Pontoon Transfer Bridges for Dikes and Canals.
Year: 1897

page_text: Date of Application, 6th Apr., 1897-Accepted, 3rd July, 1897
COMPLETE SPECIFICATION.
Pontoon Transfer Bridges for Dikes and Canals.
We, ALEXANDER MCKAY WYLIE, Engineer and LOUIS COHEN, Merchant, both
residing at No. 113 Russ Street, in the City and County of San Francisco, State of
California, U.S.A., do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
Our invention relates to the general class of apparatus used in dredging canals
and other excavations, and the forming in connection therewith of dikes and
embankments bordering said work.
Our invention consists in a novel apparatus to be used in connection with the
dredging machine, and which we call a pontoon transfer bridge.
The object of this apparatus is to follow up and act in conjunction with the
dredging machines, to receive the dredged material therefrom, and automatically
transport it to and over and beyond the dike or embankment. In the work of
making or dredging such water-courses as above mentioned, it is common for the
dredgers to advance along the work and deposit the dredged material upon the
borders to form the dikes or embankments. In the use of our device it is intended
that one dredger shall proceed close to the border and shall throw up the dike or
embankment. by its own discharge mechanism and upon the grade desired. Following
this dredger shall be another dredger, but out of line with the course of the first,
that is to say, farther out in the line of the work, and as said second dredger may be
too far to deposit its dredged inaterial beyond the bank made by the first, we intend
that our apparatus shall operate in conjunction with this second dredger, and in a
line nearer the bank, so that it shall receive the material from said second dredger
and automatically transport it over and beyond the bank or dike made by the first
dredger. And in case more dredgers are used, our apparatus will be used with each
succeeding one, and will be used with dredgers operating on the other bank.
Our invention consists in a suitable pontoon or float having upon it a receiving
hopper or hoppers adapted to receive the material directly from the dredger dipper of
the dredger alongside; a bridge or bridges connected with said pontoon or float and
extending therefrom to and resting upon the bank previously made and projecting
beyond said bank; a car or cars adapted to receive the material directly from the
hoppers and to pass over said bridge or bridges to their inner ends; means for
causing the travel of said cars back and forth; means for automatically dumping
them at the inner ends of the bridges whereby they deliver their loads beyond the
dike or embankment, means for connecting the bridges with the pontoon or float by
adjustable connections to provide and compensate for all the necessary movements
of the pontoon without affecting the position of the bridges or straining them; means
in furtherance of this object by which the bridges rest upon the bank and have their
necessary adjustable movement, and other details of construction, arrangement and
combination which we shall hereinafter fully describe by reference to the
accompanying drawings, in which—
Figure 1 is a side view of our pontoon transfer bridge.

page_text: Figure 3 is a section of the turn-table.
Figure 4 is a detail view of the adjustable support for the bridge on the bank.
Figure 5 is a side view of the automatic car discharging mechanism.
Figure 6 is an end view of the same.
Figure 7 is a bottom view of the car shewing the spring adjusted front axle.
A represents a pontoon or float of any suitable character and provided with all the
necessary means for controlling it.
Upon this float is a hopper B or a plurality of hoppers, and for the sake of
illustration two hoppers are here shewn.
Upon the float is also a suitable tower C for the operator, said tower being high
enough to enable him to see down into the hoppers, and over them so that he can
see the dredger working beyond, and he can also see the whole of his apparatus, and
can thereby observe the proper working of all the parts.
The surface of the float is made with a slope to one side in order to provide for the
necessary cleansing, by washing, of its deck.
Extending from this float is a bridge D, or there may be as here shewn, a plurality
of bridges, two being illustrated for the sake of this description. These bridges
extend to and rest upon the embankment E which has been previously made along
the border of the work, and their inner ends are long enough to project beyond said
embankment.
The bridges are of any suitable and approved construction to combine lightness
with strength.
F are cars which are adapted to pass under the hoppers and to receive the
material from said hoppers, directly from the dipper of the dredger, so that said
hoppers simply act as funnels to enable the dipper of the dredger to direct its load
into the cars, and said cars have capacity enough to take a full dipper load. When the
cars are in a position to receive a load from the hoppers, their axles are supported by
blocks, to prevent their being broken by the impact of the falling load.
These cars travel upon track rails G on the pontoon, and on the bridges and they
are adapted to be moved to and fro by means of any suitable driving mechanism,
which we have herein indicated as a cable g attached at both ends to the car axles,
one cable to each car, and said cable thence extends around suitable terminal
sheaves g¹ on the pontoon, and at the inner ends of the bridges, and it is driven by
means of suitable driving mechanism as indicated at g² within the pontoon.
This driving mechanism may be supposed to be and is directly under the control
of the operator in the tower by means of suitable and ordinary connections,
unnecessary herein to show, as it will be readily understood from what has been
described, that the cars may be propelled from under the hoppers, over the pontoon,
and over the bridges to the inner ends thereof, and then be pulled back again.
Now in order to automatically dump the cars at the inner ends of the bridges, we
have the following construction:
Secured to the inner ends of the bridges are placed guide rails H, one above and one
below and connected by suitable ties h.
These guide rails have downwardly curved extensions h¹ projecting beyond the
bridge ends.
There is a pair of these guide rails on the inner side of each side of each bridge,
so that for each bridge there are two pairs of these guide rails and they are disposed
in vertical planes, and lie in alignment with the track rails G on which the
cars run.
When the cars reach these guide rails H, the wheels of the cars travel between
the upper and lower guide rails, and the forward wheels of the cars travel down the
curved extensions h₁ of the guide rails thereby inclining the cars downwardly, and
throwing them into position to discharge their loads by gravity, and said loads are
discharged beyond the bank E previously formed. Now, in order to prevent the cars
from descending to this inclined position with too great force, as they are very heavy,
we have on the inner side of each side of each bridge a pneumatic compression
cylinder I, either vertical or horizontal, the piston rods i of which are connected to a

