DAcavators, and Controlling the same.
Year: 1897

page_text: Date of Application, 20th Apr.,
1007
Complete Specification Left, 28th Jan., 1898-Accepted, 26th Mar., 1898
Complete Specification Left, 28th Jan., 1898-Accepted, 26th Mar., 1898
111 DAcavators, and
Controlling the same.
ами
We, RAYMOND BOMFORD, BENJAMIN BOMFORD, and HARRY EVERSHED, trading
as R. and B. Bomford, of Pitchill, Evesham, in the County of Worcester, Engineers
and Contractors, do hereby declare the nature of this invention to be as follows:-
This invention relates to excavators or excavating scoops employed in making
excavations or removing dry earth, and in means for working and controlling
the same during both the filling and discharging the same, and consists in the
employment of a suitably shaped scoop, pivoted upon or hung from the after
part of a wheeled carriage and which fills as the carriage is drawn forward, with
the scoop, which is preferably of a triangular figure having its near side (which
constitutes the bottom of the excavator whilst the same is penetrating and filling)
coming at a lower plane than the surface of the earth over which the wheels of the
carriage are running, whilst the fore part of the said carriage has a bogie or
swivelling mounting and is steered by suitable gear. The scoop is controlled by
two sets of chains or cables worked by winding engines situated one at either
end of the line of traverse of the scoop.
In carrying out one form of our improvement, the scoop preferably consists
of a triangular sided sheet iron hopper or box, enclosed at back, top and bottom
and an open front or mouth, which, when the scoop is penetrating and filling, is
disposed at a convenient angle to the plane of the earth being excavated, whilst the
rest side or bottom of the scoop comes horizontal, with the back vertical and the
top inclined forwards. so that the side boundary edges of the scoop thus comprehend
the figure of a triangle. The front or cutting lip of the bottom has a slight upward
lead, whilst outstanding bars may project forwardly from the top edge of the open
mouth and form lifts for raising or elevating that edge of the scoop off the groun.
and preventing the mouth being fully closed during tipping, and to which the
tipping or back set of chains are attached.
This scoop, which may be varied in shape to suit the nature or character of the
soil to be excavated or operated upon, is horizontally slung or pivoted upon the after
end of a carriage consisting of a rectangular body frame, which may be terminated
at front by a triangular fore-carriage to which a widely separated pair of wheels
is bogied or vertically pivoted to turn about the said front part as a centre for
guiding. The pivot is made fast to the axle, whose wheels freely rotate upon the
axle arms, and works within the vertical bearing of a bracket, to which the nearly-
meeting sides of the triangular front are attached.
Angle pieces run from the inner sides of the frame to the middle of the front
of the body to support a bracket carrying a worm and tangent gear, with a chain
or equivalent pinion on the axis of the latter, the said worm being rotated by a
rod or axis working through suitable bearings and terminated by a hand or other
wheel or lever within easy reach of the man in charge of the excavator
seated upon one side of the carriage. The chain of the chain-pinion is continuous

page_text: and has its ends connected to the axle of the front wheels at separated points so
that by turning the worm the carriage guided either to the right or left. The
after part of the carriage is mounted upon a pair of wheels located on the two
opposite sides of the scoop, whose bottom, when penetrating and collecting the
earth is in a lower plane than the bottom of the wheel, the difference depending
upon the depth of cut to be made, which cut may be regulated, if necessary, by
raising and lowering the scoop relative to the wheels by suitable adjusting
mechanism.
The forward set of chains or cables are in two pairs, one for hauling or forward
traction and the other for bringing the scoop back to its acting position after
tipping. The hauling chains are connected at one end to the drum of a winding
engine, whilst the other ends are conveniently attached to the scoop, whilst the
other or "righting" set of chains are connected at one end to the engine and at
the other end to near the forward top edge of the scoop. These said righting
chains, pass between one or more pairs of stop pulleys mounted in brackets and
adapted for limiting or determining the various positions which the scoop is to
have whilst both travelling forwards in cutting and backwards prior to being
tipped, and backing again out of the tipped soil and travelling forwards to the
work before making another cut. This is principally effected by two sets of ball
stops on the chain, which may be released when required by a lever, actuated by
the man in charge of the implement.
