Improvements in Mechanism for Transmitting Motion.
Year: 1887

page_text: Date of App ication, 6th Dec., 1887
Specification Accepted, 13th Jan., 1888
COMPLETE SPECIFICATION.
Improvements in Mechanism for Transmitting Motion.
I, GEORGE FRANK EVANS, Machinist, and resident in Somerville, County of
Middlesex and State of Massachusetts, United States of America, 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:-
This invention relates "Improvements in Mechanism for Transmitting Motion and
consists primarily of an endless belt, in combination with two reversely conical or
tapering pulleys mounted upon parallel shafts. Furthermore said endless belt loosely
encircles one pulley and passes between the adjacent surfaces of said pulleys by which
it is firmly gripped, the frictional contact thus produced causes the rotation of one
pulley, the driver, to be directly transmitted to and effects the revolution of the other,
the driven pulley.
The aim of my invention is to effect three essential objects; firstly, in the
mechanism by which the endless belt can be speedily adjusted end wise and its
position between the surfaces of the pulleys controlled; secondly, in the stop motion
provided for such belt by means of the construction and form of the peripheries of
said pulleys, and thirdly and lastly in the instrumentalities, whereby one pulley is
made movable towards or away from the other in a direction at right angles to the
shaft of the fixed or non-adjustable pulley.
The drawings represent in Fig. 1 a perspective view of a device embodying my
improvements. Fig. 2 is a plan of the same; Fig. 3 is an elevation in part showing
its application to a hanger and the means by which adjustment of the belt endwise is
effected. Fig. 5. is a vertical section longitudinally of a hanger representing a modi-
fication in the mechanism for adjusting one pulley toward or away from the other.
In the drawings 2. 3. represent two oppositely disposed conical or tapering pulleys,
suitably mounted, and between which is gripped an endless belt 4, which loosely
girdles one of the pulleys.
Shafts 5. 6 which support the latter are journaled, see Fig. 1, in two housings or
standards 7. 8. securely affixed upon the floor of a building. If desired hangers may
be substituted and the entire device can then be suspended from the ceiling of a room.
My improvements relate firstly to operative mechanism by which the endless belt
can at any time, even when the pulleys are running be shifted end wise, or longitudinally
027

