Engine and power generation systems

Abstract

To increase a flow rate of intake air.SOLUTION: An engine 100 comprises: a combustion chamber 103; an intake port 104 communicated with the combustion chamber 103; an opening 104a of the intake port 104 exposed to the combustion chamber 103; a first member 108a arranged on a side of the combustion chamber 103 opposite to an edge section (valve seat 106) of the opening 104a; an intake valve 108 which has a second member 108b installed so as to be rotatable with respect to the first member 108a; and a fin 108f installed on an outer periphery section of the second member 108b.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to engines and power generation systems. [Background technology]

[0002] There are engines that are equipped with an intake valve that opens and closes an intake port that communicates with a combustion chamber (see, for example, Patent Document 1). In such engines, the intake valve opens during the intake stroke, and intake air is drawn into the combustion chamber through the intake port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 049878 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to increase the flow rate of intake air during the intake stroke of the engine, as this increases the degree of freedom in setting the engine's operating specifications.

[0005] An object of the present disclosure is to provide an engine and power generation system that can increase the intake air flow rate. [Means for solving the problem]

[0006] In order to solve the above problems, the engine of the present disclosure includes an intake valve including a combustion chamber, an intake port communicating with the combustion chamber, an opening of the intake port facing the combustion chamber, a first member facing the edge of the opening from the combustion chamber side, and a second member rotatably provided relative to the first member, and fins provided on the outer periphery of the second member. The first member corresponds to a portion of the intake valve on the combustion chamber side relative to the intake port, and the second member is connected to the first member on the intake port side relative to the combustion chamber and corresponds to a portion of the intake valve other than the first member. .

[0007] There may be a motor connected to the second member.

[0008] A control device may be provided to rotate the motor at least during the intake stroke.

[0009] The control device may rotate the motor not only during the intake stroke but also during strokes other than the intake stroke.

[0010] In order to solve the above problem, a power generation system according to the present disclosure includes the above engine and a generator connected to the engine. [Effects of the Invention]

[0011] According to the present disclosure, the intake flow rate can be increased. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a power generation system according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of an engine according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is a schematic diagram of an intake valve according to an embodiment of the present disclosure viewed from above. [Figure 4] FIG. 4 is a diagram showing the intake stroke of the engine according to the embodiment of the present disclosure. [Figure 5] FIG. 5 is a diagram showing the state of the exhaust stroke of the engine according to the embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for ease of understanding and, unless otherwise specified, do not limit the present disclosure. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present disclosure are not shown.

[0014] FIG. 1 is a schematic diagram showing the configuration of a power generation system 1. As shown in FIG. 1, the power generation system 1 includes an engine 100 and a generator 200. The engine 100 generates power by burning fuel such as diesel or gasoline. The generator 200 is connected to an output shaft of the engine 100. The generator 200 generates power using the power transmitted from the engine 100.

[0015] FIG. 2 is a schematic diagram showing the configuration of engine 100. As shown in FIG. 2, engine 100 includes a cylinder block 101 and a cylinder head 102. A piston (not shown) is slidably housed in cylinder block 101. Cylinder head 102 covers an opening of cylinder block 101. A combustion chamber 103 is defined by cylinder block 101, cylinder head 102, and piston. In the following description, the side of cylinder head 102 relative to combustion chamber 103 is referred to as the upper side, and the side of combustion chamber 103 relative to cylinder head 102 is referred to as the lower side.

[0016] An intake port 104 and an exhaust port 105 are formed in the cylinder head 102. The intake port 104 and the exhaust port 105 communicate with the combustion chamber 103. The intake port 104 and the exhaust port 105 open to the underside of the cylinder head 102. A valve seat 106 is provided on the edge of an opening 104a of the intake port 104 that faces the combustion chamber 103. The valve seat 106 has an annular shape. The valve seat 106 corresponds to the edge of the opening 104a of the intake port 104. A valve seat 107 is provided on the edge of an opening 105a of the exhaust port 105 that faces the combustion chamber 103. The valve seat 107 has an annular shape. The valve seat 107 corresponds to the edge of the opening 105a of the exhaust port 105.

