Improvements in the Means for Actuating Friction Clutches or Couplings.
Year: 1896

page_text: Date of Application, 7th Dec., 1896
Complete Specification Left, 24th Aug., 1897-Accepted, 20th Nov., 1897
PROVISIONAL SPECIFICATION.
Improvements in the Means for Actuating Friction Clutches or
Couplings.
I, WILLIAM EDWARD BUCK of 21 Herbert Street Moss Side Manchester do hereby
declare the nature of this invention to be as follows:-
This invention relates to improvements in the means of actuating or putting into
gear mechanisms well known as friction clutches & is applicable to any of such
clutches in which the power for putting into gear is applied at two points or is
divided into two portions.
Friction clutches are many & various in form & design but most of them consist
essentially of an internal drum or disc & an external ring or coil, or of an external
ring and internal segments or coil. One of such members is attached to the
driving shaft & its complementary member to the driven shaft or to a pulley or
wheel & the surfaces of the drums, discs, rings or coils, being brought gradually
into contact, friction ensues between them and increases until it overcomes the
inertia of the driven part and the driven & driving parts revolve together &
transmit the necessary power along the shaft or to the pulley or wheel.
In many of these devices it is desirable that the. power for bringing the before
mentioned parts or surfaces of such parts into contact should be applied at two
different points generally on opposite sides of the shaft, both for convenience &
compactness of design & also that the links, levers, screws, cams, toggles or other
mechanism employed for the purpose should balance one another.
It is of great importance that the power thus divided should be applied equally
at the two points of resistance as otherwise one part of the clutch will be forced
into closer contact than the other & the clutch will not act with its full efficiency
while unequal wear of the friction surfaces will also take place.
The object of this invention is to ensure such equality of power or pressure &
to effect it I provide that the two screws, cams, wedges, toggles, levers or whatever
similar devices be employed to expand or contract the frictional surfaces of the
clutch shall be connected in any suitable manner to the two equal arms of a lever
or scalebeam which is pivotted at its centre to the ring or sleeve, which ring or
sleeve being generally actuated by a lever, screw or other device, slides longi-
tudinally on the shaft & gives motion to the parts of the clutch.
Such lever or scalebeam of equal arms may be of any convenient form &
generally I prefer that it shall be in the form of a ring or gimbal which embraces
part of the sliding ring or sleeve to which it is pivotted on its transverse axis while
two opposite points on its vertical axis carry the links for actuating the clutch.
I do not limit myself however to this form & may employ any device or arrange-
ment having equal arms & a central pivot whereby the pressure applied at the
pivot is transmitted in two equal portions through the two equal arms.
Should one arm meet with preponderating resistance its movement will be

page_text: arrested until the opposite arm moves forward & encounters identical resistance.
It will thus be seen that whatever pressure is applied to the sliding ring or sleeve
must necessarily be transmitted with exact equality to the two opposite screws,
cams, levers, toggles or other devices employed for contracting or expanding the
frictional surfaces of the clutch.
Improvements in the Means for Actuating Friction Clutches or
Couplings.
I, WILLIAM EDWARD BUCK Engineer, of 21 Herbert Street Moss Side Manchester
& of the Unbreakable Pulley & Millgearing Company Ltd. of Manchester 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 improvements in the means of actuating or putting
into gear mechanisms well known as friction clutches & is applicable to any of
such clutches in which the power for putting into gear is applied at two points
or is divided into two portions.
Friction Clutches are many & various in form & design but most of them consist
essentially of an internal drum or disc and an external ring or coil or of an
external ring & internal segments or coil. One of such members is attached
to the driving shaft & its complementary member to the driven shaft or to a
pulley or wheel, & the surfaces of the drums, discs, rings or coils being brought.
gradually into contact friction ensues between them and increases until it over-
comes the inertia of the driven part and the driven and driving parts revolve
together and transmit. the necessary power along the shaft or to the pulley or
wheel.
In many of these devices it is desirable that the power for bringing the before-
mentioned parts or surfaces of such parts into contact should be applied at two
different points generally on opposite sides of the shaft both for convenience and
compactness of design and also that the links, levers, screws, cams, toggles or
other mechanism employed for the purpose should lalance one another.
It is of great importance that the power thus divided should be applied equally
at the two points as otherwise one part of the clutch will be forced into closer
contact than the other and the clutch will not act with its full efficiency while
unequal wear of the friction surfaces will also take place.
The object of this invention is to ensure such equality of power or pressure and
to effect it I provide that the two screws, cams, wedges, toggles, levers or whatever
similar devices be employed to expand or contract the frictional surfaces of the
clutch shall be connected in any suitable manner to the two equal arms of a lever
or scalebeam which is pivotted at its centre to the ring or sleeve which ring or
sleeve being generally actuated by a lever, screw or other device slides longi-
tudinally on the shaft and gives motion to the parts of the clutch.
Such lever or scalebeam of equal arms may be of any convenient form and
generally I prefer that it shall be in the form of a ring or gimbal which embraces
part of the sliding ring or sleeve to which it is pivotted on its transverse axis
while two opposite points on its vertical axis carry the links for actuating the
clutch.

