Year: 1888

page_text: Date of Application, 24th Jan., 1888
Complete Specification Left, 21st Sept., 1888
Complete Specification Accepted, 16th Nov., 1888
1, PHILIPP TAFEL, of Augsburg, in the Empire of Germany to morowy
nature of this invention to be as follows:-
In order to attain the differential velocity of the circumferences of grinding rollers the
driving has heretofore been effected from one roller with spur wheels connecting the
other roller, thereto, but a comparatively small differential velocity can be attained in
this manner.
In order to increase this velocity, it has been proposed to increase the diameter
of one of the rollers but the drawing in angle of the grinding rollers thereby becomes
unfavorable, and despite this a certain differential velocity of the roller circumferences
is not exceeded.
With the driving gear described in the present specification however, the differential
velocity can be increased at will without necessitating the employment of rollers of
unequal diameter consequently the most favorable drawing-in angle can be selected
for the produce to be ground, moreover, the circumferential velocities of the grinding
surfaces are very different. This difference is obtained by the employment of a
peculiar rope gear which, employed as a yielding driving device prevents the stoppage
or dead-lock of the motion of the rollers.
The exact arrangement of the driving mechanism is as follows:-
The roller which I will hereinafter term the driving roller is driven by means of
a belt pulley secured to the same shaft, upon the other end of the said shaft is
arranged a pair of rope pulleys the inner one or guide pulley is loose upon a sleeve
whilst the outer one is fixed upon the shaft of the roller.
The rope is driven from the latter, passes over tension pulleys and over the
guide pulley on its way to a pulley on the shaft of the worm, to effect the driving
of this shaft.
The inner and outer pairs of pulleys together with the tension pulleys are
stepped so that by shifting the rope, different velocities of the pulleys inay be
obtained.
The tension pulleys are supported in such a manner that they can by means of a
spring or weights, be kept under tension or displaced.

page_text: By means of this driving device the greatest diversity can be attained in the
circumferential velocity of the rollers, without the drawing-in angle becoming
unfavorable.
Whilst in the above described construction the transmission of motion is performed
by means of a rope, with a worm and worm wheel included, the said worm and worm
wheel may if desired be entirely dispensed with, and the transmission of motion
effected by means of ropes wedged into their grooves.
In a single-paired groats mill, the driving roller is set in rotation by the pulley
fixed upon one of the journals of the said roller. Upon the opposite journal of the
said roller is placed a rope pulley.
A second rope pulley is arranged upon the journal of the second roller but as both
rope pulleys have a larger diameter than their respective rollers, they cannot be placed
in the same vertical plane, therefore the second rope pulley is arranged in front of the
pulley upon the journal of the driving roller.
The driving rope passes from the latter to the guide pulley placed below, from this
to the second pulley, and from here to the guide pulley, and then back to the pulley on
the driving journal.
As both pulleys are not in the same vertical plane, the guide pulleys in order that
the rope shall be properly conducted again and again on to small roller of the rope
pulley, must be placed obliquely.
As the two guide pulleys are at the same time tension pulleys, they may be arranged
in any suitable manner for adjustment.
Thus for example these two pulleys may be placed upon a lever which is common to
both and is pivotted upon, its journal.
At the opposite end of the said lever is provided a toothed segment with which
engages the thread of the worm; which worm is firmly held in a support.
By the turning of the worm the lever is moved upwards or downwards upon its
journal whereby the driving ropes are stretched more or less.
The difference in the velocity of the two rollers working together is obtained by
stepped pulleys.
The rope passes from the driving pulley to a tension pulley, and then over
the driven pulley, passing from thence to another tension pulley and back to the
driving pulley consequently a greater differential velocity occurs than in the
former case.
The tension pulleys must of course be arranged accordingly, that is to say, have just
as many grooves as each driving pulley.
This arrangement is of extreme importance especially for small mills which perform
all the operations between one and the same pair of rollers, and yet with various
differential velocities.
In another form or modification, in which four rollers are used, I arrange upon
the shaft of the driving roller the driving pulley, and upon this shaft is also
arranged the rope pulley which carries a rope passing over the guide pulley and.
driving the rope pulley and thereby the roller placed upon the same shaft and revolving
in the same direction as the driving roller.
The rope passes further over a lower guide pulley back to the driving pulley.
Exactly in the same manner the two other rollers also revolving in the same direction,
are driven on the other side of the apparatus by means of a belt pulley and rope
pulleys.

