DE10023210A1 - Positioning blades on device for cutting material strip, involves detecting distance from one edge to base marker, moving blade to achieve defined distance, disengaging displacement device - Google Patents

Abstract

The method involves moving a sensor (15) on a displacement device (8) past the blade (I-III) to be positioned to produce successive edge signals for the edges of the blade, identifying the sensor signals as cutting edge (6) and construction edge (19) signals, detecting the distance from one edge to a base marker, moving the blade to achieve a defined distance then disengaging the displacement device.

Description

At facilities for slitting a web of material other assigned upper knives and lower knives that coexist others are engaged in a corresponding measurement serwelle or on a corresponding lower cutter bar meh Other lower knives in the form of plate knives, cutting rings or the like. Such knives are either held and fixed on the knife shaft or but ver via separate knife holder on a knife bar arranged to slide and fix. Depending on the concept of Set up at least the cutting of the lower knife be reground from time to time. With so-called groove knives, which are mounted on a knife shaft, become Regrinding all lower knives removed from the knife shaft and postponed after grinding. With lower knives, which are arranged on knife holders, become the lower knives removed from the individual knife holders and after the Grind again connected to the knife holder that was in ner given position connected to the lower cutter bar remains. In both cases it is necessary to use the lower knife reposition, as the La the cutting edge has changed.

From DE-U-29 50 9893 is a positioning device for Un term meter known, which has a displacement device, one of which encompasses the lower knife over the outer circumference Gripping device for the lower knife to be moved and two optical lasers to detect the cutting edge are arranged. The lasers are slightly in the direction of displacement Distance of about 0.1 mm from each other to the positi on the cutting edge by a "positive" signal from one  Lasers and a "negative" signal from the other laser grasp. This arrangement is very complex and cannot a "cutting edge" from another edge to the individual To distinguish lower knives.

From EP-A-0 770 460 it is known to be positioned in each case Knife with a displacement device via a programmable te control device, the respective, first over an inductive sensor detected edge of the knife over a Register signal. Then the ge in the program stored width of the knife on the displacement device the given geometric center of the knife is shifted and then the driver means activated and the knife on the shifted from the control device predetermined new position ben. A correction regarding regrinding and resulting change in knife width is not possible because the position of the cutting edge is not detected.

From EP-A-0 976 509 it is known the actual position the cutting edge to a carrier via a first sensor capture and the position of the movable carrier opposite to detect a zero mark via a second sensor and these two values via a corresponding control device to link in one arithmetic operation. Then the Control device controlled. Such an arrangement is not only complex, but also includes a wide range Causes of measurement errors.

The invention now relates to a method for positioning of knives, in particular of lower knives on a device device for slitting a web of material that is referred to at the beginning neten type, the one with the respective Un to be positioned Term knife that can be brought into engagement via means of intervention, with egg ner measuring device related to a tax baren drive connected displacement device that according to the invention is characterized in that with the Ver  slide a sensor on the Un to be positioned the knife is moved past and thereby from the edges of the A signal is generated one after the other, that from the given assignment of the direction of movement Sensor for aligning the cutting edges of the bottom knife signals from the sensor as "cutting edge" and as "Construction edge" in the measuring device identified who that over the signal of one of the edges in the measurement direction is defined as a "measuring edge", preferably via the Signal of the "cutting edge", the actual distance of the "meas edge "to a base mark in the measuring device is detected (Actual distance) and then the lower knife to be positioned after engagement of the displacement device is moved until the specified distance of the "measuring edge" to the base mark (TARGET Distance) is reached and the intervention is released again.

A "measuring device" in the sense of the invention comprises a programmable electronic computer with data storage, associated with this means for controlling the drive the displacement device, furthermore means for detecting and Signaling of the displacement path to the computer and the Sensor for detecting the "edges" of the knives.

