JPS60212575A - Passive keyless entry system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a keyless entry system and coded markers used therein. More particularly, the present invention relates to a keyless entry system that allows a person carrying a coded marker to easily and reliably enter a restricted area quickly.

The keyless entry system improved in accordance with the present invention is commonly employed as a convenience and as an additional anti-theft feature. There are currently three main types of keyless entry systems, including infrared systems,
Includes high frequency system, and electronic combination pad.

The infrared system consists of a hand-held source module and an infrared detection and decoding module placed at an appropriate location near the entrance to the restricted area. When the hand-held source module is activated and precisely aimed at the sensor decoder, the frequency-pulsed code 9 from the source is decoded and compared to the pre-programmed code.

If both coats 8 match, the locking mechanism is electronically released and the restricted area can be entered.

This system has several drawbacks. The most problematic of these is the one posed by the difficulties a user encounters when attempting to physically trigger the source module when the user's hands are occupied or restricted. be. Once activated, the source module must be accurately aimed and there must be no obstructions between the source module and the detection module. In case of bad weather and/or in low light conditions it is easily recognized that it is difficult to aim the source module and avoid obstacles between it and the detection module.

Such obstacles often come in the form of snow, dirt, ice, etc. Furthermore, under bright lighting, the detection module may not be able to detect the source module. Yet another disadvantage is posed by the fact that the source module and detection module each have separate power supplies, which makes the system less reliable.

A radio frequency (RF) system is placed with a hand-held source module at an appropriate location near sunrise in a restricted area.
F consists of a receiver-decoder.

RF systems are similar to infrared systems in that the source module must be activated by the body. However, there is no need to aim the RF source. When the source module is activated, the receiver communicates the coded RF multiplier signal to the decoder. coded RF
Once the double signal is confirmed, the locking mechanism is released and you can enter the restricted area. RF systems are unique in that the source module must be activated by the body (which is difficult if the user is wearing gloves) and requires its own power source. Like any system, it has its drawbacks. Additionally, other drawbacks of RF systems include:
RF generated by motors, wireless communication devices or thunderstorms
They are susceptible to interference, which can cause the receiver to fail or generate false signals that inadvertently release the locking mechanism.

A third type of keyless entry system is an electronic combination pad. The electronic combination pad 9 consists of a panel with approximately five buttons (keys) placed near the entrance to the restricted area. These buttons are usually marked with specific symbols. Alternatively, a sequence of geometric patterns can be used for the same purpose. If one wishes to enter the restricted area, the lock is released by pressing these buttons in a predetermined sequence. One of the disadvantages of electronic combination buttons is that the button must be physically activated or pressed. This operation must be performed when (1) the user is wearing gloves, (2) the key is obstructed by snow, dirt, or ice, and (3) the user is wearing gloves.
) Difficulty when the keypad must be operated in the dark or in bad weather. When using electronic combination pads, it is possible to forget the order or combinations. From the foregoing, these keyless entry systems can be optionally adopted for certain applications, but to date they have not been widely accepted by businesses and consumers.

According to the invention, keyless entry unlocks the locking mechanism of an entrance (e.g. a car door) to a restricted area by using a coded marker without the need for electrical power or physical contact with the entrance. system is provided. This marker is convenient to carry in a handbag or purse and is sized to be attached to a key chain.

Surprisingly, this marker is suitable for these items (handbags/
They still function even when placed inside a paper bag (paper pouch), requiring only momentary proximity of these items to a sensor placed near the entrance to the restricted area.

Generally, the keyless entry system of the present invention has an interrogation band rin.
terrogation zone).

The system includes oscillating means (including an interrogation coil) for generating a magnetic field having a frequency band within the interrogation band, and responsive within the interrogation band to impart signal identifiability to a marker within said frequency band. give.

