JP3398714B2 - Electrode connection structure of occupant detection sensor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode connection structure for an occupant detection sensor, and more particularly to an electrode (antenna electrode) for the occupant detection sensor and a dedicated cable for the occupant, which are arranged on a seat to detect a seating condition of an occupant. Related to the improvement of the connection structure.

[0002]

2. Description of the Related Art Generally, an airbag device is a device for alleviating an impact on an occupant in a vehicle collision.
It has become indispensable for the safety of automobiles, and in recent years, it has been installed not only in the driver's seat but also in the passenger seat. For this reason, even if a vehicle collides, the occupant not only in the driver's seat but also in the passenger seat can be protected from the impact due to the collision by the expanding operation of the airbag device.

In a vehicle equipped with such an air bag device, an occupant detection sensor for detecting whether or not an occupant is seated is installed in the passenger seat, and the passenger seat detection sensor detects whether the occupant is seated in the passenger seat. There has been proposed an occupant detection system that determines the seating status of an occupant and sets the airbag in either a deployable state or an undeployable state when a vehicle collides. As the occupant detection sensor of this occupant detection system, a weight sensor that measures the weight of the occupant is used, and the occupant seated in the seat is photographed by a camera and image processing is performed to determine whether or not the occupant is present, the seating status, and It has been proposed to determine whether a child or a child.

In the occupant detection system using the former weight sensor, it is possible to roughly judge whether the occupant in the passenger seat is an adult or a child. Based on the result of the judgment, the airbag can be deployed or cannot be deployed. Although it can be set to either one of these conditions to avoid an unexpected situation at the time of a car collision, there are large individual differences in weight and even children and even adults may be heavier, so the accuracy is Lack. In the case of the latter occupant detection system using a camera, it is possible to fairly accurately determine the occupant's seating status, whether the occupant is an adult or a child, and whether the child in the child seat is facing forward or backward. However, the seating condition pattern must be determined from various data obtained by performing image processing on the image data captured by the camera, which causes a problem that the processing device becomes complicated and expensive.

Therefore, the present applicant previously proposed an occupant detection system capable of solving such a problem. The basic principle of this proposal is basically to use the disturbance of the weak electric field (Electric Field) generated in the antenna electrode arranged in the sheet or the like. Specifically, it is arranged in the sheet. A weak electric field is selectively generated around the plurality of antenna electrodes, and the seating condition of the occupant is seated based on the electric current flowing through each antenna electrode due to the electrical characteristics of the object located in the vicinity of these antenna electrodes. It detects the presence / absence of seats, whether an occupant is an adult or a child, etc.
In particular, if the number of antenna electrodes is increased, it becomes possible to obtain much information about the occupant on the seat, etc., and occupant detection can be performed more accurately.

An occupant detection system utilizing this principle will be described with reference to FIGS. The seat 1 of the passenger seat shown in FIG. 8 has a seating portion 1a and a backrest portion 1b, and an occupant detection sensor 3 is arranged in the seating portion 1a and the backrest portion 1b. The occupant detection sensor 3 is made flexible in consideration of the sitting comfort of the occupant, and a plurality of conductive antenna electrodes 5 are fixed to one surface of the base member 4 such as non-woven fabric by pasting or stitching. It was done. For the antenna electrode 5, for example, thread-like metal is woven into cloth,
The cloth is coated with a conductive paint, and each antenna electrode 5 is wired with a signal processing circuit 8 of the control unit 7 and a dedicated cable 6 as shown in FIG.

The control unit 7 has a signal processing circuit 8 and its power supply circuit (not shown) built in one housing, and is installed in a base 1c for supporting the seat 1. The signal processing circuit 8 has a frequency of 100 KHz on each antenna electrode 5 via the switching element 9 and the cable 6.
Apply a high frequency low voltage of about 5 to 12V,
The occupant seating situation data is calculated by processing the signal data relating to the current flowing based on the weak electric field of each antenna electrode 5. The cable 5 is, for example, a shielded cable including a signal line and a shield wire that shields the signal line. The cable 5 shields transmission / reception signals between the antenna electrode 5 and the signal processing circuit 8 from external noise, and performs signal processing by the signal processing circuit 8. Increase accuracy.