With the help of this method, with just one sensor, preferably a laser beam transceiver, in the front drive clearly identify the given "measuring edge". The number of the resulting from the construction of the knife Edges per knife that can be detected by the sensor can be program will be taken into account. So point out called slot knife or plate knife two edges while in so-called cutting rings due to the constructive Circumstances result in three edges, which when moving the measurement be detected along the knife.

Are the lower knives arranged so that all cutting edges defined as "measuring edges" each on the  Zero mark facing away from the lower knife are what is programmed in the memory of the measuring device, then from the measuring device via the sensor of each Lower knife detects two signals triggered by the edges. Due to the assignment described above, the "Si gnal 1 "by the edge and defined by the back surface the "signal 2" generated by the cutting edge. Here it is basically irrelevant at what distance the individual Lower knives are arranged to each other, if at least that required for operation, based on the direction of motion first lower knife with both edges from the sensor of the ver sliding device is detected. It is only necessary here agile that the direction of movement of the measuring device Shifting device during the acquisition process is viewed. If the acquisition process starts at the zero Brand, then with appropriate "programming" the electrical or electronic measuring device ben that only every second signal, that is by a Cutting edge of each lower knife triggered signal when "Measuring edge" is detected.

In so-called cutting rings, four are from the sensor Detectable edges are available, with each assignment to the movement direction the second edge or the third edge the cutting edge and thus expediently forms the "measuring edge".

The movement of the displacement device takes place from that of the Zero mark away from the end, then inevitably results fig for the measuring device that the "signal 1" each "Measuring edge" represents and accordingly the "signal 2" single Lich in the sequence of signals to identify the next cutting edge is taken into account. After on this way depending on the measuring device for a lower knife because the actual distance of the cutting edge to the zero mark is recorded is, the displacement device can via the measuring device be controlled accordingly, so that from the shift  device after intervention of a corresponding intervention with the lower knife is moved until the cutting edge is set at the TARGET distance.

As a sub due to the successive signals knife is defined, can also be from the respective Ab follow the signals the lower knife to be moved identify, so that pre in the measuring device given number of lower knives with their associated TARGET-Ab of the cutting edges one after the other each bottom knife po can be sitioned.

Because the width of the lower knife and thus the assignment of the Edges to each other, of slight dimensional deviations after the Apart from grinding the cutting edge, known as the basic dimension is, the lower knife can be at any distance from each other be arranged on the lower knife shaft. If "right" Each bottom knife from the signal sequence "1" and "2" for slot or plate knives and from the signal sequence "1", "2", "3" and "4" identifiable for cutting rings. At Cutting rings must then the direction of movement for the Identi The "cutting edge" must be taken into account. Yes after The cutting edge is moved by the signal "2" or the signal "3" identified.

For lower knives that can be moved on a lower knife shaft after grinding, the individual sub knife pushed onto the lower knife shaft, the one individual bottom knives with bottom knives accessible from outside provisionally by hand approximately to the specified position can be advanced. About the slider is then ever using the program of the control device because the lower knife is pre-selected by the cutting program ver given and defined by the cutting edge pushed. The necessary displacement routes result in essentially from the opposed by the hands-free postponement  actual and detected by the sensor of the displacement device Position.

For lower knives that are attached to knife holders, lead ben the knife holder in the by the cutting program given setting, so that the reground water are first connected to the knife holders and then through the sensor of the measuring device the regrinding changed the actual position of the cutting edge summarizes and the knife holder overall over a corresponding engaging means acting on the knife holder as far as possible is pushed that the TARGET position of the cutting edge again is reached.

The above detailed explanation leaves the special Recognize the advantage of the method according to the invention. It will only one sensor is required, which is attached to the displacement device is ordered. The "intelligence" required is total assigned to the programmable control device. Because in the Control device via programming not only the ever because the desired position of the knife can be specified, but also the characteristic constructive data of the use ten knives can always be taken into account is always an Er the most important position, namely the position of the "Cutting edge" immediately possible. So that's one too the cutting edge related positioning of the respective measurement possible.

The method according to the invention not only allows the exact Positioning of the knives with a new adjustment or for Correction of regrinding or wear, but also an adjustment during operation with slowly tepid fender material web when changing the cutting program. For this it is then necessary, also for the upper knife To provide shifting device that is synchronized with the movement  the moving a lower knife moving device becomes.

Since with the help of a laser beam the respective position of the "Measuring edge", preferably the "cutting edge", to be moved the lower knife with the help of a corresponding measuring device direction on the shifter very precisely who that can, it is useful in one embodiment of the invention moderate, for the lower knife to be positioned at the Festle the displacement distance between the actual distance and the target down stood the geometric conditions of engagement between Ver sliding device and lower knife to be positioned in the Measuring device to be considered. This procedure he it allows the displacement device with engagement means, for example in the form of slidable or pivotable with fingers, to be provided, depending on the shape either on the system defined by the cutting edge surface and / or on the one defined by the back edge Contact surface, but also form-fitting on the peripheral surface or frictionally, can be applied. No one is required here complicated means of precision intervention, but it is le diglich necessary that the distance between the contact surface of the engagement means and the sensor in the measuring device is specified. This distance can be a few millimes ter amount, so that there is always sufficient space between the means of engagement and the relevant contact surface at the Un is guaranteed. The one stuck in the measuring device predetermined distance Δa between the contact surface at the on gripping means and the sensor can then be used when determining the from the detection of the actual distance to the shift to TARGET distance specified dimensions are taken into account. The Intervention means can be designed so that it either on the one defined by the cutting edge Engagement surface as well as on the defi through the back surface the engaging surface can be created. About the direction of movement device of the shifting device for shifting the lower part  An exact position can always be set to the TARGET distance the cutting edge to its desired distance digits.

Since the sensor is fixed to the ver with a controllable drive see shifting device is connected, which in turn communicates with the computer and their position Computer signals, there is also the possibility during of the company to check the knives for wear. The displacement device is then only along the measurement serbalkens or the lower knife shaft, the on Gripping means remains inactivated, and this becomes the ACTUAL dimensions of the cutting edges with those saved in the computer TARGET dimensions compared. This can cause wear and tear Keeping a tolerance zone continuously monitored and the quality control will be improved.

In a particularly advantageous embodiment of the method provided that after the detection of the signal "Kon structure edge "of the drive of the displacement device "Creep speed" switched and via the signal "Cutting channel te "is switched off. This is an exact positioning the shifting device when the "measuring channel." te "also possible with only one sensor, in particular a laser Lich.

In one embodiment of the method according to the invention further provided that by a measuring run the displacement Direction across the entire width of the facility in front of the Po sitioning of the individual lower knives the number of in the ar and the position of the lower knife Base mark on the signals emitted by the sensor in the Measuring device is detected and that then the individual Lower knife to be repositioned according to the specifications of the Editing programs to their TARGET distance to the base brand posi be tioned. Since, as already described above, the  Alignment of the cutting edges of the individual lower knives in with regard to the zero mark are generally known and for the direction of movement can be specified for the measuring run, for example in a direction that is so for a slot knife is specified that the "signal 1" by the Back surface shows defined edge and the "Signal 2" the indicates the edge defined by the cutting edge, can be used to one from the number of the sequence of "signal 1" and "Signal 2" not only the number of the work area Chen lower knife, but also the distance their cutting edge to the zero mark.

After recording this actual state with regard to all submeasures Water in the work area can then shift the individual lower knife to the new cutting program the. Here, in the given programming of the new Cutting program for the individual lower knife shifts made with the least possible displacement and in their new TARGET distance. Because the number and the assignability of the individual lower knives in relation to the Given this zero mark, this procedure also allows for a change of the cutting program surplus lower knives push out of the work area or additional ones Lower knife from a "storage area", which is usually in a storage space in the area of the zero mark is given, additional Lich introduce.

