A paper warping detection device includes an input tray, a processor, a first emitting element, a first receiving element and a first analog-to-digital converter. A first critical value is stored in the processor. The first emitting element is electrically connected with the processor. The first receiving element is disposed to the other side of the input tray. The first receiving element and the first emitting element face each other. When the first emitting element is switched on, the first emitting element emits first ultrasonic wave signals towards the first receiving element. The first analog-to-digital converter is electrically connected with the first receiving element and the processor for converting the first ultrasonic wave signals into first digital signals and outputting the first digital signals to the processor. The processor reads the first digital signals and compares the first digital signals with the first critical value.

A paper warping detection device includes an input tray, a processor, a first emitting element, a first receiving element and a first analog-to-digital converter. A first critical value is stored in the processor. The first emitting element is electrically connected with the processor. The first receiving element is disposed to the other side of the input tray. The first receiving element and the first emitting element face each other. When the first emitting element is switched on, the first emitting element emits first ultrasonic wave signals towards the first receiving element. The first analog-to-digital converter is electrically connected with the first receiving element and the processor for converting the first ultrasonic wave signals into first digital signals and outputting the first digital signals to the processor. The processor reads the first digital signals and compares the first digital signals with the first critical value.

A method for evaluating stacking or sorting integrity at an output device of a high-speed apparatus that processes media includes: acquiring an audio data substantially in real-time from the output device of the high-speed apparatus while the high-speed apparatus is in operation, by use of an audio sensor located at the output device; transforming by a processor, the audio data to into a stacking or sorting integrity value; and if the stacking or sorting integrity value exceeds a predetermined threshold, stopping by the processor a document transport of the high-speed apparatus. An apparatus for evaluating stacking or sorting integrity at an output device, and a system for evaluating stacking or sorting integrity at an output device of a high-speed apparatus are also described.

A method for evaluating stacking or sorting integrity at an output device of a high-speed apparatus that processes media includes: acquiring an audio data substantially in real-time from the output device of the high-speed apparatus while the high-speed apparatus is in operation, by use of an audio sensor located at the output device; transforming by a processor, the audio data to into a stacking or sorting integrity value; and if the stacking or sorting integrity value exceeds a predetermined threshold, stopping by the processor a document transport of the high-speed apparatus. An apparatus for evaluating stacking or sorting integrity at an output device, and a system for evaluating stacking or sorting integrity at an output device of a high-speed apparatus are also described.

A medium conveyance apparatus includes a drive signal output circuit to output a drive signal at a predetermined timing, a first sound wave emitter to output a sound wave based on the drive signal outputted at the predetermined timing, a first sound wave receiver to output a first sound wave signal corresponding to the received sound wave, a second sound wave emitter to output a sound wave based on the drive signal outputted at the predetermined timing, a second sound wave receiver to output a second sound wave signal corresponding to the received sound wave, a processor to determine a state of the medium based on the first sound wave signal and the second sound wave signal, and an output circuit to output the first sound wave signal and the second sound wave signal to the processor at timings different from each other.

A sheet feeder, which is included in an image forming apparatus, includes a sheet loader on which a sheet is loaded, a sheet feeding body to feed the sheet from the sheet loader, and a sheet separator disposed to contact the sheet feeding body. The sheet is fed at a first average sheet feeding speed at which the sheet feeding body is in contact with the sheet separator without holding the sheet with the sheet separator. The sheet is fed at a second average sheet feeding speed at which the sheet feeding body is holding the sheet with the sheet separator. The first average sheet feeding speed is set smaller than the second average sheet feeding speed.

A system and method of detecting the presence of metallic objects in media to be conveyed in a medium transport system is disclosed. One or more metal detectors are included in the medium transport system to detect the presence of metal in the medium being transported. Signals from the metal detectors are sent to a system processor, which analyzes the signals, and produces proximity, duration, and/or intensity values therefrom. One or more microphones may also be included which detect the sound created as the medium is being transported. The processor computes sound values from the microphone signals, and analyzes the computed sound values along with the proximity, duration, and/or intensity values in order determine if the conveyance of the medium along the transport path should be stopped due to the presence of metal in the media or a jam occurring within the medium transport path.

A system and method of detecting the presence of metallic objects in media to be conveyed in a medium transport system is disclosed. One or more metal detectors are included in the medium transport system to detect the presence of metal in the medium being transported. Signals from the metal detectors are sent to a system processor, which analyzes the signals, and produces proximity, duration, and/or intensity values therefrom. One or more microphones may also be included which detect the sound created as the medium is being transported. The processor computes sound values from the microphone signals, and analyzes the computed sound values along with the proximity, duration, and/or intensity values in order determine if the conveyance of the medium along the transport path should be stopped due to the presence of metal in the media or a jam occurring within the medium transport path.

A system and method of detecting the presence of metallic objects in media to be conveyed in a medium transport system is disclosed. One or more metal detectors are included in the medium transport system to detect the presence of metal in the medium being transported. Signals from the metal detectors are sent to a system processor, which analyzes the signals, and produces proximity, duration, and/or intensity values therefrom. One or more microphones may also be included which detect the sound created as the medium is being transported. The processor computes sound values from the microphone signals, and analyzes the computed sound values along with the proximity, duration, and/or intensity values in order determine if the conveyance of the medium along the transport path should be stopped due to the presence of metal in the media or a jam occurring within the medium transport path.

A sheet transfer guide, which is disposed along a sheet conveyance passage through which a sheet passes, provided to guide the sheet, and is included in an image forming apparatus and an image reading device, includes a base material, a coat layer formed on the base material and having a surface roughness smaller than a surface roughness of the base material, and a guide face to which the sheet contacts. The coat layer is formed on the guide face.