Varying Speed Motion.
Year: 1894

page_text: Date of Application, 30th June, 1894
Complete Specification Left. 27th Se t.. 1594-Accepted, 3rd Nov., 1894
Varying Speed Motion.
I, WILLIAM MARCH of 69 Adelaide Road, South Hampstead in the County of
London, Mechanical Engineer do hereby declare the nature of this invention to be
as follows:-
My invention consists of two truncated cone pullies concaved on their faces,
with the axles parallel to each other, & with the larger end of the one cone opposite
to the smaller end of the other. The cones have a space between them.
Immediately over this space there is a small communicating wheel which rests upon
both cones.
The circumference of this wheel is made of rubber. paper, wood or
other material different to that of the cones; & its axle is parallel with the axles
of the cones.
The axle of this wheel revolves in a pair of blocks which slide to &
fro in a small frame which is made to travel lengthways with the cones in either
direction by means of a long screw which is placed in the middle of the narrow
space between the cones & which passes through the aforesaid frame which is
tapped to fit the screw. When require to transmit much power, there are two of
these small wheels, one of which presses against the upper faces of the cones, &
the other against the lower faces of the same. Both wheels are made to travel
simultaneously in the same direction by means of the aforesaid screw. The
pressure of the wheel or wheels against the face of the cones is effected by set
screws, springs, or weighted levers attached to the travelling frame & bearing upon
the back of the aforesaid sliding blocks.
Dated this 30th day of June 1894.
WILLIAM MARCH.
Varying Speed Motion.
I, WILLIAM MARCH of 69 Adelaide Road, South Hampstead, Engineer, do
hereby declare the nature of this invention and in what manner the same is to he
performed, to be particularly described and ascertained in and by the following
statement:-
This invention refers to contrivances for varying the speed of moving bodies
such as tramway engines and other machines, and is also applicable as an
overhead motion for lathes, and for many other purposes where variable speed is
required.
It consists of two truncated conical pulleys slightly concaved on their surfaces
and with their axles parallel. Their ends are reversed so that the large end of one
cone is opposite to the small end of the other.
The cones are not in contact there being a sinall space between them. Adjoining
this space and in contact with both cones runs a small friction pulley wheel which
conveys power from one to the other. The rim of this wheel is formed of india-
rubber or other elastic substance.
The axle of the intermediate wheel is parallel to the axles of the cones, and
revolves in a pair of blocks connected with a fork which slides to and fro in a
small frame.
This frame is made to travel lengthwise with the cones in either direction by
means of a long screw which is placed in the middle of the narrow space between

page_text: the cones and which passes through the aforesaid frame which is tapped to fit the
screw.
When required to transmit much power there are two of these small friction
wheels, one opposite to the other on alternate sides of the cones. Both wheels are
made to travel simultaneously in the same direction by means of the aforesaid
screw.
The pressure of the small wheel or wheels against the faces of the cones is
effected by a screw or screws, springs or weighted levers attached to the travelling
frame and bearing upon the back of the aforesaid sliding blocks.
I will now describe the invention as applied for the overhead motion of a lathe
and with reference to the accompanying drawings in which,
Fig. 1 shows a plan view of my improved speed cone gear.
Fig. 2 shows a side view and Fig. 3 shows an end view of same.
a, a, are the two truncated cones, made with concave peripheries and placed each
with its large end opposite the small end of the other.
,, are spindles supporting the cones a, a, and mounted in bearings c, c.
d, d, are hand pulleys one mounted on each end of the ends of the spindles b, b.
One of these pulleys receives power from the main driving shaft or otherwise, and
the other gives off or imparts power to the tool being driven. e, is a screwed rod
mounted obliquely between the faces of the cones a, a, and running in bearings c, c.
e, is a chain wheel mounted on the end of the rod e, and is operated from below
when the speed requires adjustment. f, is a movable or adjustable forked bearing
depending from and operated by turning the screwed rod e. This bearing supports
the adjustable friction wheel g. 9, is a small india-rubber faced friction wheel
mounted in the bearing. This wheel when put into contact with the faces of the
cones a, a, considerably increases or decreases the speed of the driven cone in
proportion as its bearing, is moved along the rod e. h, is a forked frame
supporting the bearing.k, is a small screwed spindle passing through the lower
or loop end of the bearing h, and attached firmly to the loop end of the bearing f.
The operator can by turning the screw throw the face of the wheel g, into or out
of contact with the cones a, a. k', is a slot on each side of the bearing, to allow
of this upward and downward movement of the wheel g.
Thus it will be seen that by the above arrangement a loose pulley is dispensed
with as the transmission of power is stopped by withdrawing the friction wheel and
can be re-commenced by pressing it again into contact with the cones.
When used for tramway engines and like purposes the chain wheel is not
required, as the adjustment can be made by a hand wheel or crank.
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. The combination of two identical truncated cone pulleys concaved on their
faces, (mounted on parallel axles and kept slightly apart, the larger end of each
cone being opposite to the smaller end of the other,) with one or more intermediate
friction wheels, faced with rubber or other equally elastic substance, which gear
against both cones and communicate power from one to the other; said intermediate
wheels being mounted on an axle parallel to the axles of the cones and on a
travelling frame, so as to travel to and fro at will, lengthwise with said cones, and
operated by a screw and chain wheel or other device, and said intermediate wheels
being held against said cones by springs, weighted levers or screws, as herein
described and set forth.
Dated this 27th day of September 1891
S. S. BROMHEAD,
97, Newgate Street, E.C., Patent Agent.