Improvements in Diamond Core Drills.
Year: 1897

page_text: Reprinted as amended in accordance with the decision of the Chief Examiner,
dated the 19th day of November, 1900.
Date of Application, 16th July, 1897-Accepted, 30th Oct., 1897
Improvements in Diamond Core Drills.
I, HENRY LOW WEBSTER, of Palace Hotel, Klerksdorp, in the South African
Republic, Engineer, 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
any and by the following statement:-
This invention relates to that class of boring or drilling tool or machine commonly.
called "diamond drills" or "diamond core drills," or those in which the boring portion
or face of the tool is composed of a number or series of diamonds or carbons, now
usually hammered or otherwise similarly worked by hand into a soft metallic or
other suitable "setting," and which are employed for the purpose of boring to
"prove" or demonstrate the existence of say a gold bearing or other ore in a par-
ticular area, or for the formation of-holes in rock, stone or the like for blasting or
similar operations in mines, quarries et caetera, and for other analogous uses.
The invention is designed, firstly, with the object of providing a simple, cheap and
much more efficient method or mode of "setting" or fixing the diamonds or carbons
to or on the cutting surface or edge of the boring crown, or face of the tool, or on or to
an intermediate part to be subsequently attached thereto, than has hitherto been
attained by the various methods einployed ;. and, secondly, of providing an improved
light, simple--and compact-mechanism or means of driving the-drill-or-of trans-
mitting the rotary-or-other-motion of n-motor mounted-or-supported thereon-to-the
operative parts of the diamond-core-or-drill.
It consists, essentially and firstly, in the method or mode of fixing or securing
the carbons on or to the cutting or working face or surface of the tool, or on or to an
intermediate part to be subsequently and suitably attached thereto, by the electro-
deposition of a suitable metal, which deposition is preferably carried or continued
until the carbons or carbon fragments are completely enveloped or embedded in and
by the metal so deposited or until the whole forms a homogeneous and solid mass on
the cutting face of the tool..
The invention as applied to the construction of a diamond core drill will be
more particularly described by aid of the accompanying sheet of drawings, in
which,
Fig. 1, is an elevation of a boring crown as employed in this class of machine.
Fig. 2, plan of the cutting or boring face of same.
Fig. 3, a sectional elevation of the boring crown and drill rod or core barrel to which
it is affixed.
Fig. 4, a sectional elevation of the crown shewn in Figs. 1, 2 and 3, but drawn to an
enlarged scale.

