Patent Application
20070034026
The present disclosure generally relates to a weathering test apparatus, and more particularly, to a portable weathering test apparatus.
Manufacturers of exterior coatings, such as paints and finishes, as well as plastics and other components which tend to degrade under exposure to solar radiation and other weathering effects, often want to know how such products will perform following years of exposure. However, such manufacturers typically require such information in a much shorter time than it would take to expose such materials to weathering effects under normal conditions. Accordingly, accelerated weathering test devices have been developed which accelerate the effects of weathering due to outdoor exposure in a much shorter time so that manufacturers need not actually wait five or ten years in order to determine how their products will hold up after five or ten years of actual outdoor exposure.
Indoor accelerated weathering test apparatus are known to test the accelerated aging characteristics of painted surfaces, fabrics, plastic sheeting and other materials. Such testing is accomplished by exposing the materials to be tested to high intensity radiation from an artificial light source that approximates sunlight, under conditions of controlled and sometimes high temperature and/or humidity inside a test chamber.
The above-described indoor accelerated weathering test apparatus typically include a large cabinet that houses a test chamber and various other components of the apparatus. The test chamber can accommodate a large number of test specimen for weathering tests. However, these indoor weathering test apparatus cannot be easily moved to another location. Portability of the weathering test apparatus can provide testing of specimens at any location. Additionally, because the test chamber of these apparatus can accommodate a large number of test specimens, testing a few specimens may be costly and inefficient.
Therefore, there exists a need in the art for a portable weathering test apparatus.
Certain embodiments are shown in the drawings. However, it is understood that the present disclosure is not limited to the arrangements and instrumentality shown in the attached drawings, wherein:
For the purposes of promoting and understanding the principles disclosed herein, reference will now be made to the preferred embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope is thereby intended. Such alterations and further modifications in the illustrated device and such further applications are the principles disclosed as illustrated therein as being contemplated as would normally occur to one skilled in the art to which this disclosure relates.
In accordance with one principal aspect of the present disclosure, a weathering test apparatus includes a portable housing, a specimen holder disposed in the housing and configured to hold at least one test specimen, a mounting board disposed in the housing at a distance from the specimen holder, an ultraviolet light source disposed on the mounting board and configured to emit ultraviolet radiation toward a testing surface of the specimen, and a power supply circuit operatively coupled to a power supply and the ultraviolet light source.
In accordance with another principal aspect of the present disclosure, a weathering test apparatus includes a portable housing, a specimen holder disposed in the housing and being accessible from outside the housing, the specimen holder configured to hold at least one test specimen, a mounting board disposed in the housing, at least one ultraviolet light source disposed on the mounting board, the ultraviolet light source configured to emit ultraviolet radiation toward the specimen, a power supply circuit disposed in the housing and operatively coupled to a power source, the power supply circuit operatively coupled to the ultraviolet light source to provide power to the ultraviolet light source, and a cooling system operatively coupled to an interior of the housing.
In accordance with another principal aspect of the present disclosure, a method of weathering testing includes placing a test specimen in a specimen holder disposed inside a portable housing, the specimen holder being accessible from outside of the housing, powering an ultraviolet light source mounted to a mounting board disposed in the housing, the ultraviolet light source positioned relative to the specimen holder, emitting ultraviolet radiation toward the test specimen with the ultraviolet light source, diffusing the ultraviolet radiation emitted from the ultraviolet light source toward the test specimen with a diffuser disposed between the ultraviolet light source and the specimen holder, and cooling an interior of the housing.
Referring to
Referring to
The ultraviolet light source 16 is supported by a mounting board 32 that is generally mounted on the support base 30 in parallel with the specimen holders 24. The ultraviolet light source 16 is positioned on the mounting board 32 such that it directs ultraviolet radiation toward the specimen 14. To provide uniform distribution of the ultraviolet radiation on the test specimen 14, a diffuser 34 may be disposed between the ultraviolet light source 16 and the specimen holders 24. The ultraviolet light source 16 may be configured as a single ultraviolet light source 16 or a plurality of ultraviolet light sources 36, which may be configured as light emitting diodes, organic light-emitting diodes or other solid state ultraviolet light source.
The ultraviolet light source 16 generates heat, and therefore can raise the temperature of the mounting board 32 and the interior of the housing 12. Additionally, the temperature of the test specimen 14 may be affected by the heat from the ultraviolet light source 16. To cool the mounting board 32 and the ultraviolet light source 16, the apparatus 10 includes a heat sink 38 that is attached to the back side of the mounting board 32. The heat sink 38 provides conduction cooling for the mounting board and the ultraviolet light source 16. To increase the cooling rate provided by the heat sink 38, the apparatus 10 can also include an inner fan 40 that is positioned in the housing 12, and may be attached to the support base 30, such that it provides air flow towards the heat sink 38. Accordingly, the inner fan 40 provides convection cooling for the heat sink 38, thereby providing additional cooling to the mounting board 32 and the ultraviolet light source 16. The apparatus 10 includes a power supply circuit 42 that provides power to the various components of the apparatus 10 and controls the operation of the apparatus 10. The power supply circuit 42 may include a number of application specific integrated circuits and various electronic components that are generally shown by reference number 44. The electronic components 44 can provide power to the ultraviolet light source 16, the fans 18 and 40, and other components of the apparatus 10 that may need electrical power. The power supply circuit 42 may be mounted on the support base 30.
Although not shown, the power supply circuit 42 may simply be integrated with the support base 30 such that the support base 30 is a circuit substrate on which the various components 44 of the power supply circuit 42 are mounted and connected. In the disclosed examples, however, the power supply circuit 42 is shown to be separate from the support base 30.
Power supply circuit 42 receives power from an external power source through a power plug 46. The power plug 46 is accessible from the outside of the housing 12, and may simply be an electrical plug that is used in typical household appliances and other consumer electronic devices. Accordingly, the power plug 46 can receive power from any power source through an extension cord or the like that can connect the power plug 46 to the power source (not shown, i.e., a wall outlet).
As stated in the foregoing, the power supply circuit 42 also includes components that control the weathering testings of the specimen 14. Accordingly, the power supply circuit 42 may control the output of the ultraviolet light source 16 to control the irradiance on the specimen 14. The power supply circuit 42 may also control the temperature inside the housing 14 to thereby control the temperature of the test specimen 14. Although not shown, the apparatus 10 may include a variety of temperature sensors disposed in the housing 12 so as to determine the temperature of the interior of the housing 12 and the temperature of the specimen 14. Such temperature readings from the sensors can be conveyed to the power supply circuit 42. The power supply circuit 42 can then control the operation of the inner fan 40 and the outer fan 18 to control the temperature of the interior of the housing 12.
Referring to
Furthermore, while the particular preferred embodiments have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teaching of the disclosure. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as limitation. The actual scope of the disclosure is intended to be defined in the following claims when viewed in their proper perspective based on the related art.
