| JP2008008181 | DIESEL ENGINE |
| JPS6041225 | [Title of the Invention] Exhaust gas re-circulation system |
| WO/2009/060866 | EXHAUST PURIFICATION DEVICE FOR HYBRID ELECTRIC AUTOMOBILE |
RAJASEKARAN D (IN)
KARTHIKEYAN E M (IN)
SHANKAR V (IN)
RAJASEKARAN D (IN)
KARTHIKEYAN E M (IN)
| DE2448151A1 | 1975-04-17 | |||
| JPS52134924A | 1977-11-11 | |||
| JP2006090200A | 2006-04-06 |
Claims
1. An exhaust gas recirculation (EGR) valve for recirculating engine's exhaust gases comprises an actuator having top cover (15), compression spring (14), diaphragm (3); wherein gasket diaphragm (12) placed below the top portion of the diaphragm (3) acts as temperature seal, a steel washer-big (8) is placed in between two gasket-big (1 1) to avoid temperature being conducted to the diaphragm (3), and a combination of gasket-small (10), cup-washer (13), steel washer-small (9) are placed on the either sides of the diaphragm (3) for supporting the diaphragm (3);wherein the gasket small acts as a temperature seal ; a body having inlet hole for receiving exhaust gases and outlet hole for delivering the exhaust gases; and a valve mechanism comprising a valve (6) that is positionable along an axis relative to valve seat (2) to control the flow of the exhaust gases from the inlet hole to the outlet hole, a valve body (1) to mount the annular bush (4) along the axis relative to valve seat (2) to guide a shaft (7) movement, wherein the shaft (7) is connected to the diaphragm (3) of the actuator by means of a nut (17) at one end and passed through the annular bush (4) and orbital riveted to the valve (6) at other end ; a gasket seal (18) placed in between the shaft (7) and steel washer-small (9) acts as a temperature seal.
2. The exhaust gas recirculation valve as claimed in claim 1, wherein the top cover
(15) has a port for vacuum supply and is made from plastic material Glass filled Polybutylene Terephthalate (PBT).
3. The exhaust gas recirculation valve as claimed in claim 1, wherein the diaphragm (3) is made from FKM material with fabric reinforcement.
4. The exhaust gas recirculation valve as claimed in claim 1, wherein the top portion of the diaphragm (3) is connected to the valve body (1) and the bottom portion is connected to the shaft (7).
5. The exhaust gas recirculation valve as claimed in claim 1, wherein the valve body (1) has an axially extending way leading to inlet hole and a transverse way leading to outlet hole.
6. The exhaust gas recirculation valve as claimed in claim 1, wherein the valve seat (2) is press fitted to the to the inlet hole of the valve body (1) and is fixed by dowel pin (16) to arrest movement of the valve seat (2) due to various forces acting on the valve seat and temperature effect.
7. The exhaust gas recirculation valve as claimed in claim 1, wherein the actuator unit and the valve body (1) are integrated as a single product.
8. The exhaust gas recirculation valve as claimed in claim 1, wherein the gasket- small (10), the cup-washer (13), Gasket seal (18) and the steel washer-small (9) are sandwiched and bolted to the shaft (7) by a nut (17) for supporting the diaphragm (3).
9. The exhaust gas recirculation valve as claimed in claims 1, wherein the diaphragm (3), gasket big (11) and steel washer-big (8) are sandwiched and locked by cover crimping (5) between valve body (1) and top cover (15).
10. The exhaust gas recirculation valve as claimed in claim 1, wherein the compression spring (14) is seated above the cup washer (13) and the other end is guided by the top cover (15).
11. The exhaust gas recirculation valve as claimed in claim 1, wherein the cup washer (13) is provided to avoid damages to diaphragm (3) by the compression spring (14).
12. A method of recirculating engine's exhaust gases using an exhaust gas recirculation valve of claim 1, wherein said method comprises applying vacuum pressure through the vacuum port of the top cover (15) to move diaphragm (3) upwards which in turn lifts up the shaft (7) attached to it; and actuates the valve (6) to open for allowing the exhaust gases to pass through the valve (6) from inlet hole to outlet hole.
13. The method as claimed in claim 12, wherein the operating vacuum ranges from -150 mm of Hg to -600 mm of Hg.
14. The method as claimed in claim 12, wherein the operating stroke ranges from 6 mm to 12 mm preferably 8.5mm.
15. The method as claimed in claim 12, wherein the flow rate of recirculation ranges from 35 m 3 /hr to 70m 3 /hr preferably 48m 3 /hr.
