JP7235951B2 - Seating sensor - Google Patents

Description

The present invention relates to a seating sensor for detecting that an occupant is seated.

2. Description of the Related Art There is known a seat sensor that is provided with a plurality of pressure-sensitive switches in a seating area of a vehicle seat and switches between on and off in response to seating of a passenger (for example, Japanese Patent Application Laid-Open No. 2002-200002). The seating sensor described in Patent Document 1 includes a flexible sheet material, a plurality of pressure-sensitive switches provided on the sheet material, and wiring provided on the sheet material and connecting the plurality of pressure-sensitive sensors. have. The pressure-sensitive switches are arranged in pairs on the left and right and are connected in series to form one detection unit. A plurality of detectors are arranged in the front and rear and connected in parallel with each other. In at least one detection section, when both pressure-sensitive switches are turned on, the detection circuit becomes conductive and the seating sensor is turned on. Since a plurality of detection units are arranged in a row in the front-rear direction, even if the passenger is seated on the front side or the rear side of the seating area, the seat sensor can detect that the passenger is seated. .

Japanese Patent Publication No. 2007-526844

When a plurality of pressure-sensitive sensors are arranged close to each other on a continuous sheet, when a load is applied within the detection range of one pressure-sensitive sensor, the sheet is deformed due to the stress applied to the sheet, and other sensors are affected. The pressure sensor may also erroneously detect the load.

In view of the above background, an object of the present invention is to suppress erroneous detection in a seating sensor.

In order to solve the above problems, a seat cushion (2) of a vehicle seat (1) is provided between an upper surface of a seat cushion pad (6) and a skin material (7) covering the seat cushion pad. A seating sensor (10) comprising a flexible sheet material (11), a plurality of pressure-sensitive switches (12) provided on the sheet material, and a plurality of pressure-sensitive switches (12) provided on the sheet material. wiring (13) for connecting a switch, and the sheet material has a main portion (11A) extending left and right and a plurality of branch portions (11B to 11J) extending forward or backward from the main portion. and the plurality of pressure-sensitive switches are provided at respective ends of the branched portions.

According to this aspect, adjacent pressure-sensitive switches are connected via the branch portion, the main portion, and the branch portion. Therefore, when a load is applied to a certain pressure-sensitive switch, the deformation of the branched portion provided with that pressure-sensitive switch is less likely to be transmitted to the adjacent branched portion provided with another pressure-sensitive switch. Therefore, erroneous detection of other adjacent pressure-sensitive switches can be suppressed.

In the above aspect, the main portion extends from the left half to the right half of the occupant's seating area (5), and the branch portions are arranged laterally spaced from each other in the left half of the seating area. A first branched portion (11B) and a second branched portion (11C), and a third branched portion (11D) and a fourth branched portion (11E ), and the pressure-sensitive switches include a first pressure-sensitive switch (12B) provided at the tip of the first branch and a second pressure-sensitive switch (12C) provided at the tip of the second branch. , a third pressure-sensitive switch (12D) provided at the tip of the third branch, and a fourth pressure-sensitive switch (12E) provided at the tip of the fourth branch, and the first to The fourth pressure-sensitive switch is preferably arranged on the first imaginary straight line (L1) extending left and right.

According to this aspect, erroneous detection of each pressure-sensitive switch can be suppressed when the first to fourth pressure-sensitive switches are arranged close to each other on the left and right.

Said aspect WHEREIN: It is good to arrange|position a passenger|crew's hip point (HP) on the said 1st imaginary straight line.

According to this aspect, the first to fourth pressure-sensitive switches can be arranged at the portion where the passenger's load is most likely to be applied.

In the above aspect, the wiring connects the first pressure-sensitive switch and the second pressure-sensitive switch in parallel to form a first circuit (16), and connects the third pressure-sensitive switch and the fourth pressure-sensitive switch. A pressure switch may be connected in parallel to form a second circuit (17), and said first circuit and said second circuit may be connected in series.

According to this aspect, the seating sensor can reliably detect the occupant even when there is a difference in the physique of the occupant or the seating position of the occupant is shifted to the left or right.

