JP2014181645A - Control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an internal combustion engine which curbs deterioration in responsiveness of a hydraulic type variable valve device.SOLUTION: A control device of an internal combustion engine comprises: a hydraulic type variable valve device which hydraulically changes an operating characteristic of either one of an intake valve or an exhaust valve of the internal combustion engine; a variable valve device which has a motor, a control shaft changing the operating characteristic of the other of the intake valve or the exhaust valve by moving in a shaft direction with the motor, a shaft bearing section supporting the control shaft with an opening to discharge oil to the control shaft provided thereon and a change section changing an opening rate of the opening in accordance with movement of the control shaft in the shaft direction; and a control section which moves the control shaft in a manner that allows the change section to reduce the opening rate when changing the operating characteristic of either one of the intake valve or the exhaust valve by supplying the oil to the hydraulic type variable valve device.

Description

  The present invention relates to a control device for an internal combustion engine.

  2. Description of the Related Art A hydraulic variable valve operating device that changes the operating characteristics of an engine valve by the action of hydraulic pressure is known. Patent Documents 1 to 4 disclose such an apparatus.

JP 2001-329819 A JP 2010-174703 A JP 2007-278277 A Japanese Patent Laid-Open No. 2004-301101

  When supplying oil to such a hydraulic variable valve device to change the operating characteristics of the engine valve, if oil is used in other parts, the hydraulic pressure supplied to the hydraulic variable valve device is secured. There is a possibility that the responsiveness deteriorates without being able to. In addition, when the supply of oil to the hydraulic variable valve device is stopped to change the operating characteristics of the engine valve, the responsiveness deteriorates even if the hydraulic pressure in the hydraulic variable valve device cannot be reduced early. There is a fear.

  Therefore, an object of the present invention is to provide a control device for an internal combustion engine that suppresses the deterioration of responsiveness of the hydraulic variable valve device.

  The object is to change the operating characteristics of one of the intake valve and the exhaust valve of the internal combustion engine by hydraulic pressure, a motor, and a motor, which is moved in the axial direction by the motor to move the intake valve and the exhaust valve. A control shaft for changing the operating characteristics of the other valve, an opening for discharging oil to the control shaft, a bearing portion for supporting the control shaft, and an opening ratio of the opening according to the axial movement of the control shaft A variable valve device including a change unit to be changed, and when changing the operating characteristics of one of the intake valve and the exhaust valve by supplying oil to the hydraulic variable valve device, the change unit causes the change This can be achieved by an internal combustion engine control device including a control unit that moves the control shaft so as to reduce the aperture ratio.

  The object is to change the operating characteristics of one of the intake valve and the exhaust valve of the internal combustion engine by hydraulic pressure, a motor, and a motor, which is moved in the axial direction by the motor to move the intake valve and the exhaust valve. A control shaft for changing the operating characteristics of the other valve, an opening for discharging oil to the control shaft, a bearing portion for supporting the control shaft, and an opening ratio of the opening according to the axial movement of the control shaft A variable valve device including a change unit to be changed, and the change in operating characteristics of one of the intake valve and the exhaust valve by stopping the supply of oil to the hydraulic variable valve device And a control unit that moves the control shaft so as to increase the aperture ratio by the unit.

  It is possible to provide a control device for an internal combustion engine that suppresses deterioration of responsiveness of the hydraulic variable valve operating device.

FIG. 1 is an explanatory diagram of the engine system of this embodiment. FIG. 2 is an external view of the exhaust side variable valve operating apparatus. FIG. 3 is an external view of the exhaust side variable valve operating apparatus. 4A and 4B are sectional views of the cam unit as seen from the axial direction. 5A and 5B are cross-sectional views showing the internal structure of the cam unit. 6A to 6C are explanatory diagrams of the lock of the cam lobe portion. 7A and 7B are explanatory diagrams of the lock of the cam lobe portion. FIG. 8 is an explanatory diagram of the intake side variable valve operating apparatus. 9A to 9C are explanatory views of the groove. FIG. 10 is a flowchart illustrating an example of control executed by the ECU. FIG. 11 is a map showing the oil pressure according to the oil temperature and the engine speed. FIG. 12 is a flowchart illustrating an example of control executed by the ECU.

