JP2019120244A - Supercharging support device - Google Patents

Abstract

To improve convenience while improving supercharging efficiency of a supercharger with a simple structure, regarding a supercharging support device.SOLUTION: Compressed air is generated by a compressor 33 driven by an engine 10 and stored in a tank 2. Two inflow passages 4, 5 for supplementing compressed air are connected to the tank 2. The first inflow passage 4 connects between the compressor 33 and the tank 2. The second inflow passage 5 is formed by branching from the first inflow passage 4, and stores compressed air supplied from the outside of a vehicle to the tank 2. An auxiliary turbine 3 coaxial with a compressor 14 of a supercharger 13 is arranged on the outside of an exhaust passage 12, and the auxiliary turbine 3 is rotationally driven by the compressed air stored in the tank 2. An outflow passage 6 connects between the tank 2 and the upstream side of the auxiliary turbine 3. In the outflow passage 6, a valve 7 is interposed for controlling a flow rate of the compressed air supplied to the upstream side of the auxiliary turbine 3. When the supercharger 13 is actuating, the flow rate of the compressed air passing the valve 7 is controlled by a control device 8.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a supercharge assisting device for supporting supercharging operation of a supercharger of an engine (internal combustion engine) mounted on a vehicle.

  Conventionally, in a vehicle equipped with a supercharger-equipped engine, a technology is known that compensates for a response delay or insufficient supercharging of exhaust pressure by supplying compressed air other than exhaust (exhaust gas) upstream of the exhaust turbine. There is. Compressed air is generated by, for example, an engine-driven air compressor or an air pump. It has also been proposed that a second compressor separate from the compressor connected to the exhaust turbine be disposed in the intake passage, and the air motor connected to the second compressor be rotationally driven by compressed air. By assisting the supercharging using compressed air, the rise of the supercharging pressure can be improved (see Patent Documents 1 and 2).

JP, 2017-133436, A JP, 2016-188607, A

  In the configuration in which compressed air is supplied into the exhaust passage, the pressure in the exhaust passage is increased, and the pressure loss is increased. As a result, the exhaust of the engine becomes difficult to flow, which may cause an increase in engine temperature and instability of the combustion state. On the other hand, when the method of rotationally driving the air motor with compressed air is adopted, supercharging can be assisted without increasing the exhaust pressure loss. However, it is necessary to newly install an air motor, which tends to complicate the apparatus configuration and cost.

  Moreover, a supercharger is known as a kind of supercharger which does not have a turbine in an exhaust passage. A normal supercharger is configured to supercharge by rotationally driving a compressor using a driving force of an engine, and mechanical resistance for supercharging operation tends to directly lead to deterioration of fuel consumption. On the other hand, if the compressor is rotationally driven by compressed air, supercharging can be performed without increasing the exhaust pressure loss described above. However, when the means for supplying compressed air is only an engine-driven compressor, the remaining amount of compressed air tends to be insufficient, the convenience is reduced, and the fuel consumption may be significantly reduced due to the driving of the compressor. Therefore, it is desirable to prepare other means different from an engine drive compressor as a means for supplying compressed air.

  One of the objects of the present invention was devised in view of the above problems, and a supercharge supporting device capable of improving the convenience while improving the supercharging efficiency of the supercharger with a simple configuration. To provide. The present invention is not limited to this object, and it is an operation and effect derived from each configuration shown in the “embodiments to be described later”, and it is also possible to exert an operation and effect that can not be obtained by the prior art. It can be positioned as a goal.

  (1) The disclosed supercharging support device is a supercharging support device that supports the supercharging operation of a supercharger of an engine mounted on a vehicle. The apparatus includes at least a compressor driven by the engine to generate compressed air, and a tank storing the compressed air. A first inflow path connecting the compressor and the tank, and a second inflow path branched from the first inflow path to store the compressed air supplied from the outside of the vehicle in the tank Prepare. An auxiliary turbine disposed coaxially with the compressor of the supercharger and disposed outside the exhaust passage of the engine and rotationally driven by the supply of the compressed air stored in the tank, the tank, and the upstream of the auxiliary turbine And an outlet connected to the side. A valve interposed in the outlet path for changing the flow rate of the compressed air supplied upstream of the auxiliary turbine, and a control device for controlling the flow rate of the compressed air passing through the valve when the supercharger is operated And

  The above-mentioned turbocharger includes a turbocharger and a supercharger. The turbocharger is, for example, a supercharger that performs supercharging by rotating the compressor by rotating a turbine interposed on an exhaust passage at an exhaust pressure. Moreover, a supercharger is a supercharger which performs supercharging, for example, rotating the said compressor using the driving force of the said engine (or rotating an electric compressor with battery electric power).

