JP3916475B2 - Crew weight detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an occupant weight detection device that detects an occupant weight based on an output load value from a load sensor provided on a seat body.
[0002]
[Prior art]
Conventionally, for example, in the case where an air bag is provided to protect a seated person of a vehicle seat, in order to determine whether there is a seated person on the target seat, or whether the seated person is, for example, an adult or a child Therefore, an occupant weight detection device is provided on the vehicle seat. As this passenger | crew weight detection apparatus, what is shown by Unexamined-Japanese-Patent No. 11-319552 is known, for example. This detection device has a configuration in which a plurality of load sensors are provided at a plurality of attachment positions of the seat body to the vehicle floor, and the occupant weight is detected based on the output load values of these load sensors.
[0003]
In addition, the detection device includes a displacement regulating mechanism that handles a load exceeding a predetermined range in order to prevent the load sensor from being damaged by an abnormal overload applied to the seat body. Thereby, it is avoided that the load exceeding the predetermined range is directly applied to the load sensor, and the damage is suppressed.
[0004]
[Problems to be solved by the invention]
However, even if such a mechanism for overloading is provided to avoid damage to the load sensor, the load received as a whole of the seat body is not eliminated. It may be deformed. The deformation of the seat main body may cause, for example, a zero point shift of the load sensor, and may reduce the detection accuracy of the occupant weight by the apparatus.
[0005]
On the other hand, when the overall strength or rigidity is increased in order to suppress deformation of the seat body, another problem of increased cost and weight occurs.
Rather, it is preferable to monitor an event (such as an abnormal overload) that may cause a malfunction in the apparatus, detect the malfunction based on this, and prompt the user (driver) for early inspection, for example.
[0006]
The objective of this invention is providing the passenger | crew weight detection apparatus which can detect a malfunction.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the invention according to claim 1 detects a passenger weight by calculating a detected load value based on a plurality of load sensors provided on a seat body and an output load value of the load sensor. In the occupant weight detection device including a controller, the occupant weight detection device includes a calculation unit that calculates a one-side detection load value based on an output load value of a load sensor provided on one side of the seat body, and the calculated one-side detection load value The gist of the invention is that the controller detects a failure when the value falls below a predetermined negative load value.
[0008]
According to a second aspect of the present invention, there is provided an occupant weight detection apparatus including a plurality of load sensors provided on the seat body and a controller that detects a occupant weight by calculating a detected load value based on an output load value of the load sensor. A first calculation means for calculating a one-side detection load value based on an output load value of a load sensor provided on one side of the seat body, and an output load value of a load sensor provided on the other side of the seat body. Second calculated means for calculating the other side detected load value based on the calculated value, the calculated one side detected load value is less than a predetermined negative load value, and the calculated other side detected load value is a predetermined positive value. The gist is that when the load value is exceeded, the controller detects failure.
[0009]
The invention according to claim 3 is the occupant weight detection device according to claim 2, wherein one side and the other side of the seat body are the front side and the rear side, the rear side and the front side, the right side and the left side of the seat body, And at least one of the left side and the right side.
[0010]
The gist of a fourth aspect of the present invention is the occupant weight detection device according to any one of the first to third aspects, wherein the controller drives the notifying means in accordance with the failure detection.
[0011]
(Function)
Generally, when an abnormal overload is applied to the seat body, there may be a problem that the detection accuracy of the occupant weight is reduced by deforming the seat body. It has been confirmed by the present applicant that such a problem is suggested by being unevenly distributed on one side of the seat body and causing a significant negative load. In particular, when a significant negative load is generated unevenly on one side of the seat body and a significant positive load is generated unevenly distributed on the other side of the seat body, for example, an abnormal overload is applied due to a vehicle collision. It is thought.
[0012]
According to the first aspect of the present invention, when the one-side detected load value calculated based on the output load value of the load sensor provided on one side of the seat body is lower than a predetermined negative load value, the controller A defect is detected.
