Apparatus for Preparing the Grinding Surfaces of Metal Mills.
Year: 1889

page_text: Date of Application, 22nd July, 1889
Complete Specification Left, 22nd Apr., 1890-Accepted, 31st May, 1890
J
PROVISIONAL SPECIFICATION.
Apparatus for Preparing the Grinding Surfaces of Metal Mills.
We SAMUEL DIXON of the firm of Kendall and Gent of the Victoria Works,
Springfield, Salford, Manchester, in the County of Lancaster, Engineers and Machine
Tool Makers, and HARRY PINSON of Snowhill Mill Works, Wolverhampton, in the
County of Stafford, Mill Manufacturer, do hereby declare the nature of this Invention
to be as follows:-
Our Invention relates to the steel mills or otherwise to the mills having metal
grinding parts constructed according to the type of mill used in the grinding of
coffee, corn, seeds, drugs, and spices. In such mills a conically shaped grinder
revolves within a fixed shell or barrel both parts being cut with grinding furrows as
is well understood. Previously to our invention the said furrows when not produced
by casting have ordinarily been formed by filing. The object of our Invention has
been to produce these furrows by means of cutters so as to obtain increased uniformity
and speed of production. Both the revolving grinding cone and the outer shell or
barrel are of irregular conical formation that is to say they have an irregular or
curved taper which increases the difficulty of cutting the parts which for shortness
we will term the cone and barrel. In the case of the barrel we find it convenient to
employ a reciprocating planing tool but in the case of a cone we can use a mill
which is mounted and actuated in any suitable manner. The cone is carried by a
spindle which has compound movements imparted to it that is to say a traversing
movement for the cut à revolving motion to produce the spiral cut a tilting to form
the profile or irregular cone and in most cases a side movoinent to lessen the depth of
the ent from the small to the larger end of the cone. The said spindle is mounted to
revolve in a part which is hinged to a carriage and is acted upon by a fixed shaper as
the carriage slides to and fro or the shaper might move and act upon a fixed bowl or
part. The said spindle is also parily revolved during the cut to obtain the spiral
formation of the furrow. The said spindle is also rotated by step movements after
the cuts such movements being obtained by means of a dividing plate or motion.
By means of these combined movements the furrows are cut spirally at regular
distances apart around the cone and follow the curved or irregular conical profile of
To obtain the dying out or reduction in depth of the furrows a fourth
inovement is required. The said carriage is mounted to slide upon a second carriage
in a direction at right angles to the direction of movement of the first carriage.
This second carriage is moved as the cut proceeds the direction of movement being
adapted to bring the work more directly below the mill as the eat proceeds so that, if
required the furrow may be cut so as to die out at the larger end of the cone.
practice we obtain this sliding movement of the second carriage by operating upon
the screw whereby the carriage is adjusted the said screw being slid endwise by means
We may
of a lever which is acted upon by the first carriage but this may be varied.
use a planing tool instead of a mill. As ordinarily formed the alternate furrows
merge in the intermediate furrows or otherwise two furrows are cut into one at the
inlet end both in the case of the cone and of the barrel. This formation we effect by
using two shapers the mill or cutter going over the work again with the second
shaper in use the work being rotated to the extent of two furrows after each cut or
the intermediate furrows might be entirely cut by means of the second shaper after
the cutting of the alternate furrows. To avoid having to change the shapers we have
both fixed in position for use and bring either into use by simply tightening the nut
which secures the bowl or stud upon which the shaper operates. The barrel to be
cut is secured to a chuck or carrier upon the end of a spindle which is mounted to
be revolved by step movements imparted by a dividing motion. The spindle can be
the cone.
In

page_text: disengaged from the dividing gear so that it can be revolved to facilitate the correct.
adjustment of the work or if desirable to turn or skim it up inside. The tool carrier
is mounted to swivel and is controlled by a shaper. The said tool carrier is
mounted upon a cross slide which is adjustable upon a main carriage which is
fitted to slide upon a bed toward and from the work receiving motion from a
revolving shaft and preferably from a slotted link as in the case of a quick return
shaping machine. An excentric or cam upon this shaft imparts vibrating movements
to a lover which carries a pawl which acts upon a ratchet wheel and partly turns the
same as the tool returns after each cut or near the end of the return movement of the
tool. The said movement of the ratchet wheel is transmitted through change gearing
and through worm or bevel gearing to the spindle which carries the work.
found it desirable to attach the tool to a hinged tool holder which enables the tool to
free itself when moving back. The depth of cut is determined by the movements
imparted to the cross slide.