It has a marker whose effective magnetic permeability changes substantially at a preselected frequency. The marker consists of at least one strip of magnetostrictive ferromagnetic material. The IJ tube is biased at a preselected frequency within the frequency band of the magnetic field, thereby activating it and tuning it into mechanical resonance. The system includes a detection means for detecting the resonance of the marker within the interrogation band, and a decoding means for comparing the detected marker resonance with a predetermined code to confirm a match between them. have. Actuation means connected to the decoding means are capable of causing the entry system to respond to a match indication from the decoding means.

In addition to unlocking the locking mechanism, the present invention's key entry system also electronically interfaces with a burglar alarm housed within a restricted area, thereby providing additional security against theft. can. Furthermore, the keyless entry system 1 connected to the interior of the automobile activates electronically operated automobile accessories, such as ignition interlock, steering wheel tilt, mirror position, seat adjustment, radio, stop, etc. It can be advantageously used to set the position.

The invention will be more fully understood, and other advantages will become apparent, by reference to the following detailed description of the preferred embodiments of the invention and the accompanying drawings.

FIG. 1 shows a typical automobile door with integrated side rearview mirrors and a center roof post.

FIG. 2 is an enlarged perspective view of the side rearview mirror of FIG. 1 incorporating the antenna of the present invention.

FIG. 3 is an enlarged side view of the roof post of FIG. 1 incorporating an antenna of another form of the present invention.

FIG. 4 is a block diagram of the keypad entry system of the present invention.

FIG. 5 is a projection diagram showing the components of a marker for use in the system of FIG.

FIG. 6 is a graph illustrating the voltage induced by a keyless entry system marker magnetochemically exchanging energy over a preselected frequency range.

FIG. 7 is a schematic diagram of the system of FIG. 4 installed at the entrance to a restricted area.

FIG. 8 is a schematic diagram of another form of the system of FIG. 4,
In this case, the system is adapted to install an ignition interlock in a motor vehicle in which the antenna of the invention is placed near the ignition switch.

The keyless entry system 50 can be made in a variety of sizes and configurations. It will therefore be appreciated that the present invention works with a wide variety of keyless entry systems. For purposes of illustration, the present invention will be described in connection with an entry system in which the restricted area is the interior of a motor vehicle and the locking mechanism of the motor vehicle is unlocked by a person in possession of a coded marker that allows quick and convenient entry into the vehicle interior. explain.

The present invention may be used in a variety of similar applications, such as keyless remote entry into restricted areas such as residences, office buildings, site locations, elevator floors, file drawers, computer terminals, etc. It will be readily recognized that it can be employed for keyless remote actuation of electronic devices with defined conditions. The invention therefore also encompasses variations of the preferred form in which keypad or remote entry is effected by a coded marker.

123 and 4, a keyless entry system 150 is shown. System 150 marker 1
00 has means for generating a predetermined code. The keyless entry system 150 has means for remotely interrogating the marker 100 and reproducing a predetermined code contained in the marker. The detection means 120 has means for determining whether this reproduced code is the correct code necessary to unlock the locking mechanism 130 of the vehicle. When the holder of the coded marker 100 enters the interrogation band provided by the antenna ]]0, the keyless entry system [50] is activated via the proximity sensor 115. Sensor 115 may be any conventional proximity sensor that is tuned to change its electronic state in response to the presence of an object in its vicinity. Objects of this type include a user's hand, keys or markers. There are various types of proximity sensors on the market, including magnetic, capacitive,
Includes what is known as inductive, acoustic, etc. Capacitive proximity sensors detect a wide variety of objects and require only a small amount of electricity or force. Therefore, this type of sensor is preferred. Proximity sensor 115 is system 15
It requires only a small amount of energy compared to zero. This activates the system 150 only if the object is within the interrogation zone. This situation is the proximity sensor 11
5 within the interrogation band]5. This thus eliminates the energy loss that would otherwise occur due to system 150 having to continuously scan the interrogation band . When activated by the proximity sensor 115, the oscillating means 170 interrogates the marker 100 and causes it to play the code embedded in the marker. Detection means 120 detects this code and transmits it to decoding means 140, which compares this code with predetermined codes to confirm a match between them. The activation means 145 can cause the keyless entry system 50 to respond to a matching instruction from the decoding means 140 by releasing the locking mechanism 30.

