Improvements in Tools for Boring Conical Holes in Metal, Wood, and other Materials.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Tools for Boring Conical Holes in Metal, Wood,
and other Materials.
We, LOUIS FREDERICK CHARLES RICH, Electrician, of Lansdown Crescent,
Cheltenham, and JOHN HENRY HULL, of 40, Park Row, Times Buildings, New York,
United States of America, Counsellor at Law, do hereby declare the nature of this
invention to be as follows:-
This invention relates to augers or boring tools (hereinafter called augers) by means
of which it is possible to widen the inner end of the cylindrical hole bored in wood
and other material by means of cutters that are forced gradually outward in a lateral
direction during the rotation of the auger by causing them to travel over inclined
surfaces forming the bottom of recesses cut in a guide-piece so that the widened
portion of the hole receives a conical shape.
Now this invention has reference to various improvements in augers of the kind
referred to as we shall now proceed to explain with the aid of the accompanying
drawings wherein Fig. 1 shows a piece of wood or other material in which are bored
cylindrical holes the inner ends of which it is desired to enlarge. Fig. 2 shows
partly in side elevation and partly in section, one construction of our improved auger
specially suitable for use in enlarging holes in metal. Fig. 3 is a cross section on the
line ww of Fig. 2. Figs. 2^, 45 and 6 are detail views hereinafter more particularly
referred to. Figs. 7 and 8 are elevations at right angles to each other showing a modified
construction of auger adapted for use with wood and like material, and Figs. 9 and 10
are cross sections thereof on the lines x x and y y respectively of Fig. 8. Figs. 11
and 12 are elevations at right angles to each other, the latter partly in section,
showing a further modified construction of auger suitable for use with wood and like
material. Figs. 13 to 17 are detail views thereof, hereinafter more particularly
referred to.
Fig. 1 shows a cylindrical hole 1 in a piece of wood or other material 2, and at 1*
is shown how the inner end of such a hole is to be enlarged by the cutters 3 (Fig. 2)
which are caused to travel over the inclined ways 4 forming the bottom of recesses 4*
cut in a guide piece 5.
Now according to this invention in order to retain the guide-piece 5 in the
widened hole 1 and permit the cutters 3 to be easily withdrawn after the boring out,
without damaging the side of the hole, and without its being necessary to provide
the guide-piece with any special clamping or fixing device which is objectionable,
there is employed according to this invention a spiral spring 6 (Fig. 2). This spring
is placed in a tube 7 to which the cutters 3 are jointed by pin 8, and the spring
bears with one end against a plug 7* screwed into the end of the tube 7 and with
the other end against the spindle 9 which carries the guide-piece 5. The spring 6,
which loosely surrounds a spindle 7b on the plug 7*, has a constant tendency to press
the tube 7 upwards on the spindle 9. This spindle 9, which may be made in one
with the guide-piece as shown in Figs. 2 and 3, or have separate guide pieces

page_text: attached to it, is held in the tube 7 by a screw 9*, which abuts against a shoulder 7*
in the tube when the spindle and tube are pressed fully apart.
To enable the cutters 3 to be quickly removed for sharpening, each of them is
provided at its upper end with an open slot 3* (see Figs. 4 and 5) by means of which
they can be simply hooked onto the pivot-pins 8 of the tube 7. Blade springs 10
press the cutters 3 against the inclined surfaces 4. These springs are provided with
two slots 10 and 105 (Fig. 6) through which pass the screws 10° and 10d. The
upper slot 10* is short and open so that upon loosening the screws 10° and 10d and
drawing down the spring, the slot 10" comes out of engagement with the screw 10°
and the blade-spring 10 can then be turned about the screw 10d so far that it no
longer presses on its cutter 3. This cutter can then be easily removed from the
pivot-pin 8.
To prevent the cutters 3 from being thrown outward by centrifugal force and
consequently boring a larger hole than desired, or injuring the widened hole, which
might take place when the tool is driven at a high velocity, the sides of the
recesses 4*, in which the cutters work, may be under-cut in dove-tail fashion, and
the corresponding cutters be guided in these undercuts.
To facilitate the escape of the shavings or cuttings produced by the cutters 3, the
exterior of the cylindrical guide-piece 5 may be provided, as shown, with a number
of spiral grooves 5* (see Figs. 2 and 3), or the guide-piece may be made of simple
conical form without such grooves 5ª, as indicated in dotted lines in Fig. 2.
