An image forming apparatus includes a conveying unit, an image forming unit, a fixing unit, a first driving unit, a second driving unit, a transmission unit to transmit an ultrasonic wave, and a reception unit. Where a determination is made that a timing at which excitation of the first driving unit is switched or a timing at which excitation of the second driving unit is switched overlaps with a timing to obtain a value of the ultrasonic wave received by the reception unit, the transmission unit does not transmit an ultrasonic wave. Where a determination is made that the timing at which the excitation of the first driving unit is switched or the timing at which the excitation of the second driving unit is switched does not overlap with the timing to obtain the value of the received ultrasonic wave, the transmission unit transmits an ultrasonic wave.

An image forming apparatus includes a first detector detecting an operation sound based on a sound wave received by a receiver; a second detector detecting basis weight of recording material based on an ultrasonic wave transmitted from a transmitter and received by the receiver; a switching unit that switches destination of a reception signal from the receiver between a first path to the first detector and a second path to the second detector; and a controller that controls the switching unit such that the reception signal is output to the first path at a first timing and to the second path at a second timing. When a predetermined condition is satisfied, the controller controls the switching unit such that the reception signal is output to the second path at the first timing or to the first path at the second timing.

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.

An image forming apparatus includes a conveying unit, an image forming unit, a fixing unit, a first driving unit, a second driving unit, a transmission unit to transmit an ultrasonic wave, and a reception unit. Where a determination is made that a timing at which excitation of the first driving unit is switched or a timing at which excitation of the second driving unit is switched overlaps with a timing to obtain a value of the ultrasonic wave received by the reception unit, the transmission unit does not transmit an ultrasonic wave. Where a determination is made that the timing at which the excitation of the first driving unit is switched or the timing at which the excitation of the second driving unit is switched does not overlap with the timing to obtain the value of the received ultrasonic wave, the transmission unit transmits an ultrasonic wave.

An image forming apparatus includes a first detector detecting an operation sound based on a sound wave received by a receiver; a second detector detecting basis weight of recording material based on an ultrasonic wave transmitted from a transmitter and received by the receiver; a switching unit that switches destination of a reception signal from the receiver between a first path to the first detector and a second path to the second detector; and a controller that controls the switching unit such that the reception signal is output to the first path at a first timing and to the second path at a second timing. When a predetermined condition is satisfied, the controller controls the switching unit such that the reception signal is output to the second path at the first timing or to the first path at the second timing.

An image forming apparatus that forms an image on a recording material has a second image forming mode that (i) controls the target control temperature of a heater to be lower than in a normal image forming mode and at least (ii) extends a period of time from the start of image forming to a point of time at which the recording material reaches the nip portion to be longer than in the normal image forming mode based on (A) recording material information indicating the hardness of the recording material, at least one of (B) margin information indicating the size of the margin at the leading end in the transport direction of the recording material and (C) toner amount information at the leading end of the image formed on the recording material, and (D) information of an environment in which the image forming apparatus is installed.

An image forming apparatus includes: an image forming unit configured to form an image on a recording material based on first image data; a controller configured to control an image forming operation by the image forming unit; an acquisition unit configured to acquire property information related to a property of the recording material; a setting unit configured to set a control value to be used in the image forming operation; a reader configured to read an image formed on the recording material by the image forming unit, and to output second image data; and a comparison unit configured to compare the first image data to the second image data, wherein the setting unit is further configured to set the control value based on a comparison result from the comparison unit and the property information.

An image forming apparatus includes an image forming portion, a rotatable intermediary transfer belt, a plurality of stretching rollers, an outer roller, a moving mechanism, and a controller. In a case that a basis weight of a first recording material is a first basis weight and a basis weight of a second recording material is a second basis weight larger than the first basis weight, a position of the inner roller is the second position when the toner image is transferred onto the second recording material, and in a case that the basis weight of the first recording material and the basis weight of the second recording material are the second basis weight, the position of the inner roller is the first position when the toner image is transferred onto the second recording material.

A recording material determination apparatus includes a transmission unit, a reception unit, and a determination unit. The transmission unit transmits an ultrasonic wave to a recording material. The reception unit vibrates when the reception unit receives the ultrasonic wave having been transmitted from the transmission unit and having passed through the recording material, and outputs a signal corresponding to a vibration state. The determination unit determines a basis weight of the recording material in accordance with the signal output from the reception unit. A resonance frequency of the reception unit differs from a resonance frequency of the transmission unit, and the reception unit is capable of receiving a sound wave in an ultrasonic range and a sound wave in an audible range.

An image forming apparatus detects an attribute of paper for each sheet of paper. A post-process apparatus performs a post-process for each group of paper including a designated number of sheets of paper. A controller of the image forming apparatus determines for each sheet of paper, whether or not a designated post-process is prohibited based on prohibition rule data which defines permission and prohibition of the post-process in accordance with the attribute of paper for each type of post-process and the detected attribute of paper. When the controller determines that the designated post-process is prohibited, the controller determines whether or not a sheet of paper which resulted in determination as prohibition is a sheet of paper intermediate between the first sheet of paper and the last sheet of paper in the group of paper, and has an image forming system perform a process in accordance with a result of determination.