Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H23/00—Registering, tensioning, smoothing or guiding webs
  • B65H23/02—Registering, tensioning, smoothing or guiding webs transversely
  • B65H23/032—Controlling transverse register of web
  • B65H23/038—Controlling transverse register of web by rollers

Definitions

• the invention relates to a device of the type specified in the preamble of claim 1 and a method according to the preamble of claim 16.
• the guiding effect is based on the clamping force between the control roller and the counter-roller which, because of the inclined position, generates a web offset correction force acting transversely to the web running direction.
• Signals generated when the edge positions are scanned control the force transmitter for the control roller. If the scanned edge moves outwards, the clamping force is released and the control roller is lifted off. If, on the other hand, the edge strives inwards, the control roller is pressed against the counter roller with the set clamping force.
• the opposite web guide works accordingly. The control roller is either pressed with the set clamping force or completely relieved.
• the invention has for its object to provide a device and a method of the type mentioned with which a gentle, jump and flutter-free guiding and holding a running web is made possible, and with which one standing web can be kept wide.
• the device is also expediently designed such that, in a limit case of the web offset when the roll engagement length limit is undershot for one web guide, the clamping force on the opposite web guide is completely eliminated in order to make it easier for the web guide to correct the web misalignment.
• the undesired pressure markings are omitted, because when the clamping force is reinstated, it is gradually increased and there is no sudden pressing of the rollers. If the length limit is reached, at which the rollers of this web guide are only partially in engagement with the web, then under certain circumstances even the full clamping force may no longer be sufficient to overcome the counter-pull of the other web guide, which acts with minimal clamping force. However, as soon as the clamping force on the opposite and fully engaged web guide is released, the slight intervention of one web guide with full clamping force is usually sufficient to correct the web offset.
• the embodiment according to claim 6, which has two web guides.
• the falling below the roll engagement length limit value can easily be determined by the scanning devices.
• the control devices react and adjust the force transmitter towards zero, the web operator of which is still fully engaged.
• the other web guide alone corrects the web offset.
• the force transmitter it is easily possible for the force transmitter to be adjustable continuously or in several predetermined steps until a minimum length and maximum force value is reached for a web train operator until the permissible roller engagement length limit is reached. With continuous adjustment, the cross elasticity of the web is optimally used. If, on the other hand, adjustment is made in several predetermined stages, this means a simplification in terms of control technology with a reliable Bah offset correction.
• the embodiment according to claim 8 is expedient because a broadband proportional sensor has a large active proportional range and generates clear signals that can be converted into unambiguous control signals for the force transmitters.
• a closed control loop is achieved via the goods path.
• Proportional magnets can be obtained inexpensively with exactly known and constant characteristics. They are functionally reliable and precisely adjustable. Such proportional magnets are characterized in that the magnetic force generated is directly proportional to the current applied, so that the proportional magnet fulfills the function of a spring which is adjustable in its spring hardness without changing the characteristic curve. Proportional magnets can be easily Control via a current regulator.
• the window comparator monitors the position of the web for the proportional control of the two proportional magnets.
• the first timing element is used to switch off the current regulator of the proportional magnet, in whose web guide there is still full engagement when the roller engagement length limit value is reached in the other web guide.
• the timer is activated as soon as the window comparator detects this critical web offset. If the web offset remains for the period of time set on the first timing element, the current controller is switched off in order to enable the web guide to make the correction with the lesser roller intervention.
• the embodiment according to claim 12 is advantageous because the components provided here help to avoid damage to the web or the device. If, in spite of the currentless current regulator, the web guide operating with little intervention is not able to correct the web offset, for which the first time element provides him with time, then the second time element actuates a warning signal after the set time period has elapsed , which indicates an error to the machine operator or even a switch that stops the web.
• the force transmitter used is a pneumatic diaphragm cylinder with an actuating force proportional to the compressed air supply for the control roller or a prestressed spring element which is adjustable in the prestress.
• Pneumatic membrane cylinders which are particularly useful in potentially explosive atmospheres or in the case of wet material webs, can be adjusted very sensitively by modulating the application pressure or by means of an inlet or outlet regulator. Although a change in the characteristic curve can hardly be avoided in the case of a spring element when the pretension is changed, it is nevertheless a continuous adjustment of the clamping force in a simple manner, for example. by means of a spindle or lever drive which adjusts the spring preload.
• the clamping force is gradually increased in order to avoid undesired pressure markings.
• Very slight tension fluctuations in the transverse direction of the material web are achieved with certainty in a method variant if the clamping force at one edge area is changed in inverse proportion to the clamping force at the other edge area until the roller engagement length limit value is reached for a web guide.
• the method variant according to claim 15 is also advantageous because the two proportional magnets generate their magnetic forces in strict dependence on the position of the web in the scanning area.
• the current supply that is preferably specified is intended for a customary size of a web guide. With a considerable change in the size and the actuation mechanism, the range of suitable current application changes.
• the method variant according to claim 16 is particularly advantageous because the guiding and spreading of the web is carried out with high security against damage. No edge area is completely released within a normal web offset area.
