Year: 1888

page_text: Date of Application, 4th Jan., 1888
Specification Accepted, 23rd Mar., 1888
1, OTTO FLOHR, of No. 1528 Main Street, in the City of Buffalo, in the State of
New York, United States of America, Machinist, 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:-
This invention relates generally to that class of clutches by which one rotary part is
coupled to, or uncoupled from, another at will and without regard to the direction of
rotation.
More specifically, it relates to clutches wherein the one moving part is constructed
with an overhanging flange, and the other moving part carries a divided friction ring,
which may be expanded within said flange in order to bind the two parts together, or
slackened in order to disconnect them. Such clutches have heretofore been made in
which the divided ring expanded within the flange by means of wedges forced in
between the sections of the ring.
Similar clutches have also been made wherein the sections of the expanding ring
have been forced apart by levers pivoted to the sections, or pivoted to, or borne by,
their carrier.
Clutches of this character have also been constructed wherein the sections of the
ring are spread apart by means of toggles. In this way a clutch of great power can
be made with but few parts, and those of simple and cheap construction. It is to
clutches of this kind that my invention pertains.
I provide two or more toggle-arms with their outer ends braced or seated against
the sections of the ring, and their inner ends against a knee-piece, which is movable
in longitudinal direction, being moved to apply or release the clutch through the
medium of rods and levers, or other usual or suitable mechanism for the purpose.
The sections of the ring, preferably two in number, are drawn together by springs
and are forced apart by the straightening of the toggles.
In order to provide a ready and powerful means of applying my improved clutch,
I arrange a screw in connection with the usual grooved sleeve to which the rods are
fixed through the medium of which screw the sliding knee-piece is moved, so that
by turning this screw in one direction or the other, the knee-piece is either advanced
or retracted and the clutch, consequently, either applied or released,

page_text: Figures 1 to 12 inclusive, of the accompanying drawings illustrate my invention in
its preferred construction.
Fig. 1 is a longitudinal mid-section of a hoisting drum and clutch cut in the plane
of the line 1-1 in Fig. 2.
Fig. 2 is an elevation looking in direction parallel with the axis of rotation and
partly in transverse section, as indicated by the dotted line 2-2 in Figs. 1 and 3.
Fig. 3 is a fragmentary longitudinal mid-section cut in the plane of the line 3-3
in Fig. 2.
Figs. 4 and 5 are respectively front and rear elevations of the knee-piece.
Fig. 6 is a front elevation of the divided friction ring.
Fig. 7 is a plan of the mechanism for applying or operating the clutch.
Fig. S is a side elevation thereof, the frame of the machine being shown in
transverse section.
Fig. 9 is a front elevation of a portion of a hoisting engine embodying my improved
construction of clutch.
Fig. 10 is a fragmentary front elevation partly in vertical section cut in the plane
of the lines 10-10 in Figs. 7 and 8; and
Fig. 11 is a plan of the same parts partly in horizontal section, as denoted by the
line 11-11 in Fig. 10.
Fig. 12 is a perspective view of one of the socket blocks.
Referring to Figs. 1 to 11, let A denote (for instance) the drum-shaft of a hoisting
engine, B the driving gear fixed thereto, C the winding drum mounted loosely thereon,
and D the fixed frame work of the engine. In hoisting, the gear Bis rotated by the
engine, the drum C is coupled to the gear through the medium of the friction clutch,
and is revolved thereby until the load is raised to the desired height. Then, when it
is desired to lower the load, the clutch is partially released, and the drum is thereby
permitted to be revolved backward by the descent of the load, the rapidity of its
backward revolution being governed by the clutch, which then acts as a friction brake.
The gear wheel B is formed with an annular overhanging flange a, and within this
flange is placed the divided friction ring E. This ring is divided at diametrically
opposite points into half-sections, as shown in Figs. 2 and 6.
The friction ring is carried by the drum, the latter being formed with an expanded
flange b, to which the ring is connected through the medium of carrying-pins F F,
shown in elevation in Fig. 1, and in transverse section in Fig. 2. These pins are
screwed securely into the flange and their heads enter recesses or sockets, c c in the
opposite sections of the divided ring (see Fig. 6), so that the ring is forced to turn
with the drum, but the sections are free to be moved slightly from or toward each
other.
