Improvements in Dovetailing Machines for Open Dovetails.
Year: 1887

page_text: Date of Application, 31st May, 1887.
Complete Left, 26th Aug., 1887.
Complete Accepted, 4th Oct., 1887.
Improvements in Dovetailing Machines for Open Dovetails.
JOHN ANDERSON 38 Elswick Road Newcastle on Tyne Saw Mill Engineer do hereby
declare the nature of this invention to be as follows:-
Upon a suitable frame or stand, is mounted three or more, horizontal spindles in
adjustable bearings, capable of being placed any desired distance apart, and having
cutters fixed in either end, and driven from a suitable countershaft. On each side of
the main frame or stand is fitted in vertical slides a bracket, carrying a table upon
horizontal slides, upon which the wood is secured, beneath this is a rotating shaft
carrying suitable cams giving vertical motion to the bracket and lateral motion to the
table, so that as the wood rises to the cutters, the desired angle is obtained to form the
pin or tennon on the one piece, and on the other side the holes or tails is formed by
corresponding cutters, the wood rising vertical without the lateral motion, the whole
being adjustale for variable speed and throw so that dovetails of any space and size
can be made.

page_text: COMPLETE SPECIFICATION.
Improvements in Dovetailing Machines for Open Dovetails.
JOHN ANDERSON 38 Elswick Row Newcastle on Tyne Saw Mill Engineer do hereby
declare the nature of this invention and in what manner the same is to bo
performed, to be particularly described and ascertained in and by the following
statement :-
Upon a suitable frame or stand is mounted three or more horizontal spindles in
adjustable bearings capable of being placed any desired distance apart and having cutters
fixed in either end, and driven from a suitable countershaft. On each side of the
main frame or stand is fitted in vertical slides a bracket carrying a table upon hori-
zontal slides upon which the wood is secured. Beneath this is a rotating shaft carrying
suitable cams giving vertical motion to the brackets, and lateral motion to the table, so
that as the wood rises to the cutters, the desired angle is obtained to form the pin or
tennon on the one piece and on the other side the holes or tails is formed by corre-
sponding cutters. The wood rising vertical without the lateral motion. The whole
being adjustable for variable speed and throw so that dovetails of any space and size
can be made.
I will now proceed to explain my said Invention more in detail by reference to
letters and figures on the accompanying drawings.
Fig. 1 is a side elevation of my improved dovetailing machine shewing position of
cutter spindles (), and driving pully B. with the various cams and levers connected
with the automatic feed motions.
Fig. 2. is a front vew on section line 5-6 shewing parts as above with table and
wood X in position for dovetailing.
Fig. 3. is a separate vew of the table shewing the end of the wood X. after being
operated upon.
Fig. 4. shews dovetails cut on the oposite side.
O. is the driving shaft atuated by bevil gearing G. H. and worm F. on shaft E. and
supported in suitable bearings, and has cams J. K, on each end actuating through
rooler P. the arm M. which is pivoted on stud N. and having a slot in which is an
adjustable stud Q. acting on cross bar R. secured to vertical slide bracket S. upon
which the table Y. is fitted. Thus the cam J. rotated in the direction indicated by
the arrow, during the first 3rd of its revolution rises the wood up to the cutters as
they are revolving at a great speed and are paralel in shape for cutting the pins or
tennons X. as shewn in Fig. 3, and the second 3rd of cam J. lowers the wood at the
same rate while the cam K. is operating the lever T. giving a gradual lateral motion
to the table with the wood X, and so forming the slanting sides on the dovetail pins.
When the table is at its lowest point and the wood clear of the cutters, the pawl U is
released and the first 3rd of cam J comes in contact with arm V and it operating on
lever W. with its pawl engaged in the division rack attached to the table sends it
forward for the next cut.

page_text: The opposite side of the machine is worked in a similar way with taper cutters
making the holes or tails in the wood as shewn in Fig. 4, the table rising vertical
without the lateral motion by lever T which is dispensed with. The cams on both sides
are controlled by clutch and lever L. and can be worked independent of each other.
Having now particularly described and ascertained the nature of my said Invention
and in what manner the same is to be performed, I declare that what I claim is
First. In a dovetailing machine the combination of shaft O cam J with vertical
slide bracket S.
Second. Combination of shaft O cam K and lever T pawl U. and table Y.
Thirdly. The adjustable cutter spindles for various spaces and sizes of dovetail,
substantialy as described and for the purpose set forth.