IMPROVEMENTS IN DREDGING MACHINERY
Year: 1883

page_text: "
LETTERS PATENT to William Edward Gedge, of N° 11 Wellington Street,
Strand, London, in the County of Middlesex, Patent Agent, for an Invention
of "IMPROVEMENTS IN DREDGING MACHINERY" a communication to him
from abroad by Horace Bucklan Angell, of the City and County of San
Francisco and State of California one of the United States of America,
Gentleman.
COMPLETE SPECIFICATION filed by the said William Edward Gedge at the
Office of the Commissioners of Patents on the 17th November 1883.
WILLIAM EDWARD GEDGE, of N° 11 Wellington Street, Strand, London, in the
County of Middlesex, Patent Agent, "IMPROVEMENTS IN DREDGING MACHINERY"
a Communication to me from abroad by Horace Bucklan Angell, of the City and
County of San Francisco, and State of California, one of the United States of
America, Gentleman,
This Invention relates to certain improvements in dredging machines, of that
class in which a series of buckets are secured upon an endless chain, which
together with an inclined ladder over which the chain of buckets is moved, is
supported upon a boat or scow, so as to be advanced as the work progresses.
This invention consists of certain improvements in the construction of the chain,
and buckets, the ladder, the tumblers at each end over which the chain passes, a
means for suspending the ladder, and also the pipe which conveys away the
material received by it from the buckets.
It further consists of a means for advancing the scow as the work progresses,
and in certain details of construction, all of which will be more fully explained by.
reference to the accompanying drawings, in which :-
Figure 1. is a side view of the machine.
Figure 2 is an end view of the same.
Figures 3.4 and 5-are views of the chain links and buckets, and the tumblers
around which they pass.
Figures 6 and 7-are views of the hopper into which the buckets discharge, and
part of the conducting pipe, also the independent support
for the upper end of the ladder.
}

page_text: Figures 8 to 16 inclusive, show the construction of the ladder, the turning
joint of the hopper, etc.
Figure 17-is a front elevation of the gearing apparatus
Figure 18-is an enlarged view showing one of the drums in vertical section;
the rest of the parts in elevation.
Figure 19-is a view showing the brake.
Figure 20 is a plan showing the means for advancing and holding the scow as
the work progresses.
A, represents a boat, having, as shown in Fig: 2, a longitudinal channel in its
center. B, represents the engine or other power, driving by a belt, the parts with
which it is connected upon top of the vertical frame or support D
I have here shown certain arrangement of pulleys and power mechanism which
needs no explanation, as it is accomplished in the usual manner.
E, represents timbers in top of the vertical frame D.
F, represents the ladder with its side frame-timbers jointed at c¹.
My first improvement has relation to the end connections of these ladder frame-
timbers F
G, is a horizontal shaft, having pulleys, as shown, and journaled in pillow blocks
or boxes u upon timbers E, Figs: 8, 9, 10.
H, represents the fastening-irons or nose pieces on the upper and lower ends of
the ladder-timbers.
Those above fit over the sleeves t, which receive the shaft G, as shown, the said
Shaft being supported by the pillow blocks or boxes u, and is smaller than the
sleeves, so as not to touch their sides-The shaft is thus relieved from any
weight or strain, the whole being supported by the boxes u on the frame-timbers.
The upper nose-pieces H, are secured by bolts about said sleeves, and are
made in two longitudinal sections for convenience in fitting said sleeve and the
timbers F.
-
Thus the shaft G, is allowed to revolve without interference
These nose-pieces have, as shown, each an extended socket a, having three
inclosing sides, into which the ends of the ladder-timbers fit, and are bolted therein
securely
These nose-pieces below are made of a single piece and fit over the shaft of the
lower tumbler in an ordinary journal, allowing the revolution, of the said shaft, and
are securely bolted to the lower ends of the ladder-timbers F
This method of securing the ladder-timbers gives strength to the ladder
In the ordinary dredgers of this kind the ladder F, is supported by trusses, and
its inclination varied by power applied to its lower end. As the ladder with all
its parts is very heavy this plan is not a good one.
My improvement in this respect is as follows:-Pivoted to the sides of the
ladder-timbers F, are the bails K, extending in front of the ladder, and having
attached to them the vertical pulley L.
N, represents appropriate frame work or supports carrying pulleys b.
O, represents a gypsy or windlass upon the boat
M, is the chain, one end of which is attached to the upper bail K, and passing
over the stationary pulleys b, and the movable one L, over a pulley, c, in the
vertical frame-work D-down to the windlass O, fig 1.
By this means an increase of power is obtained, and it is applied evenly upon
the ladder to change its inclination when necessary
I have shown the tumbler I, around which the bucket chain d, passes, journaled
in boxes e upon the upper top timbers E.
Below these are other timbers, F¹, supporting boxes G, in which the trunnions
of the upper section of the ladder F, turn independently of the tumbler and its
journals.
These boxes are so placed with relation to the upper ones that the chain will
load from the laddar
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the tumbler and thence down beneath the ladder

