IMPROVEMENTS IN DREDGING MACHINES
Year: 1884

page_text: I EPHRAIEM CHAQUETTE, of N° 715 Hayes Street in the City and County of
San Francisco, in the State of California, one of the United States of America,
Gentleman, do hereby declare the nature of my invention for IMPROVEMENTS IN
DREDGING MACHINES and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
My invention relates to certain novel construction of parts devices and apparatus
in and of machines for carrying on dredging and excavating operations; and also
to the production of a dredging machine possessing many advantages in respect to
simplicity of mechanism and the capacity of cutting and raising a large body of
material in a given time and under different situations.
These improvements pertain more particularly to dredging machines of that class
in which a rotating excavator or cutting and dredging implement and a suction
pump connected together by a suction pipe are mounted on a scow or barge with
the necessary power and mechanism for handling and submerging the excavator
and moving it under the water, and for rotating the excavator and driving the
pump.
The first part or feature of my said improvements relates to a novel construction
of scow or barge for dredging purposes, and the same consists in making a portion
of the scow capable of immersion independently of and to a greater depth than
the principal part of the structure so that the dredging apparatus being mounted
upon this independently movable section it can be raised and depressed to adjust
and accommodate the cutting and dredging machinery to the varying conditions of
work. It also relates to a novel construction of crane or swinging frame for
carrying applying and operating a rotating cutting or dredging tool from a scow or
carrying platform, the same consisting in the combination of a horizontally
swinging crane having movement on a fixed center, and a vertically moving beam
or frame hinged at the inner end to this swinging crane and suspended from the
boom of the crane at the outer end by a block tackle so as to be raised and lowered
and fixed at any desired point of elevation or depression to hold the excavating
implement on its outer end to the work to be done. It also relates to an automatic
indicator for showing the position of the excavator when submerged so that the
depth at which it is working and any change of position is always exhibited and
made known to the workmen on the scow; and the same consists of a scale of

page_text: vertical distances fixed on the mast or vertical frame of the crane, and a moving
index connected through a series of levers with the vertically movable beam that
carries the excavator, the proportions of these parts being such that the vertical
distance traversed by the outer end of the beam from the horizontal or at the
water-line down to the lowest position of submergence of the excavator, and all
intermediate points between, will be indicated by the pointer or index the divisions
upon the scale being calculated to feet and fractional parts if desired. It also
relates to a novel means of driving spud or pile anchors, and for extracting and
raising them out of the bottom in which they are driven.
The second part of my invention relates to improvements in the excavator, or
cutting and dredging implement; and the same consists in providing more than
one suction chamber in the drum or stationary part of the excavator, and making
separate or independent attachment of the suction-pipe with each chamber; also in
applying blades or cutters to the outer case or revolving cutting part of the
implement in front of the buckets or scoops on its periphery, and in fixing said
blades in such manner that they can be taken off for adjustment and repairs.
It also relates to a novel construction of extensible connecting-rod or shaft for
connecting the rotating excavator with its power shaft, by which such connection
is obtained and the implement propelled under all conditions of change in position
of the vertically moving beam.
The third part of my invention relates to improvements in the suction pump or
centrifugal pump; and the same consists in certain novel construction of outer
stationary case or shell in two parts, in the application of removable wearing
surfaces therein, in the joints and bearings and the means for keeping them free of
sand and grit, and in the construction of the revolving chambered block and the
spiral passages therein.
The fourth part of my invention relates to improvements in the suction pipe for
connecting the excavator at the end of the swinging beam with the suction-pump
on the scow, and in certain novel construction of flexible joint or connection
therefor.
These parts and features, their combination and application together and with
the necessary machinery and power are clearly shown in the several views of the
accompanying drawings in four sheets; referring to which-
Figure 1, represents in elevation the front or forward end of the scow or barge,
with the parts and mechanism in position for work but with the excavator raised
up clear of the bottom. The stern or rear end of the scow is broken off and the
side of the bull at the movable tank-section is removed to expose the suction
pump.
