IMPROVEMENTS IN APPARATUS FOR THE PREVENTION OF ACCIDENTS AT MINES OR PITS
Year: 1860

page_text: LETTERS PATENT to John Davis, of Cinderford, in the County of
Gloucester, Mining Engineer, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR THE PREVENTION OF ACCIDENTS AT MINES OR PITS."
Sealed the 1st November 1860, and dated the 11th July 1860.
PROVISIONAL SPECIFICATION left by the said John Davis at the Office
of the Commissioners of Patents, with his Petition, on the 11th July
1860.
I, JOHN DAVIS, of Cinderford, in the County of Gloucester, Mining
Engineer, do hereby declaro the nature of the said Invention for "IMPROVE
MENTS IN APPARATUS FOR THE PREVENTION OF ACCIDENTS AT MINES OR PITS," to be
as follows, that is to say :-
The Invention consists of apparatus to be connected with the framework of
the shaft with the view of preventing the overwinding of the chain upon the
pulley, and the consequent overdrawing of the skip, arising from the engine
not being stopped in time. The apparatus consists in attaching toothed racks
on both sides the pit, and the employment of a "gamborine" or frame of iron
working in such racks. To this "gamborine," "the cart," or skip is suspended
by chains. A box of metal containing a releasing spring is attached to the
bottom of the winding rope, and the action of the apparatus is as follows:→

page_text: In winding up the skip the rope proceeds smoothly over the pulley until the
spring box comes up to the pulley. By contact with the periphery of the
pulley the box is tilted and the spring brought into action, releasing the skip
chain and leaving the "gamborine" or frame to which the "cart" or skip
is suspended, securely resting in the teeth of the rack. The spring box passes
on with the other end of the rope, and is caught by a suitable frame placed at
any convenient position to avoid its falling to the ground.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Davis in the Great Seal Patent Office on the 10th
January 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DAVIS, of Cinderford, in the County of Gloucester, Mining Engineer, send
greeting.
WHEREAS IIer most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of July, in the year of our Lord One
thousand eight hundred and sixty, in the twenty-fourth year of Her reign,
lid, for Herself, Her heirs and successors, give and grant unto me, the said
John Davis, Her special license that I, the said John Davis, my executors,
administrators, and assigns, or such others as I, the said John Davis, my exe-
cutors, 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 APPARATUS FOR THE PREVENTION
OF ACCIDENTS AT MINES OR PITS," upon the condition (amongst others) that I,
the said John Davis, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said Inven-
tion, 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.
NOW KNOW YE, that I, the said John Davis, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say) :-

page_text: The Invention consists of apparatus to be connected with the framework of
the shaft in mines or pits, with the view of preventing the overwinding of the
chain upon the pulley, and the consequent overdrawing of the skip arising
from the engine not being stopped in time. The apparatus consists in
attaching toothed racks on both sides the pit, and the employment of a
gamborine" or frame of iron working in such racks. To this "gamborine"
the cart or skip is suspended by chains. A box of metal containing a releasing
spring is attached to the bottom of the winding rope, and the action of the
apparatus is as follows:-In winding up the skip the rope proceeds smoothly
over the pulley until the spring box comics up to the pulley. By contact with
the periphery of the pulley the box is tilted and the spring brought into action,
releasing the skip chain and leaving the "gamborine" or frame to which the
cart or skip is suspended securely resting in the teeth of the rack. The spring
box passes on with the other end of the rope, and is caught by a suitable
frame placed at any convenient position to avoid its falling to the ground.
The Invention will be better understood by reference to the accompanying
Drawings, in which like parts are represented by like letters in all the
F tre 1, Sheet A, is a side view,
Fig. 2, one
my
improvements in connection with the usual framing and pulley at the mouth
of a mine or pit. Figure 3, Sheet B, represents a section of the toothed racks
by which the "gamborine" is held suspended consequent upon the over-
winding of the chain upon the pulley and the release of the spring box;
Figure 4 shews an end view of the same. Figures 5, 6, & 7, Sheet C;
represent severally a plan, section, and end view of the spring box, and Figure 8,
Sheet B, is a section of the pulley and spring box, shewing the latter at the
moment before releasing the eye of the chain connected with the gamborine
and cart or skip.
(A) is the main pulley over which passes the ehain (B), at the end of
which is connected the spring box (C), an eye at the top of the short chain (D)
is inserted into this box and caught by the pin (E), upon which it is suspended
at the end of this chain (D) and connected by the arms (F, F,) hangs the
"gamborine (G), through which the guide ropes (H, H',) pass; suitable notches
are provided upon both sides and either end of this gamborine to catch upon
the teeth in the toothed racks (I, I, I, 1',) to prevent percussion, and from
the gamborine (G) is suspended the cart or skip (K). The toothed racks

