JP2020067005A - Internal combustion engine and vehicle system having the same - Google Patents

Abstract

To provide an internal combustion engine which allows the fine adjustment of an engine brake force, and a vehicle system having the same.SOLUTION: An internal combustion engine 10 comprises: a cylinder block 14 having a bulkhead 34 which is formed so as to partition a plurality of cylinders 12 to each cylinder; a crank chamber 32 having a region 32a which is partitioned at each cylinder by the bulkhead 34, and a communication part 32b communicating between the plurality of cylinders 12; and a passage cross section variable device 40 which can switch a passage cross section of the communication part 32b in a direction perpendicular to an axial direction of a crankshaft 20 to at least three stages.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an internal combustion engine and a vehicle system including the same.

  For example, Patent Document 1 discloses an engine braking device that assists the braking force of a vehicle. An internal combustion engine to which this engine braking device is applied includes a plurality of partition walls (including a bearing portion of a crankshaft) that partition the inside of a crankcase for each cylinder. The engine braking device includes vent holes provided in the partition walls and throttle valves provided in the vent holes. The vent hole is provided in the bearing portion and allows free pressure movement between adjacent chambers in the crankcase. The throttle valve is controlled to the fully open position during normal engine operation. During engine braking (that is, when the engine brake is operating), the operating state of the throttle valve is changed according to the on / off state of the switch operated by the driver of the vehicle. More specifically, when the switch is off (when there is no demand for increasing engine braking), the throttle valve is controlled to the fully open position, while when the switch is on (when there is a demand for increasing engine braking). In the case), the throttle valve is controlled to a half-open position that brings the vent hole into a predetermined half-open state. As a result, the pumping loss of the internal combustion engine is increased and the engine braking force is increased compared to when the switch is off. As a result, the braking force of the vehicle is increased.

Japanese Utility Model Publication No. 06-047636

  According to the technique described in Patent Document 1 described above, the operating state of the throttle valve is changed depending on whether there is a request to increase the engine braking force. Therefore, the engine braking force cannot be finely adjusted.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an internal combustion engine capable of finely adjusting the engine braking force and a vehicle system including the internal combustion engine.

The internal combustion engine according to the present invention,
A cylinder block having a partition wall formed to partition a plurality of cylinders into cylinders;
With a portion partitioned for each cylinder by the partition wall, a crank chamber having a communication portion that communicates between the plurality of cylinders,
A passage cross-sectional area varying device configured to be able to switch the passage cross-sectional area of the communication part in at least three stages in a direction perpendicular to the axial direction of the crankshaft,
Equipped with.

  The passage sectional area varying device may include an oil tank that stores oil outside the crank chamber. The passage cross-sectional area changing device switches the passage cross-sectional area by moving oil back and forth between the oil tank and the crank chamber to change the oil level height of the oil in the crank chamber. May be configured as.

  The passage cross-sectional area varying device may include a hose connecting the oil tank and the communication portion, and a tank position adjusting mechanism for vertically moving the oil tank in the vertical direction.

  The passage cross-sectional area varying device is arranged in an oil supply flow passage that connects the oil tank and the communication portion, and an oil that pressure-feeds the oil from the oil tank toward the communication portion. A pump, an oil return flow passage having one end connected to the communication portion and the other end lower than the one end in the vertical direction connected to the oil tank, and an oil return flow passage arranged in the oil return flow passage, A valve configured to open when the oil is collected in the oil tank.

  The passage cross-sectional area varying device may include an oil flow path that connects the oil tank and the communication portion, a piston arranged in the oil tank, and a piston drive mechanism that reciprocates the piston. . The passage cross-sectional area changing device supplies oil from the oil tank to the communication portion via the oil flow path when the piston is displaced in the oil tank in the first direction. May be configured to recover the oil in the communication section into the oil tank via the oil flow path when the oil is displaced in the second direction opposite to the first direction.

  The passage cross-sectional area changing device includes an oil flow path that connects the oil tank and the communication portion, a volume adjuster disposed in the oil tank, and a volume adjuster drive that takes the volume adjuster into and out of oil. And a mechanism. Further, the passage cross-sectional area varying device, when increasing the volume of the volume adjuster in the oil using the volume adjuster drive mechanism, transfers oil from the oil tank to the communicating portion via the oil flow path. When the volume of the volume adjuster in the oil is reduced by using the volume adjuster drive mechanism, the oil in the communicating portion is recovered into the oil tank via the oil flow path. It may be configured.

  The internal combustion engine may include an oil pan chamber that communicates with the crank chamber and is formed below the crank chamber. The passage sectional area changing device may be configured to change the passage sectional area by changing the volume of the oil pan chamber to change the oil surface height of the oil in the crank chamber.

  The communication section may include a vent hole formed in the partition wall so as to communicate between the adjacent cylinders. The passage sectional area varying device may include a shutter device that varies an opening area of the ventilation hole. The passage sectional area changing device may be configured to be able to switch the passage sectional area by changing the opening area of the ventilation hole.

A vehicle system capable of utilizing the engine brake of the above-mentioned internal combustion engine,
The vehicle system is
The internal combustion engine;
A regenerative braking device that recovers vehicle kinetic energy and converts it into electric power during deceleration of a vehicle equipped with the internal combustion engine,
A battery for storing the electric power,
A control device for controlling the internal combustion engine and the regenerative braking device,
Equipped with.
The control device is
When the vehicle is braked when the battery is in a non-fully charged state, a fuel cut process for controlling a fuel injection valve of the internal combustion engine so as to stop fuel injection, and the regenerative braking device are operated. Perform regenerative braking processing to
When the vehicle is braked when the battery is in a fully charged state, the passage cutoff is compared to when the vehicle is braked under the fuel cut process and the non-fully charged state. The passage cross sectional area reduction processing is executed to control the passage cross sectional area changing device so as to reduce the area.

  In the passage cross-section area reduction processing, the control device may control the passage cross-section area varying device such that the passage cross-section area becomes smaller as the required braking force of the vehicle is larger.

  According to the internal combustion engine of the present invention, the passage cross-sectional area of the communicating portion that communicates between the cylinders in the crank chamber can be switched in at least three stages by the passage cross-sectional area varying device. Therefore, the engine braking force can be finely adjusted.

FIG. 1 is a diagram schematically showing a configuration example of an internal combustion engine according to Embodiment 1 of the present invention. It is a schematic diagram for demonstrating an example of the specific structure of the passage cross-sectional area variable apparatus shown in FIG. FIG. 6 is a diagram for explaining the operation of the passage sectional area varying device according to the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area varying device according to a first modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area varying device according to a second modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area varying device according to a third modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area changing device according to a fourth modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area changing device according to a fifth modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area varying device according to a sixth modification example of the first embodiment of the present invention. FIG. 9 is a schematic diagram for explaining the configuration of a passage cross-sectional area changing device according to a seventh modified example of the first embodiment of the present invention. FIG. 10 is a schematic diagram for explaining the configuration of a passage cross-sectional area changing device according to an eighth modification example of the first embodiment of the present invention. FIG. 6 is a schematic diagram for explaining a configuration example of a vehicle system according to a second embodiment of the present invention. 7 is a flowchart showing a routine of processing relating to control during vehicle braking according to Embodiment 2 of the present invention. It is a figure for demonstrating the coordinated control of the engine brake and hydraulic brake which utilize the change of passage cross-sectional area. It is a flowchart which shows the routine of the process regarding the other control example at the time of vehicle braking which concerns on this invention. 9 is a flowchart showing a routine of processing relating to control during vehicle braking according to Embodiment 3 of the present invention. 6 is a graph showing a relationship between a braking force of a vehicle, a passage cross-sectional area of a communication portion, and an engine rotation speed NE. It is the figure which represented typically the structural example of the internal combustion engine which concerns on Embodiment 4 of this invention. FIG. 19 is a schematic diagram for explaining an example of a specific configuration of the shutter device shown in FIG. 18.

  In each of the embodiments described below, elements common to each drawing are denoted by the same reference numerals, and overlapping description will be omitted or simplified. Further, in the embodiments shown below, when reference is made to the number of each element, the number, the amount, the range, etc., the reference is made unless otherwise specified or in principle specified by the number. The present invention is not limited to the number. Further, the structures, steps, and the like described in the embodiments below are not necessarily essential to the present invention, unless otherwise specified or clearly specified in principle.

1. Embodiment 1
First, with reference to FIGS. 1 to 9, the first embodiment according to the present invention and its modification will be described.

1-1. Configuration Example of Internal Combustion Engine FIG. 1 is a diagram schematically showing a configuration example of an internal combustion engine 10 according to Embodiment 1 of the present invention. The internal combustion engine 10 shown in FIG. 1 is mounted on, for example, a vehicle and used as a power source thereof. Note that FIG. 1 shows the internal combustion engine 10 when mounted on a vehicle. The vertical direction of FIG. 1 is parallel to the vertical direction. Hereinafter, in the present specification, when simply referred to as “upward” and “upward”, they indicate “upward” and “upward” in the vertical direction. This also applies to "downward" and "downward".

