Improvements in Machines for Drilling, Boring, Well-sinking, and Tunnelling.
Year: 1886

page_text: Date of Application, 20th May, 1886.
Complete Left, 18th Feb., 1887.
Complete Accepted, 17th May, 1887.
Improvements in Machines for Drilling, Boring, Well-sinking, and
Tunnelling.
1, CUTHBERT BURNETT of Burn Terrace Hartlepool in the County of Durham
Engineer do hereby declare the nature of this invention to be as follows:-
These improvements refer to drilling, boring, well sinking and tunnelling machines
whether worked by hand or power and for working in metal minerals and other
materials. In such machines I provide the drilling or boring bar or head with a
series of conical friction rollers to take the thrust against the material operated on,
these rollers being of such conicity or size at their inner and outer end as to
correspond with the distance from centre of drill boring bar or boring head. In
ordinary drilling machines the aforesaid rollers would be arranged between the feed
nut and head or box. By the employment of such rollers the friction is greatly
reduced and thus also the driving power and the weight of the machine. Instead of
the conical rollers I may use hard steel or chilled cast iron balls working against hard
plane surfaces, but I prefer the conical rollers. In my provisional Specification of
25th January 1886 No. 1112 I have described similar thrust rollers with reference to
an apparatus for drilling holes specially applicable for use in mines quarries and the
like.
"
In order to be able to determine or regulate the rate of feed I arrange the feed nut
on the screwed drill bar so that it may be fixed or may have any desired amount of
slip." For this purpose I may apply one or more friction blocks against the nut or
a cone sleeve which is fixed on the feed driving part and can be brought to hear more
or less against a cone mandril part on the nut. The screwed drill bar may be formed
with two key ways or longitudinal recesses for sliding through a correspondingly
formed driving part. In my Provisional Specification of 12th February 1856 I have
described a similar adjustable slip feed in connection with an apparatus for drilling
holes in coal.
I
Instead of or rather in addition to the ordinary drill I may employ one or more
cutters inserted through and keyed to the foremost or point part of the drill. may
also form the point detachable, screwed into the end of the drill so that it can be

page_text: removed and exchanged for a new or differently formed point when needed because of
wear or damage or to suit the requirements of the material operated on.
In order to obtain a slow forward feed and a quick return and of special advantage
for hand worked machines I provide first and second motion in connection therewith
and form on the driving spindle a square or squares for a handle or handles and
connect this driving spindle by spur or other tooth wheel gear with another spindlo
which is worked for the quick return of the drill or boring bar or head. This is a
special advantage in a rock boring drill and also in a metal drilling machine. The
driving spindle may generally work the drill bar or head by mitre wheel gear, a box
carrying the feed nut and screw feed bar being mounted on a spindle fitted with mitre
wheel so that the drill may be swivelled or placed at any required angle without
interfering with or altering the position of the handle or handles or it may be ratchet
lever or levers. The frame of the machine proper may slide on round steel or other
bars formed with a flat on the front for the set screws to bear against, so that the
frame can be fixed thereby, the two bars being united by cross pieces at top and
bottom to form a frame and with screw or screws provided at each place for fixing this
frame against the roof and floor of the passage or tunnel. After having been thus
fixed, the machine proper can be slided up and down on the round bars and be fixed
by the set screws in any required working height.
JENSEN & SON,
77, Chancery Lane, W.C.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Machines for Drilling, Boring, Well Sinking, and
Tunnelling.
I CUTHBERT BURNETT of Burn Terrace Hartlepool in the County of Durham
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:-
These improvements refer to drilling, boring, well sinking and tunnelling machines
whether worked by hand or power and for working in metal minerals and other
materials.
Figure 1 of the accompanying drawings is a side view of a machine constructed
according to this invention, Figure 2 an end view and Figures 3, 4 and 5 detail
views. This construction is specially suitable for boring in coal and other mineral
and advantageously applicable in connection with my Mining Wedge patented
27th April 1885, No. 5198. In such machines I provide the drilling or boring bar a
or heade with a series of conical friction rollers d to take the thrust against the
material operated on, these rollers d being of such conicity or size at their inner and