Dated this 20th day of July 1889.
We have
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.
COMPLETE SPECIFICATION.
Apparatus for Preparing the Grinding Surfaces of Metal Mills.
We SAMUEL DIXON of the firm of Kendall and Gent of the Victoria Works,
Springfield, Salford, Manchester, in the County of Lancaster, Engineers and Machine
Tool Makers, and HARRY PINSON of Snowhill Mill Works, Wolverhampton, in the
County of Stafford, Mill Manufacturer, 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 and accompanying drawings:-
:-
Our Invention relates to the steel mills or otherwise to the mills having metal
grinding parts constructed according to the type of mill used in the grinding of
coffee, corn, seeds, drugs and spices. In such mills a conically shaped grinder
revolves within a fixed shell or barrel both parts being cut with grinding furrows as
is well understood. Previously to our Invention the said furrows when not produced
by casting have ordinarily been formed by filing. The object of our Invention has
been to produce these furrows by means of cutters so as to obtain increased uniformity
and speed of production. Both the revolving grinding cone and the outer shell or
barrel are of irregular conical formation--that is to say they have an irregular or
curved taper which increases the difficulty of cutting the parts which for shortness we
will term the cone and barrel. In the case of the barrel we find it convenient to
employ a reciprocating planing tool but in the case of a cone we can use a mill or
revolving cutter which is mounted and actuated in any suitable manner.
Our Invention will be most readily understood when described with reference to
the accompanying drawings.
In the said drawings Fig. 1 drawn about one quarter of the full size is a side
elevation and Fig. an end elevation partly in section of the apparatus which we
employ in the cutting of grinding cones Fig. 3 representing parts of Fig. 1 in
section.
In Fig. 1 the cone and the milling cutter are indicated by dotted lines. The cone
is fixed upon a spindle or mandril which is carried by a hollow shaft a within which
is a gripping chuck or tube a¹ which is formed with a split cone at one end and with
a screwed shank a² at the other end.
One end of a cone spindle enters this tube and is securely held therein by
tightening, a nut upon the shank a². The other end of the cone spindle is supported
by means of a centre b which is adjustable upon a swivel frane A in which the
hollow shaft a is mounted. The said hollow shaft has compound movements imparted
to it that is to say a traversing movement for the cut a revolving motion to produce
the spiral cut a tilting.to form the profile or irregular cone and in most cases a side.

page_text: movement to lessen the depth of the cut from the small to the larger end of the cone.
The frame A is binged by one end to a bracket c which is adjustably secured to a
carriage B which is mounted in slides carried by a bed plate d which is mounted to
swivel upon a cross sliding carriage C which is mounted upon the rising and falling
table or table bracket of an ordinary or suitable milling machine. The work can be
adjusted by raising or lowering the table of the milling machine in the ordinary
manner and by swivelling the bed plate d upon the carriage C. The traversing
movement for the cut is obtained by turning the screw shafte whereby the carriage B
is slid in a straight line upon the bed plate d. The revolving motion for producing
the spiral formation of the furrows is obtained by revolving the hollow shaft a as the
work is fed forward. The shaft a is mounted within a second hollow shaft which is
fitted to revolve in a bearing formed partly in the frame A and partly in a removable
cap A. Upon the rear end of the hollow shaft is fixed a worm quadrant f¹ with
which gears a worm which is carried by a shaft g'. This shaft is mounted to
revolve in hollow bushes which project from the inner sides of projecting heads
formed upon the bracket c and serve as hinge pins for the frame A so that the said
frame when being tilted turns upon the axis of the shaft g'. The said shaft is
connected by bevel gearing g² and spur gearing with the screw shaft e. The effect
of this arrangement is that when the screw shift e is turned to traverse the work the
work is also revolved upon its axis so that a spiral cut is produced. The wheels 9³
are changeable so that the extent of the revolving motion can be varied. Upon the
rear end of the hollow shaft a is fixed a toothed dividing wheel a with which engages
a sliding catch a' which is carried by an arm upon the worm quadrant so that the two
hollow shafts are compelled to turn together. After the completion of a cut the
catch a is withdrawn and the dividing wheel is turned so as to rotate the shaft a
within the shaft f to the extent of one two or more teeth in the dividing wheel
according to the relation between the number of teeth in such wheel and the number
of furrows which are to be cut upon the cone as will be well understood. The
dividing wheel can be changed for wheels having different numbers of teeth as may
be required. The frame A being hinged at one end requires support. A. bowl is
mounted on a stud which is adjustably secured to the side of the frame A. The said
bowl rests upon a profile rail or shaper which is adjustably secured to the bed
plate d. As the carriage B is traversed to and fro the bowl runs upon the profile rail.