1-1-1. Basic Configuration of Internal Combustion Engine The internal combustion engine 10 is, for example, an in-line four-cylinder engine. That is, the internal combustion engine 10 includes a plurality of (for example, four) cylinders 12 arranged in a line in the cylinder row direction. These cylinders 12 are formed inside a cylinder block 14. A piston 16 is arranged inside each cylinder 12. Each of the pistons 16 is connected to a crankshaft 20 via a connecting rod 18. The piston 16 reciprocates in the cylinder 12 as the crankshaft 20 rotates. The crankshaft 20 has a counterweight 22 for balancing. The number of cylinders of the internal combustion engine 10 is not limited to four as long as it is two or more.

  A cylinder head 24 is attached above the cylinder block 14. A combustion chamber 26, which is a space surrounded by the cylinder head 24, the cylinder block 14, and the piston 16, is formed above the piston 16 in each cylinder 12.

  On the other hand, below the cylinder block 14, a crankcase 28 is attached. Further, below the crankcase 28, an oil pan 30 for storing engine lubricating oil (hereinafter, simply referred to as “oil”) for lubricating each part of the internal combustion engine 10 is attached. A crank chamber 32, which is a space surrounded by the cylinder block 14, the crankcase 28, and the oil pan 30, is formed on the opposite side of the combustion chamber 26 via the piston 16.

  Further, the cylinder block 14 has a plurality of (three in the example of FIG. 1) partition walls 34 formed therein so as to partition all the cylinders 12 of the internal combustion engine 10 for each cylinder. The crankshaft 20 is rotatably supported by a partition wall 34 (cylinder block 14), a crankcase 28, and a crankcap 36 via bearings (not shown).

  Further, each partition wall 34 is formed with a ventilation hole (communication hole) 38 for communicating the crank chamber 32 between adjacent cylinders. More specifically, the vent hole 38 is formed in the partition wall 34 below the piston bottom dead center position. By allowing the gas flow (breathing) between the adjacent cylinders by such a vent hole 38, it becomes possible to absorb the pressure difference (pressure fluctuation) between the adjacent cylinders due to the vertical movement of the piston 16. As a result, the pumping loss of the internal combustion engine 10 can be reduced.

(Communication part)
A portion 32 a of the crank chamber 32 above the ventilation hole 38 is partitioned by a partition wall 34 for each cylinder. The crank chamber 32 includes a "communication portion 32b" that communicates between a plurality of cylinders (between all cylinders in the example shown in FIG. 1) together with this portion 32a.

  More specifically, the communication portion 32b includes the ventilation hole 38. Further, regarding the portion below the crankshaft 20, the cylinders communicate with each other between the connecting rod 18, the counterweight 22, and the crank cap 36 and the oil level of the oil stored in the oil pan 30. There is. Therefore, this portion is also included in the communication portion 32b. Therefore, in FIG. 1, the portion surrounded by the broken line corresponds to an example of the communication portion 32b.

1-1-2. Configuration of Passage Cross Section Variable Device In the example shown in FIG. 1, the upper end of the communicating portion 32b in the vertical direction is specified by the upper surface of the ventilation hole 38, and the lower end of the communicating portion 32b in the same direction is specified by the oil surface on the oil pan 30. To be done. Here, the (respiratory) passage cross-sectional area (gap area) of the communication portion 32b in the direction perpendicular to the axial direction of the crankshaft 20 is at the position A (the axial position of the crankshaft 20) where the vent hole 38 is present. It will be the maximum. The “passage cross-sectional area of the communication portion 32b” in the following description refers to the passage cross-sectional area at this position A.

  The internal combustion engine 10 of the present embodiment includes a passage sectional area varying device (hereinafter, simply referred to as “variable device”) 40 that varies the passage sectional area of the communication portion 32b. The variable device 40 is configured to change the passage cross-sectional area by changing the vertical width of the communication portion 32b by adjusting the oil surface height Hc in the crank chamber 32.

  FIG. 2 is a schematic diagram for explaining an example of a specific configuration of the passage sectional area changing device 40 shown in FIG. The variable device 40 includes an oil tank 42, an oil hose 44, and a tank position adjusting mechanism 46. The oil tank 42 is provided outside the crank chamber 32 and stores oil (engine lubricating oil). The oil hose 44 has flexibility and connects the oil tank 42 and the communication portion 32b. More specifically, in the example shown in FIG. 2, the oil hose 44 connects the lower portion of the oil tank 42 and the lower portion of the communication portion 32b. The oil hose 44 corresponds to an example of the "hose" according to the present invention.

  The tank position adjusting mechanism 46 is configured to vertically move the oil tank 42. In the example shown in FIG. 2, the tank position adjusting mechanism 46 includes a shaft 48 having a screw portion 48a formed on the outer peripheral surface, and an electric motor 50. Specifically, the shaft 48 is arranged so as to extend along the vertical direction. The oil tank 42 is installed on the upper end of the shaft 48. The electric motor 50 includes a rotor (not shown) formed in an annular shape. The shaft 48 is inserted inside the rotor. A screw that meshes with the screw portion 48a of the shaft 48 is cut on the inner peripheral surface of the rotor. The electric motor 50 is attached to the internal combustion engine 10 via a support member (not shown), and thus the position of the electric motor 50 is fixed. The electric motor 50 is, for example, a stepping motor. Further, the tank position adjusting mechanism 46 includes a guide rail 52 that guides the oil tank 42 in the vertical direction. The guide rail 52 is attached to the internal combustion engine 10.

  According to the tank position adjusting mechanism 46 configured as described above, the rotational movement of the electric motor 50 can be converted into the linear movement of the shaft 48 by operating the electric motor 50. Therefore, the vertical position of the oil tank 42 in the vertical direction can be adjusted by controlling the rotational position of the electric motor 50. The electric motor 50 and the guide rail 52 may be fixed to the vehicle body instead of the internal combustion engine 10.

  The variable device 40 further includes a gas hose 54 in order to smoothly move the oil between the oil tank 42 and the communication portion 32b, which will be described in detail later with reference to FIG. The gas hose 54 is flexible and connects the upper portion of the oil tank 42 and the cylinder head cover 56 provided above the cylinder head 24.

  The internal combustion engine 10 further includes a control device 60 that controls the internal combustion engine 10. The control device 60 is an electronic control unit (ECU) having a processor 60a and a memory 60b. The memory 60b stores a program for controlling the internal combustion engine 10. The processor 60a reads the program from the memory 60b and executes it. The control device 60 takes in sensor signals from various sensors for controlling the internal combustion engine 10. Further, the processor 60a executes various programs using the fetched sensor signals and outputs operation signals for operating various actuators of the internal combustion engine 10. As a result, various engine controls such as fuel injection control and intake air amount control are executed. The control of the internal combustion engine 10 by the control device 60 includes control of the variable device 40 (electric motor 50). The control device 60 may be composed of a plurality of ECUs.

1-2. Operation of passage cross-sectional area changing device FIGS. 3A to 3C are diagrams for explaining the operation of the passage cross-sectional area changing device 40 according to the first embodiment of the present invention. In the present embodiment, the control device 60 can switch the passage cross-sectional area of the communication portion 32b in three stages by switching the position of the oil tank 42 in the vertical direction in three stages.

  First, in FIG. 3A, the position of the oil tank 42 is controlled so that the passage cross-sectional area of the communication portion 32b is maximized (in other words, the oil level Hc in the crank chamber 32 is minimized). It shows the state of being performed. In this control state, the amount of oil recovered from the communication portion 32b into the oil tank 42 is maximum. In order to realize this control state, the position of the oil tank 42 is controlled so that the upper surface of the oil tank 42 is lower than the lower end of the communicating portion 32b (the oil surface height Hc assumed in this control state). . Hereinafter, this control state is also referred to as a "fully open state" of the communication portion 32b.

  When the oil tank 42 is moved upward from the fully opened state shown in FIG. 3A, the oil in the oil tank 42 is supplied into the communicating portion 32b via the oil hose 44 by its own weight. At this time, the gas in the communication portion 32b (gas in the crankcase) is introduced into the cylinder head cover 56 via the blow-by gas passage (not shown), and further introduced into the oil tank 42 via the gas hose 54. . That is, the gas in the communication portion 32b is replaced by the oil, and the oil in the oil tank 42 is replaced by the gas. Since the gas hose 54 is provided, the oil can be smoothly moved.

  When the oil tank 42 is moved downward after the oil tank 42 is moved upward as described above, the oil in the communication portion 32b is transferred to the oil tank 42 via the oil hose 44, contrary to the time when the oil tank 42 is moved upward. Move in (collected). At this time, the gas in the oil tank 42 is introduced (returned) into the communication portion 32b via the gas hose 54.

