A liquid discharge apparatus comprising: a conveyor configured to convey an object in a first direction; a liquid discharger configured to discharge a liquid onto the object at a first position, the liquid discharger including a full-width head extending in a second direction intersecting the first direction; a maintenance device configured to maintain a discharge state of the liquid discharger at a second position away from the first position in the second direction; a position changer configured to move the liquid discharger between the first position and the second position; a position detector configured to detect a position of the object in the second direction; and circuitry configured to cause the position changer to change a head position of the liquid discharger in the second direction in response to the position of the object detected by the position detector; wherein the position changer includes a guide extending in the second direction to guide the liquid discharger in the second direction, characterized in that the position changer further includes: a ball screw extending in the second direction and holding the liquid discharger; and a motor configured to drive the ball screw to move the liquid discharger between the first position and the second position in the second direction; wherein the guide and the ball screw are disposed on opposite sides of the liquid discharger in plan view, and the ball screw and the guide guide the liquid discharger in the second direction between the first position and the second position. a conveyor configured to convey an object in a first direction; a liquid discharger configured to discharge a liquid onto the object at a first position, the liquid discharger including a full-width head extending in a second direction intersecting the first direction; a maintenance device configured to maintain a discharge state of the liquid discharger at a second position away from the first position in the second direction; a position changer configured to move the liquid discharger between the first position and the second position; a position detector configured to detect a position of the object in the second direction; and circuitry configured to cause the position changer to change a head position of the liquid discharger in the second direction in response to the position of the object detected by the position detector; wherein the position changer includes a guide extending in the second direction to guide the liquid discharger in the second direction, characterized in that the position changer further includes: a ball screw extending in the second direction and holding the liquid discharger; and a motor configured to drive the ball screw to move the liquid discharger between the first position and the second position in the second direction; wherein the guide and the ball screw are disposed on opposite sides of the liquid discharger in plan view, and the ball screw and the guide guide the liquid discharger in the second direction between the first position and the second position. a ball screw extending in the second direction and holding the liquid discharger; and a motor configured to drive the ball screw to move the liquid discharger between the first position and the second position in the second direction; wherein the guide and the ball screw are disposed on opposite sides of the liquid discharger in plan view, and the ball screw and the guide guide the liquid discharger in the second direction between the first position and the second position.