JP2001090403A - Unlocking system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an unlocking system to surely execute locking and unlocking operations by improving the securability of the system by converting transmission codes continuously transmitted from a transmitter by a rolling code method. SOLUTION: A timer 212 is incorporated in a receiver 202 and the count value of transmission codes is predicted from the time difference between the preceding receiving time and present receiving time. When the count value falls within a predicted range, an unlock system executes unlocking operations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unlocking device used in, for example, a keyless entry system of an automobile.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 9-4293 discloses that a fixed transmission code is continuously transmitted from a transmitter, a receiver checks an ID code from the transmission code, the ID code matches, and It has been proposed to perform unlocking when a lock intention is detected.

[0003]

However, in the above-mentioned prior art, since a fixed transmission code is transmitted, there is an inconvenience that when the transmission code is decrypted, copying is relatively easily performed.

In order to improve the security of the keyless entry system, a so-called rolling code is used. This rolling code
Even if the content of the information to be transmitted from the transmitter is the same, it is converted to a different code at each transmission and then transmitted, the code is received by the receiver and restored, A code system intended to prevent vehicle theft by copying radio waves.

When a rolling code is used, the transmitter uses a transmitter ID for generating the rolling code.
The code and the count value for counting the number of times of transmission are stored, and the count value is updated (+1 is added) every time the code is transmitted from the transmitter. By generating a rolling code using this count value, a different code is generated and transmitted each time. On the other hand, the receiver obtains an ID code and a count value for counting the number of transmissions by restoring the signal received from the transmitter, and the obtained ID code is identical to the ID code of the transmitter stored in advance. If the obtained count value is larger than the previous count value (or smaller than a value obtained by adding a predetermined value to the previous count value), it is determined that the transmission code received this time is legitimate. . Here, the case where the calculated count value is larger than the previous count value is that, in an actual use environment, the case where the radio wave transmission environment between the transmitter and the receiver is favorable is small, and This is because a case where the operation of the transmitter is not performed toward the receiver (for example, a case where the user repeatedly presses the operation key with his / her hand) must be assumed.

[0006] However, the rolling code can be up to 256 counts when the counter is 8 bits, but an upper limit (for example, 30 times) is provided for the number of transmissions in consideration of a case where the count value is excessively increased. This upper limit value is set to a number of times that it is unlikely to perform a switch operation (idle shooting) between the time of getting off last time and the time of getting on this time.

When a rolling code is employed in the system disclosed in Japanese Patent Application Laid-Open No. 9-4293 to improve security, a transmission code is transmitted every two seconds. It may not be possible to unlock until reset again. If the upper limit is increased to solve this problem, the transmission code will be easily decoded.

[0008] The present invention has been made in view of the above, and an object of the present invention is to convert a transmission code continuously transmitted from a transmitter by a rolling code method to enhance security.
An object of the present invention is to provide an unlocking device capable of reliably performing a locking and unlocking operation.

[0009]

SUMMARY OF THE INVENTION To solve the above problems,
In order to achieve the object, the unlocking device of the present invention has the following configuration. That is, transmitting means for converting the identification information including the number of transmissions and transmitting the information at predetermined time intervals, and restoring the identification information received from the transmitting means, wherein the number of transmissions is within a predetermined regulation value, and the identification information is Receiving means for determining whether or not the information is authentic, wherein the unlocking device unlocks the locking means based on the determination result of the receiving means. And the number of transmissions included in the identification information is predicted based on the result of the clocking by the clocking means, and the locking means is unlocked if the number of transmissions is within the predicted range.

[0010] The unlocking device of the present invention has the following configuration. That is, a transmitting unit that converts the identification information and transmits it at predetermined time intervals, and a receiving unit that restores the identification information received from the transmission unit and determines whether the identification information is legitimate, The locking means is unlocked when the identification information is valid and the valid identification information is correctly received a plurality of times.

