JP2009015046A - Developer deterioration measuring device, image forming apparatus mounting the device, maintenance management system having image forming apparatus, and maintenance management method for image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the image forming apparatus or the like having a function of: detecting deterioration of used developer so that a user replaces the used developer with fresh developer at an appropriate time before image quality degrades due to a change in charging of toner as a result of developer deterioration; and informing a user of the degree of developer deterioration. <P>SOLUTION: The developer deterioration measuring device measures the deterioration of developer composed of two components: carrier and toner. The device calculates the electrostatic capacity value of carrier present on the developing sleeve of an image forming apparatus after development. The device measures the deterioration of developer by comparing that value with the electrostatic capacity value of unused carrier. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developer deterioration state measuring device for detecting a developer deterioration state that can be mounted on an image forming apparatus such as a copying machine or a printer that forms an image using toner, an image forming apparatus equipped with the device, The present invention relates to a maintenance management system having an image forming apparatus and a maintenance management method for the image forming apparatus.

  Conventionally, in an electrophotographic system using a two-component developer, a so-called two-component developer comprising a magnetic carrier and fine toner is used. In this method, the carrier and toner are agitated and rubbed to impart a desired charge amount to the toner, and the latent image on the latent image carrier is developed with the charged toner. Therefore, in such an electrophotographic system using a two-component developer, the carrier that gives the toner a permanent and stable charge amount over a long period of time maintains its ability. It is important for life.

  Such a two-component developer is usually magnetically adsorbed on a rotating developer carrying member, conveyed to the vicinity of the photosensitive member, and developed. In general, a developer carrying member uses a fixed or rotating magnet and a circumferential or belt-like sleeve that rotates on the outside thereof. When the relative positional relationship between the magnet and the sleeve changes, the developer on the sleeve is conveyed while being swung in accordance with the change in the magnetic field. In addition, the developer that has been developed is quickly removed from the sleeve, and new developer is continuously supplied to the developing unit. The developed carrier is mixed and stirred again with the toner, and is repeatedly supplied to the developing unit. Thereafter, image formation is similarly performed.

In this way, the carrier used for development is repeatedly agitated and mixed with the toner without being consumed during the use of the image forming apparatus. As a result, it is inevitable that the charge imparting ability at the beginning of use varies due to wear and peeling of the composition on the carrier surface.
In such an apparatus using two-component toner, toner is consumed when repeated development is performed. Therefore, an apparatus for accurately detecting the toner density so as to maintain a constant toner density while supplying new toner is available. Are known. For example, as disclosed in Patent Document 1, a magnetic permeability sensor is incorporated in an image forming apparatus for detecting the toner concentration of a two-component developer, and is controlled so that the toner concentration of the developer is constant.

Further, as can be seen in Patent Documents 2 to 4 and the like, there is also known an invention in which the toner density is controlled from changes in the electrical resistance, dielectric constant, etc. of the developer.
The above-mentioned publicly known document is an invention in which new toner is replenished on the principle of the apparatus, and as a result, the toner concentration is maintained at an appropriate value, and the coating layer for protecting the magnetic powder of the carrier core as described above It can be said that there is no detection of the deterioration state by measuring the value of the amount of wear from the amount of electrical change. Therefore, it must be said that there is no invention which pays attention to the point which measures the deterioration state of a carrier correctly.
Thus, there is a need for a novel invention capable of accurately grasping the deterioration state of the developer and preferably notifying whether or not the life of the developer is informed or predicted.
Japanese Patent No. 342085 Japanese Patent No. 3387368 Japanese Patent Publication No. 63-066763 Japanese Patent Publication No. 63-208887

  According to the present invention, the developer used is deteriorated so that the developer used at an appropriate time is replaced with a new developer before the charge of the toner changes with the deterioration of the developer and the image quality is deteriorated. It is an object of the present invention to provide an invention such as an image forming apparatus having a function of detecting deterioration and notifying deterioration information such as how much the developer has deteriorated.

  As a result of intensive studies, the inventors have found that the electrostatic capacity of the developer changes due to the deterioration of the carrier resin layer, and if the change is monitored by some method, the deterioration state of the developer can be accurately measured. Further, by grasping the deterioration state of the developer, it becomes possible to predict or predict the deterioration of the developer. Specifically, the electrostatic capacity of the carrier existing on the developing sleeve in the image forming apparatus after toner development is obtained, and the initial electrostatic capacity of the mounted developer (initial value of electrostatic capacity: unused) The developer deterioration state measuring device to be compared with the developer's electrostatic capacity) has been invented.

  More specifically, the invention described in claim 1 is a developer deterioration state measuring device for measuring a deterioration state of a developer composed of two components of a carrier and a toner, and the developer deterioration state measuring device is an image. A capacitance value of the carrier after development existing on the developing sleeve of the forming apparatus is obtained, and a deterioration state of the developer is measured by comparing with a capacitance value when the carrier is not used. To do.

  According to a second aspect of the present invention, in the first aspect, the developer deterioration state measuring device includes an electrode provided opposite to the developing roller of the image forming apparatus and a voltage or a voltage between the electrode and the developing roller. It has an application means which applies electric power, and a means which measures the electric current at the time of applying by the said application means, It is characterized by the above-mentioned.

  According to a third aspect of the present invention, the image forming apparatus includes at least a charging unit for charging the photosensitive member, and a developing unit for developing the electrostatic latent image on the charged photosensitive member using a developer. The means is an image forming apparatus having a developing sleeve, and has the developer deterioration state measuring apparatus according to claim 1 or 2.

  According to a fourth aspect of the present invention, in the third aspect, the image forming apparatus has a function of notifying collection of at least one of a carrier and toner constituting the developer.

  According to a fifth aspect of the present invention, at least the image forming apparatus according to any one of the third to fourth aspects and a service-side terminal for performing management including maintenance and inspection of the image forming apparatus via a network. A connected maintenance management system, wherein the image forming apparatus obtains the capacitance of the carrier remaining on the developing sleeve in the apparatus to obtain the deterioration state of the two-component developer, and obtains the obtained result. Information to collect at least one of the carrier and toner constituting the two-component developer is transmitted to the service-side terminal, and the service-side terminal is notified of the developer based on the notification information of the image forming apparatus. The maintenance information is managed by transmitting prediction information of replacement or developer replacement timing.

  According to a sixth aspect of the present invention, there is provided a developer comprising two components of a carrier and a toner based on a capacitance value of the carrier existing on the developing sleeve in the image forming apparatus using the maintenance management system according to the fifth aspect. The maintenance management method using the maintenance management system is characterized in that the deterioration state of the image is obtained and the obtained result is notified to a service side terminal for management including maintenance and inspection of the image forming apparatus.

According to the image forming apparatus equipped with the developer deterioration state measuring apparatus of the present invention, it is possible to replace with a new developer at an appropriate time before the charge imparting performance to the toner of the carrier is lowered.
As a result, it is possible to prevent a phenomenon in which the image quality deteriorates with time due to a change in the toner charge amount, and to always realize a high-quality image that does not cause a decrease in image density even when used for a long time. An image forming apparatus capable of being provided can be provided.

  In addition, according to the present invention, a maintenance management system that does not bother the user with management or maintenance by grasping the state of deterioration of the developer in the image forming apparatus or predicting when it will be replaced is possible. In addition, it is possible to provide a developer recovery method and a maintenance management method that are preferable for the global environment.

The developer deterioration state measuring apparatus of the present invention has an electrode installed at a position facing the developing roller, and from the alternating current I when the alternating voltage V of the carrier existing between the two is applied, the ratio V / I Is measured, and the electrostatic capacity value C of the carrier is obtained by using a general formula, thereby measuring the deterioration state of the developer.
The capacitance value of the carrier tends to increase as the coating layer thickness decreases.

Therefore, how much the capacitance value C has increased, data at the time of shipment (initial value: capacitance of unused carrier), and carrier that has deteriorated due to use (for example, a magnetic layer without coating layer resin applied) The state of deterioration of the carrier can be detected by comparing the body carrier core material: the state of deterioration to the limit.
Also, by using the above-described apparatus for measuring AC impedance, the deterioration state of the carrier is accurately grasped, and the appropriate replacement time of the carrier is notified to the user and the administrator of the image forming apparatus. The present invention also includes a system and method related to maintenance of a developer and the like of a consumer material.

  The developer deterioration state measuring apparatus according to the present invention visually notifies (notifies) a user or the like via a display unit on the image forming apparatus based on such a change in the capacitance value of the carrier after development. Or the deterioration state of the developer can be accurately grasped and the progress of deterioration can be predicted. In addition, the present invention can have a function of, for example, when at least one of the two-component developer composed of toner and carrier is exchanged in a timely manner. In addition, the present invention provides an image forming apparatus equipped with such a developer deterioration state measuring apparatus, thereby providing an image forming apparatus that can stably provide a high-quality image even when used for a long time. it can.

First, the developer deterioration state measuring apparatus of the present invention will be described.
The developer deterioration state measuring apparatus of the present invention is mounted on an image forming apparatus.
As shown in FIG. 1, reference numeral 4 denotes a sensor electrode portion, and this electrode 4 is provided at a position facing a developing roller 2 which is a developing means of the image forming apparatus. For example, the installation position of the electrode 4 is set at a portion excluding from the developer conveyance start position by the developing roller 2 to the position closest to the photoreceptor 1 from the developer 1 to the development position by the developer described above. May be. The installation position of the electrode 4 is between the position after the closest position with the photosensitive member 1 in the developing roller and the vicinity of the developer storage container. More preferably, it is provided at a position facing the developing roller 2 until the carrier left after the end of the developing process is dropped and collected by its own weight from a position after the closest position to the photoreceptor 1 on the developing roller.

  As described above, the developer deterioration state measuring apparatus according to the present invention includes the electrode 4, voltage (power) applying means between the developing rollers 2, and means for measuring the value of a current flowing by application by the applying means. ing. The electrode of the developer deterioration state measuring apparatus of the present invention preferably measures a carrier that does not move when determining the capacitance value. For this reason, the electrostatic capacity value of the carrier can be obtained with the image forming apparatus stopped using the developer deterioration state measuring apparatus of the present invention. In the developer deterioration state measuring apparatus of the present invention, the electrode 4 can be fixed, and the capacitance value of the moving carrier can be obtained. Alternatively, the developer deterioration state measuring apparatus according to the present invention rotates the electrode 4 with the rotation of the developing roller 2 so as not to move relative to the carrier, and the capacitance value of the carrier in a state where the relative position does not change. It may be a device configured to measure.

  In such a developer deterioration state measuring apparatus, the electrode 4 is placed in parallel with the sleeve plane so as not to directly contact the developing sleeve, and an AC voltage V is applied between the electrode 4 and the developing roller 2. At that time, the alternating current I flowing between the electrode 4 and the developing roller 2 is measured, and the capacitance C1 is calculated from the ratio | Z | (impedance) with the voltage. The initial value C0 and the capacitance value C1 after lapse of time from the value obtained by subtracting the capacitance C0 of the initial value (ie, unused carrier) and the capacitance (blank) value Cb when there is no developer in the developing sleeve. Is obtained. Specifically, (C0−Cb) / (C1−Cb) = α is obtained. The developer measures in advance how much the value of α should be replaced due to the deterioration of the developer, or derives it from the empirical value to obtain αi that is within the allowable range (α that is the usable range). Keep it. Furthermore, in the present invention, either an upper limit value or a lower limit value of α, or two or more threshold values are provided, and at least one of the two or more threshold values is determined. If these values are specified and exceed or fall below these specified values, a warning can be displayed to the user, for example, or an appropriate developer replacement time can be notified to the user terminal. . In the embodiment, the range of α is changed when 0 <α <0.9, and when it is within this range, it is displayed as the carrier replacement time. However, since the range or value of α at the replacement time differs depending on the type of developer and the image forming apparatus, α is not limited to this range (value).

  The range of α or the α value of a usable carrier is obtained in advance by a developer or the like, and a value set by a numerical value of developer deterioration in each image forming apparatus is adopted. For example, at the beginning, the α value is 1, and the electrostatic capacity value C of the carrier becomes less than 1 and gradually decreases as the developer is used. When the α value of the carrier becomes a value smaller than 0.9, which is the use limit value, for example, 0.89, it can be determined that the developer cannot be used. That is, in the present invention, the deterioration state of the carrier can be obtained from the α value, and the developer can be managed by setting a certain use limit value αth. This determination based on αth is basically the same determination that α is in the range of 0 <α <0.9. That is, in the present invention, the use limit value αth is set, the α value of the carrier to be used is obtained, and this α value is compared with the use limit value αth to determine whether the developer can be used.

When the α value reaches the use limit value αth, the image forming apparatus of the present invention displays such information regarding the replacement of the developer on the operation panel screen or the display panel of the image forming apparatus. Thus, it is possible to notify the developer to be replaced.
At this time, for example, a notification method can be arbitrarily selected, for example, by emitting light in a different color to call attention. In the present invention, it is also possible to notify the user terminal connected to the image forming apparatus that the developer needs to be replaced.

  In the above description, an example is described in which the developer is replaced when the α value reaches a certain range, that is, when the carrier deterioration state is evaluated by the α value and the carrier reaches a certain deterioration state. did.

  In the present invention, as shown in the following examples, a commercially available device may be used as a device for measuring impedance. In the present invention, impedance is obtained by a known method, and the capacitance value is determined from the current value. You may measure using the apparatus (sensor) which can obtain | require. Further, in the present invention, the capacitance value is obtained by another method from the capacitance value C0 of the unused carrier immediately after the start of use and the capacitance value C of the carrier in use, and the above-described α value is obtained. It is possible to measure the deterioration state of the carrier in use.

  As described above, the image forming apparatus of the present invention has a function of determining deterioration of the carrier constituting the two-component developer from an electrical change amount and determining the recovery time of the developer, and developing in the apparatus. The deterioration state of the two-component developer is obtained based on the capacitance value of the carrier left on the sleeve, and the recovery of at least one of the carrier or toner of the two-component developer is notified using the obtained result. It is characterized by.

Next, examples of developers that can be measured in the present invention will be described. The developer that can be used in the present invention is a two-component developer. The two-component developer is composed of a carrier and a toner, and the carrier is a magnetic resin carrier in which ferrite, magnetite, or iron powder containing iron oxide as a main component is used as a core and coated with a resin.
Examples of such a carrier coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoropropylene Resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Fluoro such as terpolymers of emission and non-fluoride monomers including, and silicone resins.

  Further, the toner is not limited as long as it is a toner used as a two-component developer, but in the following examples, a toner composed of a binder resin, a colorant, a release agent, a charge adjusting agent, an external additive, and the like is used. used. As the binder resin, styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and the like, and substituted polymers thereof: styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer Polymer, styrene-vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methacrylic acid Methyl copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer Styrene-butadiene copolymer , Styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer and other styrenic copolymers: polymethyl methacrylate, polybutyl methacrylate, Polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon Examples thereof include resins, aromatic petroleum resins, chlorinated paraffins, and paraffin waxes, and these can be used alone or in combination of two or more.

  As the colorant, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide , Ocher, yellow lead, titanium yellow, oil yellow, Hansa yellow, (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R) ), Tartrazine Lake, Quinoline Yellow Lake, Anslagen Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Fire Red, Para Chlor ortho nitroaniline red, Sole Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigolet B , Thioindigo maroon, oil red, quinacridone red, pyrazolone red, chrome vermil , Benzine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, indanthrene blue (RS, BC ), Indigo, Ultramarine Blue, Bituminous Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxazine Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquinone Lean, titanium oxide, zinc white, lithopone and the like. These can be used alone or in combination of two or more.

  As the external additive, all known inorganic fine particles and hydrophobic treated inorganic fine particles can be used. For example, silica fine particles, hydrophobic silica, fatty acid metal salts (such as zinc stearate and aluminum stearate), metal oxides, and the like. (Titania, alumina, tin oxide, antimony oxide, etc.), fluoropolymers, etc. may be contained, and hydrophobized silica, titania, alumina fine particles are particularly suitable materials. In addition, as inorganic fine particles, for example, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite Diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride and the like. Of these, silica and titanium dioxide are particularly preferred.

  Examples of the release agent include solid paraffin wax, micro wax, rice wax, fatty acid amide wax, fatty acid wax, aliphatic monoketone, fatty acid metal salt wax, fatty acid ester wax, and partially saponified fatty acid ester wax. , Silicone varnish, higher alcohol, carnauba wax and the like.

As the material of the electrode 4 for measuring the impedance, all known conductive electrode materials can be used. Specifically, various conductive plates such as a copper plate, a platinum plate, a gold plate, various carbon plates, an iron plate, a nickel plate, a brass plate, and a stainless plate can be used.
The above conditions are examples of appropriate conditions of the present invention, and the present invention is not limited to these conditions.

<System having an image forming apparatus>
Next, an image forming system having the image forming apparatus of the present invention having the developer deterioration state measuring means as described above will be described below.
The system having the image system dispute device of the present invention has an image forming apparatus equipped with a developer deterioration state measuring device. This developer deterioration state measuring device is capable of measuring the carrier deterioration state of the two-component developer.

  The detection of the state of deterioration of the developer is preferably performed using the electrostatic capacitance value of the developer as described above. However, in the present invention, in addition to the monitoring of the capacitance value as described above, other capacitance-related values or related electrical quantities (for example, the change in the charge capacitance after applying vibration to the developer, the development The change of the developer compared with the unused developer by applying vibration to the developer, the time between the used developer and the unused developer until reaching a certain charge amount, etc.) It is also possible to monitor the degree of deterioration. In any case, the deterioration state of the developer is determined by comparing the unused developer and the used developer with the α ′ value ((unused Developer value-blank value) / (developer value after aging-blank value)). Such a α ′ value (α similarity value) is compared with a certain limit value α′th value to determine whether the α ′ value is larger or smaller than the limit value, and a two-component developer composed of carrier and toner. It is possible to determine whether or not at least one of the replacements is present or to predict the replacement timing.

  Such presence / absence determination can be performed by using an image forming apparatus as shown in FIG. It is also possible to determine whether or not to replace or to predict the replacement time on the host (host computer) side in the image forming system of the present invention or on the service center side described later.

  The image forming apparatus used in the image forming system of the present invention is only required to be connected to at least the host via the communication means. This connection may be wired or wireless, and any connection form may be used. The image forming apparatus used in this system preferably has a computer function. Furthermore, in the image forming apparatus maintenance and inspection system of the present invention, the image forming apparatus having at least the developer deterioration state measuring means as described above and the malfunction of the image forming apparatus are automatically monitored, and the user cannot cope with them. Service center (service center) connected via a communication line as described above in the event of an accident (for example, an incident that exceeds the accident on the image forming apparatus that can be easily processed by the user, such as changing only the developer) The system configuration is such that maintenance and inspection can be performed so that the terminal is preferably automatically informed to notify the accident that has occurred in the image forming apparatus and solve the accident that has occurred.

In the image forming apparatus (control unit) 100 in such a system, when a predetermined condition is reached, a command (degradation test command) for operating a program for measuring the state of deterioration of the developer is issued (FIG. 5 ( b) Start step S11).
Upon receiving this command, the image forming apparatus side 100 starts a program (step S11), executes a deterioration test, and measures the deterioration state of the developer (step S12).
The α ratio value as described above is calculated using the measured value. Next, the obtained α ratio value is referred to a table to determine whether the α ′ value is within the range (step S13). If the α ′ value is within the range, the developer is replaced ( Step S13 / Yes → Step S14), if no, the process ends (in the case of No in Step S13).

  In the present invention, the above-described program for measuring the state of deterioration of the developer may be preloaded in the image forming apparatus so that it can be activated at any time. The image forming apparatus may be preloaded or downloaded to the image forming apparatus, and the command may be issued or operated by the image forming apparatus main body with respect to the image forming apparatus, or may be resident in the image forming apparatus. May be.

  Next, carrier deterioration is selected from a plurality of measurement methods, and the α ′ value is calculated as described above. As a result, when the developer (or carrier) replacement is not necessary, this deterioration is performed. An example of a flow for predicting when the allowable range is exceeded will be described with reference to an invention such as a deterioration prediction method.

  Also in this flow, the operation from the start to the program activation is the same as shown in FIG. 5 (a) or (b). After that, determine which measurement method is used for the measurement, calculate the α ′ value of the developer at the present time, and as a result, determine whether the developer (or carrier) is replaced or not replaced. In this case, the replacement time is predicted and notified to the service center (service center terminal). If the developer (or carrier) replacement is selected in the above determination, at least the service center (service center terminal) is notified. Although an example in which the replacement time is predicted on the image forming apparatus side will be described, in the present invention, such prediction may be performed on the service center terminal side. In this case, data including the result of calculating the current α ratio value of the developer from the image forming apparatus and information on whether the developer (or carrier) is exchanged or not exchanged is sent to the service center.

On the service center side, from the data transmitted from the image forming apparatus, the user is notified of the replacement of the developer or the expected result of the replacement time to the user automatically or based on the contract, etc. Replace the agent (or carrier).
For example, as shown in FIG. 6, the operation from the start to the program activation is the same as that shown in FIG. Thereafter, it is determined by which measurement method the measurement is performed (step S22 in FIG. 6), the measurement is executed by the determined measurement method (step S23), and the above α ′ value is calculated based on the obtained value. Then, the α ′ value is recorded (step S24). Then, with reference to a table in which the recorded α ratio value is stored in advance, for example, in the storage means or the like, it is determined whether or not the α ′ value is within a predetermined range (step S26).

  If the result of this determination is that it is within the predetermined range (Yes in step S26), the developer (or carrier) is replaced (step S27) as in the case of Yes in step S2 or S13 in FIG. To do. If the result of this determination is not the predetermined range (No in step S26), the replacement time is predicted (step S28), and the predicted result is reported to at least the service center (service center terminal) ( Step S29) is ended.

  In step S22, it is assumed that, for example, a table of measurement methods is prepared and a plurality of measurement methods are prepared. The number of N is an integer of 2 or more. In the measurement methods prepared in the table, for example, the measurement methods are arranged in order of frequency, and in this case, the second measurement method is selected. In this case, first, it is determined whether or not the measurement is the first, that is, N = 1. Since this time is not, No is selected in step S22, N is incremented by one, and N = 2. Thus, it is determined again whether or not the measurement is N = 2. In this case, since the measurement method is N = 2, Yes is determined in step S22, and the process proceeds to step S23. As described above, when one of a plurality of measurement methods shown in FIG. 6 is selected, as described above until the target one is reached, in the case of No in step S22, an increment of No → N = N + 1 is performed. Done. When a plurality of measurements are selected, for example, when measurement method 1 and measurement method 3 are selected, step S22-1 for determining the presence or absence of another measurement is performed, for example, before or after step S23 or during execution. The measurement method 1 and the measurement method 3 are selected, and the measurement is performed simultaneously or at different measurement timings. From each measurement value, α1 which is the α ′ value in the measurement method 1 and the measurement method 3 The α ′ value α3 is calculated and recorded, and the corresponding α ranges are determined in the above-described step S26 with reference to, for example, a table. α1,..., αm (m is an integer) Based on a judgment table that takes all judgment formulas into account, the developer replacement or the like as shown in step S27 or the replacement time as shown in step S28 is predicted.

  In this way, by determining the deterioration of the developer by two or more measurement methods, it is possible to evaluate the replacement time in particular from a multifaceted perspective, or in some cases, the same measurement method is performed a plurality of times. Irregularity can be eliminated. In addition, according to the present invention, it is possible to predict and prevent a sudden accident, etc., and to evaluate the degree of deterioration and the prediction of the replacement time from various aspects, thereby evaluating the user. It is also possible to provide multi-faceted services.

  For example, based on a contract with the user, these measurements are performed during working hours or during the downtime, and the service center grasps the state of deterioration of the developer, etc., and the maintenance is performed during the user's holiday or downtime. Can also be executed. For this reason, this system can also prevent a user from being burdened when working. Note that the replacement time used in the flow as shown in FIG. 6 is affected by the use frequency of the user, the model, etc., and therefore it is preferable to make a prediction reflecting these conditions. For this reason, not only in the case of black, the use frequency of the developer of each component in the color can be automatically grasped at the service center, for example, and the degree of deterioration due to the use of the developer of each color is individually stored.

For example, when the deterioration of the developer is measured by changing the electrostatic capacity as shown in FIG. 7 and the carrier is exchanged or the like, for example, depending on the frequency of use, a tendency like a to d is shown. It is a deterioration curve in case c is an average use frequency. On the other hand, b is a deterioration curve when used at a frequency twice as high as the use frequency, and a shows a deterioration curve at the maximum use frequency. Moreover, d shows the tendency of the deterioration curve in the case of slow use frequency, for example.
The vertical axis in FIG. 7 represents the α ′ value described above.

In order to predict the replacement time using the curves a to d, for example, the following is performed.
On the image forming apparatus side, the usage time from the start of use is accumulated, and the measurement of the deterioration test of the developer or the like is started by a certain measuring method in order to calculate the α ratio value when a certain accumulated usage time is reached. . Then, as shown in and after step S23 in FIG. 6, an α ′ value is calculated based on the measured value, and this α ratio value is recorded (step S24). By this recording, the α ′ value and the time are recorded.

When the α ′ value is not within the range, in other words, when the developer or the like is not replaced, the replacement timing of the developer or the like is predicted. At this time, the relationship between the α ′ value and time is shown in FIG. 7 is predicted using a graph showing the relationship between the α ′ value and time shown in FIG.
For example, it is assumed that α ′ is 0.98 and the usage time is n1 hours. It is assumed that such a relationship between the α ′ value and time coincides with the value on the α′-time curve c in FIG.

Then, this c diagram is used for the prediction of the replacement time. For example, if the limit value is 0.91, the replacement time is obtained from the value of the limit value 0.91 from the c diagram, and the current n1 and Therefore, t4-n1 is predicted as the remaining predicted value from the current time to the replacement time. This value t4-n1 is communicated to at least one of the user terminal and the service center terminal (computer) via a communication network. When the variation in the usage frequency of the image forming apparatus is large, that is, in FIG. 7, the initial (for example, α1 to α5) can be plotted on the c diagram, but after α6 on the b diagram. When the frequency of use changes, such as when plotting is possible, prediction can be made using the b diagram.
As described above, this system can cope with changes in the frequency of use of the image forming apparatus, and is convenient for rationally reducing the initial performance of the image forming apparatus, the maintenance cost after use by the user, and the like.

  In particular, a plurality of threshold values are set from the initial α ′ value to the final α ′ value (the α ′ value of the replacement time) so that the service center is notified of the replacement when the degree of deterioration of the developer increases. (For example, 10 levels), only the first half (about 1 to 5 levels) is notified, and in the second half (for example, 6 to 10 levels, especially after 8 levels), more accurate prediction of replacement time is possible. As described above, it is also possible to consider the variation in the usage frequency from the time of use.

  For example, in the initial stage of use, the fitting to the c-curve is not performed from the state that can be plotted on the d-curve shown in FIG. And the replacement time may be predicted along this line (curve fitting method). In such a case where the frequency of use of the image forming apparatus is relatively low, it can be said that the deterioration rate of the developer is somewhat small, and the prediction of the replacement timing of the developer or the like in such an area is rather varied. By performing such curve fitting, if the frequency of use is low, or if there is a change in the frequency of use, the replacement time is more realistic in the latter half of the degraded area that deviates from the usable range after some degradation. Can be predicted. As such a curve fitting method, a known curve fitting method can also be used.

  Such a method such as curve fitting may be stored individually as a program on the image forming apparatus side, for example, or the user side or preferably the service center side is the distribution destination of the program, and the image forming apparatus The image forming apparatus sends the result information to the service center together with the MAC address, for example, and the service center calculates the deterioration degree of the developer in each image forming apparatus, such as the α ratio value. Management, or by providing failure prediction and maintenance information to the user, the management burden on the user side can be reduced and the work environment can be improved further. Note that other maintenance-related information of the image forming apparatus may be able to be performed on the service center side. In any case, in a system including an image forming apparatus, a system environment excellent in security can be provided by preventing an intrusion from a third party, an intrusion of an unauthorized program, and an unauthorized access. In addition, the system of the present invention can contribute.

  In the example described above, the example of predicting the degree of deterioration of the developer by the deterioration curve has been described as an example. However, the α′th value is obtained by experience or actual measurement in the same manner as the above-described use limit value αth. The value α′0 of the developer used is plotted with the change of the value α ′ due to use plotted with the horizontal axis as the operating time of the image forming apparatus and the vertical axis as α ′, and these plot points are determined by a method such as a least square method. It is also possible to predict the operation time of the image forming apparatus in which the extended line segment becomes the use limit value α′th by performing curve fitting using.

Further, according to the present invention, the use limit value is predicted based on the prediction as described above, and the unused developer value α′0 and use limit value α′th are divided into, for example, 10 to obtain the first 5 values. Until the division, the operation time of the image forming apparatus that will be the use limit value α′th is not predicted. In this period, the deterioration data of the developer used is collected every regular operation time, and in the latter half, for example, after 8 divisions, the service center side terminal can be alerted regarding the replacement timing.
Such replacement time prediction may be performed using two or more prediction methods when the second half is reached. These predictions can also be executed at the service center side terminal. The service center terminal can transmit information such as the position information of the image forming apparatus immediately before or immediately after the replacement time, the type of developer, and the replacement time to a portable terminal such as a service person.

Hereinafter, a developer deterioration state measuring apparatus and an image forming apparatus having the same according to the present invention will be described with reference to examples.
As shown in FIG. 1, the sensor 4 was installed in the immediate vicinity of the developing roller 2. When the carrier to be measured is sandwiched between the developing roller 2 and the counter electrode 4, a metal plate having a measurable electrode area of 8 cm 2 is installed so that the distance between the developing roller 2 and the counter electrode 4 is 2 mm. . An AC voltage of 5 V was applied between the electrodes, and the capacitance C of the carrier on the developing roller under each condition was determined from the impedance calculated from the current value flowing between the electrodes. The ratio of the difference between the capacitance C at this time and the capacitance (blank) value Cb when no developer is present in the developing sleeve and the difference between the value C0 and Cb at the time of shipment, specifically 0 When (<C0-Cb) / (C-Cb) = α <0.91, the replacement time is set.

The equivalent circuit in this case was calculated on the assumption that each sample between the electrodes has a resistance component and a capacitor component in parallel.
Case 1 shown in Table 1 is a measured value of the electrostatic capacity of the carrier when 190,000 sheets of development corresponding to a 20% solid image is performed in the image forming apparatus.
Case 2 is a measured value of the capacitance of the carrier when the image forming apparatus has developed 115,000 sheets corresponding to a solid image with an image portion of 0.5%.
Case 3 shows the capacitance of the carrier before deterioration, and Case 4 shows the capacitance of the core carrier not coated with resin. In Case 4, it can be assumed in a simulated manner that the coating layer resin is completely peeled off after being deteriorated in infinite time.

FIG. 2 shows a graph in which the deterioration state of case 1 is typically evaluated.
As shown in FIG. 2, the capacitance continuously changes in accordance with the deterioration state in the order of before deterioration (case 3) <deteriorated carrier (case 1) <after complete deterioration (case 4, core material). And after complete deterioration (case 4, core material), α is smaller than 0.91, indicating the replacement time accurately.

That is, from the verification of each case, the deterioration state of the carrier can be accurately detected by increasing the capacitance value, and the performance can be improved by measuring the capacitance of the carrier used in the image forming apparatus. It is possible to notify the user of an appropriate time to replace the carrier that has deteriorated and cannot be appropriately charged. The impedance of the sensor part was measured in a personal computer controlled environment by connecting the Solartron, 1260 type FRA (frequency generator), and 1296 type high impedance interface with the GPIB connection by the connection shown in Fig. 3. .
[Comparative example]

Case 5 shown in Table 2 is based on the impedance of the carrier when the image forming apparatus has developed 190,000 sheets corresponding to a solid image of 20% in the image forming apparatus, similarly to the experimental conditions introduced in the section of the embodiment. It is the calculated resistance value R.
Case 6 has a resistance value R calculated from the impedance of the carrier before deterioration, and Case 7 has a resistance value R calculated from the impedance of the core carrier not coated with the coat layer resin.

From the results of the table, the resistance values of the carrier before deterioration, the carrier of the deteriorated sample, and the carrier of the core material did not continuously change as in the capacitance values shown in the examples.
The reason for this is that the capacitance value can be calculated from the measured value in a high frequency region, and since a high frequency current may be used for the analysis, a relatively large current value can be used.
On the other hand, for the resistance value R, it is necessary to use a current in a low frequency region for analysis. In other words, the resistance value R can be determined by using an alternating current having a low frequency or a direct current.
A high resistance material such as a carrier has to analyze a weak current, so that an error of a measurement value becomes large, and it is estimated that a deterioration state is not properly evaluated.
From the above results, it was shown that it is preferable to use a capacitance value to detect the deterioration state.

FIG. 3 is a diagram illustrating an example of a main configuration (an installation position of a sensor, etc.) of an image forming apparatus of the present invention having a developer deterioration state measuring unit. It is an example figure which calculated | required the relationship between the deterioration state of a developer, and an electrostatic capacitance value using the image forming apparatus of this invention which has a developing agent deterioration state measurement means, and a vertical axis | shaft is a measured value of the electrostatic capacitance of a developer. The horizontal axis represents the difference in developer type (developer at the time of shipment from the time of complete deterioration) (a is the capacitance value at the time of shipment, and b is the capacitance value in a state deteriorated by use. , C are electrostatic capacity values in a state where only the core material has been completely degraded. It is a figure which shows the connection method of the sensor part used with the image forming apparatus of this invention which has a developing agent degradation state measurement means, and a measuring apparatus. 1 is a diagram illustrating a configuration example of an image forming system including an image forming apparatus having a developer deterioration state measuring unit. 3 is a flowchart showing a flow of a method for changing a developer and the like by measuring a developer deterioration state used in an image forming apparatus. 6 is a flowchart illustrating an execution flow in which a program for executing a method for measuring a developer deterioration state used in an image forming apparatus and changing a developer or the like is executed for the image forming apparatus and activated by the program. It is an example figure of the deterioration curve of a developer for estimating the time of changing a developer, a vertical axis is alpha ratio value, and a horizontal axis is time.

Explanation of symbols

1 Photoconductor
2 Developing roller
3 Developer storage container
4 Degradation state measurement sensor electrode
5 Impedance measuring instrument connection
6 (Type 1260) Frequency generator side connection terminal
7 (Type 1260) frequency generator

Claims (6)

A developer deterioration state measuring device for measuring a deterioration state of a developer composed of two components of a carrier and a toner,
The developer deterioration state measuring device obtains the capacitance value of the carrier after development existing on the developing sleeve of the image forming apparatus, and compares it with the capacitance value of the developer when not in use. A developer deterioration state measuring apparatus characterized by measuring a deterioration state. The developer deterioration state measuring device includes an electrode provided facing a developing roller of the image forming apparatus,
Applying means for applying a voltage or power between the electrode and the developing roller;
The developer deterioration state measuring apparatus according to claim 1, further comprising a unit that measures current when applied by the applying unit. An image forming apparatus having at least a charging unit for charging the photosensitive member, and a developing unit for developing the electrostatic latent image of the charged photosensitive member using a developer, the developing unit having a developing sleeve Because
An image forming apparatus comprising the developer deterioration state measuring device according to claim 1.   The image forming apparatus according to claim 3, wherein the image forming apparatus has a function of notifying collection of at least one of a carrier and toner constituting the developer. A maintenance management system in which at least the image forming apparatus according to any one of claims 3 to 4 and a service side terminal for performing management including maintenance and inspection of the image forming apparatus are connected via a network. ,
From the image forming apparatus, the capacitance of the carrier remaining on the developing sleeve in the apparatus is determined to determine the deterioration state of the two-component developer, and the two-component developer is configured using the obtained result. Notification information regarding at least one of carrier and toner collection is transmitted to the service side terminal, and the developer replacement or the developer replacement timing is predicted based on the notification information of the image forming apparatus to the service side terminal. A maintenance management system characterized by transmitting information for maintenance management.   Using the maintenance management system according to claim 5, the deterioration state of the developer composed of two components of the carrier and the toner is obtained from the capacitance value of the carrier existing on the developing sleeve in the image forming apparatus, and obtained. A maintenance management method using a maintenance management system, wherein a result is notified to a service side terminal for management including maintenance and inspection of the image forming apparatus.

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