IMPROVEMENTS IN ROTARY SPADES OR DIGGING MACHINES POR TILLING LAND
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by John Thomas Brown Porter at the
Office of the Commissioners of Patents, with his Petition, on the
12th November 1867.
I, JOHN THOMAS BROWN PORTER, of Lincoln, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN ROTARY SPADES OR
DIGGING MACHINES POR TILLING LAND," to be as follows:-
The said Invention relates to improvements in the digging machine described
in the Specification of an Invention for which Letters Patent were granted to
Edwin Addison Phillips, bearing date the Tenth day of March, A.D. 1865,
No. 671. In the said machine a number of spading blades or tines are
carried around fixed cams, and forced thereby into the ground as the machine
is drawn forward, and the said blades are folded up clear of the ground
to allow the machine to be conveniently removed from one field or locality to
another.
The object of my present improvements is to obviate the necessity of this
folding up of the blades or tines, and the said improvements consists chiefly
in the combination with the said machine of a pair of wheels whereon the
machine is supported, with the blades clear of the ground in travelling from
place to place.
The said improvements also consist in the devices employed for adjusting the
machine into position for either working or travelling. The travelling wheels
are carried by two levers whose fulcrums are supported upon the main shaft
or other convenient portion of the machine. The short arm of each of these
levers is preferably formed with strong iron jaws between which the wheels

page_text: are fitted to turn freely upon pins or studs fixed in the said jaws. The long
arm of the said levers may be formed of wood or iron and fitted into a socket
cast upon the short arm. A chain or rope is connected to the extremity of
the short arm of each lever or to a bracket or projecting rod attached to each
of the said arms. The other end of each of these chains is attached to a drum
or barrel, one of which is fixed upon each end of a shaft or spindle which is
carried in suitable bearings at the front of the machine. Other barrels of
larger diameter are also fixed on the said shaft, to each of which another rope
or chain is connected whose other end is secured to the extremity of the long
arm of the levers. The chains are so arranged and attached to the barrels
that those connected to one arm are wound upon their barrels as those
connected to the other arm are unwound. The shaft is turned on its axis by
means of a handle wheel fixed on the upper end of a vertical or other shaft
geared in connection with the barrel shaft, or by other convenient and suitable
When it is desired to remove the machine the shaft is turned in the
proper direction to wind the chains connected to the long arm of the levers upon
the barrels and bring the said arms into a horizontal position. The short arm
which is arranged at right angles, or nearly so to the long arm is thus turned
downward, bringing the wheels to the ground and raising the machine with the
forks clear of the same. To adjust the machine for working the barrel shaft is
turned in the opposite direction, winding the chains of the short arms upon their
barrels and turning the said arms upward. The travelling wheels being thus
raised from the ground the machine is then lowered and is ready for working.
When the machine is in motion the lifting is effected by lowering the
travelling wheels which act as a fulcrum whereon the machine is raised
as it is drawn forward.