JP2804810B2 - Web supporting turning extension device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for contactlessly supporting, turning and spreading a web, in particular a coated paper web or a coated board web. The apparatus includes a transport surface that bends according to the turning of the web, and in connection with the transport surface, the web travels supported by air flowing between the transport surface and the web; The nozzle member includes a guide surface and a transfer surface provided in relation to the guide surface, and a gas such as air passes through a nozzle in the nozzle member in a direction perpendicular to the traveling direction of the web with respect to the transfer surface. Blown out,
On one side, the nozzle is defined by the guide surface, or a conveying curved surface provided in the vicinity of the guide surface is formed by a conveying surface of the nozzle member, which is substantially parallel to the running of the web to be supported. The shape is determined, and the present apparatus includes a floating nozzle box as a first nozzle box and a last nozzle box in a web running direction, and in each box, nozzles blowing toward each other form a pressurized conveying surface. I do.

BACKGROUND ART Regarding the prior art of the present invention, European Patent Application 8710241
See 1.3, 83303143.8, and U.S. Pat. No. 4,218,833.

For some typical applications of the use of the device according to the invention, reference is made to the applicant's Finnish patent 67,586 (equivalent to Canadian patent 1,221,569).

With regard to the prior art which is most closely related to the present invention, reference is made to the apparatus described in the applicant's Finnish Patent 64,335, especially for the contactless support, spreading and possible deflection of a coated paper web or coated board web. In this device, the nozzle member includes a guide surface and a pressure surface located between the surfaces. On both sides of the pressure surface, nozzle holes are provided with their longitudinal direction oriented transverse to the web running direction. Finnish patent 64,335
The novelty of the signal is that the ratio of the width of the nozzle hole to the radius of curvature of the guide surface is chosen as follows. That is, due to the generated flow, the gas flow proceeds along the guide surface to the pressure surface, and in addition, the end defining the nozzle opening of the intermediate surface is acute, thereby preventing the gas flow from returning to the intermediate surface. I have.

Purpose The present invention overcomes such disadvantages of the prior art devices,
The main aim is to improve the implementation deficiencies noted by developing the device described in Finnish Patent 64,335. The disadvantage of the device according to Finnish Patent 64,335 is that, in all applications, it is not possible to give the desired spreading effect to the web, or to provide a suitable transverse guiding effect, without making transverse folds in the area of the device. Can not be obtained.

Test runs and studies on test machines indicate that running the web is extremely difficult with uneven web tension. Further, in some conventional turning machines for actual production, an attempt has been made to provide a detecting device at a tightening point of the device in consideration of this factor. In such a case, the operator can change the pulling force and running of the web as needed while watching the display. In this conventional apparatus, the pressure is not strictly adjusted, but the adjustment is performed by changing the position of the apparatus or the roll.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a more efficient web spreading and guiding device.

It is another object of the present invention to provide a device that requires less air than conventional corresponding devices.

Another non-essential object of the present invention is to provide an apparatus that eliminates web running problems arising from uneven web tension.

Another non-essential object of the present invention is to provide an apparatus capable of removing blown air so that dry hot air can be blown through nozzles in the apparatus to dry the material web to be supported and diverted. It is to be.

To achieve the objectives set out above and below,
The present invention is characterized by having a pressure equalizing pocket provided between nozzle boxes and a common pressure equalizing chamber communicating with the pressure equalizing pocket.

The device according to the invention is intended for contactless air support of a paper or board web, simultaneous spreading and turning. In the device according to the invention, the turning angle is variable within a relatively wide range, for example in the range from 0 ° to 180 °, but in a preferred application of the invention, the turning angle a =
It ranges from 60 ゜ to 180 ゜. At a turning angle a = 0 ° the web does not turn at all, but the device operates only as a contactless spreading and supporting device. In this case, all the advantages of the present invention are not attained at least to their fullest extent.

The foil nozzle used in the present invention extends the web in its lateral direction to prevent wrinkling in the web. The foil nozzle itself reduces air consumption. this is,
In particular, in the lateral or lateral regions the air flows substantially parallel to the web. The blown air directed against the web running direction prevents air from leaking from the outlet side. The air flowing along the web from the intake or entrance side has a sealing effect by itself.

In the present invention, there is preferably a pressure pocket between the nozzles, which is sufficiently large to keep the pressure between the web and the diverter constant, even if the disturbance to the web is great.
The pressure pockets between the nozzles are desirably connected to the same pressure chamber. In this way, the distance of the web from the turning device remains unchanged, since the pressure in the pressure pockets is equal.

