IMPROVEMENTS IN THE MANUFACTURE OF FRICTION COUPLINGS AND APPLIANCES COMBINED THEREWITH
Year: 1884

page_text: I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the County
of Middlesex, Civil Engineer and Patent Agent, do hereby declare the naturo of
said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF FRICTION COUPLINGS
AND APPLIANCES COMBINED THEREWITH," to be as follows:-
This invention relates to friction couplings of the type in which levers project
from one part and are actuated by a cone or other device moving on the other
part to engage and disengage the clutch.
Imperfections in the workmanship or wear of the parts frequently causes the
action of the levers to be unequal; so that the ordinary friction clutches, which
depend upon absolute mathematical exactness of the position of the parts relatively
to each other, are often defective in their action. According to the present
improved construction, the levers may be acted on with any required amount of
inequality, even to the extent of one remaining idle and another or others doing
all the work, without involving any mischief. The strain on all the levers will be
equal and the friction on all the friction-surfaces will be equal, whether the levers
are actunted evenly or unevenly.
Efficient means are provided for fixing the hub of the wheel, or a corres- portion
of a coupling, centrally on the shaft, and also for liberating the hub or coupling
from rigid engagement with the shaft. The oxterior or effective pulley is formed
in two parts very firmly joined together; and special means are employed for
mounting a pulley on a hub detachably and exactly centrally; so that a great
number of sizes of pulleys can be worked successively on the same hub to give
different speeds to the machinery, and different hubs may be used with the same
pulley to adapt it for different sized shafts.
Supposing the invention to be applied to two lengths of shafting of equal size,
mounted axially in line with one another and intended to be connected and
disconnected at will; tho changes being made with the gentleness peculiar to
friction clutches, while allowing the workmanship to be imperfect and the action
of the levers unequal:-A hub is firmly and concentrically set on one of the shafts
by means to be hereafter described. A cylindrical box is formed on one end of
the hub, open on the face presented towards the other shaft, with the inner

page_text: surface finished smoothly. A stout collar, concentrically set on the other shaft,
carries a stout projection or dog which engages in a rocess in a series of segments
arranged to revolve within the cylinder. The engagement of the dog with these
shoes is looso, so that there is liberty for some movement. The segments may be
expanded outward to tightly fill the cylinder, and induce a strong friction against
the interior thereof, by any sufficient means applied in the joints where the
segments abut against each other. Such frictional engagement of the segments
with the cylinder causes the revolution of one shaft to compel the revolution of
the other. The result will equally follow whether the separation of the segments
at these joints be equal or unequal. If it be all at one joint, it will crowd the
segments together at the other joints, but with no mischievous effect; the bearing
of the exteriors of the segments against the interior of the cylinder being equally
effective. On again contracting the segments, the frictional connection will bo
broken, and one shaft will revolve again independently of the other.
The distension of the segments is effected by helical wedges, one at each joint,
ench equipped with a lever extending in the direction of the shaft and adapted
to be actuated by a moveable hollow cone or wedge-sleeve, which may be traversed
on the shaft by a suitable shipper. Instead of traversing the wedge-sleeve
directly on the shaft, it may be mounted and traversed on an extension of the
same collar which carries the dog actuating the segments. The helical wedges
may be made with only one such wedge-face and the other face plane; but this
design may be varied. The segments are preferably not of uniform thickness, but
with a wide outer bearing surface to make the friction, a thinner web extending
inward therefrom, and again a wide bearing surface at the inner edge to bear on the
.collar. The web may with advantage be provided with an enlargement or
thickening at each end. Such enlargements accommodate the centre-pins of the
helical wedges; and also, at one end of each segment, receive an adjustable picce,
which may be termed a cam having a helical wedge-surface presented towards the
helical wedge. The cams may be partially turned in one direction or the other
and held by pinching screws. Turning each one way tightens the grip of the
segments in the cylinder with a given movement of the levers. Turning them
the other way relaxes the grip. By this means, the action can be modified with a
given movement of the levers. This is useful in adjusting the parts at first and
also in compensating for wear.
Whenever the proper movement of the levers does not induco sufficient friction
within the cylinder, the friction should be relaxed and the cams re-set, after being
turned a little in the direction to tighten the grip. The adjustment may be
effected by turning all the cams slightly, or by turning one alone.
A long spiral spring extends around in the segments, lying in a proper channel
formed to receive it. The effect of this spring is to draw the segments inward
and relieve the parts from friction, so soon as the levers are allowed to come
inward..
