EP0427156B1 - Skiving machine - Google Patents

Description

The invention relates to a sharpening machine with a feed roller with at least one guide element and with a bell knife for transporting and guiding flap-like workpieces made of leather or leather substitutes, and for making marginal cuts of a predetermined cross-sectional shape, with servomotors for adjusting the feed roller and the guide element, with an electronic control device which contains a memory for storing sets of setting values corresponding to cross-sectional shapes for the setting of the servo motors, and with a keyboard for addressing memory locations of the memory.

A sharpening machine of the type mentioned above is known from DE-OS 37 32 059.

Sharpening machines are used in the leather-working industry, in particular the shoe industry and the bagging industry, to provide cuts of leather, rubber, plastic or other leather substitutes on their edges by trimming with a predetermined cross-sectional shape. Cross-sectional shapes have developed certain standard shapes, which are referred to in technical terms as "cuts". Examples of such cuts with defined cross-sectional shapes are the so-called "undercut", the "buggy cut", the "front grill cut", the "open edge" and the "running edge", where other terms are also sometimes used for such cuts.

The cuts mentioned generally have either a bevel in the region of the edge of the workpiece or a recess with those parallel to the side surfaces of the workpiece Pages on. To define a particular cut of a type of cut, two values are usually sufficient, for example the remaining thickness at the trimmed front edge of the workpiece and the width of the cut at the surface plane of the workpiece or - in the case of an obliquely cut workpiece - the slope angle of the bevel.

In general, the blanks are provided with different types of cuts on their usually odd outer edges, depending on how the blank is to be assembled later with other blanks into an article, for example a shoe, a wallet or the like.

In so-called multi-cut sharpening machines, it is known to specify the intended cuts for each workpiece to be machined with their respective set of values, that is to say the two numerical values mentioned, one after the other in the form of a group of sets of values (cutting sequence), namely in the sequence as the cuts follow each other on the outer circumference of the workpiece. By means of a switch, usually a foot switch, the sets of values can then be called up one after the other, whereby the guiding elements and the feed roller are adjusted depending on the sets of values so that the sharpening machine performs the desired cut. In this way, the user of such a multi-cut sharpening machine can apply the workpiece to the sharpening machine at a predetermined starting position of the circumference and, with the first set of values set, carry out the corresponding cut over a specific circumferential range. He then switches over to the next set of values in the group by actuating the foot switch, and the sharpening machine adjusts its elements in such a way that the adjacent one is still unprocessed section of the circumference of the workpiece is further processed with the second preselected cut. However, it is usually the case that within a group of sets of values (cutting sequences) certain sets of values (cuts) recur periodically, because the way a cut is attached to other cuts, for example, is the same in pairs on the sides.

In the known sharpening machine mentioned at the outset, a monitor is provided, on the screen of which the cut selected in each case is shown both graphically and alphanumerically with its respective values. In addition, an article number, a sequence of cuts u. Like. Be displayed on the screen.

In the known sharpening machine, the values or sets of values are sorted according to article numbers, so that when an article number is entered, for example a model number of a shoe model, the corresponding values or sets of values are automatically called up.

As already mentioned, the individual cuts are defined by their values (thickness, width, angle) being specified. However, this means that the specified setting values must always refer to a certain initial thickness of the blanks supplied.

In the known sharpening machine, a weighting stage is therefore provided within the control unit, which is connected downstream of the memory. Depending on whether the blanks are made of thinner or thicker material, the cut decreases or increases Weighting level the setting values on their way from the memory to the control elements of the servo motors. In this way, the measured values used in each case are corrected in the required manner without the values in the memory itself being touched.

The known machine assumes that the user of the sharpening machine can feel the thickness of the material of the blank based on his many years of experience, in order then to set a corresponding correction factor if necessary via the weighting level.

The known sharpening machine therefore has the disadvantage that an exact correction of the cutting values, especially in the case of strongly fluctuating material thickness, is not possible or only takes a great deal of time, and it has been shown in practice that the users of such sharpening machines always carry out a number of test sharpenings carry out on workpieces before the optimal setting has been found again with changed material thickness. It is on the edge that this takes a considerable amount of time, apart from the fact that workpieces are spoiled by the test cuts and cannot be used.

