JP3051730B1 - Lost and Found System - Google Patents

Abstract

An object of the present invention is to provide a compact and inexpensive lost item prevention system that can prevent a portable item from being left behind. SOLUTION: A radio wave reflector which is attached to or attached to a portable article and operates using energy of a received radio wave as a power source,
A transmitter that radiates radio waves of a predetermined frequency into space, a receiver that receives a radio wave reflected by the radio wave reflector of the radio wave radiated from the transmitter, and an alarm that issues an alarm based on a signal transmitted from the receiver The transmitter driven by a battery, the receiver and the alarm are integrally configured, and a signal transmitted from the receiver is radiated from the transmitter and passes through the radio wave reflector. The signal is transmitted when the path of the radio wave returning to the receiver is interrupted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lost item prevention system for preventing a portable item from being left behind and lost.

[0002]

2. Description of the Related Art Conventionally, portable items such as umbrellas are often forgotten, and even if they are reported, these portable items are generally not very expensive, and the number of such items is enormous. It is rare to return to. A search system using GPS similar to a car navigator, or a transmitter attached to a target, and a radio wave from this transmitter is received to search for such portable items and wandering elderly people, or to investigate the ecology of birds. A method of specifying a distance and a direction from the intensity and the arrival direction of the object has been put to practical use.

[0003]

However, the above-mentioned method is problematic in that the apparatus becomes large and the price becomes expensive, so that it cannot be applied to a portable product or the like when the price of the product itself is not so expensive. was there. The present invention has been made under such a background, and a compact transceiver capable of preventing a portable item from being left behind by a small transceiver carried by a person and a radio wave reflector attached or attached to the portable item. It is an object of the present invention to provide an inexpensive lost item prevention system.

[0004]

According to the first aspect of the present invention, there is provided a transmitter for radiating a radio wave of a predetermined frequency to a space,
The energy of the received radio wave attached or attached to the product
And rectify the power to a power source,
Radio wave reflector for radiating a number of radio waves into space, and said radio wave reflector
A receiver that receives a radiated radio wave according to the present invention, and an alarm that issues an alarm by a signal transmitted from the receiver, the battery-driven transmitter, the receiver, and the alarm are integrally configured. A lost object prevention system is provided.

According to a second aspect of the present invention, when a signal transmitted from the receiver is radiated from the transmitter and a path of a radio wave returning to the receiver via the radio wave reflector is cut off, 2. A signal to be transmitted.
The present invention provides a forgotten item prevention system.

According to a third aspect of the present invention, the radio wave reflector receives the radio wave of the predetermined frequency radiated from the transmitter to the space, and synchronizes the radio wave with the inductor and the capacitor for storing energy. A rectifier for rectifying the received energy stored in the tank circuit, an oscillator driven by the DC voltage obtained by the rectification, and an antenna for radiating the oscillation output of the oscillator to space. A lost item prevention system according to claim 1 or 2 is provided.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a lost item prevention system according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a person, which holds a transceiver 2 in a pocket or the like, and carries a portable item 4 such as an umbrella to which a radio wave reflector 3 is attached or attached. FIG.
FIG. 3 is a block diagram showing the configuration of the transceiver 2, and FIG.
FIG. 3 is a circuit diagram showing a configuration of the radio wave reflector 3. Also,
FIG. 4 is a view for explaining the operation of the lost item prevention system according to one embodiment of the present invention.

The transmitter / receiver 2 shown in FIG. 2 includes a transmitter 21 and an antenna 22 for radiating radio waves to the space, an antenna 23 and a receiver 24 for receiving the radio waves returned from the radio wave reflector 3, An alarm device 25 is activated by a signal from the power supply 24, and a power supply unit 26 is provided by a battery for driving these units. The shape and weight of the alarm unit 25 are images of a mobile phone or PHS.

A radio wave reflector 3 shown in FIG. 3 includes an antenna 31 for receiving a radio wave radiated from the antenna 2, an inductor 32 and a capacitor 3 tuned to the received radio wave.
3, a rectifier 35 for rectifying the energy stored in the tank circuit 34 to extract a DC voltage, an oscillator 36 using a crystal oscillator or the like driven by the DC voltage, An antenna 37 radiates a transmission output as radio waves into space. Further, the shape of the radio wave reflector 3 is small because it does not have a power source, and it is sufficient to imagine a name tag to be attached to luggage. Since the rectifier 35 rectifies weak energy to extract a DC voltage, the rectifier 35 is required to have a small forward voltage drop and a high efficiency.

Next, the operation of the forgotten object prevention system having such a configuration will be described with reference to FIGS. 1, 2, 3 and 4. FIG. Radio waves are constantly radiated into the space via the antenna 22 from the transmitter 21 of the transceiver 2 held by the person 1. The intensity of the radio wave used here is a weak radio wave which does not violate the Radio Law, and the frequency is desirably a frequency in a long wave band where attenuation by an obstacle or the like is small.

