JPH09152707A - Rotary drum for image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary drum of an image recorder capable of easily attracting and holding photosensitive films of various sizes. SOLUTION: The rotary drum has plural suction paths 8 (8B3 , 8A2 , 8B2 ) within the thick parts of the cylinder port 1 of the drum. These suction paths 8 are communication and connected respectively discreetly with and to the suction hole 9 groups in the plural suction regions meeting the various sizes of the photosensitive films disposed on the peripheral surface of the drum. The respective suction paths 8 are rearranged for each of the respective suction regions in the flange part 2 of the cylindrical part 1 of the drum and are communicated and connected with and to the plural axial vent paths in the revolving shaft part of the drum via discrete vent pipes 14B3 , 14A2 , 14B2 . The axial vent paths are communicated and connected with and to discrete external vent pipes via rotary hermetic sealing mechanisms. The respective external vent pipes are communicated and connected with and to a vacuum discharge pump via changeover mechanisms of flow passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum type image recording device such as a color scanner for plate making, and more particularly to a structure of a rotary drum on which a photosensitive film is mounted.

[0002]

2. Description of the Related Art As is well known, in this type of image recording apparatus, a photosensitive drum is moved by moving an exposure head along a drum axis while rotating a rotary drum on which the photosensitive film is mounted at high speed. The image is printed by scanning exposure. The rotary drum has a hollow structure, and the inside of the rotary drum is sucked by a vacuum exhaust pump to suck and hold the photosensitive film through a large number of suction holes formed on the circumferential surface of the drum. By the way, there are various sizes of photosensitive films, and when a relatively small size photosensitive film is mounted on a rotary drum, the suction holes on the drum peripheral surface which are not covered with the photosensitive film are different from each other. It is sealed with tape to keep the rotary drum airtight. Since the work of closing the suction hole of the rotary drum every time the size of the photosensitive film is changed is very troublesome, various rotary drum structures that do not require the closing work have been proposed.

For example, the rotary drum disclosed in Japanese Patent Laid-Open No. 62-56071 is divided into a plurality of compartments by a partition plate inside the rotary drum having suction holes formed on its peripheral surface.
By vacuum suctioning each compartment individually according to the size of the photosensitive film, films of various sizes can be suction-held.

Further, in the rotary drum disclosed in Japanese Patent Laid-Open No. 2-291762, the outer peripheral surface of the cylindrical portion is divided into a plurality of suction areas corresponding to the size of the photosensitive film, and each suction area has A suction groove extending to one flange portion of the rotary drum is formed. Each suction groove is connected to a plurality of communication passages formed on the flange portion, and each communication passage is connected to a plurality of suction passages formed on the rotating shaft portion. Each suction path is connected to a vacuum exhaust pump via a flow path switch. By appropriately switching the flow path switching device, a desired adsorption region is operated to adsorb and hold the photosensitive film of various sizes.

[0005]

However, the prior art having such a structure has the following problems. That is, in the former rotary drum, a partition plate is welded to the inner peripheral surface of the drum in order to partition the inside by a partition plate, but such welding work inside the drum is very difficult and the manufacturing cost is high. In addition, there is a problem that the rotating drum is likely to be distorted during welding. Further, this type of rotary drum may be provided with a perforation mechanism for perforating a hole in the photosensitive film that serves as a reference for positioning in a subsequent printing process or the like. Since such a punching mechanism is installed so as to penetrate through the thick part of the cylindrical part of the rotating drum, it is necessary to provide an airtight seal so that vacuum leakage does not occur at the penetrating part, which complicates the structure. To do.

Further, in the latter rotary drum, since the suction grooves formed in the respective suction areas on the drum peripheral surface are led out to the flange portion, each suction area is based on the flange portion of the rotating drum (each It must be set so that the edge of the size photosensitive film reaches the flange. Otherwise, when a photosensitive film is attached to a certain suction area, the suction groove extending from the suction area and reaching the flange is not covered with the photosensitive film, and the exposed suction groove is covered with another film or the like. This is because the need arises. When each suction area is set based on the flange of the rotary drum as described above, when photosensitive films of various sizes are carried into the rotary drum by using a common carrier roller group,
The small-sized photosensitive film is conveyed in a state in which it is close to one side in the conveying roller group. As a result, a non-uniform conveying force is applied to the photosensitive film, the photosensitive film meanders, the film is deformed, and conveyance jamming is likely to occur.

The present invention has been made in view of the above circumstances, and is capable of easily adsorbing and holding photosensitive films of various sizes, and is easy to manufacture without solving the above problems. The main object of the present invention is to provide a rotary drum for a simple image recording device.

[0008]

The present invention has the following configuration in order to achieve the above object. That is, the invention according to claim 1 is a rotary drum of an image recording apparatus for adsorbing and holding a photosensitive film on a rotating drum, scanning and exposing the photosensitive film while rotating the rotating drum to record an image, In the thick portion of the drum cylindrical portion of the rotary drum, a plurality of suction passages are formed along the axis thereof, and each suction passage has various sizes of the photosensitive film provided on the peripheral surface of the drum cylindrical portion. Are individually connected to the suction hole groups in the plurality of suction regions corresponding to each other, and the suction passages are grouped for each suction region on the end surface portion of the drum cylindrical portion, and the individual suction pipes are provided. It is connected to a plurality of shaft ventilation passages in the drum rotating shaft portion, and each shaft ventilation passage is connected to an individual external ventilation pipe via a rotary airtight sealing mechanism, and each external ventilation pipe is connected to a passage switching mechanism. Evacuation Characterized in that it is communicatively connected to stage.

According to a second aspect of the present invention, in the rotary drum of the image recording apparatus according to the first aspect, ribs extending radially from the rotation shaft core and connected to the inner peripheral surface of the drum are integrated in the rotary drum. Has been formed.

[0010]

The operation of the present invention is as follows. According to the first aspect of the invention, the suction holes in the suction area of the drum peripheral surface on which the photosensitive film is mounted are provided as the vacuum exhaust means according to the size of the photosensitive film on which an image is to be recorded. The flow path switching mechanism is switched so as to be connected for communication. As a result, the suction holes in the suction area are communicated with the vacuum evacuation means through the specific suction passage, the ventilation pipe, the shaft ventilation passage and the external ventilation pipe in the thick portion of the drum cylindrical portion, so that the suction The area is in an operating state where the photosensitive film can be adsorbed and held.

According to the invention described in claim 2, since the rib is formed in the rotary drum, the rotary drum is deformed during rotation even if a heavy attachment mechanism is attached to the peripheral surface of the rotary drum. Is suppressed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view showing a main configuration of a rotary drum of an image recording apparatus according to the present invention, FIG. 2 is a development view of a peripheral surface of the rotary drum, FIG. 3 is a cross sectional view of the rotary drum, and FIG. 4 is a rotary drum. FIG. 5 is a partially cutaway perspective view of one end side of FIG. 5, FIG. 5 is a horizontal cross-sectional view of a flange portion of the rotary drum, and FIG. 6 is a vertical cross-sectional view of the periphery of the rotary shaft portion of the rotary drum.

The rotary drum according to the present embodiment is provided with a drum cylindrical portion 1 for adsorbing and holding photosensitive films F of various sizes (here, B3, A2, B2 sizes), and one end side of this drum cylindrical portion 1 is ventilated. A ring-shaped flange portion 2 having a built-in passage is attached. As shown in FIG. 6, a rotary shaft portion 3 provided with a shaft ventilation passage is attached to the shaft core of the drum cylindrical portion 1, and one end of the rotary shaft portion 3 is led out from a central hole of the flange portion 2. The rotary shaft portion 3 is connected to the output shaft of the stepping motor 4. A rotary airtight seal mechanism 5 is attached to the rotary shaft portion 3, and the rotary airtight seal mechanism 5 and the vacuum exhaust pump 6 are connected to each other through external ventilation pipes 7 _B3 , 7 _A2 , 7 _B2 . Hereinafter, the configuration of each unit will be described in detail.