[0013]
According to the second or third aspect of the invention, the one-side detected load value is calculated based on the output load value of the load sensor provided on one side of the seat body. Further, the other side detected load value is calculated based on the output load value of the load sensor provided on the other side of the seat body. When the one-side detected load value falls below a predetermined negative load value and the other-side detected load value exceeds a predetermined positive load value, a malfunction is detected by the controller. In particular, the reliability is improved by detecting a defect based on an unbalanced load generated on one side and the other side of the seat body.
[0014]
According to the fourth aspect of the invention, the early inspection by the user is promoted by driving the notification means in accordance with the defect detection.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a vehicle seat to which an embodiment of the present invention is applied will be described with reference to FIGS.
[0016]
FIG. 1 is a perspective view of a seat body 1 provided in a vehicle seat. The seat body 1 is arranged on the passenger seat side of the vehicle. In FIG. 1, a pair of left and right support frames 2 are fixedly mounted in the front-rear direction (in the direction of the arrow X in FIG. 1) on a vehicle floor (not shown). Yes.
[0017]
A pair of front and rear brackets 3 are fixed to the upper surface of each support frame 2, and a lower rail 4 is supported and fixed along the support frame 2 with respect to the pair of front and rear brackets 3. The pair of left and right lower rails 4 are formed in a U-shaped cross section, and form a slide groove 5 that opens upward and extends in the front-rear direction.
[0018]
A pair of left and right upper rails 6 are arranged in the slide grooves 5 formed in the respective lower rails 4 so as to be slidable in the front-rear direction along the slide grooves 5. As shown in FIG. 2, each upper rail 6 is provided with a lower arm that supports a seat cushion 9 and a seat back 10 of the seat body 1 with a predetermined interval through a pair of left and right front sensor brackets 7 and a rear sensor bracket 8. 16 are connected.
[0019]
As shown in FIG. 3 (a), the front sensor bracket 7 has upper and lower end portions as an upper fastening portion 7a and a lower fastening portion 7b, and the upper and lower fastening portions 7a and 7b are curved to bend the bending portion 7c. Is formed. The front sensor bracket 7 is connected to the lower arm 16 and the front side of the upper rail 6 at the upper and lower fastening portions 7a and 7b, respectively. Then, a front right load sensor 21 and a front left load sensor 22 constituting a load sensor are attached to the bent portions 7c of the right and left front sensor brackets 7, respectively. The front right load sensor 21 and the front left load sensor 22 include a strain detection element such as a strain gauge, for example, and electrically determines the amount of bending of the bending portion 7c relative to the load applied to the seat cushion 9. It comes to detect.
[0020]
As shown in FIG. 3 (b), the rear sensor bracket 8 has upper and lower end portions as an upper fastening portion 8a and a lower fastening portion 8b, and the upper and lower fastening portions 8a and 8b are curved to bend and bend. 8c is formed. The rear sensor bracket 8 is connected to the lower arm 16 and the rear side of the upper rail 6 at the upper and lower fastening portions 8a and 8b, respectively. A rear right load sensor 23 and a rear left load sensor 24 constituting a load sensor are attached to the bent portions 8c of the right and left rear sensor brackets 8, respectively. Similar to the front right load sensor 21 and the front left load sensor 22, the rear right load sensor 23 and the rear left load sensor 24 include a strain detection element such as a strain gauge, and the load applied to the seat cushion 9. In contrast, the amount of bending of the bending portion 8c is electrically detected.
[0021]
FIG. 4 is a block diagram showing an electrical configuration of the occupant weight detection device 20 provided in the vehicle seat. The occupant weight detection device 20 includes the load sensors 21 to 24 and a controller 25.
[0022]
The controller 25 includes a CPU (Central Processing Unit) 26, a filter 27, an output circuit 28, and a communication circuit 30.
The filter 27 receives the load signals from the load sensors 21 to 24 via the amplifier 27a and inputs them to the CPU 26. The CPU 26 calculates output load values FR and FL for the load sensors 21 and 22 based on load signals from the front right load sensor 21 and the front left load sensor 22 that have passed through the amplifier 27a and the filter 27, respectively. It has become. The output load values RR and RL for the load sensors 23 and 24 are calculated in the same manner based on the load signals from the rear right load sensor 23 and the rear left load sensor 24 that have passed through the amplifier 27a and the filter 27. It has become. The detected load value S corresponding to the occupant weight is calculated by summing up these output load values FR to RL. Further, the output load values FR and FL of the front load sensors 21 and 22 are summed, and the front detection load value Fr is summed with the output load values RR and RL of the rear load sensors 23 and 24. The detected load value Rr is calculated respectively. Further, the output load values FR and RR of the right load sensors 21 and 23 are summed, and the right detection load value RH is summed, and the output load values FL and RL of the left load sensors 22 and 24 are summed, thereby detecting the left detection load. Each value LH is calculated.
[0023]
The CPU 26 executes various arithmetic processes according to a control program and initial data stored in advance. For example, the CPU 26 calculates the detected load value S (occupant weight) in the main routine and compares it with a predetermined determination threshold value to determine whether the occupant is an adult or a child. Then, the CPU 26 outputs the calculation result to the communication circuit 30. The operation result of the airbag device is controlled by outputting the calculation result to the airbag controller 33, for example, via the communication circuit 30.
[0024]
The CPU 26 also detects an event that may cause a malfunction in the apparatus in this main routine, that is, an abnormal overload such as a vehicle collision. Then, the CPU 26 outputs the detection result to the output circuit 28. The detection result is output to an indicator lamp 29 as a notification means stored in a combination meter, for example, via the output circuit 28, so that the indicator lamp 29 is turned on, and prompts the user for early inspection. .
[0025]
Next, in the present embodiment, a defect detection mode will be described based on the flowcharts of FIGS. 5 and 6. As described above, this processing is also performed as part of the main routine.
[0026]
When the processing shifts to this routine, first, in step 101, the CPU 26 performs input processing. Specifically, the CPU 26 reads the load signals of the load sensors 21 to 24 filtered by the amplifier 27a and the filter 27, and calculates output load values FR to RL for the load sensors 21 to 24, respectively.
[0027]
Next, in step 102, the CPU 26 determines whether or not the indicator lighting flag registered in the memory is set. This indicator lighting flag is a flag that is set by detecting a defect in the manner described later. Here, if it is determined that the indicator lighting flag is set, the CPU 26 proceeds to step 120 and performs indicator lighting processing. Specifically, the CPU 26 outputs a drive signal to the indicator lamp 29 via the output circuit 28, and turns on the indicator lamp 29. Then, the CPU 26 returns to the main routine as it is.
[0028]
On the other hand, if it is determined in step 102 that the indicator lighting flag is not set (cleared), the CPU 26 proceeds to step 103 and the front detection load value Fr, the rear detection load value Rr, the right detection load value RH, and the left detection. The load value LH is calculated.
[0029]
Next, the CPU 26 proceeds to step 104 to determine whether or not the rear detection load value Rr is below a predetermined excessive minus load value A. The excessive negative load value A is set to a suitable value for detecting, for example, an abnormal negative load on the rear side of the seat body 1 due to a forward collision of the vehicle (a load that cannot be generated in an actual use state). Has been. Here, if it is determined that the rear side detected load value Rr is not less than the excessive negative load value A, the CPU 26 determines that no negative abnormal overload has occurred on the rear side of the seat body 1 in step 107. Migrate to If it is determined that the rear detection load value Rr is less than the excessive minus load value A, the CPU 26 proceeds to step 105.
[0030]
In step 105, the CPU 26 determines whether or not the detected front load value Fr exceeds a predetermined excessive plus load value B. The excessive plus load value B is, for example, an abnormal overload on the positive side that occurs on the front side of the seat body 1 against an abnormal overload on the negative side that occurs on the rear side of the seat body 1 due to a forward collision of the vehicle. Is set to a suitable value for detecting. Here, if it is determined that the front side detected load value Fr does not exceed the excessive plus load value B, the CPU 26 proceeds to step 107 on the assumption that the plus side abnormal overload has not occurred on the front side of the seat body 1. To do. If it is determined that the front detection load value Fr exceeds the excessive plus load value B, the CPU 26 proceeds to step 106 and determines a forward collision.
