Improved Method of and Apparatus for Forming, Rolling, and Finishing Metals.
Year: 1891

page_text: Date of Application, 6th Mar., 1891
Complete Specification Left, 1st Dec., 1891-Accepted, 6th Feb. 1892
PROVISIONAL SPECIFICATION.
Improved Method of and Apparatus for Forming, Rolling, and
Finishing Metals.
I MAX MANNESMANN, of Komotau, in the Kingdom of Bohemia, Engineer, do
hereby declare the nature of this invention to be as follows:-
The present invention relates to a method and apparatus for forming, rolling,
smoothing and finishing metals in which the metal under operation receives a step by
step forward motion combined with a retrograde motion as compared with continuous
forward motion in existing rolling processes, the rolls being so arranged as to
operate upon only a comparatively short length of the metal during a portion of their
revolution, whereupon the metal receives a certain motion in the contrary direction,
the rolls being either made to revolve in the contrary direction also, or to continue
to revolve in the same direction and to operate upon the metal again when this is
again moved in the direction of the motion of the rolls. The metal is conse-
quently not operated upon consecutively along its whole length, but only piece by
piece, the place of operation being made as it were, to advance step by step from
one end of the metal to the other. Whereas, with the existing rolling processes
the metal under operation is shaped by being worked upon by means of a greater
or smaller number of calibres, and by being caused to pass repeatedly through
the rolls and after passing through a calibre, being always brought to the front of
the rolls again, according to the present invention the metal always remains between
the rolls so that it only has to perform comparatively small longitudinal movements.
If the end of the metal at which the operation is commenced be termed the front
end, and the other the rear end and the movement from the rear to the front end be
called the "forward motion" while the reverse motion is termed the "backward
motion," then the working of the metal can be effected either only during the forward
motion or a portion of the same or only during the backward motion or a portion of
the same; or again, it may be worked during both the forward and the backward
motion.
In working cylindrical or prismatic bars, wire and the like, rotation of the
metal is sometimes required after each action of the rolls thereon in order that other
portions of the metal may be acted upon by the rolls. Flat metal objects and sheet
metal require no such turning. The rolls employed for carrying out this process
may either have a continuous rotation in the same direction or they may have a to
and fro or reciprocating motion; only in the latter case can the metal be operated
upon both during the forward and the backward motion. In any case the rolls
may have calibres of concentric form or of tapering form, or both concentric and
tapering form. If the rolls are only to be used for finishing, that is to say only to
effect moderate alterations of the sectional form it is sufficient to make the projecting
concentric parts thereof quite concentric and to provide them with a somewhat
rounded edge.
The process is carried out in a most simple manner with a pair of rolls having parallel
axes, but three or more rolls can be employed which form the calibre between them
and whose axes consequently are situated in one and the same plane and form for
With four rolls in one
example angles of 60 degrees or 90 degrees with each other.
plane all four can be made to work together, or one pair can work forwards and the
other pair backwards. With a single pair of rolls, these may be placed one above
the other, or side by side with horizontal or vertical axes, or in any other suitable
manner. Also; in a similar manner, as with universal rolls, two or more pairs of
rolls arranged one behind the other, or groups thereof may be employed, which
operate simultaneously or alternately upon the metal, in which case either both
pairs of rolls act upon the metal in the same direction or the one pair acts thereon

page_text: in the one direction and the other in the opposite direction. Under certain circum-
stances such a rolling mill can be so arranged that rotation of the metal is rendered
unnecessary.
The calibres can be made to run in a helical line, or straight calibres may be
arranged side by side with their commencements lying on a helical line; also, the
separate calibres may be arranged in steps, or the following calibres may be
widened or narrowed.
In order to render possible the movement or turning of the metal at the time
when no rolling action is being effected thereon, the rolls are provided with corre-
sponding gaps or flat faces, if the metal is not freed by moving the rolls from each
other. By altering the position of the rolls or the above described step by step
motion during the rolling of a bar of metal it is possible to modify the cross-section at
various points of the longitudinal axes of the metal, and consequently to produce
bodies such as connecting rods, bearers, struts and the like, having equal strength
throughout their length. The process can also be interrupted periodically, after
working a certain length of the object, if this is to be of stepped form. The move-
ment of the metal under operation in the longitudinal direction can be effected
either by means of the rolls themselves that act upon it or by special mechanical
appliances. This is determined according to the various modes of carrying out the
process or according to the nature of the metal object under operation.
I will proceed to describe various modifications of the process by means of
diagrammatic figures on the accompanying drawings, the mode in which the rolls
are driven and the metal under operation is fed forward being left out of con-
sideration.
Figs. 1 to 8 of the drawings show therolling of a bar-shaped metal object by
means of rolls that are rotated continuously in the same direction and it is assumed
that the action of the rolls upon the metal takes place during the forward motion
thereof, the rolls being made with increasing calibres to which are added concentric
calibre portions for the purpose of smoothing the worked parts. The rolls A and B
driven in any suitable manner, are rotated continuously in the direction of the
arrows 1 and 2, and have in addition to the calibres, shewn by way of example in
front view Figs. 12, 13 and 14, gaps or flat places a which permit of the backward
motion of the metal object W, when this has to be brought into a new commencing
position for being acted upon by the rolls.
Figs. 1 shows such a commencing position, the object W is advanced in the
direction of the arrow 3 towards the rolls A and B (forward motion) to such an
extent that its front end is gripped by the rolls and is so acted upon by them in
the manner shown in Figure 2 until the gaps a of the rolls come into position
opposite each other as at Figure 2. The rolls then cease to act upon the metal and
the metal can now be moved backwards in the direction of the arrow 4 (backward
motion) as it is entirely freed by the rolls A and B. During this backward motion
a rotation of the object W round its longitudinal axis in the direction of the arrow 5
can be effected so that at the next action of the rolls other parts of the section of the
metal will be operated upon. The extent of the gaps a of the rolls has to be so
made in proportion to the backward motion of the object, that such motion is not
affected by the rotation of the rolls. As furthermore the metal moves free between
the rolls during such backward motion, it follows that it must be suitably guided
and supported in the direction of its longitudinal axis as will be explained further
on. After the completion of the backward motion of the metal Fig. 3 the rolls can
act upon it again whereby a further working of the metal is effected as indicated
at Figure 4 until the rolls have again turned into such a position that the
gaps a are opposite each other. During this part of the rotation of the rolls A
and B the metal can be moved back again in the direction of the arrow 4 as
described in reference to Fig. 2 and be turned round its longitudinal axis so
as to be brought into suitable position for the further action of the rolls. As will be
seen on comparing Figs. 1 and 3 the metal at each attack of the rolls is gripped
by a narrower portion of their calibres. If the rolling has proceeded so far that

