This application is based on and claims the benefit of Japanese Patent Application No. 2018-040786, filed on Mar. 7, 2018, which is incorporated by reference herein in its entirety.
The present disclosure relates to a hybrid vehicle and more particularly to a hybrid vehicle provided with, as well as a drive motor unit, an internal combustion engine having a decompression device for releasing compression pressure in a cylinder.
An internal combustion engine provided with a decompression device (also called a pressure reducing device) for releasing compression pressure in a cylinder. is known. This kind of decompression device is configured to be able to select between a state in which a decompression operation to release the compression pressure in the cylinder is performed (hereunder, referred to as a “decompression operating state”) and a state in which the decompression operation described above is not performed even if a crankshaft is rotating (hereunder, referred to as a “decompression stop state”).
For example, JP 2014-047695 A discloses a control device for an internal combustion engine that includes the decompression device as described above. In order to reduce vibration of a vehicle body, this control device controls the decompression device such that the decompression operating state in the course of engine stop and in the course of engine start-up is selected. Moreover, an example of this decompression device is a variable valve operating device that can change the closing timing of an intake valve. The decompression operating state is achieved by retarding the closing timing of the intake valve.
There is known a hybrid vehicle provided with a power train that includes an internal combustion engine having a plurality of cylinders and a drive motor unit having an electric motor coupled to the internal combustion engine without a clutch therebetween.
According to this kind of hybrid vehicle, it is effective to install a decompression device in order to reduce vibration and noise associated with resonance of the power train due to compression of the internal combustion engine (i.e. excitation force) in the course of engine stop and the course of engine start-up in which combustion is not performed.
More specifically, if the compression is continuously performed in all the cylinders, the resonance occurs at the power train in an engine speed range (hereunder, referred to as a “first power train resonance range”) that centers on an engine speed value at which the period of excitation due to the compression coincides with a natural vibration period of the drive motor unit. If the decompression device is provided for each of all the cylinders, the resonance can be reduced by the use of the decompression device in this kind of first power train resonance range.
On the other hand, in the hybrid vehicle having the configuration described above, it is conceivable to install the decompression device for only a subset of one or more cylinders (that is, one or more but not all the cylinders of the internal combustion engine) for reducing cost. However, if the number of cylinders having the decompression device is decreased without special consideration with regard to which cylinder the decompression device is installed for, the resonance may not be properly reduced in the first power train resonance range described above.
The present disclosure has been made to address the problem described above, and an object of the present disclosure is to provide a hybrid vehicle that can reduce resonance in a first power train resonance range by the use of a decompression device while reducing cost by decreasing the number of cylinders having the decompression device.
A hybrid vehicle according to the present disclosure includes a power train including an internal combustion engine equipped with a plurality of cylinders and a drive motor unit. The drive motor unit includes an electric motor coupled to the internal combustion engine without a clutch interposed between the drive motor unit and the internal combustion engine. The internal combustion engine includes one or more decompression devices that are each installed for a subset of one or more cylinders that are one or more but not all of the plurality of cylinders, the one or more decompression devices operating to release compression pressure in the subset of one or more cylinders in at least one of a course of an engine stop and course of an engine start-up in which combustion is not performed. The subset of one or more cylinders are selected such that, when the one or more decompression devices are operating, compression is not produced sequentially in cylinders that are adjacent to each other in terms of a firing order of the internal combustion engine.
The hybrid vehicle may further include a control device. In stopping an operation of the one or more decompression devices in the course of the engine start-up, the control device may be configured, when an engine speed is higher than an upper limit value of a first power train resonance range and is lower than a lower limit value of a second power train resonance range located on a higher engine speed side relative to the first power train resonance range, to stop the operation of the one or more decompression devices. The first power train resonance range may be an engine speed range that centers on an engine speed value at which a period of excitation due to compression in the internal combustion engine coincides with a natural vibration period of the motor drive unit when the operation of the one or more decompression devices is stopped. The second power train resonance range may be an engine speed range that centers on an engine speed value at which the period of the excitation coincides with the natural vibration period of the drive motor unit when the one or more decompression device are operating.