In some cases, the turning device according to the invention may be used as a dryer. This is because humid circulating air can be removed from the pressure chamber. In this regard, the small amount of leaking air from the device to the machine installation site allows the use of the superheated air.

In an advantageous embodiment of the invention, the end of the pressure pocket is provided with a nozzle-type end seal, which reduces air leakage at the end.

In the apparatus of the present invention, it is preferable to regulate the pressure in the transverse direction, thereby avoiding difficulties in drawing the web, mainly due to non-uniform forces pulling the web in the transverse direction.

DESCRIPTION OF THE EMBODIMENTS Next, with reference to the accompanying drawings, embodiments of a web supporting and turning apparatus according to the present invention will be described in detail. However, the invention is not limited by the details of these examples.

The overall structure and operation of the device according to the invention is shown in FIGS. The device comprises a series of nozzle boxes 10, which include nozzle boxes 20, 30 at ends 11a, 11b.
And are interconnected by a flat wall plate 13. In the series of nozzle boxes 10, necessary blowing air on the transfer curved surface k is supplied via pipes 14 a and 14 b, and these pipes communicate with the intake duct 15. The blown air is supplied from a blower (not shown) to an intake duct 15 having a closed end 15a in the direction of arrow Ain. From the pipes 14a, 14b, 14c provided with the damper 16, the blown air passes through the block 17 to the insides 23, 33 of the nozzle boxes 20, 30.

As shown in FIG. 2, the wet web W supported and turned in a non-contact manner is usually coated on one side or both sides, and sent from a coating apparatus or a size press in the direction of arrow Win. come. The web Wout leaves the device after turning at an angle a through the transport surface K. The angle a is variable within the range of a = 0 to 180 °. Typically and optimally, the turning angle a is in the range a = 60-180 °. The number of nozzle boxes 20, 30 required for the device depends on the turning device a.

As shown in FIG. 1 and FIG.
The first nozzle box is a pressurized, so-called floating nozzle box 20, and a similar nozzle box is provided as the last nozzle box of the device. As shown in FIG. 3, three foil nozzle boxes 30 having a negative pressure are provided between the pressurizing nozzle boxes 20. The number of foil nozzle boxes 30 depends on the turning angle a, usually 1
~ 6. In some special applications, if the turning angle a is very large, a third floating nozzle box
20 may be arranged between the foil nozzle boxes 30.

An essential feature of the present invention is that there is a relatively wide, intermediate space between the nozzle boxes 20, 30, which spaces act as pressure pockets and communicate with the pressure equalization chamber 12. In addition, these spaces extend laterally over the entire width of the web W, and by these means it is possible to control draw or draw problems due to uneven tension of the web W.

As shown in FIG. 3, the pressurized floating nozzle box 20 includes side walls 24, 25 and a bottom wall 22, with the side walls 24 and 25 defining a lateral duct 21 therebetween. The outside of the floating nozzle box 20 is a substantially flat transfer surface 27, on both sides of which the Coanda surfaces 28a and 28b having a radius of curvature R are attached, and the bent surface portions 25a and 25b face the Coanda surfaces 28a and 28b. Provided. The transfer surface 27 may be concave, that is, may have a dent when viewed from the outside. Nozzle parts 25a, 28a and 2
5b, 28b define nozzles 26a and 26b therebetween, and the blows F1 facing each other are blown through the nozzles 26a and 26. Inside the side box 21, there is a nozzle box
Blowing air is guided from the inside 23 of the device 20 in the direction of arrow L2. Air is supplied to the nozzle box 20 via a duct 17. On the transport surface 27 of the transport area K, a balloon F1
Form a region of positive pressure K +, from which air is discharged outward at the intake side Win of the web W, as indicated by the arrow F3, and outward on both sides of the web W, as indicated by the arrow Fv (fourth). Figure).

The foil box 30 has side walls 34, 35, a bottom wall 32, and a transfer surface 3.
It is composed of 7. Foil box 30 is side duct 3
1 which is defined by sidewalls 34 and 35. Wall 35
As an extension of this, there is a fold 35a, which together with the inner wall 34 and the Coanda curved surface 38 defines a nozzle hole 36. The Coanda curved surface 38 is formed by extending the inner wall 34 as it is. The blowout F2 is emitted through the nozzle hole 36, guided by the Coanda curved surface 38, turned, and becomes parallel to the transport surface 37. Speech bubble
F2 is oriented in the opposite direction to the running direction of web W. The blowing air reaches the inside 33 of the foil box 30 via the duct 17. The blown air enters the side duct 31 from the internal space 33 in the direction of the arrow L3, and further reaches the transfer surface 37 as a foil blowout F2.