page_text: of said pulleys to change the speed, or in order to stop the driven roll 3, which latter
result will be more fully hereinafter described. To effect adjustment in the position of
the belt 4, I have secured upon the housings 7. 8. two upright posts 30 surmounted
with journal hoxes 9. 10. Mounted in said boxes and extending above the pulleys is
placed a screw-threaded shaft 12 furnished at one end with a grooved pulley 13, or
other equivalent actuating device. The boxes 9.10, before mentioned, are so positioned
upon their respective standards, that the screw-threaded shaft 12, is axially aligned
with the parallel adjacent surfaces of the pulleys.
Upon this shaft 12, is mounted a sleeve-nut 14, which engages with and is moved
by the rotations of the shaft. Said nut is provided laterally of the shaft, upon the
side adjacent to the pulley 3, with an extension, which is apertured to receive and
permit the travel of the endless belt 4, therethrough. Oppositely disposed I have
affixed a short arm 15, which engages a guide-rod 16, also mounted upon the upright
posts 30. Said guide-rod is parallel with the screw-shaft 13, and serves to support
and steady the sleeve-nut, as it travels endwise upon the shaft, in the act of adjusting
the endless belt.
The second feature in my improvements is to effect a stop-motion for the belt
without separating the surfaces of the pulleys. To effect this, I have reduced a portion
of the pulleys; thus, when the belt, by means of the screw-rod and its coöperating
parts, is transferred to said portion, the friction ceases and the driven pulley 3 stops at
once. As shown in the drawings two adjacent ends of the pulleys are cut away, or
reduced in diameter, thereby forming an annular recess 17. An easy bevel exists
between the active surfaces of the pulleys and the inactive or reduced portions in order
to facilitate movement of the endless belt between the pulleys, when the driven one is
to be actively employed.
The third feature of my invention consists in the mechanism by which the driven
pulley 3 is moved transversely of its length in lieu of in direction of its length. To
this end I have adjustably mounted the boxes 19, 19, which support said pulley; said
boxes are slotted at 20, 20, and are removably secured in position by bolts 21, 21. To
actuate said boxes and move them equally, when adjustment of the pulley is effected,
I have disposed two short shafts 22, 22, at right angles to the longitudinal axis of
the pulley and screw-threaded one end, which enters and engages the journal-box.
The opposite ends are furnished with miter-gears 23, 23, meshing with similar gears 24,
fixed upon the rod 25; the latter is supported in bearings in the arms 26, which are
bolted to the housings 7, 8; a hand-wheel, or pulley 27 serves to rotate the rod 25.
In the event of the device being employed upon a hanger, a belt or cord may connect
the pulley 13 with a second one upon the floor (not shown) and thus the position of
the endless belt, by means of the sleeve-nut can readily be controlled, see Fig. 3.
In Fig. 2 the pulley 2. is mounted upon the shaft 5, actuated from some prime
motor, or it may be operated by means of the pulley 28, by a belt.
The pulley 29 upon the shaft 6, is intended by means of a belt to actuate and
transmit the power to any desired point, where it may be employed. Other mechanical
means inay be employed however in conveying power in lieu of the belt.
In place of the mechanical arrangement for adjusting one pulley axially with
respect to the other, to increase or diminish the frictional pressure upon the belt
passing therebetween, as shown in Figs. 1 and 2 a modification may be substituted,
which is represented in Fig. 4. In this instance the hangers or castings 31 31, to
which the shaft-boxes 32, of the axially mounted pulley are secured, is formed with
transverse tapering slots 33, 33. Extending between the lower ends of said hangers,
I have located a shaft 34 and secured thereupon two inclined projections or wedges 35,
which fit the taper of the slots 33; to actuate the shaft endwise I have screw-threaded
one end and mounted thereon a hand-wheel 36. In the drawings the boxes 32 are
centrally pivoted upon movable pins or supports 37, which rest upon the wedges 35;
thus endwise movement of the shaft serves to raise or lower said pins, with them the
boxes, and the pulley is moved axially towards or away from the other which
coöperates with it. In lieu of the above, the shaft may rest in ordinary journal boxes
which can be caused to advance or retreat in a similar manner.

page_text: 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:-
1st. In combination with two oppositely disposed conical pulleys 2. 3, adapted to
grip an endless band 4, which loosely encircles one of said pulleys, the screw-threaded
shaft 12, guide-rod 16, and the sleeve-nut 14 apertured to receive the band and
adapted to travel endwise of the pulleys, whereby the belt may be positioned; sub-
stantially as described.
2nd. In a device for transmitting motion from one conical or tapering pulley to
another by pressure of said pulleys upon a band arranged to pass between them, the
pulleys 2. 3, reduced in diameter at adjacent portions to form the annular recess 17,
combined with an endless band, which loosely encircles one pulley and is adapted to
enter said recess, when motion is not to be transmitted, substantially as herein
specified.
3rd. In combination with the pulley 2, in fixed bearings, the pulley 3, in movable
bearings, and the endless band 4, which passes there between the horizontal slotted
boxes 19, the shafts 22, having screw-threaded ends engaging and moving said journal
boxes, the miter gears 23 on the other ends of said shafts and the shaft 25, carrying
additional miter gears 24, meshing therewith by which the pulley 3 is adjustable in
paths of movement transversely of the axis of support of the pulley 2 to increase or
diminish the grip upon the band, as herein stated.
4th. In combination with the pulley 2 in fixed bearings, the pulley 3 in movable
bearings and the endless band 4, which passes therebetween, the mechanism as
described, composed of the shaft 34 with its inclined projections or wedges 35, adapted
to wipe the supports of said pulley 3 and the actuating hand-wheel 36, whereby
movement of the pulley 3 is effected transversely of the axial support of the
coöperating pulley 2 to increase or diminish the frictional pressun upon the band
substantially as described.
1 1000
GEORGE FRANK EVANS,
Boston, Massachusetts, U.S.A.