Year: 1885

page_text: We, AUGUST CHRISTIAN NAGEL, REINHOLD HERMANN KAEMP and ADOLF
WILHELM FRANZ GEORG LINNENBRÜGGE, of Hamburg, German Empire, Engine-
manufacturers, do hereby declare the nature of this invention to be as follows:-
Our invention relates to roller-mills and other machines having two parallel
shafts provided each with a pulley for operating the same by means of a strap or
other flexible power-conveying medium, and the improvements consist in arranging
the said pulleys, which we shall call the roll-pulleys, in different planes close to
each other, and in combining therewith an oblique tension and guiding-pulley
adapted to lead the strap from one of the said roll-pulleys to the other. Moreover
it consists in means for adjusting the position of the tension and guiding-pulley
in respect to the roll-pulleys, and in combining with the latter and the tension and
guiding-pulley a conical driving-pulley.
If in a roller-mill both rolls are to be operated by means of a driving-pulley, a
strap, and two pulleys keyed on the roll-shafts, (or roll-pulleys) and if, as is usual,
the latter two pulleys are larger in diameter than the rolls, they cannot be placed
in a line. Now according to our invention the said roll-pulleys are keyed on the
like ends of the roll shafts so as to be clear of each other, and a guiding-pulley is
so arranged in respect to them in an oblique position that it may conduct the strap
from one roll-pulley to the other. The strap coming from the driving-pulley is
then passed around one of the roll-pulleys, thereupon over the guiding-pulley,
subsequently from the guiding-pulley to the second roll-pulley and thence back to
the driving-pulley.
The guiding-pulley rotates on an axle mounted on an arm or carrier, and which,
on account of the described position of the pulley is arranged at an angle to the
roll-shafts. The said axle is or may be provided with means for adjusting it to
the required angular position.
The said arm or carrier is so constructed that it may be rotated about an axis
parallel to the shafts ƒ and g, or coinciding with one of them. For this purpose it
may be mounted with an annular part on a ring or circular body permanently
fixed to the frame of the machine and fitted with suitable contrivances for securing
the carrier thereto in any desired position. The guiding-pulley is thus also made
servicable as tension-pulley.

page_text: Considering that the driving-pulley has to cooperate with the two roll-pulleys,
the two strap-parts passing from the former to the latter, do not run with their
centerlines (or their edges) in a plane parallel to the planes of the pulleys. If the
driving-pulley is at a considerable distance from the roll-pulleys this deviation
of the strap-parts may be counterbalanced, and the danger of the strap slipping off
the pulleys avoided, by making the driving-pulley sufficiently convex, and by
placing it with its contral plane opposite to the middle of the space between the
roll-pulleys. But if the distance between the driving-pulley and the roll-pulleys
is small, it is preferable to make the driving-pulley conical, and to mount it on
the driving-shaft so that it will be opposite to the roll-pulley which is to receive
the strap from the driving-pulley, and that its largest diameter will be in a plane
with the edge of the said roll-pulley that is turned away from the other roll-pulley.
Instead of a strap any other flexible and suitable power-transmitting medium,
such as a rope or a plurality of parallel ropes may be employed, provided only that
the rims of the pulleys be formed in corresponding manner.

