Abstract: A heat storage unit (100) in the form of a rectangular parallelepiped is provided with a removable closure element (104), and contains a plurality of removable closed plastic tubes (126) holding a heat storage substance, the tubes being laterally supported by adjacent tubes and longitudinally supported to be spaced from ends of the unit by grids (124a and b). A transfer fluid flows from one end of the unit to the other through spaces between the tubes. A heat storage system (FIGS. 4 or 5 for example) is conveniently custom built by attaching a plurality of the rectangular parallelepiped units to form a cluster of units. Each unit includes a special structural frame (106) to allow such attaching. The units contain heat storage substances of various adjustable melting temperatures, thereby providing for the storing of heat as the latent heat of fusion at several temperature levels.

Abstract: A method and apparatus for converting temperature differentials to usable energy employs a crystalline fusible material (47) having a fusion temperature in the range of from 70.degree. to 120.degree.. The fusible material (47) is mounted inside a cylinder housing (26) for driving a piston (22) therein as the fusible material (47) is alternately frozen and thawed by warm and cool fluid which is alternately circulated around and through the cylinder housing (26). The cool fluid is obtained from an unrefrigerated, ambient cool water source, such as tap water, ground water, evaporative cooler, or the like. Warm fluid is obtained from waste heat, solar heat, etc. In this system, a fine control is provided to insure that the crystalline fusible material (47) does not totally freeze or thaw, but rather remains in a transient state at all times. The piston (22) is linked to a hydraulic accumulator (12) for creating and maintaining hydraulic pressure.

Abstract: A selective extraction heat storage assembly (32) for use in a system including a plurality of such assemblies (32a-c) and for use by itself, includes a heat unit (10) connected in parallel with a fluid circulating passage (54) and has a separate unit heat extractor (exchanger) (34) mounted in the unit (10). The unit (10) can be charged and discharged by fluid flow through the unit caused by an outside fluid circuit and can be similarly discharged thereby. However, in addition, the unit can be charged and discharged by means of the separate unit heat extractor (exchanger) (34) within the unit by closing off the heat storage assembly from the outside fluid circuit and circulating fluid through the unit via the parallel fluid circulating passage (54). A pump (42), several sensors (46 and 52), and valves (44 and 60) form a part of the heat storage assembly to provide for this operation.

Abstract: A hand held gas detector comprises a flexible, transparent, resilient container provided with inlet and outlet valves at opposing ends for controlling flow through inlet and outlet ports, the valves being controlled by the pressure within the container relative to the ambient pressure so that one valve is closed as the other is opened. The container is partially filled with a detector fluid which changes color upon being contacted by the gas being tested for. The container is repetitively squeezed and released to alternately draw ambient atmosphere through the inlet valve into the detector fluid, and exhaust gases in the container back into the atmosphere. The detector liquid returns to its original color in the absence of contact with the gas being detected, hence the device is reusable.

Abstract: A heat storage unit in the form of a cylinder is provided with a removable end closure, and contains a plurality of closed tubes holding a heat storage substance, the tubes being supported at either end thereof by screens. A transfer fluid flows from one end of the cylinder to the other between tubes for transfer of heat. A heat storage system is provided by the combination of a plurality of units, the units containing heat storage substances of various melting temperatures, thereby providing for the storing of heat as the latent heat of fusion at several temperature levels.