Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B13/00—Machines or plants for applying liquids or other fluent materials to surfaces of objects or other work by spraying, not covered by groups B05B1/00 - B05B11/00
  • B05B13/02—Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work
  • B05B13/04—Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work the spray heads being moved during spraying operation
  • B05B13/0442—Installation or apparatus for applying liquid or other fluent material to separate articles rotated during spraying operation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
  • B05B12/16—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling the spray area
  • B05B12/32—Shielding elements, i.e. elements preventing overspray from reaching areas other than the object to be sprayed
  • B05B12/36—Side shields, i.e. shields extending in a direction substantially parallel to the spray jet
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
  • C23C4/14—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying for coating elongate material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/16—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating or cooling the material to be sprayed
  • B05B7/22—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating or cooling the material to be sprayed electrically, magnetically or electromagnetically, e.g. by arc
  • B05B7/222—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating or cooling the material to be sprayed electrically, magnetically or electromagnetically, e.g. by arc using an arc
  • B05B7/226—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas incorporating means for heating or cooling the material to be sprayed electrically, magnetically or electromagnetically, e.g. by arc using an arc the material being originally a particulate material

Definitions

• a coating material is deposited on the paper support in order to give the paper certain properties such as the smooth and resistant surface state.
• One of the members is made up of composite blades forming a contact doctor blade for spreading the coating material in relative movement 0 relative to said blade.
• Another member is constituted by rods or bars for transferring coating material to the paper support, said rods or bars being commonly called rod (s) in the technical sector considered.
• the coating bars may have a smooth or fluted appearance on the surface.
• the coating bars When the coating bars are smooth, they serve to wring out the coating material when the latter is on the transfer cylinder before said coating material is transferred to the paper support. 0 When the coating bars are fluted, they constitute a means for metering and transferring the coating material onto the paper support, owing to the fact that the coating bars pass through a container of coating material so as to fill the splines with said coating material before transferring it to the paper support which passes over a cylinder.
• a first problem to be solved relates to the surface condition which must be such that the transfer of the coating material to the paper must take place in a controlled and homogeneous manner, regardless of the type of coating bar, smooth or grooved.
• a second problem relates to the manufacture of the coating bar. Indeed, the current trend is to use sleeping bars of 5 larger and larger, the length being able to reach 10 meters and more.
• a third problem concerns the production of the coating on the coating bar. When the coating is carried out by thermal spraying, it is necessary to drive the coating bar in rotation during the entire deposition operation. However, one of the difficulties encountered is the setting in vibration of the coating bar which causes for example a rebound of the particles which is all the more important as the vibration is high. One of the consequences of such a rebound of the particles projected onto the coating bar is the formation of a non-uniform coating over the entire length of the coating bar.
• a first solution recommended by the present invention is to hold the coating bar at its two ends on a frame and to center it relative to the jaws of said frame.
• the sleeping bar When the sleeping bar is very long, it may cause a deflection in the center of the sleeping bar.
• An object of the present invention is a method of manufacturing a sleeping bar, of the type consisting in holding the two ends of said bar on end supports of a frame, one of the ends being held fixed, and in driving in rotation said bar and which is characterized in that it further consists in stretching said bar during the projection of a coating on said bar, the stretching of said bar corresponding to an elongation of about 0.2 to 0.001% in static.
• the coating bar which is coated is kept straight during the projection of said coating.
• the coating bar is made of ferromagnetic material and, more particularly, a chrome steel.
• the device for implementing the method of manufacturing the coating bar is of the type comprising a frame on which said coating bar is mounted, at least one motor driving said bar in variable and adjustable rotation. coating, means for thermal projection of a coating, characterized in that it further comprises means for pulling one end of said bar, the other end being held fixed, said pulling being carried out during rotation of said coating bar and during thermal spraying of said coating. The simultaneous adjustment of rotation and traction allows stabilization of the bar.
• the device comprises means for centering and holding at least part of the coating bar, said means being, for example, constituted by a bearing which can be magnetic, fluid or mechanical .
• An advantage of the present invention lies in the fact that a perfectly stable and uniform coating bar is obtained which allows effective drying of the coating material before it is transferred to the paper support when it is smooth. In the case of corrugated bars, the dosage is better carried out due to the nature of the coating.
• the coating bar has a much longer lifespan, which reduces the number of changes and therefore a considerable reduction in the cost of manufacturing coated paper.
• FIG. 1 is a schematic representation of an embodiment of the device according to the invention
• FIG. 2 is a schematic representation of a side view of the device in FIG. 1,
• FIG. 3 is a schematic representation of a front view of the device in FIG. 1,
