Abstract: Material samples may be tested for weathering by a method which comprises securing the samples to a rack which rotates about a central radiation source, and exposing the samples to irradiation from the source at a first intensity of at least about 1.5 SUNS, while rotating the rack at a rate of at least about 6 rpm. Alternatively, a lower radiation intensity may be provided from the same apparatus, using a lower rotation rate. The method may also comprise a step of varying the inductance of a circuit supplying power to the central radiation source as one changes the intensity of the irradiation, to enhance the constancy of spectral distribution of the irradiation at the different intensities.

Abstract: A two-mode surface defect testing device comprises a first source of substantially collimated light which passes along a first light path system to direct the collimated light to a holder for a surface for testing. The surface reflects the light, which is received and directed from the surface typically through at least some of the first light path system to an image processing apparatus. A second source of light is also provided, for providing substantially non-collimated light from the second source to a surface for testing in the holder, which may be the same surface for testing as above. This non-collimated light is reflected from the surface to image processing apparatus. The light may be non-polarized. By use of the two modes of testing, defects may be respectively detected at the outer surface of a transparent coating over an opaque surface, and defects in the opaque surface itself may also be detected.

Abstract: An apparatus and method for the testing of materials by thermal oxidation is provided. The apparatus comprises a housing having at least one optic-isolated chamber. A photon counting photomultiplier and a heat source, for each optic-isolated chamber, are also provided within the housing. A cell, having a plurality of gas inputs and gas outlets, for holding a sample to be tested, is provided within the housing for each chamber. The gas inputs and outputs are distributed about the cell so as to disperse gas evenly about the material to be tested. The apparatus is used to count the number of photons which escape from a test sample as various oxidation conditions are employed.

Abstract: A weathering testing machine or the like is provided with improved stabilization of conditions such as temperature and humidity, coupled with more accurate readout from sensors on a moving member in the machine, and other sensors and microprocessors.

Abstract: A weathering testing machine or the like is provided with improved stabilization of conditions such as temperature and humidity, coupled with more accurate readout from sensors on a moving member in the machine, and other sensors and microprocessors.

Abstract: A weathering testing system comprises a rack for carrying samples to be tested with the samples having inner-facing surfaces, and a lamp centrally positioned of the samples. Blower means are provided for directing a stream of air through the rack. By this invention, the rack may be relatively rotated with respect to the stream of air to provide added uniformity of blowing conditions to the samples. Also, the lamp may be positioned in an adjustable manner so that it can be placed parallel to the rack for optimum radiation. Also the fitting which holds the lamp may be modified so that the lamp may be installed in only a single rotational position, for increased consistency of light irradiation, which gives more uniform calibration. Likewise, an automatic technique for determining ignition and operating of the lamp is disclosed, where a current sensing system found in prior art units can be dispensed with.

Abstract: The light output of a multi-lamp lightfastness testing chamber defining a sample testing area in the chamber may be performed by sequentially turning on and off each lamp by itself, while measuring from the sample testing area the irradiation provided by each lamp, while adjusting the intensity of irradiation for each lamp to a desired level. Thereafter, individual lamp sensors (56) sense the light intensity of each individual lamp. Typically by a feedback circuit, the power to each lamp is adjusted so that the sensed light intensity of each lamp is maintained within predetermined limits corresponding to the irradiation level measured from the sample testing area.

Abstract: A lightfastness testing chamber comprises an enclosure for samples being tested and at least one, and preferably a plurality of, lamps for irradiating samples in the enclosure. A monitor of the light intensity from each lamp present is provided. By this invention the monitor may comprise a light transmission rod, and preferably one such rod for each of the lamps, having one end positioned adjacent the lamp and another end in communication with light intensity measuring apparatus positioned more remotely from the lamp than the one end. The light transmission rod is preferably positioned on a side of the lamp that is substantially opposed to portions of the lamp that directly irradiate samples in the enclosure. Also, the samples may be moved by an elevatable platform or the like toward and away from the irradiating lamp or lamps to vary as desired the intensity of irradiation applied to the samples.

Abstract: A testing system for determining accelerated weathering characteristics of various items such as fabrics and paint samples. Rack means are provided for carrying samples to be tested. A source of irradiation of the inner-facing surfaces of the samples carried on the rack is also provided, along with a blower system for directing a stream of air through the rack. In accordance with this invention, a generally conical member is positioned in the stream of air to redirect the stream outwardly in a generally conical flow path. The generally conical flow path is positioned by the conical member to flow across the inner-facing surfaces of the samples carried on the rack.

Abstract: A testing system for determining accelerated weathering characteristics of various items such as fabrics and paint samples. Rack means are provided for carrying samples to be tested. A source of irradiation of the inner-facing surfaces of the samples carried on the rack is also provided, along with a blower system for directing a stream of air through the rack. In accordance with this invention, a generally conical member is positioned in the stream of air to redirect the stream outwardly in a generally conical flow path. The generally conical flow path is positioned by the conical member to flow across the inner-facing surfaces of the samples carried on the rack.

Abstract: A radiation sensor comprises a housing, a radiation filter, and a photocell positioned to sense radiation passing through the filter. Means are provided for receiving signals from the photocell indicative of radiation sensed by the photocell. In accordance with this invention, means are provided for hermetically sealing the filter and photocell from the exterior, and also for providing cooling (and optionally heating) of the filter and photocell to hold their respective temperatures below predetermined maximum levels, for improvement of sensing accuracy and operating life.