Heat shield

Abstract

The present invention relates to a heat shield for shielding of hot areas of a part. Such heat shields are for instance used for shielding hot areas of combustion engines, especially of catalysts, exhaust manifolds, turbo chargers and the like or also in the conditioning of batteries. Conventionally, they comprise at least one metallic sheet layer. In addition to this metal sheet layer, which renders stability to the heat shield, typically an insulating layer made of insulating material, e.g. porous material is provided as a further layer.

1 - 19 . (canceled) 
     
     
         20 . A heat shield for shielding of hot areas of a part with at least one metallic layer and an insulating layer having a porous insulating material arranged at least in sections adjacent to the metallic layer, comprising:
 at least one flow channel formed into the porous insulating material of the insulating layer on its surface pointing away from the metallic layer, the channel extends as a groove on the surface of the insulating layer which points away from the metallic layer.   
     
     
         21 . The heat shield of  claim 20 , wherein the insulating layer extends over at least 90% of the planar extension of the metallic layer. 
     
     
         22 . The heat shield of  claim 20 , wherein the heat shield is comprised of several partial shells, which in the installed state encircle the part in an annularly closed manner. 
     
     
         23 . The heat shield of  claim 20 , wherein the metallic layer is a sheet selected from the group consisting of a stainless-steel sheet, a fire-aluminated steel sheet, and an aluminum-plated steel sheet. 
     
     
         24 . The heat shield of  claim 20 , wherein the insulating material is a fleece that has been reinforced with a ceramic binder or a fleece that is moulded to a shaped part. 
     
     
         25 . The heat shield of  claim 20 , wherein the insulating material is selected from the group consisting of a glass fiber fleece, an expanded mica wool, a basalt rock wool, a ceramic mass, an expanded clay, a high-temperature foam, and combinations of the foregoing in layers of different materials. 
     
     
         26 . The heat shield of  claim 20 , wherein the insulating layer at least in areas is surface-treated to achieve a reinforced surface, the surface treatment selected from a group consisting of a ceramic-based high-temperature adhesive, coating with a ceramic-based high-temperature lacquer, impregnating with a material and treating by compression under elevated temperature. 
     
     
         27 . The heat shield of  claim 20 , wherein one or several flow channels are formed in the surface of the insulating layer in such a way that they extend distanced to each other. 
     
     
         28 . The heat shield of  claim 27 , wherein the distance between individual sections of a flow channel and/or the distance of several flow channels relative to each other in areas with a higher thermal load of the heat shield is smaller than in areas with a smaller thermal load. 
     
     
         29 . The heat shield of  claim 20 , wherein a housing has a laminar self-contained hollow shape to take up the hot areas. 
     
     
         30 . The heat shield of  claim 20 , wherein one or several of the flow channels are distanced to each other and encircle the hollow space at least once in a surrounding manner. 
     
     
         31 . The heat shield of  claim 29 , wherein the housing is closed so that at least a part of the flow channels at an interface, at which the housing is closed, pass over in a flush manner. 
     
     
         32 . The heat shield of  claim 20 , wherein at least two flow channels are formed which surround the part independent of each other. 
     
     
         33 . The heat shield of  claim 20 , wherein at least one flow channel is helically disposed about the part and shows a varying distance between convolutions of the helix with respect to the main direction of the helix. 
     
     
         34 . The heat shield of  claim 20 , wherein the groove forming one flow channel at least on a section of its longitudinal extension shows a cross-section selected from the group consisting of rectangular, quadratic, trapezoidal and semi-circular. 
     
     
         35 . The heat shield of  claim 20 , wherein the groove forming a flow channel at least on a section of its longitudinal extension shows a cross section that tapers in a conical manner and/or that shows a cross section which along the groove in sections tapers and in sections widens. 
     
     
         36 . The heat shield of  claim 20 , wherein the heat shield further comprises at least one device for an active or passive closing and/or ventilation of at least one of the flow channels. 
     
     
         37 . The heat shield of  claim 20 , wherein the heat shield shields parts of an internal combustion engine, selected from the group consisting of an exhaust manifold, a unit for exhaust treatment, a unit for the supercharging of heat exchangers, a unit for the heating of transmission oil, a unit for heating of the passenger room, and a unit for the battery conditioning. 
     
     
         38 . The heat shield of  claim 20 , wherein the heat shield is arranged at the part so that the insulating layer with its surface pointing away from its metallic layer at least in sections rests on the surface of the part and in these areas the surface of the part together with the grooves of the flow channels at least in sections forms the flow path for a fluid or delimits such. 
     
     
         39 . The heat shield of  claim 20 , wherein the groove extends from one end of the insulating material, across the insulating material to a second end of the insulating material. 
     
     
         40 . The heat shield of  claim 20 , wherein the channel is located on the surface of the insulating material so the channel directly faces the part to be shielded. 
     
     
         41 . The heat shield of  claim 20 , wherein the metallic layer is a sheet selected from the group consisting of a smooth metal sheet and a steel sheet that is dimpled at least in sections.