Year: 1885

page_text: I, ROBERT THOMAS BELLS of 42 Windsor Street Birkenhead in the County
of Chester Engineer do hereby declare the nature of this invention to be as
follows:-
This invention has for its object improvements in feathering apparatus for screw
propellers of the type described in my provisional specification No. 8493 of 1883,
and in Mr Bevis' specification No 684 of 1869, and is designed largely with the
object of adapting these inventions to cases where three or four blades are desired
and making the same adjustable when worn without enlarging the boss beyond the
size of the ordinary Bevis boss, used by Governinent which will only accommodate
two blades and these not adjustable when worn.
The improvements consist:
1st. In forming the shank of the blade and its bearing extra thick conical, so
that as it wears, the bearing can be adjusted, and turning out a recess in the said
increased thickness to accommodate packing rings as hereafter described.
.
2nd. In cutting out an annular slot in the bearing opposite the annular recess
in the shank for the cotter to slide in and in this slot placing two packing rings
held together by screws and having a bearing on a similar annular recess cut in
the shank. These packing, rings also have bearings on the cotter at both sides.
The two parts of the bearing on opposite sides of the slot are held together by
solid flanges beyond the slot. These also hold in the rings, consequently the
blade is kept in place not merely by the cotter, but also in case of accident to the
cotter, by the packing rings bearing both on the bearing slot and boss recess.
The hold on the shank is tightened up as it becomes slack by filing or turning off
a little from the lower ring and putting in a lining between the two rings thus
again forming a firm bearing on the blade shank and on both sides of the slot in
the bearing (above and below).
In my experimental model there are two rings. The bottom one bears on the
shoulder of the blade shank. This shoulder stands up one third of the width of
the space for the cotter to work in. The top ring fills up the remainder of the
space thus forming two large working surfaces in the recess.
These rings are cut in two halves to fit each side of the cotter and the cotter
keeping them in position when working. The reason of there being two rings is

page_text: to allow for packing or liners to be inserted between them for drawing down the
blade shanks when worn.
3rd. To obtain the sliding motion for feathering the propellor, I may either
adopt the plan set forth in my previous application or instead of having the
internal rod screwed in the coupling I screw it at the other end outside the ship.
in the boss and have the crosshead provided with a female screw, then by the
turning of the internal rod by the engine power and brake (or other means) the
crosshead is screwed to or from the propellor proper. In this case the internal
shaft will revolve not slide and will have bearings at each end. By this sliding
motion and the worm wheel (set forth in my previous application), I do away with
the large nut encircling the propellor shaft: and the thread on the shaft for the
nut now used with the Bevis boss, I also obviate the necessity and the use of
the cotter hole through the shaft, and by this means effect a great economy in
first cost.
The holes or sockets in the boss for the blade shanks are bored out in the usual
way, only being taper instead of parallel. The recess for the cotter to work in is
turned out at the same time that the hole is bored; thus making a very accurate
job and also giving two large surfaces for the packing rings or adjustable brasses
to work in.
Among the advantages I claim for this mode of manufacture are that the
V grooves on the boss and shanks of the blades, the slotting hitherto requisite in
cutting away the quarters to admit the blades and the doors on the side of the
boss for the cotters to be put through are all done away with.
The recess need not be slotted as the cotters come out through orifices in the
bonnet. The absence of doors leaves the. boss stronger and less liable to leakage
besides saving expense.
My fourth improvement relates to the brake apparatus for actuating the sliding
or rotating rod inside the main shaft. In place of the brake wheel being keyed to
the shaft it is fixed round the coupling, and in place of the worm wheel actuating
a screw on the inner shaft it can be keyed solidly to said shaft and actuate the
screwed crosshead, or a screw attached to or carried by the crosshead at the
other end.
Two other detailed improvements which I have in this invention are as follows:
The cotter is formed with projecting pieces at one end and a cap attached by &
screw at the other end both holding dovetail fashion into indents in the packing
rings, thus the cotter and packing rings mutually lock each other into place:
second in the top and bottom of the cotter bole I insert in dovetail beds a lining
or bearing for the cotter which can be removed from time to time as it wears.
I also may put screws through the packing rings, or one of them into the shank.
DaddyOLL
1
זג A
100

page_text: Improvements in or relating to Feathering Apparatus for Screw
Propellers.
I, ROBERT THOMAS BELLS, of 42 Windsor Street, Birkenhead, in the County
of Chester, 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 following statement :-
The invention is best described by aid of the accompanying drawings which are
numbered and figured in such manner as not to be confused with the numbers and
figures of some slightly revised plans of No 5208 of 1886-with which invention
in the patents for other countries this invention is incorporated.
Figures 1 to 4 are marked for convenience of reference, and show the invention
set forth in N° 5208 of 1886, Figures 1 and 2 of that application being herein
altered to conform with the drawings now filed for this application.
Figure 5 is a general elevation of the apparatus described in N° 5208 of 1886
and the present application.
Figure 6 longitudinal section of feathering propeller.
Figure 7 sections through X X Figure 6.
Figure 8 transverse section through the sockets of the blades.
Figure 9 end view with bonnet removed.
Figures 10 and 11 details of cotter and packing rings.
Figure 12 plan of a shank, showing liners in cotter holes.
In these A is the main shaft, B enlarged coupling, C central feathering shaft.
K, L, etcetera, the brake apparatus for working the same as already explained in
aforesaid Specification N° 5208 of 1886 the variation of feathering shaft shown in
the original Figure 5 of aforesaid specification being however used throughout this
Specification, rather than that shown in original Figure 4 of said Specification, that
is, having to show one plan or the other, I have shown that in which the worm
wheel traverses a screw thread on the feathering shaft, and the feathering spider,
or cross head fixed on that shaft, instead of the worm wheel fixed, and the spider
screwed up and down on the shaft, continuing therefore a description of the
drawings, U is the boss firmly fixed to the propeller shaft A in the usual
manner. U bonnet covering end of same, and attached thereto by screws,
V propeller shanks carrying blades V1; these shanks are formed extra thick and
taper to fit the tapering holes in the boss, and allow for wear and readjustment,
and both boss and shank have a recess turned out of them to admit the clutch or.
packing rings W, W¹ set forth in detail in Figures 10 and 11. These rings have a
bearing on the sides of the recesses in both the boss and the sbank, and the two
parts of the bearing are held together by solid flanges u beyond the annular slot.
X is the ordinary cotter as used in 'Griffiths' expired patent and Bevis' renewed
patent, but is provided with projecting pieces y to form a bearing surface for the