Instead of a continuous spiral spring extending quite around, I can emply a
separate spring for each joint. Such a modification may be preferable with large
'clutches.
L
On the hub or on the cylinder carried therewith, a stout nicely finished lip is
formed; the same performing an important function by engaging in a corresponding
groove in an exterior removable pulley. Several different sizes of these exterior
pulleys may be provided, each equipped with a similar groove, and each provided
with a suitable inner rim to be securely attached by bolts or other fastenings to
the cylinder which contains the friction work or to the hub which carries the said
cylinder.
These interchangeable parts may be used to give different sizes of effective pulloys
with the same friction mechanism in the centre; or a single exterior pulley may
have different hubs and friction mechanism adapted for use on different sizes of
shafts. The lip and groove insure an exactly concentric position of the exterior
pulley on the friction mechanism.

page_text: The hub is secured on the shaft by means of wedges engaging in wedge-shaped
recesses formed on the hub. The inner face of each wedge is hollowed to a radius
a little less than that of the shaft. There are three or more of these wedges
arranged equi-distant around the shaft. The inner face of one of the wedges is
splined longitudinally and receives a loosely fitting key or feather, which, by also
engaging in corresponding splines in the shaft, provides against a possible turning
of the parts on the shaft.
The wedges, if driven equaliy, ensure a perfectly concentric position of the
cylinder on the shaft. To drive them equally, a ring is applied which is screw-
threaded on its exterior and set in a corresponding screw-threaded annular recess
in the hub-end. An adjustable projection is formed on the inner face of the
screw-ring by tapping a round-ended screw through the ring. When the wedges
are in place and the screw-ring applied and screwed home, its ndjustable projecting
screw-end may be let back to pass each wedge successively, thus forcing each to a
less and less extent until all are equally home. It is practicable to drive the
wedges by a hammer. In either case, the screw-ring may hold them firmly and
uniformly in position.
:
In the process of manufacturing the apparatus described, the wedges are first
produced, the thickness of these being greater than ultimately intended for the
same. They are then mounted in the core in a position farther inward than they
are to subsequently occupy. The core with its wedges are then placed in a
suitable mould; and the melted metal for the hub, being poured in, fits around the
core and around the wedges. When the casting thus produced is cold, it holds the
wedges with sufficient firmness to allow the inner face of each of the several
wedges to be finished with the proper hollow by boring in a lathe or boring
machine. The boring is produced to a smaller radius than the shaft; whereupon
the wedges, having their inner faces thus finished, are detached from the hub;
and after the latter has been mounted on the shaft, the points of the wedges are
re-inserted in their wedge'cavities and the wedges driven equally home, as above,
described.
The interchangeable pulleys are made in two parts peculiarly clamped together.
The clamps are made first and set in the mould, so that the melted metal of tho
pulley may be shaped by flowing in contact therewith. Each clamp has a hook-lip
at each side, which engages with a corresponding hook portion of the pulley. The
middle of each clamp is also formed with a ridge of V-section. The clamps aro
wedge-formed transversely, and are applied and removed by forcing them laterally.
They may be driven by hammers or by a screw-press or by a hydraulic press.
Each may be held by any approved means.
In making the pulley, the two parts aro cast in one with the clamps in position;
and then, after finishing the exterior of the pulley and also the central hole and
removing the clamps, the halves are cut or broken apart. A locking key, a
pinching screw or the like, may be used to secure the clamps in position.
This invention is applicable to other situations than where two shafts, axially
in line with one another, are required to be coupled. It may be applied for
engaging a shaft with a pulley so that the pulley shall be fast or loose with the
shaft, according as the friction segments are forced outward or drawn inward.
The use of three segments is preferred, but a greater number may be employed; or
even two may serve.
By finishing the exteriors of the helical wedges and mounting them in close-
fitting recesses in the segments, dust may be excluded from the principal working
surfaces.
G. G. M. HARDINGHAM.

page_text: COMPLETE SPECIFICATION.
