IMPROVEMENTS IN ROTATING SLIDE VALVES
Year: 1881

page_text: LETTERS PATENT to Peter Brotherhood, of Compton Street, Clerkenwell, in
the County of Middlesex, for an Invention of "IMPROVEMENTS IN ROTATING
SLIDE VALVES."
|PROVISIONAL SPECIFICATION left by the said Peter Brotherhood at the
Office of the Commissioners of Patents on the 17th February 1881.
PETER BROTHERHOOD, of Compton Street, Clerkenwell, in the County of
Middlesex. "IMPROVEMENTS IN ROTATING SLIDE VALVES."
My Invention relates to the construction and arrangement of rotating valve to
alternate the admission and emission of working fluid for motive power engines,
particularly those having two or more cylinders, the chief object of my Invention
being to completely balance the valve in all directions, and thereby to avoid
unequal friction and wear. For this purpose I make the valve in the form of a
hollow ring of rectangular section, and fit it to revolve between two cheeks or faces
and upon two annular lips projecting from those faces into the inner circle of the
ring. In the centre of the cavity within those lips I mount a shaft, arms on
which project into notches in the interior periphery of the ring, these arms
constituting drivers which cause the ring to revolve without straining it in either
direction. The working fluid admitted to the space between the cheeks outside
the ring passes through an aperture in the external periphery of the ring, and from
the internal cavity of the ring it passes by apertures on opposite sides of the ring
into breeches passages by which it flows to the working cylinders. The exhaust
from these cylinders returning by the breeches passages enters the cavity of the
ring by side apertures, and passes thence by an aperture through its inner periphery
to the central cavity of the valve casing, and thence to the discharge. In order to
separate the fluid of supply from that of discharge a partition within the ring
divides its cavity into two compartments, the one having the external aperture for

page_text: admission of the supply, and the other having the internal aperture for emission
of discharge fluid. For the purpose of varying cut off I fit a cylindrical ring in
the valve casing outside the valve ring, and by means of a pinion or otherwise I
turn this ring so as to advance more or less an aperture through which the working
fluid can pass into the valve ring, so that as the latter rotates this passage is closed
sooner or later as the case may be. For the purpose of reversing the motion of the
engine the valve may be turned round its driving shaft so as to be more or less in
advance of the engine shaft by any of the known methods employed for that
purpose, as for example by an inclined or helical feather on the shaft. Also by
means of a separate slide or set of valves the supply and discharge passages may 1
be inverted.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Peter Brotherhood in the Great Seal Patent Office on the
16th August 1881.
PETER BROTHERHOOD, of Compton Terrace, Clerkenwell, in the County of
Middlesex. "IMPROVEMENTS IN ROTATING SLIDE VALVES."
My Invention relates to the construction and arrangement of rotating valves to
alternate the admission and emission of working fluid for motive power engines,
particularly those having two or more cylinders, the chief object of my Invention
being to completely balance the valve in all directions, and thereby to avoid unequal
friction and wear. For this purpose I make the valve in the form of a hollow ring
of rectangular section, and fit it to revolve between two cheeks or faces and upon
two annular lips projecting from those faces into the inner circle of the ring. In
the centre of the cavity within those lips I mount a shaft, arms on which project
into notches in the interior periphery of the ring, these arms constituting drivers
which cause the ring to revolve without straining it in either direction. The
working fluid admitted to the space between the cheeks outside the ring passes
through an aperture in the external periphery of the ring, and from the internal
cavity of the ring it passes by apertures on opposite sides of the ring into breeches
passages, by which it flows to the working cylinders. The exhaust from these
cylinders returning by the breeches passages enters the cavity of the ring by side
apertures, and passes thence by an aperture through its inner periphery to the
central cavity of the valve casing, and thence to the discharge. In order to separate
the fluid of supply from that of discharge a partition within the ring divides its
cavity into two compartments, the one having the external aperture for admission
of the supply, and the other having the internal aperture for emission of discharge
fluid. For the purpose of varying cut off I fit a cylindrical ring in the valve.
