JP5578909B2 - Exposure scanning device - Google Patents

Description

  The present invention relates to an exposure scanning apparatus, and more particularly to an exposure scanning apparatus suitable for manufacturing a printing plate such as a flexographic plate.

  Patent Documents 1 to 3 disclose a drawing apparatus that performs drawing (engraving) on a photosensitive material by mounting the photosensitive material on the drum and irradiating the photosensitive material with a laser while rotating the drum. In this drawing apparatus, air is ejected from obliquely above the laser irradiated position toward the laser irradiated position, and gas and dust generated by drawing are diffused. Then, by sucking the gas and dust diffused obliquely from below the laser irradiated position, the gas and dust are prevented from scattering and adhering into the laser irradiation exposure head and the drawing apparatus.

JP 2004-295985 A JP 2004-294740 A JP 2004-16013 A

  However, in the methods described in Patent Documents 1 to 3, since air is ejected toward the laser irradiated position, gas and ablation residue generated by drawing are diffused in various directions. Therefore, there is a problem that the gas and dust scattered in a direction other than obliquely below the laser irradiation position are not sucked and are attached to the exposure head for laser irradiation, and the image quality deteriorates.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an exposure scanning apparatus that guides gas and ablation debris generated by engraving to a suction hood to increase recovery efficiency.

In order to achieve the above object, an exposure scanning apparatus according to the present invention includes a substantially cylindrical main scanning drum having a recording medium fixed on its surface and rotatable in a predetermined direction, and being opposed to the main scanning drum. A first exposure head configured to irradiate a light beam toward the recording medium to engrave the surface of the recording medium, and to blow air into a space formed between the main scanning drum and the exposure head. A first nozzle that generates a flow of air along a tangential direction of the main scanning drum at an intersection between the optical axis of the exposure head and the main scanning drum; and the first nozzle A suction means for sucking air blown by the suction means, wherein an opening is provided on an extension of the flow of air generated by the first spray nozzle, and the exposure head comprises Light beam The first emission nozzle has a plurality of emission parts arranged in a predetermined direction, and a plurality of outlets arranged in the predetermined direction in the first blowing nozzle. And a flow of air having a substantially quadrangular pyramid shape having a width larger than the width of the plurality of emitting portions arranged in the predetermined direction is generated by blowing air from the plurality of outlets. And

According to the exposure scanning apparatus of the present invention, the recording medium is fixed on the surface, and is arranged in a substantially cylindrical main scanning drum that is rotatable in a predetermined direction, facing the main scanning drum, and directed toward the recording medium. The first spray nozzle that blows air into a space formed between the exposure head that engraves the surface of the recording medium by irradiating a light beam is a main nozzle at the intersection of the optical axis of the exposure head and the main scanning drum. An air flow is generated along the tangential direction of the scanning drum. The suction means has an opening located on an extension of the air flow, and sucks air blown by the first spray nozzle. Thereby, the gas and ablation debris generated by engraving can be guided to the opening together with the air, and the gas and ablation debris can be recovered. In addition, according to the exposure scanning apparatus of the present invention, a plurality of air outlets are arranged side by side in the same direction as the arrangement direction of the emitting portion that emits the light beam, and air is blown out from the plurality of air outlets. Thus, a substantially square frustum-shaped air flow having a width larger than the width of the plurality of emitting portions arranged side by side is generated. Thereby, the gas and ablation residue generated by engraving can be put on the air flow.

  In the exposure scanning apparatus according to the present invention, it is preferable that the first spray nozzle sprays air along a rotation direction of the main scanning drum. Thereby, the air flow which does not oppose the scattering direction of gas and ablation residue can be produced | generated.

  In the exposure scanning apparatus according to the present invention, it is preferable that the suction means is disposed so that a tip of a wall on the exposure head side of the opening is adjacent to an optical axis of the exposure head. Thereby, air is guided to a wall and the flow of air can be guided to an opening.

The exposure scanning apparatus according to the present invention includes a second spray nozzle that generates an air flow in a direction that cancels the air flow generated by the first spray nozzle, and the suction means includes the first spray nozzle. It is desirable to suck in air blown by the nozzle and the second blowing nozzle. The exposure scanning apparatus according to the present invention includes a substantially cylindrical main scanning drum having a recording medium fixed on the surface and rotatable in a predetermined direction, and disposed opposite to the main scanning drum. An exposure head for engraving the surface of the recording medium by irradiating a light beam toward the first, and a first spray nozzle for blowing air into a space formed between the main scanning drum and the exposure head, A first blowing nozzle that generates a flow of air along a tangential direction of the main scanning drum at an intersection of the optical axis of the exposure head and the main scanning drum; and air blown by the first blowing nozzle. Suction means for sucking in, the suction means having an opening disposed on the extension of the flow of air generated by the first blowing nozzle, and the flow of air generated by the first blowing nozzle Direction Of a second spray nozzle for generating an air flow, wherein the suction means may suck the blown by the first blowing nozzle and said second spray nozzle air.

  According to the exposure scanning apparatus of the present invention, the second blowing nozzle generates an air flow in a direction that cancels the air flow generated by the first blowing nozzle, and the air is sucked in. As a result, even if gas and ablation debris are entangled with the surface of the main scanning drum due to frictional drag and the like, the gas and ablation debris can be guided to the opening together with air, and the gas and ablation debris can be recovered. Therefore, scattering of gas and ablation debris into the apparatus can be prevented, and the collection efficiency of ablation debris can be increased.

  In the exposure scanning apparatus according to the present invention, it is preferable that the second spray nozzle generates an air flow having an acute angle with a tangential direction of the main scanning drum. Thereby, the gas and ablation tangled around the surface of the main scanning drum can be separated from the surface of the main scanning drum.

  In the exposure scanning apparatus according to the present invention, it is preferable that the second spray nozzle is disposed between the main scanning drum and the suction means. Thereby, it arrange | positions so that a 1st spray nozzle and a 2nd spray nozzle may oppose on both sides of a suction means. Therefore, the gas and ablation residue can be more efficiently separated from the surface of the main scanning drum.

  In the exposure scanning apparatus according to the present invention, the suction means includes a guide plate that guides an air flow, and the guide plate is configured to guide the air flow generated by the first spray nozzle. It is desirable that the opening is disposed in the vicinity of the opening so as to form a second opening through which the air flow generated by the second spray nozzle is guided.

