摘要:
The subject of the invention is a passive indicator of voltage presence used to indicate voltage in electrical conductors, electrically powered devices, power distribution devices and transmission lines of high, medium and low voltage. The indicator according to the invention is characterized in that it has form of a multilayer plate comprising two electrically conductive layers (2, 4) and an intermediate layer (3) of a structure manifesting electrooptical properties, located between them, wherein the intermediate layer is a display element of the indicator, while the conductive layers are electrodes of that display element and they are electrically connected by means of a diode (5), and one of the conductive layers is at least partially transparent. In one of variant embodiments of the indicator according to the invention, at least one of the conductive layers is divided into smaller conductive surfaces, separated from one another and being not in contact with each other, which adhere to the intermediate layer and are electrically connected with the other conductive layer or with its individual surfaces by means of diodes.
摘要:
A description is given of a PTC polymer element (1) as part of an electrical component with a novel structure in which aperture angles (&agr;) on both sides of constrictions (2) in the PTC polymer material are at least 100°. As a result, an improved response behavior can be achieved, and, in connection with further features, the construction of PTC polymer elements which are more rapid, capable of carrying greater currents and have higher dielectric strengths is possible.
摘要:
A protective element for protecting in particular an electric motor against overload currents includes in a polymer matrix, preferably ETFE, for example 40% (by volume) of a first powdered filler of a conductive material, preferably TiB2, so that, as in the case of a PTC element, the resistance increases abruptly at a switching temperature corresponding to the melting temperature of the polymer. Also added are 20% (by volume) of a second powdered filler, a phase transition material which, at a critical temperature below the switching temperature, undergoes a phase transition in which it absorbs heat of transformation. As a result, the response time (T) of the protective element is notably extended in a range of the overload current factor (F) corresponding to higher permissible motor starting currents. Examples of materials which come into consideration for the second filler are those with a solid-solid phase transition such as pentaerythritol, NaNO2, NaNO3 or else with a solid-liquid phase transition such as UHMWPE, quinol or, in particular, microencapsulated metals, alloys and salts.
摘要:
A fuse has a fuse element (6), composed of silver, with constrictions (7) which follow one another at regular intervals, and which fuse element makes contact with a combustible element (8), preferably over its entire length. The combustible element (8) is composed of a combustion compound, which is essentially of a fuel such as guanidine or a guanidine derivative and a metal such as Mg or Al and an oxidant such as KNO3, NaNO3, NH4NO3, KClO4, NaClO4, KMnO4, the proportion of which is overstoichiometric by a factor of at least 1.1, and preferably of at least 10. The combustible compound also preferably contains a binding agent such as paraffin, a thermoplastic or an elastomer, so that it can be extruded. It has an ignition temperature of between 160° C. and 260° C. and emits more than 200 J/g of heat, so that it ignites even in the event of small overcurrents and melts the entire length of the fuse element (6).
摘要:
The invention relates to an electric device with a PTC polymer element having a constriction. The constriction defines a web extending in a main current direction over a length longer than in the prior art, namely longer than 5 mm, preferably longer than 15 mm. Further, the aperture angle of the PTC polymer material at the ends of the web is larger than 100°. A preferred choice of material is given, further. The invention achieves very high voltage-withstand capabilities.
摘要:
A contactor has two contact elements (1, 2) each having a contact member (3, 4) adapted to bear with the contact side (5, 6) thereof against a said contact side of the other contact member for enabling an electric current to flow between said to contact elements. The contact sides of both contact members are provided with serration's (11, 12) extending so that elongated ridge-like peaks (13) of serration's of one said contact side intersect such peaks of the other said contact side while forming a plurality of spots of mutual contact of these contact sides distributed over the area of said contact sides.
摘要:
A compressor comprises a compressor wheel, a diffuser and a device for the wet cleaning of the diffuser of a compressor, the diffuser being arranged downstream of the compressor wheel in the flow direction of the medium to be compressed. The device comprises means for injecting a liquid, which are arranged in such a way that the liquid can be introduced, downstream of the compressor wheel, to the diffuser. The diffuser has at least partially a non-stick coating. A device of this type is suitable for removing deep-seated deposits from the surface of the diffuser.
摘要:
The current-limiting resistor has two connection electrodes (1, 2) which are arranged parallel to one another as well as a resistance body (3) which has PTC behavior and with which large-area contact is made by the connection electrodes (1, 2). A varistor (40) is in electrically conductive contact with the resistance body (3). The resistance body (3) contains two contact areas (50, 51) as well as a response point (60) which is connected in parallel with the varistor (40) via the two contact areas (50, 51) and implements a PTC transition above a threshold value of a current flowing through the resistor.Since the resistance body effects the electrical contact with the varistor (40) in the case of this resistor, no metal connection electrodes are required for the varistor. At the same time, due to the outward displacement of the response point (60) away from the varistor (40), the operational reliability of the resistor is considerably improved.Effective current limiting in load circuits which are operated at high voltage can be achieved by a series circuit formed by a plurality of varistors (40, 41, . . . ) provided in a resistance body (3) which is designed in the form of a meander or is of some other continuous design.
摘要:
A contactor has two contact elements (1, 2) each having a contact member (3, 4) adapted to bear with the contact side (5, 6) thereof against a said contact side of the other contact member for enabling an electric current to flow between said to contact elements. The contact sides of both contact members are provided with serration's (11, 12) extending so that elongated ridge-like peaks (13) of serration's of one said contact side intersect such peaks of the other said contact side while forming a plurality of spots of mutual contact of these contact sides distributed over the area of said contact sides.
摘要:
A compressor includes a compressor wheel, a diffuser and a device for the wet cleaning of the diffuser of a compressor, the diffuser being arranged downstream of the compressor wheel in the flow direction of the medium to be compressed. The device includes an arrangement for injecting a liquid, which is arranged in such a way that the liquid can be introduced, downstream of the compressor wheel, to the diffuser. The diffuser has at least partially a non-stick coating. A device of this type is suitable for removing deep-seated deposits from the surface of the diffuser.