The back gear consists of a pair of chains, worked from a second hauling engine,
these chains are fixed to brackets near the cutting edge of the scoop and pass
under a suitable retaining catch upon the back of the scoop which catch is made
to release the chain when it is required to tip.
now
Assuming that the earth to be excavated is loosened the excavator is run upon
the ground, the forward righting chain pulled to bring the scoop bottom to the
ground with the mouth presented to the earth. The forward hauling chain is
pulled, when the scoop makes a forward horizontal scoop into the earth and gathers
up the soil and when full, the chains upon the pulling side are slacked and paid out.
The tipping chains on the back are then tightened and the scoop is brought
into a position with the mouth uppermost. The tipping chains are
wound in until the scoop is brought to the place where the soil
is to be deposited. On reaching this, the retaining catch is released,
which allows the scoop to partly revolve and discharge its load. The scoop is
prevented from turning completely over by the second ball stop upon the righting
chain and during the time that it is being backed out from the tipped earth it is
prevented from resuming a cutting position by the first ball stop. The excavator
returns to the place where it is to be filled again, mouth uppermost and then the
ball stops are released by the attendant when the excavator is drawn into the
excavation and tilted further forward to its acting position, when the excavating
proceeds as before.
We wish it to be understood that we do not limit ourselves to the precise details
herein described, as the construction of the carriage and scoop and the means of
working and controlling the same may be varied without departing from the
nature of our invention and further, by making slight constructional modifications,
our invention may be applied to dredgers for use in clearing ponds, water-courses
and the like.
'
RAYMOND BOMFORD.
BENJAMIN
BOMFORD.
HARRY EVERSHED.
By Henry Skerrett,
Agent for Applicants,

page_text: Improvements in Excavators, and in Means for Working and
Controlling the same.
We, RAYMOND BOMFORD, BENJAMIN BOMFORD and HARRY EVERSHED, trading
as R. and B. Bomford, of Pitchill, Evesham, in the County of Worcester, Engineers
and Contractors, 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 or excavating scoops employed in making
excavations or removing dry earth, and in means for working and controlling
the same during both the filling and discharging the same, and consists in the
employment of a suitably shaped scoop, pivoted upon or hung from the after
part of a wheeled carriage and which fills as the carriage is drawn forward, with
the scoop, which is preferably of a triangular figure having its near side (which
constitutes the bottom of the excavator whilst the same is penetrating and filling)
coming at a lower plane than the surface of the earth over which the wheels of the
carriage are running, whilst the fore part of the said carriage has a bogie or
swivelling mounting and is steered by suitable gear. The scoop is controlled by
two sets of chains or cables worked by winding engines situated one at either
end of its line of traverse and is excentrically mounted in its carriage or frame
and is so constructed that whilst being filled, the wheels, which support or bear
the weight of 'the said scoop when travelling, are lifted above the level of the
ground to be excavated, but when full and after being turned over or with the
mouth coming uppermost a corner or angle of the scoop rests upon the ground and
thus prevents the machine from moving until the scoop has been tilted sufficiently
forward upon its said corner as a centre of motion to allow its wheels to come
again upon the ground and take the whole weight.
The machine is constructed and worked as we shall describe, referring to the
accompanying drawings.
Figure 1 is a diagramatic view, in longitudinal section of the excavator showing
the position of the scoop when filling in which the bottom of the said scoop is at
a lower plane than the wheels.
Figure 2 is a similar view to Figure 1, but shows the position of the scoop when
full and travelling to the place where the contents are to be deposited.
Figure 3 shows the position when emptying the scoop.
Figure 4 shows the position when empty, and travelling back to the point, where
the excavation is to be made.
Figure 5 represents a plan of the machine when in the position shown in
Figure 4.
Figure 6 is a cross section upon an enlarged scale of the framing of the machine,
taken upon the dotted line ¹, Figure 5, and showing the arrangements for steering
and controlling the scoop.
Figure 7 is a longitudinal section of the same.
Figures 8 and 9 are enlarged views of the "dog link" or releasing gear for
releasing the chains when the scoop is to be tipped.
