Improvements in Excavating or Dredging Machines.
Year: 1892

page_text: Date of Application 22nd Apr.. 1892-Accepted. 4th June. 1892
COMPLETE SPECIFICATION.
Improvements in Excavating or Dredging Machines.
A communication from ARTHUR BRAUN, of Dautzschen, in the Empire of Germany,
Builder.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Member of the Institution of Mechanical Engineers, 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 :-
This improved excavator or dredger differs from machines of the same class
hitherto known in the peculiar arrangement and method of operation of its operative
mechanism proper which consists of a number of knife-edges acting much in the
same manner as the cutters of ordinary wood-cutting or shaping machine tools.
These knife-edges are arranged constantly to revolve about a longitudinal shaft
having its bearings in the elevator apparatus, and in so doing they cut, or dig up
the earth or mud, raise it, and convey it into suitable carrying apparatus (a bucket-
chain, conveyor-screw, etc.). This constitutes an essential difference from the old
machines of this class, which operate intermittently with the exception of those in
which bucket-chains are employed. These, however, as hitherto constructed, have
not been found applicable to a somewhat hard ground for which the present machine
is suitable, while the advantages arising from a continuous operation, as compared
with the usual intermittent action, are obvious and need not further be dwelt
INAN
Fig. 3 a cross-section of the same.
A is the frame, B is the motor-engine and C the elevator turning about the
shaft a and capable of being raised or lowered as required by means of a winch D.
In the form of apparatus here shown the elevator is constructed of two U-shaped
iron cheeks with high edges (Fig. 3).
Between these cheeks a bucket-chain E is
arranged to run upon the driving-shaft a and another shaft b. Upon the elevator
is placed the bearing c Fig. 1, while at its lower end there is a plate with journals
or pins d. These two latter parts serve for supporting the cylindrical body e
carrying the digging or cutting blades. e is an openwork, hollow cylinder con-
sisting as shown of a number of bars forming a cylindrical grate or cage, each bar
being provided with excavating blades ff arranged in a row. The perforations of
the cylinder wall, or the spaces between the bars in the present arrangement, serve
for allowing the earth or mud raised by the knife edges or blades to drop through
the cylinder into the intermediate space between the angle-irons, or in other words
upon the bucket-chain. The body è is revolved by means of the bevel gearing gg
and the pitch-chain h from the main shaft a and the transmission of motion is so
regulated that the bucket-chain moves at a comparatively rapid rate, in relation to
the speed of motion of the excavating blades. The object of this is to accelerate
the removal of the lumps of earth or the like cut or dug up by the said knives, to
avoid the accumulation of a too heavy load upon the elevator, so that a comparatively
small and light bucket-chain may be sufficient to perform the work, and a proper
proportion is at all times maintained between the quantity of material raised by the
blades and that which is carried away. In Fig. 3 are shown inclined sheets of
metalii situated upon the upper edge of the angle-irons in such a position as to
form a hopper which facilitates the conveyance of the material to the buckets.
e
The arrangement here described may vary in the details of construction, arrange-
inent, size and shape to suit requirements without departure from the principle of

page_text: the invention. Thus, as before suggested, a conveyor-screw or any other similar
device may be employed instead of the bucket-chain. Again no limit is placed on
the number, shape, or size of the excavating tools.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner the
same is to be performed, I declare that what I claim is,-.
1. An excavator or dredging machine by which the earth or material is cut or
dug up by means of a number of knife-edges or blades such as ff and then
conveyed into a suitable carrying and discharging apparatus substantially as
described.
2. In an excavator the combination with a revolving excavating tool of an
elevator inside the tool substantially as described and illustrated in the accom-
panying drawings.
3. A. continuous dredging or excavating apparatus substantially as described and
illustrated in the accompanying drawings.
Dated Lin 11
e
$11000
W. P. THOMPSON & BOULT,
Agents for the Applicant.