NEW OR IMPROVED APPARATUS FOR MOVING A STRAP OFF AND ON TO A DRIVING PULLEY AND FOR HOLDING THE STRAP WHEN OFF
Year: 1884

page_text: I BENJAMIN ALFRED DOBSON, of the Firm of Dobson and Barlow, of Kay
Street Works Bolton in the County of Lancaster, Machine Maker, do hereby
declare the nature of said Invention for NEW OR IMPROVED APPARATUS FOR
MOVING A STRAP OFF AND ON TO A DRIVING PULLEY AND FOR HOLDING THE
STRAP WHEN OFF,' to be as follows:-
The object of my Invention is to provide apparatus for throwing a driving strap
off a driving pulley on the main or other shaft and putting it on again quickly and
easily for holding the strap when off the pulley.
At one side of the driving pulley I fix a block or rim part of which is concentric
with and in close proximity to the leading side of the driving pulley and I may or
may not fit antifriction rollers on the surface of this block: or I use several rollers
instead of the block and I employ a strap fork fixed to a horizontal sliding bar on
which is a rack into this rack gears a pinion connected to a pulley over which a
rope or band passes, this rope passes over a guide pulley or pulleys to any place
convenient to the operative or workman.
When the rope or band is pulled in one direction the strap is moved by the fork
or guide on to the block or on to the antifriction rollers fitted on the block or rim
or otherwise mounted near the side of the driving pulley and when the rope is
pulled in the other direction, the strap is moved on to the pulley. The surface of
the block or rim or antifriction rollers coincides with and is near to the leading
side of the driving pulley for about one quarter or more or less of its periphery
and is then curved inward toward the centre to allow the strap to hang loose. I
employ antifriction rollers fitted on the surface of the block or rim to lessen the
friction while the strap is being moved from the pulley to the block or vice versa.
When I use antifriction rollers without the block or rin the surfaces of several of
them are in line with the periphery of the driving pulley.
I also employ a shaft or shafts with suitable gears instead of the rope and
pulleys to impart motion to the pinion that actuates the guide bar or I dispense
with the pinion and rack and connect to the guide bar the vertical (upper) arm of
an inverted T lever which is pivoted at the junction of the vertical and horizontal

page_text: arms and I connect a cord or chain or rod to each horizontal arm by which the
guide bar may be moved in either direction. Or I use a bell crank lever with
suitable connecting rods or a vertical rod with a horizontal bar at one end connected
to the guide bar and a lever or handle at the other end. Or I use a straight lever
connected to the guide bar and pivoted either above or below the guide bar.
Or I may dispense with levers and rods and use ropes, straps or chains passing
over pulleys to give the motion in the two directions.
I sometimes make the outer side of the strap fork with a finger to support the
strap when loose and this finger is inclined so as to present the under side of the
strap to the surface of the pulley.

