SEAT APPARATUS FOR VEHICLE

Abstract

A seat apparatus for a vehicle including a side support portion that is controlled to be opened and closed depending on a road shape includes a position detecting portion for detecting a position of the side support portion, a sensor provided at the side support portion and detecting a physique of an occupant, a physique detecting portion for detecting the physique of the occupant by means of the sensor while the side support portion is in a full open position, and an initial position determining portion for determining an initial position of the side support portion depending on the physique of the occupant detected by the physique detecting portion.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2006-319614, filed on Nov. 28, 2006, the entire content of which is incorporated herein by reference.

FIELD OF THE INVENTION

This invention generally relates to a seat apparatus for a vehicle. More particularly, this invention pertains to a seat apparatus for a vehicle that controls a side support portion depending on a road shape.

BACKGROUND

A known seat apparatus for a vehicle is disclosed in JP2590875B. The seat apparatus disclosed includes a capacitance sensor for determining whether or not an occupant is seated on a seat so as to perform an open and close control on a side support portion. According to the seat apparatus disclosed, the capacitor sensor is used only for determining presence or absence of an occupant and is not used for changing, depending on the physique of an occupant, a support position of the side support portion, i.e., a position where the upper body of an occupant is supported thereby.

On the other hand, JP63-033849U discloses a seat apparatus for a vehicle including a pressure sensor provided at a side support portion for detecting the physique of an occupant. A support position of the side support portion, i.e., a position where the upper body of an occupant is supported thereby, can be adjusted on the basis of a pressure value detected by the pressure sensor. The support position of the side support portion can be changed depending on the physique of an occupant.

According to the seat apparatus disclosed in JP63-033849U, however, the side support portion should be brought to a closed position at a time the physique of an occupant is being detected by means of the pressure sensor, which may give an oppressive feeling to the occupant. Further, the side support portion should be opened or closed to obtain an appropriate position after the physique of the occupant is detected with the side support portion in the closed state, thereby requiring time.

Thus, a need exits for a seat apparatus for a vehicle which is not susceptible to the drawback mentioned above.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, a seat apparatus for a vehicle including a side support portion that is controlled to be opened and closed depending on a road shape includes a position detecting portion for detecting a position of the side support portion, a sensor provided at the side support portion and detecting a physique of an occupant, a physique detecting portion for detecting the physique of the occupant by means of the sensor while the side support portion is in a full open position, and an initial position determining portion for determining an initial position of the side support portion depending on the physique of the occupant detected by the physique detecting portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and additional features and characteristics of the present invention will become more apparent from the following detailed description considered with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a seat apparatus for a vehicle according to an embodiment of the present invention;

FIG. 2 is a plan view of the seat apparatus according to the embodiment of the present invention;

FIG. 3 is a diagram illustrating a capacitance sensor according to the embodiment of the present invention;

FIG. 4 is an electric connection diagram of the seat apparatus according to the embodiment of the present invention;

FIG. 5 is a diagram illustrating an output pulse of support position sensors according to the embodiment of the present invention;

FIG. 6 is a flowchart illustrating an initial position setting program according to the embodiment of the present invention; and

FIGS. 7A and 7B are each diagram illustrating a relationship between the number of pulses and an initial position according to the embodiment of the present invention.

