JPS6314969A - Keyless entry apparatus - 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 [Field of Industrial Application] The present invention relates to a keyless entry device that controls the opening and closing of automobile doors and trunks using radio waves. This allows the door and the trunk to be opened and closed separately by button operation.

[Conventional technology]

A keyless entry system uses radio waves to remotely open and close the doors and trunk of a car without using a key, and uses a transmitter held by the person to open or close the door or open the trunk. A carrier wave modified with a code representing the operation and a specific code (identification number) corresponding to the tooth profile of the key is transmitted. When the receiver installed in the car receives the transmitted radio waves, it determines whether the identification number matches the one on the receiver side, and if it does, it determines the code representing the operation command and performs the control necessary for operation. Outputs a signal to drive an actuator to open and close the trunk or door lock.

In such systems, the transmitter is usually equipped with a switch for unlocking the door, a switch for closing the door, and a switch for unlocking the trunk. Send a code to open and close vehicle doors and trunk locks.

[Problem that the invention seeks to solve]

However, in the above-mentioned system, a person must select which switch to press, so it is easy to make a mistake in operation. The present invention attempts to improve this point by unifying the operation switch.

In this case, regarding the remote control range, if the person holding the transmitter is separated from the car, it is desirable to be able to operate it from all around the car in order to open the door for another person to get in. Considering that it is sufficient for the operator to operate the trunk near the trunk, the door can be opened and closed from around the car, and the trunk can only be opened when the transmitter is operated near the trunk. A keyless entry system is required.

[Means for solving problems]

The present invention provides a keyless entry device that transmits radio waves from a transmitter outside a vehicle to a receiver on the vehicle side to control opening or closing of a door or trunk of the vehicle. The receiver simultaneously transmits radio waves of two high and low frequencies, and when the receiver receives both types of waves at a predetermined level or higher, it controls the opening of the trunk, and when it receives only high frequency radio waves at a predetermined level or higher, it opens the door. It is characterized in that it controls opening and closing of the lock.

[Effect]

If the receiving antenna is installed on the car, several 10M
By using radio waves with a high frequency of Hz, it is easy to extend the remote control range to the entire circumference of the vehicle.

However, it is quite difficult to use the same frequency band to provide upward mobility only in a specific location, for example, to enable operation only in the vicinity of a trunk. This car body size is several tens of MH
It is speculated that because the wavelength is close to the Z band, the vehicle body, which is supposed to be a ground plate, is excited and reradiates to the original antenna element, or the excited vehicle body functions as an antenna element with the earth as the ground. Ru. For this reason, the sensitivity is not uniform around the entire circumference of the car,
This would also result in the trunk opening at other locations. However, if the frequency is chosen to be several 100 KHz, the arrival isolation will be shortened, but due to the propagation characteristics that it will be less affected by the car body (the car body will function as a ground plate), the antenna will have sensitivity only in one direction. This makes it easier to

FIG. 1 is an explanatory diagram of this, where (al indicates a 60 MHz isoelectric field line, and (b) indicates a 500 KHz isoelectric field line.

In the diagram, 1 is the vehicle body, 2 is the door, 3 is the trunk, and 4 is 60M
The Hz band antenna 5 is a 500 KHz band antenna. The antenna 4 can be used in common with, for example, an FM band radio antenna (glass antenna, Rondo antenna). The antenna 5 is, for example, a ferrite bar with a coil wound around it.
For example, it can be attached to the rear bumper.

(a) (Using the characteristics of BL, transmits radio waves of 60 MHz and 500 KHz at the same time, and when only 60 MHz is received at a predetermined level or higher, controls the opening and closing of door 2,
If the trunk 3 is controlled to open when both 0MHz and 500KHz are received at a predetermined level or higher, the door control area and trunk control area will be wide (like 6 and 7 of C1).
The doors 2 are narrowly separated and can be opened and closed from all directions, but the trunk 3 can only be opened when approaching the rear.

〔Example〕

FIG. 2 is a block diagram showing an embodiment of the present invention, where (al is a transmitter and fb) is a receiver. The transmitter 8 operates at 60 MHz (f
+) and 500 KHz (f2) self-excited or crystal oscillator-based oscillation circuits 82.83, and transmit radio waves of each frequency from antennas 84.85. However, the output is weak, about 15μV/m at 100m away. This transmitter's unique identification code has a wide reception area.
Modulation on the 1 side is easier to detect. 86 is a code generation section for this purpose.

The receiver 9 has a receiving section 90.91 that receives f+ and f2 using an antenna 4.5, and a code discriminating section 92 detects a code from the output of the receiving section 90.

Further, the door level determination circuit 93 determines whether the output of the receiving section 9o is equal to or higher than a predetermined value (referred to as a door level), and the trunk level determination circuit 94 determines whether the output of the receiving section 91 is equal to or higher than a predetermined value (referred to as a trunk level). Determine if it is. 95 is a circuit that gives priority to the trunk level from the outputs of both discrimination circuits. In other words, if the output A of the discrimination circuit 93 when f: is detected is 1, and the output B of the discrimination circuit 94 when f: is detected is 1, then as shown in FIG. °B=O, and in region 7, A=1.B=1.

Therefore, the required control details are as follows.

Table 1 96 shows a door/trunk opening/closing control circuit that controls the actuator 93 or 99 by referring to the output of the priority circuit 95 and the door opening/closing detection circuit 97 when the output C of the code discrimination section 92 is 1 (match). In this case, since the trunk lock is always controlled only to open, actuator 9 is activated every time.
However, in the case of a door lock, it is necessary to reverse the state so that if it is open, it is closed, and if it is closed, it is open. to drive.

〔Effect of the invention〕

As described above, according to the present invention, only one button is required for the transmitter in order to distinguish the control content depending on the position of the transmitter, and by using frequencies with different propagation characteristics such as 500 KHz and 60 MHz, an accurate determination area can be obtained. There are advantages that can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention, and FIG. 2 is a configuration showing an embodiment of the present invention. In the figure, 1 is the vehicle body, 2 is the door, 3 is the trunk, 4° 5 is the reception antenna, 6 is the door control area, 7 is the trunk control area, 8 is the transmitter, 9 is the receiver, 81 is the transmission switch, 82
．． 83 is a transmitting circuit, 90.91 is a receiving section, 93 is a door level discrimination circuit, 94 is a trunk level discrimination circuit, 96 is a door/trunk opening/closing control circuit, and 98.99 is an actuator. Applicant Fujitsu Ten Ltd. Representative Patent Attorney Minoru Aoyagi (0) 60M)-1zノW1! Kai a
(b) 500Hz'y*external line (C) Door/)
? )'11 X'1t21]%i5: Figure 1

Claims (1)

[Claims] In a keyless entry device that controls opening or closing of a door or trunk of a vehicle by transmitting radio waves from a transmitter outside the vehicle to a receiver on the vehicle side, the transmitter can simultaneously control two high and low positions with a single switch operation. When the receiver receives both radio waves at a predetermined level or higher, it controls the opening of the trunk lock, and when it receives only the high-frequency radio wave at a predetermined level or higher, it controls the door lock. A keyless entry device characterized by: