JP4296456B2 - Image printing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a line exposure head that sets the exposure amount for each pixel of an image and exposes the photographic paper in a line extending in the main scanning direction, and the photographic paper exposed to the line exposure head via the exposure position. An exposure nipping and conveying roller for nipping and conveying in the sub-scanning direction intersecting with the main scanning direction, and a supply-side nipping and conveying roller for nipping and conveying the photographic paper and supplying the photographic paper to the exposing nipping and conveying roller are provided. The present invention relates to an image printing apparatus.
[0002]
[Prior art]
Such an image printing apparatus prints an image such as a photographic image on a photographic paper. A so-called digital printer in which an image is formed on a photographic paper by a line exposure head with an exposure amount set for each pixel of the image. It is a device called.
This line exposure head does not expose the image data to be printed on the photographic paper at once, but sequentially exposes the image data divided into a number corresponding to the exposure range of the line exposure head, One photographic paper is exposed by conveying the photographic paper in the sub-scanning direction intersecting (generally orthogonal) to the main scanning direction by the nipping and conveying rollers for exposure.
[0003]
[Problems to be solved by the invention]
Therefore, in order to produce a print that is faithful to the image data, it is necessary to stably convey the photographic paper. Conventionally, however, the stable conveyance of the photographic paper is not sufficient, and streaky unevenness occurs in the printed image. In some cases, the image quality deteriorates.
The present invention has been made in view of the above circumstances, and an object thereof is to improve print image quality.
[0004]
[Means for Solving the Problems]
By providing the structure according to claim 1, the supply-side nipping / conveying roller for nipping and conveying the exposure nipping / conveying roller and the photographic paper and supplying the printing paper to the nipping / conveying roller for exposure is controlled by the conveyance control means. Before and after the exposure start end of the photographic paper transported by the nipping and transporting roller for exposure reaches the exposure position by the line exposure head. In addition, the supply-side nipping and conveying roller is controlled to be switched from the pressure-bonding conveyance state to the pressure-release state.
This is because when the photographic paper is conveyed by both the supply-side nipping and conveying rollers and the exposure nipping and conveying roller, the exposure nipping and conveying rollers and the supply-side nipping are used during the exposure operation of the photographic paper. The state in which the photographic paper is transported by both the transport rollers is switched to a state in which the photographic paper is transported only by the nipping and transporting roller for exposure, and the transport of the photographic paper is slightly unstable due to the variation of the transport load due to this switching. Based on the knowledge that the print image quality will be deteriorated by this, when the photographic paper is exposed by the line exposure head, it can be conveyed with sufficiently suppressed influence of the supply side nipping and conveying roller It is.
Therefore, the photographic paper being exposed can be stably conveyed, and the print image quality can be improved.
[0005]
In addition, by providing the configuration according to claim 2, the supply-side nipping and conveying roller is switched from the pressure-conveying and conveying state to the pressure-released state, and the photographic paper is conveyed only by the exposure nipping and conveying roller. Continue rotating.
That is, when the rotation of the supply side nipping / conveying roller is stopped when the supply side nipping / conveying roller is switched to the pressure release state, the contact between the conveying and moving photographic paper and the stopped roller causes a slight change in the photographic paper. Since the photographic paper conveyance becomes slightly unstable due to the load, the rotation of the photographic paper can be made more stable by continuing the rotation operation even after the pressure release state is released, and the print image quality is improved. Further improvement can be achieved.
[0006]
In addition, by providing the configuration according to claim 3, the supply-side nipping and conveying roller is switched from the pressure-conveying and conveying state to the pressure-released state, and the printing paper is conveyed only by the exposure nipping and conveying roller. The rotation operation is continued so that the peripheral speed substantially coincides with the peripheral speed of the nipping and conveying roller for exposure.
Therefore, the force acting on the transporting photographic paper can be further reduced, the transport of the photographic paper can be further stabilized, and the print image quality can be further improved.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an image printing apparatus of the present invention will be described with reference to the drawings.
The image printing apparatus IP shown in FIG. 1 automatically exposes photographic paper that has been cut to a print size corresponding to each image, develops the exposed photographic paper, and automatically sends it out after drying. Do it.
The photographic paper 1 is stored in a roll form in a photographic paper magazine 1M loaded in the upper part of the casing of the image printing apparatus IP, and is drawn out into the main body of the image printing apparatus IP by a number of nipping and conveying conveyance rollers.
