Applicator of a machine for producing a fibrous web and machine for producing a fibrous web

Abstract

The invention relates to an applicator (7) for a machine for producing a fibrous web, for applying air to a moving fibrous web manufactured by the machine, the applicator comprising a housing (701) forming a cavity (702) adapted to receive air, the housing being adapted to extend in a web width direction transverse to a web movement direction and having a main body extension of the housing, wherein the housing comprises a distribution plate (703) having a plurality of distribution holes (704) to distribute air along the width of the web, wherein the applicator comprises a cleaning device (705, 709, 711, 712) extending along the main body extension of the housing and being adapted to apply a liquid on the distribution plate (703).

Description

Technical Field

[0001] The present invention relates to an applicator for a machine for producing fiber webs, for applying, for example, process air to a moving fiber web produced by the machine, and to a machine for producing fiber webs. Background Technology

[0002] In tissue paper manufacturing technology, it is desirable to increase the productivity of machines used to produce fiber webs and / or reduce the energy consumption of such machines. To reduce energy consumption, hot process air from one stage of the machine process can be used in another stage of the machine process.

[0003] US 9702084B2 describes a machine for manufacturing tissue paper webs. A first hood is positioned opposite a suction roller. A Yankee dryer is covered by a second hood, from which hot waste air is supplied to the first hood via a duct and used to supply humidified air. The humidified air is then drawn through the tissue paper web by the suction roller, causing moisture to condense on the web, thereby raising the temperature of the tissue paper web before it passes through the stretching and pressing zone. Consequently, the viscosity of the water in the web decreases, making it easier to remove by the suction roller.

[0004] In process air heat recycling applications, it is desirable to avoid excessive buildup of particles (such as fibers) on the equipment used for heat recycling. If such buildup occurs, operators may have to remove some equipment and clean it manually. This may require machine downtime, which will inevitably reduce productivity.

[0005] WO 2021063563A1 describes an applicator for applying process air to a traveling fiber web. For maintenance purposes, a diffuser can be removed from the applicator, and a replacement diffuser can be inserted into the applicator after the contaminated diffuser has been removed.

[0006] Nevertheless, it is desirable to provide a system that is easy to operate to ensure the cleanliness of the applicator used to apply, for example, process air to the fiber web. Summary of the Invention

[0007] One object of the present invention is to provide a method for ensuring the cleanliness of an applicator used to apply air to a fiber web in a machine for producing fiber webs, the method being simple to operate.

[0008] This objective is achieved by an applicator for a machine used to produce fiber webs, the applicator being used to apply air to a moving fiber web manufactured by the machine. The applicator includes an envelope forming a cavity adapted to receive air, the envelope being adapted to extend in a web width direction transverse to the web movement direction (preferably along the entire width of the web), thus having a main extension of the envelope. The envelope includes a distribution plate having a plurality of distribution holes for distributing air along the width of the web. The applicator includes a cleaning device extending along the main extension of the envelope and adapted to apply liquid to the distribution plate. This applicator can be used to apply process air, such as humid hot process air.

[0009] The dispensing plate can be cleaned using a cleaning device. Liquid cleaning effectively removes fibers that have accumulated and adhered to the surface of the dispensing plate. This cleaning can be performed automatically, requiring no manual handling. Therefore, the cleaning operation remains simple and does not require shutting down the machine. This avoids reducing machine productivity.

[0010] The cleaning device is suitable for applying liquids that can be water or liquids containing water.

[0011] Preferably, the cleaning device is disposed outside the housing. The cleaning device may have a groove for liquid application. Therefore, the groove may be disposed at the upper edge of the dispensing plate.

[0012] In some embodiments, the cleaning device includes a spray bar.

[0013] In some embodiments, the cleaning device is disposed inside the housing.

[0014] Therefore, even if the plate is tilted so that the inner surface to be cleaned is facing downwards, the liquid can still flow over the entire surface. Thus, due to cohesion, the liquid can remain adhered.

[0015] In some embodiments, the cavity may be divided by a wall into sub-cavities distributed along the transverse direction of the web. Therefore, the internal portion of the cleaning device may include components distributed into the sub-cavities for cleaning them.