The invention is based on schematic drawings of a Embodiment explained in more detail. Show it:

Fig. 1 a displaceable cutting means having on a lower knife shaft and gatherable lower blades,

Fig. 2 shows an enlarged view of the process sequence for the displacement of a lower knife.

Fig. 3 is a plate diameter,

Fig. 4 shows a cutting ring.

The device shown schematically in FIG. 1 for longitudinally dividing a material web has a cutter bar 1 on which a plurality of cutter holders 2 can be moved and fixed, on which upper cutters A, B and C are arranged. The knife holder 2 are designed in a conventional manner so that the upper knife connected to them from the rest position shown by lowering in the direction of arrow 3 and moving via an adjusting means 2.1 on the knife holder 2 in the direction of arrow 4 with its cutting edge 5 on the cutting edge 6 one assigned lower knife I, II, III are brought into the cutting position, as shown for the upper knife A and the lower knife I. In the illustrative example, the lower knives I, II, III are arranged in the form of groove knives on a lower knife shaft 7 and can be moved and fixed. The lower knife shaft 7 is connected to a rotary drive, not shown here, so that, in the cutting position shown for the lower knife I, the material web passing through between the upper knives and the lower knives is supported by the lower knives.

The lower cutters are assigned a displacement device 8 , which can be moved on a measuring bar 9 by means of a drive drive, not shown here. The Verschiebein direction 8 is provided with a measuring bar 9 assigned to position sensor 10 , which is connected via a connection, which is only schematically indicated, to a preferably electronic, programmable computer 12 provided with a data memory. About the connection 11 can not only be detected with the help of the computer 12, the respective position of the displacement device 8 on the measuring bar 9 , but also the travel drive can be controlled so that any predetermined position of the displacement device 8 on the measuring bar 9 can be approached.

The displacement device 8 is provided with a here only schematically represented, controllable via the computer 12 a grip means 13 , which will be described in more detail below in its function. A zero mark 14 is assigned to the measuring bar 9 , so that the distance l ₁ , l ₂ , l ₃ to the zero mark 14 results for the cutting edges 6 of the individual lower knives I, II, II.

The displacement device 8 has a sensor 15 , which is designed, for example, as a laser beam transmitter-receiver, the beam of which is oriented in the direction of arrow 16 perpendicular to the lower knife shaft 7 , with a reflection from the peripheral surface 17 of a lower knife or the absence of a reflection from Sensor 15 is detected as a signal. The resulting signals are forwarded to the computer 12 in connection with the distance signal output by the position transmitter 10 to the computer 12 .

If the displacement device 8 is now moved past the lower knives I, II and III from the zero mark 14 , the result is, when the sensor is designed appropriately, for example with corresponding signal formation, a first signal when the beam 16 strikes the back surface che 18 of the respective lower knife defined construction edge 19 and a second signal when reaching the cutting edge 6 .

Now, taking into account the direction of movement of the displacement device in the direction of arrow 20, the "signal 1" emanating from the edge 19 as the signal of the construction edge 19 and the "signal 2" thereafter proceeding from the cutting edge 6 as the cutting edge, then in compute ner 12 from the sequence of "signal 1" and "signal 2" not only detect the position of a cutting edge 6 , but also from the number of the sequence of these double signals the assignment of the individual bottom knives with respect to the zero mark and thereby identify the lower knife itself.

Moving a lower knife is described in more detail with reference to FIG. 2 for the lower knife I. Here, the lower knife I from the fully extended position I _is in the dash-dotted position I _should who moved.

In the embodiment shown here, a grip 13 is formed on the displacement device 8 as a horizon tal against the lower knife advanced or radially a pivotable fork, the jaw width is greater than the distance between the cutting edge 6 and the back edge 19 of the lower knife I.

