Abstract:
A coating device including a supply roller, a coating applicator, a driving roller and a takeup roller all cantilever mounted on a surface of a vertical panel inside a casing. A continuous base member to be coated on one side if sprially guided by guide rolls from the supply roller past the coating applicator, past the driving roller and onto the takeup roller. The base member is contacted by the rollers on the side opposite the coating.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a coating device for coating a paint on a sheet-like member and more particularly a coating device especially adapted for conducting coating tests in order to select kinds of sheet-like base members and coating liquid and the thickness of a coated layer which are best suitable for the production of articles such as magnetic tapes, thermal printer ribbons and the like consisting of a sheet-like continuous plastic-, paper- and cloth-base member coated with a coating liquid. 
     BACKGROUND OF THE INVENTION 
     With the coating device for coating a coating liquid on one surface of a continuous base member of the type described above, the coating operation is carried out in an open space so that dust particles contained in the air are mixed with a coating liquid, thus degrading the quality of finished products. In order to overcome such problem as described above, the coating operation may be carried out in an enclosed space, but there arises the problem that the coating operation is adversely affected. 
     Meanwhile, in the case of the conventional coating tests, a conventional coating device adapted for practical production is used and a coating liquid is coated on a continuous base member by manually shifting the coating device or the continuous base member. Thus when the conventional coating device is used in the coating tests, each test takes a long period of time and consequently test efficiency is low. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, a first object of the present invention is to provide a coating device which can accomplish the coating operation efficiently in an enclosed space. 
     A second object of the present invention is to provide a coating device which can accomplish various coating tests efficiently. 
     A third object of the present invention is to provide coating means best adapted for use with the coating device of the type described above. 
     In a coating device in accordance with the present invention, a supply roller upon which is mounted a roll of a continuous base member, coating means, a driving roller for driving a continuous base member, a take-up roller for rewinding a continuous base member and guide rollers for guiding a continuous base member from the supply roller to the take-up roller are all mounted like a cantilever on one surface of a single vertical panel which is surrounded with a casing. Therefore the coating operation can be carried out in an enclosed space defined by the casing and various operations for carrying out the coating operation can be accomplished on the front side of the coating device, resulting in efficient coating tests. 
     Furthermore, according to the present invention, a coating liquid supply means is mounted on a slide plate over which slides a continuous base member and a coating liquid layer having a predetermined thickness is discharged through a slit formed at the lower end of the coating liquid supply means over a continuous base member. In this manner, the coating liquid can be uniformly coated over the surface of the continuous base member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of a coating device in accordance with the present invention; 
     FIG. 2 is a longitudinal side section view thereof; and 
     FIG. 3 is a perspective view of a coating means thereof. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring first to FIGS. 1 and 2, a coating device generally designated by the reference numeral 1 is provided with a box-shaped casing 2 and a plurality of casters 3 are securely fixed to the bottom of the casing 2 so that the casing 2 is movable. A base plate 4 is extended horizontally at the lower portion of the casing 2 and an upright panel 5 is erected on the base plate 4 intermediates the front and rear sides of the casing 2. The upper end of the upright panel 5 is positioned in the vicinity of the top of the casing 2 and is supported by a ceiling plate 6 which in turn is attached to the casing 2 and is extended in the horizontal direction. The width of the upright panel 5 is substantially equal to that of the casing 2 and a door 7 is attached to the front opening of the casing 2 forwardly of the upright panel 5 so as to open the casing 2 to the exterior or to close the casing 2 from the exterior. 
     A supply roller 8 is supported like a cantilever substantially at the center of the upright panel 5 and a roll of a continuous base member 9 is rotatably mounted on the supply roller 8. A coating stand 10 is supported by the upright panel 5 immediately above the supply roller 8 and is extended forwardly. A coating means 11 to be described in detail hereinafter is mounted on the coating stand 10. An orientation device 12 is supported by the upright panel 5 and extended forwardly from the left side of the coating stand 10 (See FIG. 1). When a magnetic coating liquid is coated on a continuous base member 13 unrolled from the continuous base member roll 9, by a coating means 11, the orientation device 12 serves to improve the orientation of magnetic finely divided particles contained in the coating medium. 
