JP5527793B2 - Compressed air supply device for internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine, and more particularly to a compressed air supply device for an internal combustion engine.

  Conventionally, in a vehicle equipped with an internal combustion engine, for example, in Patent Document 1, compressed air is stored in a pressure accumulating tank and the stored high-pressure compression is performed in order to improve deterioration of engine performance during a transition such as starting. By supplying air to the turbine of the turbocharger, the driving of the turbine is assisted.

  In addition, Knorr-Bremse has proposed a system called PBS (Pneumatic Boosting System), which uses high-pressure compressed air stored in a pressure accumulating tank provided in a vehicle to supercharge a turbocharger. It is intended to improve vehicle startability, acceleration, etc. by increasing torque by introducing it into the intake system of an engine to compensate for supercharging in extremely low speed regions where it cannot be expected.

  These technologies are technologies for solving a shortage of low-speed torque due to engine downsizing for realizing improvement in vehicle fuel efficiency and weight reduction.

JP 2002-161751 A

By the way, the above-described PBS has a configuration capable of directly supplying high-pressure compressed air to the combustion chamber of the engine, and thus is expected as a technology that can supplement supercharging relatively efficiently. The compressed air leaks to the intake passage other than the path from the compressed air supply section (supply nozzle) to the combustion chamber of the internal combustion engine because of the need to efficiently guide the compressed air to the combustion chamber of the internal combustion engine. Is provided with a butterfly valve or the like (to reduce dead volume), and an electric actuator or the like for driving the butterfly valve as shown in FIG. There is a situation that it is complicated and cost increases.
In addition, the actual situation regarding such an electric drive actuator and the like similarly exists in the technique described in Patent Document 1.

  The present invention has been made in view of such circumstances, and efficiently supplies high-pressure compressed air stored in a pressure accumulating tank to an intake passage of an internal combustion engine and to a combustion chamber while having a simple and inexpensive configuration. An object of the present invention is to provide a compressed air supply device for an internal combustion engine capable of performing

For this reason, the compressed air supply device for an internal combustion engine according to the present invention includes:
A compressed air supply device that supplies compressed air stored in an accumulator tank to an intake passage of an internal combustion engine in a predetermined operation state,
A shut-off valve interposed in the intake passage on the upstream side of the intake air from the compressed air supply portion that faces the intake passage, and when the compressed air is supplied to the intake passage, While configured to shut off the intake upstream side of the shutoff valve and the combustion chamber side of the internal combustion engine,
While using the high pressure of compressed air as a drive source for the opening and closing operation of the shut-off valve ,
The shut-off valve is a butterfly valve, and the butterfly valve is opened and closed by an injection pressure when compressed air is injected toward the butterfly valve .

  In the present invention, the rotation axis of the butterfly valve is offset with respect to the center of the intake passage so that the butterfly valve rotates in the original position direction when the injection of compressed air is stopped. Can be a feature.

  In the present invention, the jet opening surface of the jet nozzle for compressed air may be adjusted so as not to face the upstream side in the flow direction of the intake air.

  The present invention may be characterized in that at least one blade that receives the action of the injection pressure of the injected compressed air is disposed around the rotation axis of the butterfly valve, separately from the butterfly valve. .

  According to the present invention, a compressed air supply device for an internal combustion engine capable of efficiently supplying the compressed air stored in the pressure accumulating tank to the intake passage and the combustion chamber of the internal combustion engine while having a simple and inexpensive configuration. Can be provided.

1 is a diagram schematically showing an overall configuration of an internal combustion engine according to an embodiment of the present invention. It is a figure explaining the structure of the compressed air introduction part of Example 1 (before operation | movement: the time of valve opening of a butterfly valve is shown). It is a figure explaining the structure of the compressed air introduction part of Example 1 (in operation | movement: The mode that a butterfly valve transfers to a valve closing state by the start of compressed air injection supply is shown). It is a figure explaining the structure of the compressed air introduction part of Example 1 (after an action | operation: The mode that a butterfly valve returns to a valve opening state by a compressed air injection supply stop is shown). It is a figure for demonstrating the structure of the bearing part of the rotating shaft of the butterfly valve of Example 2. FIG. It is a figure explaining the structure of the compressed air introduction part of Example 3 (before operation | movement: the time of valve opening of a butterfly valve is shown). It is a figure explaining the structure of the compressed air introduction part of Example 3 (During operation | movement: The mode that a butterfly valve transfers to a valve closing state by the start of compressed air injection supply is shown). It is a figure explaining the structure of the compressed air introducing | transducing part of Example 3 (after operation | movement: The mode that a butterfly valve returns to a valve-opening state by compressed air injection supply stop is shown). (A) is the figure (figure seen from the intake downstream side) which showed an example of the structure which opens and closes a butterfly valve using the air cylinder of Example 4, (B) is a side view of (A). . It is a figure which shows an example of the structure of the butterfly valve by the conventional electric motor drive (figure seen from the intake downstream side).

