IMPROVEMENTS IN ROLLER MILLS
Year: 1883

page_text: LETTERS PATENT to Friedrich Carl Glaser of Berlin in the Kingdom of
Prussia and Empire of Germany Engineer and Patent-Solicitor, for an
Invention of IMPROVEMENTS IN ROLLER MILLS a communication to him
by Andreas Mechwart, Director of the Maschinenfabrik Actien Gesellschaft of
Budapest in the Kingdom of Hungary
PROVISIONAL SPECIFICATION left by the said Friedrich Carl Glaser at
the Office of the Commissioners of Patents on the 17th September 1883.
FRIEDRICH CARL GLASER of Berlin in the Kingdom of Prussia and Empire of
Germany, Engineer and Patent-Solicitor "IMPROVEMENTS IN ROLLER MILLS"
[A communication to him by Andreas Mechwart, Director of the Maschinenfabrik
Actien Gesellschaft of Budapest in the Kingdom of Hungary.]
In roller mills as they are usually constructed, when the hopper becomes empty
and is not at once replenished, the rollers revolve in close contact with one another
becoming heated and rapidly wearing out their surfaces and damaging the
flutings thereof. This invention relates to automatic apparatus so arranged
that when the supply of material to the rollers ceases, the rollers become separated
BO as not to rub against each other, and an alarum is sounded apprising the
attendants that the hopper requires to be replenished. The apparatus for. this
purpose may be arranged in various ways as will now be explained with reference
to the accompanying drawings. Fig. 1 is an end elevation of a roller mill with
the feed hopper and automatic apparatus shewn in section, and Fig. 2 is a side
elevation. a is a shaft with cranks a¹ connected by chains to the weights which
press the rollers together. On the shaft a is fixed a wheel b having ratchet teeth
over half its circumference, into which teeth takes a counterweighted pawl z. On
the prolongation of the shaft a, which is turned eccentric, is fixed a sleeve c, one
part of which next b is concentric with the eccentric part of the shaft a, whilst
the farther part of the sleeve is concentric with the body of the shaft a. On the
eccentric part of the sleeve c is fitted loose the pinion d for driving the feed
rollers, and on the outer part is fitted the driving pulley e, the pinion-d and

page_text: From the
pulley e being coupled so as to revolve together by means of a pin f entering a
slot g in an eccentric sheave h. On a fulcrum on the hopper is mounted a
lever from the inner end of which a flap 1 hangs within the hopper, or instead of
the flap a pyramidal or other suitably shaped piece might be employed, as shewn
in Fig. 3, so as to be pressed down by the material in the hopper.
lever k outside the hopper hangs a pawl catch m which takes into the teeth of the
wheel b, and beyond m hangs a fork i, the sides of which serve as guides, this fork
having a projecting tooth i¹. When the hopper is empty the flap is over-
balanced by the outer part of the lever k and its attachments.
For giving the
alarm there is a bell n struck by a hammer o, the tail p of which is moved by the
lever k-when it oscillates. For the purpose of throwing the apparatus out of use,
a weight 8 can be turned down to the position sbewn by the dotted lines in Fig. 1,
so as to overbalance and hold up the outer end of the lever k. The operation of
this mechanism is as follows:-While there is material in the hopper pressing
down the flap 1, the tooth is raised out of the reach of h, and the automatic
apparatus is inactive. But when the hopper is empty, so that there is little or no
weight on, then descends till it meets the periphery of the eccentric sheave h,
by the revolution of which the lever is caused to oscillate, causing the bell to
sound so as to give an alarm, and at the same time by means of the catch pawl m
turning round the wheel b and the shaft a on which b is fixed. The wheel b being
thus turned about half round, the cranks a¹ are brought to their highest position,
raising the weights suspended from them and thus relieving the mill rollers from
their pressure; also by this same movement, the eccentric pinion d is taken out of
gear with the wheel which drives the feed rollers and they thereupon cease to
revolve. This state of things continues, the alarm still sounding, until by
replenishing the hopper, the flap is again pressed down, whereupon the attendant
can by means of a handle x turn the shaft a half round to the position for the
working of the mill. Figs. 11, 12, 13 and 14 shew to an enlarged scale the position
of the parts when the mill is at work, Figs. 12ª, 13 and 14ª shew the positions
when the hopper is empty.
