Abstract: A hat includes a shell, and an air filtration system for providing a protective stream of air across the face of the wearer of the hat. The shell defines an exterior of the hat. At the back of the shell is a fan housing which contains a fan and defines an interior through which air is passed through the hat. The filtration system includes a filter cartridge and a retaining basket. The filter cartridge includes a filter medium. The filter system is removeably positioned adjacent to and across the fan housing so as to filter air passing into the interior of the hat. The filter cartridge is removeably engaged to the retaining basket. The retaining basket retains the cartridge to the hat and ensures proper positioning of the filter cartridge.

Abstract: A hard hat with air flow system includes a hard hat with an air flow passage for passing air through the hard hat and out exits ports at the front of the hat to provide a shield of air downward across the face of a user. The system includes an air filtration system, a blower assembly for drawing air through the air filter and pushing the filtered air into the air flow passage of the hard hat, and a power supply for powering the blower. The filtration system, blower assembly and power supply being supported on a harness such as a belt or backpack, external from the hard hat.

Abstract: A central distribution unit (CDU) for circulating coolant is disclosed. The CDU may operate under negative pressure and can have a number of operation modes including: normal operation, pump priming, fill, drain, purge and vacuum test. The CDU includes various valves, pumps and sensors, the placement and actuation of which transitions the CDU into the various modes.

Abstract: A braille cell and associated braille pin support and pin actuation assemblies are disclosed. The braille cell can include a frame, braille pins movable up and down between raised and lowered positions, and a pin actuation assembly to individually move the pins. The braille cell can include support arms, each of which having a base end connected to the frame and a pin end connected to and following a motion of a respective pin between its raised and lowered positions. The pin actuation assembly can include pin actuation units, each having a motor with a rotatable motor shaft and multiple cams mounted on the shaft, each for selectively actuating a respective pin. Each pin actuation unit can also include an angular position sensing system for monitoring, for example magnetically, a passage of the shaft through a reference angular position, and deriving information about a current angular position of the shaft.

Abstract: A hard hat with air flow system includes a hard hat with an air flow passage for passing air through the hard hat and out exits ports at the front of the hat to provide a shield of air downward across the face of a user. The system includes an air filtration system, a blower assembly for drawing air through the air filter and pushing the filtered air into the air flow passage of the hard hat, and a power supply for powering the blower. The filtration system, blower assembly and power supply being supported on a harness such as a belt or backpack, external from the hard hat.

Abstract: A pump with two independent motors is disclosed. The first motor is mechanically connected to a first rotor comprising a first plurality of teeth radiating from the center of the first rotor. The second motor is mechanically connected to a second rotor comprising a second plurality of teeth radiating from the center of the first rotor, wherein the first plurality meshes with the second plurality. A sealed case may house the first and second rotors, and the case may include a suction inlet and a pressure outlet. Rotating the rotors propels a liquid from the suction inlet to the pressure outlet. Because the motors are independent of each other, when one motor fails to rotate the other motor will rotate both rotors and maintain the propelling liquid from the suction inlet to the pressure outlet. The pump may be a gear pump or a rotary lobe pump.

Abstract: A central distribution unit (CDU) for circulating coolant is disclosed. The CDU may operate under negative pressure and can have a number of operation modes including: normal operation, pump priming, fill, drain, purge and vacuum test. The CDU includes various valves, pumps and sensors, the placement and actuation of which transitions the CDU into the various modes.

Abstract: A sleep mask valve structure for treating a patient suffering from obstructive sleep apnea is provided. The valve structure includes a rigid valve housing comprising an inspiratory valve and an adjustable expiratory valve. The housing defines an outside mask side and an intra-mask side, and further defines an expiratory airflow conduit accommodating airflow from the intra-mask side to the outside mask side and an inspiratory airflow conduit accommodating airflow from the outside mask side to the intra-mask side. The expiratory airflow conduit includes at least two changes of direction, with each direction change greater than or equal to 75 degrees and the inspiratory airflow conduit includes comprising at least one change of direction greater than or equal to 75 degrees. The two paths share at least one change of direction.

Abstract: One or more battery-operated fans are integrated into a hard hat and pull air through a filter to remove contaminants in the air. The filtered air passes through one or more channels in the hard hat and exits the hard hat through an air curtain exit located near the user's face. The exiting air leaves with sufficient velocity to form an air curtain. A user wearing goggles or other protective eyewear will have the filtered air current pass in front of the eyewear. Paint and other contaminant particles that are in the air will not be able to contact the outer surface of the eyewear, as the particles will not be able to pass through the curtain of filtered air.

Abstract: A reliable, leak-tolerant liquid cooling system with a backup air-cooling system for computers is provided. The system may use a vacuum pump and a liquid pump and/or an air compressor in combination to provide negative fluid pressure so that liquid does not leak out of the system near electrical components. Alternatively, the system can use a single vacuum pump and a valve assembly to circulate coolant. The system distributes flow and pressure with a series of pressure regulating valves so that an array of computers can be serviced by a single cooling system. A connector system is provided to automatically evacuate the liquid from the heat exchangers before they are disconnected. Leah detection and mitigation structures are also disclosed. Various turbulators are also provided, as well as a system and method for optimizing the heat transfer characteristics of a heat exchanger to minimize total energy requirements.