  Hereinafter, a compressed air supply device for an internal combustion engine according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  In this embodiment, as an example of the internal combustion engine, for example, a diesel combustion engine can be used. However, the present invention is not limited to this, and an internal combustion engine using gasoline or other substances as fuel can be used.

  As shown in FIG. 1, a turbocharger 3 is interposed in the exhaust passage 2 of the internal combustion engine 1, and an exhaust turbine (not shown) disposed facing the exhaust passage 2 is rotationally driven by exhaust energy. As a result, a compressor impeller (not shown) disposed facing the intake passage 4 is rotationally driven to perform supercharging.

  Moreover, in this Embodiment, the system which can store the compressed air pressure | voltage-risen by predetermined pressure in the pressure accumulation tank 5 is provided. For example, a compressed air pressure accumulation system used for an air brake, an air suspension, or the like can be used.

  A compressed air introduction unit 10 to which a compressed air supply passage 5A from the pressure accumulation tank 5 is connected is provided downstream of the intercooler 6 interposed in the intake passage 4 of the internal combustion engine 1 according to the present embodiment. Has been. The compressed air supply passage 5A is provided with, for example, an on-off valve 5B, and the on-off valve 5B is controlled to be opened and closed by an ECU (not shown) in a predetermined operating state.

  Here, as shown in FIG. 2, the compressed air introduction unit 10 is provided with a butterfly valve 11 configured to be rotatable around a rotation shaft 12 and capable of opening and closing the intake passage 4. FIG. 2 shows the valve opening position of the butterfly valve 11 (a state where the intake passage 4 is opened).

  Further, as shown in FIG. 2, a compressed air supply nozzle (compressed air supply portion) 13 connected to the compressed air supply passage 5 </ b> A is disposed in the compressed air introduction portion 10 so as to protrude from the inner wall of the intake passage 4. Has been. The compressed air supply nozzle 13 is disposed so that the compressed air injected from the compressed air supply nozzle 13 has a component that flows along the opening / closing direction of the butterfly valve 11.

  When the on-off valve 5B is opened in accordance with a control signal from the ECU in a predetermined operation state (for example, at the time of starting acceleration), the compressed air stored in the pressure accumulating tank 5 passes through the compressed air supply passage 5A. The compressed air is supplied to the compressed air supply nozzle 13, and the compressed air is injected from the compressed air supply nozzle 13 in a direction to open the butterfly valve 11.

  As a result, the butterfly valve 11 is rotated to the valve closing position, and as shown in FIG. 3, the compressed air from the compressed air supply nozzle 13 is urged to the valve closing position. Yes.

  In such a closed state, the communication between the intake upstream side of the butterfly valve 11 and the intake downstream side of the butterfly valve 11 is interrupted, so that the compressed air supplied from the compressed air supply nozzle 13 is supplied to the butterfly valve 11. Outflow to the intake upstream side (intercooler 6 side) can be reliably prevented and efficiently led to the combustion chamber of the internal combustion engine 1.

  Thereby, for example, the intake air amount can be supplemented in a very low speed region where turbocharging of the turbocharger 3 cannot be expected, thereby increasing the torque of the internal combustion engine 1 and increasing the vehicle startability. Acceleration can be improved.

  When the operating state changes and the on-off valve 5B is closed according to the control signal from the ECU, the supply of compressed air from the pressure accumulation tank 5 is stopped.

  As a result, the urging in the valve closing direction to the butterfly valve 11 by the compressed air injected from the compressed air supply nozzle 13 disappears, so that the butterfly valve 11 is opened (original position) as shown in FIG. Is returned to.

  In other words, in the present embodiment, for example, the rotating shaft 12 is disposed offset from the center line, so that when the compressed air is not supplied from the compressed air supply nozzle 13, the upstream of the butterfly valve 11. A moment difference is generated around the rotating shaft 12 due to the pressure difference between and downstream, and the valve is automatically returned to the valve open position (original position) shown in FIGS. 2 and 4 and held at the valve open position.