Figure 2 is a plan or top view with the roof or upper works of the scow
taken off.
Figure 3. is a detail view on a larger scale of the mechanism for rotating the
excavator and for moving the swinging beam of the crane on its center from side
to side.
.
Figures 4, 5, 6, 7, 8, 9 and 10 are views in general and in detail of the suction-
pump, of which figure 4 is a side elevation, figure 5 a longitudinal section through
the shell or case the revolving chambered block being shown in full form and the
section confined only to the case, figure 6 the principal parts detached and separated
to show more clearly the construction of the revolving block and the manner of
keeping the joints and wearing surfaces clear of sand and grit by means of water-
jets, and the remaining figures, the parts of the spirally chambered block in detail.
Figures 11 and 12 give the details of the swinging crane, the suction pipe by
which connection of excavator on the craue is made with the pump on the scow
and the indicating mechanism for showing the depth at which the outer end of the
beam is submerged when at work.
Figures 13 to 19 inclusive relate to the revolving excavator-figure 13 being a
general outside view, figure 14 an end view from the bar where connection of the
suction-pipe is made, figure 15 a longitudinal section, figure 16 a view of the inner

page_text: stationary shell or chambered block, figure 17 a longitudinal section through this
part, figure 18 the outer end of the suction pipe and figure 19 the detachable
guards and cutters in detail.
Figures 20 and 21 are detail views in elevation and plan of the movable tank
section in the scow.
Figures 22, 23 and 24 show the construction of the flexible section of the
suction pipe.
Figures 25 and 26 show the construction of the extensible connecting rod or
shaft to make connection of the excavator implement with the driving-shaft on
the scow.
Figures 27 and 28 show the construction of the spud anchors for holding the
scow in position, their application is seen in figure 1.
Figures 29 and 30 show the fixed guides on the swinging beam to control the
movements of the extensible connecting rod.
The barge or scow (figures 1, 2, 20, and 21) has a well or opening with a movable
tank, B, that fits between guides on the sides of the well and while thus confined
is free to be raised and lowered by suitable mechanical means.
In this tank are placed the suction-pump, the machinery for moving and
handling the crane and for driving the excavating implement, and upon a foot or
extension of the tank-bottom is set the step-bearing g' for the heel of the crane.
A set of hydraulic jacks D, D, (figures 1,2 20, and 21,) are placed on platforms, d,
in the tank above the pump-pit with their heads or plungers resting against cross
timbers A that form a part of the fixed frame-work of the barge and thereby give
points of resistance for the jacks. When worked simultaneously the four jacks
cause the tank to move within the barge-well and produce submersion to a greater
or less depth accordingly.
This manner of mounting and setting the pumps and other mechanism connected
with and pertaining to the dredging apparatus affords complete adjustment and
control of their position with relation to the depth of the bottom or dredge matter
below the water surface and to the variation of such depth during work.
The remainder of the barge space is of suitable size to accommodate furnaces
and boilers, coal bunks and room for the men,
The swinging crane G G¹, consists of the upright mast or frame G set into the
bearing at the heel and supported at the upper end by a socket-bearing g³ on
the frame-work; through this socket it is free to slide as the bearing g' on the
tank is raised and lowered.
The crane has lateral movement in a circle from these two points.
At the upper part is fixed a boom G¹ supported by braces, and from the outer
end of which the excavator or beam is suspended and carried by cords and
pullies H, h. This beam, F, is attached at, f, to the mast by a hinge joint and on
this point it is movable in a vertical arc. The combined movements of the crane
and the beam afford ready adjustment of the excavator on the end of the beam
into any position for action.