16. A method of assembling an exhaust gas recirculation (EGR) valve as claimed in claim 1 comprising steps of connecting the shaft (7) to the diaphragm (3) of the actuator at one end by means of a nut (17) and passing through the annular bush (4) and orbital riveting to the valve (6) at other end. |
EXHAUST GAS RECIRCULATION VALVE
Technical Field
The present invention relates to Exhaust Gas Recirculation (EGR) Valve. Particularly the EGR valve is the main emissions control component in the exhaust gas recirculation system. The EGR valve is opened by the application of vacuum/ pressure to its control diaphragm. The opening and closing of the EGR valve and the amount of recirculation of exhaust gas depends on the engine design.
Background
Exhaust gas recirculation (EGR) is a NOx (nitrogen oxide and nitrogen dioxide) reduction technique used in most gasoline and diesel engines.
EGR works by recirculating a portion of an engine's exhaust gas back to the engine cylinders. Mixing the incoming air with recirculated exhaust gas dilutes the mix with inert gas, lowering the adiabatic flame temperature and (in diesel engines) reducing the amount of excess oxygen. The exhaust gas also increases the specific heat capacity of the mix lowering the peak combustion temperature. Because NOx formation progresses much faster at high temperatures, EGR serves to limit the generation of NOx. NOx is primarily formed when a mix of nitrogen and oxygen is subjected to high temperatures.
Summary of the Invention
Accordingly the invention provides for an exhaust gas recirculation (EGR) valve for recirculating engine's exhaust gases comprises an actuator having top cover (15), compression spring (14), diaphragm (3); wherein gasket diaphragm (12) placed below the top portion of the diaphragm (3) acts as temperature seal, a steel washer-big (8) is placed in between two gasket-big (11) to avoid temperature being conducted to the diaphragm (3), and a combination of gasket-small (10), cup-washer (13), steel washer- small (9) are placed on the either sides of the diaphragm (3) for supporting the diaphragm (3); wherein the gasket small acts as a temperature seal, a body having inlet hole for receiving exhaust gases and outlet hole for delivering the exhaust gases; and a valve mechanism comprising a valve (6) that is positionable along an axis relative to
valve seat (2) to control the flow of the exhaust gases from the inlet hole to the outlet hole, a valve body (1) to mount the annular bush (4) along the axis relative to valve seat
(2) to guide a shaft (7) movement, wherein the shaft (7) is connected to the diaphragm
(3) of the actuator by means of a nut (17) at one end and passed through the annular bush (4) and orbital riveted to the valve (6) at other end; a gasket seal (18) placed in between the shaft (7) and steel washer-small (9) acts as a temperature seal. A method of recirculating engine's exhaust gases using an exhaust gas recirculation valve, wherein said method comprises applying vacuum pressure through the vacuum port of the top cover (15) to move diaphragm (3) upwards which in turn lifts up the shaft (7) attached to it; and actuates the valve (6) to open for allowing the exhaust gases to pass through the valve (6) from inlet hole to outlet hole.
A method of assembling an exhaust gas recirculation (EGR) valve comprising steps of connecting the shaft (7) to the diaphragm (3) of the actuator at one end by means of a nut (17) and passing through the annular bush (4) and orbital riveting to the valve (6) at other end.
Brief Description of the Drawings
Fig.l is a diagrammatic illustration of an EGR valve, wherein it provides for the cross section of the EGR valve.
Fig.2 is diagrammatic illustration of the Actuator Part of the EGR valve.
Detailed Description of the Invention
Fig. l illustrates the cross section of the Exhaust Gas Recirculation Valve. The valve is located near the intake manifold, of an automobile and opens a small passageway between the exhaust and intake manifold to allow a metered amount of exhaust to flow back into the engine. This reduces combustion temperatures and helps to control the formation of oxides of nitrogen.
The EGR valve is opened by the application of vacuum/ pressure to its control diaphragm. The opening and closing of the EGR valve and the amount of recirculation of exhaust gas depends on the engine design.
Fig.2 illustrates the cross section of the actuator unit.
The present invention is in relation to an Exhaust Gas Recirculation (EGR) Valve, wherein the EGR valve comprises an actuator having top cover (15), compression spring (14), diaphragm (3); wherein gasket diaphragm (12) placed below the top portion of the diaphragm (3) acts as temperature seal, a steel washer-big (8) is placed in between two gasket-big (11) to avoid temperature being conducted to the diaphragm (3), and a combination of gasket-small (10), cup-washer (13), steel washer-small (9) are placed on the either sides of the diaphragm (3) for supporting the diaphragm (3), wherein the gasket small acts as a temperature seal ; a body having inlet hole for receiving exhaust gases, and outlet hole for delivering the exhaust gases; and a valve mechanism comprising a valve (6) that is positionable along an axis relative to valve seat (2) to control the flow of the exhaust gases from the inlet hole to the outlet hole, a valve body (1) to mount the annular bush (4) along the axis relative to valve seat (2) to guide a shaft (7) movement, wherein the shaft (7) is connected to the diaphragm (3) of the actuator by means of a nut (17) at one end and passed through the annular bush (4) and orbital riveted to the valve (6) at other end; a gasket seal (18) placed in between the shaft (7) and steel washer -small (9) acts as a temperature seal.
