IMPROVEMENTS IN CRANES OR LIFTING AND LOWERING APPARATUS."
Year: 1854

page_text: LETTERS PATENT to Alexander Law, of Glasgow, in the County of Lanark,
North Britain, Iron Founder, for the Invention of "IMPROVEMENTS IN
CRANES OR LIFTING AND LOWERING APPARATUS."
PROVISIONAL SPECIFICATION left by the said Alexander Law at the
Office of the Commissioners of. Patents, with his Petition, on the 27th
July 1854.
I, ALEXANDER LAW, of Glasgow, in the County of Lanark, North Britain,
Iron Founder, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN CRANES OR LIFTING AND LOWERING APPARATUS" to be as follows,
namely:-
This Invention relates to a safety contrivance, to be applied to that descrip-
tion of moveable derrick or gib cranes in which the barrel of the, chain for
hoisting the gib is driven, by means of an intermediate pinion in gear with the
spur wheel, on the spindle of the barrel of the main hoisting chain or tackle.
This intermediate pinion is carried on a stud pin, and in ordinary cranes,
when it is necessary to work the main hoist independently of the gib hoist,
the pinion is shifted on its stud out of gear with the spur wheels of the two
barrels, whilst the gib is prevented from falling by a pall, which is turned over
by hand, and made to take into the teeth of the spur wheel on the barrel
spindle.
This arrangement has the defect of requiring two separate operations for
disconnecting the barrels of the two hoists, and accidents frequently occur on
account of neglect or carelessness in adjusting the pall. The object of this
Invention is to render it impossible to set the gib hoist free at any time, by

page_text: arranging so that the action of drawing the intermediate pinion out of gear
with the spur wheel of the main hoisting barrel shall prevent the rotation of
the gib hoisting barrel. One mode of effecting this is by making the spur
wheel of the gib hoisting barrel of such a breadth that the intermediate pinion
will still be in gear with it, although it is entirely out of gear with the spur
wheel of the main boisting spindle; then, to prevent the pinion from turning
whilst out of gear with the driving spur wheel, its boss is formed with a groove
or grooves, to enter upon a feather or feathers formed upon its carrying stud;
or the stud may be made to carry a fixed disc with pins, which enter holes
in the pinion on its being shifted out of gear with the driving spur wheel;
or instead of either of these plans any suitable clutch arrangement may be
adopted.
According to another modification of the Invention, the spur wheel of the
gib hoisting barrel may be made to shift longitudinally upon its spindle, by
means of a groove and feather, and being suitably connected with the pinion,
it will always be in gear with it; whilst a clutch arrangement, similar to any of
those already described, may be applied to either spur wheel or pinion, or to
both. In case the clutch arrangement is applied to the spur wheel alone, the
pinion need not be made to shift.
According to a further modification, the intermediate pinion may be contrived
so as to throw the pall into gear with the spur wheel of the gib hoisting barrel
on being shifted out of gear with the spur wheel of the main hoist.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander Law in the Great Seal Patent Office on the
26th January 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
LAW, of Glasgow, in the County of Lanark, North Britain, Iron Founder,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of July, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Alexander Law, Her special license that I, the said Alexander Law,
my executors, administrators, and assigns, or such others as I, tho said
Alexander Law, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time and at all times thereafter

page_text: 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
CRANES OR LIFTING AND LOWERING APPARATU3," upon the condition (amongst
others) that I, the said Alexander Law, by an instrument in writing under
my hand and seal, should particularly describe and ascertain the nature
of the said Invention, 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 aud immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Alexander Law, do hereby declaro 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 accompanying Drawings, and to the
letters and figures marked thereon, that is to say :-
My said Invention relates to various modifications of safety contrivances to
be applied to that description of moveable derrick or jib cranes in which the
barrel of the chain for hoisting or shifting the jib is driven, in connection with
the barrel of the main hoisting chain or tackle. In one modification of this
class of crane the spindles of the two hoisting barrels carry spur wheels, and
one drives the other by means of an intermediate pinion. This intermediate
pinion is carried on a stud pin in the crane framing, and ordinary cranes are
so arranged, that when it is necessary to work the main hoist independently of
the jib hoist, the pinion is shifted on its stud out of gear with the spur wheels
of the two barrels, whilst the jib is prevented from falling by a pall or
detent, which is turned over by hand, and made to take into the teeth of the
spur wheel on the hoisting barrel spindle. This arrangement has the defect
of requiring two separate operations for disconnecting the barrels of the
two hoisting movements and securing that of the jib hoist, and accidents
frequently occur on account of neglect or carelessness in adjusting the pall.
The object of the present Invention is to render it impossible to set the jib
hoist free at any time, by arranging the details so that the action of drawing
the intermediate pinion out of gear with the spur wheel of the main hoisting
barrel shall prevent the rotation of the jib hoisting barrel. One mode of
effecting this is by making the spur wheel of the jib hoisting barrel of such a
breadth on the face of the teeth that the intermediate pinion will still be in
gear with it, although it is entirely out of gear with the spur wheel of the main
hoisting spindle; then, to prevent the pinion from turning whilst out of gear
with the driving spur wheel, its boss is formed with a groove or grooves, to