[0016] In some embodiments, the cleaning device is disposed outside the housing. Therefore, the applicator may include an additional cleaning device that extends along the body of the housing and is adapted to apply liquid to the dispensing plate, wherein the additional cleaning device is disposed inside the housing.

[0017] In some embodiments, the dispensing plate is curved to mate with rollers (e.g., suction rollers). In some embodiments, the dispensing plate is flat to mate with flat portions of the web path. Regardless of whether the dispensing plate is curved or flat, there may be an external cleaning device or an additional internal cleaning device, which may have a groove for liquid application. This groove may be located at the upper edge of the dispensing plate.

[0018] In some embodiments, the applicator includes a retraction actuation assembly, by which the housing, when mounted in the machine, is adapted to retract away from the web. Thus, the dispensing plate can be kept at a distance from the web, allowing the outer surface of the plate to be cleaned using an external cleaning device. Once the cleaning action is complete, the housing can move back to its working position.

[0019] When the applicator is in use and air is applied to the web, the distance between the dispensing plate and the web is preferably less than 100 mm to ensure proper air application to the web. A suitable range can be 30 to 100 mm. If a retraction actuation assembly is provided, or if the dispensing plate can be otherwise moved to a cleaning distance suitable for cleaning, the cleaning distance is preferably at least 200 mm. A cleaning distance of at least 200 mm allows machine operation while cleaning the dispensing plate is being performed.

[0020] In some embodiments, the distribution plate may be fixedly arranged, for example, at a distance of 30 to 100 mm from the fiber web.

[0021] In some embodiments, the cleaning device is movable relative to the housing to move along the dispensing plate. This mobility can be provided by one or more actuators, which can be of any suitable form, such as pneumatic or hydraulic cylinders. Thus, the cleaning device can move in a direction transverse to the width of the fabric. A guide device (e.g., a track) can be provided to guide this movement. If the dispensing plate is curved, the guide device can be curved to allow the cleaning device to conform to the curvature of the plate.

[0022] Preferably, the extension (length of extension, direction of extension) of the dispensing plate extending transversely to the main body of the housing is configured such that, when air is applied to the web by the applicator, the dispensing plate extends no more than 500 mm, preferably no more than 400 mm, and most preferably no more than 300 mm, along the web in the web moving direction. Therefore, more effective cleaning can be achieved by the cleaning device.

[0023] The extension of the distribution plate transverse to the main body of the housing can be configured such that, when air is applied to the web by the applicator, the distribution plate extends at least 100 mm along the web in the web movement direction. This ensures, for example, a uniform and smooth flow suitable for tissue paper webs.

[0024] Preferably, the area of ​​each dispensing hole is at least 28 mm. 2 Preferably at least 50 mm 2 Preferably at least 78 mm 2 For example, if it is circular, the diameter of the dispensing hole is preferably at least 6 mm, preferably at least 8 mm, and preferably at least 10 mm. This reduces the likelihood of particles clogging the hole.

[0025] The distribution plate may include or have multiple distribution holes arranged in a grid pattern to distribute air along the width and length of the web. This ensures, for example, a uniform and smooth flow suitable for tissue paper webs.

[0026] Preferably, the dispensing plate includes a coating of low-friction material. The coating is preferably applied to both the outer and inner surfaces of the dispensing plate. This material can be PTFE (polytetrafluoroethylene), such as Teflon®. For example, the material could be AR105 Teflon® or AR620 MicroCoat®. This reduces particle adhesion and makes it easier to remove particles from the cleaning device with liquid. The coating can be applied to the inner and / or outer surfaces of the dispensing plate. Alternatives to the low-friction material could be NYLOIL® (nylon with additives), PEEK (polyetheretherketone), or Acetal (Delrin®) 12.

[0027] It has been found that by using a cleaning device located outside the housing, the dispensing plate extends no more than 400 mm in the web movement direction when flat and no more than 300 mm in the web movement direction when curved, and the dispensing plate includes a low-friction material coating, a surprising improvement in the cleanliness of the applicator has been achieved.

