JP3595229B2 - Drawing equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drawing apparatus that fixes an image recording medium on which an image is recorded by a photosensitive action, a heat-sensitive action, or the like to an outer peripheral surface of a recording drum, and performs drawing on the photosensitive recording medium.
[0002]
[Prior art]
2. Description of the Related Art Various drawing apparatuses are used to perform drawing by irradiating light to an image recording medium such as a photosensitive material. In a drum type drawing apparatus, an image recording medium is mounted on a recording drum rotatable in a main scanning direction, and a recording head having a laser diode or the like moves in a sub-scanning direction parallel to a rotation axis of the recording drum to expose the recording medium. Perform drawing on a recording medium.
[0003]
FIG. 7 is a schematic side view of a recording drum 110 of a conventional drawing apparatus. The recording drum 110 is rotatably held with respect to the side portion 195. A printing plate 120 is mounted on the recording drum 110 as an image recording medium. On the outer peripheral surface of the recording drum 110, a front end clamp 130 for fixing one end of the printing plate 120 is fixed, and a rear end clamp 160 for fixing the rear end of the printing plate 120 is detachably attached. The front end clamp 130 opens and closes when one end thereof is pressed by a release pin 171 that expands and contracts from the front end clamp pressing device 170. The rear end clamp 160 is normally held by a holding pin 181 of the rear end clamp holding device 180. When the rear end of the printing plate 120 on the recording drum 110 faces the holding device 180, the rear end clamp 160 is moved from the holding pin 181 to the recording drum 110, and engages with a clamp groove 111 described later to engage the recording drum 110. Fixed to the surface. The recording head 190 draws an image on the printing plate 120 by irradiating the printing plate 120 with a laser beam modulated by an image signal.
[0004]
FIG. 8 is a perspective view of the recording drum 110. As shown in FIG. 8, on the outer peripheral surface of the recording drum 110, a plurality of circumferentially extending clamp grooves 111 are formed. On the outer peripheral surface of the recording drum 110, a plurality of front end clamp fixing plates 130 and a plurality of rear end clamps 160 are provided.
[0005]
The plurality of front end clamps 130 are arranged along the axial direction of the recording drum 110 and are fixed to the outer peripheral surface of the recording drum 110. On the other hand, the plurality of rear end clamps 160 are arranged along the axial direction of the recording drum 110, and are respectively mounted on the outer peripheral surface of the recording drum 110 so as to be movable in the circumferential direction along the clamp grooves 111.
[0006]
FIG. 9 shows the back surface (the surface facing the printing plate 120) of the front end clamp 130. FIG. The front end clamp 130 includes a plate fixing plate 131 having six ribs 136, a spring fixing pin 135 for fixing a spring for urging the plate fixing plate 131, and the plate fixing plate 131 so as to penetrate the rib 136. , A bearing 140 for supporting the shaft 141 on the surface of the recording drum 110, a spacer 142 for holding the shaft 141 on the bearing 140, and a bolt 143.
[0007]
FIG. 10 is a cross-sectional view of the front end clamp 130 cut at the center in the longitudinal direction. As shown in this figure, the plate fixing plate 131 is rotatably held around a shaft 141, and the other side 131b is provided with a spring (not shown) inserted through a spring fixing pin 135 (see FIG. 9). Therefore, it is urged in a direction away from the surface of the rotating drum 110. When the release pin 171 (see FIG. 7) not shown in the figure presses the other side 131b, the front end clamp 130 rotates counterclockwise to receive the printing plate 120. Thereafter, when the release pin 171 retreats, the plate 120 is fixed between the one side 131a and the surface of the rotating drum 110 by rotating clockwise by the repulsive force of the spring.
[0008]
In order to securely fix the printing plate 120, the printing plate fixing plate 131 presses a portion of the printing plate 120 that is slightly away from the leading end. That is, the leading end region of the plate 120 itself is not pressed by the one side 131a of the plate fixing plate.
[0009]
[Problems to be solved by the invention]
FIG. 11 is a schematic diagram showing a fixed state of the printing plate 120 on the recording drum 110. As described above, a plurality of clamp grooves 111 for movably holding the rear end clamp 160 are formed on the surface of the recording drum 110 in the circumferential direction of the recording drum 110. The portion where the front end clamp 130 presses the printing plate 120 is hatched.
