Abstract: A rare earth oxide superconducting material represented by REBa.sub.2 2Cu.sub.3 O.sub.y (RE is Y, Gd, Dy, Ito, Er or Yb), comprises oxide grains and at least one element selected from Rh and Pt, uniformly dispersed in the grain in a proportion of 0.01-5% by weight (in terms of element) based on the rare earth oxide superconducting material. The rare earth oxide superconducting material can be produced by a melt processing and gives a high critical current density even in a highly magnetic field.

Abstract: An apparatus for providing a sealed trailer wheel assembly is disclosed which includes a waterproof cap sealing the outside of the wheel hub, an air housing providing a substantial enclosure of the space between the inside of the hub and the axle, and an air compressor supplying pressurized air to the enclosure at a rate sufficient to prevent water, sand or other materials from entering into the enclosure and thereby into the location of the wheel bearings. A related method is also disclosed.

Abstract: A disc brake device for use in a vehicle which comprises a disc rotor having annular disc brake surfaces, a wheel hub for supporting the disc rotor and being rotatably supported by a wheel axle via bearings, a stationary dust cover for covering both an outer surface of the disc rotor and an end surface of the wheel hub, and a mud-guard cover which is fixed to the dust cover and which has a peripheral edge portion extending to a position adjacent to the surface of the disc rotor. This disc brake device can prevent muddy water from entering into the inside thereof, thereby preventing the lips of a seal and one of the bearings mounted in the device from being damaged by external muddy water. In addition, the lubricating oil for the bearing can be prevented from degradation by such muddy water.