• the clamping force on the other web guide is released after a predetermined first period of time only after falling below the roller engagement in one web guide in order to increase the corrective effect. If, nevertheless, the web offset is not corrected, a warning signal is generated after a further second period of time or the web is stopped in order to avoid serious damage.
• Figure 1 is a schematic plan view of a device for guiding and spreading a web
• Figure 2 shows a specific embodiment of a web guide in and 3 two mutually associated views.
• a device V for guiding and spreading a web B running in the direction of an arrow 8 consists of two web guides W a. and W 2 , which act on the edge regions K x and K-.
• the two web guides W 1 ⁇ W 2 are inclined at an angle ⁇ against the right angle to the web direction 8.
• Each web guide W 1 ⁇ W 2 includes a control device S 1 5 S 2 , which are expediently combined in a common control device R, which also contains an amplifier A.
• a window comparator F is provided in the control unit R, which is connected to the current regulator SR a , SR 2 .
• Each current regulator SR 1 ⁇ SR 2 can be switched off via a first, preferably adjustable, timer Z_ which can be activated by the window comparator F.
• a warning signal generator G With a second timer Z 2 , which is connected to the window comparator F like the first timer Z x , a warning signal generator G can be actuated, or a main switch (not shown) for the
• Each web guide W 1 ⁇ W 2 has ( Figures 2 and 3) a lower control roller 1 and an approximately parallel upper counter roller 2.
• the rollers 1, 2 enclose the respective edge area K a , K 2 of the web B between them.
• a scanning device 4 is arranged in the web running direction 8 behind the rollers 1, 2.
• the control roller 1 is movably mounted on a power transmitter 3 relative to the counter roller 2. Both rollers 1, 2 are either freely rotatable or can be driven to rotate at the speed of the web B by means of an additional drive (not shown).
• Each force generator 3 of a control roller 1 is continuously adjustable in such a way that the clamping force between the two rollers 1, 2 can be continuously changed without releasing the web.
• a proportional magnet 14 is connected via a line 5 to the control device S a or Sz, as are the scanning devices 4 via lines 6.
• a line 7 links the two control devices S ⁇ , S 2 . In the direction of travel behind the web guides Wi, W 2 , the web B is guided over a deflection roller 9.
• both web guides Wi, W 2 apply a clamping force to their edge areas K_ K 2 .
• the goods- railway B is being spread out. If the material web B runs to the right in the running direction 8 in FIG. 1, for example, the scanning device 4 generates a signal corresponding to the edge position.
• the force transmitter 3 is adjusted to a lower force value, so that, thanks to the clamping force in the web guide W 2, the web B is pulled to the other side and the web run is thus corrected again. With a course in the reverse direction, these processes take place in reverse.
• the clamping forces in both edge areas K_ K 2 can be changed synchronously in opposite directions.
• a proportional magnet 14 is provided as the force generator 3, the magnetic force of which is proportional to that of the current regulator SRa. or SR 2 controlled current strength changed continuously.
• a proportional magnet 14 instead of a proportional magnet 14, however, a pneumatic diaphragm cylinder could also be provided, the actuating force of which for the control roller 1 can be directly varied in proportion to the pressurization.
• a force element 3 it is also conceivable for a force element 3 to be a spring element, for example. to use a helical spring, the pretension of which is changed continuously and in stages or continuously. Electric motors or similar proportionally adjustable power transmitters could also be used.
• the two rollers 1, 2 are mounted approximately parallel to one another in a holder 13.
• the control roller 1, which must be adjustable, is seated on a support part 12 on which the force generator 3 acts.
• the scanning device 4 is a broadband proportional sensor with a lower part 10 and an upper part 16, which are likewise fastened to the holder 13.
• the bracket 13 can be fixed by means of a support 15 in the desired inclined position (angle ⁇ ) relative to the track on a frame, not shown.
• the control device can be attached directly to one of the two web guide or integrated and connected to the other web guide via appropriate cable connections.
• the window comparator F is used for proportional control of the proportional magnets 14 of the two web guides W x and W 2 via the current regulators SR X , SR 2 . If a normal web offset occurs, in which the rollers 1, 2 of the web guide are in engagement with the edge region at least up to 60 or 70% of their length L, the clamping force on a web guide is never completely eliminated, but rather the Clamping forces changed proportionally to the web position. However, if there is a web offset at which a roller engagement length limit value Q (FIG.
• the timer Z ⁇ switches after lapse Chen the period of time, the current regulator SR ⁇ or SR 2 of the proportional magnet 14, in whose rollers 1, 2 there is full engagement. The clamping force is completely eliminated there, if necessary the control roller 1 is lifted off completely.
• the second timer Z 2 is then activated.
• the window comparator F monitors over the period of the second timer Z 2 whether the material web B is corrected properly and in the positive case then turns off the second timing element Z 2 and the previously switched off current regulator SR ⁇ , SR 2 again to the minimum current value (150 mA).
• the signal generator G is actuated to warn the machine operator or the main switch is actuated to stop the web B and prevent further damage.
• the complete removal of the clamping force on both web guides W 1 ⁇ W 2 can also be set arbitrarily for threading the web B when starting up or after a shutdown. In normal operation with a normal web offset, the method described at the outset is used.
• the device is designed so that it serves to guide the center of the web B and has two web guides Wi, W 2 .
• the control roller 1 is pivotally mounted on its support part 12, so that it is able to apply exactly parallel to the counter roller 2.
• this position of the control roller 1 it is achieved that when the clamping force is increased, it is initially highest near the free edge and lower toward the center.

Landscapes

• Registering, Tensioning, Guiding Webs, And Rollers Therefor (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6404665

Family Applications (1)

Country Status (4)

Cited By (1)

Families Citing this family (5)

Citations (5)

• 1990
  • 1990-04-19 DE DE4012488A patent/DE4012488C2/de not_active Expired - Fee Related
• 1991
  • 1991-04-18 BR BR919105712A patent/BR9105712A/pt not_active Application Discontinuation
  • 1991-04-18 DE DE59106018T patent/DE59106018D1/de not_active Expired - Fee Related
  • 1991-04-18 EP EP91907813A patent/EP0479992B1/de not_active Expired - Lifetime
  • 1991-04-18 DE DE91EP9100741T patent/DE4190843D2/de not_active Expired - Fee Related
  • 1991-04-18 WO PCT/EP1991/000741 patent/WO1991016258A1/de active IP Right Grant

Patent Citations (5)

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