Abstract: Inside a tight sealed chamber defined between a rim and a tire of a pneumatic tire wheel for vehicles, there is provided a predetermined amount of a two-phase system in a substantially balanced state at the tire temperature and inflation pressure. The two-phase system comprises a liquid in a balanced state with its own vapor contained within a sealed, elastically deformable toric bladder which is mounted to the rim. By changing the amount of heat in the two-phase system so as to change its balance condition, a variation is obtained in the inflation pressure of the tire.

Abstract: A structure for an easy chair, sofa, or the like, which affords improved comfort and a simple construction, comprises a plurality of deformable sealed blisters containing a fluid having a set boiling temperature, such as a Freon, and electric resistance heaters associated with said blisters to vary the fluid temperature and, hence, the blister volumes and pressures.

Abstract: A padding element for protection against shocks, particularly useful with a crash helmet, which confers on the helmet unusual adaptability to the user's head, comprises at least one deformable vesicle containing a fluid which, in use of the padding element, is a saturated vapor state, a Peltier-effect thermoelectronic component having a face in contact with a surface section of said at least one vesicle, and a power supply for supplying an electric current in either directions to said component, so as to either develop or absorb heat from said face and adjust the vesicle internal pressure.

Abstract: A padding element suitable for use in a crash helmet having a plurality of padding elements including a plurality of first deformable blisters interconnected together in sets, and containing a fluid which is in a saturated vapor state when the helmet has been worn for a sufficient time to raise its fluid temperature to a temperature approaching normal body temperature. It is contemplated that the fluid contained in the first deformable blisters preferably includes a mixture of Freon MF and Freon TF with the proportion of Freon MF being in the range of 20% to 50% by volume liquid.

Abstract: An actuator comprises an impervious deformable bladder containing a fluid whose boiling temperature is equal to a set cut-in temperature. On reaching that temperature, the fluid within the bladder will be vaporized, cause the bladder to expand, and produce accordingly a displacement movement which can be utilized for a variety of purposes.