[0017] An intake valve 108 and an exhaust valve 109 are provided in the cylinder head 102. The intake valve 108 moves up and down to open and close an opening 104a of the intake port 104. The exhaust valve 109 moves up and down to open and close an opening 105a of the exhaust port 105. FIG. 2 shows the intake valve 108 and the exhaust valve 109 in a closed state. A fuel injection nozzle 110 is provided in the intake port 104. The fuel injection nozzle 110 injects fuel into the intake port 104.

[0018] Engine 100 is, for example, a four-stroke engine. During the intake stroke, intake valve 108 opens and exhaust valve 109 closes. As the piston moves toward bottom dead center, intake air and fuel are drawn into combustion chamber 103 through intake port 104. During the compression stroke, intake valve 108 and exhaust valve 109 close. As the piston moves toward top dead center, the air-fuel mixture in combustion chamber 103 is compressed. During the combustion stroke, the air-fuel mixture burns, pushing the piston toward bottom dead center. During the exhaust stroke, intake valve 108 closes and exhaust valve 109 opens. As the piston moves toward top dead center, burned exhaust gas is discharged from combustion chamber 103 through exhaust port 105.

[0019] The intake valve 108 is inserted into the opening 104a of the intake port 104. The intake valve 108 extends in a direction perpendicular to the opening 104a. That is, the intake valve 108 extends in the vertical direction. The outer diameter of the intake valve 108 is constant at the upper side and increases downward toward the combustion chamber 103. The intake valve 108 has a first member 108a and a second member 108b. The first member 108a is located at the lower end of the intake valve 108. The first member 108a corresponds to the lower part of the portion of the intake valve 108 whose outer diameter increases toward the combustion chamber 103. The second member 108b is connected to the upper part of the first member 108a. The second member 108b corresponds to the portion of the intake valve 108 whose outer diameter is constant and the upper part of the portion of the intake valve 108 whose outer diameter increases toward the combustion chamber 103.

[0020] The first member 108a faces the valve seat 106 from the combustion chamber 103 side. That is, the first member 108a faces the edge of the opening 104a of the intake port 104 from the combustion chamber 103 side. When the intake valve 108 is closed, the first member 108a abuts against the valve seat 106, thereby closing the opening 104a of the intake port 104. When the intake valve 108 is open, the first member 108a moves away from the valve seat 106, thereby opening the opening 104a of the intake port 104.

[0021] The second member 108b is rotatable relative to the first member 108a. In the example of FIG. 2, a protrusion 108c protruding upward is provided at the center of the top surface of the first member 108a. A hole 108d recessed upward is provided at the center of the bottom surface of the second member 108b. The outer ring of a bearing 108e is fitted into the inner circumferential surface of the hole 108d of the second member 108b. The protrusion 108c of the first member 108a is fitted into the inner ring of the bearing 108e. In this manner, the second member 108b is connected to the first member 108a via the bearing 108e. This allows the first member 108a and the second member 108b to rotate relatively around the central axis of the intake valve 108. The first member 108a is attached to the second member 108b so as not to fall out downward.

[0022] Fins 108f are provided on the outer periphery of the second member 108b. The second member 108b is rotated around the central axis of the intake valve 108 by a motor 112, which will be described later. When the second member 108b is rotated, the fins 108f also rotate. FIG. 3 is a schematic diagram of the intake valve 108 as viewed from above. As shown in FIG. 3, multiple fins 108f are provided at intervals in the rotation direction RD of the intake valve 108. In the example shown in FIG. 3, there are six fins 108f. However, the number of fins 108f may be other than six. The fins 108f extend so as to intersect with the rotation direction RD. As shown in FIG. 2, the fins 108f extend in the vertical direction when viewed from a direction perpendicular to the central axis of the intake valve 108. As shown in FIG. 3, the fins 108f extend radially outward from the center of the intake valve 108 when viewed from above. 3, when viewed from above, the central portion of the fin 108f is curved in the rotation direction RD. However, the shape of the fin 108f is not limited to the examples in FIGS.

