JP2001074575A - Seating sensor, and seating condition detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect seating conditions, such as weight and posture of an occupant. SOLUTION: This seating condition detector 10 is provided with load sensing switches 14-22, and the respective switches 14-22 are embedded into seat face 12A of a seat 12. Each of the switches 14-22 is composed of contact switches, layered vertically to output on- and off-conditions of the each switch 14-22 to a determination part 24. The determination part 24 determines the presence of a pattern consistent therewith from among plural kinds of on- and off- patterns corresponding to predetermined various postures, so as to estimate a posture, i.e., seating condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seating sensor and a seating state detecting device, and more particularly to a seating sensor and a seating state detecting device capable of detecting a seating state of a vehicle seat.

[0002]

2. Description of the Related Art In recent years, an airbag system capable of reducing the impact of an emergency in an automobile or the like has been often mounted on a driver's seat and a passenger seat. The airbag system detects an emergency condition based on, for example, acceleration detected by an acceleration sensor and activates the airbag by igniting a priming agent. Thereby, the occupant sitting on the seat can be protected.

[0003] However, in the conventional airbag system, the airbag operates in an emergency state regardless of the presence or absence of a passenger in the passenger seat. In addition, the airbag was operated uniformly regardless of whether the weight was heavy, light, or large and small.

In order to solve this problem, a seating sensor in which a plurality of switch groups each including a plurality of switches having different operation loads are arranged is provided in a seat to obtain different signals depending on the body weight, for example, an assistant. There is disclosed a technique of controlling the airbag not to be activated when no person is on the seat or when a child or infant is on the seat (Japanese Patent Application Laid-Open No. Hei 10-21537).

[0005]

However, in the above prior art, a plurality of switches having different operation loads are arranged in a plane, and the operation load of the switch that is turned on is detected. Therefore, a large load is applied to only one switch. Even when it is applied, it may be determined that the load is small.

In some cases, the operation and non-operation of the airbag are controlled in accordance with the posture of the occupant. However, in the above-described prior art, since the switch is simply used to detect the load, the posture of the occupant is controlled. It is not possible to detect even the seated state including this.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a seating sensor and a seating state detecting device capable of accurately detecting a seating state such as the weight and posture of an occupant. It is.

[0008]

According to a first aspect of the present invention, there is provided a seating sensor comprising: a pair of electrodes; an insulator sandwiched between the pair of electrodes; A seating sensor that includes a plurality of contact switches that are brought into conduction by being pressed from at least one side of the pair by contacting the electrode pairs, wherein the contact switch detects conduction by detecting conduction of the plurality of contact switches. Connecting means having a contact portion having a size smaller than the size of the portion that can be pressed to be pressed is provided between the pressing directions of the plurality of contact switches and connecting the plurality of contact switches. It is characterized by doing.

The contact switch has a configuration in which, for example, a metal electrode pair is provided, and an insulator is interposed between the electrode pair.
Thereby, the electrode pair is in a non-contact state, that is, a non-conductive state when not pressed. The electrode pair is brought into contact with the electrode pair by being pressed from at least one side. The seating sensor includes a plurality of such contact switches, and detects seating based on the conduction state of the plurality of contact switches.

In such a seating sensor, the plurality of contact switches are connected in the pressing direction of the contact switches by connecting means. In the connection means, the size of the contact portion that contacts the contact switch, that is, the size of the contact area, is smaller than the size of a portion that can be pressed to make the contact switch conductive. The magnitude of the pressing force applied to the contact portion differs depending on the size of the area of the contact portion. If the area is small, the pressing force is concentrated. Thereby, the pressing force is applied to the contact switches on the downstream side in the pressing direction in a concentrated manner, so that the contact switches on the downstream side in the pressing direction can be made conductive.
Therefore, it is possible to easily detect the magnitude of the pressing force applied to the same location from the conduction state of the plurality of connected contact switches.