page_text: the rolls can act upon the metal at the smallest section of their calibre, any further
reduction of the section of that part of the metal cannot take place so that at the
following rolling operation the thicker portion of the metal situated behind that
point will not have its diameter or thickness further reduced, and the front end
of the metal will become cylindric or prismatic as shown at Fig. 5. The following
backward motion of the metal is consequently effected in such a manner, that
the metal is only moved back to a point where the rolls at the next following
attack will seize the conical part of the metal, while the cylindrical or prismatic end
thereof remains between the rolls, as shown at Figs. 5 and 6. From this point, at
each attack of the rolls, the cylindrical or prismatic part of the metal will be
extended. If the forward and backward motions of the metal object in the direc-
tion of the arrows 3 and 4 be drawn out as at Fig. 7, it will be seen how the metal
object will have to be moved forward during the rolling process in a periodically
retrograding manner. The small curved arrows in this figure show the attack of
the rolls during the forward motion of the metal object in the direction of the
arrows 3. To the smallest section of the calibre of the rolls is added advantageously
a concentric portion of the calibre as indicated in all the figures so that on passing
through this portion of the calibre a smoothing of the rolled metal is effected, and
when finished it thus leaves the rolls in a perfect condition in the form of a
cylindrical or prismatic body, as shown at Figure 8. Instead of causing the rolls
to attack the metal during the forward motion thereof, this may also be effected
during the backward motion. Figure 9 shows, by way of example, the completion
of such an attack in which the concentric part of the calibre is already in action.
The rolls A and B rotate in the direction of the arrows 6 and 7. When the
gaps a of the rolls arrive opposite each other, as at Fig. 10, the metal object
can be moved freely forward again in the direction of the arrow 9, so that a
In this
farther portion of the metal presented to the further attack of the rolls.
case therefore the forward motion will also be greater than the backward motion
so that the periodically retrograding step by step motion shewn at Figure 11 will
be obtained, but whereas in the former case the attack of the rolls commenced
at the smaller diameter of the metal object, in this case it will begin at the larger
diameter. Thus when the rolls attack the metal during the forward motion, as at
Figure 7, a rolling out of the thin end of the metal object towards the thicker end
is effected, while when the rolls attack the metal object during the backward
motion, as at Figure 11 the rolling out of the metal, is effected from the thicker
towards the thinner end as will be readily seen. The calibre of the rolls is of course
determined by the section which is to be imparted to the metal object. With a
circular calibre as at Figure 12 one portion thereof is made oval, whereas the
concentric part, which serves to smooth the metal, is formed of semicircular section.
If the section of the metal object is not circular but polygonal the tapering part of
the calibre can also be correspondingly formed, as shewn at Fig. 13 for a rectangular
section or only the concentric part of the calibre, which serves to smooth the metal,
may have the configuration which it is desired to impart finally to the metal object,
the tapering part of the calibre being either semicircular or oval as at Figure 14.
Both parts of the calibre are in this case made to die into each other.
If the section of the metal object is not circular after working the angle through
which the metal is turned after each attack of the rolls, cannot be optional, but
must be made corresponding to the section so that, in the case of a square section,
the metal must be turned each time 90 degrees, with au hexagonal section 60 degrees
or 120 degrees. If the section does not form a regular polygon, the rolls are formed
with several working parts and a corresponding number of gaps. Figs. 15 and 16
show respectively a cross-section and end view of such pair of rolls for rolling a
prismatic bar of rectangular section. The two calibres of the rolls A and B
When the two
serve for rolling the bar W when placed on edge as at Figure 16.
gaps a are opposite each other, the backward motion of the object is effected and
at the same time it is turned through an angle of 90 degrees. The bar will then
lie in a flat position and will be acted upon by the calibres ¹ until the gaps a¹ come

page_text: opposite each other. During the backward motion of the bar it is again turned
through 90 degrees. Fig. 17 shows the developed calibre k¹ and the end section
thereof, the profiles to be rolled being indicated by dotted lines. Fig. 18 shows a
front view of a pair of rolls for rolling a flat bar, the edges of which are provided
with longitudinal swellings. In this case also the rolls A and B have two
calibres k¹ which are shown developed in Figs. 19 and 20 with the end sections
thereof. With assymetrical sections, for instance that shown at Fig. 21, more
than two acting parts may in certain cases be required, and with such sections also
a backward turning of the bar may be necessary instead of the bar being always
turned in the same direction after each rolling operation. Such.a construction of
rolls with several acting parts and gaps may however also be employed with
advantage for rolling cylindrical bars. In order to render the attack of the rolls
more reliable, it is of advantage, in certain cases to form the working parts with
toothed or stepped projections . Figure 15 which grip the metal object with a
greater amount of friction and consequently drag it more effectually through the
rolls. The above described process may be variously modified according to the
purposes to which it is to be applied, some of which have already been mentioned.
As the rolls only act upon the metal object during a portion of their revolution, it
follows that it is not at all necessary to cause them to perform complete revolutions,
but that the rolls may have a backward and forward motion imparted to them.
Also in this case as described the rolls may be made to act upon the metal either
only during the forward motion or only during the backward motion. Such rolling
mill with reciprocating motion of the rolls may however be so arranged that both
at the forward motion and at the backward motion of the metal object the rolls
are made to act thereon, whereby a considerably quicker mode of working may be
attained. This mode of working is shown at Figs. 22 to 29. The mode of
proceeding when the rolls are in the working position at the beginning of the
operation as at Fig. 22 corresponds exactly with that described with reference to
Fig. 1, the rolls A and B revolving in the direction of the arrows 1 and 2 seize the
metal object W moving forward in the direction of the arrow 3.
As soon as the rolling operation is completed and the gaps a liberate the metal
object W as at Fig. 23, the rolls come to a standstill and the metal object is then
moved forward in the direction of the arrow 11 so as to assume the dotted position,
it being if necessary at the same time turned on its longitudinal axis in the direction
of the arrow 5 so that the rolls A B at the following return motion in the direction
of the arrows 6 and 7 will at once seize the metal object at its thicker part and
move it backward in the direction of the arrow 12. While therefore in the former
operation the rolls were made to act from the thinner to the thicker end of the
metal, they now begin to operate in the contrary direction until they arrive in a
position at Fig. 24 in which the action of the rolls on the metal object ceases and
the gaps a allow of a forward motion (and if necessary also rotation) of the metal
object in the direction of the arrow 13, as shown at Fig. 24 in dotted lines. In
this position the metal object W is ready for the renewed attack of the rolls A
and B when these again rotate in the direction of the arrows 1 and 2. The metal
object is then again moved in the direction of the arrow 3, so that at the end of
this period the position shown at Fig. 25 will be reached in which a small forward
motion (and if necessary rotation), of the metal object is effected until it arrives
in the working position for the attack of the rolls on their rotation in the direction
of the arrows 6 and 7. In this way the rolling operation proceeds as indicated in
Figs. 26, 27 and 28 in various stages of the process and which require no further
explanation. If the travel performed by the metal object during its passage
through the rolls be again indicated by a broken line as at Fig. 29, it will be seen
that it again constitutes a step by step forward motion with partial retrogression.
For the sake of clearness the several parts of the forward and backward motion
in thus figure are represented drawn apart, but in reality the movements 13. 3
and 11 can run one into the other or directly follow each other, when they are
brought into proper relation to the reversing motion of the rolls. Consequently a

