JP2001169859A - Seating condition sensing instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sense seating conditions with a high degree of accuracy regardless of variations in temperature of a seat in a seating condition sensing instrument disposed in seats of a car used for sensing the seating conditions of passengers, or the like. SOLUTION: In the seating condition sensing instrument for sensing the seating conditions of passengers, or the like, with respect to a seat 11 by means of a seating pattern sensor 14 disposed in the seat 11, air heated or cooled by an air conditioner 22 for sensors can be fed to a seat cushion pad 13 of the seat 11. Temperatures of the pad 13 are sensed by means of a seat temperature sensor 23, and a control unit 24 controls the conditioner 22 based on the result of sensing, to feed air of such temperatures that the hardness of the pad 13 is kept within a proper sensing range of the sensor 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seating detecting device, and more particularly to a seating detecting device disposed on a vehicle seat for detecting a seating state of an occupant or the like.

[0002]

2. Description of the Related Art In recent years, airbags and seatbelts have been determined according to the physique of an occupant (whether an adult or a child), the presence or absence of an occupant in a seat, and the presence or absence of a child restraint device (hereinafter collectively referred to as a seated state). It has been proposed to control the operation of In order to perform this control, it is necessary to detect a sitting state. The detection of the seating state can be determined by the distribution of a load (hereinafter, referred to as a seating load) by which the occupant or the child restraint device presses the seat, and the detection is generally performed by using a seating detection device provided on the seat. The detection process is being performed.

As this seating detection device, there is one disclosed in, for example, Japanese Patent Application Laid-Open No. H11-129860. The seat detection device disclosed in the publication is used for controlling an airbag, and is provided on a seat cushion pad of a seat on which an occupant sits. This seating detection device has a lattice-shaped detection pattern, and is configured to determine a seating state by detecting a deformation of the detection pattern according to the seating state. The control device is configured to control the driving of the airbag device according to the result of this determination.

[0004]

By the way, the hardness of the seat cushion pad changes greatly depending on the temperature inside the vehicle. That is, in cold regions, the room temperature reaches minus several tens of degrees, and under hot summer sun, it rises to room temperature plus several tens of degrees. Therefore, the hardness of the seat cushion pad changes with the temperature change, and the hardness increases in a low temperature environment and decreases in a high temperature environment.

Therefore, in the conventional configuration in which the seat detecting device is simply disposed on the seat cushion pad, a change in the hardness of the seat cushion pad affects the detection accuracy of the seat detecting device. That is, in a low-temperature environment, the hardness of the seat cushion pad is higher (harder) than a hardness range in which the seat detection device can appropriately detect (hereinafter, referred to as an appropriate hardness range). In this case, even if the occupant is seated, the deformation of the seat cushion pad is reduced, and the detection output of the seat detection device is reduced.

Conversely, in a high-temperature environment, the hardness of the seat cushion pad is lower (softer) than the appropriate hardness range. In this case, when the occupant is seated, the seat cushion pad is greatly deformed, and the detection output of the seat detection device is also increased. Therefore, in the conventional seat detection device, when the hardness of the seat cushion pad changes with the change in the environmental temperature, this is reflected in the detection result of the seat detection device, and the seating state cannot be accurately detected. The change in the determination criterion due to the temperature change can be performed by an algorithm of a computer provided in the seat detection device. However, when trying to cope with the algorithm, it is necessary to grasp the cushion characteristics at each temperature, which requires a huge amount of data. Further, since the temperature of the seat changes with the start of traveling, the algorithm must read a program suitable for the seat temperature and determine the occupant, resulting in complicated control.

[0007] The present invention has been made in view of the above points, and by maintaining the temperature of the seat cushion pad at a predetermined temperature so that the hardness of the seat cushion pad is within an appropriate hardness range, the accuracy of the control can be improved by a simple control process. An object of the present invention is to provide a seating detection device capable of performing high seating detection.

[0008]

According to the present invention, there is provided a seating detection device for detecting a seating state of an occupant or the like on a seat by a seating pattern sensor disposed in the seat. A seat temperature holding means for holding a temperature of the sheet within an appropriate detection temperature range of the seating pattern sensor by supplying a temperature adjusting medium to the sheet is provided.

According to the present invention, the temperature adjusting medium can be supplied to the sheet. Therefore, by changing the temperature of the temperature adjustment medium, the temperature of the sheet also changes, and accordingly, the hardness of the sheet also changes. That is, by controlling the temperature of the temperature adjusting medium, the hardness of the sheet can be controlled. Further, in the present invention, the seat temperature holding means is provided to hold the temperature of the seat within an appropriate detection temperature range of the seating pattern sensor. Thereby, the hardness of the seat is controlled within a hardness range in which the seating pattern sensor can appropriately perform the detection processing, and thus the seating pattern sensor can always perform highly accurate seating detection.

