Sheet feeder and image forming system

Abstract

To enable placing and feeding of multiple sheets that do not require an air blowing operation even when an air blowing device has failed.SOLUTION: A sheet feeder comprises: an air separating unit for performing blowing action to separate sheets by blowing air to side surfaces of a plurality of sheets placed on a sheet placing portion; a control unit that determines whether or not the blowing action by the air separating unit is necessary in accordance with the kind of the sheet set by a setting unit; and a failure detection unit that detects a failure of the air separating unit. When a failure of the air separating unit is detected by the failure detection unit, the control unit prohibits setting of sheets that are determined to require a blowing action by the air separating unit, and limits setting to sheets that are determined not to require a blowing action by the air separating unit.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a sheet feeding device and an image forming system that perform a blowing operation to blow air to separate sheets. [Background technology]

[0002] Image forming devices such as copiers, facsimiles, and printers, and image forming systems equipped with image forming devices, are equipped with sheet feeding devices such as a feeding cassette, a feeding deck, and a manual feeding section in which sheets to be supplied to an image forming section where an image is formed are set.

[0003] In recent years, there has been an increasing demand for forming images on various types of sheets, and sheets with smooth surfaces, such as coated paper, are sometimes used as recording materials. When a stack of sheets with such smooth surfaces is set in a sheet feeding device, the sheets may adhere closely to each other, making it difficult to feed the sheets. For this reason, a configuration has been proposed in which air is blown onto the stack of sheets to lift them up and separate them (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 4-23747 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a configuration in which air is blown onto a stack of sheets to separate them while the sheets are being fed as in Patent Document 1, if the device that blows the air breaks down, the sheets cannot be separated. If the sheets are fed in a state in which the sheets cannot be separated, multiple sheets may be fed at the same time, which may cause a paper jam.

[0006] As a countermeasure, it is conceivable to prohibit the sheet feeding from the sheet feeding device in which the air blowing device has broken down. However, in this case, sheet feeding under conditions where the air blowing operation is not required would also be prohibited. This would result in a significant decrease in usability.

[0007] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a sheet feeding device that can feed a plurality of sheets that do not require air blowing even if the air blowing device breaks down. [Means for solving the problem]

[0008] A typical configuration of the present invention includes a sheet placing section on which multiple sheets can be placed, a sheet feeding section which feeds the sheets placed on the sheet placing section, an air handling section which performs a blowing operation of blowing air onto the sides of the multiple sheets placed on the sheet placing section to handle the sheets, a setting section which sets the type of sheet, a memory section which stores the type of sheet set by the setting section, a control section which determines whether or not the blowing operation by the air handling section is necessary depending on the type of sheet set by the setting section, and a failure detection section which detects a failure of the air handling section, and the control section is characterized in that when the failure detection section detects a failure of the air handling section, the control section prohibits the setting of a sheet for which it is determined that the blowing operation by the air handling section is necessary, and limits the setting to a sheet for which it is determined that the blowing operation by the air handling section is not necessary. Effect of the Invention

[0009] According to the present invention, even if the air blowing device breaks down, sheets that do not require the air blowing operation can be fed even if multiple sheets are placed. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of an image forming system. [Diagram 2] FIG. 2 is a block diagram showing a control system of the image forming system. [Diagram 3] FIG. 2 is a schematic diagram illustrating a configuration of a manual feeding section. [Figure 4] 13 is a schematic diagram showing a state in which an air blowing operation is performed in the manual feed section; FIG. [Diagram 5] 5 is a flowchart showing a sheet feeding control according to the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating an operation unit in the image forming apparatus. [Figure 7] 5A and 5B are diagrams showing setting screens displayed on a display unit of an operation unit. [Figure 8] 5A and 5B are diagrams showing setting screens displayed on a display unit of an operation unit. [Figure 9] 6 is a flowchart showing a method for setting a sheet type and an air blowing execution flag according to the first embodiment. [Figure 10] 11 is a table showing the relationship between the type of sheet and whether or not air blowing is required. [Figure 11] 4 is a flowchart showing a reporting method according to the first embodiment. [Figure 12] FIG. 4 is an explanatory diagram of a notification message according to the first embodiment. [Figure 13] 10 is a flowchart showing a method for setting a sheet type and an air blowing execution flag according to a second embodiment. [Figure 14] FIG. 11 is an explanatory diagram of a first notification message according to the second embodiment. [Figure 15] 10 is a flowchart showing a reporting method according to a second embodiment. [Figure 16] FIG. 11 is an explanatory diagram of a second notification message according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative positions of the components described in the following embodiments may be changed as appropriate depending on the configuration of the device to which the present invention is applied and various conditions, and are not intended to limit the scope of the present invention to these alone.

[0012] Example 1 First, an image forming system 600 including an image forming apparatus 201 and a manual feed unit 235 as a sheet feeder connected thereto will be described with reference to Fig. 1. Fig. 1 is a diagram showing a schematic configuration of the image forming system according to the first embodiment.

[0013] [Outline of image forming system] 1, the image forming system 600 includes an image forming apparatus 201, a manual feed section 235, and a feed deck 500 connected to the image forming apparatus 201. The feed deck 500 is connected to the right side of the image forming apparatus 201 in FIG. 1, and is configured to be able to feed a sheet S to the image forming apparatus 201. In addition, the manual feed section 235 as a sheet feeder is also configured to be able to feed a sheet S to the image forming apparatus 201.

[0014] [General configuration of image forming device] As shown in Fig. 1, the image forming apparatus 201 has an image forming section 201B that forms an image on a sheet. The image forming section 201B is installed in an image forming apparatus main body 201A. The image reading device 202 is installed substantially horizontally above the image forming apparatus main body 201A. An ejection space V for ejecting sheets is formed between the image reading device 202 and the image forming apparatus main body 201A. An operation section 700 configured with a touch panel or the like capable of displaying a screen is disposed above the image forming apparatus main body 201A.

