Abstract: A temperature-controlled environmental chamber includes a resistance heater controlled by a solid state relay and a refrigeration unit including an electronically controlled suction throttling valve connected in the refrigerant line between the evaporator and the inlet of the compressor. A temperature controller senses the temperature in the chamber and compares it to a set point temperature and outputs a pulse-width modulated control signal indicative of the difference between the two temperatures. The control signal directly controls the heater relay for substantially continuous variation between minimum and maximum heating conditions. The control signal is converted to an analog signal for controlling the throttling valve of the refrigeration unit for substantially continuous variation between maximum and minimum cooling conditions, so that the amount of cooling provided is inversely proportional to the amount of heating provided.

Abstract: An implement includes first and second elongated legs that are joined by a first hinge between respective one ends thereof to permit those legs to be folded toward and away from one another. The legs are mutually shaped to define a cavity within a handle when folded together about the hinge. Third and fourth elongated legs are each of a size to be nested within the portion of the cavity defined by a respective one of the first and second legs. A second hinge couples one end of the third leg to the other end of the first leg. A third hinge couples one end of the fourth leg to the other end of the second leg. Finally, a fourth hinge couples together the other ends of the third and fourth legs.

Abstract: A multiple-compartment container is formed from an elongated sleeve of flexible material. Opposing end portions of the sleeve are respectively sealed together. A third seal of the walls of the sleeve, at a location spaced between those end portions, defines first and second hollow compartments respectively on each side of that third seal. The third seal is effected by a twisting of the sleeve about its longitudinal axis. There is illustrated a still further and preferred fourth seal at a location spaced between the third seal and one of the end portions so as to define a still further hollow compartment, and that additional seal also is effected by a twisting of the sleeve.