• FIG. 4 is a schematic representation of certain mechanical parts of the device in FIG. 1.
• the method of manufacturing a coating bar 1 consists in mounting said bar at its two ends, one end, for example the end 2, being kept fixed on a support 3, while the other end 4 is mounted on a mobile support 5.
• the mobile support 5 is moved so as to tension said coating bar 1, with the force necessary for the desired elongation, during the thermal projection of a coating and during the rotation of said coating bar 1.
• the rotation of the coating bar 1 is ensured by a variable speed motor 6.
• the traction carried out on the end 4, by appropriate means, like those which will be described later, is such that the elongation of said coating bar corresponds to an elongation of between 0.2 and 0.001%.
• the bar In order to considerably reduce the vibrations of said bar 1 during rotation, the bar is kept rectilinear in the zone where the thermal spraying of the coating is carried out, so as to produce a uniform coating in said zone.
• the coating bar 1 is perfectly centered during the thermal projection of the coating in addition to its rectilinear maintenance, a perfectly homogeneous coating bar is obtained over its entire length and whatever the latter.
• it is possible to manufacture coating bars having a length greater than 10 m for example and provided with a coating of constant thickness and without any mark.
• the traction ceases, for example, after the coating is placed on the entire surface of the coating bar, there is compression of said coating, in the direction opposite to the direction of traction. This compression of the coating increases its hardness and greatly reduces the risk of the appearance of cracks.
• FIGS. 1 to 4 A device for implementing the process which has just been described is shown in FIGS. 1 to 4.
• the device comprises a rigid frame 10 on which are mounted a variable speed motor 6 for driving in rotation the coating bar 1, two end supports 3 and 5 in which the ends 2 and 4 of said bar are arranged.
• the device comprises means for thermal spraying 11 of a powder which, after spraying on the bar 1, constitutes the coating.
• the thermal spraying means 11 are constituted for example by a plasma torch 12 which is mounted on a carriage 13 which is driven in translation on the frame 10, using a motor not shown, the displacement means being able, by example, be constituted by a transmission belt.
• the support 3 receives the end 2 of the rod 1 and maintains said end 2 fixed.
• the means for clamping and immobilizing the end 2 can be constituted by jaws, known per se.
• the other end 4 of the bar 1 is mounted in the support 5 which is secured to a beam 14 mounted transversely on the frame 10 and which is in turn secured to two rods 15 of two jacks 16.
• the jacks 16 are supplied in hydraulic and / or pneumatic energy in a manner known per se and put in tension the bar 1, so that the latter is stretched, to the right in FIG. 4, and produce a traction corresponding to an elongation of the bar of approximately 0.2 to 0.001%.
• the device also comprises means for holding and centering the bar 1, so as to keep said bar straight or horizontal or substantially horizontal during the various phases of thermal spraying of the coating, that is to say, at the various positions of the plasma torch 12 along said bar 1.
• these means of holding and centering can be constituted by a magnetic bearing 17 which is crossed by the bar 1 and which creates a magnetic field sufficient to prevent the vibration and bending of the bar 1.
• the magnetic bearing 17 whose structure is well known specialists, is moved at the same time as the plasma torch 12 so that in each projection zone materialized by a rectangle 18 in Figure 1, the bar 1 is maintained and centered.
• Other devices such as fluid bearings or mechanical bearings can be used successfully.
• the plasma torch 12 comprises a powder injector 19 which is supplied with powder from a source not shown.
• the flame 20 projects the powder onto the substrate to be coated, constituted in this case by the bar 1 driven in rotation.
• the device according to the invention comprises an adjustable protective cover 21, in the form of a cone open at the top, so as to focus the projection only on the part of the bar to be coated.
• one or more nozzles 22 are provided which spray CO 2 on the bar, opposite the flame and more concretely at the base of the protective cover 21.
• the jacks 16 are released so that said bar retracts in a direction opposite to the direction of traction, said retraction causing compression of the coating which improves the cohesion of said coating and which prevents the formation of cracks.
• the method and the device according to the invention can be implemented for the manufacture of smooth or grooved coating bars.
• grooved bars it is advantageous to produce grooves in which two consecutive groove bottoms are separated by 0.35 mm and whose radius of curvature is approximately 0.06 mm.
• the lateral sides of each groove are preferably inclined at 45 °, ' the height of the groove preferably being equal to 0.11 mm.
• Such grooves with a uniform and homogeneous coating of the bar allow a more precise dosage of the coating material on the paper.
• the covering consists of a ceramic and the protection and limitation means (21) consist of lateral and adjustable covers, situated on either side of the coating bar (1 ).

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Plasma & Fusion (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Coating By Spraying Or Casting (AREA)
• Coating Apparatus (AREA)
• Paper (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9512692

Family Applications (1)

Country Status (7)

Cited By (2)

Families Citing this family (5)

Family Cites Families (7)

• 1997
  • 1997-10-27 FR FR9713449A patent/FR2770156B1/fr not_active Expired - Fee Related
• 1998
  • 1998-10-27 WO PCT/FR1998/002300 patent/WO1999022041A1/fr not_active Ceased
  • 1998-10-27 DE DE69801287T patent/DE69801287T2/de not_active Expired - Fee Related
  • 1998-10-27 EP EP98952800A patent/EP1027471B1/de not_active Expired - Lifetime
  • 1998-10-27 AT AT98952800T patent/ATE203785T1/de not_active IP Right Cessation
  • 1998-10-27 JP JP2000518127A patent/JP2001521064A/ja active Pending
• 2001
  • 2001-11-05 US US10/011,460 patent/US6761768B2/en not_active Expired - Fee Related

Non-Patent Citations (1)

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