(2) A pressure sensor for detecting a tank pressure, which is a pressure of the compressed air stored in the tank, and a supercharge assistance operated by an occupant of the vehicle to select necessity of support of the supercharging operation It is preferable to provide a switch. Further, it is preferable that the control device controls the flow rate based on the tank pressure and the operation state of the supercharging auxiliary switch.
(3) It is preferable to connect the downstream side of the auxiliary turbine and the intake passage of the engine, and to provide a reuse passage for supplying compressed air after rotationally driving the auxiliary turbine to the intake passage.

(4) It is preferable that the said tank is formed in the shape which penetrated the intake passage of the said engine.
(5) It is preferable that the part located in the said tank side rather than the said valve among the said outflow paths is formed in the shape wound along the outer surface of the intake passage of the said engine.
(6) Preferably, the compressor is integrally formed with an air conditioner compressor mounted on the vehicle.
(7) It is preferable that the supercharger includes a turbine coaxial with the compressor and the auxiliary turbine and disposed inside the exhaust passage.

  By arranging the auxiliary turbine coaxially with the compressor of the turbocharger and arranging it on the outside of the exhaust passage, it is possible to support supercharging with compressed air without increasing exhaust pressure loss with a simple configuration. The supercharging efficiency of the feeder can be improved. In addition, by connecting the first inflow passage and the second inflow passage to the tank of compressed air supplied to the auxiliary turbine, not only the replenishment by the compressor but also the replenishment from the outside of the vehicle can be performed, and the convenience is improved. Can.

It is a schematic diagram which illustrates the composition of the supercharge support device of this embodiment. It is a side view of the vehicle by which the supercharging assistance device was carried. It is a flowchart for demonstrating the control content of a supercharging assistance apparatus. It is a schematic diagram which shows the structure of the supercharging assistance apparatus as a modification. It is a schematic diagram which shows the structure of the supercharging assistance apparatus as a modification.

  Hereinafter, a supercharge assisting device as an embodiment will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude the application of various modifications and techniques that are not specified in the following embodiments. Each structure of this embodiment can be variously modified and implemented in the range which does not deviate from those meaning. Also, they can be selected as needed or can be combined as appropriate.

[1. Device configuration]
FIG. 1 illustrates the configuration of an engine 10 to which the supercharging assistance device according to the embodiment is applied. The engine 10 is provided with a supercharger 13 (turbocharger) that performs supercharging using exhaust gas. The turbocharger 13 is provided with a compressor 14 interposed on the intake passage 11 and a turbine 15 interposed on the exhaust passage 12. An intercooler 16 and a throttle valve 17 are provided in the intake passage 11 downstream of the compressor 14 (closer to the engine 10). The intercooler 16 is a heat exchanger for cooling the intake air introduced into the cylinder of the engine 10, and the throttle valve 17 is a flow control valve for adjusting the amount of intake air.

  The intake passage 11 is provided with an auxiliary turbine 3 having at least a common rotation axis with the compressor 14. The auxiliary turbine 3 is an impeller for supporting the supercharging operation of the turbocharger 13 and is disposed coaxially with at least the compressor 14. In the present embodiment, the three components of the compressor 14, the turbine 15, and the auxiliary turbine 3 are coaxially arranged. The auxiliary turbine 3 is disposed at least outside of the exhaust passage 12, and preferably additionally to the outside of the intake passage 11. The auxiliary turbine 3 may be disposed inside the intake passage 11.

