JP4543520B2 - Crew discrimination system for automobile and method for manufacturing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an occupant discrimination system for an automobile that incorporates a sensor inside an automobile seat (lower seat) and detects the presence or absence of an occupant on the seat and the presence or absence of a child-specific seat from the sensor output.
[0002]
[Prior art]
Conventionally, wearing a seat belt has been obligatory as a safety measure for protecting passengers from the impact of a vehicle accident. Therefore, when the seat belt is not worn, a warning light is turned on or a buzzer is sounded to warn the occupant of wearing the seat belt.
In recent years, the number of vehicles equipped with airbags has increased rapidly. For example, in a vehicle with airbags attached to the passenger seat, the passenger seat can be used in the event of an accident even though no passenger is seated in the passenger seat. Will open the airbag. Therefore, a technology has been put into practical use so that the passenger seat airbag is not opened when no passenger is seated in the passenger seat.
In order to warn the user of wearing the seat belt and prevent the passenger seat airbag from being opened, it is necessary to detect in advance that the occupant is sitting or not sitting on the seat. As a method for detecting the presence or absence of this occupant, an occupant detection system in which a pressure sensitive sensor is incorporated in the seat is known.
[0003]
[Problems to be solved by the invention]
The following dangers have been pointed out because the airbag installed as a safety device has a large inflation force when opened.
For example, in a vehicle equipped with an airbag in the passenger seat, when a child sits in the passenger seat, the inflation force of the airbag becomes an impact force, which may have an unexpected adverse effect on the child. For this reason, for example, when the passenger in the passenger seat is a child, it is better not to operate the airbag in the passenger seat or to control the inflation force of the airbag so as to reduce the impact.
Here, as a means for determining whether the passenger in the passenger seat is a child or an adult, it is conceivable to use the above-described passenger detection system. That is, if the load detected by the pressure sensor incorporated in the seat is greater than a predetermined value, it can be determined that the child is an adult, and if the load is smaller than the predetermined value, the child can be determined.
[0004]
However, when determining whether a child or an adult is only based on the magnitude of the load detected by the pressure sensor, there are the following problems.
First, even if the occupant is an adult, when the occupant rests his back on the seat back (backrest), the load detected by the pressure sensor becomes smaller as the seat back is tilted down. End up.
Second, when a child-specific seat (baby seat, child seat, junior seat, etc.) is used in the passenger seat, the weight of the child-specific seat is added to the weight of the child, so the load increases.
Third, when a child-specific seat is used, the child-specific seat is fixed to the passenger seat with a seat belt, so that the load detected by the pressure sensor changes depending on the tightening force of the seat belt.
As a result, with the conventional occupant detection system, it is extremely difficult to accurately determine whether a child or an adult.
[0005]
Therefore, the present applicant has developed an occupant discrimination system that can accurately discriminate whether a child or an adult regardless of the presence or absence of a child-specific seat.
This occupant discrimination system incorporates a sensor mat in which a plurality of sensor cells are arranged on a plane into the interior of the seat (under the seating surface), and determines the occupant's weight based on the sum of loads detected from the output values of the individual sensor cells and the load distribution. This is to make a determination. For example, regardless of adults and children, the load distribution detected from the output value of each sensor cell differs greatly between when a person is sitting directly on the seat and when using a child-specific seat. Based on the load distribution, it is possible to detect the presence or absence of a child-specific seat. Even if a child-specific seat is not used, it is not possible to determine whether a child or an adult is based only on the sum of the loads detected by individual sensor cells. Or adult.
[0006]
By the way, the sheet | seat incorporating a sensor mat has covered the surface of the sheet | seat foam which forms a base part (base) with the sheet | seat skin. The sheet skin is applied with tension in order to eliminate slack in appearance. At this time, the tension of the seat skin is applied or biased relative to the seat foam, a large stress is generated in part of the sheet form, the output of the sensor cell becomes unstable in its effects. As a result, an erroneous determination may occur during occupant determination.
