JP7019974B2 - Image forming device and image forming method - Google Patents

Description

The present invention relates to an image forming apparatus and an image forming method.

Conventionally, there are known methods of performing various processes using a head unit. For example, a method of forming an image or the like by a so-called inkjet method of ejecting ink from a print head unit is known. Then, in image formation, a method for improving the image quality of an image formed on a transported object is known.

For example, a method of moving the position of the print head is known in order to improve the image quality. Specifically, first, in a continuous paper printing system, a position change in the lateral direction of the web is detected by a sensor. Next, a method of moving the position of the print head in the lateral direction so as to compensate for the position variation detected by the sensor is known (see, for example, Patent Document 1).

However, in the conventional method, when processing both sides of the object to be transported, there is a problem that the alignment of both sides cannot be performed with high accuracy.

One aspect of the present invention is intended to enable accurate alignment of both sides when processing both sides of an object to be transported.

In order to solve the above-mentioned problems, the image forming apparatus for forming an image on a transported object, which is one aspect of the present invention, is used.
A first detection unit that detects surface information on the first or second surface of the object to be transported, and
A first head unit that forms an image on the first surface of the object to be transported based on the detection result of the first detection unit, and
A second detection unit that detects surface information on the same surface as the first detection unit, and
A second head unit that forms an image on a second surface different from the first surface based on the detection results of the first detection unit and the second detection unit .
A moving unit that moves the first head unit and the second head unit based on the detection result, and
To prepare for.

When both sides of the object to be transported are processed, the alignment of both sides can be performed with high accuracy.

It is a schematic diagram which shows the whole structure example of the transfer apparatus which concerns on one Embodiment of this invention. It is a schematic diagram which shows the structural example of the apparatus which performs the image formation processing which concerns on one Embodiment of this invention. It is a top view which shows the structural example of the apparatus which performs the image formation processing which concerns on one Embodiment of this invention. It is a figure which shows an example of the external shape of the liquid discharge head unit which concerns on one Embodiment of this invention. It is a block diagram which shows the hardware configuration example which realizes the to be delivered detection apparatus which concerns on one Embodiment of this invention. It is an external view which shows an example of the apparatus which realizes the sensor device which concerns on one Embodiment of this invention. It is a functional block diagram which shows an example of the functional structure of the transported object detection apparatus which concerns on one Embodiment of this invention. It is a block diagram which shows an example of the correlation calculation method which concerns on one Embodiment of this invention. It is a figure which shows an example of the search method of the peak position in the correlation calculation which concerns on one Embodiment of this invention. It is a figure which shows the calculation result example of the correlation calculation which concerns on one Embodiment of this invention. It is a block diagram which shows an example of the hardware composition of the control part which concerns on one Embodiment of this invention. It is a block diagram which shows an example of the hardware composition of the data management apparatus which the control part which concerns on one Embodiment of this invention has. It is a block diagram which shows an example of the hardware composition of the image output apparatus which the control part which concerns on one Embodiment of this invention has. It is a timing chart which shows the detection example of the position of the object to be conveyed by the transfer apparatus which concerns on one Embodiment of this invention. It is a timing chart which shows the control example of the processing timing by the transfer apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows the processing example by the transfer apparatus which concerns on one Embodiment of this invention. It is a functional block diagram which shows the functional composition example of the transfer apparatus which concerns on one Embodiment of this invention. It is a schematic diagram which shows the arrangement example of the sensor in the transfer apparatus which concerns on one Embodiment of 2nd Embodiment of this invention. It is a functional block diagram which shows the functional composition example of the transfer apparatus which concerns on one Embodiment of 2nd Embodiment of this invention. It is a schematic diagram which shows the arrangement example of the sensor in the transfer apparatus which concerns on one Embodiment of 3rd Embodiment of this invention. It is a flowchart which shows the processing example by the transfer apparatus which concerns on one Embodiment of 3rd Embodiment of this invention. It is a functional block diagram which shows the functional composition example of the transfer apparatus which concerns on one Embodiment of 3rd Embodiment of this invention. It is a schematic diagram which shows the whole structure example of the apparatus which concerns on a comparative example. It is a figure which shows the example of the deviation amount of the processing position by the apparatus of the comparative example. It is a figure which shows the example of the influence which the eccentricity of a roller has on the deviation amount. It is a schematic diagram which shows the modification of the structure of the apparatus which performs the image formation processing which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the present specification and the drawings, the components having substantially the same functional configuration are designated by the same reference numerals, and duplicate description will be omitted.

Hereinafter, a processing device having a transported object detection device will be described as an example. In this example, the processing device is a transport device that performs a process of discharging a liquid by a head unit with respect to a web which is an example of an object to be transported. Further, in this example, it is assumed that the transport device is an image forming device that forms an image on the web by performing a process of discharging a liquid to the web. Hereinafter, the transport device is an image forming device, the head unit is referred to as a “liquid discharge head unit”, and the position where the liquid lands on the web is referred to as an example of the “processing position”.

<Overall configuration example>
FIG. 1 is a schematic view showing an example of a transport device according to an embodiment of the present invention. For example, the liquid discharged by the liquid discharge head unit is a recording liquid such as water-based or oil-based ink. Further, the transport device 100 transports an object to be transported such as a web 120.

The object to be transported is, for example, a recording medium or the like. In the illustrated example, the transport device 100 ejects a liquid to the web 120 to be transported to form an image. Further, the web 120 is a so-called continuous paper or the like. That is, the web 120 is a roll-shaped paper or the like that can be rolled up. As described above, the transport device 100 is a so-called production printer.

In the following description, an example will be described in which the rollers and the like adjust the tension of the web 120 and the web 120 is conveyed in the direction shown in the drawing (hereinafter referred to as “transport direction 10”). Further, in the following description, the direction orthogonal to the transport direction 10 is defined as the orthogonal direction. Further, in this example, the transport device 100 ejects four color inks of black (K), cyan (C), magenta (M), and yellow (Y) to form an image at a predetermined position on the web 120. It is an inkjet printer.

As shown in the figure, the transport device 100 has two or more devices that perform image formation processing. First, the unwinder 140 that supplies the web 120 is the most upstream. Then, the web 120 is conveyed upstream from the unwinder 140 to the device 10M1 that performs image forming processing by a roller 230 or the like. Then, the device 10M1 that performs the image forming process performs the process on the web 120 by the head unit 210.

Next, after being processed by the device 10M1 that performs the image forming process, the web 120 is conveyed to the device 10M2 that performs the image forming process downstream. The device 10M2 that performs the image forming process also performs the process on the web 120 in the same manner as the device 10M1 that performs the image forming process.

Further, the transport device 100 may have a drying roller 160 or the like as shown in the figure. For example, if there is a drying roller 160, the transporting device 100 can dry the web 120 after the processing is performed by the device 10M1 or 10M2 that performs the image forming process by the drying roller 160. In this way, the drying roller 160 allows the transfer device 100 to reduce the transfer of ink to the transfer roller.

Further, the transport device 100 may have a post-processing device 150 or the like as shown in the figure. The post-processing device 150, for example, performs a winding process, a bookbinding process, and the like downstream after being processed by the device 10M2 that performs an image forming process.

Further, it is desirable that the transport device 100 has a reversing device such as a turn bar 130 as shown in the figure. The turnstile 130 performs a process of turning over the front surface and the back surface of the web 120. Therefore, when the turnstile 130 is installed between the devices 10M1 and 10M2 that perform the image forming process, the transport device 100 can allow the devices 10M1 and 10M2 that perform the image forming process to process different surfaces.

FIG. 2 is a schematic diagram showing a configuration example of an apparatus that performs image formation processing according to an embodiment of the present invention. As shown in the figure, the transport device 100 has a plurality of devices 10M1, 10M2 and turnbars 130 for performing image formation processing, and performs so-called double-sided printing. That is, the device 10M1 that performs the image forming process performs the process of forming an image on the first surface FE1. Then, after the front surface and the back surface of the web are inverted by the turn bar 130, the apparatus 10M2 that performs the image forming process performs the image forming process on the second surface FE2.

As shown in the figure, the apparatus 10M1 that performs the image forming process has four liquid ejection head units 210K1, 210C1, 210M1 and 210Y1 for ejecting inks of four colors. Further, the device 10M2 that performs the image forming process also has four liquid discharge head units 210K2, 210C2, 210M2 and 210Y2.

Each liquid discharge head unit performs a process of discharging liquids of each color to the web 120 transported in the transport direction 10. Further, it is assumed that the web 120 is conveyed by two pairs of nip rollers, rollers 230, and the like arranged for each device. Hereinafter, of the two pairs of nip rollers, the nip roller installed on the upstream side of each liquid discharge head unit of the devices 10M1 and 10M2 that perform image forming processing is referred to as "first nip roller NR1". On the other hand, the nip roller installed on the downstream side of the first nip roller NR1 and each liquid discharge head unit is referred to as "second nip roller NR2". As shown in the figure, each nip roller rotates with the web 120 interposed therebetween. As described above, each nip roller and roller 230 is a motor or the like that conveys the web 120 in the conveying direction 10.

Further, it is desirable that the web 120 is long. Specifically, it is desirable that the length of the web is longer than the distance between the first nip roller NR1 and the second nip roller NR2 of the devices 10M1 and 10M2 that perform the respective image forming processes. Further, the transported object is not limited to the web. That is, the transported object may be a paper that is folded and stored, so-called "Z paper" or the like.

