Static eliminator and image forming system

Abstract

To provide a static eliminator that can easily confirm whether or not the ionizer needs maintenance.SOLUTION: A static eliminator 200 eliminates static electricity on a sheet S output from an image forming device 100. The static eliminator comprises: an ionizer 46; a frame 57 that houses the ionizer and a control section; and an LED 56 that displays an indicative content corresponding to an alarm signal output from the ionizer The LED is mounted on an exterior surface of the frame.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a static eliminator that eliminates static electricity from a recording medium output from an image forming apparatus, and to an image forming system. [Background technology]

[0002] In image forming apparatuses such as copying machines, printers, and facsimile machines using electrophotography or electrostatic recording, sheets (recording media) may become charged during image formation, and the sheets may stick to each other due to electrostatic forces generated between discharged sheets, resulting in stacking failure. In view of this, an image forming apparatus equipped with a static elimination device for eliminating static electricity from sheets has been proposed. The static elimination device described in Patent Document 1 has a contact type static elimination section that contacts the conveyed sheet to eliminate static electricity, and a non-contact type static elimination section that eliminates static electricity without contacting the sheet. As a contact type static elimination section, a static elimination roller pair that nips the sheet to eliminate static electricity is known. As a non-contact type static elimination section, one that generates ions using a discharge wire or a needle-shaped electrode is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-167169 A Summary of the Invention [Problem to be solved by the invention]

[0004] When the non-contact static electricity removal unit is used continuously, organic matter in the air may be deposited on the electrode portion, and the static electricity removal performance of the non-contact static electricity removal unit may be deteriorated. Therefore, it is desirable to clean the non-contact static electricity removal unit as necessary. However, in a static electricity removal device, since the non-contact static electricity removal unit is housed inside a housing, it is difficult for a user to determine whether or not maintenance of the non-contact static electricity removal unit is required. Therefore, an object of the present invention is to provide a static electricity removal device that allows a user to easily check whether or not maintenance of the non-contact static electricity removal unit is required. [Means for solving the problem]

[0005] One embodiment of the present invention is a static elimination device that eliminates static electricity from a sheet on which an image is formed by an image forming apparatus, comprising a conveying means that receives a sheet from the image forming apparatus and conveys it, a non-contact static elimination means that eliminates static electricity from the sheet without coming into contact with the sheet conveyed by the conveying means, a frame that houses the conveying means and the non-contact static elimination means, and a display unit provided on the exterior surface of the frame that displays display content corresponding to a predetermined signal output from the non-contact static elimination means based on whether maintenance is required for the non-contact static elimination means. Effect of the Invention

[0006] According to the present invention, it is possible to provide a static eliminator that allows a user to easily check whether or not maintenance of the non-contact static eliminator is required. [Brief description of the drawings]

[0007] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. 4 is a block diagram showing an ionizer, an LED, and a control unit. [Figure 4] 4 is a flowchart of the control operation of the ionizer and the LED. [Diagram 5] 11 is a flowchart of a maintenance detection full control operation at the end of a print job. [Figure 6] 11 is a flowchart of a maintenance detection interruption control operation when a print job is completed. [Figure 7] 11 is a flowchart of a maintenance detection full control operation when power is turned on to the static eliminator. [Figure 8] 13 is a flowchart of a maintenance detection interruption control operation when power is turned on to the static eliminator. [Figure 9] 11 is a flowchart of a maintenance detection full control operation when the door of the static eliminator is opened and closed. [Figure 10] 11 is a flowchart of a maintenance detection interruption control operation when the door of the static eliminator is opened or closed. [Figure 11] FIG. 1 illustrates an image forming system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the attached drawings. Note that unless otherwise specified, the dimensions, materials, and relative positions of the components of the image forming apparatus 100 and the static eliminator 200 are not intended to limit the scope of the present invention. Also, the same reference numerals in each drawing denote the same configurations or functions, and duplicated descriptions of these will be omitted as appropriate.

[0009] <Image forming device> FIG. 1 is a cross-sectional view of an image forming apparatus 100. The image forming apparatus 100 forms an image on a recording medium (hereinafter referred to as a sheet) using an electrophotographic process. As shown in FIG. 1, photosensitive drums (latent image carriers) 1Y, 1M, 1C, and 1K rotate in the direction indicated by the arrow A. The surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K are uniformly charged by charging devices 2Y, 2M, 2C, and 2K. The exposure devices 3Y, 3M, 3C, and 3K expose the uniformly charged surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K to light in accordance with image information, thereby forming electrostatic latent images on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K. The developing devices 4Y, 4M, 4C, and 4K develop the electrostatic latent images with yellow (Y) toner, magenta (M) toner, cyan (C) toner, and black (K) toner, respectively, to form toner images on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K. In this embodiment, the developing devices 4Y, 4M, 4C, and 4K use a reversal development method in which toner is deposited on the exposed portion of the electrostatic latent image to develop it.

[0010] The intermediate transfer belt 6 is disposed so as to contact the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K. The intermediate transfer belt 6 is stretched around a plurality of tension rollers 20, 21, 22, 23, 24, and 25 and rotates in the direction indicated by the arrow G at a rotation speed of 150 to 470 mm / sec. In this embodiment, the tension roller 20 is a tension roller that keeps the tension of the intermediate transfer belt 6 constant. The tension roller 22 is a drive roller that drives the intermediate transfer belt 6. The tension roller 21 is an inner roller for secondary transfer. The outer roller 9 for secondary transfer is disposed opposite the tension roller 21 via the intermediate transfer belt 6. The outer roller 9 for secondary transfer conveys the sheet S by nipping it at a secondary transfer nip (secondary transfer portion) between the outer roller 9 for secondary transfer and the intermediate transfer belt 6.

[0011] The primary transfer rollers 5Y, 5M, 5C, and 5K are disposed facing the photosensitive drums 1Y, 1M, 1C, and 1K via the intermediate transfer belt 6, and form primary transfer nips (primary transfer portions) between the intermediate transfer belt 6 and the photosensitive drums 1Y, 1M, 1C, and 1K. In synchronization with the conveyance of the toner images of each color on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K to the respective primary transfer nips, a constant voltage controlled transfer bias of the opposite polarity to the toner images is applied to the primary transfer rollers 5Y, 5M, 5C, and 5K. As a result, the toner images on the surfaces of the photosensitive drums 1Y, 1M, 1C, and 1K are transferred onto the intermediate transfer belt 6 (primary transfer).

[0012] The registration roller 8 conveys the sheet S to the secondary transfer nip in synchronization with the toner image on the intermediate transfer belt 6 being conveyed to the secondary transfer nip. The pre-secondary transfer conveying guide 11 improves the conveying accuracy when conveying the sheet S to the secondary transfer nip. The high voltage application means 10 applies a constant voltage controlled transfer bias of a polarity opposite to that of the toner image to the outer roller 9 for secondary transfer. As a result, the toner image on the intermediate transfer belt 6 is transferred onto the sheet S (secondary transfer). The sheet S onto which the toner image has been transferred is conveyed to the fixing device 40 by the pre-fixing conveying device 41. The pre-fixing conveying device 41 has a rotating belt body, and conveys the sheet S on it. The fixing device 40 heats and presses the sheet S to fix the toner image onto the sheet S. The belt cleaning device 12 electrostatically collects and cleans the secondary transfer residual toner on the intermediate transfer belt 6. The cleaned intermediate transfer belt 6 is used repeatedly for image formation.

[0013] <Static eliminator> FIG. 2 is a schematic diagram of the static elimination device 200. The static elimination device 200 is disposed downstream of the image forming device 100 in the conveying direction CD of the sheet S. The static elimination device 200 receives the sheet S on which an image is formed from the image forming device 100, and eliminates static from the sheet S as a medium to be neutralized. The static elimination device 200 may be directly connected to the image forming device 100, or may be connected to the image forming device 100 via a post-processing device such as an inserter. FIG. 11 is a diagram showing an image forming system 300. The image forming system 300 includes the image forming device 100 and a static elimination device 200 disposed downstream of the image forming device 100 in the conveying direction CD of the sheet S. The image forming device 100 and the static elimination device 200 may be integrally formed to constitute the image forming device 100.

[0014] The static eliminator 200 has a frame (housing) 57. The frame 57 houses the pair of static eliminator rollers 45, the ionizer 46, the transport guide 53, the high voltage board 55, and a control unit 58 that controls the entire static eliminator 200. The frame 57 is provided with an LED (light emitting diode) 56 that serves as an indicator that indicates the state of the ionizer 46. The LED 56 is disposed on the exterior surface of the frame 57 so that the user can check the display content of the LED 56 from outside the frame 57.

[0015] The discharge roller pair 45 is a contact type discharge means that contacts the sheet S to discharge the sheet S. The discharge roller pair 45 is a conveying means that receives and conveys the sheet discharged from the image forming apparatus 100. The discharge roller pair 45 includes a discharge roller 50 and a discharge counter roller 51 disposed opposite the discharge roller 50. The discharge roller 50 and the discharge counter roller 51 are pressed against each other to form a discharge nip. The high voltage board 55 generates a high voltage and applies the high voltage to the discharge roller 50. The discharge roller 50 and the discharge counter roller 51 sandwich the sheet S in the discharge nip and discharge the sheet S while conveying it. The discharge device 200 may be configured to have an inlet roller pair as a conveying means that receives and conveys the sheet discharged from the image forming apparatus 100 on the upstream side of the discharge roller pair 45. In this embodiment, the charge removing roller pair 45 is disposed upstream of the ionizer 46 in the transport direction CD.

[0016] The ionizer 46 is disposed downstream of the pair of charge removing rollers 45 in the conveying direction CD of the sheet S. The ionizer 46 has electrode needles (discharge needles) 52a and 52b disposed above and below a conveying guide 53 that forms a conveying path. The electrode needle 52a (first charge removing member) is disposed facing the upper surface (first surface) of the sheet S being conveyed. The electrode needle 52b (second charge removing member) is disposed facing the lower surface (second surface) opposite to the upper surface of the sheet S being conveyed. The ionizer 46 is a non-contact charge removing means that removes charge from the sheet S without contacting the sheet S passing through the conveying guide 53. The ionizer 46 of this embodiment uses a corona discharge method in which an AC high voltage (alternating voltage) is applied to the electrode needles 52a and 52b to alternately generate positive ions and negative ions. The front and back surfaces of the sheet S are alternately irradiated with positive and negative ions from the electrode needles 52a and 52b of the ionizers 46 arranged above and below the sheet S, thereby simultaneously eliminating electricity from the front and back surfaces of the sheet S, regardless of the polarity of the charge on the sheet S. That is, in this embodiment, the electrode needles 52a and 52b are arranged at the same position in the transport direction CD.

[0017] The LED 56 is switched between on, blinking, and off according to the state of the ionizer 46. The LED 56 is attached to an upper surface 57a on the exterior surface of the frame body 57 so that the user can check the on, blinking, and off state of the LED 56 from outside the frame body 57. The LED 56 may be attached to a front surface 57b on the exterior surface of the frame body 57. In this embodiment, the surface facing upward in the vertical direction on the exterior surface of the frame body 57 is the upper surface 57a. Also, the surface facing the front side of the static eliminator 200 on the exterior surface of the frame body 57 is the front surface 57b. That is, the front surface 57b also includes an inclined surface inclined so as to intersect with the vertical direction.

[0018] The sheet S conveyed from the image forming apparatus 100 is first roughly cleaned of the electrostatic charge of the sheet S in the electrostatic elimination nip between the electrostatic elimination roller 50 and the electrostatic elimination opposing roller 51. The high voltage applied to the electrostatic elimination roller 50 has a polarity opposite to that of the voltage applied to the outer roller 9 for secondary transfer. Next, the ionizer 46 removes the electric charge from the sheet S that was not completely eliminated by the electrostatic elimination roller pair 45. The sheet S that has been electrostatically eliminated by the electrostatic elimination roller pair 45 and the ionizer 46 is discharged to the outside of the electrostatic elimination device 200.