In yet another embodiment of the present invention the top cover (15) has a port for vacuum supply and is made from plastic material Glass filled Polybutylene Terephthalate (PBT).
In still another embodiment of the present invention the diaphragm (3) is made from
FKM material with fabric reinforcement.
In still another embodiment of the present invention the top portion of the diaphragm (3) is connected to the valve body (1) and the bottom portion is connected to the shaft (7).
In still another embodiment of the present invention the valve body (1) has an axially extending way leading to inlet hole and a transverse way leading to outlet hole.
In still another embodiment of the present invention the valve seat (2) is press fitted to the to the inlet hole of the valve body (1) and is fixed by dowel pin (16) to arrest movement of the valve seat (2) due to various forces acting on the valve seat and temperature effect.
In still another embodiment of the present invention the actuator unit and the valve body (1) are integrated as a single product.
In still another embodiment of the present invention the gasket-small (10), the cup- washer (13), Gasket seal (18) and the steel washer-small (9) are sandwiched and bolted to the shaft (7) by a nut (17) for supporting the diaphragm (3).
In still another embodiment of the present invention the diaphragm (3), gasket big (1 1), and steel washer-big (8) are sandwiched and locked by cover crimping (5) between valve body (1) and top cover (15).
In still another embodiment of the present invention the compression spring (14) is seated above the cup washer (13) and the other end is guided by the top cover (15).
In still another embodiment of the present invention the cup washer (13) is provided to avoid damages to diaphragm (3) by the compression spring (14).
In still another embodiment of the present invention a method of recirculating engine's exhaust gases using an exhaust gas recirculation valve, wherein said method comprises applying vacuum pressure through the vacuum port of the top cover (15) to move diaphragm (3) upwards which in turn lifts up the shaft (7) attached to it; and actuates the valve (6) to open for allowing the exhaust gases to pass through the valve (6) from inlet hole to outlet hole.
In still another embodiment of the present invention the operating vacuum ranges from -150mm of Hg to -600mm of Hg.
In still another embodiment of the present invention the operating stroke ranges from 6 mm to 12 mm preferably 8.5 mm.
In still another embodiment of the present invention the flow rate of recirculation ranges from 35m 3 /hr to 70m 3 /hr preferably 48m 3 /hr.
In still another embodiment of the present invention a method of assembling an exhaust gas recirculation (EGR) valve comprising steps of connecting the shaft (7) to the diaphragm (3) of the actuator at one end by means of a nut (17) and passing through the annular bush (4) and orbital riveting to the valve (6) at other end.
Industrial Applicability:
The disclosed exhaust gas recirculation valve potential application in any exhaust gas recirculation system. The disclosed exhaust gas recirculation valve finds particular applicability in automotives, especially in most gasoline and diesel engines.
The exhaust gas recirculation valve is the main emission control component in the exhaust gas recirculation system. The valve is located near the intake manifold, and opens a small passageway between the exhaust manifold and intake manifold to allow a metered amount of exhaust gases to flow back into the engine. This reduces combustion temperatures and helps to controlling the formation of oxides of nitrogen (NOx).
Referring Fig.2, the exhaust gas recirculation valve is opened by the application of vacuum to its control diaphragm. The opening and closing of the exhaust gas recirculation valve and the amount of recirculation of exhaust gas depends on the engine design.
The advantages of integrating the actuator unit with valve unit are, the exhaust gas recirculation valve occupies less space, the response time of the valve is reduced, and complicated linkages between valve unit and the actuator unit is avoided which increases reliability. The top cover (15) of the actuator unit is made up of plastic material (PBT) which has advantages of low cost, low density, and ease of machining. The gaskets at the interfaces between diaphragm (3) and the metal parts acts as thermal barrier, it prevents the conduction of heat from valve body (1) to the diaphragm (3), and also prevents the conduction of heat from shaft (7) to the diaphragm (3). The crimping process during assembly has some advantages like no fasteners are required for joining valve and the actuator, and time required for the assembly is reduced.
It will be apparent to those skilled in the art that various modifications and variations can be made to the exhaust gas recirculation valve of the present disclosure. Other
embodiments of the exhaust gas recirculation valve will be apparent to those skilled in the art from consideration of the specification of the valve disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
LIST OF ELEMENTS
TITLE: EXHAUST GAS RECIRCULATION VALVE
1. VALVE BODY
2. VALVE SEAT
3. DIAPHRAGM
4. BUSH
5. COVER CRIMPING 6. VALVE
7. SHAFT
8. STEEL WASHER-BIG
9. STEEEL WASHER-SMALL
10. GASKET SMALL 1 1. GASKET BIG
12. GASKET - DIAPHRAGM
13. CUP WASHER
14. SPRING
15. TOP COVER 16. DOWEL PIN
17. NUT
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