Improvements in Friction Clutches.
Year: 1892

page_text: Date of Application, 23rd Jan., 1892
Complete Specification Left, 22nd Oct., 1892-Accepted, 3rd Dec., 1892
PROVISIONAL SPECIFICATION.
Improvements in Friction Clutches.
I, JAMES SALTER FARMER, of Adelphi Iron Works, Salford, in the County' of
Lancaster, Engineer, do hereby declare the nature of this invention to be-as
follows:-
My invention relates to friction clutches employed for driving machinery and the
like.
In constructing a friction clutch according to my invention I dispense with the
usual combination of levers and friction bands, and in their place I employ a fluid
under pressure to operate the clutch.
The casing of the clutch may be in the form of a belt pulley provided with solid
flange sides forming a hollow chamber; the flanges are mounted loosely upon a
boss with arms, which carry a rim, this boss being keyed or otherwise secured to
the shaft of the clutch. Within the chamber formed between the flanges are two
discs of stout leather or similar flexible material, the inner portions of which are
secured one at each side to the inner flange of the rim; and to the sides of the
periphery of the rim the outer portion of each leather disc is secured. One side of
each disc rests close to a prepared or friction surface of one of the side flanges of
the clutch, and the space between the discs forms a chamber which may be filled
with fluid in any convenient manner.
If the clutch is to be placed near the end of a shaft I propose to drill a central
hole up the shaft and connect this hole by a passage leading through the boss into
the chamber formed between the leather discs. When it is desired to operate the
clutch a small quantity of fluid under pressure is admitted through a stuffing box
into the hollow shaft and fluid chamber, thus immediately forcing the discs into
contact with the friction surfaces of the flanges and conveying rotatory motion from
the shaft to the pulley or from the pulley to the shaft as the case may be.
In place of a central hole in the shaft I propose to drill one, two or more holes
up the boss parallel to the shaft and connect these holes by passages leading to the
chamber between the discs; in each hole is fitted a plunger connected at one end to
a sleeve by moving which the fluid could be compressed and the clutch operated.
In order to adjust the side flanges to or from the leather or other discs lock nuts
can be fitted on the boss of the wheel.
If found desirable a thin disc of copper or other metal may be placed on one or
both sides of each leather disc; or as a substitute for the leather discs, two discs
of copper, or other sheet metal may be employed, and such metal discs could be
preferably bent somewhat like a bellows body near where they are secured to the
wheel at its periphery and near its centre.
Dated this 22nd day of January 1892.
H. B. BARLOW,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Friction Clutches.
I, JAMES SALTER FARMER, of Adelphi Iron Works, Salford, in the County of
Lancaster, 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 friction clutches employed for driving machinery and the