page_text: I BENJAMIN ALFRED DOBSON, of the firm of Dobson and Barlow, of Kay
Street Works, Bolton, in the County of Lancaster, Machine Maker, do hereby
declare the nature of said Invention for NEW OR IMPROVED APPARATUS FOR
MOVING A STRAP OFF AND ON TO A DRIVING PULLEY AND FOR HOLDING
THE
STRAP WHEN OFF, 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 apparatus for throwing a driving strap
off a driving pulley on the main or other shaft and putting it on again quickly
and easily and for holding the strap when off the pulley.
And in order that my Invention may be fully understood and readily carried
into effect I will proceed to describe the accompanying two Sheets of Drawings,
reference being had to the figures and letters marked thereon.
Figure 1 is a view in perspective of my improved apparatus applied to the
driving strap of a mule. Fig. 2 is a view in perspective, on an enlarged scale, of
part of the same.
At one side of the driving pulley a I fix a block or rim b, part of which is
concentric with and in close proximity to the leading side of the driving pulley a
and I may or may not fit antifriction rollers on the surface of this block or as
shown in Figs. 3 and 4, I use several antifriction rollers c instead of the block b and
I employ a strap fork d fixed to a horizontal sliding bar e on which is a rack e¹:
into this rack gears a pinion f connected to a pulley fl over which a rope g or a
band passes; this rope g passes over a guide pulley h to the pulley h¹ or to any
place convenient to the operative or workman.
When the rope or band g is pulled in one direction, the pulley f¹ is turned and
the pinion f moves the sliding bar e and the fork or guide d and so the driving.
strap i is moved on to the block b (or on to the antifriction rollers fitted thereon)
or on to the antifriction rollers c mounted near the side of the driving pulley a
where it remains stationary until the rope g is pulled in the other direction when
the motion of the sliding bar e is reversed and the driving strap i is once more
moved on to the pulley a. The surface of the block or rim b or antifriction
rollers c coincides with and is near to the leading side of the driving pulley a for
about one quarter or more or less of its periphery and is then curved inward toward
the centre to allow the strap i to hang loose.
I sometimes make the outer side of the strap fork with a finger d² (see Fig 2) to
support the strap when loose and this finger d is inclined so as to present the
under side of the strap to the surface of the pulley.
The antifriction rollers (not shown in the Drawings but which I sometimes
employ) are fitted on the surface of the block or rim b in order to lessen the
friction while the strap i is being moved from the pulley a to the block b or vice
versa. When I use antifriction rollers c without the block or rim b as shown in
Figs. 3 and 4, the surfaces of several of them are in line with the periphery of the
driving pulley a.
Figs. 5 to 11 illustrate several alternative arrangements or devices which I
employ in order to move the bar e and strap fork d.
In Figs. 5 and 6 I employ a shaft j on one end of which is fixed a bevel wheel ¹
gearing into a bevel wheel f' connected to the pinion f and at the other end of the
shaft is fixed another bevel wheel which gears into a bevel wheel k¹ fixed on
one end of a shaft k at the other end of which is fixed a handwheel by turning
which the operative may, through the shafts and gears impart motion to the

page_text: pinion and so actuate the bar e and strap fork & and move the driving strap i on
to or off the driving pulley a in the manner already described.
In the arrangement illustrated by Fig. 7, I dispense with the pinion f and rack e¹
and connect to the guide bar e the slotted (upper) arm of an inverted T lever l
which is pivoted at the junction of the vertical and horizontal arms to a stationary
bracket m and I connect a cord n (or chains or rods may be employed) to each
horizontal arm of the lever by which the guide bar e and strap fork & may be
moved in either direction.
In the arrangement shown in Fig. 8 I use a bell-crank lever o pivoted at o¹ to
the stationary bracket m; one end of the bell-crank lever o is slotted and connected
to the guide bar e and at the other end a rod p is pivoted by moving which the
workman is able to move the guide bar e in either direction or if more convenient
instead of the bell-crank lever o I may employ a vertical rod with a horizontal bar
at one end connected to the guide bar e and a lever or handle at the other end for
the workman.
In the arrangement shown in Fig. 9 I use a straight lever q connected to the
guide bar e and pivoted at q¹ to a fixture above the guide bar: it is obvious that
the lever q might be pivoted below the guide bar e, if more convenient.
Fig. 10 illustrates a modification of the arrangement shown in Fig. 9 in which
I connect a rod r to the end of the straight lever q; this rod r is provided with a
handle by means of which it may be moved to and fro in the stationary bearing 2
and so alter the position of the strap fork d.
In the arrangement illustrated by Fig. 11, I dispense with levers and rods and
use the ropes, straps or chains s passing over guiding pulleys t so that by turning
the handwheel u the workman is able to move the guide bar e in the two
directions.
By the use of my Invention the driving straps remain stationary when off the
driving pulleys and therefore cease to communicate motion to the loose pulleys
consequently the latter require less lubrication than usual, the driving straps are
less liable to become saturated with oil and therefore last longer and are maintained
in better condition.
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
I claim is
1.—The combination of a driving pulley with the block or rim b or the anti-
friction rollers c or any equivalent for supporting a driving strap and holding it
stationary when off the driving pulley, substantially as herein set forth for the
purposes specified.
2. The construction, combination and arrangement of parts forming my improved
apparatus for moving a strap off and on to a driving pulley and for holding the
strap when off, substantially in the manner and for the purposes herein described
and as illustrated by the accompanying Drawings,
Dated this 24th day of January 1885