This application is based on and claims priority under 35 U.S.C. 119 from Japanese Patent Application Nos. 2015-160102 filed on Aug. 14, 2015, 2015-153361 filed on Aug. 3, 2015, and 2015-153360 filed on August 3.
1. Technical Field
This invention relates to a winding device and an image forming device.
2. Related Art
A winding device for web-like print, described in JP-A-2003-128313, winds a web-like print while shifting the web-like print to a scanning direction, and thereby the both end surfaces of the wound print are arranged to be non-uniform.
According to an exemplary embodiment of the present invention, there is provided a winding device, including: a winding part that winds a longitudinal recording medium in which an image is formed; a suppressing member that suppresses generation of a strain in the longitudinal recording medium wound by the winding part; and an operation part that operates the suppressing member in a case where the strain in the longitudinal recording medium wound by the winding part is a threshold value or more.
Exemplaty embodiments of the present invention will be described in detail based on the following figures, wherein:
An example of a winding device and an image forming apparatus according to the first embodiment of the present invention will be explained according to
As shown in
The image forming apparatus 10 includes a post-processing unit 18 accommodating the resin film F discharged from the image forming unit 12, and a buffer unit 20 provided between the image forming unit 12 and the post-processing unit 18 and adjusting a transfer amount or the like of the resin film F discharged from the image forming unit 12 to the post-processing unit 18.
An example of the resin film of the first embodiment of the present invention is made from polyethylene terephthalate and has a thickness of 15 μm and a width of 508 mm.
The image forming unit 12 includes image forming parts 26Y, 26M, 26C and 26K as an examples of image forming parts of yellow (Y), magenta (M), cyan (C) and black (K), and a fixing device 30. Meanwhile, in the following explanation, in a case where Y, M, C and K do not need to be distinguished, Y, M, C and K are abbreviated in some cases.
The each image forming part 26 includes an image support member 36, a charging roller 38 for charging the surface of the image support member 36, and an exposing device 42 for irradiating light for exposure to the charged image support member 36.
The each image forming part 26 further includes a developing device 40 for developing an electrostatic latent image formed on the image support member 36 by the exposure performed by the exposing device 42 to visualize it as a toner image, and a transfer roller 44 for transferring the toner image formed on the image support member 36 to the resin film F.
The pre-processing unit 14 includes a feeding roller 22 to which the resin film F to be fed to the image forming unit 12 is wound, as shown in
The post-processing unit 18 includes a winding device 24 for winding the resin film F on which an image has been formed.
The winding device 24 includes, as shown in
The winding device 24 also includes a control member 32 for controlling each member as shown in
The reason for formation of the projection portion 100 on the resin film is described below. An image part 102 on the resin film F, in which an image has been formed, becomes thicker than a non-image part 104, in which an image was not formed, as shown in
The winding shaft 28 is provided so as to extend to the depth direction of the device as shown in
The projection portion suppressing member 46 includes, as shown in
The support member 54 includes a pair of vertical plates 54A sandwiching the resin film F wound by the winding shaft 28 in the depth direction of the device, and a linking plate 54B linking the lower ends of the pair of vertical plates 54A and extending to the depth direction of the device. The winding shaft 28 is supported, at the both end sides thereof, by the pair of vertical plates 54A via a bearing 59.
The guide part 56 supports the linking plate 54B of the support member 54 from the lower side and makes the support member 54 movable to the depth direction of the device.
The biasing spring 60 is provided between a frame member 90 at the far side (i.e., right side in
The cum part 64 is provided at the front side of the depth direction of the device with respect to the support member 54 and includes a cum member 66 of which the surface is in contact with the vertical plate at the front side of the depth direction of the device, and a motor 68 for rotating the cum member 66.
The rotation part 48 includes a motor 50 equipped with the vertical plate 54A at the front side of the depth direction of the device, and a gear group 52 that transmits a rotational force of the motor 50 to the winding shaft 28.
In this configuration, in a case where the motor 50 makes the winding shaft 28 rotate to wind the resin film F, the motor 68 rotates the cum member 66. By rotating the cum member 66, the support member 54 and the winding shaft 28 supported by the support member 54 can reciprocate to the depth direction of the device. Then, the winding shaft 28 reciprocating to the depth direction of the device winds the resin film F. In this case, in the resin film F wound by the winding shaft 28, the image portion 102 in which an image has been formed does not overlap at the same position in the shaft direction (see
The projection portion measurement member 70 includes, as shown in
The projection portion measurement member 70 also includes a swing part 78 for moving the measurement instrument 86 in an approaching and separating direction with respect to the resin film F so that a distance between the measurement instrument 86 and the resin film falls within a specific range.