Abstract: A hat includes a shell, and an air filtration system for providing a protective stream of air across the face of the wearer of the hat. The shell defines an exterior of the hat. At the back of the shell is a fan housing which contains a fan and defines an interior through which air is passed through the hat. The filtration system includes a filter cartridge and a retaining basket. The filter cartridge includes a filter medium. The filter system is removeably positioned adjacent to and across the fan housing so as to filter air passing into the interior of the hat. The filter cartridge is removeably engaged to the retaining basket. The retaining basket retains the cartridge to the hat and ensures proper positioning of the filter cartridge.

Abstract: One or more battery-operated fans are integrated into a hard hat and pull air through a filter to remove contaminants in the air. The filtered air passes through one or more channels in the hard hat and exits the hard hat through an air curtain exit located near the user's face. The exiting air leaves with sufficient velocity to form an air curtain. A user wearing goggles or other protective eyewear will have the filtered air current pass in front of the eyewear. Paint and other contaminant particles that are in the air will not be able to contact the outer surface of the eyewear, as the particles will not be able to pass through the curtain of filtered air.

Abstract: One or more battery-operated fans are integrated into a hard hat and pull air through a filter to remove contaminants in the air. The filtered air passes through one or more channels in the hard hat and exits the hard hat through an air curtain exit located near the user's face. The exiting air leaves with sufficient velocity to form an air curtain. A user wearing goggles or other protective eyewear will have the filtered air current pass in front of the eyewear. Paint and other contaminant particles that are in the air will not be able to contact the outer surface of the eyewear, as the particles will not be able to pass through the curtain of filtered air.

Abstract: One or more battery-operated fans are integrated into a hard hat and pull air through a filter to remove contaminants in the air. The filtered air passes through one or more channels in the hard hat and exits the hard hat through an air curtain exit located near the user's face. The exiting air leaves with sufficient velocity to form an air curtain. A user wearing goggles or other protective eyewear will have the filtered air current pass in front of the eyewear.

Abstract: A reliable, leak tolerant liquid cooling system with a backup air-cooling system for computers is provided. The system may use a vacuum pump and a liquid pump in combination to provide negative fluid pressure so that liquid does not leak out of the system near electrical components. The system distributes flow and pressure with a series of pressure regulating valves so that an array of computers can be serviced by a single cooling system. The system provides both air and liquid cooling so that if the liquid cooling system does not provide adequate cooling, the air cooling system will be automatically activated. A connector system is provided to automatically evacuate the liquid from the heat exchangers before they are disconnected.

Abstract: A reliable, leak-tolerant liquid cooling system with a backup air-cooling system for computers is provided. The system may use a vacuum pump and a liquid pump and/or an air compressor in combination to provide negative fluid pressure so that liquid does not leak out of the system near electrical components. Alternatively, the system can use a single vacuum pump and a valve assembly to circulate coolant. The system distributes flow and pressure with a series of pressure regulating valves so that an array of computers can be serviced by a single cooling system. The system provides both air and liquid cooling so that if the liquid cooling system does not provide adequate cooling, the air cooling system will be automatically activated. The heat may be removed from the building efficiently with a cooling tower. A connector system is provided to automatically evacuate the liquid from the heat exchangers before they are disconnected.

Abstract: A reliable, leak-tolerant liquid cooling system with a backup air-cooling system for computers is provided. The system may use a vacuum pump and a liquid pump and/or an air compressor in combination to provide negative fluid pressure so that liquid does not leak out of the system near electrical components. Alternatively, the system can use a single vacuum pump and a valve assembly to circulate coolant. The system distributes flow and pressure with a series of pressure regulating valves so that an array of computers can be serviced by a single cooling system. The system provides both air and liquid cooling so that if the liquid cooling system does not provide adequate cooling, the air cooling system will be automatically activated. The heat may be removed from the building efficiently with a cooling tower.

Abstract: An excavation system employing a high-pressure pulsed air jet that may optionally be used in combination with a low-pressure high velocity blower for excavating improvised explosive devices or other buried objects. The excavation system may also be employed to operate a pneumatic tool such as a cut-off tool or a chisel. The high velocity blower may incorporate a bifurcated fan duct having two air outlets. The system may include a pressure control module for regulating the from a high-pressure air source to an evacuation valve. The evacuation valve employs first and second valves where the second valve controls the operation of the first valve.

Abstract: A connector for use in a negative pressure coolant system is disclosed. The connector connects coolant system circulating to an electrical component thereby allowing the coolant to circulate through the electrical component. The connector is made up of two components, a component side connector and a pump side connector, and can be in three positions: disengaged, semi-engaged and fully-engaged. An electrical component can be drained of its coolant while the connector is shifted from the fully-engaged position, to the semi-engaged position and to the disengaged position. This can be accomplished without shutting down the negative pressure coolant system, thus allowing a particular electrical component to be disconnected without affecting the cooling efficiency of other electrical components connected to the system. Because the coolant is drained, it will not spill on the electrical component and cause damage.

Abstract: A connector for use in a negative pressure coolant system is disclosed. The connector connects coolant system circulating to an electrical component thereby allowing the coolant to circulate through the electrical component. The connector is made up of two components, a component side connector and a pump side connector, and can be in three positions: disengaged, semi-engaged and fully-engaged. An electrical component can be drained of its coolant while the connector is shifted from the fully-engaged position, to the semi-engaged position and to the disengaged position. This can be accomplished without shutting down the negative pressure coolant system, thus allowing a particular electrical component to be disconnected without affecting the cooling efficiency of other electrical components connected to the system. Because the coolant is drained, it will not spill on the electrical component and cause damage.