page_text: simple step by step forward motion with partial retrogression is produced which
only differs from that described with reference to Figs. 7 and 8 that a forward
motion at each two attacks of the rolls is increased by the motion 11 and 13
whereby as already observed a considerably more rapid rolling is effected. The
rolls need not in this case be formed as complete cylinders at the sides of the
calibre, Fig. 12 but it is quite sufficient to form them as segments, that is to say,
to form only those portions cylindrical which roll upon each other during the
reversing motion. Although such forms cannot strictly be called rolls I will
retain this designation as the working of the metal object is still effected by a rolling
motion thereof.
In place of rolls with tapering and concentric calibres with gaps such with concentric
calibres without gaps may be used if the rolls be so arranged that at each attack
on the metal object they are made to approach each other or to recede from
each other. This operation is particularly advantageous when large pieces of
work have to be rolled. The adjustment of the rolls may be advantageously
effected by means of hydraulic cylinders and plungers which carry the bearings of
the lower rolls, as indicated at Figs. 30 to 34, for rolls with reciprocating motion
for working a plate W. If the rolls A and B work in the direction of the
arrow 3. Fig. 30, during the forward motion of the plate W the lower roll sinks
somewhat in the direction of the arrow 14, the plunger F of each lower bearing
being made to move downwards in its cylinder G. The plunger F is made to
perform a motion in the contrary direction as shown by the arrow 15. Fig. 31,
when the rolls act upon the metal during the backward motion thereof in the
direction of arrow 12. Figs. 32 to 34 show the further progress and completion of
the rolling operation.
If bars with circular sections have to be rolled, the rolls are formed with oval
calibres and after each rolling action rotation of the bar on its longitudinal axis
is necessary, for which purpose the rolls have to be moved so far apart as to allow
of the fice shifting and turning of the bar. Also, bodies whose section is a
regular polygon can be rolled out in this manner. The necessary greater distance
between the rolls required at the commencement of the rolling may be effected
by the adjustment of the upper roll bearings in the known manner by means of
screw spindles and toothed gearing. The movement of the plunger F is effected
by suitable liquid under pressure in the cylinder G. The bearings of the one roll
may however be adjusted by a mechanical device such as a lever acted upon by
an eccentric or cam, or by means of a wedge motion as at Fig. 35, where the
wedges D of the two bearings are moved to and fro by means of a crank shaft
which has the action, as will be readily understood from the foregoing, of raising
and lowering the lower roll. The upper roll might be raised and lowered in the
same manner during the operation of rolling the lower rolls being either stationary
or also raised and lowered.
If two or more pairs of rolls are arranged one behind the other, the axes of
the one pair may either be arranged horizontally while those of the other pair
are arranged vertically, as shewn in Fig. 36 or the axes of both pairs may be hori-
zontal as at Fig. 37, in the first named case any rotation of the metal object is
superfluous. If as indicated by the arrows in Fig. 37, the one pair of rells A B
is made to operate during the backward motion of the metal object while the
other pair A B is made to act during the forward motion thereof, the move-
ment of the metal object may be effected entirely by the rolls so that the metal
object will be moved to and fro thereby. The rotation of the rolls must, in this
case, be so regulated that the one pair of rolls frees the metal object as soon as the
other pair begins to act.
For effecting the step by step forward motion with periodical retrogression the
forward motion of the metal object is made somewhat greater than the backward
motion. It is to be understood that with the rolling mill Fig. 37 on every change
of motion rotation of the metal object must be effected if it is of a circular
or polygonal cross-section in a similar manner to ordinary rolling mills; the rolls of

page_text: the above described construction may be provided with several calibres formed in
it side by side in which the rolling operation may be carried out either
simultaneously or consecutively. In this case it is advantageous to arrange the
working portion k (Fig. 15) of one calibre in line with the gap a (Fig. 15) and the
contiguous calibre so that one rod is being acted upon while the contiguous rod is
being moved backwards during the rest. In order that the metal object may be of
equal thickness at all points of its longitudinal axis it is necessary that at the end
of each rolling action the distance apart of the roll axes shall be equal, or that the
return movements shall always be equal. If however during the rolling such
distance be gradually altered, which may for instance be effected by turning the screw
spindles for adjusting the bearings of the upper roll the metal object will be formed
conical or conoidal or pyramidal. This actuation of the screw spindles or of their
gearing may be easily effected by a ratchet motion that is actuated by one of the
rolls or otherwise. With an equal adjustment for each rotation of their rolls the
configuration of the metal object will become conical or in the case of a polygonal
cross-section, similar to the frustrum of a pyramid. If on the other hand the
amount of adjustment be altered for each revolution the metal object will become
conoidal or of curvet configuration. If the rolls are made to approach each other
during the rolling, the back end of the metal object will become thinner than the
front end. The reverse effect will be produced if the rolls are gradually moved
apart. By combination of the two methods a body will be produced that is
thinner at the ends than in the middle, thus for instance producing a form of equal
resistance against transverse strain. There will be no difficulty in effecting
by suitable actuation of the adjusting screw spindles of the rolls, to obtain any
desired alteration in the cross-sections with reference to the longitudinal axis of the
body. The same process can also be employed in the to and fro movements but in
this case similar results can be obtained by altering the reverse motion as by
altering the position of the rolls, or the two methods may be employed in combina-
tion. This will readily be seen if it is considered that the outer configuration
If now
of the metal object is governed by the final positions of the rolls, lig. 28.
the return motion of the rolls is so altered that in place of the narrower part o of
the calibre, by degrees the larger part o' is made to act, towards the end of each
operation, upon the metal object, a gradual increase of the cross-section in the
direction of the length will result. In a similar manner a reduction of the section
may be produced by gradually causing smaller portions of the calibres to act upon
the metal object towards the end of each rolling process. The guiding and
movement of the metal object will have in most cases to be effected independently
of the rolls that act upon it. In working bodies of plate form or sheet metal,
however, the said step by step and retrograde motion may be effected by the
rolls alone if they are formed with concentric calibres and are moved as indicated
at Figs. 30 to 35. The small shiftings 11 and 13 Fig. 29 are in that case dispensed
with, and it is only necessary to cause the rolls to turn somewhat more during the
If there-
forward motion of the metal object than during the return motion.
fore by way of example the rolls are driven by a reversing steam engine with toothed
gear transmission the reversal of the engine is so arranged that the motor, for
instance, turns each time 4 times in the forward direction, but only 3 times in
the backward direction. If the rolls are then pressed with sufficient force against
the metal object so as to move it forward or backward by frictional contact
no further device for moving the metal object will be required. For guiding the
same, the ordinary roll tables will plane surfaces or with guide rollers will be
sufficient. If on the other hand the metal object has to receive a certain shifting
motion for carrying out the above described process, such shifting can be effected
in a great variety of ways. In the process described with reference to
Figs. 11 and 29 for example the forward motion of the metal object which is
required in order to bring it under the action of the rolls may be effected by
means of weights or by springs. A more reliable result, however, will be obtained
if a positive motion is imparted to the metal object, this being effected either by

