JP2000054699A - Key-less entry system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key-less entry system of a bidirectional communication type capable of improving the responsiveness of locking/unlocking a vehicle door in the transmission cycle of a request signal when a transmitted signal is received, while maintaining power saving performance with the transmission cycle of the request signal when the transmitted signal is not received, by shortening the transmission cycle of the request signal when an onboard machine receives the transmitted signal. SOLUTION: A key-less entry system for doing away with switching operation includes an onboard machine 1 for transmitting a request signal B in a predetermined cycle and a portable machine 2 for transmitting a transmitted signal (d) when receiving the request signal B, the onboard machine 1 locking/unlocking a vehicle door depending on the receiving intensity of the transmitted signal (d). The onboard machine 1 shortens the transmission cycle of the request signal B when receiving the transmitted signal (d).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises an in-vehicle device for transmitting a request signal, and a portable device for transmitting a transmission signal (radio signal) when receiving the request signal, and the in-vehicle device receives the received signal strength of the transmission signal. The present invention relates to a keyless entry system that locks or unlocks a vehicle door according to a two-way communication type and has no switch operation.

[0002]

2. Description of the Related Art Conventionally, as a keyless entry system without a switch operation, there are, for example, the devices described in JP-A-6-58029 and JP-A-9-303021. That is, the former disclosed in Japanese Patent Application Laid-Open No. 6-58029 includes a portable device carried by an occupant or an operator, an in-vehicle device and a lock unit mounted on a vehicle, and the portable device opens a door of the vehicle. An unlock signal for unlocking is always transmitted at a predetermined cycle, and the vehicle-mounted device transmits an unlock signal when the unlock signal from the portable device is received at a predetermined electric field strength or higher at every predetermined period. Is a one-way communication type device configured to output a locking operation signal when the electric field strength is equal to or less than a predetermined electric field strength.

In the latter Japanese Patent Application Laid-Open No. 9-303021, an in-vehicle device driven by using a power supply of an in-vehicle battery is provided, and a portable device receives a request signal constantly transmitted from the in-vehicle device. When the mobile device creates and transmits a transmission signal, and the transmission signal is received by the on-board device,
The in-vehicle device is of a two-way communication type configured to unlock or lock the door keylessly via a door lock actuator in accordance with the strength of a predetermined electric field strength of the received transmission signal.

However, in any of these conventional devices, the number of transmissions of a transmission signal transmitted and output from a portable device or the transmission cycle of a request signal transmitted and output from a vehicle-mounted device are uniform, so that power saving and vehicle doors are not performed. There is a problem that it is difficult to achieve both lock and unlock responsiveness (responsiveness).

For example, if the request signal transmission cycle is set short for the purpose of improving the responsiveness of locking and unlocking the vehicle door, the number of request signal transmissions per unit time increases, and the responsiveness improves.
Because of this, power consumption becomes large, and it was not possible to achieve both of these (power saving and response).

[0006]

SUMMARY OF THE INVENTION According to the first aspect of the present invention, in a keyless entry system of a two-way communication type, when a vehicle-mounted device receives a transmission signal, the transmission cycle of the request signal is shortened. A keyless entry that can improve the lock / unlock responsiveness of the vehicle door with the transmission cycle of the request signal when the transmission signal is received, while maintaining the power saving by the transmission cycle of the request signal when the transmission signal is not received. The purpose is to provide the system.

According to a second aspect of the present invention, in the keyless entry system of the two-way communication type, when the reception strength of the transmission signal is high, the onboard unit shortens the transmission cycle of the request signal, thereby receiving the transmission signal. It is possible to improve the responsiveness of locking and unlocking the vehicle door by the transmission cycle of the request signal when the reception intensity of the transmission signal is high while maintaining the power saving by the transmission cycle of the request signal when the reception intensity is not large. It aims to provide a keyless entry system that can be used.

