Vehicular seat

Abstract

To provide a vehicular seat that when a seat cushion is tilted, can suppress the seat cushion from biting a foreign matter entering a space below the seat cushion.SOLUTION: A vehicular seat 1, which has a seat cushion 4 that supports the hip of a user from below and is provided on a floor 3 of a vehicle V, comprises: a seating surface angle changing actuator 10 that changes a seating surface angle θ that is an angle formed by a reference surface R set on the floor 3 and the seat cushion 4; an object sensor 103 that detects a foreign matter 102 entering a space 101 below the seat cushion 4; and a control device 16 that is connected to the object sensor 103 and the seating surface angle changing actuator 10 and controls the seating surface angle changing actuator 10. The control device 16 restricts a change of the seating surface angle θ depending on the presence of the foreign matter 102.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] 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 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] Foreign objects may enter the space under the seat cushion. In this case, when changing the inclination of the seating surface of the seat cushion, there is a risk that the seat cushion may bite into the foreign object.

[0005] In view of the above background, an object of the present invention is to provide a vehicle seat capable of suppressing the seat cushion from biting into foreign objects that have entered the space under the seat cushion when the seat cushion tilts.

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 vehicle floor (3) and having a seat cushion (4) that supports a user's buttocks from below, the seat surface angle (θ) being the angle formed between a reference plane (R) set with respect to the floor and the seat cushion, the seat surface angle changing actuator (10) for changing the seat surface angle, an object sensor (18, 103, 106, 107) for detecting foreign matter (102) in a space (101) below the seat cushion, and a control device (16) connected to the object sensor and the seat surface angle changing actuator for controlling the seat surface angle changing actuator, wherein the control device restricts the change of the seat surface angle according to the presence of the foreign matter.

[0007] According to this aspect, when the seat cushion tilts, it is possible to prevent the seat cushion from biting into foreign matter that has entered the space below the seat cushion.

[0008] In the above aspect, when the control device detects the presence of the foreign matter under the seat cushion based on the output of the object sensor, it is preferable to prohibit the change of the seat surface angle.

[0009] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into foreign matter that has entered the space below the seat cushion.

[0010] In the above aspect, when the control device detects the presence of the foreign matter under the seat cushion based on the output of the object sensor, it is preferable to change the boundary value of the changeable range of the seat surface angle to the current seat surface angle.

[0011] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into foreign matter that has entered the space below the seat cushion.

[0012] In the above aspect, when changing the seat surface angle, it is preferable for the control device to detect the foreign matter in the space below the seat cushion based on the output of the object sensor.

[0013] According to this aspect, while the seat surface angle is not changed, the power supply of the object sensor can be turned off. Thereby, power consumption can be suppressed.

[0014] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, the control device calculates the distance between the lower surface (104) of the seat cushion and the foreign object based on the output of the object sensor, and when the distance between the lower surface of the seat cushion and the foreign object is equal to or less than a distance threshold value, it is preferable to prohibit the change of the seat surface angle.

[0015] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0016] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, the control device calculates, as a contact seat surface angle (θfc), the seat surface angle at which it is estimated that the lower surface of the seat cushion contacts the foreign object based on the output of the object sensor, and it is preferable to set the changeable range of the seat surface angle based on the contact seat surface angle.

[0017] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0018] In the above aspect, it is preferable that the control device changes the boundary value of the changeable range of the seat surface angle to the contact seat surface angle.

[0019] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0020] In the above aspect, the object sensor is a pressure sensor (106) provided on the lower surface of the seat cushion, and when the control device detects the foreign object in contact with the pressure sensor based on the output of the pressure sensor, it may prohibit the change of the seat surface angle.

[0021] According to this aspect, it is possible to reliably detect a foreign object that has entered the space under the seat cushion. And it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0022] In the above aspect, the object sensor may be a camera (18).

[0023] According to this aspect, it is possible to reliably detect a foreign object that has entered the space under the seat cushion. And it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0024] In the above aspect, the camera may be provided around the tilting axis related to the seat surface angle.

