JPS5922188B2 - active sensing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for sensing external mechanical forces or objects.

Conventionally, in sensing devices, so-called sensors, mechanical sensors such as limit switches are small and inexpensive, but the sensing method is extremely passive, and electrical sensors such as infrared sensors and ultrasonic sensors are active. However, it has the disadvantage that the device is large and difficult to reduce in price.

In addition, both methods have the disadvantage that it is difficult to detect sensory characteristics such as texture.

An object of the present invention is to eliminate the above-mentioned drawbacks and to provide a small-sized sensing device that can perform active sensing using a mechanical method and, at the same time, can also perform sensory detection using discrimination using an electric circuit.

Embodiments of the present invention will be described in detail below based on the drawings.

In FIG. 1, a three-phase AC motor 3 and an AC generator 5 are fixed so as to share a rotating shaft 4.

Further, a detection member 1 made of a springy wire is fixed to the end of the rotating shaft 4 via a coupling member 2. The three-phase AC motor 3 is driven by a three-phase AC circuit 6, and its rotational frequency fd can be freely changed by a capacitor and a resistor that determine the time constant of the circuit. Further, the output voltage of the alternating current generator 5 is detected by a discrimination circuit 8, and a switching transistor can provide a switching signal according to an arbitrary voltage setting to an external output terminal 9.

Further, the power supply section 7 serves as a power source for the three-phase alternating current generating circuit 6 and the discrimination circuit 8. In this embodiment, a 6V battery is used as the power source T, and the three-phase AC generating circuit 6 gives a rotation of fd, 20H2 to the three-phase AC motor 3 to drive the AC generator 5 on the same axis. According to
An AC voltage E1 of 120 mV could be obtained.

Figure 2 shows this three-phase AC generating circuit. In this three-phase AC generating circuit, by configuring a three-stage closed loop of phase shifters having a phase shift of 1200 at the center frequency, the loop becomes a positive feedback loop, and a sine wave can be obtained by adjusting the gain.

The shift between the phase shifters of the sine wave maintains a relationship of 1200 and is 3
A phase current is obtained. Further, by adjusting the time constants Rp and Cp in FIG. 2, the rotational frequency fd can be arbitrarily set. The output of the alternator is input to a discrimination circuit 8.

FIG. 3 shows a block diagram of this discrimination circuit.
In other words, this is a generally well-known voltage discrimination circuit, and the third
By setting the comparison reference voltage of the comparator of the voltage detection comparison circuit shown in the figure, any threshold voltage Eth. It becomes possible to determine the

In FIG. 4, the rotation status of the detection member 1, the three-phase AC motor 3, and the AC generator 5, and the rotation status of the AC generator 5 are shown.
The AC waveform 10 from FIG.

In this apparatus in the above state, when an object to be detected comes into contact with the detection member 1, the rotation of the rotation shaft 4 is hindered due to the contact resistance with the detection member 1 made of a springy wire, and the rotation speed is reduced. The voltage decreases or the rotation stops, and the alternating current voltage of the alternator 5 on the same axis decreases. FIG. 5 shows a situation when the detection member 1 of the present device comes into contact with the object to be detected 11 and an example 12 of the AC waveform from the AC generator 5.

In this embodiment, the object to be detected 11 is
An alternating current voltage E2 of 0 to 45 mV could be obtained by contacting the electrode. As explained above, from 120 mV of the AC voltage E1 of the alternator 5, E2O ~ 45 m
V to the threshold voltage Eth.V of the discrimination circuit 8. 85
It was easily distinguishable by setting m.

In this embodiment having the above-described configuration, the detection member 1 was able to rotate and come into contact with the object 11 to be detected, thereby achieving good switching characteristics.

The motor and generator used in this device are not limited to three-phase AC motors and alternating current generators; other types of motors,
It can also be used with a generator.

Furthermore, the motor and generator, which are coaxially fixed, can be housed in the same housing. The discrimination circuit is not limited to a voltage discrimination circuit, and other discrimination circuits such as a waveform discrimination circuit can also be used.

In this device configured as described above, the detection range can be expanded by actively rotating the detection member, which was not possible in conventional mechanical sensing devices.

Furthermore, by variously changing the setting conditions of the discrimination circuit, it becomes possible to detect minute analog quantities that could not be detected by conventional sensing devices. As described above in detail, this device is capable of detecting cancers that have previously been diagnosed in humans. It is highly effective as a sensor for sensory tests such as texture, wind feel, etc., and its range of applications is extremely wide.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of the present invention. Figure 2 shows a three-phase AC generating circuit. Figure 3 is a block diagram of the discrimination circuit. FIGS. 4 and 4a are diagrams showing a state in which the apparatus of the present invention is not in contact with an object to be detected. 4b is a diagram showing the AC waveform from the AC generator at that time. FIGS. 5 and 5a are diagrams showing the situation when the device of the present invention comes into contact with an object to be detected. 5b is a diagram showing an example of the AC waveform from the AC generator at that time. 1...detection member, 2...coupling member, 3
...3-phase AC motor, 4 ... Rotating shaft,
5... AC generator, 6... 3-phase AC generating circuit, 7... Power supply section, 8... Discrimination circuit, 9... - External output terminal, 10... AC waveform, 11... Object to be detected, 12... AC waveform example.

Claims (1)

[Claims] 1. A detection member made of a springy wire, a motor for rotating this detection member at a predetermined frequency, a generator for detecting the rotation of this motor, and an AC waveform obtained from this generator. 1. An active sensing device comprising a discrimination circuit for discriminating in an analog manner the resistance between the detection member and an object touching the detection member based on the detection member.