JP2008286865A - Image forming apparatus and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To apply image forming processing to normal label paper not containing special components in the form that the label paper is not curled. <P>SOLUTION: A laser machining system, as a cut forming means forming cuts on an outer surface of a releasing layer of the label paper, is driven and controlled linked with an image forming action forming an image on the label part of the label paper. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for preventing or eliminating curling of label paper as a sheet-like recording medium.

  Conventionally, an image forming apparatus forms an image on a label portion of a label sheet having a label portion and a release layer. In this case, since the expansion ratio is different between the label portion and the release layer, the label paper curls under a high temperature and high humidity environment, causing problems such as image defects and paper jams. In particular, in an electrophotographic image forming apparatus, by performing heat fixing, label paper may curl even if the natural environment is not high temperature and high humidity, and paper jam may occur in the conveyance path after fixing processing.

  In order to cope with this problem, the user has been informed by describing the label paper usage conditions and storage conditions on the surface of the package so that image defects and paper jams do not occur.

Further, a device has been devised in which metal powder is applied to the label paper so that the label paper itself is difficult to curl (see Patent Document 1).
JP 2004-271679 A

  However, the label paper according to Patent Document 1 is special, and cannot cope with the case where an image is formed on a normal label paper that is generally commercially available.

  Further, even if the user is notified of the use conditions and storage conditions of the label paper, the user does not always strictly observe these conditions, and it has not been possible to reliably prevent the occurrence of image defects and paper jams. Furthermore, it is inconvenient for the user to restrict the use of the label paper and to pay attention to the storage of the label paper.

  The present invention has been made under such a background, and an object of the present invention is to enable image forming processing to be performed in a form in which the label paper does not curl with respect to ordinary label paper that does not contain a special component. There is to do.

  In order to achieve the above object, the present invention provides an image forming apparatus for forming an image on a sheet-like recording medium, wherein the label paper as the sheet-like recording medium having a label portion and a release layer is It has a notch forming means for forming a cut in the outer surface of the release layer, and a control means for driving the notch forming means to form a cut in the outer surface of the release layer.

  According to the present invention, by forming a cut in the outer surface of the release layer of the label paper, image processing is performed on the normal label paper that does not contain a special component in a form in which the label paper does not curl. Is possible.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

  As shown in FIG. 1, the image forming apparatus 100 includes an image reading apparatus 101 and an image forming apparatus main body 102. The image reading apparatus 101 includes a document feeding device, and automatically feeds a document to be scanned to a document reading position. The image reading apparatus 101 reads an image of a fed document. The image forming apparatus main body 102 reads the document image by controlling the printer engine unit 104 with the controller 103, and forms an image on the sheet paper based on the document image.

  In the printer engine unit 104, exposure scanning on the photosensitive drum 105 is performed based on image data related to reading by an exposure device (not shown). By this exposure scanning, an electrostatic latent image reflecting the original image is formed on the photosensitive drum 105. This electrostatic latent image is developed as a toner image by the developing device 106. The toner image on the photosensitive drum 105 is transferred onto the sheet paper by the transfer unit 107. The toner image transferred to the sheet paper is fixed on the sheet paper by the fixing device 108. As described above, the fixing device 108 performs fixing processing by heating using the heating roller 108a and the pressure roller 108b. Thereafter, the sheet paper is sent to the outside of the apparatus or to a transport path 109 for refeeding.

  Sheet paper for image formation (including label paper) is supplied from a manual feed tray (not shown) serving as a sheet storage unit or paper cassettes 110 and 111. That is, the sheet paper is stored in a stacked state in the paper cassettes 110 and 111. When image forming processing is performed using the sheet paper in the paper cassettes 110 and 111, the sheet paper in the paper cassettes 110 and 111 is picked up by the pickup rollers 112 and 113.

  The picked-up sheet paper is separated into one sheet unit by a pair of separation rollers 114 and 115. The separated sheet paper is conveyed one by one to the position of the registration roller pair 117 by the conveyance roller pair 116. Then, after the skew is corrected by the registration roller pair 117, the sheet paper is conveyed to the transfer position in synchronization with the rotation of the photosensitive drum 105.

