JPS5853874B2 - Atsuden on Kansoshio Mochiita Kenshiyutsuhouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the presence of a receiver-transmitter having a conversion element, and applies vibrational energy to the receiver-transmitter within a field formed by vibration waves such as acoustic waves or electromagnetic waves. - The transmitter converts the given energy into energy in a completely different form and sends it out, and detects this to detect the presence of the receiver-transmitter. This is a detection method that can be applied to cases where a specific object is identified and detected by being attached to the object.

Conventionally, various types of devices have been developed in this category, such as devices that detect the presence of a resonator as the most primitive method, devices that use magnetism, and devices that combine a diode and an antenna and utilize the harmonics generated by them. There is a device.

A detector that uses the absorption effect of electromagnetic waves by a resonator detects changes in analog quantities due to the presence of this resonator, so the greater the distance, the less the difference, and the fact that there are many malfunctions is inevitable. do not have.

Moreover, other similar resonators exist everywhere, so they cannot be used for some purposes.

It is well known that these shattered resonators are influenced by the human body as a body effect, and are subject to changes in the Q and resonance frequency of the resonator, making it difficult to use them near the human body or metal objects.

Almost all devices using magnetism use perturbation or direct detection of magnetism, and since they detect changes in the magnetic field or the magnetic field, there is a high possibility of malfunction due to similar products, and there is a risk of detecting magnetic objects. When made small, there are various drawbacks such as small disturbance or difficulty in detecting it.

In this case, it is generally desirable for the receiver and transmitter installed in the subject to be small in terms of usage conditions, but on the other hand, this miniaturization reduces changes in the magnetic field, etc., making detection difficult. issues must also be addressed.

In addition, a detection device that combines a diode and an antenna is
The accuracy is theoretically higher than that of the detection device described above.

Since the above-mentioned disturbance-based device detects changes in analog quantities, it is difficult to rely on it with nearly 100% accuracy.

On the other hand, when determining a change in digital quantity, ie, 0 or l, accuracy is further increased and malfunctions are reduced.

Since the device that combines a diode and an antenna uses the generation of harmonics, it can detect using a digital method (0 or 1), which is why it is highly accurate.

However, this device uses microwaves,
Therefore, if a tag made up of a diode and an antenna is close to a metal body or a human body, the impedance of the antenna will be approximately O, making it impossible to transmit or receive microwaves.

Methods using broken microwave radio waves may cause problems due to volatility.

The receiver-transmitter presence detection method of the present invention reliably detects the presence of a receiver-transmitter without causing interference or interference because the radiated energy and the energy received via the receiver-transmitter are completely different. There are some features that can be used.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, G is an oscillator which oscillates an electric signal, which is converted into sound pressure by a converter T, and a sound wave S is emitted.

This sound pressure signal S is propagated to a receiver-transmitter C having an electric circuit including a piezoelectric vibrator (sound sensing element or piezoelectric element) B,
The piezoelectric vibrator B converts it into an electrical signal.

In this case, the electric signal E is converted to the same frequency or harmonic frequency and is received by the detection antenna R.

Contrary to this method, the electric signal E is used! 1 space, the receiver-transmitter C receives the electric signal, converts it into a sound wave S by the piezoelectric vibrator B, radiates it, receives it by the sound wave receiver TR, and converts it into an electric signal, A detection method can also be used.

By amplifying this signal with the amplifier A and displaying it on the display device IN, it is possible to determine whether there is a conversion circuit on the way or not.

FIG. 2 shows a combination of a piezoelectric vibrator B and a diode D, and the energy supplied to this circuit is also a sound pressure S or an electric signal E.

In the case of this sound pressure signal S, a current (2) converted into an electric signal flows through a diode D, and harmonics are generated due to the nonlinearity of this diode.

Therefore, it can operate satisfactorily even if the power of the supplied signal is not large.

This harmonic current excites the piezoelectric vibrator B again, and emits a harmonic electric signal E.

When non-linear elements are included, beats can be taken using multiple signals.