Is the displacement device 8, starting from the zero mark 14, dealt with first retracted engaging means 13 les on the measurement bars 9 in the direction of the Pfeiffer 20 to the lower knife I, then it is first on the back edge 19 of the signal "1" and then from the Cutting edge 6 the "signal 2" delivered to the computer 12 . Due to the programming of the computer 12 , the shifting device 8 is switched to "creep speed" after the "signal 1" and then positioned exactly on the measuring bar 9 via the "signal 2", so that the distance I _{Ist of} the cutting edge 6 to the zero mark 14 can be recorded.

Now the engaging means 13 is advanced against the lower knife I, the finger serving as a stop 13.1 with its contact surface 21.1 at a precisely defined distance Δa from the bearing plane defined by the cutting edge 6 located on the lower knife I. The distance Δa is a system-fixed variable and is also taken into account in the programming of the computer 12 .

Now if the lower knife I from its position I _is with its cutting edge 6 in the position I _{should be moved} on the lower knife shaft 7, the displacement device 8 is driven with the help of its computer 12 controlled, here only schematically shown drive 22 in the direction of Arrow 23 moved. Here, the displacement device 8 is initially the distance Δa until its finger 13.1 comes to rest on the contact surface defined by the cutting edge 6 and can then be displaced up to the distance I _{Soll in} relation to the zero mark 14 . The total displacement distance Δs to be covered by the displacement device 8 is thus with I _actual + Δa - I _target . As soon as the displacement device 8 has positioned the lower knife I with its cutting edge 6 in its TARGET position I _target , the engaging means 13 is moved back so that the lower knife II and the lower knife III can subsequently be moved into its predetermined TARGET position.

However, if a lower knife is displaced with respect to the zero mark 14 in the direction of arrow 20 , with a finger 13.2 of the engagement means 13 coming into contact with the back surface of the lower knife, then it is necessary, in addition to the distance between the two edges 6 and 19 to the zero mark 14 also detect the difference in the distance between the two edges from one another via the displacement device 8 with the aid of the measuring device 12 . With the accuracy of the laser sensor, the distance between the cutting edge 6 and the back edge 19 can be detected precisely using this computing information. Since here again the Δb of the sensor 15 was present from the contact surface 13.2 as a system-immanent measure, the exact displacement distance for a lower knife in the direction of arrow 20 can be determined via the detection of the width b of the lower knife and via the Implement shifting device 8 .

The procedure described above can be done accordingly also use for lower knives that are fitted to knife holders Stigt that move on a corresponding traverse are stored bar and lockable.

In such an embodiment, the position of the respective cutting edge detected by the sensor. The intervention with tel the displacement device then act on the knife neck ter a, usually also one between the knife neck ter and the cutter bar existing parking brake released becomes.

If one assigns the cutter bar 1 , as indicated in FIG. 1, also to a shifting device 8.1 , the drive of which is linked to the computer 12 , then the knife holder 2 of the upper knife A, B and C can also be cut to by the cutting edge of the associated one Lower knife-predetermined cutting position after activation of a corresponding engaging means 13.3 acting on the knife holder 2 are moved and positioned.

A sensor system is not required for this displacement device 8.1 , since all the positioning operations via the sensor system of the displacement device 8 and the computer 12 are carried out.

When the travel drive of the displacement device 8 and the displacement device 8.1 are synchronized via the computer 12 , the mutually assigned upper and lower knives can be moved simultaneously.

The invention is not limited to that shown and described Design of measuring beam and displacement device as well limited their connection to the measuring device.

The term "measuring bar" in the sense of the present invention includes a track for the shifter and there with linked all systems that record the diff move on the track and the position of the shift establishment to a "zero mark" and the positioning to Control of the travel drive of the displacement device made possible lichen.

The drive can be switched on by a computer controlled stepper motor are formed, the one adjusting spindle or drives an endless belt with which the shifting device device is connected.

