JPS6239327Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a device that converts the rotational speed of a rotating shaft into an electric voltage signal and detects excessive acceleration and deceleration of the rotating shaft.

(Prior art and problems) Conventionally, devices for detecting excessive acceleration/deceleration of a rotating shaft using electrical signals have been either converting the rotation signal into a pulse signal and detecting it with a pulse counter, or converting the rotation signal into a voltage signal and detecting it on the acceleration side. Separate electric differential circuits were installed on the and deceleration sides for detection.

On the other hand, the power supply voltage fluctuation detection circuit shown in Japanese Patent Application Laid-open No. 48-32568 can be used as the device for detecting excessive acceleration/deceleration of a rotating shaft, which is the object of the present invention. As such, a differential capacitor and differential amplification circuit are required.

Therefore, all of the conventional detection techniques have the drawbacks of complicated circuit configurations and high production costs.

(Purpose of the invention) The present invention was devised to eliminate the drawbacks of the prior art described above, and eliminates the need for converting the rotational speed into pulses, and also eliminates the need for two sets of differentiating circuits and differential amplification circuits. The object of the present invention is to provide a detection device with a simple circuit configuration.

(Structure of the invention) The invention consists of an alternator driven by a rotating shaft,
A rectifier circuit and a DC filter circuit that rectify the current generated by the AC generator, a bridge circuit that is connected to the output end of the DC filter circuit and has a capacitor connected in parallel to resistors on two opposing sides, and the bridge circuit. It is characterized by consisting of two rectifiers connected in series with opposite conduction directions, and a branch output terminal formed at the series connection point of the two rectifiers.

(Example) Embodiments of the present invention will be described with reference to the drawings.

The figure shows a block diagram of the electric circuit of the present invention, in which 1 is an alternating current generator directly connected to the rotating shaft, 2 is a rectifier circuit, 3 is a DC filter circuit, 4 is a bridge circuit, and 5 is a rectifier circuit.
is a resistor, 6 is a capacitor, 7 and 8 are rectifiers, 9 is an acceleration detection terminal, and 10 is a deceleration detection terminal. As shown in the figure, the AC voltage output of an AC generator 1 directly connected to a rotating shaft is converted into a DC voltage output by a rectifier circuit 2. The AC component contained in the DC voltage output is removed by a DC filter circuit 3 and supplied to a bridge circuit 4. Of the two opposing sides of the bridge circuit 4, one set has only the resistor 5, and the other set has only the resistor 5.
and capacitor 6 are connected in parallel, so if the rotational speed of the rotating shaft remains unchanged or changes very slowly, the rate of change over time of the DC voltage supplied from the DC filter circuit 3 will be completely absent, or Since the time constant is very slow compared to the time constant determined by the resistor 5 and capacitor 6, the charging/discharging effect of the capacitor 6 does not appear, and the output of the bridge circuit 4 is zero because the resistance values of the four resistors 5 are equal. Or a value close to zero.

Next, if the rotation speed of the rotating shaft changes suddenly,
Since the time rate of change of the DC voltage supplied from the DC filter circuit 3 is close to the time constant determined by the resistor 5 and the capacitor 6, or is very fast, the charging and discharging effect of the capacitor 6 appears prominently, and the bridge circuit 4 The voltage balance is disrupted, and DC output is supplied to output sides A and B. In the case of excessive acceleration, a charging current flows through the capacitor 6, so that a signal is obtained from the acceleration detection terminal 9 in the circuit consisting of the terminal A, the acceleration detection terminal 9, the rectifier 8, and the terminal B. in this case,
Since the deceleration output terminal 10 is short-circuited by the rectifier 8, the output signal is zero.

In the case of excessive deceleration, a discharge current flows from the capacitor 6, so a circuit consisting of terminal B, deceleration output terminal 10, rectifier 7, and terminal A connects the deceleration output terminal 1 to the deceleration output terminal 1.
A signal is obtained from 0. In this case as well, the acceleration output terminal 9 is short-circuited by the rectifier 7, so
The output signal is zero.

Note that the rectifiers 7 and 8 use diodes in this embodiment.

(Effects) Since rotational motion is directly input to the alternator and the rotational speed is converted into an electrical signal, and a bridge circuit is used, mechanisms such as pulse conversion, differentiation circuits, differential amplification circuits, etc. are not required, making it easy to operate. Acceleration or deceleration can be detected with the same circuit, and production costs can be reduced.

[Brief explanation of the drawing]

The figure shows an electrical circuit diagram of an embodiment of the invention. 1... AC generator directly connected to the rotating shaft, 2... Rectifier circuit, 3... DC filter circuit, 4... Bridge circuit, 5... Resistor, 6... Capacitor, 7...
Rectifier (diode) that bypasses the deceleration signal,
8... Rectifier (diode) that bypasses the acceleration signal.

Claims (1)

[Claims for Utility Model Registration] (1) An alternating current generator driven by a rotating shaft, a rectifier circuit and a direct current filtering circuit for rectifying the current generated by the alternating current generator, and an alternating current generator connected to the output end of the direct current filtering circuit. , a bridge circuit in which capacitors are connected in parallel to resistors on two opposing sides, two rectifiers connected in series with opposite conduction directions connected to the output end of the bridge circuit, and the two rectifiers connected in series. An excessive acceleration/deceleration detection device for a rotating shaft, comprising a branch output terminal formed at a connection point. (2) The excessive acceleration/deceleration detection device for a rotating shaft according to claim (1), wherein the two rectifiers are diodes.