IMPROVEMENTS IN HOPPER DREDGERS
Year: 1883

page_text: LETTERS PATENT to Andrew Brown and William Simons of the town and
County of Renfrew, North Britain, Engineers and Shipbuilders, for an
Invention of "IMPROVEMENTS IN HOPPER DREDGERS
"
PROVISIONAL SPECIFICATION left by the said Andrew Brown and William
Simons at the Office of the Commissioners of Patents on the 20th June
1883..
ANDREW BROWN and WILLIAM SIMONS, of the Town and County of Renfrew,
North Britain, Engineers and Shipbuilders, · "IMPROVEMENTS
- IN HOPPER
DREDGERS
"
This Invention, which relates to improvements in hopper dredgers, has mainly
for its objects, firstly; the saving of the great cost for repairs, which usually takes
place when dredging blasted or disintegrated rock or boulder stones or material of.
a character destructive to the dredger's buckets or machinery, which is effected by
the bucket ladder being suspended by links and regulating screws.-This allows
of a rocking motion and enables the buckets to recoil when meeting with material
of a character destructive' to the inachinery or buckets. And secondly the object
of the Invention is to facilitate the propulsion and navigation of hopper dredgers
which have their buckets projecting at bow or stern to cut shoals or the vessel's
own flotation-This is effected by constructing the bucket ladder so that it can be
withdrawn into the interior of the well, and placed on the level of 'the deck when
steaming with a load, or when doing, repairs,-the bucket ladder. being' suspended
by connecting links, and moved up and down by means of screws.and nuts, rack
and pinions, or other similar means, driven by hand or steam or other power wlien
required.
The framing of the dredger, can be constructed with a curved opening, to allow
the upper end of the bucket ladder to be traversed backward and forward when'
required.
In place of having the hopper cavity as at present with doors in the vessel's
bottom, we make the hopper cavities on each side of the vessel, with the doors at
the sides or bilge, and thus the vessel can discharge its load at its own draught of
water and further the doors can be more readily repaired.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Andrew Brown and William Simons in the Great Seal Patent Office
on the 20th December 1883.
-Andrew_Brown_and_WILLIAM_SIMONS, both of the town and County of
Renfrew, North Britain, Engineers and Shipbuilders, "IMPROVEMENTS IN HOPPER
DREDGERS
"
This Invention which relates to improvements in hopper dredgers, has for its
objects, firstly, the saving of the great cost for repairs, which usually takes place
when dredging blasted or disintegrated rock or boulder stoños or inaterial of a
character destructive to the dredger's buckets or machinery, which is effected by
, the bucket ladder being suspended by.links..and regulating screws. This allows
of a rocking motion, and enables the buckets to recoil when meeting with material
of a character destructive to the machinery or buckets-Secondly-To facilitate
the propulsion and navigation of hopper dredgers which have their buckets pro-
jecting at bow or stern, to cut shoals or the vessel's own flotation.-This is effected.
by constructing the bucket ladder so that it can be withdrawn into the interior of
the well, and placed on the level of tho deck when steaming with a load or when
doing repairs, the bucket ladder being suspended, by connecting links, and moved
up and down by means of screws and nuts, rack and pinions or other similar
means, driven by hand or steam, or other power when required-The framing of
the dredger can be constructed with a straight or curved opening to allow the
upper end of the bucket ladder to be traversed backward and forward when
required Thirdly. In place of having the hopper cavity as at present, with doors
in the vessel's bottom, we make the hopper cavities on each side of the vessel,
with the doors at the side or bilge, and thus the vessel can discharge its load at its
own draught of water, and further the doors can be more readily repaired
In order that the said Invention may be fully understood and readily carried
out, we have shown in the drawings hereunto annexed the modes in which wo
carry it into effect.
Fig. 1. Sheet 1, represents a longitudinal section of hopper dredger constructed
according to our Invention, the bucket ladder being shown dreding boulder
C. Bucket Ladder
D. Upper framing carrying the bucket ladder and driving gear.
E. Rocking links and suspending and regulating screws.
F. Shoots.
Fig. 1. Sheet 2. represents the second part of the Invention, the same letters
denote the several parts; the ladder is suspended by the connecting links E. and
is moved up and down by means of screws and nuts, rack and pinions, or other
similar means driven by hand or steam power when required; the ladder is shown
in different positions; when dredging to full depth, when projecting out cutting
shoals, and when raised to a level with the deck.
Fig 1. Sheet 3. represents an alternative mode of carrying out the second part
of our Invention, and the same letters denote the several parts; the bucket ladder
is carried on a cross shaft E. (substituted for the connecting links E. Sheet 2) and
is traversed backward and forward when required by racks and pinions driven
by the cross shaft E. by hand or by steam power-An opening is formed in the
ladder to allow it to traverse,

page_text: Fig. 1 Sheet 4 shows our improved arrangement of hopper cavities at the sides
or bilge of the vessel, instead of in the bottom as at present the dotted linos A. A.
in the figure represent the position of the doors to the hopper cavities when
open.
Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed or carried into
effect, we claim as our Invention the improvements in hopper dredgers, substan-
tially as herein before described and illustrated by the drawings accompanying this
specification in which the important and novel points are.―
1. The arrangement of the bucket ladder as described and shown by Fig. 1,
Sheet 1, which enables the buckets to recoil when meeting with material of a
charactor destructive to the machinery or buckets.
2, The arrangement shown by Fig. 1, Sheet 2 and Fig. 1 sheet 3, by means
of which the bucket ladder can be withdrawn into the interior of the well, and
raised to a level with the deck, as and for the purposes described.
3 The arrangement of the hopper cavities and doors as described and shown
by Fig. 1. Sheet 4 as and for the purposes described
In Witness whereof we, the said Androw Brown and William Simons have
hereunto set our hands and seals this Eighteenth day of December in the year of
our Lord One thousand eight hundred and eighty three.
PG BELL Witness.
Fulbar Lane Renfrow-
5 ALEX R. PRENTICE
5 Clyde Trust Buildings
Dalmuir. Witness.
ANDREW DROWN.
(4.8.)
WILLIAM SIMONS (L.S.)