page_text: We AUGUST CHRISTIAN NAGEL, REINHOLD HERMANN KAEMP, and ADOLF
WILHELM FRANZ GEORG LINNENBRÜGGE, of Hamburg German Empire, Engine-
manufacturers, 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 :-
Our invention relates to roller-mills and other machines having two parallel
shafts provided each with a pulley for operating the same by means of a strap or
other flexible power-conveying medium, and the improvements consist in arranging
the said pulleys, which we shall call the roll-pulleys, in different planes close to
each other, and in combining therewith an oblique tension and guiding-pulley
adapted to lead the strap from one of the said roll-pulleys to the other. Moreover
they consist in means for adjusting the position of the tension and guiding-pulley
in respect to the roll-pulleys and in combining with the latter and the tension and
guiding-pulley a conical driving-pulley.
On the annexed sheet of drawings our improved driving-gear is represented in
combination with the rolls of a roller-mill, by Fig. 1 in front elevation, by Fig. 2
in a sectional side-view, and by Fig. 3 in sectional plan. In the latter Figure a
portion of a second pair of rolls is shown. Fig. 4 is a guiding-pulley with section
of a modified.arrangement of the adjusting-device. Fig. 5 represents a portion of
the gear with conical driving-pulley. Fig. 6 is a view of the said conical pulley.
Fig. 7 shows the improved gear in different positions relatively to the driving-
pulley.
For the purpose of operating roller-mills solely by means of straps, various
systems of driving-gear in which tension and guiding-pulleys are employed, have
been contrived; but all these systems present certain inconveniencies. In many
of them the shaft carrying the driving-pulley requires to be placed in a particular
definite position in respect to the mill, usually vertically below the same, so that
these systems are not adapted for the transmission of power to the mill from a
shaft having a materially different position. In other cases two straps are
employed, one for transmitting motion from the main driving-pulley to a counter-
shaft, or to one of the two roll-pulleys, and another one for the transmission from
the counter-shaft to both roll-pulleys, or from one roll-pulley to the other, the
latter strap being conducted over a tension and guiding-pulley, while the main
strap is without such pulley. This system indeed allows the main driving-pulley
to be arranged in any desirable position; but it renders necessary the use of at
least five pulleys, while usually six are employed.
A further disadvantage of all the existing systems is this, that the shafts of the
two rolls are pressed by the driving-straps at the opposite ends against their
bearings, and that these are consequently caused to wear out in such a manner that
the parallelism of the rolls is impaired.
Finally it may be mentioned that in mills with two pairs of rolls, the said pairs
are usually so coupled by the straps that, when from any reason one pair has to be
stopped, it is impossible to work on with the other one.

page_text: By means of our improved system of driving-gear these disadvantages are
obviated.
Referring to Figs. 1, 2 and 3, ƒ and g are the two roll-shafts carrying at their
ends being on the same side of the machine, respectively the roll-pulleys S¹ and S³,
which may be of like or different diameter. These pulleys being larger in diameter
than the rolls, are placed by the side of each other with a small space between
them. S is the driving pulley keyed on the line of shafting T, and a the guiding
pulley. From the driving-pulley S the strap runs to the roll-pulley S³, thence
over the guiding-pulley d, from the same around the second roll-pulley S¹ and back
to the pulley S. The guiding-pulley & is placed, in respect to the pulleys S¹ and S³,
obliquely in such a manner that the strap coming from S³, will run properly upon
the same, and that, as it leaves the pulley d, it will likewise be caused to run on
the pulley S¹ in the manner required in strap-gearing.
The said guiding-pulley d rotates on an axle mounted on an arm or carrier b,
and which, on account of the described position of the pulley, is arranged at an
angle to the shafts ƒ and g. Preferably this axle consists in a pin c made with a
part c¹ forming an angle with c; the said part c² being inserted into the carrier b
in a position parallel to the shafts ƒ and g, and having at its end a screw-thread
with nut for securing it, so that when the said nut is slackened the pin c may be
turned on its part c¹ for the purpose of adjustment of the pulley d to the requisite
angular position in respect to the pulleys S¹ and S³. Another mode of attachment
of the pin c to the carrier b is shown by Fig. 4. In this case a spherical collar h
The said
is formed upon the pin c, and its part c¹ is arranged in a line with c.
collar engages in a recess in the carrier b, while on the end of the part c' is placed
a large washer i fitting to a recessed spherical boss on the carrier b. This arrange-
ment allows the pin c to be adjusted within certain limits to any desired angle,
while by means of the disposition described first, the adjustability of the pin is
limited to its rotation on the surface of a cone having the centerline of the part c¹
for its axis.
.
The carrier b is so constructed that it may be rotated about an axis parallel to
the shafts f and g, or coinciding with one of them. According to the drawing the
said carrier is, for this purpose, made with an annular part with which it is slipped
on a flanged ring or circular body a, permanently fixed to the frame of the machine,
and it is secured to the ring by a plate a¹, adapted to press on the annular part of
the carrier b, and by screw-bolts passed through the ring a and the plate a¹. When
the nuts of the said bolts are slackened, the carrier 6 with the pulley d may be
turned on the ring a and the strap thereby tightened, the said pulley being thus
also made servicable as tension-pulley.
In respect to the cooperation of the driving-pulley S with the two roll-pulleys S¹
and S, which are placed by the side of each other, it requires to be observed that
the two strap-parts passing respectively from S' to S and from S to S³, do not run
with their centerlines (or their edges) in a plane parallel to the planes of the
pulleys. If the pulley S is at a considerable distance from the pulleys S¹ and S²,
this deviation of the strap-parts from their true course may be counterbalanced,
and the danger of the strap slipping off the pulleys avoided, by making the pulley S
sufficiently convex, and by placing it with its central plane opposite to the middle
.of the space between the pulleys S¹ and S³. But, if the distance of S from S¹
and S2 is small, it is preferable to make the pulley S conical and to mount it on
the driving-shaft so that it will be opposite to the pulley S2, which is to receive
the strap from S, and that its largest diameter will be in a plane with the edge
of S³ that is turned away from SI, as is shown by Fig. 5. In consequence of this
arrangement and the known tendency of a strap when passing around a conical
pulley, to run towards the thicker end of the same, the strap leaving the pulley S¹
at an angle, and likewise running in an oblique direction upon S, will be maintained
on S during its course around this pulley, and it will thereupon run straight upon
the pulley S. It is, however, advantageous to make the pulley S somewhat wider