Further, the unlocking device of the present invention has the following configuration. That is, transmitting means for converting the identification information including the number of transmissions and transmitting the information at predetermined time intervals, and restoring the identification information received from the transmitting means, wherein the number of transmissions is within a predetermined regulation value, and the identification information is Receiving means for determining whether or not the data is authenticated, wherein the unlocking device unlocks the locking means based on the determination result of the receiving means, wherein the transmitting means transmits the number of transmissions a plurality of times. Count.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. [System Configuration] FIG. 1 is a diagram showing a keyless entry system of the present embodiment.

In the figure, 101 is a transmitter, 200 is a receiver 2
02. The transmitter 101 has two push-down operation key switches (hereinafter, operation keys) X, Y
The operation key X is a door lock key, and the operation key Y is a door unlock key.

The transmitter 101 is operated by a battery 107,
When the operation key X or Y is pressed, a "lock command" or "unlock command" of a predetermined format is converted into a radio signal and transmitted to the receiving side via the antenna 102, and the transmitter is transmitted at predetermined time intervals. “ID code” which is a unique identification number of the transmitter 101 and the transmitter 10
The “count value” indicating the number of transmissions of 1 is converted into a radio signal and transmitted to the receiving side via the antenna 102.

An automobile 200 includes an antenna 201 for receiving a radio signal from the transmitter 101, a receiver 202 having a microcomputer 207, and a door lock control unit (hereinafter, DCU) for operating a door lock actuator (not shown) according to a command from the microcomputer 207. 20)
3 is provided.

Next, the circuit configurations and operations of the transmitter 101 and the receiver 202 will be described. [Structure and Operation of Transmitter 101] FIG. 2 is a block diagram showing the transmitter of the present embodiment.

In FIG. 1, a transmitter 101 includes an internal antenna 102, a nonvolatile writable memory 103, a high-frequency oscillation circuit 104, a microcomputer (hereinafter, microcomputer) 10 in addition to a battery 107 for driving the transmitter 101.
5, a reset circuit 106, and operation keys X and Y, and a timer 108 for measuring a transmission interval. The microcomputer 1
05 is a CPU 105A, a RAM 105B and a ROM
105C, and the CPU 105A
The microcomputer 105 and the entire transmitter 101 are operated according to the program stored in 05C.

Next, the operation of the transmitter 101 will be described.

In the transmitter 101, when a predetermined time has elapsed from the previous transmission by the timer 108, the reset circuit 106 sends a reset pulse to the microcomputer 105. When a reset pulse is input, the microcomputer 105 starts up and starts operation, and executes initial settings. After the initialization, the microcomputer 105 stops the reset circuit 106, reads out the “ID code” and the “count value”, and stores them in the RAM 105B inside the microcomputer 105. Next, the microcomputer 105
Reads the “ID code” and “count value” stored in the RAM 105B, converts them into rolling codes, and converts them by a pulse width modulation (PWM) method. The pulse is input to the oscillation circuit 104, and the oscillation circuit 104 modulates and amplifies the input pulse from the microcomputer 105 and transmits it as a radio signal. The transmitter 101 repeats such a transmission operation and transmits a transmission code every predetermined time.

On the other hand, in the transmitter 101, when any one of the operation keys X and Y is pressed, the reset circuit 106 sends a reset pulse to the microcomputer 105. When a reset pulse is input, the microcomputer 105 starts up and starts operation, and executes initial settings. After the initialization, the microcomputer 105 stops the reset circuit 106 and
A “lock command” or an “unlock command” and an “ID code” are read in accordance with the operation key pressed from, and stored in the RAM 105B inside the microcomputer 105. Next, the microcomputer 105 reads out the “lock command” or “unlock command”, the “ID code”, and the “count value” stored in the RAM 105B, converts them into rolling codes, and converts them into pulse width modulation (PWM). The pulse is input to the oscillation circuit 104,
The oscillating circuit 104 modulates and amplifies the input pulse from the microcomputer 105 and transmits it as a radio signal.