  According to the exposure scanning apparatus of the present invention, in the vicinity of the opening, the first opening that induces the flow of air generated by the first spray nozzle and the air generated by the second spray nozzle. The guide plate is disposed so as to form a second opening through which the flow of the gas is guided. Thereby, the gas and the ablation residue contained in the air flow generated by each of the first spray nozzle and the second spray nozzle can be recovered from the first opening and the second opening.

  In the exposure scanning apparatus according to the present invention, it is preferable that the suction means is disposed so that a tip of a wall on the main scanning drum side of the opening is adjacent to the second spray nozzle. Thereby, the air blown from the second blowing nozzle is guided to the wall, and the air flow can be guided to the opening.

  The exposure scanning apparatus according to the present invention includes control means for controlling the air suction amount of the suction means to be larger than the air spray amounts of the first spray nozzle and the second spray nozzle. Is desirable. Thereby, the air containing gas and an ablation residue can be suck | inhaled reliably.

  In the exposure scanning apparatus according to the present invention, it is desirable that the suction means has a tubular member having a substantially constant cross-sectional area. Thereby, the flow velocity becomes constant, and it is possible to prevent gas and ablation residue from adhering to the inside of the pipe.

  According to the present invention, the gas generated by engraving and the ablation residue can be guided to the suction hood to increase the recovery efficiency.

1 is a configuration diagram of a plate making apparatus to which a multi-beam exposure scanning apparatus according to a first embodiment of the present invention is applied. Configuration diagram of optical fiber array unit arranged in exposure head Enlarged view of the light output part of the optical fiber array part Schematic diagram of the imaging optical system in the optical fiber array section Explanatory drawing which shows the relationship between the example of arrangement | positioning of the optical fiber in an optical fiber array part, and a scanning line Plan view showing an outline of a scanning exposure system in a plate making apparatus The side view which shows the positional relationship of the scanning exposure system in a plate-making apparatus, a spray nozzle, and a suction hood. The perspective view of the spray nozzle of 1st Embodiment It is a figure explaining the airflow produced | generated by the spray nozzle of 1st Embodiment, (a) is the perspective view which showed typically the spray nozzle and the airflow, (b) is the front which shows the dimension of an airflow. Figure Block diagram showing the configuration of the control system in the plate-making apparatus The figure which shows the modification of the spray nozzle of 1st Embodiment, and a suction hood. Illustration explaining the scattering of gas and ablation residue The side view which shows the positional relationship of the scanning exposure system in the plate-making apparatus which concerns on the 2nd Embodiment of this invention, a spray nozzle, and a suction hood. The perspective view of the suction hood of 2nd Embodiment Modified example of the suction hood of the second embodiment The side view which shows the positional relationship of the scanning exposure system in the plate-making apparatus which concerns on the 3rd Embodiment of this invention, a spray nozzle, and a suction hood. The perspective view of the suction hood of 3rd Embodiment Modified example of the suction hood of the third embodiment

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[First Embodiment]
<Configuration of exposure scanning apparatus>
FIG. 1 is a block diagram of a plate making apparatus 11A to which an exposure scanning apparatus according to an embodiment of the present invention is applied. In the illustrated plate making apparatus 11A, a sheet-like plate material (corresponding to a “recording medium”) is fixed to the outer peripheral surface of a drum 50 having a cylindrical shape, and the drum 50 is moved in the direction of arrow R (main scanning direction) in FIG. And a plurality of laser beams corresponding to the image data of the image to be engraved (recorded) on the plate material F are emitted from the exposure head 30 of the laser recording apparatus 10A toward the plate material F, and the exposure head 30 Is scanned at a predetermined pitch in the sub-scanning direction (arrow S direction in FIG. 1) perpendicular to the main scanning direction, a two-dimensional image is engraved (recorded) on the surface of the plate material F at high speed. Here, a case where a rubber plate or a resin plate for flexographic printing is engraved will be described as an example.

  A laser recording apparatus 10A used in the plate making apparatus 11A of this example includes a light source unit 20 that generates a plurality of laser beams, an exposure head 30 that irradiates the plate material F with a plurality of laser beams generated by the light source unit 20, and A spray nozzle 80 (not shown in FIG. 1) that blows air when the plate material F is irradiated with a laser beam, and a suction hood 81 (not shown in FIG. 1) that sucks air when the air is blown from the spray nozzle 80; And an exposure head moving unit 40 that moves the exposure head 30, the spray nozzle 80, and the suction hood 81 along the sub-scanning direction.

  The light source unit 20 includes a plurality of semiconductor lasers 21A and 21B (here, a total of 64), and the light from each of the semiconductor lasers 21A and 21B is individually exposed through the optical fibers 22A, 22B, 70A, and 70B. It is transmitted to 30 optical fiber array units 300.

  In this example, broad area semiconductor lasers (wavelength: 915 nm) are used as the semiconductor lasers 21A and 21B, and these semiconductor lasers 21A and 21B are arranged side by side on the light source substrates 24A and 24B.

  Each of the semiconductor lasers 21A and 21B is individually coupled to one end of the optical fibers 22A and 22B, and the other ends of the optical fibers 22A and 22B are connected to adapters of SC type optical connectors 25A and 25B, respectively.

  Adapter boards 23A and 23B that support the SC type optical connectors 25A and 25B are vertically attached to one end of the light source boards 24A and 24B. Also, LD driver boards 27A and 27B mounted with LD driver circuits (not shown in FIG. 1, reference numeral 26 in FIG. 10) for driving the semiconductor lasers 21A and 21B are attached to the other ends of the light source boards 24A and 24B. It has been. Each semiconductor laser 21A, 21B is connected to a corresponding LD driver circuit via an individual wiring member 29A, 29B, and each semiconductor laser 21A, 21B is individually driven and controlled.

  In this embodiment, a multimode optical fiber having a relatively large core diameter is applied to the optical fibers 70A and 70B in order to increase the output of the laser beam. Specifically, in this embodiment, an optical fiber having a core diameter of 105 μm is used. Further, semiconductor lasers 21A and 21B having a maximum output of about 10 W are used. Specifically, for example, a core having a core diameter of 105 μm and an output of 10 W (6398-L4) sold by JDS Uniphase can be used.

  On the other hand, the exposure head 30 includes an optical fiber array unit 300 that collectively emits laser beams emitted from the plurality of semiconductor lasers 21A and 21B. The light emitting section (not shown in FIG. 1, reference numeral 280 in FIG. 2) of the optical fiber array section 300 has 32 emitting ends of 64 optical fibers 70A and 70B guided from the semiconductor lasers 21A and 21B in two rows. The structure is arranged side by side (see FIG. 3).

