JP2001080402A - Occupant detection device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable a sensor of an occupant detection device for detecting the physique and posture of an occupant seated on a seat to be easily and securely fixed to a seat back. A sensor body includes a first protective layer made of a resist paste layer, an antenna film made of a PET film, and a first conductor layer made of a silver layer.
2, a second conductor layer 43 made of a carbon layer, a second protective layer 45 made of a resist paste layer, and a hot melt film 46 are sequentially laminated. When the hot melt film 46 of the sensor main body 31 is pressed against the front surface of the wadding 21 previously bonded to the pad of the seat back and heat pressed, the sensor main body 31 is bonded by the adhesive force generated by the molten hot melt film 46. 21
Firmly and securely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant detection device having a seat-shaped sensor fixed to a seat back in order to detect an occupant's sitting posture and physique.

[0002]

2. Description of the Related Art When a child sitting in a passenger seat falls asleep and the body leans toward a door, the head of the child with a low sitting height covers the front of the side airbag device housed in the side of the seat back. However, there is a problem that the side airbag cannot be effectively deployed. Therefore, a seat-shaped sensor is embedded between the pad of the seat back and the trim cover that covers the surface to detect the sitting posture and physique of the occupant sitting on the passenger seat, and the child rests on the door side. Has been already proposed by the present applicant (see Japanese Patent Application No. 10-3938).

Conventionally, a method of using an adhesive, a method of using a double-sided pressure-sensitive adhesive tape, or a method of performing double-sided pressure-sensitive adhesive processing has been adopted for attaching a sensor to a seatback pad.

[0004]

However, the method of attaching the sensor with an adhesive not only requires many steps such as adhesive application → sticking → pressing → drying but also increases the time required for the operation, There is a problem that the quality becomes unstable due to the variation in the application amount and the application position of the adhesive, and there is a concern that the use of a solvent-based adhesive may affect the working environment. When a double-sided pressure-sensitive adhesive tape or double-sided pressure-sensitive adhesive processing is employed, problems such as a decrease in adhesive strength when exposed to a high temperature and a decrease in durability against chemicals occur.

The present invention has been made in view of the above circumstances, and has as its object to enable a sensor of an occupant detection device to be easily and reliably fixed to a seat back.

[0006]

According to the first aspect of the present invention, a seat-like sensor is fixed to a seat back to detect a sitting posture and a physique of an occupant. An occupant detection device is proposed, wherein the sensor is welded to a seat back via a hot melt film.

[0007] According to the above configuration, the hot melt film can be melted and the sensor can be fixed to the seat back only by superposing the hot melt film and the sensor on the seat back and heat pressing. As a result, the sensor can be securely and firmly fixed to the seat back while significantly reducing the time required for the work, reducing the cost, and eliminating the adverse effect on the work environment.

According to the invention described in claim 2,
In addition to the configuration of the first aspect, an occupant detection device is proposed in which a hot melt film is temporarily welded to a sensor in advance.

According to the above construction, the hot melt film is preliminarily integrated into the sensor by temporary welding, so that the operation of superimposing the hot melt film and the sensor on the seat back is facilitated to prevent the occurrence of displacement, and Can be enhanced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 11 show a first embodiment of the present invention. FIG. 1 is a plan view of a passenger seat provided with a side airbag device, FIG. 2 is a perspective view of a passenger seat, and FIG. 5 is a view in the direction of arrows in FIG. 2, FIG. 4 is a sectional view taken along line 4-4 in FIG.
6 is an exploded perspective view of the passenger seat, FIG. 6 is an enlarged view of a part 6 in FIG. 3, FIG. 7 is an enlarged sectional view taken along the line 7-7 in FIG. 6, and FIG.
9 is an enlarged view of a part 9 in FIG. 3, FIG. 10 is a circuit diagram of an electric field output unit, and FIG.

As shown in FIG. 1, the side airbag device 3 for side collision stored in the side of the passenger seat 1 on the door 2 side of the seat back 12 at the time of side collision of the vehicle is seated on the passenger seat 1. The side airbag 4 is deployed between the occupant and the inner surface of the door 2. The side airbag device 3 does not operate when the occupant sitting on the passenger seat 1 is a child with a small sitting height and the child is leaning on the door 2 side. For this purpose, a state in which a child sitting on the passenger seat 1 is leaning against the door 2 is detected.
Sensors 14a, 14b, 14c (see FIGS. 2 to 5)
Is provided on the passenger seat 1.

