Safety Attachments.
Year: 1893

page_text: Date of Application, 7th Oct.. 1893
Complete Specification Left, 6th Mar., 1894-Accepted, 7th Apr., 1894
PROVISIONAL SPECIFICATION.
Elevator Safety Attachments.
I, CHARLES BAGOT LABATT, of 916 Bush Street, in the City and County of
San Francisco, State of California, U.S.A. Attorney-at-Law, do hereby declare
the nature of this invention to be as follows:-
This invention relates to a safety attachment for elevators.
It consists in certain details of construction which will be more fully explained
hereafter, and has for object to provide a safety attachment for elevators, which
remains out of action as long as the rope by which the elevator is suspended
remains intact, but which will be thrown into action immediately upon the breakage
of the rope, and thereby project a series of safety stops into the line of travel of the
elevator so as to catch and hold the cage.
The guide timbers are arranged upon each side of the shaft or well in which the
elevator travels, and the rope from which the cage is suspended and by which it is
raised and lowered passes over a pulley which is mounted upon a cross shaft. This
cross shaft extends across the full width of the elevator well and its ends are
journaled in boxes which are loosely supported in standards or frames.
The shaft also has other bearing boxes close to the wheel so that it is properly
supported near the point where the strain is brought upon it and it will not spring.
The outer ends of the shaft may be turned down and made considerably lighter as
no special strain is brought upon them.
The intermediate boxes rest upon suitable supports, and both these boxes and
the outer boxes rest upon their supports without any fastening, being retained in
place by the shape of their supports which are made concave or Y-shaped, forming
rests in which the boxes fit snugly and by which they are prevented from any side
motion as long as the apparatus remains intact.
To any point or points of the cross shaft or to sleeves which loosely surround
the shaft, are ropes attached which pass over pulleys upon a second shaft which is
permanently fixed at some distance above the shaft.
Upon the opposite ends of these ropes where they depend after passing over the
pulleys, are fixed the weights. These weights are so adjusted that while the
elevator cage remains suspended by its rope, the weight of the cage is sufficient to
retain the bearing boxes in their supports, but if the rope breaks so as to relieve
the shaft of the weight of the cage, the weights will immediately lift the shaft with
its boxes, upward, the weights descending.
As these weights descend they act immediately upon the stops which are properly
supported either in the guides or in any suitable timbers or frame-work around the
elevator well and in close proximity with the line of travel of the cage, so that when
these stops fall outward from the chamber in which they are normally concealed,
they project into the path of the cage and instantly arrest it, preventing its falling
a distance of more than a few feet. The stops are constructed so that when they
are in their normal position they lie within the chamber to which they are fitted
and do not project into the line of travel of the cage.
These stops are connected with the rope by means of levers which are suitably
fulcrumed with relation to each of the stops, and so connected with the rope that
when the rope is moved by the action of its weight it will tilt the lever and throw
the stop outward. The stop is so balanced that the moment the angle projects a
little beyond the chamber its center of gravity is thrown outward, and the stop will