  By the way, depending on the case, the offset of the rotating shaft 12 can be omitted, and a configuration in which a return spring or the like is provided to bias the valve opening direction can also be adopted.

  Thus, according to the present embodiment, the butterfly valve 11 can be opened and closed using the compressed air injected from the compressed air supply nozzle 13, so that the conventional butterfly valve can be opened and closed. Since an expensive electric actuator can be dispensed with, the configuration can be simplified and the cost can be reduced.

  The injection opening surface 13A of the compressed air supply nozzle 13 faces the upstream side in the intake air flow direction, as in the present embodiment shown in FIGS. Can be adjusted to not.

  With such a configuration, compared with the case where the opening surface 13A of the compressed air supply nozzle 13 is arranged so as to face the upstream side in the flow direction of the intake air without such adjustment, the intake air is compressed air. Since it is possible to suppress an increase in the ventilation resistance of the intake passage 4 by flowing into the supply nozzle 13, the performance of the internal combustion engine 1 can be maintained high even if the compressed air supply nozzle 13 is provided in the intake passage 4. it can.

  In the second embodiment, when applied to an internal combustion engine in which an EGR (Exhaust Gas Recirculation) system is employed, contamination / corrosion of the bearing portion of the rotary shaft 12 of the butterfly valve 11 by EGR gas (exhaust component), etc. In order to suppress the adverse effects of the above, a configuration as shown in FIG. 5 is adopted.

That is, the second embodiment has the same configuration as the first embodiment and, as shown in FIG. 5, the compressed air stored in the pressure accumulating tank 5 is transferred to the bearing portion of the rotating shaft 12 of the butterfly valve 11. A configuration for supplying the air through a supply passage 14 connected to the compressed air supply nozzle 13 and cleaning the bearing portion is provided.
A part or all of the compressed air provided for cleaning is guided to the combustion chamber of the internal combustion engine 1.

  With this configuration, it is possible to achieve the same effects as those of the first embodiment while further improving the durability and reliability.

  In the third embodiment, the butterfly valve 11 described in the first embodiment is modified as described later.

  That is, in the third embodiment, as shown in FIG. 6, the butterfly valve 11 is sequentially attached in the valve closing direction by receiving the compressed air injected from the compressed air supply nozzle 13 around the rotating shaft 12 of the butterfly valve 11. A plurality of wings 15 are attached.

  More specifically, the distance between the tip of the compressed air supply nozzle 13 and the compressed air receiving portion of the butterfly valve 11 increases as the degree of closing of the butterfly valve 11 increases. It is assumed that the urging force directly in the valve closing direction to the butterfly valve 11 by the injection pressure of the injected compressed air may be weakened more than a predetermined value depending on the size of each part, the compressed air pressure, and the like.

  In such a case, the compressed air injected from the compressed air supply nozzle 13 can appropriately urge the butterfly valve 11 in the valve closing direction until the butterfly valve 11 is closed to a predetermined value. Is needed.

  For this reason, in the third embodiment, as shown in FIG. 6, the plurality of blades 15 that receive the compressed air injected from the compressed air supply nozzle 13 and urge the butterfly valve 11 in the valve closing direction are replaced with the butterfly valve 11. The rotation shaft 12 is arranged at predetermined angles.

  With such a configuration, when the degree of closing of the butterfly valve 11 is advanced and the direct closing force of the compressed air injected from the compressed air supply nozzle 13 to the butterfly valve 11 is reduced, the injection from the compressed air supply nozzle 13 is performed. The compressed air is urged in the valve closing direction with respect to the blade 15A that comes next to the path of the compressed air, and the degree of closing of the butterfly valve 11 is further advanced, and the valve closing to the blade 15A is performed. When the urging force becomes small, the operation of urging the compressed air in the valve closing direction is sequentially repeated with respect to the blade 15B that arrives in the path of the compressed air next (FIGS. 6 and 7). reference).

  In this embodiment, the blades 15A to 15C are provided, and as shown in FIG. 7, the butterfly valve 11 is completely closed and maintained in the closed state by the action of compressed air on the blades 15C. It has become so.

  However, the number of blades 15 is not limited, and may be changed as appropriate according to specifications such as the size of each part and compressed air pressure.

  As in the first embodiment, when the operating state changes and the on-off valve 5B is closed according to the control signal from the ECU, the butterfly valve 11 is closed by the compressed air injected from the compressed air supply nozzle 13. Since the urging in the valve direction disappears, the butterfly valve 11 is returned to the valve opening position (original position) as shown in FIG.