  Next, in FIG. 3 (B), the position of the oil tank 42 is set so that the passage cross-sectional area becomes zero (minimum) (in other words, the oil level height Hc that closes the vent hole 38 with oil is obtained). It shows a controlled state. In this control state, the oil is supplied into the communication portion 32b so that the oil in the oil tank 42 is substantially emptied. In order to realize this control state, the position of the oil tank 42 is controlled so that the lower surface of the oil tank 42 is higher than the upper end of the communication portion 32b (the oil surface height Hc assumed in this control state). . Hereinafter, this control state is also referred to as a "fully closed state" of the communication portion 32b.

  Finally, FIG. 3 (C) shows a state in which the position of the oil tank 42 is controlled so that the passage cross-sectional area which is half the passage cross-sectional area in the fully opened state shown in FIG. 3 (A) is obtained. . In this state, the cross-sectional area of the ventilation hole 38 and the cross-sectional area of the opening located above the oil level on the lower side of the crankshaft 20 correspond to the passage cross-sectional area of the communication portion 32b. The position of the oil tank 42 for realizing this control state can be obtained by performing calculations or experiments in advance. Hereinafter, this control state is also referred to as a “half-open state” of the communication portion 32b.

  In addition, as can be understood from the above description, the oil tank 42 changes from the fully closed oil surface height Hc shown in FIG. 3 (B) to the fully opened oil surface height Hc shown in FIG. 3 (A). It has the capacity to accommodate the required amount of oil for the change. The supply of oil to each part of the internal combustion engine 10 that requires lubrication with oil is performed by a general lubricating system (not shown) including an oil pump.

1-3. Effects As described above, according to the variable device 40, the oil is moved back and forth between the oil tank 42 and the crank chamber 32 to change the oil level height Hc in the crank chamber 32, so that the communication portion 32b is formed. The passage cross-sectional area can be switched.

  When the oil surface height Hc is increased by the variable device 40, the passage cross-sectional area of the communication portion 32b of the crank chamber 32 is reduced. As a result, the pumping loss increases and the engine braking force also increases. Then, according to the variable device 40, the communication portion 32b can be switched to three stages of the fully open state, the half open state, and the fully closed state. Therefore, the engine braking force can be finely adjusted as compared with an engine braking device that can switch the open state of the vent hole in two steps.

  More specifically, for example, the control device 60 fully opens the communication part 32b at the time of high rotation of the internal combustion engine 10, while making the control state of the communication part 32b half open or when the engine braking force is required. Fully closed. As a result, it is possible to improve the fuel consumption by reducing pumping loss at the time of high rotation and to finely adjust the engine braking force when the engine braking force is required. Further, as shown in FIGS. 3B and 3C, in the half open state and the fully closed state, the rotating counterweight 22 is immersed in oil. Therefore, compared with the fully opened state, the engine braking force can be increased by also utilizing the oil stirring resistance of the counterweight 22.

  In addition, in the present embodiment, the internal combustion engine 10 is mounted on the vehicle as a power source thereof, and thus can be connected to the wheels. Therefore, the engine braking force can be finely adjusted, so that the vehicle braking force can be finely adjusted.

1-4. Modification of Embodiment 1 1-4-1. Another example of switching the passage cross-sectional area In the above-described first embodiment, the variable device 40 is configured such that the passage cross-sectional area of the communication portion 32b can be switched in three stages. However, the “passage cross-sectional area varying device” according to the present invention may be configured so that the passage cross-sectional area can be switched in four or more stages, instead of the above example. Specifically, by setting the control position of the oil tank 42 for adjusting the oil level height Hc more finely than in the example shown in FIGS. 3A to 3C, the oil level height Hc can be changed in four or more steps. As a result, the passage cross-sectional area can be switched in four or more stages. As a result, the engine braking force can be adjusted more finely.

  Further, when the passage cross-sectional area is switched to at least three stages, as a result, the controllable states of the communicating portion are not limited to the fully open state (see FIG. 3A) and the fully closed state (see FIG. 3B). At least one of them may not be included. That is, the control state of the communication unit may be configured only by a plurality of intermediate control states other than the fully open state and the fully closed state, instead of the above example, or with the plurality of intermediate control states. It may be configured by one of a fully open state and a fully closed state.

1-4-2. Another example of variable passage cross-sectional area device (first modification)
FIG. 4 is a schematic diagram for explaining the configuration of a passage sectional area varying device 70 according to a first modified example of the first embodiment of the present invention. The variable device 70 shown in FIG. 4 includes a seesaw-type tank position adjusting mechanism 72 for moving the oil tank 42 up and down in the vertical direction. Specifically, the tank position adjusting mechanism 72 includes a support base 74, a lever 76, and an electric motor 78.

  The lever 76 is formed in an elongated shape and rotates about a fulcrum 74 a provided on the support base 74. One end 76 a of the lever 76 is rotatably attached to the oil tank 42. The portion of the lever 76 located on the opposite side of the one end 76a via the fulcrum 74a includes a screw portion 76b and a rail portion 76c. The lever 76 is formed such that the length from the fulcrum 74a to the one end 76a is longer than the length from the fulcrum 74a to the other end 76d.

  The screw portion 76b and the rail portion 76c are formed so as to be parallel to each other and extend in the longitudinal direction of the lever 76. The electric motor 78 has a screw portion (not shown) meshed with the screw portion 76b. The electric motor 78 is configured to reciprocate along the screw portion 76b while being guided by the rail portion 76c during its operation.

  According to the tank position adjusting mechanism 72 configured as described above, when the electric motor 78 is operated so as to approach the fulcrum 74a, the oil tank 42 pushes the lever 76 more than the force by which the electric motor 78 functioning as a weight pushes down the lever 76. The pushing force becomes larger, and the oil tank 42 moves downward. On the contrary, when the electric motor 78 is operated to move away from the fulcrum 74a, the force by which the electric motor 78 pushes down the lever 76 becomes larger than the force by which the oil tank 42 pushes down the lever 76, and the oil tank 42 moves upward. As described above, according to the tank position adjusting mechanism 72, the vertical position of the oil tank 42 in the vertical direction can be adjusted by controlling the position of the electric motor 78 on the lever 76.

(Second modified example)
FIG. 5 is a schematic diagram for explaining the configuration of a passage sectional area varying device 80 according to a second modified example of the first embodiment of the present invention. The variable device 80 shown in FIG. 5 includes a rope type tank position adjusting mechanism 82 for vertically moving the oil tank 42. Specifically, the tank position adjusting mechanism 82 includes an electric hoist 86 for hoisting a rope 84, one end of which is fixed to the upper portion of the oil tank 42, and a mechanism for reducing the driving force of the hoist 86 ( Includes a rope 88, a counterweight 90 and a pulley 92). The rope 88 wound around the pulley 92 has one end fixed to the upper portion of the oil tank 42 and the other end fixed to the upper portion of the counterweight 90.

  According to the tank position adjusting mechanism 82 configured as described above, when the hoisting machine 86 is rotated in the direction in which the rope 84 is wound up, the oil tank 42 moves upward. Further, when the hoisting machine 86 is rotated in the reverse direction, the oil tank 42 moves downward. As described above, according to the tank position adjusting mechanism 82, the vertical position of the oil tank 42 in the vertical direction can be adjusted by controlling the rotational position of the hoisting machine 86. The rope 84 and the hoisting machine 86 may be omitted by adopting a configuration in which the pulley 92 is driven by an electric motor.

(Third modification)
FIG. 6 is a schematic diagram for explaining the configuration of a passage sectional area varying device 100 according to a third modification of the first embodiment of the present invention. The variable device 100 shown in FIG. 6 includes an oil tank 102, an oil supply passage 104, an oil pump 106, an oil return passage 108, and a valve 110.

  The oil tank 102 has the same oil capacity as the oil tank 42. The oil supply flow path 104 connects the oil tank 102 and the communication portion 32b (for example, a lower portion thereof). The oil pump 106 is, for example, an electric type, is arranged in the oil supply flow path 104, and pumps the oil from the oil tank 102 toward the communication portion 32b. The oil return passage 108 has one end connected to the communication portion 32b (for example, a lower portion thereof), and the other end connected to the oil tank 42 at a position lower than the one end in the vertical direction. The valve 110 is, for example, a solenoid valve, is arranged in the oil return flow path 108, and is configured to open when the oil in the communication portion 32b is collected in the oil tank 102.

  In the variable device 100 configured as described above, unlike the example in which the oil tank 42 is moved up and down, the position of the oil tank 102 is fixed to the internal combustion engine 10 via a support member (not shown). . When supplying the oil in the oil tank 102 to the communication portion 32b, the oil pump 106 is driven with the valve 110 closed. As a result, the oil is pressure-fed toward the communicating portion 32b. Further, when the oil in the communication portion 32b is collected in the oil tank 102, the valve 110 is opened with the oil pump 106 stopped. As a result, the oil is collected in the oil tank 102 by utilizing the weight of the oil. Therefore, according to the variable device 100, by controlling the discharge amount and the operating time of the oil pump 106 and the valve opening time of the valve 110, the oil surface height Hc in the crank chamber 32 (the passage cross-sectional area of the communicating portion 32b). ) Can be adjusted. Further, in order to adjust the oil level height Hc more accurately, a sensor for detecting the oil level may be attached to the oil tank 102 or the crankcase 28.

