JP2001208623A - Seating sensor and detection device using the same - Google Patents

Abstract

(57) [Problem] To provide a seating sensor which is mounted on a seat or the like of an automobile and detects seating of an occupant in a seat and a detecting device using the same, the resistance value has less variation and stable resistance value characteristics are obtained. The aim is to provide what is obtained. SOLUTION: An upper insulating sheet 1 and a lower insulating sheet 3 include:
Plural low resistance layers 14 and 18 and high resistance layer 1 covering them
The movable contacts 16 and the fixed contacts 20 are formed by the 5, 19, and the plurality of movable contacts 16 and the fixed contacts 20 are sequentially contacted by the applied load, so that the contact points of the contacts increase, and the resistance value changes stepwise sequentially. By configuring the seating sensor, a variation in the resistance value is small, and a seating sensor with stable resistance value characteristics can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seating sensor which is mounted on a seat of an automobile or the like and detects a seating of an occupant in the seat, and a detecting device using the same.

[0002]

2. Description of the Related Art In recent years, as automobiles have become more sophisticated,
Various seating sensors are used to detect various weights of an occupant seated in a seat and control various functions such as controlling the operation of an airbag or displaying the seatbelt wearing. .

FIG. 1 shows such a conventional seating sensor.
This will be described with reference to FIGS.

FIG. 15 is a side sectional view of a conventional seating sensor. In FIG. 15, reference numeral 1 denotes a film-like upper insulating sheet made of polyethylene terephthalate, polyimide, or the like. The movable contact 2 is formed by printing with a resin in which conductive particles and insulating particles are dispersed.

[0005] Reference numeral 3 denotes a flexible film-like lower insulating sheet such as polyethylene terephthalate or polyimide disposed below the upper insulating sheet 1. The foil is etched or printed with a flexible resin such as polyester or epoxy in which silver or carbon is dispersed to form a pair of opposing conductor layers 4 and on the conductor layers 4 The resistor layer 5 is formed by printing with a resin in which conductive particles and insulating particles are dispersed, and a fixed contact 6 is formed.

Reference numeral 7 denotes an insulating spacer, which is provided by adhesives 7B and 7C applied to the upper and lower surfaces of the insulating film 7A.
The upper insulating sheet 1 and the lower insulating sheet 3 are bonded to each other, and an opening 7D is provided at a central portion.
Thus, a predetermined gap is secured between the movable contact 2 and the fixed contact 6 facing each other, and the seating sensor is configured.

As shown in the enlarged sectional view of FIG. 16, the resistor layer 5 of the movable contact 2 and the fixed contact 6 is made of resin 2A, 5A such as epoxy, phenol, polyester, etc. Conductive particles 2B, 5B of
With a particle diameter larger than the thickness of the resin 2A, 5A,
Insulating particles 2C and 5C that partially protrude from A and 5A are formed in a dispersed manner.

The seating sensor constructed as described above is mounted in the seat of the automobile, and when the occupant sits on the seat, FIG.
As shown in the side sectional view of FIG. 7, the weight of the occupant causes the upper insulating sheet 1 to bend, the movable contact 2 of the upper insulating sheet 1 comes into contact with the fixed contact 6 of the lower insulating sheet 3, and the pair of fixed contacts 6 The connection state is established via the movable contact 2.

Thereafter, when the load applied to the seating sensor by seating increases, as shown in the enlarged sectional view of FIG. 18, the contact area between the resins 5A, 2A in which the conductive particles 2B, 5B are dispersed increases. As shown by the characteristic c in the resistance characteristic diagram of FIG. 19, the resistance value decreases, and when a certain load is applied constantly, the contact area becomes constant, and the resistance value becomes a predetermined value compared with the initial contact. The following constant values are obtained.

The resistance value of the seat sensor is detected by an electronic circuit of the vehicle connected to the fixed contact 6, and it is determined whether the seat is seated or not and whether the weight of the seated occupant is equal to or more than a predetermined value. When seating is confirmed, the seatback is displayed or the airbag operation is controlled according to the weight of the occupant, for example, whether the child is an adult or the like.

