PURPOSE: To perform simply and inexpensively highly accurate temperature correction in accordance with the difference of the specific gravity of LPG, by varying the actuation rate to a variable speed gear by adjusting the position of a temperature-displacement conversion part in accordance with the properties of liquid.

CONSTITUTION: A rotary sliding plate 19 is supported with a pin 18 of a base board 16 and a temperature-displacement conversion part 20 provided with a temperature sensitive tube 13 is fixed piercing into the plate 19. The plate 19 is attached to a long hole 21 with a lock screw 23. A rotating lever 27 is abutted to a spindle 20a of the part 20 and an actuation element 10a of a variable speed gear 10. Now, when the temperature of LPG is varied, the spindle 20 is actuated and the temperature correction is carried out through the lever 27 by varying the rate of the variable speed of the gear 10. In case the specific gravity of the LPG is different, the plate 19 is approached to an axis 26 and the turning of the lever 27 is made quick at the time when the specific gravity is small and it is actioned reversely at the time when the specific gravity is large. For this reason, the correction of the specific gravity is performed by varying the turning angle of the lever 27 and varying the actuation rate of the gear 10 corresponding to the dimensions of the specific gravity. Hereby, highly accurate temperature correction is performed in accordance with the difference of the specific gravity.