page_text: outer end as to correspond with the distance from centre of drill boring bar or boring
head. The rollers & are arranged between the cap c of the feed nut and the head or
box e which has a lip or rim e all round for retaining the rollers & in place as shown.
Figure 5 is a plan view of the cone rollers, in this case 16 in number. It must be
noted that these conical rollers are comparatively long and are so many in number as
to leave no appreciable space between them and are thus free to touch each other, and
I find this arrangement very suitable for the severe end pressure to which this
machine is exposed when working in coal and other harder mineral, and as being
decidedly preferable to a smaller number of conical rollers in the same space, which
rollers then as a consequence necessarily would have to be kept apart or in place by
some means and are not nearly so frictionless as the arrangement shown here which
is also decidedly preferable to the use of balls, as I have found by practical
experience (and that even if the number of balls is such that they touch or all but
touch each other) because the amount of frictional contact is not sufficient and only
causes indentations in the parts cand e and defeats the object in view which is to
produce a drill for coal and other minerals and substances without appreciable end
thrust or friction so that the tool can be worked to advantage and without fatigue to
the workman, or heavy wear and tear to the machine. By the employment of such
rollers d the friction is greatly reduced and thus also the driving power and the
weight of the machine. Instead of the conical rollers I may however for boring in
softer material than coal use hard steel or chilled cast iron balls working against hard
plane surfaces, but I also in such case prefer the conical rollers and which I specially
claim as novel for the purpose.
In order to be able to determine or regulate the rate of feed I arrange the feed
nut on the screwed drill bar a so that it may be fixed or may have any desired
amount of slip. For this purpose I may apply one or more friction blocks w w¹ see
Figures 3 and 4 which are let into slots in the head or box e. These blocks are
pressed more or less against the feed nut b. The blocks w w¹ are surrounded by a
ring or band y which is provided with a spring y' and a thumb screw y² which serves
to adjust the rate of feed, or the band may be made sufficiently flexible to dispense
with the spring y. The action of the feeding arrangement is as follows: when it is
desired to give an increased feed to the drill the thumb screw y² is screwed up tighter
thereby compressing the spring y' and tightening the pressure of the blocks on the
feed nut and stopping the revolution of the same to a certain extent. If the
revolution of the nut were stopped altogether it follows that the boring bar a would
simply go forward at the rate of the full pitch of the screw (which pitch may be
varied as required). The advantage of this quick motion will afterwards he pointed
out. In drilling a hole, the drill would soon stick in the material to be drilled and if
enough force were applied would break. But as stated there is a constant and light
pressure on the feed nut 6 by reason of the spring y' which squeezes the two friction
blocks together and the said feed nut being thereby retarded and revolving at a
somewhat slower rate than the boring bar a it follows that the boring bar a moves
slowly forward as well as revolves and thereby drills a hole. The screwed drill bar a
may, as hereinafter to be referred to, he formed with two key ways or longitudinal
recesses for sliding through a correspondingly formed driving part.
Instead of or rather in addition to the ordinary drill I may employ one or more
cutters inserted through and keyed to the foremost or point part of the drill. I may
also form the point detachable, screwed into the end of the drill so that it can be
removed and exchanged for a new or differently formed point when needed because
of wear or damage or to suit the requirements of the material operated on, or I may
use a cylindrical cutting head either serrated at the end or with cutters attached
thereto for the purpose of cutting an annular groove, and thus liberate the material
in cores.
In order to obtain a slow forward feed and a quick return which is of special
advantage for hand worked machines I provide first and second motion in connection
therewith and form on the driving spindle y a square or squares for a handle or
handles and connect this driving spindle by spur wheels h, and / or other tooth

page_text: The trunnion
wheel gear with another spindle k which is worked for the quick return of the drill
or boring bar or head. This is a special advantage in a rock boring drill and also in
a metal drilling machine. In using the quick motion the nut c may be firmly secured
by the thumb screw y³. The driving spindle k may generally work the drill bar or
head by mitre wheel gear n and o. The bevel wheel n is loose on its spindle and
fixed to or in one with the spur pinion 1, and the bevel wheel o is connected to tho
screw a by means of two keys o' o² which take into recesses in the bevel wheel o and
into two opposite grooves extending the whole length of the screw a.
m which is fixed to (or it may be formed in one with) the head or box e carrying the
feed nut and screw feed bar is mounted loosely on a spindle fitted with the mitro
wheel n so that the drill may be swivelled or placed at any required angle without
interfering with or altering the position of the handle or handles (or it may be ratchet
lever or levers, and which latter may also if desired be applied to the spindle of
mitre wheel ndirect, the spur wheels being then omitted, but I do not recommend such
arrangement) and fixing it at any desired angle by means of the nut m', the working
height nevertheless remaining the same at all angles. The frame r of the machine
proper may slide on round steel or other bars pp³ formed with a flat p² p³ on the
front for the set screws 77' to bear against, so that the frame can be fixed thereby,
the two bars being united by cross pieces s slat top and bottom to form a frame and
with screw or screws provided at each place for fixing this frame against the roof and
floor of the passage or tunnel. The bars pp¹are in the case here shown formed with
points at the top, and a screw u screws into the bottom cross piece s¹ and is
provided with a swivelling foot a which on turning the screw u by means of a
turning or lever inserted in the holo u¹ enables the machine to be firmly fixed between
the floor and roof of mine or tunnel. After having been thus fixed, the machine
proper can be slided up and down on the round bars p p¹ and be fixed by the sot
screws in any required working height.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim is :-
First In a drilling or boring machine the application of a number of long loose
conical friction rollers c enclosed in and filling a space provided on or in connection
with the drill bar or feed screws in line therewith, so as to relieve the end thrust
substantially as set forth, also the special arrangement here illustrated.
Second: In a drilling or boring machine adjusting the rate of feed by means of a
scrow y² and a spring y enclosed in a band y, such screw acting on friction
blocks we w¹ let into slots in the head or box e so that the feed nut b may have more or
less frictional adhesion to or be quite free of the head or box e substantially as
described and shown.
Third: In a drilling machine or boring machine, revolving the feed screw a and
boring tool forward by bevel wheel gear o n; spur whools and h and handle or
handles on the spindle of the latter wheel or revolving the feed screw a quickly
back by bevel wheels on and spur wheels and handle placed on the spindle of
the latter wheel, the gearing being so mounted on the framing as to be placed in any
convenient working height and with the drill at any desired angle without altering
such working height substantially as described and shown.
Fourth: The general combination and construction of parts forming the improved
boring or drilling machine substantially as described and shown.
CUTHBERT BURNETT.
By Jensen & Son,
77, Chancery Lane, London, W.C.,
Patent Agents.