IMPROVEMENTS IN PROPELLERS AND APPARATUS CONNECTED THEREWITH
Year: 1880

page_text: LETTERS PATENT to Edward Griffith Brewer, of 33, Chancery Lane, in the
County of Middlesex, for an Invention of "IMPROVEMENTS IN PROPELLERS
AND APPARATUS CONNECTED THEREWITH." A communication from abroad
by Richard Smith, of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Edward Griffith Brewer
at the Office of the Commissioners of Patents on the 20th November 1880.
EDWARD GRIFFITH BREWER, of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS IN PROPELLERS AND APPARATUS CONNECTED THEREWITH."
A communication from abroad by Richard Smith, of New York, United States
of America.
This Invention relates to that class of propellers in which a pair of hinged blades
are opened, to be forced against the water for propulsion and then closed, to be
drawn through the same without obstruction, preparatory to the next stroke. It has
more special relation to that form of propeller in which two reciprocating shafts
are used, one being connected to the hinge of the blades, and the other by means of
a cross-bar and connecting rods or links to the backs of said blades.
The former shaft is preferably hollow, and the latter slides within it. The
function of the inner shaft is to open and close the blades; the function of the outer
shaft is to move said blades back and forth in the water, and to aid in closing
them.
The chief object of the present Invention is to provide a means for backing the
vessel by combining and arranging the shafts and actuating mechanism in such
manner that the propeller will operate with equal readiness and efficiency in either
direction.
To this end the said shafts are constructed and combined so that each of them
operates to force the opened blades against the water, the one when the motion is
forward, the other in backing; they are also connected together in such manner
that neither can move longitudinally beyond a certain limit without communicating
similar motion to the other.

page_text: The Invention refers chiefly to the improvements above mentioned. It also
refers to the special construction, combination and arrangement of the devices
employed, as particularly set forth and hereafter explained.
Two cylinders are arranged side by side and provided respectively with pistons
on piston rods. To the outer end of one piston-rod is attached a tubular shaft,
which is provided with an enlarged portion near its rear end, and extends forward
in a line with its rod to a cross-head of hinged blades. This cross-head works in
suitable guideways, and is provided with a rigidly secured transverse sleeve,
through which the hinge-pintle of said blades passes. Accordingly, every forward
or backward motion of one piston causes a similar and equal motion of said blades.
The tubular shaft is provided at its forward end on top and at bottom with
longitudinal slots, which correspond to one another in position, and to another slot
length wise.
The other piston-rod carries at its outer end a rigid arm extending at right angles
through slot into enlarged portion or drum, where it is rigidly connected to a shaft
that reciprocates longitudinally within the tubular shaft. The forward end of this
inner shaft carries a rigid cross-piece which slides within slots. The ends of this
cross-bar, are pivotally connected to the rear ends of link-bars, the forward ends
of, which are pivoted to the backs of propelling blades. The slots allow sufficient
longitudinal motion of either shaft to open or close the blades before engaging with
and moving the other shaft. The pistons are allowed to travel nearly or quite the
entire length of their respective cylinders,
The operation of the foregoing devices is as follows:-When it is desired to
propel the vessel, steam or its equivalent is let into the cylinder, so as to drive
piston alternately backward and forward in the usual manner. Suppose the blades
to be at the outset in their foremost position and open. The rearward movement
of piston forces shaft backward, and drives the open blades against the water so as
to propel the vessel; the shaft accompanies this backward movement. When the
return stroke begins this shaft being freed from engagement remains idle until the
metal of the other shaft at the rear ends of the slots encounters the arm and cross-
piece. During this inaction of shaft, the draft of the outer shaft on the hinge-pintle
of blades inevitably causes said blades to close. The two shafts being once more
in engagement, then return together to the forward end of their travel. During
this motion the closed blades offer no resistance, as they slide edgewise through the
water. When the second rearward stroke begins, the arm and cross-piece are at
the rearward ends of the slots respectively, so that one shaft remains again inactive
until the outer shaft by its pressure on the hinge-pintle of blades causes said blades
to open. The metal of shaft at the forward ends of slots then again engages arm
and cross-piece, and the two shafts advanço as before.