Further, after the start of traveling, the seat is maintained at an appropriate temperature by the seat temperature holding means as described above. Therefore, in order for the seating detection device to detect the seating state, data and programs for the appropriate temperature are required. And complicated control can be eliminated.

[0011]

Next, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show a seat 11 provided with a seating detection device 10 according to one embodiment of the present invention. FIG. 1 is a configuration diagram of the seating device 10, and FIG.
3 is a sectional view taken along line AA in FIG. 1 and FIG.
Is a plan view of the seat 11. FIG.

The seating detecting device 10 is incorporated in a seat 11 of a vehicle, and determines the physique of an occupant seated on the seat 11 and a load other than the occupant (for example, a child restraint device).
Is used to determine whether or not is mounted on the seat 11. In the following description,
An occupant that is a person and a mounted object (for example, a child restraint or the like) that may be mounted on a seat by a person other than a person are referred to as an occupant.

The seat 11 is roughly composed of a seat cushion pan 12, a seat cushion pad 13, and a slab 1.
5, the seat back pad 16 and the like. In addition, the seating detection device 10 generally includes a seating pattern sensor 14, an air conditioning nozzle 21, and an air conditioner 2 for a sensor.
2, a seat temperature sensor 23, a control device 24, and the like.

First, the components of the seat 11 will be described. The seat cushion pan 12 is formed of a plate-like metal or hard resin. The seat cushion pan 12 is fixed to the floor 17 by a fixing mechanism (not shown). In addition, the seat cushion pan 12
Above the seat cushion pad 13 and the slab 15
Is held.

The seat cushion pad 13 is made of a pad material such as urethane, for example, and a skin material (not shown) is provided on the surface thereof. As described above, since the seat cushion pad 13 uses a pad material such as urethane which is a resin material, the hardness changes with a temperature change as described later in detail. The slab 15 is made of a resin material such as urethane, for example, like the seat cushion pad 13. This slab 15 is fixed to the seat cushion pan 12.

The slab 15 has a configuration in which an air conditioning nozzle 21 and a seat temperature sensor 23 which constitute a seating detection device 10 described later are provided. Further, the seat cushion pad 13 is configured to be detachable from the slab 15, so that the maintenance of the air conditioning nozzle 21 and the seat temperature sensor 23 is improved.

Next, each component of the seating detection device 10 will be described. The seating pattern sensor 14 has a configuration in which a so-called sheet-shaped membrane switch is applied, and has a configuration in which a plurality of detection units 20 are arranged on a sheet-shaped main body 19. Specifically, the seating pattern sensor 14 is a sheet-shaped main body 19 made of a pair of resin films.
A pair of electrodes constituting the detection unit 20 are disposed on the inner surface of the sensor. The pair of electrodes are configured to be opposed to and separated from each other by a spacer interposed between the resin films.

Therefore, when the seating load is applied to the detecting section 20, the pair of electrodes facing and separated from each other conducts, whereby it is possible to detect that the seating load is applied.
Further, the seating pattern sensor 14 according to the present embodiment is configured to detect whether or not the occupant is seated (mounted) and also detect the seated area. For this reason, the detection units 20 are arranged in a lattice shape on the sheet-shaped main body 19, and the individual detection units 20
The configuration is such that the application of the seating load can be output every time.

The seating pattern sensor 14 constructed as described above.
Is a control device 24 for detecting the seating area and controlling the seat hardness.
(Hereinafter, simply referred to as a control device). The control device 24 performs various processes such as presence / absence of an occupant, the physique of the occupant (whether adult or child) and discrimination between the occupant and the child restraint device based on a signal output from the sitting pattern sensor 14, and will be described later. Control processing for maintaining the hardness of the seat cushion pad 13 at a predetermined hardness.

The air conditioning nozzle 21 is housed in a recess formed in the slab 15, as shown in FIG. The air conditioning nozzle 21 has a plurality of discharge holes 25 formed toward the seat cushion pad 13.
In the present embodiment, as shown in FIG.
Is provided so as to face the seat cushion pad 13. However, the number and locations of the air-conditioning nozzles 21 are not limited to this.

