JP7239850B2 - sheet - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat, and more particularly to a seat having a function of measuring heartbeats.

In recent years, in order to quickly notify the occurrence of an abnormality in the physical condition of a vehicle occupant, there has been proposed a configuration for determining an abnormal physical condition by detecting various parameters indicating the condition of the occupant.

For example, in Patent Document 1, a heartbeat sensor (referred to as an electrocardiographic sensor electrode in the same document) arranged on a seat back and a ground electrode arranged on a seat cushion A vehicle seat provided with an electrocardiographic sensor is disclosed in the literature.
The heartbeat sensor detects a potential signal from the heart of the seated person as a parameter indicating the state of the occupant, and monitors the state of health of the occupant.

Further, in Patent Document 2, plane electrode groups are provided at positions where the seated person's back, waist, buttocks, and thighs are in contact, and a biological signal is detected from a difference signal of potential signals detected from each plane electrode group. An invention related to a biological signal acquisition device is disclosed.
More specifically, this potential signal is a potential signal emitted from the vicinity of the heart or lungs. By using the acquisition method, signal noise is suppressed, and biological signals such as the heartbeat and respiration of the seated person are collected.

JP 2009-106673 A Japanese Patent Application Laid-Open No. 2007-301175

By the way, when a vehicle is driven, the contact area between the seat and the seat of the seated occupant is not constant due to shaking and centrifugal force acting when the vehicle travels around a curve.
Also, when the physique of the seated person is different, the point at which the biosignal can be preferably detected is different.
Therefore, it has been difficult to stably detect a biological signal from a seated person in a vehicle seat.
In particular, this problem is conspicuous when a biosignal is detected by a sensor provided on the seat back. The reason for this is that the contact portion of the seat back with the occupant changes as the occupant swings back and forth and to the left and right due to the shaking of the vehicle, and also varies greatly depending on the physique of the occupant.
In the heartbeat sensor described in Patent Document 1, the heartbeat sensor electrodes are provided only on the seat back, so it is difficult to suitably detect the electrocardiographic signal for the above reasons.

On the other hand, in the plane electrode group described in Patent Document 2, any one of the plane electrodes is used as a ground electrode, and potential signals are acquired from the other two, and the potential signals are related to heartbeat and respiration. Therefore, it is possible to obtain a potential signal more stably than in Patent Document 1.
However, since the seated person's own weight is greatly applied to the plane electrodes provided on the seat cushion, the conducting wires arranged on the plane electrodes may break.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet capable of suppressing disconnection of conductors provided in electrodes constituting a heartbeat sensor and capable of suitably detecting an electrocardiographic signal. and

According to the seat according to the present invention, the heart rate sensor having an electrode unit for detecting a potential signal corresponding to the cardiac potential of the person sitting on the seat, and the potential signal obtained from the heart rate sensor can be used to detect the consciousness of the person sitting on the seat. and an arithmetic processing unit that performs an arithmetic operation for identifying a level, wherein the electrode section is composed of a conductive sheet and a plurality of conductors, and the plurality of conductors extend around the conductor sheet. and a plurality of other portions that intersect with the one portion, and the electrode portion is formed in a rectangular sheet shape elongated in one direction, and the In the conductive sheet, cut portions are formed in pairs in the short direction on the side of the periphery of the electrode portion that extends in the long direction, and the plurality of other portions of the conductor wire are connected to the electrode portion . from one of the four corners to the opposing cut portion, extending toward the inside of the portion disposed along the periphery of the conductive sheet and disposed along the periphery of the conductive sheet The seat intersects at a plurality of positions inside the part, the seat includes a seat back that serves as a backrest for the seated person, the seat back further includes a pad and a skin material covering the pad, The pad of the seat back has a narrow portion narrowed in the seat width direction and a wide portion wider than the narrow portion, and the electrode portion is elongated in the seat extending direction. The conductive sheet has a narrow portion of the conductive sheet whose width is narrowed in the sheet width direction, and the electrode portion extends over the narrow portion and the wide portion of the pad. and the narrow portion of the conductive sheet is arranged in the narrow portion of the pad.
Since the conducting wire is wired from the corner of the electrode portion, which is less susceptible to the bending load, the occurrence of disconnection can be suppressed.

Further, the surface of the pad is divided into a plurality of areas by boundary lines, and the electrode section of the heart rate sensor is arranged within one of the plurality of areas without crossing over the boundary lines. preferably .