The swing part 78 includes a pair of support bars 80 extending to a direction crossing the rail member 88 and arranged at the both ends of the rail member 88, and a rotation shaft 82 that is arranged at each one end of the support bars 80, extends to the depth direction of the device, and supports the pair of the support bars 80.
Each of the support bars 80 is bent at the other side into L-shape. The rollers 84 are arranged at the tip end of the portion bent into L-shape to be in contact with the both end.
In this construction, the driven member moves the measurement instrument 86 from one end to the other end of the rail member 88 per a fixed time. That is, the measurement instrument 86 moves from one end to the other end of the wound resin film F. The measurement instrument 86 detects the presence or absence of the projection portion (see
The control member 32 includes a diameter calculation part 74 for calculating a diameter of the resin film F, a strain calculation part 72 for calculating a strain generated in the resin film F due to the projection portion formed on the resin film F, and an operation part 76 for operating the projection portion suppressing member 46.
The diameter calculation part 74 always calculates a wound diameter (Rn) of the resin film F from a length (L) of the resin film F wound by the winding shaft 28, a thickness (tn) of the resin film F, and a half diameter (r) of the winding shaft 28 (see
Specifically, a user inputs the thickness (tn) of the resin film and the half diameter (r) of the winding shaft into the winding device from an input part not shown in the figure, and thereby the diameter calculation part 74 obtains the diameter (tn) and the half diameter (r). Also, a transfer rate of the resin film F is predetermined, and the control member 32 obtains it. The diameter calculation part 74 calculates the length (L) of the resin film F wound by the winding shaft from the transfer rate (V) of the resin film F and a time measured with a timer not shown in the figure.
The diameter calculation part 74 can calculate the wound diameter (Rn) of the resin film F from the following equation (1).
Rn=√{square root over (r2+(L·tn)/π)} Equation (1)
The strain calculation part 72 calculates a strain (ε) of the resin film F at the projection portion 100 from the projection height (S) of the projection portion 100 measured by the projection portion measurement member 70, and the winding diameter (Rn) of the resin film F calculated by the diameter calculation part 74.
Specifically, the strain calculation part 72 calculates the strain (ε) of the resin film F at the projection portion 100 from the following equation (2).
ε=S/Rn Equation (2)
The operation part 76 operates the projection portion suppressing member 46 in a case where the strain (ε) calculated from the strain calculation part 72 is a predetermined threshold value or more.
This threshold value is set so that even when the resin film F is partially strained due to the projection portion 100 formed on the resin film F, the strain does not become wrinkle (permanent deformation).
Even in a case where the strain (ε) becomes less than the threshold value during operation of the projection portion suppressing member 46, the operation part 76 goes on operating the projection portion suppressing member 46.
Subsequently, an operation of the winding device 24 will be explained while comparing to a winding device 200 according to a first comparative example.
The winding device 24 winds the resin film F on which an image has been formed when the image forming apparatus 10 operates, and transfers the resin film F along a transferring path 58 (see
Also, the driving member not shown in the figure moves the measurement instrument 86 from one end to the other end of the rail member 88 per a fixed time as shown in
The strain calculation part 76 calculates a strain (ε) of the resin film from the projection height (S) measured by the measurement instrument 86, and the wound diameter (Rn) of the resin film F calculated by the diameter calculation part 74.
The operation part 76 operates the projection portion suppressing member 46 in a case where the strain (ε) is the predetermined threshold value or more. By this, the motor 68 shown in
Thus, the winding shaft 28 reciprocating in the depth direction of the device winds the resin film F, and thereby in the resin film F wound by the winding shaft, an image part 102 on which an image has been formed does not overlap at the same position in the shaft direction. Due to this, the projection portion 100, which is a factor of wrinkle, is suppressed from being formed at the surface of the resin film F wound by the winding shaft 28.
Since the winding shaft 28 winds the resin film F while reciprocating in the depth direction of the device, the both end surfaces 106 of the resin film F wound by the winding shaft 28 is arranged to be non-uniform as shown in
In the ease where the strain (ε) is less than the predetermined threshold value, the winding shaft 28 does not move in the depth direction of the device. For that, the both end surfaces 106 of the resin film F wound by the winding shaft 28 is arranged to be uniform.