As shown in FIGS. 2 to 5, the passenger seat 1
Is composed of a seat cushion 11, a seat back 12, and a headrest 13. The seat back 12 includes pads 15, 16, 17 made of an elastic material and trim covers 18, 19, 20 covering the front surface thereof. Between the inner surfaces of the trim covers 18 and 19 covering the front surface of the seat back 12 against which the back of the seated occupant hits, and the front surfaces of the pads 15 and 16, the seat-shaped first sensor 14 a and the second sensor 1 are arranged.
4b and the third sensor 14c are arranged.

The first sensor 14 a is bonded to the wadding 21 bonded to the front surface of the center pad 15 of the seat back 12 and to the rear surface of the trim cover 18 in order to improve the feeling when the occupant is seated. The seat back 12 is disposed at the center of the seat back 12 while being sandwiched between the wadding 22 and the wadding 22. Similarly, the second sensor 14b is positioned between the wadding 23 adhered to the front surface of the pad 15 at the center of the seat back 12 and the wadding 24 adhered to the rear surface of the trim cover 18 in the center of the seat back 12. Located at the top. The third sensor 14c is provided on the left side of the seat back 12 in a state where the third sensor 14c is sandwiched between the wadding 25 bonded to the front surface of the pad 16 on the left side of the seat back 12 and the wading 26 bonded to the rear surface of the trim cover 19. Be placed. One wadding 27 is adhered to the front surface of the pad 17 on the right side of the seat back 12 where no sensor is provided, and the front surface is covered by the trim cover 20.

As shown in FIG. 6, the first sensor 14a comprises a rectangular sheet-shaped sensor body 31, a harness 32 extending from the sensor body 31, and a connector 33 provided at the tip of the harness 32. Be composed. Four antenna electrodes 34a to 34d extending in the left-right direction are arranged in the upper and lower four stages on the sensor main body 31, and a large number of antenna electrodes 34a to 34d are provided so as to penetrate through the central portion and between the adjacent antenna electrodes 34a to 34d. Opening 36 of ...
Is formed.

As is apparent from FIGS. 8 and 9, the second sensor 14b and the third sensor 14c also include a sensor body 31, a harness 32, and a connector 33. The actual structure is the same as that of the first sensor 14a except for the dimensions of the first sensor 14a. Specifically, the sensor body 31 of the second sensor 14b is smaller than the sensor body 31 of the first sensor 14a, and the two antenna electrodes 34e to
34f are arranged in two upper and lower stages. The third sensor 14c
Of the sensor main body 31 is the smallest and extends in the vertical direction.
Only 34 g of antenna electrodes are provided.

Next, details of the sectional structure of the sensor main body 31 of the first to third sensors 14a to 14c will be described with reference to FIG. FIG. 7 shows a cross-sectional structure of the sensor body 31 of the first sensor 14a.
The cross-sectional structure of the sensor body 31 of b, 14c is also the same.

The antenna film 41 serving as a base of the sensor body 31 is made of a PET film (polyethylene terephthalate film) having a thickness of 50 μm to 100 μm. A first conductor layer 42 made of an Ag layer (silver layer) having a thickness of 5 μm to 11 μm is pattern-printed on the rear side of the antenna film 41, and a thickness of 7 μm to 13 μm is formed on the rear side of the first conductor layer 42. The second conductor layer 43 composed of the C layer (carbon layer) is pattern-printed. On the front side of the antenna film 41, a first protective layer 44 made of a flame-retardant synthetic resin resist paste layer having a thickness of 35 μm to 45 μm is pattern-printed, and the second conductor layer 4 is formed.
A second protective layer 45 made of a flame-retardant synthetic resin resist paste layer having a thickness of 7 μm to 17 μm is pattern-printed on the rear surface side of 3. Then, a thickness of 1 on the rear surface side of the second protective layer 45.
A hot melt film 46 of about 00 μm is partially thermally welded and temporarily fixed. The hot melt film 46 is melted by heating and generates an adhesive force when cooled and solidified.

A two-folded protective cloth 47 is adhered to the front and rear surfaces of one side edge of the sensor body 31.
7, the cords 48 of the harnesses 32 extending from the antenna electrodes 34a to 34d are fixed along the rear surface of the second protective layer 45. The first and second protective layers 4 are connected at the portions where the ends of the cords 48 are connected to the first and second conductive layers 42 and 43.
4 and 45 are cut out, and the two washers 49 and 49 fitted therein are fixed by caulking the eyelet 50.