In the above aspect, the first branch portion and the first pressure-sensitive switch are arranged to the left of the second branch portion and the second pressure-sensitive switch, and the third branch portion and the third pressure-sensitive switch are arranged to the left. The switch is arranged to the left of the fourth branch portion and the fourth pressure-sensitive switch, the first pressure-sensitive switch has a larger ON load than the second pressure-sensitive switch, and the fourth pressure-sensitive switch is It is preferable that the load for turning on the switch is larger than that of the third pressure-sensitive switch.

According to this aspect, the seating sensor is less likely to erroneously detect an object other than the passenger. Since the left and right outer pressure-sensitive switches, that is, the first and fourth pressure-sensitive switches are used to detect a passenger with a large build, they can detect a passenger even if the load that is turned on is greater than that of the inner sensor. can be done. By increasing the load at which the left and right outer pressure-sensitive switches are turned on, it is possible to prevent the pressure-sensitive switches from being turned on by an object lighter than the occupant.

In the above-described aspect, the first to fourth branched portions extend rearward from the main portion, and the branched portion is a fifth branched portion extending forward at a left-right half of the seating area with a space left and right from each other. a portion (11F) and a sixth branched portion (11G), and a seventh branched portion (11H) and an eighth branched portion (11J) extending forward at a left-right interval from each other in the right half of the seating area; The pressure-sensitive switches include a fifth pressure-sensitive switch (12F) provided at the tip of the fifth branch, a sixth pressure-sensitive switch (12G) provided at the tip of the sixth branch, and the A seventh pressure-sensitive switch (12H) provided at the tip of the seven-branched portion and an eighth pressure-sensitive switch (12J) provided at the tip of the eighth-branched portion, The pressure switch is preferably arranged on the second imaginary straight line (L2) extending left and right.

According to this aspect, it is possible to form a rear switch row composed of the first to fourth pressure-sensitive switches and a front switch row composed of the fifth to eighth pressure-sensitive switches. The occupant can be reliably detected even when it is shifted forward or backward.

In the above aspect, the wiring connects the fifth pressure-sensitive switch and the sixth pressure-sensitive switch in parallel to form a third circuit (18), and connects the seventh pressure-sensitive switch and the eighth pressure-sensitive switch in parallel. the pressure switch in parallel to form a fourth circuit (19), the third circuit and the fourth circuit are connected in series, the first circuit and the second circuit and the third circuit and It is preferable to connect the fourth circuit in parallel.

According to this aspect, the front switch row composed of the fifth to eighth pressure-sensitive switches can reliably detect the occupant even when there is a difference in the physique of the occupant or a lateral shift in the seating position of the occupant. can be done.

In the above aspect, the fifth branch portion and the fifth pressure-sensitive switch are arranged to the left of the sixth branch portion and the sixth pressure-sensitive switch. The switch is arranged to the left of the eighth branch portion and the eighth pressure-sensitive switch, the fifth pressure-sensitive switch has a larger ON load than the sixth pressure-sensitive switch, and the eighth pressure-sensitive switch It is preferable that the load for turning on the switch is larger than that of the seventh pressure-sensitive switch.

According to this aspect, the front switch row composed of the fifth to eighth pressure-sensitive switches is less likely to erroneously detect an object other than the passenger.

In the above aspect, the first branch portion and the fifth branch portion are arranged in a straight line in the front-rear direction, the second branch portion and the sixth branch portion are arranged in a straight line in the front-rear direction, and the third branch portion and the It is preferable that the seventh branching portion is arranged in a straight line in the front-rear direction, and the fourth branching portion and the eighth branching portion are arranged in a straight line in the front-rear direction.

According to this aspect, the shape of the sheet material can be simplified.

In the above aspect, the branched portion has a ninth branched portion (11K) extending forward or backward from the main portion and having a connection portion (14) with an external wiring at its tip, and the connection portion is , and may be arranged behind the second imaginary straight line and forward of the first imaginary straight line.

According to this aspect, the width of the entire seating sensor in the front-rear direction can be reduced, and the seating sensor can be formed compactly.

In the above aspect, the vehicle seat may constitute a rear seat of an automobile.

According to this configuration, it is possible to detect that the passenger is seated by using the seat sensor in the rear seat where the posture of the passenger can change greatly.

According to a mode in which the sheet material has a main portion extending left and right and a plurality of branch portions extending forward or rearward from the main portion, and a plurality of pressure-sensitive switches are provided at the tips of the branch portions, Adjacent pressure-sensitive switches are connected via a branch portion, a main portion and a branch portion. Therefore, when a load is applied to one of the pressure-sensitive switches, the deformation of the branched portion provided with that pressure-sensitive switch is less likely to be transmitted to the adjacent branched portion provided with the other pressure-sensitive switch. Therefore, erroneous detection by other adjacent pressure-sensitive switches can be suppressed.

The branching portions include a first branching portion and a second branching portion which are arranged with a left-right spacing from each other in the left half of the seating area, and a first branching portion and a second branching portion which are arranged with a left-right spacing from each other in the right half of the seating area. According to the aspect in which the first to fourth pressure-sensitive switches are arranged on the first imaginary straight line extending left and right, the first to fourth pressure-sensitive switches extend left and right. False detection of each pressure-sensitive switch can be suppressed when they are arranged close to each other.

According to the aspect in which the occupant's hip point is arranged on the first imaginary straight line, the first to fourth pressure-sensitive switches can be arranged at the portion where the occupant's load is most likely to be applied.

A wiring connects the first pressure-sensitive switch and the second pressure-sensitive switch in parallel to form a first circuit, and connects the third pressure-sensitive switch and the fourth pressure-sensitive switch in parallel to form a second circuit. According to the aspect in which the first circuit and the second circuit are connected in series, the seating sensor can reliably detect the occupant regardless of the physique difference of the occupant or the deviation of the seating position of the occupant to the left or right. can be done.

According to the aspect, the load for turning on the first pressure-sensitive switch is larger than that for the second pressure-sensitive switch, and the load for turning on the fourth pressure-sensitive switch is larger than that for the third pressure-sensitive switch. It becomes difficult to erroneously detect an object. By increasing the load at which the left and right outer pressure-sensitive switches are turned on, it is possible to prevent the pressure-sensitive switches from being turned on by an object lighter than the occupant.

The branched portions include a fifth branched portion and a sixth branched portion extending forwardly in the left half of the seating area while being spaced laterally from each other, and a branching portion extending forwardly in the right half of the seating area while being spaced horizontally from each other. and the fifth to eighth pressure-sensitive switches are arranged on the second imaginary straight line extending left and right. To reliably detect an occupant even when the seating position of the occupant is displaced forward and backward by forming a rear switch row consisting of fifth to eighth pressure-sensitive switches and a front switch row consisting of fifth to eighth pressure-sensitive switches. can be done.

A wiring connects the fifth pressure-sensitive switch and the sixth pressure-sensitive switch in parallel to form a third circuit, and connects the seventh pressure-sensitive switch and the eighth pressure-sensitive switch in parallel to form a fourth circuit. and connecting the third circuit and the fourth circuit in series, and connecting the first circuit and the second circuit and the third circuit and the fourth circuit in parallel. The front switch row consisting of switches can reliably detect the occupant even if there is a difference in physique of the occupant or if the seating position of the occupant is shifted to the left or right.

According to the aspect, the load for turning on the fifth pressure-sensitive switch is larger than that for the sixth pressure-sensitive switch, and the load for turning on the eighth pressure-sensitive switch is larger than that for the seventh pressure-sensitive switch. The front switch row composed of pressure switches is less likely to erroneously detect an object other than the passenger.

The first branched portion and the fifth branched portion are arranged linearly in the front-rear direction, the second branched portion and the sixth branched portion are arranged linearly in the front-rear direction, and the third branched portion and the seventh branched portion are linearly arranged in the front-rear direction. According to the aspect in which the fourth branched portion and the eighth branched portion are arranged in a straight line in the front-rear direction, the shape of the sheet material can be simplified.

According to the aspect in which the connection portion provided at the tip of the ninth branch portion is arranged behind the second imaginary straight line and forward of the first imaginary straight line, the front-to-rear width of the entire seating sensor can be reduced, The sensor can be made compact.

According to the configuration in which the vehicle seat constitutes the rear seat of the automobile, the seat sensor can be used to detect that the passenger is seated in the rear seat where the posture of the passenger can change significantly.