(Fourth modification)
FIG. 7 is a schematic diagram for explaining the configuration of a passage sectional area varying device 120 according to a fourth modified example of the first embodiment of the present invention. The variable device 120 shown in FIG. 7 includes an oil tank 122, an oil flow path 124, a piston 126, and a piston drive mechanism 128. The oil tank 122, the piston 126, and the piston drive mechanism 128 may be mounted on the internal combustion engine 10 via a support member (not shown), or may be mounted on the vehicle body.

  The oil tank 122 has an oil capacity similar to that of the oil tank 42, is formed in a longitudinal shape as an example, and is arranged such that its longitudinal direction is parallel to the vertical direction. The oil flow path 124 connects the oil tank 122 and the communication portion 32b (for example, a lower portion thereof). The piston 126 is disposed in the oil tank 122 so as to be capable of reciprocating, and a side surface of the piston 126 and an inner surface of the oil tank 122 facing the side surface are sealed by a seal member 130.

  The piston drive mechanism 128 uses, for example, a screw mechanism similar to the tank position adjustment mechanism 46 (see FIG. 2) to adjust the vertical position of the piston 126, and includes a shaft 48 and an electric motor 50. Further, the variable device 120 is provided with a gas flow path 132 in order to smoothly move the oil between the oil tank 122 and the communication portion 32b. The gas flow path 132 connects the upper portion of the oil tank 122 and the cylinder head cover 56.

  In the variable device 120 described above, when the oil is supplied from the oil tank 122 to the communication portion 32b through the oil flow path 124, the piston drive mechanism 128 moves the piston 126 in the upward direction of FIG. (Equivalent to an example of “first direction”). As a result, the oil in the oil tank 122 is pushed out into the communication portion 32b as the piston 126 moves up. Further, when the oil in the communicating portion 32b is collected in the oil tank 122 via the oil flow path 124, the piston drive mechanism 128 moves the piston 126 downward in FIG. 7 (“second direction” according to the present invention). Equivalent to one example). As a result, the oil in the communication portion 32b is sucked back into the oil tank 122 as the piston 126 descends. In this way, according to the variable device 120, the volume of the oil chamber in the oil tank 122 is made variable by controlling the control position (the position in the vertical direction) of the piston 126 in the oil tank 122. The oil level height Hc in 32 (passage cross-sectional area of the communicating portion 32b) can be adjusted.

(Fifth Modification)
FIG. 8 is a schematic diagram for explaining the configuration of a passage cross-sectional area changing device 140 according to a fifth modified example of the first embodiment of the present invention. Hereinafter, differences between the variable device 140 shown in FIG. 7 and the variable device 140 shown in FIG. 8 will be described.

  The variable device 140 includes an oil tank 142 having an oil capacity similar to that of the oil tank 122. The oil tank 142 is, for example, formed in a longitudinal shape, and is arranged such that its longitudinal direction is parallel to the direction perpendicular to the vertical direction (horizontal direction). A piston 126 driven by a piston drive mechanism 128 is arranged inside the oil tank 142. Therefore, the piston 126 reciprocates horizontally in the oil tank 142. One end of an oil flow path 144 that connects the oil tank 142 and the communication portion 32b is connected to one end of the oil tank 142 in the horizontal direction. This end is the end toward which the piston 126 approaches when the volume of the oil chamber in the oil tank 142 is minimized. Then, one end of the gas flow passage 146 is connected to this end portion at a position vertically above the connection position of the oil flow passage 144.

  In the variable device 140 described above, when the oil is supplied from the oil tank 142 to the communication portion 32b through the oil flow path 144, the piston drive mechanism 128 moves the piston 126 to the left in FIG. (Equivalent to an example of “first direction”). Further, when the oil in the communication portion 32b is collected in the oil tank 142 via the oil flow path 144, the piston drive mechanism 128 moves the piston 126 to the right in FIG. 8 (“second direction” according to the present invention). Equivalent to one example). Therefore, the variable device 140 also controls the position (horizontal position) of the piston 126 in the oil tank 142 to adjust the oil surface height Hc in the crank chamber 32 (the passage cross-sectional area of the communicating portion 32b). can do.

(Sixth Modification)
FIG. 9 is a schematic diagram for explaining the configuration of a passage sectional area changing device 150 according to a sixth modification example of the first embodiment of the present invention. The variable device 150 shown in FIG. 9 includes an oil tank 152, an oil flow path 154, a volume adjuster 156, and a volume adjuster drive mechanism 158. The oil tank 152, the volume adjuster 156, and the volume adjuster drive mechanism 158 may be mounted on the internal combustion engine 10 via a support member (not shown), or may be mounted on the vehicle body.

  The oil tank 152 has the same oil capacity as the oil tank 42, and is fixed to the support member. The oil flow path 154 connects the oil tank 152 (for example, its bottom portion) and the communication portion 32b (for example, its bottom portion). The volume adjuster 156 is arranged in the oil tank 152.

  The volume adjuster drive mechanism 158 includes a rope 158a, an electric motor 158b, a pulley 158c, and a counterweight 158d for moving the volume adjuster 156 in and out of the oil. One end of the rope 158a wound around the pulley 158c is fixed to the upper part of the volume adjusting body 156, and the other end is fixed to the upper part of the counterweight 158d. The pulley 158c is rotationally driven by the electric motor 158b. When the pulley 158c is rotated by the electric motor 158b, the volume adjuster 156 moves up and down in the oil tank 152. Therefore, the volume adjusting body drive mechanism 158 can be used to take the volume adjusting body 156 in and out of the oil. Further, the variable device 150 includes a gas flow channel 159 similar to the gas flow channel 132 shown in FIG. 7.

  According to the variable device 150 configured as described above, when the volume adjusting body 156 enters oil, the oil level height Ht in the oil tank 152 rises. Accordingly, the oil pressure at the bottom of the oil tank 152 becomes higher than the oil pressure at the bottom of the communication portion 32b, so that the oil in the oil tank 152 flows into the communication portion 32b so as to eliminate this oil pressure difference. As a result, the oil level height Hc in the crank chamber 32 increases. When the volume adjuster 156 is taken out from the oil, the oil pressure at the bottom of the oil tank 152 decreases, contrary to the above, so that the oil in the communication portion 32b flows into the oil tank 152.

  According to the variable device 150 described above, the volume adjusting body drive mechanism 158 is used to increase the volume of the volume adjusting body 156 in the oil so that the oil is supplied from the oil tank 152 to the communicating portion 32b via the oil flow path 154. The amount of oil can be increased. Further, the volume of the volume adjuster 156 in the oil is reduced by using the volume adjuster drive mechanism 158 to increase the amount of oil recovered from the communication portion 32b into the oil tank 152 via the oil flow path 154. You can Therefore, by controlling the volume of the volume adjuster 156 in the oil, the oil level height Hc in the crank chamber 32 (the passage cross-sectional area of the communication portion 32b) can be adjusted. In addition, by appropriately selecting the size of the volume adjuster 156, the oil level height Hc can be adjusted with a desired adjustment width.

(Seventh modification)
FIG. 10 is a schematic diagram for explaining the configuration of a passage sectional area changing device 222 according to a seventh modified example of the first embodiment of the present invention. The internal combustion engine 220 shown in FIG. 10 differs from the internal combustion engine 10 shown in FIG. 1 in that a passage cross sectional area changing device 222 is provided instead of the passage cross sectional area changing device 40. Although not described in the first embodiment, an oil pan chamber 224 that communicates with the crank chamber 32 (communication portion 32b) exists below the crank chamber 32. More specifically, the oil is stored in the oil pan chamber 224.

  The variable device 222 is configured so that the volume of the oil pan chamber 224 can be changed. Specifically, the variable device 222 includes a volume adjusting body (for example, a volume adjusting rod) 226 that is directly put in and taken out from the oil pan chamber 224, and a volume adjusting body drive mechanism 228 that drives the volume adjusting body 226. The volume adjusting body drive mechanism 228 uses, as an example, a screw mechanism similar to the tank position adjusting mechanism 46 (see FIG. 2) for adjusting the horizontal position of the volume adjusting body 226, and uses the shaft 48 and the electric motor. 50 and. The electric motor 50 is fixed to the internal combustion engine 220 via a support member 230. A seal member 232 seals between the side surface of the volume adjuster 226 and the wall surface of the oil pan 30 facing the side surface.

  FIG. 10 shows a fully closed state in which the passage cross-sectional area of the communication portion 32b becomes minimum (zero) due to the oil level height Hc being higher than the upper end of the vent hole 38. The insertion amount of the volume adjusting body 226 into the oil pan chamber 224 is the largest in this fully closed state. The variable device 222 changes the volume of the oil pan chamber 224 (volume of the space capable of storing oil) by reducing the insertion amount of the volume adjusting body 226 in the fully closed state. Then, when the insertion amount is reduced most, the oil surface height Hc becomes the minimum and the passage cross-sectional area becomes the minimum (fully open state shown in FIG. 10). As described above, according to the variable device 222, the passage cross-sectional area of the communication portion 32b can be switched by changing the volume of the oil pan chamber 224 to change the oil level height Hc.