[0025] According to this aspect, it is possible to reliably detect a foreign object that has entered the space under the seat cushion. And it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0026] In the above aspect, the object sensor may be a proximity sensor.

[0027] According to this aspect, it is possible to reliably detect a foreign object that has entered the space under the seat cushion. And it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

Advantages of the Invention

[0028] In order to solve the above problems, one aspect of the present invention is a vehicle seat (1) provided on a vehicle floor (3) and having a seat cushion (4) that supports a user's buttocks from below, the seat surface angle (θ) being the angle formed between a reference plane (R) set with respect to the floor and the seat cushion, the seat surface angle changing actuator (10) for changing the seat surface angle, an object sensor (18, 103, 106, 107) for detecting a foreign object (102) in a space (101) below the seat cushion, and a control device (16) connected to the object sensor and the seat surface angle changing actuator for controlling the seat surface angle changing actuator, wherein the control device restricts the change of the seat surface angle according to the presence of the foreign object.

[0029] According to this aspect, when the seat cushion tilts, it is possible to prevent the seat cushion from biting into a foreign object that has entered the space below the seat cushion.

[0030] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, it is preferable to prohibit the change of the seat surface angle.

[0031] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space below the seat cushion.

[0032] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, it is preferable to change the boundary value of the changeable range of the seat surface angle to the current seat surface angle.

[0033] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space below the seat cushion.

[0034] In the above aspect, when changing the seat surface angle, it is preferable for the control device to detect the foreign object in the space below the seat cushion based on the output of the object sensor.

[0035] According to this aspect, while the seat surface angle is not changed, the power supply of the object sensor can be turned off. Thereby, power consumption can be suppressed.

[0036] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, the distance between the lower surface (104) of the seat cushion and the foreign object is calculated based on the output of the object sensor, and when the distance between the lower surface of the seat cushion and the foreign object is equal to or less than a distance threshold value, it is preferable to prohibit the change of the seat surface angle.

[0037] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0038] In the above aspect, when the control device detects the presence of the foreign object under the seat cushion based on the output of the object sensor, the seat surface angle at which the lower surface of the seat cushion is estimated to contact the foreign object is calculated as a contact seat surface angle (θfc) based on the output of the object sensor, and the changeable range of the seat surface angle is preferably set based on the contact seat surface angle.

[0039] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0040] In the above aspect, it is preferable that the control device changes the boundary value of the changeable range of the seat surface angle to the contact seat surface angle.

[0041] According to this aspect, it is possible to more reliably prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0042] In the above aspect, the object sensor may be a pressure sensor (106) provided on the lower surface of the seat cushion, and when the control device detects the foreign object in contact with the pressure sensor based on the output of the pressure sensor, it may prohibit the change of the seat surface angle.

[0043] According to this aspect, it is possible to surely detect a foreign object that has entered the space under the seat cushion. And it is possible to more surely prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0044] In the above aspect, the object sensor may be a camera (18).

[0045] According to this aspect, it is possible to surely detect a foreign object that has entered the space under the seat cushion. And it is possible to more surely prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0046] In the above aspect, the camera may be provided around the tilting axis related to the seat surface angle.

[0047] According to this aspect, it is possible to surely detect a foreign object that has entered the space under the seat cushion. And it is possible to more surely prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

[0048] In the above aspect, the object sensor may be a proximity sensor.

[0049] According to this aspect, it is possible to surely detect a foreign object that has entered the space under the seat cushion. And it is possible to more surely prevent the seat cushion from biting into a foreign object that has entered the space under the seat cushion.

Brief Description of the Drawings

[0050]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0051] Hereinafter, with reference to the drawings, the vehicle seat 1 according to the 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 "seat front-rear direction", means the direction as seen from a user seated on the vehicle seat 1.

[0052] <<First Embodiment>> As shown in FIGS. 1 and 2, the vehicle seat 1 is installed on the floor 3 in the vehicle interior 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 seat front-rear direction, and the headrest 6 supports the user's head from the rear in the seat front-rear direction. 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 on the user side of the pad (not shown).

