IMPROVEMENTS IN SAFETY APPARATUS FOR CAGES AND HOISTS
Year: 1865

page_text: LETTERS PATENT to Jubal Charlton Broadbent, of Rochdale, in the
County of Lancaster, Engineer, for the Invention of "IMPROVEMENTS IN
SAFETY APPARATUS FOR CAGES AND HOISTS."
Sealed the 9th March 1866, and dated the 19th September 1865.
PROVISIONAL SPECIFICATION left by the said Jubal Charlton Broadbent
at the Office of the Commissioners of Patents, with his Petition, on the
19th September 1865.
I, JUBAL CHARLTON BROADBENT, of Rochdale, in the County of Lancaster,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN SAFETY APPARATUS FOR CAGES AND HOISTS," to be as follows:-
The object of my Invention is to prevent the descent of the cage-when the
rope or the chains for connecting the cage to the rope break.
In hoists of the ordinary construction the cage is guided by uprights of
wood or wire rope placed at each side of the cage. Now my Invention con-
sists in applying to each side of each upright a weighted eccentric jointed to
studs fixed to the cage and connected by an adjustable link to the chains
which are attached to the rope.
When the cage is ascending or descending, the strain on the connecting
chains holds the eccentrics clear of the upright guides, but on the breakage of
the rope or chains the weighted eccentrics are instantly brought into contact
with and bind against the guides, thus preventing the descent of the cage. The
surfaces of the eccentrics are made serrated to give the requisite friction.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jubal Charlton Broadbent in the Great Seal Patent Office
on the 14th March 1866.
TO-ALL TO WHOM THESE PRESENTS SHALL COME, I, JUBAL
*CHARLTON BROADBENT, of Rochdale, in the County of Lancaster, Engineer,
:send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of September, in the year of our
Lord One thousand eight hundred and sixty-five, in the twenty-ninth year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Jubal Charlton Broadbent, Her special license that I,
the said Jubal Charlton Broadbent, my executors, administrators, and
assigns, or such others as I, the said Jubal Charlton Broadbent, my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain, and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
SAFETY APPARATUS FOR CAGES AND HOISTS," upon the condition (amongst others)
that I, the said Jubal Charlton Broadbent, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause the
same to be filed in the Great Seal Patent Office within six calendar months
next and immediately:after the date of the said Letters Patent..
same
NOW KNOW YE, that I, the said Jubal Chariton Broadbent, do hereby
'declare the nature of my said Invention, and in, what manner the
is to be performed, to be particularly described and ascertained in and by
the following statement (that is to say) :—
1
The object of my Invention is to prevent the descent of the cage of a hoist
when the rope or the chains for connecting the cage to the rope break.
..In hoists of the ordinary construction the cage is guided by uprights placed
at each side of the cage. Now my Invention consists in applying to each
side of each upright a weighted eccentric. jointed to studs fixed to the cage,

page_text: and connected by an adjustable link to the chains, which are attached to
the rope.
:
:
When the cage is ascending or descending the strain on the connecting
chains holds the eccentrics clear of the upright guides, but on the breakage of
the rope or chains the weighted eccentrics are instantly brought into contact
with and bind against the guides, thus preventing the descent of the cage.
The surfaces of the eccentrics are made serrated to give the requisite friction..
I wish to observe that my improvements are equally applicable to cages
that are guided at the four corners.
And in order that my Invention may be fully understood and readily carried.
into effect I will proceed to describe the accompanying Sheet of Drawings,
reference being had to the figures and letters marked thereon.
Figure 1 represents a safety cage suitable for a coal pit, to which my
improvements are applied; this view shows the parts in the positions they
occupy when the cage is going up or down; Figure 2 represents the 'same
safety cage with the parts in the positions they would assume when the rope
breaks.
.
:
a, a, are the sides; b, the bottom; and c the top rail of the cage, which is
constructed in the usual manner; d is the lower end of the wire or other rope
for raising and lowering the cage; the ring d' at the end of the rope d is
connected to the cage by the four diagonal chains e as usual; are the guides
which are supposed to be made of wood, but may be wire ropes if preferred.
At the under side of the top rail c and to the sides a of the cage are secured
the cross bars g, in each of which are fixed two studs h, serving as fulcra for
the weighted eccentrics i, the surfaces of which are serrated to give the requisite
friction or bite when they come in contact with the guides f, and each eccentric
i is connected by a short chainj to the chains c.
The mode of operation is as follows:-So long as the cage continues to
ascend and descend by the usual winding and unwinding gear connected to the
rope d, the weighted eccentrics i are held by the chains j clear of the guides f,
as shown in Figure 1, but the moment the rope d breaks the connecting
chains e drop on the roof or cap of the cage, and the eccentrics i being no
longer held up by the chains j swivel partly round on their fulcrum studs h,
and their serrated surfaces coming in contact with the guides f, as shewn in
Figure 2, instantly take hold of the same, and prevent the further descent of
the cage and hold it securely until the rope d has been repaired. In order to
accelerate the action of the eccentrics i, when the rope breaks each pair of
eccentrics may be connected by a spring k, as shewn by dotted lines in
Figure 1.

page_text: By means of these improvements accidents from the breaking of the rope
are prevented, and the apparatus is so simple that it is impossible to get
deranged; the apparatus can be applied to the cages of coal and other mines,
and to hoists of every description in a very short time and at little expense,
and the weight of the parts is inconsiderable.
Having thus described the nature of my Invention, and the manner of
performing the same, I declare that I claim the improved mode of applying
weighted or self-acting eccentrics to the cages of hoists, as shewn and
described, or any modification of the same.
In witness whereof; I, the said Jubal Charlton Broadbent, have hereunto.
set my hand and scal, the Thirteenth day of March One thousand eight
hundred and sixty-six.
JUBAL C. BROADBENT. (L.S.)