This is not limited to FIG. 2, but can be used commonly in the systems of the present invention.

This electrical signal E is received by the receiving device R, this electrical signal is amplified by the amplifier A, and the presence or absence of an intermediate circuit can be known by detecting and displaying the signal on the display device IN.

In this case, by configuring the piezoelectric vibrator B used in the receiver-transmitter C (bill) with a semiconductor, the diode D can also be configured together.

This method is possible with conventional technology such as IC, and is a good method for forming the device in a small size.

The same applies to the case shown in FIG. 1 above, but it is difficult to tune the circuit in order to obtain the maximum signal.

When using crystals, etc., take into account the capacity of the crystal, and do this if additional capacity is needed.

When using magnetic vibration elements or mechanical vibration elements,
The L of the coil must be taken into account.

Also, contrary to the above case, an electric signal E is sent to the receiver/transmitter C.
Alternatively, the signal may be received by a piezoelectric vibrator B and a diode D, converted into a harmonic sound wave S and emitted, received by a receiving device R, converted into an electrical signal, and detected.

In general, it is desirable to use frequencies other than audio frequencies for the sound pressure signal, and there are cases where frequencies below the audio frequency are used, cases where ultrasonic waves, etc. are used. Sound waves are preferable.

In terms of simply supplying energy, it is heavier to use a signal lower than the audio frequency, and lower frequencies have more penetrating power, making it possible to detect receivers and transmitters hidden inside.

Therefore, the use of this frequency varies depending on the purpose, object, etc.

As a method of concentrating energy, radiation directivity can be sharpened by using a parabola or an elliptical reflective surface array arrangement.

Figures 3 and 4 show a receiver/transmitter (tag) C attached to a product H using this piezoelectric vibrator at a store, etc., and when it is not picked up, that is, payment is not made, a bell rings and a stop light P. This is an example of a flashing alarm device used as a device to prevent shoplifting.

The antenna can be mounted on the side of the doorway or on the ceiling.

When using a directional antenna with sharp directivity, spots can also be detected.

FIG. 5 shows a case in which a receiver-transmitter C is attached to products K having the same appearance flowing on a conveyor J, and the products are automatically sorted.

It can also be applied to automatic detection of outsiders.

Transmitting and receiving converters (antennas) may be shared in some cases.

1. Different receiver-transmitters can be made by constructing circuits with different resonance frequencies in the receiver-transmitter C, or by using sound-sensing elements that exhibit different sensitivities.

The detection method of the present invention using the above-mentioned authoritative receiver-transmitter is different from the detection method using a resonant element or the detection method using a magnetic device, which simply displays a change in an analog quantity, and generates a signal that did not exist at all. It has the same high accuracy as the diode method for detecting digital quantities, and it also has features that are far superior to the diode method, and its application range is extremely wide, so its future practical effects are immeasurable.

According to the present invention, the receiver-transmitter converts the energy received in the field into a completely different form of energy and transmits it, so no interference or interference occurs and the presence of the receiver-transmitter is reliably detected. can be detected.

[Brief explanation of drawings]

FIGS. 1 and 2 are block diagrams for explaining different specific examples of the detection method according to the present invention, and FIGS. 3 to 5 are diagrams for explaining its application. S...Sound wave, A...Amplifier, E...Electromagnetic wave, IN
... Display device, B... Piezoelectric sound sensing element, D... Diode, C... Receiver-transmitter, G... Oscillator, H, K
...Product, T...Conversion device, P...Light, R.
...Detection antenna, J...Conveyor, TR...
Receiving device.

Claims (1)

[Claims] 1. A means for transmitting vibrational energy of sound waves, electromagnetic waves, or alternating magnetic fields to form a field of energy, and a means for receiving this energy while positioned within this field and converting it into a form of energy different from the received energy. 1. A system for detecting the presence of a receiver-transmitter, comprising a receiver-transmitter that transmits energy in different forms, and a detection means that receives the different forms of energy transmitted by the receiver-transmitter.