JP5050861B2 - Intake control device for internal combustion engine - Google Patents

Description

  The present invention relates to a technical field of an intake control device for an internal combustion engine capable of inertia supercharging such as impulse charge.

  As this type of device, Patent Document 1 discloses a configuration in which an intake control valve is provided in an intake passage downstream of a surge tank. According to this configuration, it is supposed that an inertial supercharging effect can be obtained by opening the intake control valve after the intake valve downstream of the intake port is opened.

  Patent Document 2 discloses a technique for avoiding knocking by controlling the opening / closing timing of the intake control valve to suppress the supercharging pressure in the first cycle of inertial supercharging. Further, for example, Patent Document 3 discloses a technique in which a peripheral portion of a surge tank is formed so as to be covered with an intake manifold that is one mode of an intake passage communicating with the inside of a cylinder.

JP-A-5-187238 JP 2005-171941 A JP 2003-41956 A

  By the way, in the intake system of the internal combustion engine in which the above-described inertia supercharging is performed, a large-capacity surge tank is required to reflect the negative pressure wave generated by the intake control valve and send it back to the intake control valve as a positive pressure wave. The At this time, if the intake passage is provided with a large-capacity surge tank, the mountability of the internal combustion engine on the vehicle may be deteriorated. In particular, according to the technique disclosed in Patent Document 3, since a large-capacity surge tank is formed so as to be covered with an intake manifold, restrictions are imposed on the shape of the surge tank. This causes a technical problem that the occupied volume further increases.

  On the other hand, it has been pointed out as a technical problem that noise is generated by pulsation of intake air generated in a surge tank when inertial supercharging is performed.

  The present invention has been made in view of the above-described problems, and improves the vehicle mountability of a large-capacity surge tank provided in an internal combustion engine that performs inertial supercharging, and on the other hand, pulsation of intake air accompanying inertial supercharging. An object of the present invention is to provide an intake control device for an internal combustion engine that can suitably suppress noise caused by the intention.

  In order to solve the above problems, an intake control device for an internal combustion engine according to the present invention is mounted on a vehicle, and is provided in an intake passage communicating with the inside of a cylinder, and generates intake air pulsation according to an open / close state. An intake control valve capable of adjusting the intake amount that is possible and the intake amount, and a phase inversion that is installed upstream of the intake control valve in the intake passage and inverts the phase of the pulsating wave corresponding to the generated pulsation The phase inversion means comprises: (i) a cross section in a direction crossing the intake passage, and an outer pipe having a cross sectional area in a direction crossing the intake passage larger than that in the intake passage. (Ii) an upstream end of the outer pipe is connected to the intake passage, and a downstream end of the inner pipe is the inner cross section of the intake passage. Connected to the outside of the tube, (iii) said inside And the downstream end is connected to the intake passage, and (iv) the intake air is connected to the upstream end of the outer pipe. The distance a between the end of the passage and the upstream end of the inner pipe is larger than the inner diameter d of the inner pipe and smaller than twice the inner diameter d of the inner pipe.

  The “internal combustion engine” according to the present invention has one or a plurality of cylinders, and various fuels such as gasoline, light oil, various alcohols, or a mixed fuel of various alcohols and gasoline, or the like in a combustion chamber in each of the cylinders. The force generated when an air-fuel mixture containing various fuels explodes or burns can be taken out as a driving force through a physical or mechanical transmission path such as a piston, a connecting rod and a crankshaft. It is a concept that encompasses various institutions. Further, the “intake device of the internal combustion engine” related to this type of internal combustion engine includes intake air (ie, intake air as air sucked from the outside world) as a part of the concept, and the intake air itself, Or, for example, when an exhaust gas recirculation device such as an EGR device is provided, for example, an EGR gas (that is, a part of exhaust gas) and a mixture of the intake air, etc. It can be used in various forms.

  The “intake passage” in the intake device of the internal combustion engine according to the present invention is an intake passage, and as a preferred form, for example, an air cleaner, an air flow meter, a throttle valve (ie, an intake throttle valve), and an intake port. For example, it takes the form of a single or a plurality of tubular members that can be connected or communicated with each other as appropriate. In particular, the intake device for an internal combustion engine according to the present invention may be a part of the intake passage excluding, for example, a turbocharger or other supercharger (of course, a part such as a turbine that should be provided in the exhaust system). And the downstream side (where “downstream” is a direction concept based on the direction of intake air flow, in this case, that is, the cylinder side), for example, an intercooler, etc. The intake air cooling means is provided. The intake air cooling means is physically and mechanically capable of cooling the intake air supplied via the supercharger (which may be independent of whether or not supercharging by the supercharger is practically significant). Means having a mechanical, electrical, magnetic or chemical aspect, at least somewhat more and relatively cooling the intake air, thereby increasing the intake air density and It can improve.

  On the other hand, the intake device for an internal combustion engine according to the present invention includes an intake control valve on the downstream side of the intake air cooling means in the intake passage. The intake control valve can generate at least pulsation of intake air and can adjust the intake air amount corresponding to the intake air amount according to an open / close state that can be controlled, for example, in a binary manner, stepwise or continuously. For example, it is means that can take the form of a valve mechanism or a valve mechanism or the like that appropriately includes a valve body or a drive device that drives the valve body in addition to the valve body. When the internal combustion engine is provided with a so-called intake throttle valve such as a throttle valve, the intake control valve is installed on the downstream side of the intake throttle valve as a preferred form.

  The installation mode of the intake control valve may take various forms depending on, for example, the physical configuration of the intake passage. That is, the intake passage may branch to each cylinder on the downstream side of the intake control valve (that is, an aspect similar to a so-called one-valve impulse charge system), and each intake cylinder is provided with an intake control valve. May include an intake branch pipe (including a similar one) (that is, an aspect similar to a so-called multi-valve impulse charge system). In any case, the intake control valve sends intake air to each cylinder as a pulsating wave (as a preferred form, the intake air can be basically taken into the cylinder as a pulsating wave regardless of the presence or absence of the intake control valve. However, as a preferred form, the pulsation generated by the intake control valve is a pulsation stronger than this type of pulsation (for example, apart from the generation of this type of pulsation, for example, a throttle valve, for example) When the intake air adjustment (intake throttle), which can be suitably performed by opening / closing the intake throttle valve, etc., can be practiced to such an extent that there is no practical problem, the operation of the intake throttle valve such as the throttle valve is performed according to the present invention. (Or, conversely, the intake throttle valve may replace its function as the intake control valve according to the present invention)), and as a preferred embodiment, its opening and closing Less Both may be installed in a position close to the intake valve of each cylinder to the extent that may cause pulsations in practice sufficient intake.

  As described above, an internal combustion engine including an intake control valve can perform inertial supercharging (also referred to as pulse supercharging or impulse charge) using intake air pulsation regardless of whether the intake control valve is single or plural. Thus, for example, control of the intake control valve opening / closing timing, valve opening period or opening (that is, the degree of valve opening, which uniquely defines the opening / closing state) (for example, the portion corresponding to the peak of the pulsation wave of intake air) For example, control to synchronize with the vicinity of the closing timing of the intake valve), for example, a larger amount of intake can be taken into the cylinder in the intake stroke than when natural intake is performed. In addition, the intake control valve can adjust the intake air amount regardless of what mode the open / close state can take, and whether or not it is practically easy, for example, the intake valve opening period It is also possible to reduce the pumping loss by the intake early closing control that substantially blocks the inflow of intake air in the middle of the process.

