JP2017053971A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that can release a state where an attachment door remains open and is not closed, and make a transition to a state where the attachment door is manually closed and developer can be supplied to a developing device.SOLUTION: An image forming apparatus 100 comprises: a toner container 618; an attachment part 628 to which the toner container is attached; an attachment door 616 that is opened when the toner container is taken out from the attachment part; a DC motor 604 that rotates the toner container 618 to supply a toner to a developing device; a latch lever 602 and a connection shaft 603 that urge a locking member 638 so as to shift an open state of the attachment door 616 to a closed state; the DC motor 604 that applies an urging force to the latch lever 602 and the like; and a control unit 200 that, when the attachment door 616 is closed and the latch lever 602 and the like apply the urging force to the locking member 638, drives the DC motor 604 to release the state of urging by the latch lever 602 and the like.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an image forming apparatus capable of replacing a developer container for supplying developer to a developing device.

  In recent years, in an image forming apparatus, in order to ensure user convenience, it is required to shorten the replacement work time of consumables. Examples of consumables that can be replaced include a sheet, a toner container, and a collected toner container (Patent Document 1). For example, when toner is supplied to the image forming apparatus, toner is supplied from a storage container in which toner is stored according to the amount of toner consumed in the output image.

  In general, a door is provided at a mounting portion to which the storage container is mounted so that the user does not touch the storage container while toner is supplied from the storage container. When the toner in the storage container becomes less than a predetermined amount, the door of the mounting unit is opened to replace the storage container.

JP 2011-227354 A

  However, in an image forming apparatus that replenishes toner from a storage container, an open / close mechanism for opening the door after opening the door to replace the storage container may prohibit the door from closing. It was.

  An object of the present invention is to prevent the door of the mounting unit from being closed after the storage container is mounted to the mounting unit.

  In order to solve the above-described problem, the image forming apparatus according to claim 1 includes a latent image forming unit that forms an electrostatic latent image on a photoconductor and a storage unit that stores toner, and the toner in the storage unit. Developing means for forming the image by developing the electrostatic latent image using a toner, a mounting portion to which a storage container storing toner to be supplied to the storage portion is mounted, and a mounting portion provided in the mounting portion. A door that is opened to take out the storage container from the part, and a rotational drive in the first direction to rotate the storage container mounted on the mounting part in a second direction different from the first direction. Drive means for opening the door by rotational driving, control means for controlling the drive means, first detection means for detecting that the door is open, and the drive means in the second direction And the driving means And a second detecting means for detecting the phase of the driving means, and the control means includes the first detecting means for prohibiting the door from being closed when the phase reaches a predetermined phase. When the door detects that the door is opened and the phase of the drive means is the predetermined phase based on the detection result of the second detection means, the phase of the drive means is the predetermined phase. The drive means is rotationally driven in the second direction so as not to become.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that it will be in the state which does not close the door of a mounting part after mounting | wearing a storage container with a mounting part.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment. FIG. 2 is a cross-sectional view of a toner replenishing device that replenishes toner to a developing device of the image forming apparatus of FIG. 1. FIG. 3 is a perspective view of a toner container. FIG. 2 is a block diagram illustrating a control configuration of the image forming apparatus in FIG. 1. 2 is a flowchart illustrating a procedure of printing processing executed by the image forming apparatus in FIG. 1. 2 is a flowchart illustrating a procedure of toner remaining amount detection processing of a toner container that is executed in the image forming apparatus of FIG. 1. 3 is a flowchart showing a procedure of recovery processing executed by the image forming apparatus of FIG. 1. It is a figure for demonstrating the door opening / closing mechanism in a toner supply apparatus, and is a figure which shows the state which the door closed. It is a figure for demonstrating the door opening / closing mechanism in a toner supply apparatus, and is a figure which shows a locked state. It is a timing chart of door opening and closing operation. It is a timing chart for making it transfer from a non-closeable state of a door in a recovery process to a closeable state.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment.

  In FIG. 1, an image forming apparatus 100 is a full color printer. The image forming apparatus 100 includes an image forming unit, a transfer unit, a paper storage unit, and a transport unit that transports a sheet stored in the paper storage unit to the transfer unit.

  The image forming unit includes a plurality of image forming stations 1a, 1b, 1c, and 1d arranged in the horizontal direction. The image forming stations 1a to 1d have the same configuration. The image forming station 1a forms a yellow toner image. The image forming station 1b forms a magenta toner image. The image forming station 1c forms a cyan toner image. Then, the image forming station 1d forms a black toner image.

  Each of the image forming stations 1a to d includes photosensitive drums 10a to 10d, and charging rollers 41a to 41d, developing devices 51a to 51d, and primary transfer rollers 2a to 2d are arranged around the photosensitive drums 10a to 10d, respectively. Has been. The exposure device 6 exposes the photosensitive drums 10a to 10d based on image data transferred from an external device such as a PC or a scanner, and forms latent images of the respective colors on the photosensitive drums 10a to 10d.

  For example, the photosensitive drums 10a to 10d as the photosensitive members are formed by forming a negatively charged photosensitive layer on the outer peripheral surface of an aluminum cylinder, and are driven to rotate based on the process speed. The charging rollers 41a to 41d are applied with a superimposed voltage obtained by superimposing an alternating voltage on a direct current voltage, and charge the surfaces of the photosensitive drums 10a to 10d to a predetermined potential.

