Electronic thermostat

Abstract

An electronic thermostat apparatus for controlling a temperature of a coolant of an engine in a vehicle may include a housing connected to a plurality of flow paths through which the coolant of the engine flows, a wax case installed inside the housing and provided with a wax accommodation space therein, a glow plug heater inserted in a wax filled inside the wax accommodation space and configured to generate heat by receiving an external power, a driving body engaged to the wax case and moving according to deformation of the wax by the heat of the glow plug heater, a main valve engaged to the driving body and configured to open/close a radiator-side flow path by a movement of the driving body, and an elastic member elastically biasing the main valve to the radiator-side flow path.

What is claimed is: 
     
         1 . An electronic thermostat apparatus for controlling a temperature of a coolant of an engine in a vehicle, the electronic thermostat apparatus comprising:
 a housing connected to a plurality of flow paths through which the coolant of the engine flows;   a wax case installed inside the housing and provided with a wax accommodation space therein;   a glow plug heater inserted in a wax filled inside the wax accommodation space and configured to generate heat by receiving an external power;   a driving body engaged to the wax case and moving according to deformation of the wax by the heat of the glow plug heater;   a main valve engaged to the driving body and configured to open/close a radiator-side flow path by a movement of the driving body; and   an elastic member elastically biasing the main valve to the radiator-side flow path.   
     
     
         2 . The electronic thermostat apparatus of  claim 1 , further including:
 a bypass valve coupled to the driving body and configured to open/close a bypass flow path that does not circulate through a radiator while interworking with the main valve.   
     
     
         3 . The electronic thermostat apparatus of  claim 1 , wherein the electronic thermostat apparatus is installed at an inlet of the engine through which the coolant flows in the engine or an outlet of the engine through which the coolant is discharged from the engine. 
     
     
         4 . The electronic thermostat apparatus of  claim 1 , wherein the glow plug heater includes a cylindrical case, a heating tube coupled to one end of the case, a coil installed inside the heating tube, and an insulation member filled in a space between the coil and the heating tube. 
     
     
         5 . The electronic thermostat apparatus of  claim 4 , wherein the coil includes a heating coil configured to generate the heat or a temperature adjusting coil configured to control an increase in a temperature of the heating coil. 
     
     
         6 . The electronic thermostat apparatus of  claim 4 , wherein the insulation member is made of magnesium oxide (MgO) powder. 
     
     
         7 . The electronic thermostat apparatus of  claim 1 , wherein a transmission fluid is disposed between the wax and the driving body in a cylindrical element guide connected to the wax case. 
     
     
         8 . The electronic thermostat apparatus of  claim 7 , wherein a rubber moving body is disposed between the transmission fluid and the driving body. 
     
     
         9 . The electronic thermostat apparatus of  claim 7 , wherein an inner diameter of a cylindrical frame receiving the wax case is larger than an inner diameter of a cylindrical element guide slidably receiving the driving body. 
     
     
         10 . An electronic thermostat apparatus for cooling a temperature of a coolant of an engine in a vehicle, the electronic thermostat apparatus employing a glow plug heater that heats a wax. 
     
     
         11 . The electronic thermostat apparatus of  claim 10 , wherein the glow plug heater includes:
 a cylindrical case;   a heating tube coupled to one end of the case;   a coil installed inside the heating tube; and   an insulation member filled in a space between the coil and the heating tube.   
     
     
         12 . The electronic thermostat apparatus of  claim 11 , wherein the coil includes a heating coil configured to generate heat or a temperature adjusting coil configured to control an increase in a temperature of the heating coil. 
     
     
         13 . The electronic thermostat apparatus of  claim 11 , wherein the insulation member is made of magnesium oxide (MgO) powder. 
     
     
         14 . The electronic thermostat apparatus of  claim 11 , wherein a transmission fluid is disposed between the wax disposed in the cylindrical case and a driving body disposed in a cylindrical element guide connected to a wax case containing the wax. 
     
     
         15 . The electronic thermostat apparatus of  claim 14 , wherein a rubber moving body is disposed between the transmission fluid and the driving body. 
     
     
         16 . The electronic thermostat apparatus of  claim 14 , wherein an inner diameter of a frame receiving the wax case is larger than an inner diameter of the cylindrical element guide