In the overall configuration example shown below, each liquid discharge head unit is installed in the order of black (K), cyan (C), magenta (M), and yellow (Y) from the upstream side to the downstream side. do. The liquid discharge head unit (hereinafter referred to as “black liquid discharge head unit 210K1”) installed on the most upstream side of the device 10M1 that performs image formation processing is used for black (K). The liquid discharge head unit (hereinafter referred to as "cyan liquid discharge head unit 210C1") installed next to the black liquid discharge head unit 210K1 is used for cyan (C). Further, the liquid discharge head unit (hereinafter referred to as "magenta liquid discharge head unit 210M1") installed next to the cyan liquid discharge head unit 210C1 is used for the magenta (M). Subsequently, the liquid discharge head unit (hereinafter referred to as "yellow liquid discharge head unit 210Y1") installed on the most downstream side is used for yellow (Y). Similarly, the device 10M2 that performs the image forming process also has a black liquid discharge head unit 210K2, a cyan liquid discharge head unit 210C2, a magenta liquid discharge head unit 210M2, and a yellow liquid discharge head unit 210Y2.

Each liquid ejection head unit ejects ink of each color to the web 120 based on image data or the like. The position where the liquid lands on the web 120 (hereinafter referred to as "discharge position") by the processing by the liquid discharge head unit is substantially directly below the liquid discharge head.

In the devices 10M1 and 10M2 that perform the image forming process, the black ink is ejected to the ejection position of the black liquid ejection head unit 210K1 (hereinafter referred to as “black ejection position PK”). Similarly, the cyan ink is ejected to the ejection position of the cyan liquid ejection head unit 210C1 (hereinafter referred to as “cyan ejection position PC”). Further, the magenta ink is ejected to the ejection position of the magenta liquid ejection head unit 210M1 (hereinafter referred to as “magenta ejection position PM”). Further, the yellow ink is ejected to the ejection position of the yellow liquid ejection head unit 210Y1 (hereinafter referred to as “yellow ejection position PY”). Since the same applies to the device 10M2 that performs image formation processing, the description thereof will be omitted. The controller 520 connected to each liquid ejection head unit controls, for example, the processing timing of each liquid ejection head unit ejecting ink and the actuator AC provided in each liquid ejection head unit. The control may not be performed by the controller 520, but may be performed by two or more controllers or circuits. The actuator will be described later.

Further, in the illustrated example, a plurality of rollers are installed for the liquid discharge head unit. As shown in the figure, a plurality of rollers are installed, for example, upstream and downstream with each liquid discharge head unit interposed therebetween.

Specifically, in the transport path of the web 120, a roller (hereinafter referred to as “first roller”) for supporting the web 120 is installed on the upstream side of each discharge position for each liquid discharge head unit. Further, a roller (hereinafter referred to as "second roller") for supporting the web 120 is installed on the downstream side from each discharge position. When the first roller and the second roller are installed in this way, so-called "fluttering" can be reduced at each discharge position. The first roller and the second roller are, for example, driven rollers. Further, the first roller and the second roller may be rollers rotated by a motor or the like.

The first roller, which is an example of the first support member, and the second roller, which is an example of the second support member, do not have to be rotating bodies such as driven rollers. That is, the first support member and the second support member may be members that support the object to be transported. For example, the first support member and the second support member may be a pipe or a shaft having a circular cross section. In addition, the first support member and the second support member may be a curved plate or the like whose portion in contact with the transported object has an arc shape. Hereinafter, an example will be described in which the first support member is the first roller and the second support member is the second roller.

Specifically, in any of the devices 10M1 and 10M2 that perform image forming processing, the first roller CR1K for black is installed on the upstream side of the web 120 at the black ejection position PK in the transport direction. On the other hand, the second roller CR2K for black is installed on the downstream side in the transport direction of the web 120 from the black discharge position PK.

Similarly, the first roller CR1C for cyan and the second roller CR2C for cyan are installed in the cyan liquid discharge head unit 210C. Further, a first roller CR1M for magenta and a second roller CR2M for magenta are installed on the magenta liquid discharge head unit 210M. Further, a first roller CR1Y for yellow and a second roller CR2Y for yellow are installed on the yellow liquid discharge head unit 210Y.

In FIG. 2, for example, one or more sensor devices for detecting the position of the web in the transport direction, the orthogonal direction, or both directions are installed in each liquid discharge head unit. The sensor device includes an optical sensor OS that uses light such as visible light and infrared light. The optical sensor OS may be, for example, a CCD (Charge Coupled Device) camera, a CMOS (Complementary Metal Oxide Sensor), or the like. That is, the sensor device is not limited to an optical sensor as long as it is a sensor that can detect information on the surface of the web, for example. Further, the sensor device is a sensor device capable of detecting the back surface or the front surface of the recording medium during image formation, as will be described later. Hereinafter, an example using an optical sensor will be described.

Further, the sensor device includes a laser light source as described later. When the laser beam emitted from the light source overlaps and interferes with the scattered waves scattered on the surface of the web 120, a speckle pattern or the like is generated. Then, the optical sensor OS possessed by each sensor device captures such a speckle pattern or the like and generates image data. The speckle pattern is an example of surface information on the web 120. In this way, based on the position change of the pattern imaged by the optical sensor OS, for example, the image forming apparatus obtains the movement amount for moving each liquid discharge head unit, the discharge timing of each liquid discharge head unit, and the like. Can be done.

Hereinafter, the “position where the sensor is installed” refers to a position where the sensor device detects the position and the like. Therefore, it is not necessary to install all the devices used for detection at the "position where the sensor is installed". That is, the hardware constituting the transported object detection device may be installed at a position where detection is performed. On the other hand, only the optical sensor OS may be installed at a position where detection is performed as a sensor, and other devices may be connected to the optical sensor OS with a cable and installed at another position. Further, in the following description, each sensor may be simply referred to as a “sensor” as a whole.

Further, it is desirable that the position where the sensor is arranged is close to the head unit. Then, it is assumed that the sensor is first installed for each head unit.

Specifically, in the example shown in FIG. 2, the black sensor device SENK1 of the device 10M1 that performs image formation processing is installed between the black first roller CR1K and the black second roller CR2K.

Similarly, the cyan sensor device SENC1 is installed between the cyan first roller CR1C and the cyan second roller CR2C.

Further, the magenta sensor device SENM1 is installed between the magenta first roller CR1M and the magenta second roller CR2M.

Furthermore, the yellow sensor device SENY1 is installed between the yellow first roller CR1Y and the yellow second roller CR2Y, as shown in the figure.

Further, it is more desirable that the position where the sensor is installed is a position closer to the first roller than the discharge position between the rollers. That is, it is more desirable that the position where the sensor is installed is upstream from each discharge position.

Specifically, it is desirable that the black sensor device SENK is installed upstream from the black discharge position PK to the position where the black first roller CR1K is installed.

Similarly, it is desirable that the cyan sensor device SENC be installed upstream from the cyan discharge position PC to the position where the cyan first roller CR1C is installed.

Further, it is desirable that the magenta sensor device SENM is installed upstream from the magenta discharge position PM to the position where the magenta first roller CR1M is installed.

Furthermore, it is desirable that the yellow sensor device SENY is installed upstream from the yellow discharge position PY to the position where the first yellow roller CR1Y is installed.

When the sensor device SEN is installed between the discharge position of each liquid and the roller on the upstream side, the transport device 100 can accurately detect the position of the web 120 and the like. When the sensor is installed at such a position, the sensor is installed upstream from each discharge position. Therefore, the transport device 100 first detects the position of the web 120 in the orthogonal direction, the transport direction, or both directions by using the sensor device SEN upstream. Therefore, the transport device 100 can calculate the processing timing at which each liquid discharge head unit discharges the liquid, the amount of movement of the head unit, or both. That is, since the web 120 is transported to the discharge position after the position of the web 120 is detected upstream, the transport device 100 calculates the processing timing or the head unit while the web 120 is transported to the discharge position. Can be moved, etc. Therefore, the transport device 100 can change the processing position with high accuracy.

On the other hand, if the position where the sensor is installed is directly under each liquid discharge head unit, the position where the processing is performed may shift due to a delay due to the control operation or the like. Therefore, if the position where the sensor is installed is upstream from each discharge position, the transport device 100 can reduce the deviation and perform the processing with high accuracy. Further, the vicinity of each discharge position may be restricted to the position where the sensor or the like is installed. However, if the delay of the control operation or the like is ignored, the position where the sensor is installed may be directly under each of the liquid discharge head units. When the sensor device SEN is directly underneath, there is also an advantage that the accurate movement amount underneath can be detected by the sensor. For example, if the control operation can be performed quickly, it is desirable that the sensor is located closer to the position directly under each liquid discharge head unit. In addition, if the error is acceptable, the position of the sensor is directly under each liquid discharge head unit or between each first roller and each second roller, and from directly under each liquid discharge head unit. It may be a downstream position or the like.

Further, the transport device may further arrange a sensor in addition to the illustrated black sensor SENK, cyan sensor SENC, magenta sensor SENM, and yellow sensor SENY. For example, the transport device may further arrange the sensor upstream of the black sensor SENK.

FIG. 3 is a top view showing a configuration example of an apparatus that performs image formation processing according to an embodiment of the present invention. Hereinafter, an example of arranging the sensor device in the device 10M1 that performs image formation processing will be shown. For example, each sensor device is located near the edge of the web 120 in the width direction as shown in the figure when viewed from a direction perpendicular to the recording surface of the web 120, and is arranged at a position overlapping the web 120. desirable. Each sensor device is arranged at the arrangement positions PS1, PS2, PS3, PS4 and the like. In this configuration, the controller 520 controls the actuators AC1, AC2, AC3, and AC4 to move each liquid discharge head unit in a direction orthogonal to the direction in which the web 120 is conveyed.

As shown in FIG. 2, in the device 10M1 that performs image formation processing, each sensor device is on the back side with respect to each liquid discharge head unit (opposite to the side on which each liquid discharge head unit is installed with respect to the web 120). Provided on the side).

The top view of the device 10M2 that performs the image forming process is almost the same. However, as shown in FIG. 2, in the present embodiment, each sensor device of the device 10M2 that performs image formation processing is on the same side with respect to each liquid discharge head unit (each liquid discharge head unit with respect to the web 120). Is installed on the same side as the side where is installed).