The blowing F2 creates an area of negative pressure K- by the foil effect. From the area of negative pressure K- and the area of positive pressure K +,
The air is sucked into the intermediate space 18 in the direction of arrow F4, and further reaches the pressure equalization chamber 12 in the direction of arrow F5.

In the transverse direction of the web, the blow boxes 20 and 30 are divided, for example, into three blocks by transverse partition walls.
Each block receives its own blown air via a respective intake duct 14a, 14b, 14c. The amount of blown air that can be supplied to each block is controlled by an adjustment damper 16. By this adjustment, the running of the web W can be stabilized, and problems caused by changes in the tensile force of the web can be eliminated.
With the adjustments described herein, it is not necessary to change the position of the device and to measure the force applied to the device.

An essential feature of the present invention is the use of a pressure equalization chamber 12. The equalizing chamber 12 extends over the entire width of the series of nozzle boxes 10 and the web W, that is, between the end walls 11a and 11b. Due to this relatively large capacity of the equalizing chamber 12 and the intermediate space 18, the distance of the web W from the conveying surfaces 27, 37 in the turning device is kept substantially constant irrespective of the change of the web tension. You.

If necessary, air removal from the pressure chamber 12 can be performed to remove humid circulating air from the equalization chamber 12. This air removal is illustrated by a blower 40 and a discharge pipe 41 shown schematically in FIG. In such a case, duct 15
This apparatus can be used as a dryer by supplying dry high-temperature air to the apparatus via the above.

FIG. 4 shows the sealing device in section D of FIG. 1, ie the side or lateral area WR of the web W. A corresponding sealing device is also provided at the opposite end of the web W. The set of boxes 10 includes walls 40. Wall 43
And 44 define a nozzle 42 therebetween. These nozzles extend over the entire length of the transport surface K, that is, over a sector a in the apparatus direction, or extend obliquely to this sector. The blowing direction F6 of the nozzle 42 is the web W
, I.e., facing the leaked air flow FV. A labyrinth seal is provided inside the nozzle 42. This seal consists of plates 43 and 44 which are oriented towards or relative to the machine direction and, together with the blowout F6, reduce the leakage airflow FV. The ends of the seals 43 and 44 are at a distance E to the web W. Accordingly, the ends of the seals 43 and 44 have the same bend as the turning sector a of the web W. The outermost part of the sheet device shown in FIG. 4 is constituted by an outer wall 46 placed in the direction of the device and a partition wall 45 provided opposite the web WR.

The details of the invention can be varied and modified within the scope of the inventive idea indicated in the claims.

In summary of the invention, the paper web is supported without contact,
It is a device for turning and spreading. This device comprises a curved surface K which is bent according to the turning of the web, in relation to which the web W runs with the air flowing between the curved surface K and the web W supported. The nozzle member in the device is
Including a guide surface 28a, 28b, 38 and a transfer surface 27, 37 provided in relation to the guide surface 28a, 28b, 38, a gas such as air is passed through a nozzle hole 26a, 26b, 36 in a nozzle member. W is blown onto the transport surfaces 27 and 37 in a direction perpendicular to the traveling direction of W. The nozzle holes 26a, 26b, 36 are, on one side, defined by guide surfaces 28a, 28b, 38. The air support surface K in the apparatus is provided on the floating nozzle box 20 and the foil nozzle box 30, and the transfer surfaces 27, 37 substantially parallel to the running of the web W to be supported.
Is defined by In the traveling direction of the web W, the first nozzle box and the last nozzle box are floating nozzle boxes 20, and in these floating nozzle boxes 20, the nozzles 26a, which blow out to each other,
26b forms a pressurized transport surface K. Between these floating nozzle boxes 20, one or several foil nozzle boxes 30 are provided. The nozzle box 20, 30
A pressure equalizing pocket 18 is provided between them.