[0015] The image forming section 201B, which is an image forming means, is of a four-drum full-color type. The image forming section 201B includes a laser scanner 210 and four process cartridges 211Y, 211M, 211C, and 211K that form toner images of four colors, yellow (Y), magenta (M), cyan (C), and black (K). Here, each process cartridge 211 includes a photosensitive drum 212, a charger 213 that is a charging means, and a developer 214 that is a developing means. In addition, the image forming section 201B includes an intermediate transfer unit 201C arranged above the process cartridge 211, and a fixing section 201E. In addition, a toner cartridge 215 is for supplying toner to the developer 214.

[0016] The intermediate transfer unit 201C includes an intermediate transfer belt 216 wound around a drive roller 216a and a tension roller 216b. A primary transfer roller 219 is provided on the inner side of the intermediate transfer belt 216, and contacts the intermediate transfer belt 216 at a position facing the photosensitive drum 212. The intermediate transfer belt 216 is rotated in the direction of the arrow by a drive roller 216a driven by a drive unit (not shown).

[0017] Then, the negative color toner images on the photosensitive drums are sequentially transferred onto the intermediate transfer belt 216 by the primary transfer roller 219. A secondary transfer roller 217 that transfers the color image formed on the intermediate transfer belt onto the sheet S is provided at a position facing the driving roller 216a of the intermediate transfer unit 201C. A secondary transfer section 201D is formed between the intermediate transfer belt 216 and the secondary transfer roller 217. Furthermore, a fixing section 201E having a pressure roller 220a and a heating roller 220b is provided above the secondary transfer roller 217. A first discharge roller pair 225a, a second discharge roller pair 225b, and a double-sided reversing section 201F are provided at the upper left of the fixing section 201E. The double-sided reversing section 201F is provided with a reversing roller pair 222 that can rotate forward and backward, a re-conveying path R that conveys the sheet with an image formed on one side to the image forming section 201B again, and the like.

[0018] A sheet feeding unit 230 that feeds the set sheets S to the image forming section 201B is provided at the bottom of the image forming apparatus main body 201A. The sheet feeding unit 230 includes a feeding cassette 1 that stores sheets, and a sheet feeding section 506 that feeds the sheets S stored in the feeding cassette 1. The sheet feeding section 506 includes a pickup roller 2 as a sheet feeding means that feeds the sheets, and a feed roller 3 and a retard roller 4 as a separation means that separates the sheets S fed by the pickup roller 2.

[0019] Further, a manual feed section 235 that sends out a set sheet S to the image forming section 201B is provided on the right side surface of the image forming apparatus main body 201A in FIG. 1. The manual feed section 235 includes a manual tray 6 on which a sheet is placed, and a sheet feed section 506 that feeds the sheet S placed on the manual tray 6. The sheet feed section 506 includes a sheet feeding means and a separation means, similar to the sheet feeding unit 230. The manual feed section 235 will be described in detail later.

[0020] Further, on the right side surface of the image forming apparatus main body 201A in FIG. 1, below the manual feed section 235, there is provided a feed deck 500 for feeding the set sheet S to the image forming section 201B.

[0021] Next, the image forming operation of the image forming apparatus 201 will be described. First, when image information of an original is read by the image reading device 202, this image information is image-processed, converted into an electric signal, and transmitted to the laser scanner 210 of the image forming section 201B. In the image forming section 201B, the surface of the photosensitive drum 212, the surface of which is uniformly charged to a predetermined polarity and potential by the charger 213, is sequentially exposed to laser light. As a result, electrostatic latent images of yellow, magenta, cyan, and black are sequentially formed on the photosensitive drum of each process cartridge 211, respectively.

[0022] Thereafter, the electrostatic latent images are developed and visualized with toner of each color, and the toner images of each color on each photosensitive drum are transferred in order onto the intermediate transfer belt 216 in a superimposed manner by a primary transfer bias applied to the primary transfer roller 219. As a result, a toner image is formed on the intermediate transfer belt 216.

[0023] On the other hand, the sheet S fed by the feed roller 3 of the sheet feeding unit 230 is conveyed to a pair of registration rollers (hereinafter referred to as the registration roller pair) 240 consisting of a drive roller and a driven roller. At this time, the driving of the registration roller pair 240 is stopped, and the leading edge of the sheet S is abutted against the registration roller pair 240. As a result, the leading edge of the sheet S is made to follow the registration roller pair 240. Thereafter, as the sheet S continues to be conveyed by the feed roller 3, a flexure (loop) is formed in the sheet S, and when a predetermined loop amount is reached, the registration roller pair 240 is driven. As a result, the skew of the sheet S is corrected by the registration roller pair 240, and the sheet S with the skew corrected is conveyed to the secondary transfer portion 201D by the registration roller pair 240. Subsequently, in the secondary transfer portion 201D, the toner images are transferred collectively onto the sheet S by a secondary transfer bias applied to the secondary transfer roller 217. The sheet S onto which the toner image has been transferred is then conveyed to a fixing section 201E, where the toner of each color is melted and mixed by heat and pressure, and is fixed onto the sheet S as a color image.

[0024] Thereafter, the sheet S on which the image has been fixed is discharged to the discharge space V by a first discharge roller pair 225a and a second discharge roller pair 225b provided downstream of the fixing section 201E, and is stacked on a stacking section 223 formed on the bottom surface of the discharge space V. When images are formed on both sides of the sheet S, after the images are fixed, the sheet S is transported to a re-conveying path R by a reversing roller pair 222, and is transported again to the image forming section 201B.

