Claims:1. A fuel injected single cylinder naturally aspirated diesel engine (10), said fuel injected single cylinder naturally aspirated diesel engine (10) comprising:
an engine (12);
an air suction valve adapted to be coupled to an inlet of said engine (12);
a hot-film mass air-flow sensor (14) positioned upstream from said engine (12);
a unidirectional flow control valve (16) positioned between said hot-film mass air-flow sensor (14) and said air suction valve, characterized in that
said unidirectional flow control valve (16) comprising:
a chamber (28) bounded by an upper surface (18), a lower surface (20), at least a first side surface (22) and at least a second side surface (24) opposing said first side surface (22);
a third side surface (23) and a fourth side surface (25) opposing said third side surface (23);
an air inlet opening (26) defined on said first side surface (22), said air inlet opening (26) adapted to channel air into said chamber (28);
an air outlet opening (30) defined on the second side surface (24), said air outlet opening (30) adapted to channel air out of said chamber (28); and
a flap (32) pivotally attached to a fifth side surface (21) that is adjacent to said at least said first side surface (22), said flap (32) adapted to be raised when airflow is channeled into said chamber (28) via said air inlet opening (26).

2. The fuel injected single cylinder naturally aspirated diesel engine (10) in accordance with Claim 1 further comprising an end stop (34) attached to said upper surface (18) of said unidirectional flow control valve (16), said end stop (34) adapted to stop a movement of said flap (32) in the upward direction.

3. The fuel injected single cylinder naturally aspirated diesel engine (10) in accordance with Claim 1 wherein said air inlet opening (26) is offset from said air outlet opening (30) along a length of said unidirectional flow control valve (16) to prevent a portion of air from flowing from the air outlet opening (30) to the air inlet opening (26).

4. The fuel injected single cylinder naturally aspirated diesel engine (10) in accordance with Claim 1 further comprising at least one spring member (36) secured to said flap (32) and coupled to said at least said first side surface (22), said flap (32) adapted to be raised against a resistive force of said at least one spring member (36) when airflow is channeled into said chamber (28) via said air inlet opening (26).

5. A unidirectional flow control valve (16) for a fuel injected single cylinder naturally aspirated diesel engine (10), said unidirectional flow control valve (16) comprising:
a chamber (28) bounded by an upper surface (18), a lower surface (20), at least a first side surface (22) and at least a second side surface (24) opposing said first side surface (22);
a third side surface (23) and a fourth side surface (25) opposing said third side surface (23);
an air inlet opening (26) defined on said first side surface (22), said air inlet opening (26) adapted to channel air into said chamber (28);
an air outlet opening (30) defined on the second side surface (24), said air outlet opening (30) adapted to channel air out of said chamber (28); and
a flap (32) pivotally attached to a fifth side surface (21) that is adjacent to said at least said first side surface (22), said flap (32) adapted to be raised when airflow is channeled into said chamber (28) via said air inlet opening (26).

6. The unidirectional flow control valve (16) in accordance with Claim 5 further comprising an end stop (34) attached to said upper surface (18), said end stop (34) adapted to stop a movement of said flap (32) in the upward direction.

7. The unidirectional flow control valve (16) in accordance with Claim 5 wherein said air inlet opening (26) is offset from said air outlet opening (30) to prevent a portion of air from flowing from the air outlet opening (30) back to the air inlet opening (26).

8. The unidirectional flow control valve (16) in accordance with Claim 5 further comprising at least one spring member (36) secured to said flap (32) and coupled to said at least said fifth side surface (21), said flap (32) adapted to be raised against a resistive force of said at least one spring member (36) when airflow is channeled into said chamber (28) via said air inlet opening (26).

, Description:Field of the invention
[0001] This invention relates to a unidirectional flow control valve, and more particularly to a unidirectional flow control valve for air flow in a single cylinder naturally aspirated diesel fuel injected internal combustion engine.