A modified construction of the automatic apparatus is shewn by the part section
Fig. 5 and the opposite end views Figs. 4 and 6, Figs. 40 5 and 6° shewing parts
of the apparatus separately. In this construction, a weight g fixed on the shaft a
slightly overbalances the weights suspended from the cranks a', and it is held in its
highest position by a catch t, which is released when the pressure on 7 ceases owing
to the emptying of the hopper. The weight g being thus released descends,
turning the shaft a about half.round and thus raising the pressing weights of the
mill rollers and stopping the feed rollers as above described. In this case the
hammer o is made to strike the bell p in the following manner :-A sheave d
which revolves with e on an eccentric part of the shaft a, has a stud f which
normally revolves clear of the tail p of the bell hammer, but when the shaft a is
turned half round by the descent of the weight g, the stud facts on the bell
hammer. When the hopper is replenished, the weight g is raised by the attendant
by means of a handle w. fixed on the shaft a, and the mill is again put in working
condition. Automatic apparatus according to the two constructions above
described may be applied to roller mills of forms other than that shewn in the
drawings.
Instead of employing a ratchet wheel or counterweight in the manner above
described, the automatic apparatus can be worked by a worm motion as shewn by
the side and end views Figa 7 and 9, and the part transverse and longitudinal
sections Figs. 8 and 10. Within the main hopper a is fixed a smaller hopper b, or
it might be a feed spout 6', furnished with a flap l, attached to a lever which is
fixed on a spindle d. At the outer end of d is a stud projecting at right angles
from it, on which stud is fitted free to revolve a worm wheel f. This wheel with a
weight & overbalances slightly the flap l.. With the worm wheel fengages a worm
on a spindle g having a pulley m driven by a band from one of the mill shafts w.
On the worm wheel is a crank pin z which is connected by a chaint to the pressure

page_text: lever y. The operation is as follows:-While there is sufficient pressure of material
on the flap to bear it down to the position ', the worm wheel fis raised out of gear
with the worm h; but when the supply of material ceases, so that the flap / can
freely rise, the wheel f descends into gear with h and is caused to revolve moving
the lever y to the position y whereby the mill rollers are separated. For giving
alarm, the bell n is struck by the hammer o acted on by a spring vand by studs
on the wheel f
Fig. 15 shews an arrangement for arresting the feed rollers when the mill rollers
are separated by hand by turning the spindle c by the handwheel d.. In this case,
a is the roller which has fixed bearings and bis the moveable roller. The axis of
the pulley which works the feed is on a lever from which a rod e extends down
to a joint of g that bears on the circumference of the hand wheel d. When this
wheel is turned so as to separate the mill rollers, the hollow d' is presented to the
joint of c which descends, lowering the pulley f and so slackening the band h that
the driving of the feed ceases. According to the modification shewn in Fig. 16,
a tightening roller k mounted on the lever f¹ is raised from the band h, leaving it
slack, by the counterweight f2 descending. And according to the modification
shewn in Fig. 17, the descent of e moves a fork lever f³ which throws the band
that drives the feed from the fast pulley n to a loose pulley n'. Fig. 18 shews
the gear for driving the feed rollers a¹ a² by toothed wheels bi b² and pinion c³, the
pinion c¹ being an intermediate for reversing the direction of rotation.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
"
the said Friedrich Carl Glaser in the Patent Office on the 13th March 1884.
FRIEDRICH CARL GLASER of Berlin in the Kingdom of Prussia and Empire of
Germany Engineer and Patent Solicitor "IMPROVEMENTS IN ROLLER MILLS'
a Communication to me from Andreas Mechwart, Director of the Maschinenfabrik
Actien Gesellschaft of Budapest in the Kingdom of Hungary
In roller mills as they are usually constructed, when the hopper becomes empty
and is not at once replenished, the rollers revolve in close contact with one another
becoming heated and rapidly wearing out their surfaces and damaging the flutings
thereof. This invention relates to automatic apparatus so arranged that when the
supply of material to the rollers ceases, the rollers become separated so as not to
rub against each other, and an alarum is sounded apprising the attendants that the
hopper requires to be replenished. The apparatus for this purpose may be arranged
in various ways as will now be explained with reference to the accompanying
drawings. Fig. 1 is an end elevation of a roller mill with the feed hopper and
automatic apparatus shewn in section, and Fig. 2 is a side elevation. a is a shaft
with cranks a' connected by chains to the weights which press the rollers together.
