Improvements in and relating to Excavators.
Year: 1898

page_text: Date of Application, 6th Jan., 1898-Accepted, 26th Feb., 1898
[Communicated from abroad by EDWARD BOCK and LAWRENCE NIVEN JACKSON, both
in the Royal Railway Department, Bangkok, in the Kingdom of Siam,
Engineers.]
Improvements in and relating to Excavators.
I, CHARLES JUNGE, of Lincoln Chambers, 75, Chancery Lane, London, W.C.,
Consulting Engineer, 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 invention relates to excavators.
In the construction of canals, especially in flat countries the richness of whose soil
is to be opened up by canals, the making of waterways is rendered expensive, because
the system of excavators heretofore used is costly and necessitates in particular very.
considerable working expenses. For instance in the case of a canal having a top
width of sixteen metres, a depth of two and a half metres, and a bottom width of
eight metres, use is made of two excavators, one on each bank, which weigh singly
about thirty five tons and have an engine of thirty horse-power. For this weight of
thirty-five tons it is necessary to have a correspondingly heavy track the construction
of which in flat countries, especially in the rainy period, occasions great difficulties
and outlays. Moreover, the continual transport of the rails to the front of the
excavator on the wet soil just dredged and the relaying of same are attended with
considerable difficulties. The great weight of the single excavators employed up to
the present time is due to the necessity for balancing the overhanging of the bucket
mechanism.
By the improved excavator constructed according to my said invention all these
inconveniences are obviated and important advantages are achieved.
This excavator is represented in the accompanying drawing,
Figure 1 being a front elevation and
Figure 2 a plan of the machine.
In carrying this invention into practice I combine in a suitable manner the
excavators formerly placed independently on the two banks of the canal. For
this purpose I employ a girder or bridge A, the length of which exceeds the width of
the canal to be dredged by the width of a small truck d on either side. This girder
or bridge A serves for the reception of the engine and boiler b, the two bucket
mechanisms E being arranged on either side of said girder or bridge. The transmis-
sion of motion from the engine 6 to the bucket mechanism takes place in any desired
manner by means of a main shaft extending to both sides, such shaft transmitting
its rotary motion by bevel or sprocket wheel gear to the drum of the bucket
mechanism.
As shown in the drawing, the engine is preferably put up under cover, the room
containing it serving at the same time if desired for storing up the requisite tools,
implements and the like.
For facilitating the transport of the track from the rear of the excavator to the
front and also for conveniently relaying the rails I arrange moreover on either

page_text: side of the bridge A a crane c, the operation of which will be understood from
the drawing.
In order to render the same excavator suitable for different widths of canals, the
girder or bridge A is furnished at. its two ends with removable parts so that the
length of such girder or bridge may be prolonged or shortened according to the width
of the canal.
The chief advantages resulting from the arrangement of this improved excavator
are as follows:
Besides reducing the cost of manufacture and working, I simplify the transport of
the whole machine, having regard to the comparatively small weight of same. When
using the improved arrangement the distribution of pressure is much more favourable
than heretofore; because a smaller weight is distributed to the two banks of the
canal. Contrary to what has hitherto taken place, there is no pressure against the
walls of the canal, but in the direction perpendicular to the ground. It cannot
therefore happen, as is the case with the excavators used up to the present time, that
the weight of. the machine bears against the half-dredged canal, causing considerable
disturbances in the working. By the use of the girder or bridge the entire
arrangement, as regards the distribution of weight, is balanced in a proper manner,
so that, even with the most unfavourable conditions of subsoil, the sinking against
the canal cannot occur. It will be readily seen that by reason of the advantageous
distribution of the load a lighter track may be employed. As regards attendants
during the working, a saving of one-half is effected, because there is only one
machine, and one man is sufficient to. control the entire arrangement. A similar
advantage is achieved by the use of the cranes for relaying the rails.
In short the progress. achieved as compared with the well-known arrangements lies
in performing the same amount of work with smaller cost of manufacture and at
about half the working expenses...
Having now particularly. described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondents, I declare that what I claim is:
"
First. An excavator characterized by the arrangement of the bucket mechanism E
at both ends of a girder or bridge A supported by trucks d, which girder or bridge
extends transversely over the canal and serves for the reception of the engine b,
substantially as set forth.
Second. An excavator characterized by the feature that cranes c designed for
relaying the rails are arranged at both ends of the girder or bridge A, substantially
as set forth.
Third. An excavator characterized by the feature that the ends of the girder or
bridge consist of several parts adapted to be removed according to the width of
the canal with the object of varying the length of such girder or bridge, substantially
as set forth.