     A driving roller 14 is supported like a cantilever by the upright panel 5 at a position below the horizontal center line thereof and is drivingly connected to a rotating shaft 17 of a motor 16 securely mounted on a motor stand 15 which in turn is securely mounted on the base plate 4 behind the upright panel 5. Therefore when the motor 16 is energized, the driving roller 14 is rotated. A pulley 18 to be described in detail hereinafter is mounted on the rotating shaft 17 of the motor 16. An arm 19 is pivoted with a pin 20 to the upright panel 5 in the vicinity of the driving roller 14 and carries a driven roller 21 which is in contact with the driving roller 14. The driven roller 21 is normally pressed against the driving roller 14 under the force of a bias spring (not shown). A take-up roller 22 for rewinding the coated continuous base member 13 is supported like a cantilever by the upright panel 5 on the right side of the driving roller 14 and is driven by a motor 23 as in the case of the driving roller 14. 
     A plurality of guide rollers 24A, 24B and so on are supported like a cantilever by the front surface of the upright panel 5 so as to define the passage of the continuous base member 13 which is unrolled from the continuous base member roll 9, passes through the coating means 11, the orientation device 12 and the driving roller 14 and then is wound by the take-up roller 22. These guide rollers 24A and 24B are so arranged that the continuous base member 13 unrolled from the continuous base member roll 9 is transported around the roll 9 twice along a spiral passage in the counterclockwise direction before it reaches the driving roller 14. The guide rollers 24A are driven positively while the guide rollers 24B are driven when they are made into sliding contact with the continuous base member 13. A suitable number of positive guide rollers 24A are interposed between the passive guide rollers 24B so that even when the distance between the continuous base member roll 9 and the driving roller 14 which unrolls the continuous base member 13 is relatively long, the elongation of the continuous base member 13 can be prevented. More particularly, the positive guide roller 24A most closer to the driving roller 14 carries a pulley 25 behind the upright panel 5 and an endless belt (not shown) is wrapped around the groove 26 of the pulley 25 and the groove 27 of the pulley 18 carried by the rotating shaft 17 of the motor 16 so that the rotation of the motor 16 is transmitted to the positive guide roller 24A. Endless belts (not shown) are wrapped around the grooves 28 and 29 of the positive guide pulley 25 of the positive guide roller 24A and the pulleys carried by the other positive guide rollers 24A so that the latter are positively driven. A plurality of positive and passive guide rollers 24A and 24B are used so that they are made of a aluminum and consequently the coating device 1 is light in weight. The surfaces of the guide rollers 24A and 24B are subjected to the surface treatment so as to form an alumilite layer or are plated with hard chrominum. 
     Referring next to FIG. 3, the coating means 11 has a base frame 30 mounted on the coating stand 10 and a pair of guide walls 31 are extended upwardly from the lengthwise side walls of the base frame 30 and are spaced apart from each other by a suitable distance in the widthwise direction of the continuous base member 13. A sliding plate 33 having a polished upper surface 34 such as a mirror surface of a sheet of glass is disposed on the upper surface 32 of the base frame 30 between the guide walls 31 and a coating liquid supply means 35 for supplying coating liquid to the sliding plate 33 is mounted on the upper surface 34 of the sliding plate 33. The coating liquid supply means 35 is of a rectangular cross section and has a vertical through hole 36 to define a pool of coating liquid 36 and the lengthwise ends of the coating liquid supply means 35 abut the guide walls 31, respectively. The lower side of the rear wall 37 of the coating liquid supply means 35 which is on the downstream side of the continuous base member 13 transported through the coating means 11, is formed with a slit 38 substantially over the whole length of the hole 36 in the coating medium supply means 35 and the slit 38 and the upper surface 34 of the sliding plate 33 are spaced apart from each other by a predetermined distance. A coating liquid fed into the coating liquid supply means 35 issues through the slit 38. 
