JP3597670B2 - Automotive body approach detection sensor - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an automobile human body approaching detection sensor for detecting a human body approaching an automobile.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as an automobile security system, a system that recognizes a user by transmitting and receiving a user identification code between a key device carried by the user and a vehicle side is known. As a trigger unit for executing this user identification process, Some have a proximity sensor.
[0003]
With the above-described system, for example, when the proximity sensor detects that the user is approaching, a confirmation by transmitting and receiving a user identification code is performed, and when it is confirmed that the user is an authorized user, the door lock is unlocked. Operability can be improved.
[0004]
By the way, as a proximity sensor used as this type of sensor, there are a sensor based on a pyroelectric infrared sensor, a sensor based on an infrared reflective sensor, a sensor based on an ultrasonic reflective sensor, and the like. And a pressure switch by a piezoelectric element.
[0005]
[Problems to be solved by the invention]
However, there is a problem that the space efficiency of the sensor is inferior because a mounting space for the sensor is required, and that the sensor using the piezoelectric element or the ultrasonic element is expensive as described above, and that the sensor structure is complicated. .
[0006]
[Means for Solving the Problems]
In order to solve such a problem and reduce the cost of a human body approach detection sensor for an automobile, the present invention provides a sensor for human body approach discrimination using a sensor that detects a human body approaching an automobile in a non-contact manner. Wherein the sensor comprises a parallel cable received in the hollow handle of the door handle so as to extend in a longitudinal direction, and the sensor changes according to a difference in a distance of the human body to the handle. Detecting the approach of the human body by a change in the capacitance of the parallel cable , wherein the door handle is provided integrally with a circuit board having a circuit for detecting the change in the capacitance. did.
[0007]
As described above, the parallel cable is used as a sensor for detecting the difference in the distance from the human body in a non-contact manner, and the parallel cable is received in the hollow grip portion of the door handle so that the user can place the door. The function as a proximity sensor for detecting that the user has approached the door handle to open the door can be exhibited by the change in the capacitance of the parallel cable.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail based on specific examples shown in the accompanying drawings.
[0009]
FIG. 1 is a cutaway view of an automobile door handle to which the present invention is applied. In the drawing, a door handle base 1 is screwed to a door (not shown), and one longitudinal end of an outer handle 2 is pivotally supported by the base 1 so that the door handle tilts with respect to the door so as to be protruded and retracted. An outer handle 2 is provided.
[0010]
On the inner surface side of the door when the base 1 is mounted, a circuit board 3 for performing a main part of control of the present apparatus is provided in a case 4 screwed to the base 1 so as to be protected by urethane resin. Have been. Although the case 4 is formed separately from the base 1 in the illustrated example, it may be formed integrally with the base 1.
[0011]
The outer handle 2 is formed in a hollow shape as shown in the figure by, for example, gas injection molding, and a parallel cable 5 constituting a capacitance-type sensor as a non-contact sensor is provided in the hollow portion. The grip portion is received so as to extend along the longitudinal direction. One end (base end) of the parallel cable 5 is connected to a shield wire 6 provided so as to extend to the outside via an opening provided near the pivot of the outer handle 2. The other end of the shield wire 6 is connected to the circuit board 3. In addition, it is good to use the gas inlet at the time of gas injection molding for the above-mentioned opening, and wiring can be processed very suitably. A seal member 7 for waterproofing the inside of the outer handle 2 is attached to the opening, and the seal member 7 is configured to be sealed with an O-ring or with an adhesive. Is also good.
[0012]
An external connection cable 8 is connected to the circuit board 3, and a coupler 9 attached to an extension end of the external connection cable 8 is connected to an external control unit 10. A transmission / reception antenna 11 is connected to the external control unit 10 so that a user recognition signal is exchanged with a transmission / reception device built in the key device 12 owned by the user. Note that user recognition data is stored in the external control unit 10 in advance, and if the stored data matches the signal data from the key device 12, the user is recognized as a legitimate user, and subsequent processing is performed.
[0013]
Next, a human body approach discrimination circuit according to the present invention will be described below with reference to the schematic diagram of FIG. As shown in FIG. 2, a power supply voltage is supplied from a vehicle-mounted battery BT to a circuit board 3 of the device via a power supply circuit VC, and one of the parallel cables 5 is connected to the power supply line. 5a is connected. The other line 5b of the parallel cable 5 is grounded via a resistor R1 provided on the circuit board 3, and the node between the other line 5b and the resistor R1 is provided in parallel with each other via a capacitor C1. Connected to the comparators CP1 and CP2 of the proximity detection circuit 3a and the proximity detection circuit 3b, respectively.
[0014]