In other known sharpening machines, which also have a memory for cutting values, the memory is essentially freely programmable and can therefore be programmed by the user of the sharpening machine according to his individual needs. In a known sharpening machine of this type, the memory contains, for example, 99 storage places, on which individual cuts or cutting sequences can be stored as values.

However, these known sharpening machines have the disadvantage that it is extremely difficult for a user to find the cut or cutting sequence required for the respective application, because experience has shown that the memory is arranged unsystematically when programming freely. In practice, therefore, users of such sharpening machines make use of more or less usable memo notes or brochures in which the individual cuts or cutting sequences are written down, so that they can be found by looking up if necessary.

The invention is based on the object to further develop a sharpening machine of the type mentioned in such a way that even in the case of workpieces with a fluctuating material thickness, the required cut or the required cutting sequence can be set without trying and without tedious searching in documents.

The object on which the invention is based is achieved in that a measuring device has means for detecting a thickness of the workpiece comprises that the measuring device generates a digital signal corresponding to the thickness, and that the measuring device is connected to a first address line of the memory.

The object underlying the invention is completely achieved in this way.

First of all, an exact digital measurement of the thickness of the workpiece guarantees that inaccuracies, such as those experienced by experienced workers when scanning workpieces, are completely avoided. Above all, however, the direct coupling of the thickness measurement with the addressing of the memory has the advantage that the memory location or group of memory locations in which those cuts or cutting sequences whose values are matched to the respectively measured material thickness are stored without error.

In this way, a time-consuming and tedious search in documents to find the required storage space is eliminated, because the assignment of measured value and storage space takes place automatically and thus practically without loss of time and without errors. Because the correct memory location is addressed automatically, trial cuts are also eliminated, and therefore neither material nor time is wasted.

Sharpening machines of the type of interest here are often used in larger production plants, where a large number of such machines with corresponding workplaces are accommodated in a common operating hall. If at Knurling machines of known type new batches of workpieces are delivered and it turns out that the delivered new workpieces are of different thickness, so there is considerable unrest in conventional production systems because now on each individual sharpening machine by trying or looking up measured values, a new setting of the Sharpening machine must be found. This concern naturally multiplies in larger production plants and can lead to a significant reduction in productivity.

In contrast, it has been shown in practical tests that considerable savings in time and material can be achieved with sharpening machines of the type according to the invention and that the disturbances in the operational sequence explained above are completely avoided.

In a preferred embodiment of the sharpening machine according to the invention, the first address line leads to at least one higher position of multi-digit addresses in the memory and a second address line which can be controlled manually by the keyboard leads to at least one lower position of the addresses.

These measures have the advantage that not only a single cut or sequence of cuts can be controlled via the thickness measurement, but rather a plurality of cuts or sequence of cuts in a second control level, all of which are designed for material of the measured cut thickness. The advantage for the user of the machine is that he only has to remember a certain small amount of cuts or cutting sequences, for example by consecutive numbers from 1 to 10, and that he uses this small amount of cuts or cutting sequences with any material thickness can because. the machine has already selected the group of cuts or cutting sequences that are assigned to the respective material thickness and only the desired cut or the desired cutting sequence has to be selected manually within this group.

In a particularly preferred development of the sharpening machine according to the invention, the measuring device further comprises means for detecting a hardness of the workpiece, the measuring device generating a signal corresponding to the hardness and a superposition stage for the thickness signal and the hardness signal being provided which is connected to the first address line.

This measure has the advantage that processing errors are excluded, which could result from the fact that For example, a particularly soft leather is compressed to a smaller thickness during processing, so that it would be necessary to work with values that correspond to the thickness of the leather in the compressed state. Due to the described superimposition of the measured values of thickness and hardness, a compensation is created here, because, for example, in the case of a very soft material, the memory addressing is shifted in such a way that the thickness of the material, which is too small, is used as a basis for processing the soft material.

Finally, an embodiment of the sharpening machine according to the invention is particularly preferred in which the measuring device is arranged directly above the guide roller.

This measure has the advantage that the machining position and the measuring position are located almost at the same viewing angle, so that the user of the sharpening machine can carry out the measurement and machining in succession without having to turn or tilt their heads. In addition, it is advantageously possible in this way to carry out the measurement and processing at almost the same location, so that measurement errors due to the mismatch between the measurement location and the processing location are eliminated.

Further advantages result from the description and the attached drawing.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the combination indicated in each case, but also in other combinations or on their own without departing from the scope of the present invention.