Further, actuator controllers CTL1, CTL2, CTL3 and CTL4 for controlling the actuators are connected to the actuators AC1, AC2, AC3 and AC4. Hereinafter, the actuators AC1, AC2, AC3 and AC4 may be collectively referred to simply as "actuator AC". Further, the actuator controllers CTL1, CTL2, CTL3 and CTL4 may be collectively referred to simply as "actuator controller CTL".

The actuator AC is, for example, a linear actuator or a motor. Further, the actuator AC may include a control circuit, a power supply circuit, a mechanical component, and the like.

The actuator controllers CTL1, CTL2, CTL3 and CTL4 are, for example, a driver circuit or the like.

FIG. 4 is a diagram showing an example of the outer shape of the liquid discharge head unit according to the embodiment of the present invention. FIG. 4A is a schematic plan view showing an example of each liquid discharge head unit.

As shown in the figure, the liquid discharge head unit is, for example, a line type head unit.

For example, in the black liquid discharge head unit 210K1, four heads 210K-1, 210K-2, 210K-3 and 210K-4 are arranged in a staggered manner in the orthogonal direction. For example, the head 210K-1 has a shape as shown in FIG. 4 (B). As a result, the black liquid ejection head unit 210K1 forms an image with black ink in the width direction (that is, in the orthogonal direction) of the region (so-called print region) in which the image is formed on the web 120. be able to. The configurations of the cyan liquid discharge head unit 210C1, the magenta liquid discharge head unit 210M1, and the yellow liquid discharge head unit 210Y1 are the same as those of the black liquid discharge head unit 210K, and the description thereof will be omitted. Further, since the liquid discharge head unit of the apparatus 10M2 that performs the image forming process has the same configuration, the description thereof will be omitted.

In the above description, an example in which the liquid discharge head unit is configured by four heads has been described, but the liquid discharge head unit may be configured by a single head.

<Example of an object to be detected device>
FIG. 5 is a block diagram showing a hardware configuration example for realizing the transported object detection device according to the embodiment of the present invention. For example, the transported object detection device is realized by hardware such as a sensor device SEN, a control circuit 52, a storage device 53, and a controller 520 as shown in the figure.

First, the sensor device SEN is, for example, the following device.

FIG. 6 is an external view showing an example of a device that realizes the sensor device according to the embodiment of the present invention. The illustrated sensor device SEN has a configuration in which a pattern or the like formed on the transported object is imaged when the transported object is irradiated with light from a light source. Specifically, the sensor device SEN first has an optical system such as a laser light source LD and a collimating optical system (CL) as an example of the light source. Further, the sensor device SEN has a CMOS image sensor as an optical sensor OS and a telecentric imaging optical system (TO) for condensing and forming an image on the CMOS image sensor in order to image a pattern.

For example, the optical sensor OS captures the pattern. Then, the controller 520 performs processing such as cross-correlation calculation based on the captured pattern and the pattern captured by the optical sensor OS included in the other sensor device SEN. Next, based on the movement of the correlation peak position calculated by the correlation calculation or the like, the controller 520 outputs the movement amount or the like that the transported object has moved from one optical sensor to the other optical sensor. In the illustrated example, the size of the sensor device SEN is 15 × 60 × 32 [mm] in width W × depth D × height H. The details of the correlation calculation will be described later.

The CMOS image sensor is an example of hardware that realizes an image pickup unit. In this example, the hardware that performs the correlation calculation is described as the controller 520, but the correlation calculation may be executed by the FPGA circuit mounted on any of the sensor devices.

The control circuit 52 controls the optical sensor OS and the like inside the sensor device. Specifically, the control circuit 52 outputs, for example, a trigger signal to the optical sensor OS to control the timing at which the optical sensor OS releases the shutter. Further, the control circuit 52 controls so that the two-dimensional image data can be acquired from the optical sensor OS. Then, the control circuit 52 sends the two-dimensional image data imaged and generated by the optical sensor OS to the storage device 53 or the like.

The storage device 53 is a so-called memory or the like. It is desirable that the storage device 53 has a configuration in which the two-dimensional image data sent from the control circuit 52 can be divided and stored in different storage areas.

The controller 520 is a microcomputer or the like. The controller 520 performs an operation using image data or the like stored in the storage device 53.

The control circuit 52 and the controller 520 are, for example, a CPU (Central Processing Unit), an electronic circuit, or the like. The control circuit 52 and the controller 520 do not have to be different devices. For example, the control circuit 52 and the controller 520 may be one CPU or the like. Further, the control circuit 52 and the controller 520 may be one FPGA circuit.

FIG. 7 is a functional block diagram showing an example of the functional configuration of the transported object detection device according to the embodiment of the present invention. As shown below, among the sensor device SENs installed for each liquid discharge head unit, the combination of the sensor device SENs installed for the black liquid discharge head unit 210K1 and the cyan liquid discharge head unit 210C1 is used. An example of a transported object detection device that detects the position of the web will be described. Further, as shown in the figure, the detection unit 52A, which is the detection function of the black sensor device SENK1 for the black liquid discharge head unit 210K1, outputs the image data related to the "A position", and the cyan for the cyan liquid discharge head unit 210C1. An example will be described in which the detection unit 52B, which is the detection function of the sensor device SENC1, outputs the image data related to the “B position”.

First, the detection unit 52A for the black liquid discharge head unit 210K1 is composed of, for example, an image pickup unit 16A, an image pickup control unit 14A, an image storage unit 15A, and the like. In this example, the detection unit 52B for the cyan liquid discharge head unit 210C1 has, for example, the same configuration as the detection unit 52A, and is composed of an image pickup unit 16B, an image pickup control unit 14B, an image storage unit 15B, and the like. Hereinafter, the detection unit 52A will be described as an example.

As shown in the figure, the image pickup unit 16A images the web 120 transported in the transport direction 10. The image pickup unit 16A is realized by, for example, an optical sensor OS or the like.

The image pickup control unit 14A includes a shutter control unit 141A and an image capture unit 142A. The image pickup control unit 14A is realized by, for example, a control circuit 52 or the like.

The image capture unit 142A acquires image data captured by the image pickup unit 16A.

The shutter control unit 141A controls the timing at which the image pickup unit 16A takes an image.

The image storage unit 15A stores the image data captured by the image pickup control unit 14A. The image storage unit 15A is realized by, for example, a storage device 53 or the like.

The calculation unit 53F can calculate the position of the pattern possessed by the web 120, the moving speed at which the web 120 moves, and the moving amount of the web 120 based on the respective image data stored in the image storage units 15A and 15B.

Further, the calculation unit 53F outputs data of a time difference Δt indicating the timing of releasing the shutter to the shutter control unit 141A. That is, the calculation unit 53F indicates to the shutter control unit 141A the timing to release the shutter so that the image data indicating the “A position” and the image data indicating the “B position” are imaged with a time difference Δt. May be good. The calculation unit 53F is realized by, for example, a controller 520 or the like.

The web 120 is a member having a scattering property on the surface or inside. Therefore, when the web 120 is irradiated with light such as laser light from the light source 51A and the light source 51B, the reflected light is diffusely reflected. Then, a pattern is formed on the web 120 by diffuse reflection. That is, the pattern is a spot called "speckle", a so-called speckle pattern or the like. Therefore, when the web 120 is imaged, image data showing the pattern is obtained as the surface information of the web 120.

As described above, since the position with the pattern can be known from the image data, the transport device can detect where the predetermined position of the web 120 is. The pattern is generated because the irradiated laser beam interferes with the uneven shape formed on the surface or the inside of the web 120.

Therefore, when the web 120 is conveyed, the pattern of the web 120 is also conveyed. Therefore, when the same pattern is detected at different times, the calculation unit 53F can calculate the movement amount of the web 120 based on the image data. That is, when the same pattern is detected upstream and downstream and the movement amount of the pattern moved is calculated, the calculation unit 53F can calculate the movement amount of the web 120. When the movement amount calculated in this way is converted per unit time, the calculation unit 53F can calculate the movement speed at which the web 120 moves.

As shown in the figure, the image pickup unit 16A and the image pickup unit 16B are installed at regular intervals in the transport direction 10. Then, the web 120 is imaged at each position via the image pickup unit 16A and the image pickup unit 16B.

Then, at intervals of the time difference Δt, the shutter control unit 141A causes the image pickup unit 16A and the image pickup unit 16B to take an image of the web 120. Specifically, assuming that the ideal transport speed is "V" and the relative distance, which is the interval at which the image pickup unit 16A and the image pickup unit 16B are installed in the transport direction 10, is "L", the time difference Δt is the following (1). It can be shown as an expression.

Δt = L / V (1)

In the above equation (1), since the relative distance L is the distance between the sensor device SENK1 and the sensor device SENC1, it can be specified by measuring the distance between the sensor device SENK1 and the sensor device SENK2 in advance.

Further, the transport device performs a cross-correlation calculation on the image data “D1 (n)” and “D2 (n)” indicating the respective images captured by the detection unit 52A and the detection unit 52B. Hereinafter, the image data generated by the cross-correlation operation is referred to as a “correlation image”. For example, the transport device calculates the deviation amount “ΔD (n)” based on the correlation image.

<Correlation operation example>
For example, the cross-correlation calculation is a calculation shown by the following equation (2).

D1 ★ D2 * = F-1 [F [D1] ・ F [D2] *] (2)

In the above equation (2), the image data "D1 (n)", that is, the image data indicating the image captured at the "A position" is referred to as "D1". Similarly, in the above equation (2), the image data “D2 (n)”, that is, the image data indicating the image captured at the “B position” is referred to as “D2”. Further, in the above equation (2), the Fourier transform is indicated by "F []" and the inverse Fourier transform is indicated by "F-1 []". Furthermore, in the above equation (2), the complex conjugate is indicated by "*" and the cross-correlation operation is indicated by "★".