When the vessel is to be backed the steam or its equivalent is let into one
cylinder so as to move piston backward and forward therein. Suppose the blades
to be as before in their foremost position and open. The rearward movement of
inner shaft will then be unaccompanied by that of the other shaft until blades are
closed by the pressure of the former shaft against the backs of said blades. Said
inner shaft then engages said outer shaft and carries it backward, the blades
remaining closed during the stroke. When the inner shaft is withdrawn the other
shaft remains stationary until the draft of shaft on the backs of blades opens them.
The two shafts then move forward together, drawing the open blades against the
water so as to cause a backward movement of the vessel.
By shifting the motive power from one shaft to the other the action of the
propeller may be instantly and very conveniently reversed. The cylinders
employed are preferably of equal capacity and power, and when they are thus
constructed the vessel can be driven forward or backward with equal speed.
The said shafts are provided with suitable intermediate packing.
The guide-
bar is made strong enough to act also as a brace for the blades when they are
pushed backward against the water. When they are drawn forward for backing
the ship the strain comes chiefly upon the link-bars, these are therefore preferably

page_text: made at least four in number and of very strong material. Their points of
attachment to said blades are near the outer edges thereof, so that both the draft
and bracing action may be applied to more advantage than if said blades sustained
a pressure of water outside of said attaching points."
It is obvious that the shifting of power from one piston to the other may be
effected in many ways, and therefore the inventor does not confine himself to
those hereinafter stated, though they have been found very convenient for the
purpose.
A steamn-chest is arranged above cylinders and divided by a horizontal partition
into two chambers, the upper one being the valve-chest.
Two ports or sets of ports afford cominunication from chamber to chamber
through said partition, and these are governed by a flat sliding valve which is of
sufficient size to cover one port or set of ports at a time. This valve is shifted
laterally by a lever from one port or set of ports to the other.
The lower chamber of steam-chest is divided longitudinally between these ports
or sets of ports by a vertical partition into two apartments, one of which commu-
nicates with each end of one cylinder, and the other with each end of the other
cylinder. By reason of the above connections the shifting of valve from one port
or set of ports to the other will suffice to cut off steam from one cylinder and allow
it. to pass into the other cylinder, or vice versa. Thus a single motion involving
scarcely any exercise of strength will suffice to back the vessel at any time or to
propel it again when it has backed far enough.
"
The steam is admitted to the cylinders through ports having "puppet" valves and
valve-seats, each of said valves being provided with a stem. There are also
exhaust ports near the ends of the said cylinders, which ports have " "puppet
valves, valve-seats, and valve-stems. They are separated from the live-stcam ports
by partitions.
The stems of the live steam valves are each connected at their upper ends to the
extremity of the lower and horizontal arm of a bell crank lever, one lever being
used for each stem. The pair of said levers which are at each end of the cylinders
turn on a horizontal pivot rod. Each exhaust-valve stem is similarly attached to
similarly arranged bell-crank levers which are mounted in like manner on said rods
or shafts.
All of these rods have their bearings in standards on top of the cylinders. The
upper arm of each bell-crank lever is connected by a rod to the corresponding arm
of the corresponding lever at the other end of the cylinder. Thus the live-steam
valves of each cylinder are coupled together, and the exhaust-steam valves of each
cylinder are coupled together. Owing to these connections as the valve at one end
of the rod rises and opens its port, that at the other end shuts down upon its
seat and closes its port. Each pair of valves thus connected acts independently of
the others. Each piston rod is provided with arms which act on the bell-crank
levers belonging to its cylinder so as to oscillate them and operate their valves
properly at regular intervals.