  Further, in the exposure head 30, a collimator lens 32, an opening member 33, and an imaging lens 34 are arranged in order from the light emitting unit side of the optical fiber array unit 300. An imaging optical system is configured by the combination of the collimator lens 32 and the imaging lens 34. The opening member 33 is disposed so that the opening is positioned at the far field when viewed from the optical fiber array unit 300 side. As a result, an equivalent light amount limiting effect can be given to all laser beams emitted from the optical fiber array unit 300.

  The exposure head moving unit 40 is provided with a ball screw 41 and two rails 42 arranged so that the longitudinal direction is along the sub-scanning direction, and a sub-scanning motor (not shown in FIG. 1) that rotationally drives the ball screw 41. , The exposure head 30 disposed on the ball screw 41 can be moved in the sub-scanning direction while being guided by the rail 42. The drum 50 can be driven to rotate in the direction of arrow R in FIG. 1 by operating a main scanning motor (not shown in FIG. 1, reference numeral 51 in the figure), thereby performing main scanning.

  FIG. 2 is a configuration diagram of the optical fiber array unit 300, and FIG. As shown in FIG. 3, the light emitting section 280 of the optical fiber array section 300 is composed of optical fiber array units 300A and 300B combined in two upper and lower stages, and optical fibers 70A and 70B having the same core diameter of 105 μm in the upper and lower stages, respectively. Are arranged in two rows of 32 pieces each.

  The optical fiber array unit 300 has two bases (V-groove substrates) 302A and 302B. The bases 302A and 302B are formed on one side so that the same number of semiconductor lasers 21A and 21B, that is, 32 V-shaped grooves 282A and 282B are adjacent to each other at a predetermined interval. The bases 302A and 302B are arranged so that the V-shaped grooves 282A and 282B face each other.

  One optical fiber end 71A at the other end of the optical fiber 70A is fitted into each V-shaped groove 282A of the base 302A. Similarly, one optical fiber end 71B at the other end of each optical fiber 70B is fitted into each V-shaped groove 282B of the base 302B. That is, the optical fiber array unit 300 of the present embodiment is configured by arranging a plurality (32 in the present embodiment × 2 = 64 in total) of optical fiber end portions 71A and 71B in a straight line along a predetermined direction. Optical fiber end groups 301A and 301B are configured to be provided in two rows in parallel to a direction orthogonal to the predetermined direction.

  Therefore, these multiple (32 × 2) laser beams are simultaneously emitted from the light emitting portion 280 of the optical fiber array portion 300.

  FIG. 4 is a schematic diagram of an imaging system of the optical fiber array unit 300. As shown in FIG. 4, the light emitting section 280 of the optical fiber array section 300 is exposed to the exposure surface (surface) FA of the plate material F at a predetermined imaging magnification by the imaging means composed of the collimator lens 32 and the imaging lens 34. The image is formed in the vicinity of. Thereby, the intersection I between the optical axis L and the exposure surface (surface) FA is engraved (image recording). In the present embodiment, the imaging magnification is set to 1/3, so that the spot diameter of the laser beam LA emitted from the optical fiber end portions 71A and 71B having the core diameter of 105 μm is φ35 μm.

  In the exposure head 30 having such an image forming system, the distance between the upper and lower stages of the optical fiber array units 300A and 300B described in FIG. 3 (L1 in FIG. 3) and the relative position in the column direction (L2 in FIG. 3). ), The interval between adjacent fibers in the row (L3 in FIG. 3), and the inclination angle (angle θ in FIG. 5) of the arrangement direction (array direction) of the optical fiber end groups 301A and 301B when fixing the optical fiber array unit 300 Are appropriately designed, as shown in FIG. 5, optical fiber end portions 71A arranged at adjacent positions in each row of the upper array stage (optical fiber end group 301A) and lower array stage (optical fiber end group 301B), The interval P1 of the scanning line (recording line) K exposed by the laser beam emitted from 71B, the optical fiber end 71AT at the right end of the upper stage of the array, and the array It is possible to set the interval P2 of the scanning line K of the exposure at the left end of the optical fiber end portion 71BT stages respectively equal 10.58Myuemu (sub-scanning direction resolution 2400dpi equivalent). In FIG. 5, the number of optical fibers is reduced for the convenience of illustration. That is, the design of the optical fiber array unit 300 can realize a scanning line interval (P1 = P2≈10.6 μm) with a resolution of 2400 dpi in the sub-scanning direction with 64 channels.

  By using the exposure head 30 having the above-described configuration, it is possible to simultaneously scan and expose a range of 64 lines (one swath) in two rows of the optical fiber end group 301A and 301B of the optical fiber array unit 300.

  FIG. 6 is a plan view showing an outline of a scanning exposure system in the plate making apparatus 11A shown in FIG. The exposure head 30 includes a focus position changing mechanism 60 and an intermittent feed mechanism 90 in the sub-scanning direction.

  The focus position changing mechanism 60 has a motor 61 and a ball screw 62 that move the exposure head 30 back and forth with respect to the drum 50 surface. Under the control of the motor 61, the focus position can be moved about 300 μm in about 0.1 seconds. it can. The intermittent feed mechanism 90 constitutes the exposure head moving unit 40 described with reference to FIG. 1, and includes a ball screw 41 and a sub-scanning motor 43 that rotates the ball screw 41 as shown in FIG. The exposure head 30 is fixed to a stage 44 on the ball screw 41, and is controlled by the sub-scanning motor 43 to move the exposure head 30 in the direction of the axis 52 of the drum 50, that is, in the sub-scanning direction by about 1 second. (640 μm) can be intermittently fed to the adjacent swath.

  In FIG. 6, reference numerals 46 and 47 denote bearing blocks that rotatably support the ball screw 41. Reference numeral 55 denotes a chuck member that chucks the plate material F on the drum 50. The position of the chuck member 55 is a non-recording area where exposure (recording) by the exposure head 30 is not performed.

