JP2001262878A - Key and discrimination device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key and a discrimination device therefor ensuring specific strength by integrally forming the whole body including a hold section of a metal plate and, at the same time, extending the maximum operating distance of a transponder without enlarging the hold section larger than it needs. SOLUTION: A through-hole 13a is formed in the metal plate-like hold section 13, a notch section 13b is formed in the circumferential edge of the through-hole 13a, and the transponder 16 is stored in the through-hole 13a. The transponder 16 includes an antenna coil 17 and an IC chip 18 storing inherent information of a key 11 electrically connected to the antenna coil 17. The axis of the antenna coil 17 is so constituted that it is vertical to the surface of the hold section 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hard-to-counterfeit key having a transponder. Further, the present invention relates to an identification device for identifying a legitimate key and a forged key.

[0002]

2. Description of the Related Art Conventionally, a key cylinder and a key are provided with a key cylinder side signal transmission / reception means and a key side signal transmission / reception means, respectively. When a key is inserted into the key cylinder, transmission and reception of a radio signal between the two signal transmission / reception means are performed. A key device for determining whether a key is a legitimate key is disclosed (Japanese Patent Laid-Open No. Hei 7-279509). In this key device, the key-side signal transmission / reception means (transponder) is housed in a holding member made of synthetic resin, and the holding member is arranged on a holding portion of a metal key. The transponder also has a key-side coil and an IC chip electrically connected to the coil via a transmission / reception circuit. In the key device configured as described above, since the key-side signal transmitting / receiving means is protected by the holding member, the stress applied to the key-side signal transmitting / receiving means can be reduced, and the strength of the entire key can be improved. Further, since it is only necessary to dispose the holding member accommodating the key-side signal transmitting / receiving means on the grip portion, the assembling work of the key-side signal transmitting / receiving means with respect to the keys can be improved.

[0003]

However, in the above-described key device disclosed in Japanese Patent Application Laid-Open No. 7-279509,
In order to prevent the inductance of the key side coil from being affected by the metal gripping part, it is necessary to provide a sufficiently large space between the key side coil and the gripping part. there were. If the size of the key-side coil is reduced to solve this problem, there is a problem that the maximum operating distance of the transponder becomes short. An object of the present invention is to secure a predetermined strength by integrally forming the entirety including a grip portion with a metal plate,
It is an object of the present invention to provide a key capable of extending a maximum operation distance of a transponder without making a grip part unnecessarily large. Another object of the present invention is to provide a key identification device capable of preventing starting or unlocking by a forged key and automatically recording locking and unlocking by a legitimate key. .

[0004]

The invention according to claim 1 is
As shown in FIG. 1, a through-hole 13a formed in a metal plate-like gripper 13, a notch 13b formed in the periphery of the through-hole 13a, and a transponder 16 accommodated in the through-hole 13a.
A transponder 16 having an antenna coil 17 and an IC chip 18 electrically connected to the antenna coil 17 and storing information unique to the key 11, wherein the axis of the antenna coil 17 is It is characterized in that it is configured to be perpendicular to the surface of the portion 13. In the key according to the first aspect, the entire key 11 including the plate-shaped grip portion 13 is integrally formed of a metal plate.
A predetermined strength that can withstand use as the key 11 can be secured. When the antenna coil 17 receives a radio wave, the cutout 13b formed in the plate-shaped grip 13 causes an eddy current in the grip 13 around the through hole 13a (generated in a direction to cancel the radio wave). Does not occur, the antenna coil 17 receives the radio wave efficiently. As a result, the operating maximum distance of the transponder 16 can be extended without making the grip portion 13 unnecessarily large.

As shown in FIG. 6, a transponder 66 is provided on the surface of a metal plate-shaped grip 63 as shown in FIG.
, A transponder 66 has an antenna coil 67 and an IC chip 18 electrically connected to the antenna coil 67 and storing information unique to the key 61. The antenna coil 67 is a magnetic core member. 67a and a coil portion 67b wound around the magnetic core member 67a, and is characterized in that the axis of the antenna coil 67a is parallel to the surface of the grip portion 63. In the key described in claim 2, since the antenna coil 67 receives a radio wave parallel to the grip 63, the radio wave is only slightly affected by the metal grip 63, and the antenna coil 67 The radio waves can be received efficiently, and the maximum operating distance of the transponder 66 can be extended. Further, since the radio wave transmitted from the transponder 66 is also parallel to the grip 63, the influence of the grip 63 is small.

