JP3990950B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus having a replacement part such as a consumable such as a toner cartridge or an apparatus that can be replaced at the end of its service life.
[0002]
[Prior art]
FIG. 2 is a schematic configuration diagram of an example of a tandem type image forming apparatus.
[0003]
The tandem type image forming apparatus includes a plurality of image forming units of black (Bk), yellow (Y), magenta (M), and cyan (C).
[0004]
In the image forming unit 18 is a photoconductor drum (image carrier) made of an organic photoconductor or an amorphous silicon photoconductor. The photoconductor drum 18 is rotated by a charging device 16 such as a charging roller with a predetermined polarity and potential. The uniform charging process is applied.
[0005]
The scanner unit 11 outputs a laser beam 13 modulated in accordance with an image signal of target image information from an image signal generation unit such as an image reading device (not shown), and is not shown via an optical lens system (not shown). An electrostatic latent image is formed on the surface of the photosensitive drum by scanning and exposing the photosensitive drum 18 with the deflection mirror.
[0006]
FIG. 3 is a configuration diagram of the scanner unit 11 of the image forming unit. The operation of the scanner unit will be described with reference to the drawings. 31 is a semiconductor laser, 32 is a collimator lens, 33 is a cylindrical lens, 34 is a polygon mirror, 35 is a scanner motor, 36 is a spherical lens, 37 is an Fθ lens, 38 is a deflection mirror, and 39 is a horizontal synchronization signal detector. . The semiconductor laser 31 emits light by the laser drive signal modulated based on the image signal, and the laser light is shaped into a beam shape by the collimator lens 32 and the cylindrical lens 33. The polygon mirror 34 is rotated by the scanner motor 35 that rotates regularly, and the laser beam reflected by the polygon mirror surface is scanned in a fan shape. Further, the laser beam is shaped by an optical lens group such as a spherical lens 36, an Fθ lens 37, and a deflection mirror 38, and scans the surface of the photosensitive drum at a constant speed. The horizontal synchronizing signal detector is generally composed of a photodiode and an amplifier, detects a laser beam to be scanned, and generates a synchronizing signal in the main scanning direction.
[0007]
Further, FIG. 2 will be described. A developing unit 14 stores a developer (toner) therein and generally has a toner transport mechanism for the purpose of charging and transporting the toner. The photosensitive drum 18 on which the electrostatic latent image is formed is visualized as an image by selectively adhering toner according to the electrostatic state of the surface by contacting or approaching the developing roller 17. Reference numeral 22 denotes a cassette for storing the transfer material 29. The transfer material fed from the cassette 22 by the paper feed roller is conveyed between the photosensitive drum 18 and the transfer air 19 in the image forming unit by a conveyance belt 20 that holds and conveys the transfer material. At this time, the toner image on the photosensitive drum 18 developed in the above development process is transferred to the transfer material 29 by the transfer device 19. By sequentially passing through the four-color image forming units, the four-color developers are transferred in multiples. Residual toner on the photosensitive drum 18 that has not been transferred in this transfer process is removed and collected by a cleaning device 15 such as a cleaning blade. Reference numeral 23 denotes a fixing device. The fixing device 23 is generally constituted by a plurality of opposed rollers, and has a heating unit such as a heater inside or outside the rollers. Further, the fixing device 23 is provided with a temperature detector in the vicinity of the roller and is controlled so as to reach a predetermined temperature by monitoring the temperature by a CPU or the like and controlling the heating amount of the heater. The transfer material 29 onto which the toner has been transferred in the above-described transfer process is heated and pressurized by the fixing device 23 and melted and fixed. Thereafter, the fixed transfer material 29 is transported through the paper discharge mechanism and discharged from the image forming apparatus to complete printing.
[0008]
In such an image forming apparatus, conventionally, the developing unit 14 for storing toner is a replacement unit that needs to be replaced when the toner is consumed. Such a replacement unit is replaced by a user by detecting the remaining amount of toner and notifying the user of the replacement time. It is more preferable for the remaining amount detection of the toner to notify the user before the toner runs out and printing cannot be performed, rather than notifying that the toner has run out, because the user can prepare the replacement unit. Furthermore, ideally, if the usage amount of consumables is always informed, the user can accurately grasp not only the replacement time but also the usage status of the consumables. This is information for judging whether the product is sufficiently new. In this way, it is desirable that the replacement unit can accurately grasp the usage state.
[0009]
However, the replacement unit such as a consumable has a unit configuration different from that of the main body of the image forming apparatus. For example, when the developing unit 14 used in another image forming apparatus is attached to another image forming apparatus, the developing unit 14 It is difficult to determine how much is used. Therefore, the status of the exchange unit can be obtained by reading the information in the non-volatile memory of the exchange unit even between different image forming apparatuses by installing the non-volatile memory in the exchange unit and accumulating the usage amount of the exchange unit in this nonvolatile memory. Can be grasped correctly and can be notified to the user accurately.
[0010]
In such a system, there is a technology realized by mounting a nonvolatile memory such as an EEPROM in the replacement unit and connecting the image forming apparatus body with a connector when the replacement unit is mounted. When a non-volatile memory is mounted on an exchange unit, a drawer connector with a fitting member that is easily inserted and removed at the time of attachment / detachment is often used instead of a general harness connector. The fitting portion is formed with a guide member that absorbs misalignment due to the tolerance between the replacement unit and the main unit when the replacement unit is attached / detached, and the cost is higher than that of a general harness connector.
[0011]
In addition, since the nonvolatile memory mounting system using this drawer connector is a contact type, contact failure may occur due to, for example, toner dust inside the main unit or dust entering from the outside. There is a limitation that the contact point needs to be constituted by a sliding contact that is self-cleaned at the time of insertion / extraction.
[0012]
From such a viewpoint, a memory system capable of non-contact communication has been devised in recent years. This system is composed of a transmission circuit and a reception circuit, and is generally a system that superimposes data on a carrier wave called a carrier from the transmission circuit and supplies power to the nonvolatile memory by the carrier and transmits / receives data. The transmission circuit is configured with an antenna, and the antenna is also configured on the nonvolatile memory side. Power is supplied to the memory unit by driving the transmission-side antenna of the main unit with the above-described carrier and electromagnetically inducing the antenna of the memory unit on the replacement unit facing the contactless side by electromagnetic waves. In this system, the problem with respect to the reliability of the connector contact, which is a drawback of the contact-type nonvolatile memory mounting system, is avoided.
[0013]
As described above, usability is improved by recording the remaining toner amount detection information in the nonvolatile memory mounted in the replacement unit.
[0014]
[Problems to be solved by the invention]
Conventionally, the detection control of the replacement unit for detecting the remaining amount of toner is performed by the software of the image forming apparatus main body. However, the software is also the same amount of remaining toner detection control is performed at any exchange unit for a fixed to the image forming apparatus.
[0015]
At this time, for example, even when there are replacement units having different toner characteristics, the same detection control is performed. However, it has been found that the actual toner in the color image forming apparatus has different characteristics depending on the color. For example, when the means for detecting the remaining amount of toner is an optical transmission detection method using LED light, the transmittance differs depending on the color. Therefore, the accuracy is deteriorated when the actual toner remaining amount is calculated. In many cases, the fluidity of the toner differs due to the difference in the toner color and the actual composition of the toner and the composition of the components. This also causes a difference in detection accuracy between the replacement units for the respective colors when the toner remaining amount is detected under the same detection conditions. Further, these toner properties such as permeability and fluidity become difficult because improvement is required to maintain the accuracy of the remaining amount detection even when the replacement unit is improved after the product release of the image forming apparatus. Yes.
[0016]
[Means for Solving the Problems]
In order to solve the above problems, an image forming apparatus according to the present invention includes a plurality of developing units having a non-volatile memory that stores developers of different colors and stores a plurality of parameters according to the characteristics of the developers of the different colors. A plurality of light-emitting elements, a plurality of exposure means for causing the light-emitting elements to emit light based on image signals, a plurality of image carriers that form an electrostatic latent image by light emitted from the light-emitting elements, A plurality of transfer means for transferring an image formed on the image carrier to a transfer material by attaching a developer to the electrostatic latent image by a developing device; and heating and transferring the image transferred on the transfer material; An image forming apparatus comprising: a fixing unit that pressurizes and fixes; a stirring unit that stirs the developer in the developing unit; and the developer in the developing unit passes through the developing unit while stirring the developer in the developing unit. Light A developer remaining amount detecting means for detecting a transmission time by an optical detection method and outputting a light detection signal corresponding to the remaining amount of the developer in the developer; And the plurality of parameters corresponding to the plurality of parameters for calculating the remaining amount of the developer according to the flowability or flowability and permeability of the developer of the different color. A photodetection signal output by the detection means, and a fluidity of the developer of the different color stored in the non-volatile memory of the developer, or a linear function based on a plurality of parameters corresponding to fluidity and permeability And calculating means for calculating the remaining amount of the developer in the developing device.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
A detailed embodiment of an image forming apparatus to which the present invention is applied will be described below. In the present embodiment, since there are a plurality of units having the same function, the instruction numbers are indicated by a, b, c, d. Since the printing operation of the image forming apparatus is the same as that of the conventional example, a detailed description is omitted.
[0020]
FIG. 4 shows the configuration of the image forming apparatus of the present embodiment. Reference numeral 14 denotes a developing device described in the conventional example, and constitutes one unit together with the developing roller 17. The developing device 14 is a replacement unit that is replaced when the internal toner is consumed. A memory unit 101 is attached to the upper front surface of this unit. The image forming apparatus main body includes a communication unit 103, and an antenna unit 102 is disposed at a position facing the memory unit 101.
[0021]
Next, referring to FIG. 10, reference numeral 200 denotes an operation panel of the image forming apparatus, 201 denotes a key switch on the operation panel, and 203 denotes a developing device replacement door that is opened when the developing device that is a replacement unit is replaced. When communicating with the memory unit 101, the state of the developing device replacement door 203 is monitored. When the door is open, a communication error may occur at the time of attachment / detachment so that communication is not executed. Is.
Details of the communication unit 103 of this embodiment will be described with reference to FIG.
[0022]
105 is a communication IC. Reference numerals 101a, 101b, 101c, and 101d denote memory units each incorporating a non-volatile memory attached to the developing device 14 that is an exchange unit. Reference numerals 102a, 102b, 102c, and 102d denote antenna units that perform transmission and reception, and are configured by inductors. Reference numerals 104a, 104b, 104c, and 104d denote amplifier circuits in the transmission circuit. 106 is an analog switch for switching the transmission signal, and 107 is an analog switch for switching the reception signal. Reference numeral 108 denotes a receiving circuit.
[0023]
The communication IC 105 has a function of communicating with the memory unit 101 based on information designated by a CPU or logic IC (not shown). The communication IC 105 generates a transmission signal by superimposing the address and data of the memory unit designated by the CPU or logic IC on a carrier wave for supplying power to the memory unit 101. The transmission signal is connected to the transmission circuit by an analog switch 106. The analog switch 106 is composed of an FET and uses a multiplexer-type general-purpose IC with a built-in decoder function.
[0024]
The transmission signal switched by the analog switch 106 is amplified to a transmission signal by the amplifier circuit 104. Here, the amplifier circuit 104 will be described with reference to FIG. The input signal is connected to the base of a transistor coupled with a capacitor and biased. This transistor is preferably for high frequency amplification with good frequency characteristics. The transistor drives the inductor connected to the collector by the input signal and amplifies the signal to a large amplitude. The amplified signal is output as an amplitude signal through a coupling capacitor in the output stage. Returning to FIG. The amplified transmission signal drives the antenna unit 102 formed of an inductor and generates electromagnetic waves, thereby supplying power to the memory unit 101 and transmitting superimposed data. The memory unit returns a reception signal based on the transmission data. The received signal is received by the antenna unit 102 and received by the receiving circuit via the analog switch 107. FIG. 6 shows an example of a receiving circuit. The level of the received signal is compared and detected by a comparator. As for the received signal, received data is taken out by the communication IC and can be read out by a CPU or logic IC (not shown). Such a system realizes a system that can read and write the nonvolatile memory of the exchange unit without contact.
[0025]
Next, the toner remaining amount detection of the developing device 14 will be described with reference to FIG. The developing device 14 is driven to rotate together with the developing roller 17 and the toner stirring plate 304 by a gear of the image forming apparatus main body. At this time, in the image forming apparatus main body, the LED 301 and the light receiving element 302 are arranged at positions facing the stirring portion of the toner container where the toner stirring plate 304 rotates. The developing unit 14 is provided with a window made of a transmissive resin (not shown) in front of the LED 301 and the light receiving element 302 so that light can be transmitted. The toner agitating plate 304 has a function of agitating the toner by moving the toner in the developing device 14 when being rotated at a constant period, and changing the light transmission time according to the remaining amount of toner. is there.
[0026]
The detection will be described with reference to FIG. In the toner remaining amount detection, light is transmitted or blocked in a cycle by the toner stirring plate. At this time, the transmitted light is detected as shown in FIG. By comparing this detection signal with a predetermined threshold value, it is possible to obtain a signal whose duty varies with the amount of toner.
[0027]
A method for detecting the remaining amount will be described with reference to FIG. A memory unit 101 mounted on the developing device 14 stores a toner remaining amount detection parameter. This parameter is read by the CPU 303 and used for sampling and remaining amount calculation. As shown in FIG. 1, when the light of the LED 301 is detected by the light receiving element 302 and the light is detected, a low level signal can be obtained. The CPU 303 samples the light detection signal and calculates the duty. Further, the remaining amount of toner in the developing device 14 is calculated from the duty. Details of the detection will be described with reference to FIG. Since the detection signal is inverted and captured at the input unit of the CPU 303, the signal shown in FIG. For example, if time detection of the signal output compared with the threshold value in FIG. 11 is performed, the remaining amount of toner can be detected by the change in the transmission time. In this embodiment, a method is employed in which the transmission time during one rotation period is measured and the remaining amount is calculated from the duty.
[0028]
Next, the remaining amount detection will be described with reference to FIG. The developing device 14 has toners having different characteristics, and the transmission time is different even when the same number of printed sheets is used as shown in FIG. For example, with standard toner, the duty of transmission time at the time of printing 4000 sheets is about 40%. However, at this time, in the developing device 14 in which the toner having high fluidity is stored, the duty of the transmission time is 50%. Further, in the developing device 14 in which toner having the same fluidity but high permeability is stored, the transmission time duty is 60% or more.
[0029]
At this time, if the remaining amount calculation with respect to the transmission time is uniformly performed using the same table, a detection error occurs due to the difference in the toner characteristics. In order to avoid this, it is necessary to have a method for distinguishing the developing device 14 separately. Even when the memory unit 101 is mounted on the developing device 14, it often has determination information for distinguishing toner characteristics. In this case, the software of the image forming apparatus performs control in accordance with a predetermined identification definition. In other words, if the predetermined bit in the memory unit is 1, it is possible to control the type by determining the type, such as a standard toner cartridge, and if it is 0, a highly fluid toner cartridge, and switching the calculation table of FIG. is there. However, in this case, the identification method must be determined, and if the developing device 14 having different fluidity and permeability toner characteristics is manufactured after the product is released, the remaining amount of toner cannot be detected well, so the versatility is low. .
[0030]
Therefore, in the present invention, the slope and intercept of the graph, which are parameters for calculating a detection table that differs for each color depending on the difference in toner characteristics, are stored in the memory unit 101 of the developing device 14. In this way, it is not necessary for the software of the image forming apparatus to define an identification method, and the toner characteristics of the developing device 14 can be changed even after the image forming apparatus is released. Furthermore, even if the characteristics of the toner change due to improvements in the toner, and the slope and intercept of the toner remaining amount detection graph change, it was assumed that this detection accuracy would not be changed in the past. Although the change of fluidity due to the change of the agent and the change of the transmittance due to the improvement of the toner could not be performed, according to this method, each of the developing devices 14 having different characteristics is optimally detected and controlled. Therefore, if the detection parameters are changed at the same time, a system that can change the toner remaining amount detection without any problem is realized.
[0031]
As a specific setting, when actual detection is performed, it is a function of transmission time and usage rate as shown in FIG.
[0032]
In other words, with an ordinary toner cartridge,
Transmission time duty (%) = 100/80 × utilization rate (%) − 25
It is only necessary to store the inclination 100/80 and the intercept -25.
[0033]
Also, with toner cartridges with high fluidity,
Transmission time duty (%) = Usage rate (%)
With slope 1 and intercept 0.
[0034]
Also, with toner cartridges with high fluidity and transmittance,
Transmission time duty (%) = 70/100 × Usage rate (%) + 30
It is only necessary to store the inclination 70/100 and the intercept +30.
[0035]
From this information, the CPU 303 can calculate the usage rate from the transmission time, and since the cartridge stores its own detection coefficient in the nonvolatile memory, the control conditions of the image forming apparatus main body can be made variable. Even when the developing devices 14 having different characteristics are used, the respective toner remaining amounts can be detected optimally.
[0036]
Such a method may be approximated by a linear function as in this embodiment, or may be approximated by another function such as an exponential function or a logarithmic function.
[0037]
(Embodiment 2)
A second embodiment of an image forming apparatus to which the present invention is applied will be described below. Detailed description of the same parts as those in the first embodiment will be omitted.
[0038]
FIG. 9 shows an image forming apparatus according to the second embodiment.
[0039]
The non-volatile memory unit 101 of the exchange unit described in the first embodiment can be realized by a normal EEPROM as shown in FIG. The CPU and the memory unit 101 mounted on the developing unit 14 are connected by a drawer connector or the like provided so as to be fitted to the developing unit 14 and the detachable part of the image forming apparatus main body. A system in which an electrical contact is configured and connected between the replacement unit and the image forming apparatus main body without using a drawer connector is also possible. In this way, the same toner remaining amount detection control can be performed even in a contact-type nonvolatile memory system mounted on a replacement unit that has been conventionally implemented.
[0040]
Since the details of the control are the same as those in the first embodiment, description thereof is omitted.
[0041]
(Embodiment 3)
A third embodiment of an image forming apparatus to which the present invention is applied will be described below. Detailed description of the same parts as those in the first embodiment will be omitted.
[0042]
As a third embodiment, a method of directly storing parameters used for control conditions as information to be stored in the nonvolatile memory unit 101 of the replacement unit described in the first and second embodiments is simple. A method of compressing data is often used. For example, if it is possible even if the resolution is reduced or if a discontinuous value is sufficient, the number of bits can be reduced even if the set value is provided with 8 bits and has a setting from 0 to 255. Of course, in this case, the main body of the image forming apparatus performs a predetermined multiplication on the information in the nonvolatile memory unit and handles it as a control set value.
Since the details of the control are the same as those in the first embodiment, description thereof is omitted.
[0043]
【The invention's effect】
As described above, according to the present invention, by storing a plurality of parameters corresponding to the characteristics of the developer of different colors in the nonvolatile memory of the developer as an exchange unit, the different colors stored in the developer are stored . Even when the characteristics such as toner fluidity and permeability are different, the remaining amount can be detected with the remaining amount detection parameter optimum for each developing device. In other words, improvement of the toner stored in the developing device, by changing the toner to improve, so that even when the would change and fluidity and permeability, in accordance with the fluidity and permeability of each toner If a plurality of parameters of the nonvolatile memory are optimized, the accuracy of toner remaining amount detection can be maintained and improved.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an image forming apparatus of the present invention.
FIG. 2 is a configuration diagram of an image forming apparatus of the present invention.
FIG. 3 is an explanatory diagram of a scanner unit portion of the image forming apparatus of the present invention.
FIG. 4 is a configuration explanatory diagram of a developing device and a memory unit.
FIG. 5 is a configuration diagram of an amplifier circuit unit.
FIG. 6 is a configuration diagram of a receiving circuit unit.
FIG. 7 is a configuration diagram of a communication unit in the image forming apparatus of the present invention.
FIG. 8 is a configuration diagram of a remaining amount detection unit.
FIG. 9 is an explanatory diagram of an image forming apparatus according to a second embodiment of the present invention.
FIG. 10 is an explanatory diagram of an image forming apparatus of the present invention.
FIG. 11 is an explanatory diagram of signal processing of a remaining amount detection unit.
FIG. 12 is a characteristic diagram of a usage amount and a detection signal.
FIG. 13 is a characteristic explanatory diagram of transmission time.
[Explanation of symbols]
11 Scanner unit 13 Laser light 13
14 Developing Device 15 Cleaning Device 17 Developing Roller 18 Photosensitive Drum (Image Carrier)
20 Conveying belt 22 Cassette 23 Fixing device 29 Transfer material 31 Semiconductor laser 32 Collimator lens 33 Cylindrical lens 34 Polygon mirror 35 Scanner motor 36 Spherical lens 37 Fθ lens 38 Deflection mirror 39 Horizontal synchronization signal detector 101 Memory unit 102 Antenna unit 102
103 Communication Unit 104 Amplification Circuit 105 Communication IC
106 Analog Switch 107 Analog Switch 108 Reception Circuit 200 Operation Panel 201 Key Switch 203 Developer Change Door 204 Developer Check Switch 301 LED
302 Light receiving element 303 CPU
304 Stir plate

Claims (1)

A plurality of developers having a non-volatile memory for storing different color developers and storing a plurality of parameters corresponding to the characteristics of the different color developers can be attached and detached, and the light emitting elements and the light emitting elements are connected to image signals. A plurality of exposure means for emitting light based on the light, a plurality of image carriers forming an electrostatic latent image by light emitted from the light emitting element, and a developer attaching the developer to the electrostatic latent image by the developing unit. An image forming apparatus comprising: a plurality of transfer units that transfer an image formed on the image bearing member to a transfer material by means of; and a fixing unit that fixes the image transferred on the transfer material by heating and pressing. ,
Stirring means for stirring the developer in the developing unit;
While the developer in the developing device is being stirred by the stirring means, the transmission time of light passing through the developing device is detected by an optical detection method, and light detection is performed according to the remaining amount of the developer in the developing device. A developer remaining amount detecting means for outputting a signal;
The plurality of parameters according to the characteristics of the developer of the different color is a plurality of parameters for calculating the remaining amount of the developer according to the fluidity of the developer of the different color or the fluidity and permeability. Because
The light detection signal output by the developer remaining amount detecting means and the flowability of the different color developer stored in the non-volatile memory of the developer, or a plurality of parameters according to the flowability and permeability An image forming apparatus comprising: a calculation unit that calculates a remaining amount of developer in the developing device using a linear function based on the linear function.

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