The signal processing circuit 8 calculates the seating pattern of the passengers in the seat 1 by arithmetically processing various seating status data representing the seating status of the occupants in various parts of the seat 1. The signal processing circuit 8 stores various seating patterns and the like in advance, and compares the seating patterns calculated from the input data with the stored seating patterns and the like. The seating patterns and the like to be extracted are extracted and determined. The seating pattern stored in the signal processing circuit 8 is, for example, an empty seating pattern in which no occupant is seated in the seat, a pattern in which an adult is normally seated in the seat,
For example, a pattern in which a child is seated in a seat. When the seating pattern is detected and specified by the signal processing circuit 8, a signal based on the seating pattern is transmitted from the signal processing circuit 8 to, for example, an airbag device (not shown), so that the automobile may collide with the airbag device. Even so, a signal for setting so that the airbag does not deploy is transmitted, or a signal for setting so that the airbag deploys.

[0009]

The occupant detection sensor 3 has a plurality of cloth-like antennas having conductivity on the front surface (or back surface) of one base member 4 as shown in FIG. 10, for example. The electrodes 5 are arranged in a predetermined array pattern, and the tip end of the cable 6 is electrically and mechanically connected to each antenna electrode 5 via a dedicated connection terminal 10. The connection terminal 10 is of a hook type or a pin type which is caulked and fixed to the antenna electrode 5 and the base member 4. However, since the cloth-shaped antenna electrode 5 and the base member 4 such as a non-woven fabric cannot be unnecessarily thickened from the viewpoint of comfort of sitting on the seat, the antenna electrode 5 of the connection terminal 10 is not provided. Also, the mechanical connection strength and the contact area with the base member 4 are insufficient, and the durability is also insufficient.
Therefore, if the occupant detection sensor 3 is attached to a seat or the like and an external force is applied when the occupant is seated, the electromechanical connection between the antenna electrode 5 and the cable 6 may be impaired, which causes a problem in reliability. It was

Therefore, an object of the present invention is to provide an electrode connection structure of an occupant detection sensor for connecting a cable to a conductive cloth-shaped antenna electrode formed on a base member with stable electric and mechanical strength. To provide.

[0011]

The technical means for accomplishing the above object of the present invention is to provide a passenger detection sensor in which a conductive antenna electrode is arranged on one surface of a base member.
And the antenna electrode of the occupant detection system in the occupant detection system that processes the current signal flowing through the antenna electrode by the signal processing circuit based on the electric field generated around the antenna electrode to detect the seating condition of the occupant. A cable connection structure, in which a desired portion of the antenna electrode is
The extending electrode portion extending in the peripheral direction of the base member is folded back to the other surface of the base member, and the antenna electrode on one surface of the base member and the base member are folded back at this folded portion. The connecting terminal is electrically and mechanically connected to the overlapping portion with the existing electrode portion, and the cable is electrically connected to the connecting terminal.

According to a second aspect of the present invention, the connecting terminal is formed on the overlapping portion of the antenna electrode on one surface of the base member, the base member and the folded extension electrode portion, and the same overlapping portion. It is characterized in that it is electrically and mechanically connected by being penetrated and pinched, and a cable is electrically connected to a part of the connection terminal.

Here, in the overlapping portion where the antenna electrode on one surface of the base member in the occupant detection sensor, the base member and the folded extension electrode portion overlap, the upper and lower layers are the antenna electrode and the folded extension electrode portion. The intermediate layer is a part having a large mechanical strength in the three-layer structure in which the intermediate layer is a base member. Therefore, the connecting terminal can be attached to the overlapping portion with sufficient mechanical strength, and the cable can be attached to the connecting terminal with sufficient electromechanical strength. Further, the upper and lower surfaces of the overlapped portion are the electrode surface of the antenna electrode and the folded and extended electrode portion thereof, and by electrically connecting the connecting terminals to the upper and lower electrode surfaces, the electrical connection area is expanded and the antenna electrode And the electrical connection area of the connection terminal and the cable is increased.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Various embodiments of the present invention will be described with reference to FIGS. It should be noted that each of the embodiments in the same figure shows an occupant detection sensor 3 in the occupant detection system of FIGS.
This is applied to the connection structure of the cable 6 and the cable 6, and the same or corresponding portions are denoted by the same reference numerals and detailed description thereof will be omitted.