[0019] 3 is a block diagram showing the ionizer 46, the LED 56, and the control unit 58. The ionizer 46 switches between an ON state in which ions are generated and an OFF state in which ion generation is stopped according to an ionizer ON / OFF signal 101 output from the control unit 58. When the ionizer ON / OFF signal 101 is at H level (high level), the ionizer 46 is in the ON state in which ions are generated. When the ionizer ON / OFF signal 101 is at L level (low level), the ionizer 46 is in the OFF state in which ion generation is stopped. The control unit 58 controls the ionizer 46 by switching the ionizer ON / OFF signal 101 at a predetermined timing to switch between an ion generation state and an ion stop state.

[0020] The ionizer 46 transitions to a maintenance detection mode in which maintenance detection is performed to determine whether or not maintenance is required, triggered by the switching of the maintenance detection mode transition signal 102 output from the control unit 58 from L level to H level. The ionizer 46 determines whether or not maintenance is required during the maintenance detection mode. Whether or not maintenance is required is reflected in a maintenance detection signal (alarm signal) 103, which is a predetermined signal. An L level maintenance detection signal 103 indicates that maintenance of the ionizer 46 is not required. An H level maintenance detection signal 103 indicates that maintenance of the ionizer 46 is required. The ionizer 46 outputs the maintenance detection signal 103 to the control unit 58.

[0021] The control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level at a predetermined timing to transition the ionizer 46 to the maintenance detection mode. When the control unit 58 receives the H level maintenance detection signal 103 from the ionizer 46, it determines that maintenance of the ionizer 46 is required. When it determines that maintenance of the ionizer 46 is required, the control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to flash.

[0022] The ionizer 46 can detect abnormalities such as abnormal discharges that occur when a conductor approaches the vicinity of the electrode needles 52a and 52b. When the ionizer 46 is operating normally, the ionizer 46 outputs an abnormality detection signal (alarm signal) 104 of L level to the control unit 58. When the ionizer 466 detects an abnormality, it outputs an abnormality detection signal 104 of H level to the control unit 58. When the control unit 58 receives the abnormality detection signal 104 of H level while the ionizer ON / OFF signal 101 is at H level, it determines that the ionizer 46 is in an abnormal state. When the control unit 58 detects an abnormality in the ionizer 46, it switches the LED control signal 105 to H level to turn on the LED 56.

[0023] The control unit 58 blinks the LED 56 when it determines that maintenance is required for either of the electrode needles 52a and 52b of the ionizer 46 arranged above and below. The control unit 58 lights up the LED 56 when it determines that either of the electrode needles 52a and 52b is in an abnormal state. Since the ionizer 46 is arranged inside the frame body 57, it is difficult for the user to visually check the ionizer 46 and determine whether the ionizer 46 needs maintenance or whether there is an abnormality. Therefore, by providing the LED 56 (display unit) on the frame body 57 so that the user can visually check the display content from outside the frame body 57, it is possible to notify the user that the ionizer 46 needs maintenance at an appropriate time. This allows the user to recognize the need for maintenance at an appropriate time, so that early deterioration of the electrode needles 52a and 52b due to excessive maintenance and insufficient static elimination ability due to insufficient maintenance can be prevented. According to this embodiment, the user can easily check whether the ionizer 46 needs maintenance. An abnormal state of the ionizer 46 is, for example, a state in which the ionizer 46 has broken down and is no longer able to neutralize the charge on the sheet.

[0024] FIG. 4 is a flowchart of the control operation of the ionizer 46 and the LED 56. The control unit 58 executes the control operation of the ionizer 46 and the LED 56 according to a program stored in the storage unit 59. When the control operation of the ionizer 46 and the LED 56 is started, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON (S101). The ionizer 46 starts generating ions. The control unit 58 judges whether the abnormality detection signal 104 is at H level or not (S102). If the abnormality detection signal 104 is at H level (YES in S102), the control unit 58 switches the LED control signal 105 to H level to turn on the LED 56 (S110) and ends the control operation.

[0025] In this embodiment, the display content is displayed on the LED 56 in a pattern (second display pattern) in which the LED 56 is lit when the ionizer 46 is abnormal. However, the display content may be displayed on the LED 56 in a pattern in which the LED 56 blinks when maintenance of the ionizer 46 is required. The LED 56 may display the display content corresponding to the abnormality detection signal 104 output from the ionizer 46 in a predetermined pattern.

[0026] When the abnormality detection signal 104 is at the L level (NO in S102), the control unit 58 judges whether or not to transition to the maintenance detection mode (S103). When the maintenance detection mode is not to be transitioned to (NO in S103), the control unit 58 advances the process to S104. On the other hand, when the maintenance detection mode is to be transitioned to (YES in S103), the control unit 58 switches the maintenance detection mode transition signal 102 from the L level to the H level to start maintenance detection (control to determine whether or not maintenance is necessary) (S106). The control unit 58 judges whether or not the maintenance detection signal 103 at the H level has been received from the ionizer 46 (S107). When the maintenance detection signal 103 at the H level has been received from the ionizer 46 (YES in S107), maintenance of the ionizer 46 is necessary, so the control unit 58 advances the process to S109. The control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to blink (S109), and ends the control operation.

[0027] In this embodiment, when maintenance of the ionizer 46 is required, the display content is displayed on the LED 56 in a pattern (first display pattern) that causes the LED 56 to blink. However, when maintenance of the ionizer 46 is required, the display content may be displayed on the LED 56 in a pattern that causes the LED 56 to light up. One of the first display pattern and the second display pattern may be a pattern that causes the LED 56 to light up, and the other may be a pattern that causes the LED 56 to blink. The LED 56 may display the display content corresponding to the maintenance detection signal 103 output from the ionizer 46 in a predetermined pattern.