As shown in the above equation (2), when the cross-correlation calculation "D1 ★ D2" is performed on the image data D1 and D2, the image data showing the correlated image is obtained. When the image data D1 and D2 are two-dimensional image data, the image data showing the correlated image is the two-dimensional image data. Further, when the image data D1 and D2 are one-dimensional image data, the image data showing the correlated image is one-dimensional image data.

In the correlated image, for example, when a broad luminance distribution becomes a problem, a phase-limited correlation method may be used. The phase-limited correlation method is, for example, a calculation shown by the following equation (3).

D1 ★ D2 * = F-1 [P [F [D1]] ・ P [F [D2] *]] (3)

In the above equation (3), "P []" indicates that only the phase is extracted in the complex amplitude. Further, all the amplitudes are set to "1".

In this way, the transport device can calculate the deviation amount ΔD (n) based on the correlation image even if the luminance distribution is broad.

The correlation image shows the correlation between the image data D1 and D2. Specifically, the higher the degree of coincidence between the image data D1 and D2, the steeper the peak, that is, the luminance that becomes the so-called correlation peak is output at the position closer to the center of the correlated image. Then, when the image data D1 and D2 match, the positions of the center and the peak of the correlated image overlap.

Based on the result of the correlation calculation, information such as the position difference, the movement amount, and the movement speed between the image data D1 captured with the time difference Δt and the image data D2 is output. For example, in the orthogonal direction, it is possible to detect how much the web 120 has moved in the orthogonal direction between the image data D1 and the image data D2. It may be detected as the movement speed instead of the movement amount. The calculation unit 53F can calculate the movement amount of the cyan liquid discharge head unit 210C1 from the calculation result of the correlation calculation.

Based on the calculation result of the calculation unit 53F, the moving unit 57F controls the actuator AC2 of FIG. 3 to control the landing position of the liquid. The moving unit 57F is configured by, for example, an actuator controller CTL. The function of the moving unit 57F may be configured not only by the actuator controller CTL but also by the controller 520. Further, it may be configured by the controller 520.

Further, the calculation unit 53F can also determine how much the movement amount of the web in the transport direction deviates from the relative distance L based on the result of the correlation calculation. That is, from the two-dimensional image data captured by the image pickup units 16A and 16B sensors, the calculation unit 53F may also be used for detecting that the positions in the transport direction and the orthogonal direction may be calculated. When used in this way, the cost can be reduced in each direction. In addition, since the number of sensors can be reduced, space can be saved.

The calculation unit 53F calculates the discharge timing of the cyan liquid discharge head unit 210C based on the calculation of how much the transport amount of the web 120 deviates from the ideal distance. Based on this calculation result, the control unit 54F controls the discharge by the cyan liquid discharge head unit 210C1. The timing of discharging the liquid is controlled by the second signal SIG2 or the like for the cyan liquid discharge head unit 210C output by the control unit 54F. When the discharge timing of the black liquid discharge head unit 210K is calculated, the discharge timing of the black liquid discharge head unit 210K is controlled by the first signal SIG1 for the black liquid discharge head unit 210K. The control unit 54F is realized by, for example, a controller 520 or the like.

The correlation calculation may be calculated as follows, for example.

FIG. 8 is a block diagram showing an example of a correlation calculation method according to an embodiment of the present invention. For example, when the transport device performs the correlation calculation according to the configuration as shown in the figure, the relative position in the orthogonal direction of the web 120 at the position where two or more image data are captured, the movement amount, the movement speed, or a combination thereof or 2 It is possible to calculate the amount of deviation from the ideal transport position of the web 120, the moving speed, and the like at the timing when the two image data are captured.

Specifically, as shown in the figure, the transport device includes a first two-dimensional Fourier transform unit FT1, a second two-dimensional Fourier transform unit FT2, a correlation image data generation unit DMK, a peak position search unit SR, and a calculation unit CAL. And a configuration having a conversion result storage unit MEM.

The first two-dimensional Fourier transform unit FT1 converts the first image data D1. Specifically, the first two-dimensional Fourier transform unit FT1 has a configuration including a Fourier transform unit FT1a for the orthogonal direction and a Fourier transform unit FT1b for the transport direction.

The Fourier transform unit FT1a for the orthogonal direction performs a one-dimensional Fourier transform on the first image data D1 in the orthogonal direction. Then, the Fourier transform unit FT1b for the transport direction performs one-dimensional Fourier transform of the first image data D1 in the transport direction based on the conversion result by the Fourier transform unit FT1a for the orthogonal direction. In this way, the Fourier transform unit FT1a for the orthogonal direction and the Fourier transform unit FT1b for the transport direction perform one-dimensional Fourier transform in the orthogonal direction and the transport direction, respectively. The first two-dimensional Fourier transform unit FT1 outputs the conversion result converted in this way to the correlation image data generation unit DMK.

Similarly, the second two-dimensional Fourier transform unit FT2 transforms the second image data D2. Specifically, the second two-dimensional Fourier transform unit FT2 has a configuration including a Fourier transform unit FT2a for the orthogonal direction, a Fourier transform unit FT2b for the transport direction, and a complex conjugate unit FT2c.

The Fourier transform unit FT2a for the orthogonal direction performs a one-dimensional Fourier transform on the second image data D2 in the orthogonal direction. Then, the Fourier transform unit FT2b for the transport direction performs one-dimensional Fourier transform of the second image data D2 in the transport direction based on the conversion result by the Fourier transform unit FT2a for the orthogonal direction. In this way, the Fourier transform unit FT2a for the orthogonal direction and the Fourier transform unit FT2b for the transport direction perform one-dimensional Fourier transform in the orthogonal direction and the transport direction, respectively.

Next, the complex conjugate unit FT2c calculates the complex conjugate of the conversion result by the Fourier transform unit FT2a for the orthogonal direction and the Fourier transform unit FT2b for the transport direction. Then, the second two-dimensional Fourier transform unit FT2 outputs the complex conjugate calculated by the complex conjugate unit FT2c to the correlation image data generation unit DMK.

Subsequently, the correlated image data generation unit DMK has the conversion result of the first image data D1 output from the first two-dimensional Fourier transform unit FT1 and the second image output from the second two-dimensional Fourier transform unit FT2. Correlated image data is generated based on the conversion result of the data D2.

The correlation image data generation unit DMK has a configuration including an integration unit DMKa and a two-dimensional inverse Fourier transform unit DMKb.

The integration unit DMKa integrates the conversion result of the first image data D1 and the conversion result of the second image data D2. Then, the integration unit DMKa outputs the integration result to the two-dimensional inverse Fourier transform unit DMKb.

The two-dimensional inverse Fourier transform unit DMKb performs a two-dimensional inverse Fourier transform on the integration result by the integration unit DMKa. When the two-dimensional inverse Fourier transform is performed in this way, the correlated image data is generated. Then, the two-dimensional inverse Fourier transform unit DMKb outputs the correlated image data to the peak position search unit SR.

The peak position search unit SR searches for a peak position having a peak luminance (peak value) that has the steepest (that is, a steep rise) in the generated correlated image data. First, a value indicating the intensity of light, that is, the magnitude of brightness is input to the correlated image data. The brightness is input in a matrix.

In the correlated image data, the luminance is arranged at the pixel pitch interval of the area sensor, that is, the pixel size interval. Therefore, it is desirable that the search for the peak position is performed after performing so-called subpixel processing. In this way, when the sub-pixel processing is performed, the peak position can be searched with high accuracy. Therefore, the transport device can accurately output the position, the moving amount, the moving speed, and the like.

For example, the search by the peak position search unit SR is performed as follows.

FIG. 9 is a diagram showing an example of a method for searching for a peak position in a correlation calculation according to an embodiment of the present invention. In the figure, the horizontal axis indicates the position in the transport direction in the image indicated by the correlated image data. On the other hand, the vertical axis indicates the brightness for each pixel indicated by the correlated image data.

Hereinafter, among the brightnesses indicated by the correlated image data, three data of the first data value q1, the second data value q2, and the third data value q3 will be described as an example. That is, in this example, the peak position search unit SR searches for the peak position P on the curve k connecting the first data value q1, the second data value q2, and the third data value q3.

First, the peak position search unit SR calculates each difference in the brightness of the pixels indicated by the correlated image data. Then, the peak position search unit SR extracts a combination of data values having the largest difference value among the calculated differences. Next, the peak position search unit SR extracts a combination adjacent to the combination of data values having the largest difference value. In this way, the peak position search unit SR can extract three data as shown in the illustrated first data value q1, second data value q2, and third data value q3. Then, when the curve k is calculated by connecting the three extracted data, the peak position search unit SR can search for the peak position P. By doing so, the peak position search unit SR can search for the peak position P at a higher speed by reducing the amount of calculation such as sub-pixel processing. The position of the combination of data values having the largest difference value is the steepest position. Further, the sub-pixel processing may be processing other than the above processing.

As described above, when the peak position search unit SR searches for the peak position, for example, the following calculation result can be obtained.

FIG. 10 is a diagram showing an example of a calculation result of a correlation calculation according to an embodiment of the present invention. The figure shows the correlation intensity distribution of the cross-correlation function. In the figure, the X-axis and the Y-axis indicate the serial numbers of the pixels. A peak position such as the illustrated "correlation peak" is searched by the peak position search unit SR.

The calculation unit CAL calculates the relative position, movement amount, movement speed, etc. of the web. For example, the calculation unit CAL can calculate the relative position and the amount of movement by calculating the difference between the center position of the correlated image data and the peak position searched by the peak position search unit SR.

Further, the calculation unit CAL can calculate the movement speed by dividing the movement amount by time, for example.

As described above, the transport device can detect the relative position, the movement amount, the movement speed, and the like by the correlation calculation. The detection method of relative position, movement amount, movement speed, etc. is not limited to this. For example, the transport device may detect a relative position, a movement amount, a movement speed, or the like as follows.

First, the transport device binarizes the brightness of each of the first image data and the second image data. That is, the transport device is set to "0" if the brightness is equal to or less than a preset threshold value, and is set to "1" if the brightness is larger than the threshold value. The transport device may detect the relative position by comparing the first image data and the second image data binarized in this way.

In the figure, an example in which there is a fluctuation in the Y direction has been described, but when there is a fluctuation in the X direction, the peak position is generated at a position shifted in the X direction as well.

Further, the transport device may detect a relative position, a movement amount, a movement speed, or the like by another detection method. For example, the transport device may detect a relative position from each pattern reflected in each image data by so-called pattern matching processing or the like.

By performing the correlation calculation as described above, the transport device can grasp the amount of deviation indicating how much the object to be transported deviates from a predetermined position in the transport direction, the orthogonal direction, or both directions.

<Example of control unit>
The controller 520, which is an example of the control unit, has, for example, the configuration described below.

FIG. 11 is a block diagram showing an example of the hardware configuration of the control unit according to the embodiment of the present invention. For example, the controller 520 has a host device 71 such as an information processing device and a main body side control device 72. In the illustrated example, the controller 520 controls the transported object to form an image under the control of the main body side control device 72 based on the image data and the control data input from the host device 71.

The host device 71 is, for example, a PC (Personal Computer) or the like. Further, the main body side control device 72 has a printer controller 72C and a printer engine 72E.

The printer controller 72C controls the operation of the printer engine 72E. First, the printer controller 72C transmits / receives control data to / from the host device 71 via the control line 70LC. Further, the printer controller 72C transmits / receives control data to / from the printer engine 72E via the control line 72LC. Then, when the control data is received, the print conditions and the like indicated by the control data are input to the printer controller 72C, and the printer controller 72C stores the print conditions and the like by the registers and the like. Next, the printer controller 72C controls the printer engine 72E based on the control data, and performs image formation according to the print job data, that is, the control data.

The printer controller 72C has a CPU 72Cp, a print control device 72Cc, and a storage device 72Cm. The CPU 72Cp and the print control device 72Cc are connected by a bus 72Cb and communicate with each other. Further, the bus 72Cb is connected to the control line 70LC via a communication I / F (interface) or the like.

The CPU 72Cp controls the operation of the entire main body side control device 72 by a control program or the like. That is, the CPU 72Cp is an arithmetic unit and a control unit.

The print control device 72Cc transmits / receives data indicating a command, status, or the like to / from the printer engine 72E based on the control data transmitted from the host device 71. As a result, the print control device 72Cc controls the printer engine 72E.

Data lines 70LD-C, 70LD-M, 70LD-Y and 70LD-K, that is, a plurality of data lines are connected to the printer engine 72E. Then, the printer engine 72E receives the image data from the host device 71 via the plurality of data lines. Next, the printer engine 72E forms an image of each color based on the control by the printer controller 72C.

The printer engine 72E has data management devices 72EC, 72EM, 72EY and 72EK, that is, a plurality of data management devices. Further, the printer engine 72E has an image output device 72Ei and a transfer control device 72Ec.

FIG. 12 is a block diagram showing an example of the hardware configuration of the data management device included in the control unit according to the embodiment of the present invention. For example, a plurality of data management devices have the same configuration. Hereinafter, an example in which each data management device has the same configuration will be described, and the data management device 72EC will be described as an example. Therefore, duplicate description will be omitted.

The data management device 72EC has a logic circuit 72ECl and a storage device 72ECm. As shown in the figure, the logic circuit 72ECl is connected to the host device 71 via the data line 70LD-C. Further, the logic circuit 72ECl is connected to the print control device 72Cc via the control line 72LC. The logic circuit 72ECl is realized by an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or the like.

The logic circuit 72ECl stores the image data input from the host device 71 in the storage device 72ECm based on the control signal input from the printer controller 72C.

Further, the logic circuit 72ECl reads out the image data Ic for cyan from the storage device 72ECm based on the control signal input from the printer controller 72C. Next, the logic circuit 72ECl sends the read image data Ic for cyan to the image output device 72Ei.

It is desirable that the storage device 72ECm has a capacity of storing about 3 pages of image data. When the image data of about 3 pages can be stored, the storage device 72ECm can store the image data input from the host device 71, the image data during image formation, and the image data for next image formation.

FIG. 13 is a block diagram showing an example of the hardware configuration of the image output device included in the control unit according to the embodiment of the present invention. As shown in the figure, the image output device 72Ei includes an output control device 72Eic, a black liquid discharge head unit 210K, a cyan liquid discharge head unit 210C, a magenta liquid discharge head unit 210M, and a yellow liquid discharge head, which are liquid discharge head units of each color. It has a unit 210Y.

The output control device 72Eic outputs image data of each color to the liquid discharge head unit of each color. That is, the output control device 72Eic controls the liquid discharge head unit of each color based on the input image data.

The output control device 72Eic controls a plurality of liquid discharge head units simultaneously or individually. That is, the output control device 72Eic receives the input of the timing and controls to change the timing of discharging the liquid to each liquid discharge head unit. The output control device 72Eic may control any of the liquid discharge head units based on the control signal input from the printer controller 72C. Further, the output control device 72Eic may control any of the liquid discharge head units based on an operation by the user or the like.

The main body side control device 72 has different routes for inputting image data from the host device 71 and a route used for transmission / reception between the host device 71 and the main body side control device 72 based on the control data. This is an example.

The transport control device 72Ec is a driver device or the like. For example, the transport control device 72Ec controls a motor or the like connected to each roller or the like to transport the web 120.

<Example of detection of position, etc.>
FIG. 14 is a timing chart showing an example of detecting the position of the object to be transported by the transport device according to the embodiment of the present invention.

The transport device calculates the amount of fluctuation in the position of the object to be transported based on a plurality of sensor data. Specifically, the transport device outputs a calculation result indicating the amount of fluctuation based on the first sensor data S1 and the second sensor data S2. In the detection shown in the figure, the sensor data output by the sensor device installed upstream is the first sensor data S1. On the other hand, the sensor data output by the sensor device installed downstream becomes the second sensor data S2.

The fluctuation amount is calculated for each liquid discharge head unit, for example. Hereinafter, an example of calculating the fluctuation amount for the cyan liquid discharge head unit 210C will be described. In this example, the black sensor device SENK1 outputs the first sensor data S1, while the cyan sensor device SENC1 outputs the second sensor data S2.

Hereinafter, it is assumed that the distance between the black sensor device SENK1 and the cyan sensor device SENC1, that is, the distance between the sensors is “L2”. Further, it is assumed that the moving speed detected based on the sensor data is "V". Further, it is assumed that the moving time elapsed for the conveyed object to be conveyed from the upstream black sensor device SENK1 to the downstream cyan sensor device SENC1 is "T2". In this case, the travel time is calculated as "T2 = L2 / V".

Further, the sampling interval by the optical sensor is set to "A". Further, the number of samplings between the sensors is set to "n". In this case, the number of samplings is calculated as "n = T2 / A".

The illustrated calculation result, that is, the fluctuation amount is defined as “ΔX”. For example, as shown in the figure, when the detection cycle is "0", the fluctuation amount includes the first sensor data S1 before the travel time "T2" and the second sensor data S2 having the detection cycle "0". Calculated by comparison. Specifically, the fluctuation amount is calculated as "ΔX = X2 (0) −X1 (n)".

Next, it is desirable that the transfer device controls the actuator AC2 so as to compensate for the fluctuation amount “ΔX” and moves the cyan liquid discharge head unit 210C1 in the orthogonal direction. In this way, even if the position of the transported object fluctuates in the orthogonal direction, the transport device can accurately process the transported object. Further, when the fluctuation amount is calculated based on the image data captured by the sensor data between the two points with the most upstream sensor device, the fluctuation amount can be calculated without integrating the position information of each sensor device. Therefore, in this way, the accumulation of detection errors by each sensor device can be reduced.

Further, the first sensor data S1 is not limited to the image data detected by the sensor installed on the upstream side of the liquid discharge head unit to be moved. That is, the image data from the sensor device installed on the upstream side of the liquid discharge head unit to be moved may be used.

The second sensor data S2 is preferably image data captured by a sensor device installed at a position closest to the liquid discharge head unit to be moved.

Further, the fluctuation amount and the like may be calculated from three or more image data.

In this way, the transport device controls the movement of the liquid discharge head unit based on the fluctuation amount calculated from the plurality of sensor data, and performs processing on the web 120.

<Processing timing control example>
FIG. 15 is a timing chart showing an example of controlling the processing timing by the transport device according to the embodiment of the present invention. In the illustrated example, the first timing T1 is the detection timing for the black sensor device SENK1 to perform detection. Further, the second timing T2 is detected by the processing timing at which the black liquid is discharged, and the third timing T3 is detected by the cyan sensor device SENC1 installed between the black liquid discharge head unit 210K1 and the cyan liquid discharge head unit 210C1. It is the detection timing to perform. Further, the fourth timing T4 is the timing at which the cyan liquid is scheduled to be discharged, and the fifth timing T5 is the cyan liquid discharge process after being corrected based on the image data captured by the sensor device SENK1 and the sensor device SENC1. Is the processing timing at which is performed.

In this example, the position where the cyan sensor device SENC performs detection is hereinafter simply referred to as "detection position". As shown in the figure, the detection position is assumed to be a position "installation distance D" from the landing position of the cyan liquid discharge head unit 210C. Further, in the following example, it is assumed that the interval at which each sensor is installed is the same as the installation interval (relative distance L) of each liquid discharge head unit. Further, it is assumed that the web 120 is moving at an ideal moving speed V. The ideal moving speed V is stored by the printer controller 72C.

First, at the first timing T1, which is the timing "D ÷ V" earlier than the timing at which the black liquid discharge head unit 210K1 discharges the liquid, the black sensor device SENK1 acquires image data. In the illustrated example, the image acquired at the first timing T1 is indicated by the first image signal PA. The image data corresponds to the image data D1 (n) at the "position A" shown in FIG. 7. Next, the transfer device turns the first signal SIG1 “ON” so that the black liquid discharge head unit 210K is discharged with the liquid at the second timing T2.

Next, at the third timing T3, the transfer device acquires image data. In the illustrated example, the image acquired at the third timing T3 is represented by the second image signal PB, and the image data corresponds to the image data D2 (n) at the “B position” shown in FIG. 7. Next, the transport device performs a cross-correlation operation on the image data D1 (n) and D2 (n). In this way, the transport device can calculate the deviation amount ΔD (0). Then, based on the deviation amount ΔD (0), the ON timing of the second signal SIG2, which is the discharge timing of the cyan liquid discharge head unit 210C1, is controlled.

In a state where the roller has no thermal expansion and there is no slip between the roller and the web 120, that is, in a so-called ideal state, the transport device moves a predetermined position of the web 120 at a relative distance L. It takes time of "L ÷ V" to transport by V.

Therefore, the "imaging cycle T" is set, for example, "imaging cycle T = imaging time difference = relative distance L / moving speed V". In the illustrated example, the optical sensor OSs of the black sensor device SENK1 and the cyan sensor device SENC1 are installed at intervals of a relative distance L. If it is in an ideal state, the predetermined portion of the web 120 detected by the black sensor device SENK1 is conveyed to the detection position of the cyan sensor device SENC1 after "L ÷ V" time.

On the other hand, in reality, there are many cases where thermal expansion occurs in the rollers or slippage occurs between the rollers and the web 120, so that the rollers are not conveyed at the ideal transfer amount. In the correlation calculation method shown in FIG. 8, when “imaging cycle T = relative distance L / moving speed V” is set, the timing at which the image data D1 (n) is imaged by the black sensor device SENK1 and the cyan sensor. The time difference from the timing at which the image data D2 (n) is captured by the device SENC1 is “L ÷ V”. In this way, the transport device may calculate the deviation amount ΔD (0) with “L ÷ V” as the “imaging period T”. Hereinafter, an example of the third timing illustrated will be described.

At the third timing T3, the transport device calculates the deviation amount ΔD (0), which is an example of the second distance. Then, the transport device changes the processing timing at which the cyan liquid discharge head unit 210C1 discharges the liquid, that is, the ON timing of the second signal SIG2, based on the installation distance D, the deviation amount ΔD (0), and the moving speed V. ..

The transfer device determines the fourth timing T4 based on an ideal state such as no thermal expansion in the rollers, that is, “L ÷ V”. On the other hand, in reality, the position where the liquid is to be discharged is a position of a deviation amount ΔD (0) from the position where the cyan liquid discharge head unit 210C discharges the liquid due to thermal expansion of the roller or the like. Therefore, it takes time of "ΔD (0) ÷ V" for the web to be transported from the detection position of the cyan sensor device SENC1 to the position where the actual cyan liquid discharge head unit 210C discharges the liquid. Therefore, the transport device changes the processing timing to the fifth timing T5 so that the liquid can be discharged at a position where the deviation amount ΔD (0) with respect to the ideal position.

Specifically, the amount of change in the processing timing is "(ΔD (0) −D) / V" in consideration of the deviation amount ΔD (0). In this way, the transport device changes the timing at which the second signal SIG2 is turned “ON” from the fourth timing T4 by “(ΔD (0) −D) / V”. In this way, even if the rollers are thermally expanded, the processing timing of the transport device is changed based on the displacement amount ΔD (0), the installation distance D, and the moving speed V, so that the liquid can be transferred in the transport direction. The accuracy of the landing position can be improved.

In addition, the moving speed in each ideal state may be preset in the transport device for each mode.

Although the example of changing and determining the processing timing has been described above, the transport device directly calculates the processing timing for discharging the liquid to the liquid discharge head unit based on the displacement amount, “V” and “D”. You may decide.

<Example of double-sided processing>
FIG. 16 is a flowchart showing a processing example by the transport device according to the embodiment of the present invention. The process shown in the figure is an example of processing by the transfer device having the configuration shown in FIG. Hereinafter, the steps from the detection by the yellow sensor device SENY1 in FIG. 2 to the process of forming an image by the yellow liquid discharge head unit 210Y1 and the black liquid discharge head unit 210K2 will be described for convenience. From pattern detection by the black sensor device SENK1 to image formation processing by the magenta liquid discharge head unit 210M1, in pattern detection and so-called double-sided printing, an image is displayed on one side (hereinafter referred to as "first side FE1"). However, the description thereof will be omitted.

In step SP01, the yellow sensor device SENY1 detects a pattern on the object to be transported. That is, the yellow sensor device SENY1 captures image data for calculating a position or the like on a surface different from the first surface FE1 of the object to be transported (hereinafter referred to as "second surface FE2"). Perform the detection procedure.

In step SP02, the controller 520 previously captures and stores the image data captured by the magenta sensor device SENM1 at almost the same position on the second surface FE2, and the image data captured by the yellow sensor device SENY1. Based on this, the first correlation calculation and the like are performed. Specifically, in step SP02, the processing as shown in FIG. 8 is performed. As a result of the correlation calculation, any one of the relative position, the amount of movement, the movement speed, or a combination thereof in the orthogonal direction of the web 120 between the magenta sensor device SENM1 and the yellow sensor device SENY1 may be calculated. Further, any one of the displacement amount, the transport speed, or a combination thereof from the ideal transport position from the magenta sensor device SEM1 to the yellow sensor device SENY1 in the transport direction of the web 120 may be calculated.

In step SP03, the controller 520 controls the actuator AC4 of the yellow liquid discharge head unit 210Y1 based on the result of the first correlation calculation and the like, and processes the first surface FE1 of the yellow liquid discharge head unit 210Y1 in the orthogonal direction. Move to.

In step SP04, the controller 520 controls the discharge timing of the yellow liquid discharge head unit 210Y1 based on the result of the correlation calculation and the like in step SP02, and causes the yellow liquid discharge head unit 210Y1 to discharge. In step SP04, the process as shown in FIG. 15 is performed.

That is, step SP04 is a process of forming an image on the first surface FE1 in double-sided printing.

Between step SP04 and step SP05, the goods to be transported are inverted by the turnstile 130.

In step SP05, the black sensor device SENK2 captures a portion imaged by the yellow sensor device SENY1. That is, in the process for the first surface FE1, the transport device performs the second detection procedure of capturing an image of substantially the same location as that used for calculating the position and the like. That is, also in the second detection procedure, the transport device takes an image of the second surface FE2. Specifically, in the detection using image data as shown in FIG. 7, the transport device includes the same pattern as the pattern captured when used for the processing on the first surface FE1 in the image data. , The pattern is imaged.

In step SP06, the controller 520 performs a second correlation calculation or the like based on the image data captured by the yellow sensor device SENY1 and the image data captured by the black sensor device SENK2. As a result of the correlation calculation, any one of the orthogonal relative position, the amount of movement, the movement speed, or a combination thereof of the web 120 between the yellow sensor device SENY1 and the black sensor device SENK2 may be calculated. Further, in the transport direction of the web 120, either the amount of displacement from the ideal transport position between the yellow sensor device SENY1 and the black sensor device SENK2, the transport speed, or a combination thereof may be calculated.

In step SP07, the controller 520 controls the actuator AC1 of the black liquid discharge head unit 210K2 based on the result of the correlation calculation of step SP06, and causes the black liquid discharge head unit 210K2 that performs processing on the second surface FE2 in the orthogonal direction. Move it.

In step SP08, the controller 520 controls the discharge timing of the black liquid discharge head unit 210K2 based on the result of the correlation calculation and the like in step SP06, and causes the black liquid discharge head unit 210K2 to discharge.

That is, step SP08 is a process of forming an image on the second side FE2 in so-called double-sided printing.

From the detection of the pattern by the cyan sensor device SENC2 to the image formation process by the yellow liquid discharge head unit 210Y2, the pattern detection and the image formation process on the second surface FE2 are performed, but the description thereof will be omitted.

As described above, when the portion imaged by the first detection procedure of the device 10M1 that performs the image formation process is detected before the image formation process of the device 10M2 that performs the image formation process, the transport device 100 is positioned in double-sided printing. Matching is possible. For example, the transport device 100 can form images at the same location on both sides in the transport direction.

Here, the correlation calculation and the like were performed based on the image data captured by the yellow sensor device SENY1 and the black sensor device SENK2, but the image captured by the black sensor device SENK1 instead of the yellow sensor device SENY1. Data and correlation calculation may be performed. In this case, the above-mentioned effect that the installation position deviation for each sensor device SEN is not integrated is obtained.

<Function configuration example>
FIG. 17 is a functional block diagram showing a functional configuration example of the transport device according to the embodiment of the present invention. As shown in the figure, the transport device 100 has a functional configuration including a first detection unit 52D and a second detection unit 52E. The configuration of the detection unit and the hardware configuration for realizing the detection unit are the same as those of the detection units 52A and 52B in FIG. 7. Further, in the figure, among the black liquid discharge head unit 210K1, the cyan liquid discharge head unit 210C1, the magenta liquid discharge head unit 210M1 and the yellow liquid discharge head unit 210Y1 which are examples of the first processing unit, the yellow liquid discharge head unit 210Y1 is shown. Illustrated. Further, among the black liquid discharge head unit 210K2, the cyan liquid discharge head unit 210C2, the magenta liquid discharge head unit 210M2, and the yellow liquid discharge head unit 210Y2, which are examples of the second processing unit, the black liquid discharge head unit 210K2 is shown.