DETAILED DESCRIPTION

An embodiment of a seat apparatus for a vehicle (hereinafter referred to as a seat apparatus) related to the present invention will be described in accordance with the attached drawings. As illustrated in FIG. 1, the seat apparatus includes a seat slide device 10 and a seat 13. The seat slide device 10 includes, for example, a pair of lower rails 11 and a pair of upper rails 12 supported by the lower rails 11 so as to be slidable thereon. The lower rails 11 are fixed on a floor 90 so as to extend in a front-rear direction of the vehicle. Specifically, the seat 13 includes a seat cushion 14 on which an occupant is seated, and a seat back 15 that supports the occupant's back. Further, a right side support portion 16 and a left side support portion 17 are provided at right and left portions of the seat back 15, respectively, for stabilizing a posture of the occupant by pressing the upper body of the occupant on its sides. Additionally, as illustrated in FIG. 1, a right motor 26 and a left motor 27 are provided at right and left portions of a seat frame 18, respectively. Each of the right and left motors 26 and 27 includes a reduction mechanism. Furthermore, a right support frame 16a and a left support frame 17a are adapted to be pivoted by means of the right and left motors 26 and 27, respectively. Both right and left support frames 16a and 17a are pivoted by both right and left motors 26 and 27 being activated, and therefore the right and left side support portions 16 and 17 are moved to be in an open position, which is indicated with a solid line, and to be in a closed position, which is indicated with a chain double-dashed line illustrated in FIG. 2. Furthermore, as illustrated in FIG. 1, a belt anchor 9 including a buckle 8 is fixed to a rear end portion of one of the upper rails 12. The buckle 8 accommodates a seatbelt sensor 22 that detects whether or not the seatbelt is fastened (i.e., buckled). The right side support portion 16 and the left side support portion 17 collectively serve as a side support portion.

Specifically, each of the side support portions 16 and 17 includes a fixed portion and a movable portion. The respective movable portions of the side support portions 16 and 17 are pivoted in response to activation of the right and left motors 26 and 27, respectively. Then, a right sensor electrode 24a and a left sensor electrode 24b are arranged at the respective movable portions of the side support portions 16 and 17 so as to form a part of a capacitance sensor 24. Precisely, as illustrated in FIG. 3, the capacitance sensor 24 is provided for measuring a capacitance formed between the sensor electrodes 24a and 24b, and an occupant, and a capacitance formed between the occupant and a sensor ground 24c connected to a chassis so as to detect the physique of the occupant. The capacitance sensor 24 serves as a sensor.

FIG. 4 illustrates an electric connection diagram of the seat apparatus. As illustrated in FIG. 4, the seat apparatus includes a physique detection ECU 20 and a side support ECU 21. The seatbelt sensor 22 and the capacitance sensor 24 are connected to the physique detection ECU 20. The seatbelt sensor 22 detects whether or not the seatbelt is fastened, (i.e., buckled) and then outputs a signal indicating the detection result, i.e., seatbelt status signal, to the physique detection ECU 20. In addition, the capacitance sensor 24 measures the physique of an occupant as mentioned above.

The right motor 26, the left motor 27, a right position sensor 28, and a left position sensor 29 are all connected to the side support ECU 21. The side support ECU 21 outputs driving signals to both the right and left motors 26 and 27, and inputs pulse signals serving as position signals from both the position sensors 28 and 29. The side support ECU 21 and the physique detection ECU 20 are connected to each other so that information can be shared and transmitted therebetween.

As illustrated in FIG. 5, the right and left position sensors 28 and 29 each output, for example, 0 to 300 pulses depending on the position of the side support portions 16 and 17 within a range from a full closed position to a full open position. The side support ECU 21 monitors and calculates the output pulses from the position sensors 28 and 29 to thereby detect the position of the side support portions 16 and 17.

A process for setting an initial position of the side support portions 16 and 17 according to the aforementioned seat apparatus will be explained below. A ROM in the physique detection ECU 20 stores an initial position setting program as illustrated in FIG. 6 conducted per predetermined time interval.

In the cases where the initial position setting program illustrated in FIG. 6 is started, the physique detection ECU 20 obtains various information in step S10. Precisely, the physique detection ECU 20 inputs a signal indicating whether or not the seatbelt is fastened (i.e., seatbelt status signal) from the seatbelt sensor 22 and position information of the side support portions 16 and 17 from the side support ECU 21. That is, at this time, the side support ECU 21 is conducting a side support control program (not shown) so as to obtain position information of the side support portions 16 and 17 based on the pulse signals input from the position sensors 28 and 29. Then, the physique detection ECU 20 inputs the position information of the side support portions 16 and 17 from the side support ECU21. The step S10, the right position sensor 28, and the left position sensor 29 collectively serve as a position detecting portion.