  By the way, when an image is formed on label paper, the label paper may curl. An image cannot be formed at all on the curled label paper, or even if an image can be formed, the formed image is distorted from the original image. Therefore, in order to prevent the curling of the label paper, the image forming apparatus 100 is provided with a laser processing device 118 for forming a cut and a temperature / humidity sensor 210 for detecting temperature / humidity in the vicinity of, for example, the upper portion of the paper cassette 110. is doing.

Next, curling of label paper and notches for preventing the curling will be described with reference to FIGS.
As shown in FIGS. 2A and 2B, the sheet-like label paper P has a label portion P1 and a release layer P2, respectively. Also, one label R is formed on the label portion P1 of the label paper P in FIG. Also, four labels R1 to R4 are formed on the label portion P1 of the label paper P in FIG. These labels R, R1 to R4 are formed for entering arbitrary characters, symbols and the like. On the labels R and R1 to R4, not only can arbitrary characters, symbols, etc. be handwritten, but also printing can be performed by the image forming apparatus.

  Note that the label portion P1 and the release layer P2 of the label paper P are detachably bonded by an adhesive material (not shown).

  Generally, paper or resin is used as the material for the label part P1 and the release layer P2, but different materials are used for the label part P1 and the release layer P2 due to differences in application and function.

  That is, the release layer P2 emphasizes the cost in consideration of the release performance and disposal after use, and the label portion P1 selects the material with an emphasis on vividness of printing, adhesive strength, strength that does not deteriorate over time, and the like. Has been.

  Thus, the material of the label paper P is different between the label portion P1 and the release layer P2. For this reason, when the label paper P thermally expands at high temperature or expands by absorbing moisture under high humidity, the amount of expansion differs between the label portion P1 and the release layer P2. In general, the release layer P2 made of an inexpensive material has a larger expansion amount than the label portion P1, and therefore the label paper P is curled in a form as shown in FIG.

  In addition, when an image is formed on the labels R, R1 to R4 of the label paper P by the image forming apparatus, if the curling occurs before the toner image is transferred to the labels R, R1 to R4, printing such as blurring of the image is performed. It may lead to a decrease in quality.

  Further, even when the environment around the image forming apparatus is not high temperature and high humidity, the label paper P curls in the process of forming an image on the labels R, R1 to R4 of the label paper P by the image forming apparatus. There is also.

  That is, when an image is formed on the labels R and R1 to R4 of the label paper P by the image forming apparatus, the toner images transferred to the labels R and R1 to R4 are subjected to fixing processing by the fixing device. As shown in FIG. 4, this fixing device is generally configured to perform fixing processing by heating using a heating roller 108a and a pressure roller 108b. Due to the fixing process by heating, the label paper P is curled due to the difference in thermal expansion between the label portion P1 and the release layer P2.

  In this way, when the label paper P is curled, the label paper P may cause a paper jam such as being caught at a paper guide path (not shown) at the subsequent stage of the fixing device, for example, at the joint of the paper guide. is there.

  Therefore, in order to prevent curling of the label paper P, in the first embodiment, a cut (groove portion) C is formed on the outer surface of the release layer P2 in the form shown in FIG. 5, for example. Yes. The cut C shown in FIG. 5 corresponds to the curl form shown in FIG.

  As the depth of cut (groove depth) of the cut C, it is desirable to cut less than the thickness of the release layer P2, as shown in FIG. The reason is that if the release layer P2 is completely cut into a cut state, the release layer P2 may be broken when the label portion P1 is peeled off from the release layer P2. Since the release layer P2 is generally about 100 μm, the depth of cut is preferably about 20 to 80 μm, that is, about 20 to 80% of the thickness of the release layer P2.

  When such an incision C is formed on the outer surface of the release layer P2, even if the release layer P2 expands more than the label portion P1 due to high temperature, high humidity, etc., as shown by the solid line in FIG. The amount difference is absorbed by the cut C. For this reason, the balance of stress inside the label paper P is not lost, and curling of the label paper P can be prevented in advance.

