Art of and Means for Reproducing the Working Edges of Implements.
Year: 1895

page_text: Date of Application, 23rd May, 1895-Accepted, 6th July, 1895
COMPLETE SPECIFICATION.
Art of and Means for Reproducing the Working Edges of
Implements.
I, CHARLES LA Dow, of Thurlow Terrace, Albany, in the County of Albany
and State of New York, U.S.A., Mechanic, 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:-
This invention comprises a novel construction of agricultural and other implements,
and an art or mode of maintaining or renewing the working edges, points, or
members thereof.
The implements, whatever be their form or character in other respects, comprise
a main body portion, as a blade, tooth, or the like, provided with an exposed
primary or initial working edge, point, or member, a following substitute working
edge, point, or member, and an intervening weakening element.
A characteristic feature of the construction is the outlining, in one and the same
implement, blade, or part of a rudimentary substitute cutter, one or more, which is
normally protected by the outermost or initial cutter or member, but which may
be exposed and brought into use as the active working portion, through the wearing
away or removal of such outer cutter or member.
The outlining of the substitute cutters may be by means of grooves, by alternate
elevations and depressions, or by any other suitable weakening element, and any of
these weakening elements may be variously arranged as to direction, form, and
arrangement, as suggested or required by the contemplated use.
Within these general limits, the structure is susceptible of numerous variations,
some of which will be hereinafter explained.
The art of maintaining or renewing the working portions of an implement
comprises essentially two steps or operations, first, the formation of an initial
working edge, point, or member and a substitute working edge, point, or member
in one and the same blade, tooth or implement, with an intervening weakening
element; and second, wearing away the initial member and thereby exposing the
substitute member.
As further refinements of the art thus broadly stated, I may also, by properly
fashioning the substitute cutters, determine the relative rates of edge and face wear,
and the rate of wear at different points in the edge and in the face, thereby better
ensuring the preservation of any predetermined outline, and the successive presenta-
tion or exposure of the substitute working members In practice, it is preferred to
wear away the members successively, by contact with the substance operated upon,
though the invention is not restricted thereto.
The invention may be best explained in connection with the accompanying
drawings, wherein,-
Figure 1 is a top plan or face view of a plow point embodying my invention;
Fig. 2, a transverse sectional view of the same, on the line g-g of Fig. 1 ;
Fig. 3, a similar section, on the line -h of Fig. 1;
Fig. 4, a rear face view, and
Fig. 5, a longitudinal sectional view of the point of a spring harrow tooth;
Fig. 6, a rear face view, and
Fig. 7, a longitudinal sectional view of a cultivator blade or shovel embodying
my invention;
Fig. 8, a face view of a blade or shovel in which the cutters are outlined by
perforations or incisions;

page_text: Fig. 10, a sectional view of a disk suitable for cultivators, harrows, and the like
machines, showing the application of my invention thereto;
Fig. 11, an enlargement of a portion of Fig. 10;
Figs. 12, 13 and 14, sectional views illustrating implements embodying the
invention in varying forms;
Figs. 15 and 16, respectively, face and edge views of a trailing coulter, suitable
for use in connection with harrows;
Fig. 17, an end view of the same;
Fig. 18, a rear face view of the point or blade of a spring harrow tooth or
equivalent implement, illustrating the manner in which the implement wears away
and drops off the worn-out portions, thus exposing and completing the rudimentary
cutter following;
Fig. 19, a longitudinal sectional view of the same, indicating the manner in which
the implement wears away to expose and perfect successive substitute members;
Fig. 20 is a cross section, on the line ii of Fig. 18;
Fig. 21, a sectional view of a plow point such as is shown in Figs. 21 and 22,
illustrating the manner in which it wears away and produces successive cutting
edges;
Figs. 22 and 224, rear and front face views of a harrow tooth of another form,
containing the invention;
Fig. 23, a diagrammatic view illustrating the mode of using a disk, provided
with the substitute working members, and the disk being sectioned and viewed from
above;
Fig. 24, a diagrammatic illustration of a spring harrow tooth in use, showing the
nature and effect of wear which takes place in such use;
Fig. 25, a perspective view of the point of such a tooth, showing the nature of
the face wear thereof;
Fig. 26, a face view of such a tooth, indicating the depth of penetration ;
Figs. 27 and 28, rear face views of implements, respectively, showing the
rudimentary working members arranged in straight lines, diagonal to the line of
penetration, and in curved lines.