Here, in the winding device 200 according to the first comparative embodiment, in a case where the image forming apparatus 10 operates, the motor 68 shown in
Thus, in the winding device 200, the winding shaft 28 winds the resin film while always reciprocating in the depth direction of the device, and therefore the both end surfaces 206 of the resin film F are arranged to be non-uniform from the start of the winding to the end of the winding as shown in
As explained above, the winding device 24 operates the projection portion suppressing member 46 in a case where the strain (ε) of the projection portion 100 is a predetermined threshold value or more. In other words, in an only case where there is a possibility that the projection portion 100, which is a factor of wrinkle, is formed on the wound resin film F, the operation part 76 operates the projection portion suppressing member 46. That is, in an only case where there is a possibility that a strain is generated in the wound resin film F, the projection portion suppressing member 46 operates.
In a case where there is no possibility that the projection portion 100, which is a factor of wrinkle, is formed, the operation part 76 does not operate the projection portion suppressing member 46. In this case, as shown in
The projection portion measurement member 70 measures the projection height (S) of the resin film F by using the measurement instrument 86, and therefore a strain of the projection portion 100 (ε) is measured with a high accuracy compared to a case of calculating the projection height (S) of the projection portion 100.
In the image forming apparatus 10, in an only case where there is a possibility that the projection portion 100, which is a factor of wrinkle, is formed on the wound resin film F, the operation part 76 operates the projection portion suppressing member 46. Thus, compared to a case where the projection portion always operates, consumption energy is reduced.
Examples of a winding device and an image forming apparatus according to the second embodiment of the present invention will be explained according to
A winding device 250 according to the second embodiment does not include a projection portion measurement member, and a control member 252 of the winding device 250 includes the projection portion calculation part 256 as shown in
The projection portion calculation part 256 obtains a wound diameter (Rc) by using the following equation (3) from the rotational speed (ωi) of the winding shaft 28, and the transfer rate (V) of the resin film F (see
Rc=V/ω1 Equation (3)
Further, the projection portion calculation part 256 calculates a projection height (S) of the projection portion 202 from the following equation (4).
S=(Rc−Rn)*2 Equation (4)
In this construction, the strain calculation pan 72 calculates a strain (ε) of the resin film F from the projection height (S) calculated by the projection portion calculation part 256, and the wound diameter (Rn) of the resin film F.
As explained above, the projection portion calculation part 256 calculates the projection height (S) of the projection portion 202 by using the rotational speed (ωi) of the winding shaft 28, and the transfer rate (V) of the resin film F. That is, the projection portion calculation part 256 calculates the projection height (S) without using an apparatus such as the projection portion measurement member 70 of the first embodiment. By this, compared to a case where the projection height (S) of the projection portion 100 is measured, a strain (ε) of the projection portion 100 may be obtained by a simple construction.
The other operations of the second embodiment are the same as in the first embodiment, except an operation that the projection portion 202 is measured by using the measurement instrument 86.
The first and second embodiments of the present invention have been explained in detail, but the present invention is not limited thereto. It is apparent to a person skilled in the art that various modifications can be available without exceeding the range of the present invention. For example, the wound diameter (Rn) of the resin film F is calculated by the diameter calculation part 74 in the above embodiments, but the wound diameter may be directly measured by using a laser displacement meter or the like.
Also, a particular explanation has not been made in the first and second embodiments, when the resin film F is wound by the winding shaft 28, an air layer is present between the resin films in sonic cases. In this case, a thickness of the resin film F may be considered as a total thickness of the resin film F and the air layer and may be used for calculation.
In the first and second embodiments, the projection portions 102 and 202 formed by the presence of an image have been explained particularly, but a projection portion may be formed, for example, due to deformation caused by heating the resin film F.
In the first and second embodiments, the resin film F is made from polyethylene terephthalate, but the resin film F may be made from polypropylene, polystyrene, or the like.
In the first and second embodiments, a recording medium is the resin film F, but the recording medium may be paper or the like.
In the first and second embodiments, the winding shaft 28 reciprocating in the depth direction of the device winds the resin film F, and thereby formation of the projection portion 100 or 202 on the resin film F is suppressed. However, for example, the formation of the projection portion 100 or 202 on the resin film F may be suppressed by controlling a wound tension of the winding device (specifically, when the tension is weaken, the effect of the present invention can be obtained). Also, the projection portion suppressing member may issue a warning to notify a user a possibility that the projection portion 100 or 202 may be formed. Due to this warning, the user operates the winding shaft 28 to reciprocate in the shaft direction so as to suppress the formation of the projection portion 100 or 202 on the resin film.
In the first and second embodiments, an image is formed on the resin film F by an electrographic method, but an inkjet method, a gravure method or the like may be available to form an image.
An example of an image forming apparatus according to the third embodiment of the present invention will be explained according to
As shown in
The image forming apparatus 100 includes a post-processing unit 180 accommodating the resin film F discharged from the imam forming unit 120, and a buffer unit 200 provided between the image forming unit 120 and the post-processing unit 180 and adjusting a transfer amount or the like of the resin film F discharged from the image forming unit 120 to the post-processing unit 180. The image forming apparatus 100 also includes a control member 320 as an example of operation part for controlling each part.
An example of the resin film of the first embodiment of the present invention is made from polyethylene terephthalate and has a thickness of 15 μm and a width of 508 mm.
The image forming unit 120 includes image forming parts 260Y, 260M, 260C and 260K as an examples of image forming parts of yellow (Y), magenta (M), cyan (C) and black (K), and a fixing device 300. Meanwhile, in the following explanation, in a case where Y, M, C and K do not need to be distinguished, Y, M, C and K are abbreviated in some cases.
The each image forming part 260 includes, as shown in
The each image forming part 260 further includes a developing device 400 for developing an electrostatic latent image formed on the image support member 360 by the exposure performed by the exposing device 420 to visualize it as a toner image, and a transfer roller 440 for transferring the toner image formed on the image support member 360 to the resin film F. Also, the fixing device 300 (see
The pre-processing unit 140 includes a feeding roller 220 to which the resin film F to be fed to the image forming unit 120 is wound, as shown in
The post-processing unit 180 includes a winding shaft 280 as one example of a winding part extending to the depth direction of the device and being capable of winding the resin film F on which an image has been formed, by receiving a rotational force from a motor not shown in the figure.
The post-processing unit 180 includes, as shown in
The support member 540 includes a pair of vertical plates 540A sandwiching the resin film F wound by the winding shaft 280 in the depth direction of the device, and a linking plate 540B linking the lower ends of the pair of vertical plates 540A and extending to the depth direction of the device. The winding shaft 280 is supported, at the both end sides thereof, by the pair of vertical plates 540A via a bearing 580.
The guide part 560 supports the linking plate 540B of the support member 540 from the lower side and makes the support member 540 movable to the depth direction of the device.
The biasing spring 600 is provided between a frame member 900 at the far side (i.e., right side in figure) of the depth direction of the device with respect to the support member 540 and the vertical plate 540A at the far side of the depth direcfion of the device for biasing the support member 540 to the front side of the depth direction of the device.
The cum part 640 is provided at the front side of the depth direction of the device with respect to the support member 540 and includes a cum member 660 of which the surface is in contact with the vertical plate at the front side of the depth direction of the device, and a motor 680 making the cum member 660 rotate.
The rotation part 800 includes a motor 820 equipped with the vertical plate 540A at the front side of the depth direction of the device, and a gear group 840 that transmits a rotational force of the motor 800 to the winding shaft 280.
The suppressing member 700 for suppressing the formation of the projection portion (described later in detail) on the resin film F includes the guide member 560, the biasing spring 600 and the cum part 640.
Control of the motor 820 and suppressing member 700 performed by the control member 320 will be explained together with operation of the image forming apparatus according to the third embodiment of the present invention.
Subsequently, an operation of the image forming apparatus 100 will be explained by using the flow diagram of
In a case Where an image is formed on the resin film F, the control member 320 receives one print instruction (ono print job) for forming a plurality of images on the resin film F at the step 100. After the control member 320 receives the one print instruction, the flow proceeds to the step 200.
At the step 200, the control member 320 calculates an image density in each section into which the resin film F is divided in the width thereof based on image data output by the one print instruction. The image density means a ratio of colored dots to the total dots in the region, and in a case of the total dots in the region are colored (beta-image), the ratio is 100%.
For example, the control member 320 divides image data for forming one image as shown in
After the control member 32 calculates the image density in each section, the flow proceeds to the step 300. Meanwhile, in the working examples, a plurality of images output by the one print instruction is the image shown in
In the step 300, the control member 320 compares image densities in adjacent sections to each other and determines the difference of their image densities is equal to or greater than a threshold value or not. In the case where the difference is equal to or greater than the threshold value or more, the control member 320 determines that there is a possibility that a projection portion is formed on the resin film F. Here, the projection portion means a projection portion formed on the resin film F wound by the winding shaft 280 and extending to the circumferential direction of the wound resin film F due to difference of the image densities of an image which has been formed on the resin film F (step in the width direction of the resin film). Specifically, at a portion where an image density is high, a thickness thereof becomes thicker than a portion where an image density is low. In a case where the resin film F is wound by the winding shaft so that the portion where an image density is high overlaps at the same position in the shaft direction, a projection portion extending to the circumferential direction of the wound resin film F is formed on the resin film F. And then, the projection portion leads to a partial strain of the resin film F. when the resin film F is taken out from the winding shaft 280, this strain remains in the resin film F as a wrinkle in some cases.
