AU660734B2

AU660734B2 - An arrangement for painting an extended object moving continuously in its longitudinal direction

Info

Publication number: AU660734B2
Application number: AU28645/92A
Authority: AU
Inventors: Anders Lindblad
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-10-17
Filing date: 1992-09-09
Publication date: 1995-07-06
Anticipated expiration: 2012-09-09
Also published as: SE9103019L; WO1993007968A1; JPH07500768A; ATE156040T1; MY108047A; SE9103019D0; EP0608323A1; CA2120530A1; DK0608323T3; SE469212B; RU2099153C1; RU94020986A; ES2108135T3; NZ244325A; EP0608323B1; DE69221310D1; CA2120530C; BR9206642A; JP3410735B2; AU2864592A

Abstract

To obtain paint on all sides of a strip, painting must be performed in two stages since the strip must rest on a surface while being painted. This is avoided if moving strips are guided in a manner allowing them to be free from mechanical support from the start of painting until they have passed a drying unit (11), after which they can rest on a support surface without the paint being damaged.

Description

OPI DATE 21/05/93 APPLN, ID 28645/92 li 11 iiI iiIIIIN AOJP DATE 22/07/93 PCT NUMBSR PCT/SE92/00620 IliiI iiiiIIl AU9228645 F(51) International Patent Classification f(11) International Publication Number: WXO 93/079681 13/02, BO5C)13/00 Al (43) International Publication Date: 29 April 1993 (29,04.93) (21) International Application Number: PCT/SE92,/00620 Published (22) International Filing Date: 9 Septenmber 1992 (09.09.92) Wt nrainlsac eot Priority data;6 7 9103019-7 17 October 1991 10.9 1) SE (7 1)(72) Applicant and Inventor: L1IN D BLA D, Anders [S E/S E] Skrantabacken 16D, S-691 42 Karlskoga (SE).

Agent: LAUTIMANN, Kurt; Box 245, S-691 25 Karlskoga (S E), (81) Designated States: AU, BG. BR, CA, CS, Fl, HU, JP, KR, NO, PL, RO, RU, SE, US, European pattent (AT, BE, C H, D E, D K, E S, F R, G B, G R, I E, I T, L U, M C, N L, S E), (54) Title: AN ARRAXNGEMENT FOR PAINTING AN EXTENDED OBJECT MOVING CONTINUOUSLY IN ITS LON- GITUDINAL DIRECTIONI (57) Abstract To obtain paint on all sides of a strip, painting must be performed in two stages since the strip must rest on a surface while being painted. This is avoided if moving strips are guided in a manner allowing them to be free from mechanical support from the start of painting until they have passed a drying unit after which they can rest on a support surface without the paint being damaged.

'r 't 1 AN ARRANGEMENT FOR PAINTING AN EXTENDED OBJECT MOVING CONTINUOUSLY IN ITS LONGITUDINAL DIRECTION The present invention relates to an arrangement for painting all sides of extended objects, said objects possibly having different cross sections. Such objects have previously been painted by being placed on a conveyor and painted on all sides except the side in contact with the conveyor. The painted objects were then dried by means of ultraviolet radiation, for instance. When dry, the objects were turned over and painted on the remaining, unpainted side.

The disadvantage of this method is that it takes too long to paint extended objects on all sides, and also that special apparatus is needed to turn the objects ready for painting on the surface initially serving as contact surface.

Another disadvantage is that paint containing solvent is used, which is unsatisfactory from the environmental aspect.

*r C an The present invention provides an arrangement for painting all sides of an extended object such as rod, strip or the like, said object consisting of optional rigid material such as wood, wood-pump board or the like, and moving continuously in longitudinal direction, including a closed container, its lower part containing a mixture of binder, monomer and pigment, a passage arrangement for the extended object 20 allowing it to pass through the container above the surface of the mixture, a go painting arrangement such as vacuum arrangement so that the extended object within the container becomes coated with a layer of the mixture, guide means such that the coated object is guided in such a way that it remains freely suspended until a drying unit has dried the object from below and it can come into contact with a support surface, and a second drying unit drying the object from above.

The object of the present invention is to increase the production rate during painting. This is enabled by painting on all sides, the part to be painted and dried being freely suspended and not in contact with any support surface.

