Vehicular seat

Abstract

To provide a vehicular seat that can suppress a specific part of a user from being continuously pressed comparatively strongly.SOLUTION: A vehicular seat 1 is provided on a vehicle V. The vehicular seat 1 comprises: a seating face angle change actuator 10 that changes a seating face angle θ which is an angle formed by a reference surface R set on a floor 3 and a seat cushion 4; a seating sensor 20 provided on the seat cushion 4; and a control device 16 that is connected to the seating sensor 20 and the seating face angle change actuator 10 and controls the seating face angle change actuator 10. The control device 16 calculates cumulative seating times elapsing from a time point when a user is seated until now, on the basis of output of the seating sensor 20, and when the calculated cumulative seating times are above a predetermined increase / decrease starting time, executes increase / decrease processing for increasing or decreasing the seating face angle θ.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a vehicle seat.

Background Art

[0002] There are various vehicle seats that can be deformed so that a user can sit comfortably. For example, Patent Document 1 describes a vehicle seat capable of changing the inclination of the seating surface of a seat cushion from a front-lower state where the front part of the seating surface of the seat cushion is lower than the rear part to a front-upper state where the front part of the seating surface is higher than the rear part.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a user sits on a seat cushion, there are parts such as the user's buttocks that are relatively strongly pressed. When the user continues to sit on the vehicle seat for a long time, poor blood circulation is likely to occur in the parts of the user that are relatively strongly pressed. It is desired to suppress the occurrence of poor blood circulation in the user.

[0005] In view of the above background, an object of the present invention is to provide a vehicle seat capable of suppressing continuous relatively strong pressing of a specific part of a user.

Means for Solving the Problems

[0006] In order to solve the above problems, one aspect of the present invention is a vehicle seat (1) provided on a floor (3) of a vehicle (V), having a seat cushion (4) that supports a user's buttocks from below, the vehicle seat including a seat surface angle changing actuator (10) that changes a seat surface angle (θ), which is an angle formed between a reference plane (R) set with respect to the floor and the seat cushion, a seating sensor (20) provided on the seat cushion, and a control device (16) connected to the seating sensor and the seat surface angle changing actuator to control the seat surface angle changing actuator. The control device calculates a cumulative seating time from the time when the user sits until the present based on an output of the seating sensor, and when the calculated cumulative seating time is equal to or more than a predetermined increase / decrease start time, executes an increase / decrease process of increasing or decreasing the seat surface angle.

[0007] According to this aspect, it is possible to suppress a situation where a specific part of the user is continuously pressed relatively strongly.

[0008] In the above aspect, the control device may change the increase / decrease start time according to the seat surface angle.

[0009] According to this aspect, it is possible to more appropriately suppress a situation where a specific part of the user is continuously pressed relatively strongly.

[0010] In the above aspect, the control device can change the seat surface angle within a range from a maximum angle larger than a standard seat surface angle, which is the standard of the seat surface angle, to a minimum angle smaller than the standard seat surface angle. When the seat surface angle is larger than the standard seat surface angle, the increase / decrease start time is set to a predetermined first increase / decrease start time, and when the seat surface angle is equal to or less than the standard seat surface angle, the increase / decrease start time is set to a predetermined second increase / decrease start time. The first increase / decrease start time may be shorter than the second increase / decrease start time.

[0011] According to this aspect, it is possible to more appropriately suppress a situation where a specific part of the user is continuously pressed relatively strongly.

[0012] In the above aspect, it is preferable that the control device sets the increase / decrease start time to a shorter time as the seat surface angle is larger.

[0013] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0014] In the above aspect, it is preferable that the increase / decrease process is a process of generating vibrations in which the seat surface angle increases and decreases at a predetermined vibration cycle.

[0015] According to this aspect, it is possible to continuously suppress the continuous relatively strong compression of a specific part of the user.

[0016] In the above aspect, it is preferable that the control device sets the vibration cycle according to the seat surface angle.

[0017] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0018] In the above aspect, the control device can change the seat surface angle within a range from a maximum angle larger than a standard seat surface angle which is the standard of the seat surface angle to a minimum angle smaller than the standard seat surface angle. When the seat surface angle is larger than the standard seat surface angle, the vibration cycle is set to a predetermined first vibration cycle, and when the seat surface angle is less than or equal to the standard seat surface angle, the vibration cycle is set to a predetermined second vibration cycle, and it is preferable that the first vibration cycle is shorter than the second vibration cycle.

[0019] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0020] In the above aspect, it is preferable that the control device shortens the vibration cycle as the seat surface angle is larger.

[0021] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0022] In the above aspect, the control device is connected to a vehicle state monitoring device that monitors the turning of the vehicle. When it is determined that the vehicle is turning based on the output of the vehicle state monitoring device, the change in the seat surface angle may be suppressed.

[0023] According to this aspect, the user can cope with the turning of the vehicle without paying attention to the change in the seat surface angle θ.

[0024] In the above aspect, the seat surface angle changing actuator is provided on each of the left and right portions of the seat cushion. The control device can change the left seat surface angle of the left portion of the seat cushion and the right seat surface angle of the right portion of the seat cushion to different angles from each other. The increase / decrease process may include a process of changing the left seat surface angle and the right seat surface angle to different angles from each other.

[0025] According to this aspect, it is possible to more effectively suppress the continuous relatively strong compression of a specific part of the user.

