JPH0949352A - Key device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a key device and reduce the cost by removably forming a key blank and a hold section provided with a rewritable transmitting/receiving means. SOLUTION: When a key 1 is inserted into a key cylinder and turned to the on-position, radio signals are exchanged, and the code signal sent from the key 1 side is collated with the collation code stored on a vehicle side in advance. When both codes coincide, the key 1 is judged to be a regular key, and an engine is made operable. A key cylinder coil 6 is provided to surround the inlet end side of the key hole 3a of the key cylinder 3, and a transponder 7 serving as a transmitting means is provided on a key hold section 5. A key blank and the key hold section 5 are separately formed, the key 1 can be set to the rewritable state only when it is intentionally operated to integrate them, and it can be prevented from being unnecessarily set to the rewritable state when a user uses it by mistake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key device,
In particular, the present invention relates to a key device configured to exchange signals between the key side and the key cylinder side so as to prevent the use of a duplicate key.

[0002]

2. Description of the Related Art Conventionally, various anti-theft devices for automobiles have been proposed. For example, as disclosed in Japanese Examined Patent Publication No. 4-15141, a key for operating an ignition switch and a vehicle body side are provided. A coil is provided on each of the key cylinder and the key cylinder, and when a key is inserted into the key cylinder, a magnetic circuit is formed between the coils, and an electric signal composed of a first unique code is transmitted from the key side. Is received by the key cylinder side, and this code is collated with the first collation code stored in the key cylinder side receiver to determine whether or not the key is legitimate, so-called immobilizer. The system is known.

In the immobilizer system, for example, when the key is lost, the first collation code stored in the receiver on the key cylinder side can be rewritten so that the lost key is not misused. When the newly stored code signal is received, that is, only the key that transmits the newly set first unique code signal must be changed so that it can be determined as a regular key.

In practice, the following can be done. That is, in addition to the normal key, a rewriting key is prepared in which a transmitter that can transmit a second unique code different from the first unique code is provided in the grip portion. Further, the receiver stores a second collation code different from the first collation code. Then, the rewriting key is inserted into the key cylinder, the second unique code is transmitted / received, and the second collation code is collated.
The collation code of will be rewritable mode. In this state, the rewriting key is removed, a key capable of transmitting a signal including the new first unique code is inserted into the key cylinder, and the signal is exchanged, whereby the new first unique code is stored as a new first collation code. To be done. After that, only the key transmitting the electric signal including the new first unique code is determined to be the regular key.

[0005]

In the above structure,
Since the rewrite key performs the same operation as a normal key operation, it is necessary to have a grip portion provided with a transmitter and a key blank as in the normal key. However, since this rewrite key is not used unless there are special circumstances such as loss of the key, it is generally not used at all, and the structure should be simplified as much as possible to reduce the cost. Is desired.

The present invention has been devised in order to solve the above problems of the prior art, and its main purpose is to:
It is to simplify the structure of a key device that employs an immobilizer system and reduce the cost thereof.

[0007]

According to the present invention, when a key is inserted into a key cylinder, a transmitting / receiving means provided in the key transmits a radio signal including a first unique code. Then, the key cylinder side transmitting / receiving means receives this, and collates it with the first collating code which is stored in the transmitting / receiving means side in advance and is rewritable from the outside to determine whether or not the key is a regular key. A rewrite key having a second transmitting / receiving means for transmitting a radio signal including a second unique code is inserted into the key cylinder to transmit the radio signal including the second unique code. Then, the signal is received by the transmitting / receiving means on the key cylinder side and is collated with the second collating code stored in advance on the transmitting / receiving means side to rewrite the first collating code. In a key device that is in a ready state, the rewriting key includes a grip portion provided with the second transmission / reception means and a key blank, and the grip portion and the key blank are detachable. It is achieved by providing a key device characterized in that

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a front view showing a main part of an automobile key device to which the present invention is applied. In Figure 1, key 1
Is a key cylinder 3 provided on the steering column 2 and configured to operate an ignition switch.
The key blank 4 is inserted into the key hole 3a, and the grip portion 5 is formed by insert-molding the widened portion 4a integrally formed at one end of the key blank 4.