According to a third aspect of the present invention, in the keyless entry system of the two-way communication type, the number of transmissions of the transmission signal is increased when the reception strength of the request signal received by the portable device is larger than the first predetermined value. By that
The vehicle door is controlled by the number of transmissions of the transmission signal when the reception intensity of the request signal is greater than the first predetermined value while maintaining power saving by the number of transmissions of the transmission signal when the reception intensity of the request signal is less than the first predetermined value. It is an object of the present invention to provide a keyless entry system capable of improving the responsiveness of locking and unlocking.

According to a fourth aspect of the present invention, in the keyless entry system of the two-way communication type, when the vehicle-mounted device receives the transmission signal, the transmission cycle of the request signal is shortened and the reception strength of the transmission signal is high. The transmission period of the request signal when the transmission signal is received and the reception intensity is large while maintaining power saving by the transmission period of the request signal when the transmission signal is not received by further shortening the transmission period of the request signal. Accordingly, it is an object of the present invention to provide a keyless entry system capable of further improving the responsiveness of locking and unlocking a vehicle door.

According to a fifth aspect of the present invention, in addition to the object of the third aspect, a second predetermined value which is larger than the first predetermined value is set, and a request signal received by the portable device is received. By reducing the number of transmissions of the transmission signal when the intensity is larger than the second predetermined value, the number of transmissions is reduced when the occupant is close to the vehicle and the necessity of improving the responsiveness is low, thereby giving priority to power saving. Accordingly, it is an object of the present invention to provide a keyless entry system capable of further improving power saving.

According to a sixth aspect of the present invention, in addition to the object of the second aspect, the on-vehicle device extends the request signal transmission cycle when the reception intensity of the transmission signal is greater than the set value. Accordingly, when the occupant is close to the vehicle and the necessity of improving responsiveness is low, the transmission cycle is lengthened to prioritize power saving, thereby enabling further improvement of power saving. The purpose is to provide.

[0012]

According to a first aspect of the present invention, there is provided an on-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, The on-vehicle device is a keyless entry system without a switch operation for locking or unlocking a vehicle door according to the reception strength of the transmission signal. The on-vehicle device is a keyless device for shortening a transmission cycle of a request signal when a transmission signal is received. It is an entry system.

According to a second aspect of the present invention, there is provided an on-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device transmits the request signal. A keyless entry system without a switch operation for locking or unlocking a vehicle door according to a signal reception strength, wherein the on-vehicle device shortens a transmission cycle of a request signal when reception strength of a transmission signal is high. It is characterized by being.

According to a third aspect of the present invention, there is provided an on-vehicle device for transmitting a request signal at a predetermined cycle, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device transmits the request signal. A keyless entry system without a switch operation for locking or unlocking a vehicle door according to a signal reception intensity, wherein the portable device counts the number of transmissions of the transmission signal when the reception intensity of the request signal is greater than a first predetermined value. It is characterized by a keyless entry system that increases the size.

According to a fourth aspect of the present invention, there is provided an in-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the in-vehicle device transmits the request signal. A keyless entry system without a switch operation for locking or unlocking a vehicle door according to a signal reception intensity, wherein the in-vehicle device shortens a transmission cycle of a request signal when a transmission signal is received, and reduces a reception intensity of the transmission signal. Is large, the keyless entry system further shortens the transmission cycle of the request signal.

According to a fifth aspect of the present invention, in addition to the configuration of the third aspect of the invention, a second predetermined value larger than the first predetermined value is provided, and the portable device transmits a request signal. The keyless entry system is characterized in that the number of transmissions of a transmission signal is reduced when the reception strength is greater than a second predetermined value.

According to a sixth aspect of the present invention, in addition to the configuration of the second aspect, the on-vehicle device extends the request signal transmission cycle when the reception intensity of the transmission signal is greater than a set value. Keyless entry system.

