JP2013125142A - Developer supply device and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer supply device configured to accurately determine a toner empty state in an image forming device, to prevent image density reduction or carrier deposition on a photoreceptor, and to continue a print job until a cartridge is replaced with a new one, and to provide an image forming device using the same.SOLUTION: A developer supply device 101 includes a cartridge 22, a hopper 103, a screw member for conveying developer, and a control device 32 for controlling operation of the screw member. In the hopper 103, the screw member and a residual amount sensor 106 for detecting the amount of developer in the hopper 103 are provided. The developer supply device includes: a function of controlling operation of the screw member in accordance with an output of the residual amount sensor 106; a function of calculating the amount of developer in the hopper 103 as a count value; and a function of determining whether the amount of developer in the hopper 103 is enough to continue print operation when there is no developer in the cartridge 22.

Description

  The present invention relates to a developer replenishing device and an image forming apparatus using the same, and more particularly to an image forming apparatus such as an electrostatic copying machine, a laser printer, and a facsimile machine that forms an image using toner by an electrophotographic method. The present invention relates to an image forming apparatus using a developing device using a two-component developer containing toner and a magnetic carrier.

  2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as copying machines, printers, and facsimiles are known. An electrophotographic image forming apparatus forms an electrostatic latent image on the surface of a photoreceptor, for example, a photoreceptor drum, and develops the electrostatic latent image by supplying toner to the photoreceptor drum by a developing device. The toner image formed on the photosensitive drum by development is transferred to a sheet such as paper and fixed by a fixing device.

2. Description of the Related Art In recent years, two-component developers (hereinafter simply referred to as “developers”) that are excellent in toner charge stability are often used in image forming apparatuses that support full color and high image quality.
The developer is composed of toner and carrier, and the toner and the carrier are rubbed by stirring them in the developing device (hereinafter simply referred to as “developing tank”), and the toner is appropriately charged by this friction. Is obtained.

Since the toner in the two-component developer in the developing tank is consumed every time the image forming operation is repeated, stable image quality cannot be maintained unless new toner is supplied to the developing tank.
Usually, a developer cartridge for storing developer for replenishment is mounted on the apparatus. There are two types: a type that replenishes the developer directly from the cartridge and a type that has a hopper that temporarily stores a certain amount of developer.

  In the former type, when there is no developer to be supplied in the cartridge during the image forming operation, the printing operation is temporarily stopped until a new cartridge is replaced.

  The latter type uses the developer in the hopper that has been temporarily stored even if the developer in the cartridge runs out, and continues the printing operation. During this time, it can be replaced with a new cartridge. This machine is designed to prevent the job efficiency from being reduced by adopting this type (see Patent Document 1).

JP 2009-271181 A

  In the developing device using the two-component developer described above, a message prompting to replace the cartridge is displayed when there is no supply from the cartridge filled with the developer to the hopper for temporarily storing the developer in the machine. Then, the continuous mode in which the printing operation is continued using only the developer stored in the hopper is set.

  Further, when the remaining amount of developer stored in the hopper during the continuous mode decreases, the amount of developer replenished to the developing tank decreases, the toner concentration in the developer gradually decreases, and the image density decreases and the photoconductor Since the frequency of occurrence of carrier development (carrier adhesion) on the drum increases, it is necessary to accurately detect toner empty to prevent image density reduction and carrier development.

  The toner empty detection is, for example, toner empty when the toner concentration of the developer detected by a toner supply detection sensor (for example, a magnetic permeability sensor) does not increase after instructing toner supply to the hopper. Is determined (detected).

  However, this method has a problem in that the toner empty cannot be determined at an optimal timing because the determination (detection) varies depending on the environmental change and the developer usage history.

  The present invention has been made in view of the above-described conventional problems, and can accurately determine the toner empty timing by accurately grasping the toner amount in the hopper in the image forming apparatus. The present invention provides a developer replenishing device and an image forming apparatus using the same, which can prevent a decrease in image density due to a decrease in toner density and occurrence of carrier adhesion to a photoconductor and continue a print job until a new cartridge is replaced. For the purpose.

  A developer supply device and an image forming apparatus using the same according to the present invention for solving the above-described problems are as follows.

  The present invention relates to a replaceable developer container that contains a developer, a hopper that temporarily stores the developer supplied from the developer container, and a development that replenishes the developing device with the developer stored in the hopper. In the developer replenishing device comprising a developer replenishing means and a control means for controlling the operation of the developer replenishing means, the developer supplied from the developer container as the developer replenishing means is provided in the hopper. And a remaining amount sensor for detecting the amount of the developer supplied into the hopper, and the control means includes the remaining amount The function of controlling the operation of the screw member in accordance with the output of the sensor (developer transport control means), and the rotation time of the screw member are monitored and stored in the hopper. A function for calculating the amount of the agent as a count value (count value calculation means), and when there is no developer in the developer container, or when developer transport from the developer container to the hopper is prohibited, And a function (printing operation determination means) for determining whether or not the amount of developer in the hopper can continue the printing operation based on the count value.

  In the present invention, it is preferable that the remaining amount sensor is provided at a position where the developer supplied from the developer container into the hopper can be detected.

  Further, the present invention uses a positive coefficient as the count value calculation method when it is determined that the developer is present in the developer container with respect to the rotation time of the screw member in the hopper. It is preferable to calculate using a negative coefficient when it is determined that there is no developer in the developer container and when the developer conveyance from the developer container to the hopper is prohibited.

  In the present invention, the positive coefficient in the count value calculation method is switched between high and low output from the remaining amount sensor while the screw member is rotating, and (high positive coefficient)> (low It is preferable to calculate as a positive coefficient).

  In the present invention, the developer in the developer container preferably contains either a two-component developer composed of toner and a carrier or a one-component developer composed of toner alone.

  The present invention also provides an exposure apparatus (for example, a laser scanner) that forms an electrostatic latent image on the surface of a photoreceptor (for example, a photoreceptor drum) provided in an image forming apparatus in which the control apparatus is used. A function (dot counting means) that counts dot data according to image data to be transmitted to the unit, and the developer replenishing means to the developing device according to the counted dot data (by the dot counting means). And an instruction function for supplying the developer.

  For example, when the dot data counted is small, the control device instructs the developer replenishing device to replenish a small amount of developer to the developer replenisher, and when the dot data is large, The developer replenishing device may be instructed to replenish a large amount of developer to the developing device. The amount of developer to be replenished is preferably set in advance according to dot data.

