Tension Device for Belts.
Year: 1890

page_text: Date of Application, 24th Sept., 1890
Complete Specification Left, 24th June, 1891-Accepted, 22nd Aug., 1891
PROVISIONAL SPECIFICATION.
Tension Device for Belts.
I, JOHN PITT BAYLY, of 18 Fulham Place, Paddington, in the County of
London, Patent Agent, do hereby declare the nature of this invention (a com-
munication to me from abroad by Anders Anderson, Inventor, and Joe Hellhoff,
Gentleman, both of West Oakland, California, U.S.A.) to be as follows:-
This invention has reference to a certain new and useful device for regulating the
tension of pulley belts; and which invention has for its object to prevent the slipping
of the belts under great strain.
By this invention a disc is loosely mounted upon the drive shaft at each side of
the pulley, and each disc is provided upon its inner face with an annular groove,
which is located near the periphery of each. A suitable fender is fixedly secured
in said grooves, the discs connecting the same. A second fender is held to slide in
said grooves, over the fixed fender, and is provided with means for limiting the
movement of the sliding fender. A suitable friction pulley is mounted upon a shaft
journalled in the ends of two side levers, the lower ends of which are secured to a
rock shaft journalled in suitable hangers fixed in position beneath the belt, and
which friction pulley is adapted to be brought into contact with the belt with more
or less pressure, by means of a suitable hand lever applied to the rock shaft for that
purpose.
The hand lever is adapted to be retained in position by the ordinary rack and
catch mechanism usually combined with such hand levers.
Dated this 24th day of September 1890.
J. P. BAYLY,
Applicant.
COMPLETE SPECIFICATION.
Tension Device for Belts.
I, JOHN PITT BAYLY, of 18 Fulham Place, Paddington, in the County of
London, Patent Agent, do hereby declare the nature of this invention (a com-
munication to me from abroad by Anders Anderson, Inventor, and Joe Hellhoff,
Gentleman, both of West Oakland, California, U.S.A.) and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
My invention relates to an improvement in tension devices for belts, and has for
its object to provide a device of simple and durable construction, capable of attach-
ment to any driving-pulley, for instance, and which will dispense with the necessity
of loose pulleys.
A further object of the invention is to dispense with the use of the shifter in
contact with the belt, and to so construct the device that the movement of the lever
in one direction will cause the drive-wheel to transfer motion to the driving-belt,
and when the lever is moved in the opposite direction wherein the driving-pulley
may rotate without engaging the belt.
The invention consists in the novel construction and combination of the
several parts, as will be hereinafter fully described, and pointed out in the
claims.
Reference is to be had to the accompanying drawings, forming a part of this
Specification, in which similar figures of reference indicate corresponding parts in
all the views

page_text: Fig. 1 is a side elevation of the improvement applied to the driving-pulley of a
machine.
Fig. 2 is a partial side elevation and, section, the section being taken practically
upon the line of Fig. 4, the device being in position to permit, the pulley to
rotate without engaging with the driving-belt.
Fig. 3 is a view similar to that illustrated in Fig. 2, the device being in position
to cause the driving-belt to be rotated by the driving-pulley.
Fig. 4 is a plan view of the device, and
Fig. 5 is a transverse section taken practically upon lines y y of Figs. 2 and 4:
The ends of the drive-shaft 10 are journalled in any suitable form of bearings 11;
and between the said bearings 11 two pillars 12 are projected vertically upward
from a base-plate 13. Upon the upper end of each pillar a journal-box 14 is
secured or formed integral therewith, the bore of said boxes being preferably of
much greater diameter than the diameter of the drive-shaft. These boxes 14 are
ordinarily located one at each side of the centre of the drive-shaft, and between
the said boxes a drive-pulley 15 is keyed or otherwise attached to the shaft, as
shown in Fig. 5. At each side of the drive-pulley 15 a disc 16 and 17 is respectively
located, loosely mounted upon the drive-shaft, each of the discs being ordinarily
provided with a hub, and the boxes 14 are so located with respect to the discs that
their inner ends virtually contact with the outer ends of the hubs, as is also best
shown in Fig. 5, so as not to come in contact with the drive-shaft. The discs 16
and 17 are tied together by a fender 18, located near the periphery, the side edges
of the said fender being secured in the inner faces of the discs. The fender 18 is
semicircular, and is ordinarily made of a length corresponding to about one-third
of the circumference of the discs. Upon the inner face of each disc a groove 19
is produced, which groove follows the peripheral contour of the disc, and in said
grooves 19 the fender 18 is secured. The grooves 19 of the discs are of greater
width than the fender 18, whereby a second movable fender 20, held to slide in
said grooves, may, when the occasion demands, slide over to a contact with the
outer face of the fixed fender. The movement of the fender 20 is limited in one
direction by contact with stop-pins 21, one of said pins being preferably located in
cach of the grooves 19, and the movement of the said sliding fender 20 is limited
in the other direction by contact with an arm 22, located in front of the drive-pulley
between the discs.
Upon the hub of the disc 17 a pinion 23 is formed, which pinion is provided with
a toothless surface 24, which toothless surface constitutes about one-eighth of the
circumferential surface of the said pinion, as illustrated in Fig. 1.
The driving-belt 25 is illustrated as passed over the drive-pulley 15, and also over
a smaller pulley 26, mounted upon a counter-shaft 27. Near the said counter-
shaft 27 an essentially U-shaped hanger 28 is journalled in brackets or standards 29,
secured to any suitable support, and between the members of said hanger a friction-
pulley 30 is journalled, the said pulley being provided with a peripheral groove to
receive the driving-belt 25. One of the brackets or standards 29 is carried upward
above the other, and the upper surface is formed with a series of teeth. 31 to
constitute a rack, and the hanger is provided with a trunnion, which extends.
through and beyond the bracket or standard constituting the rack, and to the said t
trunnion, the lower end of a lever 32 is secured, which lever is provided with the
usual thumb-latch 33, adapted to engage the toothed surface 31 of the bracket or
standard, as is best shown in Figs. 1 and 2.
At or near the centre of the lever 32, upon its outer face, one extremity of a
rod 34 is pivoted, and upon the under face of the other end of the said rod teeth.
are produced to form a rack 35, which rack is. adapted to contact with the
pinion 23.
In order to prevent the rack from leaving the pinion, an arm 36
is loosely mounted upon the drive-shaft, which arm carries at its upper extremity
a friction-roller 37, which roller engages with the upper surface of the rack 35.
In operation, when it is desired to. stop the revolution of the counter-shaft 27,
the lever 32 is thrown in direction of the drive-pulley, as shown in Figs. 1 and 2,