Guiding the part behind the portion being painted allows the latter to remain T freely suspended during painting and while being transported for drying. The 1 a drying process can be shortened if very quick-drying paint is used, such as a mixture of binder and monomers that may also contain colour pigment. such a mixture dries extremely quickly if it is subjected to radiation energy so that polymerization occurs. Drying occurs extremely quickly if the painted surface is radiated with the aim of an elp,!tron beam. Painting is suitably performed by allowing the extended object to pass through a closed tank containing the desired paint mixture. The exterd'ed object is moved along above the surface of the mixture. Above the surface of the mixture the tank is subjected to a vacuum so that paint from the liquid surface surrounds the portion of the extended object located in the tank. The painted portion then passes two polymerization units, one of which polymerizes the painted surface from below and the polymerizes the painted surface from above. The two units are displaced in relation to each other so that electronic radiation is performed first from below and then, after a short delay, from above.

WO 93/07968 PCr/SE92/00620 The use of a paint mixture consisting solely oi binder, monomer and possibly colour pigment solvent-free), avoids the drawbacks ansing out ol the use of solvent.

The painted surfaces can pass another drying means where they are dried with the aid of ultraviolet light.

The ready-painted objects may be packed, for instance, in bundles, parcels or the like.

Blanks having rectangular cross section are used for the extended objects, the cross section being sufficiently large to encompass at least two extended objects arranged side by side. Such a blank is machined so that a number of adjacent extended objects are obtained, the objects being held together in pairs by means of a blank remnant.

The use of blanks as described above offers the advantage that several extended objects can be fed along beside each other. Instead of only one extended object, a plurality of extended objects located beside each other is obtained, thus increasing the production rate as compared with single objects by the number of blanks lying parallel.

Said blank remnants are removed immediately prior to painting.

A blank for machining several extended objects is obtained from a stack of similar blanks where the blanks in the stack are arranged one after the other.

A stack of blanks is obtained by sawing one stack at a time from a stack of slabs.

The ,iabs may be produced from optional material such as wood, fiberboard, plastic or metal.

2 0 Equipment for treating the surface of the extended objects may be arranged along the production line to roughen the surfaces, thereby improving the durability of the finished paintwork.

A painting station for priming may also be arranged in the production line, in this case at a point after a number of extended objects disposed side by side have been obtained. The priming station may function similarly to the painting station described above, i.e. the WO 93/07968 PCT/SE92/00620 objects are painted on all sides. Here, too. the paint may comprise the same type ot mixture as used for painting. However, normaily it is suTficient for the extended objects to be painted from above and subsequently dned by means of ultraviolet radiation.

The installation described above greatly increases the manufacturing capacity as compared with known methods, thanks both to the use of a quick-drying paint and to several objects being moved along in parallel.

-Addi-tia al 'features, charcteri stic o the present in. entintvaled-ihe-appended---- One embodiment of the present will be described by way of example with reference to the accompanying drawing showing a block diagram of the various treating stages.

According to the c wing a number of slabs stacked one on top of the other, and possibly having an area in i~Lcess of 1 are supplied to the unit 1. From this stack of slabs one stack of blanks a a time is sawn off, with rectangular cross section, each blank in the stack being in the naiure of a plank. One stack of blanks at a time is supplied to a separating unit 2 where the individual blanks in the stack are arranged one after the other.

The blanks are then supplied from said unit 2 to a working-up unit 3 where each blank is machined mechanically by milling, for instance, so that a number of parallel extended objects are obtained, two adjacent objects being joined together by means of blank remnants. The blank with more than two extended objects is supplied to a unit 4 where each blank is roughened, by sand-papering for instance, to prepare it for a first coat of paint. After treatment in the unit 4 the blank is supplied to a painting station 6 where it is painted from above by spray painting, for instance, and where it is subsequently subjected to drying by means of ultraviolet light in a unit 7. A suitable paint for priming consists of binder, monomer and possibly colour pigment and photo-initiator.