Effect of the Invention

[0026] In order to solve the above problems, one aspect of the present invention is a vehicle seat (1) provided on a floor (3) of a vehicle (V), having a seat cushion (4) that supports a user's buttocks from below, the vehicle seat including: a seat surface angle changing actuator (10) that changes a seat surface angle (θ), which is an angle formed between a reference surface (R) set with respect to the floor and the seat cushion; a seating sensor (20) provided on the seat cushion; and a control device (16) connected to the seating sensor and the seat surface angle changing actuator, and controlling the seat surface angle changing actuator. The control device calculates a cumulative seating time from the time when the user sits until the present based on the output of the seating sensor, and when the calculated cumulative seating time is equal to or more than a predetermined increase / decrease start time, executes an increase / decrease process of increasing or decreasing the seat surface angle.

[0027] According to this aspect, it is possible to suppress a specific part of the user from being continuously pressed relatively strongly.

[0028] In the above aspect, the control device may change the start time of the increase and decrease according to the seat surface angle.

[0029] According to this aspect, it is possible to more appropriately suppress a specific part of the user from being continuously pressed relatively strongly.

[0030] In the above aspect, the control device can change the seat surface angle in a range from a maximum angle greater than a standard seat surface angle which is the standard of the seat surface angle to a minimum angle smaller than the standard seat surface angle. When the seat surface angle is greater than the standard seat surface angle, the start time of the increase and decrease is set to a predetermined first start time of increase and decrease. When the seat surface angle is less than or equal to the standard seat surface angle, the start time of the increase and decrease is set to a predetermined second start time of increase and decrease. The first start time of the increase and decrease may be shorter than the second start time of the increase and decrease.

[0031] According to this aspect, it is possible to more appropriately suppress a specific part of the user from being continuously pressed relatively strongly.

[0032] In the above aspect, the control device may set the start time of the increase and decrease to a shorter time as the seat surface angle is larger.

[0033] According to this aspect, it is possible to more appropriately suppress a specific part of the user from being continuously pressed relatively strongly.

[0034] In the above aspect, the increase and decrease process may be a process of generating vibrations in which the seat surface angle increases and decreases at a predetermined vibration cycle.

[0035] According to this aspect, it is possible to continuously suppress a specific part of the user from being continuously pressed relatively strongly.

[0036] In the above aspect, the control device may set the vibration cycle according to the seat surface angle.

[0037] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0038] In the above aspect, the control device can change the seat surface angle in a range from a maximum angle greater than a standard seat surface angle which is the standard of the seat surface angle to a minimum angle smaller than the standard seat surface angle. When the seat surface angle is greater than the standard seat surface angle, the vibration period is set to a predetermined first vibration period, and when the seat surface angle is less than or equal to the standard seat surface angle, the vibration period is set to a predetermined second vibration period. It is preferable that the first vibration period is shorter than the second vibration period.

[0039] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0040] In the above aspect, it is preferable that the control device shortens the vibration period as the seat surface angle increases.

[0041] According to this aspect, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0042] In the above aspect, the control device is connected to a vehicle state monitoring device that monitors the turning of the vehicle. When it is determined based on the output of the vehicle state monitoring device that the vehicle is turning, it is preferable to suppress the change of the seat surface angle.

[0043] According to this aspect, the user can respond to the turning of the vehicle without paying attention to the change of the seat surface angle θ.

[0044] In the above aspect, the seat surface angle changing actuator is provided at each of the left and right portions of the seat cushion, and the control device can change the left seat surface angle of the left portion of the seat cushion and the right seat surface angle of the right portion of the seat cushion to different angles from each other, and the increasing and decreasing process preferably includes a process of changing the left seat surface angle and the right seat surface angle to different angles from each other.

[0045] According to this aspect, it is possible to more effectively suppress the continuous relatively strong compression of a specific part of the user.

Brief Description of the Drawings

[0046]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0047] Hereinafter, with reference to the drawings, the vehicle seat 1 according to an embodiment of the present invention will be described. FIG. 1 shows a deformed state of the vehicle seat 1, FIG. 2 shows the configuration of a vehicle V equipped with the vehicle seat 1, and FIG. 3 is a block diagram of a system 2 related to the vehicle seat 1. In the following description, unless otherwise specified, the "front-rear direction", "left-right direction", and "up-down direction" mean the front-rear direction, left-right direction, and up-down direction of the vehicle V. Also, a direction based on the vehicle seat 1, such as the "front-rear direction of the seat", means the direction as seen from a user sitting on the vehicle seat 1.

[0048] <<First Embodiment>> As shown in FIGS. 1 and 2, the vehicle seat 1 is installed on the floor 3 in the passenger compartment of the vehicle V. The vehicle seat 1 includes a seat cushion 4, a seat back 5 supported at the rear of the seat cushion 4, and a headrest 6 connected to the upper part of the seat back 5. The seat cushion 4 supports the user's buttocks from below, the seat back 5 supports the user's back from the rear in the front-rear direction of the seat, and the headrest 6 supports the user's head from the rear in the front-rear direction of the seat. The seat cushion 4 and the seat back 5 each include a frame, a pad supported by the frame, and a skin material covering the surface of the pad on the user side (not shown).

