Abstract:
The invention concerns a honeycombed body with a plurality of honeycombs and heat insulation (43) comprising a plurality of stacked and/or wound insulating metal layers (4; 34) which support one another owing to microstructures (5) formed in the insulating metal sheets (34), such that spaces are produced between the latter. The microstructures (5) are between 10 mu m and 250 mu m high. In this way, the heat losses from the honeycombed body to the environment are only low.
Abstract:
An improved honeycomb body having a perimeter which encloses the cross section of the honeycomb body. The honeycomb is formed by folding a strip of metal foil back and forth upon itself to provide folds, the foil having corrugations whereby the corrugations maintain the spacing between the folds. One end and only one end of each fold terminates on the perimeter of the body, the cross section of the body being completely filled with folds. The honeycomb body has increased structural and mechanical integrity and is especially useful as a catalyst support for preparing an automotive catalyst.
Abstract:
The subject invention is a novel catalytic converter (400, 500) having a catalytic core element (202, 302, 402, 502, 602, 702, and 802) which is capable of withstanding the thermal stresses and vibrations encountered in typical catalytic converter applications. The catalytic core element is relatively easy and inexpensive to manufacture, has a relatively long operating life, has a relatively low pressure drop, and can be manufactured having various cross section configurations. The catalytic converter (400, 500) includes a catalytic core element (202, 302, 402, 502, 602, 702, and 802) comprising a rigid, foam-like, metallic material having interconnecting walls (204) defining an open pattern of interconnected pores (206) which join together to form irregular passages extending through the catalytic core element. In order to reduce flow resistance or pressure drop across the catalytic core element (302), the catalytic core element may be formed of at least two individual segments (304) arranged one after the other and contacting one another with their density decreasing sequentially in the direction of the gas flow (F). In order to decrease the activation time of the foam-like metallic material forming the catalytic core element (402), electrical conductors (412) may be connected to the catalytic core element to form an electric circuit whereby a source of electrical potential may be connected across the electrical conductors so that during operation the catalytic core element serves as a resistance between the electrical conductors to rapidly heat the catalytic core element to a selected temperature. The catalytic core element (202, 302, 402, 502, 602, 702, and 802) may be formed into various sizes and configurations and may be placed within the exhaust manifold (700), exhaust pipe (712), or the muffler assembly (804) of an internal combustion engine.
Abstract:
The present invention concerns a catalyser arrangement for motor vehicle exhaust systems, in particular those with spark ignition engines. In the proposed arrangement, exhaust gas is channelled at least in parts of the exhaust system in at least two separate systems (26, 27). Each system has at least one catalytic converter (1) with axial channels. The catalytic converter takes the form of a single honeycomb unit with at least one dividing wall (6, 7, 22, 24) on at least one front face, dividing the housing cross-section (19, 20) and adjacent to the front face of the honeycomb to form an at least nearly tight seal.
Abstract:
The invention concerns an electrically conducting metal honeycomb element for use in particular in electrically heated catalytic converters in vehicle exhaust systems, the honeycomb element including metal constituents made of an iron alloy which is resistant to corrosion at high temperatures, the alloy having an aluminium content greater than 6 % by wt., preferably 6-12 % by wt., in particular 8-10 % by wt., and a chromium content greater than 13 % by wt., preferably 16-22 % by wt., in particular 18-20 % by wt., plus an iron alloy suitable for electrical conductors in electric heaters.
Abstract:
A metallic honeycombed body has an axis (1) and a conical tubular envelope (2) with respect to the axis (2) into which is fitted an arrangement of at least one stack (3) wound around the axis (1) in the manner of an involute. The stack (3) has a plurality of tiered metal sheets (4, 5), including a plurality of corrugated metal sheets (5). Each metal sheet (4, 5) is designed as a ring segment and is delimited by an outer arc (7) approximately circular with respect to a central point (6), as well as by an approximately circular inner arc (8) concentric with respect to the outer arc (7) and located between the outer arc and the central point (6). Each corrugated metal sheet (5) has corrugations that are approximately radially oriented with respect to the central point (6) and have a determined height (h1, h2) in each arc (7, 8). The arcs (7, 8) have lengths (s1, s2) whose ratio is approximately the same as the ratio between the corresponding corrugation heights (h1, h2). This honeycombed body is particularly suitable as a support for a catalyst in the exhaust system of an internal combustion engine that drives a motor vehicle, for example, and is associated as a "pre-catalyst" to an usual, axially straight honeycombed body with a catalyst.
Abstract:
An exhaust and purification device for an internal combustion engine in which an NOx absorbent (19) is disposed in an exhaust passageway of the internal combustion engine, and an NOx oxidizing agent (18) is disposed upstream of the NOx absorbent (19) in the exhaust passageway. The NOx absorbent (19) absorbs NOx when an air-fuel ratio of exhaust gas flowing into the NOx absorbent (19) is lean and emits NOx that it has absorbed when an air-fuel ratio of exhaust gas flowing into the NOx absorbent (19) becomes a theoretical air-fuel ratio or rich. In a case where the temperature of the NOx absorbent (19) is low while a lean mixture is being burnt, NOx oxidized by the NOx oxidizing agent (18) is absorbed by the NOx absorbent (19), while in a case where the temperature of the NOx absorbent (19) is high, NOx is oxidized by the NOx absorbent (19) so as to be absorbed by the NOx absorbent (19).
Abstract:
Described is a device for reducing pollutant levels, in particular in vehicle emissions, the device comprising a housing (1) with a catalyst body (2) disposed inside it to leave a gap between the catalyst body and the wall of the housing and with expanding matting (3) located in the gap between the catalyst and the housing wall. The expanding matting is a heat-resistant non-woven containing, embedded in it, expanding particles whose volume increases when a given temperature, produced by the hot exhaust gases, is reached. An auxiliary heater fitted in the gap between the housing (1) and the catalyst body (2) also enables the expanding matting (3) to be heated to the expansion temperature.
Abstract:
A honeycombed body (1) with an axis (2) is composed of at least one pile (3, 31, 32) of at least one sheet metal (4;5) and contains defined channels (6) through which a fluid can flow through the honeycombed body (1) in a direction essentially parallel to the axis (2). The pile (3, 31, 32) has at least one section (7, 71, 72) wound around the axis (2) upon which rests at least an intermediate layer (8, 81, 82) composed of two sheet metals (9; 10) closely superimposed but not directly secured to each other. These sheet metals (9, 10) have corrugations (11) that extend as an helical line around the axis (2) and that define a sense of helix proper to the honeycombed body (1). This sense of helix allows the honeycombed body (1) to deform under thermal stress by describing a helical movement along the axis (2), without damaging its inner structure. The thermal stability under load of the honeycombed body (1) is essentially only determined by the high temperature resistance of the sheet metal used (4; 5; 9; 10).
Abstract:
Protective material for a catalytic converter block comprises a pad of fibrous material in an envelope (10), wherein the envelope has its depth reduced in at least localised areas or positions by drawing together of opposing faces of the envelope, such as by stitching (16).