[0011]

However, in the above-described conventional seating sensor, the movable contact 2 and the resistor layer 5 of the fixed contact 6 are brought into contact with each other, and the portions other than the insulating particles 2C and 5C protruding from the resins 2A and 5A are provided. Since the resistance value due to the change in the contact area is detected, the surface state of the movable contact 2 and the resistor layer 5, or the conductive particles 2B,
19B depending on the dispersion state of the insulating particles 5B and the insulating particles 2C and 5C.
As shown in the resistance characteristic diagram of FIG. 7, a characteristic d having a large resistance value as a whole with respect to the reference characteristic c and a characteristic e having a small resistance value with respect to the reference characteristic c.
When the load is applied repeatedly, the interface between the resin 2A, 5A and the insulating particles 2C, 5C protruding from the surface is peeled off to form a gap, thereby producing a resistance value characteristic. However, there was a problem that it was easy to become unstable compared with the initial stage.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a seating sensor capable of obtaining a stable resistance value characteristic with a small variation in resistance value and a detection device using the same. And

[0013]

According to the present invention, a plurality of movable contacts and fixed contacts are formed on an upper and lower insulating sheet by a plurality of low resistance layers and a high resistance layer covering the low resistance layers. The seating sensor is configured such that a plurality of movable contacts and fixed contacts sequentially contact with each other due to an applied load, the number of contact points of the contacts increases, and the resistance value sequentially changes stepwise.

[0014] Thereby, the variation of the resistance value is small,
A seating sensor having a stable resistance characteristic can be obtained.

[0015]

DETAILED DESCRIPTION OF THE INVENTION According to the first aspect of the present invention, a flexible film-shaped upper insulating sheet and a flexible film-shaped upper insulating sheet disposed below the upper insulating sheet are provided. The lower insulating sheet, a plurality of low-resistance layers formed on the lower and upper surfaces of the upper and lower insulating sheets, and a resin formed by dispersing conductive particles so as to cover the surfaces of the low-resistance layers and the upper and lower insulating sheets. A movable contact and a fixed contact made of a high resistance layer, and a seating sensor made of an insulating spacer formed between upper and lower insulating sheets so that the movable contact and the fixed contact face each other with a predetermined gap. A plurality of movable contacts and fixed contacts are formed by a plurality of low-resistance layers and a high-resistance layer covering the same, and the movable contacts and the fixed contacts, in which only conductive particles are dispersed, are sequentially contacted and contacted by an applied load. Increases the contact points, with the resistance value changes sequentially and gradually, less variations in resistance value, the effect that it is possible to obtain stable seating sensor resistance value characteristics.

According to a second aspect of the present invention, there is provided a flexible film-shaped upper insulating sheet, a flexible film-shaped lower insulating sheet disposed below the upper insulating sheet, Formed on the lower and upper surfaces of the insulating sheet, a high-resistance layer formed by printing with a resin in which conductive particles are dispersed, and a plurality of layers formed by printing on the high-resistance layer with a resin in which conductive particles are dispersed. A movable contact and a fixed contact made of a low-resistance layer, and a seating sensor made of an insulating spacer formed between upper and lower insulating sheets so that the movable contact and the fixed contact face each other with a predetermined gap. A movable contact and a fixed contact are formed by providing a plurality of low-resistance layers on the high-resistance layer. Portion increases, the resistance value changes sequentially and gradually, the variation of the resistance value is small, an effect that can be obtained seating sensors smaller stable resistance value characteristics.

According to a third aspect of the present invention, in the first or second aspect, one of the movable contact and the fixed contact is opposed to the other by at least one of the low-resistance layer and the high-resistance layer. Because the movable contact or the fixed contact is formed flat in the predetermined range, there is a slight shift when the upper insulating sheet and the lower insulating sheet are bonded together. Even when the upper and lower insulating sheets are stuck together in a state where the seating sensor is stuck, there is an effect that a variation in the resistance value is small and a seating sensor that can obtain a stable resistance value characteristic can be obtained.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the upper and lower insulating sheets are provided with extraction electrodes connected to the movable contact and the fixed contact. A fixed resistor layer whose one end is connected to the electrode is formed, so that a seating sensor integrally provided with a comparison resistor and a reference resistor of a detection circuit can be obtained, and the fixed low-resistance layer is formed as a movable contact or a fixed contact. By simultaneously printing with the same material as that of the high-resistance layer, the temperature characteristics and humidity characteristics become the same, so that a seating sensor in which the variation in the resistance value of the movable contact and the fixed contact due to temperature and humidity is corrected is obtained. It has the effect of being able to.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a portion of the high-resistance layer of the movable contact or the fixed contact other than an overlapping portion with the low-resistance layer is provided. A predetermined hole or notch is provided at a location, and the range of change in the overall resistance value can be increased as compared with the case where a high-resistance layer is formed on the entire surface, and the size of the hole or notch can be increased. By adjusting the position of the sheath, the resistance value of the movable contact and the fixed contact can be arbitrarily adjusted.

