IMPROVEMENTS IN MACHINERY OR APPARATUS FOR LETTERS
Year: 1883

page_text: LETTERS PATENT to Edward Cobham, of Stevenage, in the County of Herts
"
for an Invention of IMPROVEMENTS IN MACHINERY OR APPARATUS FOR
LETTERS PATENT to Edward Cobham, of Stevenage, in the County of Herts
for an Invention of IMPROVEMENTS IN MACHINERY OR APPARATUS FOR
"
DIGGING OR CULTIVATING LAND
PROVISIONAL SPECIFICATION left by the said Edward Cobham at the
Office of the Commissioners of Patents on the 30th January 1883.
EDWARD COBHAM, of Stevenage, in the County of Herts " IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR DIGGING OR CULTIVATING LAND
"
This invention relates to machinery or apparatus used for digging or cultivating
land by means of forks or tines actuated by steam power, and it has for its object
improvements in the method of constructing and arranging the parts of such
machinery or apparatus, so that the depth at which the process of digging or
cultivating is effected in the ground is maintained sufficiently regular and even,
although the surface of the ground passed over may be irregular and uneven,
whilst the pressure upon the ground by the digging machinery passing over it is
materially reduced.
In order to put my invention in operation I take a light steam traction Engine,
of any of the ordinary well known kinds, the end of the fore carriage of the
Engine being preferably constructed so that the end of the boiler may be raised or
lowered as desired, the crown of the firebox being in this way kept covered with
water when the Engine is going down hill, and priming being prevented when the
Engine is going up hill.
A carriage supported upon low wheels or rollers is attached to the main axle of
the traction Engine by which it is drawn forward.
Two of these wheels or rollers are arranged behind the axle and at each side of
the Engine, and one or two of them in front. At the outer end of the digger
carriage are arranged the digging or cultivating forks or implements actuated by
a crank shaft operated by the Engine in the usual well-understood manner.
The shafts or frames supporting the wheels or rollers are capable of being readily
CD

page_text: lengthened or shortened so as to determine the depth to which the digging
implements enter the ground.
So long as the weight of the digger carriage is sufficient to force the tines, forks,
or digging implements into the ground those wheels or rollers which are situated
close to them will follow the surface of the land and so regulate the depth to
which the implements operate; but if, through the hardness of the ground, such
weight should be insufficient the wheel or wheels at the other side of the axle
will come into operation and by their leverage upon the frame will throw the
whole weight of the apparatus upon the digger carriage and thus compel the
digging implements to enter the ground as desired.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edward Cobham in the Great Seal Patent Office on the 30th July
1883.
EDWARD COBHAM, of Stevenage, in the County of Herts "IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR DIGGING OR CULTIVATING LAND
"
My invention relates to machinery or apparatus used for digging or cultivating
land by means of forks or tines actuated by steam power, and it has for its object
improvements in the method of constructing and arranging the parts of such
machinery or apparatus, so that the depth at which the process of digging or
cultivating is effected in the ground is maintained sufficiently regular and uniform,
although the surface of the ground passed over may be more or less irregular and
uneven, whilst the pressure upon the ground by the digging machinery passing
over it is materially reduced.
In order to put my invention in operation I take a light steam traction Engine,
of any of the ordinary well known kinds, the end of the fore carriage of the
Engine being preferably constructed so that the end of the boiler may be raised or
lowered as desired, the crown of the firebox being in this way kept covered with
water when the Engine is going down hill, and priming being prevented when
the Engine is going up hill.
A carriage supported upon low wheels or rollers is arranged so that the front
end of its framing which is made sufficiently strong turns upon the main axle of
the traction Engine, by which it is drawn forward. Two of these wheels or rollers
are arranged behind the axle and one or more of them in front at such distance
apart in plan that the whole of the ground passed over by the machine is covered
by them.
At the outer or back end of the digger carriage are arranged the digging or
cultivating forks or implements actuated by a crank shaft operated by the Engine
by means of toothed gear carried in the supporting frame already described in the
usual well understood manner. The shafts or frames supporting the wheels or
rollers may be made capable of being readily lengthened or shortened so as to
determine the depth to which the digging implements enter the ground. So long
as the weight of the digger carriage is sufficient to force the tines, forks, or digging
implements into the ground those wheels or rollers which are situated close to
them will follow the surface of the land and so regulate the depth to which the
implements operate; but if, through the hardness of the ground, such weight
should be insufficient the wheel or wheels at the other side of the axle will come
into operation and by their leverage upon the frame will throw the whole weight
of the apparatus upon the digging implements and thus compel them to enter the
ground as desired.
I arrange the front supporting rollers so that their vertical position can be
altered as desired; and when it is required that the machine should travel on
ordinary roads these rollers are raised sufficiently to clear the road, and the entire
frame with the digging implements can be lifted sufficiently round the main
axle as a centre and can be retained in its position until it is required that it should
be again lowered for work.
The accompanying drawing is in illustration of my invention, and represents a
side view of the entire apparatus. a is the boiler carrying in the usual way an
Engine and supported upon front steering wheels at c and main driving wheels
at d, the latter being actuated by means of toothed wheels and pinions of properly
proportioned dimensions shewn in dotted lines at e¹. The frame carrying the

page_text: digging implements turns upon the axle g of the wheels d and is fitted with a
transverse shaft and toothed wheels and pinions h driven by the wheel e', and
actuating the transverse cranked shaft h¹ which drives in the usual well-known way
the digging tines or implements i, i, i, the movement of the upper ends of which
are regulated by the links k turning on the centre l. A clutch-box actuated by a
handle is shewn at k by which the gear can be connected or disconnected.
Supporting wheels m, the height of which may be made adjustable, are arranged
upon the frame fin front of the tines i, and the frame f carried forward and
down in front of the axle g its lower end carrying strong bearings in which the
supporting wheels n turn, these bearings being capable of being raised or lowered
as desired, as shewn in dotted lines at n¹. An adjustable link or shackle is shewn
at o by which the frame f and digging implements i can be raised from the
ground, when the wheels n have been first lifted.
The action of the machine is as follows:-The wheels m being adjusted at the
proper height for the depth of digging required, and the wheels n being lowered
so as to touch the ground, the entire machine is propelled forward by means of the
Engine actuating the wheels d and at the same time setting 'the digging implements
or tines i, i, i, in operation.
Should the weight of the frame f and its gear be insufficient, from 'the hardness
or irregularity of surface of the ground, to ensure the proper action of the digging
tines, the wheels n come into operation and by their leverage throw the whole
weight of the apparatus upon the tines and force them into the ground.
When the machine is to travel on ordinary roads, the wheels n are raised, and
the entire frame ƒ and implements i, i, i, are raised from the ground by the
shackle o.
Having now described my invention and the manner in which it is 'to be
performed, I claim :-
The combination of the Engine, driving wheels and gear, and suspended frame
and digging apparatus, with the supporting wheels or rollers arranged close to the
digging implements, and the wheels or rollers upon the frame in front of
driving wheel, all substantially as and for the purpose described and shewn in
the drawing.
Also, in combination with such apparatus arranged and operating as described,
the method of raising the front wheels or rollers from the ground and lifting the
entire frame and digging apparatus, for the purpose of travelling upon ordinary
roads, substantially as described and shewn in the drawing.
In witness whereof, I, the said Edward Cobham have hereunto set my hand and
seal this 30th day of July in the year of our Lord 1883.
n COPITA BE