Year: 1898

page_text: I, ARTHUR FREDERICK EVANS, of 11, Brunswick Walk, Cambridge, Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in screw propellers and has special
reference to means and devices for varying and reversing the pitch of said screw
propellers.
The object of this invention is to provide a means whereby, the blades of the
screw propeller are fitted into the boss in such a manner as that they are well sup-
ported in the boss and the blades can be readily removed or replaced without
disturbing any of the mechanism, and if required, the whole of the propeller can
be dismantled and removed by the simple process of unscrewing. Further, these
improvements relieve the shaft from any unusual strain's that may occur.
In carrying this invention into practice I use two, three, or more blades as may
be convenient. I provide a propeller boss fixed on to the propeller shaft and to the
stern post of the boat or vessel in the manner to be hereinafter described. This
boss is preferably cylindrical in shape and terminates at the outer or aft end in a
cone. Two or more recesses are provided according to the number of blades,
which recesses are turned in the boss at right angles to its axis, to a depth sufficient
to receive the stem of the propeller blade and at the inner end of each recess a
smaller hole is bored and fitted to receive the end of the stem aforesaid. The
bottom of each propeller blade has a collar or shoulder and terminates in a gudgeon
or stem, having at its end the neck hereinbefore mentioned. I provide a gland
which is screwed into the recess aforesaid which gland is bored out to receive
the said stem which revolves in it the said gland having a shoulder or flange
which rests on the surface of the boss.
The bottom of the said stem of the propeller blade is provided with a bush or
sleeve, firmly secured and fixed to the stem by a taper pin or otherwise. This
bush or sleeve is turned to exactly fit the space and is also deep enough to fit the
recess between the underside of the gland and the bottom of the recess so that the
upper and lower surface of the said bush or sleeve bears respectively against the gland
and the bottom of the recess. On the outside of the said bush or sleeve, grooves are
cut parallel to its axis, thus forming a pinion of the said bush or sleeve. This
pinion so formed is actuated by two rods which serve the purpose of racks in the
following manner: Two holes are bored in the boss parallel to its axis, and which
slightly intersect the circumference of the circle of the recesses aforesaid. Inserted
in these holes are rods, which are cut on one side to form a rack which engages
with the pinion, bush, or sleeve aforesaid. These two rods or racks
are secured to a lug or flange forming part of a sleeve or bush
which envelops the propeller shaft and is prolonged to the inside of the boat.
This sleeve or bush which of course revolves with the shaft is carried on bearings
in the usual manner and is actuated laterally by a reversing or regulating lever,
with a grooved sleeve and loose clamp, or any convenient means for controlling

page_text: and regulating the fore and aft motion of the bush or sleeve on the propeller shaft,
the effect of which is, that the racks engage the pinions and so cause the propeller
blades to revolve, and thus the pitch of the blades is altered or reversed as may be
required, as by this arrangement the blades can be rotated on their axes the whole
or any part of a circle so that any lateral movement of the sleeve on the propeller
shaft will cause the racks to revolve the pinions, and thus revolve the propeller
blades on their axes.
A stuffing box is provided inside the boat between the sleeve aforesaid and
the shaft to prevent the water getting into the boat or vessel.
The attachment of the propeller to the boat is effected in the following manner;--
On to the stern post of the vessel or other convenient fixture a flange or gland is
attached, having a long neck or sleeve on the outside of which a thread is cut.
This said flange or sleeve is bored out to receive sliding sleeve and propeller
shaft aforesaid. Screwed on to the out-side of this said neck or sleeve is a cylindrical
piece of metal, the inner screwed portion of which has an internal projecting
Hange, which forms with the outer end of the long neck or sleeve aforesaid, a
stuffing box, serving to prevent water from passing into the boat outside the shaft
sleeve aforesaid.
The after part of this cylinder is bored out to loosely fit the outside of the pro-
peller boss and envelopes the same as far as the propeller blades.
