AN IMPROVED ARRANGEMENT OF DRIVING BANDS FOR ROLLER MILLS
Year: 1885

page_text: I ANDREAS MECHWART of Buda Pesth in the Kingdom of Hungary, Austro-
Hungarian Empire, Engineer do hereby declare the nature of my invention for
"AN IMPROVED ARRANGEMENT OF DRIVING BANDS FOR ROLLER MILLS," to be as
follows:-
This invention relates to a novel arrangement of driving bands suitable for
three-roller mills, whereby irregularity of pressure on the rollers is prevented and
the production of a uniform quality of meal through the whole breadth of the
machine is ensured,
In three roller mills, as is well known, the middle or fixed roller, is the driven
roller from which the other rollers derive their motion.
I now propose to fit the axles of these rollers, at their opposite ends with band
pulleys and to provide on each side of the machine a tension pulley which will be
carried by a lever capable of adjustment by a worm and sector rack or equivalent
means in any desired position.
From each pulley on the axle of the top roller I lead down a band to the tension
pulley carried by the rock-lever and from this tension pulley I lead the band over
a pulley on the axle of the middle or fixed roller.
From this pulley the band descends and laps round the pulley on the axle of the
bottom roller and from this pulley the band passes up to the pulley on the top
roller.
A like arrangement is followed on both sides of the mill.
The relative diameters of the pulleys ou the several roller axles will be such as
to ensure the required surface speeds for the rollers while the proper direction for
the rotation of the rollers is ensured by the symmetrical disposition of the bands
above described.

page_text: An Improved Arrangement of Driving Bands for Roller Mills.
I ANDREAS MECHWART of Buda Pesth in the Kingdom of Hungary, Austro-
Hungarian Empire, Engineer, 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 a novel arrangement of driving bands suitable for
three-roller mills, whereby uniformity of pressure on the rollers may be ensured,
and consequently the production of a uniform quality of meal, through the whole
breadth of the machine, obtained.
In three roller mills, as is well known, the middle or fixed roller is the driven
.roller, from which the other rollers derive their motion.
I now propose to fit the axles of these rollers, at their opposite ends, with pulleys
for receiving endless driving bands, and to provide, on each side of the machine, a
tension pulley for tightening up such bands.
The mode of carrying out my invention is shewn in the accompanying drawing,
where
Fig. 1 is a side elevation of so much of a three-roller mill as will serve to explain
the adaptation of my invention thereto, and
Fig. 2 is a plan of the same.
In these Figures, A is the middle or driven roller, mounted, as usual, in fixed
bearings; B is the top roller, and C the bottom roller.
The axles of each of these rollers are fitted at their opposite ends with band
pulleys a bc, of suitable diameters, as will be hereafter explained.
DD are tension pulleys for regulating the bite of the driving bands E E upon
the pulleys a. b, c.
These pulleys are shewn as carried by levers d d, fulcrumed at d¹, and furnished
with sector racks d², for the purpose of adjusting their position. The driving
bands E, it will be seen, are led down from the pulleys on the axle of the top
roller, to their respective tension pulleys D, and from these tension pulleys, they
are led over and around the pulleys a of the roller A, from which they descend,
and lap around the pulley c of the lower roller C, and from these pulleys the bands
pass up to their respective pulleys 6 of the top roller B.
The relative diameters of the pulleys a b c will be such as to ensure the required
surface speeds for the rollers, while the proper direction for the rotation of the
rollers is ensured by the symmetrical disposition above described of the bands E.
For tightening these bands, and putting the requisite pressure on the rollers B C,
various mechanical devices may be employed.-In the drawing I have shewn a
worm d³ gearing into the segment rack , the turning of which worm in its fixed
bearings (carried by the framing) will rock the lever d, thereby lowering the
pulley D, and putting the requisite tension upon its band.
In place, however, of the worin, a spur pinion may be used to act upon the sector
rack, a retaining pawle or its equivalent serving to maintain the position of the
pinion, or set screws may be employed to adjust the bearing of the tension pulley
in its guide or support.

page_text: 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
In a three-roller mill, the arrangement of driving bands and pulleys as described,
whereby I am enabled to ensure uniformity of pressure on the top and bottom
rollers, with the result hereinbefore set forth,