| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an opening and closing device of a door prepared for fire with safety and relief by utilizing water pressure of tap water. <P>SOLUTION: This device for opening and closing the door 8 is composed of a cylinder piston 1 using water pressure of the tap water and a switching valve 2 for switching flow of tap water. The switching valve is provided at any desired operation position irrespective of a position of the cylinder piston. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