The hybrid vehicle may further include a control device. In operating the one or more decompression devices in the course of the engine stop, the control device may be configured, when an engine speed is higher than an upper limit value of a first power train resonance range and is lower than a lower limit value of a second power train resonance range located on a higher engine speed side relative to the first power train resonance range, to operate the one or more decompression devices. The first power train resonance range may be an engine speed range that centers on an engine speed value at which a period of excitation due to compression in the internal combustion engine coincides with a natural vibration period of the motor drive unit when an operation of the one or more decompression devices is stopped. The second power train resonance range may be an engine speed range that centers on an engine speed value at which the period of the excitation coincides with the natural vibration period of the drive motor unit when the one or more decompression device are operating.
According to the hybrid vehicle of the present disclosure, the one or more decompression devices are installed for the subset of one or more cylinders that are selected such that, when the one or more decompression devices are operating, compression is not produced sequentially in cylinders that are adjacent to each other in terms of the firing order. According to the internal combustion engine equipped with the one or more decompression devices installed as just described, when the one or more decompression devices are operating, the value of engine speed at which the period of the excitation due to the compression in the internal combustion engine coincides with the natural vibration period of the motor drive unit can be made higher as compared to when the compression is performed in all the cylinders of the internal combustion engine. Therefore, according to the hybrid vehicle of the present disclosure, resonance in the first power train resonance range can be reduced by the use of the one or more decompression devices similarly to the example in which a decompression device is installed for all the cylinders, while reducing cost by decreasing the number of cylinders having the decompression device.
In the following embodiments of the present disclosure, the same components in the drawings are denoted by the same reference numerals, and redundant descriptions thereof are omitted or simplified. Moreover, it is to be understood that even when the number, quantity, amount, range or other numerical attribute of an element is mentioned in the following description of the embodiments, the present disclosure is not limited to the mentioned numerical attribute unless explicitly described otherwise, or unless the present disclosure is explicitly specified by the numerical attribute theoretically. Furthermore, structures or steps or the like that are described in conjunction with the following embodiments are not necessarily essential to the present disclosure unless explicitly shown otherwise, or unless the present disclosure is explicitly specified by the structures, steps or the like theoretically.
Firstly, a first embodiment according to the present disclosure will be described with reference to
1-1. Example of Configuration of Power Train of Hybrid Vehicle
1-1-1. Internal Combustion Engine (In-Line Four-Cylinder)
As an example, the internal combustion engine 20 is a spark ignition in-line four-cylinder engine and has first to fourth cylinders #1 to #4 in order from its one end in the cylinder row direction. However, an internal combustion engine according to the present disclosure may alternatively be a compression ignition engine, as long as it has a plurality of cylinders.
The internal combustion engine 20 is equipped with fuel injection valves 22 and an ignition device 24 (only spark plugs are illustrated). Each of the fuel injection valves 22 is arranged in a cylinder, and, as an example, injects fuel directly into the cylinder. The ignition device 24 ignites an air-fuel mixture in each cylinder by the use of the spark plug arranged for each cylinder.
The internal combustion engine 20 is further equipped with decompression devices 26. An example of selection of cylinders for which the decompression device 26 is provided will be described later.