  While rotating the drum 50, the plate material F on the rotating drum 50 is irradiated with a laser beam of 64 channels from the exposure head 30, so that an exposure range 92 for 64 channels (one swath) can be formed without a gap. Exposure is performed, and engraving (image recording) of 1 swath width is performed on the surface of the plate material F. Then, when the chuck member 55 passes in front of the exposure head 30 by the rotation of the drum 50 (at the non-recording area of the plate material F), intermittent feeding is performed in the sub-scanning direction to expose the next one swath. To do. A desired image is formed on the entire surface of the plate F by repeating exposure scanning by intermittent feeding in the sub-scanning direction.

  In this example, a sheet-like plate material F (recording medium) is used, but a cylindrical recording medium (sleeve type) can also be used.

  When engraving (image recording) having a swath width on the surface of the plate material F, air is blown from the spray nozzle 80 and air is sucked from the suction hood 81. FIG. 7 is a side view showing the positional relationship among the scanning exposure system, the spray nozzle 80, and the suction hood 81 in the plate making apparatus 11A.

  The spray nozzle 80 and the suction hood 81 are disposed between the exposure head 30 and the drum 50. The spray nozzle 80 generates an air flow A <b> 1 in a space formed between the exposure head 30 and the drum 50. The spray nozzle 80 and the suction hood 81 are arranged to face each other so that air blown from the spray nozzle 80 can be sucked from the suction hood 81.

  As shown in FIG. 8, the blowing nozzles 80 are provided with the blowing ports 80a arranged in a line, and air is jetted from the respective blowing ports 80a. Thereby, as shown to Fig.9 (a), from the whole spray nozzle 80, the substantially square pyramid trapezoid airflow A1 is produced | generated. FIG. 9B is a diagram of the substantially square pyramid trapezoidal airflow A1 as viewed from the front side of the spray nozzle 80, and shows a specific example of the size of the airflow A1.

  The airflow A1 has a width of 54 mm at a position 30 mm away from the outlet 80a, a width of 100 mm at a position 150 mm away from the outlet 80a, and a width at a position 300 mm away from the outlet 80a. It becomes 160 mm. Further, the depth of the airflow A1 is adjusted so as to suppress the spread and become a flat shape. The speed of the air flow A1 is experimentally determined according to the output of the laser beam and the rotational speed of the drum 50.

  As shown in FIG. 7, the spray nozzle 80 is arranged so that the arrangement direction of the outlets 80a is substantially parallel to the axis 52 of the drum 50, that is, the arrangement direction of the outlets 80a is the arrangement direction of the optical fiber end portions 71A and 71B. It is arrange | positioned so that it may become the same. Also, the blowing nozzle 80 has an air flow in a plane M in which the blowing direction of air from the blowing port 80a is the same as the rotation direction R of the drum 50 and passes through the blowing port 80a and is orthogonal to the arrangement direction of the blowing ports 80a ( Hereinafter, AM1 (referred to as an air flow center plane) (see FIG. 9A) is disposed so as to be parallel to the tangent line of the drum 50 at the intersection I between the optical axis L and the exposure surface FA. Accordingly, a substantially downward air flow in FIG. 9 is generated at the position of the intersection I between the optical axis L and the exposure surface FA. Therefore, gas and ablation debris generated by engraving are conveyed downward, and scattering of gas and ablation debris in other directions is prevented.

  Further, the spray nozzle 80 is arranged so that the light emitting portion 280 is located at a position where the distance from the outlet 80a is approximately 51 mm so that the width of the airflow A1 is larger than the light emitting portion 280 of the optical fiber array portion 300. Established. Thereby, the gas and ablation residue generated by engraving can be put on the airflow A1. In addition, the relationship between the spray nozzle 80 and the light emission part 280 is not limited to this, It can be set as various positional relationships that the width | variety of the airflow A1 becomes larger than the light emission part 280.

  The suction hood 81 is a tubular member having a substantially rectangular cross section having a substantially rectangular opening 81a, and air is supplied from the opening 81a by a pump (not shown) connected to an opening other than the opening 81a. Inhaled (see arrow in FIG. 7). The amount of air sucked from the suction hood 81 is set to be larger than the amount of air blown from the spray nozzle 80.

  An opening 81a is provided on the extension of the airflow A1. The opening 81a is formed to be larger than the size of the airflow A1 at that position. In the present embodiment, the suction hood 81 is disposed at a position where the distance from the outlet 80a is approximately 150 mm, so that the width of the opening 81a of the suction hood 81 is 100 mm or more. Thereby, the airflow A1 including gas and ablation residue can be reliably sucked from the suction hood 81.

  The suction hood 81 is formed so that the cross-sectional area is substantially constant. Thereby, the flow velocity in the suction hood 81 can be made constant, the sucked gas and ablation residue can be prevented from adhering to the suction hood 81, and the amount of adhesion can be reduced.

<Control system configuration>
FIG. 10 is a block diagram showing the configuration of the control system of the plate making apparatus 11A. As shown in FIG. 10, the plate making apparatus 11A includes an LD driver circuit 26 that drives the semiconductor lasers 21A and 21B in accordance with the two-dimensional image data to be engraved, a main scanning motor 51 that rotates the drum 50, A main scanning motor driving circuit 101 that drives the scanning motor 51, a sub scanning motor driving circuit 102 that drives the sub scanning motor 43, and a control circuit 100 are provided. The control circuit 100 controls the LD driver circuit 26 and each motor drive circuit (101, 102).

  Image data indicating an image to be engraved (recorded) on the plate material F is supplied to the control circuit 100. The control circuit 100 controls the driving of the main scanning motor 51 and the sub-scanning motor 43 based on this image data, and individually controls the output (laser beam power control) for each of the semiconductor lasers 21A and 21B. The means for controlling the output of the laser beam is not limited to the mode of controlling the light emission amount of the semiconductor lasers 21A and 21B, but instead of this or in combination with this, an acoustic light modulator (AOM: Acoustic Optical Modulator). Light modulation means such as a unit may be used.

  Next, the exposure scanning process when manufacturing a printing plate by a multi-beam exposure system will be described. The exposure scanning process is mainly controlled by the control circuit 100. In the present embodiment, in a multi-beam exposure system that scans and exposes the same scanning line a plurality of times, the planar shape to be left on the exposure surface of the recording medium and the large frame of the inclined portion are formed by the first beam group (coarse engraving process) Then, after the temperature of the plate material F raised in the rough engraving process is lowered to a predetermined temperature, exposure scanning is performed on the same scanning line with the second beam group having energy lower than the energy irradiated from the first beam group to the recording medium. Then, a multi-exposure scanning method is employed in which the final shape (target surface shape and inclined portion) is finely engraved precisely (fine engraving process).