[0010]
Plates 120 of various sizes in the horizontal direction (the axial direction of the recording drum 110) are mounted on the recording drum 110. For this reason, as shown in this figure, the side end portion of the printing plate 120 sometimes gets over the clamp groove 111. This portion is hereinafter referred to as a protruding portion 122 of the printing plate 120, and the rest is referred to as a non-protruding portion 124.
[0011]
Since the leading end region of the printing plate 120 is not pressed, it is not curved along the peripheral surface of the recording drum 110. For this reason, this region has a lower resistance to the external force in the vertical direction than other portions that are in close contact with the peripheral surface of the recording drum 110. Therefore, the projection 122 may fall into the clamp groove 111, and the plate 120 may be deformed so as to undulate in the horizontal direction (the axial direction of the recording drum 110) from the projection 122 to the non-projection 124 (see FIG. 12). ).
[0012]
If the plate 120 is deformed in this way, the laser light emitted from the recording head 190 will not be focused on the surface of the plate 120, and the drawing quality of the plate 120 may be degraded.
[0013]
The present invention has been made to prevent such deformation.
[0014]
Means and effects for solving the problem
In order to achieve such an object, the following configuration has been adopted as means for solving the above-mentioned problems.
[0015]
(1) First invention The drawing apparatus according to the first invention is characterized in that the drum having a recess extending in the circumferential direction is formed, and the axial end of the drum is projected onto the recess. An image recording medium wound on a drum surface, a clamping member for fixing to the drum surface, a drawing device including a drawing unit that performs image recording on the image recording medium, wherein the clamp member, The image recording medium is arranged at a position other than immediately above the concave portion and corresponding to a substantially boundary of the concave portion, and the image recording medium is drummed by pressing an area where the back surface of the image recording medium contacts the periphery of the concave portion from the front surface. A drawing apparatus, wherein an elastic body that bends along a surface is provided.
[0016]
In the drawing apparatus according to the present invention, since the elastic member that bends the image recording medium along the drum surface by pressing the image recording medium around the concave portion is provided on the clamp member, the image recording medium is vertically As a result, the image recording medium does not fall into the concave portion and is not deformed. Since the flatness of the image recording medium is maintained as described above, it is possible to perform drawing on the medium satisfactorily.
[0017]
(2) Second invention In the drawing apparatus according to the second invention, in the drawing apparatus according to the first invention, the concave portion is a groove extending in a circumferential direction of the drum.
[0018]
In this case, a part of the image recording medium does not fall into the groove extending in the circumferential direction of the drum and is not deformed.
[0019]
(3) Third invention In the drawing apparatus according to the third invention, in the drawing apparatus according to the first or second invention, the image recording medium is a printing plate.
[0020]
In this case, the printing plate fixed to the drum surface does not deteriorate the drawing quality due to the plate deformation.
[0021]
(4) Fourth invention
In the drawing apparatus according to a fourth aspect, in the drawing apparatus according to the first aspect, the clamp member presses both an area facing the recess and an area facing the periphery of the recess on the image recording medium. Further, a fixing portion is provided.
[0022]
In this case, the image recording medium can be securely fixed.
[0023]
(5) Fifth invention
A drawing apparatus according to a fifth aspect of the present invention is the drawing apparatus according to the fourth aspect of the present invention, wherein the elastic body is the leading end region itself of the image recording medium, and the fixing portion is from the leading end region in a circumferential direction of the drum. Each of the slightly separated areas is pressed.
[0024]
In this case, the image recording medium can be securely fixed.
[0025]
(6) Sixth invention
A drawing apparatus according to a sixth aspect of the present invention is the drawing apparatus according to the fifth aspect of the present invention, wherein fine irregularities are formed on a side of the fixing portion that contacts the image recording medium.
[0026]
In this case, the holding of the image recording medium can be ensured.
[0027]
(7) Seventh invention
A drawing apparatus according to a seventh aspect of the present invention is the drawing apparatus according to any one of the first to sixth aspects, wherein the elastic body has a surface pressing the image recording medium on a peripheral surface of the drum. The shape is curved so as to follow the curvature.
