Year: 1891

page_text: Date of Application, 7th Sept., 1891
Complete Specification Left, 29th Apr., 1892-Accepted, 25th June, 1892

page_text: space between the circle M and the extreme corner N of the square within the
dotted circle O at the points, a. a¹ all a¹¹. Then a line drawn from the corner N
of the square through the points a. a' all all will determine the exact form to be
given to the cone guide in order to produce a 3 inch square. hole. In a similar
manner if it be required to drill a polygonal hole then a circle must be described 5
within and without the figure and the distance P set off as above described.
The cone will have a number of steps d corresponding to the different sizes and
forms to be bored or turned and it may be made in one piece or in several sections
as may be found most expedient.
Dated this Seventh day of September 1891.
COMPLETE SPECIFICATION.
An Improved Apparatus or Tool Holder for Turning, Boring, and
Shaping Machines.
I WILLIAM JOHN SMITH of 28 and 29 St. Swithins Lane, in the City and
County of London, Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
This invention relates to an improved apparatus or tool holder applicable to
existing turning, boring and shaping machines, and my invention relates primarily
to boring by means of a tool which has two motions, one a motion on its axis as
usual in boring tools, and the other a motion with a carrier, the compounding of
these two motions giving the size and shape of the hole bored, when the path of the
tool is such as to bore a hole; and consists primarily in the combination of a tool
stock adapted to be rotated in any suitable way, a carrier compelled to rotate with
the tool stock, but adapted to move crosswise of the tool stock while the stock is
rotated, and a guide prevented from rotating and adapted to control the movement
of the carrier across the tool stock; the tool being fast to the carrier is thus
compelled to rotate but about the axis of the rotating tool stock, instead of upon
that axis; the rotating motion of the tool stock, and the crosswise motions of the
carrier giving the tool a compound motion, with the result that circular or non-
circular holes can be bored, and pins be turned to fit such holes.
Moreover by adjusting the tool relatively to the axis of the tool stock the size of
the hole bored or pin turned will be varied; and by changing the relation of the
cutting edge of the tool to the guide the shape of the hole bored, or pin turned will
be varied.
One form of my apparatus is illustrated upon the drawing left with my Provisional
Specification, in which :-
Figure 1 represents a sectional elevation of the tool holder attached to an ordinary
drill spindle,
Figure 2 a transverse section through the same on line 1-2,
Figure 3 a plan of the above on line 3-4,
Figure 4 a plan of the cone guide, as seen from below,
Figure 5 a side elevation of the same, and
Figure 6 a series of diagrams illustrating the method of arriving at the correct
amount of curvature to be given to the cone for a corresponding size of hole.
A. being the drill spindle. B. is the shank of tool holder. Č. the drill. D. the
cone guide. E. lever or arm secured on to cone guide. F. guide rod for same
attached to machine. G. roller pressing against cone. H. slide rest or tool holder.
1. stud for carrying roller. K. spring for keeping roller G pressing against.cone D:
La screw for adjusting position of drill.
Upon the drill spindle A being caused to revolve, the sliding tool holder H is

page_text: carried round with it, and this in its turn causes the roller G to revolve around the
cone guide D, whereby a reciprocating or oscillating motion corresponding to the
contour of the cone is imparted to the tool; the spring K. serving to keep the roller
in close contact with the cone at all times, and the cone kept from revolving by the
arm E engaging with and sliding upon the fixed stud F.
I construct my cone guide as follows :—
Having first determined the size and number of the various diameters or forms to
be bored or turned, the extreme or greatest diameter of the cone guide is then made
to correspond with the largest of the diameters to be so treated. In order to arrive
at the particular form or curvature of the cone, it is necessary that an exact diagram
of the hole or form required be drawn and that a circle M be described within the
same, as shewn in Figure 6.
The distance P from this circle M to the extreme corner N of the square will
determine the exact amount of curvature short of a true circle to be given to the
four sides of the cone guide. For example, if it be required to drill'à 3 inch
square hole, a 3 inch square must be drawn, and a circle M as shown in dotted lines
in Figure 6. Then a second circle O (also shown in dotted line) is drawn outside
the square and joining its four corners N. Next set off the distance P equal to the
space between the circle M and the extreme corner N of the square within the
dotted circle O at the points, a. a¹ a" al. Then a line drawn from the corner N
of the square through the points a, a, a", 2¹ will determine the exact form to be
given to the cone guide in order to produce a 3 inch square hole.
In the same way to find the exact form to be given to the cone to produce an
inch and a half square hole, draw an inch and a half square and in this describe the
cirale m; then from points a, a, a, all in the original figure set off the
distances y, y', y", y equal to the distance from the circumference of this smaller
circle m to the corner n of the inch and a half square. Then a line drawn from the
corners N through the points y, y', y", " will determine the exact form to be
given to this step of the cone in order to produce an inch and a half square hole.
In a similar manner if it be required to drill a polygonal hole, then a circle
must be described within and without the figure and the distance P set off' as
above described.
The cone will have a number of steps d corresponding to the different sizes and
forms to be bored or turned and it may be made in one piece or in several sections
as may be found most expedient.
A-simpler form of my machine is shown upon the drawings accompanying this'
Complete Specification in which :—
Figure 1 is an under plan of one form of the guide for the tool carriage;
Figures 2 and 3 are sections,
Figure 4 is a plan of the tool holder,
Figure 6 is a plan of the carrier, and
Figures 6 to 10 inclusive, illustrate various applications of my invention.
In this form of machine the outer end of the stock A is of usual construction
adapting it for the usual drilling of boring machines; but to the other end is
secured a block B. In the drawings the block B screws upon the stock A.
This block B supports the carrier D, which is so mounted upon block B that as
block B rotates with stock A. the carrier D can slide across the axis of rotation
of stock A. The ways d d' fast to carrier D fit in grooves in block B, and the
way d' is preferably adjustable on carrier D to allow for wear.
A stud d' fast to carrier D engages with guide F, which is, preferably, carried
by stock A, but does not rotate with it. Guide F is shown as a cup with the
outer end of stud d' travelling in it, the spring shown in dotted lines in Figure 5,
serving to ensure contact between them, and the stud d' is provided with the usual
anti-friction roll.
The operation of this, the simplest form of my machine, is as follows:-The
tool G being secured in any convenient manner to carrier D, (the means shown
need not be here considered, as they constitute another feature of my invention and