Background of the invention
[0002] U.S. Patent Application Number 4,445,336 describes an internal combustion engine. The internal combustion engine is equipped with a supercharger which includes an intake port, an intake passage communicated with the intake port and a compressor interposed in the intake passage and compressing the intake air flowing through the intake passage. A unidirectional valve such as a reed valve is disposed inside the intake passage in series with the compressor in order to prevent backflow of the supercharged air inside the intake passage and thus to prevent a drop in the engine output when a throttle valve inside the intake passage is abruptly closed.

Brief description of the accompanying drawings
[0003] Figure 1 illustrates a schematic diagram of an electronically controlled fuel injected single cylinder naturally aspirated diesel engine.
[0004] Figure 2 illustrates a front view of a unidirectional flow control valve for air in the single cylinder naturally aspirated diesel engine.
[0005] Figure 3 illustrates a front view of the unidirectional flow control valve for air in the single cylinder naturally aspirated diesel engine in another embodiment of the invention.
[0006] Figure 4 illustrates a flap of the unidirectional flow control valve illustrating a spring mechanism for securing the flap.

Detailed description of the invention
[0007] A fuel injected single cylinder naturally aspirated diesel engine layout 10 is described. The fuel injected single cylinder naturally aspirated diesel engine 10 comprises an engine 12 and an air suction valve adapted to be coupled to an inlet of the engine 12. A hot-film mass air-flow sensor 14 is positioned upstream from the engine 12. A unidirectional flow control valve 16 is positioned between the hot-film mass air-flow sensor 14 and the air suction valve. The unidirectional flow control valve 16 comprises a chamber 28 bounded by an upper surface 18, a lower surface 20, at least a first side surface 22 and at least a second side surface 24 opposing the first side surface 22, a third side surface 23, and a fourth side surface 25 opposing the third side surface 23. An air inlet opening 26 is defined on the first side surface 22, the air inlet opening 26 adapted to channel air into the chamber 28. An air outlet opening 30 is defined on the second side surface 24, the air outlet opening 30 adapted to channel air out of the chamber 28. A flap 32 is pivotally attached to a fifth side surface 21 that is adjacent to the at least first side surface 22, the flap 32 adapted to be raised when airflow is channeled into the chamber 28 via the air inlet opening 26.
[0008] In addition, a unidirectional flow control valve 16 for a fuel injected single cylinder naturally aspirated diesel engine 10 is described. The unidirectional flow control valve 16 comprises a chamber 28 bounded by an upper surface 18, a lower surface 20, at least a first side surface 22 and at least a second side surface 24 opposing the first side surface 22, a third side surface 23, and a fourth side surface 25 opposing the third side surface 23. An air inlet opening 26 is defined on the first side surface 22, the air inlet opening 26 adapted to channel air into the chamber 28. An air outlet opening 30 is defined on the second side surface 24, the air outlet opening 30 adapted to channel air out of the chamber 28. A flap 32 is pivotally attached to a fifth side surface 21 that is adjacent to the at least first side surface 22, the flap 32 adapted to be raised when airflow is channeled into the chamber 28 via the air inlet opening 26.
[0009] Figure 1 illustrates a schematic diagram of a fuel injection system 10. The fuel injection system 10 comprises an engine 12. A hot-film mass air-flow sensor 14 is positioned upstream from the engine 12 and measures a quantity of air that is supplied into the engine 12. A unidirectional flow control valve 16 is positioned between the hot-film mass air-flow sensor 14 and the engine 12 and permits a flow of air in one direction as will be explained in more detail below.
[0010] Figure 2 illustrates a front view of a unidirectional flow control valve 16 for the fuel injection system 10. The unidirectional flow control valve 16 comprises a chamber 28. The chamber 28 is bounded by an upper surface 18 and a lower surface 20. Moreover, the chamber 28 is also bounded by at least a first side surface 22 and at least a second side surface 24 that opposes the first side surface 22. The chamber 28 is bounded by a third side surface 23, and a fourth side surface 25 that opposes the third side surface 23. An air inlet opening 26 is defined on the first side surface 22. The air inlet opening 26 may be circular in shape. In an alternate exemplary embodiment, the air inlet opening 26 may be any other shaped opening. The air inlet opening 26 is adapted to channel air into the chamber 28 from a hot-film mass air-flow sensor 14.