The present invention has been made based on the above circumstances, and its purpose is to determine whether or not the output of each sensor cell is affected by the stress generated in the sheet foam as the sheet skin is attached. An object of the present invention is to provide an occupant discrimination system for an automobile and a manufacturing method thereof .
[0007]
[Means for Solving the Problems]
(Means of Claim 1)
This onset Ming, comprises a sensor-equipped seat incorporating a sensor mat can detect pressure plurality of sensor cells are arranged on a plane individual sensor cells independently therein, the sensor-equipped sheets from the output of the individual sensor cells An occupant discrimination system for discriminating an occupant above, wherein a sensor built-in seat has a sensor mat placed on an upper surface of a sheet foam forming a base portion of the seat, and a sheet skin is attached to the sheet foam covering the sensor mat. was followed, selected as previously determined cell specific sensor cells from the sensor mat, the output of each sensor cell based on the output value of the judgment cells performed stably whether the determined sensor output determining step and, when the output value of the judgment cells than preset determination value, the output of the sensor cell is determined not to be stable, the sheet table After the break work to eliminate stress caused in the sheet form by sticking, again, characterized in that it is produced by carrying out the sensor output determination process.
According to the present invention, when a large stress is generated in the sheet form due to the sheet covering, it can be determined whether or not the output of each sensor cell is affected by the stress. Further, it is possible to determine whether or not the output of each sensor cell is stable only by selecting a determination cell on behalf of the individual sensor cell and monitoring the output value of the determination cell.
In addition, if it is determined that the sensor output is not stable, the sensor output determination process will be performed again after performing a break-in operation to remove the stress generated in the sheet form by attaching the sheet cover. The effect of stress generated in the sensor is removed, and a stable sensor output can be obtained.
The “break-in operation” is a process of applying an external force or the like to the sheet foam from the surface of the sheet skin, for example, to disperse the initial tension of the sheet skin (eliminate the bias of the tension), or to correct the positional deviation of the sheet skin. It is.
[0010]
(Means of Claim 2 )
In the passenger | crew discrimination | determination system for motor vehicles described in Claim 1 ,
The sensor mat is characterized in that a determination cell is provided in a portion where a large stress is generated in the sheet foam as the sheet skin is attached in a state where the sensor mat is incorporated in the sheet.
In this case, the determination cell is most affected by the stress generated in the sheet form as compared with other sensor cells. Therefore, by comparing the output value of the determination cell with the determination value, It is possible to effectively determine whether or not the output is stable.
[0011]
(Means of claim 3)
In the vehicle occupant discrimination system according to claim 1 or 2,
The sensor mat is provided with a dummy sensor separately from the individual sensor cells used for occupant discrimination, and the dummy sensor is used as a determination cell.
That is, if a sensor cell that can be used as a determination cell is not provided in the sensor mat at a site that is most affected by the stress generated in the sheet form, a dummy sensor that is used only in the sensor output determination process may be provided. Needless to say, the dummy sensor can detect a load at the same level as each sensor cell.
(Means of claim 4)
The present invention includes a sensor mat in which a plurality of sensor cells are arranged on a plane so that each sensor cell can independently detect pressure, and the sensor mat is incorporated in a seat of an automobile, from the output of each sensor cell. A method for manufacturing an occupant discrimination system for discriminating an occupant on a seat, wherein the sensor mat is arranged on an upper surface of a sheet form forming a base portion of the seat in a seat manufacturing process in which the sensor mat is incorporated, After covering and attaching the sheet skin to the sheet form, a specific sensor cell is selected from the sensor mat in advance as a determination cell, and whether or not the output of each sensor cell is stable based on the output value of this determination cell When the sensor output determination step is performed and the output value of the determination cell is equal to or greater than a predetermined determination value, the sensor It determines that the output of the LE is not stable, after break work to eliminate stress caused in the sheet form by sticking the seat skin, again, which comprises carrying out the sensor output determination process.