page_text: fall by its own weight into the line of travel of the elevator cage, and will
immediately arrest the latter.
Dated this Seventh day of October 1893.
Elevator Safety Attachments.
I, CHARLES BAGOT LABATT, of 916 Bush Street in the City and County of
San Francisco, State of California, United States of America, Attorney-at-Law,
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 :-
My invention relates to a safety attachment for elevators, and consists in certain
details of construction which will be more fully explained by reference to the
accompanying drawings upon which :-
Figure 1 is a front view illustrating my device.
Figure 2 is an end view of the same.
Figure 3 is an end view showing a modification.
Figure 4 is an enlarged view of one of the catches.
The object of my invention is to provide a safety attachment for elevators which
remains out of action as long as the rope by which the elevator is suspended remains
intact, but which will be thrown into action immediately upon the breakage of the
rope and thereby project a series of safety stops into the line of travel of the elevator
so as to catch and hold the cage.
AA are the guide timbers arranged upon each side of the shaft or well in which
the elevator B travels.
C is the rope from which the cage is suspended and by which it is raised and
lowered.
This rope passes over a pulley D which is mounted upon a cross-shaft E. This
cross-shaft extends across the full width of the elevator well and its ends are
journaled in boxes F which are loosely supported in standards or frames G. The
shaft also has other bearing boxes H close to the wheel D, so that it is properly
supported near the point where the strain is brought upon it and it will not spring.
The outer ends of the cross shaft E may be turned down and made considerably
lighter as no special strain is brought upon them. The intermediate boxes H rest
upon suitable supports I, and both these boxes H and the outer boxes F rest upon
their supports without any fastening, being retained in place by the shape of their
supports which are, as shewn in the end view (Fig. 2), made concave or V-shaped,
forming rests in which the boxes fit snugly, and by which they are prevented from
any side motion as long as the apparatus remains intact.
To any point or points of the cross-shaft E or to sleeves which loosely surround
the cross-shaft, are attached ropes J which pass over pulleys K upon a second
shaft L, which is permanently fixed at some distance above the cross-shaft E.
Upon the opposite ends of the ropes J where they depend after passing over the
pulleys K are fixed the weights M. These weights are so adjusted that while the
elevator cage B remains suspended by its rope C, the weight of the cage is
sufficient to retain the bearing boxes F and H in their supports, but if the rope C
breaks so as to relieve the shaft E of the weight of the cage the weights M will
immediately lift the shaft E with its boxes upward the weights descending. As the
weights M descend they act immediately upon the stops N which are properly
supported either in the guides A or in any suitable timbers or framework around
the elevator well and in close proximity with the line of travel of the cage, so that

page_text: when these stops N fall outward from the chamber in which they are normally
concealed, they project into the path of the cage and instantly arrest it, preventing
its falling a distance of more than a few feet. The stops N are constructed, as
plainly shewn in Figure 4, so that when they are in their normal position they lie
within the chamber to which they are fitted and do not project into the line of
travel of the cage.
The stops N are connected with the rope J by means of levers which are
suitably fulcrumed with relation to each of the stops, and so connected with the
rope J that when the latter is moved by the action of its weight M it will tilt the
lever O and throw the stop N outward. The stop is so balanced that the moment
the angle projects a little beyond the chamber its centre of gravity is thrown
outward, and the stop N will fall by its own weight into the line of travel of the
elevator cage B, and will immediately arrest the latter.
In Figure 3 I have shewn the rope J extending down below the shaft E, and
the levers which operate the stops N are connected with this portion of the
rope.
In Figure 2 have shewn the levers O connected with that portion of the rope
between the pulley K and the weight M, the operation being essentially the same
in either case.
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. An elevator safety attachment consisting of movable stops N held normally
out of the line of travel of the elevator cage, an elevator cage B moving in a vertical
well, a cross-shaft E loosely mounted in bearings F to move upward, a pulley D
fixed to said cross-shaft, a suspending and hoisting rope C secured to the cage
and supported by the pulley D, ropes J connected to cross-shaft E and passing over
pulleys K above it, and having weights M upon their depending ends, the ropes J
being connected with the stops N so as to throw them outward in the line of travel
of the elevator when the ropes J are moved by the weights M, substantially as
herein described and shewn upon accompanying drawings.
2. An elevator cage B moving in a vertical well, a suspending and hoisting
rope C passing over a pulley D above the line of travel of the cage B the journal
boxes F of which rest loosely in open topped supports and are normally retained
therein by the weight of the elevator or cage, ropes J connected with cross-shaft E
passing over pulleys K above it, and having weights M upon their outer depending
ends, which weights are less than that of the elevator cage B, gravity stops N
contained in chambers situated along the line of travel of the elevator cage, lever
arms connecting the ropes J of the suspended weights M with the stops N,
whereby a breakage of the cage suspending rope C allows the supplemental weights
to move the ropes to which they are attached and throw the stops N outward into
the line of travel of the cage, substantially as herein described.
Dated this Sixth day of March 1894.