The two sections of the ring are formed with flanges d d at their division, and a
pin or stud e is screwed firmly into one of these flanges and passes freely through a
close-fitting hole in the other Hange. There are two studs e on opposite sides, arranged
parallel to each other, so that they serve to guide the sections in their expanding and
collapsing movement, and keep them in proper alignment. On each stul e is placed
a stiff spring G, which is confined by nuts screwed upon the end of the stud. The
two springs G G serve to draw together, or collapse, the sections of the ring.
The gear B is formed with a prolonged hub fitting the shaft A, and on the exterior
of this hub, which is turned to a true cylinder, is fitted the "knee-piece" H, which is
shown detached in Figs. 4 and 5. This knee-piece is free to slide on the hub ƒ in a
direction parallel to the axis of rotation. Four toggle-arms I are arranged in radial
manner, as shown in Fig. 2, between the knee-piece H and the ring E. Both the
knee-piece and the ring have recesses or sockets which receive the respective ends of
the toggle-arms. The sockets in the ring are lettered g g (Fig. 6), and those in the
knee-piece are lettered h (Fig. 5). The sockets in the knee-piece are by
preference, formed in separate detachable blocks JJ, as shown in Figs. 2, 3 and 5.
Fig. 12 is a perspective view of one of these blocks. These blocks should be made of
hard steel, in order to reduce the wear. They are fitted into angular sockets in the
knee-piece, as shown in Fig. 3, in such manner that they cannot become displaced.

page_text: The ends of the arms II and their respective sockets 7 h, are rounded to fit each
other.
Thus the
The proportions of the parts should be such that the toggle-arms will stand at about
the angle shown in Fig. 3. It is obvious, referring to that figure, that on forcing the
knee-piece H to the right, the toggle-arms will be pressed outwardly against the
sections of the ring, and somewhat straightened, and that thereby the sections of
the ring will be forced outwardly against the inner surface of the flange a.
clutch is applied, and the two moving parts, B and C, are coupled together. On
moving the knee-piece H to the left, the pressure against the toggle-arms is relieved,
and the sections of the ring are released, whereupon their springs G G draw them
together, so that the ring no longer presses against the flange a, and the two moving
parts B and C are uncoupled or disconnected.
It is desirable to provide some stop for limiting the retractile movement of the
knee-piece, as otherwise the springs GG, acting upon it through the medium of the
ring sections and toggle-arms, would force it too far to the left (in Figs. 1 and 3) I
therefore provide a flange or collar i, which is placed against the left hand or front
end of the hub and screwed thereto, as shown in Fig. 1.
When the retractile
movement of the knee-piece brings it against this flange i, it is stopped.
The advancing and retractile movements of the knee-piece H are imparted to it
through the medium of rods K K, which are carried by the drum and slide longitu-
dinally through holes therein, and are fixed at their front ends to a sliding sleeve L,
which is mounted to slide freely on the shaft A, and has an annular groove 1, into
which projects any suitable moving part by means of which the requisite longitudinal
movement may be imparted to the sleeve. This is the usual construction heretofore.
adopted in clutches of this character.
My improved construction of friction clutch has the advantages of enabling the
respective moving parts to be coupled together very powerfully with but slight
exertion on the part of the person operating it, of effecting a free and quick release:
and of uniformly distributing and equalizing the strains incident to the forcing of the
frictional surfaces together. There is but little wear, and such as there is will be
compensated automatically by the moving parts for a considerable time.
In constructing the clutch the toggle-arms and their connections should be
accurately proportioned and fitted, although slight inequalities will be compensated
for by the self-adjustment of the parts. If my preferred construction be adopted,
wherein the sockets h h are formed in separate blocks JJ instead of in the knee-piece H
itself, the proper adjustment of the machine will be greatly facilitated. For example,
if, after putting the parts together, any one or two of the toggle-arms are found to
sustain less strain than the others, the blocks J J against which those arms are
seated, are taken out of their sockets and a piece of paper, cardboard, or sheet metal
of the proper thickness is inserted under each block, thereby lifting it away from the
center of the knee-piece, which has the same effect that the insertion of a longer
toggle-arm would have. The same construction enables the wear of the machine to be
taken up, whenever necessary, which would only occur at long intervals, whenever
the parts have worn to such extent that the toggle-arms are straightened out
to too obtuse an angle. This is done by underlaying the blocks J J of all four
toggle-arms.
Instead of providing the knee-piece with removable blocks JJ, the sections of the
ring may be thus provided as shown in Fig. 15, which is a fragmentary section of the
ring, knee-piece and toggles, answering to Fig. 3. Or, blocks may be provided in
both the knee-piece and the ring.