[0049] A rotating device 8 is supported on the floor 3 via a sliding device 7. The rotating device 8 rotatably supports a support member 9 with respect to the sliding device 7 around a vertical axis Z passing through substantially the center in the front-rear direction and the seat width direction of the seat. The front end of the seat cushion 4 or the vicinity thereof is tiltably connected to the front end of the support member 9 around a tilting axis Y1 in the seat width direction. A seat surface angle changing actuator 10 that can expand and contract in its extending direction is pivotally connected at one end to a position below and / or behind the seat with respect to the tilting axis Y1 of the support member 9, and at the other end to a position behind the seat of the seat cushion 4, around an axis in the seat width direction. As the seat surface angle changing actuator 10, an electric cylinder, an air cylinder, or a hydraulic cylinder having a motor may be used.

[0050] The angle that varies around the tilting axis Y1 formed by the reference plane R (floor surface) orthogonal to the vertical direction and the seating surface S of the seat cushion 4 is defined as the seating surface angle θ (thigh angle). The support member 9 and the seating surface angle changing actuator 10 constitute the main part of the seating surface angle changing device 11 that changes the seating surface angle θ. Since the seating surface S deforms during actual seating, strictly speaking, it is set with reference to the seat frame. When viewed from the side of the seat, the three points of the tilting axis Y1 and the two rotatable connection points of the seating surface angle changing actuator 10 to the support member 9 and the seat cushion 4 are not arranged on the same straight line, that is, they are arranged to form the vertices of a triangle. Therefore, when the seating surface angle changing actuator 10 expands and contracts, the seating surface angle θ is changed. The seating surface angle changing device 11 can tilt the seat cushion 4 around the tilting axis Y1 between a state where the front end of the seating surface S is tilted downward with respect to the reference plane R (the state where the seating surface angle θ is negative, see Fig. 1(A)) and a state where the front end of the seating surface S is tilted upward with respect to the reference plane R (the state where the seating surface angle θ is positive, see Fig. 1(C)).

[0051] In the illustrated example, the tilting axis Y1 is arranged at the front end of the seat cushion 4, but the tilting axis Y1 may be arranged at any position from the front end to the rear end of the seat cushion 4, and the seating surface angle changing device 11 may have a configuration that allows the seat cushion 4 to tilt with respect to the reference plane R.

[0052] As shown in Figs. 2 and 3, the system 2 includes an in-vehicle monitoring device 12 that acquires information inside the vehicle cabin, an out-of-vehicle monitoring device 13 that acquires information outside the vehicle, an input / output device 14 that receives and provides information to the user, a vehicle state monitoring device 15 that acquires information regarding the state of the vehicle V, a control device 16 that receives information from the in-vehicle monitoring device 12, the out-of-vehicle monitoring device 13, the input / output device 14, and the vehicle state monitoring device 15 and transmits the information to the input / output device 14, and a plurality of controlled devices 17 controlled by the control device 16.

[0053] The in-vehicle monitoring device 12 includes one or more in-vehicle cameras 18 that image the interior of the vehicle, a plurality of object sensors 19 provided on the vehicle seat 1, a seating sensor 20 provided on the seat cushion 4, a biological sensor 21, and a seat surface angle sensor 22.

[0054] The in-vehicle camera 18 is disposed at a position where it can image the user and the periphery of the vehicle seat 1. The in-vehicle camera 18 may be constituted by a CMOS image sensor. The in-vehicle camera 18 is preferably constituted by a compound eye camera including a plurality of imaging elements, and is capable of distance imaging based on triangulation such as stereo measurement or light section method.

[0055] The object sensor 19 is a sensor that detects objects inside the vehicle, and may be a proximity sensor, a lidar, an ultrasonic sensor, or the like. Alternatively, the object sensor 19 may be constituted by a ToF (Time of Flight) sensor module that includes a light source and a detector and performs distance measurement by acquiring the time until the light emitted from the light source reaches the detector. The object sensor 19 may be disposed, for example, along the outer peripheral surface of the seat cushion 4, or may be provided at an appropriate position of the headrest 6. Further, the object sensors 19 may be arranged side by side in the front-rear direction on the door panel or the floor 3.

[0056] The seating sensor 20 may be a membrane switch or an electrostatic sensor provided on the seat cushion 4. The seating sensor 20 detects the pressure applied to the seat cushion 4, and the control device 16 that has received the detection result determines whether the user is seated on the vehicle seat 1. A seat belt reminder (SBR) system that issues an alarm when the user is seated on the vehicle seat 1 but not wearing the seat belt is adopted, and the seating determination using the seating sensor 20 is performed to determine whether an alarm is necessary.

