A METHOD AND A DEVICE DESIGNED FOR APPLYING COATINGS

Abstract: A method and a device designed to apply coatings, heat being used to weld or melt material layers which overlap each other. According to the invention infrared lamps (23) are used as the heat source and at least two blowers (11, 16) are used to meet the large cooling requirements and are disposed in the ends (4 and 5 respectively) of a longitudinal house (2) (one blower in each end) and designed to feed along the upper side of a reflector body (20) cooling air streams towards the central area of the device, an intense cooling of said central area being done, particularly around a recess (8) between the two house ends, in which also a manipulation handle (6) having a circuit-breaker (7) is disposed. The air is forcedly guided in order to pass the base plate (35) of the reflector body (20), mainly in its central area, and to flow from there in mutually opposite directions between the base plate and a reflector sheet as well as subsequently to flow along the front side of the device and back to the central area between the lamps and the protective glass (25), which shields the lamps forwards or downwards, and around its longitudinal edges and inwards towards the longitudinal central area of the protective glass and outwards towards the environment.

Description: A METHOD AND A DEVICE DESIGNED FOR APPLYING COATINGS The present invention relates to a method of applying coa¬ tings as well as a device designed to carry out this method. The invention particularly relates to an application of as¬ phalt-containing roof covering materials. It is already known how to heat an asphalt-containing ma¬ terial by means of an open flame and/or hot air, tempera¬ tures of from 500°C to 800°C being used. Materials in the roof construction can easily be ignited in this way and a widespread fire result, particularly when there are gaps and openings to hidden spaces in the roof construction. The number of fires have so far been so numerous, that the in¬ surance companies in many instances have refused to app¬ rove of such coating operations within the scope of the insurance protection. ϋS-A-4 869 044 relates to an application of roof coatings. The known method described in this patent uses a gas as the heat source. In this case the flames are not freely exposed against a roof but contained in a wagon having a plurality of ovens. The wagon also applies the roof paper on the roof. The object of the present invention is to eliminate these problems and provide a method as well as a device for app¬ lying coatings, which quickly and securely can be applied close to constructions and spaces, in which fires so far often have started. Another object of the invention is to obtain conditions conducive to a more controllable appli¬ cation, i.e. to limit the application as to time as well as to space to the intended areas in order to make it pos¬ sible also for a layman to easily and simply apply coa¬ tings in an acceptable way. An additional object is to re- duce environmental inconveniences, since, particularly when laymen are applying coatings, a strong smoke forma¬ tion may ensue, which is unhealthy to the operator andpos¬ sibly other persons close by. These objects are achieved according to the present in¬ vention by a method and a device respectively of the type described in the introductory portion of this specifica¬ tion, characterized by what is set forth in the characte¬ rizing clause of claim 1 and the first device claim respec¬ tively. It is important to consider the very essential air distri¬ bution according to the invention. The essential and cri¬ tical features are not a cooling in general but a cooling which has very special effects. According to the invention it is essential that two blowers are used, which have a combination effect, which is an ergonomic ideal solution and also provides a so far not known cooling and ventila¬ tion, comprising air streams which are directed against each other and alternately away from each other. Thus, the blowers continuously suck rising hot air away from the user. The air sucked in in this way then intensely cools the up¬ per portion of the device in general and particularly its handle. Thus, the handle and portions of the device adja¬ cent the handle are cooled all the time, to a considerable extent thanks to large openings disposed below the handle and centrally in the device and designed to let the main part of the cooling air pass. The cooling air then flows mainly centrally into the space between the reflector sheets and the base plate of the reflector body, an in¬ tense heating being done and the heated air streams mo¬ ving away from each other towards the short sides of the device, where a reversing takes place to direct the streams towards each other again within an area between the IR lamps and the protective glass, in which area the air streams obtain a maximum temperature and simultaneously are directed against each other, then around the protec¬ tive glass and then towards each other again, but now in a transverse or crossway direction, after which the streams are allowed to leave the device and its adjacent environ¬ ment, the latter of which is of great importance, since the heating/welding of the roof material takes place there. Even if the primary task of the air streams is to cool the upper and outer parts of the device, particularly the area around the handle, a secondary task is here not only to re¬ move but also to absorb heat, which later on during the flow will be a main task, since the air exposed against the roof coating not unnecessarily would cool the heated roof coating but instead contribute to keep the same in liquid or semi-liquid condition. The last-mentioned task is ac¬ complished to a high degree through the present invention. Thanks to its characterizing features an outer hot air curtain below and around the device