Improvements in Dove-tail Cutting Machines and the like.
Year: 1896

page_text: Date of Application, 24th Jan., 1895
Complete Specification Left, 24th Oct., 1896-Accepted, 23rd Jan., 1897
PROVISIONAL SPECIFICATION.
Improvements in Dove-tail Cutting Machines and the like.
I, JAMES READ RICKARD, of 143, Kennington Road, London, in the County
of Surrey, Engineer, do hereby declare the nature of this invention to be as
follows:
This invention relates to certain improvements in the dove-tail cutting machine
specified in my prior Patent No. 1124 of 1895, the object of which is first, to
render the machine more automatic, and secondly to provide a simple device for
cutting the parts of mitre dovetail joints.
According to the first part of my invention I mount the axle adapted to carry
the cutter in a long bearing formed on or fixed to a slide mounted in a suitable
saddle plate adapted to rotate in an annular bearing carried by the frame of the
machine, the face of the said plate being slotted to allow of the movement of the
slide carrying the axle bearing at the same time that the plate carrying it is free
to rotate in the bearing carried by the frame. The slide carrying the cutter axle
is adapted to be moved up and down either by a hand screw and fly wheel or by a
lever and links, preferably by the former.
On to the back of the bearing carrying the rotating saddle plate is fixed a cam
plate having inclined surfaces against which the bearing of the cutter axle or a
roller mounted thereon bears, as the slide carrying it is traversed up and down,
thus causing the cutter to travel at the required angle both on the up and down
stroke to cut both sides of the female part of the dovetail. An elastic stop or
finger is provided to engage with indents in the rotating plate to hold it in both
positions during the time that the cutter is traversing the piece of wood
being cut.
To traverse the table on which the wood is fixed to the required distance for
the next dovetail motion is obtained from the rotary movement of the rotating
saddle plate by any convenient device such as the following:-A bell-crank lever
is pivotted to the rotating plate against which the bearing of the cutter axle or a
roller mounted thereon engages as the slide carrying the cutter axle reaches the
ends of its stroke and so imparts motion to the table by means of a pawl connected
to one end of the bell-crank lever and adapted to engage with the teeth of a rack
on the table, the attachment of the pawl to the bell-crank lever being adjustable
for the purpose of varying the traverse of the table.
The axle for carrying the cutter is made hollow and its front end is coned to
receive the tapered shank of the cutter which is drawn up into the end of the
axle by means of a threaded rod adapted to be passed through the axle from the
opposite end thereof and to be threaded into the screwed end of the cutter.
To cut mitre dovetails, the traversing table carries a light frame or guide which
is adapted to hold the wood at the correct angle for the cutter to cut the required
dovetail.

page_text: Improvements in Dove-tail Cutting Machines and the like.
I, JAMES READ RICKARD of 143, Kennington Road, London, in the County of
Surrey, Engineer, 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 certain improvements in the dove-tail cutting machine
specified in my prior Patent No. 1124 of 1895, and it consists of a device for
automatically throwing the slide carrying the revolving cutter over from one angle
to another at the top and bottom of the stroke of the slide, of a device for
automatically traversing the table carrying the wood to be cut, and of a frame or
guide for holding the wood when mitre dovetails are to be cut, the object being to
render the machine more automatic, and to enable mitre dovetail joints to be made
more rapidly and perfectly.
In the accompanying drawing
:-
Figure 1 is a view in front elevation of a machine embodying my invention.
Figure 2 is a view in side elevation thereof-partly in section.
Figure 3 is a view in plan thereof.
Figures 4, 5, 6 and 7 are views in back elevation showing the device for
automatically reversing the angle of the slide carrying the cutter.
Figure 8 is a broken view in front elevation showing the automatic gear for
moving the table carrying the wood and
Figure 9 is a view in side elevation thereof showing also the frame for holding
the wood when mitre dovetails are to be cut.
Throughout the views similar parts are marked with like letters of reference.
The machine consists essentially of a table A mounted to slide transversely on
a bed A¹ carried by a saddle A2 adapted to slide at right angles to the table A on
a bed A³ carried by a plate A' mounted on the stand or pedestal A5 of the machine.
The table A is operated by means of a rack and quadrant through the hand
wheel B, the rack a being formed on or fixed to the table, and the quadrant b being
mounted on a suitable spindle C carrying the hand wheel B the spindle being
mounted in a bearing bracket C₁ attached to the bed A. The saddle A2 is
operated by means of a hand wheel, screwed spindle and nut in a manner similar
to the slide rests of lathes. Immediately behind the table A is a saddle D mounted
to slide on a bed plate E adapted to rotate or rock in an annular bearing in a
bracket A carried by the stand or pedestal A³ to which end it is provided with
an annular bush E₁ preferably made in two parts for convenient construction.
The saddle or slide D carries a bearing F in which is mounted a spindle G adapted
to be driven by means of a pulley G' mounted on its back end, motion being
communicated to the said pulley by a band from any convenient source of power,
a suitable tensioning device of any known construction being used for keeping the
driving band taut in any position that the pulley G¹ may assume. The spindle G for
carrying the cutter bit H is made hollow and its front end is coned to receive the
tapered shank of the cutter which is drawn up into it by means of a threaded
rod g adapted to be passed through the axle from the opposite end thereof and to
be threaded into the screwed end of the cutter bit by means of the milled head g
as shown in Figure 2 of the accompanying drawings. The saddle or slide D is
traversed up and down by means of a screw M working in a threaded eye m carried
by the bracket E³ formed on or fixed to the plate E and operating the saddle or
slide D through an axial joint with a bracket d formed on or fixed to the saddle
or slide D, the screw M being operated by a hand fly wheel M' as shown. As an

