Abstract: A chair (1) includes an installation base (10), a leg column (11) supported by the installation base (10) in a tiltable manner, a seat body (12) supported on an upper part of the leg column (11), an elastic member (19) which urges the leg column (11) to an initial tilted posture, and a coming-off restriction member (22) which restricts coming-off of the leg column (11) from the installation base (10). On a support wall (16) of the installation base (10) having an insertion hole (20) through which part of the coming-off restriction member (22) is inserted, a slide guide (21) coming into slidable contact with a slide guide (21) at a peripheral edge portion of a lower surface side of the insertion hole (20) is provided. The coming-off restriction member (22) has an upwardly protruding spherical guide surface (23) which is slidably brought into contact with the slide guide (21) below the insertion hole (20).

Abstract: A chair (1) includes an installation base (10), a leg column (11) supported by the installation base (10) in a tillable manner, a seat body (12) supported on an upper part of the leg column (11), an elastic member (19) which urges the leg column (11) to an initial tilted posture, and a coming-off restriction member (22) which restricts coming-off of the leg column (11) from the installation base (10). On a support wall (16) of the installation base (10) having an insertion hole (20) through which part of the coming-off restriction member (22) is inserted, a slide guide (21) coming into slidable contact with a slide guide (21) at a peripheral edge portion of a lower surface side of the insertion hole (20) is provided. The coming-off restriction member (22) has an upwardly protruding spherical guide surface (23) which is slidably brought into contact with the slide guide (21) below the insertion hole (20).

Abstract: A communication device includes: a receiving unit that receives image data generated by an imaging process of an imaging device facing a predetermined imaging direction and imaging direction information representing the predetermined imaging direction; an operating unit that generates direction instruction information indicating an imaging direction of the imaging device in response to an operation of the user; an image clipping unit that clips a predetermined region of the image data; a display unit that displays an image based on the image data of the predetermined region; and a region position adjusting unit that adjusts a position of the predetermined region in the image data based on the imaging direction information and the direction instruction information.

Abstract: A communication device includes: a receiving unit that receives image data generated by an imaging process of an imaging device facing a predetermined imaging direction and imaging direction information representing the predetermined imaging direction; an operating unit that generates direction instruction information indicating an imaging direction of the imaging device in response to an operation of the user; an image clipping unit that clips a predetermined region of the image data; a display unit that displays an image based on the image data of the predetermined region; and a region position adjusting unit that adjusts a position of the predetermined region in the image data based on the imaging direction information and the direction instruction information.