Improvements in the Construction of Friction Clutches.
Year: 1895

page_text: Complete Cannif
Date of Application, 7th Dec.. 1895
1
A
2000
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Friction Clutches.
I, FREDERICK LISTER CROFT, of the Great Northern Works, Leeds Road,
Bradford, in the County of York, Millwright, do hereby declare the nature of this
invention to be as follows:
This invention relates to certain improvements in friction clutches for trans-
mitting rotary motion from one shaft to another, or from a rotating pulley or the
like to a shaft, and has for its object, the construction of the clutches in such a
manner that, when the friction ring or driving box expanded in the shell or
pulley of the clutch, the back or outward pressure on the sliding sleeve is entirely
or in a great measure obviated; also to so construct the friction ring or driving
box that the entire circumference of each section of the said ring is brought into
contact or removed from the shell or pulley of the clutch on the operation of the
sliding sleeve, and to so mount the levers of the expanding gear, that they are
locked in the required position when the friction ring or driving box is disengaged
with the shell or pulley of the clutch.
In carrying out my object, I construct the friction ring or driving box with
curved arms, connecting the boss and circumference of the ring which is divided
in two places opposite to each other.
The expansion and contraction of the ring is accomplished by right and left hand
threaded screws engaging with nuts mounted in the said ring, the screws being
operated by levers connected to the sliding sleeve. Two of the said levers are
provided with adjusting screws so arranged that, the length of the levers can be
readily regulated to such a length that, when the friction ring or driving box is
expanded these levers are in a vertical position, and thus remove all back or
outward pressure from the sliding sleeve.
In order to retain the friction ring or driving box in its required position when
disengaged with the shell or pulley of the clutch, I mount in the boss of the said
friction ring, two studs having the outer ends cut to an angle, which when the
friction ring or driving box is withdrawn from the shell or pulley, engage with
corresponding recesses cut in the levers engaging with the before mentioned
screws.
In arranging friction clutches suitable for attachment to a rotating belt or other
pulley or wheel so that there is no back or outward pressure on the sliding sleeve when
the clutch is in gear, 1 secure to the pulley or the like a circular plate, and cover same
with another plate in a manner that there is a recess between the two, the last
mentioned plate supporting the operating levers for applying pressure to the
frictional part of the clutch which is composed of two or more plates mounted in
the before mentioned recess.
A sliding sleeve is mounted on the shaft and on moving same in the direction for
expanding the levers, the ends of the latter travel up an incline on the sleeve, to a
parallel portion, where they rest without any back or outward pressure being on
the sliding sleeve.
When the levers are operated in the manner described, one of the plates mounted
in the before mentioned recess is operated and the other plate or plates pressed
tight between the same and the first mentioned plate, that is the oue secured to the
pulley or the like, thus by these means a friction clutch is constructed in a manner