In step S11, the physique detection ECU 20 determines whether or not a trigger signal for the physique detection is present. In the cases where the trigger signal is present (i.e., YES as indicated by “Y” in FIG. 6), a process in step S12 is then performed. In the cases where the trigger signal is not present (i.e., NO as indicated by “N” in FIG. 6), the execution of the initial position setting program is terminated. As the trigger signal, the seatbelt status signal from the seatbelt sensor 22 is used. Only in the cases where the seatbelt is fastened for the first time from a state where the seatbelt is not fastened, it is determined that the trigger signal is present. Accordingly, in the cases where the seatbelt is not fastened or the seatbelt is already fastened, it is determined that the trigger signal is not present. Alternatively, as the trigger signal for the physique detection, a drive range switch signal of a shift lever may be used. That is, it is determined that the trigger signal is present only when the shift lever is shifted to the drive range for the first time after the ignition switch is turned on.

In step S12, the physique detection ECU 20 determines whether or not the side support portions 16 and 17 are in the full open position. When it is determined that the side support portions 16 and 17 are in the full open position (i.e., YES), a process in step S13 is then performed. On the other hand, when it is determined that the side support portions 16 and 17 are not in the open position (i.e., NO), the execution of the initial position setting program is terminated. At this time, whether or not the side support portions 16 and 17 are in the full open position is determined through the position information of the side support portions 16 and 17 input from the side support ECU 21 in the step S10.

In step S13, the physique detection ECU 20 detects the physique of an occupant by means of the capacitance sensor 24. In step S14, the physique detection ECU 20 obtains initial position information of the side support portions 16 and 17 based on the detected physique by using a table prepared beforehand, and then outputs that initial position information to the side support ECU21. The physique detection ECU 20 terminates the initial position setting program after executing the process in step S14. At this time, according to the present embodiment, the initial position information is obtained by means of the table prepared beforehand. Alternatively, the initial position information may be obtained by calculation. The initial position of the side support portions 16 and 17 is defined to be on a slightly full open side of a support position where the upper body of an occupant is pressed from both sides so as to support and stabilize a sitting posture of the occupant. That is, the initial position is defined to be a position where the side support portions 16 and 17 can be immediately activated to the support position. In addition, the initial position information is equal to the number of pulses outputted from the position sensors 28 and 29 while the side support portions 16 and 17 are controlled to be closed from the full open position to reach the initial position by the side support ECU 21. The step S13 serves as a physique detecting portion, and the step S14 serves as an initial position determining portion.

Then, the side support ECU 21 outputs the driving signals to the right and left motors 26 and 27 based on the initial position information so that the side support portions 16 and 17 are specified to be in the initial position. When a vehicle starts driving, the side support portions 16 and 17 are controlled to be opened and closed by the side support ECU 21 in response to the lateral acceleration of the vehicle within a range between the initial position and the support position.

Next, an application example of the initial position setting program will be explained with reference to FIGS. 7A and 7B. FIG. 7A illustrates an example in which an occupant having obese physique is seated while FIG. 7B illustrates an example in which an occupant having slim physique is seated. In both examples illustrated in FIGS. 7A and 7B, the support position where the upper body of the occupant is pressed from both sides so as to support a sitting posture of the occupant is defined to be a range of 150 pulses that are outputted from the position sensors 28 and 29 as illustrated by arrows in FIGS. 7A and 7B. In addition, 30 pulses are defined between the initial position and one end of the support position close to the full open position.

In the cases where the occupant sits down on the seat cushion 14 and fastens the seatbelt, it is determined that the trigger signal for the physique detection is present in the step S11. Then, when the side support portions 16 and 17 are in the full open position at that time, the physique of the occupant is detected in the step S13. Further, in the step S14, the number of pulses generated in response to the occupant's physique is obtained as initial position information that is then input to the side support ECU 21. The number of pulses as the initial position information is sixty in the example illustrated in FIG. 7A or ninety in the example illustrated in FIG. 7B.

Meanwhile, the side support ECU 21, which is executing the side support control program, controls the side support portions 16 and 17 to be in the initial position based on the initial position information input from the physique detection ECU 20. When the vehicle starts driving, the side support portions 16 and 17 are controlled to be opened and closed by the side support ECU 21 in response to the lateral acceleration within the range between the initial position and the support position.

According to the aforementioned seat apparatus, the initial position of the side support portions 16 and 17 is determined in the step S14 based on the physique of the occupant detected in the step S13. On the basis of the initial position determined, the side support portions 16 and 17 are controlled to be opened and closed depending on a road shape. Further, in the step S13, the physique of the occupant is detected while the side support portions 16 and 17 are in the full open state. That is, the side support portions 16 and 17 are not required to be closed at a time of detecting the occupant's physique. Thus, according to the present seat apparatus, the support position can be changed in response to difference in the physique of an occupant. In addition, the physique of an occupant can be detected within a short time period without adding an oppressive feeling to the occupant.

In addition, according to the aforementioned seat apparatus, the capacitance sensor 24, precisely, the sensor electrodes 24a and 24b, is provided at the movable portions of the side support portions 16 and 17 to thereby appropriately detect the physique of an occupant. Further, since the physique of an occupant is detected at a time the occupant fastens the seatbelt, the physique substantially same as that in the vehicle driving state can be detected.

Further, according to the aforementioned embodiment, since the capacitance sensor 24 is provided for the physique detection, the physique of an occupant can be detected while the right and left side support portions 16 and 17 are in the full open position.

Furthermore, according to the aforementioned embodiment, the capacitance sensor 24 is provided at a movable portion of the side support portion 16 or 17.

Furthermore, according to the aforementioned embodiment, the physique of the occupant is detected by the position sensors 28 and 29, and through the step S14 in a case where the occupant fastens a seatbelt.

Furthermore, according to the aforementioned embodiment, the physique of the occupant is detected by the position sensors 28 and 29, and through the step S14 in a case where a shift lever is shifted to a drive range.

The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby.

Claims

1. A seat apparatus for a vehicle including a side support portion that is controlled to be opened and closed depending on a road shape, comprising:

a position detecting portion for detecting a position of the side support portion;

a sensor provided at the side support portion and detecting a physique of an occupant;

a physique detecting portion for detecting the physique of the occupant by means of the sensor while the side support portion is in a full open position; and

an initial position determining portion for determining an initial position of the side support portion depending on the physique of the occupant detected by the physique detecting portion.

2. A seat apparatus according to claim 1, wherein the sensor is equal to a capacitance sensor.

3. A seat apparatus according to claim 1, wherein the sensor is provided at a movable portion of the side support portion.

4. A seat apparatus according to claim 2, wherein the sensor is provided at a movable portion of the side support portion.

5. A seat apparatus according to claim 1, wherein the physique detecting portion detects the physique of the occupant in a case where the occupant fastens a seatbelt.

6. A seat apparatus according to claim 2, wherein the physique detecting portion detects the physique of the occupant in a case where the occupant fastens a seatbelt.

7. A seat apparatus according to claim 3, wherein the physique detecting portion detects the physique of the occupant in a case where the occupant fastens a seatbelt.

8. A seat apparatus according to claim 4, wherein the physique detecting portion detects the physique of the occupant in a case where the occupant fastens a seatbelt.

9. A seat apparatus according to claim 1, wherein the physique detecting portion detects the physique of the occupant in a case where a shift lever is shifted to a drive range.

10. A seat apparatus according to claim 2, wherein the physique detecting portion detects the physique of the occupant in a case where a shift lever is shifted to a drive range.

11. A seat apparatus according to claim 3, wherein the physique detecting portion detects the physique of the occupant in a case where a shift lever is shifted to a drive range.

12. A seat apparatus according to claim 4, wherein the physique detecting portion detects the physique of the occupant in a case where a shift lever is shifted to a drive range.