page_text: cross bar by a chain or rope from which bar projects upwardly a central arm i².
The cross bar connected to the pneumatic piston-rods has its ends provided with
anti-friction rollers 23 which travel in side grooves g³ in the rail stringers g* so that
great accuracy of movement is attained.
On the rear axle of the car, we have attached a downwardly projecting bail f which
is adapted to come in contact with the arm 2 and to thereby, as the car advances
pull out the piston-rods of the pneumatic cylinders, which latter thus serve to check
the car and hold it from descending with too great force.
On the return movement of the car, the bail fƒ of its rear axle simply leaves the
arm and the pneumatic devices return to initial position for a repetition of the
operation with the car, when it again approaches it.
The front axle f¹ of the car is adapted to have a sufficiently free movement in
bearings under the car body to enable it to turn slightly to adjust itself to the
necessary courses of travel, and said axle is held to its adjustment by means of a
spring f acting upon it.
In order to hold the material in the cars until it is ready to be dumped, we provide
an end gate K for each car which is hinged to the end of said car above by suitable
connections as shewn at k, and said gate lies at an incline with the end of the car in
order to adapt it to close by gravity.
Pivoted latches are attached to the gate, working in suitable guides k² and
adapted to engage with catches on the end of the car body.
These latches project beyond the sides of the car and are adapted to run out upon
and in contact with straight bars 4 which begin just about the curved portion h³ of
the guide rails H.
Now when the car reaches this curved portion, the ends of these latches k¹
travelling out on the straight bars 4, and the car itself following the curve h¹ of the
guide rails H, said latches are raised from their catches ³, and when the car tilts,
the weight of the material within it will open the now freed gate K and the contents
will be discharged.
As the car returns and the latches are freed of the straight bars, the gate will
swing closed by gravity, and the latches return to their engagement with the
catches, thus providing for a complete automatic operation for the dumping and
discharging of the cars.
It is necessary that adjustable connections be provided between the bridges and the
pontoon to permit the movements of the latter as it lies in the water and without
communicating any strain to the bridges.
These connections and devices are as follows:
On the pontoon and in the line of rails G of the cars are turn-tables L having at
their forward ends, one on each side, hinge connections M with adjacent ends of the
bridges, so that the pontoon and the bridges are thereby connected in such a way as
to permit a relative independent vertical movement, and by reason of the turn-tables
a relative horizontal movement is also permitted, so that the pontoon may rise and
fall and may swing or move horizontally in any direction without affecting the
bridges.
The rails G on which the cars travel must cross the turn-tables, and for this
purpose and not to interfere with the necessary movement of the tables, the rails are
first severed at g5 in the line of the hinges M, and the rails which lie upon the
turn-table are curved or frogged outwardly at their inner ends as seen at 9º.
The rails which lie upon the solid portion of the float or pontoon overlap the inner
edge of the turn-table and are free thereof, and the ends of said rails are curved
or frogged outwardly as shewn at g'.
These two curved adjacent ends of the rails provide for guiding the car wheels to
and from the turn-table with accuracy within the limited arc of movement to which
the turn-table is subjected, for the wheels will cross between the intervening space
by running on the turn-tables by their flanges, until they strike the rails again
which by reason of their curves, or what may be termed their frogs, will again engage
the flanges and direct the wheels properly.