Further, it is preferable that a seat cushion on which the seated person sits and a respiration sensor are provided , the heartbeat sensor is provided on the seat back, and the respiration sensor is provided on the seat cushion.

In addition, the surface of the pad that constitutes the seat cushion is divided into a plurality of areas by boundary lines, and the respiratory sensor is positioned within one of the plurality of areas without crossing the boundary lines. is preferably placed in

Further , it is preferable that the conductive sheet has a cut portion other than the cut portion formed in an intermediate portion on the short side of the electrode portion.
According to the above configuration, since the cut portion is formed, it is possible to suppress the occurrence of wrinkles, and it is possible to lengthen the short side of the electrode portion. It is possible to suppress the occurrence of disconnection by suppressing the influence of

Advantageous Effects of Invention According to the present invention, it is possible to prevent a plurality of conducting wires from being disconnected together, and to suitably detect an electrocardiographic signal.
Moreover, according to the present invention, it is possible to suppress the occurrence of disconnection of the conductors forming the electrode portion of the heart rate sensor.
Moreover, according to the present invention, it is possible to suppress the occurrence of disconnection at the intersection of the conductors.
Moreover, according to the present invention, it is possible to suppress disconnection of the conductive wire due to a bending load applied in the short direction of the electrode portion.
Moreover, according to the present invention, it is possible to suppress the occurrence of disconnection of the electrode portion while making it possible to lengthen the short side of the electrode portion.
Further, according to the present invention, wire breakage can be suppressed by wiring the conducting wires from the corners of the electrode portions that are less susceptible to the bending load.

1 is a perspective view showing the overall configuration of a vehicle seat according to this embodiment; FIG. (A) is a schematic front view showing a seat back provided with an electrode section that constitutes a heartbeat sensor, and (B) is a schematic plan view showing a seat cushion provided with a respiration sensor. It is an enlarged view which shows an electrode part. It is a figure which shows the IV-IV cross section of FIG. 3, and is one part sectional drawing of an electrode part. (A) is a conceptual diagram showing a basic pattern of conductors, and (B) is a conceptual diagram showing a connection pattern in which the basic patterns are combined.

TECHNICAL FIELD The present invention relates to a seat, and more particularly to a seat having a function of stably measuring heartbeats.
The embodiments described below are merely examples for facilitating understanding of the present invention, and do not limit the present invention. That is, the shape, size, arrangement, etc. of the members described below can be changed and improved without departing from the scope of the present invention, and the present invention naturally includes equivalents thereof.
In the following description, the traveling direction of the vehicle is defined as the forward direction, the reverse direction is defined as the rearward direction, and the height direction of the vehicle is defined as the vertical direction.
A vehicle seat S according to an embodiment of the present invention will be specifically described below with reference to the accompanying drawings.

First, the overall configuration of the vehicle seat S will be described with reference to FIGS. 1 and 2. FIG.
Here, FIG. 1 is a perspective view showing the overall configuration of the vehicle seat S according to this embodiment, and FIG. FIG. 2B is a schematic plan view showing a seat cushion S2 provided with a respiratory sensor 9. FIG.
In FIGS. 1 and 2, some of the components (for example, the lead wire 11d) are omitted in order to make the arrangement positions of the respiratory sensor 9 and the heart rate sensor 10 easier to understand.
As shown in FIG. 1, the vehicle seat S includes a seat cushion S2 on which a seated person sits, and a seat which is a portion rotatably attached to the rear portion of the seat cushion S2 and is a portion that contacts the backrest of the seated person. A back S1 and an awakening maintenance device U for maintaining awakening of a seated person are provided.

The seat back S1 includes a cushion pad S1a made of urethane and a skin material S1b provided so as to cover the cushion pad S1a.
Further, as shown in FIGS. 1 and 2A, the seat back S1 is provided with the electrode portion 11 and the conductive cloth 26 at a position facing the waist of the seated person.

The seat cushion S2 includes a urethane cushion pad S2a and a covering material S2b.
Further, as shown in FIGS. 1 and 2B, the seat cushion S2 is provided with a breathing sensor 9 at a position facing the buttocks of the seated person.

1 and 2 show a configuration in which the respiratory sensor 9, the electrode section 11, and the conductive cloth 26 are arranged on the seating surface. On the other hand, these may be arranged between the cushion pad S1a and the skin material S1b or between the cushion pad S2a and the skin material S2b, thereby improving the appearance.
The respiratory sensor 9, heart rate sensor 10, detection device 21, arithmetic processing device 22, and vibrating device 23 constitute the wakefulness maintenance device U, and the details thereof will be described below.