page_text: rings. The rings are screwed to the shank by screws w, and are screwed to each
other by screws w. In order to insert these, the blade being placed in position,
one half ring is shoved in and screwed up, the blade is then turned round and the
other half ring inserted. The blade is again turned round, and the cotter inserted,
then its cap, nut and check nut are added and screwed up. In this way all doors
in the boss are avoided, everything except the shanks being inserted through the
back of the boss. The ring W₁ has a recess w³ to fit the collar of the shank,
and is the one that is screwed to the shank; the ring W is separate but screwed
to it by screws w¹; the rings are recessed for the cap and cotter at yl and y". The
cotter being formed with projecting pieces y at one end, and provided with a
cap y¹¹ attached by screwed end of cotter ys and nut and lock nut y' as shown
holds the rings in place independently of the screws w. It will be thus seen that
not merely does the cotter hold the blade shank in place, but if by chance anything
happened to the cotter the packing rings bearing on both the shank and the boss
would still hold the blade, the packing rings also form a substantial stay for the
cotter. In the top and bottom of the cotter-hole I insert in dovetail beds a lining
or hearing X¹ for the cotter which can be renewed from time to time as it wears.
The hold on the shank is tightened up as it becomes slack by filing or turning off a
little from the lower ring W, and putting in a lining between the two rings, thus
again forming a firm bearing on the blade shank, and on both sides of the slot in
the bearing (above and below).
The bottom ring W' bears on the shoulder of the blade shank. This shoulder
stands up one third of the width of the space for the cotter to work in. The top
ring fills up the remainder of the space left by ring W¹ thus forming two large
working surfaces in the recess.
To obtain the sliding motion for feathering the propeller. Either the plan set
forth in the drawings can be adopted, or instead of having the internal rod screwed
in the coupling, it can be screwed at the other end outside the ship, beyond the
boss, and have the crosshead Z bereafter described, provided with a female screw,
while worm wheel D is keyed to shaft C. Then by the turning of the internal
rod C by the engine power and brake (or other means) the crosshead Z is screwed
to or from the propeller proper. In this case the internal shaft will revolve, not
slide, and will have bearings at each end. Either of these arrangements do away
with the large nut encircling the propeller shaft, and the thread on the shaft for
the nut and large cotter hole though both shafts now used with the Bevis boas.are
obviated and a great economy ip-first cost is thus effected.
The holes or sockets in the boss for the blade shanks are bored out in the usual
way, only being taper instead of parallel. The recess for the cotter to work in is
turned out at the same time that the hole is bored thus making a very accurate
job, and also giving two large surfaces for the packing rings or adjustable brasses
to work in.
Among the advantages claimed for this mode of manufacture are that the
V grooves on the boss and shanks of the blades, the slotting hitherto requisite in
cutting away the quarters to admit the blades, and the doors on the side of the
boss for the cotters to be put through are all done away with. The absence of
door leaves the boss stronger and less liable to leakage besides saving expense.
Z is the crosshead keyed to or screwed tight in shaft C in the drawings, but it
can as described be made to travel on rod C both being screwed to suit. It is
connected to the pins X' (formed in one with the heads of the cotters) by connecting
rods X³.
The mode of action is as follows:-The screw being in working position while
the engines are going ahead, the brake is applied, the rod C is slid out carrying
the cross head Z with it. This by means of the connecting rods, cotter pins, and
cotters X', X, draws the blades round to feathering position. To set the screw in
working position again the engines are momentarily reversed, the brake applied,
and the reverse action takes place.

page_text: Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1st. The manufacture of feathering propeller blades formed with conical shanks
fitting into couical bearings in the boss whereby as wear occurs they can be
readjusted.
2nd. The combination of the feathering propeller bla le sbanks, and boss sockets,
both recessed out, with the packing ring or rings (W W¹) having a bearing both
on the recess in the shank, and that in the socket, substantially as and for the
purposes described.
3rd. The clutch or packing rings formed in two parts both longitudinally and
transversely, and having a bearing on the cotter, substantially as and for the
purposes described.
4th. The several improvements in or connected with the cotter for more securely
holding it in place in the packing rings, and also for taking up the slack,
substantially as and for the purposes described.
5th. The improvment in the boss of a feathering, propeller which consists in
turning or cutting away a sufficient amount of the metal near the shank socket,
and where the cotter or lever works (replacing it with outer web) to enable one to
take the cotter out and in through the back of the boss, instead of through the side
whereby the use of doors is obviated, and a stronger boss obtained.
Dated this 11th day of August 1886