[0057] The biological sensor 21 may be a heartbeat sensor, a respiration sensor, a pressure sensor, or an electroencephalogram sensor. The heartbeat sensor is provided on the front surface of the seat back 5 and is preferably disposed at a position corresponding to the user's heart. The heartbeat sensor is a sensor that detects the user's heart rate. The heartbeat sensor may be based on any of a touch type, an optical type, or an electrocardiogram type. The respiration sensor is a sensor that detects the user's respiration rate and the depth of respiration. The respiration sensor may be of a type that, for example, detects the pressure applied from the user at a position corresponding to the user's lungs on the front surface of the seat back 5 and reads the pressure change caused by the user's respiratory movement. The respiration sensor may be based on a method in which two sheet-like electrodes are provided along the front surface of the seat back 5 and the change in capacitance between the electrodes due to the movement of the user's chest is detected. The pressure sensor is a sensor used to detect the user's posture based on the pressure applied to the seat cushion 4 and the seat back 5. The pressure sensor is provided in a planar shape on the surfaces of the seat cushion 4 and the seat back 5 facing the user, measures the in-plane distribution (pressure distribution) of the pressure applied from the user to them, and detects the user's posture. The electroencephalogram sensor includes a magnetic sensor provided at a position facing the user's head in the headrest 6. The magnetic sensor detects the magnetic signal associated with the activity of the user's brain cells. The electroencephalogram sensor calculates the user's electroencephalogram based on the magnetic signal. As the electroencephalogram sensor, a magnetic sensor provided at a position facing the user's head in the headrest 6 may be used, and the control device 16 may calculate the user's electroencephalogram based on the magnetic signal.

[0058] The seat surface angle sensor 22 is provided between the support member 9 and the frame of the seat cushion 4 or in the seat surface angle changing actuator 10, and detects the seat surface angle θ (see FIG. 1) or information for calculating the seat surface angle θ.

[0059] The outside vehicle monitoring device 13 includes one or more outside vehicle photographing cameras 23 and a plurality of radars 24 and / or lidars 25 (LiDAR).

[0060] The outside vehicle camera 23 images the surroundings of the vehicle V, including objects existing around the vehicle V (for example, surrounding vehicles and pedestrians), guardrails, curbs, walls, median strips, the shape of the road, road markings drawn on the road, and the like. The outside vehicle camera 23 may be, for example, a digital camera using a solid-state imaging device such as a CCD or a CMOS. The outside vehicle camera 23 is provided, for example, on the ceiling inside the vehicle compartment and images the outside of the vehicle compartment through the windshield, rear glass, or side glass. The outside vehicle camera 23 may be, for example, a stereo camera.

[0061] The radar 24 emits radio waves such as millimeter waves around the vehicle V and detects the position (distance and direction) of an object by capturing the reflected wave. The lidar 25 irradiates light such as infrared rays around the vehicle V and detects the position (distance and direction) of an object by capturing the reflected light. The radar 24 and / or the lidar 25 are attached outside the vehicle compartment of the vehicle V. The radar 24 and / or the lidar 25 include, for example, those that irradiate radio waves / light forward of the vehicle V, those that irradiate radio waves / light rearward of the vehicle V, and those that irradiate radio waves / light laterally of the vehicle V. The outside vehicle compartment monitoring device 13 may include a sonar.

[0062] The input / output device 14 receives an input operation by the user and notifies the user of various information by display or sound. The input / output device 14 may include, for example, a touch panel 26 that performs both input and output. In addition to or instead of the touch panel 26, the input / output device 14 may include an input device (for example, buttons, switches, and / or a microphone 27 that receives the user's voice input) and an output device (for example, a display and / or a speaker 28 that notifies sound). A mobile terminal such as a smartphone may be communicable with the control device 16 wirelessly or wiredly and used as the input / output device 14.

[0063] The vehicle state monitoring device 15 includes a vehicle speed sensor 29, a brake sensor 30, a steering angle sensor 31, a shift lever sensor 32, and a door sensor 33. The vehicle speed sensor 29 detects the vehicle speed of the vehicle V. The brake sensor 30 includes a brake pedal sensor that detects the depression amount of the brake pedal and a parking brake sensor that detects the operation amount of the parking brake lever. The steering angle sensor 31 detects the steering angle of the steering wheel. The shift lever sensor 32 detects where the shift lever is placed, such as in parking (P), reverse (R), neutral (N), drive (D), etc. The door sensor 33 detects the open / closed state of the door of the vehicle V.

[0064] The control device 16 is a so-called Electronic Control Unit, which controls the vehicle seat 1 based on the information acquired by the in-vehicle monitoring device 12, the out-vehicle monitoring device 13, and the vehicle state monitoring device 15, as well as the information input by the user to the input / output device 14. The control device 16 is composed of a computer including a processor 34 constituted by a CPU (Central Processing Unit) etc., a storage device 35 including a RAM (Random Access Memory), a ROM (Read Only Memory), and an SSD (Solid State Drive) and / or an HDD (Hard Disk Drive). The control device 16 is connected to the in-vehicle monitoring device 12, the out-vehicle monitoring device 13, the input / output device 14, the vehicle state monitoring device 15, and the device to be controlled 17 so that signals can be transmitted and received by signal lines or wirelessly. The control device 16 and the device to be controlled 17 are connected to a power source (not shown) mounted on the vehicle V and receive power supply from the power source. The control device 16 can acquire information regarding the vehicle seat 1, such as the state of the seat surface angle θ (see FIG. 1), based on the information acquired by the in-vehicle monitoring device 12 and the control history for the device to be controlled 17.

[0065] The controlled device 17 controlled by the control device 16 includes, in addition to the above-described slide device 7, rotation device 8, and seat surface angle changing device 11, a reclining device 36 that tilts the seat back 5, an airbag device 37 that protects the user during a collision of the vehicle V, a side support device 38 that changes the height of both side portions of the seat cushion 4, a seat heater 39 that warms the seat cushion 4, and a vibration device 40 that vibrates the seat cushion 4 to prompt the user's attention.

[0066] The control device 16 can calculate the seat surface angle θ from the detection value of the seat surface angle sensor 22. The seat surface angle sensor 22 may be, for example, an angle potentiometer provided between the support member 9 and the seat cushion 4. Further, the seat surface angle sensor 22 may be a stroke sensor that detects the length of the seat surface angle changing actuator 10, and the control device 16 may calculate the seat surface angle θ based on the length of the seat surface angle changing actuator 10. The control device 16 may also calculate the seat surface angle θ from the control history of the seat surface angle changing actuator 10.

[0067] The user can change the seat surface angle θ by operating the input / output device 14. The input / output device 14 outputs an operation signal corresponding to the user's operation to the control device 16. The control device 16 controls the seat surface angle changing actuator 10 based on the operation signal to change the seat surface angle θ to an angle within the changeable range. The changeable range is the range of angles in which the seat surface angle θ can be changed, and is defined by the minimum angle (see FIG. 1(A)) and the maximum angle (see FIG. 1(C)). The changeable range is set by the control device 16.

[0068] The reclining device 36 is a device that tilts the seat back 5 with respect to the seat cushion 4 around a tilting axis Y2 (see FIG. 1) extending in the seat width direction. The tilting axis Y2 extends to the rear end in the front-rear direction of the seat of the seat cushion 4 and the lower end of the seat back 5.

[0069] The vehicle seat 1 of the present embodiment suppresses a situation where a specific part of the seated user continues to be relatively strongly pressed by changing the seat surface angle θ.

[0070] When the control device 16 determines that the user is seated on the vehicle seat 1 based on the detection result of the seating sensor 20, it executes cumulative seating time calculation processing, seating determination processing, and increase / decrease start determination processing. In the cumulative seating time calculation processing, the control device 16 calculates the cumulative seating time from the time when the user sat down to the present. While executing the cumulative seating time calculation processing, the control device 16 starts the execution of the increase / decrease start determination processing at predetermined time intervals (for example, every 10 seconds). The increase / decrease start determination processing includes increase / decrease processing. When the increase / decrease processing is being executed, the execution of the increase / decrease start determination processing is not started at predetermined time intervals.

[0071] The seating determination processing is a process for stopping the execution of the cumulative seating time calculation processing and the increase / decrease start determination processing when the user is not seated. In the seating determination processing, the control device 16 acquires the detection result of the seating sensor 20 at predetermined time intervals (for example, every 1 second). When the time during which it can be determined that the user is not seated continues for a seating determination time threshold value (for example, 30 seconds) or more, the seating flag is set to 1 (seating flag = 1). The seating flag being 1 (seating flag = 1) indicates that the user is not seated. When the control device 16 sets the seating flag to 1, it stops the ongoing cumulative seating time calculation processing and the ongoing increase / decrease start determination processing (increase / decrease processing). Then, the control device 16 resets the seating flag to 0.

[0072] When the vehicle (automobile) V is turning, in order to temporarily stop the ongoing increase / decrease start determination process (increase / decrease process), the control device 16 performs the following turning determination process. In the turning determination process, the control device 16 determines whether the vehicle (automobile) V is turning based on the steering angle of the steering wheel detected by the steering angle sensor 31 (vehicle state monitoring device 15). When the control device 16 determines that the vehicle (automobile) V is turning, it sets the seating flag to 2 (seating flag = 2). When the control device 16 sets the seating flag to 2, it temporarily stops the ongoing cumulative seating time calculation process and the ongoing increase / decrease start determination process (increase / decrease process). After that, when the control device 16 determines that the vehicle (automobile) V is not turning, it sets the seating flag to 0 (seating flag = 0) and resumes the execution of the temporarily stopped cumulative seating time calculation process and increase / decrease start determination process (increase / decrease process). Hereinafter, with reference to FIG. 4, the details of the increase / decrease start determination process will be described.

[0073] As shown in FIG. 4, in the first step ST1 of the increase / decrease start determination process, the control device 16 calculates the increase / decrease start time ts based on the seat surface angle θ. The control device 16 changes the seat surface angle θ within a range from the maximum angle (see FIG. 1(C)) greater than the standard seat surface angle (see FIG. 1(B)), which is the standard seat surface angle, to the minimum angle (see FIG. 1(A)) smaller than the standard seat surface angle, in response to the operation of the user input / output device 14. When the seat surface angle θ is greater than the standard seat surface angle (standard seat surface angle < seat surface angle θ), the control device 16 sets the increase / decrease start time ts to a predetermined first increase / decrease start time ts1 (for example, 10 minutes). Also, when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle), the control device 16 sets the increase / decrease start time ts to a predetermined second increase / decrease start time ts2 (for example, 20 minutes). The first increase / decrease start time ts1 is shorter than the second increase / decrease start time ts2 (first increase / decrease start time ts1 < second increase / decrease start time ts2). After calculating the increase / decrease start time ts, the control device 16 executes step ST2.

[0074] In step ST2, the control device 16 determines whether the cumulative seating time is greater than or equal to the increase / decrease start time ts (increase / decrease start time ts ≤ cumulative seating time). If the control device 16 determines that the cumulative seating time is less than the increase / decrease start time ts (cumulative seating time < increase / decrease start time ts), it ends the increase / decrease start determination process. If the control device 16 determines that the cumulative seating time is greater than or equal to the increase / decrease start time ts (increase / decrease start time ts ≤ cumulative seating time), it executes ST3.