The power to rotate the excavator and move the crane is located on the barge, A,
and the connecting mechanism is placed partly on the tank-section and partly on
the crane; it is therefore necessary to employ such means of connecting the
excavator driving-shaft with the power-shaft as will accommodate the movements
of the beam both laterally or from side to side, and in a vertical arc. For such
purpose I make use of the mechanism shown in detail in figure 3 sheet 1. In this
the upright shaft, G is mounted on bearings on the upright frame of the crane, and
has double gears K, k, of which one (k) engages with a bevel gear L', on the
excavator-shaft L and the other (K) meshes with a pinion M³, on the short
horizontal shaft M, situated on the barge tank. This shaft (M) is connected by
the universal coupling O to the engine-driven shaft N; the two shafts L and M
are therefore always connected, while the crane swings on its pivot.
Lateral movement of the crane to carry the excavator in its horizontal arc is
effected by means of a set of winding drums T and cables w, w, connected to.the'
!

page_text: outer end of the beam F. The drums (T2) are loose on the shaft T, but are locked
to it by a sliding clutch T between them. In the middle position of this clutch,
both drums are at rest while the shaft is continuously rotating; but one drum or
the other is brought into action to draw in the cable according as the sliding clutch
is moved against the clutch-face of one or the other.
The drum-shaft T, is connected through the counter shafts S¹ and worm
gearing R, S, with the engine shaft P. The proportions of these gears are such
that in a given number of revolutions given to the excavator the winding-drum
when locked to the drum shaft will rotate a certain amount or portion of a
revolution, the effect of which is to draw the beam F a given distance forward, or
in the direction of the cutting being done by the excavator, and thereby auto-
matically feed or give progression to that implement in a curved path. By one
drum and its cable this feeding is produced, and by the other the beam (F) is
drawn back again when it has reached the limit of its travel.
The beam (F) is a ladder-like frame composed of parallel beams f*, f*, with
cross-bars at intervals on which the suction-pipe is carried, and it is suitably
strengthened by braces and trusses.
The rate of speed of the winding drums is increased or diminished by varying
the proportions of the gears, and the feed of the excavator can be regulated
accordingly.
Connection of the driving-mechanism with the shaft L is made by an extensible
connecting rod or shaft of peculiar construction the details of which are shown in
figures 25 and 26 of the drawings. The center portion W is tubular and a sliding
rod (WW) with the half of a universal coupling Q on the end is fitted into each
end of the tube. The bore of the tubular rod is square or polygonal, and the ends
of the sliding sections are of corresponding shape, so that the whole structure turns
as one rod, while the end sections are movable longitudinally to increase or reduce
the length. The center section bas trunnions W₁ with slotted ends W to fit over
the edge of curved guides Y, Y, that are secured upon the tops of the side bars f*, f*,
of the ladder-frame; this construction affords a double movement of the center
part W, viz-a longitudinal one, permitted by the sliding movement of the
trunnions, and an oscillating one of the part on these centers, by which the whole
rod accommodates itself to the elevation and depression of the ladder frame in the
vertical arc.
By this connection the driving mechanism to rotate the cutting portion of the
excavator can be located at any convenient point above the joint or center of the
ladder-frame, and the suction-pipe and connections can be then brought so close to
this center of movement that the smallest amount of flexure in such pipe will
result from the extreme conditions of movement of the excavator in a vertical arc
and of the crane in a horizontal arc.
The automatic indicator to show the depth of the outer end of the excavator
carrying beam (F.) below the surface of the water, is fixed on the upright frame of
the crane, and is composed of the parts shown in figure 11. of the drawing. The
two levers m³ m³ move on centers against one of the posts of the frame G, one
above the other and are connected together at the outer ends by a link me. The
lower lever is connected at its outer end to the pivoted ladder fraine (by m) at a
point beyond the pivot; while the corresponding end of the upper lever is attached
to the end of an upright sliding rod m, carrying a pointer p. As the ladder-frame
rises and falls this pointer p has an equivalent movement alongside of a scale, t,
the divisions of which are proportioned to the length of the are traversed by the
excavator in the movement of its ladder frame from the horizontal or water-line
down to its lowest point of depression under the water; these divisions of the
scale being graduated to feet and fractional parts.
