Method of profiling metal strips

In profiling the surface of a metal strip, particularly pressed strips for use in double band presses, the pressed strip is provided with graduations on a surface outside of the surface to be profiled. The graduations on the strip correspond to graduations on a tool used to profile the strip surface. With the graduations on both strip and tool in register, synchronized movements of the strip and the tool is effected with the strip being rolled into surface contact with the profiling surface of the tool so that the profiling surface of the tool is reproduced on the strip.

SUMMARY OF THE INVENTION 
The present invention is directed to a method of profiling a surface of 
metal strips, in particular, pressed strips for double band presses. 
Profiling workpiece surfaces, such as pressed strip surfaces, can be 
effected by stamping, removing or sloughing-off material of the workpiece 
for profiling its surface. Where the surface of the workpiece is 
sloughed-off the procedure is commonly referred to as the so-called 
cutting or chip-removing process. Such a metal working process includes 
chipping, planing, hammering, sawing, turning, milling, grinding, drilling 
and the like. 
Further, it is known to carry out the sloughing-off or removal of the 
material by electrothermal means, by spark erosion, or by electrochemical 
means. The electrothermal removal is performed in a stationary discharge 
process using an electric arc where the removal procedure is of a purely 
thermal nature. In spark or electroerosion, the removal is effected by 
spark erosion, however, the discharging process is not stationary, rather 
it is controlled through special energy sources which supply the spark gap 
with pulse-like bursts of energy. Furthermore, the electrodes can perform 
mechanical oscillation and rotational movements to assist in the removal 
work. By introducing a dielectric working fluid between the electrodes, 
the distance between them can be significantly reduced and the 
sloughing-off effect of the discharge can be substantially increased. 
Material removal by electrochemical means, otherwise referred to as 
electrochemical immersion, is carried out by inserting a cathode pole 
processing tool or a tool electrode with a constant feed speed into an 
anode pole workpiece or a workpiece electrode. A working slot is 
established between the workpiece and the tool as a result of this process 
with an electrolyte solution flowing at high speed through the slot for 
carrying off the removed material and also for removing the heat generated 
by the flow of current. Finally, profiling of the surface can be achieved 
by stamping rolls or grooved rolls. The grooved roll processing is 
performed by pressing the profiled surface of a grooved roll against the 
surface to be profiled. 
There are a number of methods and devices for the electro-erosion or 
electrochemical processing of workpieces and also for processing 
workpieces using a stamping procedure with the workpieces being of a 
number of different kinds. To-date, however, these various processes have 
not been used on metal strips or pressed strips, since there has been a 
technical prejudice against using these well known processes for profiling 
metal strips and, in particular, pressed strips. Furthermore, there has 
been difficulty in adapting the geometrically indefinite form of the outer 
surface of the pressed strip and its dimensions to the processing tools so 
that a satisfactory surface texture without projections could be produced. 
With regard to the state of the art reference is made to German Pat. Nos. 
1 298 854; 1 440 999; 1 565 468 and 1 961 676; British Pat. Nos. 856 340 
and 885 793; French Pat. No. 1 224 109 and U.S. Pat. Nos. 3,042,789 and 
3,363,082. 
It is also known to shape or profile the outer surface of rolls for use in 
printing or stamping workpiece surfaces by the above-mentioned methods. In 
carrying out such a procedure, the circumference of the tool (or of the 
electrode employed in an electrothermal or electrochemical process) and 
the circumference of the roll to be profiled are dimensioned so that the 
pattern length can be accommodated by a whole number of times on the 
surface of the roll to be profiled. 
Therefore, the primary object of the present invention is to adapt the 
known state of the art used in pressing and stamping rolls in the 
profiling of pressed strips for double band presses with the strips having 
a length as distinguished from the rolls, which is several times the usual 
roll circumference and the length is such that it can be determined only 
at considerable expense. To further complicate matters, the length must be 
maintained or any change in length must be constantly measured and 
adjusted during the processing operation. 
In accordance with the present invention, the surface of the pressed strip 
outside the surface to be profiled, is provided with graduations arranged 
to register with corresponding graduations on the profiling tool or the 
graduations can be checked by electronic or mechanical means to provide a 
synchronization of the movement of the tool and the workpiece or strip for 
reproducing the surface profile of the tool on the strip through 
electrothermal, electrochemical or mechanical processing. The graduations 
on the strip surface correspond to a whole number multiple of the 
graduations on the profiling tool. The length of the graduations on the 
tool may be its full circumferential length or it may be a lesser 
dimension if the reference length on the tool is not for its full 
circumference. 
A forced synchronization between the outer surface of a driven guide drum 
supporting the pressed strip can be achieved, for example, by a 
gear-toothed system as disclosed in the German Offenlegungsschrift No. 2 
737 629. In this patent publication gear teeth extend along the side edges 
of steel strips and mesh with gear teeth on a corresponding hollow gear 
wheel on the guide drum. 
With this synchronization it can be assured that during the rolling of the 
strip an exact whole number of lengths equal to the toothed tool 
circumference can be formed on the pressed strip surface so that the 
beginning and end of the profiled surface merge into one another without 
any visible projections taking into account the possible presence of 
slippage. 
In carrying out this procedure, the pressed strip is stretched over two 
guide drums and driven by means of gear teeth on the edge. The tool or 
tool electrode engages or meshes at an appropriate location with the 
pressed strip stretched over the guide drums and is driven in a rolling 
manner. If both drive mechanisms are synchronized either mechanically by a 
known gear arrangement or electrically by well known position control 
systems, then the projection-free surface profiling of the pressed strip 
for double band presses is effective with a surface reproduction on the 
strip of the profiling surface on the tool down to the finest detail. 
The various features of novelty which characterize the invention are 
pointed out with particularity in the claims annexed to and forming a part 
of this disclosure. For a better understanding of the invention, its 
operating advantages and specific objects attained by its use, reference 
should be had to the accompanying drawings and descriptive matter in which 
there are illustrated and described preferred embodiments of the invention 
.

DETAIL DESCRIPTION OF THE INVENTION 
In the drawing a strip 2, the surface of which is to be profiled, is 
stretched over a drum 1 driven in the direction of the arrow 6. A tool or 
tool electrode 3 having a profiling surface 4 to be reproduced on the 
strip 2 is positioned relative to the drum 1 so that it can effect a 
rolling action similar to the drum with contact between the profiling 
surface 4 and the surface of the strip 2 occurring in a synchronization 
region 5 on both the strip 2 and the tool 3. The synchronization is 
achieved by providing graduations, not shown, on the strip outside of the 
surface to be profiled so that these graduations register with graduations 
on the tool or tool electrode so that synchronization of the movement of 
the tool and the strip can be achieved. 
While specific embodiments of the invention have been shown and described 
in detail to illustrate the application of the inventive principles, it 
will be understood that the invention may be embodied otherwise without 
departing from such principles.