To be more specific, each of the HLA holders 38 is fixed to a cylinder head 46, formed into a bottomed cylindrical shape and houses the corresponding HLA 34 such that it can be lifted and lowered. Each of the sliders 40 is driven by the corresponding actuator 44 to reciprocate in the cylinder row direction (i.e., the left-right direction in
Each of the HLAs 34 operates so as to always eliminate a clearance between the intake cam 30 and the rocker arm 32 with its original function (i.e., expansion and contraction motion). On that basis, the position of the slider 40 is adjusted by the use of the actuator 44, and, as a result, the intake valve 28 can be caused to remain open, by the use of the HLA 34, regardless of application of the pressing force of the intake cam 30 to the rocker arm 32. More specifically, when the cam surface 40a is located as shown by the solid line in
Since, as a result, a combustion chamber 48 of the cylinder having the decompression device 26 and an intake air passage 50 can always communicate with each other, the in-cylinder pressure (i.e., compression pressure) in the compression stroke can be released in the cylinder the decompression device 26. Hereunder, an operation to release the compression pressure in each cylinder in this manner is referred to as a “decompression operation”
According to the decompression device 26 configured as described above, by operating the actuator 44 to lift the HLA 34 as described above, a “decompression operating state” in which the decompression operation is performed is achieved. On the other hand, by operating the actuator 44 such the lifting of the HLA 34 is eliminated, a “decompression stop state” in which the decompression operation is not performed is obtained (even if the crankshaft 52 is rotating). As just described, the decompression device 26 can select between the decompression operating state and the decompression stop state by controlling the actuator 44. It should be noted that the concrete configuration of a decompression device according to the present disclosure is not limited to the example shown in
Furthermore, a crank angle sensor 54 that outputs a signal responsive to the crank angle is arranged in the vicinity of the crankshaft 52 of the internal combustion engine 20.
1-1-2. Drive Motor Unit
The drive motor unit 60 is equipped with a first motor generator (M/G1) 62 and a second motor generator (M/G2) 64, which each correspond to an electric motor that can generate electric power, and a power split device 66. The motor generator 62 and the motor generator 64 are alternate current synchronous motor generators having both a function as an electric motor that outputs a torque using a supplied electric power and a function as a generator that transduces an inputted mechanical power into the electric power. The first motor generator 62 is mainly used as a generator, and the second motor generator 64 is mainly used as an electric motor. Hereunder, for ease of explanation, the first motor generator 62 is simply noted as the generator 62, and the second motor generator 64 is simply noted as the motor 64.
The internal combustion engine 20, the generator 62 and the motor 64 are coupled to wheels 70 via the power split device 66 and a speed reducer 68. The power split device 66 is, for example, a planetary gear unit and splits the torque outputted from the internal combustion engine 20 into torques of the generator 62 and the wheels 70. To be more specific, in the power split device 66: a sun gear is coupled to a rotational shaft of the generator 62; a planetary carrier is coupled to the crankshaft 52 of the internal combustion engine 20; and a ring gear is coupled to a rotational shaft of the motor 64. The torque outputted from the internal combustion engine 20 or the torque outputted from the motor 64 is transmitted to the wheels 70 via the speed reducer 68. The generator 62 regenerates electric power using a torque supplied from the internal combustion engine 20 via the power split device 66.
The generator 62 and the motor 64 each perform the supply and receipt of the electric power with a battery 76 via an inverter 72 and a converter 74. The inverter 72 converts the direct current of the electric power stored in the battery 76 into the alternate current to supply the motor 64 with this alternate current, and converts the alternate current of the electric power generated by the generator 62 into the direct current to store the battery 76. As a result, the battery 76 is charged with the electric power generated by the generator 62, and the electric power stored in the battery 76 is discharged when it is consumed by the motor 64.
According to the power train 10 configured as described above, cranking for the start-up of the internal combustion engine 20 is performed by the use of the generator 62 that serves as an electric motor. That is to say, the cranking of the internal combustion engine 20 is performed by the use of the generator 62 coupled to the internal combustion engine 20 without a clutch interposed therebetween. It should be noted that the generator 62 corresponds to an example of the “electric motor” according to the present disclosure.
1-1-3. Control Device
The hybrid vehicle according to the present embodiment is provided with a control device 80 for controlling the power train 10. The control device 80 is an electronic control unit (ECU) that includes at least one processor, at least one memory, and an input/output interface.
The input/output interface receives sensor signals from various sensors mounted on the internal combustion engine 20 and the hybrid vehicle on which the internal combustion engine 20 is mounted, and also outputs actuating signals to various actuators for controlling the operation of the internal combustion engine 20 and the hybrid vehicle. The various sensors described above include the crank angle sensor 54. The control device 80 can calculate an engine speed NE by the use of the signal of the crank angle sensor 54. Furthermore, the various actuators described above include the fuel injection valves 22, the ignition device 24, the decompression devices 26 (actuators 44) and the motor generators 62 and 64 that are described above.