is formed, which pre¬ serves the heat generation in this area. No direct cooling air will flow between the device and the coating areawhich at the moment is heated, and solely excess air is allowed to leave said area. Additional characterizing features and advantages of the present invention are set forth in the following descrip¬ tion, reference being made to the accompanying drawings, which show a preferred, not limiting embodiment, which is partly schematicly drawn. In the drawings: Fig. 1 is a detailed perspective view of a device designed to apply coatings according to the present invention; Fig. 2 is an end view from the right side in Fig. 1; Fig. 3 is a sectional view along line III-III in Fig. 2; and Fig. 4 is a sectional view along line IV-IV in Fig. 3. The device shown in the drawing is generally designated 1 and comprises a casing 2 made ofmetal and/or a plastic ma¬ terial. The casing preferably comprises two mainly mirror- symmetrical longitudinal halves, in which the mutually abut¬ ting edges may have an engagement function known per se. Said halves and/or other parts are assembled by transverse bolts 3. With a transverse .symmetrical plane the device is also roughly mirror-symmetrical. As is shown, the device, of which the height can be approximately twice as large as the width and the length 2 - 3 times the height, compri¬ ses two house ends 4 and 5, which can have the same size or almost, in case it is desirable to give the device mi¬ nimal dimensions or a minimal weight. The house ends en¬ case a handle 6, which bridges them and is provided with a press button 7 to a main circuit-breaker. A recess 8 in the casing is formed, which extends roughly parallel to the handle below the handle. This recess is open in its transverse direction, and consequently the handle can be grasped easily and quickly. The handle can be designed as a part homogenously integral with the casing, e.g. in the form of two congruent halves, if the casing consists of two parts. In one of the house ends, e.g. the front one 4, a blower 11 is mounted below a slanting upper wall 9 having abuilt- in semi-enclosure and/or a filter 10. The blower suitably is obliquely mounted with its outlet side directed towards the center of the device as regards its length. A transfor¬ mer 13 with a rectifier, designed to transform e.g. 220 V alternating current to a 14.3 V direct current is mounted between blower 11 and the adjacent recess wall 12. Blower 11 can be designed for 12 V, a rotational speed increase being attained in order to obtain an increased pressure and the rotation speed depending on the voltage. In the other house end, e.g. the rear one 5, a blower 16 is also mounted below a slanting upper wall 14 having a built- in semi-enclosure and/or a filter 15, in the same way as on the above-mentioned side. Also, a conduit entry 17 is moun¬ ted in said upper wall close to recess 8, and below the con¬ duit entry a contactor breaker 19 is mounted close towall 18 of the recess. In the drawings no electrical wires are shown and no details as regards the above-mentioned elec¬ trical components, because the wiring is self-evident and said components are known and available on the market. A reflector body 20 having upwardly projecting mounting lugs 21 is fastened on bolts 3. Lamp holders 22 for infra-red lamps 23 are mounted on the ends of body 20 and extend along the bottom side of the body, below reflector sheets 24 but above protective glasses 25, which downwardly shield the re¬ flector body and are inserted in glass holders 26,27. One or several protective glasses contact from below the inner or upper glass holder 26, whereas lower glass holder 27 is defined at each end or narrow side of the device and con¬ tacts the bottom side of the protective glass with a leg 28. Simultaneously the last-mentioned glass holder forms feet, which place the protective glass as well as the IR lamps and consequently the heat generation at a distance from a support or a surface to be heated. The long sides of the device are limited downwards bymeans of air guide plates 29, which with an upper leg 30 abut and are fastened to the long sides of the reflector body, whereas an intermediate portion 31 extends obliquely out¬ wards and downwards in order to enclose air passages 32 with the long sides of the protective glass. Terminal end legs 33 are at a level below the protective glass and pre¬ ferably somewhat above the level of the bottom side of the legs, bent towards each other in a horizontal direction. In this way the ventilation air is guided from the area outside the long sides of the protective glass to the area below the protective glass, the protective glass beingcooled and a -the same time kept clean, at least partially, from splash and other impurities, when asphalt-containing mate¬ rials are heated. The air is then allowed to escape below end legs 33. The reflector body is provided in a known way with longi¬ tudinal cooling ribs 34, which extend downwards from abase plate 35, in which transverse or vertical through holes 36 are arranged, which according to a preferred embodiment are smaller adjacent the ends of the body and larger in the central part of the body. These holes can e.g. bemore round and compact at the ends of the body and slot-like in the central part of the body, which is shown in Fig. 4. In this way a more intense passage of ventilation air through the central and hottest parts of the device is obtained, which air mainly is forced into the central portion of the reflector body (in relation to its length) and from the central portion outwards towards the ends of the reflector body between the base plate and the sheet in order to cool these parts and the device for the rest. In this way an in¬ tense cooling of recess 8 is obtained and to use two blow¬ ers is very important, since the two ends of the house in this way will be mainly uniformly cooled