The sensor air conditioner 22 includes a connection hose 26.
Is connected to the air-conditioning nozzle 21. This sensor air conditioner 22 has a heater and a cooler inside,
The air is cooled, heated, and dehumidified, and the air (corresponding to the temperature adjusting medium according to claim 1) is supplied to the air conditioning nozzle 21 via the connection hose 26. Therefore, when the air heated by the sensor air conditioner 22 is supplied to the air conditioning nozzle 21 through the connection hose 26 and blows out from the discharge hole 25 to the seat cushion pad 13, the seat cushion pad 13 is heated and its hardness is increased. descend. When the air cooled by the sensor air conditioner 22 is supplied to the air conditioning nozzle 21 and blows out from the discharge holes 25 to the seat cushion pad 13, the seat cushion pad 13
Is cooled and its hardness increases.

Therefore, in the sensor air conditioner 22,
The hardness of the seat cushion pad 13 can be controlled by adjusting the temperature of the air supplied to the air conditioning nozzle 21. Further, since the sensor air conditioner 22 has a dehumidifying function, the humidity of the generated air is low. Therefore, the moisture contained in the seat cushion pad 13 is removed by the low humidity air.

It is known that the moisture contained in the seat cushion pad 13 causes a change in the hardness of the seat cushion pad 13. Therefore, the moisture contained in the seat cushion pad 13 is changed to the sensor air conditioner 22.
By using a configuration in which the air is supplied by air supplied from the outside, it is possible to prevent a change in hardness due to moisture contained in the seat cushion pad 13.

The seat temperature sensor 23 measures the temperature of the seat cushion pad 13. In the present embodiment, one seat temperature sensor 23 is provided substantially at the center of the slab 15, and is separately provided from the seating pattern sensor 14. However, it is also possible to arrange the seat temperature sensor 23 on the seat cushion pad 13, and it is also possible to adopt a configuration in which a plurality of seat temperature sensors 23 are dispersedly arranged on the seat cushion pad 13 or the slab 15. is there.

In a configuration in which a plurality of seat temperature sensors 23 are arranged in a distributed manner, even when a temperature distribution occurs in the seat cushion pad 13, it is possible to detect the temperature distribution. Therefore, a temperature control process for the seat cushion pad 13 described below can be performed according to the temperature distribution, and the accuracy of the temperature control process can be improved.

Further, in this embodiment, the seat temperature sensor 23
Is configured separately from the seating pattern sensor 14,
It is also possible to use the seating pattern sensor 14 as the seat temperature sensor 23. That is, the seating pattern sensor 1
Reference numeral 4 denotes a configuration in which a pair of electrodes constituting the detection unit 20 are arranged opposite to each other on the inner surface of the sheet-shaped body 19 as described above. Each of the electrodes is drawn out of the seating pattern sensor 14 by a wiring pattern.

Generally, the electrical resistance of a metal material changes with a change in temperature, so that the electrical resistance of a wiring pattern also changes with a change in temperature. Therefore, it is also possible to use the seating pattern sensor 14 as the seat temperature sensor 23. The seating pattern sensor 14, the sensor air conditioner 22, and the seat temperature sensor 23 are
It is connected to the. The control device 24 is configured by a microcomputer, and performs a temperature control process of the seat cushion pad 13 and a process of detecting a seated state of the occupant, which will be described below.

FIG. 4 is a flowchart showing a temperature control process of the seat cushion pad 13, and FIG. 5 is a flowchart showing a seating state detecting process for detecting a seating state of an occupant. FIG. 6 is a graph showing temperature-hardness characteristics of the seat cushion pad 13 used in this embodiment. First, the temperature-hardness characteristics of the seat cushion pad 13 used in this embodiment will be described with reference to FIG. As described above, the hardness of the seat cushion pad 13 changes with a change in temperature. Specifically, as shown in FIG.
The hardness H of the seat cushion pad 13 increases as the temperature decreases.

The hardness range in which the seating pattern sensor 14 can accurately detect the seating state can be obtained in advance by experiments or the like. The seating pattern sensor 14 used in the present embodiment is configured such that when the hardness H of the seat cushion pad 13 is between the hardness H1 and the hardness H2 in the drawing (H2 <H).
<H1) is configured so that an accurate sitting state can be detected.

That is, by controlling the temperature of the seat cushion pad 13 so that the hardness of the seat cushion pad 13 is within the range of hardness H1 to H2, it is possible to detect the seating state with high accuracy. In particular,
As shown in the figure, by controlling the temperature of the seat cushion pad 13 so as to be in the range of T1 to T2,
The hardness of the seat cushion pad 13 is in the range of H1 to H2, and an accurate sitting state can be detected.