casing outside the valve ring, and by means of a pinion or otherwise I turn this
ring so as to advance more or less an aperture through which the working fluid can
pass into the valve ring so that as the latter rotates this passage is closed sooner or
later as the case may be. For the purpose of reversing the motion of the engine
the valve may be turned round its driving shaft so as to be more or less in advance
of the engine shaft by any of the known methods employed for that purpose, as,
for example, by an inclined or helical feather on the shaft; also by means of a
separate slide or set of valves the supply and discharge passages may be inverted.
On the accompanying Drawings Fig. 1 is a vertical section; Fig. 2, a section on
the line A, B, on a plane at right angles to that shewn in Fig. 1; and Fig. 3
(Sheet II.) is a section on C, D, shewing the valve box and passages with the valve
itself, and the means of driving it omitted. In these Figures the valve is shewn
as it would be applied to a three cylinder engine having three passages a arranged
uniformly around the valve box. The valve V is in the form of a hollow
cylindrical ring having its internal cavity divided into two parts s and d by
partitions v. To the cavity 8 there is an opening 81 through the outer
circumference of the ring, and from the cavity d there are openings d¹
through the inner circumference. From the cavity 8 there are openings 82 through
both sides of the ring, and from the cavity d there are also openings d² through
both sides. The ring is placed between two stationary cheeks c, c, fitting
accurately between them with its inner circumference bearing on a lip c¹ pro-
jecting inwards from each cheek. Through both the cheeks c, c, there are
openings c, c, opposite to one another, both of these openings communicating
in each case with one of the cylinder passages a. The working fluid supplied
by the pipe 8, and regulated, if desired, by a governor, as will hereafter be described,

page_text: flows by a passage s¹ to an annular cavity s³, completely surrounding the valve V,
and thence by the opening s¹ enters the cavity s of the valve. When by the
rotation of the valve the side openings 2 pass over a pair of the openings c², c², the
fluid flows by one of the passages a to one of the cylinders. The interior of the
ring communicates by two side passages D¹, D', with a discharge pipe D. When
by the rotation of the valve the side openings d² pass over a pair of the openings
c2, c², then fluid from one of the cylinders flows by one of the passages a into the
cavity d of the valve, thence to the middle space within the slide, and thence by
the passages D', D', to the discharge pipe D. The rotation of the valve is effected
by means of two arms b, b, on the central rotating shaft B, these arms entering
grooves in the interior circumference of the valve with sufficient freedom to avoid
straining the valve in any direction, and as all the pressures on the valve, external,
internal, and lateral, are equally distributed over its surfaces, there is no tendency
to unequal pressure, friction, or wear. I have shewn in Figs. 1 and 2 a regulating
valve R in the supply pipe worked by a governor, of which Fig. 4, Sheet II., shews
a front view, Fig. 5 being a section on the line E, F. This governor consists of
two weights g, g, fitted to slide radially within-a casing G attached to the shaft B.
These weights are notched to receive arms of two bell crank levers g', g', (Fig. 1)
the other arms of which. bear against a central sliding rod g². This rod is pressed
inwards by a lever g³, which is acted on by a spring g', and is connected at its
upper end to the regulating slide valve R. When the shaft B revolves with
excessive speed the weights g, g, are caused by increased centrifugal force to slide
outwards, and their bell cranks g', gl, moving the lever g³ in opposition to the
..spring g', the supply valve R is more or less closed, thus retarding the engine.
The vertical section, Fig. 6, and transverse section, on G, H, Fig. 7, shew a mode
of varying the cut off or expansion applied in combination with a rotating slide
valve V such as I have described. In this case the arms b, b, which act as drivers
to the valve V, are fitted on a part of the shaft B, which is shaped helically. The
shaft is swivel jointed at b¹ to a lever b², provided with a spring catch which can
engage in notches in a fixed are 63. On moving the lever 62 in the one direction or
the other the helically shaped part of the shaft B causes the slide V to turn partly
round, so that its lateral supply openings s² are caused to pass the openings.c², c²,
in the side cheeks at an earlier or later point in each revolution of the engine
shaft.