By raising or lowering the bowl upon the frame A the axis of the shaft a can be
more or less tilted to suit the proportions of the cone to be cut and by making the
upper face of the profile rail of the required for the inclination of the axis of the
said cone can be varied during the cutting of a furrow. The cones as ordinarily
produced have the furrows curved inward toward the axis at the smaller end of the
conc. Supposing the cut to be made from the smaller to the larger end of the cone
as in the example the profile rail or shaper would be curved and prepared to such a
form as that the inclination of the axis would be reduced as the cutting proceeded
such reduction of inclination being in some cases most rapid at the commencement of
the cut and being reduced as the work traversed below the mill. The shaper rail can
be changed so that by using an appropriate shaper any required form of cone
can be cut. As ordinarily formed the alternate furrows merge in the intermediate
furrows or otherwise two furrows are cut into one at the smaller end of the cone.
This formation is effected by using two shapers the mill or cutter going over the work
again with a second shaper in use the work being rotated to the extent of two
furrows after each cut or the intermediate furrows are entirely cut by means of the
second shaper after the cutting of the alternate furrows. To avoid the changing of
he shapers the two shapers required are fixed one on each side of the frame A so that
t is only necessary to raise and lower the bowls into position to run upon the shapers
lternately as required. The merging of the furrows can also be effected by
ncreasing the revolving motion of the hollow shafts fa when cutting two furrows into
After the furrows had been cut all round the cone the gearing g² would be
banged so as to produce a quicker spiral cut and the work would be gone over again
or a suitable distance from the smaller end of the cone turning the work to the
ne.

page_text: extent of two furrows after each cut as aforesaid. We prefer to traverse the
carriage B selfactingly to effect the cutting of the furrows. In the example a worm
wheel is mounted upon one end of the screw shaft e and is actuated by means of a
worm which would be driven by a shaft or a band and pulley from a suitable part
of the milling machine to which our apparatus would be applied. The said worm
wheel gives motion to the screw shaft through a clutch which can be engaged and
disengaged by means of a sliding rod which can be acted upon from the other end
of the carriage by means of a hand lever . When a furrow has been cut completely
or as far as is required a sliding movement of the rod disengages the worm wheel and
the carriage can be slid back by turning the hand wheel e. The furrows are cut
spirally at regular distances apart around the cone and follow the curved or irregular
conical profile of the cone. To obtain the dying out or reduction in depth of the
furrows a fourth movement is required as aforesaid. This movement we obtain by
sliding the whole of the apparatus shewn in Fig. 1 upon the rising and falling table
of the milling machine which is in part indicated in section by j in Fig. 1. The
carriage C is moved upon this table for the adjustment of the work by turning a
screw shaft and the sliding of the said carriage during the cutting of a furrow
might be effected by turning the same screw to the required relative extent. In
practice however we have obtained the required movement by sliding the screw shaft
end wise in its bearings. The means which we have adopted for this purpose are
indicated in Fig. 4. The shorter arm & of a lever is coupled to the screw shaft so
that the connection does not interfere with the rotation of the screw. The said lever
is mounted to turn upon a fixed fulcrum at A4 and the longer arm 2 of the lever is
acted upon by a part which is attached to the carriage B so that as the said carriage
slides to and fro the lever is turned upon its fulcrum and slides the screw shaft
end wise. A bowl upon the arm of the lever runs in a slot in a plate / which is
pivoted at to a second plate 12 which is adjustable upon a slide m which is fixed to
the carriage B as seen in Fig. 1. The plate can be set and fixed at varying angles
upon the plate the angle of the slot in the plate as compared with the line of
motion of the carriage B determining the extent of end wise movement of the screw.
shaft and as a consequence the lateral movement of the work during the cutting of
a furrow. By the combination of the four movements namely the straight traverse
of the carriage B; the varying of the inclination of the axis of the work; the rotation
of the work, and the sliding of the carriage C we are enabled to cut the required
furrows upon the cone. It will be seen that bars m³ are attached to the sides of the
hend in which the hollow shafts af revolve. We attach weights or a load to these
bars in order to steady the frame A but if not considered to be necessary the use of
such weights may be dispensed with.
