Improvements in Valve Gear for Steam-engines.
Year: 1886

page_text: Date of Application, 4th Dec., 1886.
Complete Left, 3rd Sept., 1887.
Complete Accepted, 4th Oct., 1887.
PROVISIONAL SPECIFICATION.
Improvements in Valve Gear for Steam-engines.
We, HERBERT LINDLEY and THOMAS BROWETT, both of Sandon Engine Works
St. Simon Street Salford in the County of Lancaster, Engineers, do hereby declare the
nature of this invention to be as follows:-
The object of this invention is to provide a better means of attaching circular or
cylindrical slide valves, such as are used in Rider and Corliss valve gears, to their
spindles, and consists in means whereby such valves can be rotated about their axes
(such rotary motion being imparted in any usual way to the valve spindles) and
also whereby it is possible for the valve to have a lateral motion in any direction at
right angles to the axis of the valve and spindle without producing a strain on the
spindle. For instance, in a Rider valve gear, as the main valve wears and gradually
advances towards the valve face, the cylindrical cut-off valve contained in the
cylindrical recess in the back of such main valve, must travel or move with it, and
therefore become eccentric to its spindle, and the object of this invention is to provide
a means whereby rotary motion can still be imparted to such a cut off valve, by its
spindle, and yet the spindle be free from all side strain due to eccentricity of the
cut off valve, which side strain would tend to lift the cut-off valve from its face, and
be otherwise detrimental. We are aware that hitherto each Rider & Corliss valve
has been mounted on a feather or flat plate formed on the valve spindle or secured
thereto in some manner, with the object that a valve so mounted can slide on this
feather or flat plate to compensate for wear, but such sliding of the valve can only
take place when the plane of the feather or plate is pointing in the direction of the
T
T
.
077

page_text: wear that has taken place, which in a Rider gear is usually towards the main valve
face or slightly inclined downwards. But as the valve is constantly rotating, it
follows that when the feather or plate is twisted into a fresh position and one in
which its plane does not coincide with the direction of the wear that has taken place,
there must be a binding and strain on the spindle which is in fixed hearings, and such
strain tends to lift the valve off its face and to cause general wear and tear of the
spindle in its glands or bearings and where it is attached to the valve.
The method that we employ for securing such afore-mentioned valve, such as the
cut-off valve of a Rider gear to its spindle, and which allows the valve to move in any
direction at right angles to the spindle without producing a strain thereon, and which
still ensures a perfect attachment or connection as far as twisting is concerned, is as
follows :-
To the spindle which actuates the cut off valve, and which passes right through the
same, is secured a small face plate or disc, with a rectangular groove cut diametrically
across its face.
A facing in which a similar groove is cut, is cast on the cut off valve, but the
groove in the cut-off valve facing is at right angles to the groove in the disc attached
to the spindle.
Between these two faces which are in parallel planes is a loose disc or plate, made
preferably of brass to avoid corrosion, and having on each of its two flat faces, a fillet
or key, that takes into the grooves made respectively in the disc and facing
aforementioned, such fillets or keys being therefore necessarily at right angles to
each other.
A small plate but without grooves (though the grooves and loose plate may
be repeated if desired) is secured to the valve spindle at the other end of the boss of
the cut off valve, which is thus confined as regards longitudinal motion & can
therefore be caused to slide or travel longitudinally by its spindle, whereas the
arrangement of plates with right angled grooves and fillets, which of itself forms the
imechanism known as "Oldhams coupling" serves to twist the valve about its axis,
even though eccentric to the spindle."
The distance apart of the extreme plates may be conveniently kept by the use of
a tube over the spindle slightly longer than the distance between them when all
close up together, the valve is thus ensured against jamming and the whole can be
securely bound together (leaving the valve free) by means of another tube slipped
over the valve spindle (which passes out of the valve chest at the back end) and
a nut on the other end of the spindle screwed against the outer end of the tube.
Dated 2nd of December 1886.

page_text: We HERBERT LINDLEY, and THOMAS BROWETT, both of Sandon Engine Works,
St. Simon Street, Salford in the County of Lancaster, Engineers 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 object of this invention is to provide a better means of attaching circular or
cylindrical slide valves, such as are used in Rider, and Corliss valve gears to their
spindles and consists in means whereby such valves can be rotated about their axes
(such rotary motion being imparted in any usual way to the valve spindles) and also
whereby it is possible for the valve to have a lateral motion in any direction at right
angles to the axis of the valve and spindle without producing a strain on the spindle.
For instance, in a Rider valve gear, as the main valve wears, and gradually advances
towards the valve face, the cylindrical cut-off valve contained in the cylindrical
recess in the back of such main valve, must travel or move with it, and therefore
become eccentric to its spindle, and the object of this invention is to provide a means
whereby rotary motion can still be imparted to such a cut-off valve, by its spindle,
and yet the spindle be free from all side strain due to eccentricity of the cut-off valve,
which side strain would tend to lift the cut-off valve from its face, and be otherwise
detrimental.
We are aware that hitherto such Rider, and Corliss valves have been mounted on a
feather or flat plate formed on the valve spindle or secured thereto in some manner,
with the object that a valve so mounted can slide on this feather or flat plate to
compensate for wear, but such sliding of the valve can only take place when the plane
of the feather or plate is pointing in the direction of the wear that has taken place,
which in a Rider gear is usually towards the main valve face or slightly inclined
downwards.
But as the valve is constantly rotating, it follows that when the feather or plate is
twisted into a fresh position and one in which its plane does not coincide with the
direction of the wear that has taken place, there must be a binding and strain on the
spindle which is in fixed bearings, and such strain tends to lift the valve off its face
and to cause general wear and tear of the spindle in its glands or bearings and where
it is attached to the valve.
The method that we employ for securing such afore-mentioned valve, such as the