On the shaft a is fixed a wheel b having ratchet teeth over half its circumference,
into which teeth takes a counterweighted pawl z. On the prolongation of the
shaft a, which is turned eccentric, is fixed a sleeve c, one part of which next b is
concentric with the eccentric part of the shaft a, whilst the farther part of the
sleeve is concentric with the body of the shaft a. On the eccentric part of the
sleeve c is fitted loose the pinion d for driving the feed rollers, and on the outer
part is fitted the driving pulley e, the pinion d and pulley e being coupled so as to
revolve together by means of a pin f entering a slot g in an eccentric sheave h. On
a fulcrum on the hopper is mounted a lever k from the inner end of which a
flap hangs within the hopper, or instead of the flap a pyramidal or other
suitably shaped piece might be employed, as shewn in Fig. 3, so as to be pressed
down by the material in the hopper. From the lever k outside the hopper hangs a
pawl catch m which takes into the teeth of the wheel b, and beyond m hangs a
fork i, the sides of which serve as guides, this fork having a projecting tooth ¹.
When the hopper is empty the Hap is overbalanced by the outer part of the
lever and its attachments. For giving the alarm there is a bell n struck by a
hammer o, the tail p of which is moved by the lever when it oscillates. For the
purpose of throwing the apparatus out of use, a weight 8 can be turned down to
the position shewn by the dotted lines in Fig. 1, so as to overbalance and hold up
the outer end of the lever k. The operation of this mechanism is as follows:-
While there is material in the hopper pressing down the flap l, the tooth is raised
out of the reach of h, and the automatic apparatus is inactive. But when the
hopper is empty, so that there is little or no weight on l, then i descends till it
meets the periphery of the eccentric sheave h, by the revolution of which the
lever k is caused to oscillate, causing the bell to sound so as to give an alarm, and
at the same time by means of the catch pawl m turning round the wheel b and the
shaft a on which bis fixed. The wheel b being thus turned about half round, the
cranks a¹ are brought to their highest position, raising the weights suspended from
them and thus relieving the mill rollers from their pressure; also by this same
movement, the eccentric pinion d is taken out of gear with the wheel which drives
the feed rollers, and they thereupon cease to revolve. This state of things
continues, the alarm still sounding, until, by replenishing the hopper, the flap is
again pressed down, whereupon the attendant can, by means of a handle t, turn the
shaft a half round to the position for the working of the mill. Figs. 11, 12, 13

page_text: and 14 shew to an enlarged scale the position of the parts when the mill is at work,
Figs. 11 12 and 13ª shew the positions when the hopper is empty.
A modified construction of the automatic apparatus is shewn by the part section
Fig. 5 and the opposite end views Figs. 4 and 6, Figs 4* 5 and 6 shewing parts of
the apparatus separately. In this construction, a weight g fixed on the shaft a
slightly overbalances the weights suspended from the cranks a¹ and it is held in its
highest position by a catch t, which is released when the pressure on ceases owing
to the emptying of the hopper. The weight g being thus released descends, turning
the shaft a about half round and thus raising the pressing weights of the mill
rollers and stopping the feed rollers as above described. In this case, the hammer o
is made to strike the bell n in the following manner: A sheave & which revolves
with e on an eccentric part of the shaft a, has a stud f which normally revolves
clear of the tail p of the bell hammer, but when the shaft a is turned half round
by the descent of the weight g, the stud facts on the bell hammer. When the
hopper is replenished, the weight g is raised by the attendant by means of a
handle w fixed on the shaft a, and the mill is again put in working condition.
Automatic apparatus according to the two constructions above described may be
applied to rollers mills of forms other than that shewn in the drawings.