In the memory of the control device 80, various programs and various data (including maps) for controlling the hybrid vehicle are stored. The processor executes the programs stored in the memory. As a result, various functions of the control device 80 (such as, engine control and vehicle running control) are achieved. It should be noted that the control device 80 may alternatively be configured with a plurality of ECUs.
1-1-4. Example of Selection of Cylinders Having Decompression Device
As shown in
1-2. Control of Decompression Device
According to the in-line four-cylinder internal combustion engine 20, the compression stroke arrives at 180 degrees CA interval. Because of this, if the decompression devices 26 of the cylinders #2 and #3 are each in the decompression stop state, the compression is periodically produced (that is, the compressions is produced twice per revolution of the crankshaft 52) in the respective cylinders #1 to #4 at 180 degrees CA interval in order according to the firing order. The work of this compression becomes a key factor of the engine speed fluctuation. It should be noted that, more strictly, the engine speed fluctuation that becomes a factor of resonance affects not only the compression stroke in which the compression is produced but also the expansion stroke in which the compression is released.
As described above, the internal combustion engine 20 is coupled to the drive motor unit 60 without a clutch interposed therebetween. Because of this, the compression of the internal combustion engine 20 that is periodically produced as described above serves as an excitation force that affects the drive motor unit 60. The drive motor unit 60 has a normal frequency depending on its size. Thus, in the decompression stop state, when the engine speed NE passes through a range (which corresponds to a “first power train resonance range” shown in
Accordingly, in the course of the engine stop, the control device 80 controls the decompression devices 26 such that the decompression operating state is selected before the first power train resonance range is reached. In addition, in the course of the engine start-up that is reached with the decompression operating state, the control device 80 controls the decompression devices 26 such that the decompression stop state is selected after passage of the first power train resonance range. It should be noted that, if, contrary to the above, the course of the engine start-up is reached with the decompression stop state, the control device 80 may control the decompression devices 26 such that the decompression operating state is selected before the first power train resonance range is reached and may also control the decompression devices 26 such that the decompression stop state is selected after passage of the first power train resonance range.
It should be noted that the “course of engine stop” mentioned here corresponds to a duration from the start of fuel cut for an engine stop until the completion of the engine stop (i.e., engine speed NE=0). Also, the “course of engine start-up” corresponds to a duration from the start of cranking until the start of fuel injection. In addition, in the internal combustion engine 20 that is coupled to the drive motor unit 60, the engine stop can be performed while the energization to the generator (M/G1) 62 is stopped.
1-3. Advantageous Effects Associated with Selection of Cylinders Having Decompression Device
The firing order of the internal combustion engine 20 is #1, #3, #4 to #2 as described above. For comparison with the internal combustion engine 20 according to the present embodiment,
On the other hand, according to the internal combustion engine 20 of the present embodiment, the decompression device 26 is installed for each of the second cylinder #2 and the third cylinder #3. Because of this, if all the decompression devices 26 (i.e., two decompression devices 26) of the internal combustion engine 20 are each in the decompression operating state, the compression can be prevented from being sequentially produced in the cylinders that are adjacent to each other in terms of the firing order as shown in
An engine speed value NE1 in
On the other hand, if both the decompression devices 26 in the second cylinder #2 and the third cylinder #3 are put in the decompression operating state in the internal combustion engine 20 according to the present embodiment, the period of the excitation can be made longer as described above. Therefore, even if the engine speed NE passes through the first power train resonance range, the resonance in the power train 10 is reduced.
An engine speed value NE2 in
As described above, the subset of one or more cylinders (#2 and #3) are selected to install the decompression devices 26 such that the compression is not sequentially produced in the cylinders that are adjacent to each other in terms of the firing order, whereby the engine speed range (i.e., power train resonance range) in which the resonance is produced in the power train 10 can be made higher. As a result, even in the internal combustion engine 20 in which the decompression devices 26 are installed for only the subset of one or more cylinders, the resonance can be reduced while the engine speed Ne passes through the first power train resonance range, similarly to the example in which the decompression devices 26 are arranged in the all the cylinders. Therefore, the vibration and noise of the hybrid vehicle in the first power train resonance range can be reduced.
