IMPROVEMENTS IN SAFETY DETACHING HOOKS FOR PREVENTING THE OVERWINDING OF MINE CAGES, AND FOR OTHER LIKE PURPOSES."
Year: 1880

page_text: LETTERS PATENT to Frederick Leonardt, of Handsworth, in the County of
Stafford, Merchant, for an Invention of "IMPROVEMENTS IN SAFETY DETACHING
HOOKS FOR PREVENTING THE OVERWINDING OF MINE CAGES, AND FOR OTHER
LIKE PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frederick Leonardt at the
Office of the Commissioners of Patents on the 5th April 1880.
FREDERICK LEONARDT, of Handsworth, in the County of Stafford, Merchant.
"IMPROVEMENTS IN SAFETY DETACHING HOOKS FOR PREVENTING THE OVERWINDING
OF MINE CAGES, AND FOR OTHER LIKE PURPOSES."
My Invention consists of the improvements, hereinafter described, in safety
detaching hooks for preventing the overwinding of mine cages, and for other like
purposes, such, for example, as preventing the overwinding of lifts, and for pre-
venting overwinding generally.
By my improvements the safety hook mechanism is made simple in construction
and use, and very efficient in action.
I will describe my Invention in connection with a mino cage.
In constructing a safety detaching hook according to my Invention I joint
together two strong parallel bars or arms, the free or unjointed ends of which are
expanded, the outer sides of the said ends having shoulders at right angles to the
arins. The inner sides of the free ends of the arins have cross semi-tubular depres-
sions, in which a loose cross bar is fitted. The pit chain is connected to the ends of
the said cross bar, and the mine cage is connected to the jointed arms in the manner
herein after described. When the jointed arms are closed upon and grasp the cross
bar, the pit chain is securely connected to the mine cage; when the jointed arms
are opened, the said cross bar can pass out of the jointed arms, and the mine cage
is thereby detached from the pit chain.
The mine cage is connected to the jointed arms in the following manner :—
About midway between the joint and ends of the jointed arins cross depressions are
made, which when the arms are closed leave a cross wedge shaped opening between
the said arms, the most acute angle of the wedge shaped opening being turned
towards the joint.
A cross wedge or wedge shaped bar is passed through this opening, and to the

page_text: ends of the said bar the mine cago is suspended by a chain. A strong collar capable
of sliding on the jointed arms when raised to its highest position fixes the free ends
of the arms in their closed position, causing them forcibly to grip the cross bar con-
nected to the end of the pit chain.
To the framing of the winding apparatus a strong cross head is fixed through a
hole in which the pit chain passes. The said hole however is not large enough to
permit of the passage through it of the collar on the jointed arms.
The action of the apparatus is as follows:- -The mino cage and pit chain having
been connected in the way described, the collar is fixed in its place at the head of
the jointed arms by means of copper wires passed through it and the jointed arms.
When by accident or neglect the mine cage is raised above the proper height, the
collar-on-the jointed arms is brought against the cross head through which the
chain passes, tho said collar is arrested, and the rising of the arms continuing,
the copper wires fixing the collar are ruptured. The said collar passing by the
rising motion of the jointed arms down the said arms towards the joint, it strikes
upon the cross wedge supporting the cage, forcing down the wedge and opening the
arms. When the arms have opened to a sufficient angle the cross bar attached to
the pit chain passes out from between the ends of the arms, thus liberating the cago
from the chain. The outer shoulders of the arms now rest upon the cross head, and
and suspend the mine cage.
By the action described the detaching of the mine cage from the pit chain at any
required height above the mouth of the pit and its safe suspension are effected
simply and with certainty.
Instead of connecting the pit chain to the mine cage by the cross-bar described,
their connection may be effected by a modification of the double wedge mechanism
described in the Specification of Letters Patent granted to me and John Craig on
the 16th day of February 1878, No. 651. I prefer however the use of the cross bar,
as described.