"
I, GEORGE GATTON MELHUISH HARDINGHAM of 191, Fleet Street, in the County
of Middlesex, Civil Engineer and Patent Agent, do hereby declare the nature of
said invention for "IMPROVEMENTS IN THE MANUFACTURE OF FRICTION COUPLINGS
AND APPLIANCES COMBINED THEREWITП (communicated from abroad by John
Charles Blevney, of Newark, in the County of Essex and State of New Jersey, one
of the United States of America, Engineer), and in what manner the same is to
be performed to be particularly described and ascertained in and by the following
statement:-
My friction coupling or clutch is of that class in which levers are actuated by a
cone or other device to engage and disengage the clutch. Imperfections in the
workmanship or wear of the parts often make the action of the levers unequal,
so that the ordinary friction-clutches which depend upon absolute mathematical
exactness of the position of the parts relatively to each other are defective in their
action.
I have devised a construction in which the lovers may be acted on with any
required amount of inequality, even to the extent of one remaining idle and
another or others doing all the work without involving any mischief. The strain
on all the levers will be equal and the friction on all the friction-surfaces will be
equal, whether the levers are actuated evenly or unevenly. I employ efficient
means for fixing the hub of the wheel or a corresponding portion of a coupling
centrally on the shaft, and also for liberating the hub or coupling from its rigid and
central engagement on the shaft. I make the exterior or effectivo pulley in two
parts, very efficiently joined together. I employ special means for mounting a
pulley on a hub detachably and exactly centrally, so that a great number of sizes
of pulleys can be worked successively on the same hub, to give different speeds to
the machinery, and different hubs may be used with the same pulley to adapt it
for different sized. shafts.
The following is a description of what I consider the best incans of carrying out
the invention. The accompanying drawings form a part of this specification.
Figure 1 is an end elevation certain portions being broken away to show the
interior.
Fig. 2 is a corresponding central longitudinal section.
Fig. 3 is an end elevation of the parts immediately adjacent to the shaft, showing
the provisions for fixing the parts rigidly and centrally together.
Figs. 4 and 5 show the provisions for driving and holding the wedges on a larger
scale. Fig. 4 is an end view, and Fig. 5 is a side view.
Figs. 6 and 7 show a modification. Fig. 6 is an end view, and Fig. 7 a central
cross-section.
Figs. 8 and 9 show the provisions for removing the wedges when such shall
become necessary. Fig. 8 is a side view, and Fig. 9 an end view.
Fig. 10 is a side elevation showing a modification of the principal parts.

page_text: Figa 11 to 14 show the means for producing the proper recesses in the hub to
receive the wedges. I will for simplicity omit the provisions for making the
cavities for operating the keys. Fig. 11 is a central longitudinal section through
the core on the line in fig. 12. Fig. 12 is a horizontal section on the line y y
in fig. 11. Fig. 13 is a longitudinal section through the completed hub after the
wedges have been displaced and one has been partly reinserted. Fig. 14 is a
corresponding section on the line as in fig. 13.
Fig. 15 is a sectional view of a modification.
Similar letters of reference indicate corresponding parts in all the figures where
they occur.
A and P are two lengths of shafting of equal size mounted in line. A is the
driving-shaft. The object of the clutch is to connect A with P at will, and to
disconnect it therefrom, and to make the changes with the gentleness peculiar
to friction-clutches while allowing the workmanship to be imperfect, and the action
of the levers unequal.
B is a sufficiently stout hub. Certain portions will be designated when necessary
by reference letters B¹ B. It is firmly and concentrically set on the shaft ▲ by
means which will be described further on.
B¹ is a cylindrical box on one end of the hub B and open on the face presented
toward the other shaft P. The inner surface of this cylinder is finished very
smoothly.
Qis a stout collar, a portion of which will be designated when necessary
by reference-letter Q. It is firmly and concentrically fixed on the shaft P. The
friction is made or relaxed at will on the interior of the cylinder B¹ by three
segments or shoes R R R, carried by the collar Q. A stout projection or dog Q₁ on
the collar Q engages in a recess in the parts R; but the engagement is so loose that
there is liberty for some movement. The segments R may be expanded outward
so as to tightly fill the cylinder B' and induce a strong friction against the interior
surface thereof, by any sufficient means applied in the joints where they abut
against each other. The result will equally follow whether the distention of these
segments by their separation at the joints is uniform or unequal. If the separation
is all at one point it will crowd the segments together at the other joints, but with
no mischievous effect. The bearing by the exteriors of the segments against the
interior of the cylinder will be equally uniformn and effective. On relaxing the
distending force the segments may be brought inward again toward the collar by
any gentle force.
