IMPROVEMENTS IN HOISTS WHEREIN GUIDED CAGES OR PLATFORMS ARE EMPLOYED, AND APPARATUS CONNECTED THEREWITH
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by John Vivian and Joseph Black-
burn at the Office of the Commissioners of Patents, with their
Petition, on the 10th March 1875.
We, JOHN VIVIAN, of Whitehaven, in the County of Cumberland, Civil
Engineer, and JOSEPH BLACKBURN, Engine Driver, of Rowra, in the
Parish of Arlecdon, in the County of Cumberland, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN HOISTS WHEREIN GUIDED
CAGES OR PLATFORMS ARE EMPLOYED, AND APPARATUS CONNECTED THEREWITH," to
be as follows:-
The first part of our Invention relates to a mode of opening the
"keeps,"
," "caps," or guards on which cages rest by self-acting arrange-
ments, so that it is not necessary for a man to be stationed at the pit top
to open the "
caps," but the engine driver is able when hoisting to drop
the cage on to the caps or to open them, so that the cage can descend
into the pit. This can be done in several ways, the acting principle of
them all however being that when the cage is raised a given height
above the caps (considerably higher than is required to clear them) the
said caps are thrown temporarily out of gear to allow the cage to decend
unimpeded.

page_text: The plan we prefer is as follows:-The cross bars working the caps
are made with links or slots, into or between which wedge-shaped
weights are made to fall, and in falling open the caps, so that the cage
is free to decend the pit. When the cage is hoisted it lifts and suspends
with catches these weights from the links, and the caps fall in for the
cage to rest upon them. The slides in which the weights work are
slightly inclined, being further from the cage in their upper than their
lower portion. When therefore the engine driver wishes to cause the
cage to descend the pit he raises it up till the catches can no longer
grasp the weights, when the latter fall, and in falling open the caps.
The catches are jointed to fold upwards, so that the cage will descend
without the catches acting on the weights.
We propose to cushion the fall of the weights by causing them to
compress air in cylinders at the bottom, or by india-rubber disks or
springs.
The weights can be made if desirable to act directly on the lovers
that work the caps.
Another plan on the same principle, but doing without a sliding
weight altogether, is as follows:-The caps are weighted or arranged to
stand in equilibrio in only two positions, one in gear, the other out;
they are generally in gear so as to catch a cage decending upon them.
Two levers, one below the cage and one considerably above, jut out into
the shaft, the one above only when the caps are in gear, the one below
only when they are out of gear. By moving either of these levers the
position of the caps is changed. When therefore the engine driver :
wishes to descend he raises the cage, till coming in contact with the
upper lever the latter is moved aside, and in moving reverses the caps.
The cage now descends, and when beyond the caps meets the lower lever,
which it pushes aside in its turn. This movement again reverses the
caps, putting them into position. Of course the caps when in position :
are capable of rotating as usual through a small angle so as to allow the
cage to pass, and to catch it on its descent in the usual manner.
The second part of our Invention consists in self-acting sliding gates
to close the eyes of mines, which can be opened whenever required by
adjustable catches on the cages. These catches are fastened to the cage,
and are adjusted when the cage is to be opened; the cage in descending
strikes against the gate and forces it down the guides (on which it

page_text: slides). The gate is suspended by chains over pulleys, and counter-
balanced with weights, so as to be in equilibrio only when opposite the
eye. The guides of the gates are made inclined above and below the eye,
so that the gate relieves itself from the catch after the cage has passed
the eye, and returns to its normal position.
The third part of our Invention relates to safety clutches to come into
operation in the event of the rope breaking, and consists in employing
two or more of the usual pairs of clutches or cams connected together
by levers on each side of the cage instead of only one pair on each side
as hitherto arranged.