In the case where the difference of the image densities in adjacent sections is equal to or greater than the threshold value or more, the flow proceeds to the step 400, and in the case where the difference of the image densities in adjacent sections is less than the threshold value, the flow proceeds to the step 450.
In the step 400, the control member 320 operates the image forming unit 120 of each color (see
By this, the motor 820 rotates the winding shaft 280, the rotated winding shaft 280 finds the resin film F. Further, the motor equipped with the suppressing member 700 rotates the com member 660, and the rotated cum member 660 makes the support member 540 and the winding shaft 280 supported by the support member 540 reciprocate.
Thus, by reciprocating the winding shaft in the depth direction of the device, a margin for overlapping, in the shaft direction, regions in which image densities are high becomes small. By this, the formation of the projection portion on the resin film F is suppressed.
Then, all images output by the one print image are formed on the resin film F. After the winding shaft 280 winds the resin film F on which the images have been formed, the control member 320 completes the operation for forming an image.
Thus, the winding shaft 280 winds the resin film F while reciprocating in the depth direction of the device, and therefore the both end surfaces 1060 of the resin film F wounded by the winding shaft 280 are arranged to be non-uniform.
On the other hand, as explained above, in the case where the difference of the image densities in adjacent sections is less than the threshold value or more, the flow proceeds to the step 450.
In the step 450, the control member 320 determines whether any of image densities in the sections is equal to or greater than a threshold value. By this, in the case where any of image densities in the sections is equal to or greater than the threshold value, the control member 320 determines that there is a possibility that a projection portion is thrilled on the resin film F.
In the case where any of image densities in the sections is equal to or greater than the threshold value, the flows proceeds to the step 400, and in the step 400, the above explained process is performed. On the other hand, in the case where image densities of the all sections are less than the threshold value, the flow proceeds to the step 550.
In the step 550, the control member 320 operates the image forming unit 120 of each color (see
By this, the motor 82 rotates the winding shaft 28, and the rotated winding shaft 28 winds the resin film F. Then, all images output by the one print instruction are formed on the resin film F. After the winding shaft 280 winds the resin film F on which the images have been formed, the control member 320 completes the operation for forming an image.
Thus, the winding shaft 280 not reciprocating in the depth direction of the device winds the resin film F, and therefore the both end surfaces 1060 of the resin film F wound by the winding shaft 280 are arranged to be uniform as shown in
Here, in an image forming apparatus according to the comparative embodiment, a control member (omitted in the figure) operates the image forming unit 120 of each color (see
By this, the winding shaft 28 reciprocating in the depth direction of the device winds the resin film F. Then, all images output by the one print instruction are formed on the resin film F. After the winding shaft 280 winds the resin film F on which the images have been formed, the control member completes the operation for forming an image.
Thus, in the image forming apparatus according to the second comparative embodiment, the winding shaft 280 winds the resin film while reciprocating in the depth direction of the device, and therefore the both end surfaces 1060 of the resin film F are always arranged to be non-uniform regardless of image density (see
As explained above, the control member 320 in the image forming apparatus 100 determines, in the step 300, whether or not the difference of image densities of adjacent sections is a threshold value or more. The control member 320 also determines, in the step 450, whether or not the image densities in the any of sections are a threshold value or more. In the case where the control member 320 determines there is a possibility that a projection portion is formed on the resin film F, the control member 320 operates the suppressing member 700.
On the other hand, in the case where the control member determines there is no possibility that a projection portion is formed on the resin film F, the control member 320 does not operate the suppressing member 700. Thus, the control member 320 determines there is no possibility that a projection portion is formed on the resin film, the both end surfaces 106 of the resin film F wound by the winding shaft 280 are arranged to be non-uniform as shown in
On contrary, in an image forming apparatus according to the second comparative embodiment, the winding shaft 280 reciprocating in the depth direction of the device winds the resin film F, and therefore the both end surfaces 1060 of the resin film F wound by the winding shaft 280 are always arranged to be non-uniforin regardless the image density. In other words, in the image forming apparatus according to the second comparative example imparts, the winding shaft 280 winds the resin film F while reciprocating in the depth direction of the device even in a case where there is low possibility that a projection portion is formed on the resin film F, and therefore the both end surfaces 1060 are always arranged to be non-uniform. On the other hand, in the image forming apparatus 100, in the case where the control member 320 determines there is no possibility that a projection portion is formed on the resin film F, as explained above, the both end surfaces 1060 of the resin film F are arranged to be uniform. Thus, in the case where there is low possibility that a projection portion is formed on the resin film F, the non-uniform arrangement of the both end surfaces of the resin film F is suppressed.
