Charge air cooling system and charge air cooler for the same

A charge air cooler cools charge air compressed with a compressor. The charge air cooler includes a shell and an inner tube, which is accommodated in the shell and exposed to an interior of the shell. The shell has an inlet and an inlet to enable charge air to flow through the inlet, the interior of the shell, and the inlet and to pass around the inner tube in the shell. The inner tube is configured to draw working fluid from a transmission device of the vehicle or an engine and to conduct heat exchange between charge air, which flows through the interior of the shell, and working fluid to warm working fluid.

TECHNICAL FIELD

The present disclosure relates to a charge air cooling system for a vehicle. The present disclosure further relates to a charge air cooler for the charge air cooling system.

BACKGROUND

A known vehicle may be equipped with a transmission device coupled with a crankshaft of an engine to transmit output power of the engine. Such a transmission device, in general, includes a gear mechanism to reduce rotation speed of the crankshaft at a predetermined gear ratio and to manipulate output torque of the transmission. The transmission device contains working fluid such as lubricant fluid and/or torque converter fluid. For example, in a cold climate, such working fluid in the transmission device may be cold and may have high viscosity. It may be desirable to warm up working fluid in the transmission device quickly to reduce viscosity of working fluid immediately after ignition of an engine of a vehicle. In addition, it may be also desirable to warm up working fluid in the engine quickly immediately after ignition of the engine.

SUMMARY

The present disclosure addresses the above-described concerns.

According to an aspect of the preset disclosure, a charge air cooler is for cooling charge air, which is compressed with a compressor. The charge air cooler comprises a shell. The charge air cooling system further comprises an inner tube accommodated in the shell and exposed to an interior of the shell. The shell has an inlet and an outlet to enable charge air to flow through the inlet, the interior of the shell, and the outlet and to pass around the inner tube in the shell. The inner tube is configured to draw working fluid from a transmission device of the vehicle or working fluid from an engine and to conduct heat exchange between charge air, which flows through the interior of the shell, and working fluid.

According to another aspect of the preset disclosure, a charge air cooling system is for an engine of a vehicle. The charge air cooling system comprises a compressor to compress intake air to produce charge air. The charge air cooling system further comprises a charge air cooler configured to receive charge air from the compressor. The charge air cooling system further comprises a transmission device for manipulating output power of the engine. In a starting state after ignition of the engine, the charge air cooler is configured to receive working fluid from the transmission device or working fluid from the engine and to conduct heat exchange between charge air and working fluid to cool charge air and to warm working fluid.

DETAILED DESCRIPTION

First Embodiment

As follows, a first embodiment of the present disclosure will be described with reference toFIGS. 1 to 4. As shownFIG. 1, an internal combustion engine200has at least one cylinder connected with an intake manifold210and an exhaust manifold220. In the present example, the engine200is a direct injection engine having four cylinders. The engine200is combined with an intake and exhaust system including an intake valve410, an intake passage420, a turbocharger300, and an exhaust passage430. The intake valve410is equipped in the intake passage420. The turbocharger300includes a compressor310and a turbine320, which are rotatably connected with each other concentrically via a common axis. The engine200is connected with the intake passage420via the charge air cooler100and the compressor310. The engine200is further connected with the exhaust passage430via the exhaust manifold220and the turbine320.

The intake passage420conducts intake air through the intake valve410into the compressor310. The intake valve410is equipped in the intake passage420to regulate a quantity of intake air flowing into the compressor310. The compressor310pressurizes the intake air. The charge air cooler100functions as an intercooler to cool the compressed intake air. The engine200draws the cooled intake air. The engine200includes an injector (not shown) to inject fuel into each cylinder to form air-fuel mixture with intake air. The air-fuel mixture is burned in the cylinder to drive a piston in the cylinder. The engine200emits exhaust gas through the exhaust manifold220and the turbine320to the exhaust passage430. The turbine320is driven by the exhaust gas emitted from the engine200to rotate the compressor310thereby to cause the compressor310to compress intake air and to press-feed the compressed intake air through the charge air cooler100into the engine200.