[0075] In step ST3, the control device 16 controls the seat surface angle change actuator 10 to execute an increase / decrease process that generates vibrations in which the seat surface angle θ increases and decreases with a predetermined vibration period T. The increase / decrease process is part of the increase / decrease start determination process. When the control device 16 executes the increase / decrease process, it ends the increase / decrease start determination process. Hereinafter, with reference to FIG. 5, the details of the increase / decrease process will be described.

[0076] As shown in FIG. 5, in the increase / decrease process, vibrations Vd in which the seat surface angle θ increases and decreases with a predetermined vibration period T are generated. The vibration Vd is a vibration in which the seat surface angle θ increases and decreases around the seat surface angle θ immediately before the execution of the increase / decrease process (referred to as the "immediate previous seat surface angle θo"). The control device 16 continues to generate the vibration Vd until the user leaves the seat (until the seating flag becomes 1).

[0077] When the seat surface angle θ is greater than the standard seat surface angle (standard seat surface angle < seat surface angle θ), the control device 16 generates a first vibration Vd1 with a predetermined first vibration period T1 in the increase / decrease process. When the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle), the control device 16 generates a second vibration Vd2 with a predetermined second vibration period T2 in the increase / decrease process. The first vibration Vd1 and the second vibration Vd2 are sine waves. The first vibration period T1 is shorter than the second vibration period T2 (first vibration period T1 < second vibration period T2). The magnitude of the amplitude Ad1 of the first vibration Vd1 is the same as the magnitude of the amplitude Ad2 of the second vibration Vd2 (amplitude Ad1 = amplitude Ad2). The control device 16 may make the magnitude of the amplitude Ad1 of the first vibration Vd1 larger than the amplitude Ad2 of the second vibration Vd2.

[0078] According to the present embodiment, when the cumulative sitting time is equal to or longer than the increase / decrease start time (ST2: Yes), the vehicle seat 1 executes an increase / decrease process of increasing or decreasing the seat surface angle θ (ST3). By changing the seat surface angle θ, the orientation of the user's buttocks changes. Thereby, it is possible to suppress a specific part of the user from being continuously pressed relatively strongly.

[0079] The control device 16 changes the increase / decrease start time ts according to the seat surface angle θ (ST1). Depending on the seat surface angle θ, the magnitude of the pressure applied to the portion that is continuously pressed relatively strongly by the user changes. Therefore, it is possible to more appropriately suppress a specific part of the user from being continuously pressed relatively strongly.

[0080] The control device 16 makes the first increase / decrease start time ts1 when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) shorter than the second increase / decrease start time ts2 when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle). As the seat surface angle θ increases, the front end of the seating surface S rises, and the user's knees are lifted upward. And the larger the seat surface angle θ, the easier it is for the user's feet to leave the floor 3, and the weight of the user's feet is more likely to be applied to the knees. Therefore, it can be considered that the pressure applied to the portion that is continuously pressed relatively strongly in the user's thigh increases as the seat surface angle θ increases. For this reason, it can be considered that the pressure applied to the portion that is continuously pressed relatively strongly in the user's thigh is greater when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) than when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle). And the first increase / decrease start time ts1 when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) is shorter than the second increase / decrease start time ts2 when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle) (first increase / decrease start time ts1 < second increase / decrease start time ts2). Thereby, it is possible to more appropriately suppress a specific part of the user from being continuously pressed relatively strongly.

[0081] The control device 16 executes an increasing / decreasing process (ST3) that generates an oscillation Vd in which the seat surface angle θ increases and decreases with a predetermined oscillation period T. As a result, it is possible to continuously suppress the situation where a specific part of the user is continuously pressed relatively strongly.

[0082] The control device 16 sets the oscillation period T according to the seat surface angle θ (ST1). According to the seat surface angle θ, the magnitude of the pressure applied to the part that is continuously pressed relatively strongly by the user changes. Therefore, it is possible to more appropriately suppress the situation where a specific part of the user is continuously pressed relatively strongly.

[0083] The control device 16 makes the first oscillation period T1 when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) shorter than the second oscillation period T2 when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle). In the user's thigh, it can be considered that the pressure applied to the part that is continuously pressed relatively strongly is greater when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) than when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle). And the first oscillation period T1 when the seat surface angle θ is larger than the standard seat surface angle (standard seat surface angle < seat surface angle θ) is shorter than the second oscillation period T2 when the seat surface angle θ is less than or equal to the standard seat surface angle (seat surface angle θ ≤ standard seat surface angle) (first oscillation period T1 < second oscillation period T2). As a result, it is possible to more appropriately suppress the situation where a specific part of the user is continuously pressed relatively strongly.

[0084] When the control device 16 determines that the vehicle (automobile) V is turning, it temporarily stops the execution of the increasing / decreasing start determination process (increasing / decreasing process) and suppresses the change in the seat surface angle θ. As a result, the user can respond to the turning of the vehicle (automobile) V without paying attention to the change in the seat surface angle θ.

[0085] <<Second Embodiment>> In this embodiment, the larger the seat surface angle θ is, the shorter the increase / decrease start time ts is set, and the larger the seat surface angle θ is, the shorter the vibration period T of the vibration Vd generated in the increase / decrease process (ST3) is. The configuration of the vehicle seat 1 of this embodiment is the same as that of the vehicle seat 1 of the first embodiment shown in FIGS. 1-3.