(Means of claim 5)
5. The method for manufacturing an automobile occupant discrimination system according to claim 4, wherein the sensor mat is incorporated in the seat, and the judgment cell is provided at a portion where a large stress is generated on the seat foam as the seat cover is attached. It is characterized by comprising.
(Means of claim 6)
6. The method of manufacturing an occupant discrimination system for an automobile according to claim 4 or 5, wherein the sensor mat includes a dummy sensor separately from each sensor cell used for occupant discrimination, and the dummy sensor is used as a determination cell. It is characterized by doing.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of an occupant discrimination system for an automobile will be described with reference to the drawings.
First, the structure and manufacturing process of the sensor built-in seat 1 used in the vehicle occupant discrimination system will be described.
The sensor built-in seat 1 of the present embodiment is a seat cushion that receives an occupant's buttocks, and as shown in FIG. 3, a base 3 supported by a slide rail 2 and a seat foam (hereinafter referred to as a foam) installed on the base 3. 4) and a sheet skin 5 covering the surface of the foam 4, and a sensor mat 6 (see FIG. 2) is incorporated between the foam 4 and the sheet skin 5.
[0013]
The foam 4 forms a base portion (base) of the sheet 1, and a suspension groove 7 (see FIG. 2) for narrowing the sheet skin 5 is provided on the upper surface thereof.
The sheet skin 5 is squeezed into the foam 4 along the suspension groove 7, and the squeezed portion (trench portion) is formed as a design on the appearance. On the back surface of the sheet skin 5, an ear hook 8 (see FIG. 6) for narrowing the sheet skin 5 into the hanging groove 7 of the foam 4 is provided in a bag shape.
In the following description, with respect to the foam 4, the part surrounded by the two hanging grooves 7 is called the center part, and the part outside the hanging groove 7 is called the side part. The part surrounded by is called the center part, and the part outside the earlobe part 8 is called a horizontal trim.
[0014]
As shown in FIG. 2A, the sensor mat 6 has a first sensor portion 6A disposed at the center portion of the foam 4 and a second sensor portion 6B disposed at a side portion of the foam 4. A plurality of sensor cells 9 are respectively arranged.
The sensor cell 9 is a pressure conversion element whose resistance value changes according to pressure, for example, and a plurality of sensor cells 9 arranged on the sensor mat 6 can detect pressure independently.
The sensor mat 6 is connected to the ECU 11 via the printed circuit board 10, converts a change in pressure detected by each sensor cell 9 into an electrical signal, and outputs the electrical signal to the ECU 11.
[0015]
The ECU 11 is an electronic control unit with a built-in microcomputer, and is incorporated in the center of the rear end of the foam 4 as shown in FIG. 2B, for example.
The ECU 11 detects the sum of the loads applied to the seat and the load distribution from the output signals of the individual sensor cells 9, and based on the detection results, the presence / absence of a passenger, the presence / absence of a child-dedicated seat, and the child And adult discrimination.
[0016]
a) The presence / absence of an occupant is obtained by calculating the sum of the loads detected by the individual sensor cells 9, and if the value is equal to or greater than a predetermined value, it is determined that the occupant is seated on the seat 1, and if smaller than the predetermined value, the seat 1 It is determined that no occupant is sitting.
b) The presence / absence of a child-specific seat is determined by detecting the load distribution on the seat from the output signals of the individual sensor cells 9 and determining whether the child-specific seat is used according to the shape pattern estimated from the load distribution.
c) In order to discriminate between children and adults, a decision criterion based on the load distribution is added to a decision criterion based on the sum of loads, and a decision is finally made as to whether the child is an adult.
[0017]
Next, the manufacturing process of the sensor built-in sheet 1 will be described.
FIG. 5 is a flowchart showing the manufacturing process.
Step10 ... Install Form 4 on stand 3.
Step 20 ... The sensor mat 6 is arranged at a predetermined position on the upper surface of the form 4. Here, by temporarily fixing the sensor mat 6 to the foam 4, it is possible to prevent the sensor mat 6 from being displaced when the next sheet skin 5 is attached.
