Image-forming device, toner remaining amount detection device, and toner remaining amount detection method

Abstract

To accurately detect the remaining amount of toner regardless of the remaining amount within a toner vessel and deviation of toner in an image-forming device.SOLUTION: An image-forming device 100 includes a toner remaining amount detection device 200 for detecting a toner remaining amount W within a toner cartridge 32A as one example of a toner vessel 32 for housing toner. The toner remaining amount detection device 200 includes: a tuning fork 210 installed so as to receive a load from the toner cartridge 32A; a vibration detection section 220 for detecting vibration of the tuning fork 210 because of a load; and a control section 230 for estimating the toner remaining amount W. The control section 230 acquires a first oscillation frequency f1 resonating with the toner cartridge 32A before starting a print job, and a second oscillation frequency f2 resonating with the toner cartridge 32A after completion of a print job, and estimates the toner remaining amount W by using a difference between the first oscillation frequency f1 and the second oscillation frequency f2.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus, a toner remaining amount detecting device, and a toner remaining amount detecting method. [Background technology]

[0002] 2. Description of the Related Art Techniques for detecting the amount of toner remaining in a toner container in an image forming apparatus are known.

[0003] Patent Document 1 discloses a configuration in which, for the purpose of detecting the amount of toner remaining in a toner bottle, parallel plate electrodes are provided above, below, left and right of the toner bottle, and the amount of toner remaining is detected by electrostatic capacitance. Summary of the Invention [Problem to be solved by the invention]

[0004] However, with conventional methods for detecting remaining toner, such as those disclosed in Patent Document 1, when the amount of toner in the bottle becomes low, the amount of remaining toner may not be detected accurately due to reasons such as the inside of the bottle being filled with substances other than toner, such as air, or the limited space around the toner bottle making it impossible to install multiple parallel plate electrodes.

[0005] SUMMARY OF THE DISCLOSURE An object of the present invention is to enable accurate detection of the amount of remaining toner in an image forming apparatus, regardless of the amount of remaining toner in a toner container or uneven distribution of toner. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, an image forming apparatus according to one aspect of the present invention comprises a toner container for storing toner, an image creating unit to which the toner stored in the toner container is supplied to form a toner image, and a toner remaining amount detection unit for detecting the remaining amount of toner in the toner container, wherein the toner remaining amount detection unit has a tuning fork installed to receive a load from the toner container, a vibration detection unit for detecting vibration of the tuning fork due to the load, and a control unit for estimating the remaining amount of toner based on the vibration, and the control unit obtains a first vibration frequency that resonates with the toner container before the start of a print job and a second vibration frequency that resonates with the toner container after the print job is completed, and estimates the remaining amount of toner using the difference between the first vibration frequency and the second vibration frequency. Effect of the Invention

[0007] In an image forming apparatus, the amount of remaining toner can be accurately detected regardless of the amount of remaining toner in a toner container or uneven distribution of toner. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of an overall configuration of an image forming apparatus. [Diagram 2] FIG. 2 is a diagram showing an example of the configuration of an image forming unit; [Diagram 3] FIG. 1 is a diagram showing a schematic configuration of a toner remaining amount detection device according to a first embodiment; [Figure 4] Hardware configuration diagram of the control unit in Figure 3 [Diagram 5] Functional block diagram of a control unit according to the first embodiment [Figure 6] Flowchart of remaining toner amount detection control according to the first embodiment [Figure 7] 11 is a flowchart showing a modified example of remaining toner amount detection control. [Figure 8] FIG. 13 is a diagram showing a schematic configuration of a toner remaining amount detection device according to a second embodiment; [Figure 9] FIG. 13 is a plan view showing a schematic configuration of a toner remaining amount detection device according to a third embodiment; [Figure 10]FIG. 13 is a side view showing a schematic configuration of a toner remaining amount detection device according to a third embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components in each drawing are denoted by the same reference numerals as much as possible, and duplicated description will be omitted.

[0010] [First embodiment] A first embodiment will be described with reference to Figures 1 to 6. An image forming apparatus 100 according to this embodiment includes a toner remaining amount detection device 200 that detects the amount of toner remaining in a toner container 32.

[0011] <Basic configuration of image forming apparatus> First, the basic configuration of an image forming apparatus 100 according to this embodiment will be described with reference to FIGS.

[0012] Fig. 1 is a diagram showing an example of the overall configuration of an image forming apparatus 100. As shown in Fig. 1, the image forming apparatus 100 has a toner container storage section 70, an intermediate transfer unit 15, an imaging section 6, and a toner supply section 60. Four toner containers 32 (Y, M, C, K) corresponding to the respective colors (yellow, magenta, cyan, black) are detachably (replaceably) installed in the toner container storage section 70.

[0013] 1, an intermediate transfer unit 15 is provided below the toner container storage unit 70. Image forming units 6 (Y, M, C, K) corresponding to each color are arranged in parallel to face the intermediate transfer belt 8 of the intermediate transfer unit 15.

[0014] Further, toner supply units 60 (Y, M, C, K) are provided below the toner containers 32 (Y, M, C, K), respectively. The toner contained in the toner containers 32 (Y, M, C, K) is supplied (replenished) into the developing units 5 (see FIG. 2) of the imaging units 6 (Y, M, C, K) by the toner supply units 60 (Y, M, C, K), respectively.

[0015] The four toner containers 32 (Y, M, C, K) corresponding to the respective colors, the imaging units 6 (Y, M, C, K) and the toner supply units 60 (Y, M, C, K) have the same configuration except that they use different colors of toner. Therefore, in the following explanation and drawings, the suffixes "Y", "M", "C", and "K" indicating the colors of toner used will be omitted as appropriate.

[0016] Fig. 2 is a diagram showing an example of the configuration of the image forming unit 6 according to the embodiment. Fig. 2 shows an example of the configuration of one of the four image forming units 6 in Fig. 1.

[0017] The image forming unit 6 has a photoconductor 1, a charging unit 4 provided around the photoconductor 1, a developing unit 5, a cleaning unit 2, and a charge removing unit. Then, an image forming process, that is, a charging step, an exposure step, a developing step, a transfer step, and a cleaning step, is performed on the photoconductor 1, and an image of each color is formed on the photoconductor 1.

[0018] The photoconductor 1 is rotated by a drive motor in the direction of the arrow shown on the photoconductor 1 in Fig. 2 (clockwise direction). Then, at the position of the charging unit 4, the surface of the photoconductor 1 is uniformly charged (charging process). After that, the surface of the photoconductor 1 reaches the irradiation position of the laser light L emitted from the exposure unit 7 shown in Fig. 1, and an electrostatic latent image corresponding to each color is formed by exposure scanning at this position (exposure process).

[0019] Thereafter, the surface of the photoreceptor 1 reaches a position facing the developing unit 5, where the electrostatic latent image is developed to form a toner image of each color (developing process). Thereafter, the surface of the photoreceptor 1 faces a primary transfer roller 9 across the intermediate transfer belt 8 at a primary transfer unit, where the toner image on the photoreceptor 1 is transferred onto the intermediate transfer belt 8 (primary transfer process). The toner images of each color formed on the photoreceptor 1 of each color are transferred onto the intermediate transfer belt 8 in an overlapping manner, forming a color image on the intermediate transfer belt 8.

[0020] After passing through the primary transfer section, a small amount of untransferred toner remains on the surface of the photoreceptor 1. After that, the surface of the photoreceptor 1 reaches a position facing the cleaning section 2, and the untransferred toner remaining on the photoreceptor 1 is mechanically collected by the cleaning blade 2a (cleaning process). Finally, the surface of the photoreceptor 1 reaches a position facing the charge removing section, and the residual potential on the photoreceptor 1 is removed.

[0021] As shown in FIG. 1, the intermediate transfer unit 15 includes an intermediate transfer belt 8, four primary transfer rollers 9 (Y, M, C, K), a secondary transfer backup roller 12, a plurality of tension rollers, and an intermediate transfer cleaning unit. The intermediate transfer belt 8 is stretched and supported by a plurality of tension rollers, and moves endlessly in the direction of the arrow shown on the intermediate transfer belt 8 in FIG. 1 (counterclockwise direction) by the rotational drive of the secondary transfer backup roller 12, which is one of the roller members. The four primary transfer rollers 9 (Y, M, C, K) sandwich the intermediate transfer belt 8 between themselves and the photoconductors 1 (Y, M, C, K) to form primary transfer nips. A transfer bias opposite to the polarity of the toner is applied to the primary transfer rollers 9 (Y, M, C, K). The intermediate transfer belt 8 travels in the direction of the arrow shown on the intermediate transfer belt 8 in FIG. 1, and passes through the primary transfer nips of the respective primary transfer rollers 9 (Y, M, C, K) in sequence. In this way, the toner images of each color on the photoconductor 1 (Y, M, C, K) are superimposed on the intermediate transfer belt 8 and are primarily transferred.

[0022] The intermediate transfer belt 8, on which the toner images of each color are superimposed and primarily transferred, reaches a secondary transfer section facing a secondary transfer roller 19. In the secondary transfer section, a secondary transfer nip is formed by sandwiching the intermediate transfer belt 8 between a secondary transfer backup roller 12 and the secondary transfer roller 19. The four-color toner images formed on the intermediate transfer belt 8 are secondarily transferred onto a recording medium P, such as a transfer paper, transported to the position of the secondary transfer nip.

[0023] At this time, untransferred toner that has not been transferred to the recording medium P remains on the intermediate transfer belt 8. Thereafter, the intermediate transfer belt 8 reaches the position of an intermediate transfer cleaning unit, and the untransferred toner on the intermediate transfer belt 8 is collected. In this way, a series of transfer processes performed on the intermediate transfer belt 8 is completed.

[0024] The recording medium P transported to the position of the secondary transfer nip is transported from a paper feed section 26 provided below the image forming apparatus 100 via a paper feed roller 27, a pair of registration rollers 28, and the like. More specifically, a plurality of recording media P are stored in a stack in the paper feed section 26. When the paper feed roller 27 is driven to rotate counterclockwise in FIG. 1, the topmost recording medium P is fed toward between the rollers of the pair of registration rollers 28.

[0025] The recording medium P conveyed to the registration roller pair 28 is temporarily stopped at the roller nip of the registration roller pair 28, whose rotational drive has been stopped. Then, in synchronization with the color image on the intermediate transfer belt 8, the registration roller pair 28 is rotated and the recording medium P is conveyed toward the secondary transfer nip. In this way, the desired color image is transferred onto the recording medium P.

[0026] The recording medium P onto which the color image has been transferred at the secondary transfer nip is transported to the fixing unit 20. Then, at this position, the color image transferred onto the surface of the recording medium P is fixed onto the recording medium P by heat and pressure from a fixing belt and a pressure roller.

[0027] Thereafter, the recording medium P passes between the rollers of the discharge roller pair 29 and is discharged to the outside of the apparatus. The recording medium P discharged to the outside of the apparatus by the discharge roller pair 29 is sequentially stacked on the stack unit 30 as an output image. In this way, a series of image formation processes in the image forming apparatus 100 is completed.

[0028] Next, the configuration and operation of the developing unit 5 in the image forming unit 6 will be described in more detail.

[0029] 2, the developing unit 5 has a developing roller 51 facing the drum-shaped photoconductor 1, a doctor blade 52 facing the developing roller 51, and two conveying screws 55 provided in a first developer container 53 and a second developer container 54. It also has a toner concentration detection sensor 56 that detects the toner concentration in the developer in the first developer container 53.

[0030] The developing roller 51 is composed of a magnet fixed inside, a sleeve that rotates around the magnet, etc. The developer containers (53, 54) contain a two-component developer G consisting of a carrier and a toner. The second developer container 54 communicates with a toner drop transport path 64 through an opening formed above it.

[0031] The sleeve of the developing roller 51 is driven to rotate in the direction of the arrow (counterclockwise direction) shown on the developing roller 51 in Fig. 2. The developer G carried on the developing roller 51 by the magnetic field formed by the magnet moves on the developing roller 51 as the sleeve rotates.

[0032] The developer G in the developing unit 5 is adjusted so that the ratio of toner in the developer (toner concentration) falls within a predetermined range. In response to toner consumption in the developing unit 5, the toner contained in the toner container 32 shown in FIG. 1 is replenished into the second developer accommodating unit 54 via the toner replenishing unit 60 shown in FIG. 1.

[0033] The toner supplied to the second developer container 54 is circulated through the two developer containers (53, 54) while being mixed and stirred together with the developer G by the transport screw 55. The toner in the developer G is attracted to the carrier due to frictional charging with the carrier, and is carried on the developing roller 51 together with the carrier by the magnetic force formed on the developing roller 51. The developer G carried on the developing roller 51 is transported in the direction of the arrow shown on the developing roller 51 in FIG. 2, and reaches the position of the doctor blade 52.

[0034] Then, after the amount of developer G on the developing roller 51 is adjusted to an appropriate amount at this position, it is transported to a position facing the photoconductor 1 (developing area), where the toner is attracted to the latent image formed on the photoconductor 1 by the electric field formed in the developing area. Thereafter, the developer G remaining on the developing roller 51 reaches above the first developer container 53 as the sleeve rotates, and is separated from the developing roller 51 at this position.

[0035] 1, the toner container 32 is drawn in a circular shape for convenience of illustration, but the shape of the toner container 32 installed in the image forming apparatus 100 according to the present embodiment is not limited to this. For example, any shape or type of element such as a toner cartridge or a toner bottle can be used as the toner container 32, as will be described later.

[0036] As described above, the image forming apparatus 100 according to the first embodiment includes a toner remaining amount detection device 200 for detecting the amount of toner remaining in the toner container 32. The toner remaining amount detection device 200 according to the first embodiment has a tuning fork 210 that is installed so as to receive the load from the toner container 32, and estimates the amount of toner remaining based on the vibration frequency at which the tuning fork resonates with the toner container 32. In the following description, the vibration frequency of the tuning fork 210 thus generated may also be referred to as the "resonance frequency." The toner remaining amount detection device 200 may be implemented as a part of the toner supply unit 60 shown in FIG. 1, for example. In this case, the toner supply unit 60 controls the amount of toner supplied to the imaging unit 6 using information on the amount of toner remaining detected by the toner remaining amount detection device.

[0037] <Configuration of the toner remaining amount detection device> A toner remaining amount detecting device 200 according to the first embodiment will be described with reference to Figures 3 to 6. Figure 3 is a diagram showing a schematic configuration of the toner remaining amount detecting device 200 according to the first embodiment.

[0038] As shown in Fig. 3, in the image forming apparatus 100 according to the first embodiment, a toner cartridge 32A is used as a toner container in which the remaining toner amount is detected by the remaining toner amount detecting device 200. The toner cartridge 32A is used by being fixedly installed in, for example, a toner container storage unit 70 of the image forming apparatus 100. The shape of the toner cartridge 32A is, for example, as shown in Fig. 3, a box shape having a polygonal main surface and a side surface of a predetermined thickness in the depth direction of the page.

[0039] The toner remaining amount detecting device 200 includes a tuning fork 210 , a vibration detecting unit 220 , and a control unit 230 .

[0040] Tuning fork 210 is installed so as to receive the load from toner cartridge 32A. In a general sense, tuning fork 210 is a sounder that generates a sound of a certain frequency when struck, and is made by bending homogeneous steel into a U-shape with a handle attached to the center. Tuning fork 210 has a pair of vibrating arms 211, 212 arranged opposite each other, a curved portion 213 connecting vibrating arms 211, 212, and a base portion 214 connected to curved portion 213. The pair of vibrating arms 211, 212 and curved portion 213 form the above-mentioned U-shape. Base portion 214 corresponds to the above-mentioned handle.

[0041] The pair of vibration arms 211, 212 are disposed below the bottom surface 32A1 of the bottommost part of the toner cartridge 32A so as to face the bottom surface 32A1, and are disposed so as to extend, for example, in the horizontal direction. One of the pair of vibration arms 211, 212 is disposed closer to the bottom surface 32A1, and the other vibration arm 212 is disposed below the one vibration arm 212. Therefore, in this embodiment, the tuning fork 210 is disposed so that the U-shape is rotated about 90 degrees and the straight portion extends in the horizontal direction. The base 214 is connected and fixed to a fixing member 216 such as the housing of the image forming apparatus 100.

[0042] Furthermore, a load transmission member 215 is provided on the upper surface of one of the vibrating arms 211 arranged on the upper side. The load transmission member 215 extends from the upper surface of the vibrating arm 211 toward the bottom surface 32A1 of the upper toner cartridge 32A, and is arranged so that its upper end comes into contact with the bottom surface 32A1. With this configuration, the tuning fork 210 is arranged to receive the load from the toner cartridge 32A. As a result, the tuning fork 210 resonates with the toner cartridge 32A and vibrates at a vibration frequency (resonant frequency) corresponding to this resonance.

[0043] The vibration detection unit 220 detects the vibration of the tuning fork 210 caused by the load received from the toner cartridge 32A. The vibration detection unit 220 is electrically connected to an input side piezoelectric transducer 221 installed on one vibrating arm 211 of the tuning fork 210 and an output side piezoelectric transducer 222 installed on the other vibrating arm 212. The vibration detection unit 220 is, for example, an oscillation circuit with the tuning fork 210 as a feedback circuit, and can detect information regarding the transition of the vibration of the tuning fork 210 based on the transition of the oscillation of this oscillation circuit when a load due to the mass of toner is applied to the load transmission member 215 from the toner cartridge 32A.

[0044] Based on information about the vibration of tuning fork 210 detected by vibration detection unit 220, control unit 230 estimates the amount of toner remaining in toner cartridge 32A.

[0045] FIG. 4 is a diagram showing the hardware configuration of the control unit 230 in FIG.

[0046] The control unit 230 includes a central processing unit (CPU) 231, a read only memory (ROM) 232, and a random access memory (RAM) 233. Each of these is electrically connected to each other via a system bus (not shown).

[0047] The CPU 231 is a processor that controls the entire toner remaining amount detection device 200 and comprehensively controls access to various devices connected to the system bus based on a control program stored in the ROM 232. The CPU 231 can realize various functions described later by executing the control program stored in the ROM 232 using the RAM 233 as a working area.

[0048] The ROM 232 is a read-only non-volatile memory, and stores control programs, control data, and the like used by the CPU 231. The ROM 232 also stores information related to the toner remaining amount detecting device 200 that is used by the control programs.

[0049] The RAM 233 is a volatile memory that allows high speed reading and writing of information, and is used as a work frame memory for expanding recorded data and storing environmental data.

[0050] The CPU 221 can exchange data with an operation panel 251 provided in the image forming apparatus 100. The operation panel 251 has a display unit that displays information and an input unit that accepts operations, and functions as a user interface. The CPU 221 causes the operation panel 271 to display information on the remaining amount of toner estimated based on the vibration frequency detected by the vibration detection unit 220, and also causes the operation panel 271 to display instructions for ordering or replacing toner under predetermined conditions.

[0051] A power supply 252 is an AC commercial power supply, and a power supply circuit 253 converts an AC voltage supplied from the power supply 252 into a DC voltage and supplies power to each unit of the image forming apparatus 100. A CPU 221 can control the power supply from the power supply circuit 253 to each unit of the image forming apparatus 100.

[0052] Furthermore, the CPU 221 can exchange signals and data with the vibration detection unit 220 and control the operation of the imaging unit 6 .

[0053] Various functions implemented by the CPU 221, which will be described later, may be implemented by an electronic circuit or an electric circuit, such as an application specific integrated circuit (ASIC) or a field-programmable gate array (FPGA).

[0054] FIG. 5 is a functional block diagram of the control unit 230 according to the first embodiment.

[0055] As shown in FIG. 5, the control unit 230 includes a remaining toner amount estimating unit 241, an output unit 242, a first remaining toner amount detecting unit 243, a pixel counting unit 244, and a second remaining toner amount detecting unit 245.

[0056] Of these, the functions of remaining toner amount estimating section 241, output section 242, first remaining toner amount detecting section 243, pixel counting section 244 and second remaining toner amount detecting section 245 are realized by CPU 231 executing a predetermined program or the like.

[0057] The remaining toner amount estimating section 241 estimates the remaining amount of toner in the toner cartridge 32A, and outputs the estimation result to the notification section 250 of the operation panel 271 via the output section 242.

[0058] First remaining toner amount detection unit 243 detects the remaining toner amount based on the resonance frequency detection value input at a predetermined sampling period from vibration detection unit 220. Then, first remaining toner amount information indicating the detection value of the remaining toner amount is output to remaining toner amount estimation unit 241 and second remaining toner amount detection unit 265.

[0059] When the image forming apparatus 100 executes image formation, the pixel counting unit 244 counts the number of pixels constituting the image formed on the recording medium P. This pixel counting is performed every time an image is formed on the recording medium P, and a cumulative pixel count number is obtained. This cumulative pixel count number corresponds to the "cumulative value of the number of pixels" and is an example of "cumulative information".

[0060] Here, pixel counting unit 244 can reset the cumulative pixel count number at a predetermined opportunity. The "predetermined opportunity" includes, for example, a time when the ambient temperature of the toner cartridge changes from within a predetermined temperature range to outside the predetermined range. This reset process of the inferred pixel count number is performed, for example, by a control command from remaining toner amount estimating unit 241. When the cumulative pixel count number is reset, pixel counting unit 244 starts counting from the initial state of 0. Pixel counting unit 244 outputs the cumulative pixel count number to second remaining toner amount detecting unit 245 every time image formation is performed.

[0061] The second remaining toner detection unit 245 predicts the amount of toner consumption based on the cumulative pixel count number input from the pixel count unit 244. Then, the remaining toner amount is detected by subtracting the amount of toner consumption from a reference value of the remaining toner amount in the toner cartridge 32A (toner container 32).

[0062] Here, when the toner cartridge 32A is in a full state, the remaining toner amount when the toner cartridge is initially full is set as the reference value of the remaining toner amount. Also, when the first remaining toner amount detection unit 243 detects the remaining toner amount, the remaining toner amount indicated by the first remaining toner amount information is set as the reference value of the remaining toner amount.

[0063] After detecting the remaining toner amount by the cumulative information method, second remaining toner amount detection unit 245 outputs second remaining toner amount information indicating the detected value of the remaining toner amount to remaining toner amount estimation unit 241.

[0064] FIG. 6 is a flowchart of remaining toner amount detection control according to the first embodiment.

[0065] In step S101, the image forming apparatus 100 is powered on or returns from a sleep state.

[0066] In step S102, it is confirmed whether or not an initial operation has been performed on the image forming apparatus 100. The initial operation is performed, for example, when the power is turned on, and includes a preparatory operation for making each element of the image forming apparatus 100 in a stopped state ready to execute a print job.

[0067] If the initial operation has been performed (Yes in S102), the process proceeds to step S103, where the first remaining toner detection unit 243 acquires information on the resonance frequency of the tuning fork 210 from the vibration detection unit 220 (detection step, acquisition step). This frequency is stored as the "first vibration frequency f1 at which the tuning fork 210 resonates with the toner cartridge 32A before the print job starts." Note that in FIG. 6, this "first vibration frequency f1" is written as "resonance frequency f1."

[0068] On the other hand, if the initial operation has not been performed (No in S102), the process proceeds to step S104, where the resonance frequency finally acquired as the first vibration frequency f1 in the previous processing flow (last-time finally acquired resonance frequency) is reflected as the first vibration frequency f1 (detection step, acquisition step). In other words, the "first vibration frequency f1" is overwritten and saved with new information only when the initial operation is performed in the image forming apparatus 100.

[0069] After step S103 or S104, the image forming apparatus 100 goes into a standby state before executing a print job in step S105. After that, the image forming apparatus 100 goes into a state in which it can start a print job at any timing.

[0070] In step S106, the process waits until a print job is started by image forming apparatus 100, and after the print job is started, the process proceeds to step S107.

[0071] In step S107, the image forming apparatus 100 performs a printing operation.

[0072] In step S108, the process waits until the print job is completed by image forming apparatus 100, and after the print job is completed, the process proceeds to step S109.

[0073] In step S109, first toner remaining amount detection unit 243 acquires information on the resonance frequency of tuning fork 210 from vibration detection unit 220 (detection step, acquisition step). This frequency is stored as "second vibration frequency f2 at which the tuning fork resonates with toner cartridge 32A after the print job is completed." In other words, "second vibration frequency f2" is overwritten and saved with new information every time a print job is performed in image forming apparatus 100. Note that in FIG. 6, this "second vibration frequency f2" is written as "resonance frequency f2."

[0074] In step S110, image forming apparatus 100 goes into a standby state after the print job is completed.

[0075] In step S111, the pixel counting unit 244 counts the number of pixels constituting the image formed on the recording medium P in the current print job. The pixel counting unit 244 outputs information on the number of pixels counted in the current print job (pixel count value) to the second toner remaining amount detection unit 245.

[0076] In step S112, the remaining toner amount estimating unit 241 calculates and notifies the remaining toner amount W (estimation step). For example, the estimation process in this step is performed in the following steps (1) to (3).

[0077] (1) The first toner remaining amount detection unit 243 calculates a first estimated value W1 of the toner usage amount of the current print job by using the difference between the first vibration frequency f1 before the start of the print job acquired in step S103 or S104 and the second vibration frequency f2 after the end of the print job acquired in step S109. It is known that the tuning fork 210 has a characteristic that the oscillation frequency changes when weight is applied. Focusing on this characteristic, the first toner remaining amount detection unit 243 estimates the toner weight value based on the change amount of the resonance frequencies f1 and f2 before and after the print job by using a load detection device based on a tuning fork structure, that is, the tuning fork 210 and the vibration detection unit 220 included in the toner remaining amount detection device 200 of this embodiment. The first toner remaining amount detection unit 243 has, for example, a frequency / weight value conversion table in which the relationship between the difference between the resonance frequencies f1 and f2 before and after the print job and the weight is tabulated in advance in a memory or the like. The first toner remaining amount detection unit 243 calculates the difference between the resonance frequency f1 before the start of the print job obtained in step S103 or S104 and the resonance frequency f2 after the print job is completed obtained in step S109. Then, by referring to a frequency / weight value conversion table, the first toner remaining amount detection unit 243 obtains a toner weight value corresponding to the difference between the resonance frequency f1 and the resonance frequency f2. The first toner remaining amount detection unit 243 outputs the toner weight value obtained in this manner to the toner remaining amount estimation unit 241 as a first estimated value W1.

[0078] (2) The second toner remaining amount detection unit 245 calculates a second estimated value W2 of the amount of toner used in the current print job using the information of the pixel count value acquired in step S111. The second toner remaining amount detection unit 245 has, for example, a table of toner weight values ​​(one-pixel weight values) that adhere to one pixel due to environmental changes stored in a memory or the like in advance. The second toner remaining amount detection unit 245 acquires a one-pixel weight value from this table based on the environmental conditions at the time of execution of the current print job. The value obtained by multiplying the one-pixel weight value by the pixel count value becomes the toner weight value used obtained from the acquired pixel count value. The second toner remaining amount detection unit 245 outputs the toner weight value acquired in this way to the toner remaining amount estimation unit 241 as the second estimated value W2.

[0079] (3) The remaining toner amount estimating unit 241 estimates the remaining toner amount W using the first estimated value W1 and the second estimated value W2. For example, the remaining toner amount estimating unit 241 averages the first estimated value W1 and the second estimated value W2 to calculate the toner weight value used in the current print job. The initial value of the toner weight value contained in the toner cartridge 32A is uniformly determined depending on the type of the toner cartridge 32A used in the image forming apparatus 100. After the start of use of the toner cartridge 32A to be estimated, the remaining toner amount estimating unit 241 repeats a process of subtracting the toner weight value calculated for each print job from this initial value, and holds it as the latest toner weight value, i.e., the remaining toner amount. In other words, the remaining toner amount estimating unit 241 subtracts the toner weight value calculated in the current processing flow from the remaining toner amount calculated in the previous processing flow to calculate the latest remaining toner amount W.

[0080] Furthermore, in step S112, the toner remaining amount estimation unit 241 outputs information on the toner remaining amount W estimated by the above steps (1) to (3) to the notification unit 250 of the operation panel 271 via the output unit 242, thereby notifying the user of the image forming apparatus 100 of the toner remaining amount.

[0081] In step S112, the remaining toner amount W may be estimated using only the difference between the first vibration frequency f1 before the start of the print job and the second vibration frequency f2 after the print job is completed. In this case, in the above step (3), the remaining toner amount W is calculated by repeating the process of subtracting only the first estimated value W1 calculated in step (1) from the initial value of the toner weight for each print job.

[0082] The image forming apparatus 100 according to the first embodiment includes a toner cartridge 32A as an example of a toner container 32 that contains toner, an image forming unit 6 to which the toner contained in the toner cartridge 32A is supplied to form a toner image, and a toner remaining amount detection device 200 that detects the remaining amount W of toner in the toner cartridge 32A. The toner remaining amount detection device 200 includes a tuning fork 210 that is installed to receive a load from the toner cartridge 32A, a vibration detection unit 220 that detects the vibration of the tuning fork 210 due to the load, and a control unit 230 that estimates the remaining amount W of toner based on the vibration. The control unit 230 acquires a first vibration frequency f1 that resonates with the toner cartridge 32A before the start of a print job and a second vibration frequency f2 that resonates with the toner cartridge 32A after the end of the print job, and estimates the remaining amount W of toner using the difference between the first vibration frequency f1 and the second vibration frequency f2.

[0083] With this configuration, the remaining toner amount W can be estimated using information that is not easily affected by the uneven distribution of toner in the toner cartridge 32A (toner container 32), such as the resonance frequencies f1 and f2 at which the tuning fork 210 resonates with the toner cartridge 32A. This allows the image forming apparatus 100 to accurately detect the remaining toner amount W, regardless of the remaining amount in the toner container 32 or the uneven distribution of toner.

[0084] Furthermore, in the image forming apparatus 100 according to the first embodiment, the control unit 230 calculates a first estimated value W1 of the amount of toner used in the print job using the difference between the first vibration frequency f1 and the second vibration frequency f2, calculates a second estimated value W2 of the amount of toner used in the print job using the pixel count number in the print job, and estimates the remaining toner amount W using the first estimated value W1 and the second estimated value W2.

[0085] With this configuration, the remaining toner amount W is estimated using not only the resonant frequencies f1 and f2 but also information on the pixel count number for each print job, making it possible to make an estimation that is less affected by the remaining amount in the toner cartridge 32A (toner container 32) or toner imbalance, and thereby making it possible to detect the remaining toner amount W even more accurately.

[0086] Moreover, in the image forming apparatus 100 according to the first embodiment, a toner cartridge 32A is used as the toner container 32. The toner cartridge 32A is generally rectangular as shown in FIG. 3, and in many cases, the bottom surface portion is flat. This makes it easy to install the tuning fork 210 of the toner remaining amount detection device 200 so that it can come into contact with the bottom portion of the toner cartridge 32A. Therefore, the toner remaining amount detection device 200 according to the first embodiment is capable of detecting the amount of toner remaining with a simple configuration.

[0087] <Modification of remaining toner amount detection control> A modified example of the toner remaining amount detection control will be described with reference to Fig. 7. Fig. 7 is a flowchart of the modified example of the toner remaining amount detection control. As shown in the flowchart of Fig. 7, the remaining toner amount W may be estimated by selecting one of two estimation methods, namely, a process for estimating the remaining toner amount by first remaining toner amount detection unit 243 and a process for estimating the remaining toner amount by second remaining toner amount detection unit 245, based on a predetermined condition.

[0088] 7, the "predetermined condition" is the remaining toner amount W. When the remaining toner amount W is equal to or less than the predetermined threshold value TH, the process of estimating the remaining toner amount by the first remaining toner amount detection unit 243 is selected. On the other hand, when the remaining toner amount W is greater than the predetermined threshold value TH, the process of estimating the remaining toner amount by the second remaining toner amount detection unit 245 is selected.

[0089] In step S201, the image forming apparatus 100 is powered on or returns from a sleep state.

[0090] In step S202, the toner remaining amount estimation unit 241 determines whether the current remaining amount of toner in the toner cartridge 32A is equal to or less than a predetermined threshold value TH. The toner remaining amount estimation unit 241 stores the remaining amount of toner W finally calculated in the previous processing flow in a memory or the like, and compares this stored information with the threshold value to make the determination.

[0091] If the remaining toner amount is equal to or less than the threshold value TH (Yes in step S202), the process proceeds to step S203, where the first remaining toner amount detection unit 243 acquires information on the first vibration frequency f1 before the start of the print job from the vibration detection unit 220. In addition, in FIG. 7, this "first vibration frequency f1" is expressed as "resonance frequency f1."

[0092] On the other hand, if the remaining toner amount is greater than the threshold value TH (No in step S202), the process proceeds to step S204, where second remaining toner amount detection unit 245 detects the remaining toner amount based on the pixel count number acquired by pixel count unit 244.

[0093] After step S203 or S204, the process waits in step S205 until a print job is started by the image forming apparatus 100, and after the print job is started, the process proceeds to step S206.

[0094] In step S206, the image forming apparatus 100 performs a printing operation.

[0095] In step S207, the process waits until the print job is completed by the image forming apparatus 100, and after the print job is completed, the process proceeds to step S208.

[0096] In step S208, the remaining toner amount estimation unit 241 determines whether the current remaining toner amount in the toner cartridge 32A is equal to or less than a predetermined threshold value TH. The remaining toner amount information used in this step is the remaining toner amount W finally calculated in the previous processing flow, as in step S202.

[0097] If the remaining toner amount is equal to or less than the threshold value TH (Yes in step S208), the process proceeds to step S209, where the first remaining toner amount detection unit 243 acquires information on the second vibration frequency f2 after the start of the print job from the vibration detection unit 220. In addition, in FIG. 7, this "second vibration frequency f2" is represented as "resonance frequency f2."

[0098] On the other hand, if the remaining toner amount is greater than the threshold value TH (No in step S208), the process proceeds to step S210, where second remaining toner amount detection unit 245 detects the remaining toner amount based on the pixel count number acquired by pixel count unit 244.

[0099] In step S211, remaining toner amount estimating unit 241 calculates and notifies remaining toner amount W. For example, the estimation process in this step is performed by selecting one of the following two methods.

[0100] In the first estimation process, when the resonance frequencies f1 and f2 before and after the print job are acquired in steps S203 and S209, the first remaining toner amount detection unit 243 calculates a first estimated value W1 of the toner weight value used in the current print job, similar to procedure (1) of step S112 in Fig. 7. Then, the latest remaining toner amount W is calculated by subtracting the first estimated value W1 from the previous value of the remaining toner amount finally calculated in the previous processing flow.

[0101] In the second estimation process, when remaining toner amount detection by pixel counting is performed in steps S204 and S210, second remaining toner amount detection unit 245 calculates a second estimated value W2 of the toner weight value used in the current print job, similar to procedure (2) of step S112 in Fig. 7. Then, the latest remaining toner amount W is calculated by subtracting second estimated value W2 from the previous value of the remaining toner amount finally calculated in the previous processing flow.

[0102] Also, in step S211, the toner remaining amount estimation unit 241 outputs information on the toner remaining amount W estimated by the above-mentioned first estimation process or second estimation process to the notification unit 250 of the operation panel 271 via the output unit 242, thereby notifying the user of the image forming device 100 of the toner remaining amount.

[0103] In other words, in the processing of the modified example shown in the flowchart of Figure 8, when the amount of toner remaining in toner cartridge 32A is greater than a threshold value, toner remaining amount estimation unit 241 selects the second estimation process by second toner remaining amount detection unit 245 to estimate the amount of toner remaining, and when the amount of toner remaining in toner cartridge 32A is equal to or less than the threshold value, switches to the first estimation process by first toner remaining amount detection unit 243 to estimate the amount of toner remaining.

[0104] As shown in FIG. 7, the control unit 230 may be configured to switch the process of estimating the remaining toner amount W so that when the remaining toner amount is equal to or less than a predetermined threshold value TH, a process of estimating the remaining toner amount W is performed using the difference between the first vibration frequency f1 and the second vibration frequency f2, and when the remaining toner amount is greater than the threshold value TH, a process of estimating the remaining toner amount W is performed using the pixel count number in the print job.

[0105] When the amount of toner remaining in the toner cartridge 32A (toner container 32) becomes small, the container is filled with substances other than toner, such as air, and this tends to cause the toner in the container to become unevenly distributed. When there is uneven distribution of toner, it is considered that the conventional method for estimating the amount of remaining toner may be affected by a decrease in the accuracy of estimation. In this modified example, the above-mentioned configuration allows the first remaining toner detector 243, which is less susceptible to such influences, to estimate the amount of remaining toner W based on the resonance frequencies f1 and f2 of the tuning fork 210 when the amount of remaining toner becomes small and uneven distribution of toner is likely to occur. This allows the image forming apparatus 100 to accurately detect the amount of remaining toner W, regardless of the amount of remaining toner in the toner container 32 or the uneven distribution of toner.

[0106] [Second embodiment] The second embodiment will be described with reference to Fig. 8. Fig. 8 is a diagram showing a schematic configuration of a toner remaining amount detecting device 200A according to the second embodiment. Fig. 8 is an exploded perspective view showing the components relating to the toner remaining amount detecting device 200A.

[0107] In the toner remaining amount detecting device 200A, a toner bottle 32B is used as the toner container 32. The toner bottle 32B includes a cylindrical, hollow toner body 32B1 and an outlet 32B2 provided at one end of the toner body 32B1 in the axial direction. The outlet 32B2 is cylindrical with a smaller diameter than the toner body 32B1 and is provided to protrude in the axial direction from one end of the toner body 32B1 so as to be coaxial with the toner body 32B1.

[0108] A groove 32B3 for conveying the toner is formed inside the toner body 32B1. When the toner body 32B1 rotates around the axis of the cylindrical shape while the toner is accommodated inside, the toner is conveyed along the groove 32B3 to the discharge port 32B2 side.

[0109] A cover 33 is attached around the outer periphery of the end of the toner body 32B1 on the discharge port 32B2 side to cover the discharge port 32B2. A gear 32B4 is provided around the entire circumference of the cylindrical outer periphery of the discharge port 32B2. A gear system 34 is inserted into this gear 32B4 from the outside of the cover 33, and one gear in the gear system 34 that is closest to the gear 32B4 meshes with the gear 32B4. In addition, a gear located at the end opposite to the gear meshing with the gear 32B4 in the gear system 34 is attached to the drive shaft of the motor 35.

[0110] Therefore, when the motor 35 is driven, the rotational driving force is transmitted to the toner bottle 32B via the gear system 34, causing the toner bottle 32B to rotate. As a result, the toner contained inside the toner bottle 32B is discharged along the groove 32B3 to the discharge port 32B2.

[0111] Particularly in the toner remaining amount detecting device 200A of the second embodiment, the tuning fork 210A is connected to the lower part of the motor 35. This makes it possible to use the vibrations generated by driving the motor 35 as energy for vibrating the tuning fork 210A.

[0112] In the second embodiment, tuning fork 210 is configured to also receive the load of toner bottle 32B, which is connected to motor 35 via gear system 34, etc., so tuning fork 210A is installed so as to indirectly receive the load from toner bottle 32B as well.

[0113] As in the first embodiment, a vibration detection unit 220 is connected to tuning fork 210, and a control unit 230 is connected to vibration detection unit 220. The configuration in which vibration detection unit 220 detects the vibration of tuning fork 210A and the configuration in which control unit 230 estimates the remaining toner amount based on the vibration are the same as in the first embodiment. In other words, the functional blocks of control unit 230 in the second embodiment are the same as those in the first embodiment shown in Figure 5, and the remaining toner amount detection control in the second embodiment is the same as the processing in the flowcharts of the first embodiment shown in Figures 6 and 7.

[0114] It is not necessary to keep the motor 35 rotating during the process of estimating the remaining toner amount. It is sufficient to rotate the motor 35 for a moment and measure the amount of remaining toner while it is vibrating.

[0115] Furthermore, in the configuration of the second embodiment, tuning fork 210A is subjected to the loads of elements other than the measurement target, such as motor 35 and gear system 34, in addition to toner bottle 32B. For this reason, it is considered that the vibration generated by the tuning fork is affected not only by the increase or decrease in the toner inside toner bottle 32B, but also by the loads of motor 35, gear system 34, toner bottle 32B, etc. Regarding this effect, for example, by measuring the difference in weight between motor 35, gear system 34, and toner bottle 32B each time toner is discharged, data that can be used to correct the resonance frequency of tuning fork 210 can be obtained.

[0116] A clutch may be provided in gear system 34 to interrupt the power transmission between motor 35 and toner bottle 32B when detecting the vibration of tuning fork 210. This makes it possible to suppress disturbance in the vibration of tuning fork 210A caused by the rotation of toner bottle 32B moving the toner inside toward outlet 32B2, thereby improving the accuracy of vibration detection.

[0117] Also, a support portion or the like may be used on cover 33 to apply a load to tuning fork 210A.

[0118] Also, a large balance may be prepared on which all of the elements related to toner bottle 32B shown in Fig. 8 or the entire mechanism including other elements related to toner bottle 32B not shown in Fig. 8 can be placed. In this case, the mechanism to be measured is placed on one side of the balance, and the other side of the balance is pressed against tuning fork 210A. The size of the balance can be varied depending on the assembly precision, cost, and area.

[0119] In the image forming apparatus 100 according to the second embodiment, the toner container 32 is a toner bottle 32B. The image forming apparatus includes a motor 35 that rotates the toner bottle 32B to supply the toner in the toner bottle 32B to the imaging unit 6. The tuning fork 210A of the toner remaining amount detection device 200A is installed so as to receive the load generated by driving the motor 35.

[0120] In a configuration in which the toner bottle 32B is used as the toner container 32, it is necessary to rotate the toner bottle 32B to discharge the toner, so it is difficult to directly measure the change in load associated with the change in the amount of toner remaining inside the toner bottle 32B. On the other hand, the motor 35, which is the drive source for rotating the toner bottle 32B, is generally fixed to a fixed element in the image forming apparatus, so it is easy to arrange the tuning fork 210A in contact with the motor 32B so that it receives the load, as in the toner cartridge 32A of the first embodiment. In addition, when the amount of toner remaining in the toner bottle 32B changes, the weight of the entire toner bottle 32B also changes, so the driving force generated by the motor 35 when the toner bottle 32B is rotated at a constant speed also changes. In other words, the vibration generated by the driving of the motor 35 also changes according to the change in the amount of toner remaining. Therefore, in the second embodiment, with the above configuration, tuning fork 210A is positioned to receive the load of motor 35, so that changes in vibration accompanying changes in the amount of toner remaining in toner bottle 32B (toner container 32) can be indirectly detected, and the amount of toner remaining W can be accurately detected regardless of the amount remaining in toner container 32 or the uneven distribution of toner.

[0121] In the image forming apparatus 100 according to the second embodiment, the motor 35 is preferably designed so that the vibration frequency generated during operation includes the design median value of the resonance frequency of the tuning fork 210A and its neighboring frequencies. This configuration makes it possible to amplify the vibration frequency generated by the tuning fork 210A resonating with the motor 35, and by using the amplified vibration frequency, the remaining toner amount can be estimated with higher accuracy.

[0122] In addition, even in a configuration in which a toner bottle 32B is applied to an image forming apparatus 100 as a toner container 32, such as the toner remaining amount detection device 200A of the second embodiment, the tuning fork 210A may be configured to receive a load directly from the toner bottle 32B via a load transmission member 215 as shown in Figure 3, as in the first embodiment.

[0123] [Third embodiment] The third embodiment will be described with reference to Figures 9 and 10. Figure 9 is a plan view showing a schematic configuration of a toner remaining amount detecting device 200B according to the third embodiment. Figure 10 is a side view showing a schematic configuration of a toner remaining amount detecting device 200B according to the third embodiment.

[0124] 9 and 10 show three axes, the X-axis, the Y-axis, and the Z-axis. The extension direction of the X-axis (X direction), the extension direction of the Y-axis (Y direction), and the extension direction of the Z-axis (Z direction) are perpendicular to each other. The X-direction is the axial direction of the toner bottle 32B and the direction in which it is inserted into and removed from the toner container mount 70. The Y-direction is the arrangement direction of the multiple tuning forks 210B, terminals 261, and electrodes 32B6. The Z-direction is the stacking direction of the elements of the toner remaining amount detection device 200B, such as the tuning fork 210, the terminals 261, and the electrodes 32B6.

[0125] 9 and 10, in the image forming apparatus 100 according to the third embodiment, a toner bottle 32B as an example of a toner container 32 is configured to be inserted and installed in the toner container storage unit 70 by moving the toner bottle 32B from the negative X direction side to the positive X direction side. The toner bottle 32B is configured to be pulled out and removed from the toner container storage unit 70 by moving the toner bottle 32B in the negative X direction side.

[0126] The toner bottle 32B is provided with an ID board 32B5. Information specific to the toner bottle 32B (e.g., model number, manufacturer, date of manufacture, etc.) is recorded on the ID board 32B5. An electrode 32B6 is electrically connected to the ID board 32B5. The electrode 32B6 is disposed on the surface of the toner bottle 32B and is installed so as to be exposed to the outside. In this embodiment, the electrode 32B6 is installed so as to face downwards of the toner bottle 32B when the toner bottle 32B is accommodated in the toner container accommodation unit 70.

[0127] Image forming apparatus 100 includes a communication circuit 260 and a terminal 261. Communication circuit 260 communicates information with toner bottle 32B. For example, communication circuit 260 acquires the above-mentioned unique information from ID board 32B5 on the toner bottle 32B side. Terminal 261 is connected to communication circuit 260, and electrically connects ID board 32B5 of toner bottle 32B to communication circuit 260 by contacting electrode 32B6 on the toner bottle 32B side.

[0128] 10, the electrode 32B6 is disposed at a position where it comes into contact with the electrode 32B6 on the toner bottle 32B side when the toner bottle 32B is placed at a predetermined position in the toner container mount 70. Also, as shown in Fig. 9, in this embodiment, four terminals 261 and four electrodes 32B6 are provided, and they are all arranged in the Y direction so that each terminal 261 comes into contact with one of the four electrodes 32B6.

[0129] Further, the toner container holder 70 of the image forming apparatus 100 is provided with a guide member 262. The guide member 262 has a pair of members arranged on the outer sides of the positive and negative Y direction sides of the four terminals 261, as shown in Fig. 9 for example. By providing the pair of guide members 262 in this manner, the position of the electrode 32B6 in the Y direction can be aligned with the position of the terminal 261 when the toner bottle 32B is inserted into the toner container holder 70.

[0130] 10, the guide member 262 is provided with an inclined surface along the insertion direction of the toner bottle 32B into the toner container holder 70. The inclined surface is formed so as to protrude in the Z positive direction as it advances toward the X positive direction. By providing the guide member 262 with an inclined surface in this manner, when the toner bottle 32B is inserted into the toner container holder 70, the position of the electrode 32B6 in the Z direction can be aligned to a position where it can come into contact with the terminal 261.

[0131] In particular, in this embodiment, the tuning fork 210B of the toner remaining amount detecting device 200B is made of metal, is formed integrally with the terminal 261, and is configured to receive the load of the toner bottle 32B via the terminal 261. Specifically, as shown in FIG. 9, the tuning fork 210B has a base 214 standing on the Z positive side from the communication circuit 260 and is electrically connected to the communication circuit 260. The terminal 261 is connected to one of the vibrating arms arranged on the Z positive side of the U-shaped portion connected to the base 214. As shown in FIG. 10, four tuning forks 210B are also provided and arranged along the Y direction, and each tuning fork 210B is connected to one of the four terminals 261. As a result, the four sets of terminals 261 and the tuning fork 210B are formed integrally. Then, by contacting the terminal 261 with the electrode 32B6, the ID board 32B5 on the toner bottle 32B side and the communication circuit 260 on the image forming apparatus side are electrically connected via the terminal 261 and the tuning fork 210B.

[0132] As in the first embodiment, a vibration detection unit 220 is connected to tuning fork 210B, and a control unit 230 is connected to vibration detection unit 220. The configuration in which vibration detection unit 220 detects the vibration of tuning fork 210B and the configuration in which control unit 230 estimates the remaining toner amount based on the vibration are the same as in the first embodiment. In other words, the functional blocks of control unit 230 in the third embodiment are the same as those in the first embodiment shown in Figure 5, and the remaining toner amount detection control in the third embodiment is the same as the processing in the flowcharts of the first embodiment shown in Figures 6 and 7.

[0133] In this way, in the third embodiment, the tuning fork 210B of the toner remaining amount detecting device 200B is formed integrally with the terminal 261 serving as an electrical connection element between the ID board 32B5 on the toner bottle 32B side and the communication circuit 260 on the image forming apparatus side. With this configuration, a single mechanism can be realized as both the positioning mechanism for applying the weight of the toner bottle 32B to the tuning fork 210B and the positioning mechanism for inserting and removing the toner bottle 32B into and from the toner container storage unit 70, making it possible to achieve both positioning functions with a simple configuration.

[0134] In the toner remaining amount detecting device 200B of the third embodiment, the toner bottle 32B is used as the toner container 32 in the example of FIGS. 9 and 10, but the toner cartridge 32A may be used instead.

[0135] The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Any design modifications made by a person skilled in the art to these specific examples are also included within the scope of the present disclosure as long as they have the features of the present disclosure. The elements of each of the above-mentioned specific examples and their arrangements, conditions, shapes, etc. are not limited to those exemplified and can be changed as appropriate. The combination of each of the elements of each of the above-mentioned specific examples can be changed as appropriate as long as no technical contradiction occurs. [Explanation of symbols]

[0136] 100 Image forming device 6 Imaging section 32 Toner container 200, 200A, 200B Toner remaining amount detector 210, 210A, 210B Tuning fork 220 Vibration detection unit 230 Control Unit 32A Toner Cartridge 32B Toner bottle 32B6 electrode 35 Motor 260 Communication Circuit 261 Terminal W Estimated remaining toner amount f1 First vibration frequency (resonance frequency) f2 Second vibration frequency (resonant frequency) W1 First estimate W2 Second estimate TH Threshold [Prior art documents] [Patent documents]

[0137] [Patent Document 1] Patent Publication No. 2021-096428

Claims

1. a toner container for storing toner; an image forming unit that forms a toner image by receiving the toner contained in the toner container; a toner remaining amount detection device for detecting the amount of toner remaining in the toner container; Equipped with The toner remaining amount detection device is a tuning fork disposed to receive a load from the toner container; a vibration detection unit that detects vibration of the tuning fork due to the load; a control unit that estimates the remaining amount of toner based on the vibration; having the control unit acquires a first vibration frequency that resonates with the toner container before a print job is started and a second vibration frequency that resonates with the toner container after a print job is completed; estimating the remaining amount of toner using a difference between the first vibration frequency and the second vibration frequency; Image forming device.

2. The control unit is calculating a first estimate of toner usage for the print job using a difference between the first vibration frequency and the second vibration frequency; calculating a second estimate of toner usage for the print job using the pixel count for the print job; estimating the remaining toner amount using the first estimated value and the second estimated value; The image forming apparatus according to claim 1 .

3. The control unit is When the remaining amount of toner is equal to or less than a predetermined threshold, a process of estimating the remaining amount of toner using a difference between the first vibration frequency and the second vibration frequency is performed; when the remaining toner amount is greater than the threshold value, switching the process of estimating the remaining toner amount to perform a process of estimating the remaining toner amount using a pixel count number in the print job; The image forming apparatus according to claim 1 .

4. The toner container is a toner cartridge. The image forming apparatus according to any one of claims 1 to 3.

5. the toner container is a toner bottle, a motor that rotates the toner bottle to supply the toner in the toner bottle to the image forming unit; The tuning fork is installed to receive a load generated by driving the motor. The image forming apparatus according to any one of claims 1 to 3.

6. The motor generates a vibration frequency during operation that includes a design median value of the resonance frequency of the tuning fork and a frequency close to the design median value. The image forming apparatus according to claim 5 .

7. The tuning fork is made of metal; a communication circuit for communicating information with the toner container; an electrode provided on a surface of the toner container; a terminal connected to the communication circuit and in contact with the electrode to electrically connect the toner container to the communication circuit; Equipped with the tuning fork is integrally formed with the terminal and receives the load of the toner container via the terminal; The image forming apparatus according to any one of claims 1 to 3.

8. A toner remaining amount detection device for use in an image forming apparatus including a toner container that contains toner and an image forming unit that forms a toner image by being supplied with the toner contained in the toner container, the toner remaining amount detection device detecting an amount of toner remaining in the toner container, a tuning fork disposed to receive a load from the toner container; a vibration detection unit that detects vibration of the tuning fork due to the load; a control unit that estimates the remaining amount of toner based on the vibration; having the control unit acquires a first vibration frequency that resonates with the toner container before a print job is started and a second vibration frequency that resonates with the toner container after a print job is completed; estimating the remaining amount of toner using a difference between the first vibration frequency and the second vibration frequency; Toner remaining amount detection device.

9. A toner remaining amount detection method for an image forming apparatus including a toner container that contains toner and an image forming unit that forms a toner image by being supplied with the toner contained in the toner container, the method comprising: a detection step of detecting vibration of a tuning fork installed to receive a load from the toner container; an acquisition step of acquiring a first vibration frequency resonating with the toner container before a print job is started in the detection step, and a second vibration frequency resonating with the toner container after a print job is completed; an estimation step of estimating the remaining amount of toner using a difference between the first vibration frequency and the second vibration frequency acquired in the acquisition step; A toner remaining amount detection method comprising:

Images