page_text: means of pairs of feed rollers, either in front of or behind the rolls, or by gripping
apparatus. When using pairs of guide and feed rollers in front of or behind the
rolls, the former have the necessary reverse motion imparted to them in such
manner that the desired step by step forward motion, with retrogression of the
metal object is produced. The required rotation of the metal object can in this
case be simultaneously obtained by placing the guide rollers in oblique positions.
The rotation of the metal object during the rolling operation can also be effected
automatically by arranging the axis of the rolls somewhat obliquely relatively to
each other. The metal object can in that case be brought back without rotation
into the original position during the period of rest in order again to be rolled and
simultaneously turned. The guiding and feed of the metal object by means of
grippers is more complicated. Figs. 38 39 and 40 show such an arrangement in
side view, front view and plan. The metal object W to be operated upon has a
rectangular cross-section and is seized on each side of the rolls A and B by means
of grippers M and N which are guided in the direction of motion of the metal
object by means of guides I fixed to the sides of the housings S. Each gripper
consists of a lower cheek and upper cheek. The lower cheeks d are provided
at each end with trunnions d' which slide in the guides II. The lower cheeks of
both grippers M and N are connected together by means of rods P situated outside
the housings S so that a rigid frame is formed by the parts
and f These lower
cheeks d constitute the support for the metal object W and the trunnions d' of the
cheeks of the gripper H are connected by links g with the levers g of the shaft g²
which is moved to and fro by the connecting rod of the crank h¹ fixed to the
lower roll B. The upper check is guided in the frame shaped guides d' fixed to
the lower cheek & Fig. 41 and is always pressed downwards by means of springs c
situated in so that the metal object W is nipped between the two cheeks and
by the action of the springs c and is thus made to participate in the to and fro
motion of the grippers M and N. As shewn in Fig. 7 however the backward
motion must be smaller than the forward motion of the metal object and the
cheeks d and must consequently only move the metal object during a portion of
their backward motion, the action of the springs must therefore be partially
counteracted during the backward motion. This is effected by means of the cam
shaft which is carried by the trunnion and the guides and is provided with
cams Fig. 41 which act upon rollers on the lower ends of rods f¹ connected
to the cheek. By a rotation of the shaft in the direction of the arrow Fig. 41
the upper cheek is raised and the metal object is consequently freed. The
rotation of the shaft of the gripper N is effected by means of the lever iª
connected to the shaft Fig. 38 which lever is connected by links with an
extension of the connecting rod h. By the varying positions of the connecting
rod on the rotation of the roll B the lever 12 of the shaft will receive an unequal
to and fro motion as shown in the diagram Fig. 42 representing some of the
principal positions of the crank h. The cains are so proportioned that towards
the end of the backward motion the upper check of the gripper N will be raised
and this motion of the shaft of the gripper N is transferred by arm Fig. 39
rod and arm 16 Fig. 40 to the shaft of the gripper M consequently the metal
object will be simultaneously released by both grippers so that it will be carried
back by these only during a portion of their backward motion. This raising of
the upper cheek could also be effected by inclined planes p Fig. 43 which are
connected adjustably to the guides H and on which the rollers on the lower ends
of the rods run towards the end of the backward motion of the grippers.
Figs. 44, 45 and 46 show in side view, front view and plan a rolling mill for rolling
bodies with circular cross-section. In this case also the metal object W is seized and
guided on both sides of the rolls A and B mounted in housings S this being effected by
means of grippers m mounted rotatably in the cross barst Fig. 46 connected together
by rods P so as to form a rigid frame. The grippers m consist, as shown at
Figs. 47 and 48, of a frame m carried by a hollow trunnion in which frame slide
two cheeks a which are pressed against the metal object W by springs e and are
2

page_text: I
thus made to hold it with a certain force. The hollow trunnion of each gripper m
has connected to it a toothed pinion with which gears a toothed pinion s whose
hollow trunnion s¹ is also mounted rotatably in the cross bar t. Within the hollow
trunnions is a sleeve 2 Figs. 49 and 50 which slides upon the rod u carried by the
guides II when the cross barst have a to and fro motion imparted to them through
the shaft reciprocating lever connecting links y' and connecting rod actuated
by crank on the lower roll B. On the rod u Fig. 46 is formed a helical groove u¹
into which takes a feather on the sleeve s2 so that on to and fro motion being
imparted to s² the latter receives at the same time a partial rotary motion. This
rotation is transmitted to the hollow trunnion s¹ through the ratchet wheel s³ fixed
to and the pawls carried by the hollow trunnions the rotary motion of the
latter being transmitted by pinions & and to the gripper m.
According as the rolling-mill is to operate as described with reference to Fig. 7 or
with reference to Fig. 11, there will be effected during the backward or forward
motion of the metal object a simultaneous rotation of the latter whereas the
pawls slides loose over the teeth of the ratchet wheel 3 at a time when the metal
object is being operated upon by the rolls, and consequently no rotation round
the longitudinal axis is to be effected. The forward motion of the frame formed
by the cross bars and rods P and which holds the metal object by means of
the grippers
m is in this case just as great as the backward motion.
In order that the step by step forward motion with retrogression of the metal
object can be effected, there must be provided means whereby the rolls A and B in
operating upon the metal object cause this to shift somewhat in the grippers during
the rolling operations. For enabling this to be done, the pressure of the spring
which presses the cheeks n against the metal object must be correspondingly
controlled. The mechanism for the movement and guiding of the metal object can
be effected in various other ways. It will mostly be dependent upon the nature of
the metal object, and the described arrangements are therefore only intended
to serve as examples for carrying out the process.
Dated this Sixth day of March 1891.
ABEL & IMKAI,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Method of and Apparatus for Forming, Rolling, and
Finishing Metals.
I, MAX MANNESMANN, of Komotau, in the Kingdom of Bohemia, 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:-
The present invention relates to a method and apparatus for forming, rolling,
smoothing and finishing metals in which the metal under operation receives a step
by step forward motion combined with a retrograde motion as compared with
continuous forward motion in existing rolling processes, the rolls being so arranged
as to operate upon only a comparatively short length of the metal during a portion
of their revolution, whereupon the metal receives a certain motion in the contrary
direction, the rolls being either made to revolve in the contrary direction also, or to
continue to revolve in the same direction and to operate upon the metal again when
this is again moved in the direction of the motion of the rolls. The metal is
consequently not operated upon consecutively along its whole length, but only piece
by piece, the place of operation being made as it were, to advance step by step from
one end of the metal to the other. Whereas, with the existing rolling processes
the metal under operation is shaped by being worked upon by means of a greater
or smaller number of calibres, and by being caused to pass repeatedly through the
rolls and after passing through a calibre, being always brought to the front of the

