A chemical bottle is inclined by a bottle push-up mechanism, and a chemical solution is gravitationally injected into a chemical tank from a chemical supply tube line. When a chemical tray is drawn out after completion of chemical injection, the bottle push-up mechanism returns to a planar initial state. In connection with this, the chemical bottle returns to an original set position in which the chemical bottle is in a horizontal state or a plug section faces upward with respect to a gravity direction. This prevents the chemical solution remaining in the chemical bottle from flowing to an outside by gravity.