Figs. 5 and 6 in Sheet 2 illustrate the machine we have devised for cutting the
furrows in the barrel Fig. 5 being a side elevation and Fig. 6 a plan of the machine
which is drawn to a scale of about one and a half inches to the foot. In the said
Figs. n is a face plate to which the work is secured as indicated by the dotted lines.
Any suitable chuck for holding the work may take the place of the said face plate or
be secured to the same. The face plate is fixed upon a spindle n' which is fitted to
revolve in a headstock N and is actuated by a worm o which gears with a worm
wheel which is fixed upon the tail end of the spindle. The worin o is fixed upon a
shaft of which is connected by change gearing p with a shaft y which carries a ratchet
wheel. Upon the shaft q is mounted a pawl lever q which is connected by a link r
with a levers which is fixed upon a rocking shaft s which is actuated in manner to
be hereinafter described. As the shaft s rocks to and fro the pawl carried by the
lever turns the wheel q' whereby the spindle is rotated to an extent which is
arranged to be equal to the pitch or central distance between the furrows which are
to be cut in the barrel. The headstock N is fixed to a bed T upon which is mounted
a sliding carriage U which is fitted with a cross slide u. Upon this cross slide is
mounted a tool carrier u which is centered upon a hinged pin or stud u³ which is
fixed to the cross slide u¹. In the said tool carrier is fixed a tool holder u' in which
the cutter is secured. The carriage u is connected by an adjustable link with a

page_text: slotted link which is mounted to vibrate upon a stul and is actuated by a crank-
pin and by suitable gearing and by a belt pulley in a similar manner to-the-
actuating motion of an ordinary shaping machine. It will be seen that as the link v'
vibrates the carriage U will be slid to and fro upon the bed T and will have a slow
forward movement toward the face plate for the cut and a quicker return movement..
Upon the bed T is fixed a shaper bed w upon which is fixed a shaper plate w' which.
is formed with two curved shaper slots. The tool carrier u is formed with a tail
piece which carries two studs u upon which are mounted anti-friction bowls.
which run in the two curved slots in the shaper plate. The said studs pass
through slots in the tail piece which are long enough to give the studs so much play-
to and fro as that if either stud be not tightly fixed the shaper plate will have
no effect upon the tool carrier. The two shaper slots vary in form and either one..
can be brought into use by tightening the nut upon the stud which passes into
such slot. A crank pin which is fixed to the spur wheel v is connected by 'a
rod with a lever which is fixed upon the shaft s' so that the said shaft makes
a to and fro rocking movement for each to and fro sliding movement of the
carriage U. The cross slide is adjusted upon the carriage U so as to bring the tool
into cut and to regulate the depth of cut by turning a screw y.
When the barrel to.
be cut has been fixed to the face plate or been chucked as the case may be and the
carriage U been set in motion the tool is brought into cut and as it moves inward..
takes a cut along the interior of the barrel. As the tool moves inward the bowls u'
traverse the curved slots in the shaper. One of these slots is designed to control the
action of the tool when cutting the furrows in the first instance the other slot being..
adapted to cause the tool to merge two furrows into one at the inlet end of the barrel...
It will be seen that the bowl which is upon the stud which is screwed up tight will be.
acted upon the other being left loose to accommodate itself to the curved slot in the.
shaper. As the tool moves: inward along the interior of the barrel the tool carrier is
rocked upon the axis at us by the action of the shaper plate and the tool is thereby..:
moved to and fro horizontally to the extent required to enable it to follow the contour.
of the interior of the barrel. As the tool retires the ratchet wheel q is rotated so as
to cause the work to rotate to the extent of the. distance between two furrows. The
cuts are repeated until the work has made an entire revolution when if necessary the..
tool is set in a little by turning the screw y and another cut or two or more successive
cuts is or are taken along all the furrows. The nuts on ' are respectively slackened-
and tightened so as to put the other shaper slot into action and cuts are taken to cut.
