AN IMPROVED ARRANGEMENT OF APPARATUS APPLICABLE TO HOISTS FOR PREVENTING ACCIDENTS
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I, JOHN CLAYTON of Bradford in the County of York, Working Engineer do
hereby declare the nature of my Invention for "AN IMPROVED ARRANGEMENT
OF APPARATUS APPLICABLE TO HOISTS FOR PREVENTING ACCIDENTS" to be as
follows:-
The object of my Invention is to arrest and stop the downward movement of
the cage, when such cage is descending quicker than is desirable, either through
derangement of the machinery or breakage of some of the parts.
To carry out my Invention I fix a brake pulley (by preference) on the pinion
shaft of the driving gear, and around this pulley is a brake strap connected to a
weighted lever, one end of which rests upon the point or upper end of a vertical
lever or tumbling bar.
At a convenient distance from the tumbling bar is an upright shaft carrying a
pair of governor balls, which expand and close up by the increased and decreased
speed of such shaft, after the manner of governors connected with a steam engine.
The upright shaft has a continuous motion given to it by strap and bevil gearing
from the pinion shaft; so that any increase in speed of the said shaft occasioned by
the quick descent of the cage will be immediately transmitted to the upright shaft,
causing the governor balls to expand, thereby operating a horizontal lever which
pushes the lower end of the tumbling bar out of contact with the weighted lever,
allowing it to drop, and apply the brake to the pulley, thereby immediately
arresting and stopping the descent of the cage.
On pulling down a cord attached to the weighted brake lever, the said lever can
be lifted up again; permitting the upper end of the vertical lever to catch hold of
and support it as before.
By the application of this arrangement of machinery to hoists, accidents occurring
through the quick and sudden descent of the cage will be avoided.

page_text: I, JOHN CLAYTON, of Bradford, in the County of York, Working Engineer, do
hereby declare the nature of my Invention for "AN IMPROVED ARRANGEMENT
OF APPARATUS APPLICABLE TO HOISTS FOR PREVENTING ACCIDENTS," 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 arrest and stop the downward movement of
the cage, when such cage is descending quicker than is desirable either through
derangement of the machinery or breakage of some of the parts.
.
To carry out my Invention I fix a brake-pulley (by preference) on the pinion
shaft of the driving gear, and around this pulley is a brake strap connected to a
weighted lever, one end of which rests upon the point or upper end of a tumbler
or other device.
At a convenient distance from the tumbling bar is an upright shaft carrying a
pair of governor balls which expand and close up by the increased and decreased
speed of such shaft, after the manner of governors connected with a steam engine.
The upright shaft has a continuous motion given to it by strap and bevil gearing
from the pinion shaft, so that any increase in speed of the said shaft occasioned by
the quick descent of the cage will be immediately transmitted to the upright shaft,
causing the governor balls to expand; thereby operating a horizontal lever which
pushes the lower end of the tumbler out of contact with the weighted lever,
allowing it to drop and apply the brake to the pulley thereby immediately
arresting and stopping the descent of the cage.
On pulling down a cord attached to the weighted brake lever, the said lever can
be lifted up again, permitting the upper end of the tumbler to catch hold of and
support it as before.
In order that this Invention may be better understood I herein give reference to
the accompanying Sheet of Drawings which is front elevation of the apparatus I
employ for carrying out my Invention. A is the cage connected by rope B passing
over grooved pulley C driven by spur wheel D from pinion wheel E all arranged
in the usual manner.
On the pinion shaft F I fasten a brake pulley G around which passes a brake H
connected at one end to a stud I, whilst the other end is connected to a rod J, on
the bell crank lever K which is hinged at L and weighted at M. A shaft N is
employed receiving its rotary motion from pinion wheel shaft F by pulleys and
strap P, the said shaft N carrying a bevil wheel R for driving bevil wheel S on the
bottom of vertical shaft T which shaft is provided with a pair of governor balls U
for purposes hereinafter explained. V is a tumbler cast on the back of a circular
plate, the upper end or point a of said tumbler bearing underneath the point b of
the bell crank lever K, so as to keep the pressure of the brake off the pulley whilst
the lower point c of said tumbler is in contact with one end d of the horizontal
lever W, the other end of said lever being in connection with the governor
shaft T.
It will be perceived and at once understood that so long as the cage A is
descending at a proper and recognized speed, that the brake H will be clear of the
pulley G but should any of the machinery break or become deranged so as to admit
of the rapid descent of the carriage that such increased speed would be communi-
cated from the pinion shaft F to the shaft N whereby the speed of the shaft T
would be increased causing the governors thereon to expand and the boss X to rise
carrying with it one end of the horizontal lever W causing the other end thereof to

page_text: lower by which means the bottom of the tumbler is thrown forward bringing its
upper end backward, consequently removing it from under the bell crank lever K,
which after being set at liberty is drawn downward by the weight M whereby the
brake is applied, and almost immediately stops any further descent of the cage
consequently accidents which might happen are avoided.
The pressure of the brake is removed, and the tumbler brought back to its
position again by pulling down the rope Z which by preference is long enough to
reach the bottom of the hoist. As soon as the point 6 of the bell crank lever is
lifted high enough to clear the tumbler the weight e on the circular plate causes
the tumbler to assume it normal position again, and supporting the bell crank
lever.
By the application of this arrangement of machinery to hoists, accidents occurring
through the quick and sudden descent of the cage will be avoided.
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,
Firstly. The employment in a hoist, of the bell crank lever K used for the purpose
of applying a brake when set at liberty, in manner substantially as herein shewn
and described.
Secondly. The employment in a hoist, of the tumbler V or its equivalent,
substantially as herein shewn and described.
Thirdly. The employment in a hoist, of governor balls caused to expand by the
rapid descent of the cage, such expansion arresting the descent of said cage, in
manner substantially as herein shewn and described.
Dated this 20th day of September 1884. .