[0008]
In the casing of the image printing apparatus IP, a cutter 3 that cuts the photographic paper 1 drawn from the photographic paper magazine 1M into a print size corresponding to each image, and a line exposure head that exposes the image on the photographic paper 1 12 and a plurality of development processing rods for developing the photographic paper 1 exposed by the line exposure head 12 and a drying unit dr for drying the photographic paper 1 developed by a drying heater or blower. A development processing unit de and a transport unit TM for transporting the cut photographic paper 1 to the development processing unit de through the exposure position EP by the line exposure head 12 are provided.
The photographic paper 1 discharged out of the housing from the discharge port 4 of the drying unit dr falls on the transverse feed conveyor 5, is conveyed to the sorter 6, and is sorted for each order.
[0009]
The line exposure head 12 employs a so-called PLZT print head in which minute light shutters are arranged in a line using the polarization characteristics of PLZT, and the exposure position EP is set for each pixel of the image on the photographic paper 1 being conveyed. The exposure amount is set to, and the photographic paper is exposed in a line extending in the main scanning direction. Accordingly, the line exposure head 12 sequentially switches and exposes an image portion of a part of the width of the image to be printed in the photographic paper transport direction (specifically, a width corresponding to one pixel). As the exposure format of the line exposure head 12, in addition to the PLZT system described above, a state in which a large number of micromirrors are driven to swing for each mirror and a light beam is irradiated to the photographic paper 1 for each pixel. The so-called DMD method in which the image is exposed to the photographic paper 1 by switching to a state in which the light is stopped, or the fluorescent printing method in which minute fluorescent elements are arranged in a line may be used.
[0010]
The image exposed by the line exposure head 12 is mainly an image of a photographic film read by a film scanner (not shown), and the main body control of the image printing apparatus IP is performed based on image information input from the film scanner. The unit MC sets an exposure time for each pixel of the line exposure head 12, and causes the line exposure head 12 to perform an exposure operation on the photographic paper 1 under the set conditions. In addition to the image information from the film scanner described above, the image printing apparatus IP of the present embodiment can also take an image photographed by a so-called digital camera and expose it to the photographic paper 1.
[0011]
As shown schematically in FIG. 2, the transport means TM develops the transport path and supplies and transports the photographic paper 1 to the exposure position EP by the line exposure head 12, and the photographic paper 1 at the exposure position EP. An exposure conveyance unit B that conveys the image, a pre-sorting holding unit C that temporarily holds the photographic paper 1 that has been exposed by the line exposure head 12, and the photographic paper 1 that has been conveyed in a single row into a plurality of conveyance rows. A sorting device D for sorting, an alignment transport unit E that transports the photographic paper 1 to a plurality of transport rows in the transport lateral width direction at the same time, and a development transport unit F that transports the photographic paper 1 in the development processing unit de are provided. Is configured. The transport path length in the pre-sorting holding unit B, the sorting device C, and the alignment transport unit D is the longest in the transport direction of the photographic paper 1 handled by the image printing apparatus IP, that is, in the present embodiment, a so-called panorama. The length is set so as to hold the photographic paper 1 having the size.
[0012]
The supply conveyance unit A supplies and conveys the photographic paper 1 selectively drawn from either one of the two photographic paper magazines 1M as described above to the exposure conveyance unit B. For this purpose, the cutter 3 and the exposure unit are used. Between the conveyance unit B, four supply-side nipping and conveying rollers 2 and an electric motor M1 that integrally drives the four supply-side nipping and conveying rollers 2 are provided, and convey the photographic paper 1 in a single row. The supply conveyance section A is provided with an upstream end sensor 19a near the conveyance upstream end and a downstream end sensor 19b near the conveyance downstream end, and detects the presence or absence of the photographic paper 1, respectively. Each of the four supply-side nipping and conveying rollers 2 is composed of a pair of idle pressure roller 2b that is driven to move toward and away from the driving roller 2a by a driving mechanism 2a and a cam mechanism (not shown). The driving roller 2a and the free-pressing pressure roller 2b are configured to be switchable between a pressure-conveying state in which the photographic paper 1 is pressure-bonded and conveyed and a pressure-release state in which the pressure-bonding is released.