According to a sixth aspect of the present invention, in the first aspect, a plurality of movable contacts and fixed contacts are formed on the upper and lower insulating sheets. When several seating sensors need to be used, it is easy and inexpensive to assemble into a device by forming a plurality of layers on the upper and lower sheets and using a seating sensor in which a plurality of contact portions are connected. It has the effect that it can be.

According to a seventh aspect of the present invention, there is provided the seat sensor according to any one of the first to sixth aspects, and a detection circuit connected to the sensor. Is a detection device that detects the resistance value when the load is applied, determines the applied load based on the difference in the resistance value, and performs different control depending on the difference in the load. A detection device capable of controlling various functions, such as controlling the operation of an airbag or displaying seatbelt wearing, for example, by detecting the weight of the seat as a difference in the resistance value of the seating sensor. , Which can be realized at low cost.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS.

The same components as those described in the section of the related art are denoted by the same reference numerals, and detailed description thereof will be omitted.

(Embodiment 1) FIG. 1 is a side sectional view of a seated sensor according to a first embodiment of the present invention, and FIG. 2 is a plan sectional view of the lower insulating sheet. In FIG. A flexible film-shaped upper insulating sheet such as polyethylene terephthalate, polyimide, or polynaphthalene terephthalate, and a lower surface of the upper insulating sheet 1 is provided with a flexible material such as polyester or epoxy in which conductive particles such as silver or carbon are dispersed. A plurality of ring-shaped low-resistance layers 14 are printed and formed concentrically with the extraction electrode 13 by a resin having a property, and the low-resistance layer 14 and the surface of the upper insulating sheet 1 are covered.
The movable contact 16 is formed by printing and forming the high-resistance layer 15 with a flexible resin such as polyester or epoxy in which conductive particles such as carbon are dispersed.

Reference numeral 3 denotes a flexible film-shaped lower insulating sheet such as polyethylene terephthalate, polyimide, or polynaphthalene terephthalate disposed below the upper insulating sheet 1; A plurality of low-resistance layers 18 concentric with the extraction electrode 17 and formed in a ring shape, and a high-resistance layer 19 is formed by printing so as to cover the low-resistance layer 18 and the surface of the lower insulating sheet 3. Are formed.

Reference numeral 7 denotes an insulating spacer, and the upper insulating sheet 1 and the lower insulating sheet 3 are bonded together by adhesives 7B and 7C of a resin such as polyester or acrylic applied to the upper and lower surfaces of the insulating film 7A. An opening 7D is provided in the center, and a predetermined gap is secured between the movable contact 16 and the fixed contact 20 facing each other by the opening 7D, thereby forming a seating sensor.

When the seating sensor constructed as described above is mounted in the seat of an automobile and an occupant sits on the seat, the weight of the occupant causes the upper insulating sheet 1 to bend and the movable contact 16 of the upper insulating sheet 1 to move downward. The fixed contact 20 of the insulating sheet 3 is contacted. At this time, for example, when the occupant is a child and the load is small, the upper insulating sheet 1 is less bent as shown in the side sectional view of FIG. Since only the central movable contact 16 and the central fixed contact 20 are in contact with each other, the resistance value is large.

When the occupant is an adult and the load is large, as shown in FIG. 3B, in addition to the center, the movable contact 16 and the fixed contact 20 at two places on the outer periphery also come into contact with each other. The number of locations increases and the contact area increases, resulting in a small resistance value.

FIG. 4 is a detection circuit diagram of the seating sensor. In FIG. 4, reference numeral 21 denotes a seating sensor having the above-described structure, 22 denotes a comparison resistor, 23 denotes a reference resistor, and 23 denotes a reference resistor.
Is connected to the extraction electrode 13, and the reference resistor 23 is connected to the extraction electrode 1.
3 and the extraction electrode 17 are connected in parallel.

In the above configuration, when a constant voltage is applied to the input terminal 24, the seat sensor 21 is operated, and the voltage output from the output terminal 25 is converted into a resistance value. As the number of contacts increases and the number of contact points increases as the movable contact 16 and the fixed contact 20 sequentially contact, as shown in the resistance characteristic diagram of FIG.
The resistance value gradually decreases gradually.

As shown in the enlarged sectional view of FIG. 6 (a), the movable contact 16 and the fixed contact 20 actually have fine irregularities on the surface. In this case, as shown in FIG. 6B, the uneven surfaces of the high-resistance layer 15 and the high-resistance layer 19 come into contact with each other.

Normally, the resistance of the high-resistance layers 15 and 19 having a large resistance is the resistance of the seating sensor. In the case of this embodiment, however, the high-resistance layer 15 and the high-resistance layer Since the low resistance layer 14 and the low resistance layer 18 having a small resistance value are formed on the lower surface of 19, the vertical high resistance layers 15 and 19 penetrating from the surface to the low resistance layers 14 and 18 are formed. The sum of the resistance value and the resistance values of the low-resistance layers 14 and 18 having a small resistance value is the resistance value of the seating sensor.

As described above, according to the present embodiment, the plurality of low-resistance layers 14 and 18 and the high-resistance layers 15 and 1 covering the same are covered.
9, the movable contact 16 and the fixed contact 20 are formed, and the movable contact 16 and the fixed contact 20 in which only the conductive particles are dispersed are sequentially contacted by the applied load, so that the number of contact points of the contact increases, and the resistance value is gradually increased. Therefore, a variation in the resistance value is small, and a seating sensor with stable resistance value characteristics can be obtained.

In the above description, the extraction electrodes 13, 1
7 and the low-resistance layers 14 and 18 have been described as being simultaneously formed by printing with a resin in which conductive particles are dispersed. However, these may be separately formed by printing using materials having different resistance values, or one or the other. By forming both by etching a copper foil or the like attached to the upper insulating sheet 1 or the lower insulating sheet 3, the resistance value can be further reduced and stabilized.

(Embodiment 2) FIG. 7 is a side sectional view of a seating sensor according to a second embodiment of the present invention. In FIG. 7, the seating sensor has flexibility such as polyethylene terephthalate, polyimide, and polynaphthalene terephthalate. On the lower surface of the film-shaped upper insulating sheet 1, a high-resistance layer 28 is formed by printing with a flexible resin such as polyester or epoxy in which conductive particles such as carbon are dispersed, and on the high-resistance layer 28. A plurality of concentric and ring-shaped low-resistance layers 29 are formed by printing with a flexible resin such as polyester or epoxy in which conductive particles such as silver or carbon are dispersed, and the movable contact 30 is formed. I have.

Similarly, on the upper surface of the lower insulating sheet 3, a plurality of concentric ring-shaped low-resistance layers 32 are printed on the high-resistance layer 31 to form fixed contacts 33, and the insulating spacers are formed. 7, a predetermined gap is secured between the movable contact 30 and the fixed contact 33, and a seating sensor is configured.

In the above configuration, when a load is applied to the seating sensor, the upper insulating sheet 1 bends, and the movable contact 30 of the upper insulating sheet 1 contacts the fixed contact 33 of the lower insulating sheet 3,
When the load is small, the movable contact 30 and the fixed contact 3
Since only a part of the contacts 3 makes contact, the resistance becomes large. When the load is large, the plurality of movable contacts 30 and the plurality of fixed contacts 33 come into contact with each other, and the number of contact points of the contacts increases. This is the same as in the first embodiment, but the contact between the movable contact 30 and the fixed contact 33 contacts the low-resistance layer 29 having a small resistance formed on the high-resistance layers 28 and 31. Since this is performed by the resistor layer 32, FIG.
As shown in the resistance value characteristic diagram of FIG. 5, the resistance value is small, and the stepwise change becomes even more linear and clear.

