IMPROVEMENTS IN CRANES AND HOISTING MACHINERY
Year: 1879

page_text: LETTERS PATENT to James Shanks and James Gordon Lyon, both of Arbroath,
in the County of Forfar, Engineers, for the Invention of "IMPROVEMENTS IN
CRANES AND HOISTING MACHINERY."
PROVISIONAL SPECIFICATION left by the said James Shanks and James
Gordon Lyon at the Office of the Commissioners of Patents on the 18th March
1879.
JAMES SHANKS and JAMES GORDON LYON, both of Arbroath, in the County of
Forfar, Engineers. IMPROVEMENTS IN CRANES AND HOISTING MACHINERY."
Our Invention relates to the gearing of cranes; and it consists of a pair of
engines fixed to the side frames of the crane, on the crank shaft of which engines
is secured a pair of friction discs, between which is placed a wooden or other roller,
which is fixed to the end of a shaft having on it a steel worm gearing into or
giving motion to a worm wheel on the barrel shaft. By shifting the roller from
one side of the centre of the crank shaft to the other a reversing motion is
obtained.
A motion such as above described modified in its details according to circum-
stances is provided or applied to the various motions of lifting, slewing, jibbing, or
travelling the crane.
The objects to be gained are, almost an unlimited number of speeds of lift; a
noiseless movement in lifting, slewing, and the like; and an effective reversing
motion.
The Invention is also applicable to hoisting machinery.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Shanks and James Gordon Lyon in the Great Seal Patent
Office on the 18th September 1879.
JAMES SHANKS and JAMES GORDON LYON, both of Arbroath, in the County of
Forfar, Engineers. "IMPROVEMENTS IN CRANES AND HOISTING MACHINERY.'
Our said Invention relating to cranes and hoisting machinery has for its object
providing increased facilities for varying the speed of the different motions of the
crane, and also for reversing the motion as required. .
In carrying out our said Invention as applied to the motion of the barrel or
barrels we employ a disc or discs on the crank shaft, and a friction roller (by
preference of wood) on another shaft, which also carries a worm or worms engaging
with a worm wheel or worm wheels on the barrel shaft or shafts.
The roller which is in contact with the disc or discs receives motion therefrom
and transmits it to the barrel or barrels. By moving the roller on its shaft to a
different position relatively to the centre of the disc or discs the speed of the barrel
or barrels is varied as required. By moving the roller beyond the centre of the
disc or discs the motion is reversed. Two engines fitted with link motions may be
employed for driving the crank shaft, in which case the motion may be reversed
by reversing the engines in the ordinary manner, the arrangement of friction roller
and disc or discs being used for varying the speed only. When however a single
engine only or two engines without reversing gear are used the friction roller and
disc or discs may be utilized for reversing as well as for varying the speed.
The Invention is applicable to the various motions of lifting, slewing, jibbing, or
travelling the crane, and also to hoisting machinery generally.
And in order that our said Invention may be fully understood we shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of the accompanying Drawings represents a longitudinal section of a
portion of a steam crane having applied thereto the improvements which form the
subject of the said Invention, according to one mode of carrying out the same;
Figure 2 is a transverse section corresponding to Figure 1; Figures 3 and 4
represent in transverse section modifications of the arrangement illustrated in
Figures 1 and 2.
In the arrangement illustrated in Figures 1 and 2 two engines A are used, the
same being arranged one at each side of the crane and attached to the side frames B,
and being each provided with two eccentrics a, a, on the crank shaft C with
reversing gear D and all the usual appurtenances of ordinary steam engines, and
the motion of the crank shaft C is reversed by means of the reversing gear D in
the usual manner. In order to enable the speed to be varied as required we apply
the improvements hereinbefore referred to and next hereinafter described. On the
crank shaft C are mounted two discs E, E¹, the former (E) being fast on the shaft,
and the latter E' loose on the shaft and forced towards the disc E by a helical
spring b. Between and in contact with the discs E, E¹, is a roller F, mounted so as
to be capable of being moved along a shaft G, and so as when rotated cause such
shaft to turn therewith, the disc E¹ being simply used to maintain the roller in
intimate contact with the disc E. Assuming the engines to have been started in
the desired direction motion is imparted to the crank shaft C and thence to the
disc E, which by frictional contact with the roller F transmits motion to the same,
and thence to the barrel H or H' through the intervention of the worm gearing I or I¹,
the latter being respectively thrown into or out of gear by the aid of clutches K, K¹.
By moving the roller F nearer to or further from the centre of the discs E, E¹, the
speed of the barrels is varied as required.

page_text: When a single engine without reversing gear is used the discs E, E¹, may be
arranged in the manner represented in Figure 3. In this case the crank shaft C
carrying the fast disc E terminates at one end at c, the loose disc E' is mounted on
a stud centre C, and the roller shaft G is prolonged downwards, its lower extremity
turning in a foot step bearing d. The motion may then be reversed by moving the
roller F to the opposite side of the crank shaft, as indicated by the dotted lines in
Figure 3, the facilities for varying the speed being the same as before. In some
cases the roller shaft itself may be arranged to move, the roller being fast upon the
shaft.
The modification illustrated in Figure 4 may be used when two engines are
employed, which in this case are not necessarily fitted with reversing gear. Both
the discs E and E' are loose upon the shaft C, but either of the two is capable of
being made fast thereon by the act of operating the clutches L, L'.
Both discs are
also fitted with helical springs b, b, and when one of the discs is made fast upon the
shaft the other disc forms the loose disc proper for maintaining the roller F in
intimate contact with the fast disc. It will thus be apparent that one of the
clutches is in gear and the other disengaged the fast disc imparts motion to the
roller, and that by reversing the clutch action the other disc becomes the driver and
the motion is accordingly reversed. The speed is varied by moving the roller F
longitudinally along its shaft G, as in the arrangements illustrated in Figures 1
and 2 and Figure 3.
Our said Invention is also applicable to the motions of slewing, jibbing, or
travelling the crane, and to hoisting machinery generally, in a manner which will
be perfectly understood from the examples of the application hereinbefore given.
By its use we obtain an almost unlimited variety of speeds, a noiseless movement,
and an effective reversing motion.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried into
effect, we would observe in conclusion that what we consider to be novel and original,
and therefore claim as the Invention secured to us by the herein before in part
recited Letters Patent is,-
The employment in cranes and hoisting machinery of friction discs in combina-
tion with a friction roller, the same being arranged so as to operate substantially
in the manner and for the purposes hereinbefore described.
In witness whereof, we, the said James Shanks and James Gordon Lyon, have
to this our Specification set our hands and seals, this Thirteenth day of
September, One thousand eight hundred and seventy nine..
JAMES SHANKS.
(L.S.)
JA8. GORDON LYON. (L.S.)