IMPROVEMENT IN FRICTION CLUTCHES
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENT IN
FRICTION CLUTCHES." A communication from abroad by William Frederick
Holske and Benjamin Talbot Babbitt, both of the City, County, and State of
New York, United States of America.
Sealed the 17th March 1876, and dated the 7th January 1876.
COMPLETE SPECIFICATION filed by the said Alexander Melville Clark at the
Office of the Commissioners of Patents on the 7th January 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middle-
sex, Patent Agent. "IMPROVEMENT IN FRICTION CLUTCHES." A communication
from abroad by William Frederick Holske and Benjamin Talbot Babbitt, both of
the City, County, and State of New York, United States of America.
This Invention is applicable to machinery of every description, its object being
to facilitate the locking and unlocking of loose pulleys upon the shafts on which
they run.
The Invention consists in the combination of certain locking wedges with the
inner periphery of the pulley, and the outer periphery of a hub which slides longi-
tudinally on the pulley shaft.
Referring to the accompanying Drawing,―
Figure 1 is a side elevation of the improved friction clutch; Figure 2 is a cross
sectional elevation of the same through the line x, x, in Figure 1.
Figure 3 is an end elevation of the sliding hub showing the locking wedges and
their seats; Figure 4 is a plan view of the same.
Similar letters of reference indicate corresponding parts.
A is the pulley shaft; B, the loose pulley; C, the sliding hub, which by the
feather at a is caused to turn with the shaft and permitted to slide longitudinally
thereon; D, D, are the usual stops. The central portion of pulley B is provided
with a hub, one end of which 6 is made of conical form and receives the interior of
the hub C, which is of corresponding form. Lubricating oil is conveyed between
the surfaces of the pulley cone and the hub by oil channel c. E is an annular rim
attached to the side of the pulley A, seated upon the hub C in seats of the form
shown at f, Figure 3. Between the inside of the rim E and the hub C I arrange
one or more locking wedges F, which are provided with beveled teeth g on their
outer surfaces which fit into corresponding beveled cavities upon the inside of the
Duin il

page_text: rim E. The inner surfaces or backs of the wedges F are beveled and provided at
their edges with beveled or inclined feathers or tongues h which fit within corre-
sponding inclined grooves made in the sides of the seats f in the beveled hub C.
At i in the hub C is the usual groove for the fork of the operating lever.
When the hub C is pushed in the direction of the arrows the wedges F by reason
of their inclined tongues, seated within the corresponding inclined grooves in the
hub C, are pushed outward so as to cause their beviled teeth g to press against and
become locked within the corresponding recesses of the rim E, thereby firmly
locking the pulley B and hub C, and causing the pulley to revolve with shaft. But
when the hub C is moved in the contrary direction the wedges F are drawn
inward towards the centre of the pulley and the teeth g are unlocked from the
rim E, leaving the pulley B loose upon shaft A. Thus the lateral movement of
the hub C in one direction pushes the wedges F outward from the centre of the
pulley, and the contrary movement of the hub draws the wedges inward towards
the centre of the pulley, thereby locking or unlocking the pulley B.
In the case of small sized or special pulleys the interior surface of the pulley
periphery takes the place of the rim E, and such surface is provided with bevelled
recesses to receive the teeth g, and in such pulleys I omit the rim E.
Having described the nature of the Invention, and the manner in which the sanie
is to be carried into effect, I would observe that I do not limit or confine myself to
the exact form or position of any of the parts herein shown, as they may be varied
without departing from the Invention; but what I claim as new and desire to
secure by Letters Patent is, the combination of one or more wedges F, pulley B,
and sliding hub C, when constructed and operating together, substantially as herein
shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Seventh day of January, in the year of our Lord One
thousand eight hundred and seventy-