The first sensor 14a having the above structure is fixed to the seat back 12 as follows. That is, after positioning the rear surface of the hot melt film 46 of the first sensor 14a in contact with the front surface of the wadding 21 previously bonded to the pad 15 of the seat back 12, the first sensor 14a
Pressing while applying heat of 200 ° C. or less from the front side of The hot melt film 46 melted by heating is solidified by cooling, and the first sensor 14a is firmly fixed to the wadding 21 by the adhesive force generated at that time.

In the same manner as the first sensor 14a, the second
The sensor 14b and the third sensor 14c
It is fixed via a hot melt film 46 to the front surfaces of the waddings 21 and 25 previously bonded to 16. And a trim cover 1 to which waddings 22, 24, and 26 are bonded in advance.
8, 19 and 20 cover the front surface of the seat back 12.

As described above, the first and second conductor layers 4 are formed on the PET antenna film 41 as a base.
Since the sensors 14a to 14c are formed by pattern printing of 2, 43, the manufacturing cost is extremely low and the durability is improved as compared with the conventional one in which the conductive cloth is adhered to the base cloth. It is possible to reduce the uncomfortable feeling of the occupant sitting on the passenger seat 1 by reducing the thickness of the passenger seat 1 to 14c. Further, since both surfaces of the sensors 14a to 14c are covered with the first and second protective layers 44 and 45, the first and second conductor layers 42 and 43 can be protected from external force and the corrosion resistance can be enhanced. .

Since the hot melt film 46 is used to fix the sensors 14a to 14c to the front surface of the seat back 12, the sensor 1 is located at a predetermined position on the seat back 12.
By simply positioning the 4a to 14c and heat pressing at a low temperature of 200 ° C. or less, the hot melt film 46 can be melted and the sensors 14a to 14c can be firmly fixed to the seat back 12 in a short time. In addition, there is no effect on the working environment due to the solvent that becomes a problem when using an adhesive,
There is no risk of quality degradation due to variations in the amount and position of application of the adhesive. Furthermore, when the double-sided pressure-sensitive adhesive tape or double-sided pressure-sensitive adhesive processing is adopted, the adhesive strength at high temperatures decreases,
Problems such as a decrease in durability against chemicals are also avoided.

Furthermore, by temporarily welding the hot melt film 46 to the sensors 14a to 14c in advance, the hot melt film 46 and the sensors 14a to 14c can be separately positioned at a predetermined position on the seat back 12 for positioning. In comparison, workability can be greatly improved.

FIG. 10 shows the first to third sensors 14a to 14c.
2 shows the principle of detecting the physique and posture of the occupant sitting on the passenger seat 1. In the electric field output section 61, one end of a current monitor resistor 64 for converting the output current I of the electric field generation section 63 into a voltage is connected to the other end of the electric field generation section 63 composed of a high-frequency oscillation circuit whose one end is grounded to the ground section 62. ,
The amplifier 65 is connected. The other end of the current monitor resistor 64 is connected to the amplifier 65, and the seven antenna electrodes 34a to 34g of the first to third sensors 14a to 14c.
Are sequentially connected at predetermined time intervals.

The occupant is not seated on the passenger seat 1,
Therefore, the antenna electrodes 34a to 34g connected to the other end of the current monitor resistor 64 (for example, the antenna electrode 34a)
When the human body 66, which is a dielectric, is not close to the antenna, the value of the output current I generated by the electric field emitted from the antenna electrode 34a depends on the distance between the antenna electrode 34a and the ground 62 and the dielectric constant of air (ε ≒). It becomes extremely small according to 1). As a result, the voltage generated across the current monitor resistor 64, that is, the output of the amplifier 65 also decreases. On the other hand, when the human body 66 having a larger dielectric constant (ε ≒ 80) than the air is seated on the passenger seat 1, as shown in FIG. 11, the distance between the antenna electrode 34a and the human body 66 and the distance to the antenna electrode 34a are increased. A large output current I according to the area of the human body 66 flows through the current monitor resistor 64, and a voltage generated across the current monitor resistor 64, that is, an amplifier 65
Output also increases.

