# US 10,310,434 B1 · Image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,434 B1 - Document ID: US10310434B1 - Status: Granted - Kind: B1 - Application number: 16/171,949 - Filed: 2018-10-26 - Published: 2019-06-06 - Granted: 2019-06-04 - Earliest claimed: 2017-12-01 - Assignees: Konica Minolta, Inc. - Applicants: Konica Minolta Inc. - Inventors: Yu Mukobayashi - Web page: https://patentgrep.com/patent/US10310434B1 ## CPC - G03G 15/553: {Monitoring or warning means for exhaustion or lifetime end of consumables, e.g. indication of insufficient copy sheet quantity for a job} - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract An image forming apparatus includes: photoconductors rotatable and having toner images to be formed on surfaces; a transfer belt on which the toner images formed on the photoconductors are sequentially transferred; and a hardware processor that estimates timing of arrival of end of life of one photoconductor of the photoconductors due to depletion of the surface of the one photoconductor, wherein the hardware processor calculates a depletion amount of the one photoconductor due to a toner, as a first depletion amount, based on a first parameter having a positive correlation with an amount of the toner used for the toner image formed on the surface of another photoconductor that transfers the toner image on the transfer belt before the one photoconductor, and compares the calculated first depletion amount with a predetermined life estimation threshold value to estimate the timing of arrival of end of life of the one photoconductor. ## Claims ### Claim 1 An image forming apparatus comprising: a plurality of photoconductors that is rotatable and has toner images to be formed on respective surfaces; a transfer belt on which the toner images respectively formed on the plurality of photoconductors are sequentially transferred; and a hardware processor that estimates timing of arrival of end of life of one photoconductor of the plurality of photoconductors due to depletion of the surface of the one photoconductor, wherein the hardware processor calculates a depletion amount of the one photoconductor due to a toner, as a first depletion amount, on the basis of a first parameter having a positive correlation with an amount of the toner used for the toner image formed on the surface of another photoconductor that transfers the toner image on the transfer belt before the one photoconductor, and compares the calculated first depletion amount with a predetermined life estimation threshold value to estimate the timing of arrival of end of life of the one photoconductor. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein the first parameter includes an operation amount of the another photoconductor and a printing rate of when the toner image is formed on the surface of the another photoconductor. ### Claim 3 (depends on 2) The image forming apparatus according to claim 2, wherein the operation amount includes an integrated value of rotation numbers of the photoconductor or an integrated value of rotation times of the photoconductor. ### Claim 4 (depends on 2) The image forming apparatus according to claim 2, wherein the printing rate is calculated according to a dot count of the toner of when the toner image is formed on the surface of the photoconductor. ### Claim 5 (depends on 1) The image forming apparatus according to claim 1, wherein the hardware processor further calculates the depletion amount of the one photoconductor due to a toner, as a second depletion amount, on the basis of a second parameter having a positive correlation with an amount of the toner used for the toner image formed on the surface of the one photoconductor, calculates an integrated value of the first depletion amount and the second depletion amount, and compares the calculated integrated value with a predetermined life estimation threshold value to estimate the timing of arrival of end of life of the one photoconductor. ### Claim 6 (depends on 5) The image forming apparatus according to claim 5, wherein the second parameter includes an operation amount of the one photoconductor and a printing rate of when the toner image is formed on the surface of the one photoconductor. ### Claim 7 (depends on 5) The image forming apparatus according to claim 5, wherein, in a case where there is a plurality of the other photoconductors, the hardware processor calculates the first depletion amount such that the depletion amount of the one photoconductor due to the toner used for the toner image formed on the surface of another photoconductor becomes larger, the another photoconductor transferring the toner image on the transfer belt earlier than the plurality of the other photoconductors. ### Claim 8 (depends on 5) The image forming apparatus according to claim 5, wherein the photoconductor has a cylindrical shape, and the hardware processor calculates the integrated value for each of a plurality of sections in a cylinder axis direction of the photoconductor. ### Claim 9 (depends on 1) The image forming apparatus according to claim 1, wherein the hardware processor further corrects an estimation result of the life on the basis of an operation amount of a consumable member provided in the image forming apparatus. ### Claim 10 (depends on 9) The image forming apparatus according to claim 9, wherein the consumable member is a developer that forms the toner image on the surface of the photoconductor, and the operation amount includes any one of the number of printed sheets in the image forming apparatus, a rotation number of a developing roller provided in the developer, and a rotation time of the developing roller. ### Claim 11 (depends on 9) The image forming apparatus according to claim 9, wherein the consumable member is the transfer belt, and the operation amount includes any one of the number of printed sheets in the image forming apparatus, a traveling distance of the transfer belt, and a traveling time of the transfer belt. ### Claim 12 A non-transitory recording medium storing a computer readable control program for life estimation of an image forming apparatus, the image forming apparatus including a plurality of photoconductors that is rotatable and has toner images to be formed on respective surfaces, a transfer belt on which the toner images respectively formed on the plurality of photoconductors are sequentially transferred, and a hardware processor that estimates timing of arrival of end of life of one photoconductor of the plurality of photoconductors due to depletion of the surface of the one photoconductor, the control program causing the hardware processor to perform: calculating a depletion amount of the one photoconductor due to a toner, as a first depletion amount, on the basis of a first parameter having a positive correlation with an amount of the toner used for the toner image formed on the surface of another photoconductor that transfers the toner image on the transfer belt before the one photoconductor; and comparing the calculated first depletion amount with a predetermined life estimation threshold value to estimate the timing of arrival of end of life of the one photoconductor. ### Claim 13 A life estimation device for life estimation of an image forming apparatus, the image forming apparatus including a plurality of photoconductors that is rotatable and has toner images to be formed on respective surfaces, and a transfer belt on which the toner images respectively formed on the plurality of photoconductors are sequentially transferred, the life estimation device comprising: a hardware processor that estimates timing of arrival of end of life of one photoconductor of the plurality of photoconductors due to depletion of the surface of the one photoconductor, wherein the hardware processor calculates a depletion amount of the one photoconductor due to a toner, as a first depletion amount, on the basis of a first parameter having a positive correlation with an amount of the toner used for the toner image formed on the surface of another photoconductor that transfers the toner image on the transfer belt before the one photoconductor, and compares the calculated first depletion amount with a predetermined life estimation threshold value to estimate the timing of arrival of end of life of the one photoconductor.