  Here, in the intake device of the internal combustion engine according to the present invention, when this kind of inertia supercharging using the intake control valve is realized, in addition to the opening / closing control of the intake control valve, a form such as a surge tank can be adopted, for example. The phase inversion action of the pulsating wave corresponding to the pulsation by the phase inversion means is used. Here, as expressed as “a pulsation wave corresponding to a pulsation”, the pulsation wave used for phase inversion according to the phase inversion means is, as a preferred form, an appropriate time lapse after opening the intake valve ( This may be caused by opening the intake control valve via a crank angle (which may be defined as an angle concept) (ie, the downstream side of the intake control valve is negative pressure and the upstream side of the intake control valve is above atmospheric pressure) Instead of the primary pulsating wave (positive pressure wave) generated by the reflected wave, the primary pulsating wave is reflected near the entrance of the combustion chamber of each cylinder, which can be regarded as an open end (that is, the primary pulsating wave). A pulsating wave is a negative pressure wave whose phase is reversed. The inertia supercharging described above is realized by a so-called secondary pulsating wave (that is, a positive pressure wave) obtained by inverting the phase of the reflected wave.

  Here, in particular, the phase inversion means in the intake device of the internal combustion engine according to the present invention is such that the cross section of the cross section in the direction intersecting the intake passage intersects the intake pipe and the outer pipe having a larger cross section than the cross section of the intake passage The cross-sectional area of the inner pipe is the same as the cross-sectional area of the intake passage, and the upstream end of the outer pipe is connected to the intake passage, and the downstream end is connected to the outside of the inner pipe. The upstream end of the inner pipe is an open end inside the outer pipe, and the downstream end is connected to the intake passage. In other words, the upstream end of the inner pipe that is an extension of the downstream intake passage is an open end, and an outer pipe is formed so as to cover the periphery of the inner pipe. The end has an opening, and is connected to the upstream intake passage through the opening, and the downstream end of the outer pipe is connected to the outer wall of the inner pipe to form a closed end. The capacity increasing part between the inner pipe and the outer pipe is made to function as a surge tank. In the surge tank configured as described above, the negative pressure wave from the intake control valve that has passed through the inner pipe connected to the downstream intake passage is reflected at the upstream end of the inner pipe that forms the open end. As described above, a secondary pulsation wave is generated, and inertial supercharging is realized.

  Typically, in order to realize the above-described inertia supercharging, there is a technical requirement for one end of the intake passage to be an open end, and accordingly, a large-capacity surge tank is required. However, since the optimal value is determined for the length and diameter of the intake passage according to the displacement of the internal combustion engine, the intake passage when the internal combustion engine is mounted on the vehicle, and the mounting location of the surge tank connected to the intake passage Technical restrictions may be imposed on the decision. On the other hand, by configuring the surge tank as described above, the air gap around the intake passage can be effectively utilized, and the position of the surge tank (typically determined by the position of the open end of the intake passage). The degree of freedom of the shape of the surge tank (typically depending on the shape of the outer tube that constitutes the surge tank) is increased, resulting in a dramatic increase in mountability to the vehicle. It is possible to squeeze.

  Further, in the inertial supercharging described above, the pulsation of the generated intake air is very large and the frequency thereof also tends to increase, and an intake passage (typically, the open end of the intake passage) that generates the pulsation of the intake air. In other words, at the upstream end of the surge tank inner pipe, noise may be generated due to the vibration of the wall surface constituting the passage. On the other hand, by configuring the surge tank as described above, the vicinity of the open end of the intake passage where the above-described intake air pulsation is generated is formed so as to be covered by the outer pipe. Leakage can be suitably suppressed.

  Further, according to this aspect, the upstream end of the inner pipe which is an open end in the surge tank, and the end of the upstream intake passage connected to the surge tank (that is, the connection to the outer pipe) It is possible to suitably set the distance a.

  Here, when the above-mentioned distance a is shorter than necessary, the pressure of the pulsating wave from the open end of the inner pipe due to inertia supercharging escapes to the intake passage on the upstream side of the surge tank. There is a possibility that the capacity increase portion of the tank (that is, the volume between the inner pipe and the outer pipe) is not effectively used, and the positive pressure wave generated by the reversal of the negative pressure wave at the open end is reduced.

  On the other hand, when the distance a is longer than necessary (for example, when it is sufficiently longer than the length of the outer tube), the configuration of the conventional surge tank that does not depend on the configuration of the present invention is approached. There is a possibility that the problem of providing a remarkable effect of improving the mountability of the surge tank to the vehicle and suitably suppressing intake noise in the inertial supercharger may not be solved.

  In view of the above technical problems, the distance a is determined based on the inner diameter d of the inner tube, so that the effect of inertia supercharging according to the surge tank of the present invention is preferably secured while being mounted on a vehicle. And the effect of suppressing intake noise can be improved.

  Furthermore, it is preferable that the open end of the inner tube has a funnel-like shape that preferably extends outward. By configuring in this way, when intake air from the upstream side of the intake passage flows into the inner pipe through the open end, the so-called air pressure loss that the intake air flows out to the outside of the open end at the open end is reduced. It can reduce suitably.

  Furthermore, it is preferable that a support means such as a stay is provided between the inner tube and the outer tube. By comprising in this way, destruction or damage of an inner pipe resulting from the vibration of the inner pipe accompanying generation | occurrence | production of the pulsation of inhalation can be suppressed suitably.

  As described above, according to the intake control device for an internal combustion engine according to the present invention, the surge tank has an inner pipe that forms an open end as an extension of the intake passage, and an outer pipe that is formed so as to cover the inner pipe. With this configuration, it is possible to dramatically improve the mountability of the internal combustion engine including the surge tank on a vehicle, and to appropriately suppress noise caused by inertia supercharging.

  Another aspect of the intake control device for an internal combustion engine according to the present invention includes at least a central axis in the vicinity of the end of the intake passage connected to the upstream side of the outer pipe, and at least in the vicinity of the upstream end of the inner pipe. The central axes are arranged on the same line.

  According to this aspect, the upstream end of the inner pipe, which is the open end of the surge tank, and the upstream intake passage connected to the surge tank have a central axis on the same line. It is configured to face each other. The inner pipe or the upstream intake passage may be bent due to technical demands associated with improved mounting of the vehicle, or for some other reason, but in this aspect, at least the inner pipe and the upstream The central axes in the vicinity of both ends of the intake passage on the side are arranged on the same line.

  With this configuration, it is possible to suitably prevent an intake pressure loss from increasing due to a decrease in the amount of inflow into the inner pipe due to bending of the intake air flowing in from the upstream intake passage at the open end. It is possible. As a result, a reduction in intake air flowing into the cylinder can be suppressed, and an increase in pump loss and a reduction in engine thermal efficiency can also be suppressed. In other words, by configuring in this way, the flow of intake air in the surge tank portion becomes smooth, and intake pressure loss is reduced, so that high speed performance and engine thermal efficiency can be improved.

  Alternatively, in this aspect of the intake control apparatus for an internal combustion engine of the present invention, the inner diameter in the vicinity of the end of the intake passage connected to the upstream side of the outer pipe has a tapered shape that becomes smaller toward the end.

  With this configuration, the vicinity of the end portion of the upstream intake passage facing the open end of the inner pipe has a tapered shape in which the inner diameter becomes smaller as it approaches the end portion. This makes it possible to create a flow toward the central axis of the intake passage at the open end of the surge tank inlet, and to facilitate the inflow of intake air to the open end of the smooth inner pipe. As a result, the intake pressure loss at the entrance of the surge tank is reduced, so that high speed performance and engine thermal efficiency can be improved.

  Further, with this configuration, when the pulsation wave generated in the intake control valve is reflected in the surge tank when the inertia supercharging is performed, it flows out to the intake passage on the upstream side of the surge tank ( That is, it is possible to suitably suppress backflow. As a result, the reflection efficiency of the positive pressure wave generated by reflecting the negative pressure wave can be improved, and the volume effect improvement rate in inertial supercharging can be further improved.

  Alternatively, in this aspect, the ratio (L / D) between the length L of the outer tube and the diameter D of a circle having the same area as the cross-sectional area of the cross-section in the direction intersecting the intake passage of the outer tube. 3 or more and 5 or less.

  The surge tank configured as described above has a length of the outer pipe (that is, the intake passage of the surge tank) as compared with the cross-sectional area in the direction intersecting with the intake passage (that is, the area of a circle having a radius of D / 2). The length in the direction) is sufficiently long.