page_text: I, PHILIPP TAFEL, of Augsburg, in the Empire of Germany, 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:-
In order to attain the differential velocity of the circumferences of grinding
rollers the driving of the same has heretofore been effected from one roller, with spur
wheels connecting the other roller thereto but only a comparatively small differential
velocity can be attained in this manner.
In order to increase this velocity, it has been proposed to increase the diameter of
one of the rollers but the "drawing-in" angle or angles formed between the grinding
rollers thereby becomes unfavorable, and despite this a certain differential velocity of
the roller circumferences is not exceeded.
With the driving gear described in the present specification however the differential
velocity can be increased at will without necessitating the employment of rollers of
unequal diameter consequently the drawing-in angle can be selected which is best
suited to the produce to be ground, moreover, the circumferential velocities of the
grinding surfaces are very different. This difference is obtained by the employment
of a peculiar rope gear which, is employed as a yielding driving device prevents the
stoppage or dead-lock of the motion of the rollers.
The invention is illustrated in the accompanying drawings the figures of which are
hereinafter referred to.
The arrangement of the driving mechanism is as follows:
Referring to Figures 1 and 1ª the driving roller W is driven by means of a belt
pulley a secured to the same shaft, at the other end of the said roller is arranged a
pair of rope pulleys d and e; the inner one or guide pulley e is loose upon a sleeve q
whilst the outer one d is fixed upon the shaft of the roller.
The rope is driven from the latter, passes over tension pulleys s¹ and over the guide
pulley e on its way to a pulleys on the shaft p of the worm o Figure 1b to effect the
driving of this shaft.
The inner and outer pairs of pulleys d and e together with the tension pulleys, are
stepped, so that by shifting the rope, different velocities of the pulleys may be
obtained.
The tension pulleys are supported in such a manner that they can by means of
a spring or weights be kept under tension or displaced.
By means of this driving device the greatest diversity can be attained in the
circumferential velocity of the rollers, without the "drawing-in" angle becoming
unfavorable.

page_text: Whilst in the above described construction the transmission of motion is performed
by means of a rope, with a worm and worm wheel included, the said worm and worm
wheel may, if desired be entirely dispensed with, and the transmission of motion
effected by means of ropes wedged into their grooves, as shown in Figures 2 to 4, in
which
Figures 2, 2ª and show the arrangement of a groats mill having one pair of
rollers.
Figures 3, 3 and 3b show a similar arrangement for a mill with a double pair of
rollers having one driving device and
Figures 4, 4 and 4° show an arrangement of a mill with a double pair of rollers
and two driving devices.
In the single-paired mill shown in Figures 2, 2ª and 2b the driving roller W is set
in rotation by the pulley a fixed upon one of the journals of the said roller. Upon
the opposite journal of the said roller W is placed a rope pulley d.
A second rope pulley e is arranged upon the journal of the second roller W₁ but as
both rope pulleys have a larger diameter than their respective rollers, they cannot be
placed in the same vertical plane, therefore the rope pulley e is arranged in front of
the pulley d.
The driving rope passes from the pulley d to the guide pulley s¹ placed below,
then from this to the second pulley e and from here to the guide pulleys and then
back to the pulley d. on the driving journal.
As both pulleys are not in the same vertical plane, the guide pulleys s and s¹ must
be placed obliquely as shown in Figure 2b in order that the rope shall be properly
conducted again and again on to the rope pulleys.
As the two guide pulleys s and serve at the same time as tension pulleys,
they may be arranged in any suitable manner for adjustment.
Thus for example as shown in Figures 2 and 2b these two pulleys may be
placed upon a lever f which is common to both and is pivoted upon a journal Z.
At the opposite end of the said lever f is provided a toothed segment with
which engages the thread of the worm g which is firmly held in a support h.
By turning the worm g in one or the other direction the lever f is moved upwards
or downwards whereby the driving ropes are stretched more or less.
The difference in the velocity of the two rollers working together is obtained by
stepped pulleys.
The rope passes over the rope groove m¹ of the driving pulley and then over the
driven pulley consequently a greater differential velocity occurs than in the former
case.
The tension pulleys s and s¹ must of course be arranged accordingly, that is to
say, have just as many grooves as each driving pulley.
This arrangement is of extreme importance especially for small mills which
porform all the operations between one and the same pair of rollers because it
enables the operation with the same pair of rollers and yet with various differential
velocities.
In the form or modification shown in Figures 4, 4" and 4 in which four rollers are
used I arranged upon the shaft of the driving roller W₁ the driving pulley a and
upon this shaft is also arranged the rope pulley d which carries a rope passing
over the guide pulleys and driving the rope pulley e consequently the roller
placed upon the same shaft and revolving in the same direction as the driving
roller WI.
The rope further passes over the guide pulley s back to the driving pulley d.
The two other rollers V₁ W also revolving in the same direction, are driven in the
same manner on the other side of the apparatus by means of a belt pulley a' and
rope pulleys d' and e'.
'
The taking up of the slack of the rope effected in the same manner as before
described, that is to say, by a lever journalled at and worm h carried in
supports g.

page_text: 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:-
In roller mills the employment of rope driving gear working in grooved pulleys
and effecting a differential velocity of the grinding rollers the said ropes being made
of hemp, flax, wire, cotton, india-rubber or any other suitable material, and a
mechanism being provided for taking up the slack, all substantially in the manner
and for the purpose described with reference to the accompanying drawing.
21
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.