Abstract: A microfluidic bubble fuse is formed from a hermetically sealed reservoir containing an electrically conductive liquid. The reservoir is interposed between a pair of electrodes such that each electrode is in electrical contact with the fluid within the reservoir, and such that the fluid within the reservoir provides electrical interconnectivity between the electrodes. The reservoir may be implemented on a substrate, in a tube, or in another manner. When the current or voltage across the electrodes increases beyond a threshold, the excess current or voltage will cause a bubble to be created within the fluid to reduce or inhibit the flow of electricity between the electrodes. When the current/voltage is reduced, the bubble will collapse to restore the flow of electricity between the electrodes.

Abstract: An electric switch for thermal overload protection includes a meltable pellet containing a pool of mercury which establishes electrical contact between two lead-in wires. When the pellet is heated to its melting point, the mercury becomes unconfined and the circuit is opened.

Abstract: A space thermostat for controlling the two-stage operation of both heating and cooling apparatus includes two single-pole, double-throw mercury type switches operatively connected to a single bimetallic coil. One switch energizes stage one of the heating apparatus when tilted in one direction and energizes stage two of the cooling apparatus when tilted in the other direction. The other switch energizes stage two of the heating apparatus when tilted more in the direction which effected the energizing of stage one of the heating apparatus and energizes stage one of the cooling apparatus when tilted less in the direction which effected the energizing of stage two of the cooling apparatus. The switches are adjustably mounted with respect to each other so that the differential between stages can be adjusted to be the same as the differential of each switch.

Abstract: A thermostat having a cover plate rotatable about a central horizontal support in which a bimetal or other thermally responsive member supported on the cover plate actuates a mercury switch also on the cover plate. This cover plate also has upon it indicia such as degree marks or simply arrows indicating "colder -- warmer" operable against an imaginary vertical lubber line to indicate a setting. The need for time consuming and expensive levelling of the thermostat during installation is thus obviated because the thermostat is automatically levelled by the user as a result of setting the indicia in relation to the imaginary vertical line.

Abstract: A temperature-sensitive tipswitch includes a pair of normally closed flexible conductive arms. A temperature responsive actuating arm is mounted adjacent the conductive arms and insulation discs separate all three. A bracket is connected into the stack formed by the arms and insulation discs and the bracket mounts a mercury tipswitch. There are one or more terminals extending out from the stack and in electrical contact with one of the conductive arms and a second terminal connected to the tipswitch.