Quick change apparatus for guide rollers

A means for quickly placing a roller set onto a supporting shaft is disclosed. Generally, a guide sleeve is mounted at one end of the shaft and formed whereby the upper surfaces of the sleeve provide an aligned continuation of the upper surface of the supporting shaft. The remaining portions of the sleeve surface taper inwardly away from the imaginary continuation of the shaft surface. Thus, the sleeve has a diameter somewhat less than the outer diameter of the supporting shaft and accordingly, less than the inner diameter of the roller set. This arrangement facilitates a slipping of the roller set onto the guide sleeve without a need for precisely aligning the roller set with respect to the guide sleeve. The configuration of the upper surfaces of the sleeve insures the proper alignment of the roller set with the supporting shaft. Once the roller set is placed onto the guide sleeve, it may then be easily slipped from the sleeve and onto the shaft.

BACKGROUND AND SUMMARY OF THE INVENTION 
The invention relates to a device for quickly exchanging guide rollers or 
guide roller sets on and off supporting shafts of a roll mill train. 
In the cold alignment of profiles on roller aligning machines, it is always 
desirable to exchange the guide rollers in as short a time period as 
possible. When preparing the roll mill train for a new profile, the 
rebuilding period of the aligning machine should under no circumstances 
exceed the time required for the operation of the roll mill train itself. 
Depending upon its design, a roller aligning machine is provided with 
between 7 and 11 supporting shafts. The guide rollers of each shaft are 
assembled by means of a flange bushing and locking nut to make up a roller 
set. A key spring connection serves as torsion safeguard between the shaft 
and flange bushing. To rearrange the roller aligning machine with a new 
profile, all roller sets must be withdrawn from their respective shafts 
and replaced with new roller sets. 
It is well known in the art to exchange the guide roller sets by means of a 
crane with the assistance of wire cables, pliers or similar devices. Due 
to the very high hoisting speed of rolling mill hangar cranes, cranes with 
extremely low hoisting speeds are used, which are specially installed for 
the purpose of changing guide rollers at the roller aligning machines. 
However, despite the favorable operating features of such cranes, the 
alignment of a roller set with the central axis of the supporting shaft to 
facilitate slipping the set onto the shaft is very time-consuming. This is 
especially true in view of the fact that the clearance between the 
supporting shaft and the flange bushing is in the order of a few tenths of 
a millimeter, and a roller set may weigh up to 7 tons. 
It is also known to utilize rail as well as freetraveling devices equipped 
with several horizontally disposed mandrels arranged opposite the 
supporting shafts. A mandrel of this device must be brought before a 
supporting shaft in exact alignment if a roller set is to be slipped from 
the supporting shaft onto the mandrel or vice versa. Due to the narrow 
clearances, this, too, is a very time-consuming procedure. Furthermore, 
the devices mentioned require a great deal of floor space and are 
expensive. Accordingly, their use is generally limited to new plants since 
there is usually not enought space in existing plants to include an 
additional roller exchange device. 
It is a primary objective of the present invention to provide a device of 
the crane type to quickly and easily exchange guide rollers in a roll mill 
train. The apparatus disclosed herein may be installed in already existing 
plants with a minimum space requirement. Generally, the present invention 
is characterized by a centering sleeve-like member mounted on a free 
frontal face of the support shaft and arranged and configured whereby the 
upper surface thereof for about 45.degree. on either side of the center 
vertical is an aligned continuation of the support shaft shell surface. 
The remaining surfaces of the member converge radially inwardly from the 
imaginary projection of the shaft shell surface. In this manner, the axial 
spread of the member approximately matches the breadth of the guide roller 
or guide roller set. The guide roller set may be easily slipped onto the 
centering sleeve by any hangar crane. Since the outer dimension of the 
sleeve member is reduced relative to the support shaft, it is not 
necessary to suspend the roller set from the crane either exactly 
horizontal or exactly aligned with the support shaft. After slipping the 
roller set onto the centering sleeve, the set is in exact alignment with 
the support shaft and can be easily pushed onto the latter. The 
time-consuming alignment of the roller set with the support shaft is thus 
eliminated. 
In accordance with another feature of the invention, the sleeve member may 
be equipped with a key spring aligned with the key spring of the support 
shaft. The key spring of the guide member is formed to be of a width equal 
to the key spring of the support shaft and includes lateral faces which 
converge in the radial direction. When mounting the guide rollers or the 
guide roller set, the conicity of the sleeve key spring provides 
sufficient clearance to slip the roller set easily onto the support shaft. 
Slipping the roller set onto the support shaft or, in reverse, the 
withdrawal of the set from the support, may be done in a variety of ways. 
For example, light roller sets may be changed by hand, while heavier ones 
can be lifted by means of hydraulic or mechanical devices incorporated in 
the aligning machine, or by the crane itself.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION 
Referring now to the drawings, the reference numeral 1 represents a support 
shaft of a conventional roller aligning machine (not shown). The guide 
roller is preassembled on a flange bushing 7 and secured against axial 
displacement by means of a nut 3. The roller set 2, 3, 7 is slipped onto 
the support shaft 1 and secured against axial displacement by a ring 
member 8. 
To prevent relative rotation between the roller set 2, 3, 7 and support 
shaft 1, a key spring 5 on the shaft 1 is fitted into a key 6 arranged 
along the inner circumference of the flange bushing. 
In accordance with the invention, a guide sleeve 11 is mounted on a front 
face 9 of the support shaft 1. To precisely align the guide 11 with the 
axis of the shaft 1, the front face 9 is provided with a centering 
shoulder 10. Referring now to FIG. 3, the upper portion of the shell 
surface of the sleeve 11 is arranged as an aligned continuation of the 
surface of the shaft 1. The remaining portions of the sleeve 11 converge 
radially inwardly whereby its circumference is recessed from the 
circumference defined by the projected configuration of the shaft surface, 
indicated by the dotted line 15. A key spring 12 is arranged in the guide 
sleeve 11 and has a width equal to that of the key spring 5 mounted in a 
key 4 of the support shaft 1. The spring 12 matches the width of the 
spring 5 of the support shaft 1 only in the lower portions thereof. The 
lateral faces 14 of the spring 12 converge toward one another and the 
sleeve 11 is mounted whereby the springs 5 and 12 are axially aligned. 
To install the guide roller set 2, 3, 7 it is only necessary to slip the 
set onto guide 11 by means of a crane. This is a rather straightforward 
operation inasmuch as the outer diameter of the sleeve 11 is much smaller 
than the inner diameter of the guide roller set 2, 3, 7. The design of the 
guide 11 in the upper area is such that the roller set aligns itself 
automatically with the shell surface of the shaft 1, while the alignment 
of springs 5, 12 insure that the key 6 of the roller set is properly 
positioned with respect to the spring 5. The tapered surfaces 14 of the 
spring 12 also facilitate the installation of the roller set onto the 
support shaft.