved valve gear;
and Figures 4 to 8, on Sheet 2, are enlarged detail views of the same modification,
Figures 9, 10, 11, on Sheet 3, are a horizontal section, a side elevation, and a
transverse vertical section of the second modification. In these Drawings the
same reference numerals are used to mark the same or like parts wherever they
are repeated.
In the modification shown on Sheets 1 and 2 of the Drawings a horizontal
valve-motion shaft 12, driven by means of bevil weeels from the crank shaft, is
carried at the side of the cylinder 13 at the level of and parallel to the cylinder's
axis, and has cams 14 fixed on it for opening the admission valves. The part of
the valve-motion shaft 12 near the cylinder 13 is carried in two hollow standards 15,
in and on which are also carried various parts of the valve gear. One of these
standards 15 is shown in vertical section in Figure 5, whilst Figure 4 is a section
of the upper part as taken at right angles to Figure 5. The admission valves,
which are supposed to be of the Corliss type but not shown in detail in the
Drawings, are placed, as usual with such valves, across the top of the cylinder,
their spindles 16 being horizontal and extending outwards to bearings 17 at
the upper part of the standards 15. The admission valve spindles 16
are acted on each by a vertical rod 18 arranged to move vertically in guides
in the top and bottom of the standard 15, each valve spindle having fixed
on it a lever 19 formed or fitted with a pin, having on it a square block 20
which has a slight transverse movement in a slot or groove formed across an
enlargement on the vertical rod 18. Below the slot each vertical rod 18 has
adjustably fixed on it a block or boss 21 fitted with a horizontal steel engaging
edge 22 across the bottom at one side, and a corresponding steel engaging piece 23
is fixed upon a lever piece 24 which is jointed to a casting 25 formed with a sleeve
or tube 26 to slide on the vertical rod 18. This casting 25 is also formed with a
horizontal arm 27, and it is on the underside of this arm that the cam 14 on the
valve-motion shaft 12 acts. As the cam 14 rotates it lifts the sleeve piece 25,
26, 27, and the lever piece 24 thereon being then in a suitable position (ensured
by means of a helical spring in a socket formed in the sleeve 26, the spring
pressing the lower part of the lever piece towards the cylinder), the engaging
piece 23 engages under the engaging edge 22 of the block 21 fixed on the vertical
rod 18 and causes this rod to be lifted and the valve to be opened by it. The
cam 14 is shaped to keep the valve open for a maximum period, and when the
steam or motive fluid is to be cut off at an earlier period of the stroke a trigger 28

page_text: acts on the lever piece 24 so as to move its engaging piece 23 from under that 22
of the vertical rod 18, whereupon the vortical rod drops by its own weight aided,
if necessary, by a spring 29, and quickly closes the valve.
One object had in view in devising our improved valve gear is the opening of
the valve to its full extent or nearly so at a very early period of the stroke, so
that it may be well open even when the cut-off is made very early, a result which
is not satisfactorily obtainable with ordinary Corliss valve gear. The cam 14 is
shaped to open the valve quickly and fully and then to keep it so open until the
release takes place, and a spring 30 is applied to the sleeve pieco 26 to keep it
with its arm 27 always in contact with the cam. The trigger 28 is centered on the
sleeve-piece casting 25, and it is connected by a rod 31 to a lever piece 32, 33, on a
shaft 34 carried in stationary bearings in the standards 15, and hereinafter termed
the regulating shaft. The lever piece is a tubular boss having oppositely directed
levers 32, 33, formed or fixed on its opposite ends, and receives a rocking motion
by means of a rod 35 from an eccentric on the valve-motion shaft 12, and thereby
causes the trigger 28 to effect the release. The parts of the regulating shaft 34 on
which the lever pieces 32, 33, are carried are formed eccentrically relatively to the
parts of the shaft held in the stationary bearings, in consequence of which a small
rocking or angular adjustment of this regulating shaft in its bearings alters the
action on the triggers 28 so as to cause the cut-off to take place at an earlier or
later period of the stroke. The regulating shaft 34 may be arranged to be adjusted
by hand, but it is represented as being connected to a speed governor 37,
the lower end of the governor rod being jointed to a lever 38 on the regulating
shaft, and indicated by dotted lines in Figures 1, 2, 6, and 7. Figure 8 is a side
view of a part of the regulating shaft 34, and showing the eccentric part on which
one of the lever pieces 32, 33, is centered. Figures 6 and 7 are transverse sections
showing the shaft 34 as set in two different positions by the governor, and with
the lever piece 32, 33, on it with the lower parts 33 supposed to be at the same
distance from the valve-motion shaft (12) in both Figures, but with the upper
part 32, in Figure 7, moved by the governor action nearer to the trigger (28) so
that the action on it of the eccentric on the valve-motion shaft will cause it to
move the trigger to the releasing point at a correspondingly earlier period in the
stroke.