page_text: cut off valve of a Rider gear, to its spindle, and which allows the valve to move in
any direction at right angles to the spindle without producing a strain thereon, and
which still ensures a perfect attachment or connection as far as twisting is concerned,
is as follows:-
To the spindle which actuates the cut off valve, and which passes right through the
same, is secured a small face plate or disc, with a rectangular groove, cut diametrically
across its face.
A facing in which a similar groove is cut, is cast on the cut-off valve, but the
groove in the cut-off valve facing is at right angles to the groove in the disc attached
to the spindle.
Between these two faces which are in parallel planes is a loose disc or plate, inade
preferably of brass, to avoid corrosion, and having on each of its two flat faces, a fillet
key, that takes into the grooves made respectively in the disc and facing afore-
mentioned, such fillets or keys being therefore necessarily at right angles to
each other.
ог
A small plate but without grooves (though the grooves and loose plate may be
repeated if desired) is secured to the valve spindle at the other end of the boss of the
cut off valve, which is thus confined as regards longitudinal motion and can therefore
be caused to slide or travel longitudinally by its spindle, whereas the arrangement of
plates with right angled grooves and fillets, which of itself forms the mechanism
known as "Oldham coupling
serves to twist the valve about its axis, even though
eccentric to the spindle.
"
The distance apart of the extreme plate may be conveniently kept by the use of a
tube over the spindle slightly longer than the distance between them when all close up
together, the valve is thus ensured against jamming and the whole can be securely
bound together (leaving the valve free) by means of another tube slipped over the
valve spindle (which passes out of the valve chest at the back end) and a nut on the
other end of the spindle screwed against the outer end of the tube.
And in order that our invention may be better understood we have caused to be
appended hereunto one sheet of drawings marked with letters of reference similar
letters indicating like parts throughout the various figures.
Fig. 1 is a side view and Fig. 2 an end view of a pair of Rider valves,
i.e. main & cut-off.
a is the main valve having a flat face with parts to slide against the flat valve face
of the cylinder. It contains also the cylindrical face in which slides the cylindrical
cut-off valve b. As is well known, in a Rider valve gear the cut-off edges of the
cut off valve are inclined, or portions respectively of a right and left hand spiral so
that if such a valve were opened out or developed onto a flat surface it would form an
inclined or wedge-shaped figure.
The rotation of this valve therefore causes it to correspond to a valve of variable
length according to the amount of taper and the amount of rotation given to it.
e is the spindle by which it is rotated and which also serves to move or traverse the
valve longitudinally.
Both these functions are performed by means of the plates d, e, f. The plate d is
keyed or cottered to the spindle and has a groovey on its face, shown more clearly
in Fig. 3.
Plate e is loose on the spindle and retained in position solely by the two fillets as
shown in Fig. 3, & which are at a right angle to each other, one fillet taking into the
groove g on plate d, and the other into the groove h on a face formed on the boss of
the cut-off valve.
The third plate is merely secured to the spindle as previously described, by means
of a tube on the spindle and a nut on the outside of valve chest, or merely cottered
thereto as shown in the drawing, care being taken by means of a distance tube or other
means, not to bind the cut-off valve, but to have it free to slide, in any direction at
right anglos to the axis of the spindle.
The system of plates with right angle grooves forms a previously mentioned

page_text: mechanism, known as Oldham coupling, & allows perfect freedom of motion in any
lateral direction at right angles to the spindle within certain limits, while still being
under control as far as any twisting or rotation is concerned.
Fig. 3 shows the cut-off valve with plates and distance tube, threaded on spindle
separated one from the other, and figured as before wherein the relation of the various
parts to each other is more clearly seen.
An exactly similar method of construction may be used in securing a Corliss valve
to its spindle, or the twisting plates may be repeated at the other end of valve so as to
impart the rotary motion from both ends of the valve.
Having now particularly described and ascertained the nature of our invention
and in what manner the same is to be performed, we declare that what we claim is :-
The use of a pair or pairs of keys, fillets, or slides at right angles to each other
either formed on circular plates or otherwise for the purpose of transmitting rotary
motion from a shaft or spindle to a cylindrical valve or any more modification thereof,
substantially as set forth and described and illustrated by the drawing.
Dain thin and dox of Santambar 1887
HERBERT LINDLEY.
THOMAS BROWETT.
By F. Bosshardt & Co.,
4, Corporation Street, Manchester,
Agents to Applicants.