The excavator or dredging implement is of that construction having an internal
stationary part or drum which is secured to the end of the ladder frame, and an
outer revolving shell or cutting cylinder fixed to a driving-shaft and armed with
scoops, buckets or cutting edges surrounding openings in its peripheral surface,

page_text: The driving shaft passes longitudinally through the axis of the stationary part and
at the outer end is fixed in the head or closed end of the cylinder.
The mud or matter taken up by the cutters during the rotation of the shell is
discharged through the inlet apertures into a longitudinal chamber formed in the
stationary drum and connected at the rear end with the suction pipe through
which this dredged matter is drawn away and raised to any distant point of
discharge.
The suction chamber is in two separate compartments through one of which a
portion of the scoops or cutters are emptied and have their borings or cuttings
drawn off while the other passage acts in like manner for the remaining portion.
By this construction the cutters at the extreme end and farthest from the suction-
pipe receive the full force of the suction and are cleared of matter equally as well
and rapidly as those next the end of the suction pipe.
As shown in the construction figures 13 to 19 inclusive, the drum or stationary
part has solid flanged heads a, a¹, and a hub a', with bearings at each end of the
rotating shaft, and the head b of the revolving shell is fixed to its outer end.
Beyond its journal portion c¹ the shaft is reduced in thickness to produce a
water-chamber d, and the pipe D communicating with a suitable water-head or
pressure outside is connected to carry a water-jet into the surrounding chamber at
this point to cool and lubricate the bearings.
Of the two separate suction compartments A³ A', one leads to the outer end and
the other terminates about half-way, and they are produced by the partition a³, aº,
running from the outlet longitudinally and then transversely across.
The suction pipe J E for a portion of its length is likewise divided into two
separate passages e, e, by a longitudinal partition E and at its termination the
passages merge into one general cylindrical conducting passage. This point is
sufficiently distant from the end of the pipe to give a gradual contraction of the
area of the two passages into the single cylindrical portion.
The leading edges, of the suction chamber are provided with removable cutting
blades, one G along the side and the other G' across the end, and they are fixed by
screws to be removed when worn, and for sharpening as required.
The suction pipe being rectangular at the end where it joins the drum is fixed
by a flange to the outlet, and from this end it runs into the conical and finally
takes the cylindrical shape from the double passage, whence it continues of uniform
diameter to the end where the suction pump is connected. This tapering portion
is divided longitudinally by the partition E¹, that forms a continuation of the
partition in the suction-chamber of the drum so that by regular contraction the
two suction passages are brought into one at the termination of the partition E'.
The revolving shell has inlet apertures around which are fixed the scoops or
buckets F F, with cutting edges. In addition to the buckets it is armed with
projecting cutters or fin-like blades, H H on its periphery having curved edges and
a projection at least equal to the buckets.
They are fixed in front of the buckets in line with their plane of rotation and
are secured by means of plates h, h, in which are dovetail slots to take the corre-
spondingly formed ends of the blades; these plates being bolted to the surface of
the shell at intervals apart.
The blades when set with their higher edge leading perform the office of guards
to protect the cutting edges of the buckets, and when reversed they serve as cutters
to act upon the material in advance of the buckets.
In the drum (A) all that portion of the interior space not taken for the suction
chamber is made an air-tight compartment. This is the space A' between the
heads a, a, the outer wall of the drum and the walls of the chamber A'.
The head of the revolving shell is secured to the end of the driving shaft (C C,)
by which the shell is rotated upon its drum. The end of this cutting device is also
provided with inlets and buckets and these deliver the borings or cuttings into the
end of the passage or division of the suction chamber, A* A*,

page_text: All the inlets and their buckets are arranged in a spiral manner or so as to
alternate one row with another.
The suction pipe is composed of a flexible section C³ that has the quality of
universal flexure to bend in any direction and for the remainder of its length out
to the connection with the suction chamber it is an inflexible pipe; this part
however is capable of a lateral movement upon its supports f*, f*, as the
section J, is joined to the section J, E by the ball-and-socket joint. Thus while
the outer section at the excavator is stationary the other section can shift its
position sidewise on its supports under conditions of change in the position of the
crane. Such movement of the suction-pipe reduces the curvature of the flexible
section under the movement of the crane in the horizontal arc and there is con-
sequently less strain upon the pipe and less change in the internal area of the
flexible section than if the section were stationary.
