IMPROVEMENTS IN FRICTIONAL CLUTCHES OR BRAKES FOR MACHINERY
Year: 1882

page_text: LETTERS PATENT to Henry Fisher of Nottingham in the county of
Nottingham and John Scarisbrick Walker of Wigan in the County of
Lancaster for an Invention of "IMPROVEMENTS IN FRICTIONAL CLUTCHES OR
BRAKES FOR MACHINERY."
PROVISIONAL SPECIFICATION left by the said Henry Fisher and John
Scarisbrick Walker at the Office of the Commissioners of Patents on the
28th July 1882.
HENRY FISHER of Nottingham in the County of Nottingham and JOHN
SCARISBRICK WALKER of Wigan in the County of Lancaster "IMPROVEMENTS IN
FRICTIONAL CLUTCHES OR BRAKES FOR MACHINERY"
This invention has for its object improvements in the means of engaging and
disengaging shafting, spur, bevel, or other wheels and pulleys used for communi-
cating motion to ropes, chains, belts, bands or any other kind of machinery, and
for any other purpose for which engagements and disengagements are required.
In the various forms of clutches now in use defects of one sort or another render
them unsuitable for the work they are designed to perform In some forms for
instance it is difficult to engage the clutch when the driving shaft is in motion
and to disengage it when the full load is ou owing to the friction on the faces in
contact and when put into gear the machinery is so suddenly set in motion from
a state of rest as to cause dangerous shocks and damage thereto. Others that may
be preferable in some respects are liable to become jammed when thrown into gear
causing great inconvenience when it is required to throw them out of gear again.
Now our invention is designed to obviate these objections and provide a clutch
which we consider is so constructed as to possess the following advantages over
other clutches now in use.
1st That it can be put into gear while the driving shaft is running at full speed.
2nd That it can be put into gear to communicate motion from the driving shaft
to the machinery to be set in motion by a slow and progressive acceleration from
a state of rest to the required velocity, so as to avoid dangerous shocks and
consequent liability to breakage of the machinery.
3 That it can be adjusted so as to move a certain load or overcome a certain
amount of resistance, and if by accidental means, such as breakages or obstructions
to any part of the machinery, additional resistance be communicated to the clutch

page_text: . ¡
it will slip and so indicate that something is wrong with some part of the machinery
when the driving shaft can be stopped and so prevent further damage to the
machinery.
4th That it can be easily and instantaneously thrown out of gear while the
driving shaft is running at full speed.
The driving wheel or pulley to which motion is required to be communicated
from the driving shaft when the clutch. is in gear, is made to run loose on the
driving shaft when the clutch is out of gear so that the driving shaft can rotate if
required and the driving wheel remain at rest.
On the boss of the driving wheel is cast or keyed a disc plate with four or
other number of pins and is made to rotate with the driving wheel when the
clutch is in gear and to remain at rest when the clutch is out of gear.
A friction wheel is keyed on to and made to rotate with the driving shaft.
On this friction wheel is a clip or brake made in four or other number of parts,
both ends of each part of the clip or brake being made with projections through
which are holes chased with screw threads to receive right and left hand threaded
screws.
The projections are preferably made with recesses to receive nuts chased with
screw threads to receive the right and left hand threaded screws.
Each part of the clip or brake is made with a pin hole to receive the pins
attached on the disc plate.
On the right and left hand threaded screws are fixed levers preferably by
pinning which are connected with the arms of a sliding piece which moves freely
on the driving shaft by links.
On this sliding picce is a groove in which a forked or other form of lever works
to move the sliding piece on the driving shaft, but the lever forms no part of this
Invention.
Now according to this Invention when the sliding piece is made to slide on the
driving shaft by a lever in the usual way, motion is communicated to the right.
and left hand threaded screws by the links and levers by which means the clip or
brake opens and allows the friction wheel to revolve freely with the driving shaft
while the driving wheel remains at rest. When the sliding piece is made to slide
on the driving shaft in the opposite direction to that described, motion is communi-
cated to the right and left hand threaded screws by the links and levers to which
they are attached by which means the clip or brake closes and grips the friction
wheel, which being keyed on the driving shaft causes the clip or brake to revolve
with the friction-wheel and driving shaft. and communicates motion to the disc
plate and driving wheel through the disc plate pins.