  As shown in FIG. 3, the label paper P does not necessarily have a curled shape that curls as a whole in the lateral direction (the direction in which the label paper is transported) with the center at the center. That is, as shown in FIG. 8A, the label paper P may be curled in the vertical direction (direction perpendicular to the transport direction of the label paper).

  In this way, when it is previously known that a certain label paper P has a characteristic of curling in the horizontal direction and about half of the vertical direction, as shown in FIG. Cuts C may be formed only in the half of the P peeling layer P2 that curls. In this case, it is desirable to form the cut C in a direction perpendicular to the curling direction (see the arrow in FIG. 8A and the cut C in FIG. 8B for comparison).

  Further, as shown in FIG. 9A, the label paper P may be curled diagonally only at the corners. For the label paper P having such curl characteristics, as shown in FIG. 9B, diagonal direction is applied to the curled corner portion of the release layer P2 of the label paper P. A notch C may be formed.

  In this case, it is desirable to form the cuts C for preventing curling of the label paper P in a direction orthogonal to the direction in which the label paper P curls. Further, it is not necessary to form the cut C over the entire surface of the release layer P2 of the label paper P, and the cut C may be formed only at the curled portion.

  In addition, when the label paper P curls in a random direction depending on the region, or when the curl shape cannot be predicted, a lattice-shaped cut C may be formed. If the curling of the label paper P can be prevented, only one cut C may be formed. Further, the cutting amount may be changed according to the amount of curl. That is, the cut C in the portion curled greatly increases the cut amount, and the cut C in the portion curled small reduces the cut amount. Further, the number (density) of cuts may be changed according to the amount of curl. That is, a large number of cuts C with a narrow interval are formed in a portion that is largely curled, and a small number of cuts C with a large interval are formed in a portion that is curled small.

  Further, the cut C need not be linear. For example, a wavy line as shown in FIG. 10A and a zigzag notch C as shown in FIG. 10B may be formed in the release layer P2 of the label paper P. In the case of the cuts C of these wavy lines and zigzag lines, it is possible to balance the stress not only in a fixed direction but also in a plurality of directions, and curling in a plurality of directions can be prevented with a small number of cuts C. Become.

  The label paper P having the curl characteristics as described above is stored in the paper cassette 110 in such a manner that the release layer P2 is the upper surface in the image forming apparatus 100 of FIG. The part P1 is the upper surface. In other words, the release layer P2 and the laser processing device 118, which will be described later, of the laser processing device 118 are in a positional relationship so as to face each other, and it is possible to directly irradiate the release layer P2 with a laser beam for cutting. It has become.

  As shown in FIG. 11, the laser processing device 118 is configured in the same manner as an exposure device for forming an electrostatic latent image related to a read image on the photosensitive drum 105.

  That is, the laser processing device 118 includes a laser oscillation device 119, a polygon motor 121 for rotating the polygon mirror 120, an fθ lens 122, a reflection mirror 123, and a BD sensor 124. The laser processing device 118 is driven and controlled by the controller 103 (see FIGS. 1 and 12). By this drive control, the laser oscillation device 119 oscillates a laser beam. The energy of the laser beam is determined in consideration of the cut amount of the cut C formed on the label paper P.

  The laser beam oscillated from the laser oscillating device 119 is deflected while its reflection angle is continuously changed by the rotating polygon mirror 120. The deflected laser beam is subjected to correction of distortion by the fθ lens 122 and then irradiated to the label paper P through the reflection mirror 123. By this laser beam irradiation, a cut C for preventing or eliminating curling is formed on the label paper P. The timing for starting the operation of forming the cut C is determined based on the detection signal of the laser beam from the BD sensor 124. The BD sensor 124 is a sensor that detects that the laser beam oscillated from the laser oscillation device 119 is scanned at a predetermined position.

  The reflection mirror 123, which is a part of the optical system that guides the laser beam onto the label paper, is configured to change the angle in the vertical direction. Accordingly, the vertical angle of the reflecting mirror 123 is changed by the controller 103 and moved by the label paper feeding operation, so that FIGS. 5, 8B, 9B, 10A, An arbitrary notch C as shown in b) can be formed.