[0025] [Manual feed section configuration] Next, the manual feed unit 235 as a sheet feeding device will be described in detail with reference to Fig. 1 and Fig. 3. Fig. 3 is a schematic diagram showing the configuration of the manual feed unit 235 according to the first embodiment.

[0026] 1 and 3, the manual feed section 235 includes a manual feed tray 6 as a sheet placement section on which a plurality of sheets can be placed, and a sheet feed section 506 that feeds the sheets placed on the manual feed tray 6. The sheet feed section 506 also includes a pickup roller 501 as a sheet feed means that comes into contact with the top sheet of a sheet stack consisting of a plurality of sheets S and feeds the top sheet. The sheet feed section 506 also includes a feed roller 502 and a retard roller 503 as a separation means that separates the sheet S fed by the pickup roller 501.

[0027] Further, in the manual feed section 235, downstream of the feed roller 502 in the sheet feed direction, there is disposed a pull-out roller 504 which pulls out the sheet S from the feed roller 502 and feeds it to the image forming apparatus 201. Further, downstream of the sheet feed section 506 in the sheet feed direction, there is disposed a feed sensor 505 as a sheet detection section. The feed sensor 505 is disposed between the feed roller 502 and the pull-out roller 504 in the sheet feed direction, and detects the passage of the sheet S by outputting a signal depending on the presence or absence of the sheet S.

[0028] 3, the manual feed tray 6 includes a manual feed tray base 515 and a lifter plate 514 as a sheet support portion that supports a sheet stack consisting of a plurality of sheets S. The lifter plate 514 is provided with a sheet detection sensor 401 that detects the presence or absence of a sheet. The sheet detection sensor 401 detects whether or not the sheet S (or the sheet stack) is supported by the lifter plate 514 by outputting a signal depending on the presence or absence of the sheet S. The height position of the lifter plate 514 is controlled by a lifting mechanism (not shown) depending on the amount of the sheets S loaded.

[0029] 3, the manual feed tray 6 is provided with side end regulating plates 511, 512 as regulating members. The side end regulating plates 511, 512 are provided movably in a width direction perpendicular to the feeding direction of the sheet S, and regulate the positions of both ends (side ends of the sheet) in the width direction perpendicular to the feeding direction of the sheet S set on the lifter plate 514. The side end regulating plates 511, 512 are disposed opposite each other in the width direction of the sheet S.

[0030] The side end regulating plates 511 and 512 are provided with air blowing sections 511A and 512A as air handling sections, respectively. The air blowing section 511A of the side end regulating plate 511 on one side in the width direction has a fan 511b driven by a fan motor 511M (see FIG. 2) and a nozzle 511a that guides the air blown from the fan 511b and blows it from the side of the sheet stack. Similarly, the air blowing section 512A of the side end regulating plate 512 on the other side in the width direction has a fan 512b driven by a fan motor 512M (see FIG. 2) and a nozzle 512a that guides the air blown from the fan 512b and blows it from the side of the sheet stack. In addition, the side end regulating plates 511 and 512 are provided with floating suppression plates 511c and 512c near the nozzles 511a and 512a. The lift suppression plates 511c and 512c prevent the sheet S, to which air is blown, from lifting up and climbing over the side end regulating plates 511 and 512.

[0031] [Configuration of the control system of the image forming system] Next, the configuration of a control system in the image forming system 600 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing the control system of the image forming system according to the first embodiment.

[0032] A control unit 100 according to this embodiment is provided in, for example, an image forming apparatus 201. The control unit 100 includes a CPU 101, a ROM 102 that stores programs for controlling each unit, and a RAM 103 that temporarily stores data.

[0033] ROM 102 (storage section) stores various programs related to the control of image forming apparatus 201, various image data, tables (see FIG. 10) described later, and the like. CPU 101 performs various arithmetic processing based on the control programs stored in ROM 102, and the like. RAM 103 (storage section) temporarily stores data such as the set sheet type and air blowing execution flag described later. In other words, CPU 101 uses RAM 103 as a working area based on the control programs stored in ROM 102, and controls each section connected to control section 100 to perform various operations.

[0034] The control unit 100 is a control means that controls the image forming apparatus 201, the feeding deck 500, and the manual feeding unit 235. The control unit 100 is connected to a host device 900 and an operation unit 700, and performs signal processing and sequence control for various process devices while exchanging information with them. The host device 900 is an external device such as a personal computer, an image scanner, or a facsimile.

[0035] The control unit 100 is connected to the fan control unit 402, the feed motor 520 that drives the pickup roller 501, the torque measurement unit 520a that measures the motor torque of the feed motor 520, the feed sensor 505, the conveying motor 521, the sheet detection sensor 401, and the like. The torque measurement unit 520a measures the motor torque of the feed motor 520, but may be, for example, a current sensor that detects the current value flowing through the feed motor 520 or a torque sensor that detects the torque generated in the pickup roller 501. In other words, the specific configuration of the torque measurement unit 520a may be anything that can measure the motor torque of the feed motor 520. The fan control unit 402 controls the rotation of the fans 511b and 512b driven by the fan motors 511M and 512M, and simultaneously detects failures of the fans 511b and 512b. In other words, the fan control unit 402 is a failure detection unit that detects failures of the air blowing units 511A and 512A. The fan control unit 402 counts the number of rotations of each of the fans 511b, 512b, and is able to determine whether or not each of the fans 511b, 512b has failed depending on whether or not the number of rotations reaches an intended number.