page_text: that there is no pressure on the sliding sleeve when the frictional parts are in
contact.
Dated this 5th day of December 1895
JOHN WAUGH,
Agent.
Improvements in the Construction of Friction Clutches.
I, FREDERICK LISTER CROFT, of the Great Northern Works, Leeds Road,
Bradford, in the County of York, Millwright, 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 certain improvements in friction clutches for transmitting
rotary motion from one shaft to another, or from a rotating pulley or the like to a
shaft, and has for its object, the construction of the clutches in such a manner that
when the friction ring or driving box is expanded in the shell or pulley of the
clutch, the back or outward pressure on the sliding sleeve is entirely or in a great
measure obviated; also to so construct the friction ring or driving box so that the
entire circumference of each section of the said ring is brought into contact or
removed from the shell or pulley of the clutch on the operation of the sliding
sleeve; and to so mount the levers of the expanding gear that they are locked in
the required position when the friction ring or driving box is disengaged with the
shell or pulley of the clutch.
In describing my invention in detail, reference is made to the accompanying
drawings in which
Fig. 1. represents a section of a friction clutch constructed according to my
invention.
Fig. 2. is a front view of the same with the levers, ordinary cover plate, and
sliding sleeve removed.
Fig. 3. is an elevation in section of a clutch suitable for attachment to a pulley
wheel or the like and
Fig. 4. is a front view of the same with the bracket, sliding sleeve, and levers
removed.
In carrying out my object with clutches of the description shown by Figs. 1.
and 2. I construct the friction ring or driving box with curved arms A. connecting
the boss B. and circumference C. of the ring, which is divided in two places D. D.
opposite to each other.
The expansion and contraction of the said friction ring is accomplished by right
and left hand threaded screws E. engaging with circular nuts F. mounted in some
convenient portion of the said friction ring, the threaded screws E. being operated
by levers G. connected to the sliding sleeve H. by arms J. so arranged that the
length of the arms can be adjusted by the respective screws K. in order that when
the friction ring or driving box is expanded into frictional contact with the
internal circumference of the shell L. of clutch, the arms J. are in a vertical
position that is at right angles to the axis of the shaft, thus removing all back or
outward pressure from the sliding sleeve H.
The bosses M. of the levers G. are each fitted with a screw N. and serrated
die O. for positively connecting the said levers to the screws E. and in order to
retain the friction ring or driving box in its required position when disengaged
with the shell or pulley L. of clutch I mount in the boss B. of said friction ring,
two studs Q. having their outer ends cut to an inclination or angle which when the
friction ring or driving box is withdrawn from contact with the shell or pulley L.
engage with recesses cut in the bosses M. of levers G. the compressed spiral
springs R. forcing the studs Q. into the recesses when the latter arrive opposite

page_text: the ends of the said studs. On expanding the friction ring or driving box, the
inclined or angular end of each stud Q. allows the levers G. to be operated, the
studs leaving the holes and compressing the spiral springs R.
In arranging friction clutches suitable for attachment to a rotating belt or other
pulley T. or wheel so that there is no back or outward pressure on the sliding
sleeve S. when the clutch is in gear 1 secure to the pulley T. or the like which is
free to rotate on the shaft V. a circular and recessed plate U. and in front of the
recess I secure to the shaft V. another circular plate W. arranged for supporting
the two levers X. mounted between jaws and connected thereto by fulcrum pins Y.
the levers extending such a distance so as to come in contact with the screws or
projections Z. attached to or forming part of the internal plate 1. between which
and the internal face of circular and recessed plate U. is a friction plate 2.
On the shaft V. a sliding sleeve S. is mounted, and engaging with the latter is a
lever 3. supported by a pin and bracket 4. mounted on the shaft V. or otherwise
as found convenient. On operating the lever 3. in the direction for sliding the
sleeve S. towards the pulley or the like T. the ends of the levers X. travel up the
inclined or curved portion of the sleeve S. to the straight or parallel portion of
the circumference at S' where they rest without applying any back or outward
pressure to the sliding sleeve S.
When the levers X. are operated in the manner described, the extended ends of
the levers force the plates 1. and 2. towards the recessed plate U. thereby pressing
the friction plate 2. between plates U. and 1. to such an extent that the friction
between them is sufficient to cause the pulley or the like T. to rotate the shaft V.
The pulley or the like T. is kept in position on the shaft V. by a collar or other
convenient means and the friction plate 2. may be faced on each side with soft
metal or flexible disc such as leather secured to the said plate.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. The pulley or rim L. of a friction clutch with which is combined a friction
ring having curved arms A. arranged substantially in the manner as hereinbefore
described and illustrated.
2. A friction clutch with which is combined a sliding sleeve H. connected to the
levers G. of the friction ring by adjustable arms J. arranged substantially in the
manner as hereinbefore described and illustrated.
3. A pulley or the like to which is secured or connected a friction clutch
constructed substantially in the manner described and operated by a sliding
sleeve S. having an inclined or curved face for operating the levers X. and a
straight surface S' for the ends of the levers X. to rest upon when the friction
plate 2. is under pressure.
4. A sliding sleeve S. having an inclined or curved face and a straight parallel
or hollow seat S' for supporting the ends of levers X. for the purpose hereinbefore
described.
Dated this 5th day of September 1906.
JOHN WAUGH,
Agent.