Abstract: An electric machine includes windings for creating electromagnetic fields and at least one fluid-tight internal housing. The group of windings is in an interior space of one of the at least one internal housing. Each of the at least one group of the windings includes at least two electric connecting sections for connecting the respective group of the windings to an external electrical circuit, wherein the at least two electric connecting sections reach from the interior space through a wall of the respective internal housing to outside the respective internal housing, wherein the at least one internal housing includes a coolant inlet and a coolant outlet, and wherein neighboring windings of the at least one group of the windings enclose gaps between each other, the gaps being in fluid communication with the respective coolant inlet and the coolant outlet to be flown through by a coolant.

Abstract: A heat conducting element for transferring heat away from a heat producing device includes a heat pipe or vapor chamber with a hollow structure that has at least one opening that reaches from outside the hollow structure into the interior of the hollow structure. The opening is sealed by a meltable material, so the interior of the hollow structure is fluid-tight, wherein inside the interior a working fluid in form of a saturated liquid and its vapor is provided for receiving, transferring and dissipating heat. The heat conducting has a predetermined operating temperature range with a minimum operating temperature and a maximum operating temperature. The meltable material has a predetermined melting temperature that exceeds the maximum operating temperature by a predetermined temperature difference, such that the meltable material melts if the hollow structure is exposed to a temperature that reaches the melting temperature to unseal the at least one opening.

Abstract: A fuel cell to provide a higher power density. The fuel cell can be produced by 3D printing in ceramic and has an improved power density by virtue of its spiral shape. In order to better extract the energy generated by the fuel cell, an interconnector sheet can be fastened positively to fastening knobs of the fuel cell by holding eyes. In addition, the interconnector sheet can be fixed by glass solder.

Abstract: A fuel cell to provide a higher power density. The fuel cell can be produced by 3D printing in ceramic and has an improved power density by virtue of its spiral shape. In order to better extract the energy generated by the fuel cell, an interconnector sheet can be fastened positively to fastening knobs of the fuel cell by holding eyes. In addition, the interconnector sheet can be fixed by glass solder.

Abstract: A friction-welding device for the integral joining of components, having an oscillator, which generates a periodic movement of a component and a welding surface provided thereon relative to another, static component and a welding surface provided thereon, with directions of movement parallel to the welding surfaces, having a compression device which presses the welding surfaces together, and a cartridge which accommodates the moved component. The oscillator includes two or a greater, even number of piezoactuators, which are arranged in pairs on a line of application and are able to be prestressed with respect to the cartridge from opposite sides under pressure generation and are able to be moved in a synchronous, oscillating manner together therewith and the component.

Abstract: A form-adaptable electrode structure in layer construction includes at least two conductor layers, between which an insulating layer is disposed, the conductor layers having first and second electrode strips arranged in each case in parallel, and the electrode strips of the first conductor layer being arranged at an angle with respect to the electrode strips of the second conductor layer, so that a net-like structure is formed, and the first electrode strips of the first conductor layer being conductively interconnected with the first electrode strips of the second conductor layer, and the second electrode strips of the first conductor layer being conductively interconnected with the second electrode strips of the second conductor layer via the insulating layer at intersections of the net-like structure.

Abstract: A piezoelectric actuating device for controlling a flap on a rotor blade of a helicopter includes a piezo element arrangement including at least one piezoelectric stack actuator. A power transmission frame is coupled to the piezo element arrangement, the power transmission frame including an abutment and a driven element and generating a force therebetween from a change in length of the piezo element arrangement upon an excitation thereof, the force acting transversely to a direction of a centrifugal force of the rotor blade. A first holding device is provided including a pair of first flexible straps configured to fix the power transmission frame relative to the rotor blade in the direction of the centrifugal force and to allow the power transmission frame to move relative to the rotor blade transversely to the direction of the centrifugal force within a limited range.

Abstract: Rotor blade for a helicopter having an aerodynamic control flap, particularly a camber flap, is integrated essentially in the contour of the blade profile. The camber flap is swivellably arranged on an axis of rotation and is linked to a control rod of a control device outside the axis of rotation, for converting a linear movement into a swivelling movement of the control flap. The control device is disposed by way of roller bearings and bolts aligned in the span direction. Devices are provided which absorb by way of the control flap centrifugal forces of the control device resulting from the rotation of the rotor blade.

