Abstract: In various embodiments, both very high speed and very high sensitivity hydrogen detection is achieved by controlling water vapor concentration over the catalyst used to convert hydrogen in sample gas (e.g., ambient air) to water vapor, to provide a substantially stable water vapor mixing level at a target mixing ratio. The naturally-occurring water vapor in the sample gas, without further steps, typically would vary over time within a wide range (e.g., due to changing atmospheric conditions). By controlling a level of water vapor over the catalyst to be substantially equal to a target mixing ratio that is not too low as to impair response time, and not too high as to impair sensitivity, both very high speed and very high sensitivity can be provided.

Abstract: A solar tracking mechanism is used to orient a solar collector to directly face the rays of the sun using a hydraulic actuator and gear motor to both adjust the orientation of the collector and to stabilize it against spurious movement. One or more hydraulic cylinders are connected to act through at least one crank pin to rotate the collector about an axis. Hydraulic fluid is transfered between chambers in the cylinders by means of a low power gear motor. The collector itself is constructed without perforations through an insulating shell, but instead mounting brackets are molded into the shell and are configured to faciliate mounting of the collector.

Abstract: An improved solar tracking arrangement is provided for directing a solar energy collector to face the sun. An electrical control mechanism is provided to detect misalignment of the collector as the sun traverses in relative movement across the sky. When the misalignment exceeds an adjustable limit of tolerance, the tracking system moves the collector to an orientation slightly in advance of the current position of the sun by an amount equal to the limit of tolerance. A threshold light level is required to activate the tracking system, and differential photosensors are employed, the composite signals of which compensate for variations in ambient light level so that the amount of surrounding illumination of the environment does not effect the preset limit of tolerance. The tracking system includes east and west limit switches, which reorient the collector to an eastward facing direction at the end of each day.

Abstract: A solar energy collector is provided with a conduit in which tubing carries a heat collecting fluid within an evacuated jacket that encompasses the tubing and within which the tubing is located in an insulation space. The jacket is transparent to solar radiation within a solar radiation collection portion of the device, and may be armored externally thereof about the tubing as it transports the heat collection fluid to a heat exchanger or a thermal sink.

Abstract: A tracking system is provided for positioning solar energy collection units to face the sun during daylight hours. The collectors are mounted generally in north-south alignment with rotatable connections to a supporting base. The connections are laterally offset from the center of gravity of the collector. Thus, the weight of the collector ends to rotate the collector about the connection points to bring the center of gravity to the lowest possible point, thereby orienting the collector generally to face the western horizon. A rotation restraint mechanism is provided to prevent the uncontrolled rotation of the collector to a degree coordinated with rotation of the earth relative to the sun, thereby positioning the collector to directly face the sun during daylight hours. A rank of collectors in parallel alignment can be connected for tandem rotation under the control of a single rotation restraining mechanism.

Abstract: A tool is provided for manufacturing parabolic solar reflectors. The tool employs an improved smooth convex parabolic surface terminating in edges remote from the parabolic vertex which are preferably placed under elastic tension tending to draw the edges toward each other. The improved convex surface is a film of plastic coated with chromium metal on its exterior surface. A multiple layered thermosetting plastic reflector support is molded onto the convex surface of the tool. The reflector support is removed from the tool and a layer of aluminum is vacuum deposited onto the interior concave parabolic reflector surface.

Abstract: A solar energy collection system is provided in which a parabolic trough is oriented by a drive mechanism to reflect the rays of the sun onto an energy collector located at the parabolic focus. The system is constructed to track the sun to maintain focusing of reflected solar radiation during daylight hours. A counterweight is employed in association with the drive mechanism to effectuate tracking and to maintain gravitational equilibrium of the reflector trough despite changes in elevation of the center of the gravity of the trough. Shock absorbers are provided which inhibit disorientation of the trough by gusts of wind, yet which allow the trough to track the sun. Coaxial construction of the solar energy collector with an evacuated sleeve of parabolic configuration positioned thereabout allows a heat collection medium to circulate in the collector, yet minimizes radiant heat loss.