Exhaust gas-purifying device for internal combustion engines

In an exhaust gas-purifying device for an internal combustion engine having an exhaust passage, said exhaust gas-purifying device including adsorbing means arranged in said exhaust passage, for adsorbing unburnt fuel components in exhaust gases from said engine, purifying means arranged in said exhaust passage at a location downstream of said adsorbing means and having a catalyst for purifying components of said exhaust gases, and heater means for electrically heating said catalyst of said purifying means,

• the improvement comprising:
• adsorbing temperature-detecting means for detecting temperature of said adsorbing means;
• purifying temperature detecting means for detecting temperature of said purifying means;
• time period-measuring means for measuring a time period elapsed after said engine is started;
• and
• control means for causing said heater means to be operated when all of the following conditions are satisfied:
• 1) the temperature of said adsorbing means detected by said adsorbing temperature-detecting means is above a first predetermined value, 2) the temperature of said purifying means detected by said purifying temperature-detecting means is below a second predetermined value, and 3) the time period measured by said time period-measuring means falls within a predetermined time period.