(8th modification)
FIG. 11 is a schematic diagram for explaining the configuration of the passage cross-sectional area changing device 240 according to the eighth modification example of the first embodiment of the present invention. The “passage cross-section area varying device” that changes the volume of the oil pan chamber 224 to change the oil level height Hc in the crank chamber 32 in order to switch the passage cross-sectional area of the communication portion 32b is the variable device 222 shown in FIG. Instead, for example, the variable device 240 shown in FIG. 11 may be configured.

  Specifically, the variable device 240 shown in FIG. 11 includes an airbag 242, an air pump 244, and an air relief mechanism 246. The airbag 242 is arranged in the oil pan chamber 224. The air pump 244 is configured to be capable of pumping air (for example, outside air) into the airbag 242 via the air supply flow path 248. The air relief mechanism 246 is configured to be able to discharge the air in the airbag 242 to the outside via the air discharge flow path 252 by opening the relief valve 250.

  According to the variable device 240, air is supplied to the airbag 242 by the air pump 244 to inflate the airbag 242, whereby the volume of the oil pan chamber 224 can be reduced and the oil level height Hc can be lowered. On the other hand, the air relief mechanism 246 is operated to discharge the air from the airbag 242 to deflate the airbag 242, whereby the volume of the oil pan chamber 224 can be increased and the oil level height Hc can be increased. As described above, also by the variable device 240, the passage cross-sectional area of the communication portion 32b can be switched by changing the volume of the oil pan chamber 224 and changing the oil level height Hc.

2. Embodiment 2
Next, with reference to FIGS. 12 to 15, a second embodiment of the present invention and a control example related thereto will be described.

2-1. Configuration Example of Vehicle System FIG. 12 is a schematic diagram for explaining a configuration example of the vehicle system 160 according to the second embodiment of the present invention. A vehicle system 160 shown in FIG. 12 serves as a vehicle power source, together with internal combustion engine 10 according to the first embodiment, a first motor generator 162 (hereinafter, abbreviated as “MG1”) and a second motor generator 164 (hereinafter, “ MG2 "). That is, the vehicle system 160 is applied to a hybrid vehicle as an example.

  The internal combustion engine 10 is provided with the following configuration in addition to the passage cross sectional area varying device 40. That is, the internal combustion engine 10 is, for example, a spark ignition type engine. However, the internal combustion engine to which the present invention is applied may be a compression ignition type engine, and the number of cylinders and the arrangement of the cylinders are not particularly limited. The internal combustion engine 10 includes a fuel injection valve 166 and an ignition device 168 (only a spark plug is shown). The fuel injection valve 166 is arranged in each cylinder 12 and injects fuel directly into the cylinder 12, for example. The ignition device 168 ignites an air-fuel mixture in the cylinder 12 by using an ignition plug arranged in each cylinder 12.

  An air flow sensor 172 that outputs a signal according to the flow rate of the air taken into the intake passage 170 is provided near the inlet of the intake passage 170 of the internal combustion engine 10. An electronically controlled throttle valve 174 is arranged in the intake passage 170 on the downstream side of the air flow sensor 172. Further, the internal combustion engine 10 includes a crank angle sensor 176. The crank angle sensor 176 outputs a signal according to the crank angle.

  Both MG1 and MG2 are electric motors capable of generating electricity. That is, MG1 and MG2 are AC synchronous motor generators that have both a function as a motor that outputs torque with supplied electric power and a function as a generator that converts input mechanical power into electric power. In vehicle system 160 shown in FIG. 12, MG1 is mainly used as a generator, and MG2 is mainly used as a motor.

  Internal combustion engine 10, MG1 and MG2 are connected to wheels 182 via power split mechanism 178 and reduction mechanism 180. Power split device 178 is, for example, a planetary gear unit, and splits the torque output from internal combustion engine 10 into MG1 and wheels 182. More specifically, in power split device 178, the sun gear is connected to the rotary shaft of MG1, the carrier is connected to crankshaft 20 of internal combustion engine 10, and the ring gear is connected to the rotary shaft of MG2. The torque output from the internal combustion engine 10 or the torque output from the MG2 is transmitted to the wheels 182 via the speed reduction mechanism 180. MG1 regenerates electric power with the torque supplied from internal combustion engine 10 via power split device 178.

  The MG1 and MG2 exchange power with the battery 186 via the power control unit (PCU) 184. PCU 184 includes an inverter, converts the electric power stored in battery 186 from direct current to alternating current and supplies it to MG2, and converts the electric power generated by MG1 from alternating current to direct current and stores it in battery 186. Therefore, battery 186 is charged by the electric power generated in MG1 and discharged by the electric power consumed in MG2. An SOC sensor 188 for detecting the state of charge (SOC) of the battery 186 is attached to the battery 186.

  In vehicle system 160 configured as described above, regenerative braking can be performed using MG2 during deceleration of the hybrid vehicle that is performed while the fuel supply to internal combustion engine 10 is stopped. More specifically, by controlling the PCU 184 so that the power generation load (regenerative load) is applied to the MG 2 during deceleration, the MG 2 can be rotationally driven by the wheels 182. As a result, the vehicle kinetic energy can be recovered during deceleration and converted into electric power. That is, MG2 and PCU184 are equivalent to an example of the "regenerative braking device" concerning the present invention. The battery 186 also stores the electric power obtained by the regenerative braking device. According to the vehicle system 160, at the time of deceleration performed while the fuel supply to the internal combustion engine 10 is stopped, the rotation of the internal combustion engine 10 is not stopped by controlling the energization of the MG1. By the rotation of the wheels (driving wheels) 182, it is possible to obtain a state in which the internal combustion engine 10 is driven to rotate (motoring state). During deceleration (braking) of the vehicle described below, it is assumed that the internal combustion engine 10 is in the motoring state.

  The vehicle system 160 of the present embodiment includes a control device 190 for controlling a power train including the internal combustion engine 10, MG1 and MG2. The control device 190 is an electronic control unit (ECU) having a processor 190a and a memory 190b. More specifically, in the present embodiment, it is assumed that the control device 190 also comprehensively includes the functions of the control device 60 shown in FIG. However, the number of ECUs that configure control device 190 is not particularly limited, and for example, an ECU that controls internal combustion engine 10 and an ECU that controls MG1 and MG2 may be individually provided.

  In addition to the air flow sensor 172, the crank angle sensor 176, and the SOC sensor 188, the control device 190 is electrically connected with various sensors used for controlling the power train, such as an accelerator position sensor 192 and a brake position sensor 194. There is. The accelerator position sensor 192 and the brake position sensor 194 respectively output signals corresponding to the depression amounts of the accelerator pedal and the brake pedal of the hybrid vehicle. The control device 190 can calculate the engine rotation speed NE using the signal from the crank angle sensor 176.

  Further, the control device 190 is electrically connected to various actuators for controlling the power train, such as the passage cross-sectional area varying device 40, the fuel injection valve 166, the ignition device 168, the throttle valve 174, MG1 and MG2 described above. ing.

  Further, the vehicle system 160 includes a hydraulic brake device (not shown). The hydraulic brake device includes a brake actuator 196. The brake actuator 196 can adjust the brake hydraulic pressure applied to each wheel 182 by controlling various electromagnetic valves provided in the hydraulic circuit of the hydraulic brake device. Therefore, the control device 190 controls the braking torque applied to each wheel 182 by the hydraulic brake device by adjusting the brake hydraulic pressure by the brake actuator 196, and as a result, the braking force (braking force) of the vehicle is increased. Can be controlled.

2-2. Control during vehicle braking 2-2-1. Fuel Cut Processing In the vehicle system 160 of the present embodiment, the control device 190 causes the fuel injection for each cylinder when the vehicle is braked (in the present embodiment, the accelerator pedal is turned off). A "fuel cut process" for controlling the fuel injection valve 166 to stop is executed. More specifically, the fuel cut process is executed on the condition that a predetermined execution condition (the engine rotation speed NE is a predetermined value or more) is satisfied. During deceleration of the vehicle after the fuel cut processing is executed, the internal combustion engine 10 is driven by the rotation of the wheels (driving wheels) 182 to be in a motoring state. Therefore, the internal combustion engine 10 generates engine braking torque (engine braking force).

2-2-2. Utilization and Issues of Regenerative Brake The vehicle system 160 includes the MG2 and the PCU 184 having the function as the above-described regenerative brake device. Therefore, the regenerative brake can be used for braking the vehicle together with the hydraulic brake using the hydraulic brake device described above (corresponding to an example of the "regenerative braking process" according to the present invention). By charging the battery 186 using the electric power obtained by the regenerative braking, it is possible to reduce the power of the internal combustion engine 10 used for generating the electric power consumed by the MG2. Therefore, the fuel economy of the internal combustion engine 10 can be improved.

