Abstract: In order to adjust the fiber orientation of a valve spring retainer made of arbon fiber reinforced synthetic material to the stresses appearing in practical operation, it is suggested that several stacked carbon fiber tissue layers be bedded into the valve spring retainer, that a conical opening run vertical to the tissue layers through these, that the weft and warp threads of the tissue layers are displaced from the cross section of the opening to the outside and each project over a part of the perimeter of the opening and that in the edge area of the opening the displaced weft and warp threads have a greater thickness than in the areas farther away from the opening. Furthermore, a process for the production of such a valve spring retainer is discussed.

Abstract: The rotational vibration drive consists of a first plate attachable to a ed baseplate and a second plate attachable to a clamping plate for the ring laser block. The first and second plates are arranged side by side in the same plane. A torsionally stiff rotational spring linkage joins the first and second plates and has a rotational axis perpendicular to the plane of the beam path of the ring laser. The first and the second plates together with the rotational spring linkage are of unitary construction. Two slots originating from the rotational spring linkage extend between the first and the second plates. A piezoceramic stack drive is arranged in mutually-aligned holes in the first and second plates and acts between the said first and second plates, the axis of the piezoceramic stack drive being positioned centrally in height between surfaces of the first and second plates.

Abstract: A ring laser having at least three corner mirrors, of which one carries a ferromagnetic garnet layer on a substrate and is coated with a plurality of interference layers and magnetized at right angles to the ferromagnetic garnet layer. The ring laser is designed in such a way that the corner mirror which carries the ferromagnetic garnet layer acts in reflection as a Faraday cell and, in particular, in that the ferromagnetic garnet layer is subjected to circularly polarized radiation. The circularly polarized radiation may be produced by arranging in front of the corner mirror which carries the ferromagnetic garnet layer a .lambda./4 retarding plate. Another possibility consists in providing those corner mirrors which in the radiation path are adjacent to the corner mirror which carries the ferromagnetic garnet layer with a plurality of interference layers which are arranged in such a way that circularly polarized radiation is converted into linearly polarized radiation by means of a 90.degree.

Abstract: To prevent friction forces from falsifying output readings obtained upon lication of load between a base plate (1) and a load support plate (2), the base plate and the load support plate are rigidly connected by posts extending from one of the plates to an intermediate coupling element (3) and spokes extending from the coupling element (3) to the other one of the plates, bending deformation strain gauges being applied to the spokes and to the posts, respectively, so that forces applied in any direction will cause bending deformation of the spokes and posts, respectively, which can be evaluated with respect to the applied force.