JPH0257065U

JPH0257065U -

Info

Publication number: JPH0257065U
Application number: JP11102688U
Authority: JP
Priority date: 1988-06-30
Filing date: 1988-08-24
Publication date: 1990-04-25

Description

[Brief explanation of drawings]

第１図はこの考案の第１の実施例を示す回転速
度検出装置のブロツク図、第２図は同実施例の動
作を示す波形図、第３図は第１の実施例における
ギヤツプ長に対する発振回路の出力電圧の平滑値
を示すグラフ、第４図はこの考案の第２の実施例
を示す回転速度検出装置の回路図、第５図は第２
の実施例におけるギヤツプ長さに対する発振回路
の出力電圧の平滑値を示すグラフ、第６図は従来
の回転速度検出装置を示す概略構成図、第７図は
従来の他の回転速度検出装置を示す概略構成図で
ある。１，９，１３……歯車、５，７，１４……電磁
コイル、６，１２……コルピツツ発振回路、Ｒ１
，Ｒ８……抵抗器（平滑化回路）、Ｃ１，Ｃ５…
…コンデンサ（平滑化回路）、Ｒ２，Ｒ３，Ｒ１
１，Ｒ１２……抵抗器（分圧回路）、１０，１８
……ピークホールド回路（ホールド回路）、１１
，１９……比較器、Ｒａ……抵抗器、Ｃａ……コ
ンデンサ、Ｌａ……電磁コイル。 Fig. 1 is a block diagram of a rotation speed detection device showing a first embodiment of this invention, Fig. 2 is a waveform diagram showing the operation of the same embodiment, and Fig. 3 is an oscillation with respect to gap length in the first embodiment. A graph showing the smoothed value of the output voltage of the circuit, FIG. 4 is a circuit diagram of a rotation speed detection device showing a second embodiment of this invention, and FIG.
A graph showing the smoothed value of the output voltage of the oscillation circuit with respect to the gap length in the embodiment of FIG. 6 is a schematic configuration diagram showing a conventional rotation speed detection device, and FIG. 7 shows another conventional rotation speed detection device. It is a schematic configuration diagram. 1, 9, 13... Gear, 5, 7, 14... Electromagnetic coil, 6, 12... Colpitts oscillation circuit, R1
, R8...Resistor (smoothing circuit), C1, C5...
...Capacitor (smoothing circuit), R2, R3, R1
1, R12...Resistor (voltage divider circuit), 10, 18
...Peak hold circuit (hold circuit), 11
, 19... Comparator, Ra... Resistor, Ca... Capacitor, La... Electromagnetic coil.

Claims

[Claims for Utility Model Registration] (1) A gear directly connected to a rotating body, an electromagnetic coil disposed opposite to the gear, and an oscillation circuit in which the inductance of the electromagnetic coil is a factor determining the oscillation frequency; A smoothing circuit that obtains a detection signal by smoothing the output signal of the oscillation circuit, a voltage dividing circuit that divides the voltage of the detection signal, and a hold circuit that holds the maximum value of the divided voltage value obtained by the voltage dividing circuit. and a pulse generating circuit that compares the value of the detection signal with the output value of the hold circuit and generates a pulse according to the rotational speed of the rotating body. . (2) A gear directly connected to a rotating body, an electromagnetic coil installed opposite to the gear, an oscillation circuit whose oscillation frequency is determined by the inductance of the electromagnetic coil, and smoothing of the output signal of the oscillation circuit. a smoothing circuit that obtains a detection signal by the smoothing circuit; a hold circuit that holds the maximum and minimum values of the detection signal obtained by the smoothing circuit; and an average of the maximum and minimum values of the held detection signal. A rotational speed detection device comprising: an averaging circuit that outputs a value; and a pulse generating circuit that generates the pulse by comparing the value of the detection signal with the output value of the averaging circuit. . (3) A gear directly connected to a rotating body, an electromagnetic coil installed opposite to the gear, an oscillation circuit whose oscillation frequency is determined by the inductance of the electromagnetic coil, and smoothing of the output signal of the oscillation circuit. a smoothing circuit that obtains a detection signal, a hold circuit that holds the minimum value of the detection signal obtained by the smoothing circuit, a booster circuit that boosts the output value of the hold circuit, and a voltage of the detection signal. A rotational speed detection device comprising: a pulse generation circuit that compares a level with an output value of the booster circuit and generates a pulse corresponding to the rotational speed of the rotating body. (4) A gear directly connected to a rotating body, an electromagnetic coil installed opposite to the gear, an oscillation circuit whose oscillation frequency is determined by the inductance of the electromagnetic coil, and smoothing of the output signal of the oscillation circuit. a smoothing circuit that obtains a detection signal by the smoothing circuit, a hold circuit that holds the maximum value of the detection signal obtained by the smoothing circuit, a voltage dividing circuit that divides the output value of the hold circuit, and the smoothing circuit. and a pulse generation circuit that compares the value of the detection signal obtained by the voltage dividing circuit with the partial pressure value obtained by the voltage dividing circuit and generates a pulse corresponding to the rotational speed of the rotating body. Characteristic rotation speed detection device. (5) Claim 1, characterized in that the electromagnetic coil and the oscillation circuit are connected via an electric wire.
5. The rotational speed detection device according to 2, 3 or 4. (6) The rotational speed detection device according to claim 5, further comprising a resistor inserted in series with the electromagnetic coil between the oscillation circuit and the electric wire. (7) The rotational speed detection device according to claim 5, further comprising a capacitor inserted between the oscillation circuit and the electric wire in parallel with the electromagnetic coil. (8) The rotational speed detection device according to claim 5, further comprising an electromagnetic coil inserted between the oscillation circuit and the electric wire in parallel with the electromagnetic coil.