[0028] This objective is also achieved by an applicator for a machine for producing fiber webs, the applicator being used to apply air to a moving fiber web produced by the machine, the applicator comprising: The housing forms a cavity suitable for receiving air, and is adapted to extend in the width direction of the web transverse to the web movement direction, and has a main body extension of the housing. The housing includes a distribution plate having multiple distribution holes to distribute process air along the width of the web. The applicator includes a retraction actuator assembly, and the housing, when installed in the machine, is adapted to retract away from the web via the retraction actuator assembly.

[0029] Fiber webs can be used for household paper webs.

[0030] This objective is also achieved by an applicator for a paper machine for applying process air to a moving fiber web manufactured by the papermaking process. The applicator includes a housing forming a cavity adapted to receive the process air, the housing being adapted to extend in a web width direction transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate having a plurality of distribution holes for distributing process air along the width of the web. The extension of the distribution plate transverse to the main body extension of the housing is configured such that when the applicator applies process air to the web, the distribution plate extends along the web in the web movement direction by no more than 500 mm, preferably no more than 400 mm, and more preferably no more than 300 mm.

[0031] This objective is also achieved by an applicator for a paper machine for applying process air to a moving fiber web manufactured by the paper machine. The applicator includes a housing forming a cavity adapted to receive the process air, the housing being adapted to extend in a web width direction transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate having a plurality of distribution holes for distributing process air along the width of the web. Each distribution hole has an area of ​​at least 28 mm². 2 Preferably at least 50 mm 2 Preferably at least 78 mm 2 .

[0032] This objective is also achieved by an applicator for a paper machine for applying process air to a moving fiber web manufactured by the paper machine. The applicator includes a housing forming a cavity adapted to receive the process air, the housing being adapted to extend in a web width direction transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate having a plurality of distribution holes for distributing the process air along the width of the web. The distribution plate includes a coating of a low-friction material.

[0033] This objective is also achieved by a machine for producing fiber webs, such as tissue paper or tissue paper, the machine including a process air applicator for applying process air to a moving fiber web produced by the machine. The applicator includes a housing forming a cavity adapted to receive the process air, the housing being adapted to extend in a web width direction transverse to the web movement direction, and having a main body extension of the housing, wherein the housing includes a distribution plate having a plurality of distribution holes for distributing process air along the width of the web. In some embodiments, the applicator includes a retraction actuation assembly, the housing being adapted, when mounted in the machine, to retract away from the web by means of the retraction actuation assembly. Thus, the distribution plate can be kept at a distance from the web, allowing the outer surface of the plate to be cleaned using an external cleaning device. When the cleaning action is complete, the housing can move back to its working position.

[0034] Therefore, the machine may include a drying cylinder, such as a Yankee drying cylinder equipped with a drying hood. Thus, an air inlet in the housing for receiving process air may be connected to or can be connected to an air outlet of the drying hood. In an alternative embodiment, the drying cylinder is the drying cylinder of a through-flow hot air dryer (TAD). Advantageous embodiments of the machine are described below and defined in the claims. Attached Figure Description

[0035] Embodiments of the present invention will now be described with reference to the accompanying drawings, wherein: Figure 1A and Figure 1B A portion of a machine used to produce fiber webs is shown schematically. Figure 2 An applicator for use with the machine of FIG1 is schematically shown, a first embodiment of which is provided with a cleaning device; Figure 3 The applicator of the second embodiment with a cleaning device is schematically shown. Figure 4 An applicator with a cleaning device is schematically shown in a third embodiment. Figure 5 An applicator with a cleaning device in a fourth embodiment is schematically shown. Figure 6 and Figure 7 The arrangement of the cleaning device relative to the applicator is shown schematically. Figure 8 and Figure 9 It schematically shows the relationship with Figure 1B Variations of the applicator used with the machine; and Figures 10 to 13 Different combinations of embodiments are shown. Detailed Implementation

[0036] Figure 1 shows a portion of a machine for manufacturing tissue paper web W. Components of this machine can be found in US9702084B2, which is incorporated herein by reference. The tissue paper web W is first formed in a forming device (e.g., a crescent forming device), where a fiber pulp suspension is injected through a headbox into the gap between two fabrics. Because this is a well-known process, it will not be described further herein. The newly formed tissue paper web is carried forward for pressing and drying. For example, it can be carried forward on the underside of a felt 3, which in many practical embodiments may be one of the two fabrics in which the tissue paper web was initially formed.