Refering first to Figs. 1, 2, 3, and 21, it will be seen that the implement, in this
case a plow point, is formed with a beveled outer edge or marginal cutter, a,
behind or within which are outlined substitute working members or cutters a¹, a².
The outlining of the substitute edges is here effected by producing in the upper
face of the implement a series of parallel grooves, depressions, or lines of relative
weakness,,,, as shown in said Figures 1, 2, 3 and 21. By making the grooves
or depressions of increasing depth toward the outer cutting boundaries of the
implement, the substitute working members a¹, a², are made of approximately the
same form in cross section as the initial cutter or member a.
The body of the implement, or that portion intervening between the bottoms of
the grooves and the opposite face of the implement, is advisably made of increasing
thickness from the outer cutting boundaries inward, so that sufficient strength shall
be afforded for the initial and substitute cutters, not only in the first instance but
as the body wears away.
Referring now to Figure 21, y, indicates the line of abrasion or wear of the upper
face. It will readily be understood that when said implement moves forward
through the soil in the direction indicated by the arrow, the extreme forward edge
will receive the full impact incident to penetration, while the upper face will be
subjected to a grinding or abrading action due to the working of the soil over it.
This tends to wear away the upper face quite rapidly, particularly at and
immediately adjacent to the forward edge, and decreasing thence inward.
As a
consequence, the outermost cutting member or rib a, is gradually worn away, at
the edge and on the upper face, maintaining all the time a thin and sharp cutting
edge.
There is, of course, a certain amount of wear on the under face of the implement,

page_text: but this is relatively slight, owing to the smoothness of the face, and to the fact
that it lies directly in the plane of advance, and not at an angle thereto, as does the
inclined upper face.
It may sometimes happen that a working edge a, will wear unevenly, or become
nicked or broken, so that it will not work satisfactorily, in which case the outer
rib, cutter, or member may be removed through the use of a cold chisel, as indicated
in Fig. 1, or it may be broken off with pincers or other suitable tool,-the groove b
or b, facilitating the removal, and also determining the line of separation, and form
of the substitute.
As the soil works over all substitute or rudimentary cutters or working
members a, a, &c., whenever the implement is in use, it will be seen that
the cutters or members further inward receive a greater aggregate wear than
those nearer the boundaries or working edges. It is therefore desirable to make
the successive grooves b, b¹, &c., of increasing depth, progressively inward from
the edge, as illustrated in Fig. 21, so that, by the time a given member or
cutter a, a, &c., is exposed and made the active cutter, it shall have been reduced
to approximately the same thickness as the initial cutter first possessed.
The principle thus explained, or the mode of reproducing the cutting or
working edge and maintaining its desired form and dimensions, at least
approximately, is involved more or less fully in all the embodiments of my
invention here illustrated.
Next referring to Figs. 4 and 5, it will be observed that the rudimentary or
substitute cutters are formed in the rear instead of the front face of the implement,
speaking with reference to the direction of advance. In this case, the face of the
implement, (which may be a spring harrow tooth, a cultivator blade, or shovel, or the
like,) is presented much more squarely to the soil than is the plow point, and it is
important that the front face be smooth and free from obstructions or irregularities
of any kind. In this, as in the plow point, the extreme point of the blade or shovel
receives the greatest wear, as it receives the full impact of the work and opens the
way for the body of the tool. The entire outer edge of the point receives greater
wear than the portion inward from such edge, the wear growing gradually less and
less toward the medial line of the blade, and upward from the point, as is well
illustrated in Figs. 24 and 25. This peculiarity of wear causes a constant thinning
of the point, the abrasion being almost wholly on the front face and forward edge
of the blade. The line x-x, Fig. 24, indicates the line or direction of wear from
front to rear at the exposed edge, and the line y-y indicates the facewise wear,
the resultant form being clearly shown.
:
As the face and point thus wear away, the initial cutter a, gradually disappears,
and a second cutter a', is exposed and brought into active operation, as indicated
in Fig. 24 or the web or body becomes so thinned and the initial cutter so reduced
that the remnant of said cutter breaks or drops off. If desired, the remnant may
be broken off by a sharp blow from a hammer, or by pincers or other suitable tool,
as indicated in Fig. 27.