[0028] In S107, when the control unit 58 receives the maintenance detection signal 103 at the L level from the ionizer 46 (NO in S107), the control unit 58 judges whether or not to continue the maintenance detection (S108). When the maintenance detection is to be continued (YES in S108), the control unit 58 returns the process to S107. When the maintenance detection is to be interrupted (NO in S108), the control unit 58 advances the process to S104. The control unit 58 judges whether or not to stop the ion generation by the ionizer 46 (S104). When the ion generation is not to be stopped (NO in S104), the control unit 58 returns the process to S102. When the ion generation is to be stopped (YES in S104), the control unit 58 switches the ionizer ON / OFF signal 101 from the H level to the L level to turn the ionizer 46 to the OFF state (S105), and ends the control operation.

[0029] The control timing of the ionizer ON / OFF signal 101 and the maintenance detection mode transition signal 102 in this embodiment will be described with reference to FIG. 5 and FIG. 6. When a print job is started, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON. When the print job is finished, the control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection. In the maintenance detection, it is determined whether or not maintenance of the ionizer 46 is required. A maintenance detection full control operation in which maintenance detection is continued until it is determined that maintenance of the ionizer 46 is required within a predetermined time from the start of maintenance detection or until a predetermined time has elapsed will be described with reference to FIG. 5. In addition, a maintenance detection interruption control operation in which maintenance detection is interrupted when a print job is input during maintenance detection will be described with reference to FIG. 6.

[0030] A user can select between the maintenance detection full control operation shown in Fig. 5 and the maintenance detection interruption control operation shown in Fig. 6, for example, from an operation unit 150 (Fig. 11) provided on the image forming apparatus 100 or the static electricity removal apparatus 200. In this embodiment, both the maintenance detection full control operation shown in Fig. 5 and the maintenance detection interruption control operation shown in Fig. 6 are used, but the present invention is not limited to this. The image forming system 300 may be configured to execute only one of the control operations.

[0031] FIG. 5 is a flowchart of the maintenance detection full control operation at the end of a print job. The control unit 58 executes the maintenance detection full control operation according to a program stored in the storage unit 59. When a print job is input to the image forming apparatus 100, the image forming apparatus 100 starts the print job (image forming operation) (S501). When the print job starts, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON (S502). The control unit 58 determines whether the sheet S on which an image has been formed has passed between the electrode needles 52a and 52b of the ionizer 46 (S503). If the sheet S has not passed through the ionizer 46 (NO in S503), the control unit 58 returns the process to S503 and waits for the sheet S to pass through the ionizer 46. When the sheet S passes through the ionizer 46 (YES in S503), the control unit 58 determines whether the print job has ended (S504). If the print job has not ended (NO in S504), the control unit 58 returns the process to S503. If the print job has ended (YES in S504), the control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (control to determine whether maintenance is necessary) (S505), and the process proceeds to S506.

[0032] The control unit 58 judges whether or not the maintenance detection signal 103 at H level has been received and whether or not a predetermined time has elapsed since the start of the maintenance detection (S506). If the maintenance detection signal 103 at H level has not been received and the predetermined time has not elapsed (NO in S506), the control unit 58 returns the process to S506 and continues the maintenance detection until the maintenance detection signal 103 at H level is received or the predetermined time has elapsed. If the maintenance detection signal 103 at H level has been received or the predetermined time has elapsed without receiving the maintenance detection signal 103 at H level (YES in S506), the control unit 58 stores the maintenance detection result in the storage unit 59 (S507). If the maintenance detection signal 103 at H level has been received, the control unit 58 stores in the storage unit 59 as a maintenance detection result that the maintenance of the ionizer 46 is required. If the predetermined time has elapsed while the maintenance detection signal 103 is at L level, it indicates that the maintenance detection has been performed for the predetermined time. In this case, the control unit 58 stores in the storage unit 59 as a maintenance detection result that the maintenance of the ionizer 46 is not required.

[0033] The control unit 58 determines whether or not the information indicating that maintenance of the ionizer 46 is required is stored in the storage unit 59 based on the maintenance detection result (S508). If the information indicating that maintenance is required is stored in the storage unit 59 (YES in S508), the control unit 58 alternates between the H level and the L level of the LED control signal 105 to cause the LED 56 to blink (S509), prompting the user to clean the ionizer 46. The control unit 58 advances the process to S510. On the other hand, if the information indicating that maintenance is not required is stored in the storage unit 59 (NO in S508), the control unit 58 advances the process to S510.

[0034] The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S510). If a print job has been submitted (YES in S510), the image forming apparatus 100 starts the print job (S511) and ends the maintenance detection full control operation. If a print job has not been submitted (NO in S510), the maintenance detection full control operation ends.

[0035] FIG. 6 is a flowchart of the maintenance detection interruption control operation at the end of a print job. The control unit 58 executes the maintenance detection interruption control operation according to a program stored in the storage unit 59. When a print job is input to the image forming apparatus 100, the image forming apparatus 100 starts the print job (image forming operation) (S601). When the print job is started, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON (S602). The control unit 58 determines whether the sheet S on which an image has been formed has passed between the electrode needles 52a and 52b of the ionizer 46 (S603). If the sheet S has not passed through the ionizer 46 (NO in S603), the control unit 58 returns the process to S603 and waits for the sheet S to pass through the ionizer 46. When the sheet S passes through the ionizer 46 (YES in S603), the control unit 58 increments the count value of the sheet number counter 60 (S604).

[0036] Next, the control unit 58 determines whether the print job has ended (S605). If the print job has not ended (NO in S605), the control unit 58 returns the process to S603 and repeats the processes of S603 and S604. If the print job has ended (YES in S605), the control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (S606), and the process proceeds to S607.