[0023] As shown in FIG. 2, the upper part of the second member 108b is inserted into a bushing 111 provided in the cylinder head 102. The bushing 111 is fitted into a through-hole that penetrates from the upper surface of the cylinder head 102 to the inner surface of the intake port 104. A motor 112 is connected to the upper part of the second member 108b. The motor 112 is disposed coaxially with the intake valve 108. The operation of the motor 112 is controlled by a control device 113. The control device 113 includes a central processing unit (CPU), a ROM that stores programs and the like, a RAM as a work area, and the like. The control device 113 can rotate or stop the motor 112. When the motor 112 rotates, rotational power is transmitted from the motor 112 to the second member 108b, causing the second member 108b to rotate. As a result, the fins 108f rotate together with the second member 108b.

[0024] The top of the motor 112 is covered by a cover member 114. The cover member 114 has a generally cylindrical shape. The cover member 114 is disposed coaxially with the intake valve 108. A hole 114a is formed in the underside of the cover member 114. The top of the motor 112 is fitted into the hole 114a of the cover member 114. A protruding portion 114b that protrudes radially outward is formed at the upper end of the cover member 114. A spring 115 is provided between the protruding portion 114b of the cover member 114 and the upper surface of the cylinder head 102. The spring 115 biases the cover member 114 upward. The intake valve 108, motor 112, and cover member 114 can move up and down as a unit. When the top of the cover member 114 is pressed down by a cam (not shown), the intake valve 108 moves downward.

[0025] The exhaust valve 109 is inserted into the opening 105a of the exhaust port 105. The exhaust valve 109 extends in a direction perpendicular to the opening 105a. That is, the exhaust valve 109 extends in the vertical direction. The outer diameter of the exhaust valve 109 is constant at the top and increases at the bottom as it approaches the combustion chamber 103. The lower part of the exhaust valve 109 faces the valve seat 107 from the combustion chamber 103 side. When the exhaust valve 109 is closed, the lower part of the exhaust valve 109 abuts against the valve seat 107, thereby closing the opening 105a of the exhaust port 105. When the exhaust valve 109 is open, the lower part of the exhaust valve 109 is separated from the valve seat 107, thereby opening the opening 105a of the exhaust port 105.

[0026] The upper part of the exhaust valve 109 is inserted into a bushing 116 provided in the cylinder head 102. The bushing 116 is fitted into a through-hole that penetrates from the upper surface of the cylinder head 102 to the inner surface of the exhaust port 105. The upper part of the exhaust valve 109 is covered by a cover member 117. The cover member 117 has a substantially cylindrical shape. The cover member 117 is arranged coaxially with the exhaust valve 109. A hole 117a is formed in the lower surface of the cover member 117. The upper part of the exhaust valve 109 is fitted into the hole 117a of the cover member 117. A protrusion 117b that protrudes radially outward is formed at the upper end of the cover member 117. A spring 118 is provided between the protrusion 117b of the cover member 117 and the upper surface of the cylinder head 102. The spring 118 urges the cover member 117 upward. The exhaust valve 109 and the cover member 117 can move up and down together. When the upper part of the cover member 117 is pressed down by a cam (not shown), the exhaust valve 109 moves downward.

[0027] As described above, in this embodiment, the fins 108f are provided on the outer periphery of the second member 108b of the intake valve 108. Therefore, the fins 108f can be rotated by rotating the second member 108b. Here, the control device 113, for example, continuously rotates the motor 112 while the engine 100 is operating. In this case, the motor 112 rotates and the fins 108f rotate together with the second member 108b in all of the strokes, including the intake stroke, compression stroke, combustion stroke, and exhaust stroke. However, the control device 113 does not have to continuously rotate the motor 112 while the engine 100 is operating. For example, the control device 113 may rotate the motor 112 only during a portion of one cycle consisting of the intake stroke, compression stroke, combustion stroke, and exhaust stroke.

[0028] FIG. 4 is a diagram showing the intake stroke of engine 100. As shown in FIG. 4, during the intake stroke, intake valve 108 opens and exhaust valve 109 closes. FIG. 4 shows the motor 112 rotating and the fins 108f rotating together with the second member 108b during the intake stroke. During the intake stroke, intake air taken into combustion chamber 103 from intake port 104 flows radially outward from intake valve 108 through the gap between intake valve 108 and valve seat 106, as indicated by arrow A1.