  The exposure apparatus 6 has a light source corresponding to the image forming stations 1a, 1b, 1c, and 1d, and the light source emits a laser beam based on the image data. The laser beam emitted from the light source scans the surface of the photosensitive drums 10a to 10d by a rotating mirror. Thereby, electrostatic latent images corresponding to the respective colors are formed on the photosensitive drums 10a to 10d. For example, the developing devices 51a to 51d stir a two-component developer containing toner (non-magnetic material) and a carrier (magnetic material) to charge the toner, and supply the charged toner to the photosensitive drums 10a to 10d. The electrostatic latent images on the photosensitive drums 10a to 10d are developed.

  The primary transfer rollers 2a to 2d press inner surfaces of an intermediate transfer belt 3 described later to form primary transfer portions Ta to d between the photosensitive drums 10a to 10d and the intermediate transfer belt 3, respectively. By applying a positive DC voltage to the primary transfer rollers 2a to 2d, the negative toner images carried on the photosensitive drums 10a to 10d are transferred to the intermediate transfer belt 3 in the primary transfer portions Ta to d. A full color image is formed on the intermediate transfer bell 3 by transferring the images formed at the image forming stations 1 a to 1 d in a superimposed manner. The image forming stations 1a to 1d are exchange units (process cartridges) that are detachably provided in the image forming apparatus 100.

  An intermediate transfer belt 3 that rotates so as to be in sliding contact with the photosensitive drums 10a to 10d of the image forming stations 1a to 1d is disposed in the transfer unit on the upper side of the image forming unit. The toner images carried on the photosensitive drums 1a to 1d are transferred to the intermediate transfer belt 3 to form a color image. The intermediate transfer belt 3 functions as an intermediate transfer member to which a toner image is transferred.

  The intermediate transfer belt 3 is composed of an endless belt member, and is supported by being stretched over a tension roller 27, a belt driving roller 26, a secondary transfer inner roller 25, primary transfer stretching rollers 28 and 29, and the like. ing. The intermediate transfer belt 3 is driven by a belt driving roller 26 and rotates in the direction of arrow R2 in FIG. A density detection sensor 80 for detecting the density of the toner image on the intermediate transfer belt 3 is provided so as to face the rotating intermediate transfer belt 3. The density detection sensor 8 is an optical sensor, for example.

  Further, a secondary transfer outer roller 22 is disposed so as to face the secondary transfer inner roller 25. The secondary transfer outer roller 22 abuts on the intermediate transfer belt 3 whose inner surface is stretched by the secondary transfer inner roller 25 connected to the ground to form a secondary transfer portion T2. A toner image carried on the intermediate transfer belt 3 is transferred to the sheet P by applying a positive DC voltage to the secondary transfer outer roller 22. The intermediate transfer unit 20 including the intermediate transfer belt 3 and its support mechanism and drive mechanism is an exchange unit that can be attached to and detached from the main body 30 of the image forming apparatus 100 in an integrated manner.

  The sheet storage unit is disposed at the bottom of the image forming apparatus 100. The paper storage unit includes a paper cassette 4 in which the sheet P is stored.

  The image forming apparatus 100 is provided with a conveyance section from the sheet storage section to the secondary transfer section T2, the fixing apparatus 5 described later, and the sheet discharge roller 11 to the sheet discharge tray 7. The conveyance unit includes a separation roller 8, a registration roller 9, and a paper discharge roller 11 along the conveyance direction of the sheet P. The transport unit transports the sheet P stored in the paper cassette 4 to the paper discharge tray 7 through the secondary transfer unit T <b> 2 and the fixing device 5.

  The fixing device 5 includes a heating member 5a having a heater and a pressure member 5b that presses the heating member 5a. The image forming apparatus 100 passes the sheet P between the heating member 5a and the pressing member 5b. The fixing device melts the toner image and fixes the toner image on the sheet P by the heat of the heater and the pressure of the heating member 5a and the pressure member 5b. The sheet P on which the toner image is fixed in the fixing device 5 is discharged to the discharge tray 7 by the discharge roller 11.

  Next, a toner replenishing device that replenishes toner to the developing devices 51 (a to d) of the image forming apparatus 100 will be described. The toner replenishing device in each image station has the same configuration. Hereinafter, a toner replenishing device that replenishes toner to the developing device 51a of the image forming apparatus 100 will be described.

  2 is a cross-sectional view of a toner replenishing device that replenishes toner to the developing device 51 of the image forming apparatus 100 of FIG.

  In FIG. 2, the toner replenishing device 600 includes a cylindrical mounting portion 628 to which the toner container 618 is mounted, a hopper portion 625 connected to the mounting portion 628, and a screw 647 disposed at the bottom of the hopper portion 625. Is mainly composed of FIG. 2 shows a state where the toner container 618 is mounted at a predetermined position of the mounting portion 628. When the toner container 618 is driven to rotate at a predetermined position, the toner falls from the toner container 618 to the hopper 625. As a result, toner is supplied from the toner container 618 to the hopper 625. The hopper unit 625 functions as a buffer unit that temporarily stores the developer (toner) supplied from the toner container 618 to the developing device 51.