The engine200is equipped with a transmission device10. More specifically, a crankshaft of the engine200may be coupled with an input shaft of the transmission device10. The transmission device10may be an automatic transmission device or a manual transmission device. More specifically, the automatic transmission device may be a torque-converter transmission device or a CVT transmission device. The transmission device10may employ various configurations other than the presently exemplified configurations. The transmission device10may include various gear mechanisms such as a planetary gear mechanism for adjusting, for example, a reduction ratio and a rotation speed of an output shaft, and/or for adjusting, for example, a torque of the output shaft. The transmission device10contains working fluid. The working fluid may be, for example, lubricant, torque converter fluid, and/or thermal medium (warming and/or cooling medium).

The transmission device10is connected with the charge air cooler100, a first radiator (transmission radiator)30, and circulation passages1and3, which are connected with each other via a valve60.

The first radiator30may have a fin and tube configuration to conduct heat exchange between working fluid, which flows through a fluidic passage inside the first radiator30, with air, which passes through air passages formed among fins and tubes of the first radiator30. The first radiator30may be equipped with a first fan37to cause airflow through the air passages thereby to enhance efficiency of heat exchange.

The charge air cooler100is connected with a second radiator (charge air radiator)50and a circulation passage5. The second radiator50may have a fin and tube configuration to conduct heat exchange between working fluid, which flows through a fluidic passage inside the second radiator50, with air, which passes through air passages formed among fins and tubes of the second radiator50. The second radiator50may be equipped with a second fan57to cause airflow through the air passages thereby to enhance efficiency of heat exchange. The working fluid of the second radiator50may be coolant such as cooling water containing anti-freezing solution.

When the compressor310pressurizes intake air, the compressor310substantially causes adiabatic compression in the intake air to increase pressure and temperature of the intake air. The charge air cooler100conducts heat exchange with working fluid to cool the pressurized intake air. In this way, the charge air cooler100increases intake air mass per unit volume to enable to increase a quantity of fuel to be burned with the cooled intake air as mixture. Thus, the charge air cooler100enhances combustion efficiency of mixture of intake air and fuel in the combustion chamber of the engine200.

It is noted that, the engine200discharges exhaust gas immediately after the engine200is started to rotate the turbine320and thereby to drive the compressor310. When the engine200is in a starting state immediately after ignition of the engine200, the compressor310enables to start adiabatic compression instantly in intake air to pressurize the intake air and to increase temperature of the intake air. That is, the charge air cooler100draws high-temperature intake air immediately after starting of the engine200, even in the state where exhaust gas is not necessarily at high temperature.

As shown inFIG. 2, the charge air cooler100may have a shell and tube configuration. Specifically, the charge air cooler100includes an inner tube140, an inner tube146, and a shell120. The shell120includes a tubular body and end caps to form a hollow cavity accommodating the inner tube140and the inner tube146. The inner tube146is located at the downstream side of the inner tube140relative to the flow of charge air.

The inner tubes140and146may employ various forms such as a coil form, a U-shape form, and/or the like. The inner tubes140and146may be equipped with fins for conducting heat effectively with intake air. The shell120is communicated with an inlet102and an inlet104to enable charge air, which is pressurized by the compressor310, therethrough and to conduct heat exchange between the charge air and working fluid flowing through the inner tubes140and146. The inner tubes140and146are exposed directly to the interior of the shell120to enable direct heat exchange with charge air.

The inner tube140is connected with the transmission device10through the circulation passage1and the valve60. The circulation passage1is equipped with a first pump18to feed working fluid from the transmission device10. The inner tube140is further connected with the first radiator30through a part of the circulation passage1, the valve60, and the circulation passage3. The circulation passage3is equipped with a second pump38to feed working fluid from the first radiator30.

The inner tube146is connected with the second radiator50through a circulation passage5. The circulation passage5is equipped with a third pump58to feed working fluid from the second radiator50to the inner tube146. The third pump58may regularly circulate working fluid between the second radiator50and the inner tube146.