TTT.are spiral wedges, partial screws, partially-revolving wedges, or spiral-
ended bosses mounted in the spaces thus provided. Each is plane on one end and
abuts against a corresponding plane face on the adjacent segment. Each is helical
or screw-formed on the opposite face, as shown at e', and abuts against a corre-
sponding surface on the opposite segment R. Each is provided with a lever T',
which extends in the direction of the shaft P, and is adapted to be actuated by a
movable wedge-sleeve W, which is arranged to traverse on the fixed collar Q, being
actuated by any suitable shipper (not represented). Each segment R is formed
with a web R, a broad unobstructed bearing-surface R on its periphery, and
approximately corresponding bearing-surface R on its inner face, and a considerablo
enlargement or thickening of the web at each end, which accommodates the centre-
pin of the corresponding levers T'. The enlargement at one end of each segment R
is sufficient to also receive an adjustable piece E, which I will term a cam,"
having a spiral wedge or helical surface e'.
"
FFF are pinching screws which hold E firmly. There is a notch or score e into
which any suitable tool may be introduced through a slot in the segment, and by
which, when the pinching-screw G is relaxed, the cam E may be turned partially
around and again secured in a new position. This adjustable cam enables me to
set the segments to work more casily or loosely in the cylinder B¹, as required from
time to time to compensate for wear, or for any other reason.

page_text: A channel is provided in the series of segments. extending quite around.
A
long spiral spring S extends around in this channel and is united at its ends so as
to form a continuous ring. It exerts a sufficient contractile force to draw the
segments R inward as soon as the distending force due to the action of the levers T¹
and their wedge-faces e' is relaxed.
Fig. 10 shows a modification of this portion of the mechanism. Instead of a
continuous spiral spring extending quite around, I employ three separate spiral
springs, one for each of the joints or spaces between the several segments R. One
of these is indicated by S*. It is attached directly to one segment and exerts a
tensile force on a rod which connects to the other segment. This construction may
be preferable under some conditions where the action of the several levers T' keeps
the distention at the several joints tolerably uniform. When, with this modification
the springs shall differ in stiffness and thus exert different forces, they can be
made approximately equal by adjusting the cam E, to work the segments nearer
together where the spring is stiffest. This construction is preferable for the largest
sizes of friction-clutches. For small and medium sizes I prefer one continuous
spiral spring as first described.
B2 is a stout finished lip of rectangular section formed on the cylinder B¹ in the.
position represented.
D is a wheel adapted to form the exterior or working portion of the pulley,
certain portions being designated, when necessary, by reference letters D' D'. The
peripheral surface or outer rim D' is adapted to receive a bolt (not represented).
D¹ are spokes or arms extending inward from the peripheral rim D³, to an inner
rim D³. The lip B engages in a correspondingly finished groove in the inner
rim D³, which by bolts C or other efficient means is firmly secured to the
cylinder B¹ and turns therewith.
When it is desired to change the size of the pulley, the exterior portion D is
removed and another substituted of larger or smaller size, and bolted in place, the
inner part or hub B B' B' not being changed or disturbed. The finished lip B²
engaging in the correspondingly finished groove in D³ holds the parts concentric
with but little labor in finishing, and without depending for the concentricity on
the holding-bolts. I have shown the wheel D as mado in two parts and secured
together by the means to be set forth below.
K is a ring, screw-threaded on its exterior and engaged with corresponding
screw-threads b, in an annular cavity formed in the end of the hub B.
I II are three equally spaced wedges, each hollowed on its inner face to a radius
a little less than that of the shaft A. Each is fitted in a corresponding wedge-
shaped space provided in the hub B. Each has a notch on its outer face. There
is a recess b' in the hub corresponding to each wedge I, which allows the insertion
of a hook L, to be properly operated by a screw-device working in the scrow- 4
threads b, by which I effect the removal of the wedges I when necessary. The
removal is effected by placing the bar O across the recess b₁, engaging the hook L
in the notch i¹, and turning the nut to draw forcibly on L. The hub B is held
by the wedges I absolutely concentric to the shaft A, provided the wedges aro
driven to a uniform extent. The screw-ring K. insures that the wedges shall be
uniformly held.
Figs. 6 and 7 show a temporary screw-ring K with a wedge-shaped projection K'
on the side.
This screw-ring is applied with the projection K' towards the heads
of the wedges, and as it is strongly turned by a suitable wrench the projection K¹
acts on the several wedges in succession concentrating all the force at any given
period on one wedge. After the wedges I are thus forced to a firm bearing this
temporary screw-ring K K¹ is withdrawn, and a permauent ring having no such
projection K', is applied. This on being forced down into contact presses in ward
only the one or two which are first touched, and finally remains fairly against the
whole and keeping them firmly in place.
