JP5324262B2 - Intake device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To downsize an auxiliary intake passage while reducing the pressure loss of an intake flow in an auxiliary throttle valve and ensuring a necessary intake flow rate by the auxiliary intake passage. <P>SOLUTION: The air introduction side (90) of the throttle bore 81 of an auxiliary throttle device 80 is deviated to a side where the plate surface of an auxiliary throttle valve 84 is located on an intake downstream side by the valve opening movement of the auxiliary throttle valve 84 when viewed from a virtual plane perpendicular to the center axis of the rotation of the auxiliary throttle valve 84. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an intake device for an internal combustion engine, and more particularly to an intake device having an auxiliary intake system.

  As an intake device of an internal combustion engine (engine), a main intake passage for supplying intake air to each of a plurality of cylinders, a main throttle valve provided in the main intake passage, and the main intake valve on the downstream side of intake from the main throttle valve An intake device having an auxiliary intake passage that supplies intake air to the intake passage is known (for example, Patent Document 1).

  The auxiliary intake passage may be called an auxiliary intake passage or a bypass intake passage. Further, since idle control is performed by the intake air flowing through the auxiliary intake passage, the auxiliary intake passage may be referred to as a primary intake passage, and the main intake passage provided with the main throttle valve may be referred to as a secondary intake passage. However, in this specification, the secondary intake passage is referred to as a main intake passage, and the primary intake passage is referred to as a sub intake passage.

JP 2003-328882 A

  In the intake device as described above, a sub-throttle valve that variably sets the intake air flow rate in the sub-intake passage may be provided for idle speed and low load operation control. In such a case, separation of the intake flow in the sub-throttle valve portion is minimized to reduce the pressure loss of the intake flow in the sub-throttle valve portion, and the necessary intake air flow through the sub-intake passage is secured, and then the sub-intake It is particularly required for high-performance engines to downsize the passage and increase the main intake passage accordingly to increase the maximum intake air amount.

  The problem to be solved by the present invention is to reduce the pressure loss of the intake air flow in the auxiliary throttle valve portion, and to ensure the necessary intake air flow through the auxiliary intake passage and to downsize the auxiliary intake passage. .

An intake device for an internal combustion engine according to the present invention includes a main intake passage for supplying intake air to each of the plurality of cylinders, and provided et the main throttle valve in the main intake passage, the intake downstream side of said main throttle valve An intake device for an internal combustion engine having a sub-intake passage for supplying intake air to a main intake passage and a sub-throttle device for adjusting an intake flow rate in the sub-intake passage, wherein the sub-throttle device is rotationally displaced in a throttle bore A sub-throttle valve by a butterfly valve provided so that the air introduction side of the throttle bore is biased to the side where the plate surface of the sub-throttle valve becomes the downstream side of intake by the opening movement of the sub-throttle valve. ing.

  As an embodiment of an intake device for an internal combustion engine according to the present invention, the air introduction side of the throttle bore is constituted by an air introduction passage having a smaller diameter than the throttle bore, and the center of the air introduction passage is the center of the throttle bore. It is biased in the radial direction from the center.

  According to these configurations, the air introduction side of the throttle bore is biased to the side where the plate surface of the sub throttle valve becomes the downstream side of the intake due to the opening movement of the sub throttle valve. A lot flows. As a result, the intake air passes through the sub-throttle valve portion with a smooth streamline without causing much flow such as wraparound. As a result, the occurrence of separation or large turbulence in the intake flow is reduced, and the pressure loss (flow resistance) of the intake flow in the sub throttle valve portion is reduced.

  In the internal combustion engine intake device according to the present invention, preferably, the plate surface of the sub-throttle valve is moved by the opening movement of the sub-throttle valve when the rotation center axis of the sub-throttle valve is orthogonal to the virtual plane. A deflecting element for deflecting the flow of intake air is provided on the air introduction side of the throttle bore toward the intake air downstream side.

  According to this configuration, due to the deflecting action of the deflecting element, the intake air further flows so that the plate surface of the sub throttle valve becomes downstream of the intake air, and the pressure loss of the intake flow in the sub throttle valve portion is further increased. Further reduction.

  The intake device for an internal combustion engine according to the present invention has an intake chamber having an open breather passage. Preferably, the intake end of the throttle bore on the air introduction side is higher than the open position of the breather passage. Open in the chamber.