[0011] A flap 32 is coupled to a fifth side surface 21 that is adjacent to the first side surface 22. More specifically, the flap 32 is pivotally coupled to the fifth side surface 21 and can be raised when air is channeled into the chamber 28 via the air inlet opening 26. The flap 32 comprises a thin deformable member that can be raised when airflow is channeled into the chamber 28 via the air inlet opening 26 from the hot-film mass air-flow sensor 14. An air outlet opening 30 is defined on the second side surface 24. The air outlet opening 30 permits a flow of air from the chamber 28 to the suction valve of the engine 12. When the suction valve of the engine is closed suddenly, the back pressure of air forces the air to return to the hot-film mass air-flow sensor 14. The unidirectional flow control valve 16 prevents a flow of air back to the hot-film mass air-flow sensor 14. An end stop 34 is attached to the upper surface 18 of the unidirectional flow control valve 16. The end stop 34 is adapted to stop a movement of the flap 32 in the upward direction. Therefore, the end stop 34 prevents the flap from sticking to the top surface 18 of the unidirectional flow control valve 16 when air is being channeled through the unidirectional flow control valve 16.
[0012] Figure 3 illustrates a front view of the unidirectional flow control valve 16 for the fuel injection system 10 in another embodiment of the invention. The unidirectional flow control valve 16 comprises a chamber 28. The chamber 28 is bounded by the upper surface 18 and the lower surface 20. Moreover, the chamber 28 is also bounded by at least the first side surface 22 and at least the second side surface 24 that opposes the first side surface 22. An air inlet opening 26 is defined on the first side surface 22. The air inlet opening 26 may be circular in shape. In an alternate exemplary embodiment, the air inlet opening 26 may be any other shaped opening. The air inlet opening 26 is adapted to channel air into the chamber 28 from a hot-film mass air-flow sensor 14.
[0013] The flap 32 is coupled to the fifth side surface 21 that is adjacent to the first side surface 22. More specifically, the flap 32 is pivotally coupled to the fifth side surface 21 and can be raised when air is channeled into the chamber 28 via the air inlet opening 26. The flap 32 comprises a thin deformable member that can be raised when airflow is channeled into the chamber 28 via the air inlet opening 26 from the hot-film mass air-flow sensor 14. An air outlet opening 30 is defined on the second side surface 24. The air outlet opening 30 is offset from the air inlet opening 26 such that the air inlet opening 26 is not coaxial with reference to the air outlet opening 30. The air outlet opening 30 permits a flow of air from the chamber 28 to the suction valve of the engine 12. When the suction valve of the engine is closed suddenly, the back pressure of air forces the air to return to the hot-film mass air-flow sensor 14. The unidirectional flow control valve 16 prevents the flow of air back to the hot-film mass air-flow sensor 14. The offset of the air outlet opening 30 with reference to the air inlet opening 26 does not allow for air to flow linearly from the air outlet opening 30 to the air inlet opening 26 without encountering the flap 32. Therefore, the flap 32 obstructs the flow of air from the air outlet opening 30 to the air inlet opening 26. The end stop 34 is attached to the upper surface 18 of the unidirectional flow control valve 16. The end stop 34 is adapted to stop a movement of the flap 32 in the upward direction. Therefore, the end stop 34 prevents the flap 32 from sticking to the top surface 18 of the unidirectional flow control valve 16 when air is being channeled through the unidirectional flow control valve 16.
[0014] Figure 4 illustrates the flap 32 of the unidirectional flow control valve 16 illustrating a spring mechanism 36 for securing the flap 32. The flap 32 comprises at least one spring mechanism 36. The at least one spring mechanism 36 is secured to the flap 32 and coupled to the first side surface 22 of the unidirectional flow control valve 16. The flap 32 may be raised against a resistive force of the at least one spring mechanism 36 when air flows through the air inlet opening 26 of the unidirectional flow control valve 16. After the airflow is complete, the flap 32 is restored to its original position due to the restoring force of the spring member 36 on the flap 32.
[0015] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to leverage and dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.