As shown in FIGS. 1 to 3, in the thick portion of the drum cylindrical portion 1, ten suction passages 8 are formed in the circumferential direction of the drum along the axis thereof. Each suction passage 8 is open at one end face side where the flange portion 2 is attached, and is closed at the other end side. Of the suction paths 8, three suction paths 8 _B3 are set to be distributed on the peripheral surface of the drum cylindrical portion 1 with reference to the substantially center CL of the drum length, and are set as suction areas of the B3 size photosensitive film (in FIG. 2). Corresponding to the area B3) and is connected to and connected to a group of suction holes 9 formed in the suction area B3. The other three suction paths 8 _A2 similarly correspond to the suction area (area indicated by reference symbol A2 in FIG. 2) of the A2 size photosensitive film, which is set by dividing the center CL as a reference. It is connected to the group of suction holes 9 formed in the area A2.
The remaining four suction passages 8 _B2 correspond to the suction area (area indicated by reference numeral B2 in FIG. 2) of the B2 size photosensitive film, and the suction holes 9 formed in the suction area B2 Connected for communication. The suction area A2 includes a suction area B3, and the suction area B2 includes suction areas B3 and A2.

Adsorption grooves 10 extending in the circumferential direction of the drum are formed in the adsorption areas B3, A2, B2, respectively.
0 is connected to the suction holes 9 in each suction area. The suction grooves 10 in the suction areas B3, A2, B2 are arranged so as not to extend to other suction areas.

In the hollow portion of the drum cylindrical portion 1, ribs 11 extending radially from the rotary shaft core and connected to the inner peripheral surface of the drum are integrally formed with the drum cylindrical portion 1. Drum cylinder 1
In a state where a relatively heavy attachment mechanism such as a film pressing mechanism 12 and a hole punching mechanism 13 described later is attached to
If the rotary drum is driven to rotate at a high speed during image recording, the drum cylindrical portion 1 may be deformed by the rotational centrifugal force of these accessory mechanisms. Therefore, by disposing the ribs 11 in the drum cylindrical portion 1 as described above, the deformation of the drum cylindrical portion 1 is prevented. The drum cylindrical portion 1 on the side opposite to the side on which the film pressing mechanism 12 and the perforating mechanism 13 are provided.
Is thicker than other portions.
This roughly balances the weight with the above-mentioned accessory mechanism.

The drum cylindrical portion 1 as described above is preferably integrally molded with an extrusion molding die using aluminum alloy or the like from the viewpoint of manufacturing cost. The thick portion of the drum cylindrical portion 1, the suction passages 8 and the ribs 11 provided therein can be formed in one step by extrusion molding.

The film pressing mechanism 12 is for mechanically holding the leading end portion of the photosensitive film carried in by a carrying roller group (not shown), and is rotatably supported on the peripheral surface of the drum cylindrical portion 1. A plurality of pressing pieces 12b corresponding to various film sizes of the photosensitive film are inserted and fixed on the elongated support shaft 12a. Although not shown, one end of the support shaft 12a is bent into an L shape,
The pressing piece 12b is opened and closed by rotating the support shaft 12a by applying an eccentric cam to the bent portion.

The perforating mechanism 13 is for perforating a small hole which serves as a positioning reference in a subsequent printing process or the like in the end face portion of the photosensitive film mounted on the rotary drum. As shown in FIG. 3, the punch 13b penetrates through the thick portion of the drum cylindrical portion 1 by the air cylinder 13a attached to the inner peripheral surface of the drum cylindrical portion 1, and the die 13c is provided on the drum surface. In cooperation with, it is designed to make small holes in the photosensitive film. In the rotary drum of the present invention, since the suction passage 8 is in the thick portion of the drum cylindrical portion 1, it is not necessary to maintain the airtightness of the hollow portion of the drum cylindrical portion 1.
Since it is not necessary to hermetically seal the hole forming mechanism 13 penetrating the thick portion of the drum cylindrical portion 1, the rotary drum can be easily manufactured.