According to a third aspect of the present invention, as shown in FIG. 8, a concave portion 83 formed on the surface of a metal plate-shaped grip portion 83 is provided.
and a transponder 66 housed in the recess 83a. The transponder 66 includes an antenna coil 67 and an IC chip 18 electrically connected to the antenna coil 67 and storing information unique to the key 81. Has,
The antenna coil 67 includes a magnetic core member 67a and the magnetic core member 6a.
The coil portion 67b is wound around 7a so that the axis of the antenna coil 67 is parallel to the surface of the grip portion 83. In the key according to the third aspect, since the transponder 66 is housed in the concave portion 83a of the grip portion 83, the thickness of the entire key 81 can be reduced.

According to a fourth aspect of the invention, as shown in FIGS. 3 and 4, a lock 14 into which the key 11 according to any one of the first to third aspects can be inserted, and a transponder provided near the lock 14 or the lock 14 are provided. And identification means 23 for transmitting radio waves to the IC chip 18 to read information stored in the IC chip 18. The identification means 23 has a transmitting / receiving antenna 27 which interacts with the antenna coil 17. This is a key identification device configured to read information stored in the IC chip 18 via the antenna 27. Claim 4
When the key 11 is inserted into the lock 14, the radio wave transmitted from the transmitting / receiving antenna 27 is received by the antenna coil 17, and the IC chip 18 is operated by mutual induction between the transmitting / receiving antenna 27 and the antenna coil 17. Is activated, a radio wave carrying information unique to the key 11 stored in the IC chip 18 is transmitted from the antenna coil 17 and received by the transmission / reception antenna 27. As a result, the identification means 23 reads the information stored in the IC chip 18 and determines whether this information is valid key information. If the information is valid information, the key 11 inserted into the lock 14 is used. Start or unlock by operation, lock 1 if false information
Even when the key 11 inserted in the key 4 is operated, the key is not started or unlocked.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 4, the key 11 is a key body 12 inserted into a key cylinder 14 (lock).
And a plate-like grip 1 integrally formed with the key body 12.
3 is provided. It is preferable that the key body 12 and the plate-shaped grip portion 13 are manufactured in a plate shape by pressing a metal plate or casting a metal. It is preferable to use brass, bronze, bronze, stainless steel (for example, SUS304) or the like as the metal plate or cast metal (key material). It is not preferable to manufacture the key 11 from a ferromagnetic material because the loss of the antenna coil 17 described later increases. However, when the key 11 needs to be manufactured at low cost, it is preferable to use a mild steel (ferromagnetic material). A key 11 manufactured and plated on the surface may be used. A through-hole 13a is formed at the center of the plate-like gripping portion 13, and a notch 12 is formed at the periphery of the through-hole 12a.
b is formed. The notch 12 b is formed on the base end side of the grip 13. The grip 13 has a substantially T-shaped projection 1.
3c is provided so as to protrude into through-hole 13a.

The transponder 16 is accommodated in the through hole 13a. The transponder 16 is an antenna coil 17
And the key 11 electrically connected to the antenna coil 17.
And an IC chip 18 for storing unique information. The antenna coil 17 is formed in a thin donut shape by winding a covered conductor many times, and the IC chip 18 is accommodated in the center of the antenna coil 17. The transponder 16 is accommodated in the through-hole 13 a with the axis of the antenna coil 17 oriented perpendicular to the surface of the grip 13. Reference numeral 19 in FIGS. 1 and 2 denotes a resin covering member that covers the grip 13 together with the transponder 16 and fixes the transponder 16 to the grip 13.

As shown in FIG. 3, the IC chip 18 includes a power supply circuit 18a, a radio frequency (RF) circuit 18b, a modulation circuit 18c, a demodulation circuit 18d, a CPU 18e, and a unique key 11 connected to the CPU 18e. And a memory 18f for storing information. The power supply circuit 18a includes a capacitor (not shown), and the capacitor forms a resonance circuit with the antenna coil 17. When the antenna coil 17 receives a radio wave of a specific frequency (the frequency at which the resonance circuit resonates), the capacitor is charged with electric power generated by the mutual induction. The power supply circuit 18a rectifies and stabilizes the power and supplies it to the CPU 18e to activate the IC chip 18. The memory 18f is a ROM (read o)
nly memory), RAM (ramdom-access memory) and E
EPROM (electrically erasable pogramable read
under the control of the CPU 18e to read stored data in response to a read command by radio data communication from the identification means 23, which will be described later, and to read data stored in response to a write command from the identification means 23. Is written.