[0011] The connecting means can set the size of the contact portion according to the pressing force when the contact switch is turned on. For example,
If it is desired to increase the pressing force in the conductive state, the area of the contact portion is increased, and if it is desired to reduce the pressing force, the area of the contact portion is reduced. Since it is sufficient to set the size of the contact portion, that is, the area of the contact portion,
The pressing force when the contact switch is turned on can be easily set. The contact switches to be connected may be the same or different.

It is preferable that the plurality of contact switches connected by the connecting means have different stiffnesses of the electrodes contacted by the connecting means. This makes it possible to set the pressing force at which the plurality of connected contact switches are brought into the conductive state. For example, the rigidity of the electrode contacting the upper side of the connecting means is
When the pressing force is applied to the upper contact switch by making the rigidity of the electrode contacting the lower side of the connecting means larger, the pressing force is concentrated on the connecting means. This allows
First, the lower contact switch becomes conductive, and when the pressing force further increases, the upper contact switch becomes conductive.
As described above, by adjusting the rigidity of each of the electrodes contacted by the connecting means, the pressing force at which each of the plurality of contact switches becomes conductive can be freely set.

Since the contact switches are connected in the pressing direction, there are cases where the contact switches having different magnitudes of the pressing force for bringing into a conductive state are arranged in a plane, that is, in a direction substantially perpendicular to the pressing direction. By comparison, the magnitude of the pressing force applied to the same location can be accurately detected.

According to a fourth aspect of the present invention, there is provided a seating state detecting apparatus for estimating a seating state based on a combination of the plurality of seating sensors according to the first or second aspect and the conduction state of the contact switch. And a state estimating means.

The seating state detecting device has a plurality of seating sensors. By arranging the plurality of seat sensors, for example, in a plane, it is possible to grasp the magnitude of the pressing force applied over a wide range due to seating. The seating state estimating means is:
The seating state is estimated based on a combination of the conduction states of the contact switches of the plurality of seating sensors. In this seated state,
For example, the weight and posture of the occupant, the weight of luggage, and the like are included.

For example, the seating state estimating means can estimate the seating state on the basis of the number of contact switches in the conductive state. That is, for example, when the number of conductive contact switches is less than a predetermined value, the pressing force is small, for example, it can be estimated that a child is seated, and when the number of conductive contact switches is equal to or more than a predetermined value, It can be assumed that the pressing force is large and an adult is seated. Thus, the weight of the occupant can be easily estimated from the number of the contact switches in the conductive state.

Further, the seating state detecting means can estimate the seating state based on the distribution of the contact switches in the conductive state. For example, in the case where a plurality of seat sensors are arranged in a plane in front of and behind the seat of the automobile, on the window side, inside, etc., for example, the contact switches of the seat sensors arranged on the window side are in a conductive state and arranged on the driver seat side. When the contact switch of the seating sensor is in a non-conductive state, it can be estimated that the occupant is sitting on the window side.

Further, when only one contact switch of the seating sensor disposed on the window side is in a conductive state, it can be estimated that a child is seated when two or more of the contact switches are conductive, and so on. With this simple configuration, the occupant's posture can be estimated based on the distribution of the conduction state of the contact switches, that is, the load distribution.

According to a fifth aspect of the present invention, the seating sensor is provided on a vehicle seat, and further includes an acceleration detecting means for detecting an acceleration of the vehicle. It is characterized in that the seating state is estimated based on a combination of the conduction states of the contact switches.

The seating sensor is provided on the seat of the vehicle, and the acceleration of the vehicle is detected by acceleration detecting means. Further, the acceleration detecting means may detect whether the vehicle is accelerating in the acceleration direction, for example, in the front-rear direction or the up-down direction of the vehicle. The seating state estimating means estimates the seating state based on a combination of the conduction states of the contact switches in consideration of the detected acceleration. For example, when the acceleration is equal to or higher than a predetermined value, it can be considered that an extra load corresponding to the acceleration is applied as compared with the case where the acceleration is zero. Therefore, the combination of the conduction states of the contact switches is corrected. The seating state is estimated based on the combination of the corrected conduction states. Thus, the seating state can be accurately estimated even in the running state of the vehicle.

