THERMAL DRIVE Russian patent published in 1999 - IPC

FIELD: automatic maintenance of specified temperature conditions in rooms, greenhouses, hotbeds thanks to natural ventilation. SUBSTANCE: as distinct from traditional thermal drive including support, shaft with lever mounted for rotary motion and temperature-sensitive element in the form of cylindrical tubular spring filled with liquid mentioned temperature-sensitive element is manufactured in the form of multilayer screw cylindrical tubular spring having number of layers multiple of two. Direction of lay of even layers is opposite to that of odd layers. One end of this spring is made fast to support and the other end - to lever. Apart from this form and dimensions of cross-section of turns of spring are so made that provide for same flexural rigidity for all turns. EFFECT: low sluggishness, high accuracy in keeping of preset temperature, small size and mass and reliable operation of proposed thermal drive. 1 cl, 2 dwg