Improvements in Edge Runners or Vertical Mill-stones.
Year: 1892

page_text: Date of Application, 19th Sept., 1892-Accepted, 22nd Oct., 1892
COMPLETE SPECIFICATION.
Improvements in Edge Runners or Vertical Mill-stones.
I, HENRY MANTEY, Mechanical Engineer of the Ferrocarril Mexicano, a
citizen of the United States and resident of Orizava, in the State of Vera Cruz
and Republic of Mexico, 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 improvements in that class of grinding mills which
have two or more vertical mill-stones arranged on horizontal axles and adapted to
rotate around a common central shaft through which the power is applied for rotating
them.
And the invention consists first in arranging the axles upon which the mill-stones
are mounted in the same horizontal plane of rotation, but in different vertical planes
which are normally inclined forward with relation to the radius of revolution, and
second in providing means for adjusting the angle of inclination to correspond with
the rate of revolution.
The object of this new arrangement of axles is to counteract the tendency of
the mill-stones to press outwardly upon their bearings under the influence of the
centrifugal force and thereby to obtain a decrease of the wear of the axles and their
bearings.
In order that my invention may be fully understood, I will first describe the same
with reference to the accompanying drawings and then more particularly point out
in the claims what I deem as new therein.
In said drawings:
Figure 1 is a front edge view of a mill representing the preferred embodiment of
my improvement, the stones being mounted upon adjustable crank-axles and the
pan being shown in section.
Figure 2 is a top plan view of the same, the vertical operating shaft being shown
in section.
Figure 3 is a detail top elevation of a modified arrangement for adjustably
connecting the crank-axles to the operating shaft.
Figure 4 is a detail edge view of the same.
Figures 5, 6, and 7 are detail views of a further modification showing simple
axles pivotted to the boxing and having set screws for adjusting their position.
Figures 8 and 9 are detail top and side elevations of another form of my
improvements in which the axles are pivotted to the boxing.
Figures 10, 11, 12, and 13 are detail top and side elevations of further
modifications.
Figure 14 is a diagrammatic representation of a mill employing four stones to
which my improvement can also be applied.
Figure 15 is a diagrammatic view illustrating the action of my improved mill.
It will be observed that in each form of my invention shown in the drawings, the
axles upon which the stones are supported are in the same horizontal plane of
rotation but in different vertical planes, which vertical planes do not pass through
the central operating shaft but are forwardly inclined with relation to the radius of
rotation. This arrangement of the axles gives the stones an inward tendency and
counteracts the centrifugal force so that the bad effect therefrom is reduced to a
minimum and the stones and bearings will last a much longer time.
In Figures 1 and 2 which represent the preferred embodiment of my inven-
tion, A, A, are the vertical mill-stones operating as usual in the pan A', and B, B,
are adjustable crank-axles having the inner journal ends b, b, which are
mounted in adjustable boxes presently to be described, and the outer journal

page_text: ends, b; b, upon which the mill-stones A, A, are mounted as shown. C is the
central vertical operating shaft mounted in suitable bearings and driven by suitable
gearing. D is a cross-beam keyed to the shaft C and formed with curved
portions d, d', extending respectively from points near the centre of the opposite
edges of the beam to the outer ends thereof. The ends of the beam D are formed
with horizontal cross-cuts or slots for the reception of the adjustable journal boxes.
E, E are the adjustable journal boxes in which the inner journal ends b, b, of the
crank-axles are journalled. These boxes fit in the cross-cuts of the beam D and
are formed with upper and lower curved flanges e, e¹, which bear against the curved
portions d, d¹ of the cross-beam. Suitable bolts extend from the curved faces of
the cross-beam and pass through slots in the curved flanges e, e' of the boxes E, E'
and are held therein by the nuts F, F. It is obvious that by loosening the nuts F, F',
the boxes E, E' carrying with them the crank-axles, can be adjusted on the curved
faces of the cross-beam so as to change the inclination of the outer bearing ends b¹, 61
of the crank axles B, B, to the radius and tangent of the circle of revolution.