[0037] The tissue paper web W can travel at a speed of 1500 m / min to 2500 m / min, or 1700 m / min to 2500 m / min (preferably 1800 m / min to 2400 m / min). An embodiment in which the web W travels at a speed of 1800 m / min to 2000 m / min is conceivable.

[0038] The tissue paper web W is carried by felt and passes through the extended pressing zone N formed between the extended pressing zone unit 2 and the Yankee drying cylinder 1 together with the felt 3.

[0039] The extended pressing unit 2 is preferably a closed roll with a flexible tubular sheath 18 (e.g., a shoe press belt), which may be made of polyurethane or a material containing polyurethane or having similar properties. The extended pressing unit may also have a press body 17, which may be a concave shoe of metal (e.g., steel). The press body 17 may also be an elastically deformable body, and the extended pressing unit may be designed according to, for example, European Patent No. 1678374. The extended pressing unit may also be designed in other ways. For example, the extended pressing unit 2 may be designed in the manner disclosed in EP 2085513, but other known extended pressing units may also be used.

[0040] As shown in Figure 1, the tissue paper web W is carried on the felt 3 through the extending press zone N in such a manner that the tissue paper web W contacts the outer surface 4 of the Yankee dryer cylinder 1. Upon passing through the press zone N, the web W separates from the felt 3 and is conveyed to the Yankee dryer cylinder. The web W and the felt 3 are guided past the suction roller 5 before passing through the extending press zone N. Therefore, the felt 3 contacts the suction roller 5 and is positioned between the tissue paper web W and the suction roller 5. The suction roller 5 is used to partially drain water from the web W. The suction roller 5 has a suction zone 6 through which the felt 3 and the tissue paper web W pass together. An applicator 7 is disposed opposite the suction roller 5 and partially surrounds the suction roller 5, the applicator 7 having an extension around the suction roller such that the applicator 7 covers the entire suction zone 6. Figure 2 As shown, the applicator 7 includes a housing 701 that forms a cavity 702 adapted to receive, for example, process air. The housing 701 is adapted to extend in a web width direction transverse to the direction of movement of the fiber web W, having a main housing direction. The housing 701 also includes a distribution plate 703 provided with a plurality of orifices or distribution holes 704, wherein the distribution plate 703 faces the suction roller 5.

[0041] The diameter of the suction roller 5 can be from 0.50 to 2.00 meters, for example, 1.20 meters. The suction zone can have an axial extension of 3.00 to 12.00 meters, for example, 5.70 meters. The suction zone 6 can extend circumferentially from 45° to 180°, for example, 120° (one-third of the total circumference of the suction roller). Therefore, the total area of ​​the suction zone can be approximately 0.6 to 37.7 m². 2 For example, approximately 7.16m 2 .

[0042] Moist process air can be supplied from the applicator 7 through multiple distribution holes 704 and drawn by the suction roller 5 through the tissue paper web and felt 3. During this time, the tissue paper web W is directly exposed to the applicator 7, so that the moist process air can reach the tissue paper web W without passing through any fabric before reaching the tissue paper web W. Depending on the width of the machine, the total airflow rate from the applicator 7 through the tissue paper web and into the suction roller can typically vary from 0.5 to 3.0 kgDA / s (kg dry air / second).

[0043] The Yankee dryer cylinder 1 is covered by a drying hood 8, which is a Yankee hood with an air heating and distribution system 9. The air heating and distribution system 9 may include one or more heaters 15 and ducts 16 through which hot air is supplied to the drying hood 8, i.e., the Yankee hood. This hot air is blown onto the tissue paper web and helps water evaporate from the tissue paper web.

