JPH11301321A - Occupant detecting device for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an occupant seated on a seat as well as to reduce manufacturing costs. SOLUTION: A joint 50 having the rear end supported by shaft 46 so as to be oscillated is arranged on a connecting part between the tip of a motor shaft 44A of a lifter motor 44 for constituting a lifter mechanism of a seat and a rear lifter rod. The front end 50A of the joint 50 is connected to the tip of the motor shaft 44A through a case 59 fixed to the tip of the motor shaft 44A, and the joint 50 can be moved in the case, in such a direction as to brought in contact with and separated from the motor shaft 44A. A load switch 54 is arranged on the front end 50A of the joint 50, and the load switch 54 is turned on when load having a specified value or more acts on the motor shaft 44A through the joint 50.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant detection device for a seat, and more particularly to a occupant detection device for a seat provided on a seat of an automobile.

[0002]

2. Description of the Related Art Conventionally, as an example of a seat occupant detection device disposed on a seat of an automobile, Japanese Patent Application Laid-Open No.
A structure disclosed in Japanese Patent Application Laid-Open No. 829 is known.

As shown in FIG. 10, in this device, a flat portion 100 of a seat cushion frame 100 made of resin is used.
A, a sheet-shaped conductive layer 102 is attached, and the conductive layer 102 is pressed by the buttocks of the occupant sitting on the seat cushion, and the capacitance of the conductive layer 102 changes, so that there is no occupant on the seat cushion. Is determined.

[0004]

However, in this device, the flat portion 10 of the seat cushion frame 100 is not provided.
In each case, the sheet-shaped conductive layer 10
It was necessary to change the shape of No. 2 and there was a problem that the manufacturing cost was increased.

The present invention has been made in view of the above circumstances, and has as its object to provide a seat occupant detection device capable of reducing the manufacturing cost and detecting an occupant sitting on a seat.

[0006]

According to the present invention, there is provided a seat occupant detection apparatus applied to a seat having a lift mechanism for moving a seat cushion up and down,
An occupant detecting means for detecting at least one of the presence or absence and the weight of the occupant seated on the seat cushion based on the input load acting on the lift mechanism is provided.

Accordingly, the occupant detection means detects at least one of the presence or absence of the occupant seated on the seat cushion and the weight based on the input load acting on the lift mechanism. Further, in order to detect at least one of the presence or absence of the occupant seated on the seat cushion and the weight based on the input load acting on the lift mechanism, if a predetermined lift mechanism is provided, the occupant detection means is changed for each seat. No need. As a result, manufacturing costs can be reduced.

According to a second aspect of the present invention, in the seat occupant detection device according to the first aspect, the occupant detection means includes:
The lift mechanism has a load detecting means for detecting a pressing force acting on an output shaft of a lifter motor.

Therefore, when the occupant is seated, the input load acting on the lift mechanism is input to the load detection means via the output shaft of the lifter motor. Based on this pressing force, the occupant detection means detects at least one of the presence or absence of the occupant seated on the seat cushion and the weight. Also,
In order to detect at least one of the presence or absence of the occupant seated on the seat cushion and the weight based on the input load acting on the output shaft of the lifter motor, if a predetermined lift mechanism is provided, the occupant detection means is provided for each seat. No need to change. As a result, manufacturing costs can be reduced.
According to a third aspect of the present invention, in the seat occupant detection device according to the first aspect, the occupant detection means includes a current value detection means for detecting a starting current value of a lifter motor of the lift mechanism. And

Therefore, when the starting current value fluctuates due to the presence or absence of the occupant and the weight when the lifter motor is started, the output of the current value detecting means fluctuates. Based on the output of the current value detecting means, the occupant detecting means detects at least one of the presence or absence of the occupant seated on the seat cushion and the weight. Further, in order to detect at least one of the presence or absence of the occupant seated on the seat cushion and the weight based on the starting current value of the motor for the lifter, if a predetermined lift mechanism is provided, the occupant detection means is changed for each seat. No need. As a result, manufacturing costs can be reduced. According to a fourth aspect of the present invention, in the seat occupant detection device according to any one of the first to third aspects, the occupant detection unit corrects a detection value based on a swing angle of a lift mechanism. It is characterized by having.

Therefore, in addition to the contents described in any one of claims 1 to 3, the occupant seated on the seat cushion can correct the detection value of the occupant detection means based on the swing angle of the lift mechanism by the correction means. At least one of the presence or absence and the body weight can be accurately detected.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a seat load detecting device according to the present invention will be described with reference to FIGS.

