Abstract: An ophthalmometric apparatus comprising an eyeball observing device for observing the front part of the eyeball and a measuring unit moving device for moving a measuring unit relative to the eyeball, characterized by: a first optical index forming system that projects a light beam along the optical axis of the eyeball observing device to form a first alignment index in the eyeball; a first optical index detecting system that detects the position of the first alignment index on the basis of the light that travels along the optical axis of the eyeball observing device; a second optical index forming system that projects a light beam on the eyeball along an optical axis inclined at an angle to the optical axis of the eyeball observing device to form a second alignment index in the eyeball; a second optical index detecting system that detects the position of the second alignment index and has an optical axis in a substantially mirror image relation with the optical axis of the second optical index forming system

Abstract: A roll for a mill includes a roll shaft of a circular cross-section having an axis of rotation therethrough and having an outer peripheral surface. A ring of a wear-resistant material having an outer peripheral surface adapted to engage with a metal material to be rolled is disposed around the roll shaft. A tubular sleeve having an inner peripheral surface is disposed between the roll shaft and the ring with the inner peripheral surface mated with the outer peripheral surface of the roll shaft. A layer of adhesive is interposed between the ring and the sleeve for adhesively securing the ring and the sleeve together. The adhesive layer is compressed by the ring and the sleeve so as to be brought into frictional engagement therewith.

Abstract: A roll for a mill includes a roll shaft having a tapered portion disposed intermediate opposite ends thereof. The tapered portion has an outer peripheral surface tapering axially of the roll shaft. A ring of a wear-resistant material is disposed around the tapered portion of the roll shaft. A tubular sleeve having an inner peripheral surface tapering axially thereof is press-fitted between the tapered portion of the roll shaft and the ring to retain the ring in place on the roll shaft for rotation therewith. The sleeve includes an inner groove formed in the inner peripheral surface thereof and a passageway formed therethrough. The passageway is communicated with the inner groove so that pressurized oil is supplied through the passageway into the inner groove.