Next, the flange portion 2 will be described. The flange portion 2 collects ten suction passages 8 that are open at one end surface of the drum cylindrical portion 1 for each suction region B3, A2, B2, and three ventilation pipes 14 (14 _B3 , 14 _A2 , 14 _B2). )
It is for connecting to three shaft ventilation passages in the rotary shaft portion 3 described later via. As shown in FIG. 6, the flange portion 2 includes two ring-shaped plate members 2 made of synthetic resin.
The internal flow paths are formed by airtightly bonding a and 2b. As shown in FIG. 5, the plate member 2a on the drum cylindrical portion 1 side
The internal space formed by the outer wall 15a standing upright along the outer peripheral edge thereof and the inner wall 15b standing upright along the inner peripheral edge thereof is partitioned by the partition wall 15c, and the three internal flow paths 16 are formed.
(16 _B3 , 16 _A2 , 16 _B2 ) are formed. The inner internal flow path 16 _B3 is provided with an intake port 17 _{B3 at} a position corresponding to the suction path 8 _B3 . Intermediate flow path 1
6 _A2 is provided with an intake port 17 _{A2 at} a position corresponding to the suction passage 8 _A2 . In the outer internal flow path 16 _B2 ,
Suction paths 8 _B2 each intake port 17 _B2 at a position corresponding to is opened. Since the intermediate internal flow path 16 _A2 is divided into three regions by the partition wall 15c, these regions are communicated with each other by the communication pipes 18a and 18b arranged on the plate member 2b side (see FIGS. 4 and 5). ). As shown in FIG. 6, there are cylindrical small projections 19 on the rear surface of the plate member 2a at positions corresponding to the respective intake ports 17, and these small projections 19 are stepped openings of the corresponding suction passages 8 of the drum cylindrical portion 1. The flange portion 2 is airtightly connected to the drum cylindrical portion 1 so as to be fitted into the portion.

As shown in FIGS. 4 to 6, the rotary shaft portion 3 is bolted to one end surface of the drum cylindrical portion 1.
Are three axial ventilation passages (20 _B3 , 2
0 _A2 , 20 _B2 ) and the axial ventilation passage 20 _B3 is a ventilation pipe 14 _B3.
To the internal flow passage 16 _B3 of the flange portion 2 via the shaft ventilation passage 2
0 _A2 is the internal flow path 1 of the flange 2 through the ventilation pipe 14 _A2
6 _A2 , the shaft ventilation passage 20 _B2 is connected to the internal flow passage 16 _B2 of the flange portion 2 through the ventilation pipe 14 _B2 , respectively.

As shown in FIG. 6, a rotary shaft portion 3 connected to both end surfaces of the drum cylindrical portion 1 (however, a shaft ventilation passage is formed in the rotary shaft portion opposite to the drum cylindrical portion 1 not shown). (Not shown) is rotatably supported by a bearing 21. The rotary airtight seal mechanism 5 is attached to the rotary shaft portion 3 extending from the bearing 21. The inside of the rotary airtight seal mechanism 5 is divided into three inner spaces 22 _B3 , 22 _A2 , 22 _B2 by a seal member, and the end of the shaft ventilation passage 20 _B3 is in the inner space 22 _B3 and the shaft ventilation passage 20 _A2 . The end is opened to the internal space 22 _A2 , and the end of the shaft ventilation passage 20 _B2 is opened to the internal space 22 _B2 .

The internal space 22 _B3 of the rotary airtight seal mechanism 5 is directly connected to the internal space 22 _B via the external ventilation pipe 7 _B3.
A2 is connected to the vacuum exhaust pump 6 via the external ventilation pipe 7 _A2 and the electromagnetic valve 23 _A2 , and the internal space 22 _B2 is connected to the vacuum exhaust pump 6 via the external ventilation pipe 7 _B2 and the electromagnetic valve 23 _B2 .