[0029] When the fins 108f rotate during the intake stroke, momentum can be imparted to the intake air drawn into the combustion chamber 103 from the intake port 104 in a radially outward direction of the intake valve 108. This increases the flow rate of the intake air. Furthermore, because momentum is imparted to the intake air in a radially outward direction of the intake valve 108, separation of the intake air is suppressed when the intake air passes through the gap between the intake valve 108 and the valve seat 106. Suppression of separation of the intake air also promotes an increase in the flow rate of the intake air. This improves the flexibility in setting the operating specifications of the engine 100. Furthermore, the flow rate of the intake air can be increased without changing the dimensions of each component of the engine 100 or the lift amount of the intake valve 108. Furthermore, because fuel is injected into the intake port 104, the increased flow rate of the intake air is promoted, thereby promoting mixing of the intake air and the fuel.

[0030] In this embodiment, the second member 108b of the intake valve 108 is rotatable relative to the first member 108a that faces the edge of the opening 104a of the intake port 104 from the combustion chamber 103 side. Therefore, when the intake valve 108 is closed, if the second member 108b is rotating, the first member 108a that abuts against the valve seat 106 is prevented from rotating. This prevents the valve seat 106 and the first member 108a from rubbing against each other. This prevents wear and damage to the valve seat 106 and the intake valve 108.

[0031] Incidentally, immediately after the start and end of the intake stroke, the gap between the intake valve 108 and the valve seat 106 is small, so the intake air flow rate is likely to be particularly low. In this embodiment, the fins 108f can be rotated when the intake valve 108 is closed while suppressing wear and damage to the valve seat 106 and the intake valve 108. Therefore, for example, by pre-rotating the fins 108f before the start of the intake stroke, a lack of intake air flow rate immediately after the start of the intake stroke can be suppressed. Furthermore, for example, by continuing to rotate the fins 108f until the end of the intake stroke, a lack of intake air flow rate immediately before the end of the intake stroke can be suppressed. Therefore, the intake air flow rate can be effectively increased. Furthermore, since fuel is injected into the intake port 104, the intake air flow rate is effectively increased, which effectively promotes mixing of the intake air and the fuel.

[0032] Since the engine 100 is used as a power source for the generator 200 of the power generation system 1, it is larger than when used for purposes other than power generation. Therefore, increasing the intake air flow rate significantly improves the combustion efficiency of the engine 100. Therefore, the present disclosure is particularly effective in the power generation system 1.

[0033] As in the above example, it is preferable that the control device 113 rotates the motor 112 at least during the intake stroke. This appropriately rotates the fins 108f during the intake stroke. Therefore, it is appropriately realized to increase the flow rate of intake air.

[0034] However, the engine 100 does not necessarily have to include the motor 112. For example, the engine 100 may include a rotation mechanism other than the motor 112 as a rotation mechanism for rotating the second member 108b. In this case, the rotation mechanism other than the motor 112 may rotate the second member 108b to rotate the fins 108f, at least during the intake stroke. For example, if a female thread is formed on the inner circumferential surface of the bushing 111 and a male thread is formed on the outer circumferential surface of the second member 108b, and the male thread is threadedly engaged with the female thread, the male thread and the female thread correspond to the rotation mechanism. In this case, when the intake valve 108 moves up and down, the second member 108b rotates, and the fins 108f rotate. Therefore, the fins 108f can be rotated during the intake stroke. However, using the motor 112 as the rotation mechanism for rotating the second member 108b makes it easier to control the timing of the rotation of the fins 108f. Furthermore, the complexity of parts such as the bush 111 and the intake valve 108 can be reduced.

[0035] FIG. 5 illustrates the engine 100 during the exhaust stroke. As shown in FIG. 5, during the exhaust stroke, the intake valve 108 is closed and the exhaust valve 109 is open. FIG. 5 also illustrates the motor 112 rotating and the fin 108f rotating together with the second member 108b during the exhaust stroke. During strokes other than the intake stroke, such as the exhaust stroke, the intake valve 108 is closed. When the intake valve 108 is closed, some of the fuel injected from the fuel injection nozzle 110 may remain in the intake port 104. In such a case, when the fin 108f rotates, a flow directed upstream within the intake port 104 can be formed, as indicated by arrow A2. This allows the fuel-containing air in the intake port 104 to be pushed upstream. This prevents the fuel concentration from becoming locally high near the intake valve 108 within the intake port 104.