[0086] In the ST1 of the increase / decrease start determination process (see FIG. 4), the control device 16 sets the increase / decrease start time ts to a shorter time as the seat surface angle θ is larger. Further, in the ST3 of the increase / decrease start determination process (see FIG. 4), the control device 16 sets the vibration period T to a shorter value as the seat surface angle θ is larger.

[0087] The control device 16 sets the increase / decrease start time ts to a shorter time as the seat surface angle θ is larger (ST1). As the seat surface angle θ is larger, the front end of the seating surface S rises, and the user's knees are lifted upward. And the larger the seat surface angle θ is, the easier it is for the user's feet to leave the floor 3, and the weight of the user's feet is more likely to be applied to the knees. Therefore, it can be considered that the pressure applied to the portion that is continuously pressed relatively strongly in the user's thigh increases as the seat surface angle θ is larger. By setting the increase / decrease start time ts to a shorter time as the seat surface angle θ is larger, it is possible to more appropriately suppress the fact that a specific portion of the user is continuously pressed relatively strongly.

[0088] In the increase / decrease process, the control device 16 sets the vibration period T to a shorter value as the seat surface angle θ is larger. It can be considered that the pressure applied to the portion that is continuously pressed relatively strongly in the user's thigh tends to increase as the seat surface angle θ is larger. Therefore, by setting the vibration period T to a shorter value as the seat surface angle θ is larger, it is possible to more appropriately suppress the fact that a specific portion of the user is continuously pressed relatively strongly.

[0089] <<Third Embodiment>> In this embodiment, the start time of increase / decrease ts and the vibration period T are set based on the pressure distribution on the seating surface S of the seat cushion 4. The vehicle seat 1 has, as a biological sensor 21, a planar pressure sensor (not shown) under the seating surface S of the seat cushion 4 (between the skin material and the pad). The pressure sensor measures the pressure distribution of the pressure applied to the seating surface S by the user. The configuration of the vehicle seat 1 in this embodiment is the same as that of the vehicle seat 1 in the first embodiment shown in FIGS. 1-3, except for the pressure sensor.

[0090] The control device 16 calculates the start time of increase / decrease ts (ST1) and calculates the vibration period T (ST3) based on the pressure distribution measured by the pressure sensor. The control device 16 may shorten the start time of increase / decrease ts and shorten the vibration period T as the pressure at the portion where the highest pressure is detected in the pressure distribution is higher. Thereby, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0091] The control device 16 may calculate the start time of increase / decrease ts and the vibration period T based on the seat surface angle θ and the pressure distribution measured by the pressure sensor. The control device 16 may shorten the start time of increase / decrease ts and shorten the vibration period T as the pressure at the portion where the highest pressure is detected in the pressure distribution is higher and as the seat surface angle θ is larger. Thereby, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user.

[0092] <<Fourth Embodiment>> In this embodiment, the start time of increase / decrease ts and the vibration period T are set based on the blood flow volume of the user. The vehicle seat 1 has, as a biological sensor 21, an optical blood flow sensor that measures the blood flow volume in the subcutaneous blood vessels of the user. The blood flow sensor is provided on the vehicle seat 1 so as to be able to measure the blood flow volume at a predetermined position (for example, the buttocks or the head) of the user. The configuration of the vehicle seat 1 in this embodiment is the same as that of the vehicle seat 1 in the first embodiment shown in FIGS. 1-3, except for the blood flow sensor.

[0093] The control device 16 calculates the increase / decrease start time ts (ST1) and calculates the vibration cycle T (ST3) based on the blood flow rate measured by the blood flow sensor. The control device 16 may shorten the increase / decrease start time ts and shorten the vibration cycle T as the blood flow rate measured by the blood flow sensor is lower. It can be considered that the higher the probability of poor blood circulation as the blood flow rate is lower. By calculating the increase / decrease start time ts and the vibration cycle T based on the user's blood flow rate, it is possible to more appropriately suppress the continuous relatively strong compression of a specific part of the user. Note that the control device 16 may calculate the increase / decrease start time ts and the vibration cycle T based on the seat surface angle θ and the blood flow rate measured by the blood flow sensor. The control device 16 may shorten the increase / decrease start time ts and shorten the vibration cycle T as the blood flow rate measured by the blood flow sensor is lower and as the seat surface angle θ is larger.

[0094] <<Fifth Embodiment>> As shown in FIGS. 6 and 7, in the present embodiment, the pad and the skin material of the seat cushion 4 are divided into three parts: a left part 111L, a central part 111M, and a right part 111R. The seat surface angle changing device 11 (see FIG. 1) has, as the seat surface angle changing actuator 10, a seat surface angle changing actuator 10L provided in the left part 111L (see FIGS. 6 and 7) of the seat cushion 4 and a seat surface angle changing actuator 10R provided in the right part 111R.

[0095] The control device 16 can change the left seat surface angle θL of the left part 111L of the seat cushion 4 and the right seat surface angle θR of the right part 111R of the seat cushion 4 to different angles. The configuration of the vehicle seat 1 of the present embodiment is the same as that of the vehicle seat 1 of the first embodiment shown in FIGS. 1 to 3 except for the seat cushion 4 and the seat surface angle changing actuators 10L and 10R.