Marker 00 is designed so that it can represent multiple codes. Marker 100, as shown in FIG. Consisting of

Container 16 consists of two parts, a boat 62 and a cover 44. This container must be constructed so that the strip 18 remains undamped or freely vibrating when placed in the boat 62 and enclosed by the cover 44, which is true for all internal dimensions of the container 16. ] This can be achieved by leaving a clearance of mπ. Coded markers having the structure of marker 100 are visually indistinguishable from each other. The structure of this marker allows it to be easily attached to a key chain or inserted into a purse or purse. More importantly, the marker '00 is still operable when stored in a handbag or paper bag.

Marker ] 00 essentially has the formula MaN 1. O, XdY
, Z 1 (where M is at least one of iron and cobalt), N is nickel, ○ is at least one of chromium and molybdenum, and X is at least one of boron and phosphorus. A, Y is silicon, 2 is carbon, 6α"~°"f' is an atom, "la" is about 35-85, h°" is about 0-45,"
C" is about 35-85, II d l+ is about 5-22,
IIe" is about O~15, and f" is about O~2,
the magnetostrictive amorphous alloy in the form of a strip 18 having a first component of a composition varying from 15 to 25).

Antenna system 110 is responsible for defining interrogation band 15 . Preferably the antenna is placed on a motor vehicle. 1st
The figure shows two possible locations for the antenna system 110 in a motor vehicle. The convenient location of the side rearview mirror 10, which is integrated with the driver's door, makes it ideally suited for the antenna system 110. FIG. 2 shows an enlarged view of the side rearview mirror with the antenna system 110 installed. The antenna system 110 consists of two interrogation coils 60 and a receive coil 50 mounted coplanar with each other. The integral side rearview mirror 10 consists of two main parts: a rotating shell 40 and a mirror 45. Coplanar antenna system 10 can be easily installed in the space provided by rotatable shell 40, directly behind mirror 45. This arrangement completely hides the antenna system 110 and at the same time provides a well-defined interrogation band 15.

In operation, the oscillating means 170 activates the interrogation coil 60 to produce a magnetic field having a predetermined frequency vector. This magnetic field is distributed throughout the interrogation zone] 5 and can therefore activate any marker 100 that enters the interrogation zone 15. Marker] 00 is the interrogation band]
5, the receiving coil 50 activates the marker 10.
0 and transmits the coded signal to detection means 120. The decoding means 140 then verifies the code by comparing the detected code with a predetermined internal code. Once a match is confirmed, actuating means 145 activates entry system 150.
The locking mechanism 130 can be released. The keyless entry system 150 is powered by the vehicle's battery. However, this system has a proximity sensor 115
Fires only when triggered. The keyless entry system 150 can be located at any convenient external location within the vehicle.

System 150 does not require major modifications to the vehicle, thus making keyless entry system 150 an easily installed item.

In a preferred embodiment of the invention, interrogation coil 60
are antenna coils 6], 62 arranged close to each other.
Consisting of The antenna coils Fil, 62 are driven alternately by the oscillating means 170 at phase angles of 08 and 180° relative to each other. This arrangement of the antenna coils 6], 62 allows the marker]00 to be detected regardless of its orientation within the interrogation band J5.

