JP2013007960A5 - - Google Patents

Description

In order to achieve the above object, an image forming unit for forming an image on a recording material, and a recording material on which an image is formed by the image forming unit is conveyed in a first direction for discharging the image forming apparatus to the outside . or different sided conveying means for conveying in a second direction, said the preceding sheet is a recording material being conveyed earlier duplex conveyance is a recording material on which the image is formed with said first direction by said image forming means When the succeeding paper, which is the recording material transported next in the second direction by the means, is transported in the first direction by the double-sided transport means, the preceding paper and the succeeding paper pass each other. And a control means for controlling the timing.

In step S107, the CPU 201 determines the printing area of the recording material S1 and the printing area of the recording material S2 fed after the recording material S1. In S 1 08, the CPU 201 determines the timing of feeding the recording material S2. When determining in S106 that the recording material S1 is not subjected to double-sided printing, the recording material S2 is determined based on the length of the recording material S1 and the timing at which the space between the sheets when performing single-sided printing is secured. This is the timing for feeding the material S2. On the other hand, when it is determined in S106 that double-sided printing is performed on the recording material S1, the feeding timing of the recording material S2 differs depending on the printing area of the recording material S1 and the printing area of the recording material S2. This paper feed timing control method will be described in detail with reference to FIGS. When the feeding timing of the recording material S2 is determined in S108, the process proceeds to S102.

In view of such conditions, the sheet interval L of the recording material S1 and the recording material S2 are, L = Lmin + (LS1- L2) and that Do. Further, the sheet feeding timing of the recording material S2 can be determined from the sheet interval L and the above equation (1). However, the space L is L> = Lmin. If the recording material S1 needs to pass through the intermediate paper discharge roller 117 before the recording material S2 reaches the intermediate paper discharge roller 117, LJ + (LS1- (from the reverse position RP to the intermediate paper discharge roller 117). The longer distance)) and Lmin are compared, and the longer one is set as the sheet interval L.

Claims (6)

Image forming means for forming an image on a recording material;
The recording material on which the image is formed by the image forming means is conveyed in a first direction for discharging the recording material to the outside of the image forming apparatus , or the recording material on which the image is formed by the image forming means is the first direction. A double-sided conveying means for conveying in a different second direction ;
The preceding paper, which is the recording material that has been transported first , is transported in the second direction by the double-sided transport unit, and the subsequent sheet, which is the recording material that is transported next, is the first direction by the double-sided transport unit. an image forming apparatus comprising when being conveyed, to have a control means for controlling the timing of passing of the succeeding paper and the preceding paper.   The control means controls the timing of passing between the preceding sheet and the succeeding sheet based on the image area formed on the passing surface of the preceding sheet and the image area formed on the passing surface of the succeeding sheet. The image forming apparatus according to claim 1.   The control means includes a non-imaged area at the leading edge in the conveyance direction of the preceding paper and a non-imaged area at the trailing edge in the conveyance direction of the subsequent paper on the passing surfaces of the preceding paper and the subsequent paper. 3. The image forming apparatus according to claim 2, wherein the image forming apparatus controls the timing of passing between the preceding paper and the succeeding paper by determining that the area is a passable area.   The said control means controls the said passing timing so that the image formed in the passing surface of the said preceding paper and the said following paper may not overlap, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Image forming apparatus. 5. The double-sided conveyance means is a triple roller, and can carry out conveyance in the first direction and conveyance in the second direction at the same time. The image forming apparatus according to any one of the above. 6. The second direction according to claim 1, wherein the second direction is a direction in which the recording material is conveyed in order to form an image on the second surface of the recording material on which the image is formed on the first surface. The image forming apparatus according to claim 1.