The electrode connecting structure of the first embodiment shown in FIGS. 1 (a) and 1 (b) is a cloth-like antenna having conductivity which is arranged on one surface of the base member 4, for example, the surface. Electrode 5
The extended electrode portion 5a extending from a part of the peripheral edge of the base member 4 is folded back to the back surface (the other surface) of the base member 4, and the folded extended electrode portion 5a, the antenna electrode 5, and the base member 4 are joined together. The cable 6 is electrically and mechanically connected to the overlapping portion m which is overlapped with the layer via the connection terminal 11. In FIG. 1, the connecting terminal 11 is electrically and mechanically coupled to the overlapping portion m,
An embodiment is shown in which the cable 6 is electromechanically coupled to the.

For example, in the case of manufacturing the occupant detection sensor 3 by attaching a plurality of rectangular conductive cloth-shaped antenna electrodes 5 to the peripheral portion of the surface of the base member 4 such as a rectangular nonwoven fabric by sticking or thermocompression bonding. As shown by the chain line in FIGS. 2 and 3, an extended electrode portion 5a is integrally formed in the central portion of the outer peripheral edge of the antenna electrode 5, and the extended electrode portion 5a is formed from the end of the base member 4 to the back surface. Fold back to and fix it on the back by pasting or thermocompression bonding. The extended electrode portion 5a folded back on the back surface of the base member 4 is superposed on a part of the antenna electrode 5 on the surface of the base member 4 to form the antenna electrode 5, the base member 4, and the folded extended electrode portion 5a. The connection terminal 11 is fixed to the overlapping portion m, and the tip portion of the cable 6 is connected to the connection terminal 11.

The connection terminal 11 is electrically and mechanically bonded to the overlapping portion m by a crimping force or elastic force, and is, for example, a one-touch type elastic terminal for elastically holding the overlapping portion m from above and below. A specific example is shown in FIG. Connection terminal 11 in FIG.
Is composed of a pair of a first stopper 12 and a second stopper 13 made of metal. The first stopper 12 has a structure in which the pin portion 12b is projected from the center of the lower surface of the circular push plate portion 12a, and the locking portion 12c is projected on the outer periphery of the tip end portion of the pin portion 12b. The second stopper 13 is shown in FIG. 4, which is an annular disc spring, and has an outer diameter of an annular electrode pressing portion 13a and an electrode pressing portion 13a having the same outer diameter as that of the pressing plate portion 12a of the first stopper 12. A plurality of tongue-shaped spring portions 13b extending obliquely from the inner peripheral edge toward the central portion, and a cable connecting portion 13c integrally extending from a part of the outer peripheral edge of the electrode pressing portion 13a. To be done.
The tip portion of the cable 6 is electromechanically caulked and fixed to the cable connection portion 13c by using a crimp terminal 14 having a well-known sleeve shape or the like.

The connection terminal 11 consisting of a pair of first and second stoppers 12 and 13 has an occupant detection sensor 3 as shown in FIG.
Is attached to the overlapping portion m of Overlapping part m
A mounting hole 15 through which the pin portion 12b of the first stopper 12 is inserted is previously formed in a part of the first stopper 12, and the first side is formed from the surface side of the overlapping portion m.
The pin portion 12b of the stopper 12 is penetrated through the mounting hole 15, and the locking portion 12c is projected to the back surface side of the overlapping portion m. In this state, from the back surface side of the overlapping portion m, the spring portion 13 of the second stopper 13 is
b is press-fitted into the pin portion 12b of the first stopper 12, and the spring portion 1
The tip of 3b is elastically locked to the locking portion 12c of the pin portion 12b. At this point, the overlapped portion m is elastically clamped from above and below by the pressing plate portion 12a of the first stopper 12 and the electrode pressing portion 13a of the second stopper 13.

