Year: 1886

page_text: I ADOLPH HORENBURGER of Ackerhof 1 Braunschweig in the Dukedom of
Braunschweig German Empire Painter do hereby declare the nature of this
invention to be as follows:-
My invention relates to improvements in dredging and excavating machines
especially "sand-drags" where large stones are absent or sparse and the objects
of this invention are:-Firstly, to provide means for allowing the buckets to follow
up the ground for a considerable distance, as the excavation advances, whereby
I avoid the necessity of advancing the machine itself until the work has proceeded
or been completed for such distance; Secondly, to facilitate the tilting and dis-
charging of the buckets ascending on the lower side of the chain; and Thirdly,
to cut or break up the ground, when necessary, preparatory to the buckets coming.
into use.
These objects are attained in the first place. by constructing a moving ladder-
shapped frame which carries the endless chains to which the dredging buckets are
secured. This frame consists of two parts hinged to each other, the upper part
being secured to the strong frame carrying the upper chain barrel and. its actuating
gearing and delivery spout on a travelling carriage or other moving or floating
frame, and without releasing the tension of the chain the ladder frame may be
bent at its hinge to any desired angle. This ladder frame is held suspended in an
oblique position, and on hoisting its upper half, by means of pulley blocks or other
tackle near the hinge, the lower half, which carries the lower chain wheels of the
bucket chains, is bent and thereby follows the excavation of the ground which has
been worked by the buckets. The hoisting action of the upper part of the frame
and the bending of the lower part being subsequently repeated, the attack or
action of the buckets will follow up the preceding excavation of the ground to a
considerable distance and by this means the carriage and framing of the machine
need not be advanced until such distance has been reached.
In order to keep the endless chains, to which the buckets are attached, in tension
when the supporting frame is bent to an increasing angle, these chains pass over
tension rollers or sheaves, which are hoisted with the upper part of the frame.
And these objects are obtained, in the second place, by securing the buckets to
the endless chains in a manner that they rise and fill the buckets on the ascending
inner angled chain, and during their upward movement with the chain they strike
against a stay suitably arranged, and are tilted to discharge their contents into a

page_text: gutter or shoot arranged to carry the excavated material off, while as soon as the
said buckets arrive at the upper end of the frame and begin to move downwards,
they automatically fall back into their previous working position and are held
secured by a suitable click or locking catch lever.
The motion of the endless bucket bearing or carrying chains may, if desired, be
made intermittent by means of intermittent gearing for the purpose of facilitating
the discharge of the buckets by hand when adhesive soil is operated upon.
And a brake mechanism may be applied to the motion of the chains entering
into action whenever the buckets have been emptied to avoid any undue motion of
the chains.
T. 1. a
And thirdly, these objects are obtained by a series of knives or cutters arranged
or mounted upon the axis of the lower chain, roller and revolving with said roller.
The said knives or cutters enter into the soil or ground to be dredged or excavated
on each side to break it up before the buckets with their sharp edges catch into it
and carry it up to the delivery shoot.
The dredging or excavating machine may be mounted on wheels and rails or
lodged in a boat to be advanced whenever the bending frame of the chain has
arrived at the end of its course and is ready to be stretched again.

page_text: improvements in Dredging and Excavating machines.
I, ADOLPH HORENBURGER, Painter, of Ackerhof 1, Braunschweig, in the
Dukedom of Braunschweig, German Empire, 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:-
My invention relates to improvements in dredging and excavating machines,
especially "sand-drags," where large stones are absent or sparse, and the objects of
this invention are: Firstly, to provide means for allowing the buckets to follow
up the ground for a considerable distance as the excavation advances, whereby
I avoid the necessity of advancing the machine itself until the work has proceeded
or been completed for such distance; secondly, to facilitate the tilting and dis-
charging of the buckets ascending on the lower side of the chain, and thirdly,
to cut or break up the ground, when necessary, preparatory to the buckets coming
into use.
These objects are attained in the manner hereinafter described, reference being
had to the drawings, in which Fig. 1 is a side-elevation of an excavating machine
embodying the improvements of my invention, Fig. 2 is a plan of the same, and
Figs. 3, 4 and 5 are detail views illustrating sundry parts of the mechanism.
In the first place the endless chains C to which the buckets are secured, are
carried by a moving ladder-shaped frame, consisting of two parts a and a¹ hinged
together at x. The upper part a of said frame is secured to the strong frame A
carrying the upper chain-barrel and its actuating gear and delivery spout n, on
a travelling carriage B or other moving or floating frame, and without releasing
the tension of the chain C, the ladder-frame a a¹ may be bent at its hinge to any
desired angle. This ladder-frame is held suspended in an oblique position, and on
hoisting its upper half a by means of pulley-blocks b¹ or other tackle near the
hinge, the lower half a¹ which carries the lower chain-wheels z¹ of the bucket-
chains C is bent and thereby follows the excavation of the ground which has been
worked by the buckets 2.
The upper part a of the ladder-frame may be held secured in any convenient
position by means of hooks at c engaging with holes or corresponding hooks of
a segment-shaped rail c¹ secured to the frame A, while the lower part a¹ of the
ladder-frame is held in its working-position by means of pulley-blocks d and e
secured to the frame A.
The hoisting action of the upper part a of the frame and the bending of the
lower part a¹ being subsequently repeated, the attack or action of the buckets
will follow up the proceeding excavation of the ground to a considerable distance,
and by this means the carriage B and framing A of the machine need not be
advanced until such distance has been reached.
In order to keep the endless chains C to which the buckets are attached, in
tension when the supporting frame a a¹ is bent to an increasing angle, these chains
pass over tension-rollers g or sheaves carried by a frame g¹, the upper end of which
is hinged to the upper part a of the ladder-frame, while the lower end of the
frame g¹ is held suspended by pulley blocks f, on hoisting which, the frame g¹, with
the rollers g, is lifted and the tension of the chains increased.
(