  The braking torque that acts on the wheels 182 when the regenerative brake is used is the sum of the engine braking torque generated by the internal combustion engine 10 during the fuel cut operation (motoring) and the regenerative braking torque by the regeneration using the MG2. However, the regenerative braking torque cannot always be used while the vehicle is traveling. Specifically, if the battery 186 that stores the electric power generated by the regenerative brake is fully charged, the regenerative brake cannot be charged. As a result, since the regenerative brake cannot be used, the regenerative braking torque cannot be obtained. As a result, the deceleration of the vehicle is lower than that in the non-fully charged state, and the driver of the vehicle may feel uncomfortable. Further, in the fully charged state where the regenerative brake cannot be used, it may be necessary to increase the size of the hydraulic brake in order to secure the braking torque equivalent to that in the non-fully charged state. The “fully charged state” of the battery 186 here means a state in which the SOC of the battery 186 has reached its upper limit value (more specifically, the upper limit value of SOC within a predetermined use range).

2-2-3. Outline of Control According to Second Embodiment In the present embodiment, the control device 190 controls the fuel cut process and the regenerative brake process described above when the battery 186 is in a non-fully charged state when the accelerator pedal is turned off. And execute. On the other hand, in the case where the battery 186 is in the “fully charged state” when the accelerator pedal is turned off, the control device 190 takes into consideration the above-mentioned problems, together with the fuel cut processing described above, and the “path disconnection” described below. Area reduction processing ".

  As described above, when the oil level height Hc in the crank chamber 32 is increased to reduce the passage cross-sectional area of the communication portion 32b, the engine braking torque (engine braking force) can be increased due to the increase in pumping loss. . In the passage cross-sectional area reduction process, the variable device 40 is controlled so that the passage cross-sectional area becomes smaller than that in the case where the accelerator pedal is turned off under the non-fully charged state. As a result, instead of the regenerative braking torque that cannot be used in the fully charged state, the engine braking torque that increases due to the decrease in the passage cross-sectional area can be used.

2-2-4. Processing of Control Device FIG. 13 is a flowchart showing a routine of processing relating to control during vehicle braking according to the second embodiment of the present invention. The control device 190 repeatedly executes the processing of this routine.

  In the routine shown in FIG. 13, first, the control device 190 uses the accelerator position sensor 192 to determine whether or not the accelerator pedal is turned off (step S100). As a result, when the determination result of step S100 is negative (that is, when the vehicle is not being braked), the process proceeds to step S102. In step S102, the control device 190 controls the variable device 40 so that the fully opened state (maximum passage sectional area) shown in FIG. Then, the processing cycle of this time is ended.

  On the other hand, when the determination result of step S100 is affirmative, the control device 190 executes the above-described fuel cut processing (step S104). More specifically, the fuel cut process is executed on condition that the engine speed NE is equal to or higher than a predetermined value when the accelerator pedal is turned off.

  Next, the control device 190 calculates the required braking force (step S106). The required braking force here is the braking force required of the vehicle by the driver. The required braking force is calculated to increase as the amount of depression of the brake pedal detected by the brake position sensor 194 increases. The amount of depression of the brake pedal used for this calculation includes zero. Therefore, the case where the accelerator pedal is turned off and the brake pedal is not depressed is included when the vehicle is being braked which is the control target of this routine. The required braking force may be determined based on the depression speed of the brake pedal in addition to the depression amount.

  Next, the control device 190 determines whether or not the regenerative braking force is equal to or greater than the required braking force calculated in step S106 (step S108). The regenerative braking force used for this determination is a braking force (value obtained in advance) that can be generated by the regenerative braking.

  If the determination result of step S108 is negative (regenerative braking force <required braking force), that is, if it can be determined that the required braking force cannot be satisfied only by the regenerative braking force, the process proceeds to step S110. In step S110, the control device 190 executes cooperative brake control that uses a hydraulic brake together with a regenerative brake in order to satisfy the required braking force. Since the contents of such cooperative brake control are known, detailed description thereof will be omitted here. When the process proceeds to step S110 in this way, the communication portion 32b is in the fully open state shown in FIG. 3 (A).

  On the other hand, if the determination result of step S108 is affirmative (regenerative braking force ≧ requested braking force), the process proceeds to step S112. In step S112, control device 190 determines whether or not battery 186 is fully charged. More specifically, it is determined whether the SOC of the battery 186 is equal to or higher than the above upper limit value (for example, 90%).

  When the determination result of step S112 is negative (that is, when the battery 186 is in the non-fully charged state), the process proceeds to step S114. In step S114, the control device 190 executes regenerative braking so as to satisfy the required braking force.

  On the other hand, when the determination result of step S112 is affirmative (that is, when the battery 186 is in the fully charged state), the process proceeds to step S116. In step S116, the control device 190 controls the variable device 40 so that the half open state shown in FIG. Then, a process progresses to step S118.

  In step S118, the control device 190 determines whether the required braking force calculated in step S106 is greater than or equal to the braking force. This braking force can be calculated (estimated) using the following method, for example. That is, the memory 190b pre-stores a map as shown in FIG. 17 described later (relationship between the braking force of the vehicle, the passage cross-sectional area of the communication portion 32b, and the engine rotation speed NE). . The controller 190 calculates the estimated braking force according to the passage cross-sectional area and the engine rotation speed NE from such a map.

  If the determination result of step S118 is negative (request braking force <brake force), that is, if it can be determined that the required braking force can be satisfied by setting the communication portion 32b in the half-opened state, the current processing cycle ends. To be done.

  On the other hand, if the determination result of step S118 is affirmative (required braking force ≧ braking force), that is, if it is determined that merely setting the communication portion 32b in the half-open state is insufficient to satisfy the required braking force. , The process proceeds to step S120. In step S120, the control device 190 controls the variable device 40 so that the fully closed state shown in FIG. Then, a process progresses to step S122.

  In step S122, the control device 190 determines whether the required braking force is equal to or greater than the braking force, as in the process of step S118. As a result, if the determination result of step S122 is negative, that is, if it can be determined that the required braking force can be satisfied by fully closing the communication portion 32b, the current processing cycle is ended.

  On the other hand, when the determination result of step S122 is affirmative (required braking force ≧ braking force), that is, when it can be determined that the required braking force is insufficient even when the communication portion 32b is fully closed. The process proceeds to step S124. In step S124, the control device 190 executes hydraulic brake control. According to this hydraulic brake control, the control device 190 controls the brake actuator (not shown) so that the braking torque applied to the wheels 182 by the hydraulic brake device described above increases.

  It should be noted that, after the braking of the vehicle is completed, the variable device 40 is controlled so that the communication portion 32b is fully opened.

2-3. Effect According to the process of the routine shown in FIG. 13 described above, when the vehicle is braked when the battery 186 is in the fully charged state (accelerator pedal is off), the vehicle is braked under the non-fully charged state. The passage cross-sectional area of the communication portion 32b is reduced as compared with the case (accelerator pedal off). As a result, in the fully charged state where the regenerative brake cannot be used, the engine braking torque (engine braking force) can be increased by utilizing the decrease in the passage cross-sectional area due to the increase in the oil level height Hc in the crank chamber 32. As a result, a decrease in the total braking torque of the vehicle due to the inability to use the regenerative brake can be suppressed (supplemented) by an increase in the engine braking torque.

  More specifically, according to the processing of the above routine, when the battery 186 is in the fully charged state, first, the passage cross-sectional area is reduced so that the communication portion 32b is in the half-opened state. When the braking force is insufficient with respect to the required braking force under the half-open state, the communication section 32b is controlled to the fully closed state by further reducing the passage cross-sectional area. That is, according to the passage cross-sectional area reduction processing of the present embodiment, the greater the required braking force, the more the passage cross-sectional area is reduced. By changing the passage cross-sectional area according to the required braking force of the vehicle in this way, the engine braking torque can be increased by an appropriate amount according to the required braking force in the fully charged state.

2-4. Another control example related to the second embodiment 2-4-1. Coordinated Control with Hydraulic Brake FIG. 14 is a diagram for explaining coordinated control with an engine brake and a hydraulic brake that utilizes a change in passage cross-sectional area. In the second embodiment described above, variable device 40 is controlled so that the passage cross-sectional area decreases when battery 186 is in a fully charged state during vehicle braking. It takes some time to change the oil level height Hc in the crank chamber 32 to change the passage cross-sectional area. Therefore, the following cooperative control may be additionally executed.

  The time point t0 in FIG. 14 corresponds to the braking start time point. According to this cooperative control, the brake actuator is configured so that the hydraulic brake having relatively excellent responsiveness is used in the initial stage of braking, that is, in the period from the start of braking to the time t1 when the actual braking force reaches the required braking force. 196 is controlled. As a result, the braking force can be secured with high response in the initial stage of braking.

  The reduction of the passage cross-sectional area by the variable device 40 is started at the time t1 when the actual braking force reaches the required braking force. In the subsequent period, the braking force of the hydraulic brake is reduced according to the increase of the braking force due to the decrease of the passage cross-sectional area. More specifically, the characteristic that the braking force increases with the passage of time due to the decrease in the passage cross-sectional area can be understood by conducting experiments in advance. Therefore, after the time point t1, the braking force of the hydraulic brake is reduced over time, for example, in consideration of the above characteristics.