The operation of the rotary drum of the image recording apparatus constructed as above will be described below. The B3, A2, and B2 size photosensitive films to be image-recorded by the apparatus of this embodiment are carried into the rotary drum by a common carrier roller group (not shown). As described with reference to FIG. 2, since the suction areas B3, A2, B2 on the drum peripheral surface for suction-holding the photosensitive film of each size are evenly distributed to the left and right with the center CL in the drum axis direction as a reference. The center lines of the photosensitive films of each size being conveyed are substantially coincident with each other. That is, since the photosensitive film of each size is carried in through the center of the conveying roller group, the photosensitive film receives the propulsive force evenly from the conveying roller group regardless of its size. Therefore, there is no fear of meandering which is likely to occur when being conveyed by one side of the conveying roller group, and the photosensitive film of each size can be smoothly conveyed.

Now, when an image is recorded on the smallest B3 size photosensitive film, the solenoid valves 23 _A2 , 2 shown in FIG.
Both 3 _B2 are closed, and the rotary drum is evacuated only through the external ventilation pipe 7 _B3 . As a result, suction paths 8 _A2 and 8 _B2
Is not evacuated through the suction passage 8 _B3 communicating with the external ventilation pipe 7 _B3 through the shaft ventilation passage 20 _B3 of the rotary shaft portion 3 and the internal passage 16 _B3 of the flange portion 2. Is performed, only the suction area B3 on the drum peripheral surface is activated.

When an image is recorded on an intermediate A2-size photosensitive film, the solenoid valve 23 _A2 is opened and the solenoid valve 23 _B2 is closed. As a result, the rotary drum is evacuated through the external ventilation pipes 7 _B3 and 7 _A2 . As a result, the vacuum exhaust is not performed through the suction passage 8 _B2 ,
External ventilation pipes 7 _B3 through the axial ventilation passages 20 _B3 , 20 _{A2 of the} rotary shaft portion 3 and the internal flow passages 16 _B3 , 16 _A2 of the flange portion 2,
Since vacuum exhaust is performed through the suction passages 8 _B3 and 8 _A2 communicating with 7 _A2 , the suction area A2 including the suction area B3 on the drum peripheral surface is activated.

When recording an image on a photosensitive film of the maximum B2 size, both solenoid valves 23 _A2 and 23 _B2 are opened. This allows all external ventilation pipes 7 _B3 , 7 _A2 , 7
_The rotary drum is evacuated via _B2 . As a result, the external ventilation pipes 7 _B3 , 7 _A2 , 7 _B2 are communicated with each other through the shaft ventilation passages 20 _B3 , 20 _A2 , 20 _{B2 of} the rotary shaft portion 3 and the internal flow passages 16 _B3 , 16 _A2 , 16 _B2 of the flange portion 2. All suction channels 8 _B3 ,
Since the vacuum exhaust is performed through 8 _A2 and 8 _B2 , the suction area B2 including the suction areas B3 and A2 on the drum peripheral surface is activated.

As described above, since any one of the suction regions of the drum cylindrical portion 1 is selectively operated according to the size of the photosensitive film on which an image is to be recorded, a small-sized photosensitive film is mounted. Even in this case, it is not necessary to block the peripheral surface of the drum not covered with the photosensitive film with tape or the like.

The photosensitive film conveyed by the conveying roller group is sandwiched by the film pressing mechanism 12 at the leading end thereof, and is inserted into the perforating mechanism 13 to be perforated. Then, the photosensitive film is wound around a predetermined suction area and suction-held while rotating the rotary drum at a low speed by the stepping motor 4 shown in FIG. When the photosensitive film is mounted on the rotary drum, the exposure head (not shown) is moved along the axis of the rotary drum while rotating the rotary drum at a high speed by the stepping motor 4 to print an image on the photosensitive film. .