That is, the transmitter 101 has two transmission operations: a non-operation transmission that is continuously transmitted at predetermined time intervals, and an operation transmission that is transmitted by pressing the operation keys X and Y.
[Rolling code method] The transmission code of the transmitter 101 is, for example, 16 bits, of which the ID code is 8
The bit and the count value are 8 bits. The count value is incremented by one for each transmission. Then, the 16-bit transmission code combined with the ID code is converted into a rolling code by a predetermined method.

The receiver 202 restores the transmission code and
Check the D code. If the count value has not increased (decreased) since the previous reception, unlocking is not performed even if the ID codes match. Further, even if the count value is extremely increased, the unlock is not performed.

For example, if the counter is 8 bits, 2
56 counts are possible, and the upper limit of the number of transmissions is set to 30 in consideration of the case where the count value has increased too much. In the normal case, 30
No switch operation (air strike) is performed. [Configuration and Operation of Receiver 202] FIG. 3 is a block diagram showing a receiver according to the present embodiment.

In the figure, a power source is supplied to a receiver 202 from a battery 211 of a vehicle body, and the voltage is supplied to a power source circuit 20.
The voltage is made constant by 8 and used. Also, the receiver 202
Is an antenna 20 for receiving a radio wave from the transmitter 101
1. a signal receiving circuit 210 for detecting and demodulating a received radio wave;
A reset circuit 209 for resetting the microcomputer 207 when the power is turned on, a nonvolatile writable memory 204 storing “ID code” and “count value”, and an output circuit 206 for transmitting a signal from the microcomputer to the DCU 203. Prepare. Note that the microcomputer 207 is a CPU 20
7A, a RAM 207B, and a ROM 207C, and the CPU 207A operates the microcomputer 207 and the entire receiver 202 according to a program stored in the ROM 207C in advance.

Next, the operation of the receiver 202 will be described. An unillustrated area of the memory 204 includes a plurality of “IDs”.
The "code" and the "count value" are stored, and are read out to the RAM 207B and used when the microcomputer 207 starts resetting.

The signal receiving circuit 210 subjects the radio signal or noise received by the antenna 201 to pulse width modulation (PW
The signal is demodulated by the M) method, decoded into digital data, and sent to the microcomputer 207. The microcomputer 207 performs an inverse conversion of the digital data from the signal receiving circuit 210 from the rolling code, and determines whether the radio wave signal received this time is addressed to the receiver. When the digital data is addressed to the own receiving circuit, the microcomputer 207
B, which is temporarily stored in an area (not shown), data corresponding to an ID code and a count value for counting the number of transmissions is obtained, and the obtained ID code matches one of the ID codes stored in the RAM 207C, And it is determined whether or not the obtained count value is larger than the previous count value. At this time, the determination of the ID code is to be performed by a process described later. As a result, if it does not include the ID code stored in advance, the digital data once stored in the RAM 207B is ignored. On the other hand, when the digital data includes an ID code stored in advance,
It detects whether the predetermined command field in the digital data is 1 or 0. For example, if it is 1, it is determined that it is a "lock command", and if it is 0, it is determined that it is an "unlock command". When a command included in the received signal is detected in this way, a signal is output to the DCU 203 to lock or unlock the door according to the command. On the other hand, when the digital data does not include a predetermined command field, the digital data once stored in the RAM 207B is ignored.

In this embodiment, the memories 103, 20
4 EEPROM (electrically erasable programable
ROM). [Operation of Receiver of First Embodiment] Next, the operation of the receiver 202 of the first embodiment will be described with reference to FIG.

FIG. 4 is a flowchart illustrating the operation of the receiver according to the first embodiment.

In the figure, an ID code and a count value obtained from a received transmission signal are stored in a RAM 207B of the receiver 202.

In the first embodiment, a timer 212 is provided in the receiver 202, and the count value of the transmission code is predicted based on the time difference between the previous reception and the current reception, and if the count value is within the prediction range, unlocking is performed. Execute.

Specifically, as shown in FIG. 4, in step S1, a transmission code is received. In step S2, the transmission code is inversely converted to restore the ID code and the count value. In step S3, it is determined whether the ID codes match. If the ID codes match in step S3 (YES in step S3), the process proceeds to step S4 and the ID
If the codes do not match (NO in step S3), the process returns to step S1.

In step S4, the count value is equal to the predicted value A
It is determined whether it is less than. The predicted value A is set to the sum of the quotient of the timer value and the transmission time interval (for example, 2 seconds), the count value at the previous reception, and the allowable value. If the count value is less than the predicted value A in step S4 (YES in step S4), the process proceeds to step S5, and if the count value is not less than the predicted value A (NO in step S4), the process returns.

At step S5, the count value is equal to the predicted value B.
Is determined. The predicted value B is set to a value obtained by subtracting the allowable value from the sum of the quotient of the timer value and the transmission time interval (for example, 2 seconds) and the count value at the previous reception. If the count value exceeds the predicted value B in step S5 (YES in step S5), the process proceeds to step S6, and if the count value does not exceed the predicted value B (NO in step S5), the process returns.

In step S6, since the count value is within the prediction range, unlock is executed.

According to the first embodiment, the count value of the transmitter is predicted by the receiver, and if the count value is within the prediction range (A> count value> B), the unlock is executed. It is possible to enhance security without increasing, and to execute locking and unlocking operations reliably. [Operation of Receiver of Second Embodiment] Next, the operation of the receiver 202 of the second embodiment will be described with reference to FIG.

FIG. 5 is a flowchart for explaining the operation of the receiver according to the second embodiment.

In the second embodiment, the receiver 202 unlocks when a correct transmission code of the conversion method is correctly received plural times.

Specifically, as shown in FIG. 5, in step S11, a transmission code is received. In step S12, the transmission code is inversely converted to restore the ID code and the count value. In step S13, it is determined whether the ID codes match. If the ID codes match in step S13 (YES in step S13), the process proceeds to step S14, and if the ID codes do not match (N in step S13).
O), returning to step S11.

In step S14, it is determined whether or not the reception is the first reception after locking. If it is not the first reception after locking in step S14 (NO in step S14), step S14
At 15, the counter 2 is set to the current count value. If it is the first reception after locking in step S14 (step S1
In step S16, the counter 1 is set to the current count value.

In step S17, it is determined whether or not the value obtained by subtracting counter 1 from counter 2 is smaller than an allowable value. If the subtraction value of the counters 1 and 2 is less than the allowable value in step S17 (YES in step S17), the process proceeds to step S18, and if the count value is not less than the allowable value (step S17).
(NO at 17), the process proceeds to step S19.

In steps S18 and S19, the value of the counter 1 is set to the value of the counter 2.

In step S20, the counter 3 is incremented. The counter 3 is a counter for preparing for unlocking.

In step S21, it is determined whether or not the value of the counter 3 exceeds an allowable value. If it exceeds the allowable value in step S21 (YES in step S21), unlock is executed in step S22. On the other hand, step S2
If the counter 3 does not exceed the allowable value at 1 (step S
(NO at 21), and returns to step S11.

According to the second embodiment, the unlock is executed when the correct transmission code of the conversion method is correctly received a plurality of times. Therefore, the security is improved without increasing the upper limit of the number of transmissions, and the security is improved. Lock and unlock operations. [Operation of Transmitter of Third Embodiment] Next, the operation of the transmitter 101 of the third embodiment will be described with reference to FIG.

FIG. 6 is a flowchart for explaining the operation of the transmitter according to the third embodiment.

In the third embodiment, the counter of the transmitter 101 is incremented every plural times (for example, every ten transmissions).

Specifically, as shown in FIG. 6, in step S31, the ID code and the count value are read. In step S32, the ID code and the count value are encrypted with the rolling code. In step S33, the encrypted code is transmitted.

In step S34, it is determined whether the transmission code has been transmitted a predetermined number of times (for example, 10 times). If transmission has been performed a predetermined number of times in step S34 (YES in step S34), the counter is incremented in step S35, and if transmission has not been performed the predetermined number of times in step S34 (NO in step S34), the process returns to step S33.

According to the third embodiment, the transmitter 101
The counter is incremented a plurality of times (for example, every ten transmissions), the security is improved without increasing the upper limit of the number of transmissions, and the locking and unlocking operations can be executed reliably. [Operation of Receiver of Fourth Embodiment] Next, the operation of the receiver 202 of the fourth embodiment will be described with reference to FIG.

FIG. 7 is a flowchart for explaining the operation of the receiver according to the fourth embodiment.

In the first embodiment, when the engine is started, the power supply voltage of the receiver temporarily drops, the timer value is reset or invalidated, and unlocking may not be executed. For this reason, in the fourth embodiment, after the engine is started, the ignition switch is turned on with the ignition key being inserted into the key cylinder, and since the driver is riding, the receiver continuously transmits the correct transmission code of the conversion method. In a receivable state. Therefore, when these conditions are satisfied, the count value stored in the receiver is updated, and the timer of the receiver is reset so that a correct count value can be predicted.

Specifically, as shown in FIG. 7, in step S41, a transmission code is received. In step S42, the transmission code is inversely converted to restore the ID code and the count value. In step S43, it is determined whether or not the ID codes match. If the ID codes match in step S43 (YES in step S43), the process proceeds to step S44, and if the ID codes do not match (N in step S43).
O), returning to step S41.

In step S44, it is determined whether or not the first reception is performed after the engine is started. If it is not the first reception after starting the engine in step S44 (N in step S44
O) In step S45, the counter 2 is set to the current count value. If it is the first reception after the engine is started in step S44 (YES in step S44), step S46 is executed.
To set the counter 1 to the current count value.

In step S47, it is determined whether the value obtained by subtracting the value of the counter 1 from the value of the counter 2 is smaller than the allowable value. If the subtraction value of the counters 1 and 2 is less than the allowable value in step S47 (YES in step S47), the process proceeds to step S48, and if the count value is not less than the allowable value (step S47).
(NO at 47), and proceeds to step S49.

In step S48, the timer value and the count value are updated.

In step S49, the value of counter 1 is set to the value of counter 2.

According to the fourth embodiment, since the timer value and the count value are updated after the engine is started, a correct count value can be predicted, the security can be improved without increasing the upper limit of the number of transmissions, and the lock can be reliably performed. And an unlock operation. [Operation of Receiver of Fifth Embodiment] Next, the operation of the receiver 202 of the fifth embodiment will be described with reference to FIG.

FIG. 8 is a flowchart for explaining the operation of the receiver according to the fifth embodiment.

As in the fourth embodiment, immediately after the engine is stopped, the ignition key is inserted into the key cylinder until immediately before the engine is stopped, and since the driver is riding the vehicle, the receiver transmits the correct transmission code of the conversion method. It is in a state where reception is possible continuously. Therefore, when these conditions are satisfied,
The count value stored in the receiver is updated, and the timer of the receiver is reset so that a correct count value can be predicted.

Specifically, as shown in FIG. 8, in step S51, a transmission code is received. In step S52, the transmission code is inversely converted to restore the ID code and the count value. In step S53, it is determined whether the ID codes match. If the ID codes match in step S53 (YES in step S53), the process proceeds to step S54, and if the ID codes do not match (N in step S53).
O), returning to step S51.

In step S54, it is determined whether or not the first reception is performed after the engine is stopped. If it is not the first reception after stopping the engine in step S54 (N in step S54
O) In step S55, the counter 2 is set to the current count value. If it is the first reception after stopping the engine in step S54 (YES in step S54), step S56
To set the counter 1 to the current count value.

In the step S57, it is determined whether or not the value obtained by subtracting the counter 1 from the counter 2 is smaller than an allowable value. If the subtraction value of the counters 1 and 2 is less than the allowable value in step S57 (YES in step S57), the process proceeds to step S58, and if the count value is not less than the allowable value (step S57).
(NO at 57), the process proceeds to step S59.

In step S58, the timer value and the count value are updated.

In step S59, the value of counter 1 is set to the value of counter 2.

According to the fifth embodiment, since the timer value and the count value are updated after the engine is started, the correct count value can be predicted, the security can be improved without increasing the upper limit of the number of transmissions, and the lock can be reliably performed. And an unlock operation. [Operation of Receiver of Sixth Embodiment] Next, the operation of the transmitter 101 or the receiver 202 of the sixth embodiment will be described with reference to FIG.

FIG. 9 is a flowchart illustrating the operation of the receiver according to the sixth embodiment.

In the first embodiment, when the power of the receiver is cut off (when the battery is removed) or when the battery is removed to replace the battery of the transmitter, the electric power of the receiver or the transmitter is not changed. Since the elapsed time is erased and an error occurs in each count value of the receiver and the transmitter, unlocking may not be performed beyond the expected range of the count value. Therefore, the sixth
In the embodiment, while receiving the unlock signal that does not need to operate the transmitter, either the lock or unlock signal transmitted by the operation key of the transmitter is received, and the respective count values are correctly increased. If so, it considers it to be a legitimate transmitter so that it can be unlocked.

Specifically, as shown in FIG. 9, in step S61, a transmission code is received. In step S62, it is determined whether a lock or unlock signal has been received.

If a lock or unlock signal is received in step S62 (YES in step S62), the flow advances to step S63. If a lock or unlock signal is not received (NO in step S62), step S61 is performed.
Return to

In step S63, the transmission code is inversely converted to restore the ID code and the count value. Step S6
In step 4, it is determined whether the ID codes match. If the ID codes match in step S64 (step S6
If the ID code does not match (NO in step S64), the process proceeds to step S61.
Return to

In the step S65, it is determined whether or not the reception is the first reception after the lock. If it is not the first reception after locking in step S65 (NO in step S65), step S65
At 66, the counter 2 is set to the current count value. If it is the first reception after locking in step S65 (step S6
In step S67, the counter 1 is set to the current count value.

In step S68, it is determined whether or not the value obtained by subtracting counter 1 from counter 2 is smaller than the allowable value. If the subtraction value of the counters 1 and 2 is less than the allowable value in step S68 (YES in step S68), the process proceeds to step S69, and if the count value is not less than the allowable value (step S68).
(NO at 68), the process proceeds to step S70.

In step S69, the timer value and the count value are updated.

In step S70, the value of counter 1 is set to the value of counter 2.

According to the sixth embodiment, if the count value has been correctly increased after receiving the lock or unlock signal, the timer value and the count value are updated, so that the correct count value can be predicted and the lock can be reliably performed. And an unlock operation. [Operation of Receiver of Seventh Embodiment] Next, the operation of the transmitter 101 or the receiver 202 of the seventh embodiment will be described with reference to FIG.

FIG. 10 is a flowchart for explaining the operation of the receiver according to the seventh embodiment.

In the seventh embodiment, a counter to be transmitted by a switch operation of the transmitter and a counter which does not need to operate the transmitter are separately set, and when transmitting by a switch operation of the transmitter, a switch of the transmitter is set. Send count values that do not require operation at the same time. If the count value transmitted by the switch operation of the transmitter is correct, the count value and the timer value transmitted without any operation having an error are updated, and the normal unlock can be executed from the next reception. I have to.

Specifically, as shown in FIG. 10, in step S71, a transmission code is received. In step S72, it is determined whether a lock or unlock signal has been received.

If a lock or unlock signal is received in step S72 (YES in step S72), the flow advances to step S73. If a lock or unlock signal is not received (NO in step S72), step S71 is performed.
Return to

In step S73, the transmission code is inversely converted, and the ID code and the count value of the counter B are restored.
The value of the counter B is a count value transmitted by a switch operation of the transmitter. In step S74, it is determined whether the ID codes match. If the ID codes match in step S74 (YES in step S74), the process proceeds to step S75. If the ID codes do not match (NO in step S74), the process returns to step S71.

