JPH0443562Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a code that can unlock a door using an encryption code, and that the shorter the time elapsed since the door was locked, the fewer the number of digits of the encryption code required to unlock the door. This invention relates to a door lock release device that takes shortening measures, and is intended to reduce the probability of theft by canceling the code shortening measures, especially when an incorrect code code is input.

[Conventional technology]

A device that can unlock a door by inputting a code code from the outside is useful because it allows the door to be opened without a key, such as when the door is accidentally locked while the key is left inside the car. It is desirable for this type of code to be long (with a large number of digits) from the perspective of preventing theft, but it is more convenient for the user to operate it if it is short.

In order to satisfy these conflicting demands, if the time elapsed since the door was locked is short, the number of digits required to unlock the door is reduced based on the assumption that the risk of theft is low, such as when the user is nearby. There is a method in which the number of digits required for unlocking is gradually increased, considering that the risk of theft increases as the elapsed time increases.
For example, when using a 4-digit code, the first digit can be used to unlock the door for up to 10 minutes, then 2 digits for 30 minutes, 3 digits for 60 minutes, and any more. This requires input of all digits.

[Problem that the invention attempts to solve]

However, if the door is stolen while the above-mentioned code shortening measures are being taken, the door lock is more likely to be unlocked due to the small number of digits. The present invention attempts to further improve this point.

[Means for solving problems]

The present invention is equipped with a control unit that unlocks the door when a multi-digit code stored in memory matches a code input from the outside, and also shortens the time elapsed since the door is locked by shortening the code. In a door lock release device that reduces the number of digits required for an encryption code for matching, when the control unit detects an error in the encryption code input from the outside, it cancels the encryption code shortening measure and erases all digits. This method is characterized in that it shifts to matching verification.

[Effect]

A legitimate user has a high probability of correctly inputting the encryption code for unlocking, but those attempting to steal the code generally do not know the encryption code at all and repeat trial and error. Therefore, if an error is detected in the encryption code input and the encryption code shortening measure is canceled thereafter, it is possible to substantially prevent an increase in the probability of theft due to the encryption code shortening measure. Moreover, since authorized users can benefit from the shortened encryption code, the ease of operation is not reduced.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, in which 1 is a code input switch, 2 is a door lock detection switch, 3 is a control unit, 4 is a door lock release mechanism, and 5 is a battery. The control unit 3 includes an input interface 6, a logic operation section 7, an output interface 8, a timer 9, and a power supply section 10. The logic operation section 7 is a microprocessor, the general flow of which is shown in FIG. "start"
is when the battery 5 is connected, "input" is the input processing of the switches 1 and 2, and "output" is the processing when the door lock is released. "Switching the number of digits" in between
The details of each process of "encryption code determination" are shown in FIGS. 3 and 4.

The logic operation unit 7 starts incrementing the timer 9 when the switch 2 detects the door lock according to the flow shown in FIG. Even if the number of digits of the code stored in the memory is 4, only the first digit is subject to matching until time _T1 has elapsed since the door lock (the 2nd to 4th digits are ignored). do). Even after T ₁ has elapsed, only the first and second digits of the encryption code are subject to verification until T ₂ . And T ₃
The 1st to 3rd digits are subject to verification until the elapsed time, but T ₃
After the lapse of time, all digits are subject to verification. This is a normal encryption code shortening measure, and T ₁ , T ₂ , and T ₃ correspond to 10 minutes, 30 minutes, and 60 minutes in the above example.

The process shown in the second half of FIG. 4 cancels this encryption code shortening measure. The first half of the figure shows the matching of the encryption code, with OK flags FOK1 to FOK1 corresponding to each digit.
Use FOK4. All of these flags remain 0 when there is no code input, but when there is a code input, the digits are determined and each digit is compared with the set value in the memory. This is the "code OK" process. If they match, the corresponding OK flag is set to 1.

As shown in FIG. 3, the required number of cipher digits changes over time depending on the elapsed time after the door is locked, and if the number of cipher digits is 1, the door lock is released by just FOK=1. However, even if there is a code input immediately after the door is locked (before _T1 elapses), if FOK=0 (unmatched), the timer is forcibly set to _T3 . As a result, the number of cipher digits increases to 4 according to the flow shown in FIG. 3, so that the door lock cannot be released unless all digits match. If T ₁ has elapsed but T ₂ has not elapsed, the number of cipher digits is 2. In this case, the first and second digits must both match, so FOK1=1 and FOK2=1 are the conditions for unlocking the door. In this case, if at least one of them is a mismatch, the timer is still forced to _T3 .
Then, all FOK1 to FOK4 are returned to 0 and the process ends.
The same applies hereafter.

The code input switch 1 is, for example, a switch linked to a handle for opening and closing a door, and the code code is input by dividing a serial pulse train into digits. The encryption code in the memory is set in advance, but it is entered in the setting mode using the same switch. However, these can be modified in various ways.

[Effect of idea]

As described above, according to the present invention, from the viewpoint of preventing theft and simplifying regular use, the door unlocking device that changes the required number of digits of the code code required for unlocking the door depending on the time elapsed after the door is locked is used. There is an advantage that the prevention function can be strengthened without impairing the ease of regular use.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention.
Figure 2 is a general flowchart showing the general operation, Figure 3 is a flowchart for switching the number of digits,
FIG. 4 is a flowchart of cryptographic code determination. In the figure, 1 is an encryption code input switch, 2 is a door lock detection switch, 3 is a control unit, 4 is a door lock release mechanism, 7 is a logic operation unit, and 9 is a timer.

Claims (1)

[Scope of utility model registration request] Equipped with a control unit that releases the door lock when a multi-digit code written in the memory matches a code input from the outside, and also uses code shortening measures to increase the chance of matching as the time elapses from the time the door is locked. In a door lock release device that reduces the number of required digits of the required encryption code, when the control unit detects an error in the encryption code input from the outside, it cancels the encryption code reduction measure and matches all digits. A door lock release device characterized in that it is a door lock release device.