The right and left hand threaded screws can be so arranged that the clutch can
be put into gear by moving the sliding piece either towards or from the driving
wheel as may be required, and put out of gear by moving the sliding piece in the
opposite direction to that required for putting the clutch into gear.
As the sliding piece can be slid on the driving shaft to communicate motion to
the right and left hand threaded screws either to open or close the clip or brake
both when the driving shaft is at rest or running at full speed, the clutch can be
effectually put into or out of gear as may be required whether the driving shaft is
at rest or running at full speed.
As the clip or brake can be gradually closed to grip the friction wheel by the
gradual motion of the right and left hand threaded screws, motion is gradually
communicated to the driving wheel until it has attained the required velocity.
The clip or brake can be adjusted to grip the friction wheel by the amount of
motion given to the right and left hand threaded screws so as to move a given load
or overcome a certain amount of resistance.
A similar arrangement of right and left hand screws might be used for
tightening the strap of an ordinary strap brake and be used for this purpose instead
of for a clutch.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Fisher and John Scarisbrick Walker in the Great Seal Patent
Office on the 27th January 1883.
HENRY FISHER, of Nottingham in the County of Nottingham and JOHN
SCARISBRICK WALKER, of Wigan in the County of Lancaster "IMPROVEMENTS IN
FRICTIONAL CLUTCHES OR BRAKES FOR MACHINERY 33
This invention has for its object improvements in the means of engaging and
disengaging shafting, spur, bevel, or other wheels and pulleys used for communi-
cating motion to ropes, chains, belts, bands or other kind of machinery, and for any
other purpose for which engagements and disengagements are required.
In the various forms of clutches now in use defects of one sort or another render
them unsuitable for the work they are desired to perform. In some forms for
instance it is difficult to engage the clutch when the driving shaft is in motion, and
to disengage it when the full load is on owing to the friction on the faces in
contact and when put into gear the inachinery is so suddenly set in motion from a
state of rest as to cause dangerous shocks and damage thereto. Others that may
be preferable in some respects are liable to become jammed when thrown into
gear causing great inconvenience when it is required to throw them out of gear
again.
Now our invention is designed to obviate these objections and provide a clutch
which we consider is so constructed as to possess the following advantages over
other clutches now in use:-
1st That it can be put into gear while the driving shaft is running at full speed
2nd That it can be put into gear to communicate motion from the driving shaft
to the machinery to be set in motion by a slow and progressive acceleration from a
state of rest to the required velocity, so as to avoid dangerous shocks and
consequent liability to breakage of the machinery.
3rd That it can be adjusted so as to move a certain load or overcome a certain
amount of resistance and if by accidental means, such as breakages or obstructions
to any part of the machinery additional resistance be communicated to the clutch
it will slip and so indicate that something is wrong with some part of the
machinery when the driving shaft can be stopped and so prevent further damage
to the machinery
4th That it can be easily and instantaneously thrown out of gear while the
driving shaft is running at full speed.
Reference being had to the accompanying drawings and to the figures and
letters of reference marked thereon; like letters throughout referring to like parts.
Fig. 1 is a side elevation of the driving shaft, driving pulley and clutch.
Fig 2 shews a view of the driving shaft, disc plate and driving wheel on
line 3-4.
Fig. 3 shews a view of the driving shaft, friction wheel and clip or brake on
line 5-6.
Fig. 4 shews a view of the sliding piece on line 7-8.
Fig. 5. shews a sectional view of the driving shaft, driving pulley and clutch on
line 1-2.
Fig. 6 shews an alternative method of fixing the pins in the arms of the driving
wheel instead of the disc plate.
Fig. 7. shews a sectional view on line 9-10.