As described above, according to the present embodiment, the movable contact 30 and the fixed contact 33 are formed by providing the plurality of low-resistance layers 29 and 32 on the high-resistance layers 28 and 31 and apply a load. As a result, the low-resistance body layer 29 and the low-resistance body layer 32 having a small resistance value sequentially come into contact with each other, the number of contact points of the contacts increases, and the resistance value changes in a stepwise manner. It is possible to obtain a seating sensor having a small value variation and a stable resistance value characteristic.

In the first embodiment, the low-resistance layer 14,
In the present embodiment, a description has been given of a configuration in which the low-resistance layers 29 and 32 are each formed as a concentric ring-shaped low-resistance layer in the present embodiment, but as shown in a plan sectional view of FIG. The low-resistance layer 35 is formed radially, and the high-resistance layer 36 is formed above or below the low-resistance layer 35, or the low-resistance layer is formed in a smaller dot shape as shown in FIG.
As shown in the resistance value characteristic diagram, the width of the change in the resistance value with respect to the load can be increased, and the stepwise change can be made even finer. Of the body weight can be set, and the so-called resolution as a seating sensor can be finely set.

Further, in the above description, the configuration in which an insulating resin film such as polyethylene terephthalate, polyimide, or polynaphthalene terephthalate is used for the upper insulating sheet 1 and the lower insulating sheet 3 has been described. It is needless to say that the present invention can be implemented as long as the film has flexibility in the form of a film. For example, when a silicon-based rubber sheet having a heat-resistant temperature exceeding 90 ° C. is used for the upper insulating sheet 1, Compared with polyethylene terephthalate or polynaphthalene terephthalate, the deformation of the upper insulating sheet 1 that is likely to occur when a load is applied at a high temperature can be reduced.

Furthermore, in order to secure a gap between the movable contact and the fixed contact opposed to each other, the configuration is described in which the insulating spacers 7 having the adhesives 7B and 7C applied on the upper and lower surfaces are used. Or on the upper surface of the lower insulating sheet 3,
The present invention is also applicable to a configuration in which an insulating spacer is formed by printing with a flexible resin such as epoxy, phenol, or polyester to thereby secure a gap between the movable contact and the fixed contact.

(Embodiment 3) FIG. 11 is a side sectional view of a seating sensor according to a third embodiment of the present invention. In FIG. 11, a film-shaped upper insulating sheet 1 having flexibility is shown.
A plurality of concentric ring-shaped low-resistance layers 14 are printed and formed on the lower surface of the substrate by a flexible resin in which conductive particles such as silver and carbon are dispersed, and the low-resistance layers 14 and the upper insulating sheet 1 are formed. The high-resistance layer 15 is made of a flexible resin in which conductive particles such as carbon are dispersed so as to cover the surface.
Is formed by printing to form the movable contact 16 as in the case of the first embodiment.

As in the first embodiment, a predetermined gap is secured between the upper insulating sheet 1 and the lower insulating sheet 3 with the insulating spacer 7 interposed therebetween. The extraction electrode 17 and the low-resistance layer 38 are integrally formed by printing on the upper surface of a flexible resin such as polyester or epoxy in which conductive particles such as silver or carbon are dispersed. A high-resistance layer 39, which is formed by printing a flexible resin such as polyester or epoxy in which particles are dispersed, covers the entire surface of the low-resistance body 38 in a predetermined range facing the movable contact 16, and the fixed contact 4
0 is formed to constitute a seating sensor.

In the above configuration, when a load is applied to the seating sensor, the upper insulating sheet 1 bends, and the movable contact 16 of the upper insulating sheet 1 comes into contact with the fixed contact 40 of the lower insulating sheet 3. Since the movable contact 40 is formed flat in a predetermined range, the movable contact 1 protrudes concentrically in a ring shape.
Numeral 6 is configured to reliably contact the fixed contact 40 even if it is slightly displaced.

As described above, according to the present embodiment, the low-resistance layer 38 and the high-resistance layer 39 are formed on the entire surface of the predetermined range facing the movable contact 16 so that the fixed contact is flat in the predetermined range. Since the upper insulating sheet 1 and the lower insulating sheet 3 are bonded together via the insulating spacer 7 because the 40 is formed,
Even if the upper and lower insulating sheets 1 and 3 are stuck to each other in a slightly displaced state, a variation in the resistance value is small and a seating sensor with stable resistance value characteristics can be obtained.