  FIG. 1 is a schematic diagram of an engine system A according to the present embodiment. The engine system A shown in FIG. 1 includes an engine EN, and the engine EN has four cylinders 42 (only one is shown in FIG. 1). The number of cylinders 42 is not limited to four but may be plural. In the engine EN, air flowing through the intake passage 43 is filled in the combustion chamber 45, and fuel is injected by the in-cylinder fuel injection valve 44, thereby generating an air-fuel mixture. When the air-fuel mixture is ignited by the spark plug 46, the air-fuel mixture burns, the piston 47 reciprocates, and the crankshaft 48, which is the output shaft of the engine EN, is rotationally driven. Exhaust gas generated by the combustion in each combustion chamber 45 is discharged to the outside of the engine EN through the exhaust passage 49 and the like.

  The output adjustment of the engine EN is realized by driving a throttle valve 51 provided in the intake passage 43 by an actuator 52 and adjusting the opening of the throttle valve 51. The throttle opening degree is adjusted by driving the actuator 52 in accordance with the amount of depression of the accelerator pedal 53 operated by the driver.

  The engine EN is provided with an intake valve IV and an exhaust valve EV for each cylinder 42. The intake valve IV and the exhaust valve EV are operated by an intake side camshaft IS and an exhaust side camshaft ES, respectively, which are rotated by transmission of rotation of the crankshaft 48. By this operation, each intake valve IV opens and closes a connection portion between the combustion chamber 45 and the intake passage 43, and each exhaust valve EV opens and closes a connection portion between the combustion chamber 45 and the exhaust passage 49.

  The engine EN includes an intake side variable valve apparatus 1I that continuously changes the operating angle and maximum lift amount of the intake valve IV, and an exhaust side variable valve apparatus 1E that changes the operating angle of the exhaust valve EV in multiple stages by hydraulic pressure. And are provided. The intake side variable valve operating apparatus 1I changes the operation characteristics of the intake valve IV by a motor based on a command from the ECU 5, as will be described in detail later. The exhaust-side variable valve operating apparatus 1E changes the operating characteristics of the exhaust valve EV based on the pressure of the supplied oil, based on a command from the ECU 5. Specifically, the intake side variable valve apparatus 1I changes the operating angle and maximum lift amount of the intake valve IV, and the exhaust side variable valve apparatus 1E changes the phase, operating angle, and maximum lift amount of the exhaust valve EV. change. Here, the operating characteristics include at least one of the phase of the valves, the maximum lift amount, and the operating angle. Therefore, in this embodiment, the intake side variable valve operating apparatus 1I changes the operating angle and the maximum lift amount of the intake valve IV, but is not limited to this. For example, at least one of the operating angle and the maximum lift amount is changed. It may be changed. The intake-side variable valve operating apparatus 1I and the exhaust-side variable valve operating apparatus 1E change the operation characteristics of the intake valve IV and the exhaust valve EV provided for each of the plurality of cylinders 42. The intake side variable valve apparatus 1I is an example of a variable valve apparatus. The exhaust side variable valve operating apparatus 1E is an example of a hydraulic variable valve operating apparatus.

  The engine system A is provided with an oil pan 90 that stores hydraulic oil for driving the exhaust-side variable valve operating apparatus 1E. The oil stored in the oil pan 90 is supplied to the exhaust side variable valve operating apparatus 1E by the oil pump P. Further, the oil stored in the oil pan 90 is supplied to a bearing portion that supports the control shaft of the intake side variable valve operating apparatus 1I, which will be described in detail later. The supply amounts of these oils are controlled by oil control valves OCV1 and OCV2, respectively. The oil control valves OCV1 and OCV2 are electromagnetically driven flow control valves and are controlled by the ECU 5. The oil pump P is a mechanical type interlocked with the crankshaft 48 of the engine EN.

  The engine EN is provided with a crank angle sensor 71 that generates a pulse signal each time the crankshaft 48 rotates by a certain angle. An intake pressure sensor 74 for detecting the pressure of intake air is provided downstream of the throttle valve 51 in the intake passage 43. Further, an accelerator sensor 75 for detecting the amount of depression of the accelerator pedal 53 by the driver, a throttle sensor 76 for detecting the throttle opening degree, and a water temperature sensor 77 for detecting the temperature of the cooling water for cooling the engine EN are provided. . Further, the oil pan 90 is provided with a temperature sensor 79 that detects the temperature of the oil stored in the oil pan 90.

  The ECU 5 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and controls the operation of the entire engine system A based on the output from each sensor. The ECU 5 corresponds to a control unit.

  Next, the exhaust side variable valve operating apparatus 1E will be described in detail. 2 and 3 are external views of the exhaust side variable valve operating apparatus 1E of the present embodiment. The exhaust side variable valve operating apparatus 1E includes an exhaust side camshaft ES and a cam unit CU provided on the exhaust side camshaft ES. The exhaust side camshaft ES includes a portion SA connected to one end of the cam unit CU and a portion SB connected to the other end of the cam unit CU. The exhaust side camshaft ES is rotated by the power from the internal combustion engine. When the cam unit CU rotates together with the exhaust side camshaft ES, the exhaust valve EV is lifted via the rocker arm R. The exhaust valve EV is an intake valve or an exhaust valve of the internal combustion engine.

  The cam unit CU includes a cam base portion 10 having a diameter larger than that of the cam shaft S and connected to the portions SA and SB of the cam shaft S, and two cam lobe portions 20 connected to the cam base portion 10. The cam base portion 10 has a substantially cylindrical shape, and has a substantially circular base circle portion 11 when viewed from the axial direction of the camshaft S (hereinafter referred to as the axial direction). The base circle portion 11 corresponds to the outer peripheral surface of the cam base portion 10. The two cam lobes 20 are arranged at a predetermined interval in the axial direction. The two cam lobes 20 push the two rocker arms R to lift the two exhaust valves EV. The axial thickness of the cam base portion 10 is thicker than the axial thickness of the cam lobe portion 20.

  As shown in FIG. 3, the cam base portion 10 has a recess 10 </ b> H formed between two cam lobe portions 20. The recess 10 </ b> H is formed between portions where the two rocker arms R contact the cam base portion 10. The recess 10H does not contact the rocker arm R. The support shaft 33 penetrates the cam base 10 and the two cam lobes 20 in the axial direction. The cam lobe portion 20 swings with respect to the cam base portion 10 with the support shaft 33 as a fulcrum. The cam lobe portion 20 can swing between a high position protruding from the base circle portion 11 of the cam base portion 10 to the maximum and a low position protruding from the base circle portion 11 and lower than the high position. A part of the support shaft 33 is exposed in the recess 10H. Each of the two cam lobes 20 is provided with a stopper pin 34P.

  In the recess 10 </ b> H of the cam base 10, two springs 34 </ b> S are wound around the support shaft 33. One end of the spring 34S pushes the inner surface of the recess 10H, and the other end of the spring 34S pushes the stopper pin 34P. That is, the spring 34S biases the stopper pin 34P so that it is separated from the recess 10H. As a result, the cam lobe portion 20 is biased so as to protrude from the cam base portion 10. The spring 34S is an example of an urging member.

  2 and 3, the two cam lobes 20 are both in the low position. In the case of this embodiment, when the cam lobe 20 is locked at the high position, the cam lobe 20 drives the rocker arm R to lift the exhaust valve EV. The cam lobe 20 lifts the exhaust valve EV when it is in either the low position or the high position.

  4A and 4B are sectional views of the cam unit CU as seen from the axial direction. 4A shows the cam lobe 20 in the high position, and FIG. 4B shows the cam lobe 20 in the low position. The cam lobe portion 20 has a substantially U shape or a substantially L shape that avoids the supply path T of the cam base portion 10. A support shaft 33 passes through the base end side of the cam lobe portion 20. 4A and 4B, the camshaft S rotates clockwise. Along with this, the cam base 10 and the cam lobe 20 also rotate clockwise. A long hole 14 through which the stopper pin 34P passes is formed in the cam base portion 10. The long hole 14 regulates the movement range of the stopper pin 34 </ b> P that moves along with the rocking of the cam lobe 20, thereby restricting the rocking range of the cam lobe 20.

  As shown in FIGS. 4A and 4B, the cam lobe 20 protrudes from the cam base 10 even when the cam lobe 20 is in the low position. As will be described in detail later, when the cam lobe portion 20 is at the high position, the operating angle of the exhaust valve EV is large, and when the cam lobe portion 20 is at the low position, the operating angle of the exhaust valve EV is small. Further, the shape of the cam lobe portion 20 is formed so that the exhaust valve EV closing timing is substantially the same regardless of whether the cam lobe portion 20 is in the high position or the low position. However, the shape of the cam lobe portion 20 is such that the opening timing of the exhaust valve EV when the cam lobe portion 20 is at the low position is delayed from the opening timing of the exhaust valve EV when the cam lobe portion 20 is at the high position. Designed.

  5A and 5B are cross-sectional views showing the internal structure of the cam unit CU. 5A and 5B, the two cam lobes 20 are in a lifted state. 5A and 5B correspond to the AA sectional view of FIG. 4A and the BB sectional view of FIG. 4B, respectively. As shown in FIGS. 5A and 5B, the cam unit CU is formed symmetrically in the axial direction at the center of the cam unit CU in the axial direction. Therefore, in the following description, one of the two cam lobes 20 will be described. The cam base portion 10 is formed with a slit 12 that can accommodate the cam lobe portion 20. In the cam base portion 10, a supply path T extending on the axis of the camshaft S and paths T5 and T6 extending radially outward from the supply path T are formed. The paths T5 and T6 each extend radially outward from the supply path T, and then extend in the axial direction to the two cam lobe portions. The route T6 is an example of a first route. The route T5 is an example of a second route.

  The oil control valve OCV2 can linearly adjust the hydraulic pressure supplied into the supply path T by the oil pump P based on the current value applied to the oil control valve OCV2. The oil control valve OCV2 is an example of a hydraulic control valve. The same applies to the oil control valve OCV1. The hydraulic control valve may be capable of adjusting the hydraulic pressure supplied into the supply path T in stages. The ECU 5 includes a CPU, a ROM, a RAM, and the like, and controls the operation of the entire internal combustion engine. The ROM stores a program for executing control described later.

  The cam base portion 10 holds pins 15P, 16P, and 17P that act on the two cam lobe portions 20, respectively. Each of the two cam lobes 20 holds a pin 26P. The pin 26P is an example of a lock member. FIG. 5B is a diagram in which the pins 15P and the like are omitted. The cam lobe portion 20 has a free end portion away from the base end portion through which the support shaft 33 passes, and a hole 26 holding a pin 26P is formed on the free end portion side of the cam lobe portion 20. The hole 26 penetrates the cam lobe 20 in the axial direction. The hole 26 is an example of a holding hole.

  Holes 15 and 16 communicating with the slit 12 are formed in the cam base portion 10. The holes 15 and 16 are formed on the same side with respect to the slit 12. The holes 15 and 16 extend in the axial direction and have a bottom surface. Pins 15P and 16P are accommodated in the holes 15 and 16, respectively. A spring 15S connected to the pin 15P is arranged between the bottom surface of the hole 15 and the pin 15P. A spring 16S connected to the pin 16P is disposed between the bottom surface of the hole 16 and the pin 16P. The spring 16S biases the pin 16P toward the cam lobe portion 20. The spring 15S is set to such a length that the pin 15P does not detach from the hole 15. The spring 15S is an example of a second spring. The spring 16S is an example of a first spring.

  A hole 17 is formed in the cam base portion 10 so as to face the hole 16 through the slit 12. In the hole 17, a pin 17P is accommodated. The hole 17 communicates with the path T6. The hole 17 is located coaxially with the hole 16. The hole 17 extends in the axial direction.

  When the cam lobe 20 is at a high position, the holes 16, 17, and 26 are aligned in the axial direction, and the pins 16P, 17P, and 26P are aligned in the axial direction. In other words, the swing range of the cam lobe portion 20 is defined by the long hole 14 engaged with the stopper pin 34P so that the cam lobe portion 20 is positioned at such a position at one end of the swing range. In the lift state, the pin 16P is inserted into the holes 16 and 26 in common by the biasing force of the spring 16S, and the pin 26P is inserted into the holes 26 and 17 in common. Thereby, the cam lobe part 20 is locked to the cam base part 10 in a lift state. The hole 17 is an example of a first lock hole.