On the other hand, as shown in FIG.
4 is attached to the steering column 22 of the car, and the I of the transponder 16 is
An identification means 23 for reading information stored in the C chip 18 is provided. The steering column 22 is configured to rotatably hold a steering shaft 26 having a steering wheel 24 attached to an upper end. The identification means 23 includes a transmitting / receiving antenna 27 that interacts with the antenna coil 17 and a processing unit 28 that transmits radio waves from the transmitting / receiving antenna 27 and processes the radio waves received by the transmitting / receiving antenna 27 (FIG. 3).

The transmitting / receiving antenna 27 is connected to the transponder 16.
A radio wave can be transmitted to the antenna coil 17 and a radio wave from the antenna coil 17 can be received. The processing unit 28 is connected to the transmission / reception antenna 27, and includes a power supply circuit 28a containing a battery and a radio frequency (RF) circuit 28b.
, Modulation circuit 28c, demodulation circuit 28d, CPU 28
e and a memory 28f connected to the CPU 28e and storing information read from the IC chip 18. When the key 11 is inserted into the key cylinder 14, the transmission / reception antenna 27 has the axis of the antenna coil 17
7 is configured to substantially coincide with the axis. Further processing unit 2
The control output of 8 is connected to a fuel supply switch (not shown). This switch, which is not shown, turns on and off a fuel supply pump that supplies fuel from the fuel tank to the engine.

The operation of the key and the identification device configured as described above will be described. As shown in FIG.
Is inserted into the key cylinder 14, the antenna coil 17
Is substantially coincident with the axis of the transmitting / receiving antenna 27 of the identification device 23. In this state, the interrogation signal of the binary digital signal is transmitted from the transmission / reception antenna 27 to the antenna coil 17 over a radio wave of a specific frequency. The digital signal is modulated by the modulation circuit 28c, and the RF circuit 28b
And transmitted from the transmitting / receiving antenna 27. At this time, the notch 13b formed in the plate-shaped grip 13
Since no eddy current (generated in the direction to cancel the radio wave) centering on the through hole 13a is generated in the grip portion 13, and since the axis of the antenna coil 17 is substantially coincident with the axis of the transmitting / receiving antenna 27, The radio waves are efficiently received by the antenna coil 17.

When the antenna coil 17 receives the radio wave, the transmitting and receiving antenna 27 is connected to the capacitor of the power supply circuit 18a.
And the electric power generated by the mutual induction action of the antenna coil 17 is charged. The power supply circuit 18a supplies power to the CPU 18e, activates the IC chip 18, and causes the demodulation circuit 18d to reproduce the original digital signal interrogation signal via the RF circuit 18b. The CPU 18e transmits information on the key 11 stored in the memory 18f based on the inquiry signal. The transmission of this information is performed by converting the binarized data signal into an IC.
The signal is modulated by the modulation circuit 18c of the chip 18, and the RF circuit 18b
This is performed by amplifying the signal and transmitting the signal from the antenna coil 17. The transmitted data is received by the transmission / reception antenna 27 of the identification unit 23, and the processing unit 28
It is determined that the information unique to the key 11 is the information of the legitimate key 11. As a result, when the driver operates the key 11, the identification means 23 closes the fuel supply switch, so that the fuel supply pump operates and the automobile starts.

On the other hand, if the driver inserts the forged key 11 into the key cylinder 14, the identification means 23 cannot obtain the information unique to the key 11 from the key 11, so that even if the driver operates the key 11, The identification means 23 keeps the fuel supply switch open. As a result, since the fuel supply pump does not operate, the vehicle does not start and theft of the vehicle can be prevented. Since the resonance frequency of the antenna coil 17 slightly changes due to the presence of the metal gripping portion 13, the number of turns of the antenna coil 17 is set so that the resonance frequency becomes a predetermined value when the antenna coil is mounted on the gripping portion 13. Is increased, the maximum operating distance of the transponder 16 is increased. Also, if a magnetic core member (a laminated body of amorphous foil, soft ferrite, powder of magnetic material or composite material of flake and insulating material, etc.) is inserted into the center of the antenna coil,
The working maximum distance is further extended.