In the above description, a configuration in which the fixed contact 40 is flat within a predetermined range has been described.
Conversely, the present invention can be implemented even if the fixed contact is formed of a plurality of low-resistance layers and a high-resistance layer covering the low-resistance layer, and the working contact is flat in a predetermined range.

Although the low-resistance body layer 38 and the high-resistance body layer 39 have been described as being formed by printing on top of each other, depending on the environment in which the seating sensor is used, only one of them may be printed or formed. Alternatively, the present invention can be implemented by forming a low-resistance layer by etching a copper foil or the like plated with gold, silver, or the like.

Further, as shown in the plan sectional view of FIG. 12, the extraction electrodes 13, 1 connected to the movable contact and the fixed contact.
7, fixed resistor layers 41 and 42 having one end connected to the extraction electrode 17 and the other end connected to the extraction electrodes 41A and 42A are formed by printing with a resin such as polyester or epoxy in which conductive particles such as carbon are dispersed. By doing so, FIG.
The comparison resistor 22 and the reference resistor 23 on the detection circuit side shown in FIG.
An integrated seating sensor can be obtained, and by simultaneously forming the fixed resistor layers 41 and 42 with the same material as the high-resistance layer of the movable contact and the fixed contact, the temperature characteristics and humidity characteristics are the same. Therefore, it is possible to obtain a seating sensor in which variations in the resistance values of the movable contact and the fixed contact due to temperature and humidity are corrected.

By providing a notch or a hole 43A in a predetermined portion of the high resistance layer 43 of the movable contact or the fixed contact 44 other than the overlapping portion with the low resistance layer 18, for example, the low resistance layer 18A Is connected to the extraction electrode 17 by the plurality of conductive portions 43B,
8, the width of the change in the overall resistance value can be increased and the hole 4
By adjusting the size and position of 3A, the resistance value of the movable contact and the fixed contact can be arbitrarily adjusted.

(Embodiment 4) FIG. 13 is a block diagram of a detection device according to a fourth embodiment of the present invention. In FIG. 13, reference numeral 45 denotes the seating sensor described in Embodiments 1-3. A seating sensor 45 is mounted on the seating surface of the seat 46 and the inside of the backrest, and a detecting circuit 47 is connected to the seating sensor 45 to form a detecting device.

In the above configuration, when an occupant sits on the seat 46, this load is applied to the seating sensor 45,
As described in the first to third embodiments, when the resistance value of the seating sensor 45 changes, after that, when the seating is completed and a certain load is applied to the seating sensor 45, the resistance becomes constant below a predetermined value. The resulting resistance value is output from the seating sensor 45 to the detection circuit 47.

The resistance value is detected by the detection circuit 47, and the load applied to the seat sensor 45, that is, the presence or absence of the seat, and the weight of the seated occupant are determined based on whether the resistance value is equal to or less than a predetermined value. It is determined whether or not the weight of the occupant is equal to or greater than a predetermined value by outputting the signal to the electronic circuit of the automobile, thereby displaying that the seat belt is worn when seating is confirmed, or determining whether the weight of the occupant is equal to or greater than the predetermined value. It is configured to control the airbag operation.

As described above, according to the present embodiment, the detection circuit 47 connected to the seat sensor 45
Since the detection device is configured to detect a resistance value when a predetermined load is applied to the device, determine the applied load based on the difference in the resistance value, and perform different control depending on the difference in the load, The presence / absence of seating and the weight of the seated occupant are detected as a difference in the resistance value of the seating sensor 45, thereby controlling various functions such as controlling the operation of an airbag and displaying the wearing of a seat belt. An inexpensive detection device can be realized.

In the first to third embodiments, the seating sensor has been described as a single seating sensor in which a pair of fixed contacts and a movable contact are opposed to each other with a predetermined gap. When it is necessary to use such a single seating sensor on the seat, and connecting each of them to the detection circuit requires a lot of assembly time, as shown in the plan view of FIG. A plurality of fixed contacts and movable contacts are formed on an insulating sheet, and the seating sensor has a configuration in which a plurality of contact portions 48 are integrally connected. By using this, it is easy and inexpensive to assemble the device. be able to.