  When the image data is supplied to the control circuit 100, the control circuit 100 blows air from the blowing nozzle 80 to generate an air flow A1 and starts sucking air from the suction hood 81 before starting engraving. . After that, engraving is started as follows.

  While the drum 50 is rotated at a constant speed, the plate material F is exposed and scanned by the first beam group (64 channels) emitted from the exposure head 30 to engrave the first shape. The first scanning exposure step by the first beam group is a step of performing rough engraving that does not reach the shape of the surface finally left as the convex flat portion and the shape of the inclined portion. When the drum 50 rotates once, rough engraving is performed with a width of 64 channels. Thereafter, at the same sub-scanning position (without moving the exposure head 30), the second beam group of lower power (same channel as the first beam group) on the same line at the same place in the second rotation of the drum 50. Scan exposure is performed to form a final shape (second shape).

  In this way, after engraving for one swath is completed by two rotations of the drum 50, the exposure head 30 is moved in the sub-scanning direction (rightward in FIG. 1) when the chuck member 55, which is a non-recording area, crosses the front of the exposure head 30. ) Intermittently, and moved to a position for engraving the next adjacent swath. Then, exposure scanning of coarse engraving and fine engraving by the first beam group is performed at the position.

  Thereafter, the above process is repeated to expose the entire surface of the plate material F. The specific control mode of power control differs depending on the sensitivity (reactivity to light) of the plate material (flexo sensitive material) to be used. Appropriate output conditions are experimentally determined according to the type of printing plate.

  When engraving is completed, the blowing of air from the blowing nozzle 80 is stopped, and then the suction of air from the suction hood 81 is stopped.

  According to the present embodiment, the gas and ablation residue generated by engraving can be guided to the suction hood together with the air flow. Therefore, the recovery efficiency of gas and ablation residue can be increased. Thereby, scattering of gas and ablation residue into the plate making apparatus is prevented.

  In addition, in this Embodiment, although the suction hood 81 which has the substantially rectangular opening part 81a was used, the shape of the suction hood 81 is not restricted to this. For example, as shown in FIG. 11A, a wall 81b may be disposed on the exposure head 30 side of the opening 81a. The wall 81b is formed so that the highest position is located below the optical axis L. In addition, a hole 81d 'is formed at the upper end of the wall 81b so that the wall 81b does not interfere with the laser beam. Thereby, the position where the air flow A1 is guided to flow downward is close to the outlet 80a, and the suction efficiency of gas and ablation residue can be increased. In FIG. 11A, the shape of the hole 81d 'is a substantially half moon shape, but the shape is not limited to this.

  In order to further enhance this effect, as shown in FIG. 11B, in addition to the wall 81b on the exposure head 30 side of the opening 81a, a wall 81c may be provided on the side surface. Further, as shown in FIG. 11C, a wall 81b ′ and a side wall 81c ′ formed at a height that covers the spray nozzle 80 are provided, and a hole 81d through which the laser beam passes is formed in the wall 81b ′. You may make it do. Furthermore, a wall 81e may be disposed on the drum 50 side of the opening 81a. Thereby, it becomes easy to guide the airflow A1 into the suction hood.

  Further, as shown in FIG. 11D, walls 81b ″, 81c ″, 81e are provided so as to cover the outlet 80a of the spray nozzle 80, and a hole 81d through which the laser beam penetrates the wall 81b ″. The hole 81f through which the laser beam passes may be formed in 81e. In this case, since all the airflow A1 is covered with the suction hood, almost all of the gas and ablation residue can be recovered.

  The walls 81c, 81c ′, 81cc ″ are part of a substantially rectangular shape at a position offset by a predetermined distance from the circuit line r of the chuck member 55 accompanying the rotation of the drum 50 so as not to interfere with the chuck member 55. It is formed to have a shape from which is removed. The wall 81e is formed by an arcuate surface having a radius of a length obtained by adding an offset distance to the radius of the circuit line r.

  In FIGS. 11 (c) and 11 (d), a hole 81d and a hole 81f ′ through which laser light passes are formed, but these holes are round holes with a diameter of about several millimeters and are small in size. By the flow A1, air is sucked into the suction hoods 81 ′ ″ and 81 ″ ″ from the holes 81d and 81f ′ at a flow velocity higher than that of the air flow A1. Therefore, these holes do not lose the effect of having the suction hood at a height that covers the spray nozzle 80, and on the contrary, contamination of the imaging lens 34 and the like can be reduced.

  In the present embodiment, the blowing nozzle 80 is disposed so that the blowing direction of the air from the blowing port 80a is the same as the rotation direction R of the drum 50, but the blowing direction of the air from the blowing port 80a is the drum. The spray nozzle 80 may be disposed so as to be opposite to the rotation direction R of 50. However, the gas and ablation debris have a predetermined angle in the direction opposite to the sub-scanning direction S with respect to the rotation direction R of the drum 50 due to the wall formed in the plate material F by exposure as shown by an arrow X in FIG. There is a tendency to scatter in the direction it has. Therefore, it is desirable to arrange the spray nozzle 80 so that the air blowing direction from the blowing port 80a is the same direction as the rotation direction R of the drum 50 so as not to oppose the gas and ablation residue scattering direction.

[Second Embodiment]
The first embodiment of the present invention is generated by engraving by arranging the spray nozzle 80 and the suction hood 81 so as to face each other, blowing air from the spray nozzle 80 and sucking air from the suction hood 81. Although the gas and ablation debris are collected, there is a possibility that not all the gas and ablation debris are collected in the suction hood 81 due to the physical limitation that the suction hood can be disposed only outside the circuit line r of the chuck member 55.

  In particular, depending on the rotational speed of the drum 50, gas and ablation residue are entangled with the surface of the drum 50 (plate material F) as the drum 50 rotates due to frictional drag from the drum 50 (plate material F). It may flow like In such a case, the recovery efficiency further decreases.

  In the second embodiment of the present invention, gas and ablation residue entangled on the surface of the drum 50 (plate material F) are conveyed to the suction hood by airflow. Hereinafter, the plate making apparatus 11B according to the second embodiment will be described. In addition, about the part same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The plate making apparatus 11B fixes a sheet-like plate material (corresponding to “recording medium”) to the outer peripheral surface of a drum 50 having a cylindrical shape, rotates the drum 50 in an arrow R direction (main scanning direction), and A plurality of laser beams corresponding to image data of an image to be engraved (recorded) are emitted from the exposure head 30 of the laser recording apparatus 10B toward the material F, and the exposure head 30 is orthogonal to the main scanning direction. The two-dimensional image is engraved (recorded) on the surface of the plate material F at a high speed by scanning at a predetermined pitch in the sub-scanning direction (arrow S direction).