[0031]
In step 107, the CPU 26 determines whether or not the front detection load value Fr is below a predetermined excessive minus load value C. This excessive negative load value C is set to a suitable value for detecting, for example, an abnormal negative load on the front side of the seat body 1 due to a rearward collision of the vehicle (a load that cannot be generated in the actual use state). ing. Here, if it is determined that the front side detected load value Fr is not less than the excessive minus load value C, the CPU 26 assumes that the minus side abnormal overload has not occurred on the front side of the seat body 1 in FIG. 110. If it is determined that the front detection load value Fr is less than the excessive minus load value C, the CPU 26 proceeds to step 108.
[0032]
In step 108, the CPU 26 determines whether or not the rear detection load value Rr exceeds a predetermined excessive plus load value D. This excessive plus load value D is, for example, an abnormal overload on the positive side that occurs on the rear side of the seat body 1 against an abnormal overload on the negative side that occurs on the front side of the seat body 1 due to a rearward collision of the vehicle. Is set to a suitable value for detecting. Here, if it is determined that the rear side detected load value Rr does not exceed the excessive plus load value D, the CPU 26 assumes that no plus side abnormal overload has occurred on the rear side of the seat body 1 as shown in FIG. The process proceeds to step 110. If it is determined that the rear detection load value Rr exceeds the excessive plus load value D, the CPU 26 proceeds to step 109 and determines a rearward collision.
[0033]
In step 110, the CPU 26 determines whether or not the right detection load value RH is below a predetermined excessive minus load value E. This excessive negative load value E is set to a suitable value for detecting, for example, an abnormal negative load on the right side of the seat body 1 due to a left side collision of the vehicle (a load that cannot be generated in actual use). ing. Here, if it is determined that the right detection load value RH is not less than the excessive minus load value E, the CPU 26 proceeds to step 112 on the assumption that no abnormal negative overload has occurred on the right side of the seat body 1. To do. On the other hand, when it is determined that the right detection load value RH is less than the excessive minus load value E, the CPU 26 proceeds to step 111.
[0034]
In step 111, the CPU 26 determines whether or not the left detection load value LH exceeds a predetermined excessive plus load value F. This excessive plus load value F is, for example, a plus-side abnormal overload generated on the left side of the seat body 1 against a minus-side abnormal overload generated on the right side of the seat body 1 due to a left side collision of the vehicle. It is set to a suitable value for detection. Here, if it is determined that the left detection load value LH does not exceed the excessive plus load value F, the CPU 26 proceeds to step 112 on the assumption that an abnormal plus load on the left side of the seat body 1 has not occurred. To do. If it is determined that the left detection load value LH exceeds the excessive plus load value F, the CPU 26 proceeds to step 114 and determines a side collision.
[0035]
In step 112, the CPU 26 determines whether or not the left detection load value LH is below a predetermined excessive minus load value G. The excessive negative load value G is set to a suitable value for detecting, for example, an abnormal negative load on the left side of the seat body 1 due to a right side collision of the vehicle (a load that cannot be generated in an actual use state). ing. If it is determined that the left detection load value LH is not less than the excessive minus load value G, the CPU 26 determines that no abnormal negative overload has occurred on the left side of the seat body 1 and proceeds directly to the main routine. Return. On the other hand, if it is determined that the left detection load value LH is less than the excessive minus load value G, the CPU 26 proceeds to step 113.
[0036]
In step 113, the CPU 26 determines whether or not the right detection load value RH exceeds a predetermined excessive plus load value H. This excessive plus load value H is, for example, a plus-side abnormal overload generated on the right side of the seat body 1 against a minus-side abnormal overload generated on the left side of the seat body 1 due to a right side collision of the vehicle. It is set to a suitable value for detection. Here, if it is determined that the right detection load value RH does not exceed the excessive plus load value H, the CPU 26 determines that no plus side abnormal overload has occurred on the right side of the seat body 1 and proceeds to the main routine as it is. Return. When it is determined that the right detection load value RH exceeds the excessive plus load value H, the CPU 26 proceeds to step 114 and determines a side collision.