The oscillating means 170 in the preferred embodiment is tuned to abruptly impart a sinusoidal frequency to the interrogation coil 2 which includes each of the preselected marker frequencies. Other possible oscillation means that can be used instead to give the marker its preselected frequency]70
There are some outputs. This kind of alternative oscillation means 17
00 examples include: (1) a sweeping means adjusted to sweep each of the preselected different frequencies of the marker; (2) a width 1 in the interrogation coil 210;
oscillation means adjusted to give a pulse of //2(fr) (where fr is a preselected frequency); (3) oscillation adjusted to give a sudden noise to the interrogation coil 210; (4) oscillation means adjusted to abruptly impart a sweeping sinusoidal frequency to interrogation coil 210;

In operation, the oscillating means 20 provides an abrupt sinusoidal frequency to the interrogation coil 210. After the abrupt form of the interrogation signal has ceased, the marker will continue to vibrate, thereby producing damped oscillations at its resonant frequency. This vibrating marker is connected to the receiver coil 2 at each resonant frequency.
20 will induce a voltage. The detection means 120 is synchronized by the synchronization means 200 with the oscillation means 170 in such a way that it can only be detected after the abrupt interrogation of the resonant frequency from the receiver coil 220 has ceased. Detection means] 20 measures the value of the resonant frequency of the marker 100 and provides a frequency code. The decoding means 140 compares the frequency code of the cigarette with a predetermined code and causes the actuating means 145 to release the locking mechanism 130 if a match is found between them.

Antenna system 11 providing various convenient interrogation bands
There are several other configurations of 0. One such alternative arrangement is shown in FIG. 1 as a center roof post 20. Many cars have a non-metallic decorative panel on the center roof post 20, where the antenna system
It can be easily installed as shown in the figure. The decorative panel 90 has two interrogation coils 80 embedded in the hidden side.
and one receive coil 70, which provides a convenient hidden interrogation band. Several other antenna system 110 locations include embedding the system directly into a window pane or meter at a suitable location. This type of antenna system 110 is connected to a non-metallic body part (fc
For example, it can be installed on a metal body part in a suitable position below the door panel 30).

The use of keyless entry system 150 need not be limited to locking mechanisms. By installing a personal marker and correlating this personal marker code with a personal specification, any electronically actuated device can be adapted to the personal specification. This does not restrict entry into the vehicle. This is because only part of the code is required to activate the locking mechanism, and the remaining code can be designated for individuals. Examples of electronic actuators include seat adjustments, radio adjustments, mirror position, steering wheel tilt, stop (5uspθn5ion) adjustments, etc.

Another use of the keyless entry system 150 is shown in FIG. In this case, system 150 is configured to provide an ignition interlock to the vehicle.

The ignition interlock is installed near the ignition switch of the car.
The system 150 consists of an antenna coil 400. FIG. 8 shows the ignition of a motor vehicle in which the ignition switch 410 is located on the steering column 420. Markers 430 of system 150 are attached to keychain 440 .

A key 450 for the ignition switch 410 is also attached to the key chain. Therefore, the key 450 is turned into the ignition switch 410.
When inserted into the antenna coil 4000, the marker 430 is automatically placed near the antenna coil 4000. The preferred form of ignition interlock requires that both ignition key 450 and marker 430 be present in order for the ignition device to be actuated. The ignition interlock essentially locks the ignition off if the above conditions are not met.

The means for locking the ignition includes an electronically actuated mechanical lock or a well-concealed electronic switch. Ignition interlocks provide an additional style of safety and security to your vehicle.

Another form of keyless entry system is shown in FIG. In this case, the system is shown in conjunction with a restricted area within a building. One version uses a coplanar antenna coil 3'OOQ mounted on the wall of the hallway near the entrance 310 to the restricted area 350. When a person possessing marker 1.00 with the correct code brings the marker 100 close to the coplanar antenna coil 300, the locking mechanism 360 at the entrance 3 ], O is released and the restricted area 350 can be entered. . In the second form, the restricted area 350
Detection coil 3 located on opposite sides of inlet 340 to
20 and an oscillation coil 330 are used. According to this embodiment, when a person carrying marker 100 with the correct code passes through interrogation zone 380 defined by detection coil 320 and oscillation coil 330, restricted area 350
can enter. The advantage of this form is that the marker 10
0 means that it does not need to be in a special position. In particular, marker 00 functions at all locations within the interrogation zone formed by the area between detection coil 320 and oscillation coil 3300.