A plan view of the rear seat according to the embodiment Side view of the rear seat according to the embodiment A plan view of the seating sensor provided in the rear seat Seat sensor circuit diagram

An embodiment in which a vehicle seat occupancy sensor according to the present invention is applied to a occupancy sensor for a second or third row rear seat of an automobile will be described below with reference to the drawings.

As shown in FIG. 1, a seat 1 includes a seat cushion 2 provided on the floor of an automobile, a pair of left and right seat backs 3 supported at the rear of the seat cushion 2, and a pair of seat backs 3 provided above each seat back 3. It has two headrests 4 . The seat cushion 2 extends left and right to form two seating areas 5 corresponding to two passengers.

As shown in FIG. 2 , the seat cushion 2 has a seat cushion pad 6 and a skin material 7 covering the surface of the seat cushion pad 6 . The seat cushion pad 6 may be directly supported by the floor panel of the automobile, or may be supported by a frame member supported by the floor panel. In this embodiment, a sheet-shaped wadding material 8 is provided between the upholstery material 7 and the seat cushion pad 6 . The wadding material 8 may be omitted.

As shown in FIG. 2 , the upper surface of the seat cushion 2 slopes downward toward the rear in each seating area 5 . Each seating area 5 supports the occupant's buttocks and thighs.

As shown in FIGS. 1 and 3, each seating area 5 is provided with a seating sensor 10 for detecting seating of an occupant. The seat sensor 10 corresponds to a switch that is conductive when the passenger is seated and cut off when the passenger is not seated. The seating sensor 10 includes a flexible sheet material 11, a plurality of pressure-sensitive switches 12 provided on the sheet material 11, and wiring 13 provided on the sheet material 11 and connecting the plurality of pressure-sensitive switches. have.

A sheet material 11 is arranged between the wadding material 8 and the seat cushion pad 6 . The sheet material 11 may be, for example, a flexible printed circuit board. The sheet material 11 has a main portion 11A extending left and right, and a plurality of branch portions 11B to 11J extending forward or rearward from the main portion 11A. The main portion 11A extends linearly from the left half of the occupant's seating area 5 to the right half thereof. The center of the main portion 11</b>A in the left-right direction is arranged on the front-rear line passing through the center of the seating area 5 .

In the present embodiment, the branched portions 11B to 11J include a first branched portion 11B, a second branched portion 11C, a third branched portion 11D, and a fourth branched portion 11E extending rearward from the main portion 11A. It has a fifth branched portion 11F, a sixth branched portion 11G, a seventh branched portion 11H, and an eighth branched portion 11J extending forward. In this embodiment, the main portion 11A and the first to eighth branch portions 11B to 11J are orthogonal to each other.

The first branched portion 11B, the second branched portion 11C, the third branched portion 11D, and the fourth branched portion 11E are arranged in order from the left side at intervals in the left and right direction. The first branched portion 11B and the second branched portion 11C are arranged in the left half of the seating area 5, and the third branched portion 11D and the fourth branched portion 11E are arranged in the right half of the seating area. The left and right distances of the first branch portion 11B and the second branch portion 11C and the left and right distances of the third branch portion 11D and the fourth branch portion 11E are set equal to each other. The left and right distances of the second branch portion 11C and the third branch portion 11D are set larger than the left and right distances of the first branch portion 11B and the second branch portion 11C. The left and right distances of the second branch portion 11C and the third branch portion 11D are preferably two to three times the left and right distances of the first branch portion 11B and the second branch portion 11C.

The fifth branched portion 11F, the sixth branched portion 11G, the seventh branched portion 11H, and the eighth branched portion 11J are arranged in order from the left side at intervals in the left and right direction. The fifth branched portion 11F and the sixth branched portion 11G are arranged in the left half of the seating area 5, and the seventh branched portion 11H and the eighth branched portion 11J are arranged in the right half of the seating area. The fifth branching portion 11F is linearly aligned with the first branching portion 11B, the sixth branching portion 11G is linearly aligned with the second branching portion 11C, and the seventh branching portion 11H is aligned with the third branching portion 11D. They are arranged linearly in the front-rear direction, and the eighth branched portion 11J and the fourth branched portion 11E are linearly arranged in the front-rear direction. The left and right intervals between the fifth branch portion 11F and the sixth branch portion 11C and the left and right intervals between the seventh branch portion 11H and the eighth branch portion 11J are respectively equal to the distance. The horizontal distance between the sixth branch portion 11C and the seventh branch portion 11H is equal to the horizontal distance between the second branch portion 11C and the third branch portion 11D.

The first to fourth branches 11B to 11E have lengths equal to each other. The fifth to eighth branches 11F to 11J have the same length. The first through eighth branches 11B through 11J may have lengths equal to each other.

A ninth branch portion 11K extending forward is provided in the center of the main portion 11A in the left-right direction. The front end of the ninth branch portion 11K is provided with a connection portion 14 for connection with a harness 21, which is an external wiring. The ninth branched portion 11K is preferably shorter than the fifth to eighth branched portions 11F to 11J.

In this embodiment, the multiple pressure-sensitive switches 12 include first to eighth pressure-sensitive switches 12B to 12J. Each pressure-sensitive switch 12 is a membrane switch, and includes a frame-shaped spacer sheet, contact sheets stacked with a space between each other via the frame-shaped spacer sheet, and contact sheets provided on the surfaces facing each other. and electrical contacts. When the pressure-sensitive switch 12 receives a load from the outside, the contact sheet bends and the two contacts come into contact with each other to turn on. The pressure at which the contacts contact each other can be varied by adjusting the size and thickness of the contacts, the thickness and shape of the spacers, the hardness of the contact sheet, and the like. Each pressure-sensitive switch 12 may have any configuration as long as it is a switch that detects pressure and electrically conducts.

As shown in FIG. 3, the first pressure-sensitive switch 12B is provided at the tip (rear end) of the first branch portion 11B, and the second pressure-sensitive switch 12C is provided at the tip (rear end) of the second branch portion 11C. , the third pressure-sensitive switch 12D is provided at the tip (rear end) of the third branch portion 11D, the fourth pressure-sensitive switch 12E is provided at the tip (rear end) of the fourth branch portion 11E, and the fifth pressure-sensitive switch 12F is provided at the tip (front end) of the fifth branch portion 11F, the sixth pressure-sensitive switch 12G is provided at the tip (front end) of the sixth branch portion 11G, and the seventh pressure-sensitive switch 12H is provided at the tip (front end) of the seventh branch portion 11H. The eighth pressure-sensitive switch 12J is provided at the tip (front end) of the eighth branch portion 11J.

The first to fourth pressure sensitive switches 12B to 12E are arranged on a first imaginary straight line L1 extending left and right. The fifth to eighth pressure-sensitive switches 12F to 12J are arranged on a second imaginary straight line L2 extending left and right. The first imaginary straight line L1, the second imaginary straight line L2, and the main portion 11A are arranged parallel to each other. The first imaginary straight line L1 is arranged behind the main portion 11A, and the second imaginary straight line L2 is arranged ahead of the main portion 11A.

An occupant's hip point HP is arranged on the first imaginary straight line L1. The hip point HP is set based on the American SAE standard J-826, and is the rotation center point (hip joint position) connecting the torso and thighs of the three-dimensional mannequin. In a plan view, the center point of a line segment connecting two rotation center points.

It is preferable that the front edge of the connection portion 14 provided at the front end of the ninth branch portion 11K is arranged behind the second imaginary straight line L2 and ahead of the first imaginary straight line L1. As a result, the front-to-rear width of the entire seating sensor 10 can be reduced.

As shown in FIG. 4, the wiring 13 provided on the sheet material 11 connects the first to eighth pressure sensitive switches 12B to 12J to form a detection circuit 15. FIG. The wiring 13 connects the first pressure-sensitive switch 12B and the second pressure-sensitive switch 12C in parallel to form a first circuit 16, and connects the third pressure-sensitive switch 12D and the fourth pressure-sensitive switch 12E in parallel. to form the second circuit 17, and the first circuit 16 and the second circuit 17 are connected in series. The wiring 13 connects the fifth pressure-sensitive switch 12F and the sixth pressure-sensitive switch 12G in parallel to form a third circuit 18, and connects the seventh pressure-sensitive switch 12H and the eighth pressure-sensitive switch 12J in parallel. to form a fourth circuit 19, and the third circuit 18 and the fourth circuit 19 are connected in series. The wiring 13 connects the first circuit 16 and the second circuit 17 and the third circuit 18 and the fourth circuit 19 in parallel to form the detection circuit 15 . Both ends of the wiring 13 are provided in the connecting portion 14 and connected to the control device 22 via the harness 21 . The harness 21 extends below the seat cushion pad 6 through a passage 23 that vertically penetrates the seat cushion pad 6 . The upper end of the passage 23 is preferably arranged on the second imaginary straight line L2 or behind the second imaginary straight line L2. As a result, the passage 23 can be formed closer to the seating sensor 10, and the range in which the harness 21 is arranged on the upper surface of the seat cushion pad 6 can be reduced. Also, the seating sensor 10 and the passage 23 can be arranged compactly.

The load for turning on the first pressure-sensitive switch 12B is set larger than that for the second pressure-sensitive switch 12C, and the load for turning on the fourth pressure-sensitive switch 12E is set larger than that for the third pressure-sensitive switch 12D. It is preferable that the first pressure-sensitive switch 12B and the fourth pressure-sensitive switch 12E have the same ON load, and the second pressure-sensitive switch 12C and the third pressure-sensitive switch 12D have the same ON load. should be set to The load for turning on the fifth pressure-sensitive switch 12F is set larger than that for the sixth pressure-sensitive switch 12G, and the load for turning on the eighth pressure-sensitive switch 12J is set larger than that for the seventh pressure-sensitive switch 12H. It is preferable that the fifth pressure-sensitive switch 12F and the eighth pressure-sensitive switch 12J have the same ON load, and the sixth pressure-sensitive switch 12G and the seventh pressure-sensitive switch 12H have the same ON load. should be set to Further, it is preferable that the first pressure-sensitive switch 12B and the fifth pressure-sensitive switch 12F are set to have the same ON load, and the second pressure-sensitive switch 12C and the sixth pressure-sensitive switch 12G are set to the ON load. should be set to be the same.

The position of each pressure sensitive switch 12 is illustrated below. The distance between the second pressure-sensitive switch 12C and the third pressure-sensitive switch 12D in the left-right direction is preferably 60 mm or more and 100 mm or less. The distance between the first pressure-sensitive switch 12B and the second pressure-sensitive switch 12C and the distance between the third pressure-sensitive switch 12D and the fourth pressure-sensitive switch 12E are preferably 30 mm or more and 50 mm or less. The distance between the first pressure-sensitive switch 12B and the fifth pressure-sensitive switch 12F in the front-rear direction is preferably 60 mm or more and 80 mm or less.

The control device 22 determines whether or not the passenger is seated based on the conductive state (on, off) of the seating sensor 10 . Furthermore, the control device 22 determines whether the seat belt is being fastened in each seating area 5 . When the control device 22 determines that the occupant is seated in the seating area 5 and the seatbelt is not fastened, the occupant is warned by voice, lighting of an alarm light, or the like.

Next, the effects of the seating sensor 10 according to this embodiment will be described. The sheet material 11 has a main portion 11A extending left and right, and first to eighth branch portions 11B to 11J extending forward or backward from the main portion 11A. Since they are provided at the tips of the first to eighth branch portions 11B to 11J, respectively, the adjacent pressure-sensitive switches 12B to 12J are connected via the branch portions 11B to 11J and the main portion 11A. Therefore, when a load is applied to a certain pressure-sensitive switch 12B-12J, the branching portions 11B-11J provided with the pressure-sensitive switch 12B-12J are deformed so that the adjacent pressure-sensitive switches 12B-12J are provided. It becomes difficult to be transmitted to the branch portions 11B to 11J. Therefore, erroneous detection of the other adjacent pressure sensitive switches 12B to 12J can be suppressed. In particular, in a mode in which the pressure-sensitive switches 12 are arranged in a straight line to the left and right, such as the first to fourth pressure-sensitive switches 12B to 12E or the fifth to eighth pressure-sensitive switches 12F to 12J, the sheet material It is possible to prevent erroneous detection of each pressure-sensitive switch 12 due to deformation of pressure-sensitive switches 11 .

Since the occupant's hip point HP is arranged on the first imaginary straight line L1, the first to fourth pressure-sensitive switches 12B to 12E can be arranged at portions where the occupant's load is most likely to be applied.