  When the above ratio L / D is larger than necessary, the inner diameter of the outer pipe (and consequently the inner diameter of the surge tank) becomes smaller, and the effect of attenuating pressure pulsation as a surge tank is reduced, resulting in inertial supercharging. There is a possibility that the volume effect improvement rate in the case will be reduced. On the other hand, when the ratio L / D is smaller than necessary, there is a technical requirement that the inner diameter of the outer tube must be very large in order to obtain the capacity necessary to exhibit the effect as a surge tank. Imposed, and there is a risk of significantly worsening the mountability to the vehicle.

  Here, when the ratio L / D is set within the range of the present invention, the above-mentioned technical problem can be avoided and the torque improvement effect of the internal combustion engine in the inertia supercharging can be remarkably increased.

  In another aspect of the intake control device for an internal combustion engine of the present invention, the plate thickness of the inner pipe is thinner than the plate thickness of the intake passage.

  According to this aspect, the plate thickness of the inner pipe constituting the surge tank can be made thinner than the plate thickness of the intake passage. In a conventional diesel or gasoline engine that performs inertial supercharging, the outside of the intake passage and surge tank is at atmospheric pressure, and requires a strength that can withstand the pressure difference from the supercharging pressure due to inertial supercharging. In order to meet the requirements, it was necessary to increase the thickness of the intake passage. As a result, an increase in production costs and a deterioration in fuel consumption accompanying an increase in mass of the internal combustion engine have been caused.

  On the other hand, in this aspect, the surge tank is configured to include an inner pipe connected to the intake passage and an outer pipe formed to cover the periphery of the inner pipe. In the passage through which the gas passes (ie, the inner pipe), during the inertia supercharging, the intake passage and Since the same supercharging pressure as that of the inner pipe is applied, the force generated from the pressure difference between the inner side and the outer side of the inner pipe is reduced, and the required strength of the inner pipe is also reduced as compared with the conventional type. Therefore, by configuring in this way, while maintaining the strength that the inner tube can withstand the supercharging pressure, the plate pressure is made as thin as possible, thereby reducing the production cost and the fuel consumption associated with the reduction in mass. It is possible to realize the improvement.

  In this aspect, preferably, in the portion where the inner pipe of the surge tank is connected to the intake passage on the downstream side, at least a step due to the difference in the plate thickness at both inner diameters does not occur. It is preferable to be configured.

  In another aspect of the intake control device for an internal combustion engine of the present invention, the inner pipe is made of resin.

  According to this aspect, the inner wall of the inner pipe constituting the surge tank can be made of a resin having a low mass and a low cost as compared with the material forming the wall surface of the intake passage in the conventional internal combustion engine.

  According to this aspect, since the surge tank includes the inner pipe connected to the intake passage and the outer pipe formed so as to cover the periphery of the inner pipe, the intake tank covered by the outer pipe is configured. In the passage through which the gas passes (ie, the inner pipe), during the inertia supercharging, the intake passage and Since the same supercharging pressure as that of the inner pipe is applied, the force generated by the pressure difference between the inner and outer sides of the inner pipe is reduced, and the required strength of the inner pipe is also higher than that of the intake passage in the conventional internal combustion engine. Can be kept small. Thus, by configuring in this way, it is possible to realize a reduction in production cost and an improvement in fuel consumption accompanying a reduction in mass while maintaining the strength that the inner tube can withstand the supercharging pressure.

  In this aspect, preferably, in the portion where the inner pipe of the surge tank is connected to the downstream intake passage, at least a step due to the difference in material between the inner diameters is not generated. It is preferable that

  Another aspect of the intake control device for an internal combustion engine of the present invention is a tapered shape in which the inner diameter of the upstream end portion of the outer tube decreases toward the end portion, and the downstream end portion of the inner tube has a tapered shape. The intake control device for the internal combustion engine is mounted on the vehicle so as to be on the upper side.

  According to this aspect, in the diesel or gasoline engine in which inertial supercharging is performed, the condensed water generated when the intake air is cooled by the intercooler is removed from the closed end (that is, the outer pipe and the outer wall of the inner pipe). Can be prevented appropriately. Typically, the generated condensed water is stored in a lower part of an intercooler mounted on the lower part of the vehicle, and a part communicating with the inside of the cylinder on the downstream side of the intake control valve in the intake passage due to inertia supercharging (i.e., When the intake manifold is at a negative pressure, suction is performed.

  Therefore, with this configuration, the generated condensed water is promoted to flow into the intercooler via the intake passage on the upstream side of the surge tank, and as a result, the condensed water accumulates in the surge tank. Such problems as corrosion of the surge tank, breakage due to freezing of condensed water, noise, and reduction of the volumetric efficiency improvement effect of inertia supercharging due to volume reduction in the surge tank can be suitably prevented.

  Here, mounting with the end on the downstream side of the inner pipe facing upward means that the end on the downstream side (that is, on the downstream side of the inner pipe is compared with the end on the upstream side of the surge tank). How is the end) pointed at that the condensed water condensed at least in the surge tank is mounted high enough to flow into the upstream end and can enjoy the above-mentioned effects? It may be installed.

Another aspect of the intake control device for an internal combustion engine according to the present invention is provided with at least one opening at a lower portion when mounted on a vehicle at a downstream end portion of the outer pipe, and through the opening. Thus, the intake passage is connected to a portion communicating with the inside of the cylinder on the downstream side of the intake control valve in the intake passage. According to this aspect, the intake air is cooled by the intercooler in the diesel or gasoline engine in which inertia supercharging is performed. Therefore, it is possible to suitably prevent problems associated with the condensate water generated at the time of accumulation at the closed end in the surge tank (that is, the connecting portion between the outer tube and the outer wall of the inner tube). Furthermore, when the internal combustion engine is mounted on a vehicle, the condensed water condensed in the surge tank can be suitably flowed into the intake manifold without restricting the mounting mode.

  Therefore, with this configuration, the generated condensed water is promoted to flow into the intercooler via the intake passage on the upstream side of the surge tank, and as a result, the condensed water accumulates in the surge tank. Such problems as corrosion of the surge tank, breakage due to freezing of condensed water, noise, and reduction of the volumetric efficiency improvement effect of inertia supercharging due to volume reduction in the surge tank can be suitably prevented.

<Embodiment of the Invention>
Various preferred embodiments of the present invention will be described below with reference to the drawings.
<Basic configuration>
First, a basic configuration of an engine system 10 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram conceptually showing the configuration of the engine system 10.

  In FIG. 1, an engine system 10 is mounted on a vehicle (not shown) and includes an ECU 100 and an engine 200.

  The ECU 100 is an electronic control unit that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like and is configured to be able to control the entire operation of the engine 200.

  The engine 200 is an in-line four-cylinder diesel engine that is an example of an “internal combustion engine” according to the present invention that uses light oil as fuel. The outline of the engine 200 will be described. The engine 200 has a configuration in which four cylinders 202 are arranged in parallel in a cylinder block 201. In the compression stroke in each cylinder, the force generated when the mixture of the fuel and the intake air directly injected into the cylinder in the compression stroke or the intake stroke is compressed and spontaneously ignited is not shown. This is converted into rotational movement of a crankshaft (not shown) via a piston and a connecting rod. The rotation of the crankshaft is transmitted to drive wheels of a vehicle on which the engine system 10 is mounted, and the vehicle can travel. Below, the principal part structure of the engine 200 is demonstrated with a part of the operation | movement. Since the configurations of the individual cylinders 202 are equal to each other, only one cylinder 202 will be described here.

  In FIG. 1, intake air, which is air guided from the outside, is supplied to a surge tank 205 whose inside communicates with the intake pipe 204 via an intake pipe 204 which is an example of an “intake passage” according to the present invention. It has a configuration. The surge tank 205 suppresses irregular pulsation of the intake air supplied while appropriately receiving a turbocharger operation described later, and stably supplies the intake air to the downstream side (that is, the cylinder 202 side). At the same time, the storage means is configured to function as an example of the “phase inversion means” according to the present invention at the time of executing the impulse charge described later. However, since the intake air is basically supplied to the cylinder 202 while pulsating to a greater or lesser extent, the intake air passing through the surge tank 205 is also a kind of pulsation wave.