  The mounting portion 628 is provided with a door 616 that opens and closes for the user to replace the toner container 618. By opening and closing the door 616, the toner container can be attached to and removed from the attachment portion 628. The toner container 618 is rotationally driven with the door 616 closed so that the user does not touch the rotating toner container 618 when the toner supply operation is performed.

  A piezo sensor 641 is disposed at a predetermined height on the side wall of the hopper 625. The piezo sensor 641 detects the presence or absence of toner at a predetermined height of the hopper unit 625. Therefore, based on the detection value of the piezo sensor 641, it is detected whether the amount of toner in the hopper 625 is equal to or greater than a certain amount. The hopper 625 is connected to the developing device 51 via a discharge port 627 provided at one end of the bottom where the screw 647 is disposed. A screw 647 serving as a toner conveying unit replenishes the toner in the hopper 625 to the developing device 51 through the discharge port 627.

  The toner replenishing device 600 replenishes toner to the developing device 51 from the toner container 618 via the hopper unit 625 based on the amount of toner consumed by the developing device 51.

  Next, a toner container mounted on the mounting portion 628 of the toner supply device will be described.

  FIG. 3 is a perspective view of the toner container 618. In FIG. 3, the toner container 618 is a cylindrical container, and a spiral groove 622 is formed. A spiral groove is also formed on the inner peripheral surface of the toner container 618. Accordingly, the toner in the toner container 618 is conveyed toward the discharge port 624 by rotating the toner container 618. Furthermore, a gear groove 623 is provided along the circumferential direction on the outer peripheral surface of the toner container 618. The toner container 618 rotates when a driving force is supplied through the gear groove 623.

  Next, the control configuration of the image forming apparatus 100 will be described.

  FIG. 4 is a block diagram showing a control configuration of the image forming apparatus of FIG.

  In the image forming apparatus 100, a DC load such as a motor and a clutch / solenoid, and sensors such as a photo interrupter and a micro switch are arranged at various locations inside the apparatus. The image forming apparatus 100 drives a transfer material and drives each unit by appropriately driving a motor and each DC load, and the operation is monitored by various sensors.

  In FIG. 4, the image forming apparatus 100 includes a control unit 200. The control unit 200 comprehensively controls the entire image forming apparatus 100 and exchanges data with the user via a user interface, including driving of each load, information collection analysis of sensors, and image control.

  The control unit 200 includes a CPU 201a, a ROM 201b, and a RAM 201c. The control unit 200 is connected to the control unit 202, the A / D converter 203, the high voltage control unit 205, the motor control unit 207, the DC load control unit 208, the sensor IF 209, the AC driver 210, and the image control unit 220. .

  The CPU 201a controls the entire image forming apparatus according to a program stored in the ROM 201b. The ROM 201b stores various programs executed by the CPU 201a. The RAM 201c is a system work memory. The RAM 201c stores, for example, a high voltage set value set in the high voltage control unit 205, various data described later, image formation command information from the operation unit 202, and the like. The RAM 201c includes a battery (not shown), and can retain data even when the image forming apparatus 100 is powered off.

  The operation unit 202 obtains information such as a copy magnification and a density setting value from the user, and, for example, information on the number of formed images, information on whether or not an image is being formed, occurrence of a jam, occurrence location, and the like. It functions as an informing part for informing.

  The A / D converter 203 converts the resistance value change of the thermistor 204 according to the temperature change of the fixing roller into a voltage value, and then inputs the voltage value to the CPU 201a.

  The high voltage control unit 205 inputs various high voltage control signals to a high voltage unit 206 including a development high voltage circuit 32, a charging high voltage circuit 33, a primary transfer high voltage circuit 34, and a secondary transfer high voltage circuit 35. The high pressure unit 206 applies an appropriate high pressure to the charging roller 41, the developing roller in the developing device 51, the primary transfer roller 2, and the secondary transfer inner roller 25.

  The motor control unit 207 includes a toner unit driving circuit 504 and controls each motor 212 including the DC motor 604 based on signals from the sensors 214.

  The DC load control unit 208 controls the clutch / solenoid 213.

  The sensor IF 209 has a sensor IF 506. The sensor IF 209 receives signals from sensors 214 such as a door opening / closing sensor 620, a phase sensor 614, a toner container rotation sensor 642, and a piezo sensor 641.

  The AC driver 210 controls ON / OFF of the heater 5a built in the fixing roller 5a based on the temperature measured by the thermistor 204 provided in the fixing roller 5a of the fixing device 5.

  The image control unit 220 performs predetermined image processing on image data input from the outside.

  Hereinafter, a printing process executed by the image forming apparatus 100 in FIG. 1 will be described.

  FIG. 5 is a flowchart showing the procedure of the printing process executed by the image forming apparatus 100 of FIG. This print processing is executed by the CPU 201a of the control unit 200 according to a print processing program stored in the ROM 201b.

  In FIG. 5, when the printing process is started, the CPU 201a confirms that the power of the main body of the image forming apparatus 100 is turned on by the user or a serviceman or that the main body of the image forming apparatus 100 returns from the sleep state (Step S1). S701).

  Next, the CPU 201a issues a command to the high voltage control unit 205, the motor control unit 207, the DC load control unit 208, the sensor IF 209, the AC driver 210, the image control unit 220, and the like, and performs adjustment operations such as image writing position and density adjustment. Execute (Step S702).