  A laser recording apparatus 10B used in the plate making apparatus 11B includes a light source unit 20 that generates a plurality of laser beams, an exposure head 30 that irradiates the plate material F with a plurality of laser beams generated by the light source unit 20, and a laser beam. Blowing nozzles 80 and 82 that blow air when irradiating the printing plate F, a suction hood 83 that sucks air when blowing air from the blowing nozzle 80, and the exposure head 30, the blowing nozzles 80 and 82, and the suction hood 83 are arranged in the sub-scanning direction. And an exposure head moving unit 40 that is moved along the direction.

  FIG. 13 is a side view showing the positional relationship among the scanning exposure system, the spray nozzles 80 and 82, and the suction hood 83 in the plate making apparatus 11B.

  The spray nozzle 80 and the suction hood 83 are disposed between the exposure head 30 and the drum 50. The spray nozzle 80 and the suction hood 83 are arranged to face each other so that air blown from the spray nozzle 80 can be sucked from the suction hood 81.

  The spray nozzle 82 is disposed between the drum 50 and the suction hood 83. As with the spray nozzle 80, the spray nozzles 82 are arranged in a row, and air is ejected from each of the spray nozzles, thereby generating a substantially square frustum-shaped air flow A2. The width of the airflow A2 is equal to or less than the width of the airflow A1, and the amount of the airflow A2 is controlled to be smaller than the amount of the airflow A1. In the present embodiment, the ratio of the amount of airflow A1 to the amount of airflow A2 is set to be about 5 to 1, but the specific control mode varies depending on the rotational speed of the drum 50. Appropriate conditions are determined experimentally.

  As shown in FIG. 13, the blowing nozzle 82 has an air blowing direction from the blowing port opposite to the rotation direction R of the drum 50, and includes an air flow center plane AM 2, an air flow center plane AM 2, and a plate material F. The angle θ formed by the tangent at the intersection is arranged to be an acute angle. Thereby, the gas and ablation residue entangled on the surface of the drum 50 (plate material F) can be peeled off from the surface of the drum 50 (plate material F).

  The spray nozzle 80 and the spray nozzle 82 are disposed so as to face each other with the suction means interposed therebetween. Therefore, gas and ablation residue can be peeled from the drum 50 (plate material F) at a position farther from the spray nozzle 80. Therefore, gas and ablation residue can be efficiently peeled off.

  As shown in FIG. 14, the suction hood 83 has the tip of the wall 83 a on the exposure head 30 side adjacent to the optical axis, and the tip of the wall 83 b on the drum 50 side and the tips of the walls 83 c on both sides are the circulation lines of the chuck member 55. It is a tubular member formed substantially along r, and is formed so that its width is equal to or greater than the width of the airflow A1.

  The walls 83a, 83b, 83c form a substantially rectangular opening. A guide plate 83d for guiding the air flow is disposed in the opening. The guide plate 83 d is formed with a width substantially the same as the width of the suction hood 83 and is integrally formed on the walls on both sides of the suction hood 83. As shown in FIG. 13, the guide plate 83d forms a first opening 83A through which the airflow A1 is guided and a second opening 83B through which the airflow A2 is guided (see FIG. 13). ).

  The guide plate 83d is in contact with the circuit line r of the chuck member 55 as the drum 50 rotates, and the area d1 of the first opening 83A and the area d2 of the second opening 83B are in the vicinity of the other end of the suction hood 83. It is disposed at a position substantially the same as the area d3. Thereby, the flow velocity of the air in the suction hood 83 becomes constant, it is possible to prevent the ablation residue from adhering in the suction hood 83, and to reduce the amount of adhesion.

  A pump (not shown) is connected to the other end of the suction hood 83, and air is sucked from the first opening 83A and the second opening 83B (see arrow (4) in FIG. 13). The amount of air sucked in the first opening 83A and the second opening 83B is set to be larger than the total amount of air blown from the blowing nozzles 80 and 82.

  Most of the airflow A1 including gas and ablation debris is sucked from the first opening 83A (see arrow (1) in FIG. 13). However, the physical restriction of the guide plate 83d (the guide plate 83d is outside the circuit line r of the chuck member 55) and the air flow including gas and ablation residue are entangled on the surface of the drum 50 (plate material F). Part of the airflow A1 flows downward between the guide plate 83d and the drum 50 (plate material F) (see arrow (2) in FIG. 13).

  The airflow that flows downward between the guide plate 83d and the drum 50 (plate material F) is peeled off from the drum 50 (plate material F) by the airflow A2 and wound up upward (arrow in FIG. 13). (See (3)). The air wound up by the airflow A2 is sucked from the second opening 83B. Thereby, the gas and ablation debris sent together with the air flows A <b> 1 and A <b> 2 can be reliably sucked from the suction hood 83.

  Next, the exposure scanning process when manufacturing a printing plate by a multi-beam exposure system will be described. The exposure scanning process is mainly controlled by the control circuit 100. In the present embodiment, a multiple exposure scanning method is employed in which the rough engraving process and the fine engraving process are continuously performed.

  When image data is supplied to the control circuit 100, the control circuit 100 blows air from the spray nozzles 80 and 82 to generate air flows A1 and A2 and starts air flow from the suction hood 83 before starting engraving. Start sucking. Then start engraving. Since engraving is the same as in the first embodiment, description thereof is omitted.

  When exposure of the entire surface of the plate material F is completed, the blowing of air from the blowing nozzles 80 and 82 is stopped, and then the suction of air from the suction hood 83 is stopped.

  According to the present embodiment, even if gas and ablation debris are entangled with the surface of the drum (plate material) due to frictional drag from the drum (plate material) or the like, Can be reliably sucked from the suction hood. Therefore, scattering of gas and ablation debris into the apparatus can be prevented, and the collection efficiency of ablation debris can be increased.