[Brief description of the drawings]

FIG. 1 is a view of the apparatus according to the present invention viewed from the machine direction. FIG. 2 is a vertical sectional view taken along the line II-II of FIG. 1. FIG. FIG. 4 is a vertical sectional view of the first two nozzle boxes, FIG.
FIG. 4 is a lateral vertical sectional view of a portion. Explanation of reference numerals of main parts W ... Web K ...... Curved surface 18 ... Pressure equalization pocket 20 ... Floating nozzle box 30 ... Foil nozzle box 26a, 26b, 36 ... Nozzle hole 27,37 ... Conveying surface 28a , 28b, 38 …… Guideway

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Perutti Heikkila Finland 21260 Laccio Numempaankatu 5B18 (72) Inventor Ilkka Jokioinen Finland 21420 Rieto Saukonoyanje 16 (56) References Tokugyo Sho44- 11451 (JP, B1) JP 52-12476 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65H 20/14 B65H 23/24

Claims (13)

(57) [Claims] An apparatus for supporting, diverting and extending a web, in particular a coated paper web or a coated board web, in a contactless manner, the apparatus comprising a conveying device which bends according to the turning of the web. A curved surface, wherein the web travels while being supported by air flowing between the transport curved surface and the web, and the nozzle member of the device includes a guide surface, and a transport surface provided in relation to the guide surface. Including, gas through the nozzle in the nozzle member, such as air, is blown onto the transport surface in a direction perpendicular to the running direction of the web, the nozzle is shaped from one side by the guide surface, Alternatively, the shape of the transfer curved surface of the apparatus is provided near the guide surface, and the shape of the transfer curved surface of the device is determined by the transfer surface of the nozzle member, which is substantially parallel to the running of the web to be supported. The apparatus includes a floating nozzle box as a first nozzle box and a last nozzle box in the running direction of the web, and in each box, the nozzles blowing toward each other form a pressurized conveying surface. A web supporting and diverting and spreading device, comprising: a pressure equalizing pocket provided between the nozzle boxes; and a common pressure equalizing chamber communicating with the pressure equalizing pocket. Turning extension device. 2. The apparatus according to claim 1, wherein the apparatus has at least one foil nozzle box between the first floating nozzle box and the last floating nozzle box; A web support turning and spreading device, wherein the shape is determined by the conveying surfaces of the floating nozzle box and the foil nozzle box. 3. The device according to claim 1, wherein
The web-supporting turning and spreading device, wherein the common pressure equalization chamber maintains the pressure between the web and the device substantially unchanged regardless of web disturbances such as changes in tension. 4. Apparatus according to claim 1, wherein said pressure pockets are connected to the same common pressure equalization chamber, said equalization chamber being present over substantially the entire width of said web; An apparatus for supporting and turning webs, wherein the distance between the transport surface of the apparatus and the web is kept substantially unchanged. 5. The apparatus according to claim 2, wherein the apparatus is associated with the nozzles of the floating nozzle box and the foil nozzle box.
A curved Coanda surface is provided, the Coanda surface being arranged to deflect the blowing air flowing through the nozzle and direct it towards the transport surface, which is most preferably planar, A web support turning and spreading device, which is formed by being extended as it is. 6. An apparatus according to claim 2, wherein a Coanda nozzle is provided in the foil nozzle box at one end of the box, and the blowing direction of the Coanda nozzle is such that the web travels. A web-supporting turning and spreading device characterized by being opposite to the direction. 7. An apparatus according to claim 2, wherein a Coanda nozzle is provided in one end of the foil nozzle box, and a blowing direction of the nozzle is a running direction of the web. A web support turning and spreading device, which is in the same direction as the web. 8. Apparatus according to claim 2, wherein the apparatus comprises one or several, optimally two to five, between the floating nozzle boxes depending on the turning angle. A web-supporting turning and spreading device comprising a plurality of foil nozzle boxes. 9. The apparatus according to claim 2, wherein air blows out from a nozzle hole at an end of the last floating nozzle box at an outlet side, and air escapes from an outlet side of the curved transfer surface. A web supporting and diverting and spreading device, wherein the air entering the web inlet side seals the conveying curved surface by itself. 10. Apparatus according to claim 1, wherein at both ends of the web there is provided a lateral sealing of a nozzle type to reduce leakage at both ends of the web. A web-supporting turning and spreading device, characterized in that: 11. The apparatus according to claim 1, wherein a lateral sealing of a nozzle type is provided at both ends of the web, and a blowing direction of the sealing is an outlet side of the apparatus. And a web supporting and turning device which is directed obliquely inward or outward to enhance the web spreading effect of the device. 12. The apparatus according to claim 1, wherein the apparatus controls the pressure in a lateral direction by dividing the nozzle box into blocks in a lateral direction of the web. The blocks are supplied with an air flow of an adjustable amount or pressure, which regulates the running of the web and the distance of the web from the conveying curve against changes in the tensile force of the web. A web-supporting turning and spreading device, comprising: 13. Apparatus according to claim 1, wherein the apparatus is further used as a web dryer and for this purpose communicates with the pressure pockets between the nozzle boxes. A web support turning and spreading device for removing wet circulating air from a common pressure equalization chamber.