The same letters of reference indicate corresponding parts in the several figures
of the drawings.
"
a,
The machine consists of a three sided box or scoop A, having the sides
b, c,
closed and the side d open, the front end of the bottom a, being provided with a
steel cutting plate e, adapted to penetrate or enter the soil to be excavated.
The scoop A is excentrically mounted upon pivots or centres of motion coming
rearwards of its centre of gravity and carried in a strong frame B, B, C, made

page_text: preferably of steel of E section and formed as shown in plan in Figure 5, triangular
in front and with the sides B, B, projecting backwards to embrace the scoop.
The front end of the frame is carried by an axle D, formed with a hole in the
centre, which fits loosely upon a stud g, fixed in a casting h, (which joins the two
sides B, B, of the main frame) the said stud projecting downwards for this purpose.
Upon the ends of the front axle D, two wheels K, K, revolve loosely, these
wheels serve to steer the machine which is accomplished by turning the axle upon
the stud g, by means of a pitch chain j. Figure 5, the ends of which are attached
to the axle, upon either side of the centre thereof, the pitch chain is driven by a
pinion Figure 7 keyed upon a spindle revolving in a casting m, which spindle
is revolved by the steerman, by means of the worm wheel n, and worm o, and
steerage hand-wheel p, the spindle q, upon which the hand-wheel is mounted,
driving the worm by means of an universal joint at r. A seat for the steersman
projects from the side of the frame at s.
The scoop (when travelling) is carried by two large and broad wheels E, E,
which revolve upon studs F, F, bolted to the sides of the scoop as shown. The ends
of the frame B, B, are also coupled to these studs F, F, between the wheels and the
scoop, in such a way that the studs are free to revolve within the holes in the
frame sides.
L, L, L, are wearing strips bolted to the bottom of the scoop to prevent wear
at that part should the bottom touch the ground owing to the wheels sinking in
soft places.
M, M, are stays to strengthen the main frame.
N, N, are rollers to keep the pulling chains from rubbing against the frame
when the scoop is tipping.
The machine is operated as follows:-
Assuming the scoop to be in the position shown in Figure 4 and travelling in
the direction of the arrow, a single forward hauling chain t, is fastened to the
centre of the back of the scoop at u, passes over the cutting plate e, through the
two stop pulleys v, vl, and is attached to the rope of the winding engine at w.
A ball is provided upon this chain at a, which is of such a diameter that when
the grooved pulleys v, vl, are pressed closely together as in Figures 4 and 7 it is
unable to pass between them.
The movement of the lower pulley ¹, downwards and away from the upper
pulley, so as to increase the distance between them is accomplished by mounting
it upon a pin 2, passing through holes in the ends of two bent levers y, y Figure 7.
These levers are carried by the pin z, in the frame a', and are moved by means of
a connecting rod 6', attached at one end to the levers and at the other end to a short
crank forged upon the end of a spindle c¹, mounted in bearings on the main
framing and capable of being revolved through one half of a revolution by a hand
lever d¹, which is placed upon the spindle c¹, at the opposite end to the crank
and close to the attendant's seat.
The upper pulley v, is incapable of vertical movement but revolves upon a bolt
passing through a supplementary frame a¹, and also through the ends of two
stays e, e, whose other ends are bolted to the main frame B, B, as seen in
Figure 5.
When it is desired to stop the ball from passing between the pulleys the crank
is turned to its lowest position, and the lower pulley, is thus locked in its
highest position, and prevents the ball from passing through the space between
the two said pulleys until the crank is reversed by the attendant and the pulley v¹,
lowered to make sufficient clearance for the ball to pass. When the ball is thus
stopped or checked (as in Figure 4) the machine is drawn forward by the pull
of the chain t, being transmitted to the ball, the part of the said chain t, between
the ball and the scoop, merely acting as a check to prevent the scoop from tipping
backwards, whilst it is prevented from tipping forwards, by two chains f¹, f
which are fastened to the scoop one on either side near the cutting plate e, these
two chains are coupled together to a single back pulling chain h¹, at g', the other

page_text: end of the said chain h¹, being fastened to the winding rope of the engine, which
although slack, when the machine is travelling in the direction of the arrow
(Figure 4) causes sufficient strain on the chain at g', to hold the scoop in the
position there shown.