[0013]
In the exposure conveyance unit B, the nipping and conveying rollers 10 and 11 for exposure are arranged on the upstream side and the downstream side of the photographic paper conveyance path with the exposure position EP by the line exposure head 12 interposed therebetween. Are driven by a single electric motor M2. An upstream sensor 16a for detecting the presence or absence of the photographic paper 1 is provided at a position slightly downstream of the upstream side of the installation position of the upstream holding and conveying roller 10 for the exposure. A downstream sensor 16b that detects the presence or absence of the photographic paper 1 is provided at a position slightly downstream in the transport direction.
Although the detailed explanation is omitted, the nipping and conveying rollers 10 and 11 for exposure are also different in shape from the driving roller and a cam mechanism (not shown) in the direction of approaching and separating from the driving roller in the same manner as the supply side holding and conveying roller 2. It is composed of a pair of free-running pressure-bonding rollers that are driven to move to each other, and can be switched between a pressure-carrying conveyance state in which the photographic paper 1 is pressure-bonded and conveyed by the driving roller and the idle pressure-bonding roller, and a pressure-release state in which the pressure-bonding is released. It is configured. By switching between the pressure-carrying conveyance state and the pressure-release state of each of the exposure nipping / conveying rollers 10, 11, the photographic printing paper 1 is conveyed and driven only by the upstream exposure nipping / conveying roller 10; It is sequentially switched between a state in which the photographic paper 1 is transported by both the transport roller 10 and the downstream exposure nipping and transporting roller 11 and a state in which the photographic paper 1 is transported only by the downstream exposure nipping and transporting roller 11. The photographic paper 1 is conveyed while an image is exposed by the line exposure head 12. The exposure transport unit B transports the photographic paper 1 in a single row.
[0014]
The pre-distribution holding unit C is configured such that a nipping / conveying belt 14 that nipping and conveying the photographic paper 1 with a pair of endless belts arranged on both sides across the conveyance path of the photographic paper 1 is left and right as viewed in the photographic paper conveying direction. An electric motor M3 that is arranged side by side and that integrally drives the two sandwich conveying belts 14 is provided, and a conveyance roller 13 (not shown in FIG. 2) is provided at a bent portion of the conveyance path of the photographic paper 1. It has been. Further, an upstream end sensor 15a is installed near the upstream conveyance end of the pre-sorting holding unit C, and a downstream end sensor 15b is installed near the downstream downstream end of the conveyance to detect the presence or absence of the photographic paper 1. The pre-sort holding unit C also transports the photographic paper 1 in a single row.
[0015]
The sorting device D includes a conveyor unit CU and a slide driving device SD that moves and drives the conveyor unit CU in the conveyance lateral width direction.
In the conveyor unit CU, nipping and conveying belts 18 having endless belts arranged on both sides across the conveying path of the photographic paper 1 are arranged in three rows in the conveying width direction. An electric motor M4 for driving is provided.
The slide drive device SD is configured to include a screw shaft 21 that feeds the support frame of the conveyor unit CU in the conveyance lateral width direction, and a slide motor M5 that drives the screw shaft 21.
The conveyor unit CU is configured to convey the photographic paper 1 in two conveyance rows. Near the conveyance downstream end of each conveyance row in the conveyor unit CU, printing in the right conveyance row as viewed in the photographic paper conveyance direction. A first downstream end sensor 22a for detecting the presence / absence of the paper 1 and a second downstream end sensor 22b for detecting the presence / absence of the photographic paper 1 in the left conveyance row as viewed in the photographic paper conveyance direction are installed.
[0016]
The aligning and conveying unit E includes five first to fifth nipping and conveying belts 23a to 23e that nipping and conveying the photographic paper 1 with a pair of endless belts arranged on both sides of the conveying path of the photographic paper 1. These are arranged side by side in the photographic paper conveyance width direction.
Among the first to fifth sandwiching and transporting belts 23a to 23e, the first and second sandwiching and transporting belts 23a and 23b are driven by the first transporting motor M6, and the central third sandwiching and transporting belt 23c is for the second transporting. Driven by the motor M7, the fourth and fifth nipping and conveying belts 23d and 23e are driven by the third conveying motor M8. The first to third transport motors M6, M7, and M8 are all configured by electric motors. With this configuration, the alignment transport unit E can transport the photographic paper 1 in three transport rows and independently in each row.
Near the conveyance downstream end of each conveyance column in the alignment conveyance unit E, first to third downstream end sensors 28a, 28b, 28c for detecting the presence or absence of the photographic paper 1 in each conveyance column are provided.
As shown in FIG. 1, the development conveyance unit F conveys the photographic printing paper 1 by the conveyance roller 36, and includes three conveyance rows like the alignment conveyance unit E.
[0017]
As shown in FIG. 3, the supply conveyance unit A, the conveyance conveyance unit A, the exposure conveyance unit B, the pre-distribution holding unit C, the distribution device D, and the alignment conveyance unit E are respectively a supply conveyance control unit C1, an exposure conveyance control unit C2, The conveyance control is performed by the holding unit conveyance control unit C3, the sorting device control unit C4, and the alignment conveyance control unit C5. A control signal from the main body control unit MC of the image printing apparatus IP is input to each control unit.
The control operation of the supply conveyance control unit C1 and the exposure conveyance control unit C2 among the controls by these control units will be described. The supply conveyance control unit C1 detects the front end of the photographic paper 1 conveyed by the upstream end sensor 19a. Then, the process shown in the flowchart of FIG. 4 for starting the process is started, and the exposure conveyance control unit C2 starts the process shown in the flowchart of FIG. 5 when the main body control unit MC is instructed to start the exposure of the image. Start.
[0018]
When the photographic paper 1 is conveyed from the upstream side, the supply conveyance unit A is illustrated in FIG. 6A schematically illustrating the conveyance mode until the downstream end sensor 19b detects the front end of the photographic paper 1. Then, the supply side nipping and conveying roller 2 nipping and conveying the photographic paper 1 in the pressure-conveying and conveying state (steps # 1 and # 2), and waits until a conveyance start command is received from the exposure conveyance control unit C2 (steps # 3 and # 4). ).
When exposure start is instructed from the main body control unit MC, the exposure transfer control unit C2 transmits a transfer start command to the supply transfer control unit C1 (step # 11 in FIG. 5).
Receiving this conveyance start command, the supply conveyance control unit C1 resumes conveyance and maintains the pressure conveyance state until a pressure bonding signal is received from the exposure conveyance control unit C2 (steps # 5 and # 6 in FIG. 4). At this time, the conveyance speed of the photographic paper 1 by the supply-side nipping / conveying roller 2 is set so that the peripheral speed of the supply-side nipping / conveying roller 2 and the peripheral speed of the exposure nipping / conveying rollers 10 and 11 are substantially matched. Is substantially the same as the conveyance speed in FIG.
[0019]
On the other hand, in the exposure conveyance control unit C2, when the upstream sensor 16a detects the front end of the photographic paper 1, the upstream exposure nipping and conveying roller 10 is switched from the pressure-release released state to the pressure-carrying conveyance state and the pressure-sensitive conveyance of the photographic paper 1 is carried out. At the same time, a pressure-bonding signal is transmitted to the supply and conveyance control unit C1 to notify that the exposure nipping and conveying roller 10 has started the pressure-sensitive conveyance of the photographic paper 1 (steps # 12, # 13, and # 14). This transmission timing is set so that transmission is performed before the exposure start end of the photographic printing paper 1 conveyed by the upstream holding and conveying roller 10 for exposure reaches the exposure position EP.
[0020]
The supply conveyance control unit C1 that has received the pressure signal switches the supply side clamping conveyance roller 2 from the pressure conveyance state to the pressure release state (step # 7). Therefore, before the exposure start end of the photographic paper 1 conveyed by the exposure nipping / conveying roller 10 reaches the exposure position EP, the supply-side nipping / conveying roller 2 is switched from the pressure conveying state to the pressure releasing state. The supply transport control unit C1 and the exposure transport control unit C2 constitute a transport control unit TC that switches the supply-side nipping transport roller 2 between a pressure-bonding transport state and a pressure-bonding release state.
Further, even after the supply side nipping / conveying roller 2 is switched from the crimping conveyance state to the pressure release state as described above, the rotation operation by the drive of the electric motor M1 is maintained, and the peripheral speed of the supply side nipping / conveying roller 2 is increased. The state that substantially matches the peripheral speed of the nipping and conveying roller 10 for exposure is maintained.
[0021]
In the exposure conveyance section B that has completely taken over the conveyance of the photographic paper 1 from the supply conveyance section A, the upstream exposure nip conveyance roller 10 and the downstream exposure nip conveyance roller according to the conveyance distance of the photographic paper 1 as described above. 11 is switched and transported (steps # 15 to # 18 in FIG. 5). During this conveyance, the line exposure head 12 exposes an image to the photographic paper 1 that is conveyed with the exposure EP under the control of the main body control unit MC. When the downstream sensor 16b of the exposure transport unit B detects the completion of the passage of the photographic paper 1 (step # 19), the process is repeated after waiting for the next exposure start command.
Note that the length of the photographic paper 1 from the front end of the photographic paper 1 to the position of the cutter 3 corresponds to a print size corresponding to a predetermined exposure image while the photographic paper 1 is being conveyed in the supply conveyance unit A. When the length is reached, the supply conveyance control unit C1 is interrupted to temporarily stop the photographic paper 1, and the cutter 3 is operated to cut the photographic paper 1.
[0022]
The photographic paper 1 passing through the exposure conveyance unit B while being exposed by the line exposure head 12 is sent to the pre-sorting holding unit C, and in the pre-sorting holding unit C, one of the two conveyance rows of the sorting device D is printed. If the paper 1 can be received, the received photographic paper 1 is sent as it is to the conveyance row of the pre-sort holding unit C. If the paper 1 cannot be received, the downstream end sensor 15b detects the front end of the photographic paper 1. At the same time, the conveyance of the photographic paper 1 is stopped.
In the sorting device D, in each transport row, the first downstream end sensor 22a or the second downstream end sensor 22b stops transporting as the front end of the photographic paper 1 is detected, and the slide drive device SD performs two rows. Is moved to a position along any two of the three conveyance rows of the alignment conveyance unit E, and the photographic paper 1 received from the pre-sorting conveyance unit C is distributed to the three conveyance columns.
[0023]
The photographic paper 1 distributed from the two transport rows of the sorting device D to the three transport rows of the alignment transport unit E is sent to the first to third downstream end sensors 28a to 28c of each transport column of the alignment transport unit E. Based on the detection information, each conveyance row is stopped. As a general rule, when the photographic papers 1 are arranged in all three conveyance rows, conveyance toward the developing conveyance unit F is started at the same time.
[0024]
[Another embodiment]
Hereinafter, other embodiments of the present invention will be listed.
(1) In the above embodiment, the case where four supply side nipping and conveying rollers 2 are provided is illustrated, but three or less or five or more may be provided.
(2) In the above embodiment, the supply side nipping and conveying roller 2 is driven to move the idle pressure roller 2b to switch between the pressure conveyance state and the pressure release state. However, the drive roller 2a and the idle pressure roller 2b Both of them may be driven to switch between the pressure-carrying conveyance state and the pressure-bonding released state, and the supply side nipping and conveying roller 2 may be configured not to contact the photographic paper 1 in the pressure-released state.
[Brief description of the drawings]
FIG. 1 is a schematic overall configuration diagram of an image printing apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a conveying unit according to the embodiment of the present invention. FIG. 4 is a flowchart according to the embodiment of the present invention. FIG. 5 is a flowchart according to the embodiment of the present invention. FIG. 6 is an operation explanatory diagram according to the embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 Printing paper 2 Supply side clamping conveyance roller 10 Exposure clamping conveyance roller 12 Line exposure head TC Conveyance control means

Claims (3)

A line exposure head that sets the exposure amount for each pixel of the image and exposes the photographic paper in a line extending in the main scanning direction, and the photographic paper exposed to the line exposure head passes through the exposure position in the main scanning direction. An image printing apparatus provided with an exposure nipping / conveying roller for nipping and conveying in the sub-scanning direction intersecting with and a supply-side nipping / conveying roller for nipping and conveying the photographic paper and supplying the photographic paper to the exposure nipping / conveying roller There,
The nipping and conveying roller for exposure and the supply-side nipping and conveying roller are configured to be switchable between a pressure-conveying state in which the photographic paper is pressure-bonded and conveyed and a pressure-release state in which the pressure-bonding is released, A conveyance control means for switching and controlling the crimp release state is provided,
The conveyance control unit moves the supply-side nipping / conveying roller from the pressure-conveying conveyance state to the pressure-bonding release state before the exposure start end of the photographic paper conveyed by the exposure nipping / conveying roller reaches the exposure position. An image printing apparatus configured to perform switching control. 2. The image printing apparatus according to claim 1, wherein the supply-side nipping / conveying roller is configured to continue the rotation operation after switching from the pressure-bonding conveyance state to the pressure-bonding release state. 3. The image according to claim 2, wherein the supply-side nipping / conveying roller is configured to be operated to rotate so that a peripheral speed substantially coincides with a peripheral speed of the exposure nipping / conveying roller after switching to the pressure-bonding release state. Printing device.

Images