JP4980314B2 - Internal combustion engine and drive system - Google Patents

Description

  The present invention relates to an improvement of an internal combustion engine and a drive system suitable for an automobile engine or the like.

Two-cycle and four-cycle internal combustion engines are known as automobile engines. The two-cycle engine has one explosion per revolution of the crankshaft, and the four-cycle internal combustion engine has one explosion every two revolutions. On the other hand, a six-cycle engine in which a scavenging intake stroke and a scavenging exhaust stroke are added after the four-stroke stroke is also known, resulting in one explosion per three rotations of the crankshaft. Patent Document 1 below includes an air intake stroke and a pressurizing stroke for pressurizing air in the combustion chamber during the transition from the exhaust stroke of the four cycles to the intake stroke. A six-cycle engine is disclosed in which compressed air is supplied to other cylinders in the latter half of the intake stroke.
Japanese Patent Laid-Open No. 2-119635

  By the way, with the recent rise in fuel and global warming countermeasures, a hybrid engine that combines an internal combustion engine and an electric motor is attracting attention. In addition, electric vehicles, hydrogen vehicles, fuel cell vehicles, etc. have been proposed as low environmental impact methods, but there are many such as requiring a long time for charging and infrastructure for filling hydrogen. There are challenges.

  The present invention pays attention to the above points, and provides an internal combustion engine and a drive system suitable for a hybrid system, which can improve fuel consumption and reduce environmental load such as suppression of global warming. That is the purpose.

In order to achieve the above object, the present invention is an internal combustion engine that opens and closes a valve when a piston reciprocates in a cylinder, and is provided with a pressurizing chamber for temporarily retaining pressurized air. The cylinder is provided with an intake valve, a pressurization chamber delivery valve, a pressurization chamber suction valve, and an exhaust valve, and the pressurization chamber is interposed between the pressurization chamber and the pressurization chamber suction valve. A throttle mechanism is provided for adjusting the amount of air sucked from the pipe , the throttle mechanism having a suction side connected to the pressurization chamber side and an exhaust side connected to the pressurization chamber suction valve side. The amount of air sucked from the pressurized chamber side and exhausted to the pressurized chamber suction valve side by opening and closing the pipeline in response to the operation of the road and the accelerator of the vehicle And a throttle valve that adjusts, when the piston is lowered by opening the intake valve, the intake stroke for sucking the air containing no fuel in the cylinder, when the piston is raised by the intake stroke pressurized air sucked into the cylinder, open the pressurizing chamber delivery valve, pressurized chambers delivery stroke to be transmitted to the pressure chamber, when the piston descends, pressurized by the pressurization chamber delivery stroke the air staying in the pressure chamber, open the pressure chamber inlet valve is closed the intake valve, with to return to suck into the cylinder that sent the air inhaling fuel into the cylinder at the same time pressure chamber suction stroke, when the piston rises, said sucked into the cylinder by the pressure chamber the suction stroke air The compression stroke for compressing the mixed gas charge, to burn and explosion of the gas mixture compressed by the compression stroke, combustion stroke to lower the piston, when the piston is raised, the residual gas after combustion by the combustion stroke, The exhaust valve is opened to repeatedly perform an exhaust stroke for exhausting from the cylinder.

According to one of the main forms, the diameters of the intake valve and the pressurization chamber delivery valve are set to be larger than the diameters of the exhaust valve and the pressurization chamber intake valve. One of the other forms is characterized in that the shape of the cam is defined so that the operations of the strokes do not overlap when the valves are opened and closed by the cam. According to another embodiment, in conjunction with the previous SL multi-cylinder structure in which a plurality of cylinders, characterized by sharing the pressure chamber between a plurality of cylinders. The drive system according to the present invention is characterized in that any one of the internal combustion engine and the electric motor is used in combination to form a hybrid system. The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

  According to the present invention, two self-pressurization cycles are applied to a four-cycle internal combustion engine, the air introduced into the cylinder is pressurized and delivered to the pressurization chamber, and then the air in the pressurization chamber is sent to the cylinder. Since the intake, compression, combustion, and exhaust are performed, the fuel consumption and the environmental load can be improved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail based on examples.