page_text: Fig. 5, a sectional elevation of a crown shewing a slightly modified form of con-
struction.
Fig. 6,-a-longitudinal part sectional elevation of a portion of a-diamond-core-drill
shewing-my-improved means-of-driving,-and
Fig. 7, a plan of a diamond core drill mounted on a column and shewing the
improved driving arrangement.
Referring to Figs. 1, 2, 3 and 4, A is the boring crown, B the drill rod or core
barrel, and C the diamonds, carbons or carbon fragments (boart) affixed to the cutting
or boring face of the crown by the electro-deposited metal D.
The method or process hereinafter particularly described may be-is employed in effect-
ing the fixing or attachment of the carbons to the cutting face of the crown, according to
this invention, but-it-is-to-be-distinctly understood that any other-process-or-method
may be adopted-in-substitution therefor, as may be desired or found more convenient
-in-practice.
The crown may be screwed as at a and the drill rod B be tapped to receive it, or
any other suitable means of attaching same thereto may be employed.
The cutting or boring face 6 of the crown is, in the construction adopted in Figs. 1
to 4, somewhat rounded. On the inner and outer rims or edges 61 62 small recesses
or steps are preferably formed, in order to present a bearing surface at right angles
to the path of travel of the crown for the carbons disposed around the edges.
In
For the purpose of retaining the carbons or carbon fragments in position
whilst the electro-deposition is being carried out, an annular mould of U
shape in
cross section, or one having the same, or approximately the same,
internal shape as the cutting face of the crown externally, may be employed.
A film or thin coating of wax, guttapercha, or other suitable non-conducting
plastic and adhesive substance or material is preferably given to the
mould in order to retain the carbons when they have been placed and slightly pressed
therein. The carbon fragments employed in any particular class of crown are pre-
ferably of a uniform size, varying only with the size of crown, and their surfaces are
preferably brushed or otherwise coated with a film of black lead of a suitable fine
quality, which materially assists the electro-deposition of the metal thereon. The
assorting of the carbon fragments may be effected by passing them over or through
sieves of varying grades or sizes of holes, or in any other convenient manner.
placing the carbons in position in the mould the sharpest or best shaped cutting edges
.will be directed downwards and towards the rims or edges of the crown when in
position, in order to give clearance when boring for the body of the crown, and the
distance between them should be approximately equal to their width or diameter, in
order to ensure solidity of the metal, deposited around them. The carbons are pre-
ferably arranged irregularly, that is to say, in such a way that, with the exception,
possibly, of the inner and outer rims or edges, they will not form rings on the face of
the crown, which arrangement would probably cause the abrasion of the deposited
metal. Guide and supporting pins or the like may be fixed within the mould to
direct and support the crown in its true relative position when placed on or over the
carbons arranged within the mould, and suitable means for attaching the mould
and crown together, preparatory to their being introduced into the electro-plating
bath, will be provided. The upper edges of the mould may be turned outwards, or
chamfered off, in order to permit of a free circulation of the solution between the
carbons and the surface of the crown to which they are to be affixed, when they are
connected and placed in the bath. Those portions of the crown on which no deposi-
tion of the metal is required will be insulated in any suitable manner.
After the crown has been secured in the desired position over the carbons in the
mould, the whole is immersed or placed in the electro-plating bath and the deposition
commenced slowly for a time, and continued until the metal deposited on the surface
of the crown has obtained a hold of the carbons. The mould may then be removed
and the deposition continued on the crown and on and around the carbons, until they
(the carbons) are completely enveloped by or embedded in the metal so deposited.
The crown is then removed from the bath, and any irregular or superfluous metal
removed by turning or otherwise until the points of the carbons are exposed.

page_text: The metal employed for the purpose of the deposit may be copper, silver, nickel,
iron or any other suitable metal according to the nature or hardness of the rock or
substance to be operated upon by the drill,.or the work to be performed.
By this method a solid and homogeneous and thoroughly efficient setting for the
carbons is obtained, and, particularly in the case of smaller sized crowns, it permits
the employment of a much cheaper carbon than is now ordinarily used, the article
known as "carbon dust" being able to be employed.
The carbons may be removed from their setting when worn for re-use by placing
the same in the bath and reversing the current.
It will be perfectly evident that instead of attaching the carbons direct to the work-
ing face of the crown, an independent or intermediate vehicle or piece may be
employed, to in which the carbons may be affixed fixed, and which would subsequently
be attached to the crown by soldering, brazing, or in any other suitable manner.
In Fig. 5 a modification is shewn in which the cutting face of the crown is square
or flat.
In this construction the recesses around the external and internal
With the exception
rims or edges of the crown would preferably be dispensed with.
of the variation in the shape of the mould, which in this case would be of square cross
section, slightly exceeding the diameter of the crown, the method of carrying out the
invention will be practically the same as that described with reference to Figs. 1
to 4.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I would have it known that I
do not claim broadly the setting of stones by electro-deposition of a suitable metal, as I
am aware that a process of that kind, adapted for setting large stones and involving
the preparation of a model of the finished article, as also a matrix corresponding
therewith has been proposed. My mode of procedure, dispensing with these adjuncts,
is specially designed for setting small stones, carbons and splinters, and I claim :-
declare that what I claim is:-
11
The method or mode of setting or fixing the diamonds or carbons to or on the
boring face or edge of a boring crown, or like boring tool, in the particular manner
herein described and consisting in the electro-deposition of a suitable metal on the
surface of the tool, which electro-deposition is continued until the carbons are held or
secured in position on the face of the tool. by the metal so deposited, substantially-as
described: