JPH08339487A - Portable terminal device - Google Patents

Abstract

PURPOSE: To make a terminal device body issue an alarm if the operator leaves the terminal device behind and inform of leaving by carrying a transmitter which receives a radio wave and responds, and equipping the portable terminal device body with a transmitting and receiving circuit for the radio wave. CONSTITUTION: The portable terminal device body 10 sends the radio wave as an actuation signal for the transmitter 20 for a specific time. A reception mode is entered the specific time later, a signal sent back from the transmitter 20 is expected, and a data check is made on receiving a signal characteristic of the transmitter 20, e.g. a radio wave modulated with the identification number. In this case, no response from the transmitter 20 is included in NO judgements by the data check. When NO is judged by the data check, a normal process is interrupted and abnormality is displayed. Then a command is resent by an antenna 6. When there is no response, the buzzer of the portable terminal device body 10 issues an alarm. Further, the electric power, etc., of the actuation signal radio wave is adjusted and an alarm is sent by the data check.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable terminal device having a misplacement prevention mechanism. In particular, the present invention relates to a handheld computer, but it is also applicable to a laptop type or notebook type personal computer.

[0002]

2. Description of the Related Art In recent years, various portable terminal devices having data input means and display means, which are also called handheld computers or handy terminals, have been put into practical use. This type of portable terminal device is a kind of computer that is small and lightweight, and is used in various fields because it enables various data processing at the carrying destination.

Recently, it has been used outdoors. This kind of portable terminal device has a built-in storage device such as a RAM pack, which temporarily stores data and is directly connected to a host computer as a post-process or indirectly connected by a telephone line or the like. However, the final processing is usually performed.

This type of small and lightweight portable terminal device has a great feature that it is easy to carry, but because it is easy to misplace it, measures for preventing misplacement have become a major issue. That is, this type of portable terminal device often stores highly important and highly confidential information such as a password for connecting to a host computer. Due to the risk of plagiarism, a measure to prevent misplacement of a portable terminal device has become a major issue.

In the conventional portable terminal device of this type, there has been a method of connecting the operator of the terminal device and the terminal device body with a chain as a measure for preventing misplacement. However, it is a cumbersome and inconvenient method for the operator to be always connected to the main body by a chain. In particular, when operating the terminal device while doing other work at an outdoor work site, the work may be supported while the terminal device is held, which may be dangerous in some cases. Further, when a single portable terminal device is used by a plurality of operators, this chain connection method is very inconvenient.

As a general misplaced device, a device using wireless communication is commercially available. This device consists of a pair of transmitters and receivers, transmitting and receiving a specific frequency between the transmitters and receivers, and when the distance between the transmitters and receivers increases and it becomes difficult to receive radio waves, an alarm is issued and it is left behind. It is intended to prevent misplacement by evoking.

In a portable terminal device, one transceiver is connected to the terminal device and the other transceiver is carried by an operator to prevent misplacement, but both transceivers require a power source battery. Therefore, it cannot be said that it is smaller and lighter than the small and lightweight portable terminal device, and in particular, it is not sufficiently small and light for an operator to carry. In addition, it is necessary to replace the battery periodically, and if the power is cut off, the device will of course not operate. Therefore, there are problems in portability, maintainability, and reliability. Furthermore, when one portable terminal device is used by a plurality of operators, a plurality of sets of transmitters / receivers are required, and the number of transmitters / receivers connected to the portable terminal device main body increases, greatly impairing the portability of the terminal device main body. It was a thing.

[0008]

As described above, the conventional portable terminal devices have not been sufficiently provided with effective measures for preventing misplacement, and in recent years, in particular, they are small, lightweight and have high performance. With the advent of large-capacity portable terminal devices, reliable misplacement prevention measures without impairing portability have become essential.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a portable terminal device equipped with a mechanism for preventing misplacement of the terminal device body, which is excellent in maintainability and reliability without impairing portability. And

[0010]

SUMMARY OF THE INVENTION One invention of the present invention is
A portable terminal device body having a transmission circuit for transmitting a radio wave of a specific frequency over a certain area, and a circuit for receiving a radio wave transmitted from the portable terminal device body to obtain a power source, A transmitter carried by an operator having a circuit for transmitting a specific signal in response to the portable terminal device body by radio waves, and the portable terminal device body receives the radio wave transmitted from the transmitter. A portable terminal device, comprising: a receiving circuit; and a circuit for determining whether or not a misplaced state is present based on the contents received by the receiving circuit.

Another invention is the above-mentioned portable terminal device, which comprises one portable terminal device main body and a plurality of transmitters, each of which responds by transmitting a unique signal radio wave. The portable terminal device is characterized in that the receiving circuit of the main body of the portable terminal device identifies a plurality of transmitters by receiving signal radio waves of the transmitter at regular intervals.

[0012]

[Operation] An operator operating the main body of the portable terminal device
It is difficult to identify the signal radio wave from the transmitter carried by the operator without leaving the power supply, that is, in the state where transmission and reception are possible, when accidentally leaving from there, that is, when leaving the device by mistake. When the operator leaves the portable terminal device body up to a certain distance, it is possible to prevent the portable terminal device body from being left behind by determining that the portable terminal device body is left behind.

Further, since the radio wave from the main body of the portable terminal device is received and used as the power source of the transmitter, a power source such as a battery is not required in the transmitter, and the transmitter can be made ultra-compact and ultra-lightweight. It can be very portable. Furthermore, since it is not necessary to periodically replace the battery, the maintenance workability is excellent, and the battery does not run out without the operator's knowledge and the device does not operate. Therefore, the reliability is excellent.

Further, since the plurality of transmitters each have a unique signal code, the portable terminal device can handle only one receiving circuit by transmitting the corresponding code.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a portable terminal device body and a transmitter according to an embodiment of the present invention. In FIG. 1, the misplacement prevention mechanism includes a portable terminal device body 10 and a transmitter 20.
The portable terminal device body 10 includes a microprocessor 1, a clock oscillation circuit 2, a misplacement prevention determination program 13 in the memory 3, an antenna 6, a transmission circuit 7, a reception circuit 8, a display device 4, and an alarm circuit. It has 12 etc.

The oscillator 20 is an rectifier 2 including an antenna 21 composed of a coil and a tuning capacitor, and a power supply capacitor.
2, a memory 23 in which the receiving module is written in advance, a signal generator 2 that reads the receiving module and modulates a transmission wave
4 and transmitter 25.

FIG. 2 is a flowchart of the misplacement detection process. FIG. 3 is a cross-sectional perspective view of a transponder used in a wireless module "Tyris" manufactured by Texas Instruments, Inc., which is used as an embodiment of the oscillator of the present invention.

The misplacement detection process of the portable terminal device will be described with reference to FIGS.

The power of the portable terminal device body 10 is turned on (step S31). Then, initialization is performed to confirm that communication can be normally performed (step S32). Transmitter 20
Radio signal (134.2
KHz) is transmitted for 50 msec (step 3)
3). After the lapse of 50 msec, the reception mode is set, and a reply from the transmitter is awaited (steps S34 and S35). A signal peculiar to the transmitter 20, for example, an electric wave which is modulated by an identification number is received and a data check is performed. In this case, no response from the transmitter is also included in the judgment of NO in the data check (step S36). If the result of the data check is NO, the normal processing is interrupted and an abnormality is displayed (step S37). Then retransmit the command, ie step S
A transmission radio wave similar to 33 is radiated from the antenna 6 (step S38). If there is no response, an alarm is output by the buzzer built into the portable terminal device body (step S
39). Note that the buzzer cannot be heard if the operator is more than a few meters away. Therefore, by adjusting the power of the start signal radio wave, the power of the radio wave emitted from the transmitter, the received radio wave level that determines that there is no response, etc., an alarm can be issued by a data check when the alarm recognition range of the operator is exceeded. it can. If a response is received, the process returns to the normal process (step S40). Thereafter, the misplacement detection is repeated in the interrupt process (step S41) at regular time intervals in the normal process.