1-4. Other Examples of Cylinders in which Decompression Devices is Installed for in-Line Four-Cylinder Engine
According to the first embodiment described above, the decompression device 26 of the internal combustion engine 20 whose firing order is the first cylinder #1, the third cylinder #3, the fourth cylinder #4 and the second cylinder #2 is installed for each of the second cylinder #2 and the third cylinder #3. Instead of this kind of example, the decompression device 26 may be installed for each of the first cylinder #1 and the fourth cylinder #4. Alternatively, even in an in-line four-cylinder engine whose firing order is different from that in the example described above, the decompression device 26 may be installed for each of the subset of one or more cylinders that are selected such that the compression is not sequentially produced in the cylinders that are adjacent to each other in terms of the firing order, similarly to the example described above.
Furthermore, another example of the “subset of one or more cylinders” in an in-line four-cylinder engine may be any desired combination of three cylinders. Even in this kind of example, the compression can be prevented from being sequentially produced in cylinders that are adjacent to each other in terms of the firing order. In addition, according to this example, the period of the excitation in the decompression operating state becomes even longer than that in the first embodiment. As a result, an engine speed range in which the resonance is produced in the power train 10 is made even higher.
Next, a second embodiment according to the present disclosure will be described with reference to
2-1. Control of Decompression Device
2-1-1. Control in Course of Engine Start-Up
According to the example shown in
According to the example shown in
2-1-2. Control in Course of Engine Stop
The control of the decompression device 26 in the course of the engine stop is performed in the same way as that of the control in the course of the engine start-up described above. In detail, in the course of the engine stop, it is required, in order to reduce the resonance when passing through the first power train resonance range, to control the decompression devices 26 in the second cylinder #2 and the third cylinder #3 such that the decompression stop state is achieved before passing through the first power train resonance range (i.e., before reaching the upper limit value TH2 thereof). However, if the engine speed NE at which this switching to the decompression stop state is performed is too high, the resonance may be produced during passage of the second power train resonance range.
Accordingly, according to the present embodiment, the switching from the decompression stop state to the decompression operating state in the course of the engine stop is performed in the above-mentioned intermediate range (TH2<NE<TH3).
2-2. Processing of ECU Concerning Control of Decompression Device
2-2-1. Processing of Course of Engine Start-up
According to the routine shown in
If the determination result of step S100 is negative, the present routine is ended. If, on the other hand, the determination result of step S100 is positive, the control device 80 determines whether or not the engine speed NE is lower than a predetermined speed threshold value (i.e., the lower limit value TH1 of the first power train resonance range) (step S102).
If the determination result of step S102 is positive (NE<TH1), the control device 80 controls the decompression device 26 in the second cylinder #2 and the third cylinder #3 such that the decompression operating state is selected (step S104). It should be noted that, if the processing proceeds to step S104 during the decompression operating state being already selected, the decompression operating state is maintained.
If, on the other hand, the determination result of step S102 is negative (NE≥TH1), the processing proceeds to step S106. In step S106, the control device 80 determines whether or not the engine speed NE is in the above-mentioned intermediate range (TH2<NE<TH3). As a result, if the determination result of step S106 is positive, the control device 80 controls the decompression device 26 in the second cylinder #2 and the third cylinder #3 such that the decompression stop state is selected (step S108). It should be noted that, if the processing proceeds to step S108 during the decompression stop state being already selected, the decompression stop state is maintained.
If, on the other hand, the determination result of step S106 is negative (TH1≤NE≤TH2, or NE≥TH3), the processing proceeds to step S110. In step S110, the control device 80 determines whether or not the engine speed NE is higher than or equal to a predetermined speed threshold value (i.e., the lower limit value TH3 of the second power train resonance range).
If the determination result of step S110 is negative (that is, TH1≤NE≤TH2), the control device 80 proceeds to step S104 to select (continue) the decompression operating state. If, on the other hand, the determination result of step S110 is positive (NE≥TH3), the control device 80 proceeds to step S108 to select (continue) the decompression stop state.