The control member 320 determines, in the step 450, there is a possibility that a projection portion is thrmed on the resin film F in a case where any of image densities in the sections is a threshold value or more. Thus, since the control member 320 determines the possibility of the formation of the projection portion on the resin film F based on the image density in each section, the possibility of the formation of the projection portion on the resin film F is determined in higher accuracy compared to a case where the suppressing member operates only when the diMrence of image densities in adjacent sections is a threshold value or more.
The third embodiment of the present invention has been explained in detail, but the present invention is not limited thereto. It is apparent to a person skilled in the art that various modifications can be available without exceeding the range of the present invention. For example, in the third embodiment, a plurality of images is formed on the resin film F by one print instruction, but only one image may be formed on the resin film F by one print instruction.
In the third embodiment, all of the plurality of images formed on the resin film F by one print instruction are the same, but the plurality of images thrmed on the resin film F by one print instruction may be different.
Also, in the third embodiment, the image forming apparatus determines there is a possibility that a projection portion is formed on the resin film F based on difference of image densities in adjacent sections, but for example, the image forming apparatus may determine there is a possibility that a projection portion is formed on the resin film F by comparing the highest image density and the lowest image density among all image densities in the sections.
In the first and second embodiments, the resin film F is made from polyethylene terephthalate, but the resin film F may be made from polypropylene, polystyrene, or the like.
In the first and second embodiments, a recording medium is the resin film F, but the recording medium may be paper or the like.
In the first and second embodiments, the winding shaft 280 reciprocating in the depth direction of the device winds the resin film F. However, for example, the suppressing member may issue a warning to notify a user a possibility that a projection portion is formed. Due to this warning, the user operates the winding shaft 280 to reciprocate in the shaft direction so as to suppress the formation of the projection portion on the resin film.
In the third embodiment, the control member 320 divides image data into 10 sections in the width direction of the resin film F (G direction in the figure), but the divided section may be 10 or more or less than 10.
In the third embodiment, an image is formed on the resin film F by an electrographic method, but an inkjet method, a intaglio printing method or the like may be available to form an image.
In the third embodiment, the control member 320 determines, in the step 450, whether or not any of image densities in the sections is a threshold value or more, but in the case where the difference of image densities in adjacent sections is less than a threshold value in the step 300, the flow may directly proceed to the step 550.
An example of an image forming apparatus according to the fourth embodiment of the present invention will be explained according to
As shown in
The image forming apparatus 1000 includes a post-processing unit 1800 accommodating the resin film F discharged from the image forming unit 1200, and a buffer unit 2000 provided between the image forming unit 1200 and the post-processing unit 1800 and adjusting a transfer amount or the like of the resin film F discharged from the image forming unit 1200 to the post-processing unit 1800.
The image forming unit 1200 includes image forming parts 2600Y, 2600M, 2600C and 2600K as an examples of image forming parts of yellow (Y), magenta (M), cyan (C) and black (K), and a fixing device 3000. Meanwhile, in the following explanation, in a case where Y, M, C and K do not need to be distinguished, Y, M, C and K are abbreviated in some cases.
The each image forming part 2600 includes, as shown in
The each image forming part 2600 further includes a developing device 4000 for developing an electrostatic latent image formed on the image support member 3600 by the exposure performed by the exposing device 420 to visualize it as a toner image, and a transfer roller 4400 for transferring the toner image formed on the image support member 3600 to the resin film F. Also, the fixing device 3000 (see
A position of an image formed on the resin film F by each image forming part 2600 of each color will be explained below in detail.
The pre-processing unit 1400 includes a feeding roller 2200 to which the resin film F to be fed to the image forming unit 1200 is wound, as shown in
The post-processing unit 1800 includes a winding shaft 2800 as one example of a winding part capable of winding the resin film F on which an image has been formed, by receiving a rotational fbrce from a motor not shown in the figure.
In this construction, by rotating the winding shaft 2800, a tension in a paper-feeding direction is imparted to the resin film F, and thereby the resin film F is fed to a transferring path 2400.