The spindle 7b (Figs. and 2) is of such a length that it abuts against the
inner end 9* of the spindle 9 when the latter has ascended within the tube 7 to the
distance that is to be cut by the cutters 3 when within a hole 1 (Fig. 1).
It is also desirable that the normal position of the cutters 3 be capable of being
altered in order to compensate for the wearing away of their cutting edges by use
and sharpening. This adjustment is effected by means of the screw-plug 7 which
can be screwed more or less into the upper end of the tube 7, whereby the distance
between the inner end of the spindle 7b and the screw 9 can be altered and the
travel of the spindle 9 consequently regulated, and it is possible to push the cutters 3
forward when they are worn away. In order to enable the spring 6 to be more
easily changed, it is loosely mounted on the spindle 7b, but its upper end is located
in a groove 7 of the spindle 7b in order to prevent the spring from falling off the
latter and facilitating its removal.
Figs. 7 to 10 inclusive show a modification of the auger in which the guide-piece
5 is flat and has inclined grooves 4ª running on its opposite faces obliquely to its axis.
The cutters 3 are thus caused to move outwards as they descend and thereby widen
the hole to a corresponding degree. The cutters are held in the grooves 4* by the
undercut sides of the latter (Fig. 10). Instead of connecting the cutters 3 with the
tube 7 by ineans of pins 8 (see Fig. 2) their upper ends 11 are in this case made
hook-like and engage in slots 11* of the tube 7 in such a manner that the cutters
can move laterally. To enable the cutters to be withdrawn for sharpening or changing,
a part of the groove 4* is limited by a flange 5b that can be detached by withdrawing
& screw 5c
Figs. 11 and 12 show a modification in which a single cutter 3 is mounted in a
groove 4* formed in a plate 12, which is shown separately in elevation in Fig. 13 and,
as regards its upper part, in section on the line 14 of Fig. 13, in Fig. 14. This plate
12 is so mounted on the guide-piece 5 (shown separately in elevation, with its spindle
9, in Fig. 15) that it can be moved transversely thereon so as to vary the initial
distance of the cutter 3 from the axis of the tool to adapt the tool for widening
holes of different diameters, and can be turned on the guide-piece 5 in order to alter
the angle made by the groove 4* with the axis of the tool so as to vary the conicity
of the enlarged part 1 of a hole (Fig, 1). For these purposes the plate 12 is secured
to the guide-piece 5 by set screws 13 and 14 which pass through slots 15 and 16
respectively in the guide-piece 5 and fit in screw threaded holes in the plate 12 (see
Fig. 12 and Fig. 16, which is a section on the line 16 of Fig. 11) the heads of
the set screws 13 and 14 being received in suitable recesses made in the guide-piece 5

page_text: (see Fig. 12 and dotted lines in Fig. 15). The irregular shape of the slot 16 is
necessitated by the unequal adjustment allowed at the top and bottom of the guide-
piece 5 in the example shown the lateral adjustment allowed at the top is half that
allowed at the bottom. The cutter 3 is connected to the tube 7 by a cylindrical
projection 3*, which engages in a transverse groove 17 in the latter. The cutter 3
is retained in place in the groove 4", in the example shown, by a spring-nut 3b (see
Fig. 12 and Fig. 17 which is a plan of the auger inverted) that fits on a screw-
threaded projection (not shown) extending from the cutter 3 through a slot 4b made
through the plate 12, and bears against the rear face of the guide plate 12.
The tube 7 may advantageously in all cases be provided with a hole 7° (see
Figs. 11 and 12) to allow of the free egress of air when the spindle 9 ascends in
the tube 7.
COMPLETE SPECIFICATION.
Improvements in Tools for Boring Conical Holes in Metal, Wood
and other Materials.
We, LOUIS FREDERICK CHARLES RICH, of Lansdown Crescent, Cheltenham, in the
County of Gloucester, Electrician, and JOHN HENRY HULL, of 40, Park Row, Times
Buildings, New York, United States of America, Counsellor at Law, 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 relates to augers or boring tools (hereinafter called augers) by
means of which it is possible to widen the inner ends of cylindrical holes bored in
wood and other materials by means of cutters that are forced gradually ontward in a
lateral direction during the rotation of the auger by causing them to travel over
inclined surfaces forming the bottom of recesses cut in a guide-piece so that the
widened portion of the hole receives a conical shape.