In the drawings, an arrow FR indicates a forward direction of the vehicle, and an arrow UP indicates an upward direction of the vehicle.

As shown in FIG. 3, a seat 12 is mounted on a floor 10 of the vehicle. The seat 12 includes a seat cushion 16 on which an occupant sits and a seat back 18 for supporting the back of the occupant.

A pair of left and right seat slide rails 20 are arranged on the seat 12 along the longitudinal direction of the vehicle.
Both front and rear ends of the seat slide lower rail 22 of each seat slide rail 20 are fixed to the floor 10 by fixing members (not shown) such as bolts. A seat slide upper rail 24 is set on each of the seat slide lower rails 22 so as to be slidable in the vehicle front-rear direction. Left and right seat cushion side frames 34 are fixed to these seat slide upper rails 24, respectively. ing. Therefore, sheet 1
Numeral 2 is movable in the vehicle front-rear direction integrally with the seat slide upper rail 24 with respect to the seat slide lower rail 22.

As shown in FIG. 1, a vertical wall portion 2 erected near the front ends of the left and right seat slide upper rails 24.
A front lifter rod 26 is rotatably mounted on 4A. The front end of the front vertical link 30 is connected to both ends of the front lifter rod 26, and the rear end of the front vertical link 30 swings around the front end 34A of the seat cushion side frame 34 by the shaft 36. It is supported as much as possible.

As shown in FIG. 3, the left and right seat slide upper rails 24 have vertical wall portions 2 erected near the rear ends thereof.
A rear lifter rod 38 is rotatably mounted on 4B. At both ends of the rear lifter rod 38,
A front end of the rear lifter link 40 is fixed, and a rear end of the rear lifter link 40 is pivotally supported by a shaft 36 on a rear end 34 </ b> B of the seat cushion side frame 34.

The front lifter rod 26 and the rear lifter rod 38 are connected to each other by a connecting rod 43. The load input to the front lifter rod 26 is transmitted to the rear lifter rod 38 and the rear lifter rod 38 The input load is transmitted to the front lifter rod 26.

The rear lifter rod 38 has a downwardly projecting portion 38A, and a lower end of the projecting portion 38A has a motor shaft 44A of a lifter motor 44.
Are pivotally connected by a shaft 46. The lifter motor 44 is fixed to the seat slide upper rail 24 via a brat 48.

Therefore, when the motor shaft 44A of the lifter motor 44 moves rearward (in the direction of arrow X in FIG. 4), the rear lifter rod 38 and the rear lifter link 4
0 rotates in the counterclockwise direction of FIG. 4 (the direction of arrow Y in FIG. 4), and the front lifter rod 26 and the front vertical link 30 swing in the direction opposite to the direction of arrow B in FIG. Then, the seat cushion side frame 34 is raised from the position indicated by the two-dot chain line in FIG. 4 to the position indicated by the upper solid line. When the motor shaft 44A of the lifter motor 44 moves forward (in the direction opposite to the arrow X in FIG. 4), the rear lifter rod 3
1 and the rear lifter link 40 rotate in the clockwise direction in FIG. 4 (the direction opposite to the arrow Y in FIG. 4), and the front lifter rod 26 and the front vertical link 30 are connected via the connecting rod 43 to the arrow B in FIG.
Swinging in the direction
From the position shown by the solid line in FIG. 4 to the position shown by the two-dot chain line.

As shown in FIG.
At the connection between the tip of A and the rear lifter rod 38,
A joint 50 whose rear end is swingably supported by a shaft 46 is provided. Front end 50 of joint 50
A is connected to the distal end of the motor shaft 44A via a case 52 fixed to the distal end of the motor shaft 44A. (Arrow Z direction). At the front end 50A of the joint 50, a load switch 54 is provided as load detection means of the occupant detection means. Therefore, when a load equal to or more than a predetermined value acts on the motor shaft 44A via the joint 50, the load switch 54 is turned on. The load switch 54 is connected to an occupant detection circuit 56 as occupant detection means including a microcomputer.
6 is a seat 12 based on the on / off state of the load switch 54.
It is determined whether or not an occupant is seated above.

The occupant detection circuit 56 is connected to a known airbag device activation circuit or the like. For example, in the airbag device activation circuit, a plurality of data including a signal from the occupant detection circuit 56 are used. Activation of the airbag device,
Inactivity is to be determined.

Next, the operation of the present embodiment will be described.