[0036] [Air blowing action] Next, the state of the sheets S when air is blown from the side of the sheet stack by the air blowing units 511A and 512A will be described with reference to Fig. 4. Fig. 4 is a schematic diagram showing a state in which the manual feed unit 235 according to the first embodiment performs an air blowing operation (hereinafter, referred to as "air blowing operation").

[0037] As shown in Fig. 4, air is blown from fan 511b of air blowing section 511A on one side in the width direction toward one side of the sheet stack as indicated by arrow A1. Similarly, air is blown from fan 512b of air blowing section 512A on the other side in the width direction toward the other side of the sheet stack as indicated by arrow A2. Then, several to several tens of sheets S above the sheet stack are separated and floated, while the floating suppression plates 511c, 512c suppress the floating of the sheets S. This reduces the adhesion force between the sheets S separated by the air, and it becomes possible to feed the sheets S by the pickup roller 501 even if the sheets S have a smooth surface, such as coated paper.

[0038] [Sheet feeding control according to the first embodiment] Next, the sheet feeding control according to the first embodiment will be described with reference to Fig. 5. Fig. 5 is a flowchart showing the sheet feeding control according to the first embodiment.

[0039] The control unit 100 starts a sheet feeding control (mode) to feed, for example, 15 sheets as the number of sheets required for printing by the image forming apparatus 201 (S1).

[0040] Then, first, in order to determine whether or not an air blowing operation is required, an air blowing execution flag is checked (S10). The air blowing execution flag will be described later.

[0041] If the air blowing execution flag is ON (Yes in S10), the air blowing operation is necessary, so the process proceeds to S2 and the air blowing operation is started. On the other hand, if the air blowing execution flag is OFF (No in S10), the air blowing operation is not necessary, so the process proceeds to S5 and the paper feed operation is started without the air blowing operation.

[0042] If the air blowing operation is necessary (Yes in S10), the fan motors 511M, 512M (see FIG. 2) of the air blowing units 511A, 512A are driven in S2 to start the air blowing operation of blowing air to the side of the sheet stack. As a result, several to several tens of sheets S above the sheet stack are separated and floated, while the floating suppression plates 511c, 512c suppress the floating of the sheets S (see FIG. 4), and the adhesion force between the sheets is reduced. At this time, since the fan motors 511M, 512M start rotating from a stopped state, a predetermined time, such as 10 seconds, is set in advance as the time until the desired number of rotations (rotation speed) is reached and the time until the floating of the sheets S becomes stable. Then, the air blowing operation is performed until the predetermined time has elapsed (No in S3), and when the predetermined time has elapsed (Yes in S3), the air blowing operation is stopped (S4). That is, the drive of the fan motors 511M, 512M is turned off. As a result, the sheets S, which were in a floated state, attempt to return to the state of the sheet stack before floating as the air between the sheets is released, but since the adhesion between the sheets remains reduced until the sheets return to the state of the sheet stack, the feeding operation of the sheets S is started at S5.

[0043] On the other hand, if the air blowing operation is not required (No in S10), in S5 the feeding operation is started without performing the air blowing operation.

[0044] The start of the feeding operation (S5) refers to the feeding of the sheet S by the pickup roller 501 being driven to rotate by the feeding motor 520 while in contact with the topmost sheet S in the sheet stack. Thereafter, a series of feeding operations are performed, such as separating the overlapped sheets S in a separation unit consisting of a feed roller 502 and a retard roller 503, and detecting the passage of the sheets S by a feeding sensor 505. Then, in this embodiment, the feeding operation is repeated until the feeding of the required number of sheets S, for example, 15 sheets S, is completed (No in S6), and when the feeding of the required number of sheets S is completed (Yes in S6), the sheet feeding control is terminated (S7).

[0045] [Method of Setting Sheet Information and Air Blowing Execution Flag According to the First Embodiment] Next, a method for setting sheet information such as the paper size, paper type, and basis weight of the sheet set in the manual feed tray 6, and a method for setting the air blowing execution flag will be described with reference to FIGS. 6 to 8(b), 9, and 10.

[0046] FIG. 6 is a diagram showing the operation unit 700 in the image forming apparatus of FIG. 1. FIG. 7(a) and FIG. 7(b) are diagrams showing a setting screen displayed on the display unit 720 of the operation unit 700, FIG. 7(a) is a diagram showing a setting screen for a paper feed tray, and FIG. 7(b) is a diagram showing a setting screen for a paper size. FIG. 8(a) and FIG. 8(b) are diagrams showing a setting screen displayed on the display unit 720 of the operation unit 700, FIG. 8(a) is a diagram showing a paper type selection screen, and FIG. 8(b) is a diagram showing a paper type selection screen including a button for prohibiting the setting. FIG. 9 is a flowchart showing a method for setting a paper type and an air blowing execution flag according to the first embodiment, and a method for prohibiting the setting of a paper type that requires an air blowing operation. FIG. 10 is a table showing the relationship between paper type and necessity for air blowing according to the first embodiment.

[0047] The sheet paper type is set from the operation unit 700. In other words, the operation unit 700 also serves as a setting unit for setting the type of sheet. As shown in FIG. 6, the operation unit 700 is provided with a start key 702 for starting an image forming operation and a stop key 703 for interrupting the image forming operation as an input unit for inputting instructions. The operation unit 700 further includes numeric keys 704 to 712 and 714 for setting numbers, an ID key 713, a clear key 715, a reset key 716, and the like. The operation unit 700 also includes a display unit 720 with a touch panel formed on the upper portion, and soft keys can be created on the screen.

