Particulate matter sensor and exhaust gas purification system using the same

An exhaust gas purification system, comprising:

• an exhaust manifold;
• an exhaust gas particle filter configured to remove particles included in an exhaust gas from the exhaust manifold;
• and
• a particulate matter sensor arranged on an exhaust pipe connected to the exhaust gas particle filter and configured to sense particulate matter flowing to a downstream side through the exhaust gas particle filter, wherein
• the particulate matter sensor includes first, second, third, and fourth insulation layers laminated together,
• the first insulation layer including a first electrode unit on a first side thereof, the first electrode unit exposed to particulate matter during operation of the particulate matter sensor, and the first electrode unit including a plurality of first electrodes not electrically connected to each other,
• the second insulation layer arrange in parallel to the first insulation layer with a space therebetween, the second insulation layer including a second electrode unit on a first side thereof that faces a second side of the first insulation layer opposite the first side of the first insulation layer such that the second electrode unit is not exposed to particulate matter during operation of the particulate matter sensor, the second electrode unit including a plurality of second electrodes electrically connected to each other,
• a temperature sensing unit formed on a first side of the third insulation layer located on a second side of the second insulation layer, and
• a heater unit formed on a first side of the fourth insulation layer located on a second side of the third insulation layer, the heater unit configured to heat the first and second electrode units, wherein
• each of the plurality of second electrodes is spaced apart from a lower portion of the plurality of the first electrodes so as to overlap and correspond to each other with each of the plurality of the first electrodes,
• the plurality of first electrodes are electrically connected to each other by the particulate matter deposited in a space formed between two neighboring first electrodes, and
• a capacitance between the first electrodes and the second electrodes is increased by enlarging an area of the first electrodes electrically connected to each other when the particulate matter is deposited between the first electrodes.