[0044] The exhaust air from the Yankee hood can then be discharged from the Yankee hood, and the discharged air (exhaust air) is humid and hot. The hot exhaust air can be extracted from the drying hood 8 and supplied to the applicator 7 via duct 10, and used to supply humid hot process air to the applicator 7. The temperature of the discharged humid hot process air is in the range of 100°C to 350°C, preferably in the range of 150°C to 300°C. The moisture content of the humid hot process air is from 150 g water / kg dry air to 1000 g water / kg dry air (i.e., 150 g water per kg of dry air to 1000 g water per kg of dry air). The pressure of the humid hot process air from the drying hood 8 (Yankee hood) is typically close to or slightly higher than standard atmospheric pressure, i.e., approximately 101.325 kPa. When the hot and humid process air reaches the applicator 7, the overpressure of the hot and humid process air can typically be between 0.3 kPa and 2 kPa, but in some cases, an overpressure as high as 3 kPa or even higher can be considered.

[0045] The conduit 10 may be equipped with an inlet fresh air stack 10A with a damper 10B, which is used to control the temperature of the humid, hot air supplied to the applicator. Another method of temperature control is to inject a controlled amount of water or a mixture of water and compressed air, or to inject steam. Typically, the air supplied to the applicator must be in the range of 90°C to 180°C.

[0046] In addition, the duct 10 is equipped with a filter 10C, which is used to purify the air before it is delivered to the applicator. The filter can be a mechanical device, a water-washable device, or any other effective solution.

[0047] Another feature of this system is that the duct 10 is typically equipped with a flow meter 10D, the purpose of which is to continuously measure and (by feeding back to the fan 11) control the flow of air toward the applicator.

[0048] By utilizing the above-described features, the possibility of accidental dust accumulation on the air-blowing surface of the applicator is reduced, facilitating the cleaning process, which is the main objective of this invention. Furthermore, safety is improved through the described features.

[0049] The humid process air is then drawn through the tissue paper web W by suction roller 5. As the humid process air is drawn through the tissue paper web W, the moisture in the air condenses on the tissue paper web W, thereby raising the temperature of the tissue paper web W before it passes through the stretching and pressing zone N. Although the temperature of the tissue paper web can also be raised by completely moisture-free hot air, condensation produces a better heating effect, even if only a portion of the moisture in the humid process air condenses.

[0050] In different configurations of tissue paper machines, the suction roll 5 and the extension press unit 2 are combined in a single component (called the suction press roll). In this configuration ( Figure 1B The applicator 7 is equipped with a flat distribution plate 703 and is positioned immediately in front of the suction press roller, such as... Figure 8 and Figure 9 As shown. The purpose is the same: hot, humid air is supplied from the applicator 7 toward the web W and the felt 3, and then drawn in by the suction press rollers, with the same result.

[0051] To facilitate cleaning of the suction roller 5 and the applicator 7, a retraction actuator assembly can be used ( Figure 1A (Not shown) The applicator 7 is moved away from the suction roller 5 in the direction of arrow A. Optionally, in this case, the applicator can be disconnected from the conduit 10. Optionally, the suction roller can be moved away from the applicator 7. Embodiments in which both the suction roller 5 and the applicator 7 can move away from each other are conceivable.

[0052] In order to improve or maintain the function of the applicator 7 and avoid possible downtime, the applicator 7 is provided with a cleaning device that is designed to remove any particles and debris that may adhere to the dispensing plate 703 and block or clog the dispensing holes 704.

[0053] According to the first embodiment of the cleaning device 705, such as Figure 2 As shown, the cleaning device is located outside the housing 701, at the upper edge of the distribution plate 703, and connected to the fluid source 707 via suitable conduits and pipes 708. The cleaning device 705 is provided with a slotted nozzle 706 that extends substantially along the body of the distribution plate 703. Fluid from the fluid source 707 (e.g., water possibly with added detergent) is delivered to the slotted nozzle 706 via suitable pumping elements and conduits, whereby the fluid flows along the outer surface of the distribution plate 703, thereby removing any particles and debris clogging the distribution orifice 704.

[0054] As another second embodiment and an alternative to cleaning the outer surface of the dispensing plate, it is located inside the housing 701 of the applicator 7, i.e., in the cavity 702. The cleaning device 709 is attached to the dispensing plate and disposed at the upper edge of the dispensing plate 703, as shown below. Figure 3 As shown. The cleaning device 709 is provided with a groove-shaped nozzle 710 that extends substantially along the body of the distribution plate. The nozzle 710 is connected to a fluid source 707 via a suitable conduit or pipe 708.

