Abstract: An apparatus, which has a second memory for storing data and which calls for the stored data from the second memory so as to output the data, is provided with an inputted-time storing means for storing in the means the times at which respective data were stored, a timer for counting time, a compression processing section, and a compressed-time measuring section for storing the times at which the compression processing section carried out its compressing operations. In accordance with information from the inputted-time storing means, the timer and the compressed-time measuring section, the compression processing section detects data whose compressing times have been due from the data stored the second memory, and carries out processes on the selected data in order to increase the remaining amount of the second memory. Thus, it becomes possible to maintain necessary data efficiently using the limited storage capacity of the second memory, without imposing a greater workload on the user.

Abstract: After placing an original document on a document platen of a copying apparatus main body, when a detection switch detects a predetermined angle of .theta. of a document cover in the course of closing the document cover, a light-emitting device of a distance-measuring sensor is driven. Light released from the light-emitting device is projected onto the original document or the document cover, and the reflected light is received by a light-receiving device. A signal corresponding to the light-receipt point of the light-receiving device is released, and a measurement is made to find the distance from the sensor to the original document or to the document cover based on the signal. A discrimination is made as to the presence or absence of original document based on the measured distance, and copying control suitable for the result of the discrimination is carried out.

Abstract: A document fed from a document loading tray is first transported into one branch transport path for invention of the transporting direction thereof, and then is guided through the other branch transport path and transported on to a document scanning area. In this process, when the trailing edge of the inverted document has passed the branching point between the two transport paths, the feeding of a succeeding document toward said one transport path is initiated. Also, when the trailing edge of the inverted preceding document has passed the branching point, the transportation of the preceding document is temporarily stopped, during which time the transporting direction of the succeeding document is inverted. This allows the succeeding document to be brought close to the preceding document. At this time also, the feeding of a further succeeding document may be initiated.

Abstract: A sensor (SEN6a) is provided for detecting a presence of a document sheet at a specified position during a transit path of document sheets supplied. According to detection output from this sensor (SEN6a), a continuous presence time of a document sheet is obtained, and if the continuous presence time obtained is longer than the continuous document presence time obtained last time, this is regarded as an indication of a multiple feed of document sheets, and the feeding of document sheets is stopped.