Now this invention has reference to various improvements in augers of the kind
referred to as we shall now proceed to explain with the aid of the drawings accom-
panying our provisional specification wherein Fig. 1 shows a piece of wood or other
material in which are bored cylindrical holes the inner ends of which it is desired to
enlarge. Fig. 2 shows partly in side elevation and partly in section, one construction
of our improved auger specially suitable for use in enlarging holes in metal. Fig. 3
is a cross section on the line ww of Fig. 2. Figs. 2, 4, 5, and 6 are detail views
hereinafter more particularly referred to. Figs. 7 and 8 are elevations at right
angles to each other showing a modified construction of auger adapted for use with
wood and like material, and Figs. 9 and 10 are cross sections thereof on the lines xx
and y y respectively of Fig. 8. Figs. 11 and 12 are elevations at right angles to each
other, the latter partly in section showing a further modified construction of auger
suitable for use with wood and like material. Figs. 13 to 17 are detail views thereof,
hereinafter more particularly referred to.
Fig. 1 shows a cylindrical hole 1 in a piece or wood or other material 2, and at 1* is
shown how the inner end of such a hole is to be enlarged by the cutters 3 (Fig. 2)

page_text: which are caused to travel over the inclined ways 4 forming the bottom of recesses 4ª
cut in a guide piece 5.
Now according to this invention in order to retain the guide piece 5 in the
widened hole 1' and permit the cutters 3 to be easily withdrawn after the boring
out, without damaging the side of the hole, and without its being necessary to
provide the guide-piece with any special clamping or fixing device which is
objectionable, there is employed a spiral spring 6 (Fig. 2). This spring is placed
in a tube 7 to which the cutters 3 are jointed by pin 8, and the spring bears
with one end against a plug 7* screwed into the end of the tube 7 and with the
other end against the spindle 9 which carries the guide piece 5. The spring 6,
which loosely surrounds a spindle 7° on the plug 7, has a constant tendency to
press the tube 7 upwards on the spindle 9. This spindle 9, which may be made in
one with the guide piece as shown in Figs. 2 and 3, or have separate guide pieces
attached to it, is held in the tube 7 by a screw 9, which abuts against a shoulder 7* in
the tube when the spindle and tube are pressed fully apart.
To enable the cutters 3 to be quickly removed for sharpening, each of them
is provided at its upper end with an open slot 3* (see Figs. 4 and 5) by means
of which they can be simply hooked onto the pivot-pins 8 of the tube 7. Blade
springs 10 press the cutters 3 against the inclined surfaces 4. These springs are
provided with two slots 10" and 10° (Fig. 6) through which pass screws 10c
and 10d. The upper slot 10" is short and open so that upon loosening the screws 10°
and 10d and drawing down the spring, the slot 10 comes out of engagement
with the screw 10° and the blade spring 10 can then be turned about the screw 10d
so far that it no longer presses on its cutter 3. This cutter can then be easily
removed from the pivot-pin 8.
To prevent the cutters 3 from being thrown outward by centrifugal force and
consequently boring a larger hole than desired, or injuring the widened hole,
which might take place when the tool is driven at a high velocity, the sides of
the recesses, in which the cutters work, may be under-cut in dove-tail fashion,
and the corresponding cutters be guided in these undercuts.
To facilitate the escape of the shavings or cuttings produced by the cutters 3, the
exterior of the cylindrical guide-piece 5 may be provided, as shown, with a number
of spiral grooves 5" (see Figs. 2 and 3), or the guide piece may be made of simple
conical form without such grooves 5ª, as indicated in dotted lines in Fig. 2.
The spindle 7b (Figs. 2 and 2) is of such a length that it abuts against the
inner end 9* of the spindle 9. when the latter has ascended within the
tube 7 to the distance that is to be cut by the cutters 3 when within a hole 1
(Fig. 1).
It is also desirable that the travel of the cutters 3 he capable of being adjusted in
order to compensate for the wearing away of their cutting edges by use and sharpening.
This adjustment is effected by means of the screw plug 7" which can be screwed
more or less into the upper end of the tube 7, whereby the distance between
the inner end of the spindle 7° and the screw 9" can be altered and the travel
of the spindle 9 consequently regulated, and it is possible to push the cutters 3 a
greater distance along the inclined guides when they are worn away. In order to
enable the spring 6 to be more easily changed, it is loosely mounted on the spindle 7",
but its upper end is located in a groove 7° of the spindle 7b in order to prevent the
spring from falling off the latter, and facilitating its removal.
Figs. 7 to 10 inclusive show a modification of the auger in which the guide-piece 5
is flat and has inclined grooves 4ª running on its opposite faces obliquely to its axis.