Instead of the aforesaid valves, levers, rods, other devices having the same
functions may be used. They are described only to show one means of operating
the pistons and piston rods as stated. The Invention lies chiefly in the propelling
and reversing devices first herein described. They too may be considerably modified
without departing from its scope or principle. For example, one shaft is described as
sliding within the other, but it would be possible to arrange two parallel shafts
with pin and slot or equivalent connection so as to effect the same result.
The construction shown herein is preferable however because it allows one shaft
to brace, guide, and shield the other, and because it ensures perfectly central and
even action on the blades of the propeller.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edwin Griffith Brewer in the Great Seal Patent Office on
the 20th May 1881.
EDWARD GRIFFITH BREWER, of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS IN PROPELLERS AND APPARATUS CONNECTED THEREWITH."
A communication from abroad by Richard Smith, of New York, United States
of America.
This Invention relates to that class of propellers in which a pair of hinged blades
are opened to be forced against the water for propulsion and then closed, to be
drawn through the same without obstruction preparatory to the next stroke. It
has more special relation to the form of propeller in which two reciprocating shafts
are used, one being connected to the hinge of the blades, and the other by means of
a cross bar and connecting rods or links to the backs of said blades. The former
shaft is preferably hollow and the latter slides within it. The function of the inner
shaft is to open and close the blades; the function of the outer shaft is to move
said blades back and forth in the water and to aid in closing them.
The chief object of the present Invention is to provide a means for backing the
vessel by combining and arranging the shafts and actuating mechanism in such
manner that the propeller will operate with equal readiness and efficiency in either
direction.
To this end the said shafts are constructed and combined, so that each of them
operates to force the opened blades against the water, the one when the motion is
forward, the other in backing; they are also connected together in such manner
that neither can move longitudinally beyond a certain limit without communicating
similar motion to the other.
The Invention refers chiefly to the improvements above mentioned and as
hereinafter more explicitly claimed. It also refers to the special construction,
combination, and arrangement of the devices employed, as particularly set forth the
and hereafter explained in in this Specification.
In the accompanying Drawings Figure 1 represents a top view of my mechanism
partly in horizontal section.
Figure 2 represents a side elevation of the same also partly in section, omitting
the greater portion of the cylinders.
Figure 3 represents a side elevation of the said cylinders shewing the steam chest
in longitudinal vertical section.
Figure 4 represents a cross section of the cylinders taken through the valves
thereof.
Figure 5 represents a plan view of the steam chest sbewing the valve and valve
seats within the same.
Figure 6 represents a cross section of the cylinders and steam chest.
Figure 7 represents a horizontal section taken through the lower compartment
of the steam chest and the other devices on the same horizontal plane.
Figure 8 represents a side view of the propeller as applied to a vessel, and
Figure 9 represents a plan view of the cylinder valves and operating rods.
A and B designate two cylinders, or it might be two pairs of cylinders on the
compound principle, arranged side by side and provided respectively with pistons a
and b on piston rods 'A' and B'. One of these cylinders is the main or driving
cylinder, and the other the reversing or backing cylinder. To the outer end of
piston rod A' is attached a tubular shaft C which is provided with an enlarged
portion C¹ near its rear end, and extends forward in a line with its rod A¹ to the
cross head G of hinged blades E, F. This cross head works in suitable guides or

page_text: guideways g shown in Figure 8, and is provided with a rigidly secured transverse
sleeve G, Figure 1, through which the hinge pintle of said blades passes.
Accordingly every forward or backward motion of piston a causes a similar and
equal motion of said blades. The tubular shaft C is provided at its forward end on
top and at bottom with longitudinal slots c', c, which correspond to one another
in position, and to another slot c lengthwise. The other piston rod B¹ carries at
its outer end a rigid arm b¹ extending at right angles through slots c into enlarged
portion or drum C', where it is rigidly connected to a shaft D that reciprocates
longitudinally within the tubular shaft C. The forward end of this inner shaft
carries a rigid cross piece D', which slides within slots c', c¹.
