Image forming apparatus of electrophotographic system

Abstract

To solve the problem in which: in an image forming apparatus configured to allow removable mounting of a first developer cartridge or a second developer cartridge configured to store a larger amount of developer than the first developer cartridge, when the remaining amount of developer is detected using a pixel counting system, the accuracy of detecting the remaining amount is unstable when a large capacity cartridge is mounted.SOLUTION: An image forming apparatus comprises a remaining amount detection device, and acquires a remaining amount through remaining amount detection using a pixel counting system when a small capacity cartridge is mounted and acquires the remaining amount through remaining amount detection based on both detection results from the pixel counting system and the remaining amount detection device when a large capacity cartridge is mounted. With the remaining amount detection using the pixel counting system when the small capacity cartridge is mounted and the remaining amount detection based on both detection results from the pixel counting system and the remaining amount detection device when the large capacity cartridge is mounted, the remaining amount of developer can be accurately detected for both cartridges.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus, such as a laser printer, a copying machine, or a facsimile machine, that uses an electrophotographic recording method. [Background technology]

[0002] Conventionally, there has been known an image forming apparatus in which a process cartridge that contains a replaceable developer is configured to determine when to replace the installed process cartridge. For example, an image forming apparatus has been disclosed that counts the number of dots printed on paper immediately after replacing the process cartridge, calculates the total amount of developer consumption from this number of dots and the amount of developer consumption required to form one dot, and determines that it is time to replace the process cartridge when the calculated total amount of developer consumption exceeds a threshold value (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2-39178 Summary of the Invention [Problem to be solved by the invention]

[0004] In an image forming apparatus that can accommodate any one of process cartridges with different initial developer filling amounts, if information related to the calculated developer consumption amount, such as the number of dots, is used to detect the remaining developer amount, it may be difficult to properly detect the remaining developer amount in a process cartridge with a large initial developer filling amount. This is because the error that occurs between the calculated developer consumption amount and the actual developer consumption amount, which varies depending on the printing conditions, tends to accumulate and become large in a process cartridge with a large initial developer filling amount.

[0005] Therefore, an object of the present invention is to provide an image forming apparatus and an image forming system that can accurately detect the remaining amount of developer for each process cartridge in an image forming apparatus that can accommodate process cartridges with different initial developer filling amounts. [Means for solving the problem]

[0006] In order to achieve the above object, the image forming apparatus described in claim 1 has a cartridge mounting portion configured to removably mount a first developer cartridge configured to contain developer or a second developer cartridge configured to contain more developer than the first developer cartridge, a specification detection device configured to detect whether the first developer cartridge or the second developer cartridge is mounted in the cartridge mounting portion, and a remaining amount detection device for detecting the remaining amount of developer in the developer cartridge mounted in the cartridge mounting portion, wherein the remaining amount of developer is detected using information from a pixel count method in the image forming apparatus, the specification detection device determines whether the first developer cartridge or the second developer cartridge is mounted in the cartridge mounting portion based on information from the specification detection device, and when the first developer cartridge is mounted in the cartridge mounting portion, the remaining amount of developer is detected using information from the pixel count method, and when the second developer cartridge is mounted in the cartridge mounting portion, the remaining amount of developer is detected based on both information from the pixel count method and information from the remaining amount detection device. [Effects of the Invention]

[0007] According to the present invention, in an image forming device in which cartridges with different developer capacities can be removably mounted, when a small-capacity cartridge is mounted, the remaining amount is detected using the pixel count method, and when a large-capacity cartridge is mounted, the remaining amount is detected based on the detection results of both the pixel count method and a remaining amount detection device, making it possible to accurately detect the remaining amount of developer in either cartridge. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 4 is a flowchart illustrating control of remaining toner amount detection in the first embodiment. [Figure 2] FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus in which a small-capacity cartridge is installed. [Figure 3] FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus in which a large-capacity cartridge is installed. [Figure 4] FIG. 2 is an overall view of the cartridge showing the configuration of the remaining amount detecting device. [Figure 5] FIG. 2 is a diagram illustrating a configuration of a remaining amount detection device. [Figure 6] 1 is a diagram illustrating the mechanism of a remaining amount detection device (light transmission type developer remaining amount detection). FIG. [Figure 7] FIG. 1 is a block diagram of an image forming apparatus. [Figure 8] FIG. 4 is a detailed flowchart illustrating the control of remaining toner amount detection in the first embodiment. [Figure 9] FIG. 10 is a flowchart illustrating control of remaining toner amount detection in the second embodiment. [Figure 10] FIG. 11 is a flowchart illustrating control of remaining toner amount detection in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Note that the following embodiments do not limit the invention according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0010] Example 1 (Overall configuration of image forming apparatus) 2 and 3, a cross-sectional view of the overall configuration of an image forming apparatus including a developing device of the present invention will be described.

[0011] The image forming apparatus A according to this embodiment is provided with a photoreceptor 1, a charging device 2 for charging the surface of the photoreceptor 1, an exposure device 3 for forming an electrostatic latent image corresponding to image data on the charged photoreceptor 1, a developing device 4 for developing the electrostatic latent image formed on the surface of the photoreceptor 1 with a developer, a transfer device 5 that contacts the photoreceptor 1 and transfers a toner image to a recording material P, and a fixing device 6 that heats and presses the recording material P to fix the toner image. The image forming apparatus A is also provided with a power supply (not shown) for applying a predetermined voltage to each of the charging device 2, developing device 4, transfer device 5, etc.