  In other words, the laser processing device 118 forms the cut C by controlling the laser oscillation device 119 with the same control as the case where the electrostatic latent image is formed on the photosensitive drum 105 by the exposure device in the image forming device 100. . The reason for changing the angle of the reflecting mirror 123 is to allow a cut to be partially formed before the label sheet feeding operation (in a stopped state). Even when the label paper is moving, the angle of the reflecting mirror 123 can be changed to repeatedly irradiate the same position on the label paper with the laser beam, and a cut is formed even if the intensity of the laser beam is reduced. can do.

  Next, the configuration of the controller 103 will be described with reference to FIG. The controller 103 has a CPU circuit unit 201. The CPU circuit unit 201 includes a CPU (not shown), a ROM 202, and a RAM 203.

  The ROM 202 stores a control program for controlling various image forming operations by the image forming apparatus 100. This control program includes one corresponding to the flowchart of FIG. The ROM 202 stores data for determining various forms of the cut C described with reference to FIGS. 2 to 10 in a table format. The RAM 203 is used as a work area when performing arithmetic processing by the CPU.

  Connected to the CPU circuit unit 201 are a document feeding device control unit 204, an image reader control unit 205, an image signal control unit 206, a printer control unit 207, an operation unit 208, a laser processing device control unit 209, and a temperature / humidity sensor 210. Has been. The CPU circuit unit 201 executes a series of image forming processes by appropriately controlling the devices related to these connections.

  The document feeder control unit 204 controls a document transport operation by the document feeder. The image reader control unit 205 drives and controls a scanner unit and an image sensor (not shown) of the image reading apparatus 101, and transfers an analog image signal output from the image sensor to the image signal control unit 206. The image signal control unit 206 converts the analog image signal from the image sensor into a digital signal, performs various image processing, converts the digital signal into a video signal, and outputs the video signal to the printer control unit 207.

  The printer control unit 207 performs the above-described exposure scanning based on the input video signal, and controls a series of image forming processes such as subsequent development processing, transfer processing, and fixing processing. The printer control unit 207 also controls sheet paper conveyance processing and paper discharge processing. The operation unit 208 has a plurality of keys for setting various functions related to image formation. The operation unit 208 is also used when inputting the type of label paper P and the number of labels (number of faces) on the label paper P.

  The laser processing device control unit 209 drives the laser processing device 118 under the control of the CPU circuit unit 201 to form a cut C for preventing or eliminating curl in the release layer P2 of the label paper P. The temperature / humidity sensor 210 detects temperature / humidity as one element for predicting the form of curl generated on the label paper P.

  Next, an image forming process (including a cut forming process) performed by the image forming apparatus 100 will be described with reference to the flowchart of FIG. Note that the flowchart in FIG. 13 corresponds to the case where the image forming operation of the image forming apparatus 100 is slow.

  The controller 103 accepts the label paper P type, the number of faces, etc., and the label printing instruction input from the operation unit 208 by the user (step S1). When the label printing is instructed, the controller 103 acquires information on the temperature and humidity detected by the temperature and humidity sensor 210 (step S2).

  Next, the controller 103 makes a cut C such as the width, interval, direction, type, depth (cut amount) of the line of the cut C based on the information on the type, number of sides, temperature and humidity of the label paper P described above. Is determined (step S3). In this case, the controller 103 determines the form of the cut C by referring to the data on the aforementioned table stored in the ROM 202. Next, the controller 103 controls the document feeding control unit 204, the image reader control unit 205, the image signal control unit 206, and the printer control unit 207 to start a series of image form processing starting from document image reading processing ( Step S4).

  And the controller 103 controls the laser processing apparatus control part 209, and starts the formation process of the cut C with respect to the peeling layer P2 of the label paper P (step S5). Next, the controller 103 controls the printer control unit 207 to start a paper feeding operation for feeding the label paper P to the transfer position (step S6). Then, the controller 103 discharges the label paper P that has been subjected to the toner image transfer process and the fixing process to a stack tray (not shown) (step S7), and ends the process.

  As described above, the laser processing device 118 that forms the cut C is provided on the upper portion of the paper cassette 110. Therefore, in the process of step S5, the cut C is formed in the release layer P2 of the label paper P before the image is formed on the label paper P.

  In other words, an image can be formed on the labels R, R1 to R4 of the flat label paper P where no curling occurs, and the print quality is not deteriorated such that the image is blurred. Even if the label paper P is heated during the fixing process, the curled paper P is not curled by the overheating. Accordingly, the label paper P is not caught by the paper discharge unit, and the label paper P can be smoothly discharged outside the apparatus main body 102. Furthermore, the discharged label paper P can be smoothly stacked on a stack tray (not shown), and the subsequent label peeling work is facilitated.

  The laser processing device 118 for forming the cuts is not based on the beam deflection method using the polygon mirror 120 as shown in FIG. 11, but can also be a method in which the laser oscillation device is mounted on the XY stage. In this case, the controller 103 drives and controls the XY stage so as to change the relative positional relationship between the label paper P and the laser oscillation unit, and FIG. 5, FIG. 8B, FIG. Cuts C in an arbitrary direction as shown in 10 (a) and 10 (b) are formed.

  Further, without using a dedicated laser processing device for forming cuts, an existing exposure device generally mounted in an image forming device is used to prevent or eliminate curling on the release layer P2 of the label paper P. It is also conceivable to form the cuts C.

  In this case, a configuration is required in which the optical path for irradiating the photosensitive member with the laser beam is switched to the sheet conveyance path. Furthermore, if a mode for performing only the process of forming the cut C is provided, and the process of forming the cut C is performed without being linked to the actual image forming process for the label paper P, all the image forming apparatuses including the exposure apparatus can perform the process. It is possible to perform the formation process of the cut C. However, by devising the configuration of the image forming apparatus, it is possible to perform the formation process of the cut C in conjunction with the actual image forming process for the label paper P using an existing exposure apparatus.

[Second Embodiment]
A label paper P, which does not generate curl under a natural environment and generates curl exclusively by heat treatment during fixing processing, is generally commercially available. Therefore, in the second embodiment, as shown in FIG. 14, the cut forming device 302 is arranged at a position between the photosensitive drum 301 and the fixing device 305 in the paper conveyance path of the image forming device 300. .

  This incision forming apparatus 302 has a cutting blade 302a for making the cutting C and a receiving portion 302b for receiving a pressing force by the cutting blade 302a. In addition, in order to be able to form a notch | incision in arbitrary directions as shown in FIG.5, FIG.8 (b), FIG.9 (b), FIG.10 (a), (b), the cutting blade 302a and a receiving part 302a can be integrally rotated in a horizontal plane.

  In the present embodiment, it is assumed that there is only one cutting blade 302a. However, in order to be able to form a plurality of line-shaped cuts such as straight lines, wavy lines, zigzag lines, etc., a plurality of cutting blades having different blade shapes and a plurality of corresponding receiving portions are provided, and these cutting blades are selectively used. It is also possible to drive.

  At the position of the incision forming device 302, the label paper P is conveyed from the right to the left in FIG. 14 with the label portion P1 on the upper surface and the release layer P2 on the lower surface. Therefore, the incision forming device 302 is arranged so that the incision blade 302a is located on the lower side of the conveyance path and the receiving portion 302b is located on the upper side of the conveyance path in order to form a cut in the release layer P2.

  Then, the cutting blade 302a is driven in the upward direction (direction perpendicular to the sheet surface) by a driving unit (not shown) and pressed against the peeling layer P2 of the label paper P, thereby forming the cutting C in the peeling layer P2. can do. In this case, the cutting amount can be controlled by controlling the upward driving amount of the cutting blade 302a.

  A sheet sensor 303 is provided on the upstream side of the photosensitive drum 301. In the present embodiment, it is assumed that only one sheet sensor 303 is provided. Then, the edge of the label paper P conveyed for image formation is accurately detected by the sheet sensor 303, and the conveyance operation of the label paper P and the driving operation of the cutting blade 302a are synchronized, thereby releasing the release layer. A cut C can be formed at a desired position of P2.

