Improvements in Grinding Mills.
Year: 1896

page_text: Date of Application, 14th Nov., 1896-Accepted, 13th Mar., 1897
COMPLETE SPECIFICATION.
Improvements in Grinding Mills.
I, DAVID LEROY SPRAGUE, of Clear Lake, County of Cerro Gordo, State of Iowa,
U.S.A., Jeweller, 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:-
The grinding mill of this invention is illustrated in the accompanying drawing,
Fig. 1 being a perspective view and Fig. 2 a vertical section of the same through
the main shaft.
A is the base or frame of any suitable material and rising therefrom are the
uprights or standards A supporting the hopper B which may be provided with a
suitable slide B¹ to regulate the discharge therefrom into the passage C extending
from the bottom of the hopper and communicating with a horizontal hollow shaft D
Within the hollow
at one end thereof, the other end carrying a grinding bur E.
shaft is a feed worm F extending to the lower end of the passage C, the other end
of said worm being screwed into a shaft G on which is secured another grinding
bur F. On each of these shafts is a pulley I around each of which passes a belt Ii
which pass over pulleys I on the line shaft I arranged overhead, and one of said belts
being crossed, as shewn in Fig. 1, so that the burs will be turned in opposite
directions, thus giving the mill a double action, as will be readily understood. The
boxes J in which these shafts run, are attached to metal frames K, K¹, K³, K³,
through the ends of which run the adjusting rods L one on each side of said frames
and on the end of each adjusting rod is a spiral spring M and a sprocket wheel O
serving as a nut connected by an endless belt or chain P, thereby enabling the
operator to readily and easily adjust the burs to any desired tension for fine or coarse
grinding. The burs are covered by a case Q constructed in two parts overlapping
each other and each part fastened to one of the frames K' or K2, on the outside of
each bur, as clearly shewn in the drawing. A discharge spout R is provided beneath
the burs and through which the ground material is conducted to the sack or any
other suitable receptacle provided therefor.
As will be readily understood, the metallic frames K, K1, K2, K', are movably
mounted upon the rods by which they are supported, so that by ádjustment of the
nuts O the one part of the casing Q is made movable within the other. The metal
frame K operates in connection with the bearing lug on the frame A as a stop to
limit the yield of the burs.
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 combination with the fixed rods, threaded at their outer extremities, of the
fixed and movable overlapping halves of the casing, the adjustable frames K, K', K, K³,
the coiled springs and the adjustable nuts O geared together, all substantially as
described and shewn and for the purpose specified.
2. The combination with the frames K, K' of the burs, the case surrounding said
burs and formed in overlapping sections, one of which is fixed and the other movable
to and from the same, the removable frames K, K', K', K³, bearings for the shaft
and means for adjusting said frames to regulate the distance between the burs,
substantially as described and shewn.

page_text: 3. The combination with the frames K1, K2 of the burs, the case surrounding said
burs and formed in overlapping sections, one of which is fixed and the other movable
to and from the same, the removable frames K, K', K2, K³, bearings for the shaft
and means for adjusting said frames to regulate the distance between the burs, said
frames having a portion serving as a stop to limit the yield of the burs, substantially
as described and shewn.
Dated this 14th day of November 1896
THOMAS R. SHILLITO,
89 Chancery Lane, London, W.C., Agent for the Applicant