page_text: rolls again, according to the present invention the metal always remains between
the rolls so that it only has to perform comparatively small longitudinal
movements.
"
If the end of the metal at which the operation is commenced be termed the front
end, and the other the rear end and the movement from the rear to the front end
be called the "forward motion" while the reverse motion is termed the "backward
motion then the working of the metal can be effected either only during the
forward motion or a portion of the same or only during the backward motion or a
portion of the same; or again, it may be worked during both the forward and the
backward motion.
In working cylindrical or prismatic bars, wire and the like, rotation of the metal
is sometimes required after each action of the rolls thereon in order that other
portions of the metal may be acted upon by the rolls. Flat metal objects and
sheet metal require no such turning. The rolls employed for carrying out this
process may either have a continuous rotation in the same direction or they may
have a to and fro or reciprocating motion; only in the latter case can the metal be
operated upon both during the forward and the backward motion. In any case the
rolls may have calibres of concentric form or of tapering form, or both concentric
and tapering form. If the rolls are only to be used for finishing, that is to say only
to effect moderate alterations of the sectional form it is sufficient to make the
projecting concentric parts thereof quite concentric and to provide them with a
somewhat rounded edge.
The process is carried out in a most simple manner with a pair of rolls having
parallel axes, but three or more rolls can be employed which form the calibre
between them and whose axes consequently are situated more or less in one and the
same plane and form for example angles of 60 degrees or 90 degrees with each
other. With four rolls in one plane all four can be made to work together, or one
pair can work forwards and the other pair backwards. With a single pair of rolls
these may be placed one above the other, or side by side with horizontal or vertical
axes, or in any other suitable manner. Also in a similar manner, as with universal
rolls, two or more pairs of rolls arranged one behind the other, or groups thereof
may be employed, which operate simultaneously or alternately upon the metal, in
which case either both pairs of rolls act upon the metal in the same direction or the
one pair acts thereon in the one direction and the other in the opposite direction.
Under certain circumstances such a rolling mill can be so arranged that rotation of
the metal is rendered unnecessary.
The calibres can be made to run in a helical line or circular calibres may be
arranged side by side with their commencements lying in a helical line; also, the
separate calibres may be arranged in steps, or the following calibres may be widened
or narrowed.
In order to render possible the movement or turning of the metal at the time
when no rolling action is being effected thereon, the rolls are provided with corre-
sponding gaps or flat faces, if the metal is not freed by moving the rolls from each
other. By altering the position of the rolls for the above described step by step
motion during the rolling of a bar of metal it is possible to modify the cross
section at various points of the longitudinal axes of the metal, and consequently to
produce bodies such as connecting rods, bearers, struts and the like, having equal
strength throughout their length. The process can also be interrupted periodically,
after working a certain length of the object, if this is to be of stepped form.
movement of the metal under operation in the longitudinal direction can be effected
either by means of the rolls themselves that act upon it or by special mechanical
appliances. This is determined according to the various modes of carrying out
the process or according to the nature of the metal object under operation.
The
I will proceed to describe various modifications of the process by means of
diagrammatic figures on the drawings accompanying my Provisional Specification, the
mode in which the rolls are driven and the metal under operation is fed forward
being left out of consideration,

page_text: Figures 1 to 8 of the drawings show the rolling of a bar-shaped metal object by
means of rolls that are rotated continuously in the same direction and it is assumed
that the action of the rolls upon the metal takes place during the forward motion
thereof, the rolls being made with increasing or excentric calibres or grooves to
which are added concentric calibre portions for the purpose of smoothing the
worked parts. The rolls A and B driven in any suitable manner
are rotated
continuously in the direction of the arrows 1 and 2, and have in addition to the
calibres, shewn by way of example in front view Figures 12, 13 and 14, gaps
or flat places a which permit of the backward motion of the metal object W,
when this has to be brought into a new commencing position for being acted upon
by the rolls.
Figures 1 shows such a commencing position, the object W is advanced in
the direction of the arrow 3 towards the rolls A and B (forward motion) to such
an extent that its front end is gripped by the rolls and is so acted upon by them
in the manner shown in Figure 2 until the gaps a of the rolls come into
position opposite each other as at Figure 2. The rolls then cease to
act upon the metal and the metal can now be moved backwards in the
direction of the arrows 4 (backward motion) as it is entirely freed by the
rolls A and B. During this backward motion a rotation of the object W
round its longitudinal axis in the direction of the arrow 5 can be effected
so that at the next action of the rolls other parts of the section of the
metal will be operated upon. The extent of the gaps a of the rolls has to be
so made in proportion to the backward motion of the object, that such motion
is not affected by the rotation of the rolls. As furthermore the metal moves
free between the rolls during such backward motion, it follows that it must be
suitably guided and supported in the direction of its longitudinal axis as will
be explained further on. After the completion of the backward motion of the
metal Figure 3 the rolls can act upon it again whereby a further working of the
metal is effected as indicated at Figure 4 until the rolls have again turned into
such a position that the gaps a are opposite each other. During this part of
the rotation of the rolls A and B the metal can be moved back again in the
direction of the arrow 4 as described in reference to Figure 2 and be turned
round its longitudinal axis so as to be brought into suitable position for the
further action of the rolls. As will be seen on comparing Figs. 1 and 3 the
metal at each attack of the rolls is gripped by a narrower portion of their
calibres. If the rolling has proceeded so far that the rolls can act upon the
metal at the smallest section of their calibre, any further reduction of the section
of that part of the metal cannot take place so that at the following rolling
operation the thicker portion of the metal situated behind that point will not
have its diameter or thickness further reduced, and the front end of the metal
will become cylindrical or prismatic as shewn at Fig. 5. The following back-
ward motion of the metal is consequently effected in such a manner, that the
metal is only moved back to a point where the rolls at the next following attack
will seize the conical part of the metal, while the cylindrical or prisinatic end
thereof remains between the rolls, as shewn at Figs. 5 and 6.
From this point,
at each attack of the rolls, the cylindrical or prismatic part of the metal will
be extended. If the forward and backward motions of the metal object in the
direction of the arrows 3 and 4 be drawn out as at Fig. 7, it will be seen how
the metal object will have to be moved forward during the rolling process in a
periodically retrograding manner. The small curved arrows in this figure show
the attack of the rolls during the forward motion of the metal object in the
direction of the arrows 3. To the smallest section of the calibre of the rolls
is added advantageously a concentric portion of the calibre as indicated in all
the figures so that on passing through this portion of the calibre a smoothing of
the rolled metal is effected, and when finished it thus leaves the rolls in a perfect
condition in the form of a cylindrical or prismatic body, as shewn at Fig. 8.
Instead of causing the rolls to attack the metal during the forward motion thereof,