page_text: enter upon a feather or feathers formed upon its carrying stud; or the stud
may be made to carry a fixed disc with pins, which enter holes in the pinion
on its being shifted out of gear with the driving spur wheel; or instead of
either of these plans any suitable clutch arrangement may be adopted.
According to another modification of the Invention, the spur wheel of the jib
hoisting barrel may be made to shift longitudinally upon its spindle, by means
of a groove and feather, and being suitably connected with the pinion, it will
always be in gear with it; whilst a clutch arrangement, similar to any of those
already described, may be applied to either spur wheel or pinion, or to both.
In case the clutch arrangement is applied to the spur wheel alone, the pinion
need not be made to shift. According to a further modification, the inter-
mediate pinion may be contrived so as to throw a pall or a mechanical
equivalent into gear with the spur wheel of the jib hoisting barrel, on being
shifted out of gear with the spur wheel of the main hoist. In the arrange-
ment of cranc, in which a spur wheel on the spindle of the jib hoist barrel
gears directly with a spur wheel upon the spindle of the main hoist barrel
without the intervention of au intermediate pinion, the present Invention is
carried out by making the spur wheel on the spindle of the jib hoist barrel
with any kind of clutch arrangement, in such a manner, that when this spur
wheel is shifted on its spindle, upon which it is fitted with a groove and
feather, out of gear with the spur wheel which drives it, the action will bring
it into a position wherein it is prevented from turning by a fixed clutch. Or
instead of this plan, the spur wheel may be carried loosely on the spindle of
the jib hoist barrel, being always in gear with the driving spur wheel, whilst
it is made to turn the spindle of the jib hoist barrel by means of a clutch fitted
on the spindle with a feather, this clutch being arranged to enter a fixed
holding box when it is shifted away from the spur wheel, so that the spindle
cannot turn unless in connection with the spur wheel.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the several explanatory Figures on the Sheet of
Drawings hereunto attached.
Figure 1 on the Sheet of Drawings is a side elevation of a jib crane com-
plete, shewing one mode of applying my safety contrivance; Figure 2 is a
plan, corresponding to the portion of Figure 1 representing the gearing, the
uprights of the frame A being in horizontal section; Figure 3 is a plan of
the gearing, drawn to a larger scale, and representing the intermediate pinion
in horizontal section; Figure 4 is a view of a slightly modified form of clutch
arrangement; Figure 5 is a plan of the gearing, shewing another modification
of clutch arrangement; and Figure 6 is a plan of the gearing of a crane, in

page_text: which the spur wheels on the two barrel spindles gear directly together, shew-
ing one mode of applying the safety contrivance to this class of crane. In the
crane represented in Figures 1, 2, and 3, the frame A is of the usual construc-.
tion, as are also the jib B and the stays C. The general details of the gearing
are also the same as in ordinary cranes. The main hoisting chain D is wound
upon the barrel E, the spindle of which has fixed upon it a large spur wheel F,
in gear with a pinion on a cross shaft G below. This shaft G also carries a
spur wheel H, arranged to be driven by the pinion on the winch handle
shaft I. This shaft I is placed in such a position as to bring its pinion into
gear either with the spur wheel H or with the spur wheel F, accordingly as it
is shifted out or in. thereby varying the power applied. The chain J for
hoisting the jib is wound upon the barrel K, on the spindle of which is fixed
the spur wheel L. This spur wheel L is in gear with a pinion M, carried
upon a stud pin, or upon the overhanging end N of one of the rods, by which
the frame is tied together, which rod projects to form a carrier for this pinion.
This pinion M is arranged so as to gear with the spur wheel F on the spindle
of the main hoist barrel E, and, when in gear, the jib hoist barrel K is driven
by means of this connection, the two barrels being turned simultaneously. In
ordanary cranes of this class the spur wheels F and L are of the same width
on the face, and when it is wished to work the main hoist only, the pinion M
is shifted to the end of its stud pin, so as to be out of gear with both wheels.
When in this position the wheel L is ordinarily prevented from turning by
means of a pall or detent O, carried on a stud pin P, upon the side frame
casting Q. This arrangement, however, as already mentioned, is a very
poor and inefficient preventive against accidents; and, according to one
modification of the present Invention, the requisite security is obtained by.
increasing the width of the spur wheel L, so that the pinion M may always
be in gear with it, notwithstanding that this pinion may be shifted out of gear
with the spur wheel F. Then to prevent the wheels Land M from turning
when the latter is out of gear with the wheel F, the outer end of the stud
pin N is formed with a feather or feathers R, and the eye of the pinion M is
formed with a groove or grooves to correspond; so that this pinion cannot
turn when it is entered upon the feathered portion of the stud pin, and it
consequently keeps the spur wheel L from turning, or allowing the jib to
draw the chain off the barrel and fall. When it is wished to put the spur
wheel L into working gear, the pinion M is shifted inwards upon its stud
pin N, so as to enter into gear with the spur wheel F, and at the same time
become free to turn on its stud pin, from being clear of the retaining
feathers on the outer end of the stud pin. The boss of the pinion M is