[0018]

According to the first aspect of the present invention, the above-mentioned on-vehicle device transmits a request signal at a predetermined cycle, and the portable device which has received the request signal transmits a transmission signal, and the on-vehicle device transmits the request signal. The device locks or unlocks the vehicle door according to the strength of the transmission signal when the transmission signal is received, but the above-described vehicle-mounted device shortens the transmission cycle of the request signal when the transmission signal is received.

Therefore, while the power saving is maintained by the transmission cycle of the request signal when the transmission signal is not received, the vehicle door is locked and unlocked at the transmission cycle of the request signal when the transmission signal is received (short transmission cycle). There is an effect that the responsiveness can be improved.

According to the invention described in claim 2 of the present invention,
The above-mentioned in-vehicle device transmits a request signal at a predetermined cycle, the portable device having received the request signal transmits a transmission signal, and the in-vehicle device locks or unlocks the vehicle door according to the strength of the transmission signal when receiving the transmission signal. However, the above-mentioned in-vehicle device shortens the transmission cycle of the request signal when the reception intensity (reception electric field intensity) of the transmission signal is high.

As a result, while maintaining power saving by the transmission cycle of the request signal when the reception strength of the transmission signal is not large, the transmission cycle of the request signal when the reception strength of the transmission signal is high (short transmission cycle) is maintained. Lock the vehicle door,
There is an effect that the response of the unlock can be improved.

According to the third aspect of the present invention,
The above-mentioned in-vehicle device transmits a request signal at a predetermined cycle, the portable device having received the request signal transmits a transmission signal, and the in-vehicle device locks or unlocks the vehicle door according to the strength of the transmission signal when receiving the transmission signal. However, the portable device increases the number of transmissions of the transmission signal when the reception intensity of the request signal is greater than the first predetermined value.

Therefore, while maintaining power saving by the number of transmissions of the transmission signal when the reception intensity of the request signal is equal to or lower than the first predetermined value, the transmission signal when the reception intensity of the request signal is higher than the first predetermined value is maintained. There is an effect that the response of locking and unlocking the vehicle door can be improved by the number of times of transmission.

According to the invention described in claim 4 of the present invention,
The above-mentioned in-vehicle device transmits a request signal at a predetermined cycle, the portable device having received the request signal transmits a transmission signal, and the in-vehicle device locks or unlocks the vehicle door according to the strength of the transmission signal when receiving the transmission signal. However, the above-mentioned in-vehicle device shortens the transmission cycle of the request signal when receiving the transmission signal, and further shortens the transmission cycle of the request signal when the reception strength of the transmission signal is high.

As a result, the power saving is maintained by the transmission cycle of the request signal when the transmission signal is not received, and the transmission cycle (short transmission cycle) of the request signal when the transmission signal is received and when the reception strength is large is used. Door locks,
There is an effect that the response of the unlock can be further improved.

According to the invention described in claim 5 of the present invention,
In addition to the effect of the third aspect of the present invention, the portable device reduces the number of transmissions of the transmission signal when the reception strength of the request signal is greater than a second predetermined value (where the second predetermined value> the first predetermined value). I do.

For this reason, when the occupant is close to the vehicle and the necessity of improving the responsiveness is low (ie, when the reception strength of the request signal is larger than the second predetermined value), the number of transmissions is reduced to reduce power consumption. There is an effect that the power saving can be further improved.

According to the invention described in claim 6 of the present invention,
In addition to the effect of the second aspect of the present invention, the above-mentioned in-vehicle device lengthens the transmission cycle of the request signal when the reception intensity of the transmission signal is larger than the set value.

As a result, when the occupant is close to the vehicle and the necessity of improving the responsiveness is low (that is, when the reception strength of the transmission signal is larger than the set value), the transmission cycle is lengthened to give priority to power saving. Thus, there is an effect that the power saving can be further improved.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. The drawing shows a keyless entry system, FIG.
, The two-way communication type keyless entry system without switch operation comprises an on-vehicle device 1 for transmitting a request signal β, and a portable device 2 for transmitting a transmission signal α when the request signal β is received. The vehicle-mounted device 1 is configured to unlock or lock the door of the vehicle via the door lock actuator 3 according to the received electric field intensity (hereinafter simply referred to as received intensity) of the transmission signal α from the transmission signal α.