Subsequently, a position of an image formed on the resin film F by each image forming part 2600 of each color will be explained. An example of the resin film of the first embodiment of the present invention is made from polyethylene terephthalate and has a thickness of 15 μm and a width of 508 mm.
The image forming part 2600 forms a latter image 101B by being shifted in the width direction of the resin film F with respect to a former image 101A.
Specifically, the image forming part 2600 shifts a position of an electrostatic latent image formed on an image support member 3600 by an exposure device (see
The image forming part 2600 forms a plurality of images on the resin film F while being shifted in a wavy tbrm (for example, sine-curve shape, zigzag shape). As one example of the fourth embodiment, amplitude of the wavy form is in a range of 2 mm or more and 10 mm or less. In the case where the amplitude is less than 2 mm, effects for suppression of formation of a projection portion become small as explained below, and in the case where the amplitude is more than 10 mm, a problem is caused during a slit process or the like, which is a post-processing, in some cases. Further, a period of the wavy form is a length of the resin film F wounded by 10 rotations (initial 10 rotations) of the winding shaft 28.
A shifted amount (size G in
Here, the softness of the resin film F is compared based on an elongation of the resin film F. Specifically, a test piece S with a length (L) of 150 mm and a width (W) of 15 mm is cut out from the resin film F (see
In the image forming apparatus according to the fourth embodiment, an operation obtained by the formation of the latter image 101B by being shifted in the width direction of the resin film F with respect to the former image 101A on the resin film F will be explained.
Initially, constructions and operations of an image forming apparatus 300 according to the third comparative embodiment and an image forming apparatus 350 according to the fourth comparative embodiment will be explained. With respect to the image forming apparatuses 300 and 350 according to the third comparative embodiment and the fourth comparative embodiment, respectively, differences from the fourth embodiment of the present invention will be explained mainly.
In the image forming apparatus 300 according to the third comparative embodiment, the latter image 100B is not shifted in the width direction of the resin film with respect to the former image 101A, as shown in
Due to this construction, a projection portion 306 is formed on the surface of the resin film F wound by the winding shaft, as shown in
Thus, the projection portion 306 is formed on the surface of the resin film wound by the winding shalt, and owing to the both end portions 306A of the projection portion 306, the resin film F is strained. When the resin film F is taken out from the winding shaft 2800 after completion of image forming operation, this strain remains on the resin film F as a wrinkle.
The image forming apparatus 350 according to the fourth comparative embodiment, the latter image 101B is not shifted in the width direction of the resin film with respect to the former image 101A, as shown in
Specifically, the image forming apparatus 350 includes a support member 354 for supporting portions at the both end sides of the winding shaft 2800, and a rail member 356 for supporting the support member 354 so that the support member 354 is movable in the depth direction of the device. Further, the image forming apparatus 350 includes a biasing spring 360 for biasing the support member 354 to the front side (left side in the figure) in the depth direction of the device, a cum part 364 for reciprocating the support member in the depth direction of the device, and a rotation part 380 for rotating the winding shaft 2800.
The support member 354 includes a pair of vertical plates 354A sandwiching the resin film F wound by the winding shaft 2800 in the depth direction of the device, and a linking plate 354B for linking the lower ends of the pair of vertical plates 354A and extending to the depth direction of the device. The winding shaft 2800 is supported, at the both end sides thereof, by the pair of vertical plates 354A via a bearing not shown in the figure.
The rail part 356 supports the linking plate 354B of the support member 354 from the lower side and makes the support member 354 movable to the depth direction of the device.
The biasing spring 360 is provided between a frame member 390 at the far side (i.e., right side in the figure) of the depth direction of the device with respect to the support member 354 and the vertical plate 354A at the far side of the depth direction of the device for biasing the support member 354 to the front side of the depth direction of the device.
The cum part 364 is provided at the front side of the depth direction of the device with respect to the support member 354 and includes a cum member 366 of which the surface is in contact with the vertical plate at the front side of the depth direction of the device, and a motor 368 for rotating the cum member 366.
The rotation part 380 includes a motor 382 equipped with the vertical plate 354A at the front side of the depth direction of the device, and a gear group 384 that transmits a rotational tbrce of the motor 382 to the winding shaft 28.
In this construction, in a case where the motor 382 makes the winding shaft 2800 rotate to wind the resin film F, the motor 368 rotates the cum member 366. By rotating the cum member 366, the support member 354 and the winding shaft 2800 supported by the support member 354 can reciprocate to the depth direction of the device. Then, the winding shaft 28 reciprocating to the depth direction of the device winds the resin film F.
Thus, by winding the resin film F by the winding shaft 2800 reciprocating in the depth direction of the device (as one example, the amplitude is 2 mm), in the resin film wound by the winding shaft, the high image density portion 104 in each image does not overlap at the same position in the shaft direction. By this, the formation of the projection portion on the surface the resin film F wound by the winding shaft 2800 is likely to be suppressed.
However, since the winding shaft 28 reciprocating in the depth direction of the device winds the resin film F. the both end surfaces of the resin film F wound by the winding shaft 2800 are arranged to be non-uniform.
The image forming part 2600 in the image forming apparatus of the fourth embodiment forms the latter image 1018 by being, shifted in the width direction of the resin film with respect to the former image 101A on the resin film F, as shown in
Then, the winding shaft 2800 in the image forming apparatus winds the resin film F without moving in the depth direction of the device.
Due to this, in the resin film F wound by the winding shaft 2800, the high image density portion 104 (see
As explained above, the image forming apparatus 1000 forms the latter image 101B by being shifted in the width direction of the resin film F with respect to the former image 101A on the resin film F. By this, the non-uniform arrangement of the width direction end surfaces of the wound resin film F is suppressed compared to a case where the resin film F on which an image has been formed is wound while shifting the resin film F in the width direction thereof.
The image forming part 2600 forms each image 101 while being shifted in the width direction of the resin film F on the resin film F. By this, the formation of the projection portion on the wound resin film F is suppressed compared to a case where images are irregularly shifted.
As explained above, in the case where an image is formed on the softer resin film F, the shifted amount when the softer resin film is used is set to be larger. By this, in the case where the softer resin film F is used, an overlapping margin of the high image density portion 104 in the shaft direction in the resin film F wound by the winding shaft 2800 becomes small than the case where a relatively hard resin film is used. Thus, a projection height of the projection portion formed when the softer resin film F is used becomes small, a strain of the resin film F generated from the projection portion is suppressed. It is considered that the largest shifted amount when using the softest resin film F among the all kinds of the resin films F is applied, but in the case where the shifted amount is large, a problem is caused during a slit process or the like, which is a post-processing, in some cases.
By this, with respect to a resin film F in which the shifted amount may be small, it is preferable that the shifted amount is not set to large.
As explained above, the image forming part 2600 can shift the latter image 101B in the width direction of the resin film F with respect to the former image 101A by shifting a position of an electrostatic latent image formed on the image support member 3600 by the exposure device 4200. Thus, the latter image 101B can be shifted with respect to the former image 101A with a more simple construction compared to the case of transferring the resin film F while being shifted in the width direction of the resin film F without shifting the position of the electrostatic latent image firmed on the image support member 3600.
The fourth embodiment of the present invention has been explained in detail, but the present invention is not limited thereto. It is apparent to a person skilled in the art that various modifications can be available without exceeding the range of the present invention. For example, in the fourth embodiment, the resin film F is made from polyethylene terephthalate, but the resin film F may be made from polypropylene, polystyrene, or the like.
In the fourth embodiment, a recording medium is the resin film F, but the recording medium may be paper or the like.
In the fourth embodiment, an image is formed on the resin film F by an electrographic method, but an inkjet method, a gravure method or the like may be available to form an image.
In the fourth embodiment, as one example, all images 101 are the same, but the images 101 may be different.
In the fourth embodiment, the image forming part 2600 forms each image 101 on the resin film F by being shifted in the width direction of the resin film F in a wavy form, but each image 101 may not be shifted in a wavy form.
In the fourth embodiment, the image forming parts shifts the latter image 101B in the width direction of the resin film F with respect to the former image 101A by shifting the position of the electrostatic latent image formed on the image support member 3600 by the exposure device 4200. However, for example, in a ease where only one image forming part 26 is provided, the latter image 101B may be shifted in the width direction of the resin film F with respect to the former image 101A by transferring the resin film F in a wavy form.
In the fourth embodiment, in the case where an image is formed on a softer resin film F, the shifted amount when using the softer resin film F is set to be larger than the case of using a relatively hard resin film F. However, resin films may be stepwise classified in a predetermined range based on softness of resin films F to determine the shifted amount depending on the classification.
The foregoing description of the exemplary embodiments of the present invention has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and there equivalents.
Number | Date | Country | Kind |
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2015-153360 | Aug 2015 | JP | national |
2015-153361 | Aug 2015 | JP | national |
2015-160102 | Aug 2015 | JP | national |