摘要:
The invention relates to a metal cylinder head gasket provided with at least one opening corresponding to a combustion chamber of an internal combustion engine, comprising a function layer and an annular support arranged thereon. The functional layer comprises one full bead. The cylinder head gasket is characterised in that the annular support comprises one full bead which is defined on the functional layer, and the annular support comprises one bead which is arranged on the side of the full bead which is oriented away from the combustion chamber The invention also relates to a metal cylinder head gasket provided with at least one opening corresponding to a combustion chamber of an internal combustion engine, comprising an upper functional layer, an annular support and a lower functional layer. The annular support is arranged between the upper functional layer and the lower functional layer and is adjacent to the lower functional layer. The upper functional layer comprises one full bead which is adjacent to the annular support. The cylinder head gasket is characterised in that the lower functional layer comprises one bead which is arranged on the side of the full bead which is oriented away from the combustion chamber.
摘要:
In an inventive stent (10), helical filaments (12, 13) are disposed on a first tubular layer (11). The helical filaments (12, 13) are mutually phase-shifted such that they do not touch and lie in one plane. The helical filaments (12, 13) are completely coated by a second elastic tubular polymer layer (14) which is connected to the first elastic tubular layer (11). Further helical filaments may be disposed on the second elastic tubular layer (14). The inventive stent can be lengthened for introduction into a hollow organ and is self-expanding.
摘要:
A joining method head is proposed for fixation to a movable frame, in particular to a robot, having a holding means for an element to be joined to a part, a joining drive means to move the holding means along a joining direction for joining, and a feeding means for feeding elements to the joining method head. Here a control means to control the joining drive means is arranged at the joining method head spatially distanced from the holding means and the joining drive means, so that the holding means and the joining drive means form a joining tool of small dimensions, and means are provided to pass on the elements fed to a transfer station of the feeding means in each instance to the holding means from in front.
摘要:
A fastening device for fastening a small component, in particular a stud provided with an adhesive flange, to a mounting surface using a heat-activated adhesive that creates an adhesive bond between the component and the mounting surface, has an induction coil to heat the component and/or the adhesive and a holding mechanism which holds the component while the fastening device moves to the bonding position. On the side facing the mounting surface is a bearing surface for the component toward which the component can be brought from outside. The holding device can be advanced to the component by the induction coil and has an electromagnet for generating a holding force that is directed toward the bearing surface.
摘要:
A heating current used to inductively heat a metallic or magnetic work-piece is generated by an inverter supplied by a supply voltage. The inverter includes four switching elements arranged in an H-bridge circuit having two parallel longitudinal branches and a transverse branch. The switches are controlled so the heating current flows through the transverse branch. The diagonally opposed switching elements are switched from a conductive to a non-conductive state in a temporally staggered manner.
摘要:
In an artificial endosphincter (1) for the urethra, comprising a retaining part (2) and a valve (10) which can be manually actuated by pressure from the outside, the retaining part (2) is formed as self-expanding stent. This permits gentle, simple and safe positioning as well as reliable and simple handling of the artificial endosphincter (1).
摘要:
A device and a method are proposed for arc welding of elements, in particular metal studs to coated parts, in particular metal sheets, in which in a first step an element is moved relative to the part to at least partially break up the coating of the part. This produces an electrical contact between part and element, the part and the element being welded to each other in a subsequent step. The element is set in oscillating motion, at least about its lengthwise axis, in order at least partially to break up the coating of the part.
摘要:
Chiral prolinol derivatives of formula (1). The compounds may be used as doping agents for liquid crystals for a wide range of applications, including solid state cholesteric filters for projection displays, circular polarizers and optical filters.
摘要:
The invention relates to a method of welding weld studs to a workpiece, in particular of aluminum in each case, by the stroke ignition method, in which the stroke height(s) of the weld stud (1) is altered as a function of the measured arc voltage and optionally of the arc firing time. In particular, the stroke height(s) of the stud (1) can be increased during the occurrence of short circuits, i.e. during a sudden drop in the arc voltage, preferably in predetermined steps. The weld stud is immersed into a pool of melt after a predetermined period of time of between 5 and 10 ms after the welding current has been switched off. The polarity of the stud or of the workpiece is changed at least once during the welding process. The welding current is interrupted for a predetermined period of time for this purpose. The method leads to an improved, readily reproducible quality of weld.
摘要:
The invention provides a process for making acetic anhydride, wherein methyl acetate and/or dimethylether is (are) reacted with carbon monoxide under substantially anhydrous conditions, at temperatures of 350 to 575 K and under pressures of 1 to 300 bars in the presence of a catalyst system comprised of noble metals belonging to group VIII of the periodic system of the elements, or their compounds and iodine and/or its compounds. More specifically, an aliphatic carboxylic acid with 1 to 8 carbon atoms and at least one heterocyclic aromatic compound, in which at least one hetero atom is a quaternary nitrogen atom are used as promoters.