Improvements in the Construction of Friction Clutches.
Year: 1891

page_text: Date of Application, 31st Jan., 1591
Complete Specification Left, 30th Oct., 1891-Accepted, 19th Dec., 1891
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Friction Clutches.
I HAROLD WAITE RICHARDSON of 57 Walmsley Street Hull in the County
of York, Engineer do hereby declare the nature of this invention to be as
follows:-
My invention relates to the construction of friction clutches, which may be applied
to any existing pulley or wheel made of any metal.
On the inside of any suitable wheel to be driven I attach by bolts, or other
suitable means a false friction ring of any suitable metal, which may be magnetized
or have attached to it a covering of leather or other frictional material as desired.
Keyed to the shaft to be connected is a metal boss of suitable shape to carry
the centres or pivots of two friction arms or segments which abut against the
inner friction ring. These friction arms are arranged at one end with eccentrically
shaped pivotting pieces, moving on fixed pins placed near together in the boss, and
are adjustable as to the amount of their eccentricity.
Their opposite ends are connected by a right and left handed screw, the
extremities of which are received in loose nuts placed in recesses in the arms so
as to allow the screw to work freely. In the centre of this screw I form a boss,
which is recessed in eight or other suitable number of places around its circum-
ference for attachment to a claw lever, which can be moved round the boss to any
required angle to allow for the wear upon the arms or friction ring.
To prevent the arms having any lateral motion, a covering plate, or plates
is bolted to the boss of the apparatus.
When the lever is moved by any suitable means, the screw is turned and the
friction arms drawn together and moved clear of the friction ring simultaneously
throughout their whole length. In place of the right and left handed screw 1
may substitute the following arrangement.
I attach to the end of one arm a fixed pin which fits into a corresponding
coupling attached by a collar to the other arm. On this fixed pin I arrange a
projection working in an inclined slot in the coupling which has the effect of
drawing the arms together, when the coupling is turned by means of a lever to
which it is attached.
By the above method of placing a ring between the rim and the friction arms
I am able to compensate for wear and tear by renewing the false ring, instead
of the friction arms or outer rim of the pulley or other wheel to which the
apparatus is attached. The use of the friction ring also enables my clutch to be
placed in connection with wheels made of any metal which is unsuitable for
frictional purposes. By allowing the arms to move eccentrically I obtain a better
contact with the friction ring at the base of the arms, and when the friction grip
is taken off, the arms are entirely out of contact with the friction ring.
Dated this Twenty-eighth day of January 1891.

page_text: COMPLETE SPECIFICATION.
Improvements in the Construction of Friction Clutches.
I, HAROLD WAITE RICHARDSON, of 57 Walmsley Street, Hull, in the County
of York, 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 :-
My invention relates to the construction of friction clutches which may be
applied to any existing pulley, or wheel made of any metal.
Hitherto in friction clutches the friction has been obtained from a split ring; this
arrangement presents certain objections, among which may be noted, that both
pieces to be connected must be in perfect line with each other, otherwise there is a
rubbing between the two surfaces, when out of gear.
The object of my invention is to construct a friction clutch whereby such
disadvantages as the aforesaid are obviated.
DESCRIPTION OF DRAWINGS.
Fig. 1, is an elevation, partly in section, showing friction clutch or coupling in
accordance with my improvements.
Fig. 2, is an elevation, partly in section, of modified friction clutch or coupling
in accordance with my improvements.
Fig. 3, is a section of the modified friction clutch or coupling shown in Fig. 2,
in the direction of the length of the shaft.
Figs. 4, 5, and 6, show details of modified incans which may be employed for
expanding the friction arms or segments as shown or arranged in Fig. 1.
Fig. 7, is an elevation of sliding block or sleeve, as shown in Fig. 3.
Fig. 1, and the detail views thereof :-
On the inside of any suitable wheel A to be driven, I attach by bolts or set-
screws B, or other suitable means, a false friction ring C, made of any suitable
metal, but preferably of steel or copper. The friction ring may have attached to
it a covering of leather or other frictional material. Keyed to the shaft D, to be
connected, is a metal boss E to carry the centres or pivots F of two friction arms
or segments G, which abut against the inner friction ring C. The pivots F of the
said friction arms or segments being arranged or constructed eccentrically, (as will
be seen on referring to Fig. 3, of the drawings).
The opposite ends of the said friction arms or segments are connected by a right
and left handed screw J, the extremities of which are received in loose nuts K
placed in recesses I in the friction arms or segments.
In the centre of the said screw J is a boss N which is recessed or notched in
eight or other suitable number of places around its circumference, for engaging
with a claw or forked lever O having projections or squares to engage with the
recesses or notches and being capable of being moved round the boss to any
required angle to allow for the wear upon the said arms or segments or false
friction ring.
To prevent the friction arms or segments having any lateral motion a covering
or plate P is bolted to the boss E, or may be cast with the boss in one piece.
On applying force to the lever O, (in order to remove the friction) the screw J
is turned and the friction arms or segments G drawn together and moved clear of
the friction ring C simultaneously throughout their whole length; in order to
apply the friction the reverse action takes place.
In Leu of the right and left handed screw as above set forth, I may employ
the following arrangement
I attach to the end R (see Fig. 6,) of one of the friction arms or segments G¹
a pin S which fits into a coupling T attached by a collar U to the other friction

