| 摘要 |
PURPOSE:To provide a rotary valve which is quiet, inexpensive, and large in the number of durable years a service life by a method wherein by rotating a rotor contained in the central part of a case, a valve is moved forward and backward and two delivery ports are alternately opened and closed. CONSTITUTION:When a drive shaft 16 is rotated with the aid of a driven motor, a cam 22 is rotated. First and second delivery ports A and B are alternately opened and closed by means of valves 3 and 4. Air sucked through a suction port 10 is supplied to a rotary air passage 8. In which case, when the valve 3 is opened, the air chamber, communicated with the first delivery port A, of air chambers 31 is expanded. When the valve 4 is opened, the air chamber, communicated with the second delivery port B, of the air chambers 31 is expanded. As noted above, the adjoining air chambers 31 alternately repeat expansion and contraction. In this case, a roller being the drive part of the rotary valve is arranged in a case, an air mat having a fitting surface the area of which is reduced, the rotor and a case between which noise is hardly generated, and being very quiet and producing a massage effect is provided. |
