Electric resistance heating devices – Heating devices – Radiant heater
Patent
1998-01-19
1999-04-27
Walberg, Teresa
Electric resistance heating devices
Heating devices
Radiant heater
73 86, 73 87, 73150R, F21V 900, G01N 1700
Patent
active
058988165
DESCRIPTION:
BRIEF SUMMARY
The invention relates to methods for regulating the temperature of material samples in a light and weathering test apparatus with a closed-off chamber for samples, in which by means of a radiation arrangement visible light, UV and IR radiation is generated, and to a light and weathering test apparatus.
From German Patent DE 20 14 288, a light and weathering fastness testing apparatus with a sample chamber is known, in which samples located on a cylinder jacket surround a radiation source, and between this source and the samples a cylindrical mirror that selectively reflects the infrared component of the radiation and is permeable to the visible and UV components is provided; the effect of radiation in the short-wave infrared range from 800 to 1000 nm is considered especially problematic. Located in the middle of the cylindrical mirror is a metal tube through which a coolant flows, so that the intensity of the infrared radiation, simultaneously produced and occurring in the form of heat, which intensity grows with the intensity of the UV radiation can be dissipated; in this way, influence on the samples by breakdown reactions resulting from infrared radiation are largely avoided, so that any changes in the sample can be ascribed solely to the effect of UV radiation.
From European Patent Disclosure EP 0 320 209 A1, a weathering test system is also known in which the inside surfaces of samples are located on the inside of an approximately spherically formed mounting stand and exposed to an airstream, passed through it by a blower, and to a light source; with the aid of a regulating device for the blower, a predetermined temperature is maintained in the interior of the sample stand.
Moreover, from German Patent Disclosure DT 24 23 052 A1, a method and an apparatus for testing the weather resistance of samples is known in which for speeding up the testing of the samples, an artificial optical irradiation from one or more radiation sources, which also output ultraviolet or superactinic radiation is provided during twilight, darkness and nighttime; the test stand provided for testing weather resistance of samples in the open air has a sample carrier or a plurality of carriers for the radiation device with a guide and drive device; the radiation sources also output ultraviolet or superactinic radiation, and during the artificial irradiation at night no abnormally elevated temperatures. are attained, since high sample temperatures can cause a different kind of change to the bodies of the samples from that caused in natural weathering in the open air.
It proves to be a problem in the prior art that exact definition of the surface temperature, which should be kept as constant as possible if the samples are to be irradiated in a manner approximating actuality, cannot be performed here. In particular it is not possible for the black standard temperature, measured by a black standard thermometer, to be adjusted independently of other parameters and hence it is not possible to characterize temperature conditions of dark-colored sample bodies with low heat conductivity in the plane of the sample mounts during irradiation in accordance with DIN Standard 53387.
The object of the invention is thus to disclose a method for adjusting or keeping constant the surface temperature of the material samples and an apparatus for testing light and weather fastness having a sample chamber, in which the samples have an adjustable, optionally constant surface temperature which is independent of the intensity of the UV radiation, and in which the sample chamber temperature and atmospheric air circulation or climate control fan speed are kept constant; by means of filters, a radiation is to be output into the sample chamber that approximates global radiation, as disclosed for instance in the publication of the Commission CIE85/1989, First Edition 1989, Table 4.
This object is attained in terms of the method by the characteristics of the body of claim 1.
In an advantageous feature of the method, the intensity of the IR radiation is regulated
REFERENCES:
patent: 3224266 (1965-12-01), Klippert
patent: 4391522 (1983-07-01), Schmid et al.
patent: 4644166 (1987-02-01), Sturm et al.
patent: 5220840 (1993-06-01), Neigoff et al.
patent: 5226318 (1993-07-01), Huber et al.
patent: 5421198 (1995-06-01), More, III et al.
Heeger Roland
March Peter
Rudolph Bernd
Schonlein Arthur
Patel Vinod D
Walberg Teresa
Xenotest Gesellschaft fur die Herstellung von Materialprufgerate
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