page_text: The bridges do not lie solidly upon the bank but upon movable connections
which are necessary to provide for the relative independent movements heretofore
described.
N is a temporary track laid upon the bank E and upon this is adapted to travel
wheeled trucks 0, one for each bridge, said trucks having longitudinally disposed 5
upon them, centrally pivoted or swinging saddle-blocks P upon which the bridges
rest. Now as the connected ends of the bridges swing with the float or pontoon,
their bearing ends move back and forth with the trucks and swing with the pivoted
saddle-blocks so that the relative movements of the pontoon and bridges are such
that each may take place with perfect independence, and no strain be communicated 1
to the bridges.
The operation of the apparatus briefly described is as follows:
As before stated, a preceding dredger may be supposed to have thrown up the dike
or embankment E, and a succeeding dredger may be supposed to be following the
first, but in a different line. Our apparatus is to be located between this second 1
dredger and the bank, and said second dredger deposits its material from the
dipper directly into the hoppers on our pontoon, making a deposit alternately in each
hopper.
The operator in charge of our apparatus has one of his cars always under the
hopper at the time the dipper delivers its 'oad, and consequently, said car is loaded 2
directly from the dipper. He then runs said car out over its bridge, and the car is
automatically dumped of its load beyond the embankment, and then returns for
another load, and while this is being donc, the second car has been loaded and is
being run out and, in due time, it also is returned.
Our apparatus may be duplicated in its parts as necessity requires, and may be 2
extended or as many separate ones may be used as may be desired.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what we
claim is :
1st. A pontoon transfer bridge for dikes and canals consisting of a suitable float or a
pontoon having a hopper to receive the material from the dredger, a bridge
connected with said float or pontoon, and thence extending to and over the bank, a
car adapted to receive the material from the hopper and means for effecting the
travel of said car from the float or pontoon over the bridge, the fixed guide rails with
downwardly curved extensions at the inner or land end of the bridge and by which a
the car is turned downwardly, the means for automatically closing and opening the
car when turned downwardly, consisting of the swinging gate closing by gravity, the
latches, and the catches with which they engage, and the fixed straight bars engaging
the latches to automatically open them, and the means for controlling the descent
of the car consisting of the pneumatic compression cylinders with their piston-rods
and sliding cross-head having a contact arm, and the bail on the rear axle of the car
engaging with said contact arm.
2nd. In a pontoon transfer bridge for dikes and canals, the combination of a float
or pontoon, a bridge extending therefrom and capable of movement in a vertical
plane, a turn-table, track rails on the pontoon or float and bridge, the rails on the
former overlapping and independent of the turn-table, a hopper on the float, a
vehicle to travel on said rails and to pass under the hopper and a means for operating
the vehicle to and fro upon the rails.
3rd. In a pontoon transfer bridge for dikes and canals, the combination of a suitable
float or pontoon, a bridge extending from the float or pontoon to and over the bank,
adjustable connections between the bridge and the float or pontoon whereby the
motions of the latter are permitted without affecting the bridge, consisting of a
hinge-permitting movement in the vertical plane, and a turn-table permitting
movements in horizontal planes, and movable devices on the bank and upon which
the bridge rests, said devices consisting of a movable truck and a longitudinally

page_text: disposed centrally pivoted saddle-block on said truck and upon which the bridge
rests.
4th. In a pontoon transfer bridge for dikes and canals, the combination of a
suitable pontoon or float, a bridge hinged thereto and thence extending to and over
the bank, a turn-table on the pontoon or float and to which the bridge is connected,
rails upon said pontoon or float and bridge, the rails on the former overlapping and
independent of the turn-table and outwardly flaring,-rails upon said turn-table in line
with the rails on the bridge and having their ends adjacent to the rails on the
pontoon outwardly curved or flared, and cars adapted to travel over said rails, said
cars having adjustable forward axles with controlling springs.
Dated this Sixth day of April, 1897.
For the Applicants,
GEDGE & FEENY,
60, Queen Victoria Street, London, E.C., Chartered Patent Agents.