Patent ID: 9255564
Filing Date: 2016-02-09
CPC Classification: F02D,F02P

Claim Text:
1. A glow plug drive control device comprising: an arithmetic and control unit that executes a drive control of a glow plug; and an energization drive circuit that performs energization of the glow plug in response to the drive control of the glow plug executed by the arithmetic and control unit, wherein the arithmetic and control unit is configured to arithmetically calculate a resistance value of the glow plug based on an energization current of the glow plug and a voltage applied to the glow plug, measure a heater reference point temperature, calculate an offset with a predetermined offset arithmetic expression based on the heater reference point temperature, perform a multiplication of a calculated resistance value of the glow plug and a predetermined constant based on an electrical characteristic of the glow plug, correct the multiplication result with the offset, and calculate an estimated temperature of a tip of the glow plug based on the corrected multiplication result, wherein the heater reference point temperature is the temperature of an arbitrary site excluding the neighborhood of a heating element of the glow plug, and the predetermined offset arithmetic expression is determined such that a value offsets a drift resulting from a change in the heater reference point temperature, and the predetermined constant based on the electrical characteristic of the glow plug is calculated as a function of the heater reference point temperature, and wherein the arithmetic and control unit is further configured to