EXCAVATING MACHINES,
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Duncan Macdonald at the
Office of the Commissioners of Patents on the 18th September 1883.
DUNCAN MACDONALD, of Glasgow, in the County of Lanark,
IN EXCAVATING MACHINES,"
"IMPROVEMENTS
This Invention relates to improvements in the arrangement of parts, and in
details of construction, of excavating machines designed for use in forming railway
cuttings, canals, or docks, and for other similar excavations.
The improved excavating machine, as adapted for forming such cuttings for
railways and other tracks, comprises a main bogie or carriage made by preference
in three portable sections, each of which is built up of deep wrought iron or steel
bars or plates which are bolted together to form an open rectangular or lattice.
frame-work. The three sections of the bogie frame are bolted or otherwise united
together longitudinally, and are carried on two, three, or more axles fitted with
railway wheels. Side wings or extensions are formed on each side of the bogie
frame, and are fitted with wheels and axles to support the same at each side. The
wheels are so disposed that they run on the two double lines of rails which are
temporarily laid for the waggons which convey away the excavated material.
Immediately over this bogie frame is fitted an upper platform of somewhat
similar construction which is connected to the lower frame by a tubular swivel
pin or boss on which the platform swivels as a centre. This platform which
carries the weight of the excavating machinery is supported by a strong rail benring
on rollers fitted on the bogie frame in the form of a circle round the swivelling
centre, and is prevented from canting forward when the load is on the excavating
machinery, by means of or strong segmental flange secured to standards on the
bogie frame, against the lower side of which a series of rollers on the swivelling
frame bear. The upper platform is also built in sections which are connected
longitudinally narrow openings being left between the plates which are bolted
together, into which openings are fitted strong vertical standards forming part of
the framework of the excavating machine. The standards are formed with
shoulders which rest on the plates at each side of the joint openings, and are
secured to the swivelling frame by bolts passing through them and through the side
plates of the frame.

page_text: The framework of the excavating machine is of triangular form or somewhat
similar to that of an ordinary dredger, and it is arranged to carry a chain or chains
of dredger buckets or buckets and picks alternately. The dredger chain is formed
of two or more series of long steel links connected by steel pins, and the buckets
are by preference cast of steel in a piece with those links to which they have to
be connected, the picks being also cast on a corresponding set of links, while plain
links connect the buckets and picks alternately. The buckets and picks may
however be rivetted or otherwise attached to the links of the chains. Each pick is
formed with four members which are connected near each end of the parallel bars
of double links, and which unite together and terminate in a single point. The 1
chain of picks and buckets traverses an inclined path both in the upward and
downward directions, but in the front of the machine they rise in a vertical or
nearly vertical path while digging or excavating. The weight of the chain and of
the filled buckets and picks is supported by a series of rollers fitted across the
front and upper side of the machine framework, and in its descent the chain is
guided and supported by rollers fitted on each side and clear of the buckets and
picks. At each corner of the triangular frame the chain passes over large guide
wheels or rollers, the upper of which is driven by means of gearing and imparts
motion to the chain.
The buckets discharge their contents into segmental troughs or shoots fitted
above and round the swivelling centre, and which discharge into an inclined shoot
jointed at its upper end close under the point at which the buckets are canted to
the upper end of inclined standards fitted at the back of the bogie frame. The
inclined shoot is supported towards its lower end by rollers fitted under it, which
bear on a rail carried by a bracket on the standards, and it is arranged to swivel
on its joint above, so that the lower end of the shoot may discharge into the
waggons at either side or on either line of rails behind the machine.
A steam boiler supplying the steam engine which operates the machine is fitted
on the swivelling frame under the inclined shoot at the rear end, its weight serving
partly to counterbalance the load on the excavating buckets. The steam engine
is conveniently fitted between the main upright posts of the machine frame over
the swivelling centre and it actuates a crank shaft supported in the uprights and
fitted with gearing from which the wheel or roller driving the bucket chain is
operated, by which also the bogie frame is driven through suitable gearing, and
by which a swivelling motion can be imparted to the main platform and framework
on the central pivot by means of gearing acting on a toothed segment or internal
toothed wheel fixed on the bogie frame. Clutches are provided for reversing and
for throwing out of gear any of the parts which it may be wished to stop.
A peculiar feature of the machine is that the cutting operation effected by the
buckets proceeds continuously, while the main frame with the buckets is made to
swivel slowly round and bring a fresh surface in front of the rising buckets and
picks.
To enable the machine to effect the sloping or finishing of the sides of a railway
or similar cutting, the front part of the triangular framing carrying the chain of
buckets for forming the cutting face is arranged to swivel on the centre of the
lower guide roller of the chain and to drop out at an angle to the horizontal plane,
equal to that of the slope to be given to cuttings and embankments. A spare tie
bar carried on the machine is fitted on each side of the frame to connect the inclined
upper part of the structure to the swivelling front part, and a few additional links
are put into the chain to give it the requisite extra length.
Instead of fitting the improved arrangement of excavating machinery on the
swivelling platform described, it may be fitted on a platform having a traversing
movement both longitudinally and transversely, or any ordinary construction of
platform may be used, and when the machine is adapted for cutting the banks of
Canals or rivers, a floating platforın may be used.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Duncan Macdonald in the Patent Office on the 17th March 1884..
DUNCAN MACDONALD, of Glasgow, in the County of Lanark "IMPROVEMENTS
IN EXCAVATING MACHINES."
My said Invention relates to improvements in the arrangement of parts, and in
details of construction of excavating machines designed for use in forming railway
Cuttings, Canals, or docks, and for other similar excavations.
My Invention is illustrated in the accompanying Drawings in which Figure 1
is a side sectional Elevation of one modification of the improved excavating
machine. Figure 2 is a transverse vertical section taken on the line 1-1 in
Figure 1. Figure 3 is a horizontal section on the line 2 - 2 in Figure 1.
Figure 4 is a plan of the carrying frame, and Figure 5 represents in plán a detailed
view of the shoot and guide plates which lead off the material dropped from the
excavator buckets.
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The improved excavating machine, as adapted for forming such cuttings for
railways and other tracks, and as illustrated in the Drawings, comprises a main
bogie or carriage made by preference in three portable sections A, A', A¹; each of
which is built up of deep wrought iron or steel bars or plates which are bolted
together to form an open rectangular or lattice frame-work. The three sections
A, A¹, A¹, of the bogie frame are bolted together to form an open rectangular or
lattice framework. The three sections A, A1, A2, of the bogie frame are bolted
or otherwise united together longitudinally, and are carried on two, three, or more
axles B fitted with railway wheels B¹. Side wings or extensions All are formed
on each side of the bogie frame A, A¹, and are fitted with wheels B', and axlės,
to support the same at each side. The wheels B1, B2, are so disposed that they
run on the two double lines of rails R which are temporarily laid for the waggons
which convey away the excavated material. Immediately over this bogie frame
A, A¹, is fitted an upper platform D of somewhat similar construction, which is
connected to the lower frame by a tubular swivel pin or boss E on which the
platform D swivels as a centre, this pin E fitting into a socket in the lower
frame A. The platform D which carries the weight of the excavating machinery,
is supported by a strong rail F bearing on rollers f fitted on the bogie frame A, A¹,
in the form of a circle round the swivelling centre E, and is prevented from canting
forward when the load is on the excavating machinery, by means of a strong
segmental flange G secured to standards G¹ on the bogie frame against the lower
side of which a series of rollers g fitted on the swivelling frame, bear. The upper
platform is also built in sections D, D¹, D¹; which are connected longitudinally,
narrow openings d being left between the longitudinal plates which are bolted
together, into which openings d are fitted strong vertical standards H forming part
of the framework of the excavating machine. The standards H are formed with
shoulders h, which rest on the plates at each side of the joint openings d, and they
are secured to the swivelling frame D by bolts passing through them and through
the side plates of the frame.
The framework H' H', of the excavating machine is of triangular form, or
somewhat similar to that of an ordinary dredger, and it is arranged to carry
a chain or chains J of dredger buckets K and picks L alternately. The dredger
chain is formed of two or more series of long steel links J, J', alternately single
and double, and connected by steel pins j, and the buckets K may be cast of steel
in a piece with those links to which they have to be connected, the picks in that
case being also cast on a corresponding set of links J', while plain links J connect
the buckets K and picks L alternately. The buckets K and picks L may however

page_text: be rivetted or otherwise attached to the links J' of the chains. Each pick L is
formed with four members l, l, which are connected near each end of the parallel
bars of double links J, and which unite together and terminate in a single point.
The chain J J¹ of picks and buckets traverse an inclined path both in the upward.
and downward directions, but in the front of the machine they rise in a vertical
or nearly vertical path while digging or excavating. The weight of the chain J, J¹,
and of the filled buckets K and picks L is supported by a series of rollers M fitted
across the front and upper side of the machine framework H¹, H³, and in its
descent the chain J, J¹, is guided and supported by pulleys M' fitted on each side
and clear of the buckets K and picks L, the buckets being formed with flanges k
to ride on the wheels. At each corner of the triangular frame H1, H2, the chain
passes over large guide wheels or pulleys N, the upper of which is driven by
means of gearing O, and imparts motion to the chain J. The buckets K discharge
their contents into segmental troughs or shoots P, fitted above and round the
swivelling centre, and which discharge into an inclined shoot P¹, jointed at its
upper end by a pin p (close under the point at which the buckets are canted) at
the upper end of the inclined standards G¹ fitted at the back of the bogie frame D.