The invention according to claim 6 further comprises storage means for storing the conduction state of the contact switch in a time series.
The seating state estimating means estimates a seating state based on a combination of conduction states of the plurality of contact switches stored in a time series.

The storage means stores the conduction state of the contact switches in a time series. For example, the conduction state of a plurality of contact switches at predetermined time intervals is stored. The seating state estimating means is:
The seating state is estimated based on a combination of the conduction states of the plurality of contact switches stored in time series. For example, take the average of the combination of conduction states of a plurality of contact switches,
From this, the seating state is estimated. Thereby, the reliability of the estimated sitting state can be improved.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] Hereinafter, a first embodiment will be described in detail with reference to the drawings.

FIG. 1 is a top view of an unillustrated passenger seat 12 of an automobile to which a seating state detecting device 10 according to the first embodiment is attached. The seating state detection device 10 includes load detection switches 14 to 22 as seating sensors, and a determination unit 24. The load detection switches 14 to 22 are embedded in the seat surface 12A of the seat 12 arranged on the passenger seat side of a vehicle (not shown), for example. The load detection switches 14 to 22 are connected to a determination unit 24 as seating state detection means.

The load detecting switch 14 is embedded in the front of the seat surface 12A. The load detection switch 16 is embedded in the center of the seat surface 12A. The load detection switch 18 is embedded on the rear side of the seat surface 12A. The load detection switch 20 is embedded on the window side (the right side in FIG. 1) of the seat surface 12A. The load detection switch 22 is embedded on the driver's seat side (the left side in FIG. 1) of the seat surface 12A.

As shown in FIG. 2, the load detecting switches 14 to 22 are a pair of pressing contact switches 26A and 26A.
B, a spacer 28 as a connecting means.
The contact switch 26 is long as shown in FIG.
As shown in FIG. 4, a long insulator 32 is sandwiched between both sides of a pair of metal electrodes 30A and 30B as an electrode pair composed of a long copper plate or the like. Covered with the conductive film 34. The contact switches 26A and 26B are the same.

The upper metal electrode 30A, that is, the side to which a load is applied, has low rigidity and is easily deformed to some extent, and the lower metal electrode 30B has high rigidity and is hardly deformed. That is, the metal electrode 30A and the metal electrode 30B have different rigidities. This allows
When a load is not applied from above the contact switch 26, the metal electrodes 30A and 30B are in a non-conductive state (OFF state) because they are not in contact with each other, but a load is applied (pressed) from above the contact switch 26. Then, the metal electrode 30A is deformed and comes into contact with the metal electrode 30B to be in a conductive state (ON state). In addition, the magnitude of the pressing required to be turned on, that is, the magnitude of the load is determined by the magnitude of the width and thickness of the
It can be adjusted by adjusting the width and thickness of the insulator 32.

Such contact switches 26A, 26B
Has a length substantially equal to the length of the contact switches 26A and 26B as shown in FIG.
Are stacked with a spacer 28 having a width smaller than the width of.

As a result, the load applied to the entire upper contact switch 26A is applied to the lower contact switch 26B via the spacer 28 having a width smaller than the width of the contact switches 26A and 26B. A load will be applied. Therefore, the on / off state of the contact switches 26A and 26B differs depending on the magnitude of the load. That is,
As shown in FIG. 5, when no load is applied, the contact switches 26A and 26B are both off, and when the load is gradually applied, only the contact switch 26B is first turned on. When the load further increases, the contact switch 26A also turns on. That is, in the case of light load, the contact switch 26
When only B is turned on and the load is heavy, contact switch 26A
Also turns on. In FIG. 5, the number of arrows indicates the magnitude of the load.

The magnitude of the load and the contact switch 26
The relationship between the on and off states of A and 26B is the width of the spacer,
It is determined by the magnitude of the load at which the contact switches 26A and 26B are turned on. This is set in advance to have a desired relationship. For example, when the load is 0 kg or more and less than Pkg, both the contact switches 26A and 26B are turned off, and when the load is more than Pkg and less than Qkg, only the contact switch 26B is turned on and the load is Qkg or more. In this case, the width of the spacer, the magnitude of the load at which the contact switches 26A and 26B are turned on, that is, the width and thickness of the metal electrode 30, the width of the insulator 32, and the like are set so that the contact switch 26A is also turned on. Adjust the thickness.

