Year: 1886

page_text: We JAMES HOWARD, Engineer, and HENRY WILLIAM GIBBS, Engineer, both of
Bedford in the County of Bedford 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 :-
The chief object of this invention is to increase the durability of Ploughs of the
type in which the ordinary coulter is dispensed with by providing for the ready
reversal of that part of the implement which effects the vertical cut.
In certain ploughs of the Swedish and Anglo-American types, the shares are
made with or have fitted to them a cutting edge or shin-piece upon the landside,
which cutting edge or shin-piece performs the same work as the separate coulter
upon other ploughs.
Although the advantage of this cutting edge or shin-piece over the ordinary
separate coulter is considerable under certain circumstances; the cost of the
combined share and shin piece is great, and the cost of maintaining the efficiency of
the plough is enhanced.-This is due to the fact that the lower portion of the
cutting edge or shin-piece becomes blunted or worn out before any appreciable
wear has taken place in the upper portion thereof.
The main object of our present invention is to obviate this defect, and in
carrying out our invention, we provide a separate and reversible shin-piece of steel,
chilled cast iron, or other suitable material, so that when the front cutting edge or
the lower end next the share becomes worn or blunted, the unworn or less worn
portion of the shin piece may be brought into use.
In the accompanying drawings,
Fig. 1 shews in side elevation,
Fig. 2 in back elevation, and
=
3
Fig. 3 in plan view, one form of reversible shin piece detached from the plough.
Figs. 4 and 5 shew the reversible shin piece applied to a plough of an Anglo-
יד

page_text: b
as will serve to illustrate the application of our invention, and Fig. 5 a similar
view of the furrow side of the plough.
In the general views, A is the reversible cutting edge or shin piece, made fast to
the turn furrow plate, or so-called mould board B.
C is a portion of the frame of the plough, and D is the land side plate, the
parts B and D being secured to the plough frame in the usual manner.
E is the share secured to the nose of the plough frame, and fitted to the
reversible shin piece A in such a manner as to ensure that the land side edge of
the share shall be in the same plane with the land side face of the reversible shin
piece A.
By referring to Fig. 3, it will be seen that the fore part of the shin piece is of a
V section, and that its back part is rebated to about one third of its maximum
thickness. The two rebates thus formed are intended to receive respectively the
front edges of the mould board and landside plate, and thereby to form a shield or
protection to those edges against frictional contact with the soil.
The thin back portion of the shin piece A is extended rearwards to form two
lugs for the reception of screw bolts, by which the shin piece is secured in its
desired position.
The opposite ends of the shin piece A are chamfered off in opposite directions, as
shewn in the detached view Fig. 2, to provide for the close fitting of the same to
the share, as indicated by the dotted lines in Figs. 2 and 3, and the lugs are bent
out of line, so that the one shall stand parallel to one inclined side, and the other
to the opposite inclined side of the shin piece.
Thus, the lowermost lug will lie snugly against the landside plate (whichever
lug is undermost), as is indicated by the dotted lines in Fig. 3, which represent
the plate D.
By reason of the lower end of the shin piece engaging with the share, as
illustrated at Figs. 4 and 5, it will not be possible for the shin piece, although
attached to the mould board by one bolt only, to lift or get out of place
during use.
1
In general, the wear of the shin piece A will not extend above one half its
length, but when this wear has become considerable, and it is found necessary to
restore the efficiency of the plough, the attendant will have simply to withdraw
the coupling bolt, turn the shin piece end for end, and 'thus substitute the upper
and unworn cutting edge for the worn or blunted portion.
The re-insertion of the screw bolt will then secure the piece A, as before.
The reversible cutting piece admits of being modified in form whilst retaining
the efficiency of the implement.
Figs. 6 and 7 shew, in side and plan views, one such modification of the
detachable shin piece secured to the plough frame.
It. consists of a double-edged shin plate of steel, chilled cast iron, or other
suitable material, with a central hole for the reception of the bolt which connects
it to the plough frame.
I
The shin plate has a right and a left handed chamfer, which enables it to form a
smooth continuation of the land side plate, the forward end of that plate being
chamfered to correspond with the chamfer forming the back edge of the shin plate.
On the other side of the shin plate, the front chamfer similarly continues the line
of the mould board.
The shifting of the shin plate to present a fresh cutting edge is effected by
turning the back edge to the front.
Figs. 8 and 9 shew a further modification of the detachable shin piece. In this
instance the shin plate is chamfered at both edges, but on the same side of the
plate, and it is furnished with two bolt holes, as in the first example, for securing
it in position by a bolt and nut, attachment being in this case to the plough frame.
It is chamfered also at its ends to fit close against the hinder part of the share,
as in the first example.

page_text: For the purpose of shifting this shin plate, it is turned end to end without
changing the position of the land side, and it is for this reason that both edges of
the shin plate are chamfered on the same side.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
The application to ploughs of detachable and reversible shin pieces or plates for
giving the landside cut, as above set forth.