[0048] Here, the display unit 720 includes an LCD (LCD stands for Liquid Crystal Display) that displays a setting screen and the status of the image forming apparatus 201, and a touch panel for inputting instructions to the image forming apparatus 201. The LCD displays a screen for making settings related to image formation, such as the number of images to be formed, the type of sheet, and size settings, and settings related to image reading, such as setting the size of the document, as information related to image formation. The LCD also displays the status of the image forming apparatus, such as whether image formation processing is in progress, whether it has stopped due to an error, or whether it is in standby mode, as information related to image formation.

[0049] The touch panel is disposed so as to overlap the LCD in a direction perpendicular to the display surface of the LCD. Specifically, when the user looks at the screen, the touch panel is disposed closer to the user than the LCD. Since the touch panel is disposed closer to the user than the LCD, the surface of the touch panel that the user touches corresponds to the surface of the display unit 720.

[0050] Here, the configuration in which the sheet paper type setting is set from the operation unit 700 is exemplified, but the present invention is not limited to this. For example, the sheet paper type setting may be set from the host device 900. Also, a display unit with a touch panel formed on the upper portion is exemplified as the display unit 720, but the present invention is not limited to this. Any other display unit may be used as long as it displays a setting screen or information to be notified to the user.

[0051] When the user presses the "paper selection" button on the display unit 720 shown in FIG. 6, the CPU 101 transitions to a paper feed tray setting screen shown in FIG. 7(a) (S601).

[0052] First, select which sheet placement unit (manual feed tray 6, feeding cassette 1, feeding deck 500) to set the sheets for. Here, the "Manual Feed" button indicating the manual feed tray 6 is selected (S601, S602), and the "Next" button is pressed. When the button is pressed, the CPU 101 transitions to the paper size setting screen shown in Fig. 7(b) (S603). Here, the "A3" button, which is the paper size set in the manual feed tray 6, is selected (S603, S604), and the "Next" button is pressed.

[0053] When the button is pressed, the process proceeds to fan failure judgment (S611), and the fan control unit 402 judges whether or not one or both of the fan motors 511M, 512M are broken.

[0054] If the fan motors 511M, 512M are broken, the process proceeds to S605, and the paper type selection screen shown in Fig. 8(b) is displayed. The paper type selection screen shown in Fig. 8(b) is a setting screen for basis weight and paper type when the fan motors 511M, 512M are broken, and the selection buttons for Coated Paper 1, Coated Paper 2, and Coated Paper 3 are grayed out and cannot be selected. This is because when the fan motors 511M, 512M are broken, the air blowing operation cannot be performed, and Coated Paper 1, Coated Paper 2, and Coated Paper 3, which have high adhesion, may cause a jam, so selection by the user is prohibited.

[0055] That is, when the fan control unit 402 detects a failure of the air blowing units 511A and 512A (S611), the setting of a sheet determined to require the blowing operation by the air blowing units 511A and 512A is prohibited (S605). This allows the CPU 101 to prevent the selection of a sheet determined to require the blowing operation by the air blowing units 511A and 512A on the operation unit 700, as shown in FIG. 8(b). At the same time, when the fan control unit 402 detects a failure of the air blowing units 511A and 512A (S611), the setting is limited to a sheet determined to not require the blowing operation by the air blowing units 511A and 512A. This allows the CPU 101 to limit the selection of a sheet determined to not require the blowing operation by the air blowing units 511A and 512A on the operation unit 700, as shown in FIG. 8(b).

[0056] On the other hand, if the fan motors 511M, 512M are not malfunctioning, the process proceeds to S612, and the paper type selection screen shown in Fig. 8(a) is displayed. The paper type selection screen shown in Fig. 8(a) is a setting screen for basis weight and paper type when the fan motors 511M, 512M are not malfunctioning, and all selection buttons, including Coated Paper 1, Coated Paper 2, and Coated Paper 3, can be selected by the user.

[0057] On the paper type selection screen (S605, S612) shown in Figure 8(b) or Figure 8(a), select the basis weight and paper type of the sheet set on the sheet loading section and press the ``OK'' button, and the display will transition to the initial screen shown in Figure 6, and the paper type selection process will be completed (S606).

[0058] Furthermore, CPU 101 determines whether or not the blowing operation of the set sheet is necessary based on a judgment table (see FIG. 10) of paper type and air blowing necessity stored in ROM 102, and sets an air blowing execution flag (S607). If the selected sheet type (basis weight and paper type) indicates that air blowing is "necessary," the air blowing execution flag is set to ON (to be executed) (S608). On the other hand, if the selected sheet type (basis weight and paper type) indicates that air blowing is "not required," the air blowing execution flag is set to OFF (not to be executed) (S609).

[0059] It should be noted that the relationship between the paper type (basis weight and paper type) and the necessity for air blowing shown in FIG. 10 is merely an example, and is not limiting.

[0060] The paper information and air blowing execution flag set here are associated with the selected paper feed tray and stored in the RAM 103 (S610).

[0061] After setting the paper information, when the start key 702 of the operation unit 700 is pressed, the job is started and a sheet is fed from the selected sheet placement unit. That is, as described with reference to Fig. 5, in accordance with the settings stored in the RAM 103, the air blowing units 511A and 512A selectively perform a blowing operation, and the sheet feeding unit 506 performs a feeding operation.

[0062] It should be noted that the paper information does not need to be set each time before starting a job because it is stored in the RAM 103. For example, if you want to execute a job in which A3-sized plain paper is fed from the manual feed tray again after loading A3-sized plain paper in the manual feed tray, all you have to do is press the start key 702.

[0063] [Method of informing a user before starting a supply operation according to the first embodiment] Next, a method of notifying a user will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a flowchart showing a method of notifying a user according to the first embodiment, which is executed immediately before starting a feeding operation. Fig. 12 is an explanatory diagram of a notification message according to the first embodiment.

[0064] In S101, the CPU 101 determines whether the selected paper feed tray is one to which air can be blown. In this embodiment, the selected paper feed tray is acquired from the RAM 103, and if the acquired paper feed tray is "manual feed," the process proceeds to S102. If the acquired paper feed tray is not "manual feed," the process ends this flow chart.

[0065] If the paper feed tray acquired in S102 is "manual feed", the CPU 101 determines whether or not the fan motors 511M and 512M are broken by the fan control unit 402. If they are broken, the process proceeds to S103, and if they are not broken, the process ends.

[0066] If the fan motors 511M, 512M are broken, the CPU 101 judges whether or not separation is necessary based on the air blowing execution flag stored in the RAM 103 (S103). If the air blowing execution flag is "ON", the process proceeds to S104, and a message is displayed on the display unit 720, as shown in Fig. 12, indicating that the separation fan is broken and that a jam may occur with the current settings. This message can be hidden by pressing the "Close" button.

[0067] By displaying the above-mentioned message (see FIG. 12) in S104, it is possible to notify the user even if the fan breaks down after the sheets are set. For example, if a job is executed by placing multiple sheets of a paper type that needs to be separated on the manual feed tray while the fan motor is not broken, and the fan motor breaks down after the job is completed, and then another job is executed, it is possible to notify the user.

[0068] According to this embodiment, even if the air blowing device breaks down, the setting of only the sheets that require the air blowing operation is prohibited and not executed, so that sheets that do not require the air blowing operation can be fed even if multiple sheets are placed. This makes it possible to prevent a decrease in usability.

[0069] Example 2 Next, an image forming system including a sheet feeding device according to the second embodiment will be described. The image forming system 600, the image forming apparatus 201, the manual feeding section 235, the configuration of the control system of the image forming system 600, the operation during air blowing, and the sheet feeding control are the same as those in the above-mentioned embodiment, so detailed explanations will be omitted here. In the following explanation, members having the same functions as those in the above-mentioned embodiment will be described with the same reference numerals.

[0070] In this embodiment, the method of setting sheet information and the air blowing execution flag, and the method of notifying the user are different from the above-described embodiments.

[0071] [Method of Setting Sheet Information and Air Blowing Execution Flag According to the Second Embodiment] Here, we will explain how to set sheet information such as the paper size, paper type, and basis weight of the sheet set in the manual feed tray 6, and how to set the air blowing execution flag mentioned above, with reference to Figures 6 to 8(b), 13 and 10.

[0072] FIG. 13 is a flowchart showing a paper type and air blowing execution flag setting method according to the second embodiment.

[0073] The sheet paper type setting is made from an operation unit 700. As shown in Fig. 6, the operation unit 700 is provided with a start key 702 for starting an image forming operation and a stop key 703 for interrupting the image forming operation as an input unit for inputting instructions. The operation unit 700 is further provided with numeric keys 704 to 712 and 714 for setting numbers and the like, an ID key 713, a clear key 715, a reset key 716, and the like. The operation unit 700 is also provided with a display unit 720 with a touch panel formed on the upper portion, and soft keys can be created on the screen.

[0074] Here, the configuration in which the sheet paper type setting is set from the operation unit 700 is exemplified, but the present invention is not limited to this. For example, the sheet paper type setting may be set from the host device 900. Also, a display unit with a touch panel formed on the upper portion is exemplified as the display unit 720, but the present invention is not limited to this. Any other display unit may be used as long as it displays a setting screen or information to be notified to the user.

[0075] When the user presses the "paper selection" button on the display unit 720 shown in FIG. 6A, the CPU 101 transitions to a paper feed stage selection screen shown in FIG. 7A (S701).

[0076] First, select which sheet placement unit (manual feed tray 6, feeding cassette 1, feeding deck 500) to set the sheets for. Here, select the "Manual Feed" button indicating the manual feed tray 6 (S701, S702), and press the "Next" button. When the button is pressed, the CPU 101 transitions to the paper size setting screen shown in FIG. 7(b) (S703). Here, select the "A3" button, which is the paper size set in the manual feed tray 6 (S703, S704), and press the "Next" button.

[0077] When the button is pressed, the CPU 101 transitions to a paper type selection screen shown in Fig. 8(a) (S705). The screen transitions to a setting screen for basis weight and paper type. The paper type selection screen shown in Fig. 8(a) is a setting screen for paper type (basis weight and paper type), and all selection buttons can be selected by the user.

[0078] On the paper type selection screen (S705) shown in FIG. 8(a), the user selects the basis weight and paper type of the sheet set on the sheet loading section and presses the "OK" button, which transitions to the initial screen shown in FIG. 6 and completes the paper type selection process (S706).

[0079] Furthermore, CPU 101 determines whether or not the blowing operation for the set sheet is necessary based on a judgment table (see FIG. 10) of paper type and air blowing necessity stored in ROM 102, and sets an air blowing execution flag (S707). If the selected sheet type (basis weight and paper type) indicates that air blowing is "necessary," the air blowing execution flag is set to ON (to be executed) (S708). On the other hand, if the selected sheet type (basis weight and paper type) indicates that air blowing is "not required," the air blowing execution flag is set to OFF (not to be executed) (S709).

[0080] It should be noted that the relationship between the paper type (basis weight and paper type) and the necessity for air blowing shown in FIG. 10 is merely an example, and is not limiting.

[0081] The sheet information and air blowing execution flag set here are associated with the selected paper feed tray and stored in the RAM 103 (S710).

[0082] After setting the paper information, when the start key 702 of the operation unit 700 is pressed, the job is started and a sheet is fed from the selected sheet placement unit. That is, as described with reference to Fig. 5, in accordance with the settings stored in the RAM 103, the air blowing units 511A and 512A selectively perform a blowing operation, and the sheet feeding unit 506 performs a feeding operation.

