Improvements in Pulleys.
Year: 1894

page_text: Date of Application, 2nd Jan., 1894-Accepted, 3rd Feb., 1894
COMPLETE SPECIFICATION.
Communicated from abroad by EDWARD Fox GORDON, of Concord, in the
County of Merrimack and State of New Hampshire, United States of
America, Machinist.]
Improvements in Pulleys.
1, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45 Southampton Buildings, in the County of Middlesex, 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 :-
The object of my invention is to provide driving-pulleys of increased transmitting
power and having a capacity for varying the speed of the driven pulley at the will
of the operator without stopping its rotation; and also to combine with these
variable-speed pulleys an enclosed loose pulley upon which the belt may rest
dormant when desired.
My apparatus is especially adapted to the use of round belts or ropes, and narrow,
thick belts of leather.
My invention consists in a grooved pulley made of two laterally-separable flaring
discs adapted to rotate continuously with their shaft, and provided with hand
wheels having threaded hubs surrounding said shaft for moving one part toward
and from the other.
It also consists in a two-part driving pulley having oblique and sharply inclined
driving surfaces, an interposed spring tending to separate the parts, and means
mounted on the shaft, independent of the pulley, to press said parts toward each
other, in combination with a loose pulley inclosed between the parts of the driving
pulley, and adapted to support the belt in a dormant state when desired.
My invention also includes the said two-part pulley and inclosed loose pulley in
combination with an internal sleeve rotating with the shaft and furnished with
projections entering recesses in the laterally-movable part, whereby said part is
positively driven although having a limited movement lengthwise of the shaft.
The driven pulley may have these laterally-movable parts to adjust it to the width
of the belt used, or be made solid with grooved periphery, and furnished with
a device for taking up the slack of the belt.
In the accompanying drawings,
Figure 1 is a vertical section of one of my improved pulleys with the connected
parts.
Figure 2 is a vertical section in the plane of the driving shaft, showing a suitable
construction for the companion-pulley.
A represents the driving shaft mounted in suitable bearings.
B and C are the two laterally separable parts of my improved pulley, the part B
being fixed in position on its shaft, and the part C having a limited sliding
movement thereon, controlled by suitable means enabling the operator at will, to
move the part. C toward or from the part B while both are in rotation. The
working faces bc of these parts of the pulley are oblique and sharply inclined
toward each other; and those inclined faces bear against the edges or opposite
sides of the belt D, its speed varying according to their distance from each other;
and they increase the speed of the belt as their approach toward each other forces
the belt farther away from the axis of the shaft A, thereby varying the working-
radius of the pulley. The belt will either be round, or flat and thick with edges
slightly inclined, to fit the oblique, converging faces b c.
Between the parts B and C which constantly revolve with their shaft, 1 inter-
pose a loose pulley E, supported by the shaft, but at no time positively driven. It

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has a flat peripheral face e upon which the belt D rests when the parts B C are
sufficiently far asunder to permit it. In such cases the belt is dormant on such
loose pulley, although the two-part pulley BC is in rapid rotation at each side
thereof. When the belt is to be actuated and to impart motion to the driven
pulley F, and to machines connected thereto by the counter-shaft G, the part C is
pressed toward the part B until they grip the belt D between them, lift it from the
idle pulley, and set it in motion. The parts B and C are offset abruptly outward
at the foot of their inclined faces bc, to give interior space for the rim e of the
loose pulley E. These parts have also broad seats or lateral hubs at their centres
for strength and stiffness.
H H are two hand wheels mounted on the shaft A adjacent to the hub of the
sliding part C of my improved pulley. They turn freely upon the shaft and
normally revolve with it, and have internally and externally threaded hubs engaging
each other. A collar fixed on the shaft beside the wheel H' prevents longitudinal
movement beyond the desired point. Now when these wheels are turned in opposite
directions they speedily slide the part C of the pulley in the desired direction and
hold it there. By turning either wheel while the other is held from rotation the
sliding movement is effected more slowly. I prefer to employ the internal. sleeve J,
shown in Figure 1, fitting closely between and rotating with the shaft A and fixed
part B of the two-part pulley, and forming a bushing or enlargement of the shaft
within the loose pulley E. This sleeve has a radial flange J adjacent to the hub
of the loose pulley which it keeps from moving longitudinally on the shaft. The
flange has two or more projecting studs K, entering corresponding holes in the
sliding part C of the pulley, this construction allowing said part to move toward
and from its fellow B without independent rotation. A recess in one end of this
sleeve receives a spring I, which tends to press the sliding part C away from the
part B, when permitted by the hand wheels H H¹.
A grooved solid pulley may be used on the counter-shaft G with suitable means
for taking up the slack of the belt. I however prefer the construction, shown
in Figure 2 where the pulley is in two parts, the fixed disc B having projecting
rigid studs M, and the yielding disc C sliding thereon. A spring N keeps disc (
pressed elastically against the edge of the belt D in any of the positions the
belt may take when the operator varies the distance of the discs of the driving
pulley.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. A variable-speed pulley formed of two laterally-separable discs having
oblique and sharply inclined bearing surfaces adapted to receive at various depths
between them the transmitting belt, in combination with suitable means for varying
the distance of one of said discs from the other, so as, at the will of the operator,
to vary, positively and at defined distances, the working radius of said pulley,
substantially as set forth.
2. A driving pulley formed of two laterally-separable rotating parts with
driving faces sharply inclined toward each other, in combination with hand wheels
loose on the driving shaft and having threaded hubs, whereby the distance between
said parts of the pulley and their grip on the belt, may be varied, substantially as
and for the purpose set forth.
3. A driving pulley formed in two laterally-separable rotary parts having
oblique and sharply inclined driving surfaces, and an inclosed spring tending to
separate them in combination with a loose pulley inclosed between said rotary
parts and having a belt-supporting periphery within and at the foot of said
inclined surfaces, and with means mounted on the shaft, independent of the pulley,
adapted to press its parts toward each other, substantially as and for the purpose
set forth.
4. A two-part driving-pulley with inclined driving surfaces and an inclosed loose

page_text: pulley with its periphery adjacent to such surfaces, in combination with an internal
sleeve rotating with the shaft, formed with a flange controlling the loose pulley aul
having projections entering recesses in the laterally-movable part of the driving
pulley, substantially as and for the purpose set forth.
5. The driving pulley described having laterally-separable parts B C, with
inclined driving surface bc, and the inclosed loose pulley E with its periphery e
beneath such inclined surfaces, in combination with the internal sleeve J around
which said loose pulley revolves the spring L within said sleeve acting to press the
part C of the pulley away from the part B, and with the threaded parts H H'
adapted to press said parts toward each other substantially as and for the purpose
set forth.
Dated this 2nd day of January 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.