Improvements in Levigating or Grinding Machinery.
Year: 1894

page_text: Date of Application, 5th July, 1894
Complete Specification Left, 5th Apr., 1895-Accepted, 11th May, 1895
PROVISIONAL SPECIFICATION.
Improvements in Levigating or Grinding Machinery.
I, ARTHUR MAW of Benthall Works, Jackfield in the County of Salop,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in machinery for levigating or grinding
in a wet state flints, Cornish-stone, glazes, enamels, and such other materials of a
like nature as are usually ground or pulverized in that manner.
In the ordinary form of levigating pan, the effect of the wear between the faces
of the mullers and the bedstone, has a tendency to hollow out the bedstone into the
form of a basin while the face of the muller assumes a convex form corresponding
with it thereby necessitating the frequent dressing or channelling of the mullers so
that the material can be admitted under them.
In consequence of the peculiar shape occasioned by the wear of the ordinary
bedstones and the mullers it is a matter of difficulty and expense to fit new mullers
to existing bedstones, inasmuch as the latter require to be dressed flat on the
occasion of each renewal.
My invention has for its object to increase the efficiency of the action of the
muller and the bedstone, and my invention effects the saving of the labor required
for the grooving and dressing of the mullers through the peculiar operation of the
wear on the faces of the mullers and bedstone by which the wear of mullers and
bedstone is spread as nearly as may be evenly over the whole of their respective
faces but in such a manner that they are never at any part of their respective
revolutions absolutely applied to one another over the whole of their respective faces
at the same time, but although the whole faces both of mullers and bedstone come
into operation at each revolution they do so in such a manner as to admit the
material under the faces of the mullers, without the labor and loss of grinding
surface involved by the usual grooving or channelling of the mullers.
In carrying out my invention I employ two or more mullers or sets of mullers
working on the same bed. These mullers are preferably driven in opposite
directions by two or more vertical shafts which may be rotated on their axis in any
convenient manner. I also make the bedstone upon which the mullers work
revolve in a manner similar to the bed of edge runners.
The vertical shaft carrying each of the mullers may be driven by bevel gearing
from a horizontal shaft above. The rotation of the bedstone may also be effected
from off the same horizontal driving shaft. For this purpose the bedstone is fixed
on a table having at its outer edge a toothed wheel gearing with a pinion on a
vertical shaft which receives rotation by bevel gearing from the horizontal shaft ; or
by bevel gearing from beneath.
In machines of large size instead of employing two mullers each revolved by a
vertical shaft can employ several mullers propelled by two or more arms attached
to each vertical shaft.
Dated this 5th day of Jul. 1804
J. C. MEWBURN & ELLIS,
55 & 56, Chancery Lane, London, Patent Agents.

page_text: improvements in Levigating or Grinding Machinery.
I, ARTHUR MAW of Benthall Works, Jackfield in the County of Salop,
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:-
This invention relates to improvements in machinery for levigating or grinding
in a wet state glazes, enamels, and such other materials of a like nature as are
usually ground or pulverized in that manner.
In the ordinary form of levigating pan, the effect of the wear between the faces
of the mullers and the bedstone has a' tendency to hollow out the bedstone into the
form of a basin while the face of the muller assumes a convex form corresponding
with it, thereby necessitating the frequent dressing and channelling of the mullers
so that the material can be admitted under them.
In consequence of the peculiar shape occasioned by the wear of the ordinary
bedstones and the mullers it is a matter of difficulty and expense to fit new mullers
to existing bedstones, inasmuch as the latter require to be dressed flat on the
occasion of each renewal.
My invention has for its object to increase the efficiency of the action of the
muller, and the bedstone, and my invention effects the saving of the labor required
for the grooving and dressing of the mullers through the peculiar operation of the
wear on the faces of the mullers and bedstone by which the wear of the mullers
and bedstone is spread as nearly as may be evenly over the whole of their respective
faces but in such a manner that they are never at any part of their respective
revolutions absolutely applied to one another over the whole of their respective faces
at the same time, but although the whole faces both of mullers and bedstone come
into operation at each revolution they do so in such a manner as to admit the
material under the faces of the mullers, without the labor and loss of grinding
surface involved by the usual grooving or channelling of the mullers.
In carrying out my invention I employ two or more mullers or sets of mullers
working on the same bed. These mullers are driven preferably in opposite
directions by two or more vertical shafts which may be rotated on their axes in any
convenient manner. I also make the bedstone upon which the mullers work
revolve in a manner similar to the bed of edge runners.
Each of the vertical shafts carrying the muilers may be driven by bevel gearing
from a horizontal shaft above. The rotation of the bedstone may also be effected
from off the same horizontal driving shaft.
For this purpose the bedstone is fixed on a table having at its outer edge a
toothed wheel gearing with a pinion on a vertical shaft which receives rotation by
bevel gearing from the horizontal shaft or the vertical shaft may be driven by
bevel gearing from beneath.
The accompanying drawings represent a machine constructed according to my
invention. Figure 1 is a side elevation partly in section, and Figure 2 a plan on
the line 2-2 of Figure 1.
A is the bedstone resting on an iron bed plate supported by a vertical spindle B.
On the outer edge of the bed plate is a toothed wheel C gearing with and driven
by a pinion D on a vertical shaft E which derives its motion from the driving
shaft F through the intermediation of the bevel pinions G G. H is the tub for
containing the material to be ground or levigated; it is carried by and revolves
with the bed plate. II are two mullers working on the bedstone A. They are
carried by vertical shafts K K driven in opposite directions from the shaft F

page_text: through the intermediation of the bevel pinions LL; the two mullers just clear
one another in their revolutions.
The movement of the various parts causes the grinding surfaces to describe
epicycloidal or scroll curves which never return exactly upon themselves; con-
sequently the bed remains approximately level but the very slight irregularity of
surface produced by wear both in the bedstone and mullers operates in such a
manner as to leave at every period of their revolutions a sufficient interstice for the
admission of the material that is being ground without the loss of grinding surface
involved by grooving and channelling; and inasmuch as at every revolution the
part of the mullers which at one time provides the openings, at the next receives
the greatest pressure and vice versa, there is a constant crushing as well as grinding
action and it has been found in practice that the smoother the grinding faces are
worn the more efficient is the operation of the machine.
In machines of large size instead of employing two mullers each revolved by a
vertical shaft I can employ several mullers carried by two, or more arms attached
to each vertical shaft.
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 :-
1. In a levigating or grinding machine, the combination of a revolving bedstone
and two or more mullers made to revolve above the bedstone on vertical axes
substantially as hereinbefore described.
2. Constructing levigating or grinding machinery substantially as bereinbefore
described and represented in the accompanying drawings.
Dated this 5th day of April 1805
J. C. MEWBURN & ELLIS,
55 & 56, Chancery Lane, London, Chartered Patent Agents.