2-2-2. Processing of Course of Engine Stop
According to the routine shown in
If the determination result of step S200 is negative, the present routine is ended. If, on the other hand, the determination result of step S200 is positive, the control device 80 executes the determination of step S110. If, as a result, this determination result is positive (NE≥TH3), the control device 80 controls the decompression devices 26 such that the decompression stop state is selected (step S108).
If, on the other hand, the determination result of step S110 is negative (NE<TH3), the control device 80 executes the determination of step S106. If, as a result, this determination result is positive (TH2<NE<TH3), the control device 80 controls the decompression devices 26 such that the decompression operating state is selected (step S104).
If, on the other hand, the determination result of step S106 is negative (NE≤TH2), the control device 80 executes the determination of step S102. If, as a result, this determination result is negative (TH1≤NE≤TH2), the control device 80 proceeds to step S104 to select (continue) the decompression operating state. If, on the other hand, the determination result of step S102 is positive (NE<TH1), the control device 80 proceeds to step S108 to select (continue) the decompression stop state.
2-3. Advantageous Effects Concerning Control of Decompression Devices
According to the routine shown in
Moreover, according to the routine shown in
According to the control of the decompression device 26 of the present embodiment described so far, not only the resonance due to the passage of the first power train resonance range but also the resonance due to the passage of the second power train resonance range with the decompression operating state can be reduced in the course of the engine start-up and course of the engine stop. Therefore, the vibration and noise of the hybrid vehicle can be properly reduced while reducing cost due to a decrease of the cylinders having the decompression device 26.
In addition, it is supposed that, contrary to the example described with reference to
Next, a third embodiment according to the present disclosure will be described with reference to
3-1. Example of Selection of Cylinder Having Decompression Device in in-Line Two-Cylinder Engine
It should be noted that the control of the decompression device 26 described in the second embodiment may alternatively be performed for the internal combustion engine 90 in which the decompression device 26 is installed only in the subset of one or more cylinders (#2). This also applies to fourth to sixth embodiments described later.
3-2. Another Example of Selection of Cylinder Having Decompression Device in in-Line Two-Cylinder Engine
A cylinder having the decompression device 26 in the in-line two-cylinder internal combustion engine 90 may be the first cylinder #1 instead of the example described above.
Next, a fourth embodiment according to the present disclosure will be described with reference to
4-1. Example of Selection of Cylinders Having Decompression Device in in-Line Three-Cylinder Engine
4-2. Another Example of Selection of Cylinders Having Decompression Device in In-Line Three-Cylinder Engine
The cylinders having the decompression device 26 in the in-line three-cylinder internal combustion engine 92 may be a combination of the first cylinder #1 and the third cylinder #3 or a combination of the first cylinder #1 and the second cylinder #2, instead of the example described above.
Next, a fifth embodiment according to the present disclosure will be described with reference to
5-1. Example of Selection of Cylinders Having Decompression Device in V-Type Six-Cylinder Engine
An example of the firing order in this internal combustion engine 94 is #1, #2, #3, #4, #5 and #6. In the example shown in
5-2. Another Example of Selection of Cylinders Having Decompression Device in V-Type Six-Cylinder Engine
An example of the cylinders having the decompression device 26 in the V-type six-cylinder internal combustion engine 94 may be a combination of the second cylinder #2, the fourth cylinder #4 and the six cylinder #6, instead of the example described above. Also, the decompression devices 26 may alternatively be installed for any one of the following combinations of four cylinders, that is, a combination of #1, #2, #4 and #5, a combination of #2, #3, #5 and #6, and a combination of #3, #4, #6 and #1. Furthermore, another example of the cylinders (i.e., a subset of one or more cylinders) having the decompression device 26 may be any desired combination of five cylinders.