page_text: whereupon the hanger 28, carrying the friction-pulley 30, is thrown downward to
such an extent as to elongate the belt 25. In throwing the lever 32 in the direction
of the drive-pulley the rod 34 is also pushed in the direction of the said pulley, and
the racked surface 35, acting upon the pinion 23, turns the said pinion and causes
the discs 16 and 17 to make a partial revolution, the result of which is to cause the
loose or movable fender 20 to drop into the grooves 19 of the discs and contact
virtually at one end with the fixed fender 18, as shown in Fig. 2, and at the
opposite end with the stop-pins 21. Thus the two fenders 18 and 20 form a shield
covering the upper or two-thirds' portion of the drive-pulley, and with said fenders
the driving-belt 25 contacts, and is thereby held out of engagement with the drive-
pulley. Thus the movement of the counter-shaft 27 is suddenly stopped and the
belt 25 is idle.
In order to set the counter-shaft 27 in motion, the lever 32 is carried in the
direction of the said counter-shaft, as illustrated in Fig. 3, and the racked surface
of the rod 34 acting upon the pinion causes the discs 16 and 17 to make a partial
revolution in the direction of the said counter-shaft, whereupon the movable
fender 20 is made to slide upon the fixed fender 18 as the latter is carried down-
ward, and when the revolution of the discs has been stopped by the lever 32
reaching its greatest forward pitch the movable fender 20 drops by gravity and
contacts with the stop 22, whereupon both fenders are concentrically situated and
located between the upper and lower members of the drive-belt out of contact
with the latter. The said belt, when the discs and the fenders are in this position,
contacts virtually with the drive-pulley and is moved thereby, the slack in the
belt 25 being taken up by the friction-pulley 30, which acts as an idler, and is
carried upward by the hanger being brought to a vertical position, as is shown in
the said Fig. 3.
It will be observed by reference to the drawings and to the foregoing description
that the necessity of a shifting-fork or of a loose-pulley is dispensed with, and,
further, that motion may be communicated to the counter-shaft from the drive-shaft,
or the revolution of the counter-shaft be stopped by an exceedingly simple and
conveniently-manipulated mechanism, thus saving the wear and tear of two belts,
two sets of shafts and boxes, and the wear of the shifting-fork on the edges of
the belt, and last, but not least, the wear of the loose-pulley, which has always been
bothersome.
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, with the drive-shaft and drive-pulley, of discs arranged at
the side of said pulley connected by a fixed fender and provided with a movable
or gravity fender, a friction-pulley adapted for contact with the belt of the drive-
pulley, a lever secured to the hangers of the friction-pulley, and a rack-and-pinion
connection between the said lever and the discs located near the drive-pulley,
substantially as shown and described.
2. The combination, with a drive-shaft and a pulley fixed thereon, of a disc
loosely mounted upon the drive-shaft at each side of the drive-pulley, a semi-
circular fender uniting the attached to the said discs, a movable semicircular
fender capable of sliding in the discs and upon the fixed fender, a friction pulley
adapted for contact with the belt of the drive-pulley, a lever secured to the
hanger of said pulley, a pinion secured to one of said discs, and a rack attached
to the lever and contacting with said pinion, substantially as and for the purposes
specified.
3. The combination, with a drive-shaft, a drive-pulley mounted thereon, and a
disc loosely mounted upon said drive-shaft each side of said pulley, each disc
being provided upon its inner face with an annular groove located near the
periphery, of a fender fixedly secured in said grooves, the discs connecting the
same, a second fender held to slide in said grooves over the fixed fender, the means

page_text: for limiting the movement of the sliding fender, a friction-pulley adapted to contact
with the belt of the drive-pulley, a lever secured to the hanger of the friction-pulley,
a pinion attached to one of the discs, a rack pivoted at one end to the lever and
contacting at its opposite end with said pinion, and a guide-arm loosely mounted
upon the drive-shaft and engaging with the rack, all combined for operation
substantially as and for the purpose specified.
Dated this 24th day of June 1891.
J. P. BAYLY.
Appl