A sealed linear encoder apparatus provides a measure of relative displacement of two relatively movable members. The sealed linear encoder apparatus includes at least one elongate sealing lip wherein at least a sealing portion of the elongate sealing lip is held in tension along its length.

A sealed linear encoder apparatus provides a measure of relative displacement of two relatively movable members. The sealed linear encoder apparatus includes at least one elongate sealing lip wherein at least a sealing portion of the elongate sealing lip is held in tension along its length.

A length-measuring device includes a hollow section member having a scale disposed therein. The hollow section member has a slot which extends along the scale, wherein, during position measurement, a drive dog of a scanning unit scanning the scale extends through the slot. The slot is sealed by an elastic seal extending along the hollow section member. A sleeve is attached to at least one end of the seal in a pull-off resistant manner. The sleeve has an axial abutment which is effective in a longitudinal direction of the hollow section member and with which the sleeve bears axially against the hollow section member.

A length-measuring device includes a hollow section member having a scale disposed therein. The hollow section member has a slot which extends along the scale, wherein, during position measurement, a drive dog of a scanning unit scanning the scale extends through the slot. The slot is sealed by an elastic seal extending along the hollow section member. A sleeve is attached to at least one end of the seal in a pull-off resistant manner. The sleeve has an axial abutment which is effective in a longitudinal direction of the hollow section member and with which the sleeve bears axially against the hollow section member.