The flexible pipe is formed of rubber or combination of rubber and fibre such as
is generally employed in the manufacture of hose and with this material is
incorporated a skeleton or frame of metal composed of rings B, C, (fig. 23,) embedded
in the material in such manner as to strengthen and preserve the cylindrical form
without interfering with the required flexible quality. In the drawings figures 23
and 24, A, represents a layer of rubber forming the interior surface; B B, are
separate rings of metal preferably round in cross section and laid at regular
intervals. A thick layer or several layers of material, A', covering the rings and
filling the spaces between them being next applied, the second series of rings is
placed over this filling in such manner as to alternate with the other series, and
a final covering, A, forms the outside of the pipe.
For this last covering rubber cloth or rubber and canvas or material of like
qualities is employed. This pipe is capable of withstanding a high degree of
pressure and will retain its cylindrical form under all conditions of curvature.
Figures 4, 5, 6, 7, 8, 9, 10, show the suction pump. This pump consists of two
parts, viz: a stationary outer case A A* and a revolving block, B, of hemi-
spherical shape filling one half of the case and having rotary motion therein from
the shaft C, C, that extends through the case and is connected at the outer end to
suitable driving power.
The case is in two parts, one being filled by the rotating block and the other
forming a chamber of full area except at the center where the shaft and hub of the
block is placed. A flange joint and bolts unite these parts.
At and through the bottom of the block is an inlet with a circular mouth
surrounded by a tubular extension or nozzle, A³, to which the suction pipe is
coupled. At the opposite end of the case is a tubular elbow or curved nozzle A³,
and the form of the chamber in this part is somewhat conical to give a conductor
of gradually contracted area from the point where the material leaves the mouth
of the spiral passages in the block up to the discharge opening.
The inlet and outlet openings are carried to one side of the axis to bring the
shaft C. out at the center. At these points are glands or stuffing boxes D.
At these points also are water joints and connections of water-conducting tubes
by which jets or streams of water under suitable pressure are carried and applied to
the moving surfaces to keep thm clear of sand and gritty matter, and the joints
continually bubricated.
The water tubes d', d³, enter at the sides of the bearings and connects with the
supply-pipe E, above.
The center of the block (B) arround the mouths of the spiral passages is a
cylindrical hub B', fitting in a seat of corresponding form in the bottom of the
chamber. At this point also a water jet is applied through the pipe d³, entering
the side of the case.
A similar pipe entering at d³, carries a jet into the space between the walls of
the chamber and the block.
The centrifugal passages, B³, run with a regularly increasing spiral around the axis
of the block; but instead of holding the same pitch out to the end, they are

page_text: deflected as they pass out at the face of the block, so as to turn their mouths
forward or in a contrary direction and with an acute deflection.
This change of curvature is produced by setting into and securing against the
flat face of the block an annular piece H produced from an inner and an outer
ring h, h, and inclined partitions that divide the annular space into inclined
passages, h, equal in number to the spiral passages in the block. The top face of
the block has a rim B³ of the same width as the rim of the piece H. The bottom
faces of the partitions are flat and flush, to set closely against the block B, while
their upper faces h°, bave an inclination from the bottom of the opening h² up to
the top of the rim. At this end the partition overhangs the opening and the face
or wall his under-cut on the curve as seen in figures 9 and 10.
Instead of being made in two pieces, however, the block and this part H could
be cast solid; but being made in two separate pieces it is possible to vary the pitch
of the discharge ends of the centrifugal passages by simply changing the pieco H.