[0028]
In this case, the image recording medium is fixed in a curved state along the peripheral surface of the drum.
[0029]
Embodiment
FIG. 1 shows a front end clamp 30 according to the present invention. The front end clamp 30 is applied to the recording drum 110 described above with reference to FIGS.
[0030]
The plate fixing plate 31 of the front end clamp 30 includes a substantially horizontal main body portion 31c and six ribs 36 erected on the main body portion 31c. The main body 31c is bent at the front and rear ends to form one side 31a and the other side 31b, respectively. The one side portion 31a presses and fixes the printing plate 120. On the other hand, the back surface of the side portion 31a (the side in contact with the printing plate 120) is subjected to ceramic processing or the like, and has fine irregularities for ensuring the holding of the printing plate 120. A shaft 41 extends through the rib 36. The lateral movement of the shaft 41 is regulated by bolts 43, 43, and the position of the shaft 41 with respect to the plate fixing plate 31 is determined by four spacers 42. The shaft 41 is further provided with two bearings 40. The bearing 40 is fixed at a predetermined position on the surface of the recording drum 110. Two spring fixing pins 35 are erected on the back surface of the other side 31b of the plate fixing plate 31. A spring (not shown) is attached to the fixing pin 35. Two long holes 32 are formed on one side 31a of the plate fixing plate 31, and two rectangular holes 33 are formed on the other side 31b. The long hole 32 is a detection window for an optical sensor for detecting whether the printing plate 120 is reliably pressed by the front end clamp 3.
[0031]
Two elastic bodies 38 and 39 are attached to the one side 31a side of the back surface of the main body 31c of the printing plate fixing plate 31 at the center position in the longitudinal direction. The elastic bodies 38 and 39 are made of rubber or spring.
[0032]
FIG. 2 shows the plate supporting device 7 which is fitted in the clamp groove 111 on the peripheral surface of the recording drum 110 and supports the plate 120 from below. The plate support device 7 includes a lower portion 70 fixed in the clamp groove 111, a bolt 80 fixing the lower portion 70 to the clamp groove 111, and an upper portion 75 slidably joined to the lower portion 70. , And a screw 82 for joining the lower part 70 and the upper part 75.
[0033]
The printing plate support device 7 is a device that supports the printing plate 120 from below by the support surface 78, thereby preventing the printing plate 120 from dropping into the clamp groove 111. 75 can slide away from the lower portion 70.
[0034]
FIG. 3 is a cross-sectional view of the plate fixing plate 31 and its peripheral portion. The plate holding plate 31 is rotatably mounted on the surface of the recording drum 110 by a shaft 41. As shown in this figure, the elastic bodies 38 and 39 have a bottom surface slightly curved so as to follow the curvature of the peripheral surface of the recording drum 110.
[0035]
On the other hand, the plate support device 7 is fixed in the clamp groove 111 such that the upper surface (support surface 78) of the upper portion 75 is at the same height as the surface of the recording drum 110 when the recording drum 110 is stopped. .
[0036]
In this way, the leading end region of the printing plate 120 is fixed in a state of being curved along the peripheral surface of the recording drum 110 by the elastic bodies 38 and 39.
[0037]
Note that the elastic bodies 38 and 39 are not provided in portions that cover the clamp grooves 111. The reason will be described with reference to FIGS.
[0038]
FIG. 4 is a schematic diagram showing a fixed state of the printing plate 120 on the recording drum 110. As described above, a plurality of clamp grooves 111 for movably holding the rear end clamp 160 are formed on the surface of the recording drum 110 in the circumferential direction of the recording drum 110. The portion where the plate holding plate 31 presses the plate 120 is hatched. As shown in this figure, the leading end portion of the printing plate 120 is curved and fixed along the surface of the recording drum 110 by the one side 31a and the elastic bodies 38 and 39. When the printing plate 120 bends in this way, the resistance to the external force in the vertical direction becomes stronger than in a state where the printing plate 120 is not bent. In this case, since the protrusion 122 does not sink into the clamp groove 111, flatness over the entire length of the printing plate 120 is secured (see FIG. 5).
