Patent Description:
The invention generally relates to cleaning head systems, and relates in particular to cleaning head systems for use in traversing shower systems.

Traversing shower systems may be used in a variety of industrial applications, including for example, papermaking, tissue making, fibre mat processing (e.g., glass fibre mat), as well as many further applications involving fabrics, clothing, and other belt applications, or rolls in similar industries and applications.

<FIG> shows a traversing shower beam <NUM> with a cleaning head <NUM>. As a material <NUM>, e.g., fabric, belt, mat or roll (shown in <FIG>) moves under the beam <NUM> in a machine direction, the cleaning head <NUM> traverses the beam in the cross-machine direction to clean the surface of the material <NUM>. <FIG> shows a broken away portion of the cleaning head <NUM> that provides to the material high pressure water at an angle of about <NUM> degrees (as shown at <NUM>) as well as forced air as shown at <NUM> and <NUM> at more shallow opposing angles, as well as at <NUM> at an angle more normal to the surface of the material. Vacuum in provided via channels <NUM>, <NUM>, <NUM>. The cleaning head applies the pressurized water and air, as well as the vacuum to loosen and remove debris from the material.

Published application <CIT> describes a cleaning head used in a traversing shower system with a plurality of directional cleaning nozzles which supply fluid to a work surface, and arranged so no two fluid streams cross.

Published application <CIT> describes a device and a method for cleaning a material web. Cleaning is achieved by a device comprising cleaning agent nozzles for spraying a cleaning agent in order to clean a material web, said cleaning agent nozzles being disposed on a first side of the material web, and gas nozzles for spraying a gas optionally the device is configured for generating a vacuum on a first side of the material web. At least the gas nozzles are arranged relative to the material web on the first side of the material web in such a way that the gas jets penetrate the material web. An area that is located opposite the first side of the material web on a second side of the material web is designed such that at least the gas jets which penetrate the material web can be discharged from the material web into said opposite area. It further discloses a method for reducing or preventing spreading of a spray mist.

There remains a need however for more efficient and more economical cleaning systems for use in traversing shower systems.

Some optional features are defined by the dependent claims.

In accordance with various aspects, the invention provides an improved cleaning head for a traversing shower system, and a method of using a cleaning head in a traversing shower system, that is used for cleaning machine materials (e.g., fabrics/clothing/belts) in for example, paper, tissue, non-woven, glass fibre mat etc. applications. Systems and methods of various aspects of the invention involve the use of fluid nozzles in particular directions and air doctor systems together with an improved vacuum flow passage for evacuation of water and contaminants, allowing for better cleaning result and machine clothing with less residual moisture remaining after the cleaning process, providing improved dryness.

A cleaning head in accordance with various aspects of the present invention is shown at <NUM>, and may be mounted on a traversing beam <NUM> for movement above a roll material <NUM> being cleaned as shown in <FIG>. The cleaning head <NUM> may include a central unit <NUM> and an external unit <NUM> mounted external to the central unit <NUM> as further shown in <FIG>. Liquid may be provided at a fluid port <NUM>, and air may be provided, at least in part, at a gas port <NUM>, while vacuum may be provided at a vacuum chamber opening <NUM> (shown in <FIG>). The fluid sources (e.g., water/chemicals and air/chemicals) as well as the vacuum source, may be provided via direct couplings or via couplings through the traversing beam <NUM>.

<FIG> shows a top view and <FIG> shows a bottom view of the cleaning head <NUM> of <FIG>. The cleaning head <NUM> in accordance with aspects of the invention includes a fluid applicator assembly <NUM> for providing fluid (e.g., liquid such as water or chemicals or a mix or water and chemicals) to a work surface <NUM>. The fluid applicator assembly <NUM> includes a fluid applicator head <NUM> that includes a plurality of nozzle apertures, which are discussed in more detail below. The fluid applicator head <NUM> is coupled via the conduit <NUM> to the fluid applicator source as noted above. Gas under pressure is provided to a gas applicator assembly that includes a gas intake port <NUM> (shown in <FIG>) and a central unit air knife assembly <NUM> that includes one or more rows of gas nozzles. The external unit <NUM> (e.g., knife edge unit) also includes a plurality of nozzle apertures (discussed in more detail below with reference to <FIG>), and is mounted to the central unit <NUM> by an arm <NUM>. The arm <NUM> positions the external unit proximate (e.g., above) the material either on a roll or as the material is leaving the roll in the Machine Direction (MD). Gas under pressure is also provided to one or more ports <NUM>, <NUM> of the external unit <NUM> from a source of pressurized gas.

