IMPROVE- MENTS IN APPARATUS FOR RELIEVING WIRE ROPES FROM STRAIN WHEN USED IN LIFTING AND LOWERING WEIGHTS."
Year: 1865

page_text: LETTERS PATENT to John Gibson, of the Ryehope Colliery, near Sunder
land, in the County of Durham, Engineer, for the Invention of "IMPROVE-
MENTS IN APPARATUS FOR RELIEVING WIRE ROPES FROM STRAIN WHEN USED
IN LIFTING AND LOWERING WEIGHTS."
PROVISIONAL SPECIFICATION left by the said John Gibson at the
Office of the Commissioners of Patents, with his Petition, on the 30th
January 1865.
I, JOHN GIBSON, of the Ryehope Colliery, near Sunderland, in the County of
Durham, Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS FOR RELIEVING WIRE ROPES FROM STRAIN WHEN
USED IN LIFTING AND LOWERING WEIGHTS," to be as follows:-
My Invention relates principally to the lifting of weights in coal mines,
and consists in the application to the bearings of the lifting pulley of laminated
springs resting on elastic beds or cushions, such springs being of sufficient
reactionary power to take the usual strain off the lifting wire rope, and thereby
to relieve it from all strain except that of tension. For this purpose the
springs are applied under the bearings of the pulley, and so as to be capable

page_text: of working within metal boxes secured to the ordinary frame for supporting
the pulley. These springs each consist of a series of steel plates suitably fixed
together and forming a spring of the requisite strength, which rests at each
end on rollers (preferred to be of cast steel) in order to prevent the friction
of the spring when working. These rollers are inserted in cavities formed
in the bed plate of the box under each bearing. The springs also rest on
cushions of india-rubber confined within metal guides, the upper edges of
which are curved to correspond with the concave form of the bottom plate of
the spring; and the cushion is of sufficient depth to extend above the top of
the guide plates, so as to leave a space for deflection between the bottom
plate of the spring and the top of the guide plates, such space being filled
with india-rubber.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Gibson in the Great Seal Patent Office on the 29th
July 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GIBSON, of Ryehope Colliery, near Sunderland, in the County of Durham,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of January, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Gibson, Her special licence that I, the said John Gibson,
my executors, administrators, and assigns, or such others as I, the said
John Gibson, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "In-
PROVEMENTS IN APPARATUS FOR RELIEVING WIRE ROPES FROM STRAIN WHEN USED
IN LIFTING AND LOWERING WEIGHTS," upon the condition (amongst others) that
I, the said John Gibson, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner

page_text: 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 Gibson, do hereby declare
the nature of my 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) :-
:―
My Invention of "Improvements in Apparatus for Relieving Wire Ropes from
Strain when used in Lifting and Lowering Weights" relates principally to the
lifting of weights in coal mines, and consists in the application to the bearings
of the lifting pulley of laminated springs resting on elastic beds or cushions,
such springs being of sufficient reactionary power to take the usual strain off
the lifting wire rope, and thereby to relieve it from all strain excopt that of
tension. For this purpose the springs are applied under the bearings of the
pulley, and so as to be capable of working within metal boxes secured to the
ordinary frame for supporting the pulley. These springs each consist of a
series of steel plates suitably fixed together and forming a spring of the
requisite strength, which rests at each end on rollers (preferred to be of
cast steel) in order to prevent the friction of the spring when working. These
rollers are inserted in cavities formed in the bed plate of the box under each
bearing. The springs also rest on cushions of india-rubber confined within
metal guides, the upper edges of which are curved to correspond with the
concave form of the bottom plate of the spring, and the cushion is of sufficient
depth to extend above the top of the guide plates so as to leave a space for
deflection between the bottom plate of the spring and the top of the guide
plates, such space being filled with india-rubber. And there are compensating
volute springs fixed in the centre under the laminated springs for the purpose
of restoring the latter to their position of the removal of the downward
pressure on them.
Having thus stated the nature of the said Invention, I will proceed to
describe more particularly in what manner the same is to be performed by
reference to the accompanying Drawings, in which are represented the parts
Lahore zaferred to

page_text: plan of the metal box in which the spring works; Fig. 4 is a plan of the
carriage; Fig. 5 is a side elevation of the bearings, with one of the side plates
of the box removed; Fig. 6 shews one of the guides; and Fig. 7 is a plan of
the elastic bed or cushion confined within the guides. In these several Figures
the same letters of reference indicate corresponding parts.
A is the axle of the main pulley, over which the rope runs; B is a malleable
iron carriage fitted with brasses in the ordinary manner, such carriage being
firmly fixed on the spring with bolts and cross bars as shewn in Fig. 2; C is
the spring over which the bearings or carriages B are fixed, and on which
they rest, these springs are formed as shewn of a series of curved plates; D is
a metal box within which the spring works; E, E, are malleable iron
guides fitted under the spring, which guides are curved on their upper side
to correspond with the curved form of the spring, and there is a space left
between the spring and the guide plates for deflecting, such space being
filled in with india-rubber or other suitable elastic material, thereby
forming an elastic bed or cushion F for the spring to rest upon; G is a
volute spring fixed underneath the laminated spring C for the purpose of
acting as a compensating spring to the latter; H, H, are rollers preferred to
be of cast steel, on which the spring C rests at each end; I is a guide rod to
support the bearing or carriage B; J is a wooden frame on which the whole
apparatus is fixed.
From the foregoing description it will be evident that when a strain is
brought on the axle A of the lifting pulley it will cause a downward pressure
on the spring C, on which the bearing or carriages B rest, and the deflection
of the spring due to the pressure upon it will be resisted as required by the
elastic bed or cushion F and the volute spring G, and the extent of the de-
flection of the spring C will be limited by the space left between the bottom of
the spring and the top of the metal guides E, E. It will also be seen that the
friction of the spring C in working will be diminished by its ends resting on
the rollers H, H, and that the spring will be restored to its original position
by the compensating reaction of the volute spring G as soon as the strain is
removed from the axle A,
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, I hereby declare that I do not claim as of my
Invention any of the parts represented and described except as herein-after
stated; but what I do claim as of my Invention is the application to the
hearings of lifting pulleys of laminated springs combined with elastic beds or
cushions, and compensating volute springs, for the purpose of relieving wire

page_text: ropes in the manner herein-before described from the strain to which they are
ordinarily exposed in lifting and lowering weights.
In witness whereof, I, the said John Gibson, have hereunto set my
hand and seal, the Twenty-sixth day of July in the year of our Lord
One thousand eight hundred and sixty-five.
Witness,
RALPH BROWN,
Ryehope Colliery.
(L.S.) JOHN GIBSON.