Further, a lock which is locked or unlocked using the key of the present invention is incorporated in a safe, locker, house or the like, and the identification means for reading the information (ID) stored in the transponder of the key is provided by the safe, locker. The lock may be an electric lock which is not unlocked unless the information of the transponder matches the information (ID) stored in the identification means. As a result, unauthorized unlocking by the forged key can be prevented. If the information (ID) is unlocked by a key that does not match, the identification means emits an alarm sound and informs a security company, a guardhouse, etc., so that theft can be prevented.

FIG. 5 shows a second embodiment of the present invention.
5, the same reference numerals as those in FIGS. 1 and 4 denote the same parts. In this embodiment, the key 11 is a key for locking or unlocking the door 42. That is, the key cylinder 44 can be switched between a locked state (locked) and an unlocked state (unlocked) by inserting and operating the key 11 in the key cylinder 44 (lock). The key 11 is configured in the same manner as in the first embodiment, and a transponder 16 having an antenna coil 17 and an IC chip 18 is accommodated in a through hole (not shown) of the plate-like grip 13. Also, many employees can enter and leave the room inside the door 42, and each of these employees is configured to have the key 11 whose name and the like are stored in the memory of the IC chip 18. . On the other hand, the door 42 is formed of metal,
The identification means 43 is fixed to the outer surface of the second member 2. The identification means 43 includes a transmission / reception antenna 47 having a plate-shaped magnetic core member 47a,
Except for having a coil portion 47b wound around the magnetic core member 47a, the configuration is the same as that of the identification means of the first embodiment.

As the magnetic core member 47a, a laminated body of amorphous foil, soft ferrite, powder of magnetic material or composite material of flake and insulating material, etc. are used. Examples of the magnetic material of the composite material include iron, permalloy, an iron-cobalt alloy, an amorphous magnetic material, and ferrite. These magnetic materials are powdered by a chemical method such as an atomizing method or a reduction method, or a pulverization method, or the powder is further flattened by a ball mill or the like to form flakes,
Alternatively, it is preferable to make a flake by colliding a molten metal of a magnetic material with a wall surface. When the content of the magnetic material is increased to increase the magnetic permeability of the magnetic core member 22a, the surface of the powder or the surface of the flakes of the magnetic material is reduced to prevent direct contact between the powders of the magnetic material or the flakes. It is preferable to coat with an insulating material such as a phosphoric acid compound, glass, and resin. Except for the above, the configuration is the same as that of the first embodiment.

The operation of the key and the identification device configured as described above will be described. When an employee inserts the key 11 into the key cylinder 44 of the door 42, the axis of the antenna coil 17 substantially matches the axis of the transmitting / receiving antenna 47 of the identification device 43. In this state, as in the first embodiment, the antenna coil 1 of the transponder 16 is
An interrogation signal of a digital signal binarized toward 7 is transmitted on a radio wave of a specific frequency. At this time, the notch formed in the plate-shaped grip portion 13 causes the grip portion 13 to have an eddy current centered on a through hole (generated in a direction to cancel the radio wave).
Does not occur, and since the axis of the antenna coil 17 is substantially coincident with the axis of the transmitting / receiving antenna 47, the radio wave is efficiently received by the antenna coil 17.

When the antenna coil 22 receives the radio wave, the capacitor of the power supply circuit is charged with the electric power generated by the mutual induction between the transmitting / receiving antenna 47 and the antenna coil 17 as in the first embodiment. Power supply circuit uses CPU power
The IC chip 18 is activated, and the interrogation signal of the original digital signal is reproduced by the demodulation circuit via the RF circuit. The CPU transmits information on the key 11 stored in the memory based on the inquiry signal. To transmit this information, the binarized data signal is modulated by the modulation circuit of the IC chip 18, amplified by the RF circuit, and amplified by the antenna coil 17.
This is done by sending from The transmitted data is received by the transmission / reception antenna 47 of the identification means 43,
Numeral 8 stores information unique to the key 11 from the transponder 16 (name of a predetermined employee, date and time of entering the room, etc.) in a memory. In addition, the employee inserts the key 11 inserted in the key cylinder 44.
Is operated to lock or unlock. As a result, when each employee enters or leaves the room, it is possible to reliably and accurately obtain the information of the identification means 43 without having to perform the troublesome work of recording the name and date and time of the person who unlocked or locked the room. Since the information is automatically stored in the memory, it is possible to prevent forgetting to record and writing incorrect information.

FIGS. 6 and 7 show a third embodiment of the present invention. 6 and 7, the same reference numerals as those in FIGS. 1 and 2 indicate the same parts. In this embodiment, the transponder 66 is attached to the surface of the plate-like grip 63 of the key 61. In this case, no through-hole is formed in the grip portion 63. The antenna coil 67 includes a magnetic core member 67a and a coil portion 67b wound around the magnetic core member 67a. The axis of the antenna coil 67 (the longitudinal direction of the magnetic core member 67a) is parallel to the surface of the grip portion 63. It is configured to be. The magnetic core member 67a is made of the same material as the magnetic core member of the transmitting / receiving antenna according to the second embodiment. Except for the above, the configuration is the same as that of the first embodiment.

In the key configured as described above, since the magnetic component of the radio wave transmitted from the transmitting / receiving antenna of the identification means is parallel to the surface of the grip 63, the radio wave slightly influences the metal grip 63. And the antenna coil 67 can efficiently receive this radio wave. The radio wave transmitted from the transponder 66 also
, The influence of the grip 63 is small. Note that the presence of the metal holding portion 63 causes the antenna coil 6
7, the resonance frequency of the antenna coil 6 is slightly changed.
When the number of turns of the coil portion 67b is increased so that the resonance frequency of the transponder 66 becomes a predetermined value in a state in which the transponder 7 is attached to the grip portion 63, the operating maximum distance of the transponder 66 can be extended.

FIGS. 8 and 9 show a fourth embodiment of the present invention. 8 and 9, the same reference numerals as those in FIGS. 6 and 7 indicate the same parts. In this embodiment, the plate-like grip 8
A concave portion 83a is formed on the three surfaces, and the transponder 66 is accommodated in the concave portion 83a. Except for the above, the configuration is the same as that of the second embodiment. In the key configured as described above, the transponder 66 is housed in the recess 83a, so that the thickness of the entire key 81 can be reduced. However,
The maximum operation distance of the transponder 66 is slightly shorter than that of the third embodiment.

[0024]

Next, examples of the present invention will be described in detail together with comparative examples. <Example 1> As shown in FIGS. 10 and 11, a key 91 consisting of only a plate-like gripping portion 93 was prepared by using a brass disc without a key body. In the center of this key 91 is a through hole 93a
Are formed, and a notch 93b having a width of 1 mm is formed around the through hole 93a.
Was formed. The outer diameter and thickness of this key 91 are 50
mm and 2 mm, and the diameter of the through-hole 93a was 36 mm. The transponder 96 was accommodated in the through hole 93a. This transponder 96 has an antenna coil 97
And an IC chip 98 which is electrically connected to the coil 97 and stores information unique to the key 91. The antenna coil 97 does not have a magnetic core member, and the wire diameter and the number of turns of the coated conductor forming the coil 97 are 0.07 mm and 3 mm, respectively.
70 times. The inner diameter, outer diameter, and thickness of the antenna coil 97 were 25 mm, 30 mm, and 1 mm, respectively. The key 91 having the transponder 96 was used as the first embodiment. <Embodiment 2> The number of turns of the covered conductor used for the coil portion is 3
The configuration was the same as that of Example 1 except that the number of times was changed to 75. A key having this transponder was designated as Example 2.

<Example 3> A key composed of only a plate-shaped grip portion without a key body was manufactured as a key using a disc made of brass. A through hole is formed at the center of the key, and a width 1
mm notch was formed. The outer diameter and thickness of this key are 50 mm and 2 mm, respectively, and the diameter of the through hole is 36 mm
Met. A transponder was housed in the through hole. The transponder has an antenna coil and an IC chip electrically connected to the coil and storing key-specific information. The antenna coil includes a magnetic core member formed of an Fe-based amorphous magnetic material and a coil wound around the magnetic core member. The diameter and thickness of the magnetic core member were 24.5 mm and 1 mm, respectively. The wire diameter and the number of turns of the coated conductor used for the coil portion are each 0.07 mm.
And 300 times, and the inner diameter, outer diameter and thickness of the coil portion were 25 mm, 29 mm and 1 mm, respectively. A key having this transponder was used as a third embodiment. <Embodiment 4> The number of turns of the covered conductor used for the coil portion is 3
The configuration was the same as that of Example 3 except that the number of times was changed to 04. The key having this transponder was designated as Example 4.

