IMPROVEMENTS IN OR RELATING TO SLOTTING OR KEY-SEATING MACHINES
Year: 1884

page_text: I JOHN HARPER the younger, of Aberdeen in the county of Aberdeen,
Commission Agent and Engineer do hereby declare the nature of my said invention
for IMPROVEMENTS IN OR RELATING TO SLOTTING OR KEY-SEATING MACHINES
to be as follows:-
This invention has for its object a method of cutting or sawing grooves or key
beds in shafts pulleys and the like without moving the article to be cut or the
table of the machine on which it rests:
I use pulleys with slow and fast gearing, crank pin on revolving disc or its
equivalent, eccentric and slide as in ordinary slotting machines with fast and slow
speeds. The tool or saw however instead of being rigidly fixed in the holder is
simply pivoted therein and is free to turn in one plane only-the cutting plane.
The end of the saw or shank of the tool is guided by a guide travelling in slides
or otherwise. As the tool cuts the guide is slowly advanced by any suitable
machinery such as a rack and pinion, and this puts a feed on the tool.
It will be seen from this that ordinary key bed slotting machines could be
adopted to this process by simply pivoting the tool so as to oscillate in the cutting
direction and applying a travelling guide to the shank of the tool or to a
continuation of the back of the tool beyond the cutting edge.
Dated this first day of January 1884

page_text: I, JOHN HARPER, the younger, of Aberdeen in the County of Aberdeen,
Commission Agent and Engineer do hereby declare the nature of my said
invention for "IMPROVEMENTS IN OR RELATING TO SLOTTING OR KEY SEATING
MACHINES" and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention has for its object a method of cutting or sawing grooves or key
beds in shafts, pulleys, and the like without moving the article to be cut or the
table of the machine on which it rests.
I use pulleys with slow and fast gearing, crank pin on revolving disc or its
equivalent, eccentric and slide as in ordinary slotting machines with fast and slow
speeds. The tool or saw however instead of being rigidly fixed in the holder is
simply pivoted therein, and is free to turn in one plane only-the cutting plane.
The end of the saw or shank of the tool is guided by a guide travelling in slides or
otherwise. As the tool cuts, the guide is slowly advanced by any suitable
machinery such as a rack and pinion, and this puts a feed on the tool.
.
It will be seen from this that ordinary keybed slotting machines could be
adapted to this process by simply pivoting the tool so as to oscillate in the cutting
direction, and applying a travelling guide to the shank of the tool or to a
continuation of the back of the tool beyond the cutting edge.
Referring to the drawings:
Fig 1 is a plan view of table and upper parts.
Fig 2 plan view of pedestal or frame and lower part.
Fig 3 is a sectional elevation of entire machine.
Fig 4 sectional elevation at right angles to that shown in Fig 3 and with table
removed.
Fig 5 elevation of machine in the position shown in Fig 3.
In these, A is the driving shaft. B B fast and loose pulleys thereon.
CC gearing for reducing speed if required. I need not describe this as it is a very
common and well known device with slotting machines and lathes, D crank.
E connecting rod. F crosshead sliding in slides or cheeks G. H saw. As stated
in the provisional specification, a single slotting tool could be attached to a bar in
place of using a saw, the effect would be the same as if the saw had a single tooth.
1 I framework of machine. J table. K adjusting fences or clamps of any ordinary
description for holding the pulley on the table in position. L standards fixed to
the table with series of washers and nut; these support the guide bar M at any
required height. It is often desirable to have a considerable amount of spring,
hence why mere bolts are used, but, if necessary, firm supports can be used instead.
M guide bar. This bar is supported on the standards L L which are placed in any
of the grooves N N N. The object of having several grooves is that if the cutting
is too deep for the travel of the saw with the bar M in one position, it can be
taken off and placed with the standards in the next grooves. The number of
washers on L, above and below M respectively, regulate the height of bar M above
the table, so as to vary it for different heights of the articles to be cut.
drawing is that of a machine designed for cutting shallow key beds mostly, but
where deep cuts are required the slot P in the table must be lengthened. Q is a
guide on bar M to guide the saw, N₁ adjusting screw thereon. This guide slides
on bar M and has teeth as shown, into which gear the teeth of a segmental wheel
The

page_text: on handle R. R is the feed handle. In place of this feed motion a screw and
hand wheel or any other ordinary feed motion could be fixed on bar M.
The mode of action is as follows:-
The pulley being placed in position on the table the saw is adjusted against it by
screw N. The machine is then set a going, either with fast or slow speed, and a
steady pressure brought to bear on feed handle R, till the slot is sawn deep enough.
By this means a slightly sloping key bed is cut without having to tilt the pulley, a
great advantage.
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:-
1st. The manufacture and use of slotting or key seating machines, with the
reciprocating tool or tool holder held in guides at one end, so as to reciprocate
truly, and having its free end fed forward so as to cut the key bed without moving
the article cut, substantially as described.
2nd. In a slotting or key seating machine, a tool or saw pivoted in its
reciprocating holder at one end so as to be only capable of moving in one plane,
and guided at a distance from that tool holder by a feeding device, so as to be fed
forward in that plane while reciprocating.
3rd. The method of slotting or key seating by machinery which consists in
pivoting the tool so as to reciprocate in a given direction, and be capable of
oscillating in the cutting direction, and applying a travelling holder back or guide
to the shank of the tool, or to a continuation of the holder back, or shank beyond
the cutting edge, substantially as described.
4th. The key seating machine as a whole constructed and arranged, substantially
as herein described and illustrated.