page_text: this may also be effected during the backward notion. Fig. shews, by way of
example, the completion of such an attack in which the concentric part of the
calibre is already in action. The 1olls A and B rotate in the direction of the
arrows 6 and 7. When the gaps a of the rolls arrive opposite each other, as at
Fig. 10, the metal object can be moved freely forward again in the direction of the
arrow 9, so that a farther portion of the metal is presented to the further attack
of the rolls. In this case therefore the forward motion will also be greater than
the backward motion so that the periodically retrograding step by step motion
shewn at Figure 11 will be obtained, but whereas in the former case the attack of
the rolls commenced at the smaller diameter of the metal object, in this case it will
begin at the larger diameter. Thus when the rolls attack the metal during the
forward motion, as at Figure 7, a rolling out of the thin end of the metal object
towards the thicker end is effected, while when the rolls attack the metal object
during the backward motion, as at Fig. 11 the rolling out of the metal, is effected
from the thicker towards the thinner end as will be readily seen. The calibre or
groove of the rolls is of course determined by the section which is to be imparted
to the metal object. With a circular calibre as at Fig. 12 one portion thereof is
made oval, whereas the concentric part, which serves to smooth the metal, is formed
of semi-circular section. If the section of the metal object is not circular but
polygonal the tapering part of the calibre can also be correspondingly formed, as
shewn at Fig. 13 for a rectangular section, or only the concentric part of the
calibre, which serves to smooth the metal, may have the configuration which it is
desired to impart finally to the metal object, the tapering part of the calibre being
either semicircular or oval as at Fig. 14. Both parts of the calibre are in this case
made to die into each other.
If the section of the metal object is not circular after working, the angle
through which the metal is turned after each attack of the rolls, cannot be
optional, but must be made corresponding to the section so that, in the case of
a square section, the metal must be turned each time 90 degrees with an
hexagonal section 60 degrees or 120 degrees. If the section does not form a
regular polygon, the rolls are formed with several working parts and a corre-
sponding number of gaps. Figs. 15 and 16 show respectively a cross-section
and end view of such pair of rolls for rolling a prismatic bar of rectangular
section. The two calibres of the rolls A and B serve for rolling the bar W
when placed on edge as at Fig. 16. When the two gaps a are opposite each
other, the backward motion of the object is effected, and at the same time it is
turned through an angle of 90 degrees. The bar will then lie in a flat position
and will be acted upon by the calibres k until the gaps a¹ come opposite each
other. During the backward motion of the bar it is again turned through
90 degrees. Fig. 17 shews the developed calibre ¹ and the end section thereof,
the profiles to be rolled being indicated by dotted lines. Fig. 18 shews a front
view of a pair of rolls for rolling a flat bar, the edges of which are provided
with longitudinal swellings. In this case also the rolls A and B have two
calibres which are shewn developed in Figs. 19 and 20 with the end
sections thereof. With assymmetrical sections, for instance that shown at
Fig. 21, more than two acting parts may in certain cases be required, and with
such sections also a backward tuining of the bar may be necessary instead of
the bar being always turned in the same direction after each rolling operation.
Such a construction of rolls with several acting parts and gaps may however
also be employed with advantage for rolling cylindrical bars. In order to render
the attack of the rolls more reliable, it is of advantage, in certain cases to form
the working parts with toothed or stepped projections 1. Fig. 15 which grip the
metal object with a greater amount of friction and consequently drag it more
effectually through the rolls. The above described process may be variously
modified according to the purposes to which it is to be applied, some of which
have already been mentioned. As the rolls only act upon the metal object
during a portion of their revolution, it follows that it is not at all necessary to

page_text: cause them to perform complete revolutions, but that the rolls may have a back-
ward and forward motion imparted to them. Also in this case, as described,
the rolls may be made to act upon the metal either only during the forward
motion or only during the backward motion. Such rolling mill with recipro-
cating motion of the rolls may however be so arranged that both at the forward
motion and at the backward motion of the metal object the rolls are made to
act thereon, whereby a considerably quicker mode of working may be attained.
This mode of working is shown at Figs. 22 to 29. The mode of proceeding
when the rolls are in the working position at the beginning of the operation as
at Fig. 22 corresponds exactly with that described with reference to Fig. 1,
the rolls A and B revolving in the direction of the arrows 1 and 2 seize the
metal object W moving forward in the direction of the arrow 3.
As soon
as the rolling operation is completed and the gaps a liberate the
metal object W as at Fig. 23, the rolls come to a standstill and the metal
object is then moved forward in the direction of the arrow 11 so as to assume
the dotted position, it being if necessary at the same time turned on its
longitudinal axis in the direction of the arrow 5 so that the rolls A B at the
following return motion in the direction of the arrows 6 and 7 will at once
seize the metal object at its thicker part and move it backward in the direction
of the arrow 12. While therefore in the former operation the rolls were made
to act from the thinuer to the thicker end of the metal, they now begin to
operate in the contrary direction until they arrive in a position at Fig. 24 in
which the action of the rolls on the metal object ceases and the gaps a allow of
a forward motion (and if necessary also rotation) of the metal object in the
direction of the arrow 13, as shewn at Fig. 24 in dotted lines. In this position
the metal object W is ready for the renewed attack of the rolls A and B when
these again rotate in the direction of the arrows 1 and 2. The metal object is
then again moved in the direction of the arrow 3, so that at the end of this
period the position shewn at Fig. 25 will be reached in which a small forward
motion (and if necessary rotation), of the metal object is effected until it
arrives in the working position for the attack of the rolls on their rotation in
the direction of the arrows 6 and 7. In this way the rolling operation proceeds
as indicated in Figs. 26, 27 and 28 in various stages of the process and which
require no further explanation. If the travel performed by the metal object
during its passage through the rolls be again indicated by a broken line as at
Fig. 29, it will be seen that it again constitutes a step by step forward motion
with partial retrogression. For the sake of clearness the several parts of the
forward and backward motion in this figure are represented drawn apart, but
in reality the movements 13. 3 and 11 can run one into the other or directly
follow each other, when they are brought into proper relation to the reversing
motion of the rolls. Consequently a simple step by step forward motion with
partial retrogression is produced which only differs from that described with
reference to Figs. 7 and 8 that a forward motion at each two attacks of the
rolls is increased by the motion 11 and 13 whereby as already observed a con-
siderably more rapid rolling is effected. The rolls need not in this case be
formed as complete cylinders at the sides of the calibre, Fig. 12 but it is quite
sufficient to form them as segments, that is to say, to form only those portions
cylindrical which roll upon each other during the reversing motion. Although
such forms cannot strictly be called rolls I will retain this designation, as the
working of the metal object is still effected by a rolling motion thereof.
In place of rolls with tapering and concentric calibres with gaps, such with
concentric calibres without gaps may be used if the rolls may be so arranged
that at each attack on the metal object they are made to approach each other or to
recede from each other. This operation is particularly advantageously when large
pieces of work have to be rolled. The adjustment of the rolls may be advan-
tageously effected by means of hydraulic cylinders and plungers which carry the
bearings of the lower roils, as indicated at Figs. 30 to 34, for rolls with reciprocating

