IMPROVEMENTS IN SAFETY APPARATUS FOR MINE CAGES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO LIFTS For WAREHOUSES, HOTELS, ANd other PlacES
Year: 1878

page_text: LETTERS PATENT to Frederick Leonardt, of Birmingham, in the County of
Warwick, Merchant and Manufacturer, and John Craig, of Birmingham afore-
said, Machinist, for the Invention of "IMPROVEMENTS IN SAFETY APPARATUS
FOR MINE CAGES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO LIFTS For
WAREHOUSES, HOTELS, ANd other PlacES."
Sealed the 30th July 1878, and dated the 16th February 1878.
PROVISIONAL SPECIFICATION left by the said Frederick Leonardt and
John Craig at the Office of the Commissioners of Patents on the 16th
February 1878.
FREDERICK LEONARDT, of Birmingham, in the County of Warwick, Merchant
and Manufacturer, and JOHN CRAIG, of Birmingham aforesaid, Machinist. " IM-
PROVEMENTS IN SAFETY APPARATUS FOR MINE CAGES, WHICH IMPROVEMENTS ARE
ALSO APPLICABLE TO LIFTS FOR WAREHOUSES, HOTELS, AND OTHER PLACES."
Our Invention consists of the safety apparatus herein-after described to be
applied to mine cages, by the use of which apparatus the cage is suspended in the
pit or mine shaft on the accidental breaking of the winding chain or rope, and the
overwinding of the mine cage is prevented.
The said improvements are also applicable to lifts for warehouses, hotels, and
other places.
We will describe our improvements in connection with a mine cage.
On opposite sides of the mine shaft we fix guide rods, and on opposite sides of
the cage we fix tubes extending from the top to the bottom of the cage. Through
these tubes the guide rods described pass, the tubes in the cage in its ascent and
descent sliding upon the said rods. On the under side of the bottom of the cage
a strong bracket is fixed, the vertical concave face of the said bracket bearing
against one of the guide rods. To the under side of the bottom of the cage and
immediately opposite the before described bracket a safety lever is jointed, the
short arm of the said lever being eccentric to the axis on which it turns, and
having a concave face or termination. The concave face of the short arm of the

page_text: safety lever bears against the side of the guide rod opposite to that against which
the before-mentioned bracket bears. When the long arm of the safety lever is
depressed its short arm comes against the guide rod, and the said guide rod is
firmly gripped between it and the bracket, and the cage is no longer capable of
sliding on the guide rods. The safety lever when at liberty to move always
assumes the position described, that is, its locking or gripping position, by the
action of a spring or weight on its long arm. A vertical rod connected to the end
of the long arm of the safety lever ascends through the bottom and top of the
cage, and is connected at its upper end to a chain, which chain, with the suspending
chains of the cage, are hooked or fastened to the winding chain or rope. The first-
mentioned chain, which we will call the safety chain, is in a state of tension so
long as the cage hangs from the winding chain or rope, and when in that state
raises the long arm of the safety lever and prevents it gripping the guido rod.
When however the winding chain or rope breaks, the tension on the safety chain
being relaxed, and the safety lever being now at liberty to move, its spring or
weight immediately brings it into the gripping position, and the cage is brought to
rest and firmly suspended in the mine shaft.
In order to prevent overwinding the cage is suspended by means of two plates,
one connected to the winding chain or rope, and the other to the suspending and
safety chains at the top of the cage. These two plates are wedge shaped on their
inner faces, the base of the wedge being at the bottom of the plate suspending
from the winding chain, and the base of the wedge on the other plate being at its
top. When the wedge shaped faces of these two plates are placed together, and a
sliding locking collar drawn over them, they are incapable of separating.
The said sliding locking collar may be fixed in its place by a light wire or other
pin passing through it and the two wedge shaped plates.
The winding chain or rope passes through an opening in a cross head fixed a
short distance below the winding pulley, the said opening not being sufficiently
large to permit of the passage through it of the before-mentioned sliding locking
collar.
When, by inadvertence or carelessness, the cage is wound above the proper
height, the locking collar coming against the cross head described is stripped from
off the wedge shaped plates, and the cage is detached from the winding chain or
rope. The safety lever now comes into operation, and suspends the cage as before
described.
Instead of cylindrical guide rods square guide rods may be fixed against the
sides of the mine shaft. In this case the suspension of the cage is effected by an
excentric on the under side of the cage having a toothed face engaging against the
face of one of the guide rods. This eccentric is forced against the guide rod by
means of a connecting rod and coiled spring. A cord or chain secured to the said
connecting rod passes over pulleys to the top of the cage, and is there connected to
the winding chain.
