Length-measuring or angle-measuring instrument

摘要

The plastic sealing lips (10, 11), customary in encapsulated length-measuring instruments, for sealing the housing slot (7) tend to swell up when they come into contact for a lengthy time with aggressive coolants in machine tools. The swelling up causes them to adopt a wavy shape, which leads to leaks. It is therefore proposed to extend the lips (10, 11) and mount them in the housing (1) with a prestress of approx. 5% of the overall length. In the event of unavoidable swelling up, the sealing lips (10, 11) are then not thrown open in a wavy shape, but the prestress is merely reduced (Fig. 2). <IMAGE>