The ends of this
cross bar are pivotted to the rear ends of link bars d, d, the forward ends of which
are pivotted to the backs of the propelling blades E, F. The slots c³, c², allow
sufficient longitudinal motion of either shaft to open or close the blades E, F, before
engaging with and moving the other shaft. The pistons a, b, are allowed to travel
nearly or quite the entire length of their respective cylinders.
The rods of the two pistons being connected to a single folding propeller blade
as described, it is obvious that either cylinder may operate such blade at the
pleasure of the engineer, the other or passive piston and rod, whichever it may be,
whether going forward or backing, following and being carried along by the active
one after the opening or closing of the blades of the propeller.
The operation of the foregoing devices is as follows:-When it is desired to
propel the vessel steam or its equivalent is let into the cylinder A so as to drive
piston a alternately backward and forward in the usual manner. Suppose the
blades E, F, to be at the outset in their foremost position and open. The rearward
movement of piston a forces shaft C backward and drives the open blades E, F,
against the water so as to propel the vessel; shaft D accompanies this backward
movement. When the return stroke begins this shaft D being freed from engage-
ment remains idle until the metal of the other shaft Cat the rear ends of the
slots c, c', encounters the arm b¹ and cross piece D'. During this inaction of the
shaft D the draft of the outer shaft C on the hinge pintle of blades E, F, inevitably
causes said blades to close. The two shafts being once more in engagement then
return together to the forward end of their travel. During this motion the closed
When the
blades offer no resistance, as they slide edgewise through the water.
second rearward stroke begins the arm and cross piece D' are at the rearward
ends of respectively slots c and c¹, so that the shaft D remains again inactive until
the outer shaft C by its pressure on the hinge pintle of blades E, F, causes said
blades to open. The metal of shaft C at the forward ends of slots c, c', then again
engages the arm b¹ and cross piece D¹, and the two shafts advance as before. When
the vessel is to be backed the steam or its equivalent is let into cylinder B so as
to move the piston b backward and forward therein. Suppose the blades E, F, to
be as before in their foremost position and open the rearward movement of inner
shaft D will then be unaccompanied by that of shaft C until the blades E, F, are
closed by the pressure of the former shaft against the backs of the said blades. Said
inner shaft then engages said outer shaft and carries it backward, the blades
remaining closed during the stroke. When the inner shaft D is withdrawn the
other shaft C remains stationary until the draft of shaft D on the backs of the
blades E, F, opens them. The two shafts then move forward together, drawing the
open blades against the water, so as to cause a backward movement of the vessel.
By shifting the motive power from one shaft to the other (that is, by changing
the steam admission from one cylinder to the other) the action of the propeller
may be instantly and very conveniently reversed. The cylinders employed are
preferably of equal capacity and power, and when they are constructed thus the
vessel can be driven forward or backward with equal speed.
The said shafts are provided with suitable intermediate packing H. The guide
bar G is made strong enough to act also as a brace for the blades E, F, when they
are pushed backward against the water. When they are drawn forward for

page_text: backing the ship the strain comes chiefly upon the link bars d, d. These are
therefore preferably made at least four in number and of very strong material.
Their points of attachment to said blades are near the outer edges thereof, so that
both the draft and bracing action may be applied to more advantage than if
said blades sustained a pressure of water outside of said attaching points.
It is obvious that the shifting of power from one piston to the other may be
effected in many ways, and therefore the inventor does not confine himself to those
hereinafter stated, though they have been found very convenient for the purposes.
I, designates a steam chest which is arranged above cylinders A, B, and divided
by a horizontal partition I into two chambers J and J¹, Figure 3, the upper one J
being the valve chest.
Two ports or sets of portsj, j', afford communication from chamber to chamber
through said partition I, and these are governed by a flat sliding valve K, which
is of sufficient size to cover one port or set of ports at a time. This valve is
shifted laterally by a lever S from one port or set of ports to the other.