and an ergonomic- ly correct, well-balanced device is obtained. Two blowers provide of course also a more intense cooling than just- one blower. Of course, it is also feasible to use a pair of blowers in each end of the house, e.g. one blower in each end area of the longitudinal sides of the -house, in case extremely high cooling requirements would exist. Between the lower longitudinal sides of the casing or house and legs 30 there preferably is in a vertical direction as well as a horizontal direction through air gaps 37, which allow a cooling of these casing areas and the «guide plates. Such gaps can also be provided between legs 30 and the re¬ flector body. The end sides of the house can also be venti¬ lated,,which is shown in the lower part to the right in Fig. 4. Lower glass holders 27 are suitably provided with means for a quick attachment, known per se, to allow the protec¬ tive glass and/or the lamps to be easily and quickly ex¬ changed, cleansed etc. Of course, such means for a quick attachment can be used also between other parts of the de¬ vice. We have found, that such a device and such a method of app¬ lying coatings respectively are very advantageous, partic¬ ularly when the jobs to be done are located in not very accessible areas. The risk of fire is reduced or actually eliminated and the application process itself easier to control and guide in all respects, important environmental advantages also being obtained, since no longer e.g. an overheating and consequently a combustion of materials will take place as easily as before but solely a careful¬ ly guided and controllable heating. A more homogenous re¬ sult is also achieved. This invention has been made possible through some impor¬ tant insights, of which one insight is that splash against the protective glass, which takes place to some extent de¬ spite protective measures, and consequently fouling of the protective glass after some time will disappear through a continuous heat release on the upper side of the protec¬ tive glass. Amorphous white powders usually remain but simply falls from the protective glass. Another insight has been that the absorption properties as regards IR-ir- radiation of short wave length of bare wood, paper and the like are much worse than those of e.g. asphalt-containing coating materials, which quickly are heated and softened. The heat transmission is also done through irradiation, of which a portion is transmitted in the visible range. In this way parts in shadow and consequently hidden cavities are not heated. Also, the operator is able to see theparts which are illuminated/irradiated. The shown and described design of the device is very ad¬ vantageous from an ergonomic point of view. The operator can easily tip the device laterally and forwards/backwards, since it is constructed to normally automaticly take a po¬ sition of equilibrium, when the operator keeps the device in its handle. The device can also be left alone without damage to any sensitive parts or injuring any person or damaging any object through strongly heated parts. It is also advantageous, that the used ventilation air, mixed with smoke, is removed from the operator, the two long gaps between the guide plates and the protective glass as well as the twin blower arrangement garanteeing a quick and efficient removal of the used ventilation air. The invention is not limited to the mebodiments described and shown in the drawings,

Claims: CLAIMS 1. A method of applying coatings, particularly asphalt-con¬ taining roof covering materials, heat being used to weld or melt layers which overlap each other, c h a r a c t e ¬ r i z e d in that infra-red lamps (23) are used as a heat source, which are shielded from the coating by means of protective glass (25) and which are cooled by means of blower-generated cooling air streams in two mutually op¬ posite directions, initially directed away from each other on the rear sides of the lamps, with a more intense flow through a central area as well as along the sides and fi¬ nally towards each other between the lamps and the protec¬ tive glass, the latter being subjected also on the coa¬ ting -side to cooling and protective air flowing in oppo¬ site directions. 2. A device designed to carry out the method according to claim 1, comprising a heat source (25) for a welding or melting of overlapping layers of a coating material to be applied, particularly an asphalt-containing roof covering material, c h a r a c t e r i z e d in that the device comprises infra-red lamps (25) as a heat source in a lon¬ gitudinal house (2) , preferably divided into two parts and the two ends of which each contains a blower (11 and 16 respectively) and possibly additional electrical equip¬ ment and includes a central recess (8) , which is bridged by a handle (6) , preferably with a press button (7) for a main circuit-breaker, and in that the blowers are de¬ signed to feed cooling air along the upper or rear side of a reflector body (20) towards its central part, where larger through openings (36) .are provided than in the end areas of the reflector body, and in that air guide means are used to guide the cooling air on the interior side of the reflector body from the central portion towards the ends between its base plate (35) and the reflector sheet (24) and from the ends towards the central area on the front side of the lamps (23) and above the protective glass (25) and simultaneously outwards towards the sides around the protective glass, passing around them on the coating side through air streams directed towards each other and from there on to the environment. 3. A device according to claim 2, c h a r a c t e ¬ r i z e d in that it comprises a casing (2) made of metal and/or a plastic material, which casing consists of two mainly mirror-symmetrical longitudinal halves, in which the mutually abutting edges preferably have an engage¬ ment function known per se, the halves and/or otherparts being assembled by means of transverse bolts (3) . 