Fig. 1

eine perspektivische Gesamtansicht eines Ausführungsbeispiels einer erf indungsgemäßen Schärfmaschine;

Fig. 2

in Seitenansicht, teilweise im Schnitt und vergrößert, ein erstes Ausführungsbeispiel einer Meßeinrichtung für eine Dickenmessung, wie sie bei der Schärfmaschine gemäß Fig. 1 verwendet werden kann;

Fig. 3

eine Variante der Meßeinrichtung gemäß Fig. 2, die eine Messung der Dicke und der Härte gestattet;

Fig. 4

ein äußerst schematisiertes Blockschaltbild einer Steuerung der Schärfmaschine gemäß Fig. 1 mit einer Meßeinrichtung gemäß Fig. 3;

Fig. 5

eine schematisierte Darstellung eines Speichers, wie er für die Schaltung gemäß Fig. 4 verwendet werden kann.

Exemplary embodiments of the invention are shown in the drawing and are explained in more detail in the following description. Show it:

Fig. 1

an overall perspective view of an embodiment of a sharpening machine according to the invention;

Fig. 2

in side view, partly in section and enlarged, a first embodiment of a measuring device for a thickness measurement, as can be used in the sharpening machine according to FIG. 1;

Fig. 3

a variant of the measuring device according to Figure 2, which allows a measurement of the thickness and hardness.

Fig. 4

an extremely schematic block diagram of a control of the sharpening machine according to FIG. 1 with a measuring device according to FIG. 3;

Fig. 5

a schematic representation of a memory as it can be used for the circuit of FIG. 4.

In FIG. 1, 10 designates a sharpening machine with a box-like housing 11. A bell knife 12 with a horizontal axis of rotation protrudes slightly above a surface of the housing 11. A stop 13, a guide roller 14 and a feed roller 15 are arranged on the bell knife 12 in a manner known per se. The drive motors and servo motors for the sake of clarity, the adjustment of the above-mentioned elements is not shown in FIG. 1, they are also known per se.

A vertical attachment 20 of the housing 11 is provided with adjusting means 21, for example for grinding the bell knife 12 and for dressing the grinding wheel or the like.

On the right edge of the attachment 20, a hinge 22 is arranged, the counterpart of which carries a monitor 23 with a screen 24. The hinge 22 can be rotated about a vertical axis 25.

A surface 30 of the housing 11 has a depression 31 in the region of the bell knife 12. At the front of the depression 31 there is a desk-like front part 32, which is provided with a corner cutout 33 in the right front corner of the housing 11. A vertical axis 34 is arranged in the area of the corner cutout 33, around which a keyboard block 35 can be rotated in the direction of an arrow 36. The keypad 35 houses a keyboard 37 with a plurality of setting keys.

With 38 a foot switch is designated, which also serves to control a sharpening machine 10.

If the setting values for the sharpening machine 10 are predefined, as will be explained further below, the user can now insert a blank into the depression 31 in a manner known per se and can use the rotating feed roller 15 past the stop 13 and the guide roller 14, while the bell knife 12 processes the edge of the blank with the desired cutting shape.

When the circumferential section that should be machined with this particular cut shape is machined, the user of the sharpening machine 10 presses the foot switch 38 and the electronic control of the sharpening machine 10 automatically switches to the next set of values, the next cut to be made, within a cutting sequence corresponds. The stop 13, the guide roller 14 and the feed roller 15 are adjusted accordingly, and the user can carry out the cut now set over the next section of the circumference of the blank.

Both during the setting of the value sets as well as when processing the value sets during the processing of parts, the entered or the set value sets are displayed on the screen 24 alphanumerically and graphically, so that a constant control of the activity of the user of the sharpening machine 10 is possible.

As already mentioned above, the value sets, ie the numerical values for a certain type of cut, naturally depend on the thickness of the material of the blank. In order to allow a clear and reproducible selection of the correct values, a measuring device 40 is provided on the sharpening machine 10. The measuring device 40 is located on the vertical attachment 20, preferably directly above the guide roller 14.

As will be explained further below with reference to FIGS. 2 and 3, the measuring device 40 is used to measure the thickness of the material of the blank or additionally its hardness.