page_text: (I, I, I', 1',) are formed of a number of short arms or levers (L) hung at one
end upon the pins (M) passing through the plates on either side, but prevented
by the pins (N) from assuming more than a horizontal position, and I find it
better that these pins (N) should be fixed higher than the centres (M), so that
the arms or levers (L) may form an angle of about thirty degrees to the hori-
zontal position, and thereby better secure the "gamborine" when it has been
over drawn.
These toothed racks (I, I, I', I',) are secured to the framing of the pulley
by the tapped bolts (0, 0, 0, 0',) passing through the beams (P, P¹,) and
secured by nuts, collars, and washers, or by any other suitable means, but
allowed of a motion sideways to liberate the gamborine when overdrawn by
being hung upon centres (Q, Q, QQ), but they are held to their work at
their lower extremities by the slides (R, R, R', R',) in which they are secured
by the keys (S, S, S', S',) until it is desired to liberate the gamborine; when
these keys are. withdrawn the short chain (D) is attached by an (S) hook to
the winding chain, and a slight movement each way the toothed racks are
drawn out of connection, and the cart or skip allowed to descend. The spring
hook (C) is formed of two limbs (Y, Y',) of metal, iron, or steel, hinged at
their upper extremities to the end of the chain (B), and upon one limb are
formed the shoulders (T, T¹), and a rivet or pin (E) is burred and screwed to
the back, working into a box (X) formed upon the other limb (Y'), and
resting in it: when the load or weight is directly below these two limbs are
held together by the spring (V) fastened to one limb, and hooking over a
connecting piece (W) on the other limb, so that as long as the spring box is
vertical the weight of the skip is suspended on the rivet or pin (E), but when
the box comes up to the pulley (A) and commences revolving over it, the
weight of the cart or skip acts upon the box (X) by drawing it down from,
the pin (E) on the limb (Y), which is upheld from the periphery of the pulley
by the shoulders (T, T), and thereby liberates the eye of the chain (D), and
allows the gamborine to remain securely held by the toothed racks while the
chain to which the hook or box is attached continues to be wound up. Should
the periphery of the pulley over which the rope winds be concave or of any
section other than the one shewn, suitable flanges will have to be formed upon
the shoulders (T, T¹).
In pits in which wood guides are used the toothed racks must be brought
nearer to one another in the frame of the pit, and the notches formed on the
beam or gamborine, and they must be inside the guides.
Having thus described the nature of my said Invention, and in what manuer

page_text: the same is to be performed, I do not confine myself to the precise details herein
described and illustrated, but that which I claim as my Invention and desire
to have secured to me by the herein-before in part recited Letters Patent
is, the improvements in apparatus for the prevention of accidents at mines or
pits from overwinding, substantially as herein set forth and specified.
In witness whereof, I, the said John Davis, have hereunto set my
hand and seal, this Seventh day of January, in the year of our Lord
One thousand eight hundred and sixty-one.
Witness,
ABRAHAM HARTLAND.
JOHN DAVIS. (L.B.)