Improvements in and connected with Friction Gearing.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Friction Gearing.
I, JOIN CHARLES HOWELL, of 24, Queen Victoria Street, in the City of London,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
For the purpose of equalizing or balancing the strains on the journals of friction
gear, it has heretofore been proposed to have the driving and driven wheel
brought into contact and held together by a third wheel movable in or with its
frame. With this construction it has also generally been proposed to use a
surrounding band or belt travelling over the two outer wheels and tending to take
some of the strain.
According to the present invention it is proposed that the gear shall consist of
four wheels instead of three as in the old system and for the purpose of describing
the nature of the invention it will be assumed that the first wheel is the driven
wheel, the second the driving wheel, while the third and fourth are stress
balancing or pressure wheels, although in reality any of the wheels may be made
to act as either driving, driven, or balancing wheels.
With the construction indicated the driving wheel is mounted in a frame which
latter is capable of slight play and the normal tendency is for the driving and
driven wheels to be out of contact, although for the purpose of this description it
may be assumed that their axles are parallel and in the same horizontal plane.
On the periphery of the driving wheel upon the far side from the driven wheel
are the points of contact with the balancing or pressure wheels one being above
and one below the horizontal plane through the axis.
The balancing or pressure wheels are carried in movable frames worked in
unison so that they may be made to approach or recede from the driving wheel.
They also preferably have a slight play in their bearings in order that when
pressed against the driving wheel they may be forced slightly outwards with
relation to the driven wheel thus tightening to the maximum the belt travelling
around them and the driven wheel.
Various methods of causing the balancing or pressure wheels to work in unison
may be devised, one method is by mounting such wheels in frames meeting at a
common centre on the axle of the driven wheel, the outer ends of such frames
being operated in reverse directions by means of a lever and connecting rods, or
a right and left hand screw operating on the two frames may be employed, or the
axles of the wheels may be fitted to move in a segmental arm so curved as to
cause a decrease in the tension on the belt, and pressure on the driving wheel
as the wheels are opened out, or a double crank axle could be used so that a partial
turn would have the desired result. Whatever the device employed it may carry
electrical contacts and switching devices for reversing the direction of rotation
of the driving wheel when the latter is in the form of an electrical motor.
Dated this 13th day of February 1899.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London,
Chartered Patent Agent, for the Applicant,

page_text: Improvements in and connected with Friction Gearing.
I, JOHN CHARLES HOWELL, of 24, Queen Victoria Street, in the City of London,
Electrical 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:-
-
For the purpose of equalizing or balancing the strains on the journals of friction
gear, it has heretofore been proposed to have the driving and driven wheel
brought into contact and held together by a third wheel movable in or with its
frame. With this construction it has also generally been proposed to use a
surrounding band or belt travelling over the two outer wheels and tending to take
some of the strain.
It has also been proposed that the gear shall consist of four wheels instead of
three such wheels being normally in contact and the adjustment being effected
from the centre wheel. According to my invention I employ a set of three
wheels whose peripheries are normally out of contact but can be brought in
contact with the periphery of a wheel located in a central position between them.
The angular forces in these arrangements acting on the points of contact of the
three outer wheels with the inner wheel tend to relieve the inner wheel journals
from all stress and to counteract the opposing stresses set up on the journals of
the outer wheels. The three wheels are surrounded with a flexible band or the
like whose length is adjusted so that when the wheels are in gear the belt will be
at or near its working tension and the adjustment is effected from the axis of the
outer wheel all as hereinafter described.
One apparatus by which I attain this object is shewn in the accompanying draw-
ing which is an elevation of such apparatus.
In the drawing A represents the central wheel mounted on a spindle say of an
electric or other motor B. The motor in this arrangement is capable of a slight
movement on a pivoting point B', such small movement of oscillation being
arranged to normally remove the pulley A from the wheel C when the gear is at
rest. When the form of pivoting shewn is used the motor may be kept from
lateral movement by bolts B2 which are arranged to allow of the vertical play.
D and E are wheels the axles of which are fixed in bearings which are free to
slide in the slots F F in the levers GH such levers forming an adjustable angular
frame which is pivoted upon the shaft P of the opposite outer wheel C. The wo
levers G and H can be made to approach or recede from each other by the move-
ments of the pivoted lever I acting by means of the connecting rods LL which
are pivoted to it and to the levers G H at the points M M. A flexible band N
is arranged as shewn about the three outer wheels C, D and E, the length of this
band being such that when the outer wheels are in contact with the central
wheel A its tension is at or near its maximum working strain. A lever or other
device can be attached to the axle of the lever I which when turned in one
direction will tend to increase the angle between the levers G and H separating
the wheels DE and so permitting the central wheel to fall away from contact
with the wheel C while a movement in the other direction will decrease the angle
between the levers thus bringing the wheels 1 and E into contact with the central
wheel A and forcing it into contact with the wheel C. Therefore in the present
case as wheel A is made the driver, wheel C will be driven, or if wheel C be
driver then wheel A will be driven. It is of course obvious that either wheel D
or E could be made the driver if necessary. In the case shewn the power would
be taken from off the shaft P of wheel C.
Several other methods can be used for bringing the wheels D and E into contact

page_text: with the wheel A and forcing it against the wheel C, and various other mechanical
devices can also be utilized for causing the angular adjustment levers to be
closed or opened, as my invention is not limited to the particular arrangement
of parts employed for this purpose which I have described and illustrated.
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
1 claim is:
1. In friction gearing an inner and an outer wheel means for mounting one
of same so that it is normally separated from the other friction wheels outside
the inner wheel adapted to bear on said wheel and to bring it and the first outer
wheel together, means for carrying said friction wheels and altering their position
with respect to each other, and a flexible band surrounding the adjustable friction
wheels and the outer wheel so as to counteract the pressure in the opposite
direction on said wheels substantially as described.
2. In friction gearing an inner and an outer wheel so mounted as to be normally
separated, friction wheels outside the inner wheel adapted to bear on said wheel
and to bring it and the first outer wheel. together, levers carrying said friction
wheels, means for allowing such wheels play in the levers, said levers having
their pivot points on the axis of the first outer wheel and means for moving the
levers and friction wheels together and apart, and a band surrounding the friction
wheels and the first outer wheel so as to counteract the pressure in the opposite
direction on said wheels substantially as described.
Dated this 4th day of November 1899.
PHILIP M. JUSTICE,
65 & 56, Chancery Lane, London,
Chartered Patent Agent, for the Applicant.