[0083] It should be noted that the paper information does not need to be set each time before starting a job because it is stored in the RAM 103. For example, if you want to execute a job in which A3-sized plain paper is fed from the manual feed tray again after loading A3-sized plain paper in the manual feed tray, all you have to do is press the start key 702.

[0084] [First notification method for a user according to the second embodiment] Next, a first method of notifying a user will be described with reference to Fig. 11 and Fig. 14. Fig. 11 is a flowchart showing a method of notifying a user according to the first embodiment, which is executed when the sheet information setting and the air blowing execution flag setting described above are completed. Fig. 14 is an explanatory diagram of a first notification message according to the second embodiment.

[0085] In S101, the CPU 101 determines whether the selected paper feed tray is one to which air can be blown. In this embodiment, the selected paper feed tray is acquired from the RAM 103, and if the acquired paper feed tray is "manual feed," the process proceeds to S102. If the acquired paper feed tray is not "manual feed," the process ends this flow chart.

[0086] If the paper feed tray acquired in S102 is "manual feed", the CPU 101 determines whether or not the fan motors 511M, 512M are malfunctioning using the fan control unit 402. If they are malfunctioning, the process proceeds to S103, and if they are not malfunctioning, the process ends this flow chart.

[0087] If the fan motors 511M, 512M are broken, the CPU 101 judges whether or not separation is necessary from the air blowing execution flag stored in the RAM 103 (S103). If the air blowing execution flag is "ON", the process proceeds to S104, and a message is displayed indicating that the separation fan is broken and prompting the user to place one sheet on the manual feed tray 6, as shown in Fig. 14. This message can be hidden by pressing the "Close" button.

[0088] By displaying the aforementioned message (see FIG. 14) in S104, when the fan is broken and the user places a sheet that requires air blowing into the manual feed tray 6, the job is executed as is, making it possible to prevent a paper jam from occurring.

[0089] 11 is executed when the sheet information setting and the air blowing execution flag setting described above are completed, but the present invention is not limited to this. For example, the control shown in FIG. 11 may be executed when a job is started, that is, when start key 702 of operation unit 700 is pressed. In other words, when a feeding start instruction is input by pressing start key 702, CPU 101 may detect a fan failure by fan control unit 402 and, if a sheet type that is determined to require a blowing operation is stored in RAM 103, display a message prompting the user to place one sheet on the manual feed tray.

[0090] 11 at the start of a job, it is possible to notify the user even if the fan breaks down after the sheets are set. For example, if a job is executed by placing multiple sheets of a paper type that needs to be separated on the manual feed tray while the fan motor is not broken, and the fan motor breaks down after the job is completed, and then another job is executed, it is possible to notify the user.

[0091] [Second method of notifying user according to the second embodiment] Next, the second method of notifying the user will be described with reference to Fig. 15 and Fig. 16. Fig. 15 is a flow chart showing the second method of notifying the user according to the second embodiment, which is executed every time a predetermined time has elapsed since the power supply of the image forming system 600 is turned on. Fig. 16 is an explanatory diagram of the second notification message according to the second embodiment.

[0092] In S201, the CPU 101 determines from the fan control unit 402 whether or not one or both of the fan motors 511M and 512M are malfunctioning.

[0093] If the fan motors 511M, 512M are broken, the process proceeds to S202, and a message is displayed on the display unit 720 to notify the user to limit the number of sheets placed on the manual feed tray 6. Specifically, as shown in FIG. 16, a message is displayed on the display unit 720 saying "Recommended to place one sheet on the manual feed tray (coated paper)."

[0094] On the other hand, if the fan motors 511M, 512M are not broken, the process proceeds to S203, and the message notifying the user that there is a loading limit for the manual feed tray 6 is made invisible.

[0095] By displaying the message shown in FIG. 16 in S202, the user can place one sheet of the paper type that needs to be separated on the manual feed tray, thereby making it possible to prevent paper jams from occurring when a job is executed.

[0096] According to this embodiment, even if the air blowing fan breaks down, the user is notified that one sheet must be placed, so that the sheets can be fed continuously even if the sheets require air blowing. Also, by notifying only when air blowing is required, sheets that do not require air blowing can be fed even if multiple sheets are placed.

[0097] Other Examples In the embodiment described above, when fan control unit 402 detects a failure of air blowing units 511A, 512A, a configuration (FIGS. 12 and 14) is illustrated in which information indicating that air blowing units 511A, 512A have failed is displayed on display unit 720, but the present invention is not limited to this. For example, information indicating that air blowing units 511A, 512A have failed may be displayed on display unit 720 until fan control unit 402 no longer detects a failure of air blowing units 511A, 512A.

[0098] In the above-mentioned embodiment, the sheet feeding control in the manual feed section 235 having the air blowing sections 511A and 512A has been described, but the present invention is not limited to this. For example, the above-mentioned sheet feeding control may be performed in the sheet feeding unit 230 having the feed cassette 1, or in the feed deck 500 having the deck section 510 having an air blowing section. In addition, when the above-mentioned sheet feeding control is performed in the sheet feeding unit 230, it may be performed in any of the vertical feed stages. In other words, the sheet support section that supports the sheet stack may have any configuration.

[0099] In the above-mentioned embodiment, the sheet feeding and separation device is provided with a pickup roller for feeding the sheets, and a feed roller and a retard roller for separating overlapped sheets, but the present invention is not limited to this. For example, the sheet feeding unit may have any configuration for feeding the sheets, such as a device that feeds the sheets by vacuum adsorbing them to a belt or the like.