[0037]
The CPU 26 that made the collision determination at any one of Steps 106, 109, and 114 proceeds to Step 115, sets the indicator lighting flag, registers it in the memory, and returns to the main routine. The indicator lighting flag set in accordance with the collision determination is determined in step 102, and the indicator lamp 29 is lit as described above. Therefore, the user (driver) understands the necessity of early inspection by turning on the indicator lamp 29.
[0038]
As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) In the present embodiment, the rear side detection load value Rr is less than the predetermined negative load value A, and the front side detection load value Fr exceeds the predetermined positive load value B, the failure can be detected.
[0039]
(2) In the present embodiment, it is possible to detect a malfunction when the front detection load value Fr is below a predetermined negative load value C and the rear detection load value Rr exceeds a predetermined positive load value D.
[0040]
(3) In the present embodiment, the right detection load value RH is less than the predetermined negative load value E, and the left detection load value LH exceeds the predetermined positive load value F, it is possible to detect a malfunction.
[0041]
(4) In the present embodiment, it is possible to detect a malfunction when the left detection load value LH is lower than the predetermined negative load value G and the right detection load value RH exceeds the predetermined positive load value H.
[0042]
(5) In this embodiment, the reliability can be improved by detecting a defect based on an imbalanced load generated on one side and the other side (front side and rear side, right side and left side) of the seat body 1.
[0043]
(6) In the present embodiment, for example, a seated person cannot occur in a normal use state by detecting a defect based on an unbalanced load on one side and the other side of the seat body 1 indicating characteristics at the time of a vehicle collision. Even if an unnatural load is intentionally applied, erroneous detection of this as a defect can be suppressed.
[0044]
(7) In the present embodiment, the collision direction (front direction, rear direction, side direction) of the vehicle is also determined based on the unbalanced loads on the front side, the rear side, the right side, and the left side of the seat body 1. Therefore, for example, by preliminarily experimentally determining the tendency of occurrence of defects according to the collision direction, inspection and maintenance can be performed smoothly.
[0045]
(8) In the present embodiment, the indicator lamp 29 is turned on when a failure is detected, thereby facilitating early inspection by the user.
(9) In the present embodiment, the indicator lamp 29 is turned on when a defect is detected, so that notification to the user can be smoothly made by visual recognition.
[0046]
In addition, embodiment of this invention is not limited to the said embodiment, You may change as follows.
In the above-described embodiment, the occurrence of the malfunction is notified by turning on the indicator lamp 29 as the notification unit. However, the notification may be performed by, for example, uttering a warning sound by an audio output device. Even if it changes in this way, the effect similar to (1)-(8) of the said embodiment is acquired.
[0047]
In the above-described embodiment, the failure is detected based on an unbalanced load generated on any of the front side, the rear side, the right side, and the left side of the seat body 1. On the other hand, a malfunction may be detected when an unbalanced load occurs on the front side and the rear side of the seat body 1 and on all of the right side and the left side.
[0048]
In the above-described embodiment, the failure is detected based on the unbalanced load generated on one side and the other side (front side and rear side, right side and left side) of the seat body 1. On the other hand, the malfunction may be detected only by an unnatural load generated on one side (front side, rear side, right side, left side) of the seat body 1. Specifically, at least one of the front detection load value Fr, the rear detection load value Rr, the right detection load value RH, and the left detection load value LH is a predetermined negative load value (a negative value that cannot be generated in a normal use state). The failure may be detected by lowering the load on the side.
[0049]
In the embodiment, the output load values FR to RL of the paired load sensors 21 to 24 arranged on one side and the other side of the seat body 1 are summed up to detect the front detection load value Fr and the rear detection load. A value Rr, a right detection load value RH, and a left detection load value LH were calculated. Then, defects were detected based on these detected load values Fr, Rr, RH, and LH. On the other hand, the output load values FR to RL of one load sensor 21 to 24 arranged on one side and the other side of the seat body 1 are replaced with the same detected load values Fr, Rr, RH, and LH as they are. You may make it detect the malfunction of. For example, the same load detection is performed by replacing the output load values FR and RR before and after the right side or the output load values FL and RL before and after the left side with the detected load values Fr and Rr. In this case, a configuration in which one load sensor is disposed before and after the seat body 1 may be employed. Alternatively, the same malfunction detection is performed by replacing the front left and right output load values FR and FL or the rear left and right output load values RR and RL with the detected load values RH and LH. In this case, a configuration in which one load sensor is disposed on each of the left and right sides of the seat body 1 may be employed. Alternatively, similar failure detection is performed based on the output load values FR and RL on the right front side and the left rear side or the output load values FL and RR on the left front side and the right rear side. Incidentally, such a load imbalance occurring in the diagonal direction is caused by, for example, an offset collision (an oblique collision) of the vehicle.