In the step S75, it is determined whether or not the reception is the first reception after the lock. If it is not the first reception after locking in step S75 (NO in step S75), step S75
At 76, the counter 2 is set to the current count value of the counter B. If it is the first reception after locking in step S75 (YES in step S75), counter 1 is set to the current count value of counter B in step S77.

In step S78, it is determined whether or not the value obtained by subtracting counter 1 from counter 2 is smaller than an allowable value. If the subtraction value of the counters 1 and 2 is less than the allowable value in step S78 (YES in step S78), the process proceeds to step S79, and if the count value is not less than the allowable value (step S78).
(NO at 78), the process proceeds to step S80.

In step S79, the timer value and the count value transmitted without operation are updated.

In step S80, the value of counter 1 is set to the value of counter 2.

According to the seventh embodiment, the count value of the counter B, which is transmitted by the switch operation after receiving the lock or unlock signal, is transmitted at the same time, and if the count value is correct, the non-operation Since the timer value and the count value transmitted in step (1) are updated, the correct count value can be predicted, and the locking and unlocking operations can be executed reliably. [Operation of Receiver of Eighth Embodiment] As an eighth embodiment, a sub power supply that operates when the main power supply is cut off is provided for both the receiver and the transmitter, and the respective electric time lapses are controlled by the sub power supply. Hold.

Thus, it is possible to solve the problem that the electric time lapses generated when the main power supply is cut off in the first embodiment do not match. [Operation of Transmitter of Ninth Embodiment] Next, the operation of the transmitter 101 of the ninth embodiment will be described with reference to FIG.

FIG. 11 is a diagram of a tilt switch mounted on a transmitter 101 according to the ninth embodiment.

In the sixth and seventh embodiments, since the transmitter continuously transmits the transmission code, the transmitter always consumes power. For this reason, it is necessary to frequently change batteries.
Therefore, in the ninth embodiment, the transmitter incorporates one or more tilt switches shown in FIG. 11, and detects a change in the tilt of the transmitter to operate the transmitter. That is, if the inclination does not change for a predetermined time, the transmission is stopped, and the CPU is also switched to a power saving mode such as a sleep mode to reduce the power consumption.

The tilt switch is, as shown in FIG.
The inclination in four directions of D is 40 + 15 / -10 with respect to gravity.
° can be detected. It also has four contacts A1 to D1, A1 and B1 are connected in the direction A, and B1 and D1 are connected in the direction B.
Are connected, C1 and D1 are connected in the C direction, and A1 is connected in the D direction.
And C1 are respectively connected to detect the inclination. [Operation of the receiver according to the tenth embodiment] In the conventional system, locking is performed when the received radio wave is weak (when the vehicle is separated from the vehicle). In some cases, it may be necessary to confirm by approaching the vehicle or to lock by operating a switch, and the locking may not be performed smoothly.

For this reason, in the tenth embodiment, when the ignition switch is turned off from on while the inoperative unlock signal is being received, and the door switch detects that the door is closed → open → closed, the operation is performed. Then, it is determined that the driver is about to leave the vehicle by turning off the engine and the vehicle is locked. Even if the engine key is locked while inserted, it can be unlocked by the transmitter, so there is no need to worry about the key being locked.

The present invention has been described without departing from the spirit thereof.
The above embodiment is applicable to a modified or modified embodiment.

For example, the first embodiment and the third embodiment can be combined.

A plurality of ID codes can be registered and can be changed.

Further, in the present embodiment, the communication between the transmitter 101 and the receiver 202 is wireless communication, but it is not limited to this, and it goes without saying that communication using infrared rays may be used. .

The object of remote control by the transmitter is not limited to locking and unlocking the door of the vehicle, and it goes without saying that the engine of the vehicle may be started and stopped.

[0096]

As described above, according to the present invention,
The transmission code continuously transmitted from the transmitter is converted by the rolling code method, so that the security can be improved and the locking and unlocking operations can be reliably performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a keyless entry system according to an embodiment.

FIG. 2 is a block diagram illustrating a transmitter according to the embodiment.