As shown in FIG. 2, the portable device 2 includes a battery 4, a transmitting / receiving antenna 5, and a timer 6, and the CPU 10 receives a request signal β from the transmitting / receiving antenna 5 according to a program stored in the ROM 7. , A timer 6, and a transmission / reception antenna 5, and a RAM 8 stores necessary data such as an in-vehicle device ID code and a map. Here, a portable device ID code is stored in the ROM 7 as unique identification information of the portable device 2.

On the other hand, as shown in FIG. 3, the on-vehicle device 1 has a transmitting / receiving antenna 9, a timer 11, a random number generator 12,
The CPU 20 includes a battery 13 and the like.
In accordance with the program stored in the ROM 14, the door lock actuator 3,
The drive of the timer 11, the random number generator 12, and the transmission / reception antenna 9 are controlled, and the RAM 15 stores necessary data such as an encryption code for a predetermined number of times and a map. Here, the ROM 14 stores an in-vehicle device ID code as unique identification information for identifying a vehicle.

As shown in FIG. 4, the request signal β has a data format having a start bit 16, an on-board unit ID bit 17, a random number bit 18, a time bit 19, a parity bit 21 (check bit), and an end bit 23. Be composed.

As shown in FIG. 5, the transmission signal α includes a star bit 23, an on-board unit ID bit 24, a portable unit ID bit 25, an encryption code bit 26, a parity bit 27 (inspection bit), and an end bit 28. It has a data format. The above cipher code bit 2
The encryption code No. 6 is formed by performing a predetermined operation (so-called processing) on the random number information and the time information of the request signal β.

FIG. 6 shows the RAM 8 (see FIG. 2) or the RAM 1
5 (see FIG. 3) is an explanatory diagram of the map M stored in FIG. 3, where the horizontal axis represents the reception intensity of the transmission signal α or the request signal β,
The vertical axis shows the parameters.

When the horizontal axis represents the reception intensity of the request signal β (in the case of the portable device), when the reception intensity is larger than the first predetermined value a, the number of transmissions N of the transmission signal α from the portable device 2 is performed.
Is set to be larger, and a second predetermined value b larger than the first predetermined value a is set, and the reception intensity of the request signal β is larger than the second predetermined value b (where b> a). At times, the number of transmissions N of the transmission signal α is set to be small.

In this embodiment, when the number of transmissions N is large, N = 2, and when it is small, N = 1.
The numerical value of the number of transmissions N is an example, and it goes without saying that the number of transmissions may be set to a number larger than this.

When the horizontal axis is the reception intensity J of the transmission signal α (in the case of the vehicle-mounted device), the transmission cycle Tβ of the request signal β when receiving the transmission signal α is set to a point P1 in FIG. 6 (when not receiving).
To point P2 (at the time of reception).

Further, as the reception strength J of the transmission signal α increases, the transmission period Tβ of the request signal β is set to be correspondingly shortened as shown by points P2 to P3.

Moreover, the transmission intensity J of the transmission signal α is equal to the set value c.
When it is larger than (predetermined threshold), point P
As shown between 3 and P4, the transmission period Tβ of the request signal β is set to be long.

In addition, as the reception strength J of the transmission signal α increases, as shown by the dotted line in FIG.
Is a map (storage means) that is set so that the transmission intensity Eβ becomes smaller in this order.

By the way, the CPU of the vehicle-mounted device 1 shown in FIG.
Reference numeral 20 denotes a transmission cycle changing means (refer to the fourth step A4 in the flowchart shown in FIG. 7) for shortening the transmission cycle Tβ of the request signal β from the point P1 to the point P2 in FIG. 6 when the transmission signal α is received. Transmission cycle shortening means for shortening the transmission cycle Tβ of the request signal β as shown by points P2 to P3 shown in FIG. 6 when the reception strength J of the signal is high (see the fourth step A4 in the flowchart shown in FIG. 7, in this embodiment, (Step A4 also serves as a transmission cycle changing means, a transmission cycle shortening means, and a next transmission cycle lengthening means), and the reception intensity J of the transmission signal α is set to a set value c (see FIG. 6).
The transmission period lengthening means (see the fourth step A4 in the flow chart shown in FIG. 7) for lengthening the transmission period Tβ of the request signal β when the value is larger than the threshold value is also used.

On the other hand, the CPU 10 of the portable device 2 shown in FIG.
Indicates that the reception intensity of the request signal β is the first predetermined value a (FIG. 6)
(See the sixth step B6 in the flowchart shown in FIG. 8), and the reception strength of the request signal β is set to a second predetermined value b (see FIG. 6). (Refer to the sixth step B6 in the flowchart shown in FIG. 8; in this embodiment, the step B6 is a transmission number decreasing means and a transmission number increasing means). And both means).

The operation of the keyless entry system configured as described above will be described in detail below with reference to flowcharts shown in FIGS. 7, 8, 9, and 10. First, a process of transmitting a request signal β from the on-vehicle device 1 to the portable device 2 will be described with reference to a flowchart shown in FIG.

In the first step A1 (reception determining means), the CP
U20 determines whether or not the transmission antenna 9 has received the transmission signal α within a predetermined time. If the determination is NO, the process proceeds to the second step A2, and if the determination is YES, another third step A3 is performed.
Move to

In the above-mentioned second step A2 (setting means), C
The PU 20 sets the reception strength J to zero, while the third
In step A3 (reading means), the CPU 20 reads the reception intensity J of the last transmission signal α.

Next, in a fourth step A4, the CPU 20 sets the transmission intensity Eβ of the request signal β and the transmission period Tβ from the map M of FIG. 6 according to the detected reception intensity J of the transmission signal α.

Next, in a fifth step A5 (elapse determination means),
The CPU 20 determines whether or not the set cycle (see the transmission cycle Tβ) has elapsed, and determines the next sixth step A only when YES is determined.
Move to 6.

In the sixth step A6 (random number generating means),
The CPU 20 drives the random number generator 12 to generate a random number (random number), and reads the vehicle-mounted device ID code from the ROM 14 in the next seventh step A7 (reading means). Next, in an eighth step A8 (request signal generating means), the CPU 20 reads the time from the timer 11, and generates a request signal β as shown in a data format in FIG. 4 based on the vehicle-mounted device ID code, the random number, and the time. create.

Next, in a ninth step A9 (request signal transmitting means), the CPU 20 sets the transmitting / receiving antenna 9 to the transmitting state, and transmits the above-described request signal β at the set transmission intensity Eβ. Next, in a tenth step A10 (encryption code creation means), the CPU 20 creates an encryption code for a predetermined number of times by a predetermined operation based on the random number and the time, and in a next eleventh step A11 (encryption code storage means).
0 stores the generated encryption code for a predetermined number of times in a predetermined area of the RAM 15.

Next, with reference to the flowchart shown in FIG. 8, the process of receiving the request signal β and transmitting the transmission signal α on the portable device 2 will be described. In a first step B1 (timing determination means), the CPU 10 determines whether or not a predetermined timing has been reached based on the time counted by the timer 6, and proceeds to the next second step B2 only when the determination is YES.

This second step B2 (reception detecting means)
The CPU 10 detects the reception of the request signal β, and in the next third step B3, the CPU 10
Determines whether or not has received the request signal β. When the determination is NO, the process returns to the first step B1, while YES
When the determination is made, the process proceeds to the next fourth step B4.