Subsequently, the above-mentioned seat cushion pad 1
The temperature control process of the seat cushion pad 13 performed based on the temperature-hardness characteristic of No. 3 will be described. FIG.
The temperature control process of the seat cushion pad 13 shown in FIG.
For example, it is a routine process that is started when the engine is started, and thereafter is repeatedly executed at predetermined time intervals. When the temperature control process shown in the figure is started, first, in step 10 (in the figure, the step is abbreviated as S), the controller 2
4 reads the sensor output output from the seat temperature sensor 23, and reads the current temperature T of the seat cushion pad 13.
(Hereinafter, this temperature T is referred to as a detected temperature T).

In the following step 12, it is determined whether or not the detected temperature T calculated in step 10 is lower than the lower limit temperature T1. Here, the lower limit temperature T1 is a lower limit temperature within a temperature range in which the seating pattern sensor 14 can accurately detect a seating state (hereinafter, this temperature range is referred to as an appropriate detection temperature range). Therefore, when the temperature T of the seat cushion pad 13 is lower than the lower limit temperature T1, the hardness of the seat cushion pad 13 becomes higher (harder) than the hardness at which the seating pattern sensor 14 can detect an accurate seating state.

If it is determined in step 12 that the detected temperature T is lower than the lower limit temperature T1, the controller 24
Resets the detection execution flag in step 14 (O
FF), and in step 16, the heater of the sensor air conditioner 22 is started (ON), and the current routine processing ends. When the heater of the sensor air conditioner 22 is activated in step 16, the air heated by the sensor air conditioner 22 is blown from the discharge holes 25 of the air conditioning nozzle 21 to the seat cushion pad 13, and the temperature of the seat cushion pad 13 rises. . Further, since the sensor air conditioner 22 has a dehumidifying function as described above, the humidity of the seat cushion pad 13 is also reduced.

On the other hand, the detection execution flag in step 14 is a flag that is set (ON) when the detected temperature T is within the proper detection temperature range, and is reset (OFF) when the detection temperature T is outside the proper detection temperature range. This detection execution flag is a flag used in the seating state detection processing shown in FIG. Here, the seating state detection processing shown in FIG. 5 will be described. The seating state detection process is also a routine process that is started at the same time as the start of the engine and is repeatedly executed at predetermined time intervals.

In step 32 shown in FIG. 5, the seating state is detected based on the output signal from the seating pattern sensor 14. However, if the output signal from the seating pattern sensor 14 is inaccurate, the detection accuracy of the seating state also decreases. Therefore, in the seating state detection process according to the present embodiment, prior to step 32, step 30 of determining the set state of the detection execution flag is performed. When it is determined in step 30 that the detection execution flag is set (ON) (that is, when the detected temperature T is within the appropriate detection temperature range), the process of step 32 is executed, and the detection execution flag is set. When it is determined that the reset (OFF) has been performed (that is, when the detected temperature T is outside the appropriate detected temperature range), the processing of step 32 is not executed.

With this configuration, only when the detection temperature T is within the appropriate detection temperature range, and therefore when the hardness of the seat cushion pad 13 is within the hardness range in which the seating pattern sensor 14 can accurately detect the seating state. only,
The seating state detection processing will be performed. Therefore, the configuration of the present embodiment can improve the accuracy of the seating state detection processing.

Here, returning to FIG. 4, the description will be continued. If a negative determination is made in step 12 (that is, the detected temperature T
Is determined to be higher than the lower limit temperature T1), the process proceeds to step 18, and if the heater of the sensor air conditioner 22 is being driven, it is stopped. In the following step 20, it is determined whether or not the detected temperature T calculated in step 10 is higher than the upper limit temperature T2. here,
The upper limit temperature T2 is the upper limit temperature of the appropriate detection temperature range. Therefore, when the temperature T of the seat cushion pad 13 is higher than the upper limit temperature T2,
Is lower (softer) than the hardness at which the seating pattern sensor 14 can detect an accurate seating state.

If it is determined in step 20 that the detected temperature T is higher than the upper limit temperature T2, the controller 24
Resets the detection execution flag in step 22 (O
FF), and in step 24, the cooler of the sensor air conditioner 22 is started, and the current routine processing is ended. When the cooler of the sensor air conditioner 22 is activated in step 24, the air cooled by the sensor air conditioner 22 is blown from the discharge holes 25 of the air conditioning nozzle 21 to the seat cushion pad 13, and the temperature of the seat cushion pad 13 decreases. . Also in this case, the humidity of the seat cushion pad 13 is reduced by the dehumidifying function of the sensor air conditioner 22.