The circulation passage1is equipped with a temperature sensor19for detecting temperature of working fluid flowing from the transmission device10. The temperature sensor19is electrically communicated with an ECU (electronic control unit)500to send detection signal to the ECU500.

In the present example, the valve60is a six-way valve. Further, in the present example, the valve60includes four three-way valve elements as shown by circles inFIG. 2. Each of the valve elements includes one inlet and two outlets. The valve element is configured to switch inner passage to communicate the one inlet with one of the two outlets. The valve60is configured to switch circulation of working fluid among the transmission device10, the charge air cooler100, and the first radiator30. The valve60may have a solenoid actuator, which is electrically connected with the ECU500and configured to be manipulated with the ECU500. The valve elements of the valve60may be formed between a tubular body and a shaft, which is movable in the tubular body, to switch communication between passages formed between lands of the shaft and holes and cavities of the tubular body.

As shown inFIG. 3, the circulation passage1includes passages11,13,14,16. The passage11and the passage16connect the transmission device10with the valve60. The passage13and the passage14connect the valve60with the charge air cooler100. The circulation passage3includes passages31and32, which connect the valve60with the first radiator30. The circulation passage5includes passages51and52, which connect the charge air cooler146with the second radiator50.

Subsequently, operation of the power train system when the engine200is in a starting state immediately after ignition of the engine200will be described.

As shown inFIG. 3, in the starting state, the valve60is manipulated to form passages to communicate between the transmission device10and the charge air cooler100. Specifically, the transmission device10is communicated with the charge air cooler100through a circulation passage formed by the passage11, the valve60, and the passage13. In addition, the charge air cooler100is communicated with the transmission device10through a circulation passage formed by the passage14, the valve60, and the passage16. Thus, the first pump18circulates working fluid between the transmission device10and the inner tube140through the passages (circulation passage1), and the valve60. In this way, in the starting state, the charge air cooler100conducts heat exchange between working fluid flowing from the transmission device10and charge air flowing though the charge air cooler100. Therefore, working fluid of the transmission device10is enabled to be warmed up quickly immediately after ignition of the engine. In general, working fluid of the transmission device10has high viscosity under a cold state. Therefore, the present configuration may be effective to reduce viscosity of working fluid of the transmission device10instantly thereby to facilitate smooth operation of the transmission device10quickly.

In the starting state, the valve60communicates the passage31with the passage32. The second pump38circulates working fluid flowing from the first radiator30through the passage31, the valve60, and the passage32. In the present state, the second pump38may circulate working fluid between the first radiator30with an auxiliary thermal source (not shown) to conduct heat exchange between the auxiliary thermal source and air passing through the first radiator30thereby to cool the auxiliary thermal source.

In addition, the third pump58circulates working fluid flowing between the second radiator50and the inner tube146through the passage51and the passage52. In the present state, the third pump58may circulate working fluid between the second radiator50with another auxiliary thermal source (not shown) to conduct heat exchange between the other auxiliary thermal source and air passing through the second radiator50thereby to cool the auxiliary thermal source.

When a sufficient time elapses after ignition of the engine200, working fluid in the transmission device10is sufficiently warmed with charge air flowing through the charge air cooler100. Thus, transition is made from the starting state into a normal state. In the normal state, it is deemed that working fluid of the transmission device10need not be warmed up any longer.

It is noted that, as the transmission device10operates, working fluid in the transmission device10generates heat itself due to, for example, sharing deformation of working fluid with high viscosity and mechanical friction of inner components such as gears. Therefore, in the normal state, working fluid of the transmission device10needs cooling down.

In consideration of the condition, as shown inFIG. 4, in the normal state, the valve60is manipulated to form passages to communicate between the transmission device10and the first radiator30.

Specifically, the transmission device10is communicated with the first radiator30through a circulation passage formed by the passage11, the valve60, and the passage31. In addition, the first radiator30is communicated with the transmission device10through a circulation passage formed by the passage32, the valve60, and the passage16.

