Improvements in the Valve and Governing Mechanism of Steam and other Fluid Pressure Engines
Year: 1889

page_text: Date of Application, 11th June, 1889
Complete Specification Left, 11th Mar., 1890-Accepted, 12th Apr., 1890
PROVISIONAL SPECIFICATION.
Improvements in the Valve and Governing Mechanism of Steam and
other Fluid Pressure Engines.
1, JOHN WILLIAM MELLING, of 11 Birkett Bank, Wigan, in the County of
Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention consists chiefly in an improved method of and means for working
or actuating the cut off or admission valves of steam or other fluid pressure engines
whereby the speed of the engine may be regulated and controlled by varying the
amount of steam or other fluid entering through the admission valve this valve being
under the control of a governor or other regulator.
In one arrangement by which I propose to accomplish this in cases where cut off
valves are carried on the main valve as for instance in the arrangement for which 1
obtained Letters Patent No. 13178 of 1887, I form on or otherwise attach to the main
slide valve a cylinder (or it might be two cylinders) in line with and between the
circular or other cut off valves in which cylinder I fit two pistons that are part of or
attached to the cut off valves the end of each piston farthest from its respective
valve works in a part of the cylinder that is open to the exhaust port of the main
valve the opposite end being always exposed to the pressure of the steam in the steam
chest consequently the pressure of the steam will always keep the piston and with it
the cut off valve pressed inwards as far as is allowed; this position is with the cut off
valve closed, and if not interfered with the cut off valves would remain closed but
to each cut off valve a spindle is connected and is by preference carried through a
stuffing box to the outside of the steam chest and is suitably guided; on each spindle
is formed a shoulder or a catch in such a way as that when the main valve and with
it the two cut off valves with their spindles are reciprocating the movement of the
cut off valves is arrested by means of the catches on the spindles coming into
contact with the pivoted triggers or latches on the stationary framing, the relative
positions of the catches and the pivoted triggers being such that the cut off
valves are caused to open before the main valve opens. Each catch is released by
mechanism that is under the control of the governor or adjusted by hand so that the
release takes place at that part of the stroke according to the requirements of the load;
when the catch is released the pressure of the steam on the unbalanced part of the
cut off valve closes it rapidly; in order to avoid severe shock when closing 1 prefer
to form a recess or space in the seat of the valve into which enters a flange on the
cut off valve in such a way as to enclose a small quantity of steam and this steam
only having limited means of escape will cushion the valve; but other convenient
means for the prevention of shock may be employed. Or in place of employing a
cylinder with pistons as described on the main valve I may fit a piston on each cut
off valve spindle to work in a cylinder on the steam chest; or I may enlarge the
valve spindle where it works through the stuffing box and so get sufficient area on
the spindle for the steam to act upon; or I may combine both arrangements on one
valve; or in place of steam pressure I may employ a spring or weight connected
with each valve spindle to close the valve.
The catches may be tripped or released by any suitable means but I prefer to
use in combination with this mechanism a shaft governor which will adjust and
control the position or throw of an eccentric or its equivalent which gives a recipro-
cating movement to a sliding shaped plate or plates that will when its or their full
parts are drawn under the catches release them and allow the piston spring or weight
that is in connection therewith to close the valve; this arrangement of governor and
trip mechanism may be applied to cut off or admission valves of other constructions.

page_text: The regulator may be an ordinary governor and the trip or release caused by the
movement of the main valve spindle or the trip movement may be taken from any
convenient part of the engine.
1030
H. B. BARLOW,
Agent.
COMPLETE SPECIFICATION.
Improvements in the Valve and Governing Mechanism of Steam and
other Fluid Pressure Engines.
I, JOHN WILLIAM MELLING, of 11 Birket Bank, Wigan, in the County of
Lancaster, Engineer, do hereby declare the nature of this said invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
My invention consists chiefly in an improved method of and means for working or
actuating the cut off or admission valves of steam or other fluid pressure engines
whereby the speed of the engine may be regulated and controlled by varying the
amount of steam or other fluid entering through the admission valve, this valve being
under the control of a governor or other regulator.
Figures 1, 2 and 3 of the accompanying Drawings illustrate one arrangement by
which I propose to accomplish my invention when applied to the arrangement of
cut off valves carried on the main valve for which I obtained Letters Patent No. 13178
of 1887.
In these views a designates the steam chest, b the main slide valve actuated by
the spindle c, d d and d' d' are the cut off valves fitted in and carried by the main
valve bas described in the Specification to my aforesaid Patent; e and e¹ are the
respective spindles of the cut off valves d d and d¹ d'; ff are the admission ports
and the exhaust port.
According to my present improvements I form on or otherwise attach to the main
slide valve ba cylinder h (or it might be two cylinders) in line with and between the
cut off valves d d and d¹ d. In the cylinder h I fit two pistons i i¹ that are part of or
attached to the cut off valves; the end of each piston farthest from its respective
valve works in a part of the cylinder h that is open by a passage g¹ to the exhaust
port g of the main valve b.
The opposite end of each piston being always exposed to the pressure of the steam
in the steam chest a the pressure of the steam will consequently always keep the
piston or and with it the cut off valve d d or d' d' pressed inwards as far as is
allowed.
The above position is with the cut off valve closed, and if not interfered with the
cut off valves d d, d' d¹ would remain closed; but to the cut off valves are connected
the spindles e e¹ respectively which pass through stuffing boxes ji to the outside of
the steam chest a. These spindles e el are suitably guided in pedestals & ¹ and on
each spindle is formed a shoulder or catch e" whereby, when the main valve band
with it the two cut off valves with their spindles e el are reciprocating, the movement
of the cut off valves is arrested by means of the catches e¹ on the spindles e el coming
into contact with triggers or latches pivoted on the pedestals k k', the relative
positions of the catches e" and the pivoted triggers 7 being such that the cut off
valves dd, d' d' are caused to open before the main valve opens. The catches ell
may be tripped or released by any suitable means either by a governor or by hand;
but the releasing mechanism shown consists of the shaped plate m secured on a
shaft m to which is secured an arm n¹ all actuated by an eccentric or equivalent
under the control of a shaft governor so that the release takes place at that part of the
stroke according to the requirements of the load, and when the catch el is released
the pressare of the steam on the unbalanced part of the cut off valve closes the latter
rapidly.