A is the driving shaft, B the driving wheel or pulley to which motion is required
to be communicated from the driving shaft when the clutch is in gear, but is made

page_text: to run loose on the driving shaft when the clutch is out of gear so that the driving
On the boss C
shaft can rotate if required and the driving wheel remain at rest.
of the driving wheel B is cast or keyed, a disc plate D with four or other number
of pins E. The disc plate D thus fixed to the boss C rotates with the driving
wheel B when the clutch is in gear and remains at rest when the clutch is out of
gear. F is a friction wheel keyed on to and made to rotate with the driving
shaft A. On the friction wheel F is a clip or brake G made in four or other
number of parts, both ends of each part of the clip or brake being made with pro-
jections H through which are holes J chased with screw threads to receive right
and left hand threaded screws K. The projections H are preferably made with
recesses L to receive nuts M chased with screw threads to receive the right and left
hand threaded screws K. Each part of the clip or brake is made with a pin hole N
to receive the pins E on the disc plate D. On the right and left hand threaded
screws K are fixed levers O which are connected with the arms P of the sliding
piece Qby the links R. On the sliding piece Q is a groove S in which a forked or
other form of lever T. works to move the sliding piece on the driving shaft A, but
the lever forms no part of this invention.
Now according to this invention when the sliding piece Q is made to slide on the
driving shaft A by a lever in the usual way, motion is communicated to the right
and left hand threaded screws K by the links R and levers O by which means the
clip or brake G opens and allows the friction wheel F to revolve freely with the
driving shaft A while the driving wheel remains at rest. When the sliding piece Q
is made to slide on the driving shaft A in the opposite direction to that described,
motion is communicated to the right and left hand threaded screws K by the links R
and levers O by which means the clip or brake G closes and grips the friction
wheel F which being keyed on the driving shaft A, causes the clip or brake G to
revolve with the friction wheel F and driving shaft A and communicates motion to
the disc plate D and driving wheel B through the disc plate pins E.
The right and left hand threaded screws K can be so arranged that the clutch
can be put into gear by moving the sliding piece Q either towards or from the
driving wheel B as may be required and put out of gear by moving the sliding
piece in the opposite direction to that required for putting the clutch into gear.
As the sliding piece Q can be slid on the driving shaft A to communicate motion to
the right and left hand threaded screws K either to open or close the clip or brake G
both when the driving shaft is at rest or running at full speed, the clutch can be
effectually put into or out of gear as may be required whether the driving shaft is
at rest or running at full speed.
As the clip or brake G can be gradually closed to grip the friction wheel F by
the gradual motion of the right and left hand threaded screws K motion is
gradually communicated to the driving wheel B until it has attained the required
velocity.
The clip or brake G can be adjusted to grip the friction wheel by the amount
of motion given to the right and left hand threaded screws K. so as to remove a
given load or overcome a certain amount of resistance.
We do not bind ourselves to the exact form of apparatus shewn in the drawings,
as it may be varied in many ways, as for instance the disc plate D and pins E
connected therewith may be dispensed with the friction wheel F keyed to the boss
of the driving wheel B and the sliding piece Q made to rotate with the shaft A by
sliding on a key fast thereto. When the clip or brake G was tightened on the
friction wheel the motion would be conveyed to the driving wheel B through the
arms of the sliding piece Q.
This form of clip or strap brake tightened by means of right and left hand screws
may also be applied to check the impetus of revolving shafts et cetera instead of the
form of strap brake at present in use. The friction wheel would then be made fast
to and would revolve with such shaft and the sliding piece slide on a fixed shaft or
support.
Having now described our invention and the best mode known to us of carrying

page_text: it into effect we wish it to be understood that we do not make a general claim for
the use of friction clutches and brakes for starting or stopping machinery but that
what we believe to be new and desire to protect under the hereinbefore in part
recited Letters Patent is :-
First. The construction of clutches for engaging and disengaging parts of
machinery in which frictional contact is established between one part and another
by means of a clip or strap passing around a frictional wheel or its mechanical
equivalent. joined together at the ends by a screw or equivalent device whereby its
length may be varied by the operation of levers controlled by a handle and slide
substantially as described.
Second. In a frictional clutch or brake the use of clip or strap made of two or
more parts connected together by right or left handed screws operated by sliding
arms substantially as described and shown.
Third. The general construction and arrangement of apparatus for engaging and
disengaging parts of machinery when taken as a whole substantially as described
and shown.
In witness whereof I, the said John Scarisbrick Walker for and on behalf of
myself and the said Henry Fisher have hereunto set my hand and seal this
twenty sixth day of January in the year of our Lord one thousand eight
hundred and eighty three.
JOHN SCARISBRICK WALKER (L.S.)