page_text: are fully described below) must move with carrier D, and as carrier D must
rotate with stock A and block B, a rotary motion of stock A causes tool G
to rotate also.
If now the grooves of guide F were concentric with the axis of stock A,
carrier D would simply rotate with stock A and block B, and be fed towards the
work as stock A and block B were so fed ; and if the axis of tool G were in line
with the axis of stock A, it would be in substance the same as if tool G were
secured directly to, and in line with, stock A, and the tool would then be a simple
boring tool. But if the axis of tool G be slightly out of line with stock A, the
tool Ġ will while it revolves move about the axis of stock A and bore a larger hole
than it could bore if in line with stock A; or if tool G be largely out of line
with stock A it will move in a longer path about the axis of stock A, and may thus
be made to cut a groove, instead of merely boring a hole.
From this it will be clear that if the guide be four sided as shown in the
drawings the motion of the carrier D will cause the tool G as it revolves, to cut a
four sided hole, as illustrated in Figure 8, and as will now be more fully explained
by reference to that figure. When the cutting edge to tool G gets to the position
shown in Figure 8, the axis of tool G is gradually moved as the tool rotates
towards the axis of stock A, by carrier D and guide F, thus causing the cutting
edge to follow one half of one side of the square; but then the axis of tool G is
gradually moved as the tool rotates away from the axis of stock A, by carrier D
and guide F, thus causing the cutting edge to follow the other half of one side of
the square, until the outer end of the cutting edge occupies the second corner of
the square. In this way, with a properly shaped guide, the axis of the tool is
gradually moved towards and from the axis of the stock, to bore the desired shape
of hole.
In Figure 9 the tool is shown as boring a four sided bore with four curved sides
thus illustrating the effect of merely changing the relation of the cutting edge of
the tool and the guide F; for in Figure 9 the axis of the tool is as near the axis of
the stock as it can be during a rotation when the outer end of the cutting edge is
at a corner of the bore (instead of being as far away as it can be during a rotation
as in Figure 8); the axis of the tool is then moved gradually away from the axis
of the stock as the tool rotates thus causing the cutting edge to follow one half of
one of the curved sides of Figure 9, and thence the axis of the tool is gradually
moved towards the axis of the stock, the cutting edge following the other half of
that curved side of Figure 9, until the outer end of the cutting edge is at the second
corner of Figure 9.
It will now be clear that guide F need not be four sided, but may be of a large
variety of shapes; and also that any one guide F will itself produce a variety of
shapes of bore, depending upon the relation of the cutting edge of the tool with
the guide.
It will also be clear that the adjustment of the axis of the tool with relation to
the axis of the stock is important, and for this reason I use a tool holder g,
connected to the carrier D, so that it may be accurately adjusted upon the carrier ;
and this is the second feature of my invention above referred to.
I prefer to use ways 9' 9³, (9' being adjustable as explained in relation to way d¹)
on carrier D which engage grooves in tool holder g; so that a screw g³, mounted
in carrier D, and engaging with holder g as a nut, can be used to adjust holder g
with relation to carrier D, thereby adjusting axis of tool G with relation to axis of
stock A.
It will be obvious that many changes of construction may be made not only as to
the devices for adjusting tool holder g on carrier D, but also as to other devices;
but it will nevertheless be clear that the two features of my invention above
described will be found in any apparatus which contains first a rotating tool
stock a carrier moving crosswise thereon and a guide giving this motion to the
carrier as the tool stock and carrier rotates; and secondly these parts and a tool
holder adjustable to the carrier.

page_text: I prefer to form the guide F with a number of grooves gradually of less perimiter,
as shown, and to make the stud d' adjustable to enter either of these grooves.
My machine is also well adapted to trimming off bolts and bolt heads as
illustrated in Figure 10; where h represents a round bar and where the tool
rotates about this bar, its axis being at its extreme distance from the axis of the
stock when the inner end of the cutting edge is at its extreme distance from
the axis of stock A; the axis of the tool being gradually moved nearer the axis of
the stock while cutting one half of one side, and then gradually moved further
away from the axis of the stock while cutting the other half of that side until
the inner end of the cutting edge is near the next corner, as will be clear without
further description.
It is not essential that the guide be cup shaped, for it may be the converse, as if
the hub of the guide shown were itself the guide; but in this case the springs
which keep the stud d' and guide in contact must do more work than in the
form shown.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The boring machine described made up of a stock, a carrier on ways crosswise
of the stock, and a guide to control the motions of the carrier; all organized for
operation substantially as described.
2. In combination, a tool stock, a carrier, a guide, a tool holder, and means for
adjusting the tool holder, and means for adjusting the tool holder in the carrier,
substantially as described.
3. The improved apparatus for turning boring and shaping machines hereinbefore
described with reference to the drawings.
Dated this Twenty-ninth day of Anril 1892