FIG. 1 shows the main part of this embodiment. As shown in FIG. 4, four valves 20, 30, 40, and 50 are provided for the cylinder 10. A pressurizing chamber 60 is provided between the valve 40 and the valve 50. Each valve and operation are as follows.
(1) Intake valve 20: This valve opens when air (atmosphere) is taken into the cylinder 10.
(2) Exhaust valve 30: This valve is opened when the gas after combustion is exhausted from the cylinder 10.
(3) Pressurized chamber delivery valve 40: A valve for delivering pressurized air in the cylinder 10 to the pressurized chamber 60.
(4) Pressurized chamber suction valve 50: A valve for sucking the pressurized air staying in the pressurized chamber 60 and returning it to the cylinder 10.

  FIG. 2A shows the size of the above-described valve. The intake valve 20 has a larger diameter or cross-sectional area than the exhaust valve 30 and can perform intake efficiently. Further, the pressurized chamber delivery valve 40 has a larger diameter or cross-sectional area than the pressurized chamber suction valve 50, and can efficiently deliver air to the pressurized chamber 60.

  Air is supplied from the intake port 22 to the intake valve 20 described above. The exhaust valve 30 is connected to an exhaust port 32 that exhausts residual gas after combustion. On the other hand, the pressurized chamber delivery valve 40 is connected to the air inlet of the pressurized chamber 60 via the pressurized delivery port 42. The air outlet of the pressurization chamber 60 is connected to the pressurization chamber suction valve 50 through the throttle mechanism 70 and the pressurization suction port 52 in this order. That is, the pressurized air delivered from the pressurized chamber delivery valve 40 and introduced into the pressurized chamber 60 is drawn into the cylinder 10 from the pressurized chamber suction valve 50 after the flow rate is adjusted by the throttle mechanism 70. It is like that.

  The size of the port is also set so as to correspond to the size of the valve described above. That is, the intake port 22 has a larger diameter or cross-sectional area than the exhaust port 32, and the pressurized delivery port 42 has a larger diameter or cross-sectional area than the pressurized intake port 52.

  FIG. 2B shows an example of the throttle mechanism 70 described above. As shown in the figure, a throttle valve 74 is provided at the center of the pipeline 72, and the pipeline can be opened and closed by rotating in the direction of arrow F74 with respect to the central axis. The throttle valve 74 responds to the operation of an automobile accelerator (not shown) as is well known, and the position shown by the solid line in the figure is a so-called idling state, and the position shown by the dotted line is a full throttle state where the accelerator is stepped on. It is. A bypass 76 is provided on the side surface of the pipeline 72, and a small amount of gas flow is secured through the bypass 76 even in an idling state. The bypass 76 is provided with an idle adjustment screw 78 for adjusting the gas flow rate in the idle state.

  Returning to FIG. 1, cams 120, 130, 140, and 150 (only 120 and 150 are shown) are provided at the ends of the above-described valves 20, 30, 40, and 50 through rocker arms 20A, 30A, 40A, and 50A, respectively. Are in contact with each other, and the opening / closing operation described later is performed by the rotation of the cams. Various types of these valve drive mechanisms are known, and any of them may be applied. A fuel ignition plug 12 is provided at the center of the cylinder surrounded by the valve.

  Further, a fuel port 71 is connected to the pressurized suction port 52 on the pressurized chamber suction valve 50 side so that fuel gas is supplied. This fuel gas is mixed with the air sent out from the throttle mechanism 70 and supplied into the cylinder 10. The amount of fuel gas is electronically controlled according to the movement of the accelerator, and the opening and closing of the throttle valve 74 of the throttle mechanism 70 also corresponds to the movement of the accelerator. Accordingly, the amount of compressed air and the amount of fuel are controlled in accordance with the movement of the accelerator.

  As described above, the fuel may be introduced into the cylinder 10 from the fuel port 71, or may be directly injected into the cylinder 10 by an injection nozzle. In the case of diesel, a fuel injection nozzle is provided instead of the plug 12.

