JP3197411B2 - Vehicle remote control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote control device for a vehicle, and more particularly to a remote control device capable of preventing theft by copying.

[0002]

2. Description of the Related Art Conventionally, a remote control device for a vehicle has a predetermined ID when a push button switch is pressed from a transmitter.
An infrared signal obtained by modulating the code at a constant frequency is transmitted from the transmitter to the receiver on the vehicle side. The receiver of the vehicle receives this signal, determines whether the ID code matches the ID code in the memory in the receiver, and locks or unlocks the door or the like of the vehicle when the ID code matches.

[0003]

However, in recent years, remote control devices have been used in many products such as home audio-video devices for remote control. Some of these remote control devices copy transmission signals from other remote control devices,
A learning-type remote control device capable of transmitting a signal of the same ID code as the target remote control device is also used. However, if such a learning type remote control device is used, the ID code of the transmitter of the vehicle remote control device is copied, and there is a disadvantage that the vehicle may be stolen by a third party.

[0004] The present invention has been made in view of such a conventional problem, and it is an object of the present invention to prevent the receiver from operating even if a learning-type remote control device is used, thereby preventing the vehicle from being stolen. Is a technical issue.

[0005]

SUMMARY OF THE INVENTION The present invention is a remote control device for a vehicle having a transmitter and a receiver mounted on the vehicle, wherein the transmitter stores a transmission switch and a predetermined ID code. ID code memory, ID code reading means for reading an ID code in the ID code memory when a switch signal is input from a transmission switch,
Data modulation means for changing a modulation frequency in bits constituting the ID code signal based on the ID code signal read from the code reading means; and output means for driving a light emitting element by an output of the data modulation means. And a receiver, a light receiving unit that receives an optical signal output from the transmitter and converts it into an electric signal, and a bandpass filter that passes a frequency included in a modulation frequency among outputs from the light receiving unit, A waveform shaper for waveform shaping the output of the band-pass filter, an ID code storage unit for storing the same ID code as the transmitter, and a comparator for determining whether the ID code storage unit matches the received ID code. And an output unit for driving the control target based on the coincidence output from the unit.

[0006]

According to the present invention having such a feature, when the transmission switch of the transmitter is turned on, the ID code memory stores
The ID code is read by the D code reading means. Then, based on the ID code signal, the data modulator modulates the signal so that the frequency is different within at least one of the H level and the L level. The light emitting element is driven from the output means by the modulation signal. In reception on the vehicle side, this optical signal is received by a light receiving unit, converted into an electric signal, and at least a part of the modulation frequency is shaped into a waveform through a band-pass filter serving as a pass band. Then, the comparator determines whether the ID code matches the ID code in the ID code storage unit included in the receiver. Then, at the time of coincidence, the control target in the vehicle is driven.

[0007]

FIG. 1 is a block diagram showing a transmitter of a remote control device for a vehicle according to a first embodiment of the present invention. As shown in FIG. 1, the transmitter 1 includes a transmission switch 2 and a microcomputer 3 to which an output thereof is given, an infrared light emitting diode 4 as a light emitting element, and a transistor 5 for driving the infrared light emitting diode 4. A clock oscillator 6 is connected to the microcomputer 3. The microcomputer 3 has an ID code unique to the transmitter, as will be described later, in this embodiment, a 24-bit ID code.
An ID code memory 3a for holding a D code is provided. Every time the transmission switch 2 is turned on, the ID code is read from the ID code memory 3a, and the modulation frequency is continuously changed to enable the transmission transistor 5 to operate. It is driven. A battery 7 for supplying power to each unit is connected in the transmitter 1.

Next, the configuration of the receiver 11 will be described with reference to FIG. The receiver 11 in the vehicle is provided with a receiver 13 having a photodiode 12 as a light receiving means for receiving an infrared signal from the transmitter, and converts the infrared signal into an electric signal. The output of the receiving unit 13 is provided to a band pass filter (BPF) 15 via an amplifier 14. The band-pass filter 15 passes only a signal of a predetermined frequency including a part of the modulation frequency, for example, a signal around 40 KHz, and its output is supplied to the waveform shaper 16. The output from the waveform shaper 16 converts the obtained signal into a binary signal.
Given to. An ID code storage unit 18 is connected to the comparator 17. The ID code storage unit 18 is a storage unit that stores the same ID signal as the ID code memory 3a of the corresponding transmitter 1. The comparator 17 stores the ID code storage unit 1
8 is determined to match the received ID code. The coincidence output from the comparator 17 is sent to the control unit 19
To the output unit 20 together with a switch signal inside the vehicle. The control unit 19 drives the door of the vehicle in the lock or unlock direction via the output unit 20 based on the coincidence signal.

Next, the operation of this embodiment will be described with reference to the flowcharts of FIGS. In the flowchart shown in FIG. 3, when the transmission switch 2 is first turned on, the process proceeds from step 31 to step 32, where n, which is a pulse bit counter, is set to 1. Then, in a step 33, it is determined whether or not the n-th bit of the ID code held in the ID code memory 3a is 1. If 1, the timer A is set to, for example, 2.4 mS, and if 0, the timer A is set to 1.2 mS (steps 34 and 3).
5). Then, a pulse is output in a routine 36.
As shown in FIG. 4, the routine 36 first sets a predetermined time, for example, 50 μS in the timer register x (step 51). Then, the process proceeds to step 52, where 1 is output. Then, the infrared light emitting diode is driven via the output transistor 4, and an infrared signal is output. Next, the value of the timer register x is set to the timer B. Then, in step 54, the process waits for the timer B to time up. If the time is up, the process proceeds to step 55 to check whether the output is "1". In the initial state, since the output is set to 1 in step 52, the process proceeds from step 55 to step 56 to invert the output to 0. In step 57, a value obtained by subtracting a predetermined time, for example, 10 μS, from x is set as a new timer register value x, and the process proceeds to step 58 to check whether x is 0 or not. If x is not 0, the flow returns to step 53 to set the value of the timer register x to the timer B. Then, it waits for the timer B to expire (step 54), and proceeds to step 55 to repeat the same processing. In this case, FIG.
As shown in (a), a signal whose cycle becomes shorter sequentially is output.

Then, returning to step 37 in FIG. 4, the bit counter n is incremented, and the routine proceeds to step 38, where it is checked whether or not n is 25. If it is not 25, the process proceeds to step 39 to wait for the timer A to expire. When the time is up, the flow returns to step 33 to check whether the n-th bit of the next ID code is 1. By repeating the loop of steps 33 to 39, signals with different pulse periods are output in accordance with the stored ID codes. At this time, the ID code 1
Or, the cycle differs depending on 0, and H at the time of each rise
A signal in which the modulation frequency continuously changes to the level as shown in the routine 36 will be output. If the bit counter n reaches 25 in step 38, a pulse is output in a routine 40. With this pulse output, a process of continuously changing the modulation frequency is performed again as shown in FIG. Here, in steps 31 to 33, 37 and 38, the microcomputer 3 has achieved the function of the ID code reading means 3b for sequentially reading the ID code from the ID code memory 3a when the transmission switch 2 is turned on. 34, 35, 3
7 to 39 and the routines 36 and 40 achieve the function of the data modulating means 3c for changing the modulation frequency within one logical level of the ID signal.

As a result, as shown in FIG. 5A, a signal whose frequency changes continuously within one pulse is output. The spectrum of the modulated signal changes almost continuously from the straight line A to B in FIG. If the pass frequency of the band-pass filter 15 is set within this range, the change of the frequency of the transmission signal causes the band-pass filter 1 to change.
5 will pass. Therefore, even if the center frequency accuracy of the bandpass filter 15 is low, the degree of separation of the bandpass filter 15 of the receiver can be increased, and the noise resistance can be improved.

Here, the learning type remote control device will be described with reference to FIG. In the learning type remote control device, as shown in FIG. 7 (a), a remote control device 61 to be learned and a learning type remote control device 62 are arranged facing each other. The learning type remote control device 62 has a light receiving portion that receives an infrared signal transmitted from another remote control device 61, a detection portion that detects a pulse width and a modulation frequency of the output, and a memory that holds these data. are doing. Then, as shown in FIG. 7A, the target remote control device 61 is set to the transmission mode, and this signal is received in the learning type remote control device, and the period, the transmission time and the frequency are detected. That is, FIG.
As shown in (c), in the signal (A) of the first bit,
The H level time T _1a , its period T _2a and modulation frequency f _1a are detected and stored in the memory as data. Similarly, in the signal (B) of the second bit of the time, the time T _{1b of the} H level, the cycle T _2b and the frequency f _2b are determined and stored in the memory. The data shown in FIG. 7C is stored for all the transmitted signals in the number of transmitted bits. After the learning, the same data as the data can be transmitted based on the data.

Here, a case where learning is performed by the learning type remote control device 62 using the transmitter 1 according to the present invention instead of the target remote control device 61 will be considered. As described above, in the transmitter 1 according to the present invention,
The modulation frequency at the H level changes continuously. Therefore, in the learning type remote control device 62, H
Since the frequency within the period T1 of the level cannot be set accurately, the learning type remote control device 62
The D code will not be stolen.

In the first embodiment, the frequency is continuously changed only when the ID code is at the H level. However, the modulation frequency may be changed only when the ID code is at the L level. The oscillation frequency may be continuously changed at both the H level and the H level.

Next, a second embodiment of the present invention will be described. In the first embodiment described above, the modulation frequency is changed almost continuously when the output is at the H level.
Even at the H level, a plurality of types of modulation frequencies are used, and these frequencies are changed. For example, as shown in FIG. 5B, the modulation frequencies at at least one of the logical levels, for example, the H level, are f1 and f2, and these are alternately switched and used for the "1" and "0" signals. Also in this case, if the frequency f2 passes through the band-pass filter 15 on the receiver side, the learning type remote control device 62
In this case, since the initial frequency is stored or the modulation frequency cannot be detected, the security can be improved without being copied.

[0016]

As described in detail above, in the remote control device according to the present invention, when transmitting the ID code signal from the transmitter, the ID code signal is transmitted while changing the modulation frequency. Therefore, the transmission signal of the remote control device according to the present invention cannot be copied even by the learning type remote control device, and the transmitter of the learning type remote control device cannot be used. Therefore, an effect is obtained that the signal for door lock and unlock of the vehicle is not stolen and the safety can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a transmitter of a remote control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a receiver of the remote control device according to the first embodiment.

FIG. 3 is a flowchart illustrating an operation of the transmitter according to the first embodiment.

FIG. 4 is a flowchart illustrating a pulse output process of the transmitter according to the first embodiment.

5A is a waveform diagram illustrating an ID code signal transmitted from the transmitter according to the first embodiment, and FIG. 5B is a waveform diagram illustrating an ID code signal transmitted from the transmitter according to the second embodiment.

FIG. 6 is a graph showing a spectrum change of a modulation frequency of a transmitter and a selection characteristic of a band-pass filter of a receiver according to the first embodiment of the present invention.

7A is a perspective view showing a state in which a code is learned using a learning type remote control device, FIG. 7B is an ID code signal of a remote control device to be learned, and FIG. 4 is a memory map showing a memory of a learning type remote control device in which is stored as data.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmitter 2 Transmission switch 3 Microcomputer 3a ID code memory 3b ID code reading means 3c Data modulation means 4 Light emitting diode 5 Transistor 11 Receiver 12 Photodiode 13 Receiver 14 Amplifier 15 Bandpass filter 16 Waveform shaper 17 Comparator 18 ID code storage unit 19 control unit 20 output unit

────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Masatoshi Shimohira 2254-2 Kirin, Iida-shi, Nagano Prefecture OMRON Iida Co., Ltd. (56) References JP-A-62-264280 (JP, A) JP-A-5-287947 ( JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E05B 49/00-49/04 B60R 25/00-12/10 G08B 23/00-31/00 H03J 9/00-9 / 06 H04Q 9/00-9/16

Claims (1)

(57) [Claims] 1. A remote control device for a vehicle having a transmitter and a receiver mounted on a vehicle, the transmitter comprising: a transmission switch; an ID code memory for storing a predetermined ID code; ID code reading means for reading an ID code in the ID code memory when a switch signal is input from the transmission switch; and forming the ID code signal based on the ID code signal read from the ID code reading means. Data modulation means for changing a modulation frequency within a bit to be transmitted, and output means for driving a light emitting element by an output of the data modulation means, wherein the receiver outputs from the transmitter. Light receiving means for receiving the converted optical signal and converting the light signal into an electric signal; and passing a frequency included in the modulation frequency in an output from the light receiving means. A band-pass filter, a waveform shaper that shapes the output of the band-pass filter, an ID code storage unit that stores the same ID code as the transmitter, and a match between the ID code storage unit and the received ID code. A remote control device for a vehicle, comprising: a comparator for judging the condition; and an output unit for driving a control target based on the coincidence output from the comparator.