In the fourth step B4 (coincidence determining means),
The CPU 10 determines whether or not the vehicle-mounted ID code (see the vehicle-mounted device ID bit 17 shown in FIG. 4) in the request signal β matches the vehicle-mounted device ID code stored in the RAM 8 in advance. While returning to the first step B1, when the determination is YES, the process proceeds to the next fifth step B5.

In the fifth step B5 (intensity detecting means),
The CPU 10 detects the reception intensity of the request signal β.
The detection of the reception intensity can be performed by the antenna 5, but it goes without saying that a reception intensity detection sensor may be separately provided, and the same applies to the vehicle-mounted device.

Next, in the sixth step B6, the CPU 10 responds to the detected reception intensity of the request signal β in FIG.
The number of transmissions N of the transmission signal α is set to one or two times from the map shown in FIG.

Next, in a seventh step B7 (encryption code creation means), the CPU 10 determines the same operation equation as the operation equation in the previous tenth step A10 (see FIG. 7) based on the random number and the time in the request signal β. Create an encryption code with. Next, in an eighth step B8 (reading means), the CPU 1
0 reads the portable device ID code from the ROM 7, and reads the next ninth
In step B9 (transmission signal creating means), the CPU 10
Then, a transmission signal α as shown in the data format is created.

Next, in a tenth step B10 (transmitting signal transmitting means), the CPU 10 sets the transmitting / receiving antenna 5 to the transmitting state, and sets the generated transmitting signal α to the set number of transmissions N
To send. Next, with reference to a flowchart (main routine) shown in FIG. 9, a description will be given of a process on the vehicle-mounted device 1 that receives the transmission signal α and locks or unlocks the door keylessly.

First step S1 (timing determination means)
Then, the CPU 20 determines whether or not it is a predetermined timing, and
The process shifts to the next second step S2 only when S is determined. The predetermined timing in FIG. 9 is set to the same timing as the predetermined timing in FIG.

The above-mentioned second step S2 (reception detecting means)
Then, the CPU 20 detects the reception of the transmission signal α by the transmission / reception antenna 9. Next, in the third step S3 (determination means), the CPU
Reference numeral 20 executes a lock / unlock determination. This determination process will be described later with reference to a subroutine shown in FIG.

Next, in the fourth step S4 (determination means), the CP
U20 performs the determination of the determination result, and proceeds to the fifth step S5 when the lock is determined, and proceeds to the sixth step S6 when the unlock is determined.

In the above-mentioned fifth step S5 (locking means), C
The PU 20 drives the door lock actuator 3 to lock (lock) the door without a key. In the above-described sixth step S6 (unlocking means), the CPU 20 drives the door lock actuator 3 to key the door. To unlock (unlock).

Next, the lock / unlock determination processing corresponding to the third step S3 in FIG. 9 will be described with reference to a flowchart (subroutine) shown in FIG.
In a first step Q1 (reception determination means), the CPU 20 determines whether the transmission / reception antenna 9 has received the transmission signal α,
When the determination is YES, the process proceeds to the next second step Q2, while when the determination is YES, the process skips to the seventh step Q7.

The above-mentioned second step Q2 (coincidence determining means)
The CPU 20 determines the portable device ID code and the vehicle-mounted device ID code in the transmission signal α (see the portable device ID bit 25 and the vehicle-mounted device ID bit 24 shown in FIG. 5), the portable device ID code stored in the RAM 15, and the vehicle-mounted device ID. It is determined whether or not the codes match each other. If the determination is NO, the process skips to the seventh step Q7. On the other hand, if the determination is YES, the next third step Q3 is performed.
Move to

This third step Q3 (receiving intensity detecting means)
The CPU 20 detects the reception intensity J of the transmission signal α, and in the next fourth step Q4 (comparing means), the CPU 20 determines that the detected reception intensity J is equal to the first determination level J1 for unlock determination.
It is determined whether it is greater than or equal to. Thus, when J> J1
When (YES determination), the process proceeds to the fifth step Q5, where J <J
At the time of 1 (at the time of NO determination), the process shifts to another sixth step Q6.