Figs. 6 and 7 illustrate the same features of construction described in connection
with Figs. 1 to 5, inclusive, which, therefore, require no further explanation.
It will be seen that if there be a considerable number of the weakening elements,
whether grooves, depressions, or other, the implement might be unduly weakened
and rendered liable to break off at a point remote from the then working member.
This result is quite effectually guarded against by the oblique, diagonal, or curved
arrangement of the substitute cutters or working members, as in Figs. 4, 6, 18, 22,
26, 27 and 28.
Under all these forms the rudimentary or substitute working members mutually
support and sustain each other, crossing the natural line of fracture.
This is well illustrated in Figs. 18 and 20, the latter being a section on the
line - of Fig. 18, and showing how the rudimentary members a, a', a², cross
said line and mutually brace the implement against facewise pressure or strains.

page_text: The substitute cutters or working members, it will be observed, point in the same
direction, so as to immediately follow each other as operative substitutes.
In some cases, the substitute cutter projects into the initial cutter and braces it,
as above explained. When I speak of the cutters as being arranged diagonally I
mean diagonally with reference to the line of draft, or diagonally with reference to
the direction of penetration.
In some implements, this diagonal or oblique arrangement is impracticable or
undesirable. In such cases, and in others also if desired, strengthening ties c, may
be employed, extending from one to another of the cutters or working members, as
in Figs. and 6. The form and arrangement of these ties may be varied
considerably. They may be formed integrally with the implement, or applied
thereto, as found expedient in any given case.
In Fig. 8, I have represented the implement as formed with a series of
rudimentary cutters or working members a¹, a², &c., outlined by slits or
incisions, 63, &c., which may extend into or entirely through the body of the
implement, and which form or produce weakening elements between the cutters.
Figs. 9. 10 and 11 illustrate the application of the invention to a circular or
disk-shaped implement, detailed explanation of which is deemed unnecessary in
view of what has been said.
Figs. 12, 13 and 14 merely illustrate a few of the many different forms that the
elevations and depressions may take in practice.
Figs. 15, 16 and 17 differ from others in that they illustrate the alternate
depressions and elevations, or in other words, the rudimentary or substitute
working members and intervening weakening elements as formed in both faces of
the implement instead of in one only. The implement selected for illustration is a
trailing coulter, and the principle of construction and operation is the same as
already explained.
Figs. 18, 19, 20 and 21 have been already sufficiently described.
Figs. 22 and 224 illustrate the application of the invention to a pointed harrow
tooth of V-section. In this the successive working members a, a', &c., and
intervening depressions or weakening elements b, b', &c., are essentially the same
as in Figs. 4, 5, 6, 7, 18 and 19, being formed in the rear face of the implement.
The remaining figures have been sufficiently explained, Figs. 27 and 28 merely
showing different forms that the substitute working members may take, with a view
to bracing or strengthening the implement against working strains.
The implements may be made of iron, steel or other suitable materials, and may
be cast, forged, or otherwise produced. The working members, both initial and
substitute, may be produced in the implements by casting, forging, cutting,
grinding or otherwise, but are to be present therein before it is applied to use,
the natural wear due to contact with the material in or upon which it operates
serving or assisting to remove one and expose another cutter as renewal becomes
necessary.
The construction set forth and explained enables me to prepare not only the
initial working edges, but the substitute working members as well, for efficient
work and prolonged wear, whether one or another material be selected, or one or
another mode of manufacture be resorted to. When the implements are cast,
whether of iron or steel, or of other suitable material, the thinner portions will, if
permitted, cool more rapidly than others, and chill or harden, so that those portions
which are to constitute the entering or dividing edges may be made harder than
other portions. So, too, if forged or struck up in a die or drop press, those portions
which are depressed most, and which constitute the thinner edges of the initial and
substitute working members, may, particularly in the case of cold forging, be
rendered more dense than the thicker portions, by reason of the greater
compression to which they are subjected.
If the weakening elements be formed by grinding or cutting away the metal, or
making incisions therein, this will naturally be done while the metal is in a

page_text: relatively soft condition or before tempering. In subsequently tempering the
implement, those portions which are most reduced and which are subsequently to
constitute the entering edges of the initial and substitute cutters or working
members, may be more readily brought to a proper tempering heat, and more quickly
cooled, hence it is entirely feasible to prepare the entering edges of the substitute
as well as the initial cutters or working members to perform their work in a most
efficient manner, even though they be not entirely completed in the original
production of the implement.