The keyless entry system 150 can be arranged to provide a number of interrogation bands, each consisting of an individual antenna system 110 and a proximity sensor. This configuration increases the capacity of system 150 by operating one set of antenna systems 110 on one electronic network of system 150. An example of this is a car in which three antenna systems 110 and proximity sensors 115 are installed, which are connected to one electronic network. - A set of antenna systems 110 and proximity sensors 115 are placed on the driver's door and adjusted to allow entry into the vehicle interior. Second
The set is placed near the trunk of the car and is adjusted so that it can reach inside the trunk.

For example, an interrogation band 15 formed by a second set of antenna systems 110 and a proximity sensor 115 may be placed in the trunk of an automobile and release its locking mechanism in response to the presence of a marker therein. I can do it.

This form of the invention not only allows access to the trunk of a car, but also prevents the trunk from being locked with the car key inside. A third set is placed near the vehicle's ignition switch and is adjusted to function as an ignition interlock.

Each set of these antenna systems】10 and proximity sensor?
-115 is separately triggered in response to the presence of an object in one of the interrogation bands.

It has been found that markers comprising strips of magnetostrictive amorphous material are particularly suitable for mechanical resonance at preselected frequencies of the incident magnetic field. Without intending to be bound by any theory, it is believed that direct magnetic coupling between the alternating magnetic field and the marker 100 occurs through the following mechanism in the marker having the above composition.

When a ferromagnetic material (eg, an amorphous metal ribbon) is placed within a magnetic field, the magnetic domains of the ribbon grow and/or rotate. This movement of magnetic domains stores magnetic energy, with a small amount of energy being lost as heat. When the magnetic field is removed, the domains return to their original orientation and release their stored magnetic energy, again losing a small amount of energy as heat. Amorphous metals have high efficiency in this mode of energy storage. Since amorphous metals have no grain boundaries and high resistivity, their energy loss is extremely low.

Still other modes of energy storage are possible if the ferromagnetic ribbon exhibits magnetostriction. In the presence of a magnetic field, the magnetostrictive amorphous metal ribbon will have magnetically stored energy as described above, but will also have mechanically stored energy due to magnetostriction. This amount of stored mechanical energy can be expressed by the equation Ue=(1/2) where S is the stress and strain. This additional mode of energy storage is seen as an increase in the effective permeability of the ribbon.

When the magnetostrictive ribbon is subjected to alternating current and direct current magnetic fields (such as can be generated by alternating current and direct current in a solenoid), energy is stored and released alternately with the frequency of the alternating magnetic field. The storage and release of magnetostrictive energy is greatest at the material's mechanical resonance frequency and is minimal in its anti-resonance state. This storage and release of energy induces a voltage in the heater coil through the east density change of the ribbon.

This flux density change is also seen as an increase in effective magnetic permeability at the resonant frequency and a decrease in the anti-resonant state. This therefore actually increases or decreases the magnetic coupling between the drive solenoid and the second pull-up solenoid, respectively. The voltage induced purely by magnetic energy exchange has a linear relationship with frequency, and the change in voltage with frequency is small within a certain frequency range. The voltage induced by magneto-mechanical energy exchange also has a linear relationship with frequency, except near the mechanical resonance state. For thin ribbons, the mechanical resonant frequency is given by:

fr = (n,/2L)(VD)″/2 L% in the above formula
and D are the length, Young's modulus and mass density of the ribbon, and L indicates the radio frequency order. Therefore, when sweeping around the frequency fR of the alternating magnetic field, a characteristic signal is generated. As shown in FIG. 6, an anti-resonance peak occurs immediately after the resonance peak. The anti-resonance peak occurs when the stored energy approaches zero.

The transfer of magnetic and mechanical energy described above is called magneto-mechanical coupling (MMC') and is found in all magnetostrictive materials. The efficiency of this energy transfer is proportional to the square of the magneto-mechanical coupling coefficient (K), which is defined as the ratio of mechanical energy to magnetic energy. Phenomenologically, K is (where fr and fa are resonant frequency and anti-resonant frequency). The larger the coefficient K, the larger the potential difference between the resonance peak and the anti-resonance valley. K cut out
The larger the value, the greater the difference in frequency between resonance and anti-resonance.

