Metal working – Method of mechanical manufacture – Heat exchanger or boiler making
Reexamination Certificate
1999-07-27
2001-08-28
Cuda Rosenbaum, Irene (Department: 3726)
Metal working
Method of mechanical manufacture
Heat exchanger or boiler making
C029S428000, C029S890039, C029S017400, C165S135000, C428S068000, C428S075000, C428S076000
Reexamination Certificate
active
06279229
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to a method for manufacturing a heat shield and a heat shield produced with this method.
BACKGROUND OF THE INVENTION
Heat shields of this type are used wherever temperature-sensitive assemblies, components or connection lines have to be protected in such a way that heat radiation cannot impact directly on them. This is especially the case with motor vehicles where hot parts of the drive assembly are arranged in direct spatial proximity to other temperature-sensitive assemblies.
The ever-improving utilisation of the engine compartments of motor vehicles leads to heat-sensitive components having to be arranged very close to very hot components, such as, for example, the exhaust system, the combustion engine or the heat exchangers. There is therefore a great need for heat shields particularly in the automobile industry.
From DE 38 34 054 C2 is known a heat shield, in which, in order to protect from heat radiation, at least two flat materials are used which are connected to one another on at least two edge regions turned away from one another. The flat materials mentioned are connected to one another in such a way that a gap is formed between them. Moreover, with this known heat shield it is important that the flat material facing the source of the heat radiation is so oriented in its expansion characteristic by pre-determined profiling or beading or corresponding choice of material that it expands towards the heat source. Through corresponding configuration, adaptation to the heat load arising should be made possible, since with higher temperatures the spacing of the two flat materials used, which preferably consist of sheet metal, is increased and an enlarged air gap is produced which naturally improves the insulation effect.
This heat shield can be further improved in relation to its insulating effect if a heat insulation layer is applied in addition to the inner surfaces of the flat materials proposed there. Specially suitable for this purpose are particularly organic or inorganic fibre materials, but also metallic woven fabrics, knitted fabrics or expanded metals (grids). These furthermore improve the sound insulation which is also obtained through these heat shields.
This heat shield has, however, the disadvantage that it is not possible for every conceivable contour of the heat shield to be configured, in order to achieve the desired effect for adaptation to the different temperatures. Moreover, the insulating effect is limited if only an air gap is used without additional heat-insulating materials.
However, where heat-insulating materials are used as the heat insulation layer, which are applied to the external plates of the heat shield, increased production and cost outlay must be reckoned with. Alternatively, the heat insulation layer may be inserted between the two external plates of a heat shield. For this purpose, however, the material to be inserted as the heat insulation layer has to be bonded by means of a binding agent. Binding agents of this kind generally have organic components which cause problems at high temperatures. In particular, the organic binding agents used for this purpose are both ecologically and toxicologically unsafe, since at the high temperatures occurring they give off gases or carry out chemical reactions.
From PCT/DE98/00065, therefore, is known a method for manufacturing a heat shield in which an insulating material in powder and/or flake form and free of binding agent is applied to one of the two flat materials formed as plates, and then compacted at least in regions through the effect of pressure. Then the second flat material, also configured as a plate, is laid on the insulating material and brought, for instance by folding, into a positive or non-positive connection with the lower flat material. What is advantageous about this method is that it is possible to do without the use of an ecologically or toxicologically unsafe binding agent. What is disadvantageous, however, is that the loose, pourable insulating material has to be applied exactly to the lower plate in the desired distribution. To this end it is necessary to apply the pourable material exactly to a component of the heat shield to be manufactured. This method of production is therefore expensive and cost-intensive.
Proceeding from the above, it is therefore the object of the present invention to quote a method and a heat shield manufactured with the method, which may be carried out or respectively manufactured simply and with low costs. In particular, the heat shield is intended to be safe from every toxicological and ecological point of view.
SUMMARY OF THE INVENTION
According to the invention, this object is achieved by the method according to the preamble of claim
1
and by the heat shield according to the preamble of claim
27
in conjunction with their respective characteristic features. Advantageous developments of the method according to the invention and of the heat shield according to the invention are given in the dependent claims.
According to the method of the invention, an insulating material in granular, powder and/or flake form, uncompacted or also compacted, is formed in the desired shape corresponding to the heat shield to be manufactured and then applied to one of the two external plates of the heat shield. Then the heat shield is provided with the other external plate and both external plates are connected to one another in a positive or non-positive manner. In this way, the application of suitable insulating material layers to an external plate is simplified and becomes more accurate.
The transfer of the preformed insulating material can be made, for example, through a suction apparatus. If the suction apparatus itself has a contour corresponding to the desired shape, the shape of the insulating material can be created by simple suction of the loose material. If one of the external plates is provided with apertures, it can be fastened to the suction apparatus, for example through suction or magnetically. Then the insulating plate made of loose or compacted material is sucked by the suction apparatus to the surface of the fastened external plate and applied together with the external plate to a second external plate.
If preformed, loose insulating material is applied to the external plate, said material can then be compacted by being pressed with the suction apparatus or another pressing plate, or even with the other external plate of the heat shield, against the first external plate.
Conveying the preformed insulating material to the external plate becomes particularly simple insofar as, before being conveyed, it is compacted into a coherent insulating plate and only then applied to one of the two external plates of a heat shield to be manufactured. This compacted, coherent insulating plate has a certain inherent stability which makes it possible for it to be conveyed. Thereafter the second external plate is laid onto the insulating plate and connected with the other external plate to form the composite according to the invention comprising two external plates with a central insulation layer as a heat shield.
What is advantageous about the method according to the invention is that the insulating material does not have to have any binding agent. Thus no ecological or toxicological reservations arise against a heat shield of this type. Altogether, the low binding forces between the individual grains of the compacted insulating material result furthermore in improved sound insulation and smaller resonance problems in the heat shield according to the invention.
Through compacting the insulating material by a factor of up to 20, preferably by a factor of 5 to 10, to form a coherent insulating plate, sufficient inherent strength of the insulating plate is produced such that it may be conveyed, for example with a flat suction apparatus provided with a perforated plate. In terms of production techniques, this results in the advantage that the insulating material can be brought into the desired shape with the desired th
Bretschneider Bernd
Giacomo Giaimi
Görlich Bruno
Grafl Dieter
Lemke Kai
Cuda Rosenbaum Irene
Dana Corporation
Hong John C.
Rader & Fishman & Grauer, PLLC
LandOfFree
Method for producing a heat shield and heat shield produced... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for producing a heat shield and heat shield produced..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for producing a heat shield and heat shield produced... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2440547