FIG. 6 is a block diagram of the seating state detecting device 10. As shown in FIG. As shown in FIG. 6, the determination unit 24
6, a ROM 38, a RAM 40, and an input / output interface circuit (I / O) 42 each including a microcomputer connected by a bus 44 so that data and commands can be transmitted and received. The ROM 38 stores a control program and the like to be described later.

The I / O 42 includes load detection switches 14 to
One end of each of the 22 contact switches 26A and 26B and one end of the pull-down resistors 48A and 48B are connected to each other.
The other ends of the pull-down resistors 48A and 48B are each grounded. The other ends of the contact switches 26A and 26B are respectively connected to a constant voltage power supply Vcc. Thereby, for example, when the contact switch 26A is off, the corresponding I / O4
A low level (0) is input to the input port 2 and a high level (1) is input when it is on.

In the CPU 36, each of the contact switches 26
The on / off states of A and 26B are fetched, and based on this, the seating state of the seat 12 is detected.

Next, as an operation of the first embodiment, a control routine executed by the CPU 36 of the determination section 24 will be described with reference to a flowchart shown in FIG.

In step 100 shown in FIG. 7, all the contact switches 26A, 26A of the load detection switches 14 to 22 are set.
Capture the on / off state of B.

In the next step 102, step 100
The seating state (posture) of the seat 12 is specified based on the on / off patterns of the contact switches 26A and 26B, that is, the load distribution. This is performed, for example, by determining whether a matching pattern exists from a plurality of types of patterns corresponding to various postures determined in advance by experiments or the like.

An example of the relationship between the on / off state of each contact switch and the attitude is shown below.

[0038]

[Table 1]

In the table, "front side", "center", "rear side", "window side", and "driver's side" indicate load detection switches 14, 16, 18, 20, and 22, respectively, and "light". Indicates the contact switch 26B, and “heavy” indicates the contact switch 26A. And, ● indicates that the contact switch is on. Note that patterns 1 to 15 correspond to FIGS. 8A to 8O, respectively.

As shown in Table 1, the pattern 1 includes the contact switches 26A, 26A of the load detection switches 14 to 22 respectively.
6B are all off. In such a case, FIG.
It can be estimated as shown in FIG.

Pattern 2 includes load detection switches 14 to 2
2 are all on, and in such a case, it can be estimated that an adult is sitting in the center of the seat 12 as shown in FIG.

The pattern 3 includes contact switches 26A of the load detection switch 14 arranged on the front side of the seat 12;
26B are both on and the other contact switches 26
A and 26B are all off. In such a case, it can be estimated that an adult is sitting at the front end of the seat 12 as shown in FIG.

The pattern 4 includes contact switches 26A, 26A, of the load detection switches 14, 16, 20, 22 other than the load detection switch 18 disposed on the rear side of the seat 12.
26B are all on, and in such a case, FIG.
As shown in (D), it can be estimated that the adult's hips are at the front end of the seat 12 and the back rests on the back of the seat 12.

Pattern 5 indicates that all contact switches 26
A and 26B are on, and in such a case, FIG.
As shown in (E), it can be estimated that an adult sits deeply on the seat 12 and leans backward.

In the pattern 6, all the contact switches 26A and 26B of the load detection switches 14 to 20 other than the load detection switch 22 arranged on the driver's seat side are all on,
In such a case, as shown in FIG. 8F, it can be estimated that the adult is sitting near the window.

The pattern 7 includes load detection switches 14, 16, 1 other than the load detection switch 20 arranged on the window side.
All of the contact switches 26A and 26B of each of the switches 8 and 22 are turned on. In such a case, it can be estimated that an adult is sitting on the driver's seat side as shown in FIG. 8 (G). .

The pattern 8 includes the load detection switches 14 to 2
Only the respective contact switches 26B are turned on. In such a case, it can be estimated that the child is seated at the center of the seat 12 as shown in FIG.