  The present invention also provides a photoconductor on which an electrostatic latent image is formed, a charging device that charges the surface of the photoconductor, an exposure device that forms an electrostatic latent image on the surface of the photoconductor, and a static on the surface of the photoconductor. An image forming apparatus for forming an image by an electrophotographic method, comprising: a developing device that supplies a developer to an electrostatic latent image to form an image; and a developer replenishing device that replenishes the developer to the developer. The developer supply device according to any one of claims 1 to 6 is used as a configuration of the developer supply device.

  According to the developer supply device of the present invention, a replaceable developer container that stores the developer, a hopper that temporarily stores the developer supplied from the developer container, and the developer that is stored in the hopper In the developer replenishing device comprising a developer replenishing means for replenishing the developing device and a control means for controlling the operation of the developer replenishing means, the developer is provided in the hopper as the developer replenishing means. A screw member for temporarily storing the developer supplied from the container and transporting the developer by a rotation operation; and a remaining amount sensor for detecting the amount of the developer supplied into the hopper, the control The apparatus includes a function (developer conveyance control means) for controlling the operation of the screw member according to the output of the remaining amount sensor, and a rotation time of the screw member to monitor the hopper. A function (count value calculation means) for calculating the developer amount stored in the developer container as a count value, and when there is no developer in the developer container or when the developer is conveyed from the developer container to the hopper. A developer (printing operation determining means) for determining whether or not the amount of developer in the hopper can be continued based on the count value when prohibited, the developer in the hopper By calculating the amount using the remaining amount counter, it is possible to accurately grasp the developer amount, and therefore it is possible to accurately determine the toner empty timing. In addition, when the remaining amount counter reaches a preset threshold value, it is possible to prevent a decrease in the amount of developer replenishment from the hopper to the developing tank by determining that the printing operation can be continued or not. In addition, it is possible to prevent the occurrence of image density reduction and carrier adhesion to the photoreceptor due to toner density reduction of the developer.

  Further, according to the present invention, since the remaining amount of developer in the hopper can be accurately grasped, it is prevented from being determined that the toner is empty even though the printing operation is still possible. It is possible to reduce the downtime of the machine by making the print operation ready state (continuous run mode) as long as possible, so it is possible to continue without stopping the print job until it is replaced with a new cartridge. It can be carried out.

  Further, according to the present invention, the remaining amount sensor is provided at a position where the developer supplied from the developer container into the hopper can be detected, thereby reliably detecting the presence of the developer. be able to.

  Further, according to the present invention, as the calculation method of the count value, when it is determined that the developer is present in the developer container with respect to the rotation time of the screw member in the hopper, a positive coefficient is used. When it is determined that there is no developer in the developer container and when the developer conveyance from the developer container to the hopper is prohibited, it is calculated using a negative coefficient. The amount of developer in the hopper can be accurately grasped.

  According to the present invention, the positive coefficient in the count value calculation method is switched between high and low output from the remaining amount sensor while the screw member is rotating, and (high positive coefficient)> ( By calculating as a low positive coefficient, it is possible to grasp the amount of developer stored in the hopper more accurately.

  In addition, according to the present invention, as the developer in the developer container, either a two-component developer composed of toner and carrier or a one-component developer composed only of toner is stored, so that the type of developer The developer can be detected without depending on the above.

  According to the invention, as the configuration of the control device, the image is transmitted to an exposure device that forms an electrostatic latent image on the surface of a photoconductor (for example, photoconductor drum) provided in an image forming apparatus in which the control device is used. A function for counting dot data according to image data (dot counting means), and a replenishment of developer to the developing device with respect to the developer replenishing means according to the counted dot data (by the dot counting means) And a function of instructing the amount of toner, the amount of toner consumed for image formation can be predicted and the developer can be replenished, so that a decrease in the developer replenishment amount can be prevented in advance.

  In addition, according to the image forming apparatus of the present invention, a photosensitive member on which an electrostatic latent image is formed, a charging device that charges the surface of the photosensitive member, and an exposure device that forms an electrostatic latent image on the surface of the photosensitive member. A developing device that supplies a developer to the electrostatic latent image on the surface of the photoreceptor to form an image; and a developer replenishing device that replenishes the developer to the developer, and forms an image by electrophotography. In the image forming apparatus, the developer replenishing device according to any one of claims 1 to 6 is used as a configuration of the developer replenishing device, whereby development in a hopper constituting the developer replenishing device is performed. Since the amount of the agent can be grasped with high accuracy, the toner empty timing can be determined with high accuracy. As a result, it is possible to prevent a decrease in the amount of developer replenished from the hopper to the developer tank, thereby preventing a decrease in image density due to a decrease in the toner concentration of the developer and the occurrence of carrier adhesion to the photoreceptor. Can do.

1 is an explanatory diagram showing an overall configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a schematic configuration diagram of a developer supply device according to an embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of a developing device and a developer supply device section according to the present embodiment. FIG. 3A is a plan view showing a configuration of a hopper constituting the developer supply device, and a side view showing a configuration of the hopper. FIG. 3 is a block diagram showing an electrical configuration for performing developer supply control in the developer supply device. 4 is a flowchart illustrating conveyance of a developer from a cartridge to a hopper in the developer supply device. FIG. 2 is an explanatory diagram showing a state where a developer is present in a hopper during continuous run control in the developer replenishing device, and a graph showing it in time series. It is explanatory drawing which shows a state when continuous run control is cancelled | released in the middle of the continuous run control in FIG. 7, and a graph which shows it in time series. It is a table | surface which shows the specific example of the count correction coefficient output by the residual amount sensor which concerns on this embodiment. It is a table | surface which shows the specific example of the setting value of the counter preset to the residual amount counter which concerns on this embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory diagram showing an overall configuration of an image forming apparatus according to an embodiment of the present invention, which is an example of an embodiment of the present invention.

  In the present embodiment, as shown in FIG. 1, a photosensitive drum 3 on which an electrostatic latent image is formed, a charger (charging device) 5 for charging the surface of the photosensitive drum 3, and the surface of the photosensitive drum 3 An exposure unit (exposure device) 1 that forms an electrostatic latent image on the surface, a developing device 2 that forms a toner image by supplying toner to the electrostatic latent image on the surface of the photosensitive drum 3, and a toner supply to the developing device 2 A developer replenishing device 101, an intermediate transfer belt unit (transfer device) 8 for transferring the toner image on the surface of the photosensitive drum 3 to a recording medium, and a fixing unit (fixing device) 12 for fixing the toner image on the recording medium. The image forming apparatus 100 that forms an image using toner by electrophotography employs the characteristic image forming apparatus configuration according to the present invention.

  The image forming apparatus 100 forms a multicolor or single color image on a predetermined sheet (recording paper, recording medium) according to image data transmitted from the outside. A scanner or the like may be provided above the image forming apparatus 100.

First, the overall configuration of the image forming apparatus 100 will be described.
As shown in FIG. 1, the image forming apparatus 100 handles image data for each color component of black (K), cyan (C), magenta (M), and yellow (Y). An image and a yellow image are formed, and a color image is formed by superimposing the images of the respective color components.

  Therefore, in the image forming apparatus 100, as shown in FIG. 1, the developing device 2 (2a, 2b, 2c, 2d) and the photosensitive drum 3 (3a, 3b, 3c) are formed so that images of the respective color components are formed. , 3d), four chargers 5 (5a, 5b, 5c, 5d) and four cleaner units 4 (4a, 4b, 4c, 4d). In other words, four image forming stations (image forming units) each including the developing device 2, the photosensitive drum 3, the charger 5, and the cleaner unit 4 are provided.

  The symbols a to d indicate that a is a member for forming a black image, b is a member for forming a cyan image, c is a member for forming a magenta image, and d is a member for forming a yellow image. It is a thing. Further, the image forming apparatus 100 includes an exposure unit 1, a fixing unit 12, a sheet conveyance path S, a paper feed tray 10, and a paper discharge tray 15.

The charger 5 uniformly charges the surface of the photosensitive drum 3 to a predetermined potential.
As the charger 5, a contact brush type charger or a non-contact charger type charger may be used in addition to the contact roller type charger shown in FIG.

  As shown in FIG. 1, the exposure unit 1 is a laser scanning unit (LSU) including a laser irradiation unit and a reflection mirror. However, in addition to the laser scanning unit, the exposure unit 1 may be an EL (electroluminescence) in which light emitting elements are arranged in an array or an LED writing head. The exposure unit 1 exposes the charged photosensitive drum 3 according to the input image data, thereby forming an electrostatic latent image corresponding to the image data on the surface of the photosensitive drum 3.

  The developing device 2 visualizes (develops) the electrostatic latent image formed on the photosensitive drum 3 with one of K, C, M, and Y toners. Above the developing device 2 (2a, 2b, 2c, 2d), a replenishment pipe 102 (102a, 102b, 102c, 102d) and a hopper 103 (103a, 103b, 103c, 103d) constituting the developer replenishing device 101 are provided. A developer container (hereinafter referred to as a “cartridge”) 22 (22a, 22b, 22c, 22d) is provided.

  The developer supply device 101 is disposed above the developing tank 111 and has a replaceable cartridge 22 storing unused developer (powder toner), and temporarily stores the developer inside the machine. The developer is supplied from the hopper 103 to the developing tank 111 via a supply pipe (developer supply mechanism) 102.

  The cleaner unit 4 removes and collects the toner remaining on the surface of the photosensitive drum 3 after the development and image transfer processes.

  An intermediate transfer belt unit 8 is disposed above the photosensitive drum 3. The intermediate transfer belt unit 8 includes an intermediate transfer roller 6 (6a, 6b, 6c, 6d), an intermediate transfer belt 7, an intermediate transfer belt driving roller 71, an intermediate transfer belt driven roller 72, an intermediate transfer belt tension mechanism 73, and an intermediate transfer. A belt cleaning unit 9 is provided.

  The intermediate transfer belt 6, the intermediate transfer belt drive roller 71, the intermediate transfer belt driven roller 72, and the intermediate transfer belt tension mechanism 73 stretch the intermediate transfer belt 7 and rotationally drive the intermediate transfer belt 7 in the direction of arrow B in FIG. It is something to be made.

  The intermediate transfer roller 6 is rotatably supported by an intermediate transfer roller mounting portion in the intermediate transfer belt tension mechanism 73 of the intermediate transfer belt unit 8. A transfer bias for transferring the toner image on the photosensitive drum 3 onto the intermediate transfer belt 7 is applied to the intermediate transfer roller 6.

  The intermediate transfer belt 7 is provided so as to be in contact with each photosensitive drum 3. A color toner image (multicolor toner image) is formed on the intermediate transfer belt 7 by sequentially superimposing and transferring the toner images of the respective color components formed on the photosensitive drum 3. The intermediate transfer belt 7 is formed in an endless shape using a film having a thickness of, for example, about 100 μm to 150 μm.

  Transfer of the toner image from the photosensitive drum 3 to the intermediate transfer belt 7 is performed by the intermediate transfer roller 6 in contact with the back side of the intermediate transfer belt 7. A high voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the intermediate transfer roller 6 in order to transfer the toner image.

  The intermediate transfer roller 6 is formed based on a metal (for example, stainless steel) shaft having a diameter of, for example, 8 to 10 mm, and the surface is covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). With this conductive elastic material, the intermediate transfer roller 6 can uniformly apply a high voltage to the intermediate transfer belt 7. In this embodiment, a roller-shaped transfer electrode (intermediate transfer roller 6) is used as the transfer electrode, but a brush or the like can also be used.

  As described above, the electrostatic latent images on the respective photosensitive drums 3 are visualized with toners corresponding to the respective color components to become toner images, and these toner images are superimposed and laminated on the intermediate transfer belt 7. As described above, the stacked toner images are moved to a contact position (transfer portion) between the conveyed paper and the intermediate transfer belt 7 by the rotation of the intermediate transfer belt 7, and the transfer roller disposed at this position is moved. 11 is transferred onto the paper. In this case, the intermediate transfer belt 7 and the transfer roller 11 are pressed against each other at a predetermined nip, and a voltage for transferring the toner image onto the sheet is applied to the transfer roller 11. This voltage is a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner.

  In order to obtain the nip constantly, either the transfer roller 11 or the intermediate transfer belt drive roller 71 is made of a hard material such as metal, and the other is a soft material such as an elastic roller (elastic rubber roller or foamable resin roller). Etc.).

  The toner adhering to the intermediate transfer belt 7 due to the contact between the intermediate transfer belt 7 and the photosensitive drum 3 and the toner image remaining on the intermediate transfer belt 7 without being transferred when the toner image is transferred from the intermediate transfer belt 7 to the sheet. The toner is removed and collected by the intermediate transfer belt cleaning unit 9 because it causes toner color mixing in the next step.

  The intermediate transfer belt cleaning unit 9 is provided with a cleaning blade (cleaning member) that contacts the intermediate transfer belt 7. The portion of the intermediate transfer belt 7 that is in contact with the cleaning blade is supported by the intermediate transfer belt driven roller 72 from the back side.

  The paper feed tray 10 is for storing sheets (for example, recording paper) used for image formation, and is provided below the image forming unit and the exposure unit 1. On the other hand, a paper discharge tray 15 provided in the upper part of the image forming apparatus 100 is for placing printed sheets face down.

  Further, the image forming apparatus 100 is provided with a sheet conveyance path S for guiding the sheet of the paper feed tray 10 and the sheet of the manual feed tray 20 to the paper discharge tray 15 via the transfer unit and the fixing unit 12. . The transfer unit is located between the intermediate transfer belt driving roller 71 and the transfer roller 11.

  Further, a pickup roller 16 (16a, 16b), a registration roller 14, a transfer unit, a fixing unit 12, a conveyance roller 25 (25a to 25h), and the like are arranged in the sheet conveyance path S.

  The conveyance rollers 25 are small rollers for promoting and assisting conveyance of the sheet, and a plurality of conveyance rollers 25 are provided along the sheet conveyance path S. The pickup roller 16 a is a pull-in roller that is provided at the end of the paper feed tray 10 and supplies sheets one by one from the paper feed tray 10 to the sheet conveyance path S. The pickup roller 16 b is a drawing roller that is provided near the manual feed tray 20 and supplies sheets from the manual feed tray 20 to the sheet conveyance path S one by one. The registration roller 14 temporarily holds the sheet conveyed in the sheet conveyance path S, and conveys the sheet to the transfer unit at a timing when the leading edge of the toner image on the intermediate transfer belt 7 and the leading edge of the sheet are aligned.

  The fixing unit 12 includes a heat roller 81, a pressure roller 82, and the like. The heat roller 81 and the pressure roller 82 rotate with the sheet interposed therebetween. The heat roller 81 is controlled by a control unit (not shown) so as to have a predetermined fixing temperature. This control unit controls the temperature of the heat roller 81 based on a detection signal from a temperature detector (not shown).

  The heat roller 81 heat-presses the sheet together with the pressure roller 82 to melt, mix, and press the color toner images transferred to the sheet, and heat-fix the sheet. The sheet on which the multicolor toner image (each color toner image) is fixed is conveyed to the reverse sheet discharge path of the sheet conveyance path S by the plurality of conveyance rollers 25 and is reversed (the multicolor toner image is on the lower side). Are discharged onto the paper discharge tray 15.

Next, the sheet conveying operation by the sheet conveying path S will be described.
As shown in FIG. 1, the image forming apparatus 100 is provided with a paper feed tray 10 that stores sheets in advance and a manual feed tray 20 that is used when printing a small number of sheets as described above. Pickup rollers 16 (16a, 16b) are disposed on both trays, and the pickup rollers 16 supply sheets one by one to the sheet conveyance path S.

  In the case of single-sided printing, the sheet conveyed from the sheet feeding tray 10 is conveyed to the registration roller 14 by the conveyance roller 25a in the sheet conveyance path S, and is stacked on the leading edge of the sheet and the intermediate transfer belt 7 by the registration roller 14. Then, the toner image is conveyed to a transfer portion (contact position between the transfer roller 11 and the intermediate transfer belt 7) at a timing when the leading edge of the toner image is aligned. In the transfer portion, a toner image is transferred onto the sheet, and this toner image is fixed on the sheet by the fixing unit 12. Thereafter, the sheet is discharged onto the discharge tray 15 from the discharge roller 25c via the conveyance roller 25b.

  Further, the sheet conveyed from the manual feed tray 20 is conveyed to the registration roller 14 by a plurality of conveying rollers 25 (25f, 25e, 25d). Subsequent sheet conveyance operations are discharged to the sheet discharge tray 15 through a process similar to that for the sheets supplied from the sheet feed tray 10 described above.

  On the other hand, in the case of double-sided printing, the trailing edge of the sheet that has completed single-sided printing and passed through the fixing unit 12 as described above is chucked by the paper discharge roller 25c. Next, the sheet is guided to the conveying rollers 25g and 25h by the reverse rotation of the paper discharge roller 25c, and after the printing on the back surface is again performed through the registration roller 14, it is discharged to the paper discharge tray 15.

Next, the characteristic configuration of the developer supply device 101 according to the present embodiment will be described in detail.
FIG. 2 is a schematic configuration diagram of the developer supply device according to the present embodiment, FIG. 3 is a cross-sectional view illustrating the configurations of the development device and the developer supply device unit according to the present embodiment, and FIG. It is a top view which shows the structure of the hopper which comprises an apparatus, and a side view which shows the structure of the said hopper.

  As shown in FIGS. 2 and 3, the developer replenishing device 101 is disposed on the upper side of the developing tank 111 of the developing device 2, and the replaceable cartridge (developer container) 22, the developer conveyed from the cartridge 22 A hopper 103 for temporary storage and a replenishment pipe 102 for supplying developer discharged from the hopper 103 into the developing tank 111 are configured.

In the main body of the image forming apparatus, a rail (not shown) for mounting the replaceable cartridge 22 at a proper position, and a cartridge drive which is a developer transport means for transporting the developer in the cartridge 22 to the hopper 103. A motor 104 is provided.
The hopper 103 has a storage portion 113b for temporarily storing the developer in the apparatus, and a first transport member 131 and a second transport member 132 configured by screw members for supplying the developer to the developing tank 111. A hopper drive motor 105 for rotating the first transport member 131 and the second transport member 132 is provided.

  As shown in FIG. 3, the cartridge 22 has a configuration in which the developer is transported to the hopper 103 by rotating the container itself, a screw that is not shown, and a screw or the like that is configured inside the cartridge 22 The developer is transported to the hopper 103 by rotating the developer transport member.

  The hopper 103 is provided with a toner replenishing port 113a through which the developer in the cartridge 22 is replenished into the hopper 103, and a remaining amount sensor 106 is provided on a vertical surface in the immediate vicinity of the toner replenishing port 113a.

  The remaining amount sensor 106 is a piezoelectric sensor, and the sensor head portion of the detection portion vibrates the diaphragm by a resonance circuit, and an output signal at this time is a Low signal. When the developer is sufficiently present on the head surface, the vibration of the diaphragm stops and a high signal is output.

Such types of piezoelectric sensors are commercially available, and examples thereof include powder level sensors LTS series, TSP series (both are trade names, manufactured by TDK Corporation), and the like.
The surface of the piezoelectric sensor head is wiped in synchronism with screw rotation by urethane mylar on the screw circumference.

  Further, as shown in FIGS. 3, 4A and 4B, the hopper 103 has a storage portion 113b for temporarily storing the developer, and 2 for conveying the developer in the storage portion 113b. It comprises a first conveying member 131 and a second conveying member 132 which are opposing screw members, a hopper drive motor 105 and a gear 115 for rotating the first conveying member 131 and the second conveying member 132.

  The first transport member 131 and the second transport member 132 are juxtaposed so that their peripheral surfaces face each other via a partition plate and their axes are parallel to each other, and rotate in opposite directions. Is set. As shown in FIGS. 4A and 4B, the first transport member 131 transports the developer in the right direction of the arrow, and the second transport member 132 transports the developer in the left direction of the arrow. Is set to

  The hopper 103 includes a toner dropping port 113c through which the developer conveyed by the rotation of the screws of the first conveying member 131 and the second conveying member 132 is finally supplied to the developing tank 111.

Next, characteristic developer replenishment control in the developer replenishment device 101 of the image forming apparatus 100 of the present embodiment will be described.
FIG. 5 is a block diagram showing an electrical configuration for performing development replenishment control in the developer replenishing apparatus of this embodiment.

  As shown in FIG. 5, the image forming apparatus 100 includes a dot count device 33 that detects an integrated value of the number of pixels of an image formed on the photosensitive drum 3, and a developer near the toner supply port in the developing tank 111. And a printer engine unit 341 including an image forming process unit 36 and a paper transport unit 37, a cartridge driving motor 104 for rotating the cartridge 22 in the developer supply device 101, and a developing tank. A hopper drive motor 105 that drives screw members (first conveyance member 131, second conveyance member 132) for supplying toner to 111, a remaining amount sensor 106 that detects the amount of developer in the hopper 103, a remaining amount counter 35, A control device 32 for controlling these is provided.

  In the present embodiment, the developer replenishment control in the developer replenishing device 101 is configured so that the control device 32 functions as a control unit that controls the developer replenishment, and the dot count device 33, the remaining amount counter 35, and the cartridge drive. It is executed using the motor 104, the hopper drive motor 105, the remaining amount sensor 106, and the magnetic permeability sensor 119.

  For the developer replenishment control, general means can be used, and examples thereof include control using a toner density detection sensor, control according to patch image density, control according to dot count, and the like. Among these, control according to dot count is preferable.

  The dot count device 33 detects an integrated value of the number of pixels of an image (electrostatic latent image) formed on the photosensitive drum corresponding to the print image. By this dot count device 33, the integrated value count value of the number of pixels of the image to be printed and the image printed so far is input to the control device 32 as a dot count value and stored in a storage unit (not shown).

  Further, from the integrated value of the number of pixels of the image detected by the dot count device 33, the amount of toner consumed for image formation can be predicted.

  Based on the dot count value, the control device 32 obtains the toner amount consumed in the image formation, and instructs the hopper drive motor 105 to drive the screw member in the hopper 103 according to the toner amount. The developer tank 111 is instructed to supply the developer.

  As the configuration of the control device 32, developer conveyance control means that functions as a means for controlling the operation of the screw member according to the output of the remaining amount sensor 106, and the rotation time of the screw member is monitored and stored in the hopper 103. Count value calculating means that functions as a count value for calculating the amount of developer that is present, and when there is no developer in the cartridge 22 or when the developer conveyance from the cartridge 22 to the hopper 103 is prohibited, Printing operation determination means functioning as a determination whether or not the developer amount in the hopper 103 can continue the printing operation based on the count value. In the present embodiment, a remaining amount counter 35 is employed as one that functions as a count value calculation unit.

  In this manner, image formation is executed by the printer engine unit 341 including the image forming process unit 36 and the paper transport unit 37, and developer (toner) corresponding to the amount of toner consumed thereby is developed from the hopper 103. The developing tank 111 of the apparatus 2 is replenished.

Next, the case where the developer is replenished to the developing device 2 in the developer replenishing device 101 of the present embodiment will be described based on a flowchart.
FIG. 6 is a flowchart showing the conveyance of the developer from the cartridge to the hopper in the developer supply device of this embodiment.

  The remaining amount sensor 106 provided in the vicinity of the toner replenishing port 113a through which the developer conveyed from the cartridge 22 is replenished to the hopper 103 has a high signal (when the water level of the developer in the sensor head portion exceeds a certain level. This is a piezoelectric sensor that outputs 4.5 to 5.0 V) and outputs a Low signal (0 to 0.5 V) at a certain sampling rate when the height falls below a certain height.

  When the developer supply by the developer supply device 101 is started, the developer present in the hopper 103 is detected by the remaining amount sensor 106 as shown in FIG. It is determined whether the signal is a low signal (step S1).

  If it is determined in step S1 that the output signal from the remaining amount sensor 106 is a low signal or the average of the most recent output signal is low, it is determined that there is no developer near the remaining amount sensor 106. Then, the cartridge driving motor 104 for driving the developer conveying means for conveying the developer from the cartridge 22 to the hopper 103 is rotationally driven (step S2).

  On the other hand, if it is determined in step S1 that the output signal from the remaining amount sensor 106 is a low signal or the average of the latest output signals is not low, it is determined that the developer is present in the hopper 103. Then, the cartridge drive motor 104 is stopped (step S3). Then, the process returns to step S1.

  It is determined whether or not the cartridge drive motor 104 has been driven to rotate and the continuous rotation time (operation time) of the cartridge drive motor 104 has become longer (e.g., X seconds) than a preset value (for example, X seconds). Step S4).

  If it is determined in step S4 that the continuous rotation time of the cartridge drive motor 104 is not greater than a preset value, the process returns to step S1.

  On the other hand, if it is determined in step S4 that the continuous rotation time of the cartridge drive motor 104 has become larger than a preset value, the output signal from the remaining amount sensor 106 is a high signal or Since the average of the most recent output signals does not become High, it is determined that the cartridge 22 has run out of developer (toner empty).

  When it is determined that the developer in the cartridge 22 has run out, a message is displayed to replace the corresponding color cartridge as the cartridge end (step S5).

  At this time, in the image forming apparatus that does not have the hopper 103, the printing operation cannot be continued. However, in the present embodiment, since the hopper 103 is provided, the developer in the hopper 103 is used. Thus, the mode can be changed to a mode for continuing the printing operation (continuous run mode).

Here, an overall outline of continuous run control in the developer supply device 101 of the present embodiment will be described in detail with reference to the drawings.
FIG. 7 is an explanatory diagram showing a state in which the developer is present in the hopper during continuous run control in the developer replenishing device of this embodiment, and a graph showing it in time series. FIG. 8 is a continuous run in FIG. It is explanatory drawing which shows a state when a continuous run control is cancelled | released in the middle of control, and a graph which shows it in time series.

  In this embodiment, as shown in FIGS. 7 and 8, the hopper 103 replenishes the toner replenishing port 113 a, which is a portion to which the developer is supplied from the cartridge 22, and replenishes the developer tank 111 from the hopper 103. The toner drop opening 113c, which is a part, is indicated by an “out” mark, and two opposed screw members (a first conveying member 131 and a second conveying member 132 (not shown) that are rotated by a hopper drive motor and a gear (not shown)). )) Is configured to temporarily store the developer in the hopper 103 and to supply the developer to the developing tank 111.

  As shown in FIG. 7, the inside of the hopper 103 at the time of machine installation (factory shipment) (T1) is in a cleaned empty state (state 1). Then, a new cartridge 22 is mounted on the developing device 2, and the hopper filling mode (normal mode) is performed by the first warm-up operation of the developing device 2 in the new cartridge 22.

Initially, since the remaining amount sensor 106 determines Low, the cartridge drive motor 104 is driven. Thereafter, the developer is supplied and the remaining amount sensor 106 determines High (state 2).
Then, the cartridge drive motor 104 is stopped by the High determination, and then the hopper drive motor 105 is driven to rotate the screw member.

  A partition plate 113d cut out in a rectangular wave shape is provided between the two opposing screw members, and the developer supplied from the cartridge 22 preferentially passes through the cutout portion of the partition plate 113d. It is configured to be conveyed to the toner drop opening 113c (signed).

  As the screw member rotates, the developer in the vicinity (marked) of the remaining amount sensor 106 is conveyed, and the remaining amount sensor 106 determines Low. The hopper drive motor 105 is stopped by the Low determination. Further, the cartridge driving motor 104 is driven to supply the developer to the hopper 103 until it is judged as High.

  By repeating the above operation several times, the developer is transported to the replenishing port (signing) to the developing tank 111 (state 3), and the hopper filling mode is completed and the printing operation is possible. (T2: completion of initial filling of hopper, completion of warm-up).

Next, the control after (State 3) shown in FIG. 7 will be described.
The actual toner replenishment instruction instructs the hopper drive motor 105 to replenish a small amount of developer to the developing tank 111 when the dot data counted by the dot count device 33 is small, and the dot data is large. In this case, the hopper driving motor 105 is instructed to supply a large amount of toner to the developing tank 111 as described above.

  As a result, in actuality, the opposing screw member is rotated by the rotation operation of the hopper drive motor 105, and the developer is gradually stored in the hopper 103 while supplying the developer to the developer tank 111 (state 4).

  In the present embodiment, a remaining amount counter 35 is provided to calculate the amount of developer temporarily stored in the hopper 103. In the counting method of the remaining amount counter 35, when it is determined that the developer is present in the cartridge 22 with respect to the screw rotation time in the hopper 103, it is determined that there is no developer in the cartridge 22. The negative coefficient is used for calculation at the time and when the developer conveyance from the cartridge 22 to the hopper 103 is prohibited.

  The positive count correction coefficient of the counting method for calculating the developer amount in the hopper 103 is more accurately stored in the hopper 103 when the output of the remaining amount sensor 106 during screw rotation is switched between High and Low. The amount can be indicated.

  When the remaining amount sensor 106 outputs Low during screw rotation, the amount of developer in the vicinity of the remaining amount sensor 106 is small, so the amount of developer stored in the hopper 103 is small. On the other hand, when the remaining amount sensor 106 outputs High during screw rotation, the amount of developer near the remaining amount sensor 106 is large, so the amount of developer stored in the hopper 103 increases. Therefore, the count correction coefficient is calculated as a positive correction coefficient for High> a positive correction coefficient for Low.

  As a specific count correction coefficient, as shown in FIG. 9, for example, when there is developer in the cartridge 22, the count correction coefficient when the remaining amount sensor 106 is high output is “+2”, and low output In this case, the count correction coefficient is set to “+1”. If there is no developer, the count correction coefficient is set to “−4”.

  The value of the remaining amount counter 35 obtained by multiplying the rotation time of the hopper drive motor 105 by a positive count correction coefficient is added as a remaining amount counter each time the dot replenishment instruction is given by the dot count device 33, and is temporarily stored in the hopper 103. It is stored in the machine body as a value that accurately indicates the amount of developer stored.

  The value of the remaining amount counter 35 increases every time the toner replenishment operation is repeated, and eventually reaches a predetermined developer upper limit threshold (T3: hopper filling mode is completed), and is the maximum temporarily stored in the hopper 103. The amount of developer is reached (state 5).

  As a specific counter value, as shown in FIG. 10, for example, the counter setting value indicating the developer amount in the hopper 103 is set to “0” when the machine is installed (initial value), and the developer lower limit. The threshold setting value is “100”, and the developer upper limit threshold setting value is “1000”.

  Thereafter, when there is sufficient developer in the cartridge 22, the remaining amount counter 35 continues to count at the developer upper limit threshold (state 6).

  Normally, the developer used for image formation is replenished to the developing tank 111 by performing the printing operation, so that the amount of developer in the cartridge 22 gradually decreases and eventually becomes empty.

  Various methods for determining the empty state in the cartridge 22 can be considered. In this embodiment, the cartridge drive motor 104 is driven when the output of the remaining amount sensor 106 is determined to be Low, and the output of the remaining amount sensor 106 is determined as High. The continuous rotation time of the cartridge drive motor 104 until this is measured. Then, when the measurement time exceeds a certain value, it is determined that the developer in the cartridge 22 has become empty. Then, a message for requesting cartridge replacement is displayed.

  At this timing, the rotation operation of the cartridge drive motor 104 is prohibited, and the developer supply to the developing tank 111 is a mode in which only the developer temporarily stored in the hopper 103 is used and the printing operation is continued ( Transition to continuous run mode) (T4: start of continuous run mode) (state 7).

  The calculation method of the remaining amount counter in the mode (continuous run mode) in which the printing operation is continued using only the developer temporarily stored in the hopper 103 is linked to the rotation operation of the hopper driving motor 105. Since the amount of developer in 103 is reduced, the calculation is performed using a negative count correction coefficient.

  As shown in (state 8) and (state 9) in FIG. 7, the remaining amount counter 35 is inclined with a negative count correction coefficient multiplied by the rotation time of the hopper drive motor 105 together with the developer replenishment operation accompanying the printing operation. Count down.

  By continuing the printing operation without replacing with a new cartridge as it is, the value of the remaining amount counter 35 is set to a developer lower limit preset at a stage before the amount of developer replenishment from the hopper 103 to the developing tank decreases. The threshold is reached (T5: toner end). Then, the printing operation of the machine is stopped at this timing and the toner empty display is performed (state 10).

  In the present embodiment, when the remaining amount of developer stored in the hopper 103 during the continuous mode is reduced in the toner empty state, the printing operation is stopped before the developer supply amount to the developing tank 111 decreases. As a result, the toner density in the developer is gradually reduced, and the occurrence of image density reduction and carrier development (carrier adhesion) on the photosensitive drum 3 can be prevented.

  After the cartridge 22 is newly replaced, the remaining amount sensor 106 is judged to be low output, so that the developer conveying means starts to be transported from the cartridge 22 to the hopper 103, and eventually the remaining amount sensor 106 becomes judged to be high output. The conveyance of the developer to the hopper 103 is completed, and the state is shifted to a print operation enabled state (state 11). Then, the print job is resumed (T6: warm-up complete, job resume).

  During the subsequent printing operation, the operation in the hopper 103 is the same as that described above (state 4), and the remaining amount counter 35 indicates the screw rotation time in the hopper 103 during the printing operation and the remaining amount sensor output during the rotation. In response, the counter counts up (state 12).

  The value of the remaining amount counter 35 increases every time the toner replenishment operation is repeated, and eventually reaches a predetermined developer upper limit threshold (T7: hopper filling mode is completed), and is temporarily stored in the hopper 103. The maximum developer amount is reached (state 13).

  On the other hand, when the cartridge 22 is newly exchanged during the continuous mode (T8: cartridge exchange), as shown in FIG. 8, the continuous run mode is canceled and the value of the remaining amount counter 35 at the time of the exchange is determined. Thereafter, a positive correction coefficient is selected as the remaining amount counter correction coefficient for the screw rotation time, and as a result, the remaining amount counter 35 counts up (state 14).

  By the subsequent printing operation, the developer stored in the hopper 103 and the value of the remaining amount counter 35 eventually reach the predetermined developer upper limit threshold value after passing through (state 15) and are temporarily stored in the hopper 103. The maximum amount of developer that can be stored is reached again (T9: Hopper filling mode complete) (state 16).

  Further, when the developer amount in the hopper 103 and the value of the remaining amount counter 35 as shown in (State 15) before (State 16) are reached, when the cartridge door is opened (T10: Since the developer conveyance from the cartridge 22 is in a state where the developer conveyance is prohibited while the door is open (state 17), the count correction coefficient of the remaining amount counter 35 has a negative correction coefficient. As a result of the selection, the remaining amount counter 35 counts down with the printing operation (state 18).

  When the state where the cartridge door is opened continues, the value of the remaining amount counter 35 eventually reaches a preset developer lower limit threshold (T11: toner end). Then, the printing operation of the machine is stopped at this timing and the toner empty display is performed (state 19).

  Further, when the cartridge 22 is replaced with a cartridge in which the developer in the container has already been determined to be empty, the count calculation method of the remaining amount counter 35 is a negative correction coefficient as in the state in which the cartridge door is opened. Is selected, and the remaining amount counter 35 counts down with the printing operation.

  Next, a specific description will be given of control when the developer replenishing device 101 in the image forming apparatus 100 according to the present embodiment is malfunctioning or abnormal.

  In the image forming apparatus 100, when the developer replenishment apparatus 101 is controlled to be in trouble or abnormal, the toner empty determination by the remaining amount counter 35 is used when the developer replenishment apparatus 101 is operating normally. It is like that.

  In the image forming apparatus 100, the toner empty detection means mainly includes a magnetic permeability sensor 119 and a control device 32 as shown in FIG.

  The toner empty detection means of the developer supply device 101 monitors the toner concentration of the developer in the preliminary stirring portion R in the developing tank 111 with the toner supply detection sensor 119 and develops the developer supply device 101 by the control device 32. If the magnetic permeability sensor 119 cannot detect the supply of the developer after the instruction to supply the tank 111, it is determined that the developer is not supplied from the hopper 103 to the developer tank 111 (toner empty).

A power supply (not shown) is connected to the magnetic permeability sensor 119 shown in FIG.
This power supply applies a drive voltage for driving the magnetic permeability sensor 119 and a control voltage for outputting the detection result of the toner density to the control device 32 to the magnetic permeability sensor 119.
Application of a voltage to the magnetic permeability sensor 119 by the power source is controlled by the control device 32.

  The magnetic permeability sensor 119 is a type of sensor that receives a control voltage and outputs a toner density detection result as an output voltage value. The magnetic permeability sensor 119 basically has good sensitivity in the vicinity of the median value of the output voltage. Therefore, the magnetic permeability sensor 119 is used by applying a control voltage that can obtain an output voltage in the vicinity thereof.

  In this embodiment, the toner concentration of the developer in the developing tank 111 is monitored by the magnetic permeability sensor 119, and the magnetic permeability sensor 119 can detect the developer replenishment even after the controller 32 instructs the developer to be replenished. If not, it is determined that the developer supply device 101 is abnormal.

  A magnetic permeability sensor 119 is used to determine abnormality of the developer supply device 101 in the image forming apparatus 100.

When the toner concentration of the developer in the developing tank 111 decreases and falls below a predetermined value, the developer is supplied to the developing tank 111 from the control device 32 that controls the developer supply to the developer supplying apparatus 101. The developer is supplied from the hopper 103 to the developing tank 111.
The developer replenishment into the developing tank 111 is detected by the magnetic permeability sensor 119.

  For example, the magnetic permeability sensor 119 is disposed on the bottom surface of the first conveyance path below the toner supply port through which toner is supplied to the developing tank 111, and when the toner is supplied to the developing tank 111 from the toner supply port, A change in the magnetic permeability of the developer can be detected immediately. That is, it is possible to immediately confirm whether or not the toner supply by the developer supply device 101 has been performed.

Accordingly, when the control device 32 instructs the developer replenishing device 101 to replenish the developer, when the output difference due to the change in the toner density of the developer is not detected by the magnetic permeability sensor 119, the developer replenishing device. 101, it can be determined that the developer is not replenished.
That is, the empty detection means can immediately determine whether the developer supply device 101 has failed or is abnormal (toner empty).

  Thus, in the image forming apparatus 100, the developer replenishing device is provided by providing the magnetic permeability sensor 119 in the vicinity of the toner replenishing port of the developing device 2 and on the bottom surface of the first transport path below the toner replenishing port. It is possible to immediately detect that the magnetic permeability of the developer has changed when the developer is replenished by 101. Thereby, when a toner image is formed on the photosensitive drum 3, it is possible to suppress a decrease in image density due to a decrease in toner density and occurrence of carrier adhesion to the photosensitive drum 3.

  As described above, according to the present embodiment, in the developer supply device 101 mounted on the image forming apparatus 100, the first transport member 131 and the second transport member 131 are screw members that transport the developer into the hopper 103. The control device 32 includes a conveyance member 132 and a remaining amount sensor 106. The function of the control device 32 is to control the operation of the screw member according to the output of the remaining amount sensor 106 (developer conveyance control means), and the rotation time of the screw member. And a remaining amount counter 35 that functions as a count value (count value calculation means) that calculates the developer amount stored in the hopper 103 as a count value, or when there is no developer in the cartridge 22 or the cartridge 22 Amount of developer in the hopper 103 based on the count value when developer transport from the hopper 103 to the hopper 103 is prohibited By providing a function (printing operation determining means) for determining whether or not the printing operation can be continued, the developer amount in the hopper 103 is calculated using the remaining amount counter 35 so that the developer amount can be accurately grasped. Therefore, the timing of toner empty can be determined with high accuracy. Further, when the remaining amount counter reaches a preset threshold value, it is possible to prevent a decrease in the amount of developer replenished from the hopper 103 to the developing tank 111 by determining whether the printing operation can be continued or not. Therefore, it is possible to prevent image density reduction and carrier adhesion to the photoreceptor due to toner density reduction of the developer.

  According to this embodiment, the remaining amount of developer in the hopper 103 can be accurately grasped, so that it is prevented from being determined that the toner is empty even though the printing operation is still possible. It is possible to reduce the downtime of the machine by making the print operation ready state (continuous run mode) as long as possible, so it is possible to continue without stopping the print job until it is replaced with a new cartridge. It can be carried out.

  In the above-described embodiment, the example in which the configuration of the image forming apparatus according to the present invention is applied to the image forming apparatus 100 as illustrated in FIG. 1 has been described. However, the developing apparatus is configured by supplying toner with a developer supplying apparatus. As long as the image forming apparatus controls the toner density of the developer in the image forming apparatus, the image forming apparatus is not limited to the above-described image forming apparatus or copying machine, and can be developed to other image forming apparatuses. It is.

  As described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope not departing from the gist of the present invention are also included in the technical scope of the present invention.

1 Exposure unit (exposure equipment)
2 Developing device 3 Photosensitive drum 5 Charger (charging device)
8 Intermediate transfer belt unit (transfer device)
12 Fixing unit (fixing device)
22 Cartridge (developer container)
32 Control device 33 Dot counting device 35 Remaining amount counter 36 Image forming process unit 37 Paper transport unit 100 Image forming device 101 Developer replenishing device 102 Replenishing pipe 103 Hopper 104 Cartridge driving motor 105 Hopper driving motor 106 Remaining amount sensor 111 Developing tank 113a Toner supply port 113b Storage unit 113c Toner drop port 113d Partition plate 119 Magnetic permeability sensor 131 First conveying member (screw member)
132 Second conveying member (screw member)

Claims (7)

A replaceable developer container for containing the developer, a hopper for temporarily storing the developer supplied from the developer container, and a developer replenishing means for replenishing the developing device with the developer stored in the hopper. A developer replenishing device comprising control means for controlling the operation of the developer replenishing means,
In the hopper, as the developer replenishing means, the developer supplied from the developer container is temporarily stored, and a screw member that conveys the developer by a rotating operation, and the development supplied in the hopper Equipped with a remaining amount sensor for detecting the amount of the agent,
The control means includes
A function of controlling the operation of the screw member in accordance with the output of the remaining amount sensor;
A function of monitoring the rotation time of the screw member and calculating the amount of developer stored in the hopper as a count value;
When there is no developer in the developer container, or when developer transport from the developer container to the hopper is prohibited, the amount of developer in the hopper can be continuously printed based on the count value. A function to determine whether or not,
A developer replenishing device comprising:   The developer supply device according to claim 1, wherein the remaining amount sensor is provided at a position where the developer conveyed from the developer container into the hopper can be detected.   The calculation method of the count value is calculated using a positive coefficient when it is determined that the developer is present in the developer container with respect to the rotation time of the screw member in the hopper. 3. A negative coefficient is used for calculation when it is determined that there is no developer in the container and when developer conveyance from the developer container to the hopper is prohibited. The developer replenishing device according to 1.   The positive coefficient in the count value calculation method is calculated as (High positive coefficient)> (Low positive coefficient) by switching the output from the remaining amount sensor while the screw member is rotating between High and Low. The developer replenishing device according to any one of claims 1 to 3, wherein:   The developer in the developer container contains either a two-component developer composed of a toner and a carrier or a one-component developer composed only of a toner. The developer supply device according to any one of the above.   The control means has a function of counting dot data corresponding to image data to be transmitted to an exposure device that forms an electrostatic latent image on the surface of a photoreceptor provided in an image forming apparatus in which the developer supply device is used. 6. A function of instructing the developer replenishing unit to replenish developer to the developing device in accordance with the dot data, according to claim 1. Developer replenisher. A photosensitive member on which an electrostatic latent image is formed, a charging device that charges the surface of the photosensitive member, an exposure device that forms an electrostatic latent image on the surface of the photosensitive member, and a developer on the electrostatic latent image on the surface of the photosensitive member In an image forming apparatus for forming an image by an electrophotographic method, comprising: a developing device for supplying an image to form an image; and a developer supplying device for supplying a developer to the developing device.
An image forming apparatus using the developer replenishing device according to claim 1 as the developer replenishing device.

Images