  Here, with reference to FIG. 2 to FIG. 4, the configuration of the surge tank 205 and its peripheral part will be supplemented. Here, FIGS. 2 a to 4 are schematic cross-sectional views of the periphery of the surge tank 205 along the intake pipe 204. FIG. 2 b is a schematic cross-sectional view in a direction intersecting with the intake pipe of the surge tank 205. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In FIG. 2a, the surge tank 205 is an intake air storage volume connected to the upstream pipeline 204a on the upstream side and to the downstream pipeline 204b on the downstream side thereof, and is connected to the upstream pipeline 204a. An outer pipe 205a that is connected and has a length in the radial direction (that is, a direction intersecting with the extending direction of the intake pipe 204) larger than the radial length in the upstream pipe line 204a and the downstream pipe line 204b; The inner pipe 205b is connected to the path 204b and has a radial length equal to the radial length of the upstream pipe 204a and the downstream pipe 204b. Note that the upstream end of the inner tube 205b is an open end, and preferably the shape is a funnel-shaped configuration in which the tip expands from the vicinity of the end toward the end. The downstream end of the outer tube 205a forms a closed end connected to the outer wall of the inner tube 205b. The upstream pipe line 204a and the downstream pipe line 204b are part of the intake pipe 204, respectively. In addition, supplementally, the outer pipe 205a constituting the surge tank 205 has a substantially circular cross-sectional shape that intersects with the extending direction of the intake pipe 204, and the upstream pipe line 204a and the downstream pipe line 204b are This is a tubular member having a circular cross section. Therefore, the cross-sectional area of the outer pipe 205a in the cross section (that is, the cross-sectional area of the cross section in the surge tank 205) is sufficiently large with respect to the upstream pipe line 204a and the downstream pipe line 204b.

  Further, as shown in FIGS. 2a and 2b, the inner tube 205b is preferably provided with a stay structure between the inner tube 205b and the outer tube 205a at a predetermined position on the outer wall. The stay structure may be at least a structure capable of suppressing the vibration of the inner pipe 205b due to the pulsation of intake air accompanying inertial supercharging, which will be described in detail later, and the destruction or wear of the inner pipe 205b due to the vibration. Any form in such a range can be taken.

  As shown in FIG. 3, preferably, in the surge tank 205, the distance a between the open end of the inner pipe 205b and the connection portion between the upstream pipe 204a and the outer pipe 205a corresponding to the upstream end of the surge tank 205 is shown. Is preferably configured to be larger than the radial length (that is, the inner diameter) d of the inner tube 205b and smaller than twice d. Further, as shown in FIG. 4, preferably, in the surge tank 205, the central axis of the open end of the inner pipe 205b and the central axis of the upstream pipe line 204a are configured in the same straight line. preferable.

  Returning to FIG. 1, on the downstream side of the surge tank 205 (that is, on the cylinder 202 side), the downstream pipe line 204b is connected to the communication pipe 206, and communicates with the communication pipe 206 therein. The communication pipe 206 communicates with each intake port (not shown) of each cylinder 202, and the intake air guided to the intake pipe 204 is guided to the intake port corresponding to each cylinder via the communication pipe 206. It is configured to be written. Two intake ports are provided for each cylinder 202, and each intake port is configured to communicate with the inside of the cylinder 202.

  The communication state between the intake port and the cylinder 202 is controlled by an intake valve 207 provided at each intake port. The intake valve 207 is fixed to the intake camshaft 208 that rotates in conjunction with the crankshaft. The cam profile of the intake cam 209 that has an elliptical cross section perpendicular to the extending direction of the intake camshaft 208 (in short, The opening / closing characteristics are defined according to the shape), and the intake port and the inside of the cylinder 202 can communicate with each other when the valve is opened. As described above, in the engine 200, the communication pipe 206 is aggregated on the upstream side of the portion corresponding to each cylinder 202 (more specifically, the intake port), and is connected to the surge tank 205 via the downstream pipe line 204b. The communication pipe 206 constitutes an example of the “intake passage” according to the present invention together with the intake pipe 204.

  A fuel injection valve as a part of the in-cylinder injector 203 is exposed inside the cylinder 202, and is configured so that light oil as fuel can be directly injected into the high-temperature and high-pressure cylinder. Here, the fuel is stored in a fuel tank (not shown). The fuel stored in the fuel tank is pumped out of the fuel tank by the action of a feed pump (not shown) and is pumped to a high pressure pump (not shown) through a low pressure pipe (not shown). This high pressure pump is configured to be able to supply fuel to the common rail 203A. The high-pressure pump can take various known modes, and the details thereof will be omitted here.

  The common rail 203A is electrically connected to the ECU 100, and is configured to store high pressure fuel supplied from the upstream side (that is, the high pressure pump side) up to a target rail pressure set by the ECU 100. It is. The common rail 203A is provided with a rail pressure sensor capable of detecting the rail pressure and a pressure limiter for limiting the amount of fuel accumulated so that the rail pressure does not exceed the upper limit value. The illustration is omitted. The injector 203 is mounted for each cylinder 202, and each is connected to the common rail 203A via the high-pressure delivery 203B.

  Here, to supplement the configuration of the injector 203, the injector 203 includes an electromagnetic valve that operates based on a command supplied from the ECU 100, and a nozzle (both not shown) that injects fuel when the electromagnetic valve is energized. Prepare. The solenoid valve is configured to be able to control the communication state between the pressure chamber to which the high pressure fuel of the common rail 203A is applied and the low pressure side low pressure passage connected to the pressure chamber. The pressurizing chamber and the low pressure passage are communicated with each other, and the pressurizing chamber and the low pressure passage are shut off from each other when energization is stopped.

  On the other hand, the nozzle has a built-in needle for opening and closing the nozzle hole, and the fuel pressure in the pressure chamber urges the needle in the valve closing direction (direction in which the nozzle hole is closed). Accordingly, when the solenoid chamber is energized, the pressurizing chamber communicates with the low-pressure passage, and when the fuel pressure in the pressure chamber decreases, the needle rises in the nozzle and opens (opens the nozzle hole), thereby causing the common rail 203A. The high-pressure fuel supplied more can be injected from the injection hole. In addition, when the energization of the solenoid valve is stopped, the pressurization chamber and the low pressure passage are cut off from each other and the fuel pressure in the pressure chamber rises, and the needle is lowered in the nozzle to close the valve, thereby terminating the injection. It has become. In addition, such a structure is an example, for example, the fuel injection process itself may be electronically controlled (that is, fuel is injected without using pressure as a medium).

  Here, according to the injector 203, it is possible to precisely control the fuel injection amount. In the engine 200, the fuel corresponding to the target injection amount is supplied to the fuel in each cylinder 202 via the injector 203. Mainly equivalent to the difference between one or more pilot injections to promote premixing with intake air (of course, also to prevent rapid temperature rise in the combustion chamber) and the target injection amount and pilot injection amount It becomes the structure divided | segmented into injection and injecting.

  Note that the high-pressure pump, the common rail 203A, the high-pressure delivery 203B, and the injector 203 may be configured as an integrated common rail system. Further, the mode for injecting fuel into the high-temperature and high-pressure cylinder is not limited to those exemplified here, and various known modes may be adopted.

  In any case, the air-fuel mixture formed in the cylinder 202 is self-ignited and burned in the compression stroke, and is opened and closed in conjunction with opening and closing of the intake valve 207 as a burned gas or a partially unburned air-fuel mixture. When the exhaust valve 210 is opened, exhaust gas is guided to the exhaust manifold 213 through an exhaust port (not shown). The exhaust valve 210 is fixed to the exhaust camshaft 211 that rotates in conjunction with the crankshaft, and the cam profile of the exhaust cam 212 having an elliptical cross section perpendicular to the extending direction of the exhaust camshaft 211 (in short, The opening / closing characteristics are defined according to the shape), and the exhaust port and the cylinder 202 can be communicated with each other when the valve is opened. The exhaust gas collected in the exhaust manifold 213 is supplied to the exhaust pipe 214 communicating with the exhaust manifold 213.