When at least one of the first pressure-sensitive switch 12B and the second pressure-sensitive switch 12C is turned on and at least one of the third pressure-sensitive switch 12D and the fourth pressure-sensitive switch 12E is turned on, the detection circuit 15 is turned on. Since the seating sensor 10 is configured to detect the occupant, the seating sensor 10 can reliably detect the occupant even when there is a difference in the physique of the occupant or there is a lateral shift in the seating position of the occupant. For example, if the occupant has a large physique, all of the first to fourth pressure-sensitive switches 12B to 12E or the first and fourth pressure-sensitive switches 12B and 12E are turned on and the detection circuit 15 is turned on. When the occupant has a small physique such as a child, the second and third pressure-sensitive switches 12C and 12D are turned on and the detection circuit 15 is turned on. Also, when the occupant is seated with a shift to the left, at least one of the first and second pressure-sensitive switches 12B and 12C and the third pressure-sensitive switch 12D are turned on and the detection circuit 15 is conducted. When the occupant is seated shifted to the right, at least one of the third and fourth pressure-sensitive switches 12D and 12E and the second pressure-sensitive switch 12C are turned on, and the detection circuit 15 is conducted.

In addition, since the front switch row composed of the fifth to eighth pressure sensitive switches 12F to 12J is provided in front of the rear switch row composed of the first to fourth pressure sensitive switches 12B to 12E, the occupant is seated with a forward displacement. Even in this case, the seat sensor 10 can reliably detect the occupant by the front switch row.

The load for turning on the first pressure-sensitive switch 12B is larger than that for the second pressure-sensitive switch 12C, and the load for turning on the fourth pressure-sensitive switch 12E is larger than that for the third pressure-sensitive switch 12D. The sensor 10 can suppress erroneous detection of an object other than a passenger as a passenger. When the occupant shifts to the left or right when seated, the load applied to the pressure-sensitive switch 12 located outside the direction of shift (the first pressure-sensitive switch 12B when the occupant shifts to the left when seated) is determined by the occupant. This is larger than the load received by the pressure-sensitive switches 12C and 12D located on the left and right inner sides when the user is seated at the right position. In addition, when the occupant has a large physique and a load is applied to the left and right pressure-sensitive switches 12B and 12E, the occupant's physique is smaller than when the occupant is small and a load is applied to the left and right inner pressure-sensitive switches 12C and 12D. The load applied due to body weight increases. Therefore, the load that turns on the first and fourth pressure-sensitive switches 12B and 12E positioned on the left and right outer sides is set larger than the load that turns on the second and third pressure-sensitive switches 12C and 12D positioned on the left and right inner sides. occupants can be detected. By making the load that turns on the first and fourth pressure-sensitive switches 12B and 12E on the left and right outer sides larger than the load that turns on the second and third pressure-sensitive switches 12C and 12D on the left and right inner sides, an object lighter than the occupant can suppress turning on of the first and fourth pressure-sensitive switches 12B and 12E. The fifth to eighth pressure-sensitive switches 12F to 12J arranged on the front side have the same effect.

Although the specific embodiments have been described above, the present invention is not limited to the above embodiments and can be widely modified. The ninth branch portion 11K may extend rearward from the center of the main portion 11A. In this case, the connection portion 14 may be provided at the rear end of the ninth branch portion 11K, and the connection portion 14 may be arranged forward of the first imaginary straight line L1. Also, the ninth branch portion 11K may extend leftward from the left end of the main portion 11A, or may extend rightward from the right end of the main portion 11A. Each branch 11B-11K may be curved or bent.

1: Seat 2: Seat cushion 5: Seating area 6: Seat cushion pad 7: Skin material 10: Seat sensor 11: Seat material 11A: Main portions 11B to 11K: First to ninth branch portions 12B to 12J: First to Eighth pressure-sensitive switch 13 : Wiring 14 : Connection part 16 : First circuit 17 : Second circuit 18 : Third circuit 19 : Fourth circuit 22 : Control device HP : Hip point L1 : First imaginary straight line L2 : Second imaginary straight line

Claims (9)