The application of my Invention to the prevention of the overwinding of lifts,
and to the prevention of overwinding generally, differs in no essential respect
from its application to the prevention of the overwinding of a mine cage, as herein
described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frederick Leonardt in the Great Seal Patent Office on the 27th
September 1880.
FREDERICK LEONARDT, of Handsworth, in the County of Stafford, Merchant,
"IMPROVEMENTS IN SAFETY DETACHING HOOKS FOR PREVENTING THE OVERWINDING
OF MINE CAGES, AND FOR OTHER LIKE PURPOSES."
My Invention consists of the improvements herein after described in safety
detaching hooks for preventing the overwinding of mine cages, and for other like
purposes, such for example, as preventing the overwinding of lifts and fo
preventing overwinding generally.
By my improvements the safety hook mechanism is made simple in construction
and use, and very efficient in action.
I will describe my Invention in connection with a mine cage.
In constructing a safety detaching hook according to my Invention I joint
together two strong parallel bars or arms, the freo or unjointed ends of which are
expanded, the outer sides of the said ends having shoulders at right angles to the
arins. The inner sides of the free ends of the arms have cross semi-tubular
depressions or cavities in which a loose cross bar is fitted. The pit chain is
connected to the ends of the said cross bar, and the mine cage is connected to the
jointed arins in the manner herein after described. When the jointed arms are
closed upon and grasp tho cross bar, the pit chain is securely connected to the mine
cage. When the jointed arms are opened the said cross bar can pass out of the
jointed arms, and the mine cage is thereby detached from the pit chain. The mine
cage chain is connected to the jointed arms in the following manner:-About
midway between the joint and ends of the jointed arms cross depressions are made,
which when the arms are closed leave a cross wedge shaped opening between
the said arms, the most acute angle of the wedge shaped opening being turned
towards the joint. A cross wedge or wedge shaped bar is passed through this opening,
and to the ends of the said bar the mine cage is suspended by a chain. A strong
collar capable of sliding on the jointed arms when raised to its highest position
fixes the free ends of the arms in their closed position, causing them forcibly to
grip the cross bar connected to the end of the pit chain. To the framing of the
winding apparatus a strong cross head is fixed through a holo in which the pit
chain passes. The said hole however is not large enough to permit of the passage
through it of the collar on the jointed arms.
The action of the apparatus is as follows:-The miue cage and pit chain having
been connected in the way described, the collar is fixed in its place at the head of
the jointed arms by means of copper wires passed through it and the jointed arms.
When by accident or neglect the mine cage is raised above the proper height, tho
collar on the jointed arms is brought against the cross head through which the chain
passes; the said collar is thereby arrested, and the rising of the arms continuing the
copper wires fixing the collar are ruptured. The said collar passing by the rising
motion of the jointed arms down the said arms towards the joint, it strikes upon
the cross wedge supporting the cage, forcing down the said wedgo and opening the
arms. When the arms have opened to a sufficient angle, the cross bar attached to
the pit chain passes out from between the ends of the arms, thus liberating the
cage from the chain. The outer shoulders of the arms now rest upon the cross
head and suspend the mine cage.
Instead of connecting the pit chain to the mine cage by the cross bar described,
their connection may be effected by a modification of the double wedge mechanism
described in the Specification of Letters Patent granted to me and John Craig, on
the 16th day of February 1878, No. 651; I prefer however the use of the cross bar
as described.
I will now proceed to describe with reference to the accompanying Drawing the
manner in which my Invention may be performed.

page_text: Figure 1 represents in front elevation, Figure 2 in side elevation, and Figure 3
in plan a safety detaching hook for a mine cage constructed according to my
Invention, the parts of the said hook being represented closed upon the cross bar
connected to the pit chain or rope; Figure 4 represents the hook partly opened,
and Figure 5, the same fully opened, and the cross bar and pit chain or rope
liberated from the hook, and the arms of the hook supported upon the fixed cross
hend, and the the cage thereby suspended; Figures 6 and 7 represent a modification
of the safety detaching hook, as herein after explained. The same letters indicate
the same parts in the several Figures of the Drawing. I will first describe the safety
hook represented in Figures 1, 2, 3, 4, 5, and 6. a, b, are the two parts or arms of
the safety detaching hook jointed together at c near their lower ends. The free
unjointed ends of the said arms a, b, are expanded and have the figure represented,
the outer sides of the said free ends being furnished with shoulders h, h, i, i..