[0055] The applicator 7 may include a cleaning device 711 in the form of a spray bar, which is disposed outside the housing. For example, as in the third embodiment and as an alternative to an external cleaning device having a slotted external nozzle, the cleaning device 711 in the form of a spray bar may be disposed outside the housing, such as... Figure 4 As shown, the spray bar 711 is designed and arranged such that the fluid ejected from the spray bar will cover the outer surface of the distribution plate 703. The spray bar 711 includes a plurality of nozzle outlets that are positioned along the body of the distribution plate 703 to cover the entire outer surface of the distribution plate 703. Figure 4 As shown, the spray bar 711 can be located above the outer surface of the distribution plate 703 and arranged such that the fluid ejected from the spray bar 711 will impact the upper region of the distribution plate 703 and flow downwards. Using this solution, the spray bar 711 can be attached to a suitable support provided with conduits and pipes for distributing fluid from a fluid source. The spray bar 711 of the applicator 7 can be mounted to the housing 701 or to any other suitable part of the tissue paper manufacturing machine.

[0056] As an alternative to an internal cleaning device with a slotted nozzle, the fourth embodiment includes a cleaning device 712 in the form of a spray bar, which is disposed inside the housing (e.g., Figure 5As shown (i.e., disposed in cavity 702), the spray bar 712 is designed and arranged such that the fluid sprayed from the spray bar 712 will cover the inner surface of the distribution plate 703. In this respect, the spray bar 712 includes a plurality of nozzle outlets 713 which are positioned extending along the body of the distribution plate 703 so as to cover the entire inner surface of the distribution plate 703.

[0057] As an alternative to an external spray bar that is fixed or stationary relative to the outer surface of the distribution plate, the external spray bar can be arranged to be movable relative to the distribution plate. Figure 6 and Figure 7 A feasible solution is shown. As seen on the main body extension of the distribution plate 703, the spray bar 711 has guide elements 714 at both ends. The guide elements 714 are fitted into elongated tracks 715, and the spray bar 711 is connected to a moving element 716. The moving element 716 may include a pneumatically or hydraulically driven piston that, when actuated, can move the spray bar 711 along the tracks 715 to cover the entire outer surface of the distribution plate with fluid, such as... Figure 7 As shown. Figure 6 and Figure 7 As shown, track 715 may have a curvature corresponding to that of distribution plate 703, such that during movement and cleaning with spray bar 711, the nozzle outlet of spray bar 711 is positioned at approximately the same distance relative to distribution plate 703. Track 715 and moving element 716 of applicator 7 may be mounted to housing 701 or to any other suitable part of the tissue paper manufacturing machine. Track may be fixed or may move together with the rest of the applicator, for example, moving away from the suction roller, as described below.

[0058] The above embodiment shows an applicator 7 positioned such that the dispensing plate 703 faces the suction roller 5, whereby the curvature of the dispensing plate 703 approximately corresponds to the curvature of the suction roller 5. However, as Figure 7 As shown, viewed from the web feed direction, the applicator 7' can be positioned "upstream" or before the suction roller 5. In this position, the distribution plate 703' is flat because the fiber web W passing through the applicator 7' is flat. The applicator 7' with the flat distribution plate 703' can have the same type of cleaning device as described above.

[0059] In any of the above embodiments, when a cleaning operation is to be performed, the applicator must be moved away from the suction roller and / or the web W via the retraction actuation assembly 717. The retraction actuation assembly 717 can be designed in various ways to have a suitable mechanism that allows for translational movement of the applicator 7 relative to the suction roller 5 and / or the web W (e.g., Figure 4 (as indicated by the middle arrow T1), or tilting movement (such as...) Figure 8(As indicated by the middle arrow T2). This mechanism can, of course, be designed to perform both translational and tilting movements to change the position of the applicator 7. Those skilled in the art are capable of designing several solutions within their technical capabilities, which will not be discussed in detail herein.