  Next, the locking of the cam lobe 20 will be described in detail. 6A to 7B are explanatory diagrams of the lock of the cam lobe portion 20. When oil is supplied into the paths T5 and T6 via the supply path T by the oil control valve OCV2 and the oil pump P, the pin 17P resists the biasing force of the spring 16S as shown in FIG. Pushed to the side. Thereby, the pin 16P is detached from the hole 26, and the pin 26P is detached from the hole 17. That is, the pins 16P, 17P, and 26P are accommodated in the holes 16, 17, and 26, respectively. As a result, the cam lobe 20 is unlocked at the high position.

  When the camshaft S rotates with the cam lobe 20 unlocked, the cam lobe 20 receives the reaction force from the rocker arm R in order. As a result, as shown in FIG. 6B, the cam lobe 20 moves to a low position against the urging force of the spring 34S. In other words, the biasing force of the spring 34S is set to such an extent that the cam lobe 20 can be moved to a low position only by the reaction force from the rocker arm R in a state where the lock of the cam lobe 20 is released. In this way, the rocker arm R urges the cam lobe portion 20 that has been unlocked to the low position side. When the cam lobe portion 20 is in the low position, the holes 15 and 26 are aligned on the same axis. In other words, the swing range of the cam lobe portion 20 is defined by the long hole 14 engaged with the stopper pin 34P so that the cam lobe portion 20 is positioned at such a position at the other end of the swing range. The rocker arm R is an example of a cam follower for driving a bubble. The cam follower may be a valve lifter that is directly driven by the cam.

  The pin 26P is inserted in common into the holes 15 and 26 against the urging force of the spring 15S as shown in FIG. 6C due to the pressure of oil from the path T5. Thereby, the cam lobe part 20 is locked in a lift stop state. In this way, the cam lobe portion 20 is locked at the low position while the oil is being supplied into the supply path T at a predetermined pressure or higher. The hole 15 is an example of a second lock hole.

  Next, when the oil supply to the supply path T is stopped by the oil control valve OCV2, the pin 26P is detached from the hole 15 and accommodated in the hole 26 by the urging force of the spring 15S as shown in FIG. 7A. As a result, the cam lobe 20 is unlocked at the low position.

  Next, according to the urging force of the spring 34S, the cam lobe portion 20 moves from the low position to the high position as shown in FIG. 7B. Actually, while the cam lobe 20 is not in contact with the rocker arm R, the cam lobe 20 moves to a high position according to the biasing force of the spring 34S. In the state where the cam lobe 20 is at the high position, the pins 16P, 26P, and 17P are arranged in the axial direction as described above.

  In this state, as shown in FIG. 5A, the pin 16P is inserted into the holes 16 and 26 in common according to the urging force of the spring 16S, and similarly the pin 26P is inserted into the holes 26 and 17 in common. Thereby, the cam lobe part 20 is locked in a high position. As described above, the cam lobe 20 is locked at the high position and the low position. The hole 26, the pin 26P, the springs 15S and 16S, the holes 15 and 17 and the like are examples of a lock mechanism. Thus, since the cam lobe part 20 is locked even at a low position, the cam lobe part 20 can be held in a stable state, and reliability and durability are ensured.

  As shown in FIGS. 2, 3, 4 A, 4 B, 5 A, and 5 B, the cam base portion 10 is connected to the cam shaft S, and the cam shaft S does not penetrate the cam base portion 10. For this reason, the axial cross-sectional area of the cam base part 10 can be ensured, and the strength of the cam base part 10 can be ensured. Since the camshaft S does not penetrate the cam base portion 10, it is not necessary to reduce the diameter of the camshaft S. For this reason, the strength of the camshaft S is also ensured. The holes 15, 16, and 17 formed in the cam base portion 10, the holes 26 formed in the cam lobe portion 20, and the like all extend in the axial direction. For this reason, for example, compared with the case where a hole extending in a direction crossing the axial direction is provided and a pin sliding in the hole is arranged, the cross-sectional area in the axial direction of the cam base portion 10 can be secured. . Thereby, the strength of the cam unit CU is ensured.