  After the adjustment operation is completed, the CPU 201a determines whether a print job has been received (step S703). The print job corresponds to input information including image data corresponding to an image for at least one page and information on the paper type and size of the sheet on which the image is to be formed. If the result of determination in step S703 is that a print job has been received (“YES” in step S703), the CPU 201a sends an instruction to each control unit to start image forming processing according to the job content (step S704). As a result, the image forming apparatus 100 forms an image based on the image data on the sheet P. Next, the CPU 201a determines whether or not the print job is finished, and executes image forming processing until the print job is finished (step S705). If the result of determination in step S705 is that the print job has been completed (“YES” in step S705), the CPU 201a ends the printing process (step S706).

  On the other hand, if the result of determination in step S703 is that a print job has not been received (“NO” in step S703), the CPU 201a ends this processing as it is.

  According to the process of FIG. 5, after the adjustment process is performed (step S702), the print job is received (step S703), and the print process is started (step S704), the image forming process can be executed satisfactorily. .

  Next, a toner remaining amount detection process of the toner container 618 executed by the image forming apparatus 100 in FIG. 1 will be described.

  FIG. 6 is a flowchart illustrating the procedure of the toner remaining amount detection process of the toner container 618 executed by the image forming apparatus 100 of FIG. The toner remaining amount detection processing of the toner container 618 is executed by the CPU 201a of the control unit 200 according to the toner remaining amount detection processing program stored in the ROM 201b. The toner remaining amount detection processing of the toner container 618 is executed in parallel with the replenishment operation of replenishing toner from the toner container 618 to the hopper unit 625 when the amount of toner in the hopper unit 625 is smaller than a predetermined amount by the piezo sensor 641. Is done.

  In FIG. 6, toner remaining amount detection processing (hereinafter simply referred to as “toner remaining amount detection processing”) in the toner container is performed, for example, when a predetermined amount or more of toner is not accumulated in the hopper unit 625 and Executed when the container 618 is replaced. First, the CPU 201a initializes the rotation number C of the toner container 618 (step S801). Next, the CPU 201a determines whether or not the piezo sensor 641 is ON (step S802). When the amount of toner in the hopper 625 detected by the piezo sensor 641 is equal to or greater than a predetermined amount, the piezo sensor 641 outputs a signal indicating an ON state. If the result of determination in step S802 is that the piezo sensor 641 is ON (“YES” in step S802), the CPU 201a advances the processing to step S803, that is, the CPU 201a determines the current rotation speed of the toner container 618 from the RAM 201c. The count value C to be detected is read in. The CPU 201a reads a threshold value that is a predetermined count value from the ROM 201b, and determines whether or not the current count value C at the time of developer replenishment is larger than the predetermined count value.

  As a result of the determination in step S803, if the current count value C is larger than the predetermined count value (“YES” in step S803), the CPU 201a advances the process to step S804. That is, the CPU 201a displays a message for prompting the user to replace the toner container 618 on the screen of the operation unit 202 (step S804). The monitor of the operation unit 202 may be configured to display a soft switch for allowing the user to select whether or not to perform the opening operation of the door 616. In this configuration, the door 616 is unlocked when the user presses the soft switch.

  Next, the CPU 201a executes an auxiliary operation for replacing the toner container 618 (step S805), and then detects the remaining amount of toner (step S806). In step S <b> 806, the remaining amount of toner in the toner container 618 is calculated based on the count value of how many times the motor 604 has been rotated in the toner supply operation after the toner container 618 has been replaced. Since the toner replenishment amount for one rotation of the toner container is determined in advance, the toner replenishment amount per rotation is multiplied by the count value of the rotation of the toner, so that the toner container 618 is directed to the image forming apparatus. The amount of discharged toner (W1) is obtained. Therefore, by subtracting the replenished toner amount (W1) from the initial charged toner amount (W0) in the toner container 618, the remaining amount of toner in the toner container 618 is obtained.

  As a result of the determination in step S803, if the count value C is larger than the threshold value indicating that the remaining amount of toner in the toner container 618 has approached “0”, the remaining amount of toner is close to “0”, and the toner container 618 has reached. It is considered that it is time to replace

  Next, the CPU 201a determines the remaining amount of toner in the toner container 618, and then ends this process. Note that after the present process is completed, the user or service person replaces the toner container 618 as necessary.

  On the other hand, if the result of the determination in step S803 is that the current count value C is not greater than the predetermined threshold (“NO” in step S803), the CPU 201a determines the remaining amount of toner in the toner container 618 based on the count value C. It is calculated (step S806). After obtaining the remaining amount of toner in the toner container 618, the CPU 201a ends this processing in the same manner as described above.

  If the result of determination in step S802 is that the piezo sensor 641 is not ON, the CPU 201a advances the processing to step S807. That is, the CPU 201a drives the DC motor 604 that drives the toner container 618 clockwise (step S807). Next, the CPU 201a determines whether or not the toner container rotation sensor that detects the rotation of the toner container is ON (step S808). The configuration of the toner container rotation sensor will be described in detail later.

  If the result of the determination in step S807 is that the toner container rotation sensor 642 is ON (“YES” in step S807), the CPU 201a reads the current count value C from the RAM 201b and increments and updates it (step S809). Next, the CPU 201a returns the process to step S802, determines again whether the piezo sensor 641 is ON (step S802), and repeats steps S807 to S809 and S802 until the piezo sensor 641 is turned ON.