In this embodiment, as shown in FIG. 5, when the occupant sits on the seat 12, the load acting on the rear of the seat cushion side frame 34 (arrow F1 in FIG. 5).
As a result, the shaft 42 is attached to the seat cushion side frame 34.
The load (arrow F2 in FIG. 5) acts on the rear lifter link 40 connected by the
8 rotates clockwise in FIG. 5 (the direction of arrow A in FIG. 5).

At the same time, as shown in FIG. 1, a load acting in front of the seat cushion side frame 34 (FIG. 1)
Arrow F3) is transmitted to the front lifter rod 26 via the front vertical link 30, and the front lifter rod 26 is rotated clockwise in FIG. 1 (arrow B in FIG. 1).
Direction). As a result, the connecting rod 4
3 moves forward (in the direction of arrow C in FIG. 5), and the rear lifter rod 38 rotates in the direction of arrow A in FIG.

As a result, the motor shaft 44 connected to the projection 38A of the rear lifter rod 38 by the shaft 46
A is applied with a pressing force along the axial direction (arrow F3 in FIG. 5). When the pressing force is equal to or more than the predetermined value, the load switch 54 is turned on, and the occupant detection circuit 56 determines that the occupant is seated on the seat 12 from the on state of the load switch 54.

Therefore, in this embodiment, if a predetermined lift mechanism is provided, it is not necessary to change and arrange the occupant detection means for each seat unlike the conventional structure shown in FIG. Can be reduced.

Next, a second embodiment of the seat occupant detection device according to the present invention will be described with reference to FIGS.

The same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in FIG. 6, in this embodiment, the lifter motor 44 is connected to a current detection circuit 60 as current value detection means of the occupant detection means, and the current detection circuit 60 is connected to the lifter motor 44. Is detected. The current detection circuit 60 is connected to an occupant detection circuit 56 as occupant detection means,
The occupant detection circuit 56 determines whether or not the occupant is seated on the seat 12 based on the current detected by the current detection circuit 60.

Next, the operation of the present embodiment will be described.

In this embodiment, when the occupant sits on the seat 12, the load applied to the rear of the seat cushion side frame 34 (arrow F1 in FIG. 6) lowers the seat cushion side frame 34. As a result, a load is applied to the rear lifter link 40 connected to the seat cushion side frame 34 by the shaft 42 (arrow F2 in FIG. 6).
, The rear lifter rod 38 rotates in the direction of arrow A in FIG.

Similarly, the load (arrow F3 in FIG. 6) acting on the front of the seat cushion side frame 34 is transmitted to the front lifter rod 26 via the front vertical link 30, and the front lifter rod 26 is moved by the arrow in FIG. Rotate in the B direction. As a result, the connecting rod 43 moves in the direction of arrow C in FIG. 6, and the rear lifter rod 38 rotates in the direction of arrow A in FIG.

Therefore, the convex portion 3 of the rear lifter rod 38
Motor shaft 44A connected to shaft 8A by shaft 46
, A pressing force along the axial direction (arrow F3 in FIG. 6) acts. Therefore, the lifter motor 44 is operated,
When raising the sheet, it is necessary to raise the sheet against this pressing force, so as shown in FIG.
The starting current value A1 of the lifter motor 44 is larger than the starting current value A2 when the occupant is not sitting on the seat 12. The time T1 in FIG.
4 shows the rotation start time.

The starting current value is detected by the current detecting circuit 60, and the occupant detecting circuit 56 determines whether or not the occupant is seated on the seat 12 based on the starting current value detected by the current detecting circuit 60. judge. That is, when the starting current value is equal to or larger than the predetermined value, it is determined that the occupant is seated on the seat 12.

Therefore, in this embodiment, if a predetermined lift mechanism is provided, it is not necessary to change and arrange the occupant detection means for each seat unlike the conventional structure shown in FIG. Can be reduced.

In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to such an embodiment, and various other embodiments are included within the scope of the present invention. It is clear to a person skilled in the art that is possible. For example, in the first embodiment, the load switch 54 is used. However, instead of the load switch 54, as shown in FIG.
4 and a load estimating circuit 66 as occupant detection means is used in place of the occupant detection circuit 56,
The configuration may be such that the weight of the occupant is estimated based on the output value of No. 4. In this case, the estimated weight = proportional constant × shaft load, so that the load on the motor shaft 44A is
, And the load transmitted to the motor shaft 44A changes depending on the horizontal angle θ of the rear lifter link 40. For this reason, it is preferable to increase the distance L from the rotation center of the rear lifter rod 38 in the rear lifter link 40 to the mounting point of the shaft 42. Alternatively, as shown in FIG. 9, a goniometer 62 as a correcting means for detecting the angle of the rear lifter link 40 is provided, and this goniometer 62 is connected to a load estimating circuit 66, and a load switch is provided in the case 52. It is preferable to correct the output of the load cell 64 disposed in place of the above.

In the second embodiment, the occupant detection circuit 5
When the starting current value detected by the current detection circuit 60 is equal to or larger than the predetermined value, it is determined that the occupant is seated on the seat 12. The weight of the occupant may be estimated based on the starting current value detected by the circuit 60.

The present invention is not limited to the lifter mechanism in which the entire seat moves up and down as in the above embodiments, but also includes only the seat cushion in which the seat back is fixed to the upper rail and attached to the seat cushion side frame, or the seat cushion. It is also applicable to a so-called vertical adjuster in which only the front moves up and down.

[0040]

According to the first aspect of the present invention, there is provided a seat occupant detecting apparatus applied to a seat having a lift mechanism for moving a seat cushion up and down, wherein the seat cushion is detected based on an input load acting on the lift mechanism. Since the occupant detection means for detecting at least one of the presence or absence of the occupant and the body weight is provided, the manufacturing cost can be reduced and the occupant sitting on the seat can be detected.

According to a second aspect of the present invention, in the seat occupant detecting apparatus according to the first aspect, the occupant detecting means has a load detecting means for detecting a pressing force acting on an output shaft of a lifter motor of the lift mechanism. Therefore, there is an excellent effect that the manufacturing cost can be reduced and the occupant sitting on the seat can be detected.

According to a third aspect of the present invention, in the seat occupant detection device of the first aspect, the occupant detection means includes a current value detection means for detecting a starting current value of a lifter motor of the lift mechanism. This has an excellent effect that the manufacturing cost can be reduced and an occupant sitting on the seat can be detected.

According to a fourth aspect of the present invention, in the seat occupant detection device according to any one of the first to third aspects, the occupant detection means corrects the detected value based on the swing angle of the lift mechanism. Because of the means, in addition to the effect according to any one of claims 1 to 3, there is an excellent effect that at least one of the presence or absence of the occupant seated on the seat cushion and the weight can be accurately detected.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a main part of a seat occupant detection device according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG.

FIG. 3 is a perspective view of the occupant detection device for a seat according to the first embodiment of the present invention, as viewed obliquely from the front of the seat.

FIG. 4 is a schematic side view showing a rear portion of the seat occupant detection device according to the first embodiment of the present invention.

FIG. 5 is an operation explanatory view showing a rear portion of the seat occupant detection device according to the first embodiment of the present invention.

FIG. 6 is a schematic side view showing a main part of a seat occupant detection device according to a second embodiment of the present invention.

FIG. 7 is a graph showing a starting current value of a lifter motor in a seat occupant detection device according to a second embodiment of the present invention.

FIG. 8 is a schematic side view showing a rear part of a seat occupant detection device according to another embodiment of the present invention.

FIG. 9 is a schematic side view showing a rear portion of a seat occupant detection device according to another embodiment of the present invention.

FIG. 10 is a perspective view showing a seat occupant detection device according to a conventional embodiment.

[Explanation of symbols]

12 Seat 16 Seat cushion 26 Front lifter rod 30 Front vertical link 34 Seat cushion side frame 38 Rear lifter rod 40 Rear lifter link 43 Connecting rod 44 Motor for lifter 44A Motor shaft for motor for lifter 50 Joint 52 Case 52 Load switch (occupant detection) Load detecting means) 56 occupant detecting circuit (occupant detecting means) 60 current detecting circuit (current detecting means of occupant detecting means) 64 load meter (load detecting means of occupant detecting means) 66 load estimating circuit (occupant detecting means) 62 Angle meter (correction means)

Claims (4)

[Claims] 1. A seat occupant detection device applied to a seat having a lift mechanism for moving a seat cushion up and down, the presence / absence and weight of an occupant seated on the seat cushion based on an input load acting on the lift mechanism. An occupant detection device for a seat, comprising: occupant detection means for detecting at least one of the following. 2. The occupant detection device according to claim 1, wherein the occupant detection means includes a load detection means for detecting a pressing force acting on an output shaft of a lifter motor of the lift mechanism. 3. The seat occupant detection device according to claim 1, wherein the occupant detection means includes current value detection means for detecting a starting current value of a lifter motor of the lift mechanism. 4. The seat occupant detection device according to claim 1, wherein said occupant detection means has a correction means for correcting a detection value based on a swing angle of a lift mechanism. .