PROBLEM TO BE SOLVED: To provide a chair for an operator in which an elbow rest for holding the forearm part of the operator is provided on both right and left sides of the chair, the interval between the two elbow rests moves closer to the body for a diagnostic position when the operator is seated, and the right and left interval expands when the operator is to leave the seat so that the elbow rests do not hinder the operator from leaving the seat.SOLUTION: A chair 1 for an operator includes a slide part consisting of inner rails 34L and 34R, and outer rails 27L and 27R that cause a pair of elbow rests 31L and 31R to slide in a right-left direction, a seat part 21 that moves downward when the operator is seated, and, as a gear part that converts the displacement by the downward movement of the seat part 21 to the displacement in a right-left direction of the elbow rests, a gear box 12, a first rack gear 35L, a second rack gear 35R, a third rack gear 26, a first pinion gear 17A, and a second pinion gear.SELECTED DRAWING: Figure 1【課題】椅子の左右両側に術者の前腕部を保持できる肘受を設置し、術者が着座すると両肘受の間隔が、診療ポジション用に身体に近づき、退座しようとすると左右の間隔が広がり退座の邪魔にならない様にした椅子を提供する。【解決手段】術者用椅子１は、一対の肘受３１Ｌ、３１Ｒを左右方向にスライドさせるインナーレール３４Ｌ、３４Ｒとアウターレール２７Ｌ、２７Ｒからなるスライド部と、着座によって下方に移動する座部２１と、座部２１の下方への移動による変位を肘受の左右方向の変位に変換するギヤ部として、ギヤボックス１２、第１ラックギヤ３５Ｌ、第２ラックギヤ３５Ｒ、第３ラックギヤ２６、第１ピニオンギヤ１７Ａ、および、第２ピニオンギヤを備えている。【選択図】図１
