An Expanding Drill or Boring Bar for Boring Metals, applicable to Lathes, Boring, and Drilling Machines.
Year: 1891

page_text: Date of Application, 10th Oct., 1891
Complete Specification Left, 5th May, 1892-Accepted, 23rd July, 1892
PROVISIONAL SPECIFICATION.
An Expanding Drill or Boring Bar for Boring Metals, applicable
to Lathes, Boring, and Drilling Machines.
I, ALBERT HENRY HOYLE, of No. 3 Sunny Bank Street, Haslingden, in the
County of Lancaster, by calling a Teacher of Music, do hereby declare the nature
of this invention to be as follows:-
The drill, of which 1 send drawings, consists of a bar of iron or steel, rectangular
in section, having at one end, a loose cap-with provision for fastening-both of
which are provided with grooves or slots to receive two cutters, which slide one over
the other, and actuated by means of a small pinion wheel and two small racks.
Fig. 1 shows the bar, at one end of which, are three slots, parallel to each other,
and at right angles to length of bar. Slot a being for bottom cutter c, Fig. 3, and
as will be seen does not traverse entirely through the bar, but a thin portion of
metal is left standing equal in height to thickness of cutter.
The cutter slot in cap B, Fig. 2, is formed in the same manner, the portion of
metal left standing being at the opposite side.
The slots E and F, Fig. 1, are in section V-shaped, and are to receive the two
racks, which are in section, rectangular pieces of steel, their under surface being
prepared to slide in above slots, and having teeth formed on one of their upper
facets, so as to engage with the teeth of the small pinion wheel i, Fig. 3, situated
between them, the axis of the pinion, being prolonged in both directions, to go both
through the bar and cap-when the latter is in position-both ends being screwed
to receive a nut; see sectional elevation Fig. 4.
Un reference to Fig. 3 which shows racks G and H, wheel i, and bottom cutter, c,
in position, with cap and upper cutter removed, it will be seen that motion is
given to bottom cutter c through the wheel and rack G by means of a small
projection on the latter, engaging with a corresponding notch in the former, and
by means of a U-shaped piece of steel, attached to upper surface of rack H,
having the necessary projection to fit notch in upper cutter D, motion is given to
the latter in an opposite direction.
When the cutters, cap, etc. are in position, Fig. 4, the cutters can be moved
inwards or outwards by turning the nut ; secured to axis of wheel i and finally
held in position by means of bolt k.
Dated this 9th day of October 1891
ALBERT HENRY HOYLE.
COMPLETE SPECIFICATION.
An Expanding Drill or Boring Bar for Boring Metals, applicable
to Lathes, Boring, and Drilling Machines.
I, ALBERT HENRY HOYLE, of 3 Sunny Bank Street, Haslingden, in the
County of Lancashire, Teacher of Music, 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 has reference to a construction of expanding drill or boring bar
with laterally adjustable cutters and with adjusting mechanism whereby the
positions of the cutters relatively to the boring head can be adjusted simultaneously
as I will now proceed to more particularly explain with reference to the accom-
panying drawings wherein
.
Fig. 1 is an elevation of a boring bar constructed according to this invention;

page_text: with the means for securing the cutters and adjusting mechanism in place
removed; and
Fig. 2 is a sectional elevation thereof on the line x y Fig. 1.
1 and 2 are the cutters arranged to slide in transverse recesses 1 and 2ª respec-
tively in the two parts 3, 3° of the boring head, of which the latter part viz. 3*, is
made removable from the other. 4 and 5 are two slides arranged to work trans-
versely in an opening formed between the two parts 3, 3ª of the boring head.
Each of these slides is formed with a fillet 6 adapted to slide in a groove 7 in
the part 3 of the boring head and keep the corresponding slide in position.
Each slide is also formed with a rack 8 that gears with a pinion' 9, and with a
projection 10 that enters a recess 11 in the corresponding cutter. The two racks
are arranged at opposite sides of the pinion, and the one farthest from the cutters,
is provided with an extension 10 which carries the projection 10 that engages
with the cutter 2. The pinion 9 is fixed upon and held in place by a pin 12 one
end of which is flattened at opposite sides as shown at 12" to receive a correspond-
ingly formed key by means of which the pin and pinion can be rotated. As will
be seen the arrangement is such that if the pinion be turned in one direction it
will cause the racks and attached cutters to slide transversely in opposite directions
and cause the cutters to move simultaneously and equally either in an outward or
in an inward direction according to the direction in which the pinion is rotated.
The cutters and connected slides and racks are retained in the desired position by
the removable part 3ª of the boring head, one end 3" of which is tapered as shown
in cross section and arranged to enter a correspondingly formed recess 3° in the
other part 3, whilst the other end is firmly secured against the cutters by a bolt 13
with nut 14.
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. An expanding drill or boring bar constructed with laterally adjustable
cutters arranged to slide one over the other and each connected with a detachable
sliding rack in gear with a pinion, and with a clamp, the arrangement being such
that by turning the pinion the positions of the cutters relatively to each other and
to the boring head in a lateral direction can be adjusted simultaneously, and the
cutters can afterwards be clamped in their adjusted positions substantially as
herein before described.
2. "My improved expanding drill or buring bar, substantially as described' and
shown.
A. H. HOYLE,
By L. W., per F. B.