[0037] The control unit 58 determines whether or not it has received an H-level maintenance detection signal 103 and whether or not a predetermined time has elapsed since the start of maintenance detection (S607). If it has received an H-level maintenance detection signal 103 or if the predetermined time has elapsed without receiving an H-level maintenance detection signal 103 (YES in S607), the control unit 58 stores the maintenance detection result in the storage unit 59 (S608).

[0038] The control unit 58 determines whether or not the information indicating that maintenance of the ionizer 46 is required is stored in the storage unit 59 based on the maintenance detection result (S609). If the information indicating that maintenance is required is stored in the storage unit 59 (YES in S609), the control unit 58 alternates between the H level and the L level of the LED control signal 105 to cause the LED 56 to blink (S610), prompting the user to clean the ionizer 46. The control unit 58 advances the process to S611. On the other hand, if the information indicating that maintenance is not required is stored in the storage unit 59 (NO in S609), the control unit 58 advances the process to S611.

[0039] The control unit 58 judges whether the count value of the number counter 60 has reached a predetermined number (S611). If the count value has reached the predetermined number (YES in S611), it is judged that maintenance detection (maintenance detection full control operation) performed at intervals of a predetermined number of sheets has been performed. The control unit 58 clears the count value of the number counter 60 to 0 (S612) and proceeds to the process of S613. If the count value of the number counter 60 has not reached the predetermined number (NO in S611), the control unit 58 proceeds to the process of S613 while maintaining the count value of the number counter 60.

[0040] The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S613). If a print job has been submitted (YES in S613), the image forming apparatus 100 starts the print job (S614), and the control unit 58 ends the maintenance detection interruption control operation. If a print job has not been submitted (NO in S613), the control unit 58 ends the maintenance detection interruption control operation.

[0041] In S607, if the H-level maintenance detection signal 103 has not been received and the predetermined time has not elapsed (maintenance detection in progress) (NO in S607), the control unit 58 advances the process to S615. The control unit 58 determines whether the count value of the sheet number counter 60 has reached a predetermined number (S615). The predetermined number may be set to, for example, the number of sheets that require maintenance. If the count value has reached the predetermined number (YES in S615), the control unit 58 returns the process to S607 and continues maintenance detection until the H-level maintenance detection signal 103 is received or the predetermined time has elapsed (maintenance detection full control operation).

[0042] If the count value of the sheet number counter 60 has not reached the predetermined number (NO in S615), the control unit 58 judges whether or not a print job has been submitted to the image forming apparatus 100 (S616). If a print job has not been submitted (NO in S616), the control unit 58 returns the process to S607 and continues the maintenance detection. If a print job has been submitted (YES in S616), the control unit 58 interrupts the maintenance detection (S617). The image forming apparatus 100 starts a print job (S618), and the control unit 58 ends the maintenance detection interruption control operation.

[0043] In this embodiment, if a print job is input during maintenance detection when the number of sheets neutralized by the ionizer 46 has not reached a predetermined number, the maintenance detection is interrupted. However, the maintenance detection interruption control operation is not limited to this. For example, the maintenance detection may be configured to be interrupted if a print job is input during maintenance detection when the accumulated time for neutralizing the sheets by the ionizer 46 has not reached a predetermined time.

[0044] With reference to Figs. 7 and 8, the timing of the maintenance detection of the ionizer 46 when the static eliminator 200 of this embodiment is powered on will be described. If the memory unit 59 stores that the ionizer 46 needs maintenance when the static eliminator 200 is powered on, the control unit 58 executes the maintenance detection (control to determine whether or not maintenance is necessary) again. The maintenance detection mode transition signal 102 is switched from L level to H level to start the maintenance detection. A maintenance detection full control operation in which the maintenance detection is continued until it is determined that the ionizer 46 needs maintenance within a predetermined time from the start of the maintenance detection or until a predetermined time has elapsed will be described with reference to Fig. 7. In addition, a maintenance detection interruption control operation in which the maintenance detection is interrupted when a print job is input during the maintenance detection will be described with reference to Fig. 8.

[0045] A user can select between the maintenance detection full control operation shown in Fig. 7 and the maintenance detection interruption control operation shown in Fig. 8, for example, from an operation unit 150 (Fig. 11) provided on the image forming apparatus 100 or the static electricity removal apparatus 200. In this embodiment, both the maintenance detection full control operation shown in Fig. 7 and the maintenance detection interruption control operation shown in Fig. 8 are used, but the present invention is not limited to this. The image forming system 300 may be configured to execute only one of the control operations.

[0046] 7 is a flowchart of the maintenance detection full control operation when the static eliminator 200 is powered on. The control unit 58 executes the maintenance detection full control operation according to a program stored in the storage unit 59. When the static eliminator 200 is powered on (YES in S701), the control unit 58 judges whether or not the information that the maintenance of the ionizer 46 is required is stored in the storage unit 59 (S702). This judgment is made based on the maintenance detection result, which is the previous judgment result stored in the storage unit 59 in S507 of FIG. 5 or S608 of FIG. 6, for example. When the information that the maintenance is not required is stored in the storage unit 59 (NO in S702), the control unit 58 ends the maintenance detection full control operation.

[0047] If the fact that maintenance is required is stored in the memory unit 59 (YES in S702), the control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to blink (S703). Next, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 on (S704). The control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (S705), and the process proceeds to S706.

[0048] The control unit 58 judges whether or not the maintenance detection signal 103 at H level has been received and whether or not a predetermined time has elapsed since the start of the maintenance detection (S706). If the maintenance detection signal 103 at H level has not been received and the predetermined time has not elapsed (NO in S706), the control unit 58 returns the process to S706 and continues the maintenance detection until the maintenance detection signal 103 at H level is received or the predetermined time has elapsed. If the maintenance detection signal 103 at H level has been received or the predetermined time has elapsed without receiving the maintenance detection signal 103 at H level (YES in S706), the control unit 58 stores the maintenance detection result in the storage unit 59 (S707). If the maintenance detection signal 103 at H level has been received, the control unit 58 stores in the storage unit 59 the fact that maintenance of the ionizer 46 is required as a maintenance detection result. If the maintenance detection signal 103 remains at L level for a predetermined time, the control unit 58 stores in the storage unit 59 the fact that maintenance of the ionizer 46 is not required as a maintenance detection result.