[0053] A rotating device 8 is supported on the floor 3 via a slide device 7. The rotating device 8 rotatably supports a support member 9 with respect to the slide device 7 about a vertical axis Z passing through substantially the center in the seat front-rear direction and the seat width direction. The front end of the seat cushion 4 is tiltably connected to the front end of the support member 9 or in the vicinity thereof about 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, about 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.

[0054] 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 seat surface angle θ (thigh angle). The support member 9 and the seat surface angle changing actuator 10 constitute the main part of a seat surface angle changing device 11 that changes the seat surface angle θ. Since the seating surface S deforms during actual sitting, strictly speaking, it is set with reference to the seat frame. When viewed from the side of the seat, the tilting axis Y1 and the two rotatable connection points to the support member 9 of the seat surface angle changing actuator 10 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 seat surface angle changing actuator 10 expands and contracts, the seat surface angle θ is changed. The seat 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 inclined downward with respect to the reference plane R (the state where the seat surface angle θ is negative, see Fig. 1(A)) and a state where the front end of the seating surface S is inclined upward with respect to the reference plane R (the state where the seat surface angle θ is positive, see Fig. 1(C)).

[0055] 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 seat surface angle changing device 11 may have any configuration as long as the seat cushion 4 can tilt with respect to the reference plane R.

[0056] 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.

[0057] 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.

[0058] The in-vehicle camera 18 is arranged 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 capable of distance imaging based on triangulation such as stereo measurement or light section method.

[0059] The object sensor 19 is a sensor that detects objects inside the vehicle, and may be a proximity sensor, a lidar, an ultrasonic sensor, etc. 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 arranged, for example, along the outer peripheral surface of the seat cushion 4, or may be provided at an appropriate position of the headrest 6. Also, the object sensors 19 may be arranged side by side in the front-rear direction on the door panel or the floor 3.

[0060] 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 receives 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 required.

[0061] The biological sensor 21 may be a heart rate sensor, a respiration sensor, a pressure sensor, or an electroencephalogram sensor. The heart rate 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 heart rate sensor is a sensor that detects the user's heart rate. The heart rate 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 of providing two sheet-like electrodes along the front surface of the seat back 5 and detecting the variation in capacitance between the electrodes due to the movement of the user's chest. 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 thereto, 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 a 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.

[0062] 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.

[0063] 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 (LiDARs).

[0064] The outside vehicle camera 23 images the surroundings of the vehicle V, including objects existing around the vehicle V (e.g., surrounding vehicles and pedestrians), guardrails, curbs, walls, median strips, the shape of the road, road markings drawn on the road, etc. 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 through the front glass, rear glass, or side glass. The outside vehicle camera 23 may be, for example, a stereo camera.

[0065] 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.

[0066] The input / output device 14 receives input operations 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 (e.g., buttons, switches, and / or a microphone 27 that receives the user's voice input) and an output device (e.g., 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 by wire and used as the input / output device 14.

[0067] 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 the position 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.

[0068] 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 configured by a CPU (Central Processing Unit) etc., and 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 control target device 17 so that signals can be transmitted and received by signal lines or wirelessly. The control device 16 and the control target device 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 control target device 17.

[0069] The controlled device 17 controlled by the control device 16 includes, in addition to the above-described slide device 7, rotating 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.

[0070] The control device 16 can calculate the seat surface angle θ from the detected 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 calculate the seat surface angle θ from the control history of the seat surface angle changing actuator 10.

[0071] 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 at 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.

[0072] 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 seat front-rear direction of the seat cushion 4 and the lower end of the seat back 5.

[0073] The vehicle seat 1 of the present embodiment can prevent the seat cushion 4 from biting into a foreign object that has entered under the seat cushion 4.

[0074] As shown in FIG. 4, an in-vehicle camera 18 is provided on the support member 9. The in-vehicle camera 18 is an example of an object sensor 103 that detects a foreign object 102 in the space 101 under the seat cushion 4. The foreign object 102 is a foot, a ball, an umbrella, luggage, or the like. The control device 16 detects the foreign object 102 existing in the space 101 under the seat cushion 4 based on the captured image (output) of the in-vehicle camera 18. Further, the control device 16 calculates the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 based on the captured image (output of the object sensor 103) of the in-vehicle camera 18.

[0075] In order for the user to change the seat surface angle θ, the input / output device 14 includes a change button (not shown) for changing the seat surface angle θ. The change button may be, for example, a button that receives an instruction to change by a predetermined angle (for example, +5 deg or -5 deg). The change button may be a button displayed on the touch panel 26. The change button may be a mechanical switch independent of the touch panel 26. When the change button is pressed, the input / output device 14 outputs an operation signal to the control device 16.

[0076] The control device 16 calculates a target angle θg of the seat surface angle θ according to the operation signal. Then, the control device 16 controls the seat surface angle change actuator 10 to execute a seat surface angle change process of changing the seat surface angle θ from the current seat surface angle θ to the target angle θg. While executing the seat surface angle change process, the control device 16 executes a first seat surface angle limit process at predetermined time intervals (for example, every 50 ms). In the first seat surface angle limit process, the control device 16 may set a change stop flag for stopping the seat surface angle change process to 1. In this case, the control device 16 stops the ongoing seat surface angle change process based on the change stop flag. Thereby, the change of the seat surface angle θ stops. Then, the control device 16 resets the change stop flag to 0. Hereinafter, the details of the first seat surface angle limit process will be described with reference to FIG. 5.

[0077] As shown in FIG. 5, in the first step ST11 of the first seat surface angle limit process, the control device 16 acquires a captured image from the in-vehicle camera 18. When the control device 16 acquires the captured image, it executes step ST12.

[0078] In step ST12, the control device 16 determines whether or not there is a foreign object 102 in the space 101 under the seat cushion 4 based on the captured image. If the control device 16 determines that there is no foreign object 102 in the space 101 under the seat cushion 4, the first seat surface angle limit process ends. If the control device 16 determines that there is a foreign object 102 in the space 101 under the seat cushion 4, it executes ST13.

[0079] In step ST13, the control device 16 calculates the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 based on the captured image of the in-vehicle camera 18. When the control device 16 calculates the distance, it executes step ST14.

[0080] In step ST14, the control device 16 determines whether or not the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 is equal to or less than a predetermined distance threshold. If the control device 16 determines that the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 is equal to or less than the distance threshold (distance ≦ distance threshold), it executes ST15. If the control device 16 determines that the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 is not less than the distance threshold (distance threshold < distance), the first seat surface angle limit process ends.

[0081] In step ST15, the control device 16 sets the change stop flag for stopping the seat surface angle change process to 1. When the control device 16 sets the change stop flag to 1, it ends the first seat surface angle limit process. When the change stop flag becomes 1, the control device 16 stops the ongoing seat surface angle change process. As a result, the change in the seat surface angle θ stops. Therefore, when the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 is equal to or less than the distance threshold (ST14: Yes), the lower surface 104 of the seat cushion 4 is prevented from approaching the foreign object 102. As a result, it is possible to suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 below the seat cushion 4. Note that in step ST15, when the control device 16 sets the change stop flag for stopping the seat surface angle change process to 1 and prohibits the change in the seat surface angle θ, it means that the upper limit angle (boundary value) of the changeable range of the seat surface angle θ is set to the current seat surface angle θ. The changeable range of the seat surface angle θ is the range of the seat surface angle θ that the user can change.

[0082] According to the vehicle seat 1 according to the present embodiment, the control device 16 restricts the change in the seat surface angle θ in response to the presence of the foreign object 102 (ST12 - 15). As a result, it is possible to suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 below the seat cushion 4.

[0083] The timing at which the control device 16 acquires the captured image from the in - vehicle camera 18 in the first seat surface angle limit process (ST11) is when the control device 16 changes the seat surface angle θ. Therefore, while the seat surface angle θ is not changed, the power of the in - vehicle camera 18 can be turned off. Thereby, power consumption can be suppressed.