  A turbine 216 is installed in the exhaust pipe 214 so as to be accommodated in the turbine housing 215. The turbine 216 is a rotary impeller configured to be rotatable about a predetermined rotation axis by the pressure of exhaust gas (that is, exhaust pressure) guided to the exhaust pipe 214. The rotating shaft of the turbine 216 is shared with the compressor 218 installed in the intake pipe 204 so as to be accommodated in the compressor housing 217. When the turbine 216 is rotated by exhaust pressure, the compressor 218 is also centered on the rotating shaft. It is configured to rotate.

  The “supercharger” according to the present invention is configured so that the compressor 218 can supply the intake air sucked into the intake pipe 204 from the outside via the air cleaner 219 to the downstream side by the pressure accompanying the rotation. Is a pressure feeding means as an example. The so-called supercharging is realized by the pressure-feeding effect of the intake air by the compressor 218. That is, in the engine 200, the turbine 216 and the compressor 218 constitute a kind of turbocharger. In the following description, the term “turbocharger” will be used as appropriate as a comprehensive concept including the turbine 216 and the compressor 217.

  Between the air cleaner 219 and the compressor 218, a hot wire type air flow meter 220 capable of detecting the mass flow rate of the intake air is installed. The air flow meter 220 is electrically connected to the ECU 100, and the detected intake air amount Ga is grasped by the ECU 100 at a constant or indefinite period. In the present embodiment, the detected intake air amount Ga has a unique relationship with the amount of intake air sucked into the cylinder 202 (that is, the intake air amount), and defines the actual load of the engine 200. Treated as an index value.

  In the intake pipe 204, an intercooler 221 is installed on the downstream side of the compressor 218 and the upstream side of the surge tank 205. The intercooler 221 has a heat exchange wall in the interior thereof, and when supercharged intake air passes (of course, the same is true in a low-speed region where the compressor 218 does not act substantially). 2 is an example of the “intake air cooling means” according to the present invention configured to be able to cool the intake air by heat exchange via the heat exchange wall. In the engine 200, the intake air density can be increased by the cooling by the intercooler 221, so that supercharging via the compressor 217 can be performed more efficiently.

  Between the intercooler 221 and the surge tank 205, a diesel throttle valve 222 capable of adjusting the amount of intake air supplied to the surge tank 205 is disposed. The diesel throttle valve 222 is a rotary valve that is electrically connected to the ECU 100 and is configured to be rotatable by a driving force supplied from a throttle valve motor 223 that is controlled by the ECU 100. The rotational position is continuously controlled from the fully closed position where the upstream portion and the downstream portion of the intake pipe 204 are substantially blocked to the fully open position where the intake pipe 204 is communicated almost entirely. Thus, in the engine 200, the diesel throttle valve 222 and the throttle valve motor 223 constitute a kind of electronically controlled throttle device.

  Engine 200 is a diesel engine, and its output is controlled through injection amount increase / decrease control, unlike air-fuel ratio control (fuel injection control based on intake air amount) in an engine using gasoline or the like as fuel. The Accordingly, the amount of intake air sucked through the diesel throttle valve 222 is not substantially limited at least on the upper limit side, and the diesel throttle valve 222 is basically used in most regions of the engine 200 operation period. Therefore, it is controlled to the fully open position.

  The required load of the engine 200 is determined according to an accelerator opening Acc that is an operation amount (that is, an operation amount by a driver) of an accelerator pedal (not shown). The accelerator opening Acc is detected by the accelerator opening sensor 11 and is grasped at a constant or indefinite period by the ECU 100 electrically connected to the accelerator opening sensor 11. In general, the smaller the accelerator opening, the smaller the required load, and the larger the accelerator opening, the larger the required load. Since the magnitude of the required load correlates with the magnitude of the required output, in the engine system 10, the engine required output changes in accordance with the accelerator opening Acc.

  On the other hand, the aggregated portion of the communication pipe 206 (that is, the portion upstream of the branch portion branched to the individual cylinders 202 (surge tank 205 side and connected to the downstream pipeline 204b)) One impulse valve 224 is provided. The impulse valve 224 has an opening degree that is defined according to the position of a valve body 224A, which will be described later, and a fully closed opening degree that blocks communication between the downstream pipe line 204b (primarily the surge tank 205) and the communication pipe 206. The “intake air” according to the present invention is configured to continuously change between the downstream opening 204b (primarily the surge tank 205) and the fully open opening that allows the communication pipe 206 to communicate almost entirely. It is an electromagnetic control valve as an example of a “control valve”. The impulse valve 224 may be provided in the downstream pipe line 204b.

  Here, the details of the impulse valve 224 will be described with reference to FIG. FIG. 3 is a schematic cross-sectional view around the impulse valve 224. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In FIG. 3, the impulse valve 224 is configured as a valve device including a valve body 224A, a rotating shaft 224B, a drive motor 224C, and a drive circuit 224D.

  The valve body 224A is a rotating body configured to be rotatable in a plane in the illustrated cross section.

  The rotation shaft 224B is a shaft body that defines the rotation center of the valve body 224A, and is connected to the rotation shaft of the drive motor 224C.

  The drive motor 224C is a three-phase AC motor, and the above-described rotation shaft 224B is connected to the rotation shaft thereof. The drive motor 224C is connected to the rotation shaft, and a rotor (not shown) having a permanent magnet is rotated by the action of a magnetic field formed in the drive motor 224C by the drive circuit 224D. The driving force is generated.

  The drive circuit 224D is a power control circuit configured to be able to control the state of the magnetic field formed in the drive motor 224C. The drive circuit 224D is electrically connected to the ECU 100, and is configured such that its operation is controlled by the ECU 100 to the upper level.

  Here, the position of the valve body 224A that defines the opening degree of the impulse valve 224 can be regarded as continuous (or practically continuous) between the illustrated fully closed position CL and the illustrated fully opened position OP in normal times. Controlled in steps). The fully closed position CL is a position corresponding to the above-described fully closed opening, and the fully open position OP is a position corresponding to the above fully opened opening. Supplementally, the reference position of the valve body 224A of the impulse valve 224 in the normal state (that is, the non-driving position and the default position) is the fully closed position. The position of the valve body 224A is continuously controlled in a range from the reference position to an opening angle of 90 ° in the clockwise direction (that is, corresponding to the fully open position).

  The ECU 100 controls the drive circuit 224D so that the valve body 224A stops at a target position (target opening angle) corresponding to the target opening of the impulse valve 224. As a result, power is supplied from the drive circuit 224D, and the rotor of the drive motor 224C is rotated to a position corresponding to the target position or held at a position corresponding to the target position in the drive motor 224C. A magnetic field is generated, and the valve body 224A indirectly fixed to the rotor finally stops at the target position. Note that the valve body 224A can rotate both in the clockwise direction and in the counterclockwise direction within the control range of the opening angle described above. As described above, the engine 200 is provided with the impulse valve 224 on the downstream side of the diesel throttle valve 222, so that whether or not intake air is supplied to each cylinder 202 is controlled according to the open / close state of the impulse valve 224. It has a configuration.

  Returning to FIG. 1, a rotation angle sensor 225 is installed in the communication pipe 206 in the vicinity of the impulse valve 224. The rotation angle sensor 225 is a so-called resolver that can detect an angle by utilizing a change in the phase of the voltage output from the two-phase coil of the rotor, and is an opening degree of the impulse valve 224 (that is, unambiguous). In particular, the position of the valve body 224A can be detected. Further, the rotation angle sensor 225 is electrically connected to the ECU 100, and the detected opening of the impulse valve 224 is grasped by the ECU 100 at a constant or indefinite period. The means for detecting the opening degree of the impulse valve 224 is not limited to the resolver.

  A DPF (Diesel Particulate Filter) 226 is installed in the exhaust pipe 214. The DPF 226 is configured to be able to collect and purify PM (Particulate Matter: particulate matter) discharged from the engine 200. A water temperature sensor 227 is disposed in the cylinder block 201 that houses the cylinder 202. Inside the cylinder block 201, a water jacket serving as a flow path of cooling water (for example, LLC) for cooling the cylinder 202 is stretched, and the cooling water acts on a circulation system (not shown) inside the water jacket. Is circulated by The water temperature sensor 227 is configured such that a part of the detection terminal is exposed inside the water jacket and can detect the temperature of the cooling water. The water temperature sensor 227 is electrically connected to the ECU 100, and the detected cooling water temperature is grasped by the ECU 100 at a constant or indefinite period.

  In the engine system 10 according to the present embodiment, the engine 200 as a diesel engine is employed as an example of the “internal combustion engine” according to the present invention. However, the internal combustion engine according to the present invention refers only to a diesel engine. Of course, a gasoline engine, an engine using alcohol mixed fuel, or the like may be used. Further, for the purpose of preventing the explanation from being complicated, the engine 200 according to the present embodiment is not equipped with an exhaust gas recirculation device such as an EGR device. However, as a preferred embodiment, the engine 200 is equipped with an exhaust gas recirculation device. It may be. Here, in view of the configuration in which the exhaust gas recirculation device is not mounted, in the engine 200 in the present embodiment, the intake air that is sucked into each cylinder 202 via the intake port is only by the intake air that is guided via the intake pipe 204. Composed.

Thus, in the engine system 10 according to this embodiment, the intake pipe 204 (including the upstream pipe line 204a and the downstream pipe line 204b), the compressor 218, the intercooler 221, the surge tank 205, the communication pipe 206, and the impulse valve 224 includes an example of an “intake device for an internal combustion engine” according to the present invention. In particular, a communication pipe 206 is provided in each cylinder on the downstream side of the impulse valve 224 located on the downstream side of the surge tank 205. On the other hand, it is configured as a so-called one-valve in-maniless intake system that branches.
<Basic operation>
In the engine system 10, impulse charge is executed when the engine speed NE of the engine 200 is in a predetermined impulse charge region. Here, the impulse charge refers to inertial supercharging utilizing intake air pulsation caused by opening and closing of the impulse valve 224. More specifically, when one cylinder 202 reaches the intake stroke with the impulse valve 224 closed, the intake valve 207 of the cylinder 202 is opened, and the piston of the cylinder 202 starts to descend. At this time, since the impulse valve 224 is closed, the internal pressure of the communication pipe 206 becomes a negative pressure, and the pressure difference from the internal pressure of the downstream pipe 204b maintained at atmospheric pressure or higher by atmospheric pressure or supercharging. Expands.

  If the impulse valve 224 is opened in such a state (that is, opened during a valve opening period after the valve opening timing of the intake valve 207), it corresponds to the downstream pipe line 204b (uniquely the surge tank 205). The inside of the cylinder 202 (that is, the cylinder in the intake stroke at that time) communicates with the inside of the cylinder 202, and the intake air flows into the combustion chamber inside the cylinder 202 at once as the intake air via the impulse valve 224.

  On the other hand, the communication pipe 206 is a so-called open end at the communication part with the combustion chamber, and the positive pressure wave caused by the inflow of the intake air into the combustion chamber is reflected by the combustion chamber, so that the phase is inverted. It becomes a pressure wave (that is, an example of “pulsation wave corresponding to pulsation” according to the present invention). The negative pressure wave reaches the surge tank 205 via the communication pipe 206, the impulse valve 224, and the downstream pipe line 204b in this order.

  In the present embodiment, the surge tank 205 has an inner diameter equal to that of the downstream pipe line 204b, and is connected to the inner pipe 205b corresponding to the extension of the downstream pipe line 204b and the upstream pipe line 204a. The outer pipe 205a has a sufficiently larger inner diameter than the upstream pipe 204a and the inner pipe 205b formed so as to cover the outer pipe 205a. Here, the upstream end of the inner tube 205b is also an open end, and has the effect of reflecting the above-described negative pressure wave.

  For this reason, the negative pressure wave that has reached the surge tank 205 is reflected at the upstream end of the inner pipe 205b, and is again converted into a positive pressure wave whose phase is reversed, the downstream pipe 204b, the intercooler 221a, the impulse valve 224, and the communication pipe. The combustion chamber is reached via 206. In other words, when the peak of the secondary positive pressure wave reaches the combustion chamber (or the intake valve 207) (not necessarily limited to that point, as long as the intake charging efficiency can be improved to some extent). If the intake valve 207 is closed, the pressure in the combustion chamber rises, and the intake charging efficiency is improved. Impulse charging using the impulse valve 224 is executed in this way.

  On the other hand, the surge tank 205 can invert the phase of a pulsating wave (a negative pressure wave that is a reflected wave of a positive pressure wave) due to its physical structure, and therefore pulsation caused by the distance from the intake valve 207 (or its vicinity). As long as wave attenuation does not become a problem in practice, or as long as other requirements such as installation restrictions are not violated, the installation position on the intake pipe 204 is relatively free.

  Here, the engine system 10 is provided with an intercooler 221a, and the intake air supplied into the cylinder 202 by impulse charging has increased in density from the beginning (compared to the case where at least the intercooler 221a is not provided). Increased). Therefore, the charging efficiency of intake air can be further improved by impulse charging.

  According to the surge tank 205 of the intake control device for an internal combustion engine according to the present invention, the inner pipe 205b that is an extension of the downstream pipe line 204b of the surge tank 205 and the periphery of the inner pipe 205b are primarily covered. Since the outer pipe 205a is configured, the gap around the intake passage 204 can be used effectively, and the outer pipe 205a can be formed based on the shape of the gap around the intake passage 204. For this reason, when the intake control device for an internal combustion engine according to the present invention is mounted on a vehicle, the mountability can be dramatically improved.

  Further, in the above-described inertia supercharging, the inner pipe 205b is formed so as to cover the periphery of the inner pipe 205b with respect to a technical problem that causes vibration due to intake air pulsation and noise. The outer pipe 205a can suitably suppress the degree of the leakage of the noise to the outside of the internal combustion engine.

  As described above, the distance a between the open end of the inner pipe 205b and the end of the upstream pipe line 204a is defined within a range that is larger than the inner diameter d of the inner pipe 205b and smaller than twice d. Therefore, on the one hand, the pressure of the pulsating wave from the open end of the inner pipe due to inertia supercharging escapes to the intake passage on the upstream side of the surge tank due to the distance between both being too close. Although the positive pressure wave generated by the reversal of the pressure wave is reduced, the situation is suitably prevented, and on the other hand, the above-mentioned book accompanying making the surge tank 205 into a double-pipe structure due to both distances being too long Although the remarkable effect in the intake control device for an internal combustion engine of the invention cannot be obtained, the situation can be suitably prevented.

Further, by configuring the central axis in the vicinity of at least the open end of the inner pipe 205b and the end of the upstream pipe line 204a to be on the same line, the flow of intake air flowing from the upstream side The efficiency of favorably flowing into the inner pipe 205b from the end of the pipe line 204a can be improved, and the increase in intake pressure loss and the increase in pump loss due to the fact that the flow of intake air does not flow into the inner pipe 205b can be suitably achieved. Can be suppressed. In addition, by configuring the open end of the inner pipe 205b in a funnel shape in which its inner diameter increases as it approaches the end, it becomes possible to allow the flow of intake air to flow into the inner pipe 205b more appropriately, and to further reduce the intake pressure loss. This can be reduced.
<First Modification>
The configuration of the surge tank 205 ′ and its peripheral part according to the first modification of the present invention will be described with reference to FIGS. Here, FIGS. 6 and 7 a are schematic cross-sectional views of the periphery of the surge tank 205 ′ along the intake pipe 204. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In the description of the above-described embodiment, the basic configuration and the basic operation of the engine system 10 including the surge tank 205 have been described. However, in this modification, the engine system 10 is replaced with the surge tank 205. The surge tank 205 ′ provided will be described. The basic configuration and basic operation of the engine system 10 including the surge tank 205 ′ according to the present modified example are related to the above-described embodiment except for a notable difference between the surge tank 205 and the surge tank 205 ′ described in detail later. This is the same as the engine system 10.

  As shown in FIG. 6, the surge tank 205 ′ in the present modification is formed so that the inner diameter d2 of the end of the upstream pipe 204a is smaller than the inner diameter d of the inner pipe 205′b. In the vicinity of the end of the upstream pipe line 204a, the inner diameter decreases gradually as the end is approached.

  Further, as shown in FIG. 7a, the length L of the surge tank 205 ′ in the intake passage direction and the diameter of a circle having the same area as the cross-sectional area intersecting with the intake passage (that is, the surge tank 205 ′ It is preferable that the ratio L / D of the circular diameter (D) when the cross-sectional area is circular is 3 or more and 5 or less.

  Here, FIG. 7b schematically shows the relationship between the aforementioned ratio L / D and the engine torque (that is, shaft torque) in an engine system including a surge tank configured to comply with the ratio L / D. It is a graph. As shown in FIG. 7b, when the ratio L / D is between 3 and 5, the effect of improving the engine torque at the time of inertia supercharging is maximized. Here, when the ratio L / D becomes larger than necessary, the inner diameter of the surge tank 205 ′ becomes smaller, and the damping effect of the pressure pulsation as the surge tank is reduced. As a result, the volume effect in the inertia supercharging is improved. By reducing, the engine torque improvement effect is reduced. On the other hand, when the ratio L / D becomes smaller than necessary, the diameter required to provide the capacity necessary for having the function as a surge tank increases, and the formed surge tank 205 ′ is transferred to the vehicle. The mountability of will be significantly deteriorated. In the configuration of the surge tank 205 ′ of this modification, it is possible to significantly increase the engine torque improvement effect associated with inertial supercharging while suitably preventing such technical problems.

  Furthermore, as described above, the upstream side pipe line 204a is tapered toward the connection portion with the surge tank 205 ′, so that the flow of intake air from the upstream side of the intake passage 204 can flow inside the surge tank 205 ′. Since adjustment is made so as to be directed toward the radial center of the inner pipe 205′b, the intake air can be smoothly sent to the downstream pipe line 204b via the surge tank 205 ′, and intake pressure loss can be reduced. . Furthermore, the pulsation of the intake air due to the inertia supercharging can be suitably prevented from flowing back to the upstream pipe line 204a due to the aforementioned tapered shape, and the negative pressure wave from the impulse valve 224 is suitably reflected in the surge tank 205 ′. As a result, it is possible to further increase the effect of improving the volumetric efficiency at the time of inertia supercharging.

The configuration of the surge tank 205 ′ in this modification may be provided in place of the surge tank 205 provided in the engine system 10 in the embodiment as described above, and in the above-described embodiment and other modifications in a readable range. You may comprise combining as a structure which concerns on a surge tank or an element replaced with it. In that case, it is natural that not only the remarkable effects of the present modification but also the remarkable effects of the embodiment or other modifications can be exhibited.
<Second Modification>
The configuration of the surge tank 205 ″ and its peripheral part according to the second modification of the present invention will be described with reference to FIGS. 8 and 9 are schematic cross-sectional views of the periphery of the surge tank 205 ″ along the intake pipe 204. FIG. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In the description of the above-described embodiment, the basic configuration and the basic operation of the engine system 10 including the surge tank 205 have been described. However, in this modification, the engine system 10 is replaced with the surge tank 205. The surge tank 205 ″ provided will be described. The basic configuration and basic operation of the engine system 10 including the surge tank 205 ″ according to the present modification are the same as those in the above-described embodiment except for the remarkable difference between the surge tank 205 and the surge tank 205 ″ described later. This is the same as the engine system 10 according to the above.

  As shown in FIG. 8, the surge tank 205 ″ in this modification has a plate thickness of the inner pipe 205 ″ b compared to the plate thickness of the intake passage 204 or the outer pipe 205 ″ a. And thinly formed (dotted line portion in FIG. 8). Here, the plate thickness of the inner tube 205 ″ b is based on the difference between the air pressure in the space between the inner tube 205 ″ b and the outer tube 205 ″ a and the air pressure inside the inner tube 205 ″ b. It is sufficient that it has a strength that does not cause breakage with respect to the generated force, and is formed to be considerably thinner than the plate thickness of the intake passage 204 or the plate thickness of the outer tube 205''a, As a result, it is possible to bring about favorable effects such as cost reduction of materials and improvement of fuel consumption accompanying mass reduction when manufacturing the surge tank 205 ″.

  On the other hand, as shown in FIG. 9, the surge tank 205 ″ in the present modification may be formed of a resin material for the inner tube 205 ″ b. Here, being formed of resin means a force generated from a difference between the air pressure in the space between the inner tube 205 ″ b and the outer tube 205 ″ a and the air pressure in the inner tube 205 ″ b. It is made of a resin that has a strength that does not cause destruction, and the mass is considerably reduced compared to a conventional surge tank or intake passage that is typically made of a metal material. It is desirable that Also in the surge tank 205 ″ configured in this way, it is possible to enjoy suitable effects such as cost reduction of materials at the time of manufacture and improvement of fuel consumption accompanying mass reduction.

  In the surge tank 205 '' having a double-pipe structure according to the present invention, the force generated by the pressure difference between the supercharging pressure due to the inertia supercharging and the atmospheric pressure outside the intake system is not damaged. Although it is required to have strength, in particular, in the inner pipe 205''b constituting the surge tank 205 '', the supercharging pressure accompanying inertial supercharging, the inner pipe 205''b, Since the force applied due to the pressure difference from the air pressure is reduced compared to, for example, the conventional surge tank or the outer tube 205''a of the surge tank 205 '' according to the present invention, the required strength is It is set relatively small. Therefore, by reducing the plate thickness of the inner tube 205''b, or by forming it with a resin that is low in mass and low in cost but inferior in strength, the manufacturing cost can be reduced compared to a conventional surge tank, It is possible to improve the fuel consumption associated with the reduction in mass when mounted on a vehicle.

  Further, at the connection portion between the inner pipe 205 ″ b and the downstream pipe line 204a in this modification, at least the inner wall portion is configured not to have a step or a projection due to a difference in thickness or material. It is preferable that By being configured in this manner, the flow of the intake air is disturbed at the connecting portion, but the situation can be suitably suppressed, and the smooth intake air passage is performed.

The configuration of the surge tank 205 '' in the present modification may be provided in place of the surge tank 205 provided in the engine system 10 in the embodiment as described above, and the above-described embodiment and other modifications are within the readable range. And may be configured in combination as a configuration related to the surge tank in FIG. In that case, it is natural that not only the remarkable effects of the present modification but also the remarkable effects of the embodiment or other modifications can be exhibited.
<Third Modification>
The configuration of the surge tank 205 ′ ″ and its peripheral part according to the third modification of the present invention will be described with reference to FIGS. FIG. 10 is a schematic cross-sectional view of the periphery of the surge tank 205 ′ ″ along the intake pipe 204. As shown in FIG. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In the description of the above-described embodiment, the basic configuration and the basic operation of the engine system 10 including the surge tank 205 have been described. However, in this modification, the engine system 10 is replaced with the surge tank 205. The surge tank 205 ″ ′ provided will be described. The basic configuration and basic operation of the engine system 10 including the surge tank 205 ′ ″ according to the present modification are the same as those described above except for a notable difference between the surge tank 205 and the surge tank 205 ′ ″ described in detail later. This is the same as the engine system 10 according to the embodiment.

  As shown in FIG. 10, the surge tank 205 ′ ″ in the present modification is such that the upstream end of the outer tube 205 ′ ″ a tapers toward the connecting portion with the upstream pipeline 204a. Is formed. Further, the engine system 10 including the surge tank 205 "" is mounted on the vehicle such that the downstream side of the surge tank 205 "" is located above and the upstream side is located relatively below.

  In the engine system 10 having a supercharger and performing inertial supercharging as shown in FIG. 1, condensed air is generated when the intake air is cooled in the intercooler 221, and the intake passage 204 and the surge tank are generated. There is a case where condensation occurs in 205 '' '. The condensed water condensed here is typically stored in a lower part of an intercooler 221 mounted in the lower part of the vehicle, and the communication pipe located downstream of the impulse valve becomes negative pressure due to inertia supercharging. In this case, the engine system 10 is configured to be sucked together with the intake air. As described above, the surge tank 205 ′ ″ in the present modification is configured so that the condensed water condensed in the surge tank 205 ′ ″ or the intake passage 204 on the downstream side preferably flows into the intercooler 221 as described above. And a tapered shape of the outer tube 205 ′ ″ a. Accordingly, it is possible to suitably suppress situations such as corrosion, noise, and capacity reduction of the surge tank 205 ″ ″ caused by the accumulation of condensed water in the surge tank 205 ″ ″.

The configuration of the surge tank 205 ′ ″ in the present modification may be provided in place of the surge tank 205 provided in the engine system 10 in the embodiment as described above. You may comprise combining as a structure which concerns on the surge tank in an example, or the element replaced with it. In that case, it is natural that not only the remarkable effects of the present modification but also the remarkable effects of the embodiment or other modifications can be exhibited.
<Fourth Modification>
The configuration of the surge tank 205 ″ ″ and its peripheral part according to the fourth modification of the present invention will be described with reference to FIGS. FIG. 11 is a schematic cross-sectional view of the periphery of the surge tank 205 ″ ″ along the intake pipe 204. In the figure, the same reference numerals are given to the same portions as those in FIG. 1, and the description thereof will be omitted as appropriate.

  In the description of the above-described embodiment, the basic configuration and the basic operation of the engine system 10 including the surge tank 205 have been described. However, in this modification, the engine system 10 is replaced with the surge tank 205. The surge tank 205 ″ ″ provided will be described. The basic configuration and basic operation of the engine system 10 including the surge tank 205 ″ ″ in the present modification are except for a notable difference between the surge tank 205 and the surge tank 205 ″ ″ described in detail later. This is the same as the engine system 10 according to the above-described embodiment.

  As shown in FIG. 11, in the engine system 10 including the surge tank 205 ″ ″ in the present modification, the upstream side of the surge tank 205 ″ ″ is located above, and the downstream side is located relatively below. So that it is mounted on the vehicle. Further, typically, an impulse in the intake passage 204 is formed through an opening at a portion corresponding to the lowermost portion when the vehicle is mounted, which corresponds to a closed end on the downstream side of the outer tube 205 ″ ″ a of the surge tank 205 ″ ″. It is connected to a part communicating with each cylinder 202 on the downstream side of the valve 224 (for example, a part typically used as an intake manifold such as the communication pipe 206). The condensate accumulated in the surge tank 205 '' '' can be preferably flowed into the intake manifold through the connection portion without depending on being sucked as the intake manifold becomes negative pressure. It can be done. In addition, for some reason, as described in the above-described third modification, for a suitable outflow of condensed water, even if the surge tank cannot be mounted on the vehicle so that the upstream side faces downward, Condensed water can be suitably discharged through the connection site with the intake manifold in this modification. Accordingly, it is possible to suitably suppress situations such as corrosion, noise, and capacity reduction of the surge tank 205 ″ ″ due to the accumulation of condensed water in the surge tank 205 ″ ″.

  The configuration of the surge tank 205 ″ ″ in the present modification may be provided in place of the surge tank 205 provided in the engine system 10 in the embodiment as described above. You may comprise combining as a structure which concerns on the surge tank in a modification, or the element replaced with it. In that case, it is natural that not only the remarkable effects of the present modification but also the remarkable effects of the embodiment or other modifications can be exhibited.

1 is a schematic configuration diagram conceptually showing a configuration of an engine system according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a portion around a surge tank along an intake passage and a schematic cross-sectional view in the radial direction of the surge tank in the engine system of FIG. 1. FIG. 2 is a schematic cross-sectional view of a portion around a surge tank along an intake passage in the engine system of FIG. 1. FIG. 2 is a schematic cross-sectional view of a portion around a surge tank along an intake passage in the engine system of FIG. 1. FIG. 2 is a schematic cross-sectional view around an impulse valve in the engine system of FIG. 1. It is typical sectional drawing of the surge tank periphery part along an intake passage concerning the 1st modification of the present invention. 6 is a schematic cross-sectional view of a portion around a surge tank along an intake passage and a graph schematically showing a relationship between a ratio L / D and an engine torque according to a first modification of the present invention. It is typical sectional drawing of the surge tank periphery part along an intake passage concerning the 2nd modification of the present invention. It is typical sectional drawing of the surge tank periphery part along an intake passage concerning the 2nd modification of the present invention. It is typical sectional drawing of the surge tank periphery part along an intake passage concerning the 3rd modification of the present invention. It is typical sectional drawing of the surge tank periphery part along an intake passage concerning the 4th modification of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Engine system, 100 ... ECU, 200 ... Engine, 202 ... Cylinder, 204 ... Intake passage, 205 ... Surge tank, 205a ... Outer pipe, 205b ... Inner pipe, 206 ... Communication pipe, 207 ... Intake valve, 216 ... Turbine 218 Compressor 221 Intercooler 222 Throttle valve 224 Impulse valve

Claims (6)

Mounted on the vehicle,
An intake passage communicating with the inside of the cylinder;
An intake control valve installed in the intake passage, capable of generating pulsation of intake air according to an open / closed state, and capable of adjusting an intake air amount as the intake air amount;
Phase inversion means installed on the upstream side of the intake control valve in the intake passage and for inverting the phase of a pulsating wave corresponding to the generated pulsation,
The phase inversion means includes (i) an outer pipe having a cross-sectional area that is larger than the cross-sectional area in the intake passage and a cross-sectional area that is in a direction crossing the intake passage. (Ii) an upstream end of the outer pipe is connected to the intake passage, and a downstream end is connected to the outside of the inner pipe. (Iii) an upstream end of the inner pipe is an open end inside the outer pipe, and a downstream end is connected to the intake passage; and (iv) an upstream side of the outer pipe distance a between the upstream end of the end portion of the intake passage connected to an end and the inner tube is greater than the inner diameter d of the inner tube, rather smaller than 2 times the inner diameter d of the inner tube ,
At least a central axis near the end of the intake passage connected to the upstream side of the outer pipe and at least a central axis near the upstream end of the inner pipe are arranged on the same line,
An intake control device for an internal combustion engine, characterized in that the inner diameter in the vicinity of the end of the intake passage connected to the upstream side of the outer pipe has a tapered shape that decreases toward the end . The ratio (L / D) between the length L of the outer tube and the diameter D of a circle having the same area as the cross-sectional area of the cross-section in the direction intersecting the intake passage of the outer tube is 3 or more and 5 or less The intake control device for an internal combustion engine according to claim 1 , wherein the intake control device is provided. The intake control device for an internal combustion engine according to claim 1 or 2 , wherein a thickness of the inner pipe is thinner than a thickness of the intake passage. The intake control device for an internal combustion engine according to claim 1 or 2 , wherein the inner pipe is made of resin. The inner pipe has a tapered shape that decreases in diameter toward the end, and the downstream end of the inner pipe is positioned higher than the upstream end of the inner pipe. The intake control apparatus for an internal combustion engine according to claim 1 , wherein the intake control apparatus for the internal combustion engine is mounted on the vehicle. The outer pipe is provided with at least one opening in a lower portion when mounted on the vehicle, and the outer pipe is arranged in the cylinder on the downstream side of the intake control valve in the intake passage through the opening. The intake control device for an internal combustion engine according to claim 1 , wherein the intake control device is connected to a portion communicating with the internal combustion engine.

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