[0050]
In the embodiment, a pair of left and right front right load sensors 21 and 22 is provided at the front of the seat body 1, and a pair of left and right rear right load sensors 23 and 24 are provided at the rear of the seat body 1. . The number of sensors (four) and their arrangement are examples, and other numbers and arrangements may be adopted. The point is that a plurality of load sensors are arranged at a predetermined position of the seat body 1 and a defect is detected according to the detected load value based on the output load value of the load sensor.
[0051]
The shape of the front and rear sensor brackets 7 and 8 employed in the above embodiment is an example, and the shape is arbitrary as long as bending occurs according to the seat weight (sitting load).
[0052]
The mounting positions (front and rear sensor brackets 7 and 8) of the load sensors 21 to 24 employed in the above embodiment are merely examples, and the mounting positions are arbitrary as long as the seat weight (sitting load) is detected. It is.
[0053]
Next, technical ideas other than the claims that can be grasped from the above embodiments will be described together with the effects thereof.
(A) The occupant weight detection device according to claim 4, wherein the notification means is an indicator lamp. According to this configuration, the indicator lamp is driven (lighted) in accordance with the failure detection, so that the notification to the user can be smoothly made by visual recognition.
[0054]
【The invention's effect】
As described above in detail, according to the invention according to any one of claims 1 to 3, it is possible to provide an occupant weight detection device capable of detecting a malfunction.
[0055]
According to the fourth aspect of the present invention, the early inspection by the user can be promoted by driving the notification means in accordance with the defect detection.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a vehicle seat according to the present invention.
FIG. 2 is a side view showing the embodiment.
FIG. 3 is a front view showing front and rear sensor brackets.
FIG. 4 is a block diagram showing an electrical configuration of the embodiment.
FIG. 5 is a flowchart showing a defect detection mode of the embodiment.
FIG. 6 is a flowchart showing a defect detection mode of the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Seat body 20 Occupant weight detection device 21 Front right load sensor 22 constituting load sensor Front left load sensor 23 constituting load sensor Rear right load sensor 24 constituting load sensor Rear left load sensor 25 constituting load sensor Controller

Claims (4)

In an occupant weight detection device comprising a plurality of load sensors provided in the seat body and a controller that detects a occupant weight by calculating a detected load value based on an output load value of the load sensor,
A calculating means for calculating a one-side detected load value based on an output load value of a load sensor provided on one side of the seat body;
The occupant weight detection device according to claim 1, wherein when the calculated one-side detected load value falls below a predetermined negative load value, the controller detects a failure. In an occupant weight detection device comprising a plurality of load sensors provided in the seat body and a controller that detects a occupant weight by calculating a detected load value based on an output load value of the load sensor,
First calculation means for calculating a one-side detection load value based on an output load value of a load sensor provided on one side of the seat body;
Second calculation means for calculating the other side detection load value based on the output load value of the load sensor provided on the other side of the seat body,
When the calculated one-side detected load value falls below a predetermined negative load value and the calculated other-side detected load value exceeds a predetermined positive load value, the controller detects a failure. An occupant weight detection device. The one side and the other side of the seat main body are at least one of a front side and a rear side, a rear side and a front side, a right side and a left side, and a left side and a right side of the seat main body. Crew weight detection device. In the passenger | crew weight detection apparatus in any one of Claims 1-3,
The said controller drives an alerting | reporting means with malfunction detection, The passenger | crew weight detection apparatus characterized by the above-mentioned.

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