A capacitance change occurs between the two lines 5a and 5b of the parallel cable 5 connected as described above in accordance with the approach of the human body, and the change is generated on the ground side line 5b by the voltage change of each comparator CP1.・ Detect with CP2. Since the voltage level at the input stage to each of the comparators CP1 and CP2 is different between the state where the person (hand) approaches and is near and the state where the person (hand) is near and close when the outer handle 2 is touched or gripped. In order to discriminate and detect the voltage level in each state, each detection level of each of the comparators CP1 and CP2 as the first and second thresholds is adjusted by the respective threshold adjustment resistors VR1 and VR2. Keep it. Therefore, each threshold value can be changed according to the type of vehicle according to the shape of the outer handle for each type of vehicle, so that it is possible to easily cope with different types of vehicle.
[0015]
Note that the threshold value for detecting proximity may be such that it detects that a person has entered a range in which signals of recognition data can be transmitted and received with the key device 12 owned by the user. Further, as the threshold value for the closest detection, it is preferable to detect a state in which the outer handle 2 is gripped by hand.
[0016]
When each of the above-mentioned states is detected by each of the comparators CP1 and CP2, a signal is output from each of the comparators CP1 and CP2 to the corresponding waveform shaping circuit WC1 and WC2. The signals amplified by AP1 and AP2 are output from the proximity determination output terminal N and the proximity determination output terminal T, respectively.
[0017]
For example, in the case of the automobile in the illustrated example, when it is detected that a person is approaching, a proximity detection signal is output from the proximity determination output terminal N, and the key unit 12 is output by the external control unit 10 according to the proximity detection signal. A request signal is issued to the user, and in response to the request signal, a user recognition signal issued from the key device 12 is determined. When the user recognition signal is recognized as an authorized user, a room lamp (not shown) of the vehicle is turned on to notify a person approaching. Notifies that control by the device is possible. Thus, a warning can be issued to a person who illegally uses the access.
[0018]
Next, when it is detected that the outer handle 2 is gripped for opening the door, a proximity detection signal is output from the proximity determination output terminal T, and control for releasing the door lock is performed.
[0019]
In this manner, the detection that a person has approached the vehicle and the detection that the person has touched the outer handle 2 can be detected by one sensor (capacitive sensor using the parallel cable 5). It is not necessary to separately provide the proximity sensor and the contact sensor as in the above, and the apparatus can be reduced in cost.
[0020]
In addition, as a whole control, the user recognition may be performed at the time of the latest detection. When the room lamp is turned on by the proximity detection and a person who comes close to the room just leaves, a timer or a CPU (not shown) may be used. It is preferable to stop the room lamp lighting output after a predetermined time elapses and to return to the initial state by the timer processing. Then, in that case, it is desirable to reset the user recognition.
[0021]
In the illustrated example, the circuit board 3 is provided integrally with the door handle. However, as shown in FIG. 3, the control unit 13 provided with the circuit board may be provided separately from the door handle. Note that, in FIG. 3, the same parts as those in the illustrated example are denoted by the same reference numerals, and detailed description thereof will be omitted. In the case of FIG. 3, a shielded wire is used for the transmission cable 14 connecting the parallel cable 5 as a sensor and the control unit 13. Thus, the influence of the metal body on the change in the capacitance of the sensor (parallel cable 5) can be eliminated. Further, in the present embodiment, an example in which the parallel cable is used as the proximity sensor and the contact sensor has been described, but it is also possible to use the parallel cable only as the proximity sensor or only as the contact sensor.
[0022]
【The invention's effect】
As described above, according to the present invention, since the parallel cable extends and is provided in the outer handle formed in a hollow shape, it is not necessary to provide a special installation space for the sensor, and the sensor structure can be simplified. Can be achieved, and the entire apparatus can be inexpensive.
[Brief description of the drawings]
FIG. 1 is a cutaway view of an automobile door handle to which the present invention is applied.
FIG. 2 is a diagram schematically showing a human body approach discrimination circuit according to the present invention.
FIG. 3 is a view showing a door handle and a control unit for an automobile according to another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base 2 Outer handle 3 Circuit board, 3a Proximity detection circuit, 3b Proximity detection circuit 4 Case 5 Parallel cable, 5a / 5b wire 6 Shield wire 7 Seal member 8 External connection cable 9 Coupler 10 External control unit 11 Transmission / reception antenna 12 Key device 13 Control unit 14 Transmission cable

Claims (1)

A human body approaching discrimination sensor using a sensor that detects a human body approaching a car in a non-contact manner,
The sensor comprises a parallel cable received in a hollow shape formed in a door handle and extending longitudinally in the grip, and the parallel cable changes according to a difference in a distance of the human body to the grip. Detecting the approach of the human body by a change in capacitance ,
A human body approach detection sensor for an automobile , wherein a circuit board having a circuit for detecting a change in the capacitance is provided integrally with the door handle .

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