With reference to <FIG> (showing enlarged top and bottom views of the central unit), the cleaning head <NUM> also includes the forced air conduit <NUM> coupled to a gas applicator source (including one or more rows of nozzles) for providing pressurized air to the work surface, as well as a vacuum source for providing vacuum to the work surface via vacuum passage <NUM> within the central unit <NUM>. The fluid applicator head <NUM> of the central unit <NUM> includes a plurality of directional nozzles as discussed in further detail below. Pressurized air is provided to the work surface by a plurality of air nozzles <NUM> (e.g., in the form of an air knife). The cleaning head <NUM> provides an improvement over the prior cleaning heads as it has a new concept of nozzle directions and air doctor system together with an improved vacuum flow passage for evacuation of water and contaminants, allowing a better cleaning result and almost totally dry machine clothing.

Moreover, cleaning heads in accordance with various aspects will help to improve the machine runnability and prevent wet streaks in the end product. Such cleaning heads may be used in many other manufacturing processes where a contamination needs to be removed from any machine clothing, belt or roll. The cleaning head of various aspects of the invention provides a significantly different head with an optimized vacuum chamber and flow pattern together with an improved nozzle body and air knife in accordance with various aspects of the invention.

The inside shape of the cleaning head is designed to avoid dead spots and corners in order to achieve more uniform flow velocity throughout the flow channel. This also reduces turbulence and causes less contamination to stick on the inside surfaces of the cleaning head chamber. The transition from cleaning head vacuum to vacuum pipe is also virtually direct, providing straight vacuum flow in the cleaning head of aspects of the invention. The cleaning head <NUM> also includes an extension arm <NUM> onto which is provided an external V-shaped air knife unit <NUM>.

<FIG> shows a sectional view of the central unit of <FIG> taken along line <NUM>-<NUM> thereof. Fluid (e.g., water or water-based solutions) is provided via the fluid applicator head <NUM> of the fluid applicator assembly <NUM> to a work surface <NUM> as shown at <NUM> contacting the work surface at a concentrated area <NUM>. The fluid applicator head <NUM> is positioned within the vacuum passage <NUM>, and slightly above (e.g., <NUM>, <NUM>, <NUM> or up to <NUM> above the material). The positioning of the fluid applicator head <NUM> with respect to the work surface and the vacuum passage permits more efficient cleaning, particularly when combined with the application of air.

In particular, air is provided (shown at <NUM> in <FIG>) by air knife <NUM> using nozzles <NUM>, <NUM>, <NUM> as shown in <FIG>. The plurality of nozzles <NUM> may be provided as directed perpendicular to the surface being cleaned, while the end nozzles <NUM>, <NUM> may be angles that are directed inward toward the air flow from the nozzles <NUM> (as shown diagrammatically in <FIG>). Additional fluid (e.g., air) is provided by a source to the plurality of air knife nozzles <NUM> as shown at <NUM>. The material <NUM> may be provided on a cylinder roll <NUM>, and may leave the roll (as shown at <NUM>) after moving past the traversing shower head <NUM>. The external unit <NUM> (discussed above with reference to <FIG>) that is mounted on arm <NUM> may be positioned with either over the work surface <NUM> while the material is still on the roll <NUM>, may be positioned over the work surface as the material leaves the roll (as shown at <NUM>), or may be positioned over the work surface after the material has left the roll (as shown at <NUM>), again, above the work surface of the material.

The fluid applicator assembly head <NUM> on which the directional fluid nozzles are provided is designed to optimize the impact of energy to the cleaning surface. Each spot of the fabric will be cleaned from all directions. The jet impact area is minimized during each moment of cleaning in order to keep the wetted area as small as possible. This increases the removal of water and dirt after cleaning. The fluid conduit body is also designed to reduce losses of vacuum flow and preventing the tendency to build up contaminants. The end of the fluid conduit body designed with angled surfaces to achieve the optimum nozzle angles and nozzle positions as shown in <FIG>.

The nozzles of the fluid applicator head <NUM> are designed to provide fluid (e.g., water) onto the work surface along a small section in the Cross Machine Direction (CMD), where the jet nozzles provide fluid from different angular directions. The impingement points on the work surface are shown at <NUM>, <NUM>, <NUM>, <NUM>, <NUM> in <FIG>, and the varied angular impingement is provided by directional nozzles <NUM>, <NUM>, <NUM>, <NUM>, <NUM> (shown in <FIG>). The fluid applicator head <NUM> extends into the vacuum passage <NUM>, and may be centrally located within the passage <NUM>, a short distance away from the work surface as noted above. The underside of the fluid applicator head <NUM> includes nozzle apertures <NUM>, <NUM>, <NUM>, <NUM>, <NUM> as shown in <FIG>.

With reference to <FIG>, the nozzle apertures <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are associated with nozzles <NUM>, <NUM>, <NUM>, <NUM>, <NUM> respectively, and the nozzles are positioned within the fluid applicator head <NUM> at different angles as follows. The nozzle <NUM> is positioned perpendicular to the work surface. The nozzle <NUM> is directed in a machine direction, and the nozzle <NUM> is directed in a direction opposite the machine direction. The nozzle <NUM> is directed in a first cross-machine direction, and the nozzle <NUM> is directed in a second cross-machine direction that is opposite the first cross-machine direction. The nozzle apertures <NUM>, <NUM>, <NUM>, <NUM>, <NUM> are positioned strategically to provide the desired impingement pattern on the work surface. The multi-directional impingement on the work surface is discussed in more detail below with reference to <FIG>.

The cleaning width is kept to a minimum in the cross machine direction on the work surface (e.g., <NUM>, <NUM> or <NUM>), and an objective is to clean each individual element (e.g., yarn) in the material from several sides in order to remove even hidden dirt. <FIG> shows the fluid applicator assembly <NUM> including the fluid applicator head <NUM> positioned above the work surface <NUM> by a distance d<NUM>, of for example, <NUM>, <NUM> or <NUM>, <NUM>, <NUM> or <NUM> (e.g., ≤ <NUM>). The angles of impingement provided by nozzle apertures <NUM>, <NUM> (shown at β in <FIG>) may be selectable between <NUM>°-<NUM>° in the machine direction. With reference to <FIG>, the angles of impingement provided by nozzle apertures <NUM>, <NUM> (shown at α) may be selectable between <NUM>°-<NUM>° in cross machine direction respectively, depending on machine clothing design. The range of the cleaning line in the machine direction is shown at d<NUM>, and may be, for example, <NUM>, <NUM> or <NUM> on the work surface. In accordance with an aspect, a minimum of (<NUM>) nozzles is required to achieve the <NUM>-directional cleaning jet geometry described above, however additional nozzles could be employed as required for a particular cleaning application (e.g., multiple nozzles in one or more of the <NUM>-directional planes).

As noted above, the fluid nozzles <NUM>, <NUM>, <NUM>, <NUM>, <NUM> provide directional fluid discharge at apertures <NUM>, <NUM>, <NUM>, <NUM>, <NUM> respectively at mutually different angular directions to provide a desired impingement pattern on the work surface in accordance with an aspect of the present invention. In particular, the discharge from the nozzle <NUM> at aperture <NUM> impinges the work surface at location <NUM> in a first direction as shown in <FIG> The discharge from the nozzle <NUM> at aperture <NUM> impinges the work surface at location <NUM> in a second direction that is slightly offset from (by d<NUM> + d<NUM>) and opposite the first direction. The discharge from the nozzle <NUM> at aperture <NUM> impinges the work surface at a location <NUM> in a third direction, and the discharge from the nozzle <NUM> at aperture <NUM> impinges the work surface at a location <NUM> in a fourth direction that is offset from (by d<NUM> + d<NUM>) and opposite the third direction. The discharge from the nozzle <NUM> at the aperture <NUM> impinges the work surface at a location <NUM> that is perpendicular (normal) to the surface of the work surface. The location <NUM> is offset from the location <NUM> by d<NUM>, and offset from the location <NUM> by d<NUM>. <FIG> shows an enlarged view of the aperture <NUM> (shown at <NUM>) and impingement point <NUM>, showing the direction of impingement. Jet or fan nozzles can be used for the nozzles <NUM>, <NUM>, <NUM>, <NUM>, <NUM> e.g., with an orifice diameter in the range of <NUM> - <NUM>. The nozzle supply pressure may be typically be in the <NUM>-<NUM> bar range.

The power of a water jet is dependent on stand-off distance; and also impacted by, among other things, the air knife and vacuum operating properties and geometry. The cleaning head of various aspects of the invention is designed for a stand-off distance of ≤ <NUM> from each jet to the surface of the fabric or object which is to be cleaned. This generates the maximum amount of the applied energy for cleaning. In this configuration, the jet will not be deflected or diverted, or the energy reduced by the vacuum or air knife. The fluid applicator assembly is designed to prevent the individual water jets from crossing over each other, independent of the distance between the nozzle body and machine clothing. Use of variations of nozzle types are possible.

