HP Color 9850mfp Service Manual - Page 106

II UNIT EXPLANATION TRANSFER BELT UNIT 5.2 Operation hp Color 9850mfp 5.2.1 Transfer belt pressure/release mechanism The 1st transfer roller that presses the transfer belt against the drum is made up of the 1st transfer rollers Y, M and C for the drums Y, M and C and the 1st transfer roller K for the drum K. The three 1st transfer rollers Y, M and C operate as a unit (color 1st transfer roller assembly). When the 1st transfer is made from the drum to the transfer belt, the color 1st transfer roller assembly and the 1st transfer roller K push out the transfer belt from the inside and press it against the drum, by means of the cam that is driven by the 1st transfer pressure/release motor (M19). The form of pressure varies with the copy mode. In the full color mode, both of the color 1st transfer roller assembly and the 1st transfer roller K are pressed. However in the black-and-white mode, only the 1st transfer roller K is pressed. The release condition is detected by the 1st transfer HP sensor (PS15). The cam drive postion which varies with the copy mode is controlled by the drive amount of the M19 which starts when the PS15 turns off. [18] [8] [9] [10] [17] [16] [15] [11] [6] [7] [14] [5] [12] [4] [3] [2] [1] [13] [1] When totally released [2] When in the black-and-white mode [3] When in the full color mode [4] 1st transfer roller K pressure release arm [5] Drive coupling [6] 1st transfer roller K pressure release cam [7] 1st transfer roller C pressure release cam [8] Drum Y [9] Transfer belt [10] Drum M [11] Drum C [12] Drum K [13] 1st transfer roller K [14] 1st transfer roller C [15] 1st transfer pressure/release motor (M19) [16] Color 1st transfer roller assembly [17] 1st transfer roller M [18] 1st transfer roller Y 2-32