| 摘要 |
<p>A rolling diaphragm seal is inserted between a pair of telescopic tubes containing a laser beam and a reflective mirror to preclude ambient air or lubricant from impinging on the mirror or for changing the density of the air within the tube to cause a change in intensity of the laser beam. The telescoping tube pairs can be used as part of a control system for the positioning of the beds of an ultra-precise machining apparatus such as found in turning and grinding machines for generating flat, spheric, and aspheric shapes, commonly known as aspheric generators. The rolling diaphragm seal consists of a rubber tube having its ends folded back upon itself and positioned between the inner and outer telescoping tubes of each pair. The ends of the seal tube are held apart in a retaining collar through which air can be inserted to pneumatically pressure the space between the folded back portions of the seal.</p> |