[0084] When the lower surface 104 of the seat cushion 4 approaches the foreign object 102 to a distance equal to or less than the distance threshold (ST14: Yes), the control device 16 prohibits the change in the seat surface angle θ (ST15). Thereby, it is possible to more reliably suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 below the seat cushion 4.

[0085] As shown in Fig. 4, the vehicle seat 1 has an in-vehicle camera 18 as an object sensor 103. Thereby, it is possible to reliably detect a foreign object 102 that has entered the space 101 under the seat cushion 4. And it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0086] As shown in Fig. 4, the in-vehicle camera 18 is provided around the tilting axis Y1 with respect to the seat surface angle θ. Thereby, the in-vehicle camera 18 can reliably photograph the foreign object 102 existing in the space 101 under the seat cushion 4. And the control device 16 can reliably detect the foreign object 102. As a result, it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 existing in the space 101 under the seat cushion 4.

[0087] While executing the seat surface angle change process for changing the seat surface angle θ to the target angle θg, the control device 16 executes the first seat surface angle limit process at predetermined time intervals (for example, every 50 ms). Thereby, while the control device 16 changes the seat surface angle θ to the target angle θg, it is possible to prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0088] <<Second Embodiment>> The configuration of the vehicle seat 1 according to the second embodiment is the same as that of the vehicle seat 1 according to the first embodiment shown in Figs. 1-4. Immediately before executing the seat surface angle change process for changing the seat surface angle θ to the target angle θg, the control device 16 according to the second embodiment executes the second seat surface angle limit process for setting the changeable range of the seat surface angle θ. When the target angle θg is outside the changeable range, the control device 16 changes the seat surface angle θ to the angle closer to the target angle θg among the upper limit angle or the lower limit angle of the changeable range in the seat surface angle change process. Hereinafter, with reference to Fig. 6, the details of the second seat surface angle limit process will be described.

[0089] As shown in FIG. 6, in the first step ST21 of the second seat surface angle limiting process, the control device 16 acquires a captured image from the in-vehicle camera 18. When the control device 16 acquires the captured image, it executes step ST22.

[0090] In step ST22, the control device 16 determines whether or not there is a foreign object 102 in the space 101 under the seat cushion 4 based on the captured image. If the control device 16 determines that there is no foreign object 102 in the space 101 under the seat cushion 4, it executes ST23. If the control device 16 determines that there is a foreign object 102 in the space 101 under the seat cushion 4, it executes ST24.

[0091] In step ST23, the control device 16 sets the changeable range of the seat surface angle θ to the changeable range of the initial value. The changeable range of the initial value is a range from the maximum angle (see FIG. 1(C)) that is larger than the standard seat surface angle θ, which is the standard seat surface angle (see FIG. 1(B)), to the minimum angle (see FIG. 1(A)) that is smaller than the standard seat surface angle. When the control device 16 sets the changeable range of the seat surface angle θ to the changeable range of the initial value, it ends the second seat surface angle limiting process.

[0092] In step ST24, the control device 16 calculates, as the contact seat surface angle θfc (see FIG. 4), the seat surface angle θ at which the lower surface 104 of the seat cushion 4 is estimated to contact the foreign object 102 based on the captured image. In FIG. 4, the seat cushion 105 at the position estimated to contact the foreign object 102 is shown by a two-dot chain line. The contact seat surface angle θfc is the seat surface angle θ of the seat cushion 105. When the control device 16 calculates the contact seat surface angle θfc, it executes step ST25.

[0093] In step ST25, the control device 16 sets the adjustable range of the seat surface angle θ based on the contact seat surface angle θfc. When the contact seat surface angle θfc is greater than the maximum angle, the control device 16 sets the upper limit angle of the adjustable range to the maximum angle (the adjustable range becomes the initial value). When the contact seat surface angle θfc is smaller than the maximum angle, the control device 16 changes the upper limit angle of the adjustable range to the contact seat surface angle θfc. In this case, the control device 16 may change the upper limit angle of the adjustable range to an angle that is smaller than the contact seat surface angle θfc by a predetermined angle (contact seat surface angle θfc - predetermined angle). After setting the adjustable range, the control device 16 ends the second seat surface angle limit process.

[0094] There may be a case where the target angle θg is greater than the contact seat surface angle θfc. In this case, in the second seat surface angle limit process, since the upper limit angle of the adjustable range of the seat surface angle θ is changed to the contact seat surface angle θfc, it is possible to suppress the seat surface angle θ from becoming greater than the contact seat surface angle θfc. As a result, it is possible to prevent the lower surface 104 of the seat cushion 4 from biting into the foreign object 102 existing in the space 101 under the seat cushion 4. As shown in FIG. 4, when the foreign object 102 exists in the space 101 under the seat cushion 4, the user can operate the input / output device 14 to change the seating surface S within the range from the seating surface Smin with respect to the minimum angle of the seat surface angle θ to the seating surface Sfc with respect to the contact seat surface angle θfc.

[0095] The boundary values of the adjustable range are the lower limit angle and the upper limit angle of the adjustable range. In the present embodiment, when the contact seat surface angle θfc is smaller than the maximum angle, the upper limit angle of the adjustable range is changed to the contact seat surface angle θfc (ST25). Here, it is the upper limit angle that is changed. This is because the tilting axis Y1 (tilting axis Y1 related to the seat surface angle θ) of the seat cushion 4 exists on the front side of the seat cushion 4. When the tilting axis Y1 related to the seat surface angle θ exists on the front side of the seat cushion 4, as the seat surface angle θ increases, the rear part of the lower surface 104 of the seat cushion 4 descends. In this case, when the seat surface angle θ becomes larger than the contact seat surface angle θfc, the lower surface 104 of the seat cushion 4 may bite into the foreign object 102. Therefore, the control device 16 changes the upper limit angle of the adjustable range to the contact seat surface angle θfc so that the seat surface angle θ does not become larger than the contact seat surface angle θfc.

[0096] The tilting axis Y1 (tilting axis Y1 related to the seat surface angle θ) of the seat cushion 4 may be arranged at any position from the front end to the rear end of the seat cushion 4. If the tilting axis Y1 related to the seat surface angle θ exists on the rear side of the seat cushion 4, as the seat surface angle θ decreases, the front part of the lower surface 104 of the seat cushion 4 descends. When the tilting axis Y1 related to the seat surface angle θ exists on the rear side of the seat cushion 4 and the contact seat surface angle θfc is smaller than the minimum angle, the control device 16 changes the lower limit angle (boundary value) of the adjustable range to the contact seat surface angle θfc in ST25.

[0097] According to the vehicle seat 1 according to the present embodiment, the control device 16 sets the adjustable range of the seat surface angle θ based on the contact seat surface angle θfc (ST25). Thereby, it is possible to more reliably suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 below the seat cushion 4.

[0098] The control device 16 changes the upper limit angle (boundary value) of the changeable range of the seat surface angle θ to the contact seat surface angle θfc (ST25). Thereby, it is possible to more reliably suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 below the seat cushion 4.

[0099] <<Third Embodiment>> As shown in FIG. 7, in this embodiment, the in-vehicle camera 18 is fixed to the lower surface 104 of the seat cushion 4. The in-vehicle camera 18 is an example of an object sensor 103 that detects a foreign object 102 in the space 101 below the seat cushion 4. 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. 1-4 except for the arrangement of the in-vehicle camera 18.

[0100] The control device 16 in this embodiment, similar to the control device 16 in the first embodiment, executes the first seat surface angle limiting process at predetermined time intervals (for example, every 50 ms) while executing the seat surface angle change process. The control device 16 may execute the second seat surface angle limiting process, similar to the control device 16 in the second embodiment. The control device 16 may execute the first seat surface angle limiting process similar to the control device 16 in the first embodiment and execute the second seat surface angle limiting process similar to the control device 16 in the second embodiment.