  The engine 10 is provided with a compressor unit 30 that operates using a part of the driving force of the engine 10. An air conditioner compressor 31, a clutch 32, and a compressor 1 are built in the compressor unit 30. The air conditioner compressor 31 is a device that compresses (pressurizes) the refrigerant of the air conditioner mounted on the vehicle 20. The driving force of the engine 10 is input to the air conditioner compressor 31 from the crank pulley of the engine 10 via a power transmission belt.

  On the other hand, the compressor 1 is a compression device having a common rotation axis with the air conditioner compressor 31 and has a function of generating compressed air supplied upstream of the auxiliary turbine 3. The compressor 1 is integrally formed with the air conditioner compressor 31 and provided in the same casing. Further, the clutch 32 is interposed on a power transmission path between the air conditioner compressor 31 and the compressor 1. By engaging the frictional engagement element of the clutch 32, the driving force of the engine 10 input to the air conditioner compressor 31 is also transmitted to the compressor 1, and compressed air is generated. Further, when the frictional engagement element of the clutch 32 is released, the driving force of the engine 10 is not transmitted to the compressor 1.

  On the opposite side of the clutch 32 across the compressor 1, a motor 33 is provided for driving the compressor 1 with the clutch 32 released. The motor 33 is an electric motor for rotating and driving the compressor 1 by consuming the power of the in-vehicle battery. The starter or alternator of the engine 10 may function as the motor 33 described above. In this case, a second clutch may be interposed between the motor 33 and the engine 10, and a third clutch may be interposed between the motor 33 and the compressor 1. By controlling the connection / disconnection state of each clutch, the compressor 1 can be driven by the motor 33 at any timing.

  The compressed air generated by the compressor 1 is stored in a tank 2 which is a pressure vessel. The tank 2 is preferably disposed at a position in contact with the outer surface of the intake passage 11, and more preferably formed in a shape surrounding the periphery of the intake passage 11. As shown in FIG. 1, the tank 2 of the present embodiment is formed in a shape in which the intake passage 11 is inserted. The intake passage 11 is provided axially along the cylinder axis so as to penetrate the center of the cylindrical tank 2.

  The compressor 1 and the tank 2 are connected by a first inflow passage 4 in which a first check valve 18 is interposed. The first check valve 18 is a check valve having a structure that allows the flow of compressed air from the compressor 1 to the tank 2 and prevents the flow of compressed air in the reverse direction. The shape of the flow path of the first inflow path 4 is formed in a serpentine shape so as to increase the contact area with the outside air. As a result, the compressed air is cooled by the outside air and stored in the tank 2 so that the excessive temperature rise of the tank 2 is suppressed.

  Further, a second inflow passage 5 is branched at a position closer to the tank 2 than the first check valve 18. The second inflow path 5 is a passage for storing compressed air supplied from the outside of the vehicle 20 in the tank 2. A compressed air replenishment port 9 (valve) is provided at the end of the second inflow path 5, and a second check valve 19 is interposed in the middle of the second inflow path 5. As shown in FIG. 2, the refilling port 9 is provided inside the lid 35 of the vehicle 20 and adjacent to the fueling port 36. The shape of the replenishment port 9 is the same as that of the air valve of the tire. As a result, the occupant of the vehicle 20 refills the tank 2 with compressed air using an external refilling device 37 such as an air carry or a tire pressure pump installed in, for example, a gas station, a car parts store, or an automobile maintenance factory. It becomes possible.

  As shown in FIG. 1, an outlet 6 connecting the tank 2 and the upstream side of the auxiliary turbine 3 is provided. Further, a valve 7 for changing the flow rate of the compressed air supplied to the upstream side of the auxiliary turbine 3 is interposed in the outflow passage 6. A portion of the outflow passage 6 located closer to the tank 2 than the valve 7 is formed in a shape wound along the outer surface of the intake passage 11. As a result, it becomes possible to cool the entire intake passage 11 by utilizing the temperature decrease due to the opening of the valve 7, and the supercharging efficiency is improved. The opening degree of the valve 7 is controlled by the controller 8. The compressed air supplied from the outflow passage 6 is introduced into the intake passage 11 after the auxiliary turbine 3 is rotated, and reused as supercharged air introduced into the combustion chamber of the engine 10.