page_text: In order to avoid severe shock when closing I prefer to form a recess or space in
the seat of each valve into which enters a corresponding flange d" on the cut off valve
in such a way as to enclose a small quantity of steam and this steam only having
limited means of escape will-cushion the valve; but other convenient means for the
prevention of shock may be employed.
In place of employing a cylinder on the main valve with pistons as described
1 may fit a piston on each cut off valve spindle e e¹ to work in a cylinder on the steam
chest.
Or I may adopt the arrangement illustrated by Figures 4, 5, 6 and 7 in which one
i
pistoni is fitted in the cylinder on the main valve b while the other piston is
formed by an enlargement of the cut off valve spindle e' where it works through the
stuffing box j and so gets sufficient area on the spindle for the steam to act upon.
In these views another arrangement of mechanism is also shown for tripping the
pivoted triggers or latches and releasing the catches el on the cut off valve
spindles e et. The latches are both pivoted on one pedestal and are connected
by a coiled spring o which constantly tends to draw the free ends of the latches /
together. These ends of the latches bear upon a block p fixed upon the main valve
spindle c and in this block p is fitted a sliding frame q the outer surfaces of which
form wedge shaped or tapering striking surfaces for tripping the latches and
The sliding
releasing the catches e as the main valve spindle c reciprocates.
frame Y is connected by a rod q' to the governor so that any variation of speed
adjusts the position of the wedge shaped frame g and consequently regulates the
moment at which the latches will be tripped. Or the frame q may be adjusted by
hand instead of being regulated by the governor.
Another arrangement of trip mechanism is illustrated by Figures 8, 9 and 10 in
which the valves are shown arranged as in the preceding case, one piston i working in
a cylinder h on the main valve b and the other piston being formed by an enlarge-
ment of the cut off valve spindle e¹. In this instance the catches el instead of being
formed on the cut off valve spindles e e¹ consist of two hooks pivoted to the ends of
the spindles eel the lower catch ell being supported by a plate spring el fixed on
the spindle e. The triggers or latches are pivoted on a cross piece c' carried on the
main valve spindle c and they hold the catches ell and so prevent the cut off
valves dd, d d from closing until released by a sliding tapered blocks which is
mounted on a lever s¹ fulcrumed on an arm el carried by and moving with the cross
piece c'. The lever s¹ is connected by a rod s to an elbow levert which is pivoted
at to the bed plate or framing and receives a reciprocating motion through a rod t¹!
from any convenient part of the engine. It will thus be evident that the lever s' and
the taper blocks receive a reciprocating movement up and down and so the latter
releases the catches e¹¹ by tripping the latches 1. The position of the taper blocks on
the lever is adjusted and consequently the moment of tripping the latches
regulated by a rod u connected from the governor to the block s.
is
The last arrangement illustrated by Figures 11, 12 and 13 is particularly applicable
for vertical engines.
trip
In this case both the pistons are shown working through the stuffing boxes ; j'
and connected to the cut off valve spindles ee which are connected to their
respective valves by links v fulcrumed at v¹ on the main valve b. The mechanism
shown consists of the two catches e¹¹ pivoted to the ends of the pistons and held in
the positions shown in the Drawings by the plate springs e¹¹. The cut off valves are
opened by means of the double crank lever to connected by a rod w¹ to and operated by
an eccentric or equivalent.
In a suitable guide frame is mounted a sliding bar x controlled by a rod T¹
connected to an eccentric controlled by a shaft governor. This bar a at the required
moment acts upon and releases from the lever wone or other of the catches e" thereby
allowing the steam pressure acting upon the piston i or to close the corresponding
cut off valve.
The various arrangements of tripping mechanism herein shown and described may
be applied to forms of cut off valves other than those shown and again the tripping

page_text: mechanism shown on one arrangement may be applied to the valvular arrangement
shown on another. Although all the illustrations are shown as for engines with one
main valve for both ends of the cylinder the principle is equally applicable to cases
where there is a main and a cut off valve at each end of 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. The combination with the cut off or admission valves of a steam or other fluid
pressure engine, of means such as the pistons for enabling the fluid pressure to
close said valves when released by suitable tripping mechanism substantially as herein
set forth.
2. Arranging the trip mechanism in such manner that the movement of the main
valve spindle releases the cut off valves and allows the same to be closed sub-
stantially as herein described with reference to the arrangement illustrated by
Figures 4, 5, 6 and 7.
3. The combination with tripping mechanism for cut off valves, of a shaft governor
arranged to release said tripping mechanism and allow the cut off valves to be closed
by the steam or other fluid pressure substantially as herein set forth.
4. The several constructions combinations and arrangements of parts embodying
my improvements in the valve and governing mechanism of steam and other fluid
pressure engines substantially as herein described and as illustrated by the Drawings
annexed.
Dated this 10th day of March 1890
H. B. BARLOW,
17, St. Ann's Square, Manchester, Agent for Applicant.