A seating sensor provided between an upper surface of a seat cushion pad constituting a seat cushion of a vehicle seat and a skin material covering the seat cushion pad,
a flexible sheet material;
a plurality of pressure-sensitive switches provided on the sheet material;
a wiring provided on the sheet material and connecting the plurality of pressure-sensitive switches;
The sheet material has a main portion extending left and right and a plurality of branch portions extending forward or rearward from the main portion,
The plurality of pressure-sensitive switches are provided at respective ends of the branched portions ,
The main portion extends from the left half to the right half of the occupant's seating area,
The branched portions are arranged in the left half of the seating area with a first branch and a second branch in the left half of the seating area, and in the right half of the seating area with a horizontal distance from each other. the third branch and the fourth branch,
The pressure-sensitive switches include a first pressure-sensitive switch provided at the tip of the first branched portion, a second pressure-sensitive switch provided at the tip of the second branched portion, and a pressure-sensitive switch provided at the tip of the third branched portion. a third pressure-sensitive switch provided, and a fourth pressure-sensitive switch provided at the tip of the fourth branch,
The first to fourth pressure-sensitive switches are arranged on a first imaginary straight line extending left and right,
The wiring connects the first pressure-sensitive switch and the second pressure-sensitive switch in parallel to form a first circuit, and connects the third pressure-sensitive switch and the fourth pressure-sensitive switch in parallel. forming a second circuit, and connecting the first circuit and the second circuit in series. 2. The seating sensor according to claim 1 , wherein the hip point of the occupant is arranged on the first imaginary straight line. The first branch portion and the first pressure-sensitive switch are arranged to the left of the second branch portion and the second pressure-sensitive switch, and the third branch portion and the third pressure-sensitive switch are arranged at the arranged to the left of the 4-branching portion and the fourth pressure-sensitive switch,
The first pressure-sensitive switch has a larger ON load than the second pressure-sensitive switch,
2. The seating sensor according to claim 1, wherein said fourth pressure-sensitive switch is turned on with a larger load than said third pressure-sensitive switch. The first to fourth branch portions extend rearward from the main portion,
The branched portions include a fifth branched portion and a sixth branched portion extending forward and leftwardly spaced apart from each other in the left half of the seating area, and a leftwardly spaced apart from each other in the right half of the seating area. a seventh branch and an eighth branch extending forward;
The pressure-sensitive switches include a fifth pressure-sensitive switch provided at the tip of the fifth branch, a sixth pressure-sensitive switch provided at the tip of the sixth branch, and a tip of the seventh branch. a seventh pressure-sensitive switch provided; and an eighth pressure-sensitive switch provided at the tip of the eighth branch,
4. The seating sensor according to claim 3 , wherein the fifth to eighth pressure-sensitive switches are arranged on a second imaginary straight line extending left and right. The wiring connects the fifth pressure-sensitive switch and the sixth pressure-sensitive switch in parallel to form a third circuit, and connects the seventh pressure-sensitive switch and the eighth pressure-sensitive switch in parallel. forming a fourth circuit, connecting the third circuit and the fourth circuit in series, and connecting the first circuit and the second circuit and the third circuit and the fourth circuit in parallel The seating sensor according to claim 4 , characterized by: The fifth branch portion and the fifth pressure-sensitive switch are arranged to the left of the sixth branch portion and the sixth pressure-sensitive switch, and the seventh branch portion and the seventh pressure-sensitive switch are arranged at the arranged to the left of the eighth branch and the eighth pressure-sensitive switch,
The fifth pressure-sensitive switch has a larger load to be turned on than the sixth pressure-sensitive switch,
6. The seating sensor according to claim 5, wherein the eighth pressure-sensitive switch is turned on with a larger load than the seventh pressure-sensitive switch. The first branching portion and the fifth branching portion are linearly arranged in the front-rear direction, the second branching portion and the sixth branching portion are linearly arranged in the front-rear direction, and the third branching portion and the seventh branching portion are arranged linearly in the front-rear direction. 7. The seating sensor according to claim 6, wherein the fourth branched portion and the eighth branched portion are arranged linearly in the front-rear direction. The branched portion has a ninth branched portion extending forward or backward from the main portion and having a connection portion with an external wiring at its tip,
The seat sensor according to any one of claims 4 to 7, wherein the connecting portion is arranged behind the second imaginary straight line and forward of the first imaginary straight line. . The seating sensor according to any one of claims 1 to 8, wherein the vehicle seat constitutes a rear seat of an automobile.

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