Grammage detection sensor for recording material and image forming apparatus

摘要

A grammage detection sensor according to an aspect of the present invention includes a transmission unit configured to transmit an ultrasonic wave, a reception unit configured to receive the ultrasonic wave transmitted from the transmission unit, and a control unit configured to detect a grammage of a recording material, when a plurality of recording materials are continuously conveyed between the transmission unit and the reception unit, on the basis of a first ultrasonic wave received by the reception unit after the ultrasonic wave is transmitted by the transmission unit between a preceding recording material and a recording material following the preceding recording material, and a second ultrasonic wave received via a recording material by the reception unit after the ultrasonic wave is transmitted by the transmission unit.

主权项

1. An ultrasonic wave sensor used in an image forming apparatus having an image forming unit for forming an image on a recording material and a control unit for controlling an image forming condition of the image forming unit when an image is formed on the recording material, comprising:
a transmission unit configured to transmit an ultrasonic wave; and a reception unit configured to receive the ultrasonic wave transmitted from the transmission unit, wherein the ultrasonic wave sensor outputs a first ultrasonic wave and a second ultrasonic wave to the control unit so that the control unit controls the image forming condition, the first ultrasonic wave being received by the reception unit not via the recording material after the ultrasonic wave is transmitted by the transmission unit, and the second ultrasonic wave being received by the reception unit via the recording material after the ultrasonic wave is transmitted by the transmission unit, wherein a plurality of recording materials including a first recording material and a second recording material following the first recording material are continuously conveyed between the transmission unit and the reception unit, wherein in a case where an interval between a trailing edge of the first recording material and a leading edge of the second recording material is longer than a predetermined threshold, the ultrasonic wave sensor outputs the first ultrasonic wave and the second ultrasonic wave to the control unit so that the control unit controls the image forming condition when an image is formed on the second recording material, the first ultrasonic wave being received by the reception unit between the first recording material and the second recording material, and the second ultrasonic wave being received by the reception unit via the second recording material, and in a case where the interval is shorter than the predetermined threshold, the ultrasonic wave sensor outputs the first ultrasonic wave and the second ultrasonic wave to the control unit so that the control unit controls the image forming condition when the image is formed on the second recording material, the first ultrasonic wave being received by the reception unit before the first recording material reaches between the transmission unit and the reception unit, and the second ultrasonic wave being received by the reception unit via the second recording material.