My invention comprehend this feature, but is in no sense or degree dependent
thereon.
In the foregoing description I have set forth my invention as embodied in
agricultural implements, and have illustrated and described such forms as seem
best calculated to elucidate the general plan involved. It is, however, to be
understood that the invention is not restricted to agricultural implements, but is
applicable generally to any and all implements and articles requiring the
maintenance, renewal or sharpening of a working point, end, edge, or member.
While the means shown and described for carrying out my invention are simple
and efficient, I do not by any means limit myself thereto.
Having now.rticularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is-
1. The art of renewing the working edge of an implement, which consists in
first forming in a single blade, tooth, or cutter, substitute working edges pointing
in the same direction, and then wearing away the initial edge to expose a
substitute.
2. The art of reproducing the cutting portion of an implement, which consists
in causing a wearing away of the initial cutter by contact with the substance
operated upon, to expose a previously outlined substitute cutter.
3. The art of reproducing the cutting portion of an implement, which consists
in wearing away the initial entter, dropping off the remnant thereof, and bringing
into operation a previously outlined substitute cutter.
4. The art of sharpening an implement, which consists in first forming a
weakening element in one face thereof to outline and prepare a substitute cutter
integral with the implement; then wearing away the initial cutter to expose the
substitute cutter.
5. The art of renewing the working edge of an implement formed of a single
piece of metal, which consists in the following steps performed in the order stated:
first, forming alternate elevations and depressions upon and in the surface of the
implement, thereby outlining substitute cutters; and second, subjecting the
implement to a wearing action from the outer edge inward.
6. The art of renewing the working edge of an implement, which consists in
forming therein a depression trending in the general direction of the desired outline
of the working edge, and increasing in depth towards such edge, and secondly,
subjecting the implement so prepared to a facewise wearing from the outer edge
inward; whereby its material is worn along the line of the depression and the
thin body previously constituting the bottom of such depression is made to form a
new working edge.
7. An implement comprising substitute cutters or working edges definitely
outlined in a single blade or tooth, pointing in the same direction, whereby, when
the implement is subjected to a simultaneous edgewise and surface wear, the
surface of each cutter may be thinned by such wear, while its working edge is
being worn away.
8. An implement comprising substitute cutters projecting one into another, the
inner portion of the initial cutter being joined to the rudimentary edge of the
next succeeding cutter.
9. An implement comprising substitute cutters pointing in the same direction,

page_text: the inner portion of the initial cutter being joined integrally to the rudimentary
edge of the next succeeding cutter.
10. An implement comprising diagonally arranged substitute cutters pointing in
the same direction, the inner portion of the initial cutter being joined to the
rudimentary edge of the next succeeding cutter.
11. An implement comprising beveled substitute cutters, the inner portion of the
initial cutter being joined to the rudimentary edge of the next succeeding cutter.
12. An implement comprising substitute cutters each of graduated width, the
initial cutter being joined to the rudimentary edge of the next succeeding cutter.
13. An implement comprising substitute cutters outlined by grooves of varying
depth, each cutter being joined to the rudimentary edge of the next succeeding
cutter.
14. An implement comprising an initial cutter, a substitute cutter, an intervening
weakening element; and a strengthening tie connecting the two cutters.
15. An implement increasing in thickness from its outer edge inward, and
comprising a series of cutters, the inner portion of the initial cutter being joined
to the rudimentary edge of the next succeeding cutter.
16. An implement having a thin wearing body provided with a series of ribs or
elevations forming substitute working members, and bracing the body against
transverse strain, whereby, when the thickness of the implement is reduced by
wear, it shall give way between the outermost and next succeeding rib and expose
the latter as a substitute cutter or working member.
17. An implement comprising an initial and a substitute cutter outlined therein,
and an intervening, weakening element, the initial cutter being joined integrally to
the rudimentary edge of the next succeeding cutter.
18. The art of renewing the working edge of an implement, which consists in
thinning an integral metal plate or body on a line within its initial cutting edge,
thereby outlining a substitute cutter, and hardening or tempering the thinned
portion, and then wearing away the outermost cutter to expose the hardened edge
of the substitute cutter.
Deted this oth dow of IL-100%
CHARLES LA DOW.