page_text: elongated, as at S, and is formed with grooves, in which the hooked end of a
small weighted lever T, carried on a stud pin, is made to lie, to keep the
pinion from shifting otherwise than by hand. Instead of the arrangement
herein-before described in reference to Figure 3, that represented in Figure 4
may be adopted. Here the intermediate pinion M, when shifted out of gear
with the wheel F, is made to come up against a four-pronged clutch U, fixed
on the end of the stud pin N, the prongs of which clutch enter holes in the
dise of the pinion M, and prevent its turning, acting in the same manner as
the feathers R in the former modification. In Figure 5 is represented another
modification of clutch for fixing the intermediate pinion. In this case, the
intermediate pinion M is fixed upon the end of the rod or shaft V, which is
made capable of shifting longitudinally through eyes in the framing A. On
the opposite end of the shaft V, and on the opposite outer side of the crane
framing, is fixed a small pinion W, and when the pinion M is drawn out of
gear with the wheel F, the pinion W is drawn inwards, and enters a box X,
cast upon the outside of the frame casting Y. This box X is formed with
internal teeth, fitting the interstices of the teeth of the pinion W, and pre-
venting this pinion from turning. The pinions W and M, being both fast on
the opposito ends of the shaft V, the latter and the wheel L are of course
prevented from turning when the former is held in the clutch box X. In this
arrangement, the pinion M can be put into and out of gear with the wheel F
from either side of the crane. In Figure 6 is represented one mode of ap-
plying my safety contrivance to a crane in which the intermedinte pinion
between the spur wheels F and L on the barrel spindles is dispensed with, the
two wheels gearing into each other. The spur wheel F, in the special example
here represented, is driven in the same manner as in the arrangement repre-
sented in Figures 1 to 5, with the exception that the spur wheel F. The
spur wheel L is fitted on the spindle of the jib hoist barrel K with a groove
and feather, and it is capable of being shifted on this spindle out of gear
with the spur wheel II is placed on the inner side of the large spur wheel F.
The spur wheel L is formed with an elongated boss Z, on the inner end of
which is fixed or cast a pinion or clutch a; and a corresponding clutch box b
is cast upon the frame casting Q, so that when the spur wheel L is shifted
out of gear with the wheel F, the pinion or clutch a enters the clutch box b,
and is thereby prevented from turning, at the same time keeping the barrel K
from turning, and thereby letting the jib down, by means of the groove and
feather connection between the boss Z and the spindle of the barrel. It will
be obvious that by means of the contrivances herein-before described, these
contrivances being susceptible of modification in various ways, all risk of the

page_text: jib falling is obviated, as at no time can the jib hoist barrel be disengaged
from the details by which it is driven without its becoming connected simul-
taneously with the clutch arrangement by which it is prevented from turning.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried into
effect, I may observe, in conclusion, that I do not confine or restrict myself to
the precise details or arrangements which I have had occasion to describe or
refer to, as many variations may be made therefrom without deviating from
the principles or main features of my Invention; but what I consider to be
novel aud original, and therefore claim as the Invention secured to me by the
bercin-before in part recited Letters Patent, is,-
First, the general arrangement and construction of mechanical contrivances
applicable to moveable derrick or jib cranes in which the jib hoist is worked
in connection with the main hoist, for the purpose of increasing the safety of
the cranes, as herein-before described.
Second, the system or mode of arranging the driving gear of the jib hoist
barrel of moveable derrick or jib cranes, in which the jib hoist is worked, in
connection with the main hoist in such a manner that the action of dis-
engaging the jib hoist barrel from the driving wheel shall clutch it, or prevent
its turning, during such time as it is disconnected from the driving wheel, as
herein-before described.
Third, the system or mode of arranging the gearing of moveable derrick or
jib cranes, in which the jib hoist is driven in connection with the main hoist,
in such a manner that the intermediate pinion, when one is used between the
spur wheels on the two barrel spindles, shall always be in gear with the spur
wheel on the spindle of the jib hoist barrel, as well when the pinion is in gear
as when it is not in gear with the 'spur wheel on the spindle of the main hoist
barrel, whilst the intermediate pinion is provided with a clutch or other
holding detail, to prevent it from turning when not in gear with the spür
wheel on the spindle of the main hoist barrel, as herein-before described.
In witness whereof, I, the said Alexander Law, have hereunto set my
band and seal, this Twenty-fourth day of January, in the year of our
Lord One thousand eight hundred and fifty-five.
ALEXANDER-LAW. (L.S.)