The key cylinder 3 is, like a known automobile ignition switch, a "LOCK" position for fixing the steering wheel, an "OFF" position in which the ignition is off, and an "ACC" for activating a part of the vehicle-mounted device. Position, the "ON" position for turning on the ignition switch, and the "S" for driving the starter motor.
The "T" position is set, and is connected to a mechanical contact that opens and closes according to the rotational position of the key 1 and a lock mechanism that engages with the steering shaft.

In this key device, the key 1 is attached to the key cylinder 3.
When a key is inserted and turned to the "ON" position, a radio signal is transmitted and received between the key cylinder 3 and the key 1, and a code signal composed of a first unique code issued from the key 1 side is stored in the vehicle side in advance. It is configured to match the first matching code that is present, and if the codes match each other, the key is determined to be a valid key and the engine is made operable. As a means therefor, a key cylinder side coil 6 is provided so as to surround the entrance end side of the key hole 3a of the key cylinder 3, and a first and second electromagnetic wave signal is exchanged with the key cylinder side coil 6. A transponder 7 as a transmitting / receiving means for the key 1 is provided in the grip portion 5 of the key 1.

Transponder 7 provided on the key 1 side
2, as shown in FIG. 2, the antenna 7a as the key side coil, the transmission / reception circuit 7b electrically connected to the antenna 7a, and the IC chip 7 connected to the transmission / reception circuit 7b.
c and is received in the inside of a glass tube whose both ends are rounded and which is closed. A controller 8 is connected to the key cylinder side coil 6 provided on the vehicle body side. Inside the controller 8, a transmitter / receiver circuit 8a electrically connected to the key cylinder side coil 6 and a transmitter / receiver circuit 8a. A control circuit 8b connected to the control circuit 8b and a memory circuit 8c connected to the control circuit 8b are provided. In this memory circuit 8c, a rewritable first collation code and a second rewritable prohibited collation code, which will be described later, are stored. Further, the control circuit 8b is connected to an ON position detection switch SW that is interlocked with the key cylinder 3.

In the key device thus constructed, when the key blank 4 is inserted into the key hole 3a of the key cylinder 3 and is rotated to the "ON" position, the ON position detection switch SW is closed. Is detected by the control circuit 8b, the controller 8 is activated, and radio waves are transmitted from the key cylinder side coil 6 via the transmission / reception circuit 8a. When the antenna 7a in the transponder 7 receives this radio wave, electromotive force is generated in the antenna 7a by the electromagnetic induction effect. This electric power is converted into direct current and the transmitting / receiving circuit 7b
And IC chip 7c to drive both circuits 7b and 7c. Then, a radio signal including the first unique code stored in advance in the IC chip 7c is transmitted from the antenna 7a.

When the code signal transmitted from the antenna 7a is received by the coil 6 on the key cylinder side, it is input to the control circuit 8b via the transmission / reception circuit 8a. The control circuit 8b has a first collation code stored in advance in the memory circuit 8c,
The code signal from the antenna 7a is compared and collated. When the first unique code and the first collation code match, the controller 8 outputs a permission signal to an engine control circuit (not shown) to enable the engine to operate. The engine control circuit has a function of turning on the starter circuit, the fuel circuit, the ignition circuit, and the like.

If the codes do not match, the engine is not operated. In addition, the engine operable state may be valid until at least the key 1 is removed,
The key 1 may be held for a certain period of time after being removed, or it may be held until the door is locked and the door is locked. By doing so, it is not necessary to perform the code comparison and verification process again when the key 1 is removed and then restarted, which is effective for power saving.

On the other hand, as shown in FIG. 3, in addition to the key 1, a rewritable gripping unit 11 unique to each key device is facilitated in the key device. The rewritable gripping unit 11 can be selectively engaged with a key blank 14 similar to the key blank 4 of the key 1,
Engagement protrusions 11a and 11b that elastically engage with the holes 15 and 16 of the widened portion 14a are provided. Further, a transponder 17 as a second transmitting / receiving means for rewriting is embedded in one of the engaging protrusions 11a so as to be located on the axis of the key. The rewriting transponder 17 stores a second unique code corresponding to the second collation code stored in the memory circuit 8c of the key cylinder side controller 8.