The radio wave radiated from the antenna 22 is
When the portable product 4 is carried by the person 1 or is placed at a short distance, the inductor 31 reaches the antenna 31 of the radio wave reflector 3 attached or attached to the portable product 4 and tunes to the frequency of the radio wave. Energy is stored in a tank circuit 34 composed of the capacitor 32 and the capacitor 32. This stored energy is converted to a DC voltage by the rectifier 35,
The oscillator 36 is driven.

The oscillator 36 is a low power consumption oscillator constituted by a crystal oscillator or the like. In order to easily determine the frequency of a radio wave radiated from the transmitter 21 via the antenna 2, It oscillates at a frequency different from the frequency of radio waves. Further, the oscillation output of the oscillator 36 is radiated to the space via the antenna 37. here,
The portable article 4 is carried by the person 1 or placed at a short distance, and the radio wave radiated from the antenna 37 is received by the receiver 24 via the antenna 23 of the transceiver 2 held by the person 1. I have.

This corresponds to a period between time t0 and t1 or a period between t1 and t2 in FIG. 4, and is a case where the distance between the person 1 and the portable article 4 is less than the receivable distance d0. Usually, the output of the transmitter 21 is set such that the distance d0 is several meters. Further, if the distance between the person 1 and the portable device 4 exceeds d0 after the time t2 in FIG. 4, the radio wave from the transmitter 21 of the transceiver 2 does not reach the radio wave reflector 3 or the reflected radio wave disappears. Alternatively, since the intensity of the reflected radio wave from the radio wave reflector 3 becomes weak, the reflected radio wave does not reach the receiver 24 of the transceiver 2 held by the person 1.

At the critical point in such a state, the receiver 24 of the transceiver 2 sends a signal to the alarm device 25 and issues an alarm by a buzzer sound or the like. Here, the distance between the person 1 and the portable article 4 is reduced again, and when the distance becomes d0 at the time t3, the receiver 24 of the transceiver 2 can receive the reflected radio wave from the radio wave reflector 3, but at this time, the signal Is not sent and no alarm is issued. When time t0 is reached and the distance exceeds d0 again, an alarm is issued.

By performing the above-described operation, an alarm is issued when there is a possibility that a person may misplace the portable item, and the alarm notices the lost item and reverses the route of the traveled item to remove the portable item. Even if it is not found even after returning to picking up, an alarm is issued when the distance from the portable device exceeds a predetermined value again, so that it is impossible to leave the portable device forgotten.

The operation of one embodiment of the present invention has been described above in detail with reference to the drawings. However, the present invention is not limited to this embodiment, and a design change or the like may be made without departing from the gist of the present invention. The present invention is also included in the present invention. For example, the alarm may be not a buzzer sound but a vibration generated by a vibrator. Further, the alarm device may be configured to generate a short confirmation sound when the receiver becomes capable of receiving the radio wave from the radio wave reflector to indicate that the place where the portable article is placed is within a short distance. . The rectifier used for the radio wave reflector is not limited to the configuration of the single-phase full-wave rectifier shown in the embodiment, but may have any configuration.

[0017]

As described above, according to the present invention, an alarm is issued when the distance between a person and a misplaced portable item exceeds a predetermined value. Can be

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a lost item prevention system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of the transceiver 2 in FIG.

FIG. 3 is a circuit diagram showing a configuration of a radio wave reflector 3 of FIG.

FIG. 4 is a diagram for explaining the operation of the lost item prevention system according to the embodiment of the present invention shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Person 2 ... Transceiver 3 ... Radio wave reflector 4 ... Portable goods 21 ... Transmitter 22 ... Antenna 23 ... Antenna 24 ... Receiver 25 ... Alarm 26 ... Power supply unit 31 ... Antenna 32 ... Inductor 33 ... Capacitor 34 ... Tank Circuit 35 Rectifier 36 Oscillator 37 Antenna

Claims (3)

(57) [Claims] 1. A transmission for radiating radio waves of a predetermined frequency into space.
And the radio wave energy received or affixed or attached to
Rectified and used as a power source, different from the predetermined frequency
A radio wave reflector that radiates radio waves of a frequency into space, a receiver that receives radio waves radiated by the radio wave reflector, and an alarm that issues an alarm based on a signal transmitted from the receiver, and is driven by a battery. The lost item prevention system, wherein the transmitter, the receiver, and the alarm are integrally formed. 2. The signal transmitted from the receiver is a signal radiated from the transmitter and transmitted when a path of a radio wave returning to the receiver via the radio wave reflector is cut off. The forgotten thing prevention system according to claim 1, characterized in that: 3. The radio wave reflector, receives a radio wave of the predetermined frequency radiated from the transmitter to the space, and tunes to the radio wave and stores a tank circuit including an inductor and a capacitor; A rectifier for rectifying the received energy stored in the tank circuit; an oscillator driven by the DC voltage obtained by the rectification; and an antenna for radiating the oscillation output of the oscillator to space. The lost item prevention system according to claim 1 or 2.