JPH0415006U

JPH0415006U -

Info

Publication number: JPH0415006U
Application number: JP5606990U
Authority: JP
Priority date: 1990-05-28
Filing date: 1990-05-28
Publication date: 1992-02-06

Description

[Brief explanation of the drawing]

第１図はこの考案の一実施例による静電容量式
枚数検出装置のブロツク図、第２図は第１図の静
電容量−電圧変換回路６の詳細を示す回路図、第
３図は第１図のピークホールド回路１６の詳細を
示す回路図、第４図は第１図の静電容量式枚数検
出装置の動作を示すタイミングチヤート、第５図
は従来の静電容量式枚数検出装置を示すブロツク
図、第６図は第５図に示す静電容量式枚数検出装
置の動作を示すためのタイイングチヤート、第７
図は紙１０のずれた状態を示す図、第８図は従来
の装置において、第７図のような紙１０を検出し
た場合の出力を示す図である。２……電極、６……静電容量−電圧変換回路、
８……比較回路、１６……ピークホールド回路、
２０……電圧比較回路。 FIG. 1 is a block diagram of a capacitive sheet number detection device according to an embodiment of this invention, FIG. 2 is a circuit diagram showing details of the capacitance-voltage conversion circuit 6 of FIG. 1, and FIG. 1 is a circuit diagram showing details of the peak hold circuit 16, FIG. 4 is a timing chart showing the operation of the capacitive sheet number detecting device shown in FIG. 1, and FIG. 5 is a circuit diagram showing the operation of the capacitive sheet number detecting device of FIG. FIG. 6 is a tying chart showing the operation of the capacitive sheet number detection device shown in FIG. 5, and FIG.
The figure shows a state in which the paper 10 is shifted, and FIG. 8 is a diagram showing the output when the paper 10 as shown in FIG. 7 is detected in a conventional apparatus. 2... Electrode, 6... Capacitance-voltage conversion circuit,
8... Comparison circuit, 16... Peak hold circuit,
20...Voltage comparison circuit.

Claims

[Claims for Utility Model Registration] A pair of electrodes arranged to face each other with a detection target in between, a capacitance-to-voltage conversion circuit that changes output voltage according to changes in capacitance between the electrodes, and electrostatic capacitance. A capacitive sheet number detection device comprising: a determination circuit that determines whether a predetermined number of sheets are to be detected based on the output voltage of the capacitance-voltage conversion circuit, the determination circuit comprising: a capacitance-voltage conversion circuit; a peak holding circuit that holds the peak value of the output voltage of the circuit; outputting a first output value if the output voltage of the capacitance-voltage conversion circuit does not exceed a predetermined minimum fluctuation value;
A predetermined minimum variation detection circuit that outputs a second output value if the peak holding circuit exceeds the reference value; a comparison circuit that compares the output of the peak holding circuit with a reference value; When the output value changes to the second output value, the peak holding circuit is reset, and the output of the predetermined minimum fluctuation detection circuit changes to the second output value.
A capacitive sheet number detecting device, characterized in that when the output value changes from the output value to the first output value, the output of the comparison circuit is taken out as a detection output.