  Time point t2 corresponds to the time point when the replacement of the hydraulic brake with the engine brake utilizing the decrease in the passage cross-sectional area is completed. When changing the passage cross-sectional area, such cooperative control may be executed.

2-4-2. Another Control Example During Vehicle Braking The engine brake control of the second embodiment described above is applicable to the following vehicle system, for example, instead of the vehicle system 160 shown in FIG. The vehicle system mentioned here includes a stepped automatic transmission in addition to the internal combustion engine 10, the regenerative braking device, and the battery shown in FIG. When the vehicle system including the stepped automatic transmission is adopted as described above, the following routine shown in FIG. 15 may be executed.

  FIG. 15 is a flowchart showing a processing routine relating to another control example during vehicle braking according to the present invention. The processing of steps S100 to S124 in the routine shown in FIG. 15 is as described in the first embodiment.

  In the routine shown in FIG. 15, if the determination result of step S122 is affirmative, that is, if it is possible to determine that the communication portion 32b is in the fully closed state but is insufficient to satisfy the required braking force, the processing is performed. It proceeds to step S200. In step S200, the control device 190 executes engine rotation speed increase processing. The engine rotation speed increasing process is executed by, for example, performing an operation (shift down) for lowering the shift speed of the stepped automatic transmission by one. As a result, the engine rotation speed NE increases, so that the engine braking force can be increased.

  Then, a process progresses to step S202. In step S202, the control device 190 determines whether the required braking force is equal to or greater than the braking force, as in the processes of steps S118 and S122. As a result, when the determination result of step S202 is negative, that is, when it is determined that the required braking force can be satisfied by the increase of the engine rotation speed NE, the current processing cycle is ended. In a vehicle system including a stepped automatic transmission, the braking torque of the wheels 182 derived from the engine brake also changes depending on the gear position. Therefore, in this routine applied to this vehicle system, in calculating (estimating) the braking force by the processing of steps S118, S122, and 202, the gear shift stage is considered together with the passage cross-sectional area of the communication portion 32b and the engine rotation speed NE. May be.

  On the other hand, if the determination result of step S202 is affirmative (required braking force ≧ brake force), that is, if it can be determined that the required braking force is not satisfied even after the engine speed NE is increased, the process proceeds to step. It proceeds to S204. In step S204, control device 190 determines whether engine rotation speed NE is higher than a threshold value. This threshold value corresponds to the upper limit value of the engine rotation speed NE that can further reduce the shift speed. Note that the method of changing the engine rotation speed NE during vehicle braking differs depending on the inclination angle of the road surface (for example, whether the road is a flat road or a downhill). Therefore, the number of shift stages that can be lowered for increasing the engine braking force varies depending on the inclination angle of the road surface. Therefore, this threshold value may be changed according to the inclination angle of the road surface during vehicle braking.

  If the determination result in step 204 is negative (engine speed NE ≦ threshold value), the process proceeds to step S202, and the shift speed is further reduced by one. On the other hand, if the result of this determination is affirmative (engine speed NE> threshold), that is, if it is possible to determine that the required braking force is not satisfied despite performing the downshift operation as much as possible, The hydraulic brake control is executed by the process of S124.

  According to the processing of the routine shown in FIG. 15 to which the above-described engine rotation speed increase processing is added, the engine rotation speed NE is increased as necessary, so that the effect of increasing the engine braking force by utilizing the decrease in the passage cross-sectional area is achieved. You will be able to withdraw more effectively.

3. Embodiment 3
Next, a third embodiment of the present invention will be described with reference to FIGS. 16 and 17. In the following description, it is assumed that vehicle system 160 shown in FIG. 12 is used as an example of the vehicle system according to the third embodiment.

3-1. Control During Vehicle Braking In the second embodiment described above, when the battery 186 is fully charged during vehicle braking, the passage cross-sectional area is selected so that either the half-open state or the fully-closed state of the communication portion 32b is selected. Can be switched to two stages. On the other hand, in the present embodiment, when the battery 186 is in a fully charged state, the passage cross-sectional area is continuously changed (at least in three steps or more) according to the required braking force.

3-1-1. Process of control device relating to control during vehicle braking FIG. 16 is a flowchart showing a routine of a process relating to control during vehicle braking according to the third embodiment of the present invention. The processes of steps S100 to S112, S122, and S124 in the routine shown in FIG. 16 are as described in the first embodiment.

  In the routine shown in FIG. 16, after it is determined in step S112 that the battery 186 is fully charged, the process proceeds to step S300. In step S300, the control device 190 calculates the target passage sectional area according to the required braking force calculated in step S106.

  FIG. 17 is a graph showing the relationship between the vehicle braking force, the passage cross-sectional area of the communication portion 32b, and the engine rotation speed NE. As shown in FIG. 17, the braking force of the vehicle becomes larger as the passage cross-sectional area becomes smaller under the same engine rotation speed NE. Further, this braking force becomes larger as the engine speed NE is higher under the same passage sectional area. As described above, the memory 190b stores the relationship as shown in FIG. 17 as a map. In step S300, the control device 190 calculates the target passage cross-sectional area according to the current required braking force and the engine rotation speed NE from such a map. Then, a process progresses to step S302.

  In step S302, the control device 190 controls the variable device 40 so that the target passage cross-sectional area calculated in step S300 is obtained. More specifically, the control position of the oil tank 42 required to realize the oil level height Hc corresponding to each selectable target passage cross-sectional area has been acquired in advance by experiments or the like. Then, such a control position is stored in the memory 190b of the control device 190. In step S302, the control device 190 controls the variable device 40 (tank position adjusting mechanism 46) so that the oil tank 42 is displaced toward the control position that achieves the oil level height Hc corresponding to the calculated target passage sectional area. ) Control. Then, a process progresses to step S122.

3-2. Effect As described above, according to the control of the present embodiment, when the battery 186 is in a fully charged state during vehicle braking, the passage cross-sectional area is continuously changed according to the required braking force. As a result, in a situation where the regenerative brake cannot be used because the battery 186 is fully charged, the engine braking force according to the required braking force can be more appropriately exerted by using the change of the passage cross-sectional area.

4. Embodiment 4
Next, a fourth embodiment of the present invention will be described with reference to FIGS. 18 and 19.

4-1. Configuration Example of Internal Combustion Engine FIG. 18 is a diagram schematically showing a configuration example of an internal combustion engine 200 according to Embodiment 4 of the present invention. Hereinafter, the configuration of the internal combustion engine 200 will be described focusing on the differences from the internal combustion engine 10 shown in FIG.

  As shown in FIG. 18, the internal combustion engine 200 is provided with a shutter device 202 corresponding to another example of the passage sectional area varying device, instead of the passage sectional area varying device 40. The shutter device 202 is configured to be able to change the opening area of the ventilation holes 38 provided in each of the partition walls 34. In the present embodiment, by changing the opening area of the ventilation hole 38 by the shutter device 202, the passage cross-sectional area of the communication portion 32b can be switched in three stages. As described above, the passage cross-sectional area of the communication portion 32b that is a variable target in the present embodiment is the opening area of the ventilation hole 38.

  19A and 19B are schematic views for explaining an example of a specific configuration of the shutter device 202 shown in FIG. More specifically, FIG. 19 (A) is a view of the configuration around two adjacent cylinders 12 as viewed from the cylinder axis direction. FIG. 19B is an enlarged view of the part B in FIG.

  As shown in FIG. 19A, the shutter device 202 includes a shutter valve 204, a link mechanism 206, and an electric motor 208. The shutter valve 204 is engaged with the guide groove 210. As shown in FIG. 19B, the guide groove 210 is formed on each of the upper and lower peripheral surfaces of the vent hole 38 so as to extend in a direction perpendicular to the cylinder axis direction. The shutter device 202 reciprocates the shutter valve 204 guided by the guide groove 210. As a result, the opening area of the ventilation hole 38 is changed by the shutter valve 204.

  More specifically, the link mechanism 206 is attached to the side surface of the cylinder block 14. The link mechanism 206 includes a rod 212 whose one end is fixed to the shutter valve 204. The cylinder block 14 is formed with a communication hole 214 that communicates the side surface with the ventilation hole 38, and the rod 212 is housed in the communication hole 214. The link mechanism 206 is also connected to a shutter valve 204 arranged in the cylinder 12, which is not shown in FIG. 19A. Therefore, according to the link mechanism 206, the shutter valve 204 (not shown) also operates in conjunction with the shutter valve 204 shown in FIG.

  The link mechanism 206 is configured such that when the electric motor 208 is rotated within a predetermined angle range, the rod 212 is displaced and the shutter valve 204 is opened and closed. In FIG. 19A, the control position (fully closed position) of the link mechanism 206 when the shutter valve 204 fully closes the ventilation hole 38 is shown by a solid line.

