JP2008158356A5 - - Google Patents

Claims (4)

帯電している被計測物と検知電極との間に、当該被計測物と検知電極間で発生する電界を所定の振動振幅で遮蔽するチョッパを配置し、当該チョッパによって前記電界を前記所定の振動振幅で遮蔽した時の検知電極で検出される検出出力を測定する第１の測定手段と、前記被計測物の真の表面電位を測定する第２の測定手段と、前記第１の測定手段で測定された検出出力と前記第２の測定手段で測定された表面電位とによって前記検知電極から被計測物の表面位置までの距離を計測する距離計測手段とを備え、前記第２の測定手段は、前記第１の測定手段の検出出力を前記第１の測定手段自体の電位にフィードバックして、被計測物表面と前記第１の測定手段の間の電位差を０に制御する制御手段を備え、当該０に制御されたときにおける前記第１の測定手段自体の電位を被計測物の表面電位とみなして出力する表面電位測定手段で構成されることを特徴とする距離センサ。 A chopper that shields the electric field generated between the object to be measured and the detection electrode with a predetermined vibration amplitude is disposed between the charged object to be measured and the detection electrode, and the electric field is generated by the chopper with the predetermined vibration. a second measurement means for measuring a first measuring means for measuring the detected output detected by the detection electrode when shielded by the amplitude, the true surface conductive position of the object to be measured, the first measurement and a distance measuring means for measuring a distance to the surface position of the object to be measured from the detection electrode by the measured surface potential at the measured and detected output means second measuring means, the second measurement The means feeds back the detection output of the first measuring means to the potential of the first measuring means itself to control the potential difference between the surface of the object to be measured and the first measuring means to zero. Before and when it is controlled to 0 Distance sensor, characterized in that consists of a surface potential measuring unit for the first potential measurement means itself outputs regarded as the surface potential of the object to be measured. 請求項１記載の距離センサにおいて、
前記第１の測定手段は、前記チョッパの振動時の温度を計測する温度センサを備えていることを特徴とする距離センサ。 The distance sensor according to claim 1, wherein
The distance sensor according to claim 1, wherein the first measuring means includes a temperature sensor for measuring a temperature when the chopper vibrates . 画像の静電潜像を担持する感光体と、当該静電潜像をトナーによって可視化像に現像する現像装置と、当該感光体のトナー可視化像を感光体から転写され、転写されたトナー可視化像を記録媒体に転写する中間転写体と、記録媒体に転写されたトナー可視化像を定着する加熱定着部材とを備えた画像形成装置において、
前記感光体、中間転写体及び加熱定着部材のいずれかを被計測物とし、当該被計測物に請求項１または２記載の距離センサを配置し、当該被計測物表面の電位及び前記検知電極から被計測物の表面位置までの距離を監視することを特徴とする画像形成装置。 A photoreceptor carrying an electrostatic latent image of the image, a developing device for developing the electrostatic latent image into a visualized image with toner, and a toner visualized image transferred from the toner visualized image of the photoreceptor and transferred. In an image forming apparatus comprising: an intermediate transfer member that transfers a toner image to a recording medium; and a heat fixing member that fixes a toner visualized image transferred to the recording medium .
Any one of the photosensitive member, the intermediate transfer member, and the heat fixing member is used as an object to be measured, and the distance sensor according to claim 1 or 2 is disposed on the object to be measured, and the potential of the surface of the object to be measured and the detection electrode An image forming apparatus for monitoring a distance to a surface position of an object to be measured . 請求項３記載の画像形成装置において、
前記感光体は、回転する感光体ドラムであり、前記距離センサによって当該感光体ドラムの偏芯量と偏芯位相を検知することにより、感光体ドラムの偏芯による周期的位置ずれの振幅と位相を制御することを特徴とする画像形成装置。 The image forming apparatus according to claim 3 .
The photoconductor is a rotating photoconductor drum, and the distance sensor detects an eccentricity amount and an eccentric phase of the photoconductor drum, whereby an amplitude and a phase of periodic positional deviation due to the eccentricity of the photoconductor drum are detected. An image forming apparatus that controls the image forming apparatus.