Abstract: An image forming apparatus includes an image former that forms an image on a sheet of paper, a detector that detects a physical property of a sheet of paper, a receiver that receives paper identification information used in identification of a sheet of paper designated by a user, and a hardware processor. The hardware processor performs: first judgement of judging whether or not there is a correspondence between the paper identification information received by the receiver and a detection result by the detector, second judgement of judging whether or not there is a correspondence between a detection result by the detector of a first sheet of paper conveyed and a detection result by the detector of a second sheet of paper conveyed; and operation control of the image former based on a first judgement result in the first judgement and a second judgement result in the second judgement.

Abstract: Provided is an image forming system capable of accurately detecting the resistance of a recording material. The image forming system includes an application roller that applies a voltage to a recording material on a conveyance path, and a controller that calculates the electric resistance of the recording material from a relationship between the voltage applied to the application roller and a current. The controller calculates the resistance of the recording material based on first profile information that is acquired by changing the applied voltage and corresponds to a change in the resistance of the application roller, and second profile information that is acquired by changing the applied voltage in a state where the recording material is sandwiched and corresponds to the change in the resistance of the application roller.

Abstract: Provided are an image forming system and a method for detecting glossiness capable of accurately detecting glossiness in various media having different conditions. The image forming system includes a sensor unit including a light source that irradiates a medium being conveyed with light and a gloss sensor that receives light emitted from the light source and specularly reflected on the medium and detects a diffusion distribution of light in the medium, and a detection condition setting unit that identifies a type of the medium being conveyed and sets a light amount of the light source and/or exposure time of the gloss sensor at the time of glossiness detection in accordance with the type of the medium. The image forming system further includes a glossiness detector that detects glossiness of the medium from a diffusion distribution of light detected by the gloss sensor under the detection condition set by the detection condition setting unit.

Abstract: To provide a sheet conveyance device capable of preventing degradation in quality of conveying a sheet and image quality even when a stiffness of the sheet is different between a sheet conveyance direction and a sheet width direction. A sheet conveyance device of an image forming apparatus includes an image forming part that conveys a sheet along a conveyance path; and a stiffness acquisition part that acquires a stiffness of the sheet in a first direction including a component in the sheet conveyance direction by bending the sheet in the first direction, and acquires a stiffness of the sheet in a second direction including a component in the sheet width direction orthogonal to the sheet conveyance direction by bending the sheet in the second direction.

Abstract: Provided are an image forming system and a method for detecting glossiness capable of accurately detecting glossiness in various media having different conditions. The image forming system includes a sensor unit including a light source that irradiates a medium being conveyed with light and a gloss sensor that receives light emitted from the light source and specularly reflected on the medium and detects a diffusion distribution of light in the medium, and a detection condition setting unit that identifies a type of the medium being conveyed and sets a light amount of the light source and/or exposure time of the gloss sensor at the time of glossiness detection in accordance with the type of the medium. The image forming system further includes a glossiness detector that detects glossiness of the medium from a diffusion distribution of light detected by the gloss sensor under the detection condition set by the detection condition setting unit.

Abstract: A glossiness inspection device includes an illumination device that emits irradiation light to a glossiness detection target and a light receiving device that receives reflected light of the irradiation light reflected by the glossiness detection target and outputs a light reception detection signal according to an amount of the received light. A dimmer of the device adjusts an amount of the irradiation light, and a detection signal adjuster of the device adjusts a gain for amplifying the light reception detection signal. An irradiation position controller of the device selectively irradiates a first gloss region and a second gloss region of a correction plate with the irradiation light. A hardware processor of the device adjusts at least one of the amount of the irradiation light, an offset of the detection signal adjuster, a characteristic straight line for calculating a glossiness, or a calculated glossiness.

Abstract: To provide a sheet conveyance device capable of preventing degradation in quality of conveying a sheet and image quality even when a stiffness of the sheet is different between a sheet conveyance direction and a sheet width direction. A sheet conveyance device of an image forming apparatus includes an image forming part that conveys a sheet along a conveyance path; and a stiffness acquisition part that acquires a stiffness of the sheet in a first direction including a component in the sheet conveyance direction by bending the sheet in the first direction, and acquires a stiffness of the sheet in a second direction including a component in the sheet width direction orthogonal to the sheet conveyance direction by bending the sheet in the second direction.

Abstract: An image forming apparatus includes an image former that forms an image on a sheet of paper, a detector that detects a physical property of a sheet of paper, a receiver that receives paper identification information used in identification of a sheet of paper designated by a user, and a hardware processor. The hardware processor performs: first judgement of judging whether or not there is a correspondence between the paper identification information received by the receiver and a detection result by the detector, second judgement of judging whether or not there is a correspondence between a detection result by the detector of a first sheet of paper conveyed and a detection result by the detector of a second sheet of paper conveyed; and operation control of the image former based on a first judgement result in the first judgement and a second judgement result in the second judgement.

Abstract: A measuring device, includes a physical property value detector and a push contact member that pushes to bring a sheet material in contact with the physical property value detector; and further includes a first processor that stops conveyance of the sheet material, pushes to bring the sheet material in contact with the physical property value detector, and detects a physical property value of the sheet material; a second processor that, after having detected the physical property value, cancels the pushing by the push contact member, separates the sheet material from the physical property value detector, and starts conveyance of the sheet material; and a physical property value specifier that specifies the physical property value on a basis of physical property values of a plurality of positions within a surface of the sheet material detected by executing the first processing and the second processing repeatedly.

Abstract: A glossiness inspection device includes: an illumination device that emits irradiation light; a light receiving device that receives reflected light of the irradiation light reflected by a glossiness detection target and outputs a light reception detection signal according to an amount of the received light; a correction plate that includes at least a first gloss region and a second gloss region; a dimmer that adjusts an amount of the irradiation light; a detection signal adjuster that adjusts a gain for amplifying the light reception detection signal; an irradiation position controller that selectively irradiates the first gloss region and the second gloss region with the irradiation light; and a hardware processor that adjusts at least one of the amount of the irradiation light, an offset of the detection signal adjuster, a characteristic straight line for calculating a glossiness, or a calculated glossiness.

Abstract: An image forming apparatus includes: a conveyance path that conveys a sheet; registration rollers that are arranged across the conveyance path and each comprise a nip part; a sheet locking member that locks a front end of a sheet conveyed in the conveyance path, where the sheet locking member swings between a first attitude and a second attitude, in the first attitude the sheet locking member locks the sheet on an upstream side of the nip part, and in the second attitude the sheet locking member is retracted to a downstream side of the nip part and allows the sheet to pass through the nip part; an energizer that energizes the sheet locking member to maintain the first attitude; and a hardware processor that detects deterioration of the energizer.

Abstract: The present invention is directed to detect gloss of a toner image from which the influence of heat applied to a sheet by a fixing unit is eliminated. An image forming device according to an aspect of the invention includes: a gloss sensor irradiating a recording medium on which a toner image is formed and fixed with light, measuring reflectance of reflection light from the recording medium, and measuring gloss of the toner image on the basis of the reflectance; and a gloss correcting unit correcting the gloss of the toner image measured by the gloss sensor in a situation that the temperature of the toner image fixed on the recording medium is assumed to be higher than a predetermined threshold temperature or in the case where it is determined that the temperature of the toner image is higher than the predetermined threshold temperature.

Abstract: Provided is a recording medium detection device which prevents a recording medium from jamming. The device comprises: a first roller and a second roller which nip and transport a recording medium; a roller shaft which rotatably supports the second roller; a shaft support; and a displacement detector. The shaft support supports the roller shaft movably in the thickness direction of the recording medium. The displacement detector detects displacement of the second roller in the thickness direction. The shaft support further supports the second roller movably in the transportation direction of the recording medium through the roller shaft.

Abstract: Provided is a recording medium detection device which prevents the decline in productivity. The recording medium detection device comprises a first detecting section and a second detecting section. The first detecting section performs a first adjustment process and makes a detection of a recording medium being transported. The second detecting section is located more downstream than the first detecting section in the transportation direction of the recording medium, performs a second adjustment process which takes a longer time than the first adjustment process, and makes a detection of the recording medium being transported.

Abstract: A measuring device, includes a physical property value detector and a push contact member that pushes to bring a sheet material in contact with the physical property value detector; and further includes a first processor that stops conveyance of the sheet material, pushes to bring the sheet material in contact with the physical property value detector, and detects a physical property value of the sheet material; a second processor that, after having detected the physical property value, cancels the pushing by the push contact member, separates the sheet material from the physical property value detector, and starts conveyance of the sheet material; and a physical property value specifier that specifies the physical property value on a basis of physical property values of a plurality of positions within a surface of the sheet material detected by executing the first processing and the second processing repeatedly.

Abstract: An image forming apparatus includes: a conveyance path that conveys a sheet; registration rollers that are arranged across the conveyance path and each comprise a nip part; a sheet locking member that locks a front end of a sheet conveyed in the conveyance path, where the sheet locking member swings between a first attitude and a second attitude, in the first attitude the sheet locking member locks the sheet on an upstream side of the nip part, and in the second attitude the sheet locking member is retracted to a downstream side of the nip part and allows the sheet to pass through the nip part; an energizer that energizes the sheet locking member to maintain the first attitude; and a hardware processor that detects deterioration of the energizer.

Abstract: An image forming apparatus includes: a first rotor and a second rotor that are each a rotatable member; a first movable member including the first rotor or a transferer that transfers power of the first rotor to another member; a second movable member including the second rotor or a transferer that transfers power of the second rotor to another member; a hardware processor that drives simultaneously the first rotor and the second rotor at mutually different numbers of revolutions or speeds, and performs abnormality diagnosis on the first movable member and the second movable member, based on the sounds of operation acquired by the sound acquirer; and a sound acquirer that acquires sounds of operation of the first movable member and the second movable member with the first rotor and the second rotor being driven by the hardware processor.

Abstract: An image forming apparatus includes: a first rotor and a second rotor that are each a rotatable member; a first movable member including the first rotor or a transferer that transfers power of the first rotor to another member; a second movable member including the second rotor or a transferer that transfers power of the second rotor to another member; a hardware processor that drives simultaneously the first rotor and the second rotor at mutually different numbers of revolutions or speeds, and performs abnormality diagnosis on the first movable member and the second movable member, based on the sounds of operation acquired by the sound acquirer; and a sound acquirer that acquires sounds of operation of the first movable member and the second movable member with the first rotor and the second rotor being driven by the hardware processor.

Abstract: An abnormality determination apparatus includes: an audio data acquisitor that acquires audio data of an apparatus to be judged for determining presence or absence of abnormality; an abnormal sound detector that detects an abnormal sound based on the audio data acquired by the audio data acquisitor; and a hardware processor that determines whether the abnormal sound is such a sound that an operation of the apparatus to be judged should be restricted based on a subsequent secular change of the abnormal sound when the abnormal sound is detected by the abnormal sound detector, and restricts the operation of the apparatus to be judged when the hardware processor determines that the abnormal sound is such a sound that the operation of the apparatus to be judged should be restricted.

Abstract: A phase control device includes: at least one switching element connected to an AC power source, the switching element being capable of: turning on and off at specified timings; delivering AC power to a load upon turn-on and cutting it off upon turn-off; and keeping an on-time from the start to the end of turn-on and an off-time from the start to the end of turn-off, the on-time and off-time being variable; a timing setting portion that sets a turn-on and turn-off timing for turning on and off the switching element; a judgment portion that judges whether or not the turn-on and turn-off timing are on at a phase within a first or second phase range; and a processor that starts turning on and off the switching element at the turn-on and turn-off timing, the processor being capable of adjusting the on-time and off-time depending on the judgment result.