In Figures 3 and 4, C is the vertical operating shaft. G is the cross-beam keyed
to the shaft C, and H, H¹, are crank axles adjustably connected to the opposite
ends of the cross-beam G. J, J, are journal boxes having flat grooved under
faces j, j, which rest on the upper face of the cross-beam G near its opposite ends
and are adapted to slide thereon. The inner journal ends h and h¹ of the crank-
axles H, H', are journalled in the boxes J, J, and retained therein by lynch-pins K.
9, 9, are vertical longitudinal slots arranged centrally in the ends of the cross-bar G,
and, gare set screws passing through said slots and engaging screw-threaded
openings in the under sides of the journal boxes J, J. By unscrewing the set
screws the boxes J, J, carrying with them the crank-axles, may be adjusted longi-
tudinally on the cross-beam G which changes the angle of inclination of the outer
axle ends of the crank-axles (upon which the mill-stones are journalled) to the
radius and tangent of the circle of revolution as in the preferred form of my
improvement.
In Figures 5, 6, and 7, C is the central vertical operating shaft to which is keyed
an oblong boxing L having flaring mouths or sockets 1, 1, at its opposite ends in
which the enlarged ends m, m, of the axles M, M, are horizontally pivotted by
means of pivot pins m', m', N, N, and N', N¹, are set screws operating in the side
walls of the mouths or sockets 1, 1, at the opposite ends of the boxing L, and
adapted to engage the enlarged ends m, m, of the axles for regulating the angle of
inclination of the axle with relation to the radius of revolution. By respectively
unscrewing and screwing up the set screws at the opposite sides of the sockets 1, 1,
it is obvious that the axles will be moved on the pivots m', m' and their position
changed.
In Figures 8 and 9 I have shown a somewhat simpler arrangement in which the
mill-stone axles are also adjustably pivotted to their boxing. C is the vertical
operating shaft, and O is the boxing keyed to the shaft. The boxing is formed
with projecting shoulders o, o, and slots o¹, o', in the ends and shoulders. The
axles P are formed with right-angled extensions p, p, and are pivotted at Q, Q, in
the slotted ends of the boxing O so that the extensions p, p, will normally rest in
the slots of the shoulders o, o. R, R, are screw bolts passing through corresponding
perforations in the shoulders o, o, and projections p, p, by means of which the axles
can be adjusted on their pivots.
In Figures 10 and 11 the cross-beam S is formed with oppositely extending flat
faces to which the enlarged ends t, t, of the axles T are secured by means of
bolts s, s, passing through perforations in both of them. Plates T₁, T' are placed
between the ends of the axles and cross-beam to regulate the angle of inclination of
the axles, a change in the thickness of the plates changing the inclinations.
In Figures 12 and 13, the cross-beam U is keyed to the operating shaft C and
formed with longitudinal ridges u, u. The axles V, V, are formed with enlarged
ends u, v, having longitudinal grooves v¹, v¹ corresponding to and fitting over the
ridges u, u, of the cross-beam. The adjacent faces of the cross-beam Ŭ and axle

page_text: ends r, r, are serrated as shown so as to more intimately engage each other. Screw
bolts projecting from the opposite faces of the cross-beam and passing through
corresponding slots in the ends of the enlarged axle-ends r, v, are held in any
adjusted position therein by the nuts u', u'. By loosening the screw nuts u³, u¹ and
moving the axles on the cross-beam it is clear that the inclination of the axles with
relation to the radius of revolution can be regulated.
In Figure 14 I have shown my improvements applied to a mill employing four
mill-stones. Each axle can be adjustably supported on the boxing in any suitable
manner such as shown. The axles are shown with enlarged ends which are adjust-
ably connected to the boxing by means of set screws.
It is quite obvious that my invention would apply equally as well to that form of
vertical mill in which the stones are rotatably supported on a suitable axle which
is held in fixed bearings, and the pan is made to revolve under the stones. This is
of course an equivalent arrangement and the action of the stones is substantially
the same.
Figure 15 represents the action of the form of mill shown in Figures 1 and 2.