Therefore, when K is large, the MMC phenomenon can be observed.

The coupling coefficient is influenced by the level of bias magnetic field present, the level of internal stress (or structural anisotropy) present, and the level and direction of magnetic anisotropy in a particular amorphous metal. Annealing amorphous metals relieves internal stresses and thus increases K. The structural anisotropy is small because the ribbon is amorphous, and this also increases K. A properly oriented magnetic field significantly increases the coupling coefficient. The motion of magnetic domains is large when the ribbon has magnetic anisotropy perpendicular to the interrogating magnetic field. Due to demagnetizing field effects, it is practical to interrogate the ribbon only along its length (which is its longest dimension). The induced magnetic anisotropy should therefore be across the length of the ribbon.

The maximum value of K is obtained by annealing the ribbon in a saturation magnetic field perpendicular to the length of the ribbon (cross-field annealing).

For a 14 inch ribbon, a magnetic field of several hundred oersteds is required. The optimum time and temperature for annealing depends on the alloy used. For example, iron-boron-silicon alloy is 4
Cross-field annealing at 00°C for 30 minutes gives the best coupling (K) 0.90). By this annealing, 1
Oersted's optimum bias magnetic field is obtained. For alloys with the composition detailed above, the annealing temperature is approximately 300
˜450° C., and the annealing time is about 7 to 120 minutes.

Annealing also affects the bias field required to optimize K. For certain amorphous metals with certain annealing, the coupling is highly dependent on the bias magnetic field. At zero and saturation fields, the coupling is zero (no resonance and anti-resonance phenomena). For a given alloy, there is an optimum bias field that gives the maximum K. For alloys having the compositions detailed herein, the bias field required to optimize K is approximately Oj~2° Oersteds.

Although most magnetostrictive materials will exhibit some degree of MMC, amorphous metals exhibit extremely high coupling coefficients;
Therefore, it is highly preferred. Cast raw amorphous metals provide higher K than most other magnetostrictive materials. Cross-field annealing does not require higher K than amorphous metals. Amorphous metals have (a) low magnetic loss (no grain boundaries, high resistivity), (b) low structural and stress anisotropy, (C) reasonable magnetostriction, and (d ) has a high value because it can impart useful magnetic anisotropy.

Amorphous alloys (α) have a high value even when cast,
(6) mechanically strong, tough, and ductile; (C) requires a low bias magnetic field; and (d) has extremely high magnetostriction (generates large forces upon resonance;
(harder to decrease), it forms a good marker. It will therefore be appreciated that the amorphous metal making up the marker of the present invention does not need to be annealed and can be employed in the marker "as cast".

Examples of amorphous ferromagnetic marker compositions encompassed by the present invention are shown in Table 1 below.

Table 1 Fe78S19B□30.35〉090Fe79Si,
B,, 0.31)090Fe8. B□3.5Si3
．． 5G20.22)0.90Fe67Co□8B,S
i, 0.45 0.72Fθ4oN138M0480
Examples of amorphous metals that have been found to be unsuitable for use as markers for 80230.50 object monitoring systems are shown in Table 2.

