Abstract: A body of metal (1) provided with a central through passage (2) presenting at least a cylindrical surface (3). A disc (10) is positioned in the cylindrical surface (3). A cylindrical part (12) of synthetic resin is fixed in the body (1), this part (12) presenting an internal cylindrical surface having the shape of a diabolo the medial part of which (13) receives a pivot. The internal frontal face of the part (12) of synthetic resin is in contact with the face of the disc (10).

Abstract: A height adjusting device for machines or machine elements comprises three adjustment members positioned atop one another and together determining two sets of opposing surfaces. These surfaces allow a gyroscopic movement of the uppermost adjustment member, and the height of the height adjusting device can be adjusted stepwise, one of the two opposing surfaces in the first set of surfaces comprising one or more aligned supporting projections. These projections can cooperate selectively and tiltably with one or more recesses in a row of recesses in the second surface of the first set of surfaces. The depth of the recesses in said row of recesses varies stepwise. The surfaces of the second set of surfaces are provided with cooperating secondary projections and secondary recesses. The line on which the secondary projections are positioned forms an angle of substantially 90.degree. with the line on which the supporting projections are positioned.

Abstract: For a bearing bushing of generally cup-like form for universal joints including a universal joint pin, a check plate disposed between the axial end face of the pin and the bottom wall of the bushing, said check plate having on the side thereof confronting the pin concentric or circumferentially distributed projections with check surfaces and in that, proceeding from the end surface facing away from the pin, it has recesses or the like, which are arranged under the projections in the axial direction.

Abstract: A body of brass (1) provided with a central through passage (2) presenting two cylindrical surfaces (3,4) of different diameters. A disc of hard stone (10) is driven in the first cylindrical surface (3). A pierced steel ring (11) is driven in the second cylindrical surface. One of the annular faces (5) of this ring (11) is in contact with one of the faces of the disc of hard stone (10). A cylindrical part (12) of synthetic resin is fixed in the steel ring (11), this part (12) presenting an internal cylindrical surface having the shape of a diabolo the medial part of which (13) receives a pivot. The internal frontal face of the part (12) of synthetic resin is in contact with the face of the disc (10) of hard stone which itself is in contact with the steel ring (11).

Abstract: The front fan of a ducted fan gas turbine engine is connected to the low pressure turbine of the gas generator by a shaft so as to be driven thereby. If the shaft breaks, air loads on the fan tend to pull it from the engine. It is known to provide a fail/safe shaft over and above the normal shaft which is retained at one end by some means and has a flange on its upstream end, to retain the fan via its disc. The invention obviates the heavy and expensive fail/safe shaft and substitutes a first annular shoulder 40 on the inner race of the fan bearing 20 and a further shoulder 42 on fixed structure 38. If the fan attempts to exit the engine, the two shoulders 40, 42 engage and so retain the fan.

Abstract: A highly reliable device for stopping the operation of a flywheel apparatus for storing electrical energy in the event of interruption of power supply includes a thrust plate 11 connected to the rotatory part of the apparatus, and having a lower surface defining a thrust bearing surface. A pressure receiving surface 26 facing the lower surface of the thrust plate, and defining a thrust bearing surface is provided with a plurality of radially extending grooves 27 each having at least one sidewall which defines an upwardly inclined land 28 as viewed in the direction of rotation of the rotatory part. Provided below the pressure receiving surface 26 is a cooling fluid passage 33 connected to an electromagnetic valve 35 adapted to open upon interruption of power supply to allow a cooling fluid to flow into the passage 33. The device further includes means for maintaining a hydraulic fluid between the thrust bearing surfaces during interruption of power supply.