page_text: than the other pulleys, and in the case of the arrangement shown by Figs. 5 and 6,
it is advisable to slightly bevel the pulley S at its thick end.
The advantages which the described driving gear presents are: Firstly, it allows
the mill provided therewith to be placed in any desired position relatively to the
driving-shaft T, provided, of course that the roll-shafts be parallel to the shaft T.
This will be seen especially from Fig. 7. Secondly, separate straps which are not
kept tight by a tension-pulley, are avoided. Thirdly the number of pulleys is
reduced as much as is at all possible, i.e. to four. Fourthly, the pull of the strap
acting in like direction and on like ends of the roll-shafts, the wear of the bearings
of the said shafts resulting from such pull will not affect the parallelism of the rolls.
Fifthly, in mills with two pairs of rolls as shown in Fig. 3, each pair may be driven
independently of the other one, so that either of them may be stopped while the
other pair continues to operate.
In the foregoing description the means for transmitting motion from the pulley S
to the pulleys S¹ and S₁ has been supposed to be a strap. Instead of the same,
however, any other flexible and suitable power-transmitting medium, such as a
rope or a plurality of parallel ropes, may be employed, provided only that the rims
of the pulleys be formed in corresponding manner as is universally known.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :
1. In machines having two parallel shafts ƒ and g provided at the like ends
respectively with the pulleys S₁ and S' arranged in different planes, the combination,
with the said pulleys and a driving-pulley S, of a tension and guiding-pulley d
placed obliquely to the pulleys S¹ and S³, and a strap or its described equivalent,
running from the driving-pulley S over the pulleys S¹ and S and the pulley d,
substantially as and for the purpose described.
2. The combination, with the parallel shafts ƒ and g, provided with the pulleys S¹
and S, arranged in different planes, the driving-pulley S, and a strap or its
described equivalent, of a tension and guiding-pulley d rotating on an axle that
forms an angle with the shafts f and g, the said axle being mounted on a rotatively-
adjustable carrier b, substantially as specified.
3. The combination with the parallel shafts ƒ and g provided with the pulleys S¹
and S, arranged in different planes, a tension and guiding-pulley & placed obliquely
to the pulleys S¹ and S³, and a strap running over the said pulleys, of a conical
driving-pulley S, as and for the purpose set forth.