[0101] The in-vehicle camera 18 is fixed to the lower surface 104 of the seat cushion 4. When the seat surface angle θ is changed, the orientation of the in-vehicle camera 18 changes according to the orientation of the lower surface 104 of the seat cushion 4. Thereby, it becomes easy to grasp the positional relationship between the lower surface 104 of the seat cushion 4 and the foreign object 102 from the captured image of the in-vehicle camera 18. As a result, it becomes easy to calculate the distance between the lower surface 104 of the seat cushion 4 and the foreign object 102 from the captured image. Also, it becomes easy to calculate the contact seat surface angle θfc from the captured image. As a result, it is possible to more reliably suppress the seat cushion 4 from biting into the foreign object 102 existing in the space 101 below the seat cushion 4.

[0102] The in-vehicle camera 18 is provided around the tilting axis Y1 with respect to the seat surface angle θ. As a result, the in-vehicle camera 18 can surely photograph the foreign object 102 existing in the space 101 under the seat cushion 4. Then, the control device 16 can surely detect the foreign object 102. As a result, it is possible to more surely suppress the seat cushion 4 from biting into the foreign object 102 existing in the space 101 under the seat cushion 4.

[0103] <<Fourth Embodiment>> As shown in FIG. 8, in the present embodiment, a plurality of pressure sensors 106 are fixed to the lower surface 104 of the seat cushion 4. The pressure sensor 106 is connected to the control device 16. When the pressure sensor 106 comes into contact with the foreign object 102, the pressure sensor 106 detects the pressure received from the foreign object 102. The case where the pressure sensor 106 detects a pressure equal to or higher than a predetermined pressure can be regarded as the case where the pressure sensor 106 detects the foreign object 102. The control device 16 can detect the foreign object 102 based on the output of the pressure sensor 106. The pressure sensor 106 is an example of the object sensor 103 that detects the foreign object 102 in the space 101 under the seat cushion 4. The configuration of the vehicle seat 1 in the present embodiment is the same as that of the vehicle seat 1 in the first embodiment shown in FIGS. 1-4 except for the pressure sensor 106.

[0104] While the control device 16 is executing the seat surface angle change process, when the control device 16 detects the foreign object 102 based on the output of the pressure sensor 106, the currently executing seat surface angle change process is stopped and the change of the seat surface angle θ is stopped (the change of the seat surface angle θ is prohibited). As a result, it is possible to suppress the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4. Note that the fact that the control device 16 has stopped changing the seat surface angle θ means that the boundary value (upper limit angle or lower limit angle) of the changeable range of the seat surface angle θ has been set to the current seat surface angle θ.

[0105] Further, when the control device 16 detects the foreign object 102 based on the output of the pressure sensor 106, the control device 16 may return the seat surface angle θ to the angle before executing the seat surface angle changing process. This makes it easier for the user to know that the foreign object 102 exists.

[0106] According to the vehicle seat 1 according to the present embodiment, when the control device 16 detects that a foreign object 102 exists under the seat cushion 4 based on the output of the pressure sensor 106 (object sensor 103), the control device 16 prohibits the change of the seat surface angle θ. Thereby, it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0107] When the control device 16 detects that the foreign object 102 exists under the seat cushion 4 based on the output of the pressure sensor 106 (object sensor 103), the control device 16 changes the boundary value of the changeable range of the seat surface angle θ to the current seat surface angle θ. Thereby, it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0108] The object sensor 103 is a pressure sensor 106 provided on the lower surface 104 of the seat cushion 4. When the control device 16 detects a foreign object 102 in contact with the pressure sensor 106 based on the output of the pressure sensor 106, the control device 16 suppresses (stops) the change of the seat surface angle θ. Thereby, it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0109] <<Fifth Embodiment>> As shown in FIG. 9, in this embodiment, the proximity sensor 107 is fixed to the lower surface 104 of the seat cushion 4. The proximity sensor 107 is connected to the control device 16. The proximity sensor 107 can output information regarding the presence or absence of a foreign object 102 in the space 101 under the seat cushion 4 and information regarding the distance between the foreign object 102 and the proximity sensor 107. The proximity sensor 107 is an example of an object sensor 103 that detects the foreign object 102 in the space 101 under the seat cushion 4. The method of the proximity sensor 107 is not particularly limited. As the proximity sensor 107, an ultrasonic proximity sensor, an optical proximity sensor, or a capacitance proximity sensor may be used.