[0060] The above embodiments can be combined in several ways. For example, cleaning can be performed both inside and outside the housing using cleaning devices located inside and outside the housing. In this regard, as Figure 10 As shown, internal cleaning can be performed by a cleaning device 709 with a grooved nozzle 710, and external cleaning can be performed by a cleaning device 705 with a grooved nozzle 706. Alternatively, internal cleaning can be performed using a spray bar 712, such as... Figure 11 As shown. Furthermore, external cleaning can be performed by a fixed or movable spray bar 711. Then it can be used as follows: Figure 12 The grooved nozzle 710 shown or as Figure 13 The spray bar 712 shown performs internal cleaning. In this way, both the inner and outer surfaces of the distribution plate are cleaned.

[0061] It should be understood that the embodiments shown above and in the accompanying drawings are merely non-limiting examples of the present invention and can be modified in various ways within the scope of the patent claims.

Claims

1. An applicator (7) for a machine for producing fiber webs, the applicator being used to apply air to a moving fiber web produced by the machine, the applicator comprising: A housing (701) forming a cavity (702) adapted to receive the air, the housing being adapted to extend in the width direction of the web transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate (703) with a plurality of distribution holes (704) for distributing the air along the width of the web. The applicator includes cleaning devices (705, 709, 711, 712) that extend along the body of the housing and are adapted to apply liquid to the dispensing plate (703).

2. The applicator according to claim 1, wherein the cleaning device (705, 711) is disposed outside the housing (701).

3. The applicator according to any one of the preceding claims, wherein the cleaning device (705, 709) has a groove (706, 710) for liquid application.

4. The applicator according to claim 3, wherein the grooves (706, 710) are disposed at the upper edge of the dispensing plate (703).

5. The applicator according to any one of the preceding claims, wherein the cleaning device (711, 712) includes a spray bar.

6. The applicator according to any one of the preceding claims, wherein the cleaning device (709, 712) is disposed inside the housing (702).

7. The applicator according to any one of claims 1 to 5, wherein the cleaning device (705, 711) is disposed outside the housing (701), wherein the applicator includes an additional cleaning device (709, 712) extending along the body of the housing and adapted to apply liquid to the dispensing plate (703), wherein the additional cleaning device (709, 712) is disposed inside the housing (701).

8. The applicator according to any one of the preceding claims, wherein the applicator includes a retraction actuation assembly (717), and the housing (701), when mounted in the machine, is adapted to retract away from the web by means of the retraction actuation assembly.

9. The applicator according to any one of the preceding claims, wherein the cleaning device (711) is movable relative to the housing so as to move along the dispensing plate.

10. The applicator according to any one of the preceding claims, wherein the extension of the distribution plate (703) transverse to the main body of the housing is configured such that when the applicator (7) applies air to the web, the distribution plate (703) extends along the web in the web moving direction by no more than 500 mm, preferably no more than 400 mm, and preferably no more than 300 mm.

11. The applicator according to claim 10, wherein the extension of the dispensing plate (703) transverse to the body of the housing is configured such that when the applicator (7) applies air to the web, the dispensing plate (703) extends at least 100 mm along the web in the web moving direction.

12. The applicator according to any one of the preceding claims, wherein each of the dispensing holes (704) has an area of ​​at least 28 mm. 2 Preferably at least 50 mm 2 Preferably at least 78 mm 2 .

13. The applicator according to any one of the preceding claims, wherein the dispensing plate (703) has a plurality of dispensing holes (704) arranged in a grid pattern to dispense the air along the width of the web and along the length of the web.

14. The applicator according to any one of the preceding claims, wherein the dispensing plate (703) comprises a coating of a low-friction material.

15. The applicator according to any one of the preceding claims, wherein the fiber web is in the form of a tissue paper web (W).

16. The applicator according to claims 2 and 8, wherein the dispensing plate (703) is curved or flat.

17. The applicator according to any one of the preceding claims, wherein the applicator is located upstream of the suction roller of the machine when viewed from the feed direction of the web.