The first data stored in the memory circuit 8c of the key cylinder side controller 8 due to the loss of the key 1 or the like.
When rewriting the verification code of No. 1 to correspond to the new first unique code stored in the new key, first, prepare the key blank 14 that fits the key cylinder 3 and engage with the grip unit 11 for rewriting. Let And
The key hole 3a of the key cylinder 3 is the same as the normal collation operation.
The key blank 14 is inserted into and is rotated to transmit a radio wave signal including the second unique code. When the key cylinder side coil 6 receives this, it is input to the control circuit 8b via the transmission / reception circuit 8a. The control circuit 8b is the memory circuit 8
The second collation code previously stored in c and the code signal from the antenna 7a are compared and collated. When the second unique code and the second collation code match, the first collation code stored in the memory circuit 8c becomes rewritable for a predetermined time. In this state, the key blank 14 is taken out, and a new key 1 is used to send and receive a signal consisting of a new first unique code, whereby this new first unique code is stored in the memory circuit 8c as a new first collation code. It From then on, the engine can be started only by matching the new code and the mechanical key.

In practice, whether the first unique code or the second unique code is transmitted when the key blank 4 or 14 is inserted into the key cylinder 3 depends on, for example, a certain unique code. It may be judged by the bit at the digit position, and if it does not match the first collation code every time, the second
You may make it collate with the collation code of.

FIG. 4 is a perspective view showing another example of an automobile key device to which the present invention is applied. In this example, an axial direction through hole 21a for inserting the key blank 14 into the grip unit 21 is formed. This axial through hole 21a
Has a narrower tip side opening than the base side opening,
The inserted key blank 14 is designed not to fall out. A transponder 17 as a second transmitting / receiving means for transmitting an electric signal composed of a second unique code is embedded on the center line of the grip unit 21. The other structure is similar to the above-mentioned example.

[0020]

As described above, according to the present invention, the rewriting key is composed of the grip portion provided with the transmission / reception means for rewriting and the key blank, and the grip portion and the key blank can be freely attached and detached. This simplifies the structure of the key device and reduces its cost. Further, since the grip portion has a verification code unique to the vehicle, it is necessary to hand it over to the user in advance. Since it can be given to the user together with the new key having the collation code, the initial cost burden on the user can be reduced.
Furthermore, since the key blank and the gripping part are usually separated from each other, the key blank and the grip part can be rewritable only when a conscious operation of combining them is performed, and the user does not need to use them by mistake and does not need them. However, it will not be rewritable.

[Brief description of drawings]

FIG. 1 is a front view of a main part of a key device to which the present invention has been applied, partially broken away.

FIG. 2 is a schematic circuit diagram of a key device to which the present invention is applied.

FIG. 3 is a perspective view of an essential part of a code rewriting gripping unit prepared for the key device shown in FIGS. 1 and 2 and a key blank attached to the gripping unit.

FIG. 4 is a perspective view of an essential part of a code rewriting gripping unit similar to FIG. 3 and a key blank attached to the same, showing another embodiment of the key device to which the present invention is applied.

[Explanation of symbols]

 1 Key 2 Steering Column 3 Ignition Key Cylinder 3a Key Hole 4 Key Blank 4a Key Blank 5 Grip Part 6 Key Cylinder Side Coil 7 Transponder 7a Antenna (Key Side Coil) 7b Transmitter / Receiver Circuit 7c IC Chip 8 Controller 8a Transmitter / Receiver Circuit 8b Control Circuit 8c Memory circuit 11 Grip unit 11a, 11b Engagement projection 14 Key blank 15, 16 hole 17 Transponder 21 Grip unit 21a Axial direction through hole

Claims (1)

[Claims] 1. When a key is inserted into a key cylinder, a transmitting / receiving means provided in the key transmits a radio wave signal consisting of a first unique code, and the transmitting / receiving means on the key cylinder side receives and transmits the radio signal. By comparing with a first collating code which is stored in advance on the means side and which can be rewritten from the outside, it is determined whether or not the key is a regular key, and a radio wave including a second unique code. A rewriting key having a second transmitting / receiving means for transmitting a signal is inserted into the key cylinder to transmit a radio wave signal including the second unique code, and the signal is received by the transmitting / receiving means on the key cylinder side. A key device that puts the first collation code into a rewritable state by collating with a second collation code stored in advance on the transmitting / receiving means side. Chromatography is, the second receiving means is composed of a grip portion and a key blank provided, the key device characterized by said gripping portion and said key blank is detachable.