[0110] Similar to the control device 16 of the first embodiment, the control device 16 of this embodiment executes the first seat surface angle limiting process at predetermined time intervals (for example, every 50 ms) while executing the seat surface angle changing process. Thereby, it is possible to prevent the lower surface 104 of the seat cushion 4 from biting into the foreign object 102 present in the space 101 under the seat cushion 4. The control device 16 may execute the second seat surface angle limiting process, similar to the control device 16 of the second embodiment. Further, the control device 16 may execute the first seat surface angle limiting process similar to the control device 16 of the first embodiment and execute the second seat surface angle limiting process similar to the control device 16 of the second embodiment.

[0111] According to the vehicle seat 1 according to this embodiment, the vehicle seat 1 has a proximity sensor 107 as the object sensor 103. Thereby, the foreign object 102 that has entered the space 101 under the seat cushion 4 can be reliably detected. And it is possible to more reliably prevent the seat cushion 4 from biting into the foreign object 102 that has entered the space 101 under the seat cushion 4.

[0112] The present invention is not limited to the above embodiments. The vehicle seat of the embodiment may be installed in a vehicle other than a vehicle.

Explanation of reference numerals

[0113] 1: Vehicle seat 3: Floor 10: Seat surface angle change actuator 16: Control device 18: In-vehicle camera 101: Space 102: Foreign object 103: Object sensor 104: Bottom surface 105: Seat cushion 106: Pressure sensor 107: Proximity sensor R: Reference plane S: Sitting surface V: Vehicle Y1: Tilting axis θ: Seat surface angle θfc: Contact 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; an object sensor for detecting a foreign object in a space under the seat cushion; a control device connected to the object sensor and the seat angle change actuator and controlling the seat angle change actuator; The control device limits changes to the seat angle depending on the presence of the foreign object.

2. The control device includes: When the presence of the foreign object under the seat cushion is detected based on the output of the object sensor, 2. The vehicle seat according to claim 1, wherein the seat angle is prohibited from being changed.

3. The control device includes: When the presence of the foreign object under the seat cushion is detected based on the output of the object sensor, The vehicle seat according to claim 1 , wherein a boundary value of the changeable range of the seating angle is changed to the current seating angle.

4. The control device includes:

2. The vehicle seat according to claim 1, wherein the foreign object is detected in the space below the seat cushion based on an output of the object sensor when the seat angle is changed.

5. The control device includes: When the presence of the foreign object under the seat cushion is detected based on the output of the object sensor, calculating a distance between a lower surface of the seat cushion and the foreign object based on the output of the object sensor; The vehicle seat according to claim 1 , wherein a change in the seating surface angle is prohibited when the distance between the lower surface of the seat cushion and the foreign object is equal to or less than a distance threshold value.

6. The control device includes: When the presence of the foreign object under the seat cushion is detected based on the output of the object sensor, calculating, based on the output of the object sensor, the seating angle at which the lower surface of the seat cushion is estimated to come into contact with the foreign object as a contact seating angle; 2. The vehicle seat according to claim 1, wherein the changeable range of the seating surface angle is set based on the contact seating surface angle.

7. The vehicle seat according to claim 6 , wherein the control device changes a boundary value of the changeable range of the seating surface angle to the contact seating surface angle.

8. the object sensor is a pressure sensor provided on a lower surface of the seat cushion, The control device includes: When the foreign object in contact with the pressure sensor is detected based on the output of the pressure sensor, The vehicle seat according to claim 2 , wherein the seat angle is prohibited from being changed.

9. The vehicle seat of claim 1 , wherein the object sensor is a camera.

10. The vehicle seat according to claim 9 , wherein the cameras are provided around a tilt axis related to the seating surface angle.

11. The vehicle seat according to claim 1 , wherein the object sensor is a proximity sensor.

Images