page_text: alternative the saddle or slide may be traversed by means of a pivotted hand
lever but I prefer to use a screw and hand wheel as herein before described.
So far the construction presents no novel features. I will now describe the
improvements constituting the present invention :-
On the bearing F are formed or fixed two arms f carrying rollers J and J
adapted to engage with two inclined planes and k¹ formed in an annular disc K
fixed to the rear bearing bracket A. One of the inclined planes k is shorter than:
the other and its ends form stops 2 and 3 against which the roller J engages and
causes the plate E carrying the cutter slide D to rock over to its other angle.
This automatic action will be clear on reference to Figures 4, 5, 6 and 7 of the
accompanying drawing. In Figure 4 the cutter slide is at the bottom of its travel
on rotating the hand wheel M¹ the slide D will be caused to travel on its up stroke
at the angle shown being guided by the roller J bearing against the inclined
plane. As the slide D approaches the top of its travel (position shown by
Figure 5) the roller J engages with the stop and causes the slide to be thrown'
over to its other angle (position shown by Figure 6). The hand wheel M¹ is then
rotated in the other direction and the slide D is caused to travel downwards at the
opposite angle, being guided by the roller J bearing against the inclined plane k:.
As the slide D approaches the bottom of its travel (position shown by Figure 7).
the roller J engages with the stop k² and causes the slide to be thrown over to its
other angle ready for its up travel as shown by Figure 4. The length of the
travel of the slide before the roller J comes into contact with the stops and ³
will obviously be determined by the greatest thickness of wood it is required.
to cut.
Instead of guiding the slide D by means of the inclined planes arranged on the
aunular disc fixed on the rear of the bearing bracket A' it may be guided by bearing
direct against projections such as 4, 4, on the front of the bearing bracket as shown!
by Figure 1.
To prevent the accidental moving of the slide during the part of its travel when
the cutter is at work the plate E is held in position by means of a round nosed?
spring controlled pawl E mounted on the bracket A' and engaging with shallow
depressions e in the rounded bottom of the plate E, the centre depression being
used to retain the slide D in its central position for cutting the male portions of
the dovetail.
To vary the angle of the dovetail, either another plate K is substituted having
the planes k and k¹ cut to the required angle, or the parts of the said plate forming
the planes may be made adjustable in any suitable manner.
When it is desired to traverse the table A automatically the positions of the
table A, bed A¹, saddle A2 and bed A³ are reversed as shown by Figure 9 the
table A being mounted to slide on a transverse bed A carried by a saddle A
sliding on a longitudinal bed A³ carried by the plate A adapted to be mounted on
the top of the stand or pedestal A. The rack a is therefore formed on or attached
to the saddle A2 and the bearing, bracket C' is carried by the stand or pedestal A³.
On to the side of the saddle A2 next to the bracket A is formed or fixed
a second rack a with which a pawl n carried by a lever N engages. This.
lever N is operated by an arm d¹ carried by the bed plate E through a pin d
adapted to engage with a slot in the lever N. By allowing the position of
the pin d to be adjusted with respect to the arm d¹ the traverse of the
table A can be varied as desired. When the point of pivot of the lever N
is between the end carrying the pawl and the slot with which the pin d
engages the table A is traversed when the cutter is at the bottom of its travel.
To traverse the table when the cutter is at the top of its travel the point of pivot.
of the lever N would be below the slot with which the pin d' engages.
To cut mitre dovetails a frame such as O is mounted on the table A as shown.
by Figure 9, the front face of the frame which receives the wood being at an angle
of 45° with the table A. A stop P is provided on the bottom edge of the frame O

page_text: against which the edge of the piece of wood in which the mitre dovetail is to be
cut rests.
The pieces of wood to be cut are clamped to the table A or to the frame O by
any suitable device, preferably by that described in the Specification of my prior
Patent No. 1124 of 1895.
I wish it to be particularly understood that I do not limit myself to the precise
details of construction herein before described and illustrated by the accompanying
drawings, but that I hold myself at liberty to make such changes and alterations
as fairly fall within the spirit and scope of my invention.
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 improvements in dove-tail cutting machines as hereinbefore set
forth.
(2.) In a dovetail cutting machine having a revolving cutter or bit, mounting
the bearing carrying the said cutter or bit on a traversing slide the bed of which
is mounted in a bearing so that it can oscillate for the purpose of varying the angle
at which the traversing slide moves, and causing the said slide to move over
automatically from one angle to the other both at the top and at bottom of its
travel, as and for the purpose set forth.
(3.) In a dovetail cutting machine having a rotating cutter or bit carried by a
traversing slide adapted to oscillate in a bearing so that the said slide can move at
the necessary angle, the mechanism hereinbefore described for causing the traversing
slide to move over automatically from one angle to the other, and for traversing
the table carrying the wood to be cut after each reciprocation of the slide carrying
the cutter or bit, as set forth.
(4.) In a dovetail cutting machine having a revolving cutter or bit, a frame such
as O having a stop such as P at its lower end for the purpose of cutting mitre
dovetails.
(5.) In a dovetail cutting machine, the combination of a revolving cutter or bit
carried by a traversing slide the saddle or bed of which is mounted so as to
oscillate, of the mechanism for guiding the traversing slide and automatically
throwing it over from one angle to the other at each end of its travel, of the
mechanism for automatically traversing the travel carrying the wood to be cut,
and of the frame for cutting mitre dovetails, as and for the purpose hereinbefore
set forth.
d this 24th day of October 1896.
ROBERT E. PHILLIPS, Assoc. M. Inst. C.E., M.I. Mech. E.,
Consulting Engineer and Patent Agent,
70, Chancery Lane, London, W.C., Agent for the Applicant.