As same as the starting state, the inner tube146of the charge air cooler100is regularly communicated with the second radiator50through the circulation passage formed by the passage51and the passage52.

Thus, the first pump18and the second pump38circulate working fluid between the transmission device10and the first radiator30through a part of the circulation passage1, the valve60, and the circulation passage3. In this way, in the normal state, the first radiator30conducts heat exchange between working fluid of the transmission device10and air flowing though the first radiator30. Therefore, working fluid of the transmission device10is enabled to be cooled down in the normal state.

In addition, the third pump58circulates working fluid between the inner tube146of the charge air cooler100and the second radiator50through the circulation passage5. In this way, in the normal state, the second radiator50conducts heat exchange between working fluid of the inner tube146and air flowing though the second radiator50. Therefore, working fluid of the inner tube146is enabled to be cooled down in the normal state.

The ECU500may function as a controller to make determination of the transition from the starting state to the normal state based on, for example, the detection signal of the temperature sensor19, elapsed time after ignition of the engine200in the starting state, and/or the like.

When a predetermined time elapses after stoppage of the engine200, the ECU500may manipulate the valve60to recover the passages in the normal state to the passages in the starting state. The ECU500may function as the controller to make determination to recover the passages based on, for example, the detection signal of the temperature sensor19, elapsed time after stoppage of the engine200, and/or the like.

As described above, the present configuration enables to warm working fluid in the transmission device10with the charge air cooler100, even immediately after starting of the engine200in which temperature of exhaust gas may be deemed to be low and/or unstable. In this way, the present configuration may provide effective thermal source, which is heated immediately after ignition of the engine200and is desirably cooled instantly. Thus, the present configuration may enable smooth start up of the transmission device10and the engine200.

In addition, the inner tube140is exposed to the interior the charge air cooler100, thereby to enable direct heat exchange between working fluid and charge air. The present configuration may further facilitate heat exchange between working fluid with charge air.

Second Embodiment

The second embodiment will be described with reference toFIGS. 6 to 8. As shown inFIG. 6, a charge air cooler2100according to the second embodiment includes a shell2120and an inner tube2140. The inner tube2140is directly exposed to the interior of the shell2120. The shell2120has a hollow cavity accommodating the inner tube2140. The inner tube2140may employ various forms.

The charge air cooler2100is equipped with a downstream cooler2200. The downstream cooler2200employs a fin and tube configuration including multiple fins and multiple tubes, which are stacked alternately to each other. The tubes form passages to pass charge air flowing from the charge air cooler2100toward the engine200. The fins form passages to pass air therethrough to enhance heat exchange between charge air and air passing around the fins.

A transmission device2010is connected with the charge air cooler2100, the first radiator (transmission radiator)30, and circulation passages2001and3, which are connected with each other via a valve2060. In the present second embodiment, the second radiator (charge air radiator)50is omitted. The inner tube2140is connected with the transmission device2010through a circulation passage2001and the valve2060. The circulation passage2001is equipped with the first pump18to feed working fluid from the transmission device2010.

The transmission device2010is equipped with a temperature sensor2019. in the second embodiment, the temperature sensor2019is for detecting temperature of working fluid flowing inside the transmission device2010. The temperature sensor2019may be a thermostat device including a bimetal structure and/or thermal expansion/contraction structure. The temperature sensor2019is coupled with the valve2060via a fluidic and/or mechanical connection2018. The temperature sensor2019is configured to manipulate the valve2060in a mechanical and/or fluidic manner according to temperature of working fluid. The valve2060is a six-way valve, similarly to the first embodiment.

As shown inFIG. 6, the circulation passage2001includes passages2011,2013,2014,2016. The passage2011and the passage2016connect the transmission device2010with the valve2060. The passage2013and the passage2014connect the valve2060with the charge air cooler2100. The circulation passage3includes passages31and32, which connect the valve2060with the first radiator30.