  As shown in FIGS. 4A and 4B, the free end of the cam lobe portion 20 is separated from the base end side of the cam lobe portion 20 in the reverse direction from the rotational direction of the cam shaft S. Here, the base end side of the cam lobe portion 20 serves as a fulcrum for swinging by the support shaft 33. For this reason, it becomes easy for the cam lobe portion 20 to swing in the direction opposite to the rotation direction of the camshaft S due to the reaction force of the rocker arm R. This facilitates the movement of the cam lobe portion 20 from the low position to the high position in the unlocked state. Moreover, the load by the reaction force from the rocker arm R which the cam lobe part 20 receives when moving to a low position is reduced, and the durability of the cam lobe part 20 is ensured.

  The cam base portion 10 supports two cam lobe portions 20. For this reason, since the cam base part 10 has secured the length of the axial direction, the intensity | strength is ensured. In addition, since the cam base portion 10 is shared by the two cam lobe portions 20, the number of parts is reduced. Further, since the support shaft 33 penetrates the two cam lobes 20 in common, the number of parts is also reduced.

  As shown in FIGS. 2 and 3, the springs 15 </ b> S, 16 </ b> S, and 34 </ b> S are disposed in the axial direction with respect to the cam lobe portion 20. For example, compared with the case where such a spring 34S etc. is arrange | positioned in the position which overlaps with the cam lobe part 20 in a radial direction, the cross-sectional area in the axial direction of the cam lobe part 20 is securable. Thereby, the strength of the cam lobe portion 20 can be ensured.

  Further, as described above, the recess 10H in which the spring S34 is disposed is provided in a portion that does not contact the rocker arm R, and this portion is effectively used. Since the spring S34 is disposed at a position retracted from the portion of the cam base portion 10 that contacts the rocker arm R, the cross-sectional area in the axial direction of the portion of the cam base portion 10 that contacts the rocker arm R is also secured. Thereby, the strength of the cam base portion 10 is also ensured.

  As shown in FIG. 4A, the outlet of the path T5 is formed so as to open to the slit 12, and this outlet is formed at a position away from the cam lobe portion 20 in the lifted state. For this reason, in the lift state, by supplying oil to the supply path T, the oil can be supplied from the outlet of the path T5 to the rocker arm R and the like via the slit 12. Thereby, lubrication of the rocker arm R and the cam unit CU can be ensured. Moreover, even if the conventional cam shower mechanism is abolished, lubrication can be promoted by the exhaust side variable valve operating apparatus 1E of the present embodiment.

  As described above, the exhaust side variable valve operating apparatus 1E changes the working angle of the exhaust valve EV in multiple stages by hydraulic pressure.

  Next, the intake side variable valve operating apparatus 1I will be described. FIG. 8 is an explanatory diagram of the intake side variable valve operating apparatus 1I. The intake-side variable valve apparatus 1I is an electric variable valve apparatus that continuously changes the maximum lift amount and operating angle of the intake valve IV by the power of the motor 160. Since the detailed structure of the intake side variable valve operating apparatus 1I is described in, for example, Japanese Patent Application Laid-Open No. 2010-180865 and the like, only the outline will be described below. The intake-side variable valve operating apparatus 1I includes a control shaft 140, a motor 160 that drives the control shaft 140 in the axial direction, and a conversion mechanism that reciprocates the control shaft 140 by converting the rotation of the motor 160 into a linear motion. The control shaft 140 and the output shaft 160A of the motor 160 are connected via a fastening member 180.

  The control shaft 140 is provided with a roller arm 200 and a pair of swing cams 220 located on both sides of the roller arm 200. The above-described cam of the intake camshaft IS is in contact with the roller of the roller arm 200. When the intake camshaft IS rotates, the roller arm 200 is swung. The swing cam 220 swings together with the roller arm 200. The swing cam 220 is in contact with the roller of the rocker arm R. When the swing cam 220 swings, the rocker arm R swings and the rocker arm R presses the intake valve IV, thereby driving the intake valve IV.

  Helical splines having spiral shapes in opposite directions are formed on the inner peripheral portions of the roller arm 200 and the swing cam 220. A slider gear that meshes with the helical spline is disposed inside the roller arm 200 and the swing cam 220. The slider gear moves in the axial direction together with the control shaft 140. When the control shaft 140 is moved in the axial direction, the relative phase between the roller arm 200 and the swing cam 220 changes due to the action of the helical spline and the slider gear. As a result, the maximum lift amount and operating angle of the intake valve IV change continuously by changing the swing range of the swing cam 220 as the intake camshaft IS rotates. Such a roller arm 200 and a swing cam 220 are provided for each cylinder.

