Arrangement for diagnosing the cause of communication interruption
between two CPUS
    33.
    发明授权
    Arrangement for diagnosing the cause of communication interruption between two CPUS 失效
    用于诊断两个CPU之间的通信中断的原因的安排

    公开(公告)号:US5230043A

    公开(公告)日:1993-07-20

    申请号:US560832

    申请日:1990-07-31

    CPC分类号: G06F11/0757 G06F15/17

    摘要: An arrangement for communication between two CPUs which allows diagnosis of whether the cause of an interrupt in communication between the CPUs is due to a routine interrupt or a failure in the communication line. Timers generate overflow signals in the event that data from one or the other CPU is late in arriving. Lateness is determined by comparing the timer values to stored values in memory. Control units respond to the timers and switch the transmission level of the CPUs so that they pass a predetermined signal pattern between themselves, indicating that the interrupt is in effect but that communication lines are still open. When one of the CPUs fails to detect the confirmation signal, the CPU causes a communication failure to be indicated.

    Transfer unit of an image forming apparatus
    34.
    发明授权
    Transfer unit of an image forming apparatus 失效
    图像形成装置的传送单元

    公开(公告)号:US5220387A

    公开(公告)日:1993-06-15

    申请号:US789647

    申请日:1991-11-08

    IPC分类号: G03G15/16

    CPC分类号: G03G15/1655

    摘要: A transfer unit of an image forming apparatus includes a transfer device, a pressing member, and a regulative member. The transfer device is provided adjacent to a photoconductor of the image forming apparatus and is separable from the photoconductor under its own weight. The pressing member presses the transfer device against the photoconductor. The regulative member regulates the distance by which transfer device is separated from the photoconductor when the pressing member disengages the transfer device therefrom. In this transfer unit, if a printing sheet is large, the pressing member disengages the transfer device after a given transfer operation. As a result, the transfer device separates from the photoconductor under its own weight, with the distance separating the transfer device from the photoconductor being regulated by the regulative member. Then, the transfer device idles in the separated state, wherein preparation for a subsequent transfer operation is made. In this manner, the transfer device is idled simply by regulating the movement of the transfer device through means of the regulative member. Consequently, little distortion occurs to the transfer unit support frames, and deterioration of the quality of the transferred images is thus checked.