The drive can also be made by a running track and Shifter formed linear motor shown who the.

A measuring bar in the true sense is also possible, d. H. an impulsive track, in which integrated Ma gnette to the drive or a sensor connected to it corresponding impulses are given, which ver be working.

Fig. 3 shows a partial section of a so-called Tellermes water, which differs from the slot knife shown in Fig. 2 only in that both edges 6.1 and 6.2 are designed as cutting edges. In the assignment of the cutting edge 5 of the upper knife A to the cutting edge 6 of the lower knife I indicated in FIG. 1, only the edge 6.1 represents the "cutting edge" for the computer. After the edge 6.1 has worn , the knife is merely turned. The edge facing away from the upper knife always forms the "construction edge".

Fig. 4 shows a so-called cutting ring in partial section. This consists of a support ring 24 which is provided with a school ter 25 , on which a knife ring 26 is pushed. The knife ring 26 is firmly clamped via a locking ring 27 .

A total of four edges are thus detected by the sensor 15 as it moves past. Only the exposed edge 6.3 of the knife ring 26 then forms the "cutting edge" for the computer ner. All other contours are construction-related edges and therefore represent "construction edges" for the computer.

It is readily apparent that the direction of movement is important for signal acquisition.

When moving in the direction of arrow 28 , the signal "2" indicates the cutting edge 6.3 , while the signals "1", "3" and "4" indicate the construction edge.

When moving in the opposite direction (arrow 29 ), the cutting edge 6.3 is only indicated by the signal "3".

Claims (7)

1. A method for positioning knives, in particular un-knives on a device for slitting a mate rialbahn, in which an upper knife cooperate with a lower knife, the at least one with the respective knife to be positioned can be brought into engagement with engagement means with a measuring device in Connected, connected to a controllable drive device Verschiebeeinrich, characterized in that with the sliding device a sensor is moved past the Untermes to be positioned and thereby each of the edges of the lower knife successively generates a signal that from the given Assignment of the direction of movement of the sensor to the alignment of the cutting edges of the lower knives, the signals emanating from the sensor as "cutting edge" and as "construction edge" in the measuring device are identified, that the signal defines one of the edges, which is defined in the measuring device as "measuring edge" , preferably via the signal of the "cutting edge", the actual distance of the "measuring edge" to a base mark in the measuring device is detected (actual distance) and then the lower knife to be positioned after engagement of the displacement device is shifted until the predetermined distance of the "measuring edge" to the basic mark (TARGET distance) and the intervention is released again. 2. The method according to claim 1, characterized in that for the lower knife to be positioned when determining the Displacement between the actual distance and the target distance geometric conditions of engagement between displacements direction and the lower knife to be positioned in the measuring unit direction are taken into account.   3. The method according to claim 1 or 2, characterized in that the geometric intervention conditions to be taken into account due to the distance between the sensor and the means of engagement are specified. 4. The method according to any one of claims 1 to 3, characterized ge indicates that the Verschiebeinrich by a measuring run across the entire width of the facility in front of the position nation of the individual bottom knives the number of working knives the lower knife and its position to the base brand is detected via the signals coming from the sensor and that then the individual repositioned sub knives according to the specifications of the cutting program on their TARGET Distance to the base mark. 5. The method according to any one of claims 1 to 4, characterized ge indicates that after detection of the signal "construct onskante "the drive of the displacement device "Creep speed" controlled and via the signal "cutting channel te "is switched off. 6. The method according to any one of claims 1 to 5, characterized ge indicates that a laser emitter receiver Element is used. 7. Procedure for positioning upper knives on a one direction for slitting a material web, the one the Upper knives assigned, with the one to be positioned in each case Upper knife which can be brought into engagement by means of engagement means a controllable traction drive Verschiebeinrich device, in particular method according to claims 1 to 6, characterized in that the to be positioned Upper knife over the measuring device of the lower knife in relation is tracked to the assigned lower knife.