  On the other hand, as a result of the determination in step S808, also when the toner container rotation sensor 642 is not ON (“NO” in step S808), the CPU 201a returns the process to step S802 as described above, and whether the piezo sensor 641 is ON again. Judging.

  According to the processing in FIG. 6, the remaining amount of toner in the toner container 618 is obtained based on the rotation count value C of the toner container 618 (step S806). When the count value C of rotation of the toner container 618 exceeds a predetermined threshold (step S803), a display for prompting the user to replace the toner container 618 is performed (step S804). Accordingly, the remaining amount of toner in the toner container can be accurately grasped, and the user can replace the toner container 618 before the toner container 618 is emptied.

  Next, a description will be given of a method for the user or service person to escape from the mechanically latched locked state that easily falls during the toner container replacement operation. The locked state is a prohibited state that prohibits the door from being closed. The process for shifting the door 616 that is in the locked state and is not closed while being opened is referred to as a recovery process.

  FIG. 7 is a flowchart showing a procedure of recovery processing executed by the image forming apparatus 100 of FIG. This recovery process is executed by the CPU 201a of the control unit 200 according to a recovery program stored in the ROM 201b.

  In FIG. 7, when the recovery process is started, the CPU 201a reads the output of the door opening / closing sensor 620 via the sensor IF 209 and determines whether or not the door opening / closing sensor 620 is ON (step S901). If the door opening / closing sensor 620 is ON, the door 616 is in an open state that is mechanically opened.

  Here, a door opening / closing mechanism in the toner replenishing device 600 will be described. 8A and 8B are views for explaining a door opening / closing mechanism in the toner replenishing device. FIG. 8A is a diagram illustrating a state in which the door 616 is closed. FIG. 8B is a diagram showing a locked state in which the door 616 is opened.

  The door opening / closing mechanism includes a DC motor 604 as a drive source, a gear 601 with a boss, a latch lever 602, a transmission gear 643, and a transmission gear 644. Further, the door opening / closing mechanism is provided with a claw release lever 638 having a restricting portion 638a that restricts the door 616 from being opened.

  A gear 636 is fixed to the rotation shaft 632 of the gear 601 with a boss. The gear 636 transmits the rotational driving force of the DC motor 604 to a gear groove 623 provided on the outer peripheral surface of the toner container 618. When the DC motor 604 rotates clockwise (forward rotation), the bossed gear 601 rotates idly. On the other hand, when the DC motor 604 rotates (reverses) counterclockwise, the bossed gear 601 rotates.

  The latch lever 602 can swing around the fulcrum 602b. The claw release lever 638 can rotate around a fulcrum 638b. Furthermore, a connecting shaft 603 that connects the latch lever 602 and the claw release lever 638 is disposed in the door opening / closing mechanism. As the boss-equipped gear 601 rotates, the boss of the boss-equipped gear 601 contacts the boss of the latch lever 602. The latch lever 602 is pushed by the boss gear 601 and the latch lever 602 swings around the fulcrum 602b. Then, the connecting shaft 603 presses a part of the claw release lever 638. Accordingly, when the claw release lever 638 rotates about the fulcrum 638b in the counterclockwise direction in the figure, the restricting portion 638a of the claw release lever 638 is separated from the claw of the door 616. Then, the door 616 is opened and the open state is maintained.

  The phase sensor 614 is an optical sensor having a light emitting unit and a light receiving unit. The phase sensor 614 detects that the latch lever 602 has moved from a predetermined phase, for example, from the first phase to the second phase. The first phase corresponds to the rotation phase (swing angle) of the latch lever 602 when the claw release lever 638 restricts the door 616. The second phase corresponds to the rotation phase (swing angle) of the latch lever 602 when the claw release lever 638 opens the door 616. When the latch lever 602 is in the first phase, a part of the latch lever 602 blocks the optical path of the phase sensor 614. Since the light receiving unit cannot receive light, the phase sensor 614 outputs a low level signal. On the other hand, when the latch lever 602 is in the second phase, a part of the latch lever 602 is retracted from the phase sensor 614. Therefore, in the phase sensor 614, the light receiving unit receives the light emitted from the light emitting unit. Since the light receiving unit receives light, the phase sensor 614 outputs a high level signal. The phase sensor 614 is a sensor including a light emitting unit and a light receiving unit. The phase sensor 614 changes the output signal when the latch lever 602 swings and the convex portion 602a moves. That is, when the opening of the door 616 shown in FIG. 8A is restricted, the convex portion 602a shields the light irradiated from the light emitting portion to the light receiving portion. Therefore, the phase sensor 614 outputs a low level signal indicating the shielding state. On the other hand, when the door 616 shown in FIG. 8B is opened, the convex portion 602a is not between the light emitting portion and the light receiving portion. Therefore, the phase sensor 614 outputs a high level signal indicating the transmission state.

  The door opening / closing mechanism includes a toner container rotation sensor 642 and a sensor flag 645 that contacts a part of the toner container 618 in order to detect the rotation phase of the toner container 618. A concave portion 646 is provided at one place on the outer peripheral portion of the toner container 618 on the discharge port side. While the toner container 618 is driven to rotate, the sensor flag 645 continues to contact the toner container 618. While the sensor flag 645 is in contact with the recess 646, the sensor flag 645 moves to the detection position of the toner container rotation sensor 642. On the other hand, while the sensor flag 645 is in contact with a position other than the recess 646, the sensor flag 645 moves to a position different from the detection position of the toner container rotation sensor 642.