  As shown in FIG. 1, the reuse passage 26, which is a flow passage of compressed air introduced from the auxiliary turbine 3 to the intake passage 11, is connected upstream of the compressor 14 of the intake passage 11. This is because the temperature of the compressed air is lowered by expansion and acts to lower the intake air temperature and the temperature of the compressor 14. Thus, by supplying the compressed air used to rotate the auxiliary turbine 3 to the upstream side of the compressor 14, the supercharging efficiency is further improved.

  The control device 8 is an electronic control device (computer) that controls the flow rate of the compressed air passing through the valve 7 when the supercharger 13 operates. The control device 8 incorporates a processor (central processing unit), a memory (main memory), a storage device (storage), an interface device, etc., and is mutually connected via an internal bus. As shown in FIG. 1, a pressure sensor 21, a supercharge auxiliary switch 22, an accelerator opening sensor 23, a vehicle speed sensor 24, and an engine speed sensor 25 are connected to the input side of the control device 8, and the valve 7 is connected to the output side. Is connected.

  The pressure sensor 21 is a sensor that detects the tank pressure, which is the pressure of the compressed air stored in the tank 2. The supercharging assistance switch 22 is an on / off switch operated by the occupant of the vehicle 20, and the necessity of the support of the supercharging operation is selected according to the intention of the occupant. The accelerator opening degree sensor 23 is a sensor for detecting the depression amount of the accelerator pedal (accelerator opening degree), and the vehicle speed sensor 24 is a sensor for detecting a vehicle speed (traveling speed of the vehicle 20). Further, the engine speed sensor 25 is a sensor that detects the rotational speed of the engine 10 (rotation speed per unit time).

The control device 8 opens the valve 7 when the following conditions are satisfied, and implements supercharging assistance using compressed air.
Condition 1. Condition for satisfaction of supercharging implementation condition 2. The supercharging auxiliary switch 22 is on Condition 3. An operating condition in which the exhaust flow rate tends to be insufficient Condition 4. Tank pressure is above the specified pressure

  The condition 1 for performing supercharging is a condition for determining whether the actual supercharging pressure is insufficient with respect to the target supercharging pressure. The target boost pressure is set based on the traveling state of the vehicle 20 (vehicle speed, engine speed, etc.), accelerator opening, engine load, and the like. The actual supercharging pressure is grasped based on, for example, detection information of an intake pressure sensor (not shown) installed in the intake passage 11, the operating state of the engine 10, and the like. Condition 2 is a condition for confirming that the passenger permits the support of the supercharging operation.

  Condition 3 is a condition for determining whether or not the vehicle is in an operating state where the exhaust pressure is low and a high target boost pressure is set, as in the case of a sudden start of the vehicle 20, for example. This condition is determined based on the traveling state of the vehicle 20 (vehicle speed, engine speed, etc.), accelerator opening degree, engine load, and the like. Condition 4 is a condition for confirming that a sufficient flow rate of compressed air can be supplied when the valve 7 is opened. When these conditions are satisfied, the controller 8 calculates the target flow rate of the compressed air based on the difference between the target boost pressure and the actual boost pressure, and controls the opening degree of the valve 7 according to the target flow rate.

  FIG. 3 is a flowchart example for explaining a control method of the valve 7 by the control device 8. First, detection information such as the pressure sensor 21, the supercharging auxiliary switch 22, the accelerator opening sensor 23, the vehicle speed sensor 24, and the engine speed sensor 25 is input to the control device 8 (step A 1). Subsequently, it is determined whether condition 1 (supercharge implementation condition) is satisfied (step A2). If Condition 1 is not satisfied, supercharging is unnecessary, and supercharging assist is also unnecessary, and this flow is ended.

  When the condition 1 is satisfied, the condition 2 (the supercharge auxiliary switch 22 is on, step A3), the condition 3 (the operation state in which the exhaust flow rate tends to be insufficient, step A4), the condition 4 (the tank pressure is It is determined that the pressure is equal to or higher than a predetermined pressure, and the success or failure of step A5). Here, if all of the conditions 2 to 4 hold, the target flow rate of compressed air is calculated based on the difference between the target boost pressure and the actual boost pressure (step A6), and the valve is adjusted according to the target flow rate. The opening degree 7 is controlled (step A7). On the other hand, if any one of the conditions 2 to 4 is not satisfied, the supercharging assistance by the compressed air is not performed, and the normal supercharging control is performed (step A8).