Example 5 A key composed of only a plate-shaped grip portion without a key body was manufactured from a rectangular plate made of brass. The length, width and thickness of this key are each 70mm,
30 mm and 2 mm. The transponder was placed on one surface of the key. The transponder has an antenna coil and an IC chip electrically connected to the coil and storing key-specific information. Antenna coil is META
It comprises a magnetic core member formed of GLAS2605S-2 (manufactured by Allied Chemical Company, iron-based soft magnetic amorphous material), and a coil portion wound around the magnetic core member. The magnetic core member has a length, width and thickness of 50 mm, 10 mm and 0.1 mm, respectively.
38 pieces of magnetic core foil of 025 mm were laminated and produced. The wire diameter and the number of turns of the covered wire used for the coil portion are 0.2 mm and 640 turns, respectively, and the covered wire is magnetized so that the axis of the antenna coil (the magnetization axis of the coil portion) is in the longitudinal direction of the magnetic core member. It was wound around a core member. A key having this transponder was designated as Example 5.

<Example 6> A key composed of only a plate-shaped grip portion without a key body was prepared as a key using a rectangular plate made of brass. The length, width and thickness of this key are each 70mm,
The recesses were 30 mm and 2 mm in length, width, and depth were 60 mm, 15 mm, and 1 mm, respectively, in the center of the surface of the key. An antenna coil was housed in the recess. The antenna coil includes a magnetic core member formed of METAGLAS2605S-2 (manufactured by Allied Chemical Co., Ltd., iron-based soft magnetic amorphous material), and a coil portion wound around the magnetic core member. The magnetic core member has a length, width and thickness of 5
38 magnetic core foils of 0 mm, 10 mm, and 0.025 mm were laminated and produced. The wire diameter and the number of turns of the covered wire used for the coil portion are 0.2 mm and 670 turns, respectively, and the covered wire is magnetized so that the axis of the antenna coil (the magnetization axis of the coil portion) is in the longitudinal direction of the magnetic core member. It was wound around a core member. Further, an IC chip was electrically connected to the antenna coil. A transponder was constituted by the antenna coil and the IC chip, and a key having this transponder was used as a sixth embodiment.

<Comparative Example 1> As shown in FIGS. 12 and 13, a key 1 consisting of a plate-shaped gripping portion 3 without a key body was made of a disc made of brass. A through hole 3a is formed at the center of the key 1. However, no cutout was formed in the periphery of the through hole of the key 1. The outer diameter and thickness of this key 1 are 5
0 mm and 2 mm, and the diameter of the through-hole 3a was 36 mm. The transponder 6 was accommodated in the through hole 3a. The transponder 6 has an antenna coil 7 and an I coil in which information unique to the key 1 which is electrically connected to the coil 7 is stored.
C chip 8. The antenna coil 7 did not have a magnetic core member, and the wire diameter and the number of turns of the covered conductor constituting the antenna coil 7 were 0.07 mm and 370 turns, respectively.
The inner diameter, outer diameter, and thickness of the antenna coil 7 were 25 mm, 30 mm, and 1 mm, respectively. The key 1 having the transponder 6 was used as Comparative Example 1. <Comparative Example 2> The number of turns of the covered conductor used for the coil portion was 4
Except having changed to 08 times, it comprised the same as the comparative example 2. The key having this transponder was designated as Comparative Example 3. <Comparative Example 3> The same transponder as in Comparative Example 1 (the number of turns of the covered conductor: 370) was used as Comparative Example 3. However, no key was used.

<Comparative Example 4> A key was formed in the same manner as in Example 3 except that no notch was formed in the periphery of the through hole. The same transponder as in Example 3 (the number of turns of the covered conductor: 300) was accommodated in the through hole of the key. The key having this transponder was designated as Comparative Example 4. <Comparative Example 5> The number of turns of the covered conductor used for the coil portion was 3
Except having changed to 31 times, it comprised the same as the comparative example 4. The key having this transponder was Comparative Example 6. Comparative Example 6 The same transponder as Comparative Example 4 (the number of turns of the covered conductor: 300) was used as Comparative Example 6. However, no key was used. <Comparative Example 7> The number of turns of the covered conductor used for the coil portion was 5
The transponder was constructed the same as in Example 5, except that it was changed to 75 times. Comparative Example 7
And However, no key was used.