The inclined shoot Pi is supported towards its lower-end by rollers p¹ fitted under
it, which bear on a rail forming a water tank P2 carried by brackets P³ on the
standards G¹; and it is arranged to swivel on its joint p above, so that the lower
end of the shoot P¹ may discharge into the waggons at either side, or on either
line of rails R behind the machine. A steam boiler S supplying the steam engine S¹
which operates the machine, is fitted on the swivelling frame D under the inclined
shoot P at the rear end, its weight serving partly to counterbalance the load on
the excavating buckets. The steam engine S is conveniently fitted between the
main upright posts H of the machine frame over the swivelling centre E, and it
actuates a crank shafts supported in the uprights H and fitted with gearing 01
from which the wheels or pulleys N driving the bucket chain are operated through
the counter-shaft O' and bevel gearing-0. The Engine also drives the bogie
frame A through the spur gearing T, shafts T1, T2, and bevel gearing T3, T4 ; and
a swivelling motion can be imparted to the main platform D and framework H, H',
on the central pivot E by means of the gearing U, U₁, acting on a toothed segment
or toothed wheel U* fixed on the bogie frame. Clutches V actuated by hand
levers are provided for reversing and for throwing out of gear any of the parts
which it may be wished to stop.
A peculiar feature of the machine is that the cutting operation effected by the
buckets K and picks L proceeds continuously while the main frame D D¹, H,
H, H, with the buckets is made to swivel slowly round, and bring a fresh surface
in front of the rising buckets and picka
To enable the machine to effect the sloping or finishing of the sides of a railway
or similar cutting, the front part H2 of the triangular framing H, H', carrying the
chain of buckets for forming the cutting face is arranged to swivel vertically on
the centre of the lower guide roller N of the chain J, J', and to drop out at an
angle to the horizontal plane, equal to that of the slope to be given to cuttings
and embankments. A spare tie har or plate carried on the machine, may be fitted
on each side of the frame to connect the inclined upper part H¹, of the structure
to the swivelling front part H2; or a segment W fitted with a rack w, operated by
a pinion and gearing w³ carried on the standards I of the framing I, 11, may be
formed on the swivelling part of the frame to move it out to the desired angle.
A few additional links are then put into the chain J, J, to give it the requisite
extra length. A shoot H³ is formed at the lower edge of the framing H', and
a similar shoot H³ is fitted below the descending line of buckets to carry away any
loose material dropping from the buckets and to prevent such from falling among
the gearing, while also serving to stiffen the main framing.
The machine may be held up to the work in any convenient way, for example
as shown, by means of an arm y fitted in a central toothed rail Y laid on the
Bleepers.

page_text: Instead of fitting the improved arrangement of excavating machinery on the
swivelling platform described, it may be fitted on a platform having a traversing
movement both longitudinally and transversely, or any ordinary construction of
platform may be used, and when the machine is adapted for cutting the banks of
canals or rivers, a floating platform may be used.
Having now particularly described the nature of my said Invention, and in
what manner the same is to be performed, I declare that what I claim is,-
First. The arrangement or combination of parts forming the improved excavating
machine herein described and illustrated.
Second. An excavating machine carried on a movable bogie frame or on a
floating platform, and consisting of a swivelling framework carrying a chain of
buckets or buckets and picks, adapted to cut at various angles or degrees of
alope, and provided with a shoot or shoots arranged to swivel and deliver the
excavated material to either side of the machine, substantially as herein described
and illustrated.
Third. In an excavating machine, the swivelling frame D built up in sections
of lattice plates arranged to carry the upper framework H, I, substantially as
herein described and illustrated.
Fourth. The arrangement in an excavating machine of the delivery shoots, to
swivel on the carrying frame and discharge the excavated material into suitable
receptacles at either side of the machine, substantially as herein described and
illustrated.
Fifth. In an excavating machine, the mode herein described of carrying the
descending line of buckets on pulleys fitted clear of the sides of the buckets and
picks, substantially as herein described and illustrated.
In Witness Whereof, I the said Duncan Macdonald have hereunto set my hand
and seal, this Fifteenth day of March, in the year of our Lord One thousand eight
hundred and eighty-four.
Witness,
W. R. M. THOMSON,
Patent Agent Glasgow.
DUNCAN MACDONALD (L.S.)