The block (B) has a hollow spindle B' to slip on the shaft (C, C.) and over this
center is fixed a cone I that fits within the inner ring (h) of the piece (H) and
rests against the block. Bolts J, J hold this cone in place the heads of which set
into the recess k, and are covered by the conical tip K, to complete the hub and
continue its curved lines forwards and inwards smoothly to the shaft.
A wearing ring, L, is placed between the two flanges of the joint in the case to
take the wear of the rotating block and protect the edge of the case.
the hub B of the block is also formed of a removable piece M.
The seat for
These two parts are taken out when worn, and replaced by new surfaces. The
part M is a ring with an internal groove at the line of the joint and a pipe d'
supplies water to the passage thus produced.
Removable wearing surfaces are also applied to the faces of the inclined partitions
of the pieces H, consisting of the shoes h, which are set into dovetail grooves as
shown in figures 9 and 10, and they may be made of rubber, glass or metal,
The pump is set within the pit of the tank B fig 1, and is connected with the
suction pipe, J, on the crane through the medium of the stationary coupling
section C that projects through the end of the tank and is provided with two
branches C' by means of which one or two pumps can be coupled to the suction
pipe to increase the force as circumstances may require.
In the use of dredging boats and apparatus of such character it is customary to
anchor the dredge boats by means of spuds or small piles which are driven down
into the mud against the sides of the boat or through wells or openings in the hull;
and in moving the boat as the dredging progresses these anchors are drawn up and
driven again when the position of the boat is changed. To facilitate the driving
and extracting of such spuds I employ the device or means represented in figures 1,
27, and 28 of the drawing's, consisting of frames or guides Z³ set upright against
the sides of the boat and carrying sheaves Z Z at top and bottom around which
are bent in each frame a chain or cable Z' having its ends secured to the head or
upper end of the spud (X). The top sheave is at sufficient height above the water
line to draw up the spud clear of the bottom. By applying suitable power to this
endless cable in either direction the spud is readily drawn up or quickly forced
into the mud or even into a bottom of considerable hardness.
When properly anchored the operation of these improved parts devices and
apparatus is carried on by lowering the beam of the crane down into the water
until the excavator is brought against the matter to be dredged.
Rotation of the excavator-driving shaft and of the pump-actuating shaft being
started, the matter is cut and is drawn upward through the suction pump from
which it is carried to any required point of discharge or deposit by means of a
conductor connected to the outer end of the pump.
The feed or advance of the excavator during its revolutions and as the cutting
progresses is effected by the winding drum (T³) and its cable at one side; its
return movement to bring the excavator back to its starting point again after each
sweep of the crane is produced by the other drum and its cable.

page_text: These two cables are coiled around the drums in a direction one opposite to the
other, and they are carried outwards beyond the sides of the boat around sheaves vl
whence they run forward to the outer end of the ladder-frama.
so
The sheaves are fixed to the ends of outriggers v that are set into sockets
that they can be thrown out or drawn in according as they are required, and as the
position of the boat may allow.
As the dredging operation continues the excavator is regularly depressed at the
end of each sweep to begin a new cut. The universal movements of the crane thus
mounted and operating permit a large extent of surface to be acted on without
frequent changes of the position of the boat.
Several parts and features of the above described machine or apparatus, among
which would include the construction of a flexible pipe by the use of skeleton
rings and a covering, also the manner of operating &c swinging boom by ropes and
winding drums; also the construction broadly of a vessel or boat with a movable
section; also the use of water lubrication in the pump and the use of a suction
pipe with branches for coupling one or two pumps, are not new and original with
me and I therefore do not claim such broadly-but only in combination.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1-In a dredging machine the combination with the swinging crane and its
ladder frame or beam, of the suction pipe to connect a pump on the boat with the
excavator at the end of the beam, with a flexible section to accommodate the
movements of the crane and its swinging beam substantially as described.
2-The combination with the swinging crane and the beam thereof carrying an
excavating implement, of an engine on the boat, the driving shaft and connections
to accommodate the movements of the crane upon its pivots and the extensible
coupling rod to afford movement up the beam in a vertical arc.