3 and 4 show the state of the main part in each process of 6 cycles in the present embodiment. 3 and 4 show four valves 20, 30, 40, and 50 in parallel in order to facilitate understanding of the present invention. The point that the piston 14 in the cylinder 10 is joined to the crankshaft 18 via the connecting rod 16 is the same as in the known technique. Hereinafter, operations in each process will be described in order.
(1) Intake stroke: As shown in FIG. 3A, the piston 14 in the cylinder 10 descends as indicated by the arrow F3A, the intake valve 20 opens, and air is taken into the cylinder 10.
(2) Pressurized chamber delivery process: As shown in FIG. 3 (B), the piston 14 in the cylinder 10 rises as shown by an arrow F3B, and the pressurized chamber delivery valve 40 opens to provide pressurized air. Is delivered to the pressurized chamber 60.
(3) Pressurization chamber suction stroke: As shown in FIG. 3C, the piston 14 in the cylinder 10 descends as shown by an arrow F3C, and the pressurization chamber suction valve 50 opens. Thereby, the pressurized air staying in the pressurizing chamber 60 is mixed with the fuel gas and sucked into the cylinder 10 again. The amount of pressurized air at this time is adjusted by the throttle mechanism 70 as described above.
(4) Compression stroke: As shown in FIG. 4 (D), with all of the valves 20, 30, 40, 50 closed, the piston 14 rises as indicated by the arrow F3D, and the mixed gas flows in the cylinder 10. Compressed.
(5) Combustion stroke: As shown in FIG. 4E, the plug 12 is ignited, and the mixed gas compressed in the cylinder 10 is burned and exploded. The piston 14 descends as indicated by an arrow F3E.
(6) Exhaust stroke: As shown in FIG. 4 (F), with the exhaust valve 30 opened, the piston 14 rises as indicated by the arrow F3F, and the residual gas in the cylinder 10 is exhausted.

Next, when attention is paid to the movement of the cams 120, 130, 140, 150, it is as follows. Each cam makes one rotation in the 6 cycles shown in FIGS.
(1) Cam 120: A cam for opening and closing the intake valve 20, and pushes and opens the intake valve 20 only in the intake stroke of FIG.
(2) cam 130: cam for opening and closing the exhaust valve 30 opens by pressing only the exhaust valve 30 in the exhaust stroke of Fig. 4 (C).
(3) Cam 140: A cam for opening and closing the pressurization chamber delivery valve 40, and pushes and opens the pressurization chamber delivery valve 40 only in the pressurization chamber delivery process of FIG.
(4) Cam 150: A cam for opening and closing the pressurization chamber suction valve 50. The cam 150 pushes and opens the pressurization chamber suction valve 50 only in the pressurization chamber suction process of FIG.

  FIG. 5A shows the entire process described above. In the figure, the bottom dead center indicates the position where the piston 14 is lowered most, and the top dead center indicates the position where the piston 14 is raised most. According to the present embodiment, the six steps in FIG. 5A are sequentially repeated in the clockwise direction.

  FIG. 5B shows an example of the cam 120 described above. Since the cams 130, 140, and 150 have the same shape, the cam 120 will be described below as a representative. FIG. 2B is a view seen from the direction of the camshaft 100, and FIG. 2C is a view seen from the side of the camshaft 100. FIG. As shown in these drawings, the cam crest 122 is formed in a range of 60 degrees, thereby pushing the intake valve 20 once every six cycles. Specifically, it rises so as to draw an arc with a radius of 2 millimeters (R2), with the base point at 5 degrees inside the range of 60 degrees, and the top portion draws an arc with a radius of 4 millimeters (R4). The fall of the cam mountain 122 is symmetrical with the rise. In the case of a general 4-cycle engine, an example is shown by a dotted line in FIG.

  The correspondence relationship between such a cam 120 and each cycle described above is shown in an overlapping manner in FIG. That is, the time when the cam crest 122 of the cam 120 pushes the intake valve 20 is the air intake stroke. The same applies to the other cams 130, 140, 150. As described above, the cams 120, 130, 140, and 150 all correspond to 6 cycles in one rotation. On the other hand, as shown in FIGS. 3 and 4, the crankshaft 18 makes one rotation in two cycles, and therefore makes three rotations in six cycles. Thus, according to the present embodiment, the rotational speed of the camshaft 100 is 1/3 of the rotational speed of the crankshaft 18.

  Further, since the rise of the cam crest of the cams 120, 130, 140, and 150 is delayed and the fall is accelerated, as shown in FIG. 5 (A), several degrees before and after the top dead center and the bottom dead center. Between (in the illustrated example, 2 degrees), the valve opening and closing operations of each cycle do not overlap and overlap does not occur. For example, in the example of the cam 120 shown in FIG. 5B, as described above, the cam crest 122 rises from a position shifted from 60 degrees by 5 degrees, thereby preventing the overlap from occurring. Yes. Note that the overlap avoidance angle shown in FIG. 5 (A) and the rising base angle of the cam crest 122 shown in FIG. 5 (B) are not necessarily the same due to the difference between the static characteristics and the dynamic characteristics. .

