Improvements in Rotary Harrows.
Year: 1889

page_text: Date of Application, 6th Mar., 1889
Complete Specification Left, 29th Aug., 1889-Accepted, 5th Oct., 1889
PROVISIONAL SPECIFICATION.
Improvements in Rotary Harrows.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention a communication to me from
abroad by A. C. Brown, of Eugene City, in the County of Lane, State of Oregon,
United States of America to be as follows:-
This invention relates to a cheap and durable rotary harrow, so constructed that
each set of barrow teeth will be free to conform to any irregularity there may be in the
ground over which the harrow is being drawn; and the invention consists essentially
of a horizontal trussed wheel provided with harrow teeth and mounted to turn freely
upon a gudgeon turning in a bearing block mounted to tilt on a fore and aft hori-
zontal axis within a box forming part of the main frame of the harrow, all as
will be hereinafter more fully described. The invention also relates to the form of
the harrow teeth.
The harrow has preferably three wheels, two abreast and one in rear each journalled
in a block pivoted on set screws at the sides so that the blocks will be free to tilt
upon the screws, the range of motion of the blocks being limited by other set screws,
the two pairs of set screws being tapped into the four sides of an open box forming
part of the frame of the harrow.
From the hub of the wheel there is an upwardly-extending gudgeon which passes
through a central aperture in the bearing block, the gudgeon being slotted to receive
a cotter.
Just above the rear of each of the wheels there is mounted an antifriction-wheel
or roller, those above the two forward wheels being carried by a cross bar bolted to
the frame while the one above the rear wheel is carried by a rearwardly-extending
bar of the frame.
Each wheel is free to revolve on its axis independently of all of the other wheels,
and each wheel axis is free to tilt in a plane at right angles to the line of draft so
that the harrow teeth will conform with any irregularities in the ground, the friction
wheels preventing undue strain on the gudgeons in the line of draft.
Each wheel is constructed of an outer ring and of series of hexagonal inner frames
placed one within the other, the corners of each being bolted to the middle of the
side of the next outer one and the harrow teeth being clamped between the two at
the points where the bolts are situated. The innermost frame immediately around the
hub is a ring with outwardly cranked portions by which it is bolted to the sides of the
innermost hexagon frame.
In practice it is preferred to employ harrow teeth having concave bearing faces
against which the frames are bolted, below which concave bearing faces there are
shoulders which abut against the under edges of the frames of the wheel.
Dated this 6th dow of March 1980.

page_text: COMPLETE SPECIFICATION.
Improvements in Rotary Harrows.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex; Fellow of the Institute of Patent Agents,
do hereby declare the nature of this invention (a communication to me from abroad
by Asa. C. Brown of Eugene City, in the County of Laue, and State of Oregon,
United States of America, 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 a cheap and durable rotary harrow so constructed that
each set of harrow teeth will be free to conform to any irregularity there may be in
the ground over which the harrow is being drawn; and the invention consists
essentially of a horizontal trussed wheel provided with harrow teeth and mounted
to turn freely upon a gudgeon turning in a bearing block mounted to tilt on a fore
and aft horizontal axis within a box forming part of the main frame of the harrow,
all as will be hereinafter more fully described. The invention also relates to the form
of the harrow teeth.
Reference is to be had to the accompanying drawings forming part of this specifi-
cation, in which figure 1 is a plan view of a harrow constructed in accordance with
the terms of this invention Figure 2 is a side view of the same. Figure 3 is a
plan view of one of the harrow truss wheels, the gudgeon being shewn in section.
Figure 4 is a central sectional view of one of the truss wheels, a portion of the harrow
frame being shewn in connection therewith and in section. Figure 5 is a sectional
plan view illustrating the mounting of the harrow truss wheels, the view being taken
on line xx figure 4. Figure 6 is an enlarged sectional view of a portion of the
wheel and of one of the harrow teeth, the view illustrating a modified form of tooth,
Figure 7 is a perspective view of the head of a tooth similar to the one shewn in
figure 6, and figure 8 is a view of a portion of the rim of one of the truss wheels,
the antifriction wheel carried by the harrow frame against which the truss wheel at
times bears, being shewn in section. Similar figures and letters of reference indicate
corresponding parts in all the views.
In constructing a harrow, such as the one illustrated in the drawings above
referred to, I provide a frame 10 of any suitable form adapted to support boxes 11
and 12, the box 12 being to the rear of the boxes 11. To the forward end of the
frame 10 there is secured a draft eye 13. Within the boxes 11 and 12 there are mounted
blocks 14 which are pivoted on set screws 15, said set screws entering recesses in the
side faces of the blocks but being so adjusted that the blocks will be free to tilt
upon the screws, the range of motion of the blocks being limited by other set
screws 16. This construction is best shewn in figure 5. The harrow teeth 17 are
supported by truss wheels A, said wheels being made up of an outer rim 18 to
which there is bolted a strip 19 by bolts 20 which pass through holes in the heads of
the teeth; and to the strip 19 there is bolted a strip 21 by bolts 22 which pass
through the heads of an inner set of harrow teeth and through the strip 19 at points
midway between the bolts 20. To the hub 30 there is bolted a strip 31 formed with
outwardly-extending loops and to these loops there is connected a strip 34, a set of
harrow teeth being interposed and supported by the connecting bolts 33. The strip 34
may be connected to the strip 21, as at 34, harrow teeth being arranged as in the
other connections, or other strips and sets of harrow teeth may be employed, as will
be readily understood. From the hub 30 there is an upwardly-extending gudgeon 35
which passes through a central aperture in the bearing block 14, the gudgeon being
slotted to receive a cotter 36 which prevents all accidental displacement of the parts.
Just above the rear of each of the wheels A there is mounted an anti-friction wheel or
roller 40, those above the two forward wheels A being carried by a cross-bar 41
that is bolted to the frame 10 while the one above the rear wheel is carried by a
rearwardly extending bar 42 supported by a socket 43 that extends to the rear from
the box 12..

page_text: Each wheel is free to revolve on its axis independently of all of the other wheels and
each wheel axis is free to tilt on a plane at right angles to the line of draft, so that
the harrow teeth will conform with any irregularities in the ground, the friction
wheels 40 preventing undue strain on the gudgeons in the line of draft.
In practice, I prefer to employ harrow teeth of the form shewn in figures 6 and 7,
that is with concave bearing faces c d below which concave bearing faces there are
shoulders e which abut against the under edges of the frames of the wheel.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is;
1. In a rotary harrow, the combination with a supporting frame, of tilting blocks
carried by the frame, wheels carrying harrow-teeth and formed with gudgeons adapted
to enter apertures in the tilting blocks, substantially as described.
2. The combination, with a main supporting frame carrying anti-friction rollers, of
trussed harrow-teeth-carrying wheels A, gudgeons extending from the wheels A,
blocks through which the gudgeons pass, and a pivotal connection between the blocks
and the main supporting frame, substantially as described.
3. In a rotary harrow, the combination with a box 11, of a block formed with a
central aperture, set screws by which said block is supported within the box, liniit
screws arranged in connection with the block, and a tooth carrying wheel formed
with a gudgeon which enters the aperture in the block, substantially as described.
4. A harrow tooth formed with a head having concave faces, as c and d, and
shoulders, as e, substantially as described.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.