  According to this configuration, even if oil contained in blow-by gas or the like accumulates in the intake chamber, the oil does not flow to the throttle bore of the sub-throttle device, and contamination of the sub-throttle device is avoided.

  According to the intake device for an internal combustion engine according to the present invention, the intake air passes through the sub-throttle valve portion with a smooth streamline without causing much flow such as sneaking or the like, and separation or large turbulent flow is caused in the intake air flow. The occurrence is reduced, and the pressure loss of the intake flow in the sub throttle valve portion is reduced. As a result, the ease of the intake air flow in the auxiliary throttle valve portion is improved, and the required intake air flow rate in the auxiliary intake passage is secured, and the auxiliary intake passage can be downsized.

The figure which shows typically one Example of the intake device of the internal combustion engine by this invention. Sectional drawing of the principal part of the intake device by a present Example. Sectional drawing of the principal part of the intake device by other Examples.

  An embodiment of an intake device for an internal combustion engine according to the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, the multi-cylinder internal combustion engine of the present embodiment is a 5-cylinder internal combustion engine having # 1 cylinder 11, # 2 cylinder 12, # 3 cylinder 13, # 4 cylinder 14, and # 5 cylinder 15. It is. In the V-type engine, the # 1 cylinder 11 to the # 5 cylinder 15 are arranged in two symmetrical rows to form a 10-cylinder engine.

  Main intake passages 21 to 25 for each cylinder are connected to each of the # 1 cylinder 11 to # 5 cylinder 15. Each of the main intake passages 21 to 25 protrudes into a common main intake chamber 26 with a funnel 27, and intake air (main intake) is distributed and supplied from the main intake chamber 26.

  Although not shown in the drawing, the main intake chamber 26 is connected to an air cleaner by an intake duct, and takes in outside air from the air cleaner.

  Individual main throttle valves 31 to 35 are provided in the main intake passages 21 to 25 for each cylinder. The main throttle valves 31 to 35 are butterfly valves and are attached to a common valve shaft 36. The main throttle valves 31 to 35 open and close all at once, and are sucked into the # 1 cylinder 11 to the # 5 cylinder 15 through the main intake passages 21 to 25. Quantitatively adjust (measurement setting) the flow rate (intake air amount).

  Such a throttle mechanism is called a cylinder-by-cylinder throttle or a multiple throttle, and in this multiple throttle, the intake passage length from each throttle valve to the combustion chamber of each cylinder can be set short, so that the throttle opening change Responsiveness of actual intake air amount change due to.

  In addition, the diameter of the open end (maximum diameter portion) of the funnel 27 of each main intake passage 21 to 25 is larger than the diameter of the main throttle valves 31 to 35, and a large amount of intake air smoothly flows from the funnel 27 to the main intake passages 21 to 25. It has a structure that flows with a smooth streamline. The opening end of the funnel 27 is at a position higher than the opening position of the breather passage 100, which will be described later, with respect to the main intake chamber 26, and the oil in the blow-by gas collected at the bottom of the main intake chamber 26 flows into the main intake passages 21-25. It has a structure that avoids this.

  Individual fuel injection valves 41 to 45 are attached to each cylinder. The fuel injection valves 41 to 45 inject fuel into the main intake passages 21 to 25 on the intake downstream side of the main throttle valves 31 to 35.

  In the main intake passages 21 to 25 on the intake downstream side of the main throttle valves 31 to 35, auxiliary intake introduction ports 51 to 55 are opened. Individual branch passages 61 to 65 are connected to the auxiliary intake introduction ports 51 to 55, respectively, and the branch passages 61 to 65 communicate with a common auxiliary intake chamber 71. The auxiliary intake chamber 71 communicates with the collecting passage portion 73 through a communication port 72.

  Here, the auxiliary intake passage 70 is branched from the collecting passage portion 73 through the auxiliary intake chamber 71 from the intake downstream side of the collecting passage portion 73 and communicates with the main intake passages 21 to 25 of each cylinder. 65.

  As shown in FIG. 2, an auxiliary throttle device 80 is attached to the inlet portion of the auxiliary intake passage 70, that is, the inlet portion of the collecting passage portion 73. The sub-throttle device 80 has a throttle body 82, and the throttle body 82 is formed with a throttle bore 81 that extends in the vertical direction and communicates with the collecting passage portion 73.