The first and second stoppers 12, 13 as described above
The attachment to the overlapping portion m is performed by a one-touch method in a simple and quick manner. In each of the attachments 12 and 13 attached in this manner, the first attachment 12 comes into elastic contact with the antenna electrode 5 on the surface of the base member, Since the second stopper 13 is in elastic contact with the folded and extended electrode portion 5a on the back surface of the base member, the substantial electrical contact area of the connection terminal 11 with the antenna electrode 5 increases. Moreover, the overlapping portion m is the antenna electrode 5 and the base member 4.
Since the three layers of the folded and extended electrode portion 5a are superposed portions having high mechanical strength, the connecting terminal 11 is connected to the superposed portion m.
Can be mounted with stable mechanical strength. Further, the cable 6 is crimped and fixed to the second stopper 13 with the crimp terminal 14,
The electrical and mechanical connection strength between the connection terminal 11 and the cable 6 is made stable. Therefore, the cable 6 is always connected to the antenna electrode 5 of the occupant detection sensor 3 through the connection terminal 11 in the electrically stable state with a high mechanical strength.

Next, another embodiment of the present invention will be described with reference to FIGS. 5 to 7. The second embodiment shown in FIG.
This is different from the first embodiment in that the electrode pressing portion 13a ′ of the first second stopper 13 ′ has a flat plate shape. By thus forming the electrode pressing portion 13a ′ into a flat plate shape, the folded back extended electrode portion 5a
It becomes easy to enlarge the contact area with and it becomes easy to form various shapes such as a rectangle and a circle in correspondence with the shape of the folded back extension electrode portion 5a.

In the third embodiment shown in FIG. 6, the first stopper 12 of the connection terminal 11 is fixed to the overlapping portion m via the lug terminal 16, and the cable 6 is electrically and mechanically connected to the lug terminal 16. It is a thing. Since the lug terminal 16 is pressed against the antenna electrode 5 by the push plate portion 12a of the first stopper 12 and is electrically and mechanically connected, the antenna electrode 5 and the cable 6 have stable strength and a large electrical contact area. Connected by.

FIG. 7 shows an example of changing the shape of the antenna electrode 5 on the surface of the base member 4 and its extending electrode portion 5a. The extending electrode portion 5a shown in FIG. The rectangular antenna electrode 5 has a small width and extends from the end of the antenna electrode 5 with a width half the width of the antenna electrode 5. The extended electrode portion 5a shown in FIG. 7 (b) extends from the end of the antenna electrode 5 having a smaller width with the same width. The width of the extended electrode portion 5a is changed according to the number, width, shape, and arrangement pattern of the antenna electrodes 5 in one base member 4.

The present invention is not limited to the above-described embodiment. For example, the connection terminal is composed of the first and second stoppers, and the pin portions of the first stopper are pressed and deformed to be superposed. Can be attached to a part,
It is also possible to combine the lug terminals of the above embodiments. Besides the cloth-like base member, a sheet member having an insulating property can be used. Further, in addition to caulking, welding, welding, soldering and the like can be applied to the electromechanical connection between the connection terminal and the cable. Moreover, the number of antenna electrodes may be one instead of being plural. Furthermore, the occupant detection sensor according to the present invention can be applied not only to occupant detection based on a signal obtained only by transmission, but also to an occupant detection system by a combination of transmission and reception.

[0024]

According to the present invention, an antenna electrode of an occupant detection sensor including a base member and an antenna electrode having conductivity, and a base member and an extended electrode portion of the antenna electrode are overlapped with each other. Since the cable is connected via the connection terminal, the connection terminal can be connected to the antenna electrode and its extended electrode portion with a large electric contact area and mechanical strength,
An electrode connection structure for an occupant detection sensor having excellent durability and reliability can be provided, and the reliability of an occupant detection system for an automobile using the occupant detection sensor can be improved.

In particular, if the connection terminal used for the electromechanical connection with the antenna electrode is a connection terminal having a structure of penetrating the overlapping portion of the occupant detection sensor and holding it elastically, the connection terminal and the occupant detection sensor are connected. The electromechanical connection strength of the polymerized portion is further improved and becomes stable.