  The toner container rotation sensor 642 is, for example, a photo interrupter, and whether the sensor flag 645 is in the detection position while the toner container 618 rotates and the sensor flag 645 is in contact with the recess 646 provided on the outer periphery. Is detected. Thus, it is possible to detect that the toner container 618 has made one rotation based on the change in the sensor output (detection result) of the toner container rotation sensor 642.

  8A and 8B, the DC motor 604 is a drive source of the toner replenishing device 600. When the DC motor 604 rotates clockwise (forward rotation), the gear 643 rotates and the toner container 618 is driven to rotate. That is, when the DC motor 604 rotates clockwise, the driving torque of the DC motor 604 is transmitted to the boss gear 601 via the gears 643 and 644, and the boss gear 601 rotates. When the boss-equipped gear 601 rotates, the boss of the boss-equipped gear 601 comes into contact with the boss of the latch lever 602, and the rotation of the boss-equipped gear 601 stops.

  When a predetermined torque is applied to the gear 601 with the boss and the rotating shaft 632 rotates, the driving torque is transmitted to the gear 636. As a result, the toner container 618 is driven to rotate. When the toner remains in the toner container 618, the toner container 618 rotates, whereby the toner in the toner container 618 is discharged from the discharge port and replenished to the developing device 51.

  The toner replenishing device 600 replenishes the developing device 51 with the toner in the hopper unit 625 according to the toner consumption amount in the developing device 51. At this time, based on the output value of the piezo sensor 641, the toner is discharged from the toner container 618 to the hopper unit 625 so that the toner amount in the hopper unit 625 becomes a predetermined amount or more. As a result, the amount of toner in the toner container 618 decreases.

  The detection of the toner amount in the toner container 618 is calculated based on the amount of rotation (number of rotations) of the toner container 618 when toner is supplied to the developing device 51. In the toner replenishing device 600, the toner discharge amount from the toner discharge port 624 is obtained in advance during one rotation of the toner container 618, and the toner discharge amount is calculated based on the rotation amount (number of rotations). The remaining amount of toner 618 is calculated.

  Then, when the remaining amount of toner in the toner container 618 falls below a predetermined amount, a message prompting replacement of the toner container 618 is displayed on the monitor of the operation unit 202. The replacement timing of the toner container 618 is determined based on the number of rotations (number of rotations) of the toner container. The rotation amount (number of rotations) of the toner container 618 is measured using a toner container rotation sensor 642.

  Specifically, when the piezo sensor 641 detects that the amount of toner in the hopper unit 625 is less than a predetermined amount, the toner container 618 is rotated to discharge the toner from the toner container 618 to the hopper unit 625. Then, the toner container 618 is rotationally driven until it is detected by the piezo sensor 641 that the amount of toner in the hopper 625 is greater than or equal to a predetermined amount.

  Then, when the remaining amount of toner in the toner container 618 becomes a predetermined amount or less, for example, a message “Please replace the toner container” is displayed on the monitor of the operation unit 202. When this message is displayed, for example, the user or service person replaces the toner container 618 in accordance with the guidance output to the monitor of the operation unit 202.

  When replacing the toner container 618, the user or service person operates the operation unit 202 to open the door 616 of the toner container mounting unit 628 in order to take out the toner container 618. After the door 616 is opened, the user or service person takes out the used toner container 618, installs a new toner container 618, and then closes the door 616 by hand to complete the replacement operation.

  Whether the door 616 is in a closed state is detected by a door open / close detection sensor 620. The door opening / closing detection sensor 620 is, for example, a push switch. When the door 616 is closed, the push switch is pressed, so that it is detected that the door 616 is closed. On the other hand, when the door 616 is opened, the push switch is released from the pressed state, so that it is detected that the door 616 is opened.

  Next, the operation of the door opening / closing mechanism will be described.

  In the door opening / closing mechanism, when the door 616 shown in FIG. 8A is closed, the DC motor 604 rotates (reverses) counterclockwise, so that the door 616 is opened as shown in FIG. 8B.

  That is, in FIG. 8A, when the DC motor 604 is reversed, the gear 601 with the boss rotates, and the boss of the gear 601 with the boss presses the boss of the latch lever 602. When the boss of the latch lever 602 is pushed, the latch lever 602 swings around the fulcrum 602b, and pushes the connecting shaft 603 rightward in FIG. 8A. As a result, the connecting shaft 603 pushes the lower part of the claw release lever 638. The claw release lever 638 swings around the fulcrum 638b. By the swinging of the claw release lever 638, the restricting portion 638a of the claw release lever 638 and the claw 640 of the door 616 are separated and the door 616 is opened. The latch lever 602 and the claw release lever 638 are swing members.

  At this time, the lower end of the latch lever 602 swings in the right direction in FIG. 8B, and the convex portion 602 a retracts from the detection position of the phase sensor 614. The phase sensor 614 detects that the door 616 is opened by retracting the convex portion 602a of the latch lever 602.

  Next, a timing chart of the door opening / closing operation will be described.

  FIG. 9 is a timing chart of the door opening / closing operation.

  The door 616 is configured to open when the DC motor 604 rotates (reverses) in the second direction. In the description of FIG. 9, focusing on the opening operation of the DC motor 604, the reverse rotation of the DC motor is referred to as turning on the DC motor, and the stopping of the DC motor is referred to as turning off.

  Hereinafter, ON / OFF of DC motor 604, presence / absence of swing operation of latch lever 602, phase sensor 614 ON (transmission) / OFF (shielding), opening / closing door 616, non-closing state of door 616 / closed The door opening / closing operation will be described using possible states.

  In FIG. 9, when the DC motor 604 is turned on and rotated counterclockwise, the bossed gear 601 rotates, and the boss position of the bossed gear 601 reaches the latch lever 602 and contacts the latch lever 602. At this time, the boss of the bossed gear 601 in contact with the latch lever 602 urges the latch lever 602, and the latch lever 602 swings to change from non-operation to operation (710). When the latch lever 602 changes from non-operation to operation, the projection 602a of the latch lever 602 is removed, and the phase sensor 614 changes from the shield state to the transmission state (712).

  As the latch lever 602 changes from non-operating to operating, the connecting shaft 603 is pushed in the direction of the door 616. When the connecting shaft 60 is pushed in the direction of the door 616, the locking state of the claw 640 of the door 616 by the restricting portion 638a of the claw release lever 638 is released, and the claw 640 is changed from the closed state to the open state. As a result, the door 616 is moved from a closed state (state shown in FIG. 8A) to an open state, that is, a non-closeable state (state shown in FIG. 8B) by a spring (not shown) provided on the door 616. (716).

  In such a door opening / closing operation, if the phase sensor 614 is in the shielding state, the latch lever 602 does not swing, and the connecting shaft 603 is pushed in and the restricting portion 638a of the claw release lever 638 is opened. There is no. Therefore, the user or the service person can close the door 616 by hand.

  On the other hand, from the time point 712 when the phase sensor 614 changes from the shielded state to the transmissive state, until the time point 716 when the transmissive state is released to return to the shielded state and the claw 640 of the door 616 is locked, the claw release lever 638 is clawed. 640 is in the open locked state. Therefore, the user or service person cannot close the door 616 by hand. When the DC motor 604 further rotates, the boss-equipped gear 601 makes one rotation, the latch lever 602 swings again by the boss-equipped gear 601, and the phase sensor 614 enters the transmission state.

  That is, the locked state in which the user or service person cannot close the door 616 manually is when the user or the like replaces the toner container 618 by rotating the toner container 618 counterclockwise the output shaft of the DC motor 604. It can happen easily by turning to.

  In a gear configuration in which the toner replenishment operation and the door 616 opening operation are performed by forward and reverse rotation of the DC motor 604, the toner container 618 is manually rotated counterclockwise, whereby the bossed gear 601 is moved from the toner container 618 through the gear 636. The counterclockwise rotational torque is transmitted to. As a result, the door 616 is moved to the opening operation, and the phase sensor 614 is changed from the shield state to the transmission state. In this case, the user or service person cannot close the door 616 by hand.

  By the way, although the service person can know the unlocking method of the locked state by a work book or training, the user cannot know. Therefore, in the locked state, the user cannot normally close the door 616 by himself / herself, and the toner in the hopper 625 is depleted, and a good image forming operation cannot be continued.

  Therefore, in this embodiment, the door 616 can be closed from the locked state where the door 616 cannot be closed by rotating the bossed gear 601 and separating the latch lever 602 and the connecting shaft 603 from each other. Recovery processing to shift to the state is executed.

  7, if the result of the determination in step S901 is that the door opening / closing sensor 620 is ON (“YES” in step S901), the CPU 201a advances the process to step S902, that is, the CPU 201a passes through the sensor IF 209. The output of the phase sensor 614 is read to determine whether or not the phase sensor 614 is ON (step S902) If the phase sensor 614 is ON, the claw is released by the gear 601 with a boss, the latch lever 602, and the connecting shaft 603. The lever 638 is fixed, and the door 616 cannot be closed (the locked state (FIG. 8B)).

  As a result of the determination in step S902, when the phase sensor 614 is ON (“YES” in step S902), the CPU 201a advances the process to step S903. That is, the CPU 201a controls the toner unit driving circuit 504 of the motor control unit 207 to send a signal for driving the DC motor 604, and drives the DC motor 604 counterclockwise (step S903). At this time, when the DC motor 604 rotates counterclockwise, the gear 601 with the boss rotates, and the gear 601 with the boss and the latch lever 602 are not in contact with each other. As a result, the latch lever 602 swings around the fulcrum 602b, and the convex portion 602a of the latch lever 602 is positioned at the detection position of the phase sensor 614. At this time, the latch lever 602 and the connecting shaft 603 are separated from each other. Next, the CPU 201a waits for a predetermined time with the DC motor 604 being driven (step S904).

  FIG. 10 is a timing chart for shifting the door 616 from the non-closeable state to the closeable state in the recovery process. In the description of FIG. 10, as in the description of FIG. 9, rotating the DC motor counterclockwise is referred to as turning on the DC motor, and stopping the DC motor is referred to as turning off the DC motor.

  Hereinafter, based on the ON / OFF of the DC motor 604, the ON (transmission) / OFF (shielding) of the phase sensor 614, and the non-closeable / closeable state of the door 616, the door 616 can be closed from the non-closeable state. The operation for shifting to will be described. In FIG. 10, the description of the operation of the gear 601 with the boss and the latch lever 602 and the state of the claw 640 of the door 616 is omitted.

