摘要:
A process and a system are proposed for short-time arc-welding elements, such as for example metal studs, on to components, such as for example metal sheets, wherein an element in the context of a welding operation is initially raised in relation to the component, a welding arc is formed between the element and the component, and the element is lowered again, the lifting height of the element in relation to the component being detected at least within a time segment between raising and lowering of the element. The initiation of the lowering operation and/or the lowering operation itself is controlled as a factor of the detected lifting height such that a previously specified total welding time is achieved.
摘要:
A liquid crystal switchable color filter switches between three color bands and is preferably used for time-sequential devices, such as projection devices, direct view displays and video cameras. The color filter may employ circularly polarizing selective reflection bands of at least four cholesteric filters together with three liquid crystal switches and related retarder layers. In one embodiment, the handedness of the second cholesteric is equal to the handedness of the third cholesteric filter and opposite to the handedness of the first and fourth cholesteric filter and, for the blocking state of a color band, the optic axis of the corresponding liquid crystal switch is parallel or perpendicular to the polarization direction. This concept leads to improved, excellent color saturation and requires less stringent production tolerances than in the prior art. Moreover, it advantageously allows overlapping color transmission bands thus improving the light efficiency.
摘要:
Compounds of formula (I) wherein A, C and D represent (1) or (2), B represents (3) or (4) wherein at least one of the substituents is other than hydrogen and also at least one of the phenylene rings may be replaced by a 1,4-phenylene ring in which one or two non-adjacent CH groups have been replaced by nitrogen; k, l, m are 0 or 1, wherein k+l+m must be equal to 1 or 2; Z1, Z2, Z3 each independently of the others represents a single bond, —CH2CH2—, —CH2O—, —OCH2—, —COO—, —OOC—, —CH═CH—COO—, —OOC—CH═CH—, —(CH2)4—, —O(CH2)3—, —(CH2)3O— or —C≡C—; R1, R2 represent crosslinkable groups, and S1, S2 represent spacer units.
摘要:
A process for producing, on a metallic substrate, a geometric metal structure having a precise contour, including the steps of: solder coating a solder paste onto the substrate by screen printing to create the geometric metal structure, the solder paste comprising an organic binder system, and 80 to 95 weight % of a mixture of a nickel-based solder and a pulverulent alloy of nickel with at least one member selected from the group consisting of chromium, molybdenum, tungsten, manganese and iron, provided as a higher-melting metallic filler, wherein a weight ratio of solder to filler is 2-6:1, an average grain size of the solder is between 10 and 50 &mgr;m, and a grain size ratio of solder to filler, relative to the average grain size is from 0.5-2.5:1; drying the structure; decomposing the organic binder system present in the solder paste, without leaving a reside, by a heat treatment; and raising the temperature until the resulting solder material liquifies.
摘要:
Polymerisable optically active compounds have the general formula: ##STR1## where: W.sup.1 denotes a polymerisable residue,S.sup.1 denotes a spacer unit,Y.sup.1 denotes a single bond, or one of the groups --O--, --COO--, --OOC--, --OCOO--, --S--, --CONH-- or --NHCO--,M denotes a divalent mesogenic group, andR.sup.1 and R.sup.2 denote straight chain, branched or cyclic alkyl groups with up to 8 carbon atom.
摘要:
In liquid crystal display cells comprising a liquid crystal (7) disposed between two substrate plates (1,2) provided with drive electrodes (3,4), the orientation layer (5,6) on the inner sides of the plates where the electrodes are disposed comprises an oriented photopolymer layer. This layer is formed by irradiating photopolymer layer. This layer is formed by irradiating photoreactive material with linear polarized light.
摘要:
The image-producing device comprises a liquid crystal cell with a liquid crystal (10, 21, 44) between two plates provided with drive electrodes (2, 6; 24, 25; 42, 46) and wall orientation layer (3, 7; 26,27; 43, 45) and an optically anisotropic polymeric additional element (9, 31, 52). The additional element, which can be a separate element or in the form of a coating or a foil stuck directly to the cell, comprises an oriented photopolymer.
摘要:
Polymeric coatings having optically non-linear or optically anisotropic properties in selected areas and of any arbitrary shape including a pattern. These zones are sharply defined from surfaces having centro-symmetrical or isotropic configurations or from surfaces with different optically non-linear or anisotropic properties. The polymeric coating has optically non-linear and/or mesogenic side chains, selected surface areas of which are cross-linked by the action of light, the zones which have optically non-linear or anisotropic properties being subjected to the influence or orienting fields or forces during the cross-linking process. The distances between optically different zones are limited to typically about 1 .mu.m.
摘要:
An original holder for a printing plate processing apparatus for rapid exchange of an original in a vacuum frame covered by a glass plate and exposed in the exposure device of a printing plate processing apparatus. The glass plate is held in its open position by a gas pressure element to facilitate insertion of the original. Two U-shaped metal sheets serve as supports for two vacuum frames which are each evacuated following insertion of an original and closing of the glass cover plate. Swivel joints are attached at the sides of the supports which enable the original holder to be pivoted through an angle of 360.degree. and which are additionally horizontally slidable in the guides of supporting and guiding arms. The vacuum frames are individually pivotably mounted in their supports by ball guides in guide tracks. When one of the vacuum frames is in the vertical exposure position in the exposure opening in the wall of the exposure device housing and its support is secured to the housing wall by locking devices, the second vacuum frame is pivoted into the horizontal position by means of a lever so that an original can be inserted therein. The second vacuum frame is thereafter folded back again to the vertical position in its support. After exposure of the original in the first vacuum frame, the entire original holder is drawn into the change position, pivoted through 180.degree., and the original in the second vacuum frame is moved into the exposure opening. In an alternate embodiment, the swivel joints are fixedly mounted adjacent the edges of the exposure opening, and the original holder pivots inside the exposure device.
摘要:
Known chimneys or chimney furnaces use flue gas flow units for heating buildings, said devices having displaceable or fixed obstacles for deflecting flue gas for generating flue gas turbulence. The invention relates to a device and method for transferring heat through a flue gas discharge pipe in which pivotal guide plates are inserted in the longitudinal direction of the pipe run, at which the flue gas flow is more or less deflected in a sinuous line as function of the pivot angle of the guide plates that can be adjusted during furnace operation. A fan can increase the flue gas flow. An optional furnace heat exchanger generates additional hot water as needed. The controller activates the actuators for the fan, guide plate pivot angle setting, and at least one circulating pump as a function of the prescribed controlled variables such as flue gas temperature, reservoir temperature, heat exchanger performance, or flue gas flow.