Figs. 4 and 5 show a corresponding construction, but with the projection K" in
the form of a rounded end on a sinall screw, which is tapped through the substance

page_text: of the ring K, as shown. This affords the advantage that when the wedges are
nearly home they resist motion to such an extent that the projections K' K"
cannot be forced past a certain wedge, the secondary screw K." may be turned
backward a little, and then the main screw-ring K turned again until it is caused
to pass. The effect is to force the wedge in to a less extent. Thus by acting on
each successively the last slight motion may be imparted to all the wedges.
One advantage due to the fact that my screw-threaded ring K. has its screw-
threads on the exterior and engages in a correspondingly threaded recess b in the
bub, is that the hub may be threaded by a tap. The ring K is easily threaded on
its exterior in any common lathe. These wedges may also be driven either by the
direct pressure of the screw-ring K, or by blows with a sufficiently heavy hammer,
which may be impressed on the several wedges I, through the medium of a set or
short bar of iron applied successively on the ends of the several wedges. Those
blows may be mainly given before the ring K is applied. After K is introduced
and screwed home, further blows may be given with some effect and the ring
farther driven to follow up until all the wedges are evenly and very tightly set.
The applying and removing of the wheel or pulley D is facilitated by making it
in halves. It is cast in one piece and cut or broken apart after the finished
exterior is turned, or otherwise properly smoothed and trued, and the groove is
finished in which to receive the lip B². The halves are subsequently secured
together with unusual strength and rigidity by clamps F*, certain portions
being designated when necessary, by reference letters as F1 F2. These clamps are
first produced by casting or otherwise, in the form required with engaging
flanges F, F, along the edges, and the V-sectioned ridges F³ along the centre.
The flanges are a little nearer together at one edge than at the other. When the
pulley is cast, these clamps are placed in position in the mould, or in suitable cores
inserted in the mould, so as to properly hold the clamps. Then the melted motal
of the pulley or wheel D, flowing against or around the clamps makes a perfect
fit. After the pulley is removed from the sand aud is cold, the clamps F* are
detached by driving them laterally, the pulley is finished and cut or broken apart
and the clamps F* replaced. A locking key or other means may be provided for
insuring the retention of each clamp F; but my experiments indicate that such
will not be necessary. I have shown but one clamp F*. It will be understood
that there is another on the inner face of the rim at the opposite side. There will
also in large pulleys be one such clamp similarly locking with the metal of the
wheel on the outer face of the inner rim D³, at the points where such rim is
broken or cut. My clamps not only hold the wheel firmly together by their
flanges FF, but also by their V-shaped central ridges F3 hold the joint very
stiffly against any working of the parts under any strain. In the wheel D I have
marked the beveled recesses d, and the clamping projections D'.
It will be observed that the ridge F³ of the clamp F* not only serves to
strengthen the clamp, but also to render the finished pulley easily broken at that
point. I have shown this ridge of V-shaped form; but this form may be modified,
as any plato with tapering projections which will allow metal to be cast around it
as described, will meet the requirements of the invention.
It will be observed by the construction illustrated that I use the screws C C to
fasten the pulley D to the cylinder B' or the hub B; but it is obvious that I may
finish the rib B³ with inclined sides, the diameter diminishing toward the base, and
form the hub D³ of the pulley to match, with the bore slightly smaller than the
rib, all as seen in fig. 15. In such case the clamps as F, will hold the pulley
centrally and firmly without said screws C. In large pulleys I would insert
a feather or pin between the adjoining surfaces of B and D³. It is understood
that in such case there is no necessity of the hub D³ overlapping the rib.