On the other hand, in the transmitter carried by the operator, the radio wave transmitted in step S33 is converted into DC power and stored in the power supply capacitor (step S50). After confirming that the stored energy is sufficient to respond, the data in the memory is read out, the carrier wave is thereby modulated (step S51) and transmitted from the antenna 21 (step S52).

The component structure of the transponder corresponding to the oscillator of the present invention shown in FIG. 3 includes a coil 21 serving as an antenna, a tuning capacitor 28, a power source capacitor 29, a DC converter circuit, a memory, a modulator circuit and a transmitter circuit. It is composed of a 1C package 26 and a glass case 27 for protecting them.

Since this transponder does not require a battery and is small in size, it can be incorporated in a ballpoint pen or the like, so that the operator does not have to be conscious of carrying it.

Next, when a plurality of operators carry their respective oscillators, as shown in FIG. 4, an activation signal is sent from the portable terminal device body to activate the oscillators. The code of the corresponding transmitter is transmitted from the portable terminal device body.
Each transmitter compares the received code with its own code, and if they do not match, continues the process and ends. When the codes match, a confirmation signal is sent. After receiving the confirmation code, the portable terminal device main body performs processing.

The above processing is repeated for each transmitter code by sequentially changing the transmitter code.

[0025]

As described above in detail, according to the present invention, an operator carries a transmitter (transponder) which receives and responds to radio waves, and a portable terminal device main body is provided with a radio wave transmission / reception circuit. By doing so, when the operator inadvertently leaves the portable terminal device behind, the portable terminal device main body generates an alarm, and the operator can be notified to prevent the portable terminal device from being left behind.

Further, the plurality of transmitters emit radio waves modulated by their respective signals, and the receiving circuit (portable terminal device main body) identifies the modulated signals of the plurality of transmitters. One can support multiple transmitters, and 1
Even when a single portable terminal device is used by a plurality of operators, only one receiving circuit is required, and the portability of the portable terminal device is not impaired.

Further, the transmitter does not require a power source such as a battery, and can be made ultra-compact and ultra-light, and can be incorporated into a very portable device such as a ballpoint pen, so that the operator can carry it. Never identify. Further, since it is not necessary to periodically replace the battery, maintenance workability and reliability are excellent.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a portable terminal device having a misplacement prevention mechanism according to an embodiment of the present invention.

FIG. 2 is a flowchart of a misplacement detection process of the portable terminal device according to the present invention.

FIG. 3 is a partial cross-sectional perspective view of an oscillator according to an embodiment of the present invention.

FIG. 4 is a flowchart of misplacement detection processing when there are a plurality of transmitters according to the present invention.

[Explanation of symbols]

 10 Portable terminal device body 20 Transmitter

Claims (2)

[Claims] 1. A portable terminal device body having an oscillator for transmitting a radio wave of a specific frequency over a fixed area, and a circuit for receiving a radio wave transmitted from the portable terminal device body to obtain a power source. And a transmitter carried by an operator having a circuit that responds to the portable terminal device body with a specific signal by radio waves, and the portable terminal device body transmits the radio wave transmitted from the transmitter. A portable terminal device, comprising: a receiving circuit for receiving, and means for determining whether or not a misplaced state is present based on the content received by the receiving circuit. 2. The portable terminal device according to claim 1, comprising one portable terminal device main body and a plurality of transmitters, each of which responds by transmitting a unique signal wave.
A portable terminal device, wherein a receiving circuit of the portable terminal device body identifies a plurality of transmitters by receiving signal radio waves of the transmitter at regular intervals.