Table 2 Composition c%) Example 1 Example 2 Ni atomic coefficient 71.67 Ni atomic coefficient 1'i5.63
Weight ratio 84.40 Weight % 76.97 Gr At % 5-75 Or At % 11.55 Weight % 6 Weight % 12. O B atomic ratio 12゜68 B atomic ratio 11.58% by weight
2.75 wt% 2.5 Si atom 7-10 Si atom% 7.13 wt% 4 wt% 4 Fe atom% 2-23 Fe atom% 3.14 wt% 2.5 wt% 3.5 G atom H, 25 C atoms, 12% by weight. 0
6 weight%, 03 P atomic ratio, 033 P atomic ratio - weight%, 02
Weight% - 8 atoms, 031'S atoms - Weight%, 0
2% by weight - A7 atomic unit, 093 AA? Atomic ratio - weight%
, 05 wt% - T1 atomic ratio, 052 Ti atomic ratio - wt%
. 05 weight % - Zr atomic %, 027 Zr atomic ratio - weight %,
05 weight% - Co atomic%, 085 Co atomic ratio, 85 weight ratio
, 1% by weight 1.0 The amorphous ferromagnetic metal marker of the present invention is prepared by adding a small amount of a melt of the desired composition to an alloy well known in the art of amorphous true alloy technology at a rate of at least about 0°C/sec. Rapid cooling method (e.g. U.S. Patent No. 3)
．． No. 856,513 (see Cheno et al.) and cooling. The purity of all compositions is that commonly found in commerce.

Various methods are used to process continuous ribbons, wires, sheets, etc. Generally, a particular composition is selected, powders or granules of the required elements in the desired proportions are melted, homogenized, and the molten alloy is quenched on a quenching surface, such as a metal cylinder rotating at high speed.

Under these quenching conditions a metastable homogeneous ductile material is obtained. Metastable materials may be amorphous, in which case there is no extensive order. X-ray diffraction ξ turns of amorphous alloys show only diffuse halos similar to those observed for inorganic oxide glasses. This type of amorphous alloy is sufficiently ductile to allow subsequent handling (e.g. punching out complex shaped markers from alloy ribbons without destroying the marker's signal identity). must be amorphous at least 50 times. Preferably the amorphous metal marker should be at least 80% amorphous to achieve good ductility.

The metastable phase may be a solid solution of the constituent elements.

In the case of the markers of the present invention, metastable solid solution phases of this type are not necessarily produced by conventional processing methods used in the art of crystalline alloy processing. The X-ray diffraction pattern of the solid solution alloy exhibits the sharp diffraction pattern characteristic of crystalline alloys, with some broadening due to the desired fine-grained crystals. Metastable materials of this type are also ductile when produced under the conditions described above.

Although the present invention has been described in considerable detail above, it is not necessary to adhere to this detailed description, and it is obvious that various changes and modifications can be made to those skilled in the art. It is included within the scope of the present invention.

[Brief explanation of drawings]

FIG. 1 shows a typical automobile door with integrated side rearview mirrors and a center roof post. FIG. 2 is an enlarged perspective view of the side rearview mirror of FIG. 1 incorporating the antenna of the present invention. FIG. 3 is an enlarged side view of the roof post of FIG. 1 incorporating an antenna of another form of the present invention. FIG. 4 is a block diagram of the keypad entry system of the present invention. FIG. 5 is a projection diagram showing the components of a marker for use in the system of FIG. FIG. 6 is a graph illustrating the voltage induced by a keyless entry system marker magnetochemically exchanging energy over a preselected frequency range. FIG. 7 is a schematic diagram of the system of FIG. 4 installed at the entrance to a restricted area. FIG. 8 is a schematic diagram of another form of the system of FIG. 4,
In this case, the system is adapted to install an ignition ink-lock on a motor vehicle in which the antenna of the invention is placed near the ignition switch. In the drawings, each symbol represents the following. 10: Rearview mirror; 15: Interrogation band 20: Roof post; 30 Nidoor panel 40: Rotating shell; 45: Mirror 50: Receiving coil; 60: Interrogating coil 6], 62: Antenna coil 70: Receiving coil; 80: Interrogation coil 90: makeup nononel; 100: marker 110: antenna; 115: proximity sensor 120: detection means; 1
30: Locking mechanism 140: Decoding means; 145: Actuation means 150: Keyless entry system; 170: Oscillating means; 200: Synchronizing means 210: Interrogation coil; 220: Receiving coil J6: Marker container; 1
8 Nislip 44: Cover; 62: Boat 300: Antenna coil; 3] 0: Entrance 320: Detection coil; 330: Oscillation coil 340 350: Restricted area 360: Locking mechanism; 380: Interrogation band 400: Antenna coil ; 4] 0: Ignition switch 420: Steering column;
43('): Marker 440: Keychain; 45
0: Key patent applicant Allied Carporation No. 1
Continued page Priority claim April 9, 1984 [Sir] United States (US)
[Stock] [Phase] 198th May 7th [Phase] United States (LJ S)
[Co., Ltd.] ■Inventor Michael Satsuchome Ameril Ido. 0 Inventor Jeffrey C.W. Ameril Vansky Tudora 97961 07887 New Chassis, CA 07092. 282 Mountain Sasumito Road, New Chassis, United States 07871. Sparta, Wound Road 63