The lower chamber J of steam chest I is divided longitudinally between these
ports or sets of ports by a vertical partition K, Figure 7, into two compartments L,
L', one of which communicates with each end of cylinder A, and the other with each
end of cylinder B. By reason of the above connections the shifting of valve K
from one port or set of ports j, j, to the other will suffice to cut off the steam from
cylinder A and allow it to pass into cylinder B, or vice versa. Thus a single motion
involving scarcely any exercise of strength will suffice to back the vessel at any
time or to propel it again when it bas backed far enough.
The steam is admitted to the cylinders through ports having puppet valves
M, N, O, P, Fig. 9, and valve seats m, m, m, m, each of said valves being provided
with a stem m², n', o', p¹. There are also exhaust ports near the ends of the said
cylinders, which ports have puppet valves Q, R, S, T, valve seats q, q, q, q, and
valve stems q¹, ¹, s', t'. They are separated from the live steam ports by
partition Z.
The stems m', n, o, p, of the live steam valves are each connected at their upper
ends to the extremity of the lower and horizontal_arm m³ of a bell crank lever
W, W, W, W, one lever being used for each stem. The pair of said levers which
are at each end of the cylinders turn on a horizontal pivot rod Y or Y¹ Each
exhaust valve stem is similarly attached to similarly arranged bell crank levers
We, WI, W¹, W, which are mounted in like manner on said rods or shafts.
All these rods have their bearings in standards on top of the cylinders. The
upper arm of each bell crank lever is connected by a rod Z to the corresponding
arm of the corresponding lever at the other end of the cylinder. Thus the live
steam valves of each cylinder are coupled together, and the exhaust steam valves
of each cylinder are coupled together. Owing to these connections as the valve
at one end of a rod Z rises and opens its port, that at the other end shuts down
upon its seat and closes its port. Each pair of valves thus connected acts
independently of the other. Each piston rod is provided with arms which act
on the bell crank levers belonging to its cylinder so as to oscillate them and
operate their valves properly at regular intervals.
.
Instead of the aforesaid valves, levers, rods, or other devices having the same
functions may be used. They are illustrated and described here only to shew one
means of operating the pistons and piston rods, as stated. The Invention lies
chiefly in the propelling and reversing devices, first herein described. They too
may be considerably modified without departing from its scope or principle. For
example, the inventor has described one shaft as sliding within the other, but it
could be possible to arrange two parallel shafts with pin and slot or equivalent
connection, so as to effect the same result. The construction shown herein is
preferable, however because it allows one shaft to brace, guide, and shield the
other, and because it insures perfectly central and even action on the blades of the
propeller.

page_text: Having thus fully described this Invention as communicated to me, what I
claim as new and desire to secure by Letters Patent is,-
First. A propeller having a pair of hinged blades and devices for opening and
closing the same by positive pressure, said propeller being adapted to move the
vessel either forward or backward at will, substantially as set forth.
Second. In combination with a pair of hinged propelling blades a pair of inter-
locking longitudinally reciprocating shafts, said shafts operating to move said
blades while the latter are expanded either forward or backward at will, there
being a short slip movement between them sufficient to open or close the propeller
blades, while at other times the two rods with the propeller move together,
substantially as described.
Third. In combination with a pair of hinged propelling blades a pair of inter-
locking longitudinally reciprocating shafts, one of said shafts sliding within the
other, and said shafts operating to move said blades while the latter are expanded
either forward or backward at will and having a short slip movement, as and for
the purpose described.
Fourth. In combination with the hinged propeller blades E, F, the shaft D, and
link bars d, d, said link bars being attached to said blades near their outer edges,
substantially as and for the purposes set forth.
Fifth. In combination with hinged blades E, F, the cross head G serving to carry
guide and brace the said blades, as set forth.
Sixth. In combination with hinged blades E, F, and reciprocating shafts C, D, a
pair of cylinders and pistons or their equivalents, provided with devices for shifting
the power at will from the shaft that propels the vessel to the shaft that backs it
as set forth.
In witness whereof, I, the said Edward Griffith Brewer, have hereunto set
my hand and seal, this Nineteenth day of May, in the year of our Lord
One thousand eight hundred and eighty one.
E. G. BREWER. (L.S.)