When the detection execution flag is reset (OFF) in step 22, as described above, FIG.
In step 30 shown in FIG. Therefore, even when the detected temperature T is higher than the upper limit temperature T2, the seating state detection process of step 32 is prohibited, so that occurrence of erroneous detection of the seating state can be prevented, and the accuracy of the seating state detection process can be improved. Can be.

On the other hand, if a negative determination is made in step 20 (that is, if it is determined that the detected temperature T is lower than the upper limit temperature T2), the process proceeds to step 26, where the cooler of the sensor air conditioner 22 is turned off. If it is being driven, it is stopped. In the following step 28, the detection execution flag is set (ON). As described above, in the present embodiment, the detected temperature T falls within the range between the lower limit temperature T1 and the upper limit temperature T2 (T
Only when it is 1 <T <T2), in other words, only when the hardness H of the seat cushion pad 13 is (H2 <H <H1), the detection execution flag is set (ON) in step 28, and FIG. A seating detection process of step 32 shown is executed.

In this embodiment, the seat temperature sensor 2
The controller 24 drives the air conditioner 22 for the sensor based on the detected temperature T detected by the air conditioner 3. When the detected temperature T is high, the controller 24 blows out cooled air from the air conditioning nozzle 21 to the seat cushion pad 13. Is low, the heated air is blown out to the seat cushion pad 13. Therefore, the seat cushion pad 13 is heated or cooled by the air sent from the sensor air conditioner 22.

Further, as described with reference to FIG. 4, the control device 24 determines the temperature T of the seat cushion pad 13 in the appropriate detection temperature range (T1 to T2) of the seating pattern sensor 14.
The sensor air conditioner 22 is controlled so as to be held inside. Thereby, the hardness H of the seat cushion pad 13 is always maintained within an appropriate hardness range (H2 to H1) in which the seating pattern sensor 14 can appropriately perform the detection processing. Therefore,
According to the seating detection device 10 of the present embodiment, the sensor output of the seating pattern sensor 14 is always stable, and the accuracy of the seating detection process can be improved.

Further, since the temperature T of the seat cushion pad 13 is maintained within the appropriate detection temperature range as described above, the seating detection process executed by the control device 24 can be simplified and required. Data and programs can be reduced in size, and highly accurate seating detection is possible with a simple configuration. In the above-described embodiment, the sensor air conditioner 22 is configured separately from the vehicle room air conditioner.
Each air conditioner can be integrated.

In this embodiment, air (gas) is used as a medium for heating or cooling the seat cushion pad 13, but a liquid such as water may be used. Further, in the present embodiment, the seat cushion pad 13 is made detachable from the slab 15 and the air conditioning nozzle 21 is arranged on the slab 15, but the seat cushion pad 13 and the slab 15 are integrated. Is also good.

[0045]

As described above, according to the present invention, since the seat temperature holding means is provided to maintain the seat temperature within the proper detection temperature range of the seating pattern sensor, the seat hardness of the seating pattern sensor is appropriate. Thus, the accuracy of the seating detection by the seating pattern sensor can be improved.

After the start of traveling, the seat is maintained at an appropriate temperature by the seat temperature holding means as described above. Therefore, in order for the seating detection device to detect the seating state, data and programs of the appropriate temperature are required. And complicated control can be eliminated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining a seating detection device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a plan view of a seat provided with a seating detection device according to an embodiment of the present invention.

FIG. 4 is a flowchart illustrating a control process of a sensor air conditioner performed by a control device in the seating detection device according to one embodiment of the present invention.

FIG. 5 is a flowchart illustrating a seating detection process performed by a control device in the seating detection device according to the embodiment of the present invention;

FIG. 6 is a diagram showing a relationship between hardness and temperature in a seat cushion pad.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Seating detection device 11 Seat 13 Seat cushion pad 14 Seating pattern sensor 15 Slab 17 Floor 21 Air-conditioning nozzle 22 Sensor air conditioner 23 Seat temperature sensor 24 Control device 25 Discharge hole 26 Connection hose

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01L 5/00 101 G01L 5/00 101 F-term (Reference) 2F051 AA01 AB06 AC04 AC07 3B084 JA06 JC00 JC01 3B087 DE08 DE10 3D054 AA03 EE09 EE10 EE31 FF16

Claims (1)

[Claims] 1. A seating detection device for detecting a seating state of an occupant or the like on a seat by a seating pattern sensor disposed in the seat, wherein a temperature adjusting medium is supplied to the seat to reduce a temperature of the seat. A seating detection device comprising a seat temperature holding unit for holding the seating temperature within an appropriate detection temperature range of the seating pattern sensor.