The machine is allowed to remain in this position as shown in Figure 4 and
to travel in direction of arrow until it is desired to make an excavation or cut for
filling the scoop, when the ball is released, and the forward hauling chain t,
instantly pulls the scoop over into the position shown in Figure 1 thereby raising
the large wheels to a higher level than the bottom of the scoop and the latter is
thus able to enter the soil in the best position for filling.
There are two pulling chains ¹, i, attached to the same part of the scoop as
the chains f, f, and these, after passing through guide pulleys, suspended from
the front axle are both attached to the end of the winding rope.
These two chains ¹, i, and the ball chain t, take the whole strain when the
scoop is being filled as seen in Figures 1 and 5.
As soon as sufficient soil has entered the scoop the forward hauling winding
engine is stopped and the attendant couples the end of a short chain j¹, which
hangs from the chain h¹, to a dog link fixed to the back on the scoop at 4.
The other and back hauling engine now begins to pull and the scoop is tilted
or turned up by the chains f¹, f, into the upright position with its bottom resting
upon the ground and it is then by the continued pull of the chains f¹, f¹, turned
still further slightly forwards upon its bottom most corner with the ground as the
fulcrum until the supporting wheels come again upon the ground and take the
whole weight of the scoop and its contents. The scoop is then prevented from
turning further forward by the short check chain j¹, which now takes part of
the strain in hauling back the full scoop. Then so soon as the weight is borne
by the wheels, the machine is drawn along backwards by the hauling engine until
it reaches the point where it is desired to tip the spoil, when the attendant releases
the check chain j¹, by means of the dog link and as the whole strain now exerted
by the back hauling chains f¹, f, comes upon parts of the scoop rearwards of its
centres it turns completely over into the position shown in Figure 3 and discharges
the contents upon the ground. While the scoop is in this position (Figure 3) the
attendant turns the hand lever d¹, over and closes the pulleys v, v¹, and on the
first or forward hauling engine starting to pull again; the ball chain t, takes
the strain and pulls the scoop over until it again resumes the position shown in
Figure 4 and as soon as the ball is stopped by the pulleys v, v, the machine begins
to travel forward up to the point where it is required to make a further excavation
when the above described operation is repeated.
Figures 8 and 9 show one method of releasing the short check chain j¹, from the
scoop when it is desired to tip the same. 1, is a dog link mounted upon the scoop,
and in which a ring at the end of the chain is placed, the end of the dog link is then
depressed and held by a crank m¹, in the bar or spindle n¹, which is turned by a
lever o, upon its end, by means of a light chain or cord extending from the end
of the lever to within reach of the attendant's seat.
When it is desired to tip the scoop the chain or cord is pulled and this turns
the crank m¹ by means of the lever to the dotted position, thus releasing the end
of the dog link 7, which then turns up and allows the ring in the chain 1³, to
slip off.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what we
claim is:-
First. An excavator worked by hauling engines or machines, consisting of an
approximately triangular sided scoop, excentrically mounted on a frame or carriage
supported by wheels, substantially as and for the purposes described and set forth.
Secondly. An excavator worked by hauling engines or machines, consisting of

page_text: an excentrically mounted and approximately triangular sided scoop, so arranged
that when making an excavating cut the cutting side comes upon the ground in
a plane below the underside periphery of the wheels but when turned mouth upwards
after filling, a corner or part of the scoop rests upon the ground and prevents the
machine from moving until it has been turned sufficiently forward upon the said
corner or part as a centre, with the ground as the fulcrum, as to allow the wheels
to come again upon the ground with the scoop clear thereof, substantially as
described and set forth.
Thirdly. In an excavator worked by hauling engines or machines, the arrange-
.ment of the chains or cables of the tackle or gearing for hauling the machine
backwards and forwards, and for controlling the several positions of the scoop,
substantially as described and set forth.
Fourthly. An excavating machine, substantially as described with reference
to the accompanying drawings.
Dated this 24th day of Ionuo 120R
RAYMOND BOMFORD.
BENJAMIN BOMFORD.
HARRY EVERSHED.
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicants.