A measurement device includes: a resistance measurement unit that measures an electrical resistance of a measurement target; a first measurement unit, including a detector that detects information indicating a first physical property other than the electrical resistance of the measurement target, that measures the first physical property from a detection result from the detector; a second measurement unit, including a detector that detects information indicating a second physical property other than the electrical resistance and the first physical property of the measurement target, that measures the second physical property from a detection result from the detector, in which a length of time from a start of driving the detector until a start of actual measurement is longer in the second measurement unit than in the first measurement unit; and a control unit that performs first control causing the first measurement unit to execute a measurement operation of measuring the first physical property in parallel with a measurement operation by the resistance measurement unit, and performs second control causing the second measurement unit to execute a measurement operation of measuring the second physical property in parallel with the measurement operation by the resistance measurement unit and also causing the second measurement unit to start the driving of the detector in the second measurement unit before the start of the driving of the detector in the first measurement unit.

An image reading apparatus includes a transparent member, a conveyance unit, a reading unit reading an image information through the transparent member from the sheet conveyed by the conveyance unit, and a guide member provided upstream of a reading position where the reading unit reads the image information from the sheet with respect to a sheet conveyance direction. The guide member includes a sheet-like sheet member having elasticity. A leading end of a downstream side of the guide member in the sheet conveyance direction is a folded portion formed by folding back the sheet member.

A sensor control apparatus includes a control unit, a plurality of sensors connected in series to the control unit. Each of the plurality of sensors includes a detector configured to perform a detection operation based on a first voltage applied from the control unit, a first switch provided on an application path for applying a voltage, a second switch provided on a supply path for supplying the voltage applied from the control unit to a sensor connected in a subsequent stage, and a conduction control unit. The control unit brings the first switch into conduction and cut off the second switch in a case where the voltage on the application path is the first voltage, and cuts off the first switch and bring the second switch into conduction in a case where the voltage on the application path is a second voltage.

An example print apparatus is described as including a fuser roller, a pressure device that generates wear on a section of the fuser roller surface, and a wear detection engine that identifies a degree of wear on the surface of the fuser roller. An example fuser roller may include a tube, a heating element, and a plurality of layers having a detectable pattern. An example print apparatus may include a wear detection engine having an emitter, a detector, and a controller that identifies a wear pattern based on data provided by the detector in response to activation of the emitter and determines a degree of wear based on the identified wear pattern.

An image forming apparatus includes an image bearing member, an image forming unit, a detection unit, and a control portion. The detection unit includes a casing, an optical sensor, a shutter portion, a moving member, a groove portion, and a projection portion. The optical sensor is disposed within the casing facing the image bearing member to detect the toner image and comprises a light emitting portion emitting light to the image bearing member through the opening portion and a light receiving portion receiving the light reflected from the image bearing member. The shutter is configured to open/close the opening portion as the projection portion moves in a direction intersecting with the predetermined direction as the moving member moves in the predetermined direction. The groove portion is disposed perpendicularly above an extension line of an optical axis of the light irradiated from the light emitting portion to the image bearing member.

An image abnormality detecting device includes an image reader, an abnormality detector, a pattern holder, and circuitry. The image reader is configured to read an image on a recording medium. The abnormality detector is configured to detect abnormality of the image based on read information of the image on the recording medium, read by the image reader. The pattern holder has a check pattern and is disposed within a reading area of the image reader. The circuitry is configured to inspect a detecting operation of the abnormality detector based on read information of the check pattern read by the image reader.

A cam transmits and blocks light emitted from a light emitting portion. The cam moves to: a first position at which first and second cartridges are attachable to and detachable from a housing; a second position at which a first development roller contacts a first photosensitive drum, the second position being a position at which the cam has moved in a first direction from the first position; and a third position at which the first development roller is separated from the first photosensitive drum and a second development roller is separated from a second photosensitive drum, the third position being a position at which the cam has moved in the first direction from the second position. During an initial operation, based on a detection result of the sensor, a controller determines which of the first position, the second position, and the third position the cam is located at.

An image reading apparatus includes a conveyance unit, a first reading unit, a first guide portion, a second reading unit, and a second guide portion. The second reading unit includes a rectangular transparent member, an optical reading unit, a housing, a first and a second contact portions, a first and a second pressing members, and a protruding portion. The first and the second contact portions are protruding from a facing surface of the housing. The protruding portion, when viewed from an upstream side in a conveyance direction of a recording material passing through a conveyance path between the second reading unit and the second guide portion, is disposed between the first contact portion and the second contact portion and protruding from the facing surface of the housing, a protruding amount of the protruding portion being smaller than protruding amounts of the first and the second contact portions.

A loop detection unit including a first contact portion in contact with a back surface of the recording material. A residual sheet detection unit including a second contact portion that is configured to come into contact with the back surface of the recording material. The first contact portion and the second contact portion are configured to rotate on the same rotation shaft. The second contact portion is configured to come into contact with the back surface of the recording material on a downstream of the first contact portion in the conveyance direction of the recording material.

An image forming apparatus and method are disclosed. A detection light is radiated to a medium. An amount of transmitted light, an amount of regular reflected light, and an amount of diffuse reflected light are detected. A reflected-light-amount-equivalent value is obtained when the amount of regular reflected light is standardized based on the amount of diffuse reflected light. A glossy sheet-thickness coefficient is calculated by adding the reflected-light-amount-equivalent value to a transmitted-light-amount-equivalent value that is based on the amount of transmitted light. The weight property of the medium is determined, based on the glossy sheet-thickness coefficient, wherein the weight property comprises a basis weight or a thickness of the medium.