My invention is susceptible of various structural modifications without departing
from its essential features. There may be more or fewer of the toggle-arms I I, two
being the smallest number that can be made operative; the friction ring may be
livided into more or fewer sections with one, two, or more toggle-arms to each
section; different means may be provided for collapsing the sections of the ring; and
other devices may be employed for imparting motion to the knee-piece. will
resently describe a construction embodying these modifications.

page_text: .
I will now describe the mechanism which I have devised for imparting the clutching
and releasing movements to the sleeve L.
The shaft A has its bearings in the side frame 1), as usual, a bearing cap M being
fixed over the journal. This bearing cap 1 extend upwardly, as best shown in Fig. 10,
it being formed with side ledges kk, and with upwardly projecting walls or
flanges m m. On top of these walls is fastened a top-plate N, which has wings or
flanges nn, which project beyond the walls mm, and correspond to the ledges k k
beneath them. In the space between the walls mm, beneath the top-plate N, is con-
fined a slide P, which is so guided in this space as to be capable of free longitudinal
movement. The rear end of this slide is turned downardly and enters the groove in
the sleeve L, (Figs. 1 and 8). Thus the sleeve is free to rotate, while being held
stationary in longitudinal direction by the slide P, and the longitudinal movement of
the latter effects a like forward or backward movement of the revolving sleeve.
A yoke has its arms bolted to the walls m m, being confined in place vertically
by the flanges n and between which they are closely confined. In the front portion
of this yoke, which extends across in front of the end of the slide P, is formed a
threaded hole, or socket, in which turns a screw R, on the front end of which is fixed
a hand wheel S, as shown in Fig. 1, or a crank lever, as shown in Figs. 7 and 8.
The rear end of the screw R enters a socket in the slide 'P, and is swiveled therein, by
means of one or more pins p p in the slide entering a groove in the screw, so that as
the screw is turned, and this moves forward or backward the slide is caused to move
forward or backward with it.
By turning the hand wheel or crank S in one direction or the other, the
parts P, L, K and H are advanced or retracted, and the clutch is either applied. or.
released. But a very slight motion is required to either apply or release the clutch;
and by imparting this motion through the medium of a screw and lever (namely, the hand
wheel or crank S) a considerable mechanical advantage is gained, and the operator is
enabled to regulate to a nicety the pressure applied to the frictional surfaces. This
construction renders it practicable to use my friction clutch as a brake to regulate.the.
speed of descent of the load which has been hoisted. A very slight turn of the wheel
or crank S, will cause the load to descend faster or slower, the control being as perfect
in this respect as with any brake now in use.
Fig. 9 shows a portion of a hoisting engine to which my invention is applied.
Only that end of the machine which carries the hoisting gear is shown. The steam.
engine may be constructed in any way desired; as, for instance, like any usual
hoisting engine. D is the side frame, O is the pitman, U is the crank wheel, which
is fixed on the crank shaft V, 7 is the driving pinion, (the pitch line of which is
shown by a dotted line,) which is fixed on the shaft V, and which gears either directly
with the gear wheel B, (shown by a dotted pitch line), or with a slow-motion gear.
wheel W (also shown by a dotted pitch line), and which in turn drives the
gear B through the medium of a pinion w, (indicated in like manner by a dotted
line). This is the usual construction of hoisting engines whenever either a slow or
quick motion is desired. C is the winding drum, A the drum shaft; S the crank wheel
for applying the clutch, and R its screw. Y is a ratchet wheel, or notched wheel, which
is carried by the drum, being constructed in the form of a ring and bolted to the end
of the drum, as shown in Figs. 1 and 7..
It is frequently desirable or necessary to have some means for locking the drum
fast in position, in order to hold the load suspended at any desired point,
independently of the action of the clutch and engine. For this purpose I provide a
locking pawl, or. hook X, which pivoted to the fixed frame D, and the hooked end
of which engages the teeth.or notches in the wheel Y. Normally this pawl is thrown
down horizontally upon the frame D, but whenever it is desired to lock the drum.fast
it is moved into engagement with it, as shown in Fig. 9.
In Fig. 1, Z is a windlass barrel, or winch, which is fastened upon the rear end of
the shaft A, outside of the fixed frame.
Figs. 13 and 14 illustrate a modification of my invention, which I will now
describe. Fig. 13 is a longitudinal mid-section cut in the plane of the line 13-13

page_text: Fig. 14; and Fig. 14 is a transverse section there of cut in the plane of the
line 14-14 therein.