page_text: arm or segment G³. On the pin S is a projection V working in an inclined or
quadrant slot W in the coupling T, which has the effect of drawing the arms
together when the coupling is turned by means of the lever X, to which it is
attached.
Or I may employ a wedge X' such as shown in Figs. 4 and 5 (in which Fig. 5,
is an elevation and Fig. 4, a plan) for expanding the friction arms or segments G.
By the above method of placing a ring between the outer rim and the friction
arms or segments I am able to compensate for wear and tear by renewing the false
friction ring instead of the friction arms or segments or outer rim of the pulley or
wheel to which my said improvements may be applied.
The use of the false friction ring also enables my clutch to be employed in con-
nection with wheels or pulleys made of any metal which is unsuitable by itself
for frictional purposes.
By causing the friction arms or segments to move eccentrically I obtain a better
contact with the false friction ring at the base of the said arms or segments, and
when the friction grip is taken off, the said arms or segments are entirely out of
contact with the false friction ring.
Figs. 2 and 3, and the detail view thereof :-
In this modification the false friction ring is dispensed with and the frictional
arms or segments are brought to bear direct upon the pulley or wheel A. The
pivots F of the said frictional arms or segments are eccentrically arranged or con-
structed, as in Fig. 1, and the said frictional arms or segments are connected to
the boss E by means of such pivots. The boss E is keyed upon the shaft D, upon
which is also a sliding block or sleeve Z, to which is attached a link Z', which is
connected to the friction arms or segments G, by means of additional link Z'
which is upon or connected to a boss Z having right and left hand screws Z', the
ends of which are eccentrically pivotted, by pins M, to the said friction arms or
segments, the pins M being constructed similar to the pivots F.
By moving the sliding block or sleeve Z upon the shaft D by any suitable
mechanical appliance, the clutch is put in or out of action.
By using the friction arms or segments G and working them eccentrically by
means of the eccentric pivots I gain a leverage which it is impossible to obtain by
an expanding ring, as the said arms or segments bite at the bottom first, thereby
obtaining the whole leverage of the said arms or segments. I also obtain a greater
amount of adjustment by means of the eccentric pins fixed at both ends of the
friction arms or segments.
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 friction clutches, the employment of false friction rings in combination
with friction arms or segments, operating as and for the purposes such as shown
and described.
2. In friction clutches, the employment of friction arms or segments eccentrically
pivotted at their lower extremities, as and for the purposes such as shown and
described.
3. In friction clutches, the combination of false friction rings C, and friction
arms or segments G, eccentrically pivotted to bosses E, and capable of being
operated as and for the purposes such as shown and described.
4. A friction clutch having arms or segments eccentrically pivotted at their
lower ends to a boss, and at their top ends capable of being expanded or contracted
by means of right and left hand screws (or the equivalent thereof), which are or
may be eccentrically pivotted to the said friction arms or segments, in combination
with a sliding block or sleeve for imparting the requisite contracting or expanding
movement to the said friction arms or segments, substantially as shown and described
with reference to Figs. 2 and 3 of the drawings annexed.
5. In friction clutches, having friction arms or segments such as shown and

page_text: described, the employment of eccentric pins at the tops of such arms or segmen
as a means of adjustment for taking up the wear upon the screws and arms or
segments, substantially as set forth.
Dated 29th October 1891.
JOHN E. WALSH,
Gough Chambers, Saville Street, Hull, Agent for the Applicant.