4. A device according to claim 2 or 3, c h a r a c t e ¬ r i z e d in that if the symmetrical plane cuts the de¬ vice in a transverse direction, the device is roughlymir¬ ror-symmetrical, the device being roughly twice as high as wide and 2-3 times as long as high. 5. A device according to any of claims 2-4, c h a r a c ¬ t e r i z e d in that it comprises two house ends (4,5) , which have the same size or are slightly different andbet¬ ween which the handle (6) is included, which bridges them and is provided with a press button (7) , said recess (8) being designed in the casing and extending roughly paral¬ lel to the handle below it, which recess is open in the transverse direction so that the handle can be grasped easily and quickly, the handle being designed as a homo¬ genous part of the casing, e.g. in the form av two congru¬ ent halves, if the casing is divided into two parts. 6. A device according to any of claims 2-5, c h a r a c ¬ t e r i z e d in that in one of the house ends, e.g. front one (4) , one of the blowers (11) is disposed below a slan¬ ting upper side (9) having an integrated semi-enclosure and/or a filter (10) and suitably is obliquely disposed with its outlet side directed towards the central area of the device, as regards its length, and in that in the oth¬ er house end, e.g. the rear one (5) , the other blower (16) in a similar way is disposed below a also slanting upper side (14) having an integrated semi-enclosure and/or a fil¬ ter (15) . 7. A.device according to any of claims 2-6, c h a r a c ¬ t e r i z e d in that between one of the blowers (11) and the adjacent recess wall (12) a transformer (13) is dis¬ posed and provided with a rectifier for transforming e.g. a 220 V alternating current to a 14.3 V direct current, and in that said blowers (11,16) are designed for 12 V in order to run them up and obtain a pressure, the rotation speed being a function of the voltage, and/or in that in the upper side there is also provided, close to the re¬ cess (8) , a conduit entry (17) and below the same adjacent the wall (18) of the recess a contactor breaker (19) . 8. A device according to claim 3, c h a r a c t e ¬ r i z e d in that on said bolts (3) said reflector body (20) is fastened with upwardly projecting fastening lugs (21) and in that on the ends of said body (20) lamp hol¬ ders (22) for infra-red lamps (23) are disposed, which lamps extend along the bottom side of the body below said reflector sheets (24) but above the protective glass (25) , which downwards shields the reflector body and which is inserted in glass holders (26,27), of which glass holders there is one inner or upper one (26) , against which one or several protective glass panes abut from below, whereas a lower glass holder (27) is defined at each end or nar¬ row side of the device and abut with a leg (28) against the bottom side of the protective glass, last-mentioned glass holder also forming legs, which place the protective glass and consequently also the IR lamps and also the heat radiation at a distance from a support or surface to be treated. 9. A device according to any of claims 2-8, c h a r a c ¬ t e r i z e d in that the longitudinal sides of the de¬ vice are limited by air guide plates (29) , which with an upper leg (30) abut against and are fastened to the lon¬ gitudinal sides of the reflector body, whereas an interme¬ diate portion (31) extends obliquely outwards and downwards in order to include air passages (32) with the longitudinal sides of the protective glass, and/or in that terminal end legs (33) at a level below the protective glass andpre¬ ferably somewhat above the level of the bottom side of the legs are bent in a horizontal direction against eachoth¬ er in order to forcedly guide the ventilation air fromthe area outside the longitudinal sides of the protective glass to the area below the protective glass to cool and keep clean the latter at the same time at least to some extent from splash and other impurities, when an asphalt-contai- ι ning material is heated, and in order to subsequently blow out the air from below said end legs (33) . 10. A device according to any of claims 2-9, c h a r a c ¬ t e r i z e d in that the reflector body in a known way is provided with longitudinal cooling ribs (34) , which extend downwards from a base plate (35) , in which said transverse¬ ly or vertical through openings (36) are arranged, which openings are smaller adjacent the ends of the body and lar¬ ger in the central area of the body, e.g. rounder or more compact at the ends of the body and slot-like in the cent¬ ral area of the body, in order to in this way obtain amore intense ventilation air passage through the central and most heated parts of the device, which air mainly is for¬ cedly fed into the central part ( as to the length) of the reflector body and from there outwards towards the ends of the reflection body between the base plate and the sheet to cool these parts and the device for the rest, and also with an intense cooling of the recess (8) and/or in that between the lower longitudinal sides of the casing or the house and the legs (30) through air gaps (37) are provided in a vertical direction as well as in a horizontal direc¬ tion, which gaps allow a cooling of these casing areas and the guide plates, and/or in that such gaps are provided between the legs (30) and the reflector body, and/or in that the end sides of the house can be ventilated, and/or in that the lower glass holders (27) are provided with means for a quick attachment of a type known per se to al¬ low the protective glass and/or the lamps to be replaced, cleaned etc. in a simple and quick way.

Inventors: SUNDHAGE CLAES, SUNDHAGE, CLAES
Applicants: INFRAROEDTEKNIK AB
Application year: 1992
Main classification: F24C7
IPC codes: B29C35, B29C65, E04D15