Claims (1)

[Scope of Claims] (I) (a) Means for determining an interrogation band; ψ) Oscillation means for generating a magnetic field having a frequency band within the interrogation band, wherein the oscillation means (C) in response to at least one of the interrogation bands;
a marker whose effective magnetic permeability varies substantially at a predetermined frequency within the frequency band that imparts signal distinctiveness to the marker, the marker comprising at least one strip of magnetostrictive ferromagnetic material; (d) said strip is magnetically biased at said preselected frequency within said frequency band of a magnetic field and thereby activated and tuned to mechanical resonance; (e) decoding means for comparing the detected marker resonance with a predetermined code to confirm correspondence therebetween; and ( f) A keyless entry system comprising activation means capable of causing the entry system to respond to a match indication from said decoding means. (2) further comprising activation means for detecting the presence of an object within the interrogation band and activating the oscillation means in response to the presence of the object; Keyless entry system. (3) a proximity sensor with activation means disposed near the interrogation band and adjusted to change its electronic state in response to the presence of an object approaching the interrogation band; and oscillation means responsive to the change in electronic state; A keyless entry system according to claim 2, comprising a switch opening/closing means for starting the keyless entry system. (4) At least one oscillation means and one detection means each.
A keyless room entry system according to claim 1, comprising two antenna coils. (5) The keyless room entry system according to claim 4, wherein the antenna coils of the oscillating means and the detecting means are in the same plane. (6) The key according to claim 5, wherein the oscillation means comprises a pair of antenna coils arranged close to each other and alternately driven by the oscillation means at phase angles of 00 and 180 degrees with respect to each other. No entry system. (Force) The harsh entry system according to claim 4, wherein the system is installed in a motor vehicle, and the antenna coil of the oscillation means and the detection means is installed in a side rearview mirror of the motor vehicle. (8 ) (α) Defective means of determining multiple interrogation bands; (b
) oscillation means associated with each interrogation band for generating a magnetic field having a frequency band 8 within the interrogation band, the oscillation means comprising a plurality of interrogation coils; at least one of which is located in each of the interrogation bands; (C) at least one of the interrogation bands;
a marker whose effective magnetic permeability changes substantially at a predetermined frequency in response to a signal discriminability to the marker within said frequency band 8, said marker being made of a magnetostrictive ferromagnetic material; at least one strip of , said strip being magnetically biased at said preselected frequency within said frequency band of a magnetic field and thereby activated and tuned to mechanical resonance; (d) a plurality of detection means for detecting the resonance of the marker within the interrogation band; (e) comparing the resonance of the detected marker with a predetermined court 8 to confirm the coincidence therebetween; and σ) a plurality of actuation means capable of causing a plurality of electronic devices associated with the entry system to respond to a match indication from the decryption means. (9) further comprising a plurality of activation means for detecting the presence of an object within each interrogation band and activating the oscillation means in response to the presence of the object. The keyless entry system described in section. (10) a proximity sensor, the activation means being arranged in the vicinity of one different interrogation band and adjusted to change its electronic state in response to the presence of an object in its vicinity; 10. A keyless entry system as claimed in claim 9, comprising a switch opening/closing means for responsively starting the oscillating means.