Improvements in Friction Clutches.
Year: 1892

page_text: Date of Application, 25th Nov., 1892
Complete Specification Left, 17th May, 1893-Accepted, 17th June, 1893
PROVISIONAL SPECIFICATION.
Improvements in Friction Clutches.
I, LOUIS IRVING SEYMOUR, of Kimberley, in the Colony of the Cape of
Good Hope, Engineer, do hereby declare the nature of this invention to be as
follows:
This invention relates to friction clutches for throwing machinery into and out
of motion. My said improved friction clutch may be applied externally or
internally to the wheel or pulley proposed to be set in, or released from, motion.
The external band friction clutch comprises a disc or pulley of cast iron or other
suitable metal or material turned truly on its external friction surface and keyed
firmly to one end of a shaft. Another shaft which may be the driving shaft or the
driven shaft fits loosely in a bush in the said disc or pulley. An arm keyed on the
last named shaft carries on at its outer end a short shaft or spindle on one end of
which are formed or fixed two small pins which act as cranks. To these pins the
ends of the brake band are attached. The brake band may be lined with wood or
other suitable material as is usual. On the other end of the said short shaft or
spindle is keyed a swinging arm or lever which has at its free end a socket in
which fits the ball end of another arm that is pivoted to the sliding sleeve of the
clutch. The said sleeve is operated by the usual strap and lever to put the clutch
in and out of action. One end of the brake band is formed with a lug to which an
be
eye bolt is adjustably secured by lock nuts whereby the length of the band may
adjusted to compensate for wear. The operation of my improved clutch is as
follows, when the sliding sleeve is pushed towards the disc or pulley, it operates
the arms above described in such manner as to turn the short shaft or spindle
carrying the pins and thus draw the ends of the band together with a gradually
increasing leverage which has the effect of tightening the brake band on the pulley.
The tightening is effected gradually at first, thus avoiding jerking, but when full in,
the pulley is gripped with great force.
The internal band friction clutch is similar to that above described with the
exception that instead of having crank pins to draw in the friction band, one end of
the said band is secured to the arm carrying the operating levers, and the other
end is provided with an adjustable screwed pin or the like the end of which fits in
a socket in a short arm or in the hub of the swinging arm or lever, so that when
the said lever is turned about its pivot the internal brake band is thereby expanded
tightly against the inner face of the rim of the friction pulley.
Dated this 25th day of November 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.

page_text: COMIDELE DI PITICATION.
Improvements in Friction Clutches.
I, LOUIS IRVING SEYMOUR, of Kimberley in the Colony of the Cape of
Good Hope, 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 :-
This invention relates to friction clutches for throwing machinery into and out
of motion.
My improved friction clutch may be applied externally or internally to the wheel
or pulley proposed to be set in or released from motion. Both methods of applying
the said clutch may more clearly be described by the aid of the annexed drawings
in which
Figure 1 is a central section of an external band friction clutch constructed
according to this invention, and
Figure 2 is a front view of the same.
Figures 3 and 4 are similar views of an internal band friction clutch.
Like letters indicate corresponding parts in all the figures.
An
Referring to Figures 1 and 2, A is a disc of cast iron or other suitable material,
turned truly on the external friction surface. B, and keyed firmly to the shaft C.
The shaft D revolves freely within a bush A', fixed in the said disc "A."
arm E, preferably balanced is keyed firmly to the shaft D, and carries on its
onter end a small shaft F, on one end of which shaft Fare fixed or formed two
small pins G to act as crank pins. To these small pins the ends of the brake
band H, which is lined with blocks of wood or other suitable material, is coupled.
On the other end of the shaft F, is keyed a swinging arm I, which has at its free
end a socket in which fits the ball like end of the arm J. The other end of the
arm J is pivoted at J¹, to a sleeve K which can slide on the revolving shaft D and
is operated by the usual strap and lever. One end of the brake band H is formed
with a lug L to which an eye-bolt L' is secured by means of lock-nuts. The said
eye bolt is hooked to one of the pins G. By this means adjustment of the brake
band H can be made to compensate for wear. When the sleeve K, carrying the
rod J is pushed towards the arm E, into the position indicated for example by
dotted lines, it moves the lever I away from the shaft D, and thereby turns the
shaft F, and draws the two ends of the brake band H together with a gradually
increasing leverage, which has the effect of tightening the friction band gradually
at first thus preventing jerking and afterwards tightens the said band with great
force. The brake band H may be lined with any suitable substance or not lined
at all, whichever is most expedient, but wood lining is to be preferred.
In the internal friction clutch shown in Figures 3 and 4 the construction and
operation are similar to those of the external clutch above described, but instead
of having two crank pins to draw the ends of the brake band together, the following
construction is adopted, that is to say, one end of the brake band is secured to the
arm E, and the other is provided at L2 with an adjustable screwed pin M, the
end of which fits in a socket provided in the hub or in a short arm of the lever I
as shown in Figure 4. M' is a lock-nut to prevent accidental displacement of the
pin M.
When the sleeve K is pushed towards the arm E, the end of the lever I
is pushed outwards thereby lengthening the internal brake band H or expanding it
tightly against the friction surface which may consist of wooden blocks fastened
inside the rim of the disc or pulley A. The wooden blocks may be fastened either
to the brake band H or to the rim of the disc A. The external and internal
clutches may be applied to an ordinary pulley on a revolving shaft.

page_text: 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 a friction clutch a tightening apparatus which includes the lever I and
arm J, having the ball and socket connection, and operating substantially as
described for the purpose specified.
2. The combination with the lever I and the arm operated by the sliding
collar K, of the brake band H and the adjustable stud or screw pin M, secured in
the band H and resting in a socket in the hub or short arm of the lever I, sub-
stantially as described.
3. A friction clutch constructed substantially as described with reference to
either of the forms shown in accompanying drawings and operating as specified.
Dated this 17th day of April 1893.
LOUIS I. SEYMOUR.
As Witnesses:
H. G. Du PREEY.
P. J. MARSH.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.