A is the driving shaft, B is a carrier fixed thereon, and C is the winding drum. In
the construction before described, the flange a was formed on the part B and the
friction ring E was carried by the part C. In this construction, however, this
arrangement is reversed. The flange a is formed on the drum C, and the friction
ring is carried by the carrier B, which as here shown is not a gear wheel. The
friction ring is divided into three sections, instead of two, and a considerable portion
of the ring is removed between these sections, so that the sections are reduced to the
semblance of friction blocks, or brake shoes, which are lettered E' E'. The carrier B
is constructed with filling portions B B' which fill the spaces between the
sections E E. The carrier B is formed with three radial slide-ways in which the
blocks or sections E' are fitted, the latter being thus capable of moving out and in
radially, being guided by these slide-ways. The knee-piece Hand grooved sleeve L,
are both constructed in one piece connected by a portion 1, and slide upon the shaft A,
with which they revolve. There are three toggle-arms I, one to each ring
section E, and each arm is socketed at one end in a socket in the section E¹,
and at the other end in a socket in the knee-piece, and is pivoted to both
the section and the knee-piece by pins or pintles jj. GG are retracting springs
which are interposed between the carrier B and the knee-piece H, and act to force the
latter to the left, thus pulling back the toggle-arms I, I, and the sections E' E.
B is a cap or hood for enclosing and concealing the clutching parts. The clutch is
applied by means of a hand lever S, which is forked at its fulcrum and carries pins
or rollers, which engage the groove / in the sliding sleeve. In operation, the friction-
ring sections EE are forced outwardly against the flange a by the thrust of the
knee-piece, H, acting through the toggle-arms II, and are drawn back by the tension
of the springs G G.
My invention may be otherwise variously modified in construction, as will be well
understood. It is obvious that either of the respective parts BC may constitute the
driver, it being immaterial whether the power is transmitted from the friction ring
to the flange, or from the latter to the friction ring.
I do not claim broadly the use of toggle-levers for expanding a divided friction
ring, as attempts have been heretofore made to utilize the toggle principle for this
purpose. The success of my clutch is due to the unyielding mounting of the toggle-
arms, which instead of being pivoted or hinged to the ring and knee-piece have their
ends confined in sockets and abutting directly against the solid metal of the ring and
knee-piece. The toggles are also made of broad plates, so that the pressure is
distributed over as wide an area of the ring as possible. The equal radial arrange-
ment of four toggles as shown in Fig. 2, two against each of the two sections of the
ring, is also an important improvement.
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. In a friction-clutch, a divided friction-ring, a knee-piece, and radial toggle-arms
arranged with their opposite ends entering sockets in said ring and knee-piece, and
bearing directly against them, so that on forcing said knee-piece forward, the toggle-
rns are unyieldingly thrust outward, and the friction-ring is expanded into close
rictional contact with the overhanging flange within which it is arranged, substantially
s set forth.
2. In a friction-clutch, the combination with the divided friction-ring and the knee-
iece, formed with opposite sockets, of the radially-arranged toggle-arins consisting
ach of a broad plate, and their opposite ends confined in said sockets, substantially
s set forth.
3. In a friction-clutch, the combination of a friction ring divided diametrically into
wo sections, a knee-piece, and four radial toggle-arms with their inner ends socketted
a said knee-piece, and their outer ends bearing against the ring, two against each

page_text: section thereof, so that the expansive pressure of said toggles is exerted against each
section in two radial directions, substantially as set forth.
4. In a friction-clutch the combination with two rotary parts, one of them forme.
with an overhanging flange, of a friction-ring within said flange, divided diametrically
into two sections, and connected to the other of said rotary parts by means of carrying
pins therein entering sockets in the middle of the sections, a knee-piece, and four
radial toggle-arms having their inner ends socketted in said knee-piece, and their
outer ends bearing against said ring, two against each section, and on opposite sides
of said carrying pins, substantially as set forth.
5. The expanding friction ring E consisting of two diametrical sections con-
nected together by means of guiding devices and provided with springs G G to draw
the sections together.
6. The combination with the divided friction-ring, the knee-piece, and the toggle-
arms, of the socket-blocks J J for receiving the ends of the toggles.
7. The combination with a friction-clutch wherein a divided ring E is expanded by
the action of toggle-arms, I, I, forced outward by a knee-piece H, of the mechanism for
applying the clutch consisting of a grooved sliding sleeve I connected to said knee-
piece, a slide P engaging the groove in said sleeve, and a screw R for propelling said
slide.
..S. The construction of friction clutches, substantially as hereinbefore described and
represented in the accompanying drawings.