[Brief description of drawings]

1A and 1B are views showing a first embodiment of an electrode connection structure of an occupant detection sensor according to the present invention, in which FIG. 1A is a plan view and FIG. 1B is a line AA in FIG. 1A. Enlarged sectional view.

FIG. 2 is an exploded cross-sectional view of the electrode connection structure of FIG.

3 is a partial plan view of an occupant detection sensor in the electrode connection structure of FIG.

4 is a plan view of a connection terminal and a cable in the electrode connection structure of FIG.

FIG. 5 is a sectional view of the second embodiment of the present invention.

FIG. 6 is a sectional view of a third embodiment of the present invention.

FIG. 7 is a partial plan view of an antenna electrode in an occupant detection sensor for explaining fourth and fifth embodiments of the present invention.

FIG. 8 is a perspective view of a seat on which an occupant detection sensor used in the occupant detection system according to the present invention is installed.

9 is a circuit block diagram of an occupant detection system installed on the seat of FIG.

FIG. 10 is a perspective view showing an electrode connection structure of a conventional occupant detection sensor.

[Explanation of symbols]

1 sheet 3 Occupant detection sensor 4 base members 5 antenna electrodes 5a extended electrode section m polymerized part 6 cables 8 Signal processing circuit 11 connection terminals 12 First stop 12a Push plate part 12b Pin part 12c Locking part 13, 13 'Second stopper 13a, 13a 'electrode pressing portion 13b Spring part 13c cable connection 14 Crimp terminal 15 mounting holes 16 lug terminals

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tsutomu Fukui               1-4-1 Chuo, Wako-shi, Saitama Stock               Honda R & D Co., Ltd. (72) Inventor Nobuhiro Koyoda               1-4-1 Chuo, Wako-shi, Saitama Stock               Honda R & D Co., Ltd. (72) Inventor Takashi Ino               1-4-1 Chuo, Wako-shi, Saitama Stock               Honda R & D Co., Ltd. (72) Inventor Issei Isashin               1-4-1 Chuo, Wako-shi, Saitama Stock               Honda R & D Co., Ltd.                (56) References JP-A-64-10580 (JP, A)

Claims (5)

(57) [Claims] 1. An occupant detection sensor having a conductive antenna electrode arranged on one surface of a base member is arranged on a seat, and a current signal flowing through the antenna electrode based on an electric field generated around the antenna electrode. Is a connection structure of an antenna electrode and a cable of an occupant detection sensor in an occupant detection system that processes a signal processing circuit to detect an occupant's seating situation, and the desired portion of the antenna electrode extends in the peripheral direction of the base member. The extended electrode portion formed by folding back to the other surface of the base member, and the connection terminal is formed in the folded portion at the overlapping portion of the antenna electrode on one surface of the base member, the base member and the folded extended electrode portion by an electric machine. Electrode connection structure of an occupant detection sensor, characterized in that the cable is electrically connected to the connection terminal and a cable is electrically connected to the connection terminal. 2. The connection terminal is electrically and mechanically connected to the overlapping portion of the antenna electrode on one surface of the base member, the base member and the folded extension electrode portion by penetrating and sandwiching the overlapping portion. The electrode connection structure for the occupant detection sensor according to claim 1, wherein a cable is electrically connected to a part of the connection terminal. 3. The connection terminal includes the antenna electrode and
And the folded and extended electrode portions are elastically contacted with each other, and
It is equipped with a pair of stoppers that hold the joint
An electrode for pressing the folded-back extending electrode portion side of the pair of stoppers.
The pole pressing portion has a flat plate shape.
The electrode connection structure of the onboard occupant detection sensor. 4. The connection terminal is connected to a cable by an electric machine.
Lug terminal that is electrically connected to the lug terminal
Characterized in that it is provided with a stopper for pressing the minute.
The electrode connection structure for the occupant detection sensor according to claim 1. 5. The connection terminal includes the antenna electrode and
And a pair of elastically contacting the folded and extended electrode portions.
It is equipped with a stop and this pair of stops is installed on one side.
Elastically sandwiching the overlapping portion with a spring
The electrode contact of the occupant detection sensor according to claim 1,
Continued structure.