  The throttle body 82 rotatably supports a butterfly valve type sub-throttle valve 84 by a valve shaft 83. The sub-throttle valve 84 is located in the throttle bore 81 and opens by rotating clockwise around the valve shaft 83 as viewed in FIG. 2, and the intake air flowing through the throttle bore 81 according to the valve opening angle. , In other words, the intake flow rate flowing through the auxiliary intake passage 70 is quantitatively set.

  The cross-sectional shape of the passage of the throttle bore 81 of this embodiment is circular, and the sub-throttle valve 84 is made of a circular plate material accordingly. The diameter of the auxiliary throttle valve 84 may be slightly smaller than the diameter of the main throttle valves 31 to 35, depending on the setting of the required auxiliary intake flow rate.

  The air introduction end (air inlet) of the throttle bore 81 is open to the upper surface of the throttle body 82, and the pipe mounting member 87 is sandwiched between the upper surface of the throttle body 82 and a seal annular member 86 with an O-ring 85 attached. Are attached by bolts 88.

  An air introduction pipe 89 is fixedly attached to the pipe attachment member 87. The air introduction pipe 89 has an inner diameter smaller than the inner diameter of the throttle bore 81 and communicates with the throttle bore 81 linearly. That is, the air introduction pipe 89 extends in the vertical direction like the throttle bore 81, has a circular passage cross-sectional shape, and defines an air introduction passage 90 having a smaller diameter than the throttle bore 81.

  The center Ca of the air introduction passage 90 is a radial direction (passage cross-sectional direction) from the center Cb of the throttle bore 81 when viewed in a virtual plane orthogonal to the rotation center axis of the sub throttle valve 84, that is, the center axis of the valve shaft 83. ), The opening of the sub throttle valve 84 causes the plate surface of the sub throttle valve 84 to be deviated by a predetermined amount (bias amount) e toward the intake downstream side (the right side as viewed in FIG. 2). This deviation amount e corresponds to ½ of the difference in diameter between the throttle bore 81 and the air introduction passage 90. On the deviation side, the geometry of the air introduction passage 90 inscribed in the throttle bore 81 when viewed in the axial projection plane. It is a common arrangement. The passage cross-sectional direction is a direction orthogonal to both the rotation center axis of the sub throttle valve 84 and the center axis of the throttle bore 81.

  This means that a virtual vertical extension line passing through the center Ca of the air introduction passage 90 passes through a portion of the sub throttle valve 84 that rotates to the intake downstream side.

  The upper end side of the air introduction pipe 89 passes through an opening 26 </ b> A formed at the bottom of the main intake chamber 26 and protrudes into the main intake chamber 26. A plug tube 93 made of a rubber-like elastic body is attached to the main intake chamber 26 by an attachment plate 92 attached by screws 91. The plug tube 93 is fitted to the outer periphery of the air introduction pipe 89 and is in pressure contact with the lower bottom surface of the main intake chamber 26 to establish an airtight connection between the main intake chamber 26 and the air introduction pipe 89.

  Since the air introduction pipe 89 protrudes from the bottom of the main intake chamber 26 and the plug tube 93 as a seal member, oil or the like in the blow-by gas accumulates in the bottom of the main intake chamber 26 or the gap between the plug tubes 93. However, entry of the oil or the like into the air introduction pipe 89 can be avoided.

  As described above, the center Ca of the air introduction passage 90 is moved to the center Cb of the throttle bore 81 by the opening movement of the sub throttle valve 84 so that the plate surface of the sub throttle valve 84 becomes the intake downstream side by a predetermined amount e. By being biased only, a large amount of intake air flows toward the biased side. As a result, the intake air passes through the sub-throttle valve 84 portion with a smooth streamline without causing much flow such as wraparound. This becomes remarkable on the bias side because the air introduction passage 90 is in a geometrical arrangement inscribed in the throttle bore 81 when viewed in the axial projection plane.

  As a result, the occurrence of separation or large turbulent flow in the intake flow at the sub throttle valve 84 portion is reduced, and the pressure loss (flow resistance) of the intake flow at the sub throttle valve 84 portion is reduced. As a result, the ease of intake air flow in the sub-throttle valve 84 is improved, and the sub-intake passage 70 can be downsized while ensuring the necessary intake air flow rate through the sub-intake passage 70. The main intake passages 21 to 25 can be enlarged by the amount corresponding to the downsizing of the auxiliary intake passage 70 to increase the maximum intake air amount.