page_text: In constructing a friction clutch according to my invention I dispense with the
usual combination of levers. and friction bands, and in their place I employ a fluid
under pressure to operate the friction clutch.
The casing of the clutch may be in the form of a belt pulley provided with solid
flange sides forming a hollow chamber; the flanges are mounted loosely upon a
boss with arms, which carry a rim, this boss being keyed or otherwise secured to
the shaft of the clutch. Within the chamber formed between the flanges are two
discs of stout leather or similar flexible material, the inner portions of which are
secured one at each side to the inner flange of the rim and to the sides of the
periphery of the rim the outer portion of each leather disc is secured. One side of
each disc rests close to a prepared or friction surface of one of the side flanges of
the clutch, and the space between the discs forms a chamber which may be filled
with fluid in any convenient manner.
If the clutch is to be placed near the end of a shaft I propose to drill a central
hole up the shaft and connect this hole by a passage leading through the boss into
the chamber formed between the leather discs. When it is desired to operate the
clutch a small quantity of fluid under pressure is admitted through a stuffing box
into the hollow shaft and fluid chamber, thus immediately forcing the discs into
contact with the friction surfaces of the flanges and conveying rotatory motion from
the shaft to the pulley or from the pulley to the shaft as the case may be.
In place of a central hole in the shaft I propose to drill one, two or more holes
up the boss parallel to the shaft and connect these holes by passages leading to the
chamber between the discs; in each hole is fitted a plunger connected at one end
to a sleeve by moving which the fluid could be compressed and the clutch
operated.
In order to adjust the side flanges to or from the leather or other discs lock nuts
can be fitted on the boss of the wheel.
If found desirable a thin disc of copper or other metal can be placed on one or
both sides of each leather disc; or as a substitute for the leather discs, two discs of
copper, or other sheet metal may be employed, and such metal discs could be
preferably bent somewhat like a bellows body near where they are secured to the
wheel at its periphery and near its centre.
And in order that my invention may be fully understood and readily carried into
effect I will describe the accompanying two sheets of drawings reference being had
to the figures and letters marked thereon.
Fig. 1 is a sectional elevation on the line A B, Fig. 2, and Fig. 2 is a front view,
one half being in section, of my improved friction clutch, and Figs. 3 and 4 are
similar views of an alternative construction of the same.
Similar letters refer to similar parts throughout the several views.
Referring first to Figs. 1 and 2,-a represents the shaft or axis to be driven,
b'a clutch pulley fitted near the end of the shaft, which is bored out at a¹ as far as
the centre of the clutch. The pulley has the boss of one side flange & fitted on the
shaft a and a similar flange b2 also loose on the shaft is secured to the flange by
bolts c and a chamber a is thus formed between the said flanges, the inner faces of
which are turned or faced to form friction surfaces. In the middle of the chamber a
and keyed upon the shaft is a wheel d with arms which carry a rim d¹ and also
within the chamber are two stout discs of leather, india rubber or other suitable
material e secured to the wheel d and its rim d¹ by screws ff which pass through
washers g g'. A thin disc of steel or copper his by preference placed on the outer
side of each disc e between the latter and the friction surface f on the flange; these
metal discs have projections ¹ on their outer periphery which enter suitable
recesses in the washer gl, see Fig. 2, and are thereby rotated with the wheel d and
disc e, and in order to adjust the flanges & 6 to or from the discs h, lock nuts jj¹ are
fitted on the shaft.
To convey rotary motion from the driven pulley to the shaft a water or other
fluid under pressure is admitted through a stuffing box, not shown, at the end of the
shaft a into the opening a¹ through which it enters by a pipe or passage
the

page_text: chamber between the flexible discs e and gradually forces these discs against.
the metal discs h, which are thereby brought into contact with the prepared faces
of the driven flauges ; as soon as the pressure of the liquid is sufficiently great
for the friction between the flanges of the pulley and the discs h to overcome the
inertia of the shaft a the latter will be set in motion and continue to rotate so long
as the pressure of liquid is maintained and the pulley continues to be driven.
To stop the shaft it is only necessary to shut off the fluid which is preferably
controlled by a two-way valve or equivalent so as to allow a small quantity of the
Huid in the chamber to escape and thus relieve the pressure in the chamber.
In Figs. 1 and 2 the pulley b is shown mounted to run loose upon the shaft a, it-
might however, be mounted on the boss of the wheel d in which case the boss of the
wheel d would have to be made longer as shown in Figs. 3 and 4.
In Figs. 3 and 4 the wheel d which carries the friction discs e has a long boss, on,
which the driven pulley is fitted.
In the boss of the wheel d are two small
holes parallel with the axis of the wheel and communicating by holes with the
chamber and in each of these holes d² is fitted a plunger k, the plungers passing
through stuffing boxes and are jointed to a sleeve m fitted to slide upon the shaft
and arranged to force the plungers into the holes d².
2:
In applying this clutch the hollow chamber a between the discs e is filled through
a hole y with any suitable fluid at a time when the plungers are drawn back, but
as shown in Fig. 3, not out of the holes d, the hole y through which the fluid has
been poured into the clutch is then closed, and then by forcing the plungers into the.
holes and so putting pressure on the fluid in the chamber the friction surfaces of the-
clutch are brought together, and rotary motion is thereby communicated from.
the driven pulley to the shaft a until the plungers are drawn back a short distance.
and the pressure relieved.
It is obvious that in either construction Figs. 1 and 2 or Figs. 3 and 4, the
pulley could be driven from the shaft instead of the shaft from the pulley as
described.
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. A friction clutch the friction surfaces of which are forced into and maintained
in contact whilst the clutch is working by fluid under pressure substantially in the
manner herein described.
2. The combination and general arrangement of parts constituting my improved
friction clutch substantially as herein described with reference to Figs. 1 and 2.
3. The combination and general arrangement of parts constituting my improved.
friction clutch substantially as herein described with reference to Figs. 3 and 4.
Dated this 21st day of October 1892.
H. B. BARLOW,
17, St. Ann's Square, Manchester, Agent for Applicant.