     The upper side of each of the guide walls 31 is formed with a pair of arcuate recesses 39 which are spaced apart from each other by a predetermined distance in the direction in which the continuous base member 13 is transported and a pair of arcuate recesses 39 formed at the upper side of one guide wall 31 are in opposed relationship with a pair of arcuate recesses 39 formed at the upper side of the other guide wall 31. A pair of cylindrical stoppers 40 are extended between the guide walls 31 and fitted into the arcuate recesses 39 of the guide walls 31. The distance between the stoppers 40 is substantially equal to the length of the coating liquid supply means 35 in the direction in which the continuous base member 13 is transported so that the coating liquid supply means 35 is sandwiched between the stoppers 40 and is prevented from being displaced in the direction in which the continuous base member 13 is transported. 
     Referring back to FIGS. 1 and 2, operation panels 41 are attached to the upper front portion of the casing 2 and a drawer 42 for receiving tools and the like therein is provided at the lower portion of the casing 2. 
     Next the mode of operation of the coating device with the above-described construction will be described. First, the door 7 of the casing 2 is opened so that the continuous base member roll 9 is mounted on the supply roller 8 and an operator manually unwinds the continuous base member 13 from the roll 9, wraps it around the guide rollers 24A and 24B, passes it through the coating means 11, the orientation device 12 and the driving roller 14 and winds the leading edge of the continuous base member 13 around the take-up roller 22. Prior to the above-described threading operation, the coating liquid supply means 35 of the coating means 11 is removed and the continuous base member 13 is caused to slide over the upper surface 34 of the sliding plate 33. Thereafter, the coating liquid supply means 35 is mounted on the continuous base member 13 on the slide plate 33 and after a predetermined quantity of a coating liquid is fed into the coating liquid supply means 35, the door 7 is closed. Next the motors 16 and 23 are energized so that the driving roller 14 is rotated and consequently the continuous base member 13 clamped between the driving roller 14 and the driven roller 21 is pulled, whereby it is gradually unrolled from the roll 9. When the continuous base member 13 passes over the slide plate 33 of the coating means 11, the coating liquid issues through the slit 38 of the coating liquid supply means 35 over the continuous base member 13 without entraining dust particles in the coated layer. The continuous base member 13 which passed through the coating means 11 is guided by the guide roller 24B so as to enter the orientation device 12. When the magnetic coating liquid is used in the coating means 11, the orientation device 12 improves the orientation of finely divided magnetic particles contained in the coated layer. Thereafter, the continuous base member 13 is guided by the guide rollers 24A and 24B in such a way that the coated layer on the continuous base member 13 is not made in contact with the guide rollers 24A and 24B and is transported around the roll 9 about one and a half turns so that the coated liquid is dried. When the coated continuous base member 13 reaches the driving roller 14, the coated layer on the continuous base member 13 is made into contact with the driving roller 14 for the first time since it has left the coating means 11, but while the continuous base member 13 is transported a long distance between the coating means 11 and the driving roller 14, the coating liquid applied to the continuous base member 13 is already sufficiently dried. Therefore, the degradation of the quality of the coated layer on the continuous base member 13 due to the contact thereof with the driving roller 14 can be avoided. Even though the continuous base member 13 is transported a long distance from the coating means 11 to the driving roller 14, it is positively transported by the positive guide rollers 24A which are rotated by the motor 16 so that there is no possibility that the continuous base member 13 is elongated. The continuous base member 13 which has passed past the driving roller 14 and the driven roller 13 is rewound by the take-up roller 22 which is driven by the motor 23. 
     When the coating device 1 is used in coating tests, the thickness of the coated layer on the continuous base member 13 can be varied in a simple manner by replacing the coating liquid supply means 35 with another coating liquid supply means having a slit 38 of a different width. In the case of coating tests, it is preferable that the rollers 8, 14, 24A and 24B are small in size. When the coating device 1 is used in a cold northern district, it is preferable to provide as an option a heater for heating the interior of the casing 2, thereby accelerating the drying of the coated layer.