  Thus, by forming the cut C in the release layer P2 of the label paper P before the fixing process, even if the label paper P is heated at a high temperature by the fixing device 305, the heating causes curling. This can be prevented in advance.

  As shown in FIG. 14, in order to detect the curled state of the label paper P, it is possible to provide a large number of distance sensors 304 that are simultaneously opposed to a large number of areas of the label paper P. .

  In this case, a minute curl shape that does not affect the image quality is detected using a number of distance sensors 304, and a large curl shape of the label paper P by heating in the fixing device 305 is detected based on the curl shape. Can be predicted. Then, by forming the cut C having a shape corresponding to the predicted curl shape on the label paper P by the cut forming device 302, it is possible to reliably prevent the curl from occurring.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention. It is a figure which shows the structure of label paper. It is a figure which shows the curl form of label paper. It is a figure which shows the curl state by the fixing process of label paper. It is a figure which shows the formation state of a notch (corresponding to FIG. 2). It is a figure which shows the form of a cut. It is a figure for demonstrating the curl prevention effect by cutting. It is a figure which shows the curl form of label paper, and the corresponding notch | incision. It is a figure which shows the other curl form of label paper, and the cut corresponding to it. It is a figure which shows the shape of the line of a notch | incision. It is a figure which shows schematic structure of the laser processing apparatus as a notch formation means. It is a block diagram which shows schematic structure of a controller. It is a flowchart which shows the image formation process containing a notch formation process. It is a figure which shows the other structural example of a notch formation means (2nd Embodiment).

Explanation of symbols

C ... cut P ... label paper P1 ... label part P2 ... peeling layers R, R1 to R4 ... label 100 ... image forming apparatus 103 ... controller 118 ... laser processing apparatus 209 ... laser processing apparatus control part 201 ... CPU circuit part 210 ... warm Humidity sensor 302 ... cut forming device 302a ... cutting blade 302b ... receiving portion

Claims (10)

In an image forming apparatus for forming an image on a sheet-like recording medium,
For label paper as the sheet-like recording medium having a label portion and a release layer, a notch forming means for forming an incision on the outer surface of the release layer;
Control means for driving the cut forming means to form a cut on the outer surface of the release layer;
An image forming apparatus comprising:   The control means drives and controls the notch forming means so as to form a notch on the outer surface of the release layer of the label paper in conjunction with an image forming operation for forming an image on a label portion of the label paper. The image forming apparatus according to claim 1.   The image forming apparatus according to claim 1, wherein the notch forming unit is provided in the vicinity of a storage unit that stores the label paper.   The image forming apparatus according to claim 1, wherein the cut forming unit forms a cut on an outer surface of the release layer by irradiating the release layer with a laser beam.   The image forming apparatus according to claim 4, wherein the notch forming unit forms a notch line on an outer surface of the release layer by deflecting a laser beam.   The incision forming means forms an incision line on the outer surface of the release layer by changing a relative positional relationship between an optical system for guiding the laser beam onto the label paper and the label paper. The image forming apparatus according to claim 4.   The image forming apparatus according to claim 1, wherein the cut forming unit forms a cut on an outer surface of the release layer by pressing a cutting blade against the release layer.   The image forming apparatus according to claim 1, wherein the control unit drives and controls the cut forming unit so as to form a cut having a cut amount smaller than a thickness of the release layer.   A temperature / humidity sensor for detecting temperature and humidity is provided, and the control means determines the form of the cut formed in the release layer in consideration of the temperature / humidity detected by the temperature / humidity sensor. Item 2. The image forming apparatus according to Item 1. A control method for an image forming apparatus equipped with a notch forming means for forming a notch on an outer surface of a release layer of a label paper as a sheet-like recording medium,
An image forming apparatus that drives and controls the notch forming unit so as to form a notch on an outer surface of a release layer of the label paper in conjunction with an image forming operation for forming an image on a label portion of the label paper. Control method.

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