The cutters 3 are thus caused to move outwards as they descend and thereby
widen the hole to a corresponding degree. The cutters are held in the grooves 4* by the
undercut sides of the latter (Fig. 10). Instead of connecting the cutters 3 with the
tube 7 by means of pins 8 (see Fig. 2) their upper ends 11 are in this case made
hook-like and engage in slots 11* of the tube 7 in such a manner that the cutters can
move laterally. To enable the cutters to be withdrawn for sharpening or changing,

page_text: a part of the groove 4* is formed by a flange 5³ that can be detached by withdrawing
a screw 5c.
Figs. 11 and 12 show a modification in which a single cutter 3 is mounted in a
groove 4* formed in a plate 12, which is shown separately in elevation in Fig. 13 and,
as regards its upper part, in section on the line 14 of Fig. 13, in Fig. 14.
This
plate 12 is so mounted on the guide piece 5 (shown separately in elevation, with its
spindle 9, in Fig. 15) that it can be moved transversely thereon so as to vary the
initial distance of the cutter 3 from the axis of the tool to adapt the tool for widening
holes to different diameters, and can be turned on the guide piece 5 in order to alter
the angle made by the groove 4ª with the axis of the tool so as to vary the conicity
of the enlarged part 1 of a hole (Fig. 1). For these purposes the plate 12 is secured
to the guide piece 5 by set screws 13 and 14 which pass through slots 15 and 16
respectively in the guide piece 5 and fit in screw threaded holes in the plate 12 (see
Fig. 12 and Fig. 16, which is a section on the line 16 of Fig. 11) the heads of the set
screws 13 and 14 being received in suitable recesses made in the guide-piece 5 (see
Fig. 12 and dotted lines in Fig. 15). The irregular shape of the slot 16 is necessitated
by the unequal adjustment allowed at the top and bottom of the guide piece 5; in the
example shown the lateral adjustment allowed at the top is half that allowed at the
bottom. The cutter 3 is connected to the tube 7 by a cylindrical projection 3ª, which
engages in a transverse groove 17 in the latter. The cutter 3 is retained in place in
the groove 4, in the example shown, by a spring nut 3b (see Fig. 12 and Fig. 17
which is a plan of the auger inverted) that fits on a screw threaded projection (not
shown) extending from the cutter 3 through a slot 4 made through the plate 12, and
bearing against the rear face of the guide plate 12.
The tube 7 may advantageously in all cases be provided with a hole 7° (see
Figs. 11 and 12) to allow of the free egress of air when the spindle 9 ascends in the
tube 7.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
1
1. An auger or boring tool of the kind herein referred to wherein a spring is
arranged between the spindle carrying the guide piece with inclined guide surface or
guide surfaces and the tubular holder mounted to slide endways on the spindle and
carrying a cutter or cutters arranged to work on the said guide piece, the said spring
having a tendency to move the said holder upwards on the said spindle and serving
after the widening of a hole, to hold the guide piece in the widened hole and permit
of the cutters being easily withdrawn without damaging the side of the hole, substan-
tially as herein described.
2. An auger or tool of the kind specified in the preceding claim in which the
tubular holder is provided with means such as a longitudinally adjustable screw
plug 7 with spindle 7b whereby the extent of longitudinal movement of the cutters
upon the guide piece, can be regulated, and the travel of the cutters upon the guide
piece can be adjusted to compensate for wear, substantially as described.
3. An auger or tool of the kind herein referred to in which the cutter or each cutter
is guided in an inclined guide-way formed on the face of a flat guide piece and is
connected with the holder in such a manner that it is free to move laterally thereon
when it descends the said inclined guide-way, substantially as described.
4. An auger or tool of the kind herein referred to wherein the guide way for the
cutter is formed in a guide plate that is adjustably connected to the guide piece in
such a manner that it can be moved transversely upon the said guide piece so as to
vary the initial distance of the cutter from the axis of the tool and adapt it for
widening holes of different diameters, and also can be partly turned on the said guide
piece in order to alter the angle of the guideway of the said guide plate to the axis
of the tool so as to vary the conicity of the widened part of a hole, substantially as
herein described.

page_text: 5. The improved augers or boring tools constructed, arranged and operating sub-
stantially as herein before described with reference respectively to and shown in Figs. 1
to 6 inclusive; in Figs. 7 to 10 inclusive; and in Figs. 11 to 17 inclusive of
the drawings.