[0012] The photosensitive drum 1 is an image carrier in which a negatively chargeable organic photosensitive material is molded on a cylindrical cylinder. The photosensitive drum 1 has a diameter of 24 mm and is driven to rotate in a predetermined direction (clockwise in the drawing) at a predetermined process speed by a drive motor M attached to the image forming apparatus A. In this embodiment, the photosensitive drum 1 is driven to rotate at a process speed of 250 mm / sec.

[0013] The charging device 2 is a charging means in which the charging roller 2, to which a desired charging voltage is applied by a power source (not shown), contacts the rotating photosensitive drum 1 with a predetermined pressure, thereby uniformly charging the surface of the photosensitive drum 1 to a predetermined potential. In this embodiment, the photosensitive drum 1 is negatively charged by the charging roller 2. The potential charged by the charging device 2 is called the dark potential.

[0014] The exposure device 3 is an exposure means that performs exposure corresponding to image information input from an external device or a reading device. There are scanner units that scan the surface of the photosensitive drum 1 with a semiconductor laser, and LED exposure devices with an LED array in which multiple LEDs are arranged along the longitudinal direction of the photosensitive drum 1. In this embodiment, a scanner unit that scans with a semiconductor laser was used. The potential that decays to near ground potential when the exposure device exposes the photosensitive drum surface at a dark potential is called the bright potential. In other words, a so-called electrostatic latent image is formed by forming exposed and unexposed areas on the photosensitive drum in accordance with the image information.

[0015] The developing device 4 is a developing means including a storage section 8 that stores toner T as a developer, a developing roller 41 as a toner carrier that carries the toner T, a supply roller 42 that can supply toner T to the developing roller 41, and a developing blade 43 that regulates the amount of toner. The developing roller 41 and the supply roller 42 are rotatably supported by a developer container. The developing roller 41 is disposed at an opening of the developing device 4 so as to face the photosensitive drum 1. The supply roller 42 rotatably contacts the developing roller 41, and the toner T stored in the storage section 8 is applied to the surface of the developing roller 41 by the supply roller 42. The developing blade 43 is an elastic member that is bent against its elasticity and is disposed in contact with the developing roller 41. The toner carried on the surface of the developing roller 41 by the developing blade 43 forms a predetermined layer thickness and is transported to a developing section that faces the photosensitive drum 1.

[0016] The developing device 4 of this embodiment uses a contact development method. That is, a toner layer carried by the developing roller 41 carrying toner T comes into contact with the photosensitive drum 1 in a development section (development area) where the photosensitive drum 1 and the developing roller 41 face each other. A developing voltage is applied to the developing roller 41 by a power supply (not shown). Under the developing voltage, the toner carried by the developing roller 41 is transferred from the developing roller 41 to the drum surface in accordance with the potential of the surface of the photosensitive drum 1, and the electrostatic latent image on the photosensitive drum is developed into a toner image.

[0017] The toner T in this embodiment is, for example, a polymerized toner produced by a polymerization method, spherical with a particle size of 7 μm, and normally charged negatively. The toner T in this embodiment does not contain a magnetic component, and is a so-called non-magnetic one-component developer in which the toner T is carried on the developing roller 41 mainly by intermolecular forces and electrostatic forces (image forces). The one-component developer may contain additives (e.g., wax or silica particles) in addition to the toner particles to adjust the fluidity and charging performance of the toner T. Alternatively, a magnetic one-component developer containing a magnetic component or a two-component developer composed of a non-magnetic toner and a magnetic carrier may be used as the developer. When a magnetic developer is used, a cylindrical developing sleeve with a magnet disposed inside may be used as the developer carrier.

[0018] The transfer device 5 is a transfer means that transfers the toner image carried on the photosensitive drum 1 onto the recording material P by the transfer roller 5 to which a transfer voltage is applied from a power supply (not shown). The recording material P onto which the toner image has been transferred is transported to the fixing device 6.

[0019] The fixing device 6 is a fixing means of a thermal fixing type that fixes an image by heating and melting the toner on the recording material P. The fixing device 6 includes a fixing film, a fixing heater such as a ceramic heater that heats the fixing film, a thermistor that measures the temperature of the fixing heater, and a pressure roller that is pressed against the fixing film.

[0020] The recording material P that has passed through the fixing device 6 is discharged to the outside (outside the machine) of the image forming apparatus A by a pair of discharge rollers as a discharge means, and is loaded onto a discharge tray as a loading section formed on the top of the image forming apparatus A main body.

[0021] The toner T that remains on the photosensitive drum 1 without being transferred is removed from the photosensitive drum by a cleaning device 7 that is arranged downstream of the transfer roller 5 in the rotation direction of the photosensitive drum, and is accumulated in the cleaning device 7. Various configurations are possible for the cleaning device 7, but here we used a so-called cleaning blade configuration in which urethane rubber supported and fixed on a metal plate is brought into contact with the photosensitive drum in the counter direction to the rotation direction.

[0022] [Detailed configuration of the image formation system] In the image forming system according to this embodiment, a process cartridge B, which integrates a photosensitive drum 1, a charging roller 2, a cleaning blade 7, and a developing device 4, is mounted in the main body of an image forming apparatus A and used. Either a process cartridge BL (hereinafter referred to as the "small-capacity cartridge") equipped with a small-capacity type storage section 8L as an example of a first process cartridge shown in Fig. 2, or a process cartridge BH (hereinafter referred to as the "large-capacity cartridge") equipped with a large-capacity type storage section 8H as an example of a second process cartridge shown in Fig. 3, is mounted in the main body of the image forming apparatus A and used.

[0023] As shown in FIG. 2, the container 8L of the small-capacity cartridge BL is filled with toner T in an amount that allows printing of 3,000 sheets of A4-sized paper P at a print rate of 5%, for example.

[0024] As shown in Fig. 3, the storage section 8H of the large-capacity cartridge BH is formed so that its volume is larger than the volume of the storage section 8L of the small-capacity cartridge BL, and is therefore configured to store more toner T than the storage section 8L. As an example, the storage section 8H of the large-capacity cartridge BH is filled with an amount of toner T sufficient to print 12,000 sheets of A4-sized paper P at a print rate of 5%. Also, as shown in Fig. 4, the container that forms the storage section 8H is formed with a light-transmitting section 98 for detecting the amount of toner in the storage section 8H.

[0025] The image forming apparatus A includes an image forming section 3A, a paper feeding section 3B, a cartridge mounting section 3C, a remaining amount detecting device 9, and a control device 10.

[0026] As shown in FIGS. 2 and 3, either a small-capacity cartridge BL or a large-capacity cartridge BH is configured to be detachably mounted.

[0027] As shown in Fig. 4, the remaining amount detecting device 9 is a device for detecting the remaining amount of toner T in the large-capacity cartridge BH (in the storage section 8H) attached to the cartridge mounting section 3C, and is mainly configured with a light-emitting element 91 and a light-receiving element 92 arranged to detect light passing through a light-transmitting portion 98 of the large-capacity cartridge BH attached to the cartridge mounting section 3C. The light-emitting element 91 is an element for emitting light (see dashed line) through one of the light-transmitting portions 98 into the storage section 8H attached to the cartridge mounting section 3C, and the light-receiving element 92 is an element for receiving light emitted from the light-emitting element 91 and passing through the storage section 8H through the light-transmitting portion 98. The light-receiving element 92 outputs an output signal to the control device 10 according to the intensity of the received light.

[0028] [Configuration of remaining amount detection means] Next, the configuration of the light transmitting portion 98, which is a remaining amount detecting means provided in the developing device 4, will be described with reference to FIGS.

[0029] 4 and 5, a light-transmitting portion 98, which is a remaining amount detection means for detecting the remaining amount of toner T, is provided on the wall of the container 8H. A light-emitting element 91 and a light-receiving element 92, which are provided in the image forming apparatus main body, are disposed outside the container 8H. The light-transmitting portion 98 is integrally formed with a light-emitting side light-guiding portion 98a for guiding the detection light emitted from the light-emitting element 91 into the container 8H, and a light-receiving side light-guiding portion 98b for guiding the detection light that has passed through the container 8H to the light-receiving element 92. The light-emitting side light-guiding portion 98a has an incident portion 98c through which the detection light emitted from the light-emitting element 91 enters the light-emitting side light-guiding portion 98a, and a light-emitting side window 98d through which the detection light that has entered the light-emitting side light-guiding portion 98a exits into the container 8H. Similarly, the light-receiving side light guide 98b has a light-receiving side window 98e through which the detection light that has passed through the housing portion 8H enters the light-receiving side light guide 98b, and an exit portion 98f that emits the detection light that has entered the light-receiving side light guide 98b toward the light-receiving element 92. The light-emitting side window 98d and the light-receiving side window 98e are arranged opposite each other, and an optical path through which the detection light passes is formed between them. However, if the optical path is formed taking into consideration the refraction of light that occurs when light is irradiated from the light-emitting side window 98d and when it enters the light-receiving side window 98e, the configuration is not limited to the light-emitting side window 98d and the light-receiving side window 98e being arranged opposite each other.

[0030] [Method of detecting remaining amount] Next, a method of detecting remaining toner amount using the light-transmitting portion 98 will be described with reference to FIGS. 4 and 5. As shown in FIG. 4, when detecting remaining toner amount, detection light is emitted from the light-emitting element 91. The emitted detection light enters the incident portion 98c and is guided into the container 8H through the light-emitting side window 98d shown in FIG. 5. The detection light emitted from the light-emitting side window 98d then enters the opposing light-receiving side window 98e. At this time, an optical path is formed between the light-emitting side window 98d and the light-receiving side window 98e. The detection light incident from the light-receiving side window 98e then exits from the exit portion 98f toward the light-receiving element 92 and is received by the light-receiving element 92. Based on the output of the light-receiving element 92, the toner remaining amount detection unit 101 of the control device 10 detects that the detection light has passed through the container 8H.

[0031] Here, the mechanism of light transmission type developer remaining amount detection in this embodiment will be described. FIG. 6(a) is a cross-sectional view showing the light transmission portion 98 when there is no toner T, and FIG. 6(b) is a cross-sectional view showing the state when toner T is passing through the light transmission portion 98. While toner T is not present in the light transmission portion 98, an optical path is formed. However, as shown in FIG. 6(b), while toner T is passing through the light transmission portion, the optical path is blocked by the toner T, and the detection light is not detected by the light receiving element 92. Then, as shown in FIG. 6(a), once the toner T has passed through, the optical path is formed again, and the detection light is detected by the light receiving element 92. When the amount of remaining toner in the storage portion 8H is large, the amount of toner T passing through the light transmission portion 98 is large and the passage time is long, so the time the optical path is blocked is also long. On the other hand, when the amount of remaining toner is low, the amount of toner T passing through the light transmission portion 98 is small and the passage time is short, so the time the optical path is blocked is also short. In this way, the length of time that the light receiving element 92 can receive light changes depending on the amount of toner remaining in the storage section 8H, so that the remaining amount of toner T can be detected by the detection unit 101 from the time when the detection light is blocked based on the output of the light receiving element 92.

[0032] FIG. 7 is a block diagram of an image forming apparatus. The control device 10 includes a CPU, RAM, ROM, an input / output interface, and the like (not shown), and is configured to control the operation of the image forming apparatus A by controlling each component of the image forming apparatus A. Specifically, in this embodiment, the control device 10 controls the image forming unit 3A and the paper feed unit 3B to form an image on a recording material P when a job including a print command and image data for the image to be formed is input from an external device Z, such as a personal computer or digital camera. Furthermore, in this embodiment, the control device 10 detects the amount of toner remaining in the accommodating unit 8 (8L, 8H) of the process cartridge B (BL, BH) installed in the cartridge mounting unit 3C, and controls a display unit (not shown) to display a message urging the user to replace the process cartridge B or to indicate the amount of toner remaining.

[0033] In order to perform the above-described control, the control device 10 of this embodiment mainly has an image formation control unit 103, an attachment determination unit 102, and a toner remaining amount detection unit 101 as functional units, as shown in FIG.

[0034] The mounting determination unit 102 is a functional unit for determining whether the process cartridge BL or the process cartridge BH is mounted in the cartridge mounting unit 3C. In this embodiment, as shown in Fig. 7, the process cartridge B is provided with an IC chip M in which specification information (such as whether it is a small-capacity cartridge BL or a large-capacity cartridge BH) is pre-stored, and the mounting determination unit 102 is configured to determine whether the small-capacity cartridge BL or the large-capacity cartridge BH is mounted based on information input from a device that reads the information on the IC chip M.

[0035] The remaining toner amount detection unit 101 is a functional unit for detecting the amount of toner remaining in the accommodating unit 8 of the process cartridge B mounted in the cartridge mounting unit 3C, and has a detection unit A that detects the amount of toner remaining using a pixel count method, and a detection unit B that directly detects the amount of toner remaining in the accommodating unit 8 based on input information from the remaining toner amount detection device 9. In this embodiment, the remaining toner amount detection unit 101 is configured to change the method of detecting the amount of toner remaining depending on the specifications of the process cartridge B mounted in the cartridge mounting unit 3C, i.e., depending on whether a small-capacity cartridge BL or a large-capacity cartridge BH is mounted.

[0036] As shown in the flowchart of FIG. 1, in this embodiment, it is detected whether the process cartridge B attached to the image forming apparatus A is a large-capacity cartridge BH or a small-capacity cartridge BL (S1), and if it is a small-capacity cartridge BL ("No" in S1), the remaining toner amount is detected using a pixel count method.

[0037] On the other hand, in the case of the large-capacity cartridge BH ("Yes" in S1), the remaining toner amount is detected using information A of remaining toner amount detection by the pixel count method and information B of remaining toner amount detection from the remaining toner amount detection device.

[0038] Specifically, as shown in Fig. 2, when a small-capacity cartridge BL is mounted in the cartridge mounting portion 3C, the toner remaining amount detection unit 101 acquires information related to the amount of toner consumed based on image data input after the process cartridge B is mounted, and detects the amount of toner remaining in the process cartridge B using a pixel count method. More specifically, in this embodiment, the information related to the amount of toner consumed is the integrated value of the number of dots in an image to be formed on the recording material P, and can be acquired, for example, by integrating the number of dots acquired based on information for driving a laser light source (not shown) of the exposure device 3, which is included in image data input from an external device Z, each time image data is input. The toner remaining amount detection unit 101 (detection unit A) then detects the amount of toner remaining in the small-capacity cartridge BL using the integrated value ND of the acquired number of dots and a preset threshold value table or conversion table related to the number of dots.

[0039] On the other hand, as shown in Figure 3, when the large-capacity cartridge BH is mounted in the cartridge mounting portion 3C, the toner remaining amount detection unit 101 detects the remaining amount of toner in the process cartridge B by combining two pieces of information: information from detection unit A, which detects the remaining amount of toner using a pixel count method based on image data, and information from detection unit B, which is input from the light receiving element 92 of the remaining amount detection device 9 (see Figure 4).

[0040] Explain in detail.

[0041] In detection unit A, there may be a discrepancy between the actual amount of developer consumed and the calculated amount of developer consumed due to the influence of printing conditions such as the usage environment. On the other hand, detection unit B directly detects the amount of toner in storage unit 8, and therefore has higher detection accuracy than detection unit A. Therefore, it is conceivable to configure the display of the remaining toner amount to switch from remaining toner amount A detected by detection unit A to remaining toner amount B detected by detection unit B within the range where detection unit B can detect the amount of toner in storage unit 8. In this case, it is conceivable that a more accurate remaining toner amount can be displayed.

[0042] However, there may be a difference in the remaining toner amount value between the amount of toner detected by detection unit A and the amount of toner detected by detection unit B. Therefore, if the value used to display the remaining toner amount is switched from detection unit A to detection unit B, there is a risk that the displayed amount of remaining toner may suddenly change. Therefore, in this embodiment, detection unit A remains the detection unit used to display the remaining toner amount, and the remaining toner amount calculated by detection unit A based on the detection results of detection unit B gradually matches the remaining toner amount detected by detection unit B. In other words, in this embodiment, the remaining toner amount calculated by detection unit A is corrected based on the information from detection unit B.

[0043] The correction method will be described. If the amount of remaining toner calculated by detection unit A is greater than the amount of remaining toner detected by detection unit B, detection unit A will calculate that less toner has been consumed than the amount of toner actually consumed. Therefore, in this embodiment, the amount of toner consumed (calculated value) calculated by detection unit A is corrected to be larger.

[0044] Conversely, if the amount of remaining toner calculated by detection unit A is less than the amount of remaining toner detected by detection unit B, detection unit A will calculate that more toner has been consumed than actually consumed. Therefore, in this case, the amount of toner consumed calculated by detection unit A will be corrected to be less than the calculated amount.

[0045] Next, a flow of calculating the amount of toner in the storage unit 8 will be described. Fig. 7 is a block diagram showing the hardware configuration of the image forming apparatus A according to the first embodiment. Fig. 8 is a more detailed flowchart showing the flow of detecting the remaining amount of toner in the first embodiment.

[0046] In this embodiment, the detection unit A detects the remaining toner amount A (%) using the formula A (%) = A1 (%) - K × ΔA (%). The remaining toner amount A (%) is the amount of toner remaining in the developer container after the current image forming operation has been performed. The remaining toner amount A1 (%) is the amount of toner remaining in the developer container after the previous image forming operation has been performed. The toner consumption amount ΔA (%) is the amount of toner consumed in the current image forming operation, and is the amount of toner consumed detected by the detection unit A. The coefficient K is a correction coefficient for increasing or decreasing the toner consumption amount ΔA (%). In this embodiment, the coefficient K is increased or decreased to correct the amount of toner consumed in one (current) image forming operation, thereby gradually bringing the value of the remaining toner amount A (%) closer to the value of the remaining toner amount B (%).

[0047] S102: When the process cartridge B is mounted in the image forming apparatus A, the control device 10 determines whether the small-capacity cartridge BL or the large-capacity cartridge BH is mounted based on the information input from the device that reads the information on the IC chip M.

[0048] If it is a small capacity cartridge, go to No. If it is a large capacity cartridge, go to Yes. S103: The control device 10 sets the value of the remaining toner amount A1 stored in the IC chip M as the remaining toner amount A1 (%). At this time, if the process cartridge B is unused, the remaining toner amount A1 (%) in the process cartridge B is set to 100 (%). The control device 10 controls the display means, and the display means displays the remaining toner amount A1 (%) in the process cartridge B.

[0049] S104: When preparation for the image forming operation is completed and a command for the image forming operation is issued, the image forming operation is started. S105: The control device 10 controls the detection unit A to detect the toner consumption amount ΔA (%) consumed in the current image forming operation. The method for detecting the toner consumption amount ΔA (%) is as described above. S106: The control device 10 detects the remaining toner amount B by the detection unit B. S107: The remaining toner amount B (%) detected by the detection unit B is compared with a threshold value (first correction coefficient review timing) B0. In this embodiment, the threshold value B0 is 40 (%).

[0050] If the detected value B is greater than the threshold value B0, proceed to No. If the detected value B is equal to or less than the threshold value B0, proceed to Yes.

[0051] S108: The control device 10 compares the remaining toner amount A1 (%) detected by the detection unit A (the remaining toner amount A1 (%) is the remaining toner amount after the previous image forming operation) with the remaining toner amount B (%) detected by the detection unit B. S109: This is a step for determining the value of the coefficient K. The value of the coefficient K is selected based on the determinations in S102 and S107 and the comparison results in S108.

[0052] Details for each decision are provided below. When S102 is "No".

[0053] If it is determined that the cartridge is not a large-capacity cartridge BH (i.e., a small-capacity cartridge BL), the process proceeds to S1031, S1041, and S1051, where the coefficient K is set to 1 to calculate the remaining toner amount detection value A in S110. In other words, if the cartridge is a small-capacity cartridge BL, the remaining toner amount is detected based only on the image data information.

[0054] When S102 is "Yes" and S107 is "No". If it is determined to be a large-capacity cartridge, and the detection value B of the remaining amount detection mechanism is greater than the threshold value B0, the coefficient K is set to 1 to calculate the remaining toner amount detection value A in S110. In other words, if it is a large-capacity cartridge BH and the detection value B is greater than the threshold value B0, the remaining toner amount is detected based only on the image data information.

[0055] When S102 is "Yes" and S107 is "Yes". If it is determined to be a large-capacity cartridge, when the detection value B of the remaining toner amount detection mechanism falls below the threshold value B0, the value of coefficient K is reset based on a comparison between detection value A1 and detection value B, and the toner remaining amount detection value A in S110 is corrected and calculated.

[0056] When remaining toner amount A1 = remaining toner amount B, it can be determined that the toner consumption amount ΔA (%) during image formation operation is equal to the actual consumption amount. In this case, no correction is made by detection unit B. The value of coefficient K in the formula A (%) = A1 (%) - K × ΔA (%) to calculate remaining toner amount A (%) is set to 1 (K = 1).

[0057] When remaining toner amount A1 is greater than or equal to remaining toner amount B, it can be determined that the amount of toner consumed ΔA (%) during image formation is detected as less than the actual amount consumed. Therefore, a coefficient K of K = 1.2 is set. Since remaining toner amount A1 (%) is greater than or equal to remaining toner B (%), the coefficient K is always 1 or greater. By doing so, the value of remaining toner amount A (%) (= A1 (%) - K × ΔA (%)) becomes smaller than when coefficient K is 1. Therefore, the value of remaining toner amount A (%) approaches the value of remaining toner B (%).

[0058] When remaining toner amount A1 is less than or equal to remaining toner amount B, it can be determined that the detected toner consumption amount ΔA (%) during image formation is greater than the actual consumption amount. Therefore, a coefficient K of K = 0.85 is set. Because remaining toner amount B (%) is greater than remaining toner amount A1 (%), coefficient K is always less than 1. This makes the value of remaining toner amount A (%) (= A1 (%) - K × ΔA (%)) greater than when coefficient K is 1. Therefore, the value of remaining toner amount A (%) approaches the value of remaining toner B (%). Furthermore, by using this formula, the greater the difference between remaining toner amount B (%) and remaining toner amount A1 (%), the smaller the value of coefficient K becomes, and the value of remaining toner A (%) approaches the value of remaining toner B (%).

[0059] S110: The control device 10 calculates the remaining toner amount A (%) using the formula A (%) = A1 (%) - K × ΔA (%). The remaining toner amount A (%) acquired by the detection unit A is stored in the IC chip M and is used as the remaining toner amount A1 when detecting the remaining toner amount A (%) in the next image forming operation.

[0060] S111: The remaining toner amount A is displayed on the display unit. S112: Toner remaining amount detection operation is completed. If image formation operation is to be performed subsequently, the process returns to S103.

[0061] As described above, according to this embodiment, even in an image forming device that can be used by installing any one of process cartridges with different initial toner filling amounts, it is possible to accurately notify the user of the remaining toner amount in each process cartridge.

[0062] In this embodiment, the values ​​K=1.20 or K=0.85 are used, but the values ​​are not necessarily limited to these. The coefficient K is not particularly limited, and the coefficient K may be determined using a calculation formula.

[0063] In this embodiment, in steps S104 and S105 of the flowchart, the threshold value B0 is used to determine whether or not to perform correction by the detection unit B, but this is not necessarily limited to this. For example, when the remaining toner amount A (%) (A1 (%)) detected by the detection unit A reaches a predetermined value, correction of the remaining toner amount A using the detection unit B may be started.

[0064] <Example 2> In this embodiment, the greater the difference between detection value A1 and detection value B detected by the remaining toner amount detection mechanism, the stronger the correction applied to the calculation result of detection unit A. In this embodiment, the value of correction coefficient K is determined by a formula depending on the magnitude of the difference in the remaining toner amount between detection unit A1 and detection unit B, making it possible to display a more accurate remaining toner amount.

[0065] In this example, the formula for calculating the coefficient K is

[0066]

number

[0067] The other configurations are the same as those in the first embodiment. FIG. 9 shows a flowchart of the second embodiment.

[0068] S202: When the process cartridge B is mounted in the image forming apparatus A, the control device 10 determines whether the small-capacity cartridge BL or the large-capacity cartridge BH is mounted based on the information input from the device that reads the information on the IC chip M.

[0069] If it is a small capacity cartridge, go to No. If it is a large capacity cartridge, go to Yes. S203: The control device 10 sets the value of the remaining toner amount A1 stored in the IC chip M as the remaining toner amount A1 (%). At this time, if the process cartridge B is unused, the remaining toner amount A1 (%) in the process cartridge B is set to 100 (%). The control device 10 controls the display means, and the display means displays the remaining toner amount A1 (%) in the process cartridge B.

[0070] S204: When preparation for the image forming operation is completed and a command for the image forming operation is issued, the image forming operation is started.

[0071] S205: The control device 10 controls the detection unit A to detect the toner consumption amount ΔA (%) consumed in the current image forming operation. The method for detecting the toner consumption amount ΔA (%) is the same as in the first embodiment.

[0072] S206: The control device 10 detects the remaining toner amount B by the detection unit B. S207: The remaining toner amount B (%) detected by the detection unit B is compared with the threshold value (first correction coefficient review timing) B0. The threshold value B0 is 40 (%), as in the first embodiment. If the detected value B is greater than the threshold value B0, proceed to No. If the detected value B is equal to or less than the threshold value B0, proceed to Yes.

[0073] S208: The control device 10 compares the remaining toner amount A1 (%) detected by the detection unit A (the remaining toner amount A1 (%) is the remaining toner amount after the previous image forming operation) with the remaining toner amount B (%) detected by the detection unit B.

[0074] S209: This is a step for determining the value of the coefficient K. The value of the coefficient K is selected based on the determinations in S202 and S207 and the comparison results in S208. Details for each decision are provided below. When S202 is "No".

[0075] If it is determined that the cartridge is not a large-capacity cartridge BH (i.e., a small-capacity cartridge BL), the process proceeds to S2031, S2041, and S2051, where the coefficient K is set to 1 and the remaining toner amount detection value A is calculated in S209. In other words, if the cartridge is a small-capacity cartridge BL, the remaining toner amount is detected based only on the image data information.

[0076] When S202 is "Yes" and S207 is "No". If it is determined to be a large-capacity cartridge, and the detection value B of the remaining amount detection mechanism is greater than the threshold value B0, the coefficient K is set to 1 to calculate the remaining toner amount detection value A in S209. In other words, if it is a large-capacity cartridge BH and the detection value B is greater than the threshold value B0, the remaining toner amount is detected based only on the image data information.

[0077] When S202 is "Yes" and S207 is "Yes". If it is determined to be a large-capacity cartridge, when the detection value B of the remaining toner amount detection mechanism falls below the threshold value B0, the value of coefficient K is reset based on a comparison between detection value A1 and detection value B, and the toner remaining amount detection value A in S2090 is corrected and calculated.

[0078] In this embodiment, the coefficient K is calculated using the formula (1). S209: The control device 10 calculates the remaining toner amount A (%) using the formula A (%) = A1 (%) - K × ΔA (%). The remaining toner amount A (%) acquired by the detection unit A is stored in the IC chip M and is used as the remaining toner amount A1 when detecting the remaining toner amount A (%) in the next image forming operation.

[0079] S210: The remaining toner amount A is displayed on the display unit. S211: The remaining toner amount detection operation is completed. If an image forming operation is to be performed subsequently, the process returns to S103.

[0080] By adopting the above-described configuration, it is possible to accurately notify the user of the remaining toner amount in each process cartridge even in an image forming device that can be used by installing any one of process cartridges having different initial toner filling amounts, as in Example 1.

[0081] Example 3 In this embodiment, the range of the remaining toner amount for which correction with the coefficient K based on the detection value B of the remaining amount detection device 9 is performed is limited.

[0082] Specifically, the coefficient K is corrected when the detection value B of the remaining amount detection device 9 is in the range of 70%≧detection value B≧10%.

[0083] The remaining amount detecting device 9 used in this embodiment is configured to be able to accurately detect the remaining amount of toner in the range of 80%≧detection value B≧5%.

[0084] This is because, in the case of the optical developer detection device used in this embodiment, when the amount of toner in the container is sufficiently large or very small, the time it takes for the light receiving element 92 to receive light becomes unstable. Therefore, correction is made using the coefficient K based on the detection value B of the remaining amount detection device 9 in the range of 70%≧detection value B≧10%, where the detection accuracy of the detection value B is good.

[0085] The other configurations are the same as those in the first embodiment. FIG. 10 shows a flowchart of this embodiment.

[0086] S302: When the process cartridge B is mounted in the image forming apparatus A, the control device 10 determines whether the small-capacity cartridge BL or the large-capacity cartridge BH is mounted based on the information input from the device that reads the information on the IC chip M.

[0087] If it is a small capacity cartridge, go to No. If it is a large capacity cartridge, go to Yes. S303: The control device 10 sets the value of the remaining toner amount A1 stored in the IC chip M as the remaining toner amount A1 (%). At this time, if the process cartridge B is unused, the remaining toner amount A1 (%) in the process cartridge B is set to 100 (%). The control device 10 controls the display means, and the display means displays the remaining toner amount A1 (%) in the process cartridge B.

[0088] S304: When preparation for the image forming operation is completed and a command for the image forming operation is issued, the image forming operation is started.

[0089] S305: The control device 10 controls the detection unit A to detect the toner consumption amount ΔA (%) consumed in the current image forming operation. The method for detecting the toner consumption amount ΔA (%) is the same as in the first embodiment described above.

[0090] S306: The control device 10 detects the remaining toner amount B by the detection unit B. S307: Determine whether the remaining toner amount B (%) detected by the detection unit B is within a preset range. In this embodiment, 10%≦B≦70%.

[0091] If detected value B is outside the set value range, proceed to No; if detected value B is within the range, proceed to Yes. S308: The control device 10 compares the remaining toner amount A1 (%) detected by the detection unit A (the remaining toner amount A1 (%) is the remaining toner amount after the previous image forming operation) with the remaining toner amount B (%) detected by the detection unit B.

[0092] S309: This is a step for determining the value of the coefficient K. The value of the coefficient K is selected based on the determinations in S302 and S307 and the comparison results in S308.

[0093] Details for each decision are provided below. When S302 is "No". If it is determined that the cartridge is not a large-capacity cartridge BH (i.e., a small-capacity cartridge BL), the process proceeds to S3031, S3041, and S3051, where the coefficient K is set to 1 and the remaining toner amount detection value A is calculated in S310. In other words, if the cartridge is a small-capacity cartridge BL, the remaining toner amount is detected based only on the image data information.

[0094] When S302 is "Yes" and S307 is "No". If it is determined to be a large-capacity cartridge, and the detection value B of the remaining amount detection mechanism is outside the set value range, the coefficient K is set to 1 to calculate a remaining toner amount detection value A of 310. In other words, for large-capacity cartridge BH, when the detection value B is more than 70% or less than 10%, the remaining toner amount is detected based only on image data information.

[0095] When S302 is "Yes" and S307 is "Yes". If it is determined to be a large-capacity cartridge, and the detection value B of the remaining toner amount detection mechanism is 10%≦B≦700%, the value of coefficient K is reset based on a comparison between detection value A1 and detection value B, and the toner remaining amount detection value A in S310 is corrected and calculated.

[0096] When remaining toner amount A1 = remaining toner amount B, it can be determined that the toner consumption amount ΔA (%) during image formation operation is equal to the actual consumption amount. In this case, no correction is made by detection unit B. The value of coefficient K in the formula A (%) = A1 (%) - K × ΔA (%) to calculate remaining toner amount A (%) is set to 1 (K = 1).

[0097] When remaining toner amount A1 is greater than or equal to remaining toner amount B, it can be determined that the amount of toner consumed ΔA (%) during image formation is detected as less than the actual amount consumed. Therefore, a coefficient K of K = 1.2 is set. Since remaining toner amount A1 (%) is greater than or equal to remaining toner B (%), the coefficient K is always 1 or greater. By doing so, the value of remaining toner amount A (%) (= A1 (%) - K × ΔA (%)) becomes smaller than when coefficient K is 1. Therefore, the value of remaining toner amount A (%) approaches the value of remaining toner B (%).

[0098] When remaining toner amount A1 is less than or equal to remaining toner amount B, it can be determined that the detected toner consumption amount ΔA (%) during image formation is greater than the actual consumption amount. Therefore, a coefficient K of K = 0.85 is set. Because remaining toner amount B (%) is greater than remaining toner amount A1 (%), coefficient K is always less than 1. This makes the value of remaining toner amount A (%) (= A1 (%) - K × ΔA (%)) greater than when coefficient K is 1. Therefore, the value of remaining toner amount A (%) approaches the value of remaining toner B (%). Furthermore, by using this formula, the greater the difference between remaining toner amount B (%) and remaining toner amount A1 (%), the smaller the value of coefficient K becomes, and the value of remaining toner A (%) approaches the value of remaining toner B (%).

[0099] S310: The control device 10 calculates the remaining toner amount A (%) using the formula A (%) = A1 (%) - K × ΔA (%). The remaining toner amount A (%) acquired by the detection unit A is stored in the IC chip M and is used as the remaining toner amount A1 when detecting the remaining toner amount A (%) in the next image forming operation.

[0100] S311: The remaining toner amount A is displayed on the display unit. S312: The remaining toner amount detection operation is completed. If an image forming operation is to be performed subsequently, the process returns to S303.

[0101] As described above, according to this embodiment, as in Example 1, even in an image forming device that can be used by installing any one of process cartridges with different initial toner filling amounts, it is possible to accurately notify the user of the remaining toner amount in each process cartridge.

[0102] In the described embodiments 1 to 3, the remaining amount detection device 9 is configured as a light-transmitting type developer remaining amount detection device using a light-emitting element 91 and a light-receiving element 92, but the remaining amount detection device 9 may also use a capacitance type or a weight detection type. [Explanation of symbols]

[0103] 1 Photosensitive body (photosensitive drum) 2. Charging device (charging roller) 3 Exposure equipment 4. Developing device 4H developing device 4L developing device 41 Developing roller 42 Supply roller 43 Regulatory Blade 5. Transfer device 6 Fixing device 7 Cleaning Device 8 Storage section 8H storage section 8L storage compartment A Image forming device B Process cartridge BL Process cartridge with a small-capacity type storage compartment (small-capacity cartridge) BH Process cartridge with a large-capacity type storage compartment (large-capacity cartridge) 10 Control device 101 Toner remaining amount detection unit Detection unit A detects the remaining amount of toner based on information on toner consumption Detector B: Detects remaining amount based on information from remaining amount detector 102 Wearing judgment unit 103 Image formation control unit M IC chip P Recording sheet (recording material) 3A Image forming section 3B Paper feed section 3C Cartridge Device 9 Remaining amount detection device 91 Light-emitting element 92 Photodetector 98 Light transmission part 98a Light-emitting side light guide section 98b Light receiving side light guide section 98c entrance section 98d Illuminating side window 98e Light receiving side window 98f Emitter Z External device T Toner

Claims

1. an image forming apparatus having a cartridge mounting portion configured to detachably mount a first developer cartridge configured to accommodate a developer or a second developer cartridge configured to accommodate a larger amount of developer than the first developer cartridge; a specification detection device configured to detect whether the first developer cartridge or the second developer cartridge is mounted in the cartridge mounting portion; and a remaining amount detection device for detecting the remaining amount of developer in the developer cartridge mounted in the cartridge mounting portion, wherein the remaining amount of developer is detected using information obtained by a pixel count method; determining whether the first developer cartridge or the second developer cartridge is mounted in the cartridge mounting portion based on information from the specification detection device; When the first developer cartridge is mounted in the cartridge mounting portion, the remaining amount of developer is detected using information obtained by a pixel count method; An image forming apparatus characterized in that, when the second developer cartridge is attached to the cartridge attachment portion, developer remaining amount detection is performed based on both information obtained by a pixel count method and information obtained by the remaining amount detection device.

2. 2. The developer cartridge according to claim 1, wherein the remaining amount detecting device is a light-transmitting type developer remaining amount detecting device, and the second developer cartridge has a transparent portion used for the light-transmitting type developer remaining amount detecting device.

3. 2. The developer cartridge according to claim 1, wherein the remaining amount detecting device detects the remaining amount of developer by a capacitance method, and the second developer cartridge is provided with an antenna member used for detecting the remaining amount of developer.

4. An image forming apparatus according to any one of claims 1 to 3, characterized in that, when the second developer cartridge is installed, the remaining amount detection value obtained by the pixel count method is corrected based on information from the remaining amount detection device.

Images