Abstract: A modular hollow-fiber filter unit (10; 100; 200) for use in a water purifier includes a jacket member (24; 104; 204) surrounding a bundle (20) of hollow fibers (22; 106; 206) within a housing (12; 102; 202). The jacket member has one or more air-vent passages or pockets (30) defined by air-pervious, liquid-impermeable wall members (42; 64) to vent air bubbles accumulated within the housing (12; 102; 202) of the filter unit.

Abstract: A valve timing adjusting system includes mutually parallel axial fluid paths both formed about a fastening bolt which engages with an axial bore formed at the end of a camshaft. One of the axial paths if formed through the fastening bolt and the other axial path is formed between the outer periphery of the fastening bolt and the inner periphery of the axial bore of the camshaft. This avoids necessity of formation of axial fluid path through the camshaft and thus redudes mashing step in production line to lead lower cost.

Abstract: A roller for use in lithography which comprises a surface layer of finely and uniformly mixed ultra-hard material and lipophilic material. The ultra-hard material is preferably tungsten carbide-cobalt and the lipophilic material is preferably aluminum bronze casting, the aluminum bronze casting being mixed with the tungsten carbide-cobalt in the ratio of 25-40% by weight.

Abstract: A wheeled vehicle having a source of driving power and a chassis extending longitudinally of the vehicle, which comprises a rotatable endless track device disposed between front and rear wheels of the vehicle, a system for selectively raising and lowering the endless track device with respect to the chassis whereby when the endless track device is lowered it is brought into contact with the road surface, and a connecting apparatus for drivably connecting the endless track means with the source of driving power when the endless track device is lowered and brought into contact with the road surface.

Abstract: A shield type hydraulic tunnel boring machine having means for detecting an occurrence of excess excavation due to accidental collapse in tunnel face ground apt to occur during tunnel boring through soft and unstable ground and for further determining the location, shape, scale and the like of such excess excavation occurred is provided. The means comprises optimumly a plurality of rod-shaped members capable of being extended out of and retracted into the machine. Amounts by which these members are paid out until they reach ground wall of any cavity due to the occurred excess excavation are measured to determine the actual state of such cavity. The means is provided preferably at a plurality of proper positions on a shield body of the machine and respective values of the measured amounts at these positions are recorded and displayed, whereby the location, shape, scale and the like of the occurred excess excavation can be confirmed.