Although in what precedes I have described the working fluid as being supplied
to the space externally surrounding the rotating valve, and as being discharged
from the space within it, this arrangement may obviously be inverted, and in that
case, while the valve remains in the same position on its shaft, the direction of
motion of the engine will be reversed. Fig. 8 (Sheet I.) shews an arrangement for
effecting reversal of the engine by thus inverting the supply and discharge;
Fig. 9 (Sheet II.) is a cross section on L, M; Fig. 10, a cross section on N, O
and Figs. 11 and 12 are part longitudinal sections on P, Q, and Q, R, respectively;
Fig. 13 being a section of the valve V shewn separately. In this construction
there is attached to the valve case a cylinder L, containing two pistons p¹, p², con-
nected together and to a shaft Q, on which is cut a screw thread q, gearing with a
worm wheel M on a shaft m that passes through a stuffing box. The cylinder L
has through its side three sets of openings communicating respectively with three
annular cavities, N¹, N2, N3. The first cavity N¹ communicates by passages n'
with the central part D¹ of the valve box; the second cavity N2 communicates
with the supply pipe S; the third cavity N³ communicates by passages n³ with
the annular space S² surrounding the valve V; also the ends of the cylinder Leare
open to cavities N* communicating by passages n with the discharge pipe D.
When the pistons p', p², are in the position shewn in Fig. 8 they put the spaces
N', N2, in communication with each other, and. the space N³ with N'; consequently
the fluid supplied by S to N2 passes by N¹ and n¹ to the central part D¹ of the valve,
whilst from the space S² surrounding the valve fluid can pass by n³ and N³ to N*,
and thence to the discharge pipe D. If now the pistons p¹, p², were moved to the

page_text: right, putting N2 and N³ in communication with one another, and N¹ in communica-
tion with N, the fluid supplied by S to N2 would pass by N³ and n³ to the space S²
surrounding the valve, whilst from the central space D¹ of the valve fluid would
pass by n¹ and N¹ to N*, and thence by n to the discharge pipe D. As the shaft Q
revolves along with the axis B of the valve, the worm wheel M is also caused to
revolve. If however the rotation of this wheel were retarded or arrested by a
brake or stop applied to its shaft m, then the screw thread q acting on the retarded
or stationary teeth of M would cause the pistons p¹, p², to move so as to effect the
inversion of the passages, as above described, and so to reverse the engine.
Having thus described the nature of my Invention, and in what manner the
same is to be performed, I claim,—
First. The construction of rotating slide valve in the form of a hollow ring,
divided into two compartments, one having an opening in the outer periphery, and
the other having an opening in the inner periphery, and both having lateral
openings equal on each side corresponding with ports in side cheeks, between which
the valve revolves, the pressure on the valve in all directions being balanced,
substantially as herein described.
'
Second. The combination of a balanced rotating slide valve, of the kind referred
to in the preceding claim, with a governor having sliding weights mounted on the
spindle of the slide, and connected with a regulating valve, substantially as described
with reference to Figs. 1, 2, 4, and 5 of the accompanying Drawings.
Third. The combination of a balanced rotating slide valve, of the kind referred
to in the first claim, with a helically shaped sliding spindle and lever for varying
cut off, substantially as described with reference to Figs. and 7.
Fourth. The combination of a balanced rotating slide valve, of the kind referred
to in the first claim, with a reversing valve, substantially as described with reference
to Figs. 8 to 13 inclusive.
In witness whereof, I, the said Peter Brotherhood, have hereunto set my
hand and seal, this Thirtieth day of July, in the year of our Lord One
thousand eight hundred and eighty one.
PETER BROTHERHOOD. (L.S.)