page_text: again in an easy natural curve, and, by being thus separated, each may be repaired
without disturbing the others.
The tumbler is composed of ends or heads f, cast or formed with recesses at
each angle into which the ends of the transverse angular beams g are let, and
these beams. are cored longitudinally, so that the rods h may pass through them.
These rods have heads on one end and nuts upon the other, or nuts upon both
ends, by which they are drawn up and the whole held firmly together.
Whenever either of these angle-pieces g becomes worn it may be easily removed
and another inserted.
Let D represent the series of connected links forming the endless chains
passing over the tumblers, Figs: 3 and 4. C are the bolts or pivots securing the
links together.
Every alternate link is of a single piece, every other one of two pieces, as shown
in Figs: 15 and 16.
Q, represents the buckets, of a shape flaring toward the mouth, the upper lip
being cut away to allow the lower one to project for the purpose of throwing the
mud directly within the hopper, as shown hereinafter.
These buckets are longer than one link in the endless chain d, and are wider
than the said chains, so that when set thereon they extend over the length of the
single link and cover a portion of the double links in front and behind, as shown
in Fig: 3.
This protects the joints of the links in passing over the tumblers. The sides
of these buckets project over both sides of the chain d, as shown in Fig: 2. This
protects the tumblers, because the buckets are high enough to pass over the edges
of the said tumblers, and prevents any undue strain upon the lower tumbler by
forcing it against the bank.
Within the buckets Q, are the braces w bolted through flanges on their ends to
the upper and lower walls. They consist of a strong metal bar, and serve to
prevent the bucket from bulging.
In order to facilitate and support the chain d in passing over the ladder, I place
rollers a Fig 13, journaled to the ladder-timbers F, and allow the chain to rest
upon them, and thus be rolled forward
To the inner sides of the single links of the chains d, are bolted the strips of
angle iron R, the upper sides of which extend inwardly as shown.
The buckets Q are bolted down to these angle iron strips, which form a stable
and firm support, and do not interfere with the turning of the links.
Letter I, represents the tumblers, the one above keyed to the shaft G¹ and the
one below loose upon a shaft journaled in the nose-pieces of the ladder-timbers,
both being of ordinary form, as shown, having their ends f, and flanges for
receiving the chains.
I may have the lower tumbler five-sided, if desirable. The chains d in
passing around said tumblers are apt to strike and rub their joint bolts d¹ against
the ends f
To obviate this and protect both tumblers and joints, I have beveled or cut
away the sharp corners and edges of said ends f, as shown at g¹ in Fig: 4.
Letter S, represents the spout or discharge pipe. This pipe extends out toward
the bank to any desired distance
It has an elbow P, on its inner end, as shown, and is provided with the hopper U
placed in position to receive the contents of the elevating buckets as they pass over
the upper tumbler, I,
The edge or lip of this hopper toward the approaching buckets is cut away
lower than the surrounding edge, Figure 7
This is for the purpose of better receiving the projecting under lip of said
buckets and insuring their discharge directly within the hopper without spilling
any of their contents.
In order to advance the scow or barge upon which the machinery is carried, and
swing it from side to side as the work progresses, I employ a spud, K¹, which is