The primed blank is supplied to a unit 8 for roughening, suitably with sand-paper. After treatment in the unit 8 the blank is ready for more paint. It is therefore conveyed from unit 8 to a unit 9 where all extended objects are separated from each other by means of milling, for instance. From unit 9 the separated extended objects are supplied to a painting unit 10. The objects entering the painting unit 10 are guided in such a manner that portions located in the painting unit 10 are freely suspended allowing them to be WO 93/07968 PCr/SE92/00620 painted on all sides. The painting unit 10 suitably comprses a closed contaner, its lower part contaning a mixture of binder, monomer and oossibly colour pigment. The portions of the extended objects located insides the closed tank are located above the surface of the paint mixture. The c!osed container is under vacuum so that paint is drawn up from the surface towards the portions of the objects located therein. The extended objects, painted on all sides and still freely suspended, are conveyed to a drying unit 11. The drying unit 11 has two electron accelerators, one operating from above and the other from below.

Painting with electron accelerators is described in detail in a publication from Polymer- Physik GmbH, entitled "Hintergrund und Neueste Anwendungen von Elektronenbestrahlungsanlagen f'ir umweltfreundlich Beschichtungs- und Laminier-Technologien".

Since painted portions of the extended objects in the drying unit 11 should be dried so that the front parts can come into contact with a support surface without the paint being damaged, drying is initiated from below and then continued after a short delay from above. Since the paint used consists of binder, monomer and possibly colour pigment, the electron beams will polymerize the coated paint, resulting in instantaneous drying, The painted and dried extended objects are supplied from unit 11 to a second drying unit 12 where they are dried only from above with the aid of UV light. From unit 12 the painted and dried extended objects are passed to a packing unit 13.

The priming unit 6 may be of the same type as the painting unit The extended object blanks are fed continuously along the entire production line.

It should be evident that painting under vacuum may be replaced with spray-painting.

Claims

1. An arrangement for painting all sides of an extended object such as rod, strip or the like, said object consisting of optional rigid material such as wood, woL1-pump board or the like, and moving continuously in longitudinal direction, including a closed container, its lower part containing a mixture of binder, monomer and pigment, a passage arrangement for the extended object allowing it to pass through the container above the surface of the mixture, a painting arrangement such as vacuum arrangement so that the extended object within the container becomes coated with a layer of the mixture, guide means such that the coated object is guided in such a way that it remains freely suspended until a drying unit has dried the object from below and it can come into contact with a support surface, and a second drying unit drying the object from above.

2. An arrangement as claimed in claim 1, wherein the two drying units include apparatuses that produce a preferably deflectable electron beam or curtain which polymerizes the monomer in the coating layer.

3. An arrangement as claimed in claim 1 or claim 2, wherein a packing station is arranged after the drying units to pack the extended units into bundles, for instance.

4. An arrangement as claimed in claim 1 including a unit for ultraviolet radiation of the object after it has passed the two drying units.

An arrangement as claimed in claim 1 including an additional painting station for providing a first coat of paint on the extended object prior to its passage through the closed container, said painting station preferably coating the object on all sides, the layer of paint being obtained in the same manner as Ssaid layer in the closed container or on all sides with the exception of the 6 contact surface.

6. An arrangement as claimed in claim 5, including a second UV radiation unit disposed after said additional painting station.

7. An arrangement as claimed in claim 5, wherein a working-up machine is disposed before the additional painting station, said machine receiving the blank for the extended object and supplying the prepared object to the painting station.

8. An arrangement as claimed in claim 7, wherein the blank is of such a width that at least two extended objects are encompassed within its cross section. •o o

9. An arrangement as claimed in claim 8 wherein at least two extended objects located side by side are obtained from the working-up machine, each object being joined to adjacent objects by an easily removed blank remnant.

An arrangement as claimed in claim 7, wherein the working-up machine is supplied with one blank at a time from a separating machine, the latter machine taking blanks from a stack and arranging them in a row.

11. An arrangement as claimed in claim 10m wherein a stock saw is arranged prior to the separating machine to saw off said stacks from a stack of slabs.

12. An arrangement as claimed in any one of the preceding claims, wherein one or more grinding stations are arranged along the path of movement of the object.

13. An arrangement as claimed in claim 9, wherein a machine is arranged to remove said blank remnants, said machines being preferably located before said closed container. DATED this 12th day of April, 1995. ANDERS LINDBLAD WATERMARK PATENT TRADEMARK ATTORNEYS 290 BURWOOD ROAD, THE GLASSHOUSE HAWTHORN VICTORIA 3122 i AUSTRALIA .i *o *o*