<Regarding the configuration of the wakefulness maintenance device>
The wakefulness maintenance device U will be described with reference to FIGS. 3 to 5 in addition to FIGS. 1 and 2. FIG.
Here, FIG. 3 is an enlarged view showing the electrode portion 11, FIG. 4 is a sectional view taken along line IV-IV of FIG. FIG. 5B is a conceptual diagram showing a basic shape pattern 18, and FIG. 5B is a conceptual diagram showing a connecting pattern 19 in which the rectangular portions 19a and 19b are combined.

The arousal maintenance device U is a device for mainly maintaining the arousal of the seated person who is the driver. consists of

The respiration sensor 9 is a known pressure sensor, and detects a pressure signal, which is a signal indicating the level of consciousness that fluctuates with the breathing of the seated person. For example, the respiratory sensor 9 may be a piezo sensor pressure sensor, a semiconductor piezoresistive pressure sensor, a strain gauge pressure sensor, a capacitance pressure sensor, a silicon resonant pressure sensor, or the like.
The breathing sensor 9 in the example of the present embodiment has a substantially M shape and is disposed on the seat cushion S2 so that the open side faces rearward.

The heartbeat sensor 10 detects an electrocardiographic signal, which is an action potential signal generated in association with the heartbeat of the seated person and indicates the level of consciousness, and is provided in pairs in the seat width direction. consists of
Between the pair of electrode portions 11 in the seat width direction, a strip-shaped conductive cloth 26 narrower than the electrode portions 11 and longer in the height direction is arranged.
The conductive cloth 26 is a conductive cloth partially containing a metal material, is connected to the body of the vehicle body, functions as a ground, and serves as a reference potential when removing an offset signal included in the signal of the electrode portion 11. It acquires the electric potential.

(About the electrode part)
As shown in FIG. 3, the electrode portion 11 is formed in a rectangular sheet shape that is elongated in the vertical direction, has an area of about 100 cm ² and has a capacitance of about 3000 pF.
The electrode portion 11 is mainly composed of a conductive sheet 11a, and is attached onto the cushion pad S1a of the seat back S1 with a double-sided tape 11ad attached to the back surface of the conductive sheet 11a.

As shown in FIG. 4, the conductive sheet 11a includes a first resin film 11ac, a conductor wire 11d attached on the first resin film 11ac, and a second resin film 11a attached to the first resin film 11ac so as to sandwich the conductor wire 11d. It has a laminated structure composed of a resin film 11ab and ink 11aa applied to the second resin film 11ab.
In this embodiment, the first resin film 11ac is made of PET (Poly Ethylene Terephthalate).

Conducting wire 11d is made of silver. A portion of the conductive sheet 11a including the conductor 11d extends downward from the rectangle at the lower outer portion of the electrode portion 11 in the sheet width direction. is connected with

The terminal connecting member 11e is made of a conductive metal piece, and has one end to which the lead wire 11d is fastened and the other end to which the cable 11f is fastened.
The cable 11f is connected to a detection device 21, which will be described later.
The second resin film 11ab is made of carbon resin.
The ink 11aa is a metal ink containing BaTiO3 (barium titanate).

In the present embodiment, the conductive sheet 11a is formed with a total of six notches 11b, one at the center of the upper and lower edges and two at the left and right edges at intervals in the vertical direction. The cut portion 11b is formed in a semi-long hole shape having an arcuate edge.
In addition, between each of the two cut portions 11b formed on the left and right edges of the conductive sheet 11a in the left-right direction and between each of three crossing portions 11h above and below a crossing conductor 11db, which will be described later, each of the upper and lower A slot-shaped cut-out portion 11c extending in the direction is formed one by one. The cut-out portion 11c is formed vertically longer than the cut-out portion 11b, and is formed in a long hole shape having arc-shaped both edges.
Since the cutouts 11c are formed between the three crossings 11h in this manner, the bending load applied to the crossings 11h can be reduced by the cutouts 11c, and the conductor wire 11d is cut out from the crossings 11h. disconnection can be suppressed.
In addition, since the bending load in the seat width direction (short direction) can be relieved by the two notches 11b provided at the top and bottom, disconnection of the conductor 11d is prevented while forming the electrode portion 11 long in the seat width direction. can do.