[0049] The control unit 58 determines whether or not the information that maintenance of the ionizer 46 is required is stored in the storage unit 59 (S708). If the information that maintenance is required is stored in the storage unit 59 (YES in S708), the control unit 58 advances the process to S712. On the other hand, if the information that maintenance is not required is stored in the storage unit 59 (NO in S708), this indicates that maintenance (cleaning) of the ionizer 46 has been performed. Therefore, the control unit 58 switches the LED control signal 105 to the L level to turn off the LED 56 (S710), and advances the process to S712.

[0050] The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S712). If a print job has been submitted (YES in S712), the image forming apparatus 100 starts the print job (S714) and ends the maintenance detection full control operation. If a print job has not been submitted (NO in S712), the maintenance detection full control operation ends.

[0051] 8 is a flowchart of the maintenance detection interruption control operation when the static eliminator 200 is powered on. The control unit 58 executes the maintenance detection interruption control operation according to a program stored in the storage unit 59. When the static eliminator 200 is powered on (S801), the control unit 58 judges whether or not the information that maintenance of the ionizer 46 is required is stored in the storage unit 59 (S802). This judgment is made based on the maintenance detection result, which is the previous judgment result stored in the storage unit 59 in S507 of FIG. 5 or S608 of FIG. 6, for example. When the information that maintenance is not required is stored in the storage unit 59 (NO in S802), the control unit 58 ends the maintenance detection interruption control operation.

[0052] If the fact that maintenance is required is stored in the memory unit 59 (YES in S802), the control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to blink (S803). Next, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON (S804). The control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (S805), and the process proceeds to S806.

[0053] The control unit 58 determines whether or not an H-level maintenance detection signal 103 has been received and whether or not a predetermined time has elapsed since the start of maintenance detection (S806). If an H-level maintenance detection signal 103 has been received or if the predetermined time has elapsed without receiving an H-level maintenance detection signal 103 (YES in S806), the control unit 58 stores the maintenance detection result in the storage unit 59 (S807).

[0054] The control unit 58 determines whether or not the information indicating that maintenance of the ionizer 46 is required is stored in the storage unit 59 based on the maintenance detection result (S808). If the information indicating that maintenance is required is stored in the storage unit 59 (YES in S808), the control unit 58 advances the process to S811. If the information indicating that maintenance is not required is stored in the storage unit 59 (NO in S808), this indicates that maintenance (cleaning) of the ionizer 46 has been performed. Therefore, the control unit 58 switches the LED control signal 105 to the L level to turn off the LED 56 (S810), and advances the process to S811.

[0055] The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S811). If a print job has been submitted (YES in S811), the image forming apparatus 100 starts the print job (S812) and ends the maintenance detection interruption control operation. If a print job has not been submitted (NO in S811), the maintenance detection interruption control operation ends.

[0056] In S806, if the H-level maintenance detection signal 103 has not been received and the predetermined time has not elapsed (maintenance detection in progress) (NO in S806), the control unit 58 advances the process to S813. The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S813). If a print job has not been submitted (NO in S813), the control unit 58 returns the process to S806 and continues the maintenance detection. If a print job has been submitted (YES in S813), the control unit 58 interrupts the maintenance detection (S814). The image forming apparatus 100 starts a print job (S815) and ends the maintenance detection interruption control operation.

[0057] 9 and 10, the timing of the maintenance detection of the ionizer 46 when the door 201 (FIG. 11) of the static eliminator 200 of this embodiment is opened and closed will be described. A user can open the door 201 of the static eliminator 200 to access the ionizer 46 and perform maintenance work on the ionizer 46. The opening and closing of the door 201 of the static eliminator 200 is detected by a door sensor 202 (FIG. 11) provided in the static eliminator 200. If the memory unit 59 stores information indicating that the ionizer 46 needs maintenance when the door 201 is opened and closed, the control unit 58 executes the maintenance detection (maintenance necessity determination control) again. The maintenance detection mode transition signal 102 is switched from L level to H level to start the maintenance detection. In the maintenance detection, it is determined whether the ionizer 46 needs maintenance. A maintenance detection full control operation in which maintenance detection is continued until it is determined that maintenance of the ionizer 46 is necessary within a predetermined time from the start of maintenance detection or until the predetermined time has elapsed will be described with reference to Fig. 9. Also, a maintenance detection interruption control operation in which maintenance detection is interrupted when a print job is input during maintenance detection will be described with reference to Fig. 10.

[0058] A user can select between the maintenance detection full control operation shown in Fig. 9 and the maintenance detection interruption control operation shown in Fig. 10 from, for example, an operation unit 150 (Fig. 11) provided on the image forming apparatus 100 or the static eliminator 200. In this embodiment, both the maintenance detection full control operation shown in Fig. 9 and the maintenance detection interruption control operation shown in Fig. 10 are used, but the present invention is not limited to this. The image forming system 300 may be configured to execute only one of the control operations.

[0059] FIG. 9 is a flowchart of the maintenance detection full control operation when the door of the static eliminator 200 is opened and closed. The control unit 58 executes the maintenance detection full control operation according to a program stored in the storage unit 59. When the door 201 of the static eliminator 200 is opened, the maintenance detection full control operation is started. The control unit 58 judges whether the door 201 is closed (S901). If the door 201 is open (NO in S901), the control unit 58 returns the process to S901 and waits for the door 201 to be closed. If the door 201 is closed (YES in S901), the control unit 58 judges whether the fact that the maintenance of the ionizer 46 is necessary is stored in the storage unit 59 (S902). This judgment is made based on the maintenance detection result, which is the previous judgment result stored in the storage unit 59 in S507 of FIG. 5 or S608 of FIG. 6. If the information that maintenance is not required is stored in the storage unit 59 (NO in S902), the control unit 58 ends the maintenance detection full control operation.

[0060] If the fact that maintenance is required is stored in the memory unit 59 (YES in S902), the control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to blink (S903). Next, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 on (S904). The control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (S905), and the process proceeds to S906.

[0061] The control unit 58 judges whether or not the maintenance detection signal 103 at H level has been received and whether or not a predetermined time has elapsed since the start of the maintenance detection (S906). If the maintenance detection signal 103 at H level has not been received and the predetermined time has not elapsed (NO in S906), the control unit 58 returns the process to S906 and continues the maintenance detection until the maintenance detection signal 103 at H level is received or the predetermined time has elapsed. If the maintenance detection signal 103 at H level has been received or the predetermined time has elapsed without receiving the maintenance detection signal 103 at H level (YES in S906), the control unit 58 stores the maintenance detection result in the storage unit 59 (S907). If the maintenance detection signal 103 at H level has been received, the control unit 58 stores in the storage unit 59 the fact that maintenance of the ionizer 46 is required as a maintenance detection result. If the maintenance detection signal 103 remains at L level for a predetermined time, the control unit 58 stores in the storage unit 59 the fact that maintenance of the ionizer 46 is not required as a maintenance detection result.

[0062] The control unit 58 determines whether or not the information that maintenance of the ionizer 46 is required is stored in the storage unit 59 (S908). If the information that maintenance is required is stored in the storage unit 59 (YES in S908), the control unit 58 advances the process to S910. On the other hand, if the information that maintenance is not required is stored in the storage unit 59 (NO in S908), this indicates that maintenance (cleaning) of the ionizer 46 has been performed. Therefore, the control unit 58 switches the LED control signal 105 to the L level to turn off the LED 56 (S909), and advances the process to S910.

[0063] The control unit 58 determines whether or not a print job has been input to the image forming apparatus 100 (S910). If a print job has been input (YES in S910), the image forming apparatus 100 starts the print job (S911) and ends the maintenance detection full control operation. If a print job has not been input (NO in S910), the control unit 58 transitions the state of the static eliminator 200 to a standby state (S912) and ends the maintenance detection full control operation.

[0064] FIG. 10 is a flowchart of the maintenance detection interruption control operation when the door of the static eliminator 200 is opened or closed. The control unit 58 executes the maintenance detection interruption control operation according to a program stored in the storage unit 59. When the door 201 of the static eliminator 200 is opened, the maintenance detection interruption control operation is started. The control unit 58 judges whether the door 201 is closed (S1001). If the door 201 is open (NO in S1001), the control unit 58 returns the process to S1001 and waits for the door 201 to be closed. If the door 201 is closed (YES in S1001), the control unit 58 judges whether the fact that the maintenance of the ionizer 46 is required is stored in the storage unit 59 (S1002). This judgment is made based on the maintenance detection result, which is the previous judgment result stored in the storage unit 59 in S507 of FIG. 5 or S608 of FIG. 6. If the information that maintenance is not required is stored in the storage unit 59 (NO in S1002), the control unit 58 ends the maintenance detection interruption control operation.

[0065] If the fact that maintenance is required is stored in the memory unit 59 (YES in S1002), the control unit 58 alternately switches the LED control signal 105 between H level and L level to cause the LED 56 to blink (S1003). Next, the control unit 58 switches the ionizer ON / OFF signal 101 from L level to H level to turn the ionizer 46 ON (S1004). The control unit 58 switches the maintenance detection mode transition signal 102 from L level to H level to start maintenance detection (S1005), and the process proceeds to S1006.

[0066] The control unit 58 determines whether or not it has received an H-level maintenance detection signal 103 and whether or not a predetermined time has elapsed since starting maintenance detection (S1006). If it has received an H-level maintenance detection signal 103 or if the predetermined time has elapsed without receiving an H-level maintenance detection signal 103 (YES in S1006), the control unit 58 stores the maintenance detection result in the storage unit 59 (S1007).

[0067] The control unit 58 determines whether or not the information indicating that maintenance of the ionizer 46 is required is stored in the storage unit 59 based on the maintenance detection result (S1008). If the information indicating that maintenance is required is stored in the storage unit 59 (YES in S1008), the control unit 58 advances the process to S1010. If the information indicating that maintenance is not required is stored in the storage unit 59 (NO in S1008), this indicates that maintenance (cleaning) of the ionizer 46 has been performed. Therefore, the control unit 58 switches the LED control signal 105 to the L level to turn off the LED 56 (S1009), and advances the process to S1010.

[0068] The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S1010). If a print job has been submitted (YES in S1010), the image forming apparatus 100 starts the print job (S1011) and ends the maintenance detection interruption control operation. If a print job has not been submitted (NO in S1010), the control unit 58 transitions the state of the static eliminator 200 to a standby state (S1012) and ends the maintenance detection interruption control operation.

[0069] In S1006, if the H-level maintenance detection signal 103 has not been received and the predetermined time has not elapsed (maintenance detection in progress) (NO in S1006), the control unit 58 advances the process to S1013. The control unit 58 determines whether or not a print job has been submitted to the image forming apparatus 100 (S1013). If a print job has not been submitted (NO in S1013), the control unit 58 returns the process to S1006 and continues the maintenance detection. If a print job has been submitted (YES in S1013), the control unit 58 interrupts the maintenance detection (S1014). The image forming apparatus 100 starts a print job (S1015) and ends the maintenance detection interruption control operation.

