IMPROVEMENTS IN PLOUGHS
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Thomas Corbett at the Office
of the Commissioners of Patents, with his Petition, on the 19th
January 1871.
I, THOMAS CORBETT, of Shrewsbury, in the County of Salop, Agri-
cultural Implement Manufacturer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN PLOUGHS," to be as follows :-
My Invention consists of the construction and arrangements of parts
herein-after described for supporting and adjusting the wheels of ploughs
and for turning the ploughs at the headlands.
My improvements are especially applicable to double furrow plougns,
but are also applicable to other ploughs.
I will describe my Invention as applied to double furrow ploughs.
In supporting and adjusting the wheels of ploughs according to my
Invention instead of fixing the wheel stems directly to the double beam
as usual I fix at the front of the plough where the wheels are to be
supported a bed plate, the said bed plate fitting between the inner sides
of the double beam, and being fixed thereto by screw bolts and nuts
Made in one piece with the bed plate by the casting process are two

page_text: eyes or sockets, through which eyes or sockets horizontal bars pass for
supporting the vertical stems of the wheels. The said horizontal bars have
at their outer ends claws or holders, between which claws or holders
sockets carrying the vertical stems of the wheels are situated. By means
of screw pins passing through the eyes or sockets on the bed plate the
horizontal bars may be moved in the said sockets, and fixed nearer to or
further from the beams of the plough, and by means of the sockets in the
holders at the ends of the horizontal bars the vertical height of the
wheels may be adjusted. The wheels are thus capable both of a
horizontal and vertical adjustment on the plough.
In applying this part of my Invention to single furrow ploughs I
make the bed plate carrying the eyes or sockets embrace the single
beam of the plough and fix it by screw bolts.
I construct and arrange the parts of ploughs for turning the said
ploughs at the headlands in the following manner :-I use a bed plate
fixed between the double beam of the plough, as before described,
excepting that the said bed plate is without eyes or sockets. Upon the
upper face of this bed plate a rotating socket plate is pivotted. The
furrow wheel of the plough is supported and adjusted in a socket
in the said rotating plate in the manner herein-before described, but
the land wheel is constructed and worked as follows:-The said land
wheel is connected to the lower end of a cranked arm, the said arm
turning in bearings made in the rotating socket plate. By means of a
lever fixed to the horizontal part of the cranked arm the said arm may
either be placed obliquely or vertically. When the said arm' is placed
obliquely the land wheel connected with it is raised above the level of
the furrow wheel, and the plough is in position for work, the said
furrow wheel running in the furrow, and the land wheel running upon
the land above the furrow. The cranked arm carrying the land wheel is
fixed in the position described by means of a pin or stud on the lever,
by which the said wheel is moved engaging with a notched quadrant
plate secured to the rotating socket plate. By means of this quadrant
plate and lever the height of the land wheel may be adjusted. When
the cranked arm is situated vertically, which is effected by depressing
the lever, the land wheel is made to descend, and the said land wheel is
now situated at the same level as that of the furrow wheel, and the
plough may be turned upon the said wheels. The turning of the land
and furrow wheels is effected as follows:-The rotating socket plate:

page_text: carrying the supports of the two wheels is kept stationary during the
working of the plough by means of a rod or lever passing from the said
socket plate to a cross bar at the tail of the plough, the said rod or lever
being fixed by engaging with notches in the said cross bar. When the
land wheel lever is depressed to bring the said wheel into position for
turning the plough the said lever engages by means of a spring snap
fastening with a hook or projections on the rod or lever of the rotating
socket plate, and the two levers are thereby locked together, and by
grasping the said levers the rotating socket plate can be turned in the
required direction upon the bed plate, and a corresponding motion given
to the wheels, and the plough when it arrives at the headland can thus
be turned with great facility. A pair of land wheels may be employed.
In this case I connect a second wheel to the land wheel already
described by means of links, one of the said links turning on a centre
on the beam of the plough..