When the cage is suspended by the winding chain the safety cord or chain
connected with the eccentric is in a state of tension, and the eccentric is drawn
out of action,
When, by the breaking of the winding chain, the tension on the safety cord or
chain is removed, the eccentric comes into action, and pressing against the guide
rod suspends the cage in the mine shaft.
The application of our Invention to lifts differs in no essential respect from its
application to mine cages herein-before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frederick Leonardt and John Craig in the Great Seal Patent Office
on the 9th August 1878.
FREDERICK LEONARDT, of Birmingham, in the County of Warwick, Merchant
and Manufacturer, and JOHN CRAIG, of Birmingham aforesaid, Machinist.
"IM-
PROVEMENTS IN SAFETY APPARATUS FOR MINE CAGES, WHICH IMPROVEMENTS ARE
ALSO APPLICABLE TO LIFTS FOR WAREHOUSES, HOTELS, AND OTHER PLACES."
Our Invention consists of the safety apparatus herein-after described to be
applied to mine cages, by the use of which apparatus the cage is suspended in the
pit or mine shaft on the accidental breaking of the winding chain or rope, and the
overwinding of the mine cage is prevented.
The said improvements are also applicable to lifts for warehouses, hotels, and
other places.
We will describe our improvements in connection with a mine cage.
On opposite sides of the mine shaft we fix guide rods, and on opposite sides of
the cage we fix tubes extending from the top to the bottom of the cage. Through
these tubes the guide rods described pass, the tubes in the cage in its ascent and
descent sliding upon the said rods. On the under side of the bottom of the cage
a strong bracket is fixed, the vertical concave face of the said bracket bearing
against one of the guide rods. To the under side of the bottom of the cage and
immediately opposite the before-described bracket a safety lever is jointed, the
short arm of the said lever being eccentric to the axis on which it turns, and having
a concave face or termination. The concave face of the short arm of the safety
lever bears against the side of the guide rod opposite to that against which the
before-mentioned bracket bears. When the long arm of the safety lever is de-
pressed its short arm comes against the guide rod, and the said guide rod is firmly
gripped between it and the bracket, and the cage is no longer capable of sliding on
the guide rods. The safety lever when at liberty to move always assumes the
position described, that is, its locking or gripping position, by the action of a spring
on its long arm. A vertical rod connected to the long arm of the safety lever
ascends through the bottom and top of the cage, and is connected at its upper end
to a chain, which chain, with the suspending chains of the cage, are hooked or
fastened to the winding chain or rope. The first-mentioned chain, which we will
call the safety chain, is in a state of tension so long as the cage hangs from the
winding chain or rope, and when in that state raises the long arm of the safety
lever and prevents it gripping the guide rod. When however the winding chain
or rope breaks, the tension on the safety chain being relaxed, and the safety lever
being now at liberty to move, its spring immediately brings it into the gripping.
position, and the cage is brought to rest and firmly suspended in the mine
shaft.
In order to prevent overwinding the cage is suspended by means of two plates,
one connected to the winding chain or rope, and the other to the suspending and
safety chains at the top of the cage. These two plates are wedge shaped on their
inner faces, the base of the wedge being at the bottom of the plate suspended from
the winding chain, and the base of the wedge on the other plate being at its top.
When the wedge shaped faces of these two plates are placed together, and a sliding
locking collar drawn over them, they are incapable of separating.
The said sliding locking collar may be fixed in its place by a light wire or other
pin passing through it and the two wedge shaped plates.
The winding chain or rope passes through an opening in a cross head fixed a
short distance below the winding pulley, the said opening not being sufficiently
"
}

page_text: large to permit of the passage through it of the before-mentioned sliding locking
collar.
When, by inadvertence or carelessness, the cage is wound above the proper
height, the locking collar coming against the cross head described is stripped from
off the wedge shaped plates, and the cage is detached from the winding chain or
rope. The safety lever now comes into operation, and suspends the cage as before
described.
Instead of cylindrical guide rods square guide rods may be fixed against the
sides of the mine shaft. In this case the suspension of the cage is effected by an
eccentric having a toothed face engaging against the face of one of the guide rods.
This eccentric is forced against the guide rod by means of a connecting rod and
coiled spring. A cord or chain secured to the said connecting rod passes over
pulleys to the top of the cage, and is there connected to the winding chain.
When the cage is suspended by the winding chain the safety cord or chain
connected with the eccentric is in a state of tension, and the eccentric is drawn out
of action.
When, by the breaking of the winding chain, the tension on the safety cord or
chain is removed the eccentric comes into action and pressing against the guide rod
suspends the cage in the mine shaft.
The application of our Invention to lifts differs in no essential respect from its
application to mine cages herein-before described.
We will now proceed to describe, with reference to the accompanying Drawings,
the manner in which our Invention may be performed.
Figure 1 represents in front elevation, partly in vertical section, and Figure 2
in side elevation, partly in vertical section, a mine cage and parts connected with it
containing safety apparatus constructed according to our Invention.
Figure 3 represents a plan of under side of the cage and parts of the safety
apparatus.
Figures 4 and 5 represent in vertical section one of the safety levers of the appa-
ratus, and Figures 6 and 7 represent in vertical section the other safety lever of the
apparatus.
In Figures 4 and 6 the safety levers are represented out of action, and in Figures 5
and 7, in action.
Figures 3, 4, 5, 6, and 7 are drawn double the scale of Figures 1 and 2.
The other Figures represent a modification of the safety lever and the mechanism
for preventing overwinding.
The same letters of reference indicate the same parts in Figures 1, 2, 3, 4, 5, 6,
and 7.
We have shown in the said Figures 1, 2, 3, 4, 5, 6, and 7 two safety levers com-
bined in the same cage, one lever being applied to one and the other lever to the
other of the two guide rods in the mine shaft; but we wish it to be understood that
either of the said levers may be used alone in the mine cage instead of in com-
bination as represented, and two of the same kind of levers may be used in the same
cage.
a, b, are the fixed guide rods situated on opposite sides of the mine shaft c, and
extending from the bottom to above the top of the said mine shaft; d is the mine
enge, and e, e, are tubes fixed on opposite sides of the cage d, and extending from the
top to the bottom of the cage, as represented. Through the tubes e, e, in the cage
the guide rods a, b, pass, the tubes e, e, on the motion of the cage sliding on the said
rods. On the under side of the cage (see Figure 3) safety levers are arranged for
acting respectively upon the fixed guide rods
a, b.
We will first describe the construction of the safety lever which presses upon the
guide rod a.
The said safety lever is marked f, f, and is used in conjunction with
a strong bracket g fixed to the bottom of the cage, the said strong bracket having a
concave face which bears against the guide rod a (see Figure 3). The curved end
of the short arm f of the the said safety lever is eccentric to the centre ƒ³, on

page_text: which it turns, and the said curved end has a concave face; the said concave face of
the short arm f, when the safety lever is brought into action, bearing against the
side of the guide rod a opposite to that against which the bracket g bears, as best
seen in Figure 3. A spring h bearing upon the long arm f2 of the safety lever tends
to force the short gripping arm finto its gripping or locking position when at liberty
to move. To the end of the long arm f2 of the safety lever a rod i is connected..
This rod ascends through the bottom of the cage and is connected at its upper end
to a safety chain k, which safety chain k with the other suspending chains of the. :
cage are hooked or fastened to the winding rope or chain l, as represented in
Figures 1 and 2. So long as the cage d hangs from the winding chain or rope
the safety chain k connected with the lever ff, is in a state of tension, and the
said chain raises the long arm f2 of the safety lever into the position represented in
Figures 1, 2, 3, and 4, and takes the said safety lever out of action and prevents it
gripping the guide rod a. When however the winding chain or rope breaks, the
tension on the safety chain k being relaxed and the safety lever being now at liberty
to move, its spring h immediately brings it into the gripping position represented
in Figure 5, and the guide rod a is thereby firmly gripped between it and the
bracket 9, and the cage a is brought to rest and firmly suspended in the mine
shaft.
We will now describe the construction of the other safety lever which acts in a&
like manner to the safety lever ff, upon the opposite guide rod b. The safety
lever pressing on the guide rod b consists of an eccentric or cam m having motion
on the centre n, the acting face of the said eccentric or cam being concave, as best
seen in Figure 3. A connecting rod p is jointed to the said cam or eccentric m,
and the latter is forced, when at liberty to move against the guide rod b by the
coiled spring q around the said connecting rod, one end of the said spring taking
its abutinent against a shoulder on the said rod p, and the other end against the
support p³ on the bottom of the cage. The cam or eccentric m of the safety lever
works in the strong bracket r, having a concave face, the guide rod b passing through
the said bracket (see Figure 3). To the end of the rod p a chain or cord p³ is
secured, which chain or cord passes over the pulleys p, p, and is connected to the
winding chain (see Figures 1 and 2).
When the tension on the chain p³ is maintained by the winding chain 7, the
eccentric or acting part m of the safety lever is withdrawn from the guide rod b
and the cage is free to rise or fall upon the guide rod, as represented in Figure 6,
the coiled spring q being compressed. When however by the breaking of the
winding chain the tension on the safety chain p³ is removed, the eccentric m is
forced into action by the coiled spring q and rod p, and the said eccentric pressing
against the guide rod b causes the latter to be firmly gripped between the said
eccentric m and the bracket r, as seen in Figure 7. The cage is thereby suspended
in the mine shaft.
Figure 8 represents in vertical section, and Figure 9 in plan, partly in horizontal
section, a lift for warehouses, hotels, and other places, provided with safety
mechanism constructed according to our Invention. a² is the lift, and a³ is a frame
or upright, between which the lift works. On opposite sides of the frame a³ are
square or angular guides or guiding rods a made of wood, on which guides the lift
rises and falls (see the plan and section, Figure 9).
The safety levers f, f, for suspending the lift in the frame or uprights a³ on the
breaking of the raising rope or chain is constructed essentially in the same way as
the safety lever represented in Figures 4 and 5, but the end of its eccentric arm f
is provided with a toothed face for engaging with the face of the wooden guide
rod at. The toothed eccentric face of the arm f of the safety lever is forced against
the guide rod at, when at liberty to move, by the coiled spring h situated under the
long arm of the said lever. The said long arm of the lever is connected to
the raising chain or rope of the lift by the safety chain k in the manner herein-
before described.

page_text: When the lift is suspended in the frame as by the raising chain or rope l, the
eccentric end of the lever is withdrawn out of action, as represented in Figure 8,
but on the breaking of the raising chain or rope, the tension on the safety chain k
being removed, the toothed eccentric arm f is forced into action by the spring h,
and its toothed face engaging firmly with the wooden guide rod a suspends the
lift in its frame.
may be
The arrangement of the parts of the lift represented in Figures 8 and 9
applied to mine cages, and the arrangements of the parts of the mine cage repre-
sented in Figures 1 to 7 may also be applied to lifts.
We will now describe our disengaging apparatus for preventing the overwinding
of the mine cage or lift. The said disengaging apparatus is represented in con-
nection with a mine cage in Figures 1 and 2, and with a lift in Figure 8, and
separately drawn to a larger scale in Figures 10, 11, 12, and 13. Figure 10 repre-
sents the disengaging apparatus in front elevation and plan; Figure 11, a side
elevation of the same; and Figure 12, a section of the same. Figure 13 exhibits
the sliding collar of the disengaging apparatus in the act of being stripped from the
wedge-shape plates of the said disengaging apparatus.
The said disengaging apparatus for preventing overwinding consists essentially of
the two shaped plates t, u, the upper plate u being connected to the winding
chain l, and the lower plate t being connected to the suspending and safety chains
of the cage or lift, in the manner illustrated in Figures 1, 2, and 8.
The position of the wedge-shaped parts on the inner faces of the two plates, and
the manner in which the wedge-shaped parts are engaged together, are shown in
Figures 11 and 12. The wedge-shaped faces of the two plates t, u, being placed
together, a sliding locking collar v is drawn thereon, and the said collar fixed in its
place by a light wire or other pin w passed through the said collar and the two
plates t, u. By means of the said collar the two plates are locked firmly together,
and are incapable of separating so long as the collar v occupies the position repre-
sented in Figures 10, 11, and 12. x is a cross head or bracket situated a short
distance below the winding pulley y. In the said cross head or bracket x is a hole
through which the winding rope or chain / passes, the said hole not being sufficiently
large to permit of the passage through it of the sliding locking collar v.
When by inadvertence or carelessness the cage or lift is wound above the proper
height, the locking collar v coming against the cross head or bracket is stripped
from off the wedge-shaped plates t, u, (see Figure 13), and the cage or lift is detached
from the winding chain or rope, and the safety lever or levers herein-before described
is or are brought into operation, and the cage or lift is suspended.
Having now described the nature of our Invention, and the manner in which the
same is to be performed, we wish it to be understood that we claim as our Invention
of improvements in safety apparatus for mine cages and for lifts for warehouses,
hotels, and other places,-
First. The arrangement or combination of the parts of the safety lever or
mechanism, herein-before described, and illustrated in Figures 1, 2, 3, 4, and 5 of the
accompanying Drawings, for suspending the mine cage or lift on the breaking of the
winding chain or rope.
•
Secondly. The arrangement or combination of the parts of the safety lever or
mechanism, herein-before described, and illustrated in Figures 1, 2, 3, 6, and 7 of the
accompanying Drawings, for suspending the mine cage or lift on the breaking of the
winding chain or rope.
Thirdly. The arrangement or combination of the parts of the safety lever or
mechanism, herein-before described, and illustrated in Figures 8 and 9 of the accom-
panying Drawings, for suspending the mine cage or lift on the breaking of the
winding chain or rope.
Fourthly. The arrangement or combination of the parts of the disengaging
damibed and illudunted in Timna 1
° 10 11 10

page_text: and 13 of the accompanying Drawings, for preventing the overwinding of the mine
cage or lift.
In witness whereof, I, the said Frederick Leonardt, have hereunto set my hand
and seal, this Second day of August, in the year of our Lord One thousand
eight hundred and seventy-eight.