page_text: motion for working a plate W. If the rolls A and B work in the direction of the
arrow 3. Fig. 30, during the forward motion of the plate W the lower roll sinks
somewhat in the direction of the arrow 14, the plunger F of each lower bearing
being made to move downwards in its cylinder G. The plunger F is made to
perform a motion in the contrary direction as shewn by the arrow 15. Fig. 31, when
the rolls act upon the metal during the backward motion thereof in the direction of
arrow 12. Figs. 32 to 34 show the further progress and completion of the rolling
operation.
If bats with circular sections have to be rolled, the rolls are formed with oval
calibres and after each rolling action rotation of the bar on its longitudinal axis is
necessary, for which purpose the rolls have to be moved so far apart as to allow of
the free shifting and turning of the bar. Also, bodies whose section is a regular
polygon can be rolled out in this manner. The necessary greater distance between
the rolls required at the commencement of the rolling may be effected by the
adjustment of the upper roll bearings in the known manner by means of screw
spindles and toothed gearing. The movement of the plunger F is effected by
suitable liquid under pressure in the cylinder G. The bearings of the one roll may
however be adjusted by a mechanical device such as a lever acted upon by an
eccentric or cam, or by means of a wedge motion as at Fig. 35, where the wedges D
of the two bearings are moved to and fro by means of a crank shaft which has the
action, as will be readily understood from the foregoing, of raising and lowering
the lower roll. The upper roll might be raised and lowered in the same manner
during the operation of rolling, the lower rolls being either stationary or also raised
and lowered.
If two or more pairs of rolls are arranged one behind the other, the axes of the
one pair may either be arranged horizontally while those of the other pair are
arranged vertically, as shewn in Fig. 36 or the axes of both pairs may be horizontal
as at Fig. 37, in the first named case any rotation of the metal object is superfluous.
If as indicated by the arrows in Fig. 37, the one pair of rolls A B is made to
operate during the backward motion of the metal object while the other pair A' B'
is made to act during the forward motion thereof, the movement of the metal object
may be effected entirely by the rolls so that the metal object will be moved to and
fro thereby. The rotation of the rolls must, in this case, be so regulated that the
one pair of rolls frees the metal object as soon as the other pair begins to act.
For effecting the step by step forward motion with periodical retrogression, the
forward motion of the metal object is made somewhat greater than the backward
motion.
It is to be understood that with the rolling mill Fig. 37 on every change of motion
rotation of the metal object must be effected if it is of a circular or polygonal cross
section in a similar manner to ordinary rolling mills; the rolls of the above described
construction may be provided with several calibres formed in it side by side in
which the rolling operation may be carried out either simultaneously or consecutively.
In this case it is advantageous to arrange the working portion (Fig. 15) of one
calibre in line with the gap a (Fig. 15) and the contiguous calibre so that one rod
is being acted upon while the contiguous rod is being moved backwards during the
rest. In order that the metal object may be of equal thickness at all points of its
longitudinal axis, it is necessary that at the end of each rolling action the distance
apart of the roll axes s all be equal, or that the return movements shall always be
equal. If however during the rolling such distance be gradually altered which may
for instance be effected by turning the screw spindles for adjusting the bearings of
the upper roll, the metal object will be formed conical or conoidal or pyramidal.
This actuation of the screw spindles or of their gearing may be easily effected by a
ratchet motion that is actuated by one of the rolls or otherwise.
With an equal
adjustment for each rotation of their rolls the configuration of the metal object will
become conical or, in the case of a polygonal cross-section, similar to the frustrum
of a pyramid. If on the other hand the amount of adjustment be altered for cach
revolution, the metal object will become conoidal or of curved configuration. If

page_text: the rolls are made to approach each other during the rolling, the back end of the
metal object will become thinner than the front end. The reverse effect will be
produced if the rolls are gradually moved apart. By combination of the two
methods a body will be produced that is thinner at the ends than in the middle, thus
for instance producing a form of equal resistance against transverse strain. There
will be no difficulty in effecting by suitable actuation of the adjusting screw spindles
of the rolls, any desired alteration in the cross-sections with reference to the
longitudinal axis of the body. The same process can also be employed in the to
and fro movements, but in this case similar results can be obtained by altering the
reverse motion as by altering the position of the rolls, or the two methods may be
employed in combination. This will readily be seen if it is considered that the
outer configuration of the metal object is governed by the final positions of the rolls
Fig. 28. If now the return motion of the rolls is so altered that in place of the
narrower part of the calibre, by degrees the larger part of is made to act towards
the end of each operation, upon the metal object, a gradual increase of the cross-
section in the direction of the length will result. In a similar manner a reduction
of the section may be produced by gradually causing smaller portions of the calibres
to act upon the metal object towards the end of each rolling process. The guiding
and movement of the metal object will have in most cases to be effected indepen-
dently of the rolls that act upon it. In working bodies of plate form or sheet
metal, however, the said step by step and retrograde motion may be effected by
the rolls alone if they are formed with concentric calibres and are moved as
indicated at Figs. 30 and 35. The small shiftings 11 and 13 Fig. 29 are in
that case dispensed with, and it is only necessary to cause the rolls to turn
somewhat more during the forward motion of the metal object than during
the return motion. If therefore by way of example the rolls are driven by
a reversing steam engine with toothed gear transmission, the reversal of the engine
is so arranged that the motor, for instance, turns each time 4 times in the forward
direction, but only 3 times in the backward direction. If the rolls are then pressed
with sufficient force against the metal object so as to move it forward or backward
by frictional contact no further device for moving the metal object will be required.
For guiding the same, the ordinary roll tables with plane surfaces or with guide
rollers will be sufficient. If on the other hand the metal object has to receive a
certain shifting motion for carrying out the above described process, such shifting
can be effected in a great variety of ways. In the process described with reference
to Figures 11 and 29 for example the forward motion of the metal object which is
required in order to bring it under the action of the rolls may be effected by means
of weights or by springs. A more reliable result, however, will be obtained if a
positive motion is imparted to the metal object, this being effected either by means
of pairs of feed rollers, either in front of or behind the rolls, or by gripping
apparatus. When using pairs of guide and feed rollers in front of or behind the
rolls the former have the necessary reverse motion imparted to them in such
manner that the desired step by step forward motion with retrogression of the
metal object is produced. The required rotation of the metal object can in this
case be simultaneously obtained by placing the guide rollers in oblique positions.
The rotation of the metal object during the rolling operation can also be effected
automatically by arranging the axis of the rolls somewhat obliquely relatively to
each other. The metal object can in that case be brought back without rotation
into the original position during the period of rest in order again to be rolled and
simultaneously turned. The guiding and feed of the metal object by means of
grippers is more complicated. Figures 38, 39 and 40 show such an arrangement in
side view, front view and plan. The metal object W to be operated upon has a
rectangular cross section and is seized on each side of the rolls A and B by means
of grippers M and N which are guided in the direction of motion of the metal
object by means of guides H fixed to the sides of the housings S. Each gripper
consists of a lower cheek d and upper cheek f. The lower cheeks d are provided
at each end with trunnions d¹ which slide in the guides H. The lower cheeks of