page_text: put down in a central fore-and-aft line of the scow, and behind a central transverse
line.
Another spud, L¹, is placed at one-side of K¹, at right angles from the
central line, the two being separated such a distance that when the spud L¹ is
dropped and the scow swung to one side it will advance for a new cut.
While a cut is being made the scow is caused to swing slowly from side to side
of the proposed channel, the spud K¹ being dropped so that it forms the centre
about which the cut is made, and the spud L³ is raised.
As the scow swings the buckets make the cut, working down gradually until
the bottom is reached when it is ready to be advanced for a new cut. While the
ladder is at the opposite side of the channel from the spud L, and is being raised,
this spud is dropped and the spud K³, withdrawn, after which the scow is made
to swing about the side spud, L¹, as a center until the spud K¹ has been
advanced to its new position, when it is again dropped and the spud L'
withdrawn.
.
The machine is thus held in position at all times by one spud, and is
prevented from being driven out of position by the wind or tide, and the
advance of the working-spud K¹, is made in the central line of the channel to
be cut.
In order to move the scow easily about its center, I employ two anchors i and j
upon the shore opposite the front of the ladder.
Blocks k are fixed to the sides of the ladder and ropes or chains 7 lead from the
anchors through these blocks and thence back to the gipsies or drums T, around
which the coil or uncoil and by which the scow is caused to swing from side to
side.
The strain is greatly lessened by placing the pulleys or blocks k so far forward.
and upon the bucket carrying ladder, as the buckets must cut from their sides
when the apparatus swings from side to side.
To still further assist in this action and reduce the strain, other lines or chains m,
pass around drums n, and thence around pulleys at the rear of the scow, and from
these to anchors X, upon the bank as shown..
When one of the forward lines is wound up, the line m leading from the rear.
to the opposite bank is also wound up, so that both front and rear of the scow
are moved around the spud or fulcrum which is situated between them, and the.
power needed as well as the strain greatly lessened. The opposite lines and m
will of course be slacked off at the same time.
When the buckets are bringing up soft mud there is no difficulty in discharging
it, but if it is hard clay or sand it will be apt to stick in the buckets so that they
will carry some of it back upon their return.
In order to prevent this, I fix a nozzle Y, upon the side of the receiving-hopper
opposite to the point where the buckets pass over the tumbler, and in such a
position that it will discharge a stream of water directly into the top and back
portion of the bucket as it comes up over the tumbler, and this loosens the material
and moistens it so that it will drop out freely.
I make the side V, of the hopper, at a considerable incline, and the curve W,
which joins this incline with the discharge-pipe, is more in the form of a parabolic
curve, so that when the mud from the bucket falls upon the incline V, it glides
down and is directed by the curve W, into the discharge pipe S, and the momentum
thus gained is sufficient to prevent any clogging at the angle and to cause the mud
to shoot out through the pipe with great velocity
I prefer to place the piny which supports the hopper and turns in a step, as
described, in such a position that the falling material will strike directly above it,
so that it will receive the force of the blow, and thereby materially strengthen
the wall of the hopper. In order to obtain the requisite length of ladder and
still relieve the chains of some of the weight, I have found it preferable to
make the ladder in two portions and connect them with a joint or hinge. This
c.

page_text: improvement I have shown in Figs: 13. The side timbers, F, are jointed or
hinged at about or below their middle, as shown at c¹.
J
The upper portion of the ladder is supported by a separate set of chains and
pulleys from those which support the lower, thus allowing the lower part to be
raised or lowered, as required, without moving the entire ladder. The upper
part may be supported entirely by its chains or by a cross beam on the
frame-work.
:
'
Thus the upper portion may remain steady and the lower part be. made to
accomodate itself to various inclinations.
The chain which is illustrated in these drawings is formed, in the usual way, of
alternate single links and double links.
The eye 1 of the single link is inserted between the eyes 2, 2, of the double
link, so that the openings register, and through these openings is passed the pin C,
which is composed preferably of hard steel. .
The pin C, has a head, d of greater diameter than that of the eye, and is of
sufficient length to extend a short distance beyond the link on the opposite side,
and to be bored out transversely to receive a pin 3, which holds it in place and
prevents it from being withdrawn.
A washer, 4, is preferably placed on the pin, so as to bear against the outside
surface of the link, as shown in Fig: 15.
In order to relieve the steel pin from all wear, I interpose between such pin and
the moving surface of the links tubular sleeves or bushings d. Each of these
bushings is just of sufficient length to fit the bearing surface of the eye to which
they are applied, and when placed upon the pin they exactly fill the space between
the head of the pin and the washer, the joints between them exactly registering
with the joints of the link.
They are therefore free to move independently on the pin and with the link
against which they bear, and it will be evident that all the wear is upon the
bushings, the steel pin being entirely protected. I prefer to make my bushings of
either gun-metal or phosphor-bronze.
These metals, while soft as compared with hard steel, nevertheless possess great
toughness and tenacity, which adapts them particularly for use in bearings, and
while their wearing qualities are greater than those of steel, they can also be
replaced, when necessary, at much less expense.
1
It is evident that in chains of this class the wear is entirely in the direction of
the length of the chain, so that the bushings will wear constantly in one place.
The described bushings, therefore are capable of being adjusted by removing the
pin and bushings, and inserting them in different positions in the links, so as to
present a new bearing surface.
This can be done repeatedly, or until the bushing is entirely worn out, when
new ones can be inserted at slight expense.
'
It may be. stated, as showing the advantage obtained by the use of soft metal
for this purpose, that the hard steel bushing exposed to ordinary wear in a dredger
chain will only last ten days, while a gun metal or phosphor bronze bushing
similarly used has remained in use for four months.
As the double links, pull in an opposite direction from the single links, the
wear is on opposite sides of the respective bushings, and they are therefore made
of independent sections, as described, since a single cylinder would be pulled or
twisted out of shape by the strain.
In order to control the movements of the boat from side to side, a shaft extends
across the scow having pinions o fixed to it at suitable or convenient points.
These pinions engage and drive the gear wheels p which are fixed to the drum
shafts q
The rope drums n turn loosely upon these shafts, and a friction wheel n¹ is
secured to the shaft, near one end. of each drum, which is formed to engage with
the friction wheel and be turned by it when desired.