[0100] In the above-described embodiment, the control unit 100 is provided in the image forming apparatus 201, but the present invention is not limited to this. For example, the control unit may be provided in the feeding deck 500 serving as a sheet feeding device. In other words, as long as a control unit capable of controlling the sheet feeding unit and the air blowing unit is electrically connected to them, the control unit may be disposed in either device.

[0101] The present invention can also be realized by supplying a program for implementing one or more of the functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) for implementing one or more of the functions.

[0102] In the above embodiment, the recording method is an electrophotographic method, but the recording method is not limited to this, and other recording methods such as an inkjet method may also be used. [Explanation of symbols]

[0103] S...Seat 1 ... Feeding cassette (sheet placement section) 6... Manual feed tray (sheet placement area) 100 ... control unit 101...CPU 102 ... ROM (storage section) 103...RAM (storage unit) 201 ... Image forming device 201B...Image forming section 235 ... Manual feeding section (sheet feeding device) 402 ... Fan control unit (failure detection unit) 500 ... Feeding deck (sheet placement area) 506 ...Sheet feeding section 511, 512 ... Side end regulating plate (regulating member) 511A, 512A ... Air blowing section (air handling section) 511M, 512M ... Fan motor 600 ... Image forming system 700 ... Operation section (setting section) 702 ... Start key (input section) 720…Display section

Claims

1. a sheet placement section capable of placing a plurality of sheets; a sheet feeding section that feeds a sheet placed on the sheet placement section; an air handling unit that performs a blowing operation of blowing air onto the sides of the plurality of sheets placed on the sheet placement unit to handle the sheets; A setting section for setting the type of sheet; a storage unit that stores the type of sheet set by the setting unit; a control unit that determines whether or not the blowing operation by the air handling unit is required depending on the type of sheet set by the setting unit; A failure detection unit that detects a failure of the air handling unit, The control unit, when the failure detection unit detects a failure of the air handling unit, prohibits the setting of a sheet for which it is determined that the blowing operation by the air handling unit is necessary, and limits the setting of a sheet to a setting for which it is determined that the blowing operation by the air handling unit is not necessary.

2. 2. The sheet feeding device according to claim 1, wherein the control unit prevents the setting unit from selecting a sheet for which the air handling unit is determined to require the blowing operation, and limits the selection to a sheet for which the air handling unit is determined to not require the blowing operation.

3. 2 . The sheet feeding device according to claim 1 , wherein the control unit notifies a user that the air handling unit has failed when the failure detection unit detects a failure in the air handling unit.

4. A display unit for displaying information is provided, 4. The sheet feeding device according to claim 3, wherein the control unit, when a failure of the air handling unit is detected after the type of sheet is set and it is determined that the set sheet requires the blowing operation by the air handling unit, displays information on the failure of the air handling unit on the display unit.

5. a sheet placement section capable of placing a plurality of sheets; a sheet feeding section that feeds a sheet placed on the sheet placement section; an air handling unit that performs a blowing operation of blowing air onto the sides of the plurality of sheets placed on the sheet placement unit to handle the sheets; A setting section for setting the type of sheet; a storage unit that stores the type of sheet set by the setting unit; a control unit that determines whether or not the blowing operation by the air handling unit is required depending on the type of sheet set by the setting unit; A failure detection unit that detects a failure of the air handling unit, The sheet feeding device according to claim 1, wherein the control unit issues a notification to limit the number of sheets placed on the sheet placement unit when the failure detection unit detects a failure in the air handling unit.

6. A display unit for displaying information is provided, The sheet feeding device according to claim 5, characterized in that the control unit displays information on the display unit limiting the number of sheets to be placed on the sheet placement unit to one when the failure detection unit detects a failure of the air handling unit and a type of sheet for which it is determined that the blowing operation by the air handling unit is required is set.

7. A display unit for displaying information is provided, The sheet feeding device according to claim 5, characterized in that the control unit detects whether or not the air handling unit has failed using the failure detection unit every time a predetermined time has elapsed since the power was turned on, and if the failure detection unit detects a failure of the air handling unit, displays information to limit the number of sheets that can be placed on the sheet placement unit to one.

8. A display unit for displaying information; An input unit for inputting an instruction, The sheet feeding device according to claim 5, characterized in that when an instruction to start feeding is input by the input unit, the control unit detects a failure of the air handling unit by the failure detection unit, and when the type of sheet for which the blowing operation is determined to be necessary is stored in the memory unit, the control unit displays information on the display unit limiting the number of sheets to be placed on the sheet placement unit to one.

9. a storage unit that stores a table indicating the relationship between the type of sheet and whether or not a blowing operation is required; 6. The sheet feeding apparatus according to claim 1, wherein the control unit determines whether or not the blowing operation of the set sheet is required based on a table stored in the storage unit.

10. a storage unit that stores a table indicating the relationship between the type of sheet and whether or not a blowing operation is required; The control unit sets an execution flag for the blowing operation in the memory unit to ON when the set type of sheet requires a blowing operation, and sets an execution flag for the blowing operation in the memory unit to OFF when the set type of sheet does not require a blowing operation, selectively performs the blowing operation by the air handling unit in accordance with the settings stored in the memory unit, and performs a feeding operation by the sheet feeding unit.

11. a regulating member that is movable in a width direction perpendicular to a sheet feeding direction and that regulates a position of an end of a sheet in the width direction placed on the sheet placement portion; 6. The sheet feeding device according to claim 1, wherein the regulating member is provided with the air handling portion.

12. An image forming system including an image forming apparatus including an image forming unit that forms an image on a sheet, and a sheet feeding unit that feeds a sheet to the image forming unit, 9. An image forming system comprising the sheet feeding section according to claim 1 as the sheet feeding section.

Images