Next, a sixth embodiment according to the present disclosure will be described with reference to
6-1. Example of Selection of Cylinders Having Decompression Device in V-Type Eight-Cylinder Engine
6-2. Another Example of Selection of Cylinders Having Decompression Device in V-Type Eight-Cylinder Engine
An example of the cylinders having the decompression device 26 in the V-type eight-cylinder internal combustion engine 96 may be a combination of #1, #4, #6 and #7 that is another example in which a compression-occurrence cylinder and a non-compression-occurrence cylinder are alternately repeated, similarly to the example described above. Also, an example in which three non-compression cylinders are successive, such as, a combination of #8, #4, #3, #5, #7 and #2, a combination of #4, #3, #6, #7, #2 and #1, a combination of #3, #6, #5, #2, #1 and #8, or a combination of #6, #5, #7, #1, #8 and #4 may correspond to another example of the cylinders having the decompression device 26. Moreover, an example with unequal intervals according to the order from one compression-occurrence cylinder, two non-compression-occurrence cylinders, one compression-occurrence cylinder, two non-compression-occurrence cylinders, one compression-occurrence cylinder and one non-compression-occurrence cylinder (for example, a combination of #8, #4, #6, #5 and #2) may correspond to still another example of the cylinders having the decompression device 26. Furthermore, yet another example of the cylinders (i.e., a subset of one or more cylinders) having the decompression device 26 may be any desired seven cylinders.
7-1. Other Examples of Internal Combustion Engine
The number and arrangement of cylinders of the internal combustion engine according to the present disclosure are not limited to the examples of the first to sixth embodiments described above. That is to say, any desired number of cylinders of the internal combustion engine may be available as long as it is plural, and the arrangement of cylinders may not always be of the in-line type and the V-type and, for example, be of horizontally opposed type or W-type.
7-2. Another Example of Execution Timing of Control of Decompression Device
In the first and second embodiments, the examples in which the control of the decompression device 26 is performed in both the course of the engine stop and the course of the engine start-up have been described. However, the control of the decompression device according to the present disclosure may alternatively be performed in only either one of the course of the engine stop and the course of the engine start-up.
7-3. Other Examples of Drive Motor Unit and Power Train
The “drive motor unit” according to the present disclosure is not limited to the foregoing, as long as it is available to drive a vehicle and includes an electric motor that is coupled to an internal combustion engine without a clutch interposed therewith (i.e., an electric motor that is available to perform cranking of the internal combustion engine). Moreover, “an electric motor that is coupled to an internal combustion engine without a clutch interposed between the drive motor unit and the internal combustion engine” may not always serve mainly as a generator as with the generator 62 of the drive motor unit 60. That is to say, in the hybrid vehicle according to the present disclosure, an electric motor included in a drive motor unit for driving the vehicle may alternatively be used as an “electric motor” that is available to perform cranking of an internal combustion engine. As just described, “an electric motor that is coupled to an internal combustion engine without a clutch” is not always required to be used to drive a hybrid vehicle, as long as it generates an energy for driving the vehicle (i.e., a driving force for the vehicle, or an electric power for driving the vehicle). Furthermore, the “power train” of the hybrid vehicle according to the present disclosure may be, for example, be of series type using the internal combustion engine 20 only for electric power generation, instead of the type using, as its power source, both the internal combustion engine 20 and the drive motor unit 60 (i.e., torque-split type, such as the power train 10 provided with the drive motor unit 60, or parallel type).
The embodiments and modification examples described above may be combined in other ways than those explicitly described above as required and may be modified in various ways without departing from the scope of the present disclosure.
Number | Date | Country | Kind |
---|---|---|---|
2018-040786 | Mar 2018 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
20120304945 | Nakamura | Dec 2012 | A1 |
20130030624 | Suyama | Jan 2013 | A1 |
20150134171 | Asami | May 2015 | A1 |
20180283343 | Wabbals | Oct 2018 | A1 |
20190301419 | Miyashita | Oct 2019 | A1 |
20200072134 | Hotta | Mar 2020 | A1 |
Number | Date | Country |
---|---|---|
2014-047695 | Mar 2014 | JP |
Number | Date | Country | |
---|---|---|---|
20190277240 A1 | Sep 2019 | US |