The pattern 9 corresponds to the contact switch 26 of the load detection switch 16 disposed at the center of the seat 12.
A and 26B are on, and the other contact switches 26
A and 26B are all off. In such a case, FIG.
As shown in (I), it can be estimated that the child is standing in the center of the seat 12.

The pattern 10 includes contact switches 26A of the load detecting switches 16 and 18 disposed at the center and rear of the seat 12 and contact switches 26A and 26B of the load detecting switches 20 disposed on the window side of the seat 12. Is on, and in such a case, as shown in FIG. 8 (J), it can be estimated that the child is standing near the window or standing with his knees.

The pattern 11 includes contact switches 26A of load detection switches 16 and 18 disposed at the center and rear of the seat 12, and contact switches 26A of load detection switches 22 disposed at the driver's seat side of the seat 12. , 26
B is on, and in such a case, as shown in FIG. 8K, it can be estimated that the child is standing on the driver's seat side or standing on his knees.

The pattern 12 is a contact switch 26A of the load detection switch 14 disposed on the front side of the seat 12.
In this case, it is assumed that the child is seated on the front end of the seat and leans forward, for example, with the hand on the dashboard, as shown in FIG. 8 (L). Can be.

The pattern 13 is a contact switch 2 of each of the load detection switches 14 to 20 arranged on the side other than the driver's seat side.
6B is on, and in such a case, it can be estimated that the child is sitting near the window as shown in FIG. 8 (M).

In the pattern 14, the contact switches 26B of the load detection switches 14 to 18 and 22 arranged other than on the window side are turned on. In such a case, as shown in FIG. It can be estimated that the driver is sitting on the driver's seat side.

The pattern 15 includes the load detection switches 14 to
Each of the contact switches 26B is turned on. In such a case, it can be estimated that the child sits deeply on the seat 12 and leans backward as shown in FIG. 8 (O).

Table 1 is shown below, rearranged by the number of ON of the contact switches.

[0056]

[Table 2]

Here, group A is a case where the number of ONs of the contact switches is 0, group B is a case where the number of ONs of the contact switches is 1, and group C is a case where the number of ONs of the contact switches is 2 , Group D has four contact switches ON, and Group E has five contact switches ON.
In this case, the group F shows the case where the number of ON of the contact switch is eight, and the group G shows the case where the number of ON of the contact switch is ten. That is, the magnitude of the load can be estimated by counting the number of ON of the contact switches 26A and 26B.

In step 104, information on the posture estimated in this manner, for example, a pattern No. is output to an airbag control device (not shown). Thus, the airbag control device (not shown) controls the airbag based on the posture information output from the seating state detection device 10. For example, when it is dangerous to operate the airbag, for example, as shown in FIG. 8 (I), the airbag is not operated when the child is standing on the seat 12. As a result, the impact load in an emergency can be reduced.

Further, since the load detection switch is configured such that the contact switches are connected in the vertical direction, that is, in the load direction (pressing direction), when the contact switches having different loads to be turned on are arranged side by side in a plane. In comparison, the magnitude of the load at the same point can be accurately detected. Thereby, the posture, that is, the sitting state can be accurately detected.

Further, since the posture is estimated from the on / off state of each contact switch, an amplifier for amplifying an analog output signal, such as a case of measuring a load according to the magnitude of an output signal, such as a load sensor, becomes unnecessary. The device can be configured at low cost. In addition, durability and maintainability can be improved by using a contact switch having a simple structure.

It is also possible to simply count the number of ON times of the contact switches, estimate the weight from the count value, that is, the sum of the loads, and output the estimated weight to an airbag control device (not shown). In this case, the airbag control device can perform control such as not operating the airbag when the estimated weight is equal to or less than the predetermined value. Thus, the weight of the occupant can be estimated with a simple configuration.

Further, in the present embodiment, the load detection switch is configured by stacking two contact switches, but three or more contact switches may be stacked. In this case, the load range to be detected may be adjusted by appropriately changing the width of the spacer 28 sandwiched between the contact switches.