  That is, also in the third embodiment, as shown in FIG. 8, the rotation shaft 12 is arranged to be offset below the center line, so that compressed air is not supplied from the compressed air supply nozzle 13. A moment difference occurs around the rotary shaft 12 due to the pressure difference between the upstream and downstream of the butterfly valve 11, and the valve is automatically returned to the valve open position (original position) in FIG. 8 and held at the valve open position. become.

  Note that the opening surface 13A of the compressed air supply nozzle 13 does not face the upstream side in the intake air flow direction, as in the first embodiment shown in FIGS. Can be adjusted to.

  However, in the third embodiment, the blade 15 is present, and this blade 15 contributes to suppressing the intake air from flowing into the compressed air supply nozzle 13 and increasing the ventilation resistance of the intake passage 4. Therefore, even if the opening surface 13A of the compressed air supply nozzle 13 is adjusted so as to face the upstream side in the flow direction of the intake air as shown in FIGS. 6 to 8, the performance of the internal combustion engine 1 can be maintained high. It is something that can be done.

  In the fourth embodiment, as described in the first to third embodiments, the butterfly valve 11 is driven to open and close by causing the compressed air injected and supplied from the compressed air supply nozzle 13 to directly collide with the butterfly valve 11 or the like. Instead of the system, the butterfly valve 11 is driven to open and close using an air cylinder 16.

  That is, in the fourth embodiment, as shown in FIG. 9, as in the first embodiment, the butterfly valve 11 is provided, and the compressed air supply nozzle 13 for injecting and supplying the compressed air to the intake passage 4 is It protrudes from the inner wall of the passage 4.

  In the fourth embodiment, the opening / closing drive of the butterfly valve 11 is performed via the air cylinder 16 as shown in FIG.

  The air cylinder 16 is supplied with compressed air stored in the pressure accumulation tank 5 as compressed air for driving the air cylinder 16 through a supply passage 18 connected to the compressed air supply nozzle 13. It has become.

  Therefore, in the fourth embodiment, when the opening / closing valve 5B is controlled to be opened / closed by the ECU according to the operating state, the supply / stop of compressed air to the air cylinder 16 is performed accordingly, and the link mechanism 17 is operated. Accordingly, the butterfly valve 11 is driven to open and close.

  Specifically, when supplying compressed air to the internal combustion engine 1, the butterfly valve 11 is closed via the air cylinder 16 and the compressed air is supplied from the compressed air supply nozzle 13 to the intake passage 4 of the internal combustion engine 1. When supplied and compressed air is not supplied to the internal combustion engine 1, the butterfly valve 11 is opened via the air cylinder 16 and the supply of compressed air from the compressed air supply nozzle 13 is stopped. Yes.

  Even with the configuration of the fourth embodiment, since an expensive electric actuator for opening and closing the butterfly valve as in the prior art can be eliminated, the configuration can be simplified and the cost can be reduced.

  In addition, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Exhaust passage 4 Intake passage 5 Accumulation tank 5A Compressed air supply passage 10 Compressed air introduction part 11 Butterfly valve 13 Compressed air supply nozzle (compressed air supply part)
15 Plural wings 15A to 15C Wings 16 Air cylinder

Claims (4)

A compressed air supply device that supplies compressed air stored in an accumulator tank to an intake passage of an internal combustion engine in a predetermined operation state,
A shut-off valve interposed in the intake passage on the upstream side of the intake air from the compressed air supply portion that faces the intake passage, and when the compressed air is supplied to the intake passage, While configured to shut off the intake upstream side of the shutoff valve and the combustion chamber side of the internal combustion engine,
While using the high pressure of compressed air as a drive source for the opening and closing operation of the shut-off valve ,
A compressed air supply apparatus for an internal combustion engine, wherein the shut-off valve is a butterfly valve, and the butterfly valve is opened and closed by an injection pressure when compressed air is injected toward the butterfly valve . The rotation axis of the butterfly valve is offset with respect to the center of the intake passage so that the butterfly valve rotates in the direction of the original position when injection of compressed air is stopped. Item 2. A compressed air supply device for an internal combustion engine according to Item 1 . The compressed air supply device for an internal combustion engine according to claim 1 or 2 , wherein an injection opening surface of an injection nozzle for compressed air is adjusted so as not to face an upstream side in a flow direction of intake air. A rotation shaft around the butterfly valve, the butterfly valve separately from the, claims 1 to 3, characterized in that at least one wing is arranged acted upon by the injection pressure of the injected compressed air A compressed air supply device for an internal combustion engine according to any one of the above.

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