In the manufacture I first produce the wedges I and then fit them deeply sunk
in the core H, which is to shape the interior of the hub B. Thus the hub is cast
with these. wedges in their correct position circumferentially, but projecting too

page_text: far inward. When the metal is cold the wedges will be held in their positions
in the hub with sufficient firmness to allow the hub to be strongly held, and
a boring-tool applied to finish the entire inner surface of each wedge, reducing
it exactly to the form required, with a slightly greater curvature than matches
the shaft. After this is done the wedges, after being properly marked, may
be detached froin their seats by sufficient force, and either with or without
slightly filing or otherwise reducing the surfaces they may be returned to their
places ready to be tightly driven home. For increased security I mill or otherwise
produce a recess α, in the shaft A, and a corresponding recess i in one of the
wedges I, and apply a feather J loosely therein having a head J, which prevents
its escapo end wise. This insures against any considerable displacement of the
hub B; but I believe the feather will only rarely be of service. My experiments
show no slipping of the wedges around on the shaft. I have shown the collar Qas
similarly held on the shaft P, but this is not material. The collar Q may be held
by any efficient means. It is mainly important that the cylinder B' and the pulley
surface D' be concentric to each other and to the shaft A. Whenever the wear of
the rubbing surfaces shall make it possible to throw the levers T out to their full
proper extent without inducing sufficient pressure in the cylinder B₁, one of the
pinching-screws F must be slackened, and the cam E turned in the direction to
contract the space for the boss T. Then the screw G must be tightened again.
The ends of the segments may be tongued and grooved, so that they can be drawn
together or spread apart within certain limits without opening a joint through
which dust may pass.
Modifications may be made in the forms and proportions within wide limits
without departing from the principle or sacrificing the advantages of the invention.
Instead of three segments or shoes R, and a corresponding number of lovers T",
I can use two with success, or four, or even a greater number. I can use parts of
the invention without the whole. I can dispense with the adjustable cams E and
form the helical or spiral wedge-surfaces e¹ in the required positions directly on
the proper segments R. Each side instead of one side of each boss T, may be
formed with a helical surface and made to work against a corresponding helical
surface on the adjacent segment R. Each lever T₁ may have a roller to diminish
the friction on the wedge-sleeve W. Instead of making the web R¹ of cach
segment R in the plane of the centres of the bosses T, it may be in front or nearer
the shaft P. It is important to make as close a fit as is practicable of each
segment to the boss T, in order to exclude dust. The web of the segment (by
which I mean the metal R¹ which connects the outer rim K with the inner rim R³,
as shown,) is made to fit closely but easily to the surface of the boss T. It may bo
continuous, with the exception of a sufficient space to allow the levers T¹ their
greatest vibration. I have shown the invention applied to coupling two shafts, A
and P. The invention may be equally well used to connect and disconnect a pulley
and shaft. In such case what I have shown as the two shafts A and P, will be one
continuous shaft. The only alteration necessary is that the hub B must he loose
on the shaft, and some provision, as a collar (not represented) fixed on the shaft
opposite the collar Q, to hold the hub B in its proper position end-wise. Then
when the wedge-sleeve W is moved away and the lever T¹ and segments R move
inward, the pulley turns on the shaft without communicating motion thereto, or
receiving motion therefrom, as the case may be. When, on the contrary, the
wedge-sleeve W is shifted to throw out the levers T and the segments R, the
friction takes hold on the interior of the cylinder B' and communicates the motion
strongly.
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
1. A split-pulley having clamping-surfaces D' and beveled recesses d, in com-
bination with clamps having flanges FF, and engaging ridges F³, arranged to

page_text: 2. The headed feather J J', wedges I, having recesses i and screw-ring K, in
combination with each other and with the hub B and shaft A, as herein specified.
3. The shaft A, hub B and wedges I, in combination with each other and with
the screw-ring K, having a projection K¹, arranged to serve as herein specified.
4. The wedges I, having each a recess i on its exterior face, in combination with
the hub B having recesses to receive the wedges, and also longitudinal recesses b,
as shown, and with the shaft A, bar O, hook-bolts L, and nut l, adapted to serve
in withdrawing the wedges, as herein specified.
5. The hub B, cylinder B' fixed thereon, and expansible segments R, in com-
bination with each other and with the wedges I, all operated as described, and
arranged to serve as herein specified.
6. The hub B secured to shaft A, and finished lip B³, in combination with the
shaft A, exchangeable pulley D, matching said lip B³, and with suitable fastenings C,
arranged for joint operation; as herein specified.
7. The hub B and cylinder B¹, having a finishod lip B³, in combination with the
friction-segments R, operated as described, and with the exchangeable wheel or
pulley D, having a corresponding finished groove to receive said lip, and with
fastenings C, all arranged for joint operation, substantially as herein specified.
8. The sbaft A, wedges I, feather J J', hub B, having cylinder B¹ and lip B³,
friction segments R, and operating means T T W, exchangeable pulley D, and
fastening means C, combined and arranged to serve as and for the purposes herein
specified.
Dated this twelfth day of March 1885