IMPROVE- MENTS IN MACHINERY FOR TENONING, GROOVING, SAWING, AND OTHERWISE CUTTING Wood
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by Samuel Lumb and John Spink
at the Office of the Commissioners of Patents, with their Petition,
on the 12th February 1863.
We, SAMUEL LUMB, of Whitehall Works, Leeds, Engineer and Machine
Maker, and JOHN SPINK, of Oxford Road, Sheffield, Joiner, both in the
County of York, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN MACHINERY FOR TENONING, GROOVING, SAWING, AND OTHERWISE CUTTING
Wood," to be as follows:-
This Invention has for its object improvements in machinery for tenoning,
grooving, sawing, and otherwise cutting wood. In constructing a tenoning,
grooving, and sawing machine we employ two parallel axes so arranged that
the distance between them can be adjusted, each axis for this purpose being
mounted on a slide on the main frame, and the slides are capable of being
traversed by screws, each slide having two screws, one near each of its ends,
and these screws are turned simultaneously by means of bevilled gear from an
axis at right angles to them; these parallel axes carry the tenoning cutters.
The cutters for cutting the flat of the tenon are of ordinary construction; but
to cut the shoulder of the tenon, in place of employing straight cutters sharp
at the end, as is usual, we employ discs of steel sharpened all round; these
are each connected with the cutter head by a central screw, so that when' by

page_text: use one portion of the cutting edge of the disc bas become dull, another
portion can be brought up by turning the disc partly round, and this without
in any way interfering with the adjustment of the machine, whereas with the
ordinary cutters, when the one cutting edge becomes dull, it is necessary to
remove the cutter, sharpen it, and then carefully adjust it in its place in the
machine, so that it may cut neither too shallow or too deep. Means are
provided for setting the centre screw or axis of the disc cutter in or out from
the axis, as may be required.
In order that tenons may be cut in which the shoulder on one side of the
piece of wood is further from the end thereof than the shoulder on the other,
we make one of the cutter heads to slide longitudinally on its axis. In order
to obtain this adjustment we prefer to employ a screw passing through the
head, and entering a hole tapped in the end of the axis, and we clamp the
head in its proper position when it has been adjusted. The cutter axes have
heretofore usually been mounted between centre points at their ends, but this
arrangement is both dangerous and inconvenient, as the axes which revolve
very rapidly sometimes escape from the points. In other cases the axes have
been mounted in ordinary straight bearings, but these soon wear so as to
allow endway play, which causes them to produce untrue work.
According to our Invention, we mount the cutter axes in conical bearings,
there being two cones on each axis to run in the bearings, and one of these
cones is adjustable so that it can be set up to compensate for wear.
This
part of our Invention is also applicable in other wood-cutting machinery to
the axes which carry the cutting tools.
The table for presenting the wood to the tenoning cutters is capable of
being moved to and fro on guides fixed at right angles to the cutter axes; the
table has no vertical adjustment, this not being necessary, the cutter axes
being both capable of being raised and lowered, consequently we are able to
make the table steadier than it is in ordinary machines, in which only one
cutter axis is made adjustable, and in which, consequently, the table is obliged
to be made so that it can be raised and lowered. On the table we mount a
bar carrying two stops, which can be set to any required distance apart. The
further stop is used as a gauge for the wood in cutting the first tenon, the
outer end of the piece of wood then resting against it. The second stop
serves as a gauge in cutting the second tenon when the piece is turned end
for end, the shoulder of the tenon previously cut then resting against the
nearer stop.
The bar which carries the stops is made to slide on the table to and from

page_text: this
the cutters, and this motion can be given to it by means of a screw;
allows of an easy and accurate adjustment of the distance between the tenons
at each end of the piece.
In the tenoning machine, in connection with the further extremity of one
of the cutter axes, we mount a circular saw, and there is a fixed saw table
bolted to the frame. The saw is mounted in such a manner that it can be
set so as to incline to its axis, or become what is known as a drunken saw,
suitable for cutting grooves; this we do by fixing a cap on the end of the
cutter axis, and hingeing to it on one side a block, to which the saw is secured.
By causing the block to move about its joint the saw can be made to incline
to any extent desired. The adjustment is given by means of a screw passing
through a hole tapped in the cap on the cutter axes, and connected to the saw
block; the adjusting screw is placed on the opposite side of the axis to that
on which the joint is situated.