| 摘要 |
PROBLEM TO BE SOLVED: To provide an air conditioning control panel from becoming a high temp. with current limiting resistors. SOLUTION: Three groups 57-59 in which one LED is sure to be lighted arc arranged in between a power source terminal 55 and a grounding terminal 56 in series. Consequently, a current is made to be sure to flow through first - third display groups 57-59 and since the first - third display groups 57-59 are arranged in series, a current flowing through a current limiting resistor R1 becomes smaller as compared with that in a conventional practice and also since the terminal voltage of the resistor R1 becomes smaller, a calorific value in the resistor R1 is reduced. As a result, the deformation of a frame body 51 due to heats of current limiting resistors R1-R4 is prevented from being generated-Moreover, current limiting resistors become four pieces of the R1-R4, the number of resistors are reduced as compared with that in the conventional practice. Thus, the number of components is reduced and also power consumptions in the current limiting resistors R1-R4 are more reduced and the caloric value of a device is reduce. |