<Comparative Test and Evaluation> The self-inductance (L) and the Q value of each antenna coil are determined by removing the IC chip from the transponder or the transponder alone attached to the key of each of Examples 1 to 6 and Comparative Examples 1 to 7. It was measured by an impedance analyzer (Hewlett Packard). In addition, the distance between the transponder or the transponder alone (connecting the removed IC chip to the antenna coil) attached to the key of each of Examples 1 to 6 and Comparative Examples 1 to 7 and the transmission / reception antenna of the identification means are changed. The maximum distance over which the information stored in the chip could be read was measured. Tables 1 to 3 show the measured values of the self-inductance (L (mH)), the Q value, and the maximum operating distance S (cm). Table 1
The frequency of the transmitted radio wave in Table 3 is the frequency (kHz) of the radio wave transmitted from the transmitting / receiving antenna of the identification means toward the antenna coil.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

As apparent from Table 1, in Comparative Example 1, L
And the Q value was low, the information of the IC chip could not be read, and the maximum operating distance could not be measured. In Comparative Example 2, the L value was high but the Q value was low, and the maximum operating distance was extremely short. This is probably because an eddy current was generated in the key in a direction to cancel the radio wave, in other words, the key reflected the radio wave. On the other hand, in Example 1, the L and Q values were slightly lower, but the maximum operating distance was much longer than in Comparative Example 2. In Example 2, the maximum operating distance was significantly longer than that in Example 1, and was increased to near the maximum operating distance in Comparative Example 3 (without a key).

As is clear from Table 2, in Comparative Example 4, L
And the Q value was low, the information of the IC chip could not be read, and the maximum operating distance could not be measured. In Comparative Example 5, the L value was high but the Q value was low, and the maximum operating distance was extremely short. This is probably because an eddy current was generated in the key in a direction to cancel the radio wave, in other words, the key reflected the radio wave. On the other hand, in Example 3, L was slightly lower, but the maximum operating distance was much longer than in Comparative Example 5. In Example 4, the maximum operating distance was significantly longer than that in Example 3, and was increased to near the maximum operating distance of Comparative Example 6 (without a key).

As is clear from Table 3, in Example 5, L
Although the Q value and the Q value slightly changed depending on the frequency of the transmitted radio wave, the maximum operating distance was longer than that in Comparative Example 7 (without a key). This is probably because the magnetic field component of the radio wave became parallel to the surface of the key. In the sixth embodiment, although the maximum operating distance is shorter than that of the fifth embodiment, the transponder is accommodated in the recess of the key, so that the entire thickness of the key and the antenna coil can be made smaller than that of the fifth embodiment.

[0037]

As described above, according to the present invention, a through hole is formed in a metal plate-like holding portion, a notch is formed in the periphery of the through hole, and an antenna coil and an IC chip are formed in the through hole. Since the transponder is accommodated, and the axis of the antenna coil is configured to be perpendicular to the surface of the gripper,
The entire key including the grip is integrally formed by a metal plate,
A predetermined strength that can withstand use as a key can be secured. Further, when the antenna coil receives a radio wave, the cutout formed in the plate-shaped grip does not generate an eddy current (generated in a direction to cancel the radio wave) around the through hole in the grip. The antenna coil can receive the radio wave efficiently. As a result, the maximum operating distance of the transponder can be extended without making the gripping portion unnecessarily large. A transponder having an antenna coil and an IC chip is mounted on the surface of the metal plate-shaped grip portion, and the antenna coil is composed of a magnetic core member and a coil portion wound around the magnetic core member. If the antenna coil is configured to be parallel to the antenna coil, the antenna coil receives a radio wave parallel to the grip portion, so that the radio wave is only slightly affected by the metal grip portion, and the antenna coil transmits the radio wave. Reception can be performed efficiently, and the maximum operating distance of the transponder can be extended. In addition, since the radio wave transmitted from the transponder is also parallel to the gripper, the influence of the gripper is small.

A concave portion is formed in the surface of the metal plate-shaped grip portion, and a transponder having an antenna coil and an IC chip is accommodated in the concave portion. The antenna coil is wound around the magnetic core member and the magnetic core member. If the transponder is configured so that the axis of the antenna coil is parallel to the surface of the grip portion, the transponder is housed in the concave portion of the grip portion, so that the thickness of the entire key can be reduced. Furthermore, if a lock capable of inserting the key or an identification means capable of reading information of an IC chip is provided near the lock, and the identification means is configured to read information stored in the IC chip via a transmission / reception antenna, When the key is inserted into the lock, the radio wave transmitted from the transmitting / receiving antenna is received by the antenna coil. When this radio wave is received by the antenna coil, the IC chip is activated by a mutual induction action between the transmission / reception antenna and the antenna coil, and a radio wave carrying key-specific information stored in the IC chip is transmitted from the antenna coil. Received. As a result, the identification means reads the information stored in the IC chip, determines whether this information is the information of the legitimate key, and operates the key inserted into the lock if the information is the legitimate information. It starts or unlocks, and if it is fake information, it does not start or unlock even if the key inserted into the lock is operated.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line AA of FIG. 2 showing a key according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG. 1;

FIG. 3 is a block diagram of the key and an identification device.