Instead of employing a ratchet wheel or counterweight in the manner above
described, the automatic apparatus can be worked by a worm motion as shewn by
the side and end views Figs 7 and 9, and the part transverse and longitudinal
sections Figs 8 and 10. Within the main hopper a is fixed a smaller hopper b, or
it might be a feed spout b¹ furnished with a flap 7, attached to a lever k which is
fixed on a spindle d. At the outer end of d is a stud at right angles from it, on
which stud is fitted free to revolve a worm wheel f. This wheel with a weight s
overbalances slightly the flap . With the worm wheel f engages a worm h on a
spindle g having a pulley m driven by a band from one of the mill shafts w. On
the worm wheel is a crank pin z which is connected by a chain t to the pressure
lever y. The operation is as follows:-While there is sufficient prussure of material
on the flap to bear it down to the position ", the worm wheel ƒ is raised out of
gear with the worm h; but when the supply of material ceases, so that the flap
can freely rise, the wheel f descends into gear with h and is caused to revolve
moving the lever y to the position y¹ whereby the mill rollers are separated. For
giving alarm, the bell n is struck by the hammer o acted on by a spring v and by
studs on the wheel f.
Figs. 15 and 15. shew an arrangement for arresting the feed rollers when the
mill rollers are separated by hand by turning the spindle c by the handwheel d.
In this case a is the roller which has fixed bearings and b is the moveable roller.
The axis of the pulley f, which works the feed is on a lever from which a rod e
extends down to a joint of g that bears on the circumference of the hand wheel d.
When this wheel is turned so as to separate the mill rollers, the hollow d¹ is
presented to the joint of e which descends, lowering the pulley f and so slackening
the band h that the driving of the feed ceases. According to the modification
shewn in Fig. 16, a tightening roller k mounted on the lever f¹ is raised from the
band h, leaving it slack, by the counterweight f' descending. And according to
the modification shewn in Figs 17 and 17, the descent of e moves a fork lever f³
which throws the band that drives the feed from the fast pulley n to a loose
pulley n. Figs 18 and 18 shew the gear for driving the feed rollers a¹ a³ by
toothed wheels b' b and pinion c², the pinion c¹ being an intermediate one for
reversing the direction of rotation. The pinion c* is mounted on an eccentric part
of the cranked shaft e¹ so that by turning this by means of the lever g¹ the pinion
is moved out of gear with the wheels b¹ b³.
Having thus described the nature of the said invention and in what manner the
same is to be performed, as communicated to me by my correspondent, I claim in
respect of roller mills of the kind herein referred to:
First. Effecting the automatic throwing out of gear of the grinding and feed
rollers by means of a flap or prism l operating in combination with a leverk ratchet

page_text: wheel b and eccentric h, substantially as herein described with reference to the
accompanying drawings.
Second. Effecting the automatic throwing out of gear of the grinding and feed
rollers by means of a flap or prism operating in combination with the balance
weight g, substantially as herein described.
Third. Effecting the automatic throwing out of gear of the grinding and feed
rollers by means of a small feed passage 61 contained within the main feed channel
and operating in combination with the flap l, worm h and worm wheel f, substan-
tially as herein described.
Fourth. In combination with the automatic apparatus referred to in the
preceding claims, the use of an alarm bell n and hammer o, operating as herein
set forth.
Fifth. Effecting the simultaneous putting in and out of action of the grinding
and feed rollers by means of the hand wheel d having cam shaped or recessed
surface and operating in combination with the shaft c, connecting rod e and
swinging bearing of the driving pulley f, substantially as herein described with
reference to Figs. 15 and 15 of the drawings.
Sixth. The modified arrangement of the mechanism referred to in the preceding
claim described with reference to Fig. 16 whereby the cam shaped hand wheel d is
made to act upon the driving belt by means of the tightening pulley k and lever f¹
with balance weight f³.
Seventh. The modified arrangement of the mechanism referred to in the fifth
claim described with reference to Figs 17 and 17 whereby the cam shaped hand
wheel d is made to act upon the driving belt by means of the fork f³. so as to move
it on to either the fast pulley n or the loose pulley n¹.
Eighth. Effecting the throwing out of gear of the toothed wheel c³ by means of
the eccentric part of the cranked shaft e operated by the lever g¹ in combination
with chains and weights, substantially as described with reference to Figs 18
and 18" of the drawings.
In Witness whereof I the said Friedrich Carl Glaser have hereunto set my hand
and seal this tenth day of March in the year of our Lord One thousand eight
hundred and eighty-four.
FRIEDRICH CARL GLASER,
(L.B.)