Improvements in Apparatus applicable for Coupling or Uncoupling Shafts, Driving Pulleys, Wheels, or the like.
Year: 1890

page_text: Date of Application, 2nd Oct., 1890-Accepted, 8th Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Apparatus applicable for Coupling or Uncoupling
Shafts, Driving Pulleys, Wheels, or the like.
A communication from abroad by SILVIC DE PRETTO, of Schio, Vicenza, in the
Kingdom of Italy, Civil Engineer.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in
the County of Lancaster, and 323, High Holborn, in the County of Middlesex, Civil
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 a shaft coupling adapted to allow two power shafts or the
like to be connected with, or disconnected from one another without stopping the
engine. If the coupling be applied to a pulley, it enables it to be made fast or loose
on the shaft without stopping the engine or removing or displacing the belt.
It is applicable equally well to couplings connecting the ends of two driving shafts,
as to a pulley or gearing for transmitting power.
On the drawings accompanying this Specification
Figures 1, 2 and 3 represent respectively,
A longitudinal section,
A transverse section, and
A side elevation,
:-
Of the friction coupling connecting ends M and N of two driving shafts with one
another. This coupling is composed of four principal parts D, E, F, R. The barrel D
is fixed by a key on the axle M. The part E, having the shape of a plate, is fixed on
the axle N in the same manner. The friction clutch F is an elastic metal ring which
has a breach of continuity (that is, split) at the point x, and carries two idle
rollers a b as well as two appendices c d. In its normal state, the diameter of the
exterior cylindrical surface of this ring is less than that of the barrel D; but if, by
means of a wedge inserted between the rollers a b, a strain be produced, the ring
opens sufficiently to allow of its external surface fitting exactly within the interior of
the barrel D. The plate E has a projection k, which, inserting itself between the two
appendices cd of the clutch, obliges the latter to take part in the rotary motion of
the shaft N.
The sleeve R receives a rotary motion from the shaft by means of the feather
which allows it to receive simultaneously a longitudinal motion along the shaft,
approaching or receding from the plate E.
This lateral motion is brought about by a forked lever, which engages the groove 1,
and which is not shown in the drawing, as can have various forms according to
circumstances. This sleeve has a wedge shaped bolt e, which, traversing a hole in
the plate E, intervenes between the two rollers a b, forcing the clutch F to open and
close (by its elasticity) according to whether the sleeve approaches or retires from
the plate E.
The mechanism can be studied in the two following cases, namely
1st. When the sleeve is forced to approach the plate E. In this case the clutch F
expands, pressing against the interior surface of the barrel D and producing enough
friction to unite the two parts D and E firmly one with another.
Consequently if one of these two shafts rotates, the other one must, rotate at an
equal speed.
2nd. When the sleeve is forced to recede from the plate E. In this case the spring
clutch F contracts by virtue of its elasticity, and the ring and barrel D being thereby
deprived of the friction which held them together, the two shafts become disconnected

page_text: from one another. Then in order to prevent any friction, the ring F, contracting,
places itself on the projecting tooth S round the plate E and maintains its position
there by reason of its elasticity.
This new apparatus can be also applied to a pulley as shown by Figures 4 and 5,
without changing anything in its parts.
For a pulley, the construction and mode of working are exactly identical with what
has been described, and it is easy to understand that, in the same manner, a pulley
can be made loose or fast on a shaft even while in action.
The same can be applied to transmission gearing, straight or bevelled.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what 1 claim is :-
1. An apparatus for coupling and uncoupling shafts, driving pulleys, gearing wheels
or the like without stopping the engine or displacing or removing the belt, consisting
essentially of an elastic friction clutch ring and of a cylindrical barrel R, against the
interior periphery of which the said clutch expands or contracts under the action of a
sliding bolt or the like, and thereby respectively binds the two parts firmly one with
the other, or releases them, substantially as described.
2. The hereindescribed arrangement of parts forming the apparatus for coupling
and uncoupling shafts, driving pulleys, gearing wheels or the like, substantially as
described.
Dated this 1st day of October 1890.
WM. P. THOMPSON & Co.,
Agents for the Applicant.