The arrangement of the measuring device 40 above the guide roller 14 has the purpose of achieving the measurement and processing of the blank in positions as close as possible, so that both steps take place from the same point of view of the user. For this purpose, the user inserts the blank into a measuring gap of the measuring device 40, the measurement is carried out, and immediately thereafter the user can insert the blank with the same location on the guide roller 14 for subsequent processing.

The measured value determined by the measuring device 40 is displayed on the screen 24 of the monitor 23, as indicated by 41 in FIG. 1.

A first embodiment of a measuring device 40 is shown in FIG. 2. On a machine-fixed housing 50 there is a support 51 for a leather workpiece 52, i.e. a blank of the type explained above.

A vertical measuring rod 53 is guided axially in the housing 50. The measuring rod 53 runs into a measuring plate 54 at its lower end. A length sensor is arranged at the upper end of the measuring rod 53, as illustrated by a mark 55 on the measuring rod 53, an immediately adjacent scale 56 and a clamp 57 connected to it. It goes without saying that the elements 55 to 57 can represent any type of length sensor, i.e. inductive, capacitive, magnetic, optical or other length sensors of known design.

A handle is indicated at 58, which allows the measuring rod 53 to be raised in the direction of an arrow 59.

The measuring rod 53 is provided with an axially fixed flange 60 between the two bearings of the housing 50. A helical spring 61 surrounding the measuring rod 53 is located between the flange 60 and an upper counter surface 62 of the housing 50.

The measuring arrangement 40 can be calibrated in such a way that, in the absence of an workpiece 52, the measuring plate 54 rests directly on the support 51 and the elements 55 to 57 are adjusted to emit a zero signal.

When the measuring device 40 is in operation, the user lifts the measuring rod 53 upwards against the force of the spring 61 by means of the handle 58 and places the workpiece 52 between the support 51 and the measuring plate 54. If the handle 58 is now released, the measuring plate 54 sets on the workpiece 52. The force of the spring 61 is dimensioned extremely low so that no measurement errors occur due to compression of the workpiece 52. The respective measured value of the thickness of the workpiece 52 can now be determined by means of the elements 55 to 57 and taken off at the clamp 57 as an electrical signal, preferably as a digitized electrical signal.

Fig. 3 shows a variant with a measuring device 40 ', in which some parts correspond to those of the measuring device 40 according to FIG. 2. These parts are the same in Fig. 3 Provided reference numerals, but an apostrophe is added in each case.

The measuring device 40 'shown in FIG. 3 enables not only the thickness of the workpiece 52' but also to determine its hardness.

For this purpose, a cylinder 70 is arranged on the housing 50 ', in the cylinder bore 71 a piston 72 runs. The piston 72, which is axially attached to the measuring rod 53 ', defines in the cylinder bore 71 an upper, first chamber 73, to which a fluid line 74 leads from the outside. A pressure sensor 75 is connected into the fluid line 74, the signal of which can be removed at a terminal 76. The fluid line 74 can be pressurized or depressurized in a manner known per se by means of a 3/2 solenoid valve 77. For this purpose, the solenoid valve 77 can be actuated via a terminal 78 by means of a control signal. On the input side, the solenoid valve 77 can be connected to a pressure line 79 or a pressure-free reservoir 79a.

In a second chamber 80 of the cylinder bore 71 below the piston 72 there is the helical spring 61 ', which supports the piston 72 downwards against the cylinder 70 and thus the housing 50'. A line 81 leads from the second chamber 80 to an unpressurized reservoir 82.

The mode of operation of the measuring device 40 ′ according to FIG. 3 is as follows:
In the rest position, the solenoid valve 77 is in the position not shown in FIG. 3. The fluid line 74 is relaxed, and the spring 61 'presses the piston 72 and thus the measuring rod 53' upwards.

In this position, the workpiece 52 'between the support 51' and the lower end of the measuring rod 53 'can be placed. The solenoid valve 77 is now switched to the position shown in FIG. 3 by applying a corresponding control signal to the terminal 78. In this way, the fluid line 74 is connected to the pressure line 79, and it builds up a pressure within the first chamber 73, which presses the piston 72 against the force of the spring 61 'down. Again, the force of the spring 61 'is set as low as possible to avoid measurement errors.

During the lowering of the piston 72 and the measuring rod 53 ', the vertical position of the measuring rod 53' and the respective pressure in the first chamber 73 are measured on the elements 55 'to 57'.

This pressure initially takes a very low value, which only has to overpress the force of the spring 61 '.