page_text: I do not limit myself however to this form and may employ any device or
arrangement having equal arms and a central pivot whereby the pressure applied
at the pivot is transmitted in two equal portions through the two equal arms.
Should one arm meet with preponderating resistance its movement will be
arrested until the opposite arm moves forward and encounters identical resistance.
It will thus be seen that whatever pressure is applied to the sliding ring or sleeve
must necessarily be transmitted with exact equality to the two opposite screws,
cams, levers, toggles, or other devices employed for contracting or expanding the
frictional surfaces of the clutch.
Having thus described the nature of my invention I will proceed to describe one
manner of carrying out the same as shown on the drawing attached.
Fig. 1 is a sectional elevation of a friction clutch with the sleeve or sliding piece
for actuating it shown in full elevation. Fig. 2 is a front elevation of the clutch
with the sleeve removed. Fig. 3 is a front elevation of the sleeve and links and
Fig. 4 is a side elevation of the sleeve shown at a point midway in its travel and
with the ring or gimbal canted.
In Figs. 1, 2 and 4, A is the body of a friction clutch with B B. the friction
blocks which are moved inwards or outwards into contact with A. A. along the
arms of the driving piece C which is keyed on the shaft. The blocks Bare
moved outwards or inwards by the right and left handed screws DD working in
suitable nuts secured in the blocks. The screws are rotated by their lever
arms EE which in their turn are actuated by the links FF connected to the
pivotted ring or gimbal G carried on the sleeve or slide H which is mounted on
the shaft and moved by a hand lever or screw or in any suitable manner.
The dotted lines in Fig. 1 show the sleeve in its reversed position with the arms
of the screws drawn outwards. When in this position the blocks BB will be
drawn inwards by the screws 1) 1) and will be out of contact with A A which will,
in consequence, remain stationary on the shaft. On sliding the sleeve from the
dotted to the full position in Fig. 1 the screws will be rotated in the reverse
direction by means of their arms EE and the links FF and the blocks BB will
be forced out against A causing the latter to rotate by the friction between the
surfaces. If, during the rotating of the screws, one of them should meet with
more resistance than the other, owing to slight inequalities in wear or workmanship,
then the link attached to the arm of that screw will remain more or less stationary
and the motion imparted to the sleeve H will be transmitted wholly to the other
link and screw, the gimbal or pivotted ring G meanwhile taking a canted position
as shown in Fig. 4 until the pressure on the blocks is equal, when both screws
will be again rotated simultaneously.
The differential motions of the two screws thus described may be almost imper-
ceptible, but it will be seen that the pressure transmitted by one must be exactly
equal to that transmitted by the other as, by means of the pivotted ring or
gimbal G, one block B3 practically forms the fulcrum or point of resistance or
reaction for the other.
It will be seen that the application of such ring or gimbal G need not be confined
to a clutch actuated by screws or of the form shown but may be extended to any
clutch or frictional driving device wherein it is desirable to apply the power for
putting it into gear in two places or by means of two' screws, levers, wedges, cams
or toggles. It will also be obvious that the exact form of ring or gimbal G need
not be adhered to as any arrangement of centrally pivotted levers or scalebeam
will effect the same result.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is
1. The application to any friction clutch wherein the power for putting into gear
is applied at two points or in two places of a scalebeam, gimbal or ring mounted
and centrally pivotted on a sliding sleeve and having the ends of its equal arms or

page_text: extremities connected to the two levers, cams, screws, toggles or other devices
whereby the clutch is put into gear.
2. The arrangement of ring or gimbal and friction clutch shown in the drawings.
Datad this Twenty third day of Avant 1807