two furrows into one at the inlet end of the barrel as aforesaid. For these cuts the
gearing is changed so as to cause the work to be turned to the extent of two furrows
after each cut or the parts are adjusted so that the ratchet pawl shall take two teeth-
or twice the number of teeth after each cut as compared with the first operation.. The
spindle n which carries the work is driven through a coupling clutch which can be
tightened up by means of a bolt z¹. When the said bolt is slackened the face plate
and spindle can be turned for the fixing and adjustment or removal of the work with-
out turning the worm wheel 72². If preferred the tool carrier might be mounted.to
turn upon a horizontal or inclined axis instead of upon a vertical axis. No attempt
has been made to represent the exact forms of the shaper slots and surfaces in-the
drawings as these will vary and must he made to suit the peculiarities of the work
which is to be operated upon.
We do not confine ourselves to the use of slotted.
shapers in the barrel cutting apparatus. We might employ a reciprocating, cutting.
tool in the place of the mill for cutting the cones but we have considered the mill to
be the most suitable for the purpose.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. The combination of paris constituting the apparatus for cutting furrows in steel
or metal mill cones and barrels substantially as set forth and indicated.
2. In apparatus for furrowing metal mill cones the swivel or tilting frame provided

page_text: with a revolvable shaft or head to carry the work and mounted upon a sliding
carriage and the shaper rail or rails for acting upon such swivel frame substantially as
set forth and indicated.
3. In apparatus for furrowing metal mill cones the hollow shaft for carrying the
work provided with a dividing plate and seated within another hollow shaft which is
acted upon by parts which turn such hollow shaft during the cutting of each furrow
so as to produce a spiral cut substantially as set forth.
4. The carriage adapted to slide upon a bed which can be applied to a milling
machine and the connection by means of gearing of the screw shaft actuating such
carriage with a hollow shaft which is concentric with the work and which when
turned turns the work substantially as and for the purpose set forth and indicated.
5. The combination of the carriage having a traversing movement with the under
carriage having a traversing movement upon the table or bed of a milling machine in
the direction of the axis of the mill or thereabouts and with a swivel frame to carry
the work having a tilting movement imparted by a fixed shaper and with parts which
hold the work and which can be revolved upon the axis of the work substantially as
and for the purpose set forth and indicated.
6. The hollow shaft a provided with the hollow chuck shaft a and with the
dividing plate a³ in combination with the hollow shaft provided with the arm which
carries the catch a substantially as and for the purpose set forth and indicated.
7. The swivel frame A carrying the parts which hold the work and mounted to
swivel upon the axis of the worm shaft whereby a rocking motion is imparted to such
parts substantially as and for the purpose set forth and indicated.
8. The screw shaft j¹ mounted to slide endwise and to engage with the lever k k²
which is arranged to be acted upon by the carriage B through adjustable parts so as
to move the parts which carry the said carriage upon the table or bed of a milling
machine substantially as and for the purpose set forth and indicated.
9. In apparatus for cutting the furrows in the interiors of the barrels of metal
grinding mills a reciprocating cutting tool in combination with a face plate or chuck
for holding the work acted upon by parts which turn such face plate or chuck a
fractional part of a revolution after each cut of the tool substantially as set forth.
10. In apparatus for cutting the furrows in the interiors of the barrels of metal
grinding mills the tool carrier mounted to swivel upon a reciprocating carriage and
acted upon by a fixed shaper adapted to control the action of the cutter to suit the
contour of the grinding surface of the work substantially as set forth.
11. The shaper plate formed with two slots differing in form in combination with
a swivel tool holder carrying two bowls or studs to work in such slots with means for
bringing into use either slot as required substantially as and for the purpose set forth
and indicated.
•
12. The carriage mounted to slide to and fro upon a bed the adjustable cross slide
carrying a swivel tool holder and the stationary shaper in combination with parts for
imparting to and fro quick return reciprocations to such carriage substantially as and
for the purpose set forth and indicated.
13. The spindle mounted in a headstock and carrying a face plate or chuck the
worm gearing for actuating such spindle the ratchet wheel connected by change
gearing with such worm gearing and the lever carrying a pawl to engage with such
ratchet wheel and receiving a vibrating motion in relation to the movements of a
reciprocating carriage upon which is mounted a tool holder substantially as and for
the purpose set forth and indicated.
Dated this 21st do of Anvil 1800
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.