page_text: The drum is held away from the friction wheel by springs r, and is forced into
contact with it when it is to. be rotated, by a lever 8.
This lever is connected by a rod s¹ with a lever
latter lever extends to a point within easy reach of the operator.
upon the bridge, and this
The ropes or chains m which are anchored to the bank, pass through snatch or
leading blocks and are led to the drums n to which they are permanently
secured, instead of passing around gypsies and being taken off as they are
drawn in.
By this mechanism it will be seen that as the ropes are permanently attached to
the drums, they may be wound upon them by simply throwing the drums and
friction wheels into contact, and when this is done upon one side in order to swing
the scow to that side, the other drum is allowed to turn freely, and the rope will
thus unwind from that drum as it winds upon the other, the whole being controlled
from the bridge or other desired point.
A brake v, is fixed to act upon the drum, with a constant friction to prevent the
rope from unwinding too rapidly and becoming fouled when the drum is running
free, but the pressure is not sufficient to materially retard it.
I have shown two masts Z, having their lower ends stepped upon the bottom
timbers of the scow or on deck, at some 'distance apart.
Their upper ends approach each other and also incline outwards beyond the side
of the sców, the discharge pipe S extending out between them.
From their upper ends a single top mast 2 extends upward, its foot being
strongly secured between them, so that it forms an extension of the lower masts.
From the top of the mast and at intervals downward strong wire rope guys Q¹
extend back to the frame work of the dredge, and thus support it.
Other guy ropes R¹, extend from this derrick mast to points along the pipe where
they are secured to bands T, and thus support the pipe at intervals.
The guys Q¹ and R¹, form a continuous support from, the pipe to the dredger
frame, by means of the bands 7%, which surround the mast and have eyes for the
attachment of two or more of the guys upon either side, so that the mast serves as
a guide to give direction to the guys, but is relieved from any direct pulling strain,
due to the weight of the pipe.
Having now described and ascertained the nature of the said Invention Communi-
cated to me as aforesaid and in what manner the same is or may be performed
what:-
I Claim as new, and desire to secure by Letters Patent, is :-
1. The ladder or chains supporting timbers having nose or end pieces, with
sockets to receive the timber ends, tumblers consisting of removable end pieces with
connecting bars and rods, and supporting sleeves and shafts for the tumblers, the
ladder timbers being also jointed so that the lower end may move independent of
the upper end, said upper ends being journaled in supports independent of the
tumbler supports, and suspending bails and mechanism by which the ladder or
either of its sections may be raised or lowered as herein described.
2nd The bucket carrying chain of a dredger composed of single and double links
with independent tubular sectional bushings in the link ends, buckets of greater
length than the links to which they are attached, and greater width than the space
occupied by the chain, and having the upper forward lip cut away, and the under
lip projecting with interior braces for the buckets, as herein described.
3rd A receiving hopper into which the buckets upon the dredger chain discharge,
and a water pipe or means for cleansing the buckets as they discharge; a conveying
pipe connected with the hopper by an elbow or curved section, supported upon a
pivot pin and having a swivel joint between it and the hopper, wheels running
upon a curved track and supporting the inner end of the pipe; and masts with
guy ropes extending to the frame and also to the pipe to support it where it
extends away from the side of the vessel or scow.
4th A means for advancing the vessel or scow, consisting of a central post or
spud, about which it swings, a secondary post passing down at a short distance to
E

page_text: one side of the first, and means for raising them alternately as the vessel swings
to one side or the other; ropes anchored to the banks upon each side and passing
through leading blocks upon the vessel to winding drums with friction gear, and
connecting levers, as described.
In witness whereof I the said William Edward Gedge have hereunto set my
hand and seal this Sixteenth day of November in the year of our Lord One
thousand eight hundred and Eighty three
WE GEDGE (LS.)