The change in position of the axles B is indicated by dotted lines. The lines 1
and 4, indicate the radial changes in the position of the mill-stones, and the lines 2,2,
represent the tangential change in the direction in which the resistance on the
working faces of the stones is exerted. The stone A when otherwise uninfluenced
tends to move at right angles to the journal end of the axle as indicated by the
arrow 3, and as the line of direction constantly gets nearer to the centre of rotation
until it crosses the radius 4 which is parallel to the journal end b', it is clear that
the stone alone has an inward tendency which is increased by the direction of the
resistance.
The action of my improved mill may be explained as follows
The resistance on the working faces of all cylindrical vertical mill-stones is
exerted in a direction parallel with the tangent of the circle of revolution, and the
stones tend to move in the same direction. In the common form of vertical mills
the axles upon which the stones are mounted extend radially from the vertical
operating shaft, and consequently the resistance on the working faces of the stones
is exerted at right angles to their axles and the tangential tendency of the stones,
which moves them outwardly on their axles, is not counteracted. Therefore, with
this form of mill, the centrifugal force which results from the rapid revolution of the
mill-stones, is materially aided by the outward tendency of the stones caused by
the friction on their working faces, and it tends to throw the stones outwardly on
their bearings and causes a great deal of wear. In my improved form of mill,
however, the supporting axles do not extend radially from the vertical operating
shaft but are supported therefrom by a suitable boxing in such relation that they will
be forwardly inclined to the radius and tangent of the circle of revolution, so that
the resistance of the working faces of the stones, (which is always in a direction
parallel to the said tangent), will give them an inward tendency on their axles and
counteract their outward tendency from the centrifugal force.
It is obvious that the position of the axles can be adjusted to such a nicety that
they will exactly counteract the centrifugal force at whatever the speed it is desired
to run the machine. Of course each adjusted position of the axles will only serve
to counteract the centrifugal force up to a certain rate of speed.
CLAIMS.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination of the vertical mill-stones, the axle or axles upon which said
mill-stones are journalled, and means for revolving said mill-stones around a common
centre; said axle or axles extending horizontally from the centre of rotation and
inclining forward with relation to the radius of revolution. substantially as set

page_text: 2. The combination of a vertical driving shaft, a cross beam secured to said
shaft having bearings on its opposite ends, and crank-axles supported in said
bearings at their inner journal ends and having outer journal ends upon which
vertical mill-stones are supported; said outer journal ends being inclined forward
with relation to the radius of revolution, substantially as set forth.
3. The combination of the vertical mill-stones, the axle or axles upon which said
mill-stones are journalled, means for revolving said mill-stones around a common
centre, and means for adjusting the angle of inclination of the axles to the radius
of the circle of rotation, substantially as set forth.
4. The combination of the central operating shaft, the cross-beam or boxing
keyed to said shaft, axles adjustably secured to said cross-beam, or boxing, and
vertical mill-stones mounted on said axles, whereby the angle of inclination of
the axles with relation to the radius of revolution can be adjusted, substantially as
set forth.
5. The combination of the vertical mill-stones, the crank-axles upon which the
stones are journalled, the vertical operating shaft, a cross-beam or boxing secured
to the shaft, and journal boxes in which the inner journal ends of the crank axles
are journalled, adjustably secured to the cross-beam or boxing, whereby the angle
of inclination of the axles can be adjusted with relation to the radius of revolution,
as set forth.
6. The combination of the vertical shaft, the cross-beam or boxing keyed to said
shaft and having curved faces or edges, journal boxes having curved faces fitting
against the curved faces of the cross-beam and adjustably secured thereto, and
crank-axles having inner and outer journal ends, the inner journal ends being
journalled in the adjustable boxes, and the outer journal ends supporting the mill-
stones, substantially as and for the purpose set forth.
7. The combination of the vertical shaft, the cross-beam or boxing keyed to said
shaft and having the opposite faces or edges curved and the ends horizontally
slotted, journal boxes fitting against the slotted ends of the cross-beam and having
curved flanges which fit against the curved portions of the cross-beam, screw-bolts
projecting from the curved faces of the cross-beam and engaging slots in the
curved flanges of the journal boxes, crank-axles journalled in the adjustable boxes,
and mill-stones mounted on the crank-axles, substantially as herein set forth.
A Serember
1000
VOIN I CRY UL DULCHICI LONG
HENRY MANTEY,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.