[2. Action, effect]
(1) In the above-described supercharge assisting device, the auxiliary turbine 3 is disposed coaxially with the compressor 14 and the turbine 15 of the supercharger 13 and outside the exhaust passage 12. With such a simple configuration, supercharging assistance with compressed air can be performed without increasing exhaust pressure loss of the engine 10, and the supercharging efficiency of the turbocharger 13 can be improved. For example, the actual boost pressure can be made to approach the target boost pressure quickly in an operating condition where exhaust pressure is low and a high target boost pressure is set, such as when the vehicle 20 is suddenly started. Acceleration performance can be improved.

  Further, the supercharging support device described above is provided with the second inflow path 5 for introducing the compressed air supplied from the outside of the vehicle 20 into the tank 2. Thus, not only the compressed air generated by the compressor 1 but also the compressed air replenished from the outside of the vehicle 20 can be used in combination to rotationally drive the auxiliary turbine 3. For example, when the remaining amount of compressed air decreases, it is possible for the occupant to stop at the gas station to refill the tank 2 with compressed air. Therefore, the compressed air in the tank 2 can be secured without frequently operating the engine 10, and supercharging support can be performed anytime, and convenience can be improved.

  (2) In the above-described supercharging support device, as described in the conditions 2 and 3, the flow rate of the compressed air is controlled based on not only the tank pressure but also the operating state of the supercharging auxiliary switch. As described above, the convenience can be improved by confirming the intention of the occupant when determining the implementation of the supercharging assist. For example, compressed air can be preserved under the situation where the occupant determines that supercharging support is unnecessary. On the other hand, the supercharging support can be started at any time when the passenger desires supercharging support.

  (3) In the above-described supercharging support device, as shown in FIG. 1, the reuse passage 26 connecting the downstream side of the auxiliary turbine 3 and the intake passage 11 is formed. The compressed air after rotationally driving the auxiliary turbine 3 is introduced into the intake passage 11 through the reuse passage 26. Thereby, the intake air temperature can be reduced by utilizing the temperature reduction of the expanded compressed air. Further, since the connection position of the reuse passage 26 to the intake passage 11 is on the upstream side of the compressor 14, not only the intake air but also the compressor 14 can be cooled. Therefore, the supercharging efficiency can be further improved.

  (4) In the supercharging support device described above, the tank 2 is formed in a shape in which the intake passage 11 is inserted. As shown in FIG. 1, the intake passage 11 is provided axially along the cylinder axis so as to penetrate the center of the cylindrical tank 2. As described above, by making the intake passage 11 penetrate the tank 2, it is possible to cool the supercharged air by utilizing the temperature drop accompanying the pressure drop of the tank 2, and it is possible to improve the supercharging efficiency.

  (5) In the above-described supercharging support device, the outflow passage 6 is formed in a shape wound along the outer surface of the intake passage 11. As shown in FIG. 1, a portion of the outflow passage 6 located closer to the tank 2 than the valve 7 is wound around the intake passage 11. With such a structure, it is possible to cool the supercharged air by utilizing the temperature drop associated with the pressure drop of the outlet channel 6, and it is possible to further improve the supercharging efficiency.

  (6) In the above-described supercharging support device, the compressor 1 is provided in the same casing as the air conditioner compressor 31, that is, integrally formed with the air conditioner compressor 31. Thus, by unifying the compressor 1 and the air-conditioner compressor 31, a mechanism for generating compressed air for supercharging assist without appreciably changing the number and layout of existing belt drive accessories is unreasonable. It can be incorporated and improve the adaptability to the existing supercharging system.

  (7) In the above-described supercharging support device, the compressor 14 of the supercharger 13 (turbocharger) that performs supercharging using exhaust gas is energized by the auxiliary turbine 3. As a result, compared with a supercharging support system in which the turbine 15 is rotationally driven by, for example, compressed air, there is no risk of increasing exhaust pressure loss, and engine temperature rise and combustion state instability are more reliably prevented. can do.