In the above-described fifth step Q5 (unlock determination means), the CPU 20 executes an unlock determination corresponding to J> J1. On the other hand, in the above-described sixth step Q6 (comparing means), the CPU 20 determines whether or not the detected reception intensity J is smaller than a second determination level J2 (where J2 <J1) for lock determination, and makes a NO determination. At the time (when J> J2), the process is ended, while when the determination is YES (J <J2), the process proceeds to the seventh step Q7.

This seventh step Q7 (lock determination means)
Then, the CPU 20 executes the lock determination corresponding to J <J2. Thus, the contents of the determination shown in FIG. 10 are reflected in the main routine of FIG.

As described above, according to the keyless entry system shown in FIGS. 1 to 10 (an embodiment corresponding to claims 1 to 6), the above-mentioned on-vehicle device 1 transmits the request signal β at a predetermined cycle (see step A9). The portable device 2 having received the request signal β transmits the transmission signal α (see step B10).
The on-vehicle device 1 locks or unlocks the vehicle door according to the strength J when the transmission signal α is received, but the on-vehicle device 1 makes a request when receiving the transmission signal α (see YES determination in step A1). The transmission cycle Tβ of the signal β is shortened from the point P1 shown in FIG. 6 to the point P2 (see step A4).

Therefore, while the power saving is maintained by the transmission cycle Tβ of the request signal β when the transmission signal α is not received, the short transmission cycle Tβ of the request signal β when the transmission signal α is received (see the point P2). Lock the vehicle door at
There is an effect that the response of the unlock can be improved.

When the reception strength J (reception electric field strength) of the transmission signal α is large, the on-vehicle device 1 changes the transmission cycle Tβ of the request signal β as shown by points P2 to P3 in FIG. Shorten (see step A4).

As a result, while the power saving is maintained by the transmission cycle Tβ of the request signal β when the reception intensity J of the transmission signal α is not large, the transmission of the request signal β when the reception intensity J of the transmission signal α is large There is an effect that the response of locking and unlocking the vehicle door can be improved in the cycle Tβ.

Further, the portable device 2 increases the number of transmissions N of the transmission signal α when the reception intensity of the request signal β is larger than the first predetermined value a (see FIG. 6) (see step B6).

Therefore, while maintaining the power saving by the number of transmissions N of the transmission signal α when the reception intensity of the request signal β is equal to or less than the first predetermined value a, the reception intensity of the request signal β is set to the first predetermined value a. When the number of transmissions of the transmission signal α is larger than the number N, the responsiveness of locking and unlocking the vehicle door can be improved.

In addition, the above-mentioned on-vehicle device 1 shortens the transmission cycle Tβ of request signal β from point P1 to point P2 shown in FIG. 6 when receiving transmission signal α, and also has large reception strength J of transmission signal α. At this time, the transmission cycle Tβ of the request signal β is further shortened as shown by points P2 and P3 in FIG. 6 (see step A4).

As a result, while the power saving is maintained by the transmission cycle Tβ of the request signal β when the transmission signal α is not received, the transmission of the request signal β when the transmission signal α is received and when the reception strength J thereof is large. The cycle Tβ has the effect that the responsiveness of locking and unlocking the vehicle door can be further improved.

Further, in the above-described portable device 2, the reception intensity of the request signal β is equal to the second predetermined value b (where the second predetermined value b> first
When the value is larger than the predetermined value a), the number of transmissions N of the transmission signal α is reduced (see step B6).

Therefore, when the occupant is close to the vehicle and the necessity of improving the response is low (that is, when the request signal β
Is greater than the second predetermined value b), the number of transmissions N
Is reduced, and power saving is prioritized, whereby there is an effect that power saving can be further improved.