As shown inFIG. 6, in the starting state, the valve2060is manipulated to form passages to communicate between the transmission device2010and the charge air cooler2100. Specifically, the transmission device2010is communicated with the charge air cooler2100through a circulation passage formed by the passage2011, the valve2060, and the passage2013. In addition, the charge air cooler2100is communicated with the transmission device2010through a circulation passage formed by the passage2014, the valve2060, and the passage2016. Thus, the first pump18circulates working fluid between the transmission device2010and the inner tube2140through the passages (circulation passage2001) and the valve2060. In this way, in the starting state, the charge air cooler2100conducts heat exchange between working fluid and charge air. In the starting state, the valve2060communicates the passage31with the passage32.

As shown inFIG. 7, in the normal state, the valve2060is manipulated to form passages to communicate between the transmission device2010and the first radiator30. Specifically, the transmission device2010is communicated with the first radiator30through a circulation passage formed by the passage2011, the valve2060, and the passage31. In addition, the first radiator30is communicated with the transmission device2010through a circulation passage formed by the passage32, the valve2060, and the passage2016. Thus, the first pump18and the second pump38circulate working fluid between the transmission device2010and the first radiator30through a part of the circulation passage2001, the valve2060, and the circulation passage3.

When temperature of working fluid in the transmission device2010decreases sufficiently, the temperature sensor2019may manipulate the valve2060to recover the passages in the normal state to the passages in the starting state.

Third Embodiment

The third embodiment is substantially equivalent to the second embodiment excluding the configuration in the normal state. According to the third embodiment, transition is made from the stating state shown inFIG. 6to the normal state shown inFIG. 8.

As shown inFIG. 8, a valve3060is manipulated to form passages to communicate among the transmission device2010, the charge air cooler2100, and the first radiator30. Specifically, the transmission device2010is communicated with the charge air cooler2100through a circulation passage formed by the passage2011, the valve3060, and the passage2013. The charge air cooler2100is communicated with the first radiator30through a circulation passage formed by the passage2014, the valve3060, and the passage31. The first radiator30is communicated with the transmission device2010through a circulation passage formed by the passage32, the valve3060, and the passage2016. Thus, the first pump18and the second pump38circulate working fluid among the transmission device2010, the charge air cooler2100, and the first radiator30through a part of the circulation passage2001, the valve3060, and the circulation passage3.

Fourth Embodiment

FIG. 9shows a fourth embodiment of the present disclosure. The fourth embodiment is substantially equivalent to the second embodiment and the third embodiment excluding the configuration in which fluid connections of working fluid with the transmission device2010is replaced fluid connections of working fluid with the engine200. The temperature sensor2019detects temperature of working fluid flowing inside the engine200or temperature of working fluid flowing through the circulation passage2001. In addition, the temperature sensor2019manipulates the valve2060(3060) according to temperature of working fluid of the engine200.

The present configuration enables to warm working fluid of the engine200in the stating state, thereby to quickly warm up the engine200. When working fluid of the engine200is sufficiently warmed up, transition is made from the staring state inFIG. 9into the normal mode inFIG. 7or into the normal mode inFIG. 8.

Other Embodiment

The first embodiment may employ the valve3060in the third embodiment. That is, in the first embodiment, working fluid may be circulated among the transmission device10, the inner tube140of the charge air cooler100, and the transmission radiator30in the normal state.

The charge air cooler2100and the downstream cooler2200may be employed in the first embodiment. The charge air cooler100may be employed in the second to fourth embodiments.

The ECU500and the temperature sensor19may be employed in the second to fourth embodiments. The temperature sensor2019may be employed in the first embodiment.

The downstream cooler2200may be located at the upstream of the charge air cooler2100.

The second pump38may be omitted. In this case, working fluid may not be circulated in the first radiator30in the starting state.

The charge air cooler100is not limited to employ a shell and tube configuration as exemplified above. The charge air cooler100may employ various configurations such as a fin and tube configuration and/or a plate and tube configuration.

The first and second valves60and80need not to have the above-exemplified configuration and may employ various configurations.