Now sets the measuring rod 53 'on the workpiece 52', the pressure in the first chamber 73 suddenly increases, with the result that the thickness of the workpiece 52 'can be measured by linking the signals at the terminals 57' and 76 ' .

If the pressure in the first chamber 73 continues to rise, a force-path diagram can now be recorded by firstly the path of the measuring rod 53 'in the manner already described and secondly the force via the pressure signal (terminal 76) and the cross-sectional area of the piston 72 is determined. From the force t-path diagram, the slope of the measurement curve and thus the elasticity or hardness of the workpiece 52 'can be determined in a manner known per se.

The measured values determined with the measuring devices 40 and 40 'of FIGS. 2 and 3 are now displayed on the one hand directly as digital values on the screen 24 of the monitor 23, but on the other hand they also serve for internal control of the sharpening machine 10, as will be explained below becomes:
4 shows an extremely schematic block diagram of the control of the sharpening machine 10.

This controller contains a memory 90 which, on the one hand, can be manually addressed in a conventional manner via a terminal 91, namely via the keyboard 37 of the keyboard block 35.

A connecting line 92 of the memory 90 leads to an electronic control unit 93, to which control signals can also be fed manually via terminals 94 and 95. The control unit 93 in turn controls servomotors 96, 97 etc. in a manner known per se for adjusting the feed roller 15 and the guide element 13, 14.

The previously conventional control system is now supplemented by the fact that a partially automatic addressing of the memory locations of the memory 90 is provided.

For this purpose, the thickness signal, which was measured by means of elements 55 to 57, is passed directly to memory 90 via a first address line 99a, while those that can be input manually Addressing signals from the terminal 91 are supplied to the memory 90 in the manner already mentioned via a second addressing line 99b.

In one embodiment of the invention, the thickness signal can be superimposed in a summing point 98 with the hardness signal, which is supplied by the pressure sensor 75.

To explain the mode of operation of the elements mentioned above, reference is first made to the detailed illustration of the memory 90 in FIG. 5:
It can be seen there that the memory 90 has, for example, a total of 300 memory locations 101, each of which can be addressed by an address 100. The addresses 100 have three digits, with a first address digit being 100/1, a second address digit 100/2 and a third address digit 100/3. The memory locations 101 themselves are divided into 10 positions 101/1, 101/2 etc.

In this way it is possible to identify each of the 300 memory locations 101 with a decimal three-digit address 100. A maximum of ten cuts can be stored in each storage location 101. The cuts are symbolized below with A, B, C, D, E, these letters denoting the usual cuts, namely, for example, a step, a bow cut, a front grill cut, an open edge or a running edge.

As can be seen from the illustration in FIG. 5, the addresses 100 begin with the numbering "020" in the first line, and only a single section A is stored in the associated first storage location 101. In the next line with the address "021" there is a single cut B, in the following "022" a cut C, in the following "023" a cut D and in the next "024" a cut E.

In the following line "025" the cutting sequence A-B is stored, and this continues with cutting sequences B-C, then C-A, then A-B-C-B-A-B-C-B-A and then A-B-C-A-B-C-A-B-C.

In this way, a total of thirty groups 102 of ten memory locations 101 are formed in the memory 90. Within each group 102, the sequence of cuts (in the first five storage locations) or cutting sequences (in the second five storage locations) is the same.

The addressing is the same in the first two digits within each group 102, while the addressing in the third digit is numbered from 0 to 9. The addressing in the first two digits is identical to the section thickness, measured in tenths of a millimeter. Addressing "025" therefore means that the corresponding memory location is designed for u a material thickness of 0.2 millimeters and contains the cutting sequence A-B (for this material thickness). Correspondingly, the addressing "315" means that the storage location 101 is designed for a material thickness of 3.1 millimeters and also contains the cutting sequence A-B.

If one now considers the representations of FIGS. 4 and 5 together, the result is that the first address line 99a is assigned to the first two digits 100/1 and 100/2 of the addresses 100 while the second address line 99b is switched to the third position 100/3 of the addresses 100.

If, for example, a thickness of 0.2 millimeters is measured on the workpiece 52 by means of the measuring device 40 according to FIG. 2, this value appears at the terminal 57, for example as a digital value, or it is converted from an analog value into a digital value. This digital value is now transferred to the memory 90 via the first address line 99a, with the result that the first group 102 is selected there directly, because only there the two first digits 100/1 and 100/2 have the values "0" and " 2 ", corresponding to 0.2 millimeters in thickness.