  The control position of the link mechanism 206 by the electric motor 208 includes the above fully closed position, and a half open position and a fully open position indicated by broken lines in the figure. At the half-open position, a part of the shutter valve 204 retreats from the ventilation hole 38 to the communication hole 214, and as a result, the ventilation hole 38 is in the half-opened state. At the fully open position, the shutter valve 204 is entirely retracted from the vent hole 38, and as a result, the vent hole 38 is fully opened. A seal member 216 seals between the shutter valve 204 and the communication hole 214 in order to prevent gas from leaking from the inside of the ventilation hole 38 to the outside of the cylinder block 14.

  According to the shutter device 202 described above, the opening area of the ventilation hole 38 can be switched in three stages by changing the control position of the link mechanism 206 among the fully closed position, the half open position, and the fully open position by the electric motor 208. it can. As a result, the passage cross-sectional area of the communication portion 32b can be switched in three stages.

4-2. Effect As described above, the internal combustion engine 200 including the shutter device 202 can also switch the passage cross-sectional area of the communication portion 32b in three stages. Therefore, the engine braking force can be finely adjusted as compared with an engine braking device that can switch the open state of the vent hole in two steps.

(Example of switching the passage cross-sectional area to four or more levels)
In addition, in the internal combustion engine 200 including the shutter device 202, the number of control positions of the link mechanism 206 may be increased more than three in the example shown in FIG. This makes it possible to switch the passage cross-sectional area of the communication portion 32b in four or more steps. As a result, the engine braking force can be adjusted more finely.

4-3. Control Example of Vehicle System Utilizing Internal Combustion Engine of Fourth Embodiment The vehicle system 160 according to the second embodiment described above includes the internal combustion engine 200 according to the fourth embodiment instead of the internal combustion engine 10 according to the first embodiment. You may prepare. Then, the control during vehicle braking according to the second embodiment (see FIG. 13) may be executed for the vehicle system thus modified. Specifically, a routine similar to the routine shown in FIG. 13 may be executed by the control device 190 for the vehicle system. This corresponds to that the “passage cross-section reduction process” similar to the “passage cross-section reduction process” according to the second embodiment is executed using the shutter device 202.

  Further, a routine similar to the routine shown in FIG. 16 according to the third embodiment described above may be executed by control device 190 for the vehicle system modified as described above. Thus, the shutter device 202 can be controlled so that the opening area of the ventilation hole 38 becomes smaller as the required vehicle braking force increases.

5. Other Embodiments (Other Examples of Vehicle System)
In the above-described Embodiments 2 and 3, the vehicle system 160 in which the regenerative braking process is performed when the accelerator pedal is turned off (depression amount is zero) when the battery 186 is in the non-fully charged state has been described. However, in another example of the vehicle system to which the control according to the present invention can be applied, the engine brake of the internal combustion engine can be used, and the accelerator pedal is in the off position (the depression amount when the battery is not fully charged). The regenerative braking process may be performed even when the vehicle is stepped back to a position other than (zero). Then, in such a vehicle system, the passage cross-sectional area reduction process may be executed when the accelerator pedal is stepped back to the other position when the battery is fully charged.

  Further, the vehicle system to which the control according to the present invention can be applied can use the engine brake of the internal combustion engine, and the regenerative braking device that recovers the vehicle kinetic energy during deceleration and converts it into electric power and the battery that stores the electric power. A hybrid vehicle system of a system other than the system shown in FIG. Further, another example of the vehicle system is a vehicle system that includes only an internal combustion engine as a power source of the vehicle instead of the hybrid vehicle system and is capable of operating a regenerative brake by using an alternator mounted on the internal combustion engine. May be

  The examples and other modifications described in the above embodiments may be appropriately combined within a possible range other than the explicit combination, and various modifications may be made without departing from the spirit of the present invention. You may.

10, 200, 220 Internal combustion engine 12 Cylinder 14 Cylinder block 18 Connecting rod 20 Crankshaft 22 Counterweight 28 Crankcase 30 Oil pan 32 Crank chamber 32b Crank chamber communication part 34 Partition wall 38 Vent holes 40, 70, 80, 100, 120, 140, 150, 222, 240 passage cross-sectional area changing devices 42, 102, 122, 142, 152 oil tank 44 oil hoses 46, 72, 82 tank position adjusting mechanisms 60, 190 control device 104 oil supply flow passage 106 oil pump 108 oil Return flow passage 110 Valves 124, 144, 154 Oil flow passage 126 Piston 128 Piston drive mechanism 156 Volume adjuster 158, 228 Volume adjuster drive mechanism 160 Vehicle system 162 First motor generator (MG1)
164 Second motor generator (MG2)
166 Fuel injection valve 176 Crank angle sensor 182 Wheel 184 Power control unit (PCU)
186 Battery 188 SOC sensor 192 Accelerator position sensor 194 Brake position sensor 196 Brake actuator 202 Shutter device (passage area variable device)
204 shutter valve 224 oil pan chamber 242 airbag 244 air pump 246 air relief mechanism

Claims (10)

A cylinder block having a partition wall formed to partition a plurality of cylinders into cylinders;
With a portion partitioned for each cylinder by the partition wall, a crank chamber having a communication portion that communicates between the plurality of cylinders,
A passage cross-sectional area varying device configured to be able to switch the passage cross-sectional area of the communication part in at least three stages in a direction perpendicular to the axial direction of the crankshaft,
An internal combustion engine comprising: The passage cross-sectional area changing device includes an oil tank that stores oil outside the crank chamber, and moves oil back and forth between the oil tank and the crank chamber to increase an oil level of the oil in the crank chamber. The internal combustion engine according to claim 1, wherein the passage cross-sectional area is switched by changing The passage cross-sectional area variable device,
A hose connecting the oil tank and the communication part,
A tank position adjusting mechanism for vertically moving the oil tank in the vertical direction,
The internal combustion engine according to claim 2, comprising: The passage cross-sectional area variable device,
An oil supply flow path connecting the oil tank and the communication part,
An oil pump which is arranged in the oil supply flow path and pressure-feeds the oil from the oil tank toward the communication portion;
An oil return flow path, one end of which is connected to the communication part, and the other end of which is lower than the one end in the vertical direction is connected to the oil tank,
A valve that is arranged in the oil return flow path and is configured to open when the oil in the communication section is collected in the oil tank;
The internal combustion engine according to claim 2, comprising: The passage cross-sectional area variable device,
An oil flow path connecting the oil tank and the communication part,
A piston arranged in the oil tank,
A piston drive mechanism for reciprocating the piston,
Including,
The passage cross-sectional area variable device,
When the piston is displaced in the first direction in the oil tank, oil is supplied from the oil tank to the communication portion via the oil flow path,
When the piston is displaced in a second direction opposite to the first direction, the oil in the communication section is collected into the oil tank via the oil flow path. The internal combustion engine according to claim 2. The passage cross-sectional area variable device,
An oil flow path connecting the oil tank and the communication part,
A volume adjuster arranged in the oil tank,
A volume adjuster drive mechanism for taking the volume adjuster in and out of oil,
Including,
The passage cross-sectional area variable device,
When increasing the volume of the volume adjuster in the oil using the volume adjuster drive mechanism, supplying oil from the oil tank to the communication portion via the oil flow path,
When the volume of the volume adjusting body in the oil is reduced by using the volume adjusting body drive mechanism, the oil in the communicating portion is collected into the oil tank via the oil flow path. The internal combustion engine according to claim 2, wherein: The internal combustion engine includes an oil pan chamber that communicates with the crank chamber and is formed below the crank chamber,
The passage cross-sectional area changing device is configured to change the passage cross-sectional area by changing the volume of the oil pan chamber to change the oil level of the oil in the crank chamber. The internal combustion engine according to claim 1, wherein The communication portion includes a vent hole formed in the partition wall so as to communicate between adjacent cylinders,
The passage cross-sectional area changing device includes a shutter device for changing the opening area of the ventilation hole, and the passage cross-sectional area can be switched by changing the opening area of the ventilation hole. The internal combustion engine according to claim 1. A vehicle system capable of using the engine brake of an internal combustion engine according to any one of claims 1 to 8,
The vehicle system is
The internal combustion engine;
A regenerative braking device that recovers vehicle kinetic energy and converts it into electric power during deceleration of a vehicle equipped with the internal combustion engine,
A battery for storing the electric power,
A control device for controlling the internal combustion engine and the regenerative braking device,
Equipped with
The control device is
When the vehicle is braked when the battery is in a non-fully charged state, a fuel cut process for controlling a fuel injection valve of the internal combustion engine so as to stop fuel injection, and the regenerative braking device are operated. Perform regenerative braking processing to
When the vehicle is braked when the battery is in a fully charged state, the passage cutoff is compared to when the vehicle is braked under the fuel cut process and the non-fully charged state. A vehicle system, comprising: performing a passage cross sectional area reduction process for controlling the passage cross sectional area changing device so as to reduce an area. The control device controls the passage cross-sectional area varying device such that, in the passage cross-sectional area reduction process, the passage cross-sectional area becomes smaller as the required braking force of the vehicle increases. The vehicle system according to.

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