| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable the installation of bearings with the diameter of a shaft part shortly held by forming a thrust bearing and radial bearing structure on the shaft part of a rotor housing. SOLUTION: The shaft part 27 at its lower end of a rotor housing 2 is provided with a bearing part 28 having semi-circular cross section over the entire periphery. The bearing part 28 slidably contacts of the receiving part 123 of the bottom housing 12 to form a thrust bearing. An attachment 3 forms a grooved grease reservoir 33 over the entire periphery of the contact surface against the bottom housing 12. Filling grease in the grease reservoir 33 reduces rotary resistance evolved between the attachment 3 and the bottom housing 12. The attachment 3 slidably contacts the inner circumferential surface 124 of the bottom housing 12 to form a radial bearing. Thus, bearings are provided with the diameter of the shaft part 27 shortly held; the length of a flexible cable wound on the shaft part 27 is shortened as well.</p> |