Therefore, the first and second sensors 14a, 14b
By analyzing the output patterns of the amplifier 65 corresponding to the six antenna electrodes 34a to 34f in the occupant detection determination unit 67, the physique of the occupant sitting on the passenger seat 1 can be detected. In addition, based on the output of the amplifier 65 corresponding to one antenna electrode 34g of the third sensor 14c, it is possible to detect whether or not the occupant seated on the passenger seat 1 is leaning on the door 2. Thus,
The deployment of the side airbag device 3 can be reliably prohibited in a state where the child sitting on the passenger seat 1 falls asleep and the body is inclined toward the door 2.

Next, another embodiment of the first to third sensors 14a to 14c will be described with reference to FIG.

The sensor body 31 shown in FIG.
The first protective layer 44 is omitted from the first embodiment, and the antenna film 41, the first conductive layer 42, the second conductive layer 43, and the second protective layer are sequentially laminated from the front side to the rear side. 45 and a hot-melt film 46.

The sensor body 31 shown in FIG.
The first and second protective layers 44 and 45 are omitted from the first embodiment, and the antenna film 41, the first conductor layer 42, and the second conductor layer 4 are sequentially laminated from the front side to the rear side.
It has a four-layer structure consisting of 3 and a hot melt film 46.

The sensor body 31 shown in FIG.
The first and second protective layers 44 and 45 and the first conductive layer 42 are omitted from the first embodiment, and the antenna film 41 and the second conductive layer 43 are sequentially laminated from the front side to the rear side. And a hot-melt film 46.

As described above, by providing the antenna film 41 and at least one conductor layer, the first to fourth conductor layers are provided.
The third sensors 14a to 14c can exhibit their basic functions, and by adding the hot melt film 46 to the third sensors 14a to 14c, the fixing to the seat back 12 can be performed easily and reliably.

While the embodiments of the present invention have been described in detail above, various design changes can be made in the present invention without departing from the gist thereof.

For example, the materials and thicknesses of the antenna film 41, the first conductive layer 42, the second conductive layer 43, the first protective layer 44, the second protective layer 45, and the hot melt film 46 are the same as those of the embodiment. It is not limited, and can be appropriately changed.

[0035]

As described above, according to the first aspect of the present invention, the hot-melt film and the sensor are melted by simply superposing the hot-melt film and the sensor on the seat back and heat-pressing the sensor. Can be fixed. As a result, the sensor can be securely and firmly fixed to the seat back while significantly reducing the time required for the work, reducing the cost, and eliminating the adverse effect on the work environment.

According to the second aspect of the present invention,
Since the hot-melt film is preliminarily integrated with the sensor by temporary welding, the work of superimposing the hot-melt film and the sensor on the seat back can be facilitated, the occurrence of displacement can be prevented, and the workability can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a passenger seat provided with a side airbag device.

FIG. 2 is a perspective view of a passenger seat.

FIG. 3 is a view in the direction of arrows in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is an exploded perspective view of a passenger seat.

FIG. 6 is an enlarged view of part 6 of FIG.

FIG. 7 is an enlarged sectional view taken along line 7-7 of FIG. 6;

FIG. 8 is an enlarged view of part 8 of FIG. 3;

FIG. 9 is an enlarged view of part 9 of FIG.

FIG. 10 is a circuit diagram of an electric field output unit.

FIG. 11 is an explanatory diagram of an occupant physique detection method;

FIG. 12 is a diagram showing another embodiment of the sensor.

[Explanation of symbols]

 12 Seat back 14a First sensor (sensor) 14b Second sensor (sensor) 14c Third sensor (sensor) 46 Hot melt film

Continued on the front page (72) Inventor Nobuhiro Koshiro 1-4-1 Chuo, Wako-shi, Saitama Pref. Inside of Honda R & D Co., Ltd. (72) Inventor Naoto Ishii 1-4-1 Chuo, Wako-shi, Saitama Co., Ltd. Inside the Honda R & D Co., Ltd. (72) Inventor Koichi Uechi 1-4-1 Chuo, Wako-shi, Saitama F-term in the Honda R & D Co., Ltd. (Reference) 3B084 EC03 JA03 JA06 JC01 3B087 DE00 DE08 3D054 AA16 EE02 EE10 EE60 FF17

Claims (2)

[Claims] A seat-like sensor (14a-14) is provided on a seat back (12) to detect a sitting posture and a physique of an occupant.
An occupant detection device fixed to c), wherein the sensors (14a to 14c) are welded to the seat back (12) via a hot melt film (46). 2. The occupant detection device according to claim 1, wherein the hot melt film (46) is temporarily welded to the sensors (14a to 14c) in advance.