page_text: The rota-
both grippers M and N are connected together by means of rods P situated outside
the housings S so that a rigid frame is formed by the parts d and f. These lower
cheeks d constitute the support for the metal object W and the trunnions d' of the
cheeks of the gripper H are connected by links g with the levers g of the shaft g"
which is moved to and fro by the connecting rod h of the crank ¹ fixed to the
lower roll B. The upper cheek f is guided in the frame shaped guides fixed to
the lower cheek d. Figure 41, and is always pressed downwards by means of
springs c situated in d2 so that the metal object W is nipped between the two
cheeks d and by the action of the springs c, and is thus made to participate in the
to and fro motion of the grippers M and N. As shewn in Figure 7, however the
backward motion must be smaller than the forward motion of the metal object and
the cheeks and must consequently only move the metal object during a portion
of their backward motion, the action of the springs must therefore be partially
counteracted during the backward motion. This is effected by means of the cam
shaft which is carried by the trunnion and the guides and is provided with
cams Figure 41 which act upon rollers on the lower ends of rods f' connected
to the cheek f. By a rotation of the shaft in the direction of the arrow Figure 41
the upper cheek f is raised and the metal object is consequently freed.
tion of the shaft 7 of the gripper N is effected by means of the lever connected
to the shaft Figure 38, which lever is connected by links with an extension ³ of
the connecting rod h. By the varying positions of the connecting rod h, on the
rotation of the roll B, the lever 12 of the shaft will receive an unequal to and fro
motion as shewn in the diagram Figure 42, representing some of the principal
positions of the crank h¹. The cams are so proportioned that towards the end of
the backward motion, the upper check f of the gripper N will be raised and this
motion of the shaft of the gripper N is transferred by an arm Figure 39 rod 15
and arm Figure 40 to the shaft 1 of the gripper m, consequently the metal object
will be simultaneously released by both grippers, so that it will be carried back by
these only during a portion of their backward motion. This raising of the upper
cheek could also be effected by inclined planes p Figure 43, which are connected
adjustably to the guides H and on which the rollers f2 on the lower ends of the
rods frun towards the end of the backward motion of the grippers. Figures 44,
45 and 46 show in side view, front view and plan a rolling mill for rolling bodies
with circular cross section. In this case also the metal object W is seized and
guided on both sides of the rolls A and B mounted in housings s this being effected
by means of grippers m mounted rotatably in the cross bars Figure 46 connected
together by rods P. so as to form a rigid frame. The grippers M consist as shown
at Figures 47 and 48 of a frame m' carried by a hollow trunnion in which frame
slide two cheeks which are pressed against the metal object W by springs c and
are thus made to hold it with a certain force. The hollow trunnion of each
gripper m has connected to it a toothed pinion r, with which gears a toothed
pinions whose hollow trunnion is also mounted rotatably in the cross bar .
Within the hollow trunnion s¹ is a sleeve s² Figures 49 and 50 which slides upon
the rod u carried by the guides H when the cross bars t have a to and fro motion
imparted to them through the shaft g² reciprocating lever connecting links
connecting rod h, actuated by crank ¹ on the lower roll B. On the rod u Fig. 46
is formed a helical groove into which takes a feather on the sleeve 82 so that on
to and fro motion being imparted to s² the latter receives at the same time a partial
rotary motion. This rotation is transmitted to the hollow trunnion >' through the
ratchet wheel 3 fixed to and the pawl ** carried by the hollow trunnion s¹,
the rotary motion of the latter being transmitted by pinions and r to
the gripper m.
and
According as the rolling-mill is to operate as described with reference to Fig. 7
or with reference to Fig. 11, there will be effected during the backward or forward
motion of the metal object a simultaneous rotation of the latter whereas the pawl **
slides loose over the teeth of the ratchet wheel at a time when the metal object

page_text: is being operated upon by the rolls, and consequently no rotation round the longi-
tudinal axis is to be effected. The forward motion of the frame formed by the
cross bars and rods P and which holds the metal object by means of the
grippers m is in this case just as great as the backward motion.
In order that the step by step forward motion with retrogression of the metal
object can be effected, there must be provided means whereby the rolls A and B
in operating upon the metal object cause this to shift somewhat in the grippers
during the rolling operations. For enabling this to be done, the pressure of the
spring c which presses the cheeks n against the metal object must be correspondingly
controlled. The mechanism for the movement and guiding of the metal object can
be effected in various other ways. It will mostly be dependent upon the nature of
the metal object, and the described arrangements are therefore only intended to
serve as examples for carrying out the process.
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 :-
1. The process of forming or rolling metal bars, rods, wire, plates or sheets,
consisting in causing the metal, while passing through the rolls to partake of a
combined step by step forward and intermediate retrograde motion, whereby the
metal object is consecutively operated upon on limited portions of its length such
point of operation being made to advance in a longitudinal direction along the
metal object, substantially as described.
2. A process of forming or rolling metal bars, rods, wires, plates or sheets
wherein the metal object is subject to the action of gapped or separable rolls in
such manner that after a certain length of the metal object has been acted upon by
the rolls during its forward motion, it is liberated from them, whereupon it is drawn
back and again fed forward in order to cause the rolls to act upon a following
portion of its length, substantially as described.
3. A process of forming or rolling metal bars, rods, wire, plates, or sheets
wherein the metal object is subject to the action of gapped or separable rolls in
such manner that after a certain length of the metal object has been acted upon by
the rolls while it is moving in a backward direction, it is liberated from them
whereupon it is moved forward in order to be again acted upon by the rolls while
moving in a backward direction, such action taking place on a portion of the object
following that which was first acted upon, substantially as described.
4. A process of forming or rolling metal bars, rods, wire, plates or sheets
wherein the metal object is subject to the action of gapped or separable rolls having
a reciprocating motion, the metal object being first acted upon while these revolve
in one direction and after being then liberated thereby, the object is moved forward
to a certain extent in the same direction and is then again acted upon by the rolls
while rotating in the contrary direction, substantially as described.
5. In the process of forming or rolling metal bars, rods, wire, plates or sheets
referred to in the preceding claims, effecting the partial rotation of the metal object
upon its longitudinal axis when it is liberated by the rolls, substantially as
described.
6. In forming or rolling metal bodies having a variable cross section in the
direction of the length in the manner set forth in the first claim, causing the
distance between the rolls to be varied during the rolling operation, substantially
as described.
7. In forming or rolling metal bodies having a variable cross section in the
direction of the length, in the manner set forth in the first claim, causing the extent
of the backward motion of the rolls having tapering or eccentric grooves or calibres
to be varied in such manner that by degrees different portions of the groove or
calibre are made to act upon the metal article, substantially as described.
8. The construction of rolling mills for carrying out the rolling process referred

page_text: to in the first claim wherein the periodical action of the rolls upon the metal object
is obtained by the periodical approach and recession of the rolls substantially as
described.
9. Constructing rolling mills for carrying out the rolling process referred to in
the first claim, wherein the rolls are constructed with portions only of their
peripheries formed with projecting parts for operating on the metal and with
intervening gaps or recessed parts for enabling the metal object to be moved freely
forward or freely backward in the intervals between the operations.
10. In rolling mills the rolls of which are constructed as set forth in the
preceding claim, forming the projecting parts with concentric or tapering calibres
or with both combined substantially as described.
11. In rolling mills constructed as set forth in the preceding claims, the use of
apparatus for moving and guiding the metal object consisting of gripping instru-
ments arranged in front and in the rear of the rolls, which seize the metal object
and move it to and fro, the requisite step by step forward motion with intermediate
retrogression being obtained by causing the gripping jaws to release the metal
object periodically or by imparting by means of the rolls a movement to the metal
object relatively to the gripping jaws which hold it with elastic pressure, substan-
tially as described.
12. The combination of two or more pairs or groups of rolls such as are referred
to in the preceding claims, so arranged as to operate on the metal object either
simultaneously or alternately, substantially as described.
Dated this 1at day of December 1891
ABEL & IMRAY,
Agents for the Applicant.