In the above embodiment, B3, A2, B
Although the description has been given by taking the rotary drum on which the two size photosensitive films are mounted as an example, the present invention is not limited to this and can be applied to various size photosensitive films.

[0031]

As is apparent from the above description, the present invention has the following effects. According to the first aspect of the present invention, the suction path formed in the cylindrical portion of the rotary drum in the axial direction and the suction hole group formed in each suction area of the drum peripheral surface are communicated with each other to form photosensitive members of various sizes. Since it is configured to adsorb and hold the flexible film, it is not necessary to weld a partition plate inside the drum, and the rotary drum can be manufactured relatively easily. Further, since it is not necessary to maintain the airtightness of the hollow portion of the drum, it is not necessary to seal the attachment portion when attaching the punch mechanism or the like through the cylindrical portion of the drum, which facilitates manufacturing. Further, since the suction holes communicating with the suction hole groups formed in the respective suction regions are formed in the thick portion of the drum cylindrical portion, the suction grooves communicating with the suction hole groups are formed along the drum peripheral surface of the rotary drum. It is not necessary to set each suction area with the flange portion as a reference as in the case where the suction area is led out to the flange portion, and each suction area can be set at an arbitrary position on the peripheral surface of the rotary drum.
Then, by setting each suction area with the center of the drum length as a reference, it is possible to smoothly carry the photosensitive films of various sizes sent by the common carrying roller group.

According to the invention described in claim 2, since the rib is formed in the rotary drum, even if a heavy attachment mechanism is attached to the peripheral surface of the rotary drum, the rotary drum is deformed during rotation. It is possible to prevent vibration of the rotating drum which is not preferable for image recording.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a main configuration of an embodiment of a rotary drum of an image recording apparatus according to the present invention.

FIG. 2 is a development view of a peripheral surface of a rotating drum.

FIG. 3 is a cross-sectional view of a rotary drum.

FIG. 4 is a partially cutaway perspective view of one end of the rotating drum.

FIG. 5 is a cross-sectional view of a flange portion.

FIG. 6 is a vertical cross-sectional view around a rotary shaft portion.

[Explanation of symbols]

DESCRIPTION OF _SYMBOLS 1 ... Drum cylinder part 2 ... Flange part 3 ... Rotating shaft part 5 ... Rotating airtight seal mechanism 6 ... Vacuum exhaust pump (vacuum exhaust means) 7 _B3 , 7 _A2 , 7 _B2 ... External ventilation pipe 8 (8 _B3 , 8 _A2 , 8 _B2 ) ... Suction path 9 ... Suction hole 11 ... Rib 14 (14 _B3 , 14 _A2 , 14 _B2 ) ... Ventilation pipe 20 (20 _B3 , 20 _A2 , 20 _B2 ) ... Shaft ventilation path 23 _A2 , 23 _B2 ... Solenoid valve (Flow path switching mechanism)

Claims (2)

[Claims] 1. A rotating drum of an image recording apparatus for adsorbing and holding a photosensitive film on a rotating drum, and performing scanning exposure of the photosensitive film while rotating the rotating drum to record an image, the drum cylinder of the rotating drum. In the thick part of the part, a plurality of suction paths are formed along the axis, and each suction path has a plurality of suctions according to various sizes of the photosensitive film provided on the peripheral surface of the drum cylindrical portion. Each of the suction passages is individually connected to the suction hole group in the area, and each suction path is grouped for each suction area on the end surface portion of the drum cylindrical portion, and a plurality of suction paths are provided in the drum rotation shaft portion through individual ventilation pipes. The shaft ventilation passages are connected to each other, and each shaft ventilation passage is connected to an individual external ventilation pipe via a rotary airtight sealing mechanism, and each external ventilation pipe is connected to a vacuum exhaust means via a flow passage switching mechanism. Been A rotary drum of the image recording apparatus characterized Rukoto. 2. The rotating drum of the image recording apparatus according to claim 1, wherein a rib extending radially from a rotation axis and connected to an inner peripheral surface of the drum is integrally formed in the rotating drum. Rotating drum.