JP2017016060A5

JP2017016060A5 -

Info

Publication number: JP2017016060A5
Application number: JP2015135396A
Authority: JP
Filing date: 2015-07-06
Publication date: 2018-08-02
Anticipated expiration: 2035-07-06

Description

上述した課題を解決するために、本発明は、像担持体の表面にトナー像を形成するトナー像形成手段と、前記像担持体とニップ形成部材との当接による転写ニップに挟み込んだ記録シートに前記像担持体上のトナー像を転写するために、交流電圧に直流電圧を重畳した重畳電圧からなる転写バイアスを出力する転写電源と、前記転写電源からの出力を制御する制御手段とを備える画像形成装置において、環境を検知する環境検知手段と、前記像担持体から前記ニップ形成部材に転写されたトナー像のトナー付着量を検知するトナー付着量検知手段とを設け、前記環境検知手段による検知結果に基づいて、前記転写電源から出力される前記転写バイアスを、重畳電圧からなるものと、直流電圧だけからなるものとで切り替えるバイアス切替処理と、所定のタイミングで、直流電圧だけからなる前記転写バイアスを用いる条件、及び重畳電圧からなる前記転写バイアスを用いる条件のそれぞれで前記ニップ形成部材上にテストパターン像を転写し、それぞれのテストパターン像のトナー付着量を検知した結果に基づいて、直流用のトナー像形成条件、及び重畳用のトナー像形成条件を決定する条件決定処理を実施するように、前記制御手段を構成したことを特徴とするものである。 In order to solve the above-described problems, the present invention provides a recording sheet sandwiched between a toner image forming means for forming a toner image on the surface of an image carrier and a transfer nip formed by contact between the image carrier and a nip forming member. In order to transfer the toner image on the image carrier, a transfer power source that outputs a transfer bias composed of a superimposed voltage obtained by superimposing a DC voltage on an AC voltage, and a control unit that controls an output from the transfer power source are provided. In the image forming apparatus, an environment detection unit that detects an environment and a toner adhesion amount detection unit that detects a toner adhesion amount of a toner image transferred from the image carrier to the nip forming member are provided, and the environment detection unit Bias switching processing for switching the transfer bias output from the transfer power source between a superimposed voltage and a DC voltage only based on a detection result The test pattern image is transferred onto the nip forming member at a predetermined timing under the condition using the transfer bias consisting of only a DC voltage and the condition using the transfer bias consisting of a superimposed voltage. on the basis of the result of detecting the toner adhesion amount, preparative toner image forming condition of the DC, and to perform condition determination process for determining bets toner image forming conditions for superimposing, that constitutes the control means It is a feature.

Claims

A toner image forming means for forming a toner image on the surface of the image carrier, and a toner image on the image carrier on a recording sheet sandwiched in a transfer nip formed by contact between the image carrier and a nip forming member; In addition, in an image forming apparatus comprising: a transfer power source that outputs a transfer bias composed of a superimposed voltage obtained by superimposing a DC voltage on an AC voltage; and a control unit that controls an output from the transfer power source.
Environmental detection means for detecting the environment, and toner adhesion amount detection means for detecting the toner adhesion amount of the toner image transferred from the image carrier to the nip forming member,
Based on the detection result by the environment detection means, the bias switching process for switching the transfer bias output from the transfer power source between a superposed voltage and a DC voltage only, and DC at a predetermined timing A test pattern image was transferred onto the nip forming member under the condition using the transfer bias consisting of only the voltage and the condition using the transfer bias consisting of the superimposed voltage, and the toner adhesion amount of each test pattern image was detected. based on the results, to perform preparative toner image forming condition of the DC, and a condition determination process for determining bets toner image forming conditions for the superimposition, the image forming apparatus characterized by being configured the control unit.

The image forming apparatus according to claim 1.
Corresponding to the area between the preceding recording sheet and the succeeding recording sheet in the entire area in the surface movement direction of the nip forming member during the continuous image forming operation for continuously forming images on a plurality of recording sheets. A condition for temporarily changing the toner image forming condition by the toner image forming means based on a comparison between a result of detecting the toner adhesion amount and a predetermined reference value in a corresponding area between sheets to be formed. An image forming apparatus characterized in that the control means is configured to perform change processing.

The image forming apparatus according to claim 2.
When the transfer bias is switched by the bias switching process, the reference value changing process for changing the reference value used in the condition temporary changing process to a value corresponding to the transfer bias after the switching is performed. An image forming apparatus comprising a control means.

The image forming apparatus according to claim 3.
In the reference value changing process, the control means is adapted to adopt the one corresponding to the transfer bias after switching among the reference value for DC and the reference value for superimposition stored in advance. An image forming apparatus characterized by comprising.

The image forming apparatus according to claim 3.
In the reference value changing process, the control unit is configured to convert a reference value before switching the transfer bias into a reference value after switching the transfer bias using a conversion algorithm stored in advance. Image forming apparatus.

The image forming apparatus according to claim 4 or 5,
In the condition determination process, a test toner image is formed under the direct current toner image formation conditions and the toner adhesion amount is detected, and a test toner image is formed under the superposition toner image formation conditions. The reference value determination process for determining the DC reference value and the superimposition reference value in claim 4 or the conversion algorithm in claim 5 is performed based on the result of detecting the toner adhesion amount. An image forming apparatus comprising the control means.

The image forming apparatus according to claim 6, wherein
The predetermined timing is a timing at which an image forming operation based on a user command is not performed, or a timing before the driving of the toner image forming unit is stopped after an image based on a user command is formed. Image forming apparatus.

The image forming apparatus according to claim 7.
If the predetermined parameter correlated with the amount of change in the charge amount of the toner set in the toner image forming unit is less than or less than the predetermined threshold even at the predetermined timing, the condition determination process And the predetermined parameter exceeds a predetermined upper limit even during a continuous image forming operation in which images are continuously formed on a plurality of recording sheets that are not at the predetermined timing. In the image forming apparatus, the control unit is configured to temporarily interrupt a continuous image forming operation and execute the condition determining process when the above is reached.

9. The image forming apparatus according to claim 8, wherein
The predetermined parameter is an elapsed time from the previous execution of the condition determination process, an amount of change in the environment from the previous execution of the condition determination process, or an average image area ratio within the most recent predetermined period. An image forming apparatus characterized by a variation amount.

A toner image forming means for forming a toner image on the surface of the image carrier, and a toner image on the image carrier on a recording sheet sandwiched in a transfer nip formed by contact between the image carrier and a nip forming member; In addition, in an image forming apparatus comprising: a transfer power source that outputs a transfer bias composed of a superimposed voltage obtained by superimposing a DC voltage on an AC voltage; and a control unit that controls an output from the transfer power source.
Environmental detection means for detecting the environment, and toner adhesion amount detection means for detecting the toner adhesion amount of the toner image transferred from the image carrier to the nip forming member,
A bias switching process for switching the transfer bias output from the transfer power source between a bias voltage and a DC voltage based on a detection result by the environment detection unit; and a surface of the nip forming member A process of correcting the toner image forming condition of the toner image forming means based on a comparison between a result of detecting the toner adhesion amount of the halftone test toner image transferred to the toner and a predetermined reference value; Switching between a superimposing reference value used when the bias is set to a superposed voltage and a direct current reference value used when the transfer bias is set only to a DC voltage An image forming apparatus, wherein the control means is configured to perform processing.