| 摘要 |
PURPOSE:To prevent a bearing from being broken, by using specific bearings as the bearing between a rotary scroll and a crank shaft and a pin crank bearing, and by disposing resilient member between the outer periphery of the crank pin and the rotary scroll and the like. CONSTITUTION:A rotary shaft 3 provided with a crank shaft 3a is journalled to a casing 2 to which a stationary scroll 1 is secured, by means of bearings 4, 5. In the above-mentioned arrangement, a rotary scroll 6 is fitted onto the crank shaft 3a by means of a roller bearing 7 having a radial gap which is as small as possible. Further, a pin crank 12 which is arranged to serve as a rotation preventing mechanism for the rotary scroll 6, has its upper and lower pin sections which are journalled by means of ball bearings 13, 14 respectively having radial gaps which are as large as possible, to the rotary scroll 6 and the casing 2 so that they are fitted to the latter with a gap which is greater than as usual. Further, rubber O-rings 15, 16 are disposed in ring-like grooves which are formed respectively in the rotary scroll 6 and the casing 2. |
