Abstract: A rocking chair includes a seat, a backrest that is tiltable rearward, a locking spring portion that imparts resistance to the rearward tilting of the backrest, and a resilience adjustment member that changes the degree of resistance of the spring portion to the rearward tilting of the backrest. The resilience adjustment member is a cam that is rotationally operable by a person seated on a seat and the position in which rocking load due to the rearward tilting of the backrest is applied to the spring portion is changed by the cam, so that moment applied to the spring portion changes and the degree of resistance of the spring portion is adjusted.

Abstract: A chair includes a seat, a backrest and a back frame having a rigid structure and arranged behind the backrest with an interval in between. The backrest is attached to the back frame by a first support device arranged at a height position close to an upper end of the backrest and by a second support device arranged at a position lower than the first support device and higher than a seat surface. The first support device is attached to a part close to a right-left middle part of the upper end part in the backrest. The second support device is attached to a left end part and a right end part of the backrest.

Abstract: A rocking chair includes a seat, a backrest that is tiltable rearward, a locking spring portion that imparts resistance to the rearward tilting of the backrest, and a resilience adjustment member that changes the degree of resistance of the spring portion to the rearward tilting of the backrest. The resilience adjustment member is a cam that is rotationally operable by a person seated on a seat and the position in which rocking load due to the rearward tilting of the backrest is applied to the spring portion is changed by the cam, so that moment applied to the spring portion changes and the degree of resistance of the spring portion is adjusted.