As noted above with reference to <FIG>, the cleaning head <NUM> includes an external air knife unit <NUM>, and with reference to <FIG>, the unit <NUM> includes a first plurality of apertures <NUM> that form a fan shape in the machine direction (as shown at <NUM>), and a second plurality of apertures <NUM> that form a stem shape in the machine direction (as shown at <NUM>). Together, the apertures <NUM>, <NUM> form a generally Y-shaped pattern of apertures. In particular, the individual air knife apertures are specifically arranged in a Y formation (see <FIG>) in accordance with an aspect of the invention, with the run direction of the machine from the bottom of the "Y-shape" to the top. The second plurality of apertures <NUM> may include two offset and parallel rows of apertures (the second plurality of apertures <NUM>) that are aligned to the cleaned width of the central unit, and may be designed to blow off most of the water. The following triangular/fan shape (the first plurality of apertures <NUM>) may be designed to blow out any residual water and also to distribute the residual water by the air jet across the width. The number, angle, and diameter of holes in the air knife unit are optimized depending on machine and clothing type. The holes may be angled in CMD and MD if desired for particular applications, similar to the apertures of the internal air doctor <NUM>.

<FIG> shows a cleaning head in accordance with another aspect of the invention that includes central unit <NUM>' with an internal vacuum passage <NUM>' and a fluid applicator assembly <NUM>' therein, coupling a fluid applicator head <NUM>° to a fluid source via coupling <NUM>'. The central unit <NUM>° also includes an air doctor assembly <NUM>' with nozzles <NUM>', <NUM>' and <NUM>' (with a fan angle set range of α<NUM>) that are coupled to a source of pressurized air at coupling <NUM>'. The components function as discussed above with reference to <FIG>, and <FIG> shows the relative angles of the nozzles <NUM>', <NUM>', <NUM>. The central unit <NUM>' of <FIG> however, further includes a second central air knife assembly including nozzles <NUM>" with a fan angle set range of α<NUM> that may be equal and oppositely oriented with respect to the fan angle set range of α<NUM>.

The cleaning head <NUM>' may be further fitted with lubrication nozzles <NUM> (further shown in <FIG> and <FIG>) to prevent adhesion of removed dirt from the walls of the vacuum passage. The internal air knife <NUM>' is equipped with air opening holes at the outlet of the head, and is adjustable in the machine direction, allowing different angles to be set in MD (machine direction) and against MD. Again, the apertures (<NUM>', <NUM>') at the edges of the air knife <NUM>' are angled (shown in <FIG>) and the apertures <NUM>' are straight in CMD (cross machine direction). With reference again to <FIG>, a second air knife assembly including apertures <NUM>'' in the cleaning head inlet may optionally be provided (shown at <NUM>"), and the design of the inlet air knife <NUM>'' may be the same as the air knife <NUM>' at the outlet, which is similar to that discussed above with reference to <FIG>.

In accordance with further aspects, and with reference to <FIG>, a central unit <NUM>" of a cleaning head may include a further arrangement and sizing of apertures at a fluid applicator head <NUM>" of a fluid applicator assembly <NUM>'', as well as a central air knife doctor assembly <NUM>'' that includes two rows of air nozzles.

Claim 1:
A cleaning head (<NUM>) for use in a traversing shower system, said cleaning head comprising a plurality of directional fluid nozzles (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) for discharging a fluid onto a working surface (<NUM>), each of which is provided along a different direction toward the work surface such that no two directions cross one another between the cleaning head and the working surface,
wherein the plurality of directional fluid nozzles (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) includes a first plurality of directional fluid nozzles (<NUM>, <NUM>) directed in a machine direction of the working surface, a second plurality of directional fluid nozzles (<NUM>, <NUM>) directed in a cross-machine direction of the working surface, and a directional fluid nozzle (<NUM>) that is directed normal to the working surface,
wherein the cleaning head further comprises a central unit (<NUM>), the central unit including a central aperture (<NUM>) through which a vacuum is provided to draw liquid and debris from the working surface and at least one forced air nozzle (<NUM>) for providing forced air onto the working surface proximate the central aperture (<NUM>); and
wherein the cleaning head further comprises a fluid applicator assembly (<NUM>) that extends into the central aperture (<NUM>), said fluid applicator assembly including the plurality of directional fluid nozzles (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) for discharging the fluid onto the working surface from at least two different directions, wherein the fluid discharged onto the working surface is a liquid.