  In the present embodiment, the tip of the wall 83a on the exposure head 30 side is adjacent to the optical axis, and the tip of the wall 83b on the drum 50 side and the tip of the walls 83c on both sides are substantially along the circumferential line r of the chuck member 55. However, the shape of the suction hood 83 is not limited to this. For example, as shown in FIG. 15, a wall 83 a ′ and a side wall 83 c ′ (not shown in FIG. 15) formed at a height that covers the spray nozzle 80 are disposed, and the tip is a blowout port of the spray nozzle 82. The wall 83b ′ adjacent to the wall 83a ′ may be disposed so that the openings formed by the walls 83a ′, 83b ′, 83c ′ cover the entire air flows A1, A2. As a result, the airflows A1 and A2 are easily guided to the suction hood 83, and the suction efficiency of gas and ablation residue can be increased.

[Third Embodiment]
In the second embodiment of the present invention, the spray nozzle 80 and the suction hood 81 are arranged to face each other, and air is blown from the spray nozzle 80 and gas entangled on the surface of the drum 50 (plate material F), By transporting the ablation debris to the suction hood by air flow, the gas and ablation debris generated by engraving were collected. However, when the rotation speed of the drum 50 is higher than a predetermined speed, most of the gas and ablation debris are drums. Since it flows so as to be entangled with the surface of the plate 50 (plate material F), the blowing of air from the blowing nozzle 80 is not essential.

  In the third embodiment of the present invention, gas and ablation residue entangled on the surface of the drum 50 (plate material F) are conveyed to the suction hood by airflow. Hereinafter, a plate making apparatus 11C according to the third embodiment will be described. In addition, about the part same as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The plate making apparatus 11C fixes a sheet-like plate material (corresponding to “recording medium”) to the outer peripheral surface of a drum 50 having a cylindrical shape, rotates the drum 50 in an arrow R direction (main scanning direction), and A plurality of laser beams corresponding to image data of an image to be engraved (recorded) is emitted from the exposure head 30 of the laser recording apparatus 10C toward the material F, and the exposure head 30 is orthogonal to the main scanning direction. The two-dimensional image is engraved (recorded) on the surface of the plate material F at a high speed by scanning at a predetermined pitch in the sub-scanning direction (arrow S direction).

  A laser recording apparatus 10C used in the plate making apparatus 11C includes a light source unit 20 that generates a plurality of laser beams, an exposure head 30 that irradiates the plate material F with the plurality of laser beams generated by the light source unit 20, and a laser beam. The spray nozzle 84 that blows air when irradiating the plate material F, the suction hood 85 that sucks air when air is blown from the spray nozzle 84, and the exposure head 30, the spray nozzle 84, and the suction hood 85 are moved along the sub-scanning direction. And an exposure head moving unit 40 to be operated.

  FIG. 16 is a side view showing a positional relationship among the scanning exposure system, the spray nozzle 84, and the suction hood 85 in the plate making apparatus 11C.

  The spray nozzle 84 is disposed between the drum 50 and the suction hood 85. The blowing nozzles 82 are arranged in a row with the outlets, and air is ejected from each outlet, thereby generating a substantially square frustum-shaped air flow A3.

  The spray nozzle 84 generates an airflow A3 having a width wider than that of the optical fiber array unit 300. Although the wind speed of the airflow A3 varies depending on the rotational speed of the drum 50, appropriate conditions are experimentally determined.

  As shown in FIG. 16, the blowing nozzle 84 has an air blowing direction opposite to the rotation direction R of the drum 50, and the air flow center plane AM3, the air flow center plane AM3, and the plate material F. The angle formed by the tangent at the intersection is arranged to be an acute angle. Thereby, the gas and ablation residue entangled on the surface of the drum 50 (plate material F) can be peeled off from the surface of the drum 50 (plate material F) and rolled up (see arrow (2) in FIG. 15).

  As shown in FIG. 17, the suction hood 85 has the tip of the wall 85 a on the exposure head 30 side adjacent to the optical axis, and the tip of the wall 85 b on the drum 50 side and the tips of the walls 85 c on both sides are the circulation lines of the chuck member 55. It is a tubular member formed substantially along r. Thereby, the suction hood 85 is disposed so that the substantially rectangular opening 85A formed by the front ends 85a, 85b, and 85c of each wall covers the surface of the drum 50 (plate material F).

  Since the tip of the wall 85b on the drum 50 side is formed substantially along the circumferential line r of the chuck member 55, the tip of the wall 85b is the intersection I of the optical axis L and the exposure surface (surface) FA, that is, the engraving point. It is located on the drum 50 side from directly below. Therefore, even if the ablation residue falls directly below the intersection point I, the ablation residue is guided into the suction hood 85.

  The gas and ablation residue generated by engraving flow downward along the drum 50 (plate material F) as the drum 50 rotates (see arrow (1) in FIG. 13). A pump (not shown) is connected to the other end of the suction hood 85, and air is sucked from the opening 85A (see arrow (4) in FIG. 13).

  The gas and ablation residue that have flowed downward are peeled off from the surface of the drum 50 (plate material F) by the airflow A3 and wound upward (see arrow (2) in FIG. 15). The tip 85b of the wall on the drum 50 side is located on the spray nozzle 84 side from the intersection J between the airflow center plane AM3 and the plate material F. For this reason, the gas and ablation residue wound up by the airflow A3 are reliably guided into the suction hood 85.

  Further, the gas flowing downward and a part of the ablation residue peel off from the drum 50 (plate material F) (see arrow (4) in FIG. 15). However, since the region where the gas and ablation debris peel is within the space covered by the tips 85a, 85b and 85c of each wall, the peeled gas and ablation debris are also reliably guided into the suction hood 85.

  Thereby, gas and ablation residue can be reliably sucked from the suction hood 85.

  Next, the exposure scanning process when manufacturing a printing plate by a multi-beam exposure system will be described. The exposure scanning process is mainly controlled by the control circuit 100. In the present embodiment, a multiple exposure scanning method is employed in which the rough engraving process and the fine engraving process are continuously performed.

  When the image data is supplied to the control circuit 100, the control circuit 100 blows air from the blowing nozzle 84 to generate an air flow A3 and starts sucking air from the suction hood 85 before starting engraving. . Then start engraving. Since engraving is the same as in the first embodiment, description thereof is omitted.

  When exposure of the entire surface of the plate material F is completed, the blowing of air from the blowing nozzle 84 is stopped, and then the suction of air from the suction hood 85 is stopped.