FIG. 4 is a side view of a main part of a driver's seat of an automobile including the key and the identification device.

FIG. 5 is a vertical sectional view of a main part of a door including a key and an identification device according to a second embodiment of the present invention.

FIG. 6 is a view of a key according to a third embodiment of the present invention, as viewed in the direction of arrow C in FIG. 7;

FIG. 7 is a sectional view taken along line DD of FIG. 6;

FIG. 8 is a view as seen from an arrow E in FIG. 9 showing a key according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view taken along line FF of FIG. 8;

FIG. 10 is a diagram showing a key and an antenna coil according to the first embodiment;
GG sectional drawing of FIG.

FIG. 11 is a sectional view taken along line HH of FIG. 10;

FIG. 13 shows a key and an antenna coil of Comparative Example 1.
Sectional view taken along the line II of FIG.

FIG. 13 is a sectional view taken along line JJ of FIG. 12;

[Explanation of symbols]

 11, 61, 81, 91 Key 13, 63, 83, 93 Plate-shaped grip 13a, 93a Through-hole 13b, 93b Notch 14, 44 Key cylinder (lock) 16, 66, 96 Transponder 17, 67, 97 Antenna coil 18, 98 IC chip 23, 43 Identification means 27, 47 Transmitting / receiving antenna 67a Magnetic core member 67b Coil portion 83a Recess

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuichi Kanda 3-3-8 Higashikanda, Chiyoda-ku, Tokyo Inside the Applied Electronics Research Laboratory, Inc. (72) Inventor Seiro Yawata 1-6-1, Otemachi, Chiyoda-ku, Tokyo No. 1 Intellectual Property Service Co., Ltd. F term (reference) 2E250 AA04 AA21 BB08 BB15 BB66 CC20 DD06 EE11 FF27 FF36 HH01 JJ03 JJ05 KK03 LL00 PP15 TT01

Claims (4)

[Claims] A through-hole (13a, 93a) formed in a metal plate-like gripping portion (13, 93), and a notch (13b, 93b) formed in a peripheral edge of the through-hole (13a, 93a). ) And a transponder (16, 96) housed in the through hole (13a, 93a), wherein the transponder (16, 96) is an antenna coil (17, 97).
And the key electrically connected to this antenna coil (17,97)
(11, 91) an IC chip (18, 98) for storing unique information, and the axis of the antenna coil (17, 97) is aligned with the grip portion (13, 93).
A key characterized by being configured to be perpendicular to the surface. 2. A key having a transponder (66) attached to a surface of a metal plate-like holding portion (63), wherein the transponder (66) is connected to an antenna coil (67) and the antenna coil (67). An IC chip (18) that is electrically connected and stores information unique to the key (61), wherein the antenna coil (67) is wound around the magnetic core member (67a) and the magnetic core member (67a). A key comprising: a coil portion (67b) provided so that an axis of the antenna coil (67) is parallel to a surface of the grip portion (63). 3. A key comprising: a concave portion (83a) formed on a surface of a metal plate-shaped grip portion (83); and a transponder (66) housed in the concave portion (83a). (66) has an antenna coil (67) and an IC chip (18) that is electrically connected to the antenna coil (67) and stores information unique to the key (81). It is composed of a magnetic core member (67a) and a coil part (67b) wound around the magnetic core member (67a), and the axis of the antenna coil (67) is parallel to the surface of the grip part (83). The key characterized by being comprised as follows. 4. The key according to claim 1, wherein the key (11,
61, 81, 91), and transmits a radio wave to the lock (14, 44) or the transponder (16, 66, 96) provided near the lock (14, 44) or the lock (14, 44). IC chip (18,9
8) identification means (23, 43) capable of reading information stored in the antenna coil (17, 67, 97).
Transmitting and receiving antennas (27, 47) interacting with the, the identification means (23, 43) the information stored in the IC chip (18, 98) via the transmitting and receiving antennas (27, 47) A key identification device configured to be read.