Abstract: The invention relates to a piezoelectric actuating device for controlling the flaps on the rotor blade of a helicopter. The inventive device comprises a piezo element arrangement (2) and a power transmission frame (10) which is coupled therewith, is fixed to the rotor blade and generates a force between an abutment (14) and a driven element (13) by changing the length of the piezo element arrangement (2). Said force is effective crosswise in relation to the direction of the centrifugal force of the rotor blade. According to the invention, a first holder (11, 12) which fixes the power transmission frame (10) to the rotor blade in the direction of the centrifugal force and is flexible crosswise in relation to the direction of the centrifugal force and a second holder (15, 16) which fixes the abutment (14) that is provided on the power transmission frame (10) crosswise in relation to the direction of the centrifugal force and is flexible in the direction of the centrifugal force are provided.

Abstract: Rotor blade for a helicopter having an aerodynamic control flap, particularly a camber flap, is integrated essentially in the contour of the blade profile. The camber flap is swivellably arranged on an axis of rotation and is linked to a control rod of a control device outside the axis of rotation, for converting a linear movement into a swivelling movement of the control flap. The control device is disposed by way of roller bearings and bolts aligned in the span direction. Devices are provided which absorb by way of the control flap centrifugal forces of the control device resulting from the rotation of the rotor blade.

Abstract: A rotor blade for a helicopter has a blade root for a fastening in the area of the rotor mast and a radially exterior blade tip. An aerodynamic control flap is integrated essentially in the contour of the blade profile is swivellably disposed in the rotor blade between the blade root and the blade tip. The control flap is disposed at its two ends in each case by way of roller bearings on bearing bolts aligned in the span direction of the rotor blade. The bearing of the control flap which is radially on the outside has devices which provide a support with respect to the centrifugal forces of the control flap upon the rotor blade resulting from the rotation of the rotor blade.

Abstract: A form-adaptable electrode structure in layer construction includes at least two conductor layers, between which an insulating layer is disposed, the conductor layers having first and second electrode strips arranged in each case in parallel, and the electrode strips of the first conductor layer being arranged at an angle with respect to the electrode strips of the second conductor layer, so that a net-like structure is formed, and the first electrode strips of the first conductor layer being conductively interconnected with the first electrode strips of the second conductor layer, and the second electrode strips of the first conductor layer being conductively interconnected with the second electrode strips of the second conductor layer via the insulating layer at intersections of the net-like structure.

Abstract: An aerodynamic component such as a helicopter rotor blade has an aerodynamic flow profile, a free end and a mounting end forming a blade root for attachment to a rotor mast. A blade section between the root and the free end has a leading edge and a trailing edge as viewed in the flow or chord direction. The blade is enclosed on its suction side and its pressure side with a respective skin. A nose flap or leading edge flap is secured to the leading edge by a bearing or hinge. The blade tilting angle is adjustable by piezo-drive elements arranged in at least one pair forming an actuator for each nose flap. The piezo-elements of a pair are arranged in the chord direction one behind the other and the pair is secured to the body of the blade by a fixed point positioned between the elements of a pair. The expansion and contraction from the piezo-element closer to the trailing edge is transmitted to the flap by a push rod.

Abstract: A rotor blade for a helicopter has a blade root for a fastening in the area of the rotor mast and a radially exterior blade tip. An aerodynamic control flap is integrated essentially in the contour of the blade profile is swivellably disposed in the rotor blade between the blade root and the blade tip. The control flap is disposed at its two ends in each case by way of roller bearings on bearing bolts aligned in the span direction of the rotor blade. The bearing of the control flap which is radially on the outside has devices which provide a support with respect to the centrifugal forces of the control flap upon the rotor blade resulting from the rotation of the rotor blade.

Abstract: The piezoelectric actuator consists of at least two disk-shaped congruent bending elements which each have a carrier plate made of a hard-elastic material with a layer of a piezoelectric material applied to one or both sides. Two bending elements respectively are connected with one another by way of at least two bending joints arranged on the circumference of the carrier plates.