Advancing material of indeterminate length – With adherence or attraction of material to advancing means – By pneumatic pressure
Reexamination Certificate
2000-05-05
2001-12-11
Mansen, Michael R. (Department: 3653)
Advancing material of indeterminate length
With adherence or attraction of material to advancing means
By pneumatic pressure
C162S370000, C162S306000
Reexamination Certificate
active
06328194
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U.S.C. §119 of German Patent Application No. 199 21 202.3, filed on May 7, 1999, the disclosure of which is expressly incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a device for handling a material web, such as a paper or cardboard web in particular, in which the material web is guided along with a porous support belt over a suction roll, in particular a suction roll serving as a pick-up and/or transfer roll and having a perforated jacket, with the porous support belt being located in the region of the suction roll between the suction roll and the material web.
2. Discussion of Background Information
As a rule, in conventional devices of the kind mentioned above, a separately operated web-holding suction box or suction tube is provided subsequently to the pick-up and/or transfer roll. This necessitates a correspondingly greater energy expenditure. The desired vacuum must be produced in various places, for which purpose separate blowers are used, as a rule. Moreover, this results in a greater space requirement. Thus, in addition to the greater assembly cross-section, more conduits are also necessary. Not only must an additional blower be employed, there is also an increased expenditure for conduits.
SUMMARY OF THE INVENTION
The object of the invention is to create a device of the type mentioned at the outset which can be operated while keeping the structure as simple and compact as possible and with a substantially lower energy expenditure.
This object is attained according to the invention in that the suction roll has a suction zone in the approach region and the exit region of the material web that adjoins the inner side of the perforated roll jacket, in that the suction zone provided in the approach region is connected to a vacuum source, in that an outer web holding box or suction tube directly following the exit region is provided with suction by way of the suction zone located in the exit region, and in that this suction zone, which acts upon the web holding box or suction tube and is arranged in the exit region, is supplied with vacuum by way of the suction zone provided in the approach region and connected to the vacuum source.
Due to the combination of a suction roll with a web holding box or suction tube, this construction results in an energy-saving and compact functional unit with which a closed web guide can be realized in an optimal manner following the suction roll. Not only are the web holding box or suction tube provided with suction by the conveyed vacuum of the suction roll, the conveyed vacuum also serves to prevent blisters from forming before the subsequent nip, such that a corresponding stabilizing effect is achieved at the same time. Particularly with the aid of the constantly produced evacuated cavity air at the end of the suction zone, continuing adhesion of the web to the porous support belt is thus ensured. At the same time, a sound insulation is achieved at the suction roll. All in all, a cost-effective total solution results.
In a one-screen drying group described in DE 40 23 297 A1, a screen deflector roll is provided between two drying cylinders that, subsequent to an extended, continuous suction zone, has a further suction zone arranged before the exit region of the material web which can be embodied without a connection to the interior of the suction box or can be connected to the interior of the suction box by choke tubes. Neither a web holding box nor a suction tube is associated with this screen deflector roll.
In a useful practical embodiment of the device according to the invention, at least one intermediate suction zone is provided in the web travel direction between the suction zone located in the approach region of the material web and the suction zone located in the exit region of the material web. In this arrangement, the intermediate suction zone as well as the suction zone located in the exit region are supplied with vacuum by way of the suction zone located in the approach region, which is connected to the vacuum source.
More advantageously, the intermediate suction zone and/or the suction zone provided in the exit region are acted upon at least in part by the vacuum of the suction roll, which is conveyed in particular by way of the evacuated jacket holes.
In a useful practical embodiment, the suction zone provided in the approach region and the suction zone following it in the web travel direction are connected to one another by way of at least one choking point.
The porous support belt can, in particular, be formed by a felt.
In a preferred practical embodiment of the device according to the invention, the material web is removed from a felt by the suction zone of the suction roll provided in the approach region.
The suction roll can be provided between two presses, for example.
The present invention is directed to a device for handling a material web that includes a suction roll having a perforated jacket, and a porous support belt guided over the suction roll between a take-on region and a lift-off region. A surface of the porous support belt is adapted to guide the material web and the surface adapted to guide the material web is arranged away from a surface of the suction roll. The suction roll includes suction zones adjacent to an inner side of the perforated jacket, such that a first suction zone, arranged in the take-on region, is coupled to a vacuum source, and a second suction zone, arranged in the take-off region, is coupled to the vacuum source through the first suction zone. One of an outer web holding box and a suction tube is positioned subsequent to the take-off region, relative to a web travel direction, and is arranged to be suctioned by the second suction zone.
According to a feature of the invention, the suction roll can be adapted as at least one of a pick-up roll and a transfer roll. Further, the material web can include one of a paper and a cardboard web.
In accordance with another feature of the invention, the suction roll can further include at least one intermediate suction zone located between the first and the second suction zones in the web travel direction, and the at least one intermediate suction zone can be coupled to the vacuum source through the first suction zone.
According to another feature of the invention, at least one of the at least one intermediate suction zone and the second suction zone can be at least partially supplied with a vacuum conveyed through the evacuated holes in the perforated jacket.
In accordance with still another feature of the present invention, the first suction zone and the at least one intermediate suction zone can be arranged adjacent each other in the web travel direction through at least one variable choking point.
Further, the at least one intermediate suction zone and the second suction zone may be arranged adjacent each other in the web travel direction through at least one variable choked connection.
Moreover, the first, second, and at least one intermediate suction zones can each be formed as suction chambers which open to the inner side of the perforated jacket.
The device may also include sealing strips extending parallel to a roll axis and located between a stationary suction box and an inner side of the perforated jacket. The sealing strips may be arranged to define the first, second, and at least one intermediate suction zones in an inner circumferential direction of the suction roll by the sealing strips. A gap can be located between at least one of the sealing strips and the roll jacket to form a choking point, and the choking point can be positioned to couple the first suction zone to the at least one intermediate suction zone in the web travel direction.
In accordance with a further feature of the instant invention, the web holding box can be basin shaped.
According to a still further feature of the invention, a sealing element can be provided. The web holding box can have an openi
Greenblum & Bernstein P.L.C.
Mansen Michael R.
Voith Sulzer Papiertechnik Patent GmbH
LandOfFree
Device for handling a material web does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for handling a material web, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for handling a material web will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2559761