  In the present embodiment, a breather passage 100 is opened at the bottom of the main intake chamber 26 as shown in FIG. The upper end of the air introduction pipe 89, in other words, the opening end on the air introduction side of the throttle bore 81 is at a position higher by a predetermined amount h than the opening position of the breather passage 100 with respect to the main intake chamber 26.

  Since the maximum level of oil in the blow-by gas accumulated at the bottom of the main intake chamber 26 is defined by the opening height of the breather passage 100 in the main intake chamber 26, the oil in the blow-by gas accumulated at the bottom of the main intake chamber 26 Can be prevented from flowing into the throttle bore 81. Thereby, oil pollution of the sub-throttle device 80 is avoided, and the operation reliability of the sub-throttle device 80 is improved.

  In FIG. 1, the main intake chamber 26 to which the main intake passages 21 to 25 are connected and the main intake chamber 26 to which the air introduction pipe 89 is connected are individually illustrated, but this is for convenience of illustration. Because, in fact, it is one and the same thing.

  FIG. 3 shows another embodiment of the intake device according to the present invention. 3, parts corresponding to those in FIG. 2 are denoted by the same reference numerals as those in FIG. 2, and description thereof is omitted.

  In this embodiment, a deflection element 95 is mounted in the throttle bore 81. The deflection element 95 is in an inclined arrangement, and the plate surface of the sub-throttle valve 84 is moved to the intake downstream side by opening movement of the sub-throttle valve 84 when the rotation center axis of the sub-throttle valve 84 is viewed in a virtual plane orthogonal The flow of intake air is deflected to the side, that is, the side where the center Ca of the air introduction passage 90 is deviated from the center Cb of the throttle bore 81.

  Due to the deflecting action of the deflecting element 95, the intake air further flows so that the plate surface of the auxiliary throttle valve 84 becomes downstream of the intake air, and the pressure loss of the intake air flow at the auxiliary throttle valve 84 portion is further reduced. To do. In addition, the dead space indicated by the symbol D in FIG. 3 is reduced, and separation of the intake flow is prevented, so that a larger intake flow rate can be secured.

  The intake device according to the present invention is not limited to the above-described embodiments, and can be changed without departing from the spirit of the present invention.

11-15 # 1 cylinder-# 5 cylinder 21-25 Main intake passage 26 Main intake chamber 31-35 Main throttle valve 41-45 Fuel injection valve 61-65 Branch passage 70 Sub intake passage 71 Sub intake chamber 73 Collecting passage portion 80 Sub throttle device 81 Throttle bore 83 Valve shaft 84 Sub throttle valve 89 Air introduction pipe 90 Air introduction passage 100 Breather passage

Claims (3)

A main intake passage for supplying each intake of a plurality of cylinders, the auxiliary intake supplies and the main intake passage provided et the main throttle valve, the intake air to the main air intake passage of an intake downstream side of said main throttle valve An intake device for an internal combustion engine having a passage and a sub-throttle device that adjusts the intake air flow rate of the sub-intake passage,
The sub-throttle device has a sub-throttle valve by a butterfly valve provided in the throttle bore so as to be capable of rotational displacement, and an air introduction passage for introducing air into the throttle bore is connected to the throttle bore. Due to the valve opening movement, the plate surface of the sub-throttle valve is biased toward the intake downstream side,
Further, a plate-shaped deflection element that deflects the flow of intake air toward the side where the plate surface of the sub-throttle valve becomes the downstream side of intake by the opening movement of the sub-throttle valve moves toward the downstream side of the intake side. An intake device for an internal combustion engine, wherein the plate surface of the sub-throttle valve is inclined so as to be biased toward the intake downstream side by opening movement .   2. The internal combustion engine according to claim 1, wherein the air introduction side of the throttle bore is constituted by an air introduction passage having a smaller diameter than the throttle bore, and the center of the air introduction passage is radially deviated from the center of the throttle bore. Engine intake system. An intake chamber in communication with the blowby gas passage;
3. The internal combustion engine according to claim 1, wherein an opening end of the throttle bore on an air introduction side opens into the intake chamber at a position higher than an opening position of the blow-by gas passage that opens into the intake chamber. Inhalation device.

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