FIG. 3 is a block diagram illustrating a receiver according to the embodiment;

FIG. 4 is a flowchart illustrating an operation of the receiver according to the first embodiment.

FIG. 5 is a flowchart illustrating an operation of the receiver according to the second embodiment.

FIG. 6 is a flowchart illustrating an operation of a transmitter according to a third embodiment.

FIG. 7 is a flowchart illustrating an operation of the receiver according to the fourth embodiment.

FIG. 8 is a flowchart illustrating an operation of the receiver according to the fifth embodiment.

FIG. 9 is a flowchart illustrating an operation of the receiver according to the sixth embodiment.

FIG. 10 is a flowchart illustrating an operation of the receiver according to the seventh embodiment.

FIG. 11 is a diagram of a tilt switch mounted on a transmitter 101 according to a ninth embodiment.

[Explanation of symbols]

 101 Transmitter 102, 201 Antenna 200 Car 202 Receiver 103, 204 EEPROM 105, 207 Microcomputer 106, 209 Reset circuit 107 Battery 108, 212 Timer 203 Door lock control unit (DCU) 208 Power supply circuit 210 Signal receiving circuit

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsutoshi Isaka 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima N-Dec F-term (reference) 2E250 AA21 BB08 BB35 CC06 DD06 EE10 FF23 FF24 FF36 FF38 HH01 JJ02 JJ03 KK03 LL00 LL01 TT03

Claims (10)

[Claims] A transmitting means for converting identification information including the number of transmissions and transmitting the information at predetermined time intervals; and restoring the identification information received from the transmitting means, wherein the number of transmissions is within a predetermined regulation value. Receiving means for determining whether or not the identification information is legitimate; and an unlocking device for unlocking the locking means based on the determination result of the receiving means, wherein the receiving means measures a reception interval of the identification information. A timer for performing the operation, the identification information is valid, and the number of transmissions included in the identification information is predicted based on the result of the measurement by the timer. If the number of transmissions is within the prediction range, the locking unit is unlocked. An unlocking device characterized in that the unlocking device is operated. 2. The unlocking device according to claim 1, wherein the number of transmissions predicted by the receiving means is updated when a predetermined condition is satisfied. 3. The unlocking device according to claim 2, wherein the predetermined condition is a state in which legitimate identification information can be received after the engine is started. 4. The unlocking device according to claim 2, wherein the predetermined condition is a state in which valid identification information after stopping the engine can be received. 5. The transmitting means includes an operation key for transmitting operation information for operating unlocking or locking separately from the identification information, and the receiving means transmits the operation information while receiving the identification information. 2. The unlocking device according to claim 1, wherein, when receiving, if the number of transmissions is within a prediction range, the locking unit is unlocked. 6. The transmitting means simultaneously transmits the number of transmissions of the identification information when transmitting the operation information, and the receiving means transmits the number of transmissions of the operation information when receiving the operation information. 2. The unlocking device according to claim 1, wherein if the is normal, the number of times of transmission of the identification information predicted by the receiving means is updated. 7. The transmission means and the reception means include a storage means for storing the number of times of transmission of the identification information and the number of times of transmission of operation information, and the storage means is backed up by a sub power supply. The unlocking device according to claim 1, wherein: 8. The unlocking device according to claim 1, wherein the transmitting unit includes a switch that operates based on a change in the state of the transmitting unit. 9. A transmitting means for converting identification information and transmitting the converted information at predetermined time intervals, and a receiving means for restoring the identification information received from the transmitting means and determining whether or not the identification information is legitimate. An unlocking device for unlocking the locking means when the identification information is legitimate and the legitimate identification information is correctly received a plurality of times. 10. A transmitting means for converting identification information including the number of transmissions and transmitting the information at predetermined time intervals, and restoring the identification information received from the transmitting means so that the number of transmissions is within a predetermined regulation value. A receiving unit that determines whether the identification information is legitimate; and an unlocking device that unlocks the locking unit based on a determination result of the receiving unit. An unlocking device characterized in that it counts every time it is done.