Improvements in and connected with Cranes.
Year: 1899

page_text: Date of Application, 27th Mar., 1899-Accepted, 29th Apr., 1899
COMPLETE SPECIFICATION.
Improvements in and connected with Cranes.
I, JAMES YATE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this Invention (which has been com-
municated to me from abroad by the Wellman Seaver Engineering Company of
New England Building, in the City of Cleveland, in the State of Ohio, United
States of America) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This Invention relates to improvements in and connected with cranes intended
nore especially for use in shipyards, and has for its objects to provide an
extremely stiff and rigid structure for the overhanging cantilever trusses of the
crane; to resist the overturning strains upon the said structure without the necessity
of anchoring the outer ends of the said trusses, and to facilitate the manipulation of
material carried by the crane.
The invention will be clearly understood from the following description with
reference to the accompanying drawings of which—
Figure is a side elevation of a crane supporting structure constructed in
accordance with this Invention;
Figure 2 is a transverse section of the same drawn to a larger scale;
Figure 3 is a side elevation, partly in section, of part of the crane drawn to the
same scale as Figure 2; and
Figure 4 is a plan or top view of part of the crane structure drawn to the sume
scale as Figures 2 and 3.
The crane supporting structure comprises a series of vertical towers, each consisting
of vertical posts 1, 2, connected together by horizontal bruces 3 and diagonal braces 4,
these towers being arranged at any convenient distance apart and as many of them
being employed as the desired length of the structure may require.
The posts 1 of the series of towers are secured together by horizontal longitudinal
braces 5 and diagonal braces 6 the posts 2, being similarly connected and braced
together and the towers are also connected together by horizontal diagonal braces 7,
as shown in Figure 4, thus the towers are rigidly braced both laterally and longitudi-
nally and a strong and stiff longitudinal structure is thus provided.
The tops of the towers carry cantilever trusses 9 which project laterally beyond the
towers to any desired distance and are braced together horizontally, as shown
at 10, in Figure 4 this bracing being in the plane of the bottom chords of the
trusses.
Suspended from the cantilever trusses directly under the bottom chords of the
same, are girders 11 which are provided with tracks on their lower flanges, and on
these tracks run the travelling girders or bridges 12 of the crane. Each bridge has
a trolley traversing the same from end to end and carrying suitable hoisting
mechanism and both the bridges and the trolleys can be actuated by any suitable
power driving mechanism preferably by means of electric motors.
The innermost girders 11 are secured to the posts 1 and 2 of the supporting towers
and form part of the longitudinal bracing of the same.
The girders 11 constitute run-ways extending throughout the entire length of the
•

page_text: crane structure and the bridges 12 can traverse the entire length of these run-ways
thus when the crane is used as part of a ship yard equipment, the hoisting mechanism
mounted upon either crane bridge can be brought over any desired portion of the
length of the ship beneath it without reference to the position of the hoisting
mechanism of the other cranes.
Should it be desired to combine the lifting power
of two cranes the trolleys can be brought together and the lifting tackles be con-
nected, as shown at the left hand side of Figure 2.
In the drawings are shown three girders, constituting two runways, one beyond
the other, laterally on each set of the cantilever trusses, so as to, provide for two
independent crane bridges on each side of the central supporting structure, and this
number may be increased by mounting two, three, or more crane bridges on each pair
of runways or by multiplying the number of runways by increasing the number of
girders depending from the projecting cantilever trusses, or by both of these
methods.
By thus using a number of light-capacity, high-speed cranes, material can be
manipulated with greater facility and convenience than would be possible if a smaller
number of more powerful and slower running cranes were employed.
It is obvious that loads suspended from either of the overhanging cantilever
structures, especially from the outer portions of the same, will set up an overturning
strain which would tend to tip the entire structure over sidewise on account of the
narrow base of the central supporting framework, and, in order to provide for this
strain, the diagonal braces 4 which connect the posts 1 and 2 at the tops of the
towers, as shown in Figure 2, are utilized, strain coming up the top chord of either
cantilever truss being thus transmitted down to the hottom chord of the cross trusses
and cantilevers and thereby resolved into a vertical strain on the posts of the tower,
and as each post is thoroughly braced and stayed by means of diagonal side bracing,
and as the posts are connected together so that the entire series act in unison, it is
impossible to lift up one of the posts without lifting all of the posts in that line, and
sufficient weight is thus provided to counteract any lifting tendency which is likely to
be exerted.
At the bottom of the row of towers is arranged a trolley or runway 13 for
transporting material throughout the length of the structure and there is also a
longitudinal track running along the bases of the towers between the side posts of
the same for a like purpose, and suitable gang-ways 14 and air pipes 15 are
mounted upon the transverse braces 3 connecting the tower posts, while ladders 16
provide means of access between the top and bottom of each tower.
Although the central structure is shown as supporting cantilever trusses projecting
laterally in both directions therefrom, it will be evident that the invention may also
be embodied in a structure consisting of a row of connected towers from which the
cantilever trusses project laterally in but one direction.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
:-
1. A crane supporting structure consisting of a longitudinal row of vertical towers
connected one to another by longitudinal bracing, and each supporting a laterally
projecting cantilever truss, whereby the uplifting strain upon the posts of any one
tower is transmitted to adjoining towers, substantially as hereinbefore described.
2. A crane supporting structure consisting of a longitudinal row of vertical towers
connected by longitudinal bracing and each supporting a laterally projecting cantilever
truss, the said trusses being likewise connected by longitudinal bracing, substantially
as herein before described.
3. A crane supporting structure consisting of a longitudinal row of vertical towers
connected together by longitudinal bracing and each supporting a pair of cantilever
trusses projecting laterally therefrom, one in one direction and the other in the
opposite direction, the said cantilever trusses being likewise connected by longitudinal
bracing, substantially as herein before described.

page_text: 4. A crane consisting of a longitudinal structure with cantilever trusses projecting
from one or both sides of the same, the said cantilever trusses carrying longi-
tudinal girders forming runways one laterally beyond another for the reception of
travelling crane bridges, substantially as herein before described.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.