  In FIG. 10, when the phase sensor 614 is in the transmissive state and the door 616 is not closed, the DC motor 604 is turned on (point a), and the DC motor 604 is rotated counterclockwise for a predetermined time 726. The predetermined time 726 is a predetermined time sufficient for the phase sensor 614 to enter the shielding state from the transmission state. Then, after the phase sensor 614 enters the shielding state, the rotational drive of the DC motor 604 is stopped (point b). As a result, the door opening / closing mechanism is unlocked, and the user can close the door 616.

  Returning to FIG. 7, the DC motor 604 is driven counterclockwise (step S903), and after waiting for a predetermined time (step S904), the CPU 201a returns the process to step S902, and again whether the phase sensor 614 is ON. Judge whether or not.

  As a result of the determination in step S902, when the phase sensor 614 is not ON (“NO” in step S902), the CPU 201a advances the process to step S905. That is, the CPU 201a sends a signal for stopping the DC motor 604 to the toner unit driving circuit 504 of the motor control unit 207, and stops the DC motor 604 (step S905). At this time, if the DC motor 604 is already in the stopped state, the CPU 201a does not perform any particular processing. If the output of the phase sensor 614 is in the OFF state, the user or service person can close the door 616 by hand.

  Thereafter, the CPU 201a returns the process to step S901 and confirms that the door 616 is closed. That is, the CPU 201a finishes this process after the door 616 in which the door opening / closing sensor 620 is OFF can be closed (“NO” in step S901).

  Even when the phase sensor 614 has not been turned on from the beginning of this process (“NO” in step S902), the CPU 201a advances the process to step S905 and performs the same processing as described above.

  If the door opening / closing sensor 620 is not ON as a result of the determination in step S901 immediately after the start of the process (“NO” in step S901), the CPU 201a ends this process. This is because if the door opening / closing sensor 620 is OFF, the door 616 is closed and it is not necessary to shift to the closeable state.

  According to the process of FIG. 7, it is confirmed whether or not the phase sensor 614 is in the ON (transmission) state. If the phase sensor 614 is in the transmission state (“YES” in step S902), the DC motor 604 is driven in the counterclockwise direction (step S902). S903) Then, the DC motor 604 is rotated for a predetermined time to turn off (shield) the phase sensor 614 (step SS904), whereby the claw 640 of the door 616 is opened and the locked state is released. The user can manually close the door 616. This also allows the user or service person to start toner replenishment by rotating a new toner container 618 after replacing the empty toner container 616, A good image forming process can be continued.

  According to the present embodiment, in the image forming apparatus configured to switch between the developer replenishing operation and the developer container door opening / closing operation by forward / reverse rotation of the drive source, a state in which the door 616 remains open and is not closed is detected. In this case, the drive source is rotated in the opening direction of the developer container. As a result, the state where the door 616 remains open and is not closed can be released, and the user or service person can manually close the door 616 to shift the developer to the developing device. Workability can be improved.

  In the present embodiment, the drive source is not limited to the DC motor 604 and is not particularly limited as long as it generates torque. In addition, the DC motor 604 is used as a common motor, and an operation of supplying toner to the developing device by switching the rotation direction and an operation of opening the door 616 by urging the claw release lever 638 by the latch lever 602 or the like. I switched. However, it can also be used as a drive source for executing different operations using two motors.

100 Image forming apparatus 600 Toner replenishing apparatus 601 Boss gear 602 Latch lever 603 Connection shaft 604 DC motor 616 Door 618 Toner container 620 Door open / close sensor 628 Mounting portion 638 Claw release lever 640 Claw

Claims (4)

Latent image forming means for forming an electrostatic latent image on the photoreceptor;
A developing unit having a storage unit for storing toner, and developing the electrostatic latent image using the toner in the storage unit to form an image;
A mounting portion on which a storage container storing toner to be supplied to the storage portion is mounted;
A door provided in the mounting portion and opened to take out the storage container from the mounting portion;
Driving means for driving the container mounted on the mounting portion to rotate by rotating in a first direction and opening the door by rotating in a second direction different from the first direction;
Control means for controlling the drive means;
First detecting means for detecting that the door is opened;
Prohibiting means for prohibiting the door from being closed when the driving means is driven to rotate in the second direction and the phase of the driving means reaches a predetermined phase;
Second detecting means for detecting the phase of the driving means,
When the control means detects that the door is opened by the first detection means, and the phase of the drive means is the predetermined phase based on the detection result of the second detection means, An image forming apparatus, wherein the driving unit is rotationally driven in the second direction so that the phase of the driving unit does not become the predetermined phase. The prohibiting means includes a first swinging member that swings when the driving unit is rotationally driven, and a second swinging member that swings to open and close the door,
When the phase of the driving means becomes the predetermined phase, the first swing member and the second swing member are maintained in contact with each other,
The image forming apparatus according to claim 1, wherein the first swing member and the second swing member are separated when the phase of the driving unit reaches the predetermined phase.   The image forming apparatus according to claim 2, wherein the second detection unit detects the position of the driving unit based on a position of the first swing member.   The image forming apparatus according to claim 1, wherein the control unit rotates the driving unit in the second direction for a predetermined time.