[0036] Here, while engine 100 is operating, a situation may arise in which both intake valve 108 and exhaust valve 109 are open. For example, when switching from the exhaust stroke to the intake stroke, both intake valve 108 and exhaust valve 109 may be open. When both intake valve 108 and exhaust valve 109 are open, a blow-by phenomenon may occur in which fuel remaining in intake port 104 is discharged through exhaust port 105. Therefore, during strokes other than the intake stroke, fin 108f is rotated to push fuel-containing air in intake port 104 upstream, thereby preventing a local increase in fuel concentration near intake valve 108, thereby preventing fuel from being discharged through exhaust port 105.

[0037] In this embodiment, when the intake valve 108 is closed, the fins 108f can be rotated while suppressing wear and damage to the valve seat 106 and the intake valve 108. Therefore, in strokes other than the intake stroke, such as the exhaust stroke, in which the intake valve 108 is closed, the fins 108f can be rotated while suppressing wear and damage to the valve seat 106 and the intake valve 108. Therefore, the air containing fuel in the intake port 104 can be pushed upstream while suppressing wear and damage to the valve seat 106 and the intake valve 108.

[0038] As in the above example, it is preferable that the control device 113 rotates the motor 112 not only during the intake stroke but also during strokes other than the intake stroke, thereby appropriately suppressing the discharge of fuel through the exhaust port 105.

[0039] However, as described above, the engine 100 may include a rotation mechanism other than the motor 112 as a rotation mechanism for rotating the second member 108b. In this case, the rotation mechanism other than the motor 112 may rotate the second member 108b to rotate the fins 108f in a stroke other than the intake stroke.

[0040] Although the embodiments of the present disclosure have been described above with reference to the accompanying drawings, it goes without saying that the present disclosure is not limited to such embodiments. It is clear that a person skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that such modifications and alterations also fall within the technical scope of the present disclosure.

[0041] In the above, an example has been described in which the engine 100 is used as a power source for the generator 200. However, the power output from the engine 100 may be used for purposes other than power generation.

[0042] In the above example, the first member 108a corresponds to the lower part of the portion of the intake valve 108 whose outer diameter increases toward the combustion chamber 103, and the second member 108b corresponds to the portion of the intake valve 108 whose outer diameter is constant and the upper part of the portion of the intake valve 108 whose outer diameter increases toward the combustion chamber 103. However, the boundary between the portion of the intake valve 108 occupied by the first member 108a and the portion of the intake valve 108 occupied by the second member 108b is not limited to the above example. For example, part of the portion of the intake valve 108 whose outer diameter is constant may be included in the first member 108a.

[0043] In the above, an example has been described in which the fuel injection nozzle 110 is provided in the intake port 104. However, the fuel injection nozzle 110 may be provided so as to face the combustion chamber 103. In this case, fuel is injected directly from the fuel injection nozzle 110 into the combustion chamber 103. [Explanation of symbols]

[0044] 1. Power generation system 100 Engine 103 Combustion chamber 104 Intake port 104a aperture 106 Valve seat (edge) 108 Intake valve 108a First member 108b Second member 108f Fin 112 Motor 113 Control device 200 generator

Claims

1. A combustion chamber; an intake port communicating with the combustion chamber; an opening of the intake port facing the combustion chamber; an intake valve having a first member facing an edge of the opening from the combustion chamber side, and a second member rotatable relative to the first member; fins provided on the outer periphery of the second member; Equipped with the first member corresponds to a portion of the intake valve that is on the combustion chamber side with respect to the intake port, the second member is connected to the first member on the intake port side with respect to the combustion chamber, and corresponds to a portion of the intake valve other than the first member; engine.

2. a motor connected to the second member; 10. The engine of claim 1.

3. A control device is provided that rotates the motor at least during the intake stroke.

3. The engine of claim 2.

4. the control device rotates the motor not only during the intake stroke but also during strokes other than the intake stroke; 4. The engine of claim 3.

5. An engine according to any one of claims 1 to 4; a generator connected to the engine; Equipped with Power generation system.

Images