The user of the sharpening machine 10 now only needs to use the keyboard 37, i.e. in FIG. 4, the terminal 91 to specify a decimal value varying between 0 and 9 in order to select one of the ten possible cuts or cutting sequences. The user does not need to read, process or take the measured value of the thickness into account in any other way, because the corresponding selection is made automatically, as explained. Overall, the user of the sharpening machine 10 therefore only needs to remember ten cuts or cutting sequences or to write them down on a slip of paper, the machine 10 making its selection not only from ten, but rather from three hundred memory locations 100.

If, in addition to the thickness, the hardness of the material of the workpiece 52 'is detected, as is possible with the measuring device 40' of FIG. 3, the measured value of the hardness in the summing point 98 is superimposed on the measured value of the thickness. This can done easily by subtraction. If, for example, the measuring device 40 'determines that the material of the workpiece 52' is relatively soft, a thickness value, for example, measured of 0.4 millimeters at the summing point 98 is converted into a value of 0.3, and with the number sequence "03" then the first two digits 100/1 and 100/2 of the addresses 100 are applied. The sharpening machine 10 then operates as if instead of the soft workpiece 52 'of 0.4 millimeters in thickness, a harder workpiece of 0.3 millimeters in thickness was processed. The compression occurring when machining the soft workpiece 52 'is compensated in this way.

It has already been mentioned that the letters A, B, C, D and E in Fig. 5 symbolize the usual cuts of the sharpening technique. Each letter is assigned one or two numerical values that determine the geometry of the respective cut. It goes without saying that the letters mentioned correspond to the same numerical values only within each group 102, while the letters in different groups naturally embody different numerical values because these numerical values vary with the thickness of the workpiece.

The determination of these numerical values or, in other words, the matrix of the values within the storage locations 100, is determined empirically, with subjective considerations of the individual users of the sharpening machine 10 also being incorporated. For example, one and the same cut can be defined differently for a certain thickness in its special values. This different definition of the values then leads to a different appearance of the finished article manufactured seams or butt edges. It may therefore be desirable from a fashion point of view to give the fundamentally known cuts a certain character by selecting certain associated values.

When the sharpening machine 10 is manufactured, a matrix of values can therefore be stored in the memory 90 merely by way of example, which matrix can then be varied accordingly by the respective end user. It is possible to proceed with known methods of characteristic variation by defining individual, unchangeable measured values as the base points of a characteristic field and converting a standard characteristic field specified by the manufacturer of the sharpening machine 10 into a desired new characteristic field using a known mapping method. The consequence of this is that the basic laws of the map are retained, but the individual values of the map are adapted to the desired special features of the user of the sharpening machine 10.

Claims (4)

1. Scarfing machine having a feed roller (15), with at least one guide element (13, 14) and with a bell cutter (12) for transporting and guiding rag-like workpieces (52) of leather or leather substitutes, and for making cuts of predetermined cross-sectional shape at the edges, with servo motors (96, 97) for displacing the feed roller (15) and the guide element (13, 14), with an electronic control apparatus (40) which comprises a memory (90) for storing sets of setting values corresponding to cross-sectional shapes for setting the servo motors (96, 97), and with a keyboard (37) for addressing memory locations (101) in the memory (90), characterized in that a measuring device (40) comprises means for determining a thickness of the workpiece (52); in that the measuring device (40) generates a digital signal corresponding to the thickness; and in that the measuring device (40) is connected to a first address bus (99a) of the memory (90).
2. Scarfing machine according to Claim 1, characterized in that the first address bus (99a) leads to at least one higher digit of multi-digit addresses (100) of the memory (90) and a second address bus (99b) which can be controlled manually from the keyboard (37) leads to at least one lower digit of the addresses (100).
3. Scarfing machine according to Claim 1 or 2, characterized in that the measuring device (40') further comprises means for determining a hardness of the workpiece (52); in that the measuring device (40') generates a signal corresponding to the hardness; and in that a superimposing stage (98) which is connected to the first address bus (99a) is provided for the thickness signal and the hardness signal.
4. Scarfing machine according to one or more of Claims 1 to 3, characterized in that the measuring device (40) is disposed directly above the guide roller (14).

Images