Abstract: An accelerated weathering apparatus includes a test chamber (30), a specimen supporting means (34), a light source (60) powered by a power source controlled by a ballast, at least one chamber air temperature sensor (26), a black panel temperature sensor (36), and a multiple blower system and control means (52). A first blower (12) draws and circulates outside or fresh air and as second blower (46) optionally draws recirculated air into an air mixing duct. The speeds of the fresh air and recirculated air are independently regulated and controlled by a blower controller based on the chamber air temperature and black panel temperature, respectively. In addition, a humidifier (18) and humidity controller (20) regulates humidity within the system as required.

Abstract: An accelerated weathering apparatus includes a test chamber (30), a specimen supporting means (34), a light source (60) powered by a power source controlled by a ballast, at least one chamber air temperature sensor (26), a black panel temperature sensor (36), and a multiple blower system and control means (52). A first blower (12) draws and circulates outside or fresh air and as second blower (46) optionally draws recirculated air into an air mixing duct. The speeds of the fresh air and recirculated air blowers are independently regulated and controlled by a blower controller based on the chamber air temperature and black panel temperature, respectively. In addition, a humidifier (18) and humidity controller (20) regulates humidity within the system as required.

Abstract: An accelerated weathering apparatus includes a test chamber (30), a specimen supporting means (34), a light source (60) powered by a power source controlled by a ballast, at least one chamber air temperature sensor (26), a black panel temperature sensor (36), and a multiple blower system and control means (52). A first blower (12) draws and circulates outside or fresh air and as second blower (46) optionally draws recirculated air into an air mixing duct. The speeds of the fresh air and recirculated air blowers are independently regulated and controlled by a blower controller based on the chamber air temperature and black panel temperature, respectively. In addition, a humidifier (18) and humidity controller (20) regulates humidity within the system as required.

Abstract: A Weathering apparatus having a light source which irradiates onto specimens located in a specimen supporting wall which is located on a side of a test chamber. The output of the light source is controlled by independently adjustable control channels. Each of the control channels include a light source detector inserted into the test chamber, control circuitry, and ballasts connected to the light sources. The light sources are controlled by the control channels to deliver an output equivalent to a desired set-point. In order to disperse light in an even manner to the specimens, a barrier is provided which interferes in a predetermined pattern with the passage of light produced by the light sources. The apparatus includes a calibrating device which automatically transfers an irradiance signal from a reference detector selectively positioned immediately adjacent the light source detector. The calibration signal is sent to the controller where the re-calibration of a selected control channel is accomplished.

Abstract: A thread cutting diestock assembly is disclosed comprising a ratchet housing having a bore adapted to selectively and detachably receive a large thread cutting die head or an adaptor ring, each of which is provided with ratchet teeth engaged by a pawl on the ratchet housing so as to be rotatably therewith. The adaptor ring has a polygonal bore adapted to detachably receive a small thread cutting die head which interengages with the polygonal bore to preclude relative rotation between the die head and adaptor ring. A circumferentially extending recess in the bore in the ratchet housing carriers a non-circular split retaining spring ring which interengages with the large die head or adaptor ring to detachably secure the latter in the ratchet housing bore, and a circumferentially extending groove in the adaptor ring bore carries a polygonal split retaining spring ring which interengages with the smaller die head to detachably secure the latter in the adaptor ring bore.

Abstract: Compressor inlet control devices control the pressure level at the inlet of a compressor (18) which is operated by an engine (10) equipped with a turbocharger (12) that maintains the intake manifold (16) of the engine (10) at pressure levels greater than atmospheric for most engine operating conditions. A valve (20) limits the pressure level at the inlet of the compressor (18) to a predetermined pressure level to prevent damage to the compressor (18). The valve (20) includes a pressure differential responsive piston (36) which responds to the pressure level at the valve inlet (52) to close a pair of valve members (60,62) to terminate communication between the valve inlet (52) and outlet (54) when the pressure level at the inlet (52) exceeds the predetermined pressure level, and to initiate communication between the inlet (52) and outlet (54) when the pressure level drops below the predetermined pressure level.