Instead of estimating the attitude from the ON / OFF pattern of each contact switch detected once, the ON / OFF pattern of each contact switch is stored in the RAM 40 at predetermined time intervals, that is, in chronological order. Then, an average of the on / off patterns of the plurality of contact switches stored in the RAM 40 may be taken, and the posture may be estimated from this. The average of the on / off pattern of each contact switch can be obtained, for example, by comparing the number of times of on and off with each contact switch, and setting a larger one as a correct output. As described above, since the posture is estimated from the average of the plurality of on / off patterns stored in time series, the reliability of the estimated posture can be improved.

It is to be noted that the posture estimated in time series is not used for estimating the posture by taking the average of the on / off patterns.
M40 may be stored, and at a predetermined timing, the most frequent posture among the plurality of estimated postures may be output as the correct posture.

[Second Embodiment] Next, a second embodiment will be described.

FIG. 9 shows a seating state detecting device 10 'according to the second embodiment. The same parts as those of the seating state detecting device 10 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The seating state detecting device 10 ′ includes an acceleration sensor 50, and the acceleration sensor 50
4 is connected. Specifically, the determination unit 2 shown in FIG.
4 I / O 42.

The acceleration sensor 50 detects the acceleration of the vehicle (not shown) and the direction of the acceleration, that is, whether the acceleration is generated in the front-rear direction or the vertical direction of the vehicle, and outputs it to the determination unit 24. . Thus, if acceleration is generated in the front-rear direction, the vehicle can be estimated to be in an acceleration / deceleration state, and if acceleration is generated in the vertical direction, it can be estimated that the vehicle is in a vibrating state. Can be. The determination unit 24 detects the sitting state in consideration of the detected acceleration and the acceleration direction.

Next, as an operation of the second embodiment, a control routine executed by the CPU 36 of the determination section 24 will be described with reference to a flowchart shown in FIG.

In step 200 shown in FIG. 10, all the contact switches 26A,
The on / off state of 6B is captured.

In the next step 202, the acceleration sensor 5
From 0, the acceleration and the acceleration direction are detected. Then, in step 204, each of the contact switches 26A, 26B considering the acceleration and the acceleration direction taken in in step 202
Of the seat 12 is specified based on the on / off pattern of the seat 12, that is, the load distribution. For example, when the vehicle is accelerating in the forward direction, the occupant's posture is inclined backward, and the load detected by the load detection switch 18 disposed on the rear side of the seat 12 is larger than that in the non-accelerated state. Can be estimated.

Therefore, for example, when the acceleration is larger than a predetermined value and the acceleration direction is the forward direction of the vehicle, the contact switch 26 of the load detection switch 18
Even when both A and 26B are on, it is assumed that an additional load for the acceleration is applied, and only the contact switch 26B is on. In other words, the on / off pattern of each contact switch is corrected according to the acceleration and the acceleration direction. Then, the posture is specified by searching for a pattern that matches the corrected on / off pattern from a plurality of types of patterns shown in Table 1.

Similarly, when the vehicle is accelerating downward due to, for example, the vibration of the vehicle, the load applied to the seat 12 is larger than that in the non-accelerated state. Therefore, even in such a case, when the acceleration is larger than the predetermined value and the acceleration direction is the downward direction of the vehicle, even if both of the contact switches 26A and 26B are on, only the contact switch 26B is provided. The posture is specified as not being turned on.

On the other hand, when the vehicle is accelerating upward, the load applied to the seat 12 is smaller than that in the non-accelerated state.
Even when both A and 26B are off, the posture may be specified assuming that only the contact switch 26B is on or that both contact switches 26A and 26B are on according to the magnitude of the acceleration.

In step 206, information on the posture estimated in this manner, for example, the pattern No. is output to an airbag control device (not shown). Thus, the airbag control device (not shown) controls the airbag based on the posture information output from the seating state detection device 10.

As described above, since the posture is estimated in consideration of the acceleration and the acceleration direction of the vehicle, the posture can be accurately estimated even while the vehicle is running.