page_text: The chain-wheels ≈ and ≈¹ are mounted loosely on their shafts Z Z, motion is
imparted only to the shaft Z of the upper chain-barrel z in gear with a train of
driving wheels, while the lower chain-wheels z¹ are actuated by the chains.
In some cases, where heavy or cloggy, adhering soil is to be acted upon, it will
be necessary to provide for the chains C an intermittent motion, allowing to
discharge the buckets by aid of hands. Such intermittent motion may be easily
obtained by the following construction.
Upon the inner end of the driving-shaft k is keyed a toothed pinion ³ in gear
with a toothed wheel having the fourfold number of teeth of v². To the axle
the wheel v² another wheel is secured being toothed only on one half of its
circumference, the other half being smooth. This wheel v¹ is in gear with the
toothed wheel of the chain-barrel z, said wheel having the same number
of teeth as v³, but only half its diameter.
When working, the motion of the chain-barrel will be stopped as soon as the
last tooth of the wheel has come out of gear with the wheel v, and the chains C,
loaded by the weight of the filled buckets, will tend to slip back. To prevent this,
a pawls is arranged to catch at the proper time into the indentations of a disc m
secured to the chain-barrel z.
At each stop of the chain during such intermittent motion, the driving-shaft k
will be suddenly released and the gear, accordingly, will go fast. To prevent this,
I have provided an automatic brake-mechanism, to counteract by friction the
superfluous driving power, as soon as released. For this purpose an excentric
disc q is secured upon the shaft K of the gear-wheels vv and a roller p³ is held
in contact with said disc q by means of a bell-crank-lever p¹ and weight p. The
said roller p² is connected to a crank-lever carrying the brake-block p³, which,
accordingly, alternately acts against the brake-wheel y and checks the speed of the
driving gear, as soon as the wheel v¹ comes out of gear with the wheel v of the
chain-barrel z.
Instead of the brake-mechanism described, a fly-wheel of sufficient weight
mounted on the driving-shaft k might be employed to the same effect.
Where loose and dry ground or sand are acted upon, the intermittent motion of
the chains and buckets is not required, the contents of the buckets being readily
and automatically discharged. In this case the gear-wheel v¹ is replaced by a full-
toothed wheel, imparting to the chain-barrel z a continuous motion. The brake-
mechanism, in this case, is also out of use.
And the objects of my invention are attained in the second place by securing the
buckets r to the endless chains C in a manner that they rise and fill the buckets
on the ascending inner angled chain, and during their upward movement with the
chain a lever on the buckets strikes against a bracket stay suitably arranged,
and thus tilts the buckets to discharge their contents into a gutter or shoot n
arranged to carry the excavated material off, while, as the said buckets r arrive at
the upper end of the frame and begin to move downwards, they automatically fall
back into their previous working position and are held secured by the said click or
locking catch-lever l.
And thirdly these objects are obtained by a series of knives or pick cutters h
arranged or mounted upon the axis Z' of the lower chain-wheels 2', rotary motion
being imparted to said shaft by means of driving-belts at I, I', or driving-chains i
passing over pulleys i', i³, i³, i³, as clearly shown in the drawings, Figs. 2 and 5.
The said knives or cutters h enter into the soil or ground like circular saws on
each side of the buckets, to break the soil up before the buckets with their sharp
edges catch into it and carry it up to the delivery shoot.
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:
First. A dredging or excavating machine provided with a moving ladder-shaped,

page_text: each other and suspended in an oblique position by pulley-blocks, for the purpose
of being bent to follow the excavation of the ground, substantially as set forth.
Second. A dredging or excavating machine provided with a moving ladder-
shaped bending frame carrying the bucket-chains, to which chains the buckets are
hinged and secured by clicks or locking catch-levers arranged to strike in their
upward motion against a stay or stays for the purpose of automatically tilting and
discharging said buckets into a gutter or shoot, substantially as set forth.
Third. A dredging or excavating machine provided with a moving ladder-shaped
bending frame carrying the bucket-chains to which chains intermittent motion is
imparted by means of a partly toothed gear-wheel, a pawl preventing the chains
slipping back, and a brake or fly-wheel checking the speed of the driving-gear
when the chain-barrel is stopping, substantially as set forth.
Fourth. A dredging or excavating machine provided with a moving, ladder-
shaped bending frame carrying the bucket chains, the lower chain-wheels of which
having rotary knives or cutters mounted on their axle to break up the soil or
ground preparatory to the attack of the buckets, substantially as set forth.