Step30 ... Attach the sheet skin 5
[0018]
The sheet skin 5 is generally attached by the following procedure.
First step: First, as shown in FIG. 6 (a), the central portion of the sheet skin 5 is arranged in alignment with the central portion of the foam 4, and the wire 12 passed through the earlobe 8 and the foam 4 By simultaneously hooking the wire 13 provided on the wire 13 with a C-shaped hog ring 14 and closing and tightening the hog ring 14, the central portion of the sheet skin 5 is attached so as to cover the central portion of the foam 4.
[0019]
Second step: Subsequently, the lateral trim is turned to the side surface of the foam 4 so as to wrap the outside of the side portion of the foam 4, and the hook portion 5a provided at the end of the lateral trim is hooked on the outer edge portion of the base 3 or the like. Do work. At this time, in order to prevent looseness (wrinkle) from occurring in the lateral trim, tension is applied to the lateral trim in the assembled state. That is, as shown in FIG. 6B, the assembly work of the horizontal trim is performed in a state where the foam 4 is pressed and crushed in the vertical direction, and the hook portion 5a of the horizontal trim is attached to the outer edge portion of the base 3 or the like. After hooking, the pressure from the up and down direction is removed. As a result, the lateral trim is attached so as to cover from the side portion of the foam 4 to the side surface of the foam 4 in a state where tension is applied (a state where there is no slack).
[0020]
Step40 ... A sensor output determination step is performed.
This sensor output determination step determines whether or not the output of each sensor cell 9 provided in the sensor mat 6 is stable. A specific sensor cell 9 is selected in advance as the determination cell 9a, and the determination cell is selected. The output value of 9a is compared with the determination value (see FIG. 7).
The determination cell 9a is arranged in a portion where a large stress is generated on the foam 4 due to the sheet skin 5 being attached (for example, in the vicinity of the four corners of the foam 4 and the trench portion) in a state where the sensor mat 6 is incorporated in the sheet. Sensor cell 9 is used.
[0021]
In addition, when the sensor mat 6 does not have the sensor cell 9 in a portion where a large stress is generated on the foam 4, a dummy used only in this sensor output determination step, separately from the sensor cell 9 used for normal occupant determination. A sensor may be provided as the determination cell 9a (see FIG. 2). However, it goes without saying that the dummy sensor can detect the same level of load as the other sensor cells 9.
[0022]
Next, the determination method will be described.
a) The output value of the determination cell 9a is compared with the determination value. When the output value of the determination cell 9a is larger than the determination value, it is determined that the output of each sensor cell 9 is not stable. In this case, as shown in FIG. 1 (a), stress is generated in the foam 4 due to the tension of the sheet skin 5, and the foam 4 is greatly deformed at a portion where the stress is large. Output value is larger than the determination value (see FIG. 7).
[0023]
Therefore, when the output value of the determination cell 9a is larger than the determination value, after performing a break-in operation for removing the stress generated in the form 4, the sensor output determination step is performed again. In the “break-in operation”, for example, an external force or the like is applied to the foam 4 from the surface of the sheet skin 5 to disperse the initial tension of the sheet skin 5 (eliminate the bias of the tension), or the positional deviation of the sheet skin 5 or the like. It is a process to correct.
When the stress of the form 4 is removed by this “break-in operation”, the deformation of the form 4 is inevitably reduced as shown in FIG. 1B, and accordingly, the output value of the determination cell 9a is also reduced. (See FIG. 7).
b) When the output value of the determination cell 9a is smaller than the determination value, it is determined that the output of each sensor cell 9 is stable.
[0024]
(Effect of this embodiment)
The above-described sensor-incorporated sheet 1 can determine whether or not the output of each sensor cell 9 is stable by performing a sensor output determination step after the sheet skin 5 is attached. As a result, it is possible to prevent erroneous determination of occupant determination due to use of the sensor output in an unstable state.
