Improvements in Safety Stop Apparatus for Mining Cages.
Year: 1893

page_text: COMPLETE SPECIFICATION.
Improvements in Safety Stop Apparatus for Mining Cages.
I, WILHELM ALBRECHT, of 20 Bergstrasse, Goettelborn, Saarbruck, in the
Empire of Germany, Engineer, 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, reference being had to the accom-
panying drawings and to the figures and letters marked thereon:-
The present invention relates to a safety stop apparatus for mining cages which
serves to prevent the cage from running down when, during the hoisting of it, the
engine should, from any cause, be stopped. The main features required for the
safety apparatus are that it shall automatically permit of the rising of the cage and
automatically assume the locking or stopping position when hoisting, and it is also
necessary that the safety stop should be readily freed in a downward direction for
lowering the cage when the latter is under full load without first having to raise
the cage.
The safety stop apparatus herein described fulfils these requirements in a
satisfactory manner, and through the great simplicity of its construction, it gives
more security than the hydraulic apparatus hitherto in use.
In the accompanying drawings
Figure 1 is a front elevation and Figure 2 is a cross section of my improved
safety stop apparatus.
C is a shaft, which is supported in two bearings K K, which are bolted firmly
to a supporting beam which is firmly secured in the mining shaft. Between the
two bearings is a steel thumb piece or stop A. mounted movably on the shaft C;
this thumb piece presents its stop towards the mining shaft. The strengthening
web of the stop B is provided with a slot D formed concentrically with the
spindle C, and in this slot is freely fitted a steel pin E carrying on each end a
lever F. The lower extremities of these levers F are connected together by the
bolt G, which latter carries between the levers a roller H. On each side of the
thumb piece or stop and between it and the bearings K K, is another lever T,
which levers are rigidly keyed on the spindle C and connected by means of the
bolt G to the levers FF, so as to form the double link levers F, G, T. The lower
hole of the levers T is slightly elongated, as shown by the dotted lines, so as to
allow the bolt G to move freely therein. All the parts are secured together on the
bolt G by means of two nuts provided with cross pins. The roller H bears on an
inclined part M provided on the bearing plate L.
Opposite sides of the mining shaft are each provided with a spindle C carrying
the parts hereinbefore described. The two spindles C can be turned simultaneously
by a suitable lever mechanism, which is not shown but which will be readily
understood.
When the cage is being hoisted, it lifts the stops B into the dotted position A',
see Figure 2, which allows free passage to the cage. As soon as the cage has
risen past them the stops B at once fall into their normal position. If now the
cage should begin to descend, it will settle down on the stops B and thus be
prevented from any further descent. The stop B is prevented from turning down-
wards through the links or levers F, as the stop bears on the steel pin E and this
latter transfers the pressure, through the medium of the levers F and bolt G, to
the roller H, which bears on the inclined plane M. It is impossible_for the
roller H to run up the inclined plane M, as the angle formed by the line E G and
the inclined plane M is either a right angle or less. In order to lower the cage it
is only necessary to turn the spindles C by means of the lever mechanism before
referred to, when, through the medium of the levers T, the roller H is made to

page_text: ascend the inclined plane M. The stop piece is thereby brought into the position A³
shown by dotted lines and the roller into the position G', which allows the cage to
be lowered without having first to lift it to allow of the stops being withdrawn
from its path.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A safety stop apparatus for mining cages characterized by a stop piece B
which is in connection with a roller H running on an inclined plane in such a
manner that in the descent of the cage, the passage beyond the stop B is only
possible after the spindle C in connection with it has been turned, for which
purpose the roller H has to be forced up the inclined plane, substantially as herein
described and illustrated in the drawings.
2. In safety stop apparatus for mining cages, the peculiar combination and
arrangement of apparatus, substantially as herein shown and described.
Dated this 3rd day of January 1893.
WILHELM ALBRECHT,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.