  FIG. 6 shows the relationship between the angles of the cams 120, 130, 140, and 150 and the cam lift. The graph G6 is the case of the present embodiment, as described above, rising from 5 degrees, peaking at 30 degrees, and zero lift at 55 degrees. Graph G4 shows an example of the cam lift in the case of 4 cycles, rising from 0 degrees, peaking at 45 degrees, and lift amount being zero at 90 degrees. When the crankshaft rotation speed is the same, the rotation of the camshaft in 6 cycles is slower than in the case of 4 cycles. For this reason, the time for which the valves 20, 30, 40 and 50 are opened in the case of 6 cycles in this embodiment approaches that in the case of 4 cycles (see arrow in FIG. 6).

  FIG. 7 shows an example of the relationship between the engine output, the pressurizing pressure in the pressurizing chamber 60, and the throttle valve angle with respect to the crankshaft rotational speed (engine rotational speed). Focusing on the throttle valve angle graph GS, the angle at the idling point is zero, and the angle increases as the rated output point is reached. Focusing on the engine output graph GE, there is an output of ΔW at the idling point, and the engine output increases as the throttle valve angle increases. That is, as the throttle valve 74 is rotated and opened, the amount of mixed gas sucked into the cylinder 10 increases, and the engine output also increases. On the other hand, the pressurizing chamber pressure is the highest at the idling point as shown in the graph GC, and decreases as the throttle valve angle increases.

  Next, paying attention to the idling point where the throttle valve 74 is closed, the crankshaft rotates at a rotational speed of ΔR. At this time, the engine output is ΔW. On the other hand, paying attention to the rated output point, the throttle valve 74 is fully opened, so that the engine output becomes maximum. However, since the pressurized chamber delivery valve 40 and the pressurized chamber suction valve 50 are different in size, the pressure ΔP is slightly generated.

  FIG. 8 shows an example of a cycle relationship between cylinders in the case of multiple cylinders. In the figure, the horizontal axis represents time, and the vertical axis represents the amount of gas drawn or exhausted (the degree of valve opening). First, in the case of one cylinder, as shown in FIG. 5A, six cycles of intake, pressurized chamber delivery, pressurized chamber suction, compression, combustion, and exhaust are repeated. In the case of two cylinders, one cylinder performs the operation (A), and the other cylinder performs, for example, a three-cycle delayed operation shown in FIG. In the case of three cylinders, the first cylinder performs the operation (A) described above, the second cylinder performs an operation delayed by two cycles as shown in FIG. The operation with a delay of 4 cycles shown in FIG.

As described above, according to this embodiment, there are the following effects.
(1) A two-cycle self-pressurization cycle is added to a four-cycle engine, and after the intake stroke, air is sent to the pressurization chamber 60 and pressurized air is sucked from the pressurization chamber 60. Combustion is performed at the gas pressure. For this reason, although it is 6 cycles, the torque thru | or horsepower close | similar to 4 cycles are obtained. In addition, compared with four cycles, fuel consumption and exhaust gas can be reduced.
(2) Since the engine rotation time per cycle is 1.5 times longer than that of the 4-cycle engine, the efficiency reduction in each cycle is suppressed to 30%. Further, since the rotation of the camshaft is also 1.5 times slower than the 4-cycle internal combustion engine, the period loss ratio is also reduced. In addition, since the camshaft drive resistance is small, mechanical noise is reduced and it is effective for low noise, and the same number of cylinders and combustion order as the current four-cycle engine can be used, thus reducing the production cost. Can do. Furthermore, the wear rate of parts such as cams and shafts can be suppressed.
(3) When the engine speed is the same, the number of combustions is reduced as compared with the case of four cycles, so the amount of exhaust gas is reduced. In addition, by combining with the electric motor drive and adopting a hybrid system, it is possible to improve fuel consumption, further reduce exhaust gas, and reduce environmental burdens such as suppression of global warming.
(4) The intake valve 20 and the intake port 22, the pressurized chamber delivery valve 40 and the pressurized delivery port 42 are made larger than the exhaust valve 30 and the exhaust port 32, the pressurized chamber intake valve 50 and the pressurized intake port 52. Therefore, the intake of air and the delivery to the pressurized chamber 60 are sufficiently performed. For this reason, even if there is residual gas after combustion, the intake air will be sufficiently mixed, and this will be pressurized and burned again, improving combustion efficiency and suppressing the generation of nitrogen oxides and carbon dioxide can do.
(5) Since there is no overlap in the valve opening / closing operation by the cam, unburned gas can be sent to the pressurized chamber 60 and combustion can be performed again.

In addition, this invention is not limited to the Example mentioned above, A various change can be added in the range which does not deviate from the summary of this invention. For example, the following are also included.
(1) In the above embodiment, the case of one cylinder (one cylinder) has been mainly described. Of course, a known multi-cylinder configuration does not prevent smooth rotation of the crankshaft.
(2) A pressurization chamber may be provided for each cylinder. However, since air is fed into and sucked into the pressurization chamber in two cycles, one pressurization chamber is provided for three cylinders and sequentially By using it, the device configuration can be simplified.
(3) It does not prevent application of known techniques such as a valve opening / closing mechanism and a piston mechanism.
(4) The present invention is mainly suitable for a gasoline engine, but can be applied to various fuels such as diesel, LPG, and ethanol. Moreover, you may apply not only to a motor vehicle but to various uses, such as a ship and a generator.

  According to the present invention, although the output is somewhat reduced, the fuel consumption is reduced and the environmental load is also suppressed, which is suitable for a hybrid internal combustion engine.

It is a perspective view which shows the principal part of the Example of this invention. It is a figure which expands and shows a part of said FIG. It is a figure which shows the mode of operation | movement in the said Example. It is a figure which shows the mode of operation | movement in the said Example. It is a figure which shows the whole operation | movement of the said Example, and an example of a cam. It is a graph which shows the relationship between the angle of a cam and the lift amount in the said Example. It is a graph which shows the relationship between the crankshaft rotation speed, engine output, etc. in the said Example. It is a figure which shows an example of the relationship of the cycle between cylinders in the case of applying the said Example to many cylinders.

Explanation of symbols

10: cylinder 12: plug 14: piston 16: connecting rod 18: crankshaft 20: intake valve 20A, 30A, 40A, 50A: rocker arm 22: intake port 30: exhaust valve 32: exhaust port 40: pressurized chamber delivery valve 42 : Pressurization delivery port 50: Pressurization chamber suction valve 52: Pressurization suction port 60: Pressurization chamber 70: Throttle mechanism 71: Fuel port 72: Pipe line 74: Throttle valve 76: Bypass 78: Idle adjustment screw 100 : Camshaft 120, 130, 140, 150: Cam 122: Cam mountain

Claims (5)

An internal combustion engine that opens and closes a valve when a piston reciprocates in a cylinder,
A pressurized chamber is provided for temporarily retaining pressurized air;
The cylinder is provided with an intake valve, a pressurized chamber delivery valve, a pressurized chamber intake valve, and an exhaust valve,
Between the pressurization chamber and the pressurization chamber suction valve, a throttle mechanism for adjusting the amount of air sucked from the pressurization chamber is provided,
The throttle mechanism has an intake side connected to the pressurization chamber side, an exhaust side connected to the pressurization chamber intake valve side, and opens and closes the conduit in response to the operation of the vehicle accelerator. And a throttle valve that adjusts the amount of air sucked from the pressurized chamber side and exhausted to the pressurized chamber suction valve side,
When the piston descends, the intake valve is opened to intake air that does not contain fuel into the cylinder;
A pressurization chamber delivery stroke for pressurizing air sucked into the cylinder by the intake stroke and opening the pressurization chamber delivery valve to deliver the piston to the pressurization chamber when the piston moves up ;
When the piston descends, the air staying in the pressurization chamber by the pressurization chamber delivery process is opened in the cylinder that has sent out the air by opening the pressurization chamber suction valve with the intake valve closed. together to return to the suction, pressurization chamber intake stroke for sucking the fuel into the cylinder at the same time,
A compression stroke for compressing a mixed gas of air and fuel sucked into the cylinder by the pressurized chamber suction stroke when the piston moves up ;
Combustion stroke that burns and explodes the gas mixture compressed by this compression stroke and lowers the piston ,
An exhaust stroke in which, when the piston is raised , residual gas after combustion in the combustion stroke is exhausted from the cylinder by opening the exhaust valve;
An internal combustion engine characterized by repeating the above.   2. The internal combustion engine according to claim 1, wherein the intake valve and the pressurization chamber delivery valve are set to have a diameter larger than that of the exhaust valve and the pressurization chamber intake valve.   The shape of the cam is defined so that the operation of each stroke does not overlap when the valve is opened and closed by the cam in each stroke. Internal combustion engine.   The internal combustion engine according to any one of claims 1 to 3, wherein a plurality of cylinders are provided, and the pressurizing chamber is shared among the plurality of cylinders.   5. A hybrid drive system using the internal combustion engine according to claim 1 and an electric motor in combination.

Images