3-The combination with and upon a suitable boat or vessel of the swinging
crane and its hinged beam with the excavating implement mounted thereon; the
supporting tackle to carry the outer end of the beam; and the winding drums and
their cables having connection with the outer end of the said beam, substantially
as described.
4-The combination with the excavating implement mounted upon the
swinging crane, of the suction-pipe, consisting of a pipe partly inflexible, composed
of at least two sections united by a universal joint J', and a flexible section which
is located at the hinge or center of movement of the beam or arm of the crane,
substantially as described.
5 The suction pipe having the fixed section J E and the laterally movable or
shifting section J¹ the two connected by the universal joint J', substantially as
described.
6-The extensible rod constructed of the sections W, W³, W, substantially as
described to operate as set forth.
7-The combination with the excavating implement mounted upon the swinging
frame by which it is moved, of the shaft I, the connecting mechanism composed of
the gears K; L M¹ and the driven shaft M having connection with the engine shaft
on the boat substantially as described.
8 The combination of the boat or vessel, the movable section, B, the swinging
crane mounted on and carried by the movable section, and mechanism for raising
and lowering the section within the boat, substantially as described.
9-A dredging scow or vessel having its excavating or dredging implement and
the mechanism and apparatus for operating and handling it mounted upon a
vertically movable section which while a part of the scow or vessel is also capable
of being raised and lowered within it, substantially as described.
10 The combination with the hinged frame or beam carrying the excavating
implement, of the indicator applied to operate substantially as described.

page_text: 11-The rotary excavator consisting of the stationary drum or barrel BE, with
an outer revolving shell which is provided with inlets and surrounding buckets or
cutting scoops, and is caused to rotate upon the said drum by means substantially
as described, the said drum having a suction chamber that is connected with the
pipe or conductor from a suction pump.
12 The drum having a divided suction chamber and the suction pipe having
independent passages one for each division of the suction chamber substantially as
described.
13-The excavator drum having the long hub, d, the driving-shaft with the
portion of reduced diameter and a water pipe D, substantially as described.
14-The revolving excavator having peripherial buckets or cutting scoops F F,
and the cutting blades H mounted on the surfaces of the excavator substantially as
described.
15 In combination with the stationary drum the inserted cutting edges G, G+,
substantially as described.
16-In combination with the drum A having the divided section chamber A³, A*
the suction pipe J E, having the tapering passages and cylindrical extensions
forming the conductor of uniform diameter substantially as described.
17 The suction pipe E figures 17, 18, of rectangular shape or the mouth with
the longitudinal partition E', and the cylindrical continuation substantially as
described.
18 The excavator-drum having the air-tight chamber A² (figures 14, 15, 17)
and suction chamber as described.
19 The suction pump consisting of the outer stationary case A A*, the
centrifugal block B with spiral passages, and the driving shaft C C, substantially
as described.
20 In combination with the outer case and the centrifugal block B, the
removable bearings I M, in the case substantially as described.
21 The centrifugal block B with radial spiral passages B', and the circular
hub B' forming the journal for the base of the block substantially as described.
22-In combination with the case A A* and its block B (figures 4, 5, 6,) the
water pipe d³ substantially as described.
23 The centrifugal block with spiral passages of which the pitch or inclination
has an acute change in an opposite direction at the discharge end, substantially as
described.
24 The combination with the centrifugal block B, of the annular parts B,
substantially as described.
25-The combination of the stationary case A, A* with axial bearings for the
driving-shaft, and the centrifugal block, rotated by said shaft but having a
support and bearing composed of the hub B and the seat M, substantially as
described.
26-The combination with the mouths of the radial passages in the centrifugal
block, of the removable wearing surfaces h* (figures 9, 10,) substantially as
described.
27-The combination with the spud X (figures 27, 28,) of the endless chain or
cable and the fixed sheaves, substantially as described.
28 The improved dredging apparatus constructed and combined togather for
operation, and the manner of operating the same, as set forth.
Dated this Twelfth day of August 1884 -