Back to results
US 10,378,424 B2Granted
Exhaust gas recirculation system
AssigneeDenso Corporation
InventorsToru Okamura, Kenichi Nara
Life of this patent
Estimating the term…
Abstract
The exhaust gas recirculation system comprises an exhaust recirculation pipe configured to recirculate an exhaust gas from an engine into an intake pipe of the engine, an exhaust gas heat exchanger connected to the exhaust recirculation pipe and configured to perform an heat exchange between the exhaust gas and an engine cooling water used for cooling the engine, a cooling water pipe configured to circulate the engine cooling water to the exhaust gas heat exchanger, and a heat insulating member forming a heat insulating layer on a heat transfer path from the exhaust gas heat exchanger to the outside.
Claims10
An exhaust gas recirculation system, comprising:
- an exhaust recirculation pipe configured to recirculate an exhaust gas from the engine into an intake pipe of the engine;
- an exhaust gas heat exchanger connected to the exhaust recirculation pipe and configured to perform a heat exchange between the exhaust gas and an engine cooling water used for cooling the engine;
- a cooling water pipe configured to circulate the engine cooling water to the exhaust gas heat exchanger;
- and
- a heat insulating member forming a heat insulating layer on a heat transfer path from the exhaust gas heat exchanger to the outside, wherein
- the exhaust gas heat exchanger includes,
- a plurality of tubes through which the exhaust gas passes,
- a casing in which the tubes are housed, the casing including an inlet side flange and an outlet side flange,
- a cooling water flow path provided inside of the casing, through which the cooling water that exchanges heat with the exhaust gas flowing through the tubes passes, wherein
- the inlet side flange is configured to transfer heat to the casing and divide the exhaust gas to the plurality of tubes, and
- the outlet side flange is configured to transfer heat to the casing and collect the exhaust gas passed through the plurality of tubes,
- the exhaust recirculation pipe includes an upstream flange for connecting to the inlet side flange, and a downstream flange for connecting to the outlet side flange,
- the heat insulating member includes,
- an inlet side heat insulating member covers an inner peripheral edge and an outer peripheral edge of a connecting surface of the inlet side flange so as to have a heat insulating function and a sealing function, and
- an outlet side heat insulating member covers an inner peripheral edge and an outer peripheral edge of a connecting surface of the outlet side flange so as to have a heat insulating function and a sealing function.
12 more elements
An exhaust gas recirculation system, comprising:
- an exhaust recirculation pipe configured to recirculate an exhaust gas from the engine into an intake pipe of the engine;
- an exhaust gas heat exchanger connected to the exhaust recirculation pipe and configured to perform a heat exchange between the exhaust gas and an engine cooling water used for cooling the engine;
- a cooling water pipe configured to circulate the engine cooling water to the exhaust gas heat exchanger;
- and
- a heat insulating member forming a heat insulating layer on a heat transfer path from the exhaust gas heat exchanger to the outside, wherein
- the exhaust gas heat exchanger includes,
- a plurality of tubes through which the exhaust gas passes,
- a casing in which the tubes are housed, the casing including an inlet side flange and an outlet side flange,
- a cooling water flow path provided inside of the casing, through which the cooling water that exchanges heat with the exhaust gas flowing through the tubes passes, wherein
- the inlet side flange is configured to transfer heat to the casing and divide the exhaust gas to the plurality of tubes,
- the outlet side flange is configured to transfer heat to the casing and collect the exhaust gas passed through the plurality of tubes,
- a water inlet pipe provided on the inlet flange side in the casing, and
- a water outlet pipe provided on the outlet flange side in the casing,
- the heat insulating member is a case heat insulating member configured to cover an outer periphery of the casing except for the water inlet pipe and the water outlet pipe.
11 more elements
An exhaust gas recirculation system, comprising:
- an exhaust recirculation pipe configured to recirculate an exhaust gas from the engine into an intake pipe of the engine;
- an exhaust gas heat exchanger connected to the exhaust recirculation pipe and configured to perform a heat exchange between the exhaust gas and an engine cooling water used for cooling the engine;
- a cooling water pipe configured to circulate the engine cooling water to the exhaust gas heat exchanger;
- and
- a heat insulating member forming a heat insulating layer on a heat transfer path from the exhaust gas heat exchanger to the outside,
- a cooling water temperature sensor configured to measure a temperature of the engine cooling water,
- a heat storage device provided in a downstream side of the cooling water temperature sensor, and being configured to perform heat storage and heat radiation by exchanging heat with the engine cooling water,
- a control device configured to control heating by the heat storage device based on the temperature of the engine cooling water measured by the cooling water temperature sensor, and
- a bypass pipe configured to circulate the engine cooling water not through the heat storage device by communicating the inlet pipe of the heat storage device and the outlet pipe thereof, wherein
- the control device performs a heat storage mode
- when the engine cooling water is lower than a predetermined temperature during the exhaust gas recirculation, the engine cooling water is heated by flowing the engine cooling water to the heat storage device, and when the engine cooling water is higher than the predetermined temperature, the engine cooling water flows through the bypass pipe so as not to pass through the heat storage device, and
- when the exhaust gas recirculation is not performed and the engine cooling water is higher than the predetermined temperature, heat is accumulated in the heat storage device by flowing the engine cooling water into the heat storage device.
9 more elements
Dependencies are inferred from the claim text.