[0039]
The elastic bodies 38 and 39 are not disposed immediately above the clamp groove 111. This is to prevent the printing plate 120 from being pushed into the clamp groove 111 by the elastic members 38 and 39. That is, although the tip region of the printing plate 120 is curved, the resistance to the external force in the vertical direction is improved. However, when pressed by the elastic bodies 38 and 39, the protruding portion 122 is moved to the clamp groove as shown in FIG. This is because there is a risk of minute deformation toward the inside.
[0040]
The elastic bodies 38 and 39 may be provided in the vicinity of the clamp groove 111, and need not be provided over the entire length of the plate pressing plate 131 in the longitudinal direction.
[0041]
As described above, the front end clamp 31 for pressing the front end of the printing plate 120 has been described as an example. However, the present invention can be applied to a rear end clamp.
[Brief description of the drawings]
FIG. 1 is a view showing a back surface of a front end clamp according to an embodiment of the present invention.
FIG. 2 is a perspective view of a plate supporting device used in one embodiment of the present invention.
FIG. 3 is a cross-sectional view of a front end clamp and its peripheral portion according to an embodiment of the present invention.
FIG. 4 is a schematic view showing a state in which a printing plate is pressed by a front end clamp.
FIG. 5 is a schematic diagram showing a relation between a printing plate and an elastic body in one embodiment of the present invention.
FIG. 6 is a schematic view showing a relation between a printing plate and an elastic body according to one embodiment of the present invention.
FIG. 7 is a side view of a main part of a conventional drawing apparatus.
FIG. 8 is a perspective view of a conventional recording drum 110.
FIG. 9 is a rear view of a conventional front end clamp.
FIG. 10 is a sectional view of a conventional front end clamp.
FIG. 11 is a partial cross-sectional view of a rear end clamp 160 in a conventional drawing apparatus.
FIG. 12 is a schematic diagram showing a state of pressing a printing plate by a conventional front end clamp.
[Explanation of symbols]
2 Plate 7 Plate support device 30 Front end clamp (Example)
31 printing plate fixing plate 31a one side portion 31b the other side portion 31c main body portion 32 long hole 33 rectangular hole 35 spring fixing pin 36 rib 38 elastic body 39 elastic body 40 bearing 41 shaft 42 spacer 43 bolt 70 upper portion 71 bottom surface 72 sliding Surface 73 Hole 75 Lower portion 77 Sliding surface 78 Support surface 80 Bolt 82 Screw 110 Recording drum 111 Clamp groove 120 Plate 122 Projection 124 Non-projection 130 Front end clamp 131 Plate fixing plate 131a One side 131b The other side 132 Long hole 133 Rectangular hole 135 Spring fixing pin 136 Rib 140 Bearing 141 Shaft 142 Spacer 143 Bolt 160 Rear end clamp 170 Front end clamp pressing device 171 Release pin 180 Rear end clamp holding device 181 Holding pin 190 Recording head 195 Side part

Claims (7)

A drum formed with a concave portion extending in the circumferential direction ;
An image recording medium wound around the drum surface such that an axial end of the drum projects above the concave portion, a clamp member for fixing the image recording medium to the drum surface;
A drawing unit for performing image recording on the image recording medium, comprising:
The clamp member is disposed at a position other than immediately above the concave portion and substantially corresponding to the boundary of the concave portion, and by pressing a region where the back surface of the image recording medium contacts the periphery of the concave portion from the front surface. A drawing apparatus, comprising: an elastic body that curves the image recording medium along a drum surface. 2. The apparatus according to claim 1, wherein the recess is a groove extending in a circumferential direction of the drum. The drawing apparatus according to claim 1, wherein the image recording medium is a printing plate. The clamp member,
The drawing apparatus according to claim 1, further comprising a fixing unit that presses both an area facing the recess and an area facing the periphery of the recess of the image recording medium . 5. The drawing apparatus according to claim 4, wherein the elastic body presses a front end region of the image recording medium, and the fixing unit presses a region slightly away from the front end region in a circumferential direction of the drum. The drawing apparatus according to claim 5, wherein fine irregularities are formed on a side of the fixing portion that contacts the image recording medium. The drawing apparatus according to any one of claims 1 to 6, wherein the elastic body has a surface pressing the image recording medium curved so as to follow a curvature of a peripheral surface of the drum.

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