Further, when the reception strength J of the transmission signal α is greater than the set value c (see FIG. 6), the on-vehicle device 1 changes the transmission cycle Tβ of the request signal β to the points P3 to P4 in FIG.
(See step A4).

As a result, when the occupant is close to the vehicle and the necessity of improving the response is low (that is, when the reception strength J of the transmission signal α is larger than the set value c), the transmission cycle Tβ of the request signal β is lengthened. Thus, there is an effect that the power saving is prioritized, whereby the power saving can be further improved.

In the correspondence between the configuration of the present invention and the above-described embodiment, the number of transmissions N of the transmission signal α when the reception strength of the request signal β is greater than the first predetermined value a is:
The request signal β corresponds to two times in the embodiment, and similarly in the following.
The number of transmissions N of the transmission signal α when the reception intensity is larger than the second predetermined value b corresponds to one, but the present invention is not limited to the configuration of the above-described embodiment.

For example, the transmission cycle of the transmission signal α may be shortened when the signal strength of the request signal β is larger than a predetermined value on the portable device 2 side.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a keyless entry system of the present invention.

FIG. 2 is a control circuit block diagram of the portable device.

FIG. 3 is a block diagram of a control circuit of the vehicle-mounted device.

FIG. 4 is an explanatory diagram showing a data format of a request signal.

FIG. 5 is an explanatory diagram showing a data format of a transmission signal.

FIG. 6 is a transmission diagram of a map.

FIG. 7 is a flowchart showing a request signal transmission process on the vehicle-mounted device side.

FIG. 8 is a flowchart illustrating transmission signal transmission processing on the portable device side.

FIG. 9 is a flowchart showing lock and unlock control on the vehicle-mounted device side.

FIG. 10 is a flowchart showing lock / unlock determination processing on the vehicle-mounted device side.

[Description of Signs] 1 ... on-board unit 2 ... portable unit α ... transmission signal β ... request signal a ... first predetermined value b ... second predetermined value c ... set value

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Jun Okamitsu 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. (72) Inventor Junji Kanishi 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. (72) Inventor Toshifumi Adachi 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Pref.

Claims (6)

[Claims] 1. An in-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device is adapted to transmit a request signal to the vehicle door according to the reception strength of the transmission signal. A keyless entry system that does not require a switch operation for locking or unlocking a vehicle, wherein the in-vehicle device shortens a transmission cycle of a request signal when a transmission signal is received. 2. An in-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device is adapted to transmit a request signal to the vehicle door according to the reception strength of the transmission signal. A keyless entry system that does not operate a switch for locking or unlocking the keyless entry system, wherein the in-vehicle device shortens the transmission cycle of the request signal when the reception intensity of the transmission signal is high. 3. An in-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device is adapted to transmit a request signal to the vehicle door according to the reception strength of the transmission signal. A keyless entry system without a switch operation for locking or unlocking the keypad, wherein the portable device increases the number of transmissions of the transmission signal when the reception intensity of the request signal is greater than a first predetermined value. 4. An in-vehicle device for transmitting a request signal at a predetermined period, and a portable device for transmitting a transmission signal when the request signal is received, wherein the on-vehicle device is adapted to transmit a request signal to the vehicle door according to the reception strength of the transmission signal. A keyless entry system that does not operate a switch for locking or unlocking, wherein the in-vehicle device shortens the transmission cycle of the request signal when receiving the transmission signal and transmits the transmission cycle of the request signal when the reception strength of the transmission signal is high. Keyless entry system to further shorten. 5. The portable device according to claim 3, wherein a second predetermined value greater than the first predetermined value is provided, and the portable device reduces the number of transmissions of the transmission signal when the reception intensity of the request signal is larger than the second predetermined value. Keyless entry system. 6. The keyless entry system according to claim 2, wherein the on-vehicle device lengthens the transmission cycle of the request signal when the reception intensity of the transmission signal is greater than a set value.