Further, in the sensor output determination step, the output value of the determination cell 9a arranged in the vicinity of a part where a large stress occurs in the form 4 is compared with the determination value. Since this determination cell 9a is most affected by the stress generated in the foam 4 as compared with the other sensor cells 9, the individual sensor cells 9 can be compared with the case where the other sensor cells 9 are used as the determination cells 9a. Whether or not the output is stable can be determined effectively and more reliably.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a sheet (AA cross-sectional view of FIG. 4).
FIG. 2 is a plan view (a) and a side view (b) of a foam having a sensor mat.
FIG. 3 is an exploded perspective view of a sheet.
FIG. 4 is a perspective view of a seat.
FIG. 5 is a flowchart showing a sheet manufacturing process.
FIG. 6 is a process diagram for assembling a sheet skin.
FIG. 7 is a graph showing changes in the output value of the determination cell after the sheet skin is pasted and after the foam stress is removed.
[Explanation of symbols]
1 Sensor built-in sheet (sheet)
4 Form (sheet form)
5 Sheet skin 6 Sensor mat 9 Sensor cell 9a Determination cell

Claims (6)

A plurality of sensor cells are arranged on a plane, and each of the sensor cells has a sensor built-in seat in which a sensor mat capable of independently detecting pressure is incorporated, and an occupant on the sensor built-in seat is output from the output of the individual sensor cells. An occupant discrimination system for discriminating
The sensor built-in sheet is
The sensor mat is arranged on the upper surface of the sheet foam forming the base portion of the sheet, and after covering the sensor mat and attaching a sheet skin to the sheet foam, a specific sensor cell is used as a determination cell in advance from the sensor mat. selected, the output of the individual sensor cells based on the output value of the judgment cells is performed stably whether the determined sensor output determination process, the output value of the judgment cells are set in advance and when the above determination value, after the output of the sensor cell is determined not to be stable and perform a test operation for removing the stresses generated in the seat foam by sticking of the seat skin, again, the sensor An automobile occupant discrimination system manufactured by performing an output judgment step. In the passenger | crew discrimination | determination system for motor vehicles described in Claim 1,
The sensor mat includes the determination cell in a portion where a large stress is generated in the sheet foam when the sheet cover is attached in a state where the sensor mat is incorporated in the seat. Passenger identification system. In the vehicle occupant discrimination system according to claim 1 or 2,
In addition to the individual sensor cells used for occupant discrimination, the sensor mat includes a dummy sensor, and the dummy sensor is used as the determination cell. A plurality of sensor cells are arranged on a plane, and each sensor cell has a sensor mat that can detect pressure independently.
This sensor mat is incorporated in a seat of an automobile, and is a method for manufacturing an occupant discrimination system for discriminating an occupant on the seat from the output of each sensor cell,
In the manufacturing process of the sheet incorporating the sensor mat,
The sensor mat is arranged on the upper surface of the sheet foam forming the base portion of the sheet, and after covering the sensor mat and attaching a sheet skin to the sheet foam, a specific sensor cell is previously used as a determination cell from the sensor mat. A sensor output determination step is performed to determine whether or not the output of each individual sensor cell is stable based on the output value of the determination cell, and the output value of the determination cell is preset. When the determination value is equal to or greater than the determination value, it is determined that the output of the sensor cell is not stable. The manufacturing method of the passenger | crew discrimination | determination system for motor vehicles characterized by implementing a process. In the manufacturing method of the passenger | crew discrimination | determination system for motor vehicles described in Claim 4,
The sensor mat includes the determination cell in a portion where a large stress is generated in the sheet foam when the sheet cover is attached in a state where the sensor mat is incorporated in the seat. Method for occupant discrimination system. In the manufacturing method of the passenger | crew discrimination | determination system for motor vehicles described in Claim 4 or 5,
The sensor mat includes a dummy sensor separately from the individual sensor cells used for occupant discrimination, and the dummy sensor is used as the determination cell.

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