The propeller boss is screwed onto the propeller shaft, or it may be fixed thereto
in any other convenient manner. In the case of the boss being screwed to the
shaft I make the thread of the screw on the shaft left handed and that of the sleeve
right handed or vice-versa, to prevent any chance of the propeller becoming
detached.
111
1000
REGINALD W. BARKER,
Applicant's Agent,
Vulcan House, 56, Ludgate Hill, E.C.
I, ARTHUR FREDERICK EVANS, of 11, Brunswick Walk, Cambridge, Engineer,
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 follow-
ing statement:-
-
This invention relates to improvements in screw propellers and has special
reference to means and devices for varying and reversing the pitch of said screw
propellers.
The object of this invention is to provide a means whereby the blades of the
screw propeller are fitted into the boss in such a manner as that they are well sup-
ported in the boss and the blades can be readily removed or replaced without
disturbing any of the mechanism, and if required the whole of the propeller_can
be dismantled and removed by the simple process of unscrewing. Further, these
improvements relieve the shaft from any unusual strains that may occur.
In carrying this invention into practice I use two, three or more blades as may
be convenient. I provide a propeller boss fixed on to the propeller shaft and to the
stern post of the boat or vessel in the manner to be hereinafter described. This
boss is preferably cylindrical in shape and terminates at the outer or aft end in a
cone. Two or more recesses are provided according to the number of blades,
which recesses are turned in the boss at right angles to its axis, to a depth sufficient

page_text: to receive the stem of the propeller blade and at the inner end of each recess a
smaller hole is bored and fitted to receive the end of the stem aforesaid. The
bottom of each propeller blade has a collar or shoulder and terminates in a gudgeon
or stem, having at its end the neck herein before mentioned. I provide a gland
which is screwed into the recess aforesaid which gland is bored out to receive
the said stem which revolves in it the said gland having a shoulder or flange
which rests on the surface of the boss.
The bottom of the said stem of the propeller blade is provided with a bush or
sleeve, firmly secured and fixed to the stem by a taper pin or otherwise. This
bush or sleeve is turned to exactly fit the space and is also deep enough to fit the
recess between the underside of the gland and the bottom of the recess so that the
upper and lower surface of the said bush or sleeve bears respectively against the gland
and the bottom of the recess. On the outside of the said bush or sleeve, grooves are
cut parallel to its axis, thus forming a pinion of the said bush or sleeve. This
pinion so formed is actuated by two rods which serve the purpose of racks in the
following manner:-Two holes are bored in the boss parallel to its axis, and which
slightly intersect the circumference of the circle of the recesses aforesaid. Inserted
in these holes are rods, which are cut on one side to form a rack which engages
with the pinion bush or sleeve aforesaid. These two rods 01' racks
are secured to a lug or flange forming part of a sleeve от bush
which envelops the propeller shaft and is prolonged to the inside of the boat.
This sleeve or bush which of course revolves with the shaft is carried on bearings
in the usual manner and is actuated laterally by a reversing or regulating lever
with a grooved sleeve and loose clamp or any convenient means for controlling
and regulating the fore and aft motion of the bush or sleeve on the propeller shaft,
the effect of which is, that the racks engage the pinions and so cause the propeller
blades to revolve and thus the pitch of the blades is altered or reversed as may be
required, as by this arrangement the blades can be rotated on their axes the whole
or any part of a circle so that any lateral movement of the sleeve on the propeller
shaft will cause the racks to revolve the pinions and thus revolve the propeller
blades on their axes. A modification of this arrangement is preferably adopted
by means of a lever pivotted to the framework of the boat attached to the aforesaid
loose clamp and continued on to a handle and quadrant notched or otherwise. An
adjustable stop or clamp is provided on the shaft which will have the effect of
determining the amount of the pitch of the blades when the lever is placed full
ahead.