  In the intake side variable valve operating apparatus 1I, both the operating angle and the maximum lift amount of the intake valve IV are continuously reduced by moving the control shaft 140 in one direction (for example, the right direction in FIG. 1) by the motor 160. . On the other hand, both the operating angle and the maximum lift amount of the intake valve IV can be continuously increased by moving the control shaft 140 in the opposite direction (for example, the left direction in FIG. 1).

  A rotation amount sensor 260 that detects the rotation amount of the motor 160 is provided. The motor 160 and the rotation amount sensor 260 are connected to the ECU 5. The ECU 5 can grasp the rotation amount of the motor 160 from the output value of the rotation amount sensor 260. Thereby, the ECU 5 can grasp the position of the control shaft 140 and grasp the operating angle and the maximum lift amount of the intake valve IV.

  The control shaft 140 is rotatably supported by a bearing portion 150 provided in a cylinder head or the like of the engine EN. A plurality of bearing portions 150 are provided so as to sandwich the roller arm 200 and the swing cam 220. An opening 152 for supplying oil to the outer peripheral surface 141 of the control shaft 140 is formed in the bearing portion 150. The opening 152 is formed on the inner peripheral surface of the bearing portion 150 and faces the control shaft 140. The opening 152 communicates with an oil passage formed in the bearing portion 150. Oil is supplied to the oil passage by the oil control valve OCV1 and is discharged from the opening 152. Further, a groove 142 is formed in the outer peripheral surface 141 of the control shaft 140 facing the opening 152.

  9A to 9C are explanatory views of the groove 142. FIG. 9A is a perspective view of the control shaft 140 showing the groove 142 with the control shaft 140 removed from the bearing portion 150. The groove 142 includes an inclined surface 143 that is inclined downward from the outer peripheral surface 141 and a bottom surface 144 that is continuous with the inclined surface 143. The bottom surface 144 is curved around the axial direction of the control shaft 140. The inclined surface 143 is formed on the side on which the control shaft 140 moves when the operating angle of the intake valve IV is expanded, and the bottom surface 144 is formed on the side on which the control shaft 140 moves when reducing the operating angle of the intake valve IV. Has been.

  9B and 9C are explanatory views of the positional relationship between the opening 152 and the groove 142. As shown in FIG. 9B, when the operating angle and the maximum lift amount of the intake valve IV are set to the maximum, the inclined surface 143 of the groove 142 and the opening 152 are opposed to each other. Thereby, the oil discharged from the opening 152 flows from the inclined surface 143 toward the bottom surface 144 and flows from the bottom surface 144 to the outer peripheral surface 141. The oil flows from the outer peripheral surface 141 toward the roller arm 200 and the swing cam 220 adjacent to the bearing portion 150, and lubrication between the roller arm 200, the swing cam 220 and the control shaft 140 is ensured.

  As shown in FIG. 9C, when the operating angle and the maximum lift amount of the intake valve IV are set to the minimum, the opening 152 partially faces the outer peripheral surface 141 and the groove 142. Specifically, the boundary portion between the outer peripheral surface 141 and the inclined surface 143 is located at the center of the opening 152. Thereby, the aperture ratio of the opening 152 is halved as compared with the fully opened state. As the aperture ratio of the opening 152 is reduced, the flow rate of oil discharged from the opening 152 is also reduced. Thus, when the control shaft 140 is driven so that the operating angle of the intake valve IV is increased, the aperture ratio of the opening 152 increases, and when the control shaft 140 is driven so that the operating angle of the intake valve IV is reduced, the opening 152 The aperture ratio is also reduced. The groove part 142 is an example of a changing part. The minimum aperture ratio of the opening 152 is not limited to 50%, and the maximum aperture ratio is not limited to 100%.

  Next, control executed by the ECU 5 will be described. FIG. 10 is a flowchart illustrating an example of control executed by the ECU 5. FIG. 10 is a flowchart in a case where the operating angle of the exhaust valve EV is shifted from the expanded state to the contracted state. The ECU 5 determines whether or not there is a request for supplying oil to the exhaust side variable valve operating apparatus 1E that is required according to the operating state of the engine EN (step S1). That is, it is determined whether or not there is a request to reduce the working angle of the exhaust valve EV. In the case of negative determination, the ECU 5 ends this control.