[0096] Unlike the increase / decrease process of the first embodiment, the increase / decrease process of this embodiment changes the left seat surface angle θL and the right seat surface angle θR to different angles based on the seat surface angle θ. When the control device 16 is not executing the increase / decrease process, the control device 16 sets the left seat surface angle θL and the right seat surface angle θR to the same angle (left seat surface angle θL = right seat surface angle θR = seat surface angle θ). The control device 16 of this embodiment executes the cumulative seating time calculation process, the seating determination process, and the increase / decrease start determination process in the same manner as the control device 16 of the first embodiment.

[0097] As shown in FIG. 8, in the increase / decrease process of this embodiment, the control device 16 alternately changes the left seat surface angle θL and the right seat surface angle θR. The control device 16 continuously generates the vibration VdL1 of the left seat surface angle θL and the vibration VdR1 of the right seat surface angle θR alternately until the user leaves the seat (until the seating flag becomes 1). The increase / decrease process of this embodiment includes a process of changing the left seat surface angle θL and the right seat surface angle θR to different angles from each other. Thereby, it is possible to suppress a specific part of the user from being continuously pressed relatively strongly.

[0098] As shown in FIG. 9, the control device 16 may generate the vibration VdL2 of the left seat surface angle θL and the vibration VdR2 of the right seat surface angle θR in the increase / decrease process. In the vibration VdL2 and the vibration VdR2, the phases of the vibrations are opposite to each other. The increase / decrease process of this embodiment includes a process of changing the left seat surface angle θL and the right seat surface angle θR to different angles from each other. Thereby, it is possible to suppress a specific part of the user from being continuously pressed relatively strongly. Note that the control device 16 may generate only one of the vibrations VdL2 and VdR2 in the increase / decrease process.

[0099] The present invention is not limited to the above embodiment. The vehicle seat of the embodiment may be installed in a vehicle other than a car.

Explanation of Signs

[0100] 1: Vehicle seat 3: Floor 4: Seat cushion 5: Seat back 6: Headrest 9: Support member 10: Seat surface angle change actuator 10L: Seat surface angle change actuator 10R: Seat surface angle change actuator 11: Seat surface angle change device 15: Vehicle state monitoring device 16: Control device 20: Occupancy sensor 22: Seat surface angle sensor 31: Steering angle sensor 111L: Left part 111R: Right part R: Reference plane S: Occupancy surface V: Vehicle Y1: Tilting axis θ: Seat surface angle θL: Left seat surface angle θR: Right seat surface angle

Claims

1. A vehicle seat having a seat cushion that supports a user's buttocks from below and is provided on a floor of the vehicle, a seat angle changing actuator for changing a seat angle, which is an angle between the seat cushion and a reference plane set with respect to the floor; A seating sensor provided on the seat cushion; A control device connected to the seating sensor and the seat angle changing actuator and controlling the seat angle changing actuator, The control device includes: Calculating an accumulated sitting time from the time the user sat down to the present based on an output of the seating sensor; The vehicle seat executes an increase / decrease process for increasing / decreasing the seat angle when the calculated accumulated seating time is equal to or longer than a predetermined increase / decrease start time.

2. The vehicle seat according to claim 1 , wherein the control device changes the increase / decrease start time in accordance with the seat angle.

3. The control device includes: The seat angle can be changed within a range from a maximum angle larger than the standard seat angle to a minimum angle smaller than the standard seat angle, When the seat angle is greater than the standard seat angle, the increase / decrease start time is set to a predetermined first increase / decrease start time, When the seat angle is equal to or smaller than the standard seat angle, the increase / decrease start time is set to a predetermined second increase / decrease start time, The vehicle seat according to claim 2 , wherein the first increase / decrease start time is shorter than the second increase / decrease start time.

4. The vehicle seat according to claim 2 , wherein the control device sets the increase / decrease start time to a shorter time as the seat surface angle increases.

5. The vehicle seat according to claim 1 , wherein the increase / decrease process generates vibrations that increase / decrease the seat angle at a predetermined vibration period.

6. The vehicle seat according to claim 5 , wherein the control device changes the vibration period in accordance with the seat surface angle.

7. The control device includes: The seat angle can be changed within a range from a maximum angle larger than the standard seat angle to a minimum angle smaller than the standard seat angle, If the seat angle is greater than the standard seat angle, the vibration period is set to a predetermined first vibration period; When the seat angle is equal to or smaller than the standard seat angle, the vibration period is set to a predetermined second vibration period, 6. The vehicle seat of claim 5, wherein the first vibration period is shorter than the second vibration period.

8. The vehicle seat according to claim 5 , wherein the control device shortens the vibration period as the seat surface angle increases.

9. The control device includes: connected to a vehicle condition monitoring device that monitors turning of the vehicle; When it is determined that the vehicle is turning based on the output of the vehicle state monitoring device, The vehicle seat according to claim 1 , wherein a change in the seating surface angle is suppressed.

10. The seat angle changing actuator is The seat cushion is provided on the left and right sides, The control device includes: A left seating surface angle of the left portion of the seat cushion and a right seating surface angle of the right portion of the seat cushion can be changed to angles different from each other, The vehicle seat according to claim 1 , wherein the increase / decrease process includes a process for changing the left seating surface angle and the right seating surface angle to angles different from each other.

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