Cross semi-tubular cavities or depressions are unde in the inner sides of the free
ends of the arms a, b, and in the said cavities or depressions a cross bar d is fitted,
to the ends of which cross bar the winding chain or rope is connected, as repre-
sented in Figure 2. When the arms a, b, are closed upon one another they grasp
between them the cross bar d, as represented in Figures 1, 2, and 3, and the winding
chain or rope d² is fastened to the safety detaching hook, the said hook being
connected to the mine cage in the manner herein after described. When the arms
a, b, of the hook are fully opened, as illustrated in Figure 5, the cross bar d can
pass from between them, and the mine cage is detached from the pit or winding
chain or rope. g is the top link of the mine cage chain by which the mine cage.
suspended. This mine cage chain is connected to the jointed arms a, b, in the
following manner:-In the inner faces of the arms a, b, cross depressions at a³, b³,
are made, having the figure represented, the said cross depressions when the arms a, b,
are closed leaving a cross wedge shaped opening between them. Through the wedgo
shaped opening at a, b, between the arms a, b, a wedge or wedge shaped bar fis
passed, and to the ends of the said wedge or wedge shaped bar the top link g of tho
ininc cage chain is suspended. is a strong collar sliding on the jointed arms a, b, of
the hook. The shape of the said collar is best seen in the plan, Figure 3, and sections,
Figures 1 and 2. The collar when raised to its highest position, as represented
in Figures 1 and 2, fixes the free ends of the arms a, b, in their closed position,
causing them forcibly to grip the cross bar d fastened to the pit chain or rope d².
The collar is fixed in the position represented in Figures 1 and 2 by the set of
copper wires i, j, passed through the said collar, and through the jointed arms a, b,
(see Figures 1 and 3). The use of the lower set of wires L, L, is herein after
explained. m (Figures 4 and 5) is a strong fixed cross head forming part of the
framing of the winding apparatus. Through a hole in the said cross head the pit
chain or rope passes, but the said hole is not large enough to permit of the passage
through it of the collar (see Figures 4 and 5).
is
The action of the apparatus is as follows:-The mine cage chain g and the pit
chain or rope having been connected in the manner represented in Figures 1, 2,
and 3 to the safety hook a, b, and the collar & having been fixed in its highest
position upon the said hook by the set of copper wires i, j, the apparatus is ready
for use.
When by accident or neglect the mine cage is raised above the proper
level the collar on the jointed arms a, b, of the hook is brought against the cross
hicad m (Figures 4 and 5) of the framing of the winding apparatus, and the said collar
is arrested. The rising of the arms a, b, through the opening in the cross head con-
tinuing, the copper wires j, j, are ruptured or sheared, the collar & passing by the
rising motion of the jointed arms down the said arms from the position represented in
Figure 1 to that represented in Figure 5. As the collar descends on the arms a, b,
by the rising of the said arms through the said collar, the said collar strikes the
cross wedge or bar f, to which the cage is hung, and forcing down the said wedge
opens the arms a, b. When the arms a, b, have been opened to the angle repre-
sented in Figure 5, the cross bar d attached to the pit chain or rope d² passes out
from between the ends of the arms a, b, thus liberating the cago from the winding

page_text: chain or rope. As soon as the arms have opened sufliciently wide to permit of the
escape from them of the cross bar d the shoulders h, h, of the said jointed arins rost
upon the fixed cross head m, and suspend the mine cage, as seen in Figure 5.
By the action described the detaching of the mine cage from the pit chain at any
required height above the mouth of the pit and its safe suspension are effected
simply and with certainty.
In addition to the copper wires j, j, passed through the arms a, b, and collar for
holding the latter in its closing position, a second set of copper wires marked L, L,
may be passed through the arins a, b, only at the distance below the first pair
represented in the Drawing. After the wires j, j, have been ruptured by the arrest
of the collar k, and the rising of the said arms a, b, through the said collar, the
latter is brought against the lower set of copper wires 7, 6, upon which it rests, in
case the cage is not raised above that position, as illustrated in Figure 4. When
the parts aro in the respective positions, Figure 4, the arms a, b, are opened so
wide by the operation of the wedge or wedge shaped bar fupon which the cage is
huing that the shoulders h, h, rest upon the cross head m, and suspend the cage to
the said cross head, but the arms are not opened wide enough to permit of tho
escapo of the pit chain or rope, as represented in the said Figure 4. If the raising
notion of the cage is continued the descent of the collar shears the lower set of
wires L, L, and by the action of the collar upon the wedge f the arms a, b, are fully
opened, as before explained, to permit of the release of the cross bar d, and tho
detachment of the cage from the pit chain or rope.
Figure 6 represents in front elevation, and Figure 7 in side elevation a modifi-
cation of the safety detaching hook before described.
In this modification the
cross bar is dispensed with, and the pit chain or rope q is connected to the
head n² of the wedge shaped piece n, the upper part of the two arms a, b, having
a correspondingly wedge shaped piece p made upon them, as represented in
Figure 7. After the arms a, b, have been closed upon one another, and the wedge
shaped piece n of the head n has been engaged with the wedge shaped piece p of
the two arms a, b, tho said wedge shaped parts n, p, are secured in that position by
the collar and copper wires j.j. When by the arrest of the collar, and the
raising of the wedge shaped parts n, p, through it, and the consequent rupturing
of the wires j, j, have been effected, and the wedge shaped parts have passed above
the said collar, the arms a, b, are turned upon their joint by the action of the wedgo
shaped barf to which the cage is connected. The wedge shaped part n is thereby
released from the wedge shaped part 2 of the arms a, b; the pit chain or rope is
thus disengaged from the hook, and the cage is suspended in the manner herein
before described.
A double set of wires, as represented, may be used with the modification,
Figures 6 and 7.
The application of my Invention to the prevention of the overwinding of lifts,
and to the prevention of overwinding generally, differs in no essential respect
from its application to the prevention of the overwinding of a mine cage, as herein-
before described and illustrated in the accompanying Drawing.
Having now described the nature of my Invention, and the manner in which
the same is to be performed, I wish it to be understood that I claim as my Invention
of "Improvements in Safety Detaching Hooks for Preventing the Overwinding of
Mine Cages, and for other like Purposes,"
First. Constructing the said hooks of two jointed arms, the free or unjointed ends
being expanded, and their outer sides having shoulders for suspending the cage or
lift, and their inner sides being furnished with seini-tubular cavities or recesses for
receiving a loose cross bar, to the ends of which the pit or other chain or ropo is
connected, the said jointed arms being used in combination with a sliding collar
and a fixed cross head, the several parts being constructed and operating substan-
tially as herein before described and illustrated in the accompanying Drawing;
also the modification represented in Figures 6 and 7 for connecting the pit or other
chain or rope to the safety hook.

page_text: Secondly. Connecting the mine cage or lift to the jointed arms of the safety
hook by means of a cross wedge or wedge-shaped bar passed through a corrc-
sponding shaped opening between the inner sides of the closed hook, the said cross
wedge or wedge shaped bar when the jointed arms of the hook are unfastened,
insuring the opening of the arms of the hook and the release of the pit or other
chain or rope, and the safe suspension of the cage or lift being raised, the several
parts being constructed and operating substantially as herein before described and
illustrated in the accompanying Drawing.
In witness whereof, I, the said Frederick Leonardt, have hereunto set my
hand and seal, this Seventeenth day of September, in the year of our Lord
One thousand eight hundred and eighty.
Witness,
.HUGO LOUIS SCHNEкLUTU.
Berlin.
FREDERICK LEONARDT. (L.S.)