[3. Modified example]
In the above-mentioned embodiment, although supercharging support of supercharger 13 provided with turbine 15 on exhaust passage 12 was explained in full detail, the concrete shape and supercharging method of supercharger 13 are not limited to this. For example, as shown in FIG. 4, the auxiliary turbine 3 may be configured to perform rotation assistance of the compressor 14 with respect to the turbocharger 13 having no turbine 15 on the exhaust passage 12. That is, it is also possible to extract the structure regarding the auxiliary turbine 3 and the tank 2 among the structures of the above-mentioned embodiment, and to apply to the engine 10 which mounts a supercharger.

  Further, as shown in FIG. 4, a bypass passage 27 may be provided to bypass the compressor 14. The bypass passage 27 is formed to connect the upstream side and the downstream side of the compressor 14 in the intake passage 11. This makes it possible to secure a flow passage for natural intake. A switching valve or a flow control valve may be disposed in the vicinity of a branch point between the intake passage 11 and the bypass passage 27 to adjust the magnitude of the intake pressure loss, the intake flow rate, the supercharging amount, and the like.

  Moreover, in the above-mentioned embodiment, although the recycle passage 26 was illustrated as the structure connected to the intake passage 11, the recycle passage 26 may be omitted. For example, as shown in FIG. 5, the auxiliary turbine 3 may be disposed at a position which is not included in either the intake passage 11 or the exhaust passage 12. By at least making the auxiliary turbine 3 coaxial with the compressor 14 and arranging the same on the outside of the exhaust passage 12, an adverse effect on exhaust pressure loss can be prevented, and a structure having the same effect as the above-described embodiment is obtained. . Note that only the above-mentioned condition 1 is a condition essential to the implementation of the supercharging assist for achieving the same effect as that of the above-described embodiment. Conditions 2-4 are only additional conditions added as needed.

Reference Signs List 1 compressor 2 tank 3 auxiliary turbine 4 first inflow passage 5 second inflow passage 6 outflow passage 7 valve 8 control device 9 replenishment port 10 engine 11 intake passage 12 exhaust passage 13 supercharger 14 compressor 15 turbine 26 reuse passage

Claims (7)

A supercharging support device for supporting supercharging operation of a supercharger of an engine mounted on a vehicle, comprising:
A compressor driven by at least the engine to generate compressed air;
A tank for storing the compressed air;
A first inflow path connecting the compressor and the tank;
A second inflow path branched from the first inflow path to store the compressed air supplied from the outside of the vehicle in the tank;
An auxiliary turbine disposed coaxially with the compressor of the supercharger and disposed outside the exhaust passage of the engine, and rotationally driven by receiving the supply of the compressed air stored in the tank;
An outlet connecting the tank and the upstream side of the auxiliary turbine;
A valve interposed in the outflow path for changing the flow rate of the compressed air supplied upstream of the auxiliary turbine;
A control device for controlling a flow rate of the compressed air passing through the valve when the supercharger is operated;
A supercharging support device characterized by comprising. A pressure sensor for detecting a tank pressure which is a pressure of the compressed air stored in the tank;
And a supercharge assist switch operated by an occupant of the vehicle to select whether or not to support the supercharge operation.
The supercharging assistance device according to claim 1, wherein the control device controls the flow rate based on the tank pressure and the operation state of the supercharging auxiliary switch. 2. The apparatus according to claim 1, further comprising a recycle passage connecting a downstream side of the auxiliary turbine and an intake passage of the engine and supplying compressed air after rotationally driving the auxiliary turbine to the intake passage. The supercharging support device according to 2). The supercharging assistance device according to any one of claims 1 to 3, wherein the tank is formed in a shape in which an intake passage of the engine is inserted. The region of the outflow passage located closer to the tank than the valve is formed in a shape wound along the outer surface of the intake passage of the engine. The supercharging assistance device according to any one of the above. The supercharging assistance device according to any one of claims 1 to 5, wherein the compressor is integrally formed with an air conditioner compressor mounted on the vehicle. The supercharger according to any one of claims 1 to 6, wherein the supercharger has a turbine coaxially disposed with the compressor and the auxiliary turbine and disposed in the exhaust passage. .

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