A stuffing box is provided inside the boat between the sleeve aforesaid and
the shaft to prevent the water from getting into the boat or vessel.
The attachment of the propeller to the boat is effected in the following manner;
On to the stern post of the vessel or other convenient fixture a flange or gland is
attached having a long neck or sleeve on the outside of which a thread is cut.
This said flange or sleeve is bored out to receive the sliding sleeve and propeller
shaft aforesaid. Screwed on to the outside of this said neck or sleeve is a cylindrical
piece of metal, the inner screwed portion of which has an internal projecting
flange, which forms with the outer end of the long neck or sleeve aforesaid. a
stuffing box, serving to prevent water from passing into the boat outside the shaft
sleeve aforesaid.
The after part of this cylinder is bored out to loosely fit the outside of the pro-
peller boss and envelopes the same as far as the propeller blades.
The propeller boss is screwed on to the propeller shaft, or it may be fixed thereto
in any other convenient manner. In the case of the boss being screwed to the
shaft I make the thread of the screw on the shaft left-handed and that of the
sleeve right-handed or vice versa, to prevent any chance of the propeller becoming
detached.
In order that this invention may be readily understood reference is made to the
accompanying drawings in which Fig. 1, represents a longitudinal section along
the line of the propeller shaft, Fig. 2 a cross section through the propeller, Fig. 3,

page_text: a cross section through the propeller shaft shewing the sleeve, rods and flange in
section, Fig. 4 is a sectional plan, shewing the rack and pinion arrangement for
adjusting the pitch or position of the propeller blades. In these several views A
is the propeller shaft, B the propeller boss screwed on the propeller shaft at C
D) is the sleeve sliding on the surface of the propeller shaft A terminating at the
propeller end with a lug or flange.E screwed or otherwise fixed to the said sleeve.
This said lug or flange has two rods F F projecting from it and which fit into
holes bored in the body of the propeller boss parallel to its axis.. G G are the
propellers which may be two, three or more in number as may be convenient.
Recesses H H are provided in the propeller boss B according to the number of
blades, and are turned or bored in the boss at right angles to its axis to a depth
sufficient to receive the stem L of the propeller blade. At the inner end of this
said recess, a further recess J is bored of a smaller diameter and fitted to receive
the end of the stem of the propeller blade. The bottom of each propeller blade
is provided with a collar or shoulder K and terminates in a gudgeon or stem L
reduced to fit the aforesaid recess J. M is a gland screwed into the aforesaid
recess H. N is a bush or sleeve turned to exactly fit the recess and fixed to the
stem of the propeller blade by a pin n. 0 are grooves cut parallel
to the axis of said bush forming it into a pinion. The rods F, F
are also cut on one side at P P to form a rack which engages with the
pinioned bush N. The propeller shaft A and sliding sleeve D revolves in the
bush or bearing Q which passes through the stern post R and is fixed to it by
bolts or screws through the flange S. T is a covering or supporting sleeve,
screwed on to the aforesaid bush Q which has a prolonged sleeve with hollowed
end to form a stuffing box or gland for keeping the water out of the boat or vessel.
W is a grooved sleeve screwed or keyed on to the sliding sleeve D on the propeller
shaft A, which sleeve is actuated and caused to move fore or aft by the lever X
and pins Y the said lever being pivotted to the framework of the boat or vessel
at %, a is an adjustable clamp of any convenient detail for regulating and con-
trolling the travel of the lever X and sliding sleeve W and consequently the amount
of the pitch of the propeller blades.
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. In screw propellers the provision of a means for automatically adjusting
or reversing the position of the propellers substantially as and for the purpose
herein set forth and described and illustrated by the accompanying drawings.
2. The application of this invention to any form or kind of screw propeller sub-
stantially as and for the purpose herein set forth and described and illustrated by
the accompanying drawings.
REGINALD W. BARKER,
Applicant's Agent,
Vulcan House, 56, Ludgate Hill, London, E.C..