[0070] As described above, the control unit 58 executes the maintenance necessity determination control to determine whether or not maintenance of the ionizer 46 is necessary after the print job of the image forming apparatus 100 is completed. The control unit 58 also executes the maintenance necessity determination control when the power of the static eliminator 200 is turned on or when the door 201 of the static eliminator 200 is opened or closed. If a print job is input during the maintenance necessity determination control, the control unit 58 interrupts the maintenance necessity determination control and starts the print job. In this way, the control unit 58 executes the maintenance necessity determination control at an appropriate timing, thereby preventing a decrease in productivity due to the time required for the maintenance necessity determination control, and improving usability. [Explanation of symbols]

[0071] 46 Ionizer 56 LED 57...Frame body 57a...Top surface 57b...Front 58 Control section 100 Image forming apparatus 200... Static eliminator S...Seat

Claims

1. A static eliminator that eliminates static electricity from a sheet on which an image is formed by an image forming apparatus, a conveying means including a roller for receiving a sheet from the image forming apparatus and conveying the sheet; a non-contact type static elimination unit including an electrode portion and eliminating static electricity from the sheet conveyed by the conveyance unit in a non-contact state; a control unit that executes a maintenance necessity determination control to determine whether or not maintenance of the non-contact static eliminator is necessary; Equipped with The control unit stores a maintenance detection result of the maintenance necessity determination control in a storage unit, A static elimination device characterized in that, when the door of the static elimination device is opened or closed and the maintenance detection result stored in the memory unit indicates that maintenance of the non-contact static elimination means is required, the control unit executes the maintenance necessity determination control again.

2. Further comprising a sensor for detecting opening and closing of the door, When the door is in an open state, a user can access the non-contact static elimination means, 2. The static eliminator according to claim 1, wherein the control unit determines whether the door has been opened or closed based on the detection result of the sensor.

3. The de-ionization device described in Claim 1, further characterized in that it is provided with a display unit that displays information indicating that maintenance is required for the non-contact de-ionization means based on a predetermined signal output from the non-contact de-ionization means.

4. 4. The static eliminator according to claim 3, wherein the display unit is attached to an upper surface or a front surface of an exterior surface of the static eliminator.

5. The static elimination device according to claim 3, characterized in that the display unit displays the content in a first display pattern when maintenance is required for the non-contact static elimination means, and displays the content in a second display pattern when an abnormality occurs in the non-contact static elimination means.

6. the non-contact static elimination means comprises a first static elimination member including one of the electrode portions arranged to face a first surface of the sheet conveyed by the conveying means, and a second static elimination member including another of the electrode portions arranged to face a second surface of the sheet opposite to the first surface, 4. The static eliminator according to claim 3, wherein the display unit displays the maintenance information when maintenance is required for at least one of the first static eliminator and the second static eliminator.

7. the display unit is a light-emitting diode, the light-emitting diode is lit when the maintenance of the non-contact static eliminator is required; 4. The static eliminator according to claim 3, wherein the light emitting diode is turned off when the maintenance of the non-contact static eliminator is not required.

8. 8. The static eliminator according to claim 1, wherein the non-contact static eliminator is an ionizer that generates ions.

9. 8. The static elimination device according to claim 1, further comprising a contact static elimination means that is provided upstream of the non-contact static elimination means in the sheet transport direction and that eliminates static electricity from the sheet while in contact with the sheet.

10. the control unit determines that the maintenance of the non-contact static neutralization means is necessary when a predetermined signal is received during a predetermined time period from when the maintenance necessity determination control is started, 3. The static eliminator according to claim 1, wherein the control unit determines that the maintenance of the non-contact static eliminator is unnecessary if the predetermined signal is not received before the predetermined time has elapsed.

11. The control unit is configured to execute the maintenance necessity determination control after completion of a de-electrification operation in which the non-contact de-electrification means de-electrifies a plurality of sheets being continuously conveyed, 8. The static eliminator according to claim 1, wherein the control unit is configured not to execute the maintenance necessity determination control while the static elimination operation is being performed.

12. A de-ionization device as described in any one of claims 1 to 7, characterized in that the control unit is configured to execute the maintenance necessity judgment control to determine whether or not maintenance is necessary for the non-contact de-ionization means based on the fact that power is turned on to the de-ionization device.

13. The static elimination device according to any one of claims 1 to 7, characterized in that, when a print job is submitted during the maintenance necessity determination control, the control unit interrupts the maintenance necessity determination control and starts the print job.

14. A static eliminator for eliminating static electricity from a sheet on which an image is formed by an image forming apparatus, comprising: a conveying means including a roller for receiving a sheet from the image forming apparatus and conveying the sheet; a non-contact type static elimination unit including an electrode portion and eliminating static electricity from the sheet conveyed by the conveyance unit in a non-contact state; a control unit that executes a maintenance necessity determination control to determine whether or not maintenance of the non-contact static eliminator is necessary; Equipped with The control unit stores a maintenance detection result of the maintenance necessity determination control in a storage unit, A static elimination device characterized in that, when the power of the static elimination device is turned on and the maintenance detection result stored in the memory unit indicates that maintenance of the non-contact static elimination means is required, the control unit executes the maintenance necessity determination control again.

15. The de-ionization device described in Claim 14, further comprising a display unit that displays information indicating that maintenance is required for the non-contact de-ionization means based on a predetermined signal output from the non-contact de-ionization means.

16. The control unit is configured to execute the maintenance necessity determination control after completion of a de-electrification operation in which the non-contact de-electrification means de-electrifies a plurality of sheets being continuously conveyed, 16. The static eliminator according to claim 14, wherein the control unit is configured not to execute the maintenance necessity determination control while the static elimination operation is being performed.

17. an image forming apparatus for forming an image on a recording medium; a conveying means including a roller for receiving a sheet from the image forming apparatus and conveying the sheet; a non-contact type static elimination unit including an electrode portion and eliminating static electricity from the sheet conveyed by the conveyance unit in a non-contact state; a control unit that executes a maintenance necessity determination control to determine whether or not maintenance of the non-contact static eliminator is necessary; Equipped with The control unit stores a maintenance detection result of the maintenance necessity determination control in a storage unit, An image forming system characterized in that, when the door of the static elimination device is opened or closed and the maintenance detection result stored in the memory unit indicates that maintenance of the non-contact static elimination means is required, the control unit executes the maintenance necessity determination control again.

Images