In the above description, the case where the on / off pattern of the contact switch is corrected in accordance with the acceleration and the acceleration direction has been described. However, the posture is specified using the on / off pattern of the contact switch when the acceleration is substantially zero. You may. Further, the relationship between the on / off pattern of the contact switch and the attitude in consideration of the acceleration and the acceleration direction and the attitude are obtained in advance (the acceleration and the acceleration direction are added to the parameters in Table 1), and the attitude is estimated based on this. Good.

[0078]

As described above, according to the first aspect of the present invention, there is an effect that the magnitude of the pressing force applied to the same location can be accurately detected.

According to the second aspect of the present invention, it is possible to easily set the pressing force when the contact switch is turned on.

According to the third aspect of the present invention, it is possible to set the pressing force at which each of the plurality of connected contact switches becomes conductive.

According to the fourth aspect of the present invention, there is an effect that the seating state such as weight and posture can be easily estimated with a simple configuration.

According to the fifth aspect of the present invention, the seating state can be accurately estimated even in the running state of the vehicle.

According to the invention of claim 6, there is an effect that the reliability of the estimated sitting state can be enhanced.

[Brief description of the drawings]

FIG. 1 is a top view of a seat to which a seating state detecting device according to a first embodiment is attached.

FIG. 2 is a side view of the load detection switch.

FIG. 3 is a perspective view of a contact switch.

FIG. 4 is a sectional view taken along line A-A 'of FIG.

FIG. 5 is a diagram for explaining an on / off state of a load detection switch.

FIG. 6 is a block diagram of a seating state detecting device.

FIG. 7 is a flowchart illustrating a control routine executed by a CPU according to the first embodiment.

FIG. 8 is a diagram illustrating an example of a sitting state.

FIG. 9 is a top view of a seat to which a seating state detecting device according to a second embodiment is attached.

FIG. 10 is a flowchart illustrating a control routine executed by a CPU according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Seating state detection device 12 Seat seat 12A Seat surface 14, 16, 18, 20, 22 Load detection switch 24 Judgment part 26 Contact switch 28 Spacer 30 Metal electrode 32 Insulator 34 Insulating film 36 CPU 38 ROM 40 RAM 42 I / O 44 bus 48 pull-down resistor 50 acceleration sensor

Claims (8)

[Claims] A contact, comprising: an electrode pair; and an insulator sandwiched between the electrode pair, wherein the contact is made conductive by being pressed from at least one side of the electrode pair. A seating sensor including a plurality of switches and detecting seating based on a conduction state of a plurality of contact switches, wherein a contact portion having a size smaller than a size of a portion that can be pressed to make the contact switches conductive. A seating sensor provided with connecting means having a plurality of contact switches between pressing directions of the plurality of contact switches, and connecting the plurality of contact switches. 2. The seating sensor according to claim 1, wherein the size of the contact portion is set according to a pressing force when the contact switch is turned on. 3. The seating sensor according to claim 1, wherein the plurality of contact switches connected by the connecting means have different stiffness of each of the electrodes contacted by the connecting means. . 4. A seating state detection comprising: a plurality of seating sensors according to claim 1 or 2; and a seating state estimating means for estimating a seating state based on a combination of conduction states of the contact switches. apparatus. 5. The seat sensor is provided on a seat of the vehicle, and further includes acceleration detecting means for detecting acceleration of the vehicle, wherein the seating state estimating means detects the detected acceleration and a conduction state of the contact switch. The seating state is estimated based on the combination.
The seating state detecting device according to any one of the preceding claims. 6. A storage unit for storing a conduction state of the contact switch in a time series, wherein the seating state estimating unit is seated based on a combination of conduction states of the plurality of contact switches stored in a time series. The seating state detecting device according to claim 4 or 5, wherein the state is estimated. 7. The seating state according to claim 4, wherein the seating state estimating means estimates the seating state based on the number of the contact switches in a conductive state. Detection device. 8. The seating state according to claim 4, wherein the seating state estimating means estimates the seating state based on a distribution of the contact switches in a conductive state. Detection device.