Vehicle seat

Abstract

A vehicle seat is provided with a side support device configured to assist vehicle exit behavior of an occupant while stably securing a holding property for the sitting occupant. The vehicle seat includes a side support device configured to support a cushion side portion of a seat cushion to be switchable between a seating available position and a vehicle exit assist position, a lock device configured to lock the cushion side portion in the seating available position, and a lock release device configured to release a lock state of the lock device. The lock release device includes a first lever configured to detect sitting of the occupant on a cushion center portion and a second lever configured to detect sitting of the occupant on the cushion side portion. The lock state is released when the detection by the second lever occurs while the detection by the first lever continues.

What is claimed is: 
     
         1 . A vehicle seat, comprising:
 a seat main body on which an occupant can be seated; and   a side support device configured to support a cushion side portion of the seat main body in a seat widthwise direction to be switchable between a seating available state where the occupant can be seated and a vehicle exit assist state where a vehicle exit behavior of the occupant is assisted, wherein the vehicle seat comprises:   a first detector comprising a first sensor that outputs a detection signal when the occupant sitting on the seat main body is detected;   a second detector configured to detect a state change in a detection subject that changes state in accordance with the vehicle exit behavior of the occupant, the second detector comprises a second sensor that outputs a detection signal when the state change in the detection subject is detected; and   an operation device configured to operate the side support device so that the cushion side portion is supported in the seating available state when the first detector detects the sitting of the occupant after the second detector detects the state change in the detection subject, and so that the cushion side portion is switched from the seating available state to the vehicle exit assist state when the second detector detects the state change in the detection subject after the first detector starts detecting the sitting of the occupant; wherein:   the side support device comprises a lock device configured to lock the cushion side portion in the seating available state;   the operation device comprises an operation control device that operates the side support device to release a lock state of the lock device, and the operation control device operates the side support device to maintain the lock state of the lock device when the operation control device receives the detection signal from the first detector after receiving the detection signal from the second detector, and to release the lock state of the lock device when the operation control device receives the detection signal from the second detector after starting receiving the detection signal from the first detector.   
     
     
         2 . The vehicle seat according to  claim 1 , wherein:
 the operation device is configured to release the lock state of the lock device when the detection by the second detector occurs while the first detector continues to detect the sitting of the occupant.   
     
     
         3 . The vehicle seat according to  claim 1 , wherein:
 the first detector is arranged in a center portion in the seat widthwise direction in the seat main body; and   the second detector is arranged in the cushion side portion in the seat main body.   
     
     
         4 . The vehicle seat according to  claim 3 , wherein:
 the second detector detects sitting of the occupant on the cushion side portion as the vehicle exit behavior of the occupant.   
     
     
         5 . The vehicle seat according to  claim 1 , wherein:
 the seat main body comprises a seat cushion that serves as a sitting portion;   the side support device is configured to support the cushion side portion of the seat cushion to be switchable; and   the first detector and the second detector are respectively arranged in a center portion in a seat front to back direction in the seat cushion.   
     
     
         6 . The vehicle seat according to  claim 1 , further comprising a child seat detector configured to detect an attachment of a child seat to the seat main body, wherein the operation device is configured to operate the side support device so that the cushion side portion cannot be switched when the detection by the child seat detector occurs. 
     
     
         7 . The vehicle seat according to  claim 1 , wherein:
 an anchor member that attaches an attached portion provided for the child seat is provided in the seat main body; and   the first detector and the second detector are respectively arranged outside the anchor member in the seat widthwise direction in the seat main body.   
     
     
         8 . A vehicle seat, comprising:
 a seat main body on which an occupant can be seated; and   a side support device configured to support a cushion side portion of the seat main body in a seat widthwise direction to be switchable between a seating available state where the occupant can be seated and a vehicle exit assist state where a vehicle exit behavior of the occupant is assisted, wherein the vehicle seat comprises:   a first detector configured to detect the occupant sitting on the seat main body;   a second detector configured to detect a state change in a detection subject that changes state in accordance with the vehicle exit behavior of the occupant; and   an operation device configured to operate the side support device so that the cushion side portion is supported in the seating available state when the first detector detects the sitting of the occupant after the second detector detects the state change in the detection subject, and so that the cushion side portion is switched from the seating available state to the vehicle exit assist state when the second detector detects the state change in the detection subject after the first detector starts detecting the sitting of the occupant; wherein:   the side support device comprises a lock device configured to lock the cushion side portion in the seating available state;   the operation device comprises a lock release device configured to release a lock state of the lock device;   the lock release device comprises a first lock release lever that is the first detector and a second lock release lever that is the second detector; and   the lock release device is configured to maintain the lock state of the lock device when an operation by the first lock release lever occurs after the second lock release lever operates, and to release the lock state of the lock device when the operation by the second lock release lever occurs after the first lock release lever starts the operation.   
     
     
         9 . The vehicle seat according to  claim 8 , wherein:
 the operation device is configured to release the lock state of the lock device when the detection by the second detector occurs while the first detector continues to detect the sitting of the occupant.   
     
     
         10 . The vehicle seat according to  claim 8 , wherein:
 the first detector is arranged in a center portion in the seat widthwise direction in the seat main body; and   the second detector is arranged in the cushion side portion in the seat main body.   
     
     
         11 . The vehicle seat according to  claim 10 , wherein:
 the second detector detects sitting of the occupant on the cushion side portion as the vehicle exit behavior of the occupant.   
     
     
         12 . The vehicle seat according to  claim 11 , wherein an area of the first detector for receiving a sitting load imposed by the occupant is larger than an area of the second detector for receiving the sitting load imposed by the occupant. 
     
     
         13 . The vehicle seat according to  claim 8 , wherein:
 the seat main body comprises a seat cushion that serves as a sitting portion;   the side support device is configured to support the cushion side portion of the seat cushion to be switchable; and   the first detector and the second detector are respectively arranged in a center portion in a seat front to back direction in the seat cushion.   
     
     
         14 . The vehicle seat according to  claim 8 , further comprising a child seat detector configured to detect an attachment of a child seat to the seat main body, wherein the operation device is configured to operate the side support device so that the cushion side portion cannot be switched when the detection by the child seat detector occurs. 
     
     
         15 . The vehicle seat according to  claim 8 , wherein:
 an anchor member that attaches an attached portion provided for the child seat is provided in the seat main body; and   the first detector and the second detector are respectively arranged outside the anchor member in the seat widthwise direction in the seat main body.