  According to the present embodiment, even if gas and ablation debris are entangled with the surface of the drum (plate material) due to frictional drag from the drum (plate material) or the like, Can be reliably sucked from the suction hood. Therefore, scattering of gas and ablation debris into the apparatus can be prevented, and the collection efficiency of ablation debris can be increased.

  In the present embodiment, the tip of the wall 85a on the exposure head 30 side is adjacent to the optical axis, and the tip of the wall 85b on the drum 50 side and the tip of the walls 85c on both sides are substantially along the circumferential line r of the chuck member 55. However, the shape of the suction hood 85 is not limited to this. For example, as shown in FIG. 18, a wall 85 a ′ and a side wall 85 c ′ (not shown in FIG. 17) formed at a height that covers the spray nozzle 80 are disposed, and the tip is a blowout port of the spray nozzle 84. The wall 5b ′ adjacent to the wall 5b ′ may be disposed so that the opening 85A ′ formed by the walls 85a ′, 85b ′, and 85c ′ covers the entire air flow A3. Thereby, the suction efficiency of gas and ablation residue can be increased. Also in the case shown in FIG. 18, the suction hood 85 ′ is formed so that the tip of the wall 85 b ′ is located on the drum 50 side from the intersection I of the optical axis L and the exposure surface (surface) FA, that is, directly below the engraving point. Is done. Therefore, even if the ablation residue falls directly below the intersection I, the ablation residue is guided into the suction hood 85 '.

  In the embodiment of the present invention, the opening of the suction hood is formed in a substantially rectangular shape, but the shape of the opening is not limited to a substantially rectangular shape. Depending on the size of the light emitting section 280 of the optical fiber array section 300 and the distance between the drum 50 and the exposure head 30, it may be substantially square. Moreover, the opening part of a suction hood The opening part of a suction hood is not limited to substantially rectangular shapes, such as a substantially rectangular shape and a substantially square shape. The two opposing surfaces (the exposure head 30 side and the drum 50 side) only need to be parallel. For example, a substantially oval opening having the other two surfaces formed in an arc shape may be employed.

  In the embodiment of the present invention, the case of using the scanning exposure method by intermittent feeding in the sub-scanning direction has been described as an example. However, the plate material F is moved by moving the exposure head 30 at a constant speed in the sub-scanning direction while the drum is rotating. A spiral exposure method of scanning the surface of the substrate in a spiral shape may be employed.

  10A, 10B, 10C ... laser recording device, 11A, 11B, 11C ... plate making device, 20 ... light source unit, 21A, 21B ... semiconductor laser, 22A, 22B, 70A, 70B ... optical fiber, 30 ... exposure head, 40 ... exposure head Moving unit, 50 ... drum, 80, 82, 84 ... spray nozzle, 81, 83, 85 ... suction hood, 90 ... control circuit, 300 ... optical fiber array unit, 512 ... interlace region, 514 ... non-interlace region, A1, A2 A3: Air flow, F: Plate material, K: Scanning line, L: Optical axis

Claims (11)

A substantially cylindrical main scanning drum having a recording medium fixed to the surface and rotatable in a predetermined direction;
An exposure head that is disposed opposite the main scanning drum and engraves the surface of the recording medium by irradiating a light beam toward the recording medium;
A first spray nozzle that blows air into a space formed between the main scanning drum and the exposure head, the tangent of the main scanning drum at the intersection of the optical axis of the exposure head and the main scanning drum A first spray nozzle for generating a flow of air along the direction;
A suction means for sucking air blown by the first blowing nozzle, wherein the suction means has an opening disposed on an extension of the flow of air generated by the first blowing nozzle ;
The exposure head is an emitting unit that emits the light beam, and has a plurality of emitting units arranged in a predetermined direction,
The first spray nozzle has a plurality of outlets arranged side by side in the predetermined direction,
Exposure is characterized in that air is blown out from the plurality of outlets to generate a substantially square frustum-shaped air flow having a width larger than the width of the plurality of emitting portions arranged in the predetermined direction. Scanning device. A second spray nozzle for generating an air flow in a direction to cancel the air flow generated by the first spray nozzle;
The suction means, an exposure scanning apparatus according to claim 1, characterized in that sucking air blown by the first blowing nozzle and said second spray nozzle. A substantially cylindrical main scanning drum having a recording medium fixed to the surface and rotatable in a predetermined direction;
An exposure head that is disposed opposite the main scanning drum and engraves the surface of the recording medium by irradiating a light beam toward the recording medium;
A first spray nozzle that blows air into a space formed between the main scanning drum and the exposure head, the tangent of the main scanning drum at the intersection of the optical axis of the exposure head and the main scanning drum A first spray nozzle for generating a flow of air along the direction;
Suction means for sucking air blown by the first blowing nozzle, wherein the suction means has an opening disposed on an extension of the flow of air generated by the first blowing nozzle;
A second spray nozzle that generates a flow of air in a direction that cancels the flow of air generated by the first spray nozzle;
The exposure scanning apparatus , wherein the suction unit sucks air blown by the first spray nozzle and the second spray nozzle . The second spray nozzle, the exposure scanning apparatus according to claim 2 or 3 the angle between the tangential direction of the main scanning drum and generates a flow of air which is an acute angle. The second spray nozzle, the exposure scanning apparatus according to disposed claims 2, wherein in any one of 4 between said suction means and the main scanning drum. The suction means has a guide plate for guiding the flow of air,
The guide plate includes a first opening through which the air flow generated by the first blowing nozzle is guided and a second opening through which the air flow generated by the second blowing nozzle is guided. The exposure scanning apparatus according to claim 2 , wherein the exposure scanning apparatus is disposed in the vicinity of the opening so as to form a portion. The suction means is in any one of claims 2 to 6, characterized in that the tip of the main scanning drum side wall of said opening is disposed adjacent to said second spray nozzle The exposure scanning apparatus according to the description. The suction amount of the air suction means, from claim 2, further comprising a first spray nozzle and control means for controlling such that more than blowing amount of air of the second blowing nozzle 7 The exposure scanning apparatus according to any one of the above. Said first spray nozzle, exposure scanning apparatus according to any one of claims 1 to 8, characterized in that blowing air along the rotational direction of the main scanning drum. The suction means, according to any one of claims 1 9, characterized in that the tip of the exposure head side of the wall of the opening is arranged adjacent to the optical axis of the exposure head Exposure scanning device. The suction means, an exposure scanning apparatus according to any one of claims 1 to 10, characterized in that it comprises a tubular member having a cross-sectional area is substantially constant.

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