18. An applicator (7) for a paper machine for applying process air to a moving fiber web manufactured by the machine, said applicator comprising: A housing (701) forming a cavity adapted to receive the process air, the housing being adapted to extend in the width direction transverse to the web movement direction and having a main body extension of the housing. The housing includes a distribution plate (703) with a plurality of distribution holes (704) for distributing the process air along the width of the web. The extension of the distribution plate (703) transverse to the main body of the housing is configured such that when the applicator (7) applies the process air to the web, the distribution plate (703) extends along the web in the web moving direction by no more than 500 mm, preferably no more than 400 mm, and preferably no more than 300 mm.

19. An applicator (7) for a paper machine for applying process air to a moving fiber web manufactured by the machine, said applicator comprising: A housing (701) forming a cavity adapted to receive the process air, the housing being adapted to extend in the width direction of the web transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate (703) with a plurality of distribution holes (704) for distributing the process air along the width of the web. The area of ​​each of the dispensing holes (704) is at least 28 mm. 2 Preferably at least 50 mm 2 Preferably at least 78mm 2 .

20. An applicator (7) for a paper machine for applying process air to a moving fiber web manufactured by the machine, said applicator comprising: A housing (701) forming a cavity adapted to receive the process air, the housing being adapted to extend in the width direction of the web transverse to the web movement direction, and having a main body extension of the housing. The housing includes a distribution plate (703) with a plurality of distribution holes (704) for distributing the process air along the width of the web. The distribution plate (703) therein includes a coating of low-friction material.

21. The applicator according to any one of claims 18 to 20, wherein the applicator (7) includes a retraction actuation assembly (717), and the housing (701), when mounted in the machine, is adapted to retract away from the web by means of the retraction actuation assembly.

22. A machine for producing fiber webs, such as tissue paper, for example, thin sheets of paper, the machine comprising an applicator according to any one of the preceding claims.

23. The machine according to claim 22, wherein the machine includes a drying cylinder (1), such as a Yankee drying cylinder, the drying cylinder being equipped with a drying hood (8), and wherein an air inlet for receiving process air in the housing (701) is connected via a conduit (10) to or is connectable to an air outlet of the drying hood.

24. The machine according to claim 23, wherein the conduit (10) is equipped with means (10A, 10B) for controlling the temperature of the humid process air delivered to the applicator.

25. The machine according to claim 24, wherein the means for controlling the temperature is a fresh air manifold (10A) with a damper (10B).

26. The machine of claim 24, wherein the means for controlling the temperature is a water or water / air compressor injector.

27. The machine according to claim 24, wherein the device for controlling the temperature is a steam ejector.

28. The machine according to any one of claims 22 to 27, wherein the conduit (10) is equipped with a filter (10C) for purifying the air before it is delivered to the applicator.

29. The machine according to claim 28, wherein the filter (10C) is a mechanical filter.

30. The machine according to claim 28, wherein the filter (10C) is a water filter.

31. The machine according to any one of claims 23 to 30, wherein the conduit (10) is equipped with a flow meter (10D) for continuously measuring and controlling the air flowing toward the applicator.

32. A machine for producing tissue paper fiber webs, comprising an applicator (7) for applying process air to a moving fiber web produced by said machine, said applicator (7) comprising: A housing (701) forming a cavity (702) adapted to receive the process air, the housing being adapted to extend in the width direction of the web transverse to the web movement direction, and having a main body extension of the housing. The housing (701) includes a distribution plate (703) with a plurality of distribution holes (704) for distributing the process air along the width of the web, and The retraction actuator (717), when the housing (701) is installed in the machine, is adapted to retract away from the web by means of the retraction actuator, so that the distribution plate (703) can be kept at a certain distance from the web, thereby allowing the outer surface of the distribution plate (703) to be cleaned using external cleaning devices (705, 711). The machine includes: The drying cylinder (1), for example a Yankee drying cylinder, is equipped with a drying hood (8), and wherein an air inlet for receiving the process air in the housing (701) is connected via a conduit (10) to or can be connected to an air outlet of the drying hood (8).

33. The machine according to any one of claims 22 to 32, comprising a suction roller, wherein the applicator is located upstream of the suction roller when viewed from the feed direction of the web.

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