The conducting wire 11d is composed of a basic conducting wire 11da arranged along the outer periphery of the electrode portion 11 and a crossing conducting wire 11db extending so as to intersect inside the basic conducting wire 11da.
More specifically, the cross conductors 11db connect the four corner portions of the basic conductors 11da with the portions along the notch portions 11b formed on the outer periphery of the electrode portion 11 extending in the vertical direction (longitudinal direction) of the sheet. It is stretched like this.
In particular, in the crossing conductor 11db, two crossing conductors 11db extend toward the basic conductors 11da along the cut portions 11b formed on both sides in the sheet width direction (short direction), and these are connected at different positions. It is arranged so that

As described above, since the cutout portion 11b and the cutout portion 11c are formed, the stress applied to the electrode portion 11 accompanying the bending of the skin material S1b is dispersed by the cutout portion 11b and the cutout portion 11c. . By dispersing the stress in this way, it is possible to suppress the electrode portion 11 from being locally bent at an acute angle, and prevent the electrode portion 11 from being wrinkled.
When the skin material S1b is bent by the notch part 11b and the cutout part 11c, the electrode part 11 is bent along the skin material S1b without generating wrinkles. Concentration of stress can be restricted, and disconnection of the conducting wire 11d can be prevented.

The conductors 11d are stretched in a planar manner so as to intersect the inside of the conductive sheet 11a, and at the intersection, two or less conductors 11d intersect, and three or more conductors 11d do not intersect.
In this way, the number of the conductors 11d that intersect at the intersection of the conductors 11d is suppressed to two or less, thereby making it possible to arrange the conductors 11d in a planar manner on the conductive sheet 11a while reducing the effects of disconnection. can be limited.

(About wiring pattern)
Here, the wiring pattern of the conducting wire 11d will be described with reference to FIG.
The basic pattern 18 shown in FIG. 5A includes a frame-shaped (rectangular in this example) basic conductor 18a formed along the outer periphery of each electrode portion, and extending from the four corners of the basic conductor 18a to the opposite corners. It is composed of a cross conductor 18b that intersects with each other.
The cross conductors 18b extend from the four corners of the basic conductors 18a, which have high rigidity and are less susceptible to bending loads, thereby suppressing disconnection.
In addition, when the conductive sheet is formed with cuts, the basic pattern 18 is formed along the inside of the edges of the cuts.

The connecting pattern 19 shown in FIG. 5(B) has a shape in which two basic patterns 18 are connected adjacently. has no basic conducting wire 18a (basic conducting wires 19aa and 19ba to be described later).
Here, the square portion 19a is formed by a basic conductor wire 19aa provided on the outer circumference of the square other than the side adjacent to the square portion 19b and a cross conductor wire 19ab extending so as to intersect the inside of the basic conductor wire 19aa. It is configured.
Similarly, the square portion 19b is formed by a basic conductor 19ba provided on the outer periphery of the square other than the side adjacent to the square portion 19a and a cross conductor 19bb extending so as to intersect the inside of the basic conductor 19ba. It is configured.
In other words, as shown in the connection pattern 19, each electrode portion is configured so that a plurality of basic patterns 18 are arranged side by side, and the basic conductor wire 18a is not arranged in the connection portion 19c.
By configuring in this way, it is possible to evenly arrange the conductive wires in the electrode portion, and to save expensive silver, which is the material of the conductive wires, by not providing the conductive wires in the connecting portion 19c.

(About other configurations)
The detection device 21 shown in FIG. 1 detects a biosignal related to an electrocardiographic signal from the potential signal detected by the electrode unit 11 and the reference potential supplied from the conductive cloth 26, and detects respiration from the pressure signal obtained from the respiration sensor 9. It detects biological signals related to signals, and is composed of a ferrite core (not shown), a common mode noise filter, an operational amplifier, and the like.
The ferrite core and common mode noise filter are attached to the DC power supply line and have the function of removing conduction noise.

The arithmetic processing unit 22 compares the respiratory signal and the electrocardiogram signal related to the biological signals detected by the detection unit 21 with respective predetermined reference values, and judges that the awakening degree (consciousness level) of the seated person has decreased. If so, it transmits a drive signal to the vibration device 23 .

The vibrating device 23 is a device equipped with a so-called "vibrating motor" consisting of a known unbalanced mass motor, and drives the vibrating motor for a predetermined time according to the drive signal received from the arithmetic processing unit 22, thereby stimulating the seated person with vibration. to give For example, the vibration device 23 is provided inside the seat back S1.

The heart rate sensor 10 of the vehicle seat S according to the present embodiment compares potential signals detected from a pair of electrode portions 11 provided on the seat back S1 and close to the heart. can be reduced.
The electrode portion 11 of the heartbeat sensor 10 may be provided on the seat cushion S2.

Furthermore, since the respiratory sensor 9 provided on the back side of the seat cushion S2 is arranged at a portion facing the seated person's buttocks, the contact between the respiratory sensor 9 and the seated person is easily maintained and stable. It is possible to detect respiratory signals.
Then, the processing unit 22 uses both the signals detected by the respiratory sensor 9 and the heartbeat sensor 10 to determine the arousal state of the seated person, so that determination accuracy can be further improved.

In the above embodiment, the vibrating device has been described as an example of the wakefulness maintaining device, but the present invention is not limited to such a configuration. For example, using a display, light, buzzer, etc. provided in the vehicle to notify the seated occupant or fellow passenger by video, light, or sound, so as to directly or indirectly keep the seated occupant awake. good too.

Furthermore, in the above embodiment, a vehicle seat has been described as an example, but the present invention is not limited to such a configuration, and can be applied to seats used for industrial equipment, airplanes, ships, theaters, and other applications. It is possible to

S vehicle seat S1 seat back S1a cushion pad S1b skin material S2 seat cushion S2a cushion pad S2b skin material U wakefulness maintenance device 9 respiration sensor 10 heartbeat sensor 11 electrode part 11a conductive sheet 11aa ink 11ab second resin film 11ac first resin film 11ad double-faced tape 11b notch 11c cutout 11d conducting wire 11da basic conducting wire (partial)
11db cross conductor (other part)
11e Terminal connecting member 11f Cable 11h Intersection 18 Basic pattern 18a Basic conductor 18b Cross conductor 19 Connection pattern 19a, 19b Square part
19aa, 19ba basic conductor
19ab, 19bb cross conductors
19c connecting portion 21 detection device 22 arithmetic processing device 23 vibration device 26 conductive cloth

Claims (5)

a heartbeat sensor having an electrode unit for detecting a potential signal corresponding to the electrocardiographic potential of a seated person;
an arithmetic processing unit that performs an arithmetic operation for specifying the consciousness level of the seated person based on the potential signal obtained from the heartbeat sensor,
The electrode part is composed of a conductive sheet and a plurality of conducting wires,
The plurality of conductors includes a portion arranged along the periphery of the conductive sheet and a plurality of other portions that intersect with the portion,
The electrode portion is formed in a rectangular sheet shape elongated in one direction,
In the conductive sheet, cut portions are formed so as to form a pair in the short direction on the side extending in the long direction at the peripheral edge of the electrode portion,
The plurality of other portions of the conductive wire extend from one of the four corners of the electrode portion to the opposing cut portion toward the inside of the portion disposed along the periphery of the conductive sheet. , intersects at a plurality of positions inside the part disposed along the periphery of the conductive sheet,
The seat has a seat back that serves as a backrest for the seated person,
The seat back further includes a pad and a skin material covering the pad, and the pad of the seat back includes a narrow portion narrowed in the seat width direction and a wide portion wider than the narrow portion. and
The electrode portion extends long in the extending direction of the sheet, and the conductive sheet has a conductive sheet narrow portion with a narrow width in the sheet width direction,
The electrode portion is arranged over the narrow portion and the wide portion of the pad, and the narrow portion of the conductive sheet is arranged in the narrow portion of the pad. . The surface of the pad is divided into a plurality of areas by boundary lines,
2. The sheet according to claim 1, wherein the electrode section of the heartbeat sensor is arranged within one of the plurality of areas without crossing the boundary line. A seat cushion on which the seated person sits , and a breathing sensor ,
3. The seat according to claim 1, wherein the respiration sensor is provided on the seat cushion. The surface of the pad that constitutes the seat cushion is divided into a plurality of areas by boundary lines,
4. The seat according to claim 3, wherein the respiration sensor is arranged within one of the plurality of zones without crossing the boundary line. 5. The sheet according to any one of claims 1 to 4, wherein the conductive sheet is formed with a cut portion different from the cut portion at an intermediate portion on the short side of the electrode portion. .

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