Improvements in Well-boring Apparatus.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Well-boring Apparatus.
I, CAMILLO LOUIS SCIPION ISLER, of Artesian Works, Bear Lane,
Southwark, Artesian-well 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 and by the following statement :-
My invention relates to improvements in well-boring apparatus and has for its
object to increase the strength of the screw-joints by which the lengths of the
drill rods are connected together and to enable drill bits or blades, of the same or
different shapes or sizes to be affixed to one holder so as to facilitate repair or
renewal of the tool or its exchange for another of a different shape or size as
may be required and reduce the cost of manufacture by avoiding the welding of
the bit or blade to the holder.
The invention will be described with reference to the accompanying drawings,
forming part of this Specification, wherein
Figure 1 is a longitudinal section through the two parts of the improved joint
shewn separated whilst
Figure 2 is an external view of the parts united.
Figures 3 and 4 are face and edge views of the bit or blade holder.
Figures 5 and 6 are corresponding views of the bit or blade shewn separately
and to a smaller scale.
Figures 7 and 8 are similar views of the holder with a bit or blade affixed, the
latter being provided with curved extensions at one side forming side cutting edges
and the holder being provided with a safety chain to ensure the bringing up of
the bit in case of breakage, of the holder in the hole.
Figures 9 and 10 are face and edge views of the bit separately, on a smaller
scale.
Referring to Figures 1 and 2, it will be seen that each part of the improved
screw-joint is both male and female, that is to say the one part has an externally-
threaded or male part a which screws into a corresponding internally-threaded
socket or female part 6 and that around the latter is an externally-threaded or
male part c which screws into a corresponding internally-screwed socket d around
the first mentioned part a. The inner screw-joint a, b, is preferably of the greater
length so as to be first engaged in screwing up, but the threads of both the inner
and outer screw-joints thus formed correspond in pitch, direction, and position with
regard to each other so that the threads of the outer and shorter one cd will
become engaged in the act of screwing up the inner one, the double joint thus
formed affording far greater strength than is obtainable with a single joint of the
same size.
In Figures 1 and the joint is shewn applied to tubular rods but it is equally
well adapted for solid rods, as shewn in section in Figure 3 and whether the rods
be of square or round section externally.
at its
Referring to the other figures, the tool holder terminates in a forked or slotted
end e in which the bit or blade fits, the latter having lugs or shoulders g
upper end which embrace the sides of the holder, as shewn in Figures 7 and 8,
the bit being secured in the holder by bolts passing through holes in both and
secured by nuts, the bolt heads and nuts being countersunk in the faces of the bit
holder.
To guard against loss of the bit in the hole by breakage of the holder, a
chain may be led through a hole in the bit and attached to the ends of a
crosshead i fixed upon the drill rod above the first joint as shewn.
The bit or blade may be of the form shewn in Figures 5 and 6, or in certain

page_text: cases it may have additional curved side cutting edges k, as shewn in Figures 7 to
10 for trimming the.sides of the hole.
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. The herein.described double male and female screw-joint for well-boring drill.
rods, as specified.
2. In a well-boring tool, the herein described holder and separable' bit or blade
fitting therein and secured by shoulders and bolts, as specified.
3. In a well-boring tool, the combination, with the herein described holder and
bit or bladet secured as described; of the safety chain applied as and for the
purpose-specified.
Dated this 15th day of December 1809
C. L. S. ISLER,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
C. L. S. ISLER,'
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.