[0055]

As described above, according to the present invention, a seating sensor having a small variation in resistance and a stable resistance characteristic.
And a detection device using the same can be obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a seating sensor according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of the lower insulating sheet.

FIG. 3 is a side sectional view at the time of the same operation.

FIG. 4 is a diagram of the detection circuit.

FIG. 5 is a characteristic diagram of the resistance value.

FIG. 6 is an enlarged sectional view of the same.

FIG. 7 is a side sectional view of a seating sensor according to a second embodiment of the present invention.

FIG. 8 is a resistance characteristic diagram of the same.

FIG. 9 is a cross-sectional plan view of the insulating sheet.

FIG. 10 is a resistance characteristic diagram of the same.

FIG. 11 is a side sectional view of a seating sensor according to a third embodiment of the present invention.

FIG. 12 is a cross-sectional plan view of the insulating sheet.

FIG. 13 is a block diagram of a detection device according to a fourth embodiment of the present invention.

FIG. 14 is a plan view of the same.

FIG. 15 is a side sectional view of a conventional seat sensor.

FIG. 16 is an enlarged sectional view of the same.

FIG. 17 is a side sectional view showing the same operation.

FIG. 18 is an enlarged sectional view of the same.

FIG. 19 is a characteristic diagram of the resistance value.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Upper insulating sheet 3 Lower insulating sheet 7 Insulating spacer 7A Insulating film 7B, 7C Adhesive 7D Opening hole 13, 17, 41A, 42A Extraction electrode 14, 18, 18A, 29, 32, 35, 38 Low-resistance body layer 15, 19, 28, 31, 36, 39, 43 High-resistance layer 16, 30 Movable contact 20, 33, 40, 44 Fixed contact 21, 45 Seating sensor 22 Comparative resistance 23 Reference resistance 24 Input terminal 25 Output terminal 41, 42 Fixed Resistor layer 43A Hole 43B Conductive part 46 Seat seat 47 Detection circuit 48 Contact part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takao Matsui 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 2F051 AA01 AB07 AC01 BA07 3B087 DE08 3D018 QA01 3D054 EE09 EE10 EE31

Claims (7)

[Claims] 1. A flexible film-shaped upper insulating sheet, a flexible film-shaped lower insulating sheet disposed below the upper insulating sheet, and a lower surface and an upper surface of the upper and lower insulating sheets. Formed, a plurality of low-resistance layers, and a movable contact and a fixed contact consisting of a high-resistance layer printed by a resin in which conductive particles are dispersed so as to cover the surface of the low-resistance layer and the upper and lower insulating sheets, A seating sensor comprising an insulating spacer formed between upper and lower insulating sheets so that the movable contact and the fixed contact face each other with a predetermined gap. 2. A flexible film-shaped upper insulating sheet, a flexible film-shaped lower insulating sheet disposed below the upper insulating sheet, and a lower surface and an upper surface of the upper and lower insulating sheets. A movable high-resistance layer formed by printing with a resin in which conductive particles are dispersed, and a plurality of low-resistance layers formed by printing on the high-resistance layer with a resin in which conductive particles are dispersed. A seating sensor comprising a contact and a fixed contact, and an insulating spacer formed between upper and lower insulating sheets such that the movable contact and the fixed contact face each other with a predetermined gap. 3. The seat according to claim 1, wherein at least one of the movable contact and the fixed contact is formed on at least one of the low-resistance layer and the high-resistance layer over an entire surface of a predetermined area facing the other. Sensor. 4. An upper and lower insulating sheet provided with an extraction electrode connected to a movable contact and a fixed contact, and a fixed resistor layer having one end connected to the extraction electrode.
3. The seating sensor according to any one of 3. 5. A high-resistance layer of a movable contact or a fixed contact, wherein a predetermined hole or notch is provided in a portion other than an overlapping portion with a low-resistance layer. Seating sensor. 6. The seating sensor according to claim 1, wherein a plurality of movable contacts and fixed contacts are formed on the upper and lower insulating sheets. 7. A seating sensor according to claim 1 and a detection circuit connected to the seating sensor, wherein the detection circuit is configured to provide a resistance when a predetermined load is applied to the seating sensor. A detection device that detects a value, determines a load applied based on a difference in the resistance value, and performs different control depending on the difference in the load.