Further, as shown in the figure, it is desirable that the transport device 100 has an inversion unit 100F2, a moving unit 57F, a calculation unit 53F, and a control unit 54F. Hereinafter, the illustrated functional configuration will be described as an example.

The yellow liquid discharge head unit 210Y1 performs a first process such as image formation on the first surface FE1.

The black liquid discharge head unit 210K2 performs a second process such as image formation on the second surface FE2.

The first detection unit 52D detects a position used for calculating the position, the moving speed, the moving amount, or a combination thereof of the web. In this example, the first detection unit 52D detects the surface information of the second surface FE2 by performing an image pickup. For example, the first detection unit 52D is realized by a black sensor device SENK1, a cyan sensor device SENC1, a magenta sensor device SENM1, a yellow sensor device SENY1, and the like.

The second detection unit 52E detects a portion detected by the first detection unit 52D before the second processing is performed. For example, the second detection unit 52E is realized by a black sensor device SENK2 or the like. The second detection unit 52E also detects the second surface FE2.

The inversion unit 100F2 inverts the first surface FE1 and the second surface FE2 so that the surface to be processed differs between the first process and the second process. For example, the reversing portion 100F2 is realized by a turn bar 130 or the like.

The moving unit 57F moves the head unit based on the calculation result of the calculation unit 53F. The hardware that realizes the moving unit 57F is the same as that of the moving unit in FIG. 7.

<Second Embodiment>
In the second embodiment, the arrangement of the sensor device is different from that in the first embodiment. Hereinafter, the differences will be mainly described, and duplicate explanations will be omitted.

FIG. 18 is a schematic view showing an example of arrangement of sensors in the transport device according to the second embodiment of the present invention. Compared with FIG. 2, first, in the illustrated example, the black sensor device SENK2, the cyan sensor device SENC2, the magenta sensor device SENM2, and the yellow sensor device SENY2 detect the first surface FE1. Further, in the illustrated example, the point that the sensor device SEN2 is added is different.

In the second embodiment, it is desirable that the sensor device SEN2 detects a portion substantially the same as the portion detected by the yellow sensor device SENY1. Specifically, the sensor device SEN2 captures a portion where the pattern captured by the yellow sensor device SENY1 is included in the image data captured by the sensor device SEN2. In this way, the transport device can calculate the amount of deviation from the detection by the yellow sensor device SENY1 and the like. Further, the black sensor device SENK2, the cyan sensor device SENC2, the magenta sensor device SENM2, and the yellow sensor device SENY2 are located on opposite sides of the liquid discharge head unit 210 for processing the second surface via the web 120. By locating the sensor device SENK2 for black, the sensor device SENC2 for cyan, the sensor device SENM2 for magenta, and the sensor device SENY2 for yellow can be prevented from being contaminated with liquid mist or the like.

The flow of the second embodiment is different from the flow of the first embodiment in that the sensor device for performing the second detection in step SP05 is the sensor device SEN2, but the flow itself is the same.

<Function configuration example>
FIG. 19 is a functional block diagram showing a functional configuration example of a transport device according to an embodiment of the second embodiment of the present invention. As compared with FIG. 17, in the transport device 100, the second detection unit 52E and the third detection unit 52F are different. Hereinafter, the same parts as those in FIG. 17 will be omitted.

In the illustrated functional configuration, the second detection unit 52E detects the same second surface FE2 as the second surface FE2 processed by the black liquid discharge head unit 210K2, which is an example of the second processing unit. The second surface FE2 is the same surface as the surface detected by the first detection unit 52D for processing the processing surface of the first processing unit. For example, the second detection unit 52E is realized by the sensor device SEN2 or the like.

The third detection unit 52F detects the first surface FE1 different from the second surface FE2 processed by the black liquid discharge head unit 210K2. For example, the third detection unit 52F is realized by a black sensor device SENK2, a cyan sensor device SENC2, a magenta sensor device SENM2, a yellow sensor device SENY2, and the like. The third detection unit 52F is used to align the processes with respect to the second surface.

In this example, the transport device 100 performs alignment and the like in double-sided printing based on the location detected by the first detection unit 52D and the location detected by the second detection unit 52E.

<Third Embodiment>
In the third embodiment, the arrangement of the sensor device is different from that in the second embodiment. Hereinafter, the differences will be mainly described, and duplicate explanations will be omitted.

FIG. 20 is a schematic view showing an example of arrangement of sensors in the transport device according to the third embodiment of the present invention. As compared with FIG. 18, as shown in the figure, the third embodiment is different in that the sensor device SEN3 is added.

In the third embodiment, the sensor device SEN3 is an arrangement of sensors installed upstream of the black sensor device SENK2, the cyan sensor device SENC2, the magenta sensor device SENM2, and the yellow sensor device SENY2. It is desirable that the sensor device SEN2 and the sensor device SEN3 have the same position in the transport direction, but either of them may be upstream as long as the positional relationship with each other is known. Hereinafter, as shown in the figure, an example in which the sensor device SEN2 and the sensor device SEN3 are at the same position in the transport direction will be described.

In the third embodiment, it is desirable that the sensor device SEN2 detects a portion substantially the same as the portion detected by the yellow sensor device SENY1. Specifically, the sensor device SEN2 captures a portion where the pattern captured by the yellow sensor device SENY1 is included in the image data captured by the sensor device SEN2. Further, the black sensor device SENK2 detects a portion substantially the same as the portion detected by the sensor device SEN3. In this way, the transport device can calculate the amount of deviation from the detection by the yellow sensor device SENY1 and the like. Further, it is possible to prevent the black sensor device SENK2, the cyan sensor device SENC2, the magenta sensor device SENM2, and the yellow sensor device SENY2 from being contaminated with liquid mist or the like. Further, the accuracy of the processing position on the second surface can be improved as compared with the configuration shown in FIG.

<Example of double-sided processing>
FIG. 21 is a flowchart showing a processing example by the transfer device according to the third embodiment of the present invention. As compared with FIG. 16, in the third embodiment, after the first processing for the first surface, step SP09 for performing the first detection for the first surface and the second detection for the first surface are performed. The difference is that step SP10, step SP11 for performing the third correlation calculation, and step SP12 for performing the addition calculation in response to the processing of step SP06 and step SP11 are added. Hereinafter, the differences will be mainly described, and the overlapping points will be omitted.

In step SP05 shown in FIG. 21, the sensor device SEN2 detects a portion substantially the same as the portion detected by the yellow sensor device SENY1. That is, in the second detection procedure, the image data which is the surface information is detected by imaging the second surface FE2.

In step SP06, the controller 520 performs a second correlation calculation or the like based on the image data captured by the yellow sensor device SENY1 and the image data captured by the sensor device SEN2. As a result of the correlation calculation, any one of the relative position, the amount of movement, the movement speed, or a combination thereof in the orthogonal direction of the web 120 between the yellow sensor device SENY1 and the sensor device SEN2 may be calculated. Further, any one of the amount of positional deviation from the ideal transport position from the yellow sensor device SENY1 to the sensor device SEN2 in the transport direction of the web 120, the transport speed, or a combination thereof may be calculated. Here, as an example, it is assumed that the amount of movement in the orthogonal direction and the amount of misalignment in the transport direction are calculated.

Step SP09 is a process performed in parallel with step SP05. In step SP09, the sensor device SEN3 detects the opposite first surface FE1 via the sensor device SEN2 and the web 120. That is, the first image pickup is performed on the first surface FE1 and the image data of the pattern is acquired.

In step SP10, the black sensor device SENK2 detects the first surface FE1 and acquires the image data of the pattern. It is desirable that the black sensor device SNK2 detects a position substantially the same as that of the sensor device SEN3.

In step SP11, the controller 520 performs a third correlation calculation based on the image data captured by the sensor device SEN3 and the black sensor device SENK2. As in step SP06, the result of the correlation calculation will be described as having calculated the amount of movement in the orthogonal direction and the amount of displacement of the position in the transport direction.

In step SP12, the controller 520 adds the amount of movement in the orthogonal direction calculated in step SP06 and the amount of movement in the orthogonal direction calculated in step SP11. Further, the amount of misalignment in the transport direction calculated in step SP06 and the amount of misalignment in the transport direction calculated in step SP11 are added. As a result, the amount of movement of the black liquid discharge head unit 210K in the orthogonal direction and the discharge processing timing of the black liquid discharge head unit 210K are calculated.

Since the following steps are the same, the description thereof will be omitted.

<Function configuration example>
FIG. 22 is a functional block diagram showing a functional configuration example of the transport device according to the third embodiment of the present invention. Compared with FIG. 19, in the third embodiment, the transfer device 100 is different in that the fourth detection unit 52G and the addition unit 58F are further provided.

The fourth detection unit 52G detects the first surface of the portion where the second detection unit 52E has acquired the image. The addition unit 58F acquires the result calculated by the calculation unit 53F based on the image data detected by the first detection unit 52D and the second detection unit 52E, and the fourth detection unit 52G and the third detection unit 52F. The result calculated by the calculation unit 53F based on the generated image data is added.

In the illustrated example, the detection results for controlling the movement and discharge timing of the black liquid discharge head unit 210K2 are determined by the first detection unit 52D, the second detection unit 52E, the third detection unit 52F, and the fourth detection unit 52G. Calculated based on the output.

In this example, the transport device 100 is positioned in double-sided printing based on the locations detected by the first detection unit 52D and the second detection unit 52E and the locations detected by the third detection unit 52F and the fourth detection unit 52G. Make adjustments, etc.

<Comparison example>
FIG. 23 is a schematic view showing an overall configuration example of the apparatus according to the comparative example. As shown in the figure, the device 110A of the comparative example has a configuration in which the roller 230 that conveys the web 120 is provided with the encoder 240. Then, in the device 110A of the comparative example, each liquid discharge head unit performs a process of discharging the liquid based on the measured amount measured by the encoder 240.

FIG. 24 is a diagram showing an example of the amount of deviation of the processing position by the apparatus of the comparative example. The figure shows an example of a shift in the position where the liquid discharged from each liquid discharge head unit is landed by the device 110A of the comparative example.

The first graph G1 shows the actual position of the web. On the other hand, the second graph G2 is the position of the web calculated based on the encoder signal from the encoder 240. That is, if there is a difference between the first graph G1 and the second graph G2, the position where the web is actually located and the calculated position of the web are different in the transport direction, so that the position where the liquid lands is deviated. Likely to happen.

For example, this is an example in which a deviation amount σ occurs in the liquid discharge by the black liquid discharge head unit 210K. Further, the amount of deviation may differ depending on the liquid discharge head unit. That is, in the discharge other than black, each deviation amount is often different from the illustrated deviation amount σ.

The amount of displacement is caused by, for example, eccentricity of the roller, thermal expansion of the roller, slippage between the web and the roller, expansion and contraction of the recording medium, and a combination thereof.

FIG. 25 is a diagram showing an example of the influence of the eccentricity of the roller on the deviation amount. The illustrated graph shows an example of the effects of roller thermal expansion, eccentricity and slippage between the roller and the web. That is, each graph shows the difference between the position of the web calculated based on the encoder signal from the encoder 240 and the actual position by the "deviation amount" on the vertical axis. Further, the figure shows an example in which the roller has an outer diameter of “φ60” and the material of the roller is aluminum.

The third graph G3 shows the deviation amount when the roller has an eccentricity amount of "0.01 mm". As shown in the third graph G3, the amount of deviation due to eccentricity is often a cycle synchronized with the rotation cycle of the roller. In addition, the amount of deviation due to eccentricity is often proportional to the amount of eccentricity, but it is often not cumulative.

The fourth graph G4 shows the amount of deviation when the roller has eccentricity and thermal expansion. The thermal expansion is an example when there is a temperature change of "-10 ° C.".

The fifth graph G5 shows the amount of deviation when the roller has an eccentricity and a slip generated between the web and the roller. The slip generated between the web and the roller is an example when it is "0.1%".

Further, in order to reduce meandering of the web, so-called tension may be applied to pull the web in the transport direction. Depending on this tension, the web may stretch or contract. Further, the expansion and contraction of the web may differ depending on the thickness, width, coating amount and the like of the web.

<Summary>
With the transfer device according to the embodiment of the present invention, alignment in double-sided printing can be performed. Specifically, since the same location as the location for the first processing performed upstream can be detected by the sensor even in the downstream where the second processing is performed, the transport device can be used even if there is no mark for alignment, a so-called register mark. , Alignment is possible in double-sided printing. Therefore, the transport device can remove the liquid and the margin portion for forming the register mark, and can improve the productivity.

<Modification example>
FIG. 26 is a schematic view showing a modified example of the configuration of an apparatus that performs image formation processing according to an embodiment of the present invention. As compared with FIG. 2, in the illustrated configuration, the arrangement of the first support member and the second support member is different. As shown in the figure, the first support member and the second support member may be realized by, for example, the first member RL1, the second member RL2, the third member RL3, the fourth member RL4, and the fifth member RL5. .. That is, the second support member provided on the upstream side of each liquid discharge head unit and the first support member provided on the downstream side of each liquid discharge head unit may be shared. The first support member and the second support member may be combined with a roller or a curved plate. Since the same applies to 10M2, the description of 10M2 will be omitted.

Further, the present invention can be applied to an apparatus that performs some processing by using line-shaped head units arranged in an orthogonal direction.

For example, the embodiment according to the present invention may be a transfer device or the like in which a head unit emits a laser and the substrate to be transported is subjected to patterning processing by the laser. Specifically, the transport device first has laser heads arranged in a line in an orthogonal direction. Then, the transport device detects the position of the substrate and the like, and moves the head unit or the like based on the detection result. Further, in this example, the processing position is the position where the laser irradiates the substrate.

In addition, in the embodiment of the present invention, the head unit may perform a reading process for reading an image formed on the object to be conveyed. That is, when the head unit is a so-called scanner or the like, the head unit can read an image formed on an object to be transported and generate image data. In this example, the processing position is the position where the head unit reads the image formed on the object to be transported.

Further, the transport device does not have to have a plurality of head units. That is, the present invention is applicable when the processing is continuously performed at the reference position with respect to the transported object.

<Other embodiments>
The light source is not limited to the one using a laser beam. For example, the light source may be an LED (Light Emitting Diode), an organic EL (Electro-Luminescence), or the like. And, depending on the light source, the pattern does not have to be a speckle pattern.

Further, the light source may be a light source having a single wavelength or a light source having a broad wavelength.

In the above embodiment, an image forming apparatus for forming an image using a liquid ejection head unit having four colors of black, cyan, magenta, and yellow has been described as an example. However, the image forming apparatus may be configured to include, for example, a plurality of black liquid ejection head units to form an image.

Further, the object to be transported is not limited to a recording medium such as paper. The transported object may be made of a material to which a liquid can adhere. For example, the material to which the liquid can be attached may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics, or a combination thereof, as long as the liquid can be attached even temporarily.

The embodiment may be realized by a transport system having one or more devices. For example, the black liquid discharge head unit and the cyan liquid discharge head unit are devices in the same housing, and the magenta liquid discharge head unit and the yellow liquid discharge head unit are devices in the same housing, which are realized by a transfer system having both of them. May be done.

Further, each process may be performed in parallel, redundantly or distributed by a plurality of information processing devices included in the transport system.

Further, in the transport device and the transport system according to the present invention, the liquid is not limited to ink, but may be another type of recording liquid, fixing treatment liquid, or the like. That is, the transport device, the image forming device, and the transport system according to the present invention may be applied to a device that ejects a liquid of a type other than ink.

Therefore, the transport device, the image forming device, and the transport system according to the present invention are not limited to the process of forming an image. For example, the formed object may be a three-dimensional model or the like.

Further, in the embodiment of the present invention, it may be realized by a program for causing a computer such as a transfer device, an image forming device, and a transfer system to execute a processing method. Therefore, when the processing method is executed based on the program, the arithmetic unit and the control unit of the computer perform the arithmetic and control based on the program in order to execute each processing. In addition, the storage device of the computer stores the data used for the processing based on the program in order to execute each processing.

The program can also be recorded and distributed on a computer-readable recording medium. The recording medium is a medium such as a magnetic tape, a flash memory, an optical disk, a magneto-optical disk, or a magnetic disk. In addition, the program can be distributed over telecommunication lines.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. That is, various modifications or changes are possible within the scope of the gist of the present invention described in the claims.

100 Conveyor 120 Web 210K Black Liquid Discharge Head Unit 210C Cyan Liquid Discharge Head Unit 210M Magenta Liquid Discharge Head Unit 210Y Yellow Liquid Discharge Head Unit SENK Black Sensor Device SENC Cyan Sensor Device SENM Magenta Sensor Device SENY Yellow Sensor Device 520 controller

Japanese Unexamined Patent Publication No. 2015-13476

Claims (12)

An image forming device that forms an image on the object to be transported.
A first detection unit that detects surface information on the first or second surface of the object to be transported, and
A first head unit that forms an image on the first surface of the object to be transported based on the detection result of the first detection unit, and
A second detection unit that detects surface information on the same surface as the first detection unit, and
A second head unit that forms an image on a second surface different from the first surface based on the detection results of the first detection unit and the second detection unit.
A moving unit that moves the first head unit and the second head unit based on the detection result, and
An image forming apparatus. The first detection unit detects the second surface and
The second detection unit detects the second surface and
The first detection unit is provided on the side opposite to the side on which the first head unit is installed so as to sandwich the object to be transported.
The image forming apparatus according to claim 1, wherein the second detection unit is provided on the same side as the side on which the first head unit is installed . The first detection unit detects the second surface and
The second detection unit detects the second surface and
The image forming apparatus according to claim 1, further comprising a third detection unit that detects the first surface downstream of the second detection unit. The image forming apparatus according to claim 3, further comprising a fourth detection unit that detects the first surface upstream of the third detection unit. Claims 1 to 4 further include an inversion portion that inverts the first surface and the second surface between the image formation by the first head unit and the image formation by the second head unit. The image forming apparatus according to any one of the following items. The image forming apparatus according to any one of claims 1 to 5, which detects a pattern on the surface of the object to be transported as the surface information. The image forming apparatus according to any one of claims 1 to 6, which is generated by the interference of light applied to the uneven shape formed on the object to be conveyed as the surface information. A first support member installed upstream of the processing position where the first head unit or the second head unit performs image formation and used to convey the object to be conveyed to the processing position.
It is provided with a second support member installed downstream from the processing position and used to transport the object to be transported from the processing position.
The image forming apparatus according to any one of claims 1 to 7, further comprising one or more detection units between the first support member and the second support member. The image forming apparatus according to claim 8, wherein the detection unit is provided between the processing position and the first support member. The image forming apparatus according to any one of claims 1 to 9, wherein the processing timing in which the first and second head units perform image forming is controlled based on the detection result. The first detection unit and the second detection unit each have a light source.
The image forming apparatus according to any one of claims 1 to 10, wherein the light source is an LED or an organic EL. It is an image forming method performed by an image forming apparatus that forms an image on an object to be conveyed.
The first detection procedure for detecting the surface information of the first surface or the second surface of the object to be transported, and
A first processing procedure in which the first head unit forms an image on the first surface of the object to be transported based on the detection result of the first detection procedure.
A second detection procedure for detecting surface information on the same surface as the first detection procedure, and a second detection procedure.
A second processing procedure in which the second head unit forms an image on a second surface different from the first surface based on the detection results of the first detection procedure and the second detection procedure.
A movement procedure for moving the first head unit and the second head unit based on the detection result, and
Image forming method including.

Images