When the cylinder is the low-pressure cylinder of a compound engine the cut-off
is preferably arranged to be adjustable by hand, but the valve gear of the high-
pressure cylinder of a compound engine and that of the cylinder of a non-compound
engine may be arranged in connection with a governor as described.
The usual dash-pot or cylinder 39 for arresting the motion of the parts when
closing the admission valves is by preference placed at the bottom of the standard 15,
a piston 40 being fixed on the bottom end of the vertical rod 18, and a check
valve 41 being fitted to the bottom of the cylinder 39 to adniit air when the rod
and piston rise. An adjustable valve or cock may be fitted to the cylinder 39 to
regulate the ingress and egress of the air.
The exhaust valves of the engine may be worked from the valve-motion shaft 12
in various ways. In the modification shown in Figures 1 to 5 eccentrics 42 on the
shaft act each on a lever piece 43 which is arranged to act in the manner of a
Corliss wrist plate, and which is connected by a rod 44 to a short vertical rod or
slide 45. Each rod or slide 45 which works in vertical guides is made to act on
the exhaust-valve spindle 46 by means of a cross slot, the spindle 46 having fixed
on it a lever 47 formed or fitted with a pin, on which there is a square block 48
working in the cross slot. The eccentrics 42 might be connected directly to the
vertical slides 45, but with the interposed lever or wrist pieces 43 a pausing or
lingering takes place in the movement so that it operates with a diminished extent
of motion of the valves.
Another modification of the parts for working the exhaust valves is shown on
Sheet 3 of the Drawings, and in it short horizontal shafts 49 at right angles to the
valve-motion shaft 12, and driven therefrom by bevil wheels 50 have cranks 51 on

page_text: their outer ends from which rods 52 are connected to levers 47 on the valve
spindles 46 so as to impart rocking motions thereto.
Having thus particularly described our said Invention and the manner of
performing the same, we have to state that we do not restrict ourselves to the
precise details herein described or delineated, but that what we believe to be novel
and original, and claim as the Invention secured to us by and in terms of the
hereinbefore in part recited Letters Patent is,-
1. The arranging or combining together of the parts of valve gear for working
the admission valves of motive-power engines, substantially in the improved
manner hereinbefore described.
2. The combination consisting of the rotating cam (14), the piece (25, 26, 27),
carrying the lever piece (24) and trigger (28), the block (21) with its engaging
edge on the rod (18) which acts on the valve spindle, and parts for moving the
trigger from the valve-motion shaft, the several parts being arranged and operating
substantially as hereinbefore described.
3. The combination of the regulating shaft (34) connected to a speed governor,
or made adjustable by hand, with the lever pieces (32, 33), by which the
triggers (28) are acted on, the parts being arranged and operating substantially as
hereinbefore described.
4. The arranging or combining together of the parts of valve gear for working
the exhaust valves of motive-power engines, substantially in the improved manner
herein before described with reference to Figures 1, 2, 3, and 5 of the accompanying
Drawings.
5. The arranging or combining together of the parts of valve gear for working
the exhaust valves of motive-power engines, substantially in the improved manner
herein before described with reference to Figures 9, 10, and 11 of the accompanying
Drawings.
In witness whereof, we, the said William Hargreaves and William Inglis,
have hereunto set our hands and seals, this Twenty-ninth day of
December, in the year of our Lord One thousand eight hundred and
eighty one
W. HARGREAVES.
WILLIAM INGLIS.
(L.S.)
(L.S.)