  In the case of an affirmative determination, the ECU 5 determines whether or not the hydraulic pressure is equal to or less than the first threshold value (step S2). Specifically, the ECU 5 estimates the hydraulic pressure based on the map shown in FIG. FIG. 11 is a map showing the oil pressure according to the oil temperature and the engine speed, and is recorded in the ROM of the ECU 5 in advance. The oil pressure is the oil pressure immediately before passing through the oil control valve OCV1. The temperature of the oil can be acquired from the output value from the temperature sensor 79. The rotational speed of the engine EN can be obtained from the output value from the crank angle sensor 71. Generally, the higher the oil temperature, the lower the oil pressure. Further, since the oil pump that supplies oil is driven by the rotation of the crankshaft 48, the hydraulic pressure tends to decrease as the engine speed decreases. The ECU 5 determines whether or not the hydraulic pressure estimated based on the output values of the temperature sensor 79 and the crank angle sensor 71 is equal to or less than the first threshold value.

  In the negative determination, that is, when the ECU 5 determines that the hydraulic pressure is higher than the first threshold, the ECU 5 supplies oil to the exhaust side variable valve operating apparatus 1E as requested to switch the state of the cam lobe portion 20. (Step S3). If the determination is affirmative, that is, if the ECU 5 determines that the hydraulic pressure is equal to or lower than the first threshold, the control shaft 140 is moved so that the aperture ratio of the aperture 152 is reduced as shown in FIG. 9C (step S4). In other words, the control shaft 140 is moved so that the operating angle and the maximum lift amount of the intake valve IV are reduced. Thereby, since the flow rate of the oil discharged from the opening 152 is decreased, the amount of oil supplied to the bearing portion 150 can be reduced. In this state, the ECU 5 supplies oil to the exhaust side variable valve operating apparatus 1E (step S5). As a result, the cam lobe 20 moves from the high position to the low position, and the operating angle and the maximum lift amount of the exhaust valve EV are reduced.

  In this way, when the hydraulic pressure is low, the amount of oil consumed for lubrication on the control shaft 140 side is reduced, and the oil is supplied to the exhaust side variable valve operating apparatus 1E to switch the position of the cam lobe portion 20. Thereby, it can suppress that the oil_pressure | hydraulic supplied to the exhaust side variable valve apparatus 1E side falls, and can suppress that the responsiveness of the switching of the exhaust side variable valve apparatus 1E deteriorates.

  Note that after the cam lobe 20 has moved to the low position, the ECU 5 moves the control shaft 140 in accordance with the operating state of the engine EN. When the processes of steps S4 and S5 are executed, for example, when the engine EN shifts from a low rotation and low load state to a low rotation and high load state, or when the engine EN speed is low, such as when the engine EN is started. Etc. In addition, you may perform the process of said step S4, S5 simultaneously.

  When it is required to reduce the operating angle of both the intake valve IV and the exhaust valve EV from a state where both operating angles are large, for example, when the valve overlap period is required to be reduced, the above processing is performed. After execution, the operating angle of the intake valve IV is kept small. In this case, there is no need to return the operating angle of the intake valve IV to the original, and the exhaust side variable valve operating apparatus 1E is controlled while controlling the operating angles of the intake valve IV and the exhaust valve EV in accordance with the operation request to the engine EN. Oil supply can be secured.

  FIG. 12 is a flowchart illustrating an example of control executed by the ECU 5. FIG. 12 is a flowchart when the operating angle of the exhaust valve EV shifts from a reduced state to an enlarged state. The ECU 5 determines whether or not there is a request for stopping the supply of oil to the exhaust-side variable valve operating apparatus 1E, which is required according to the operating state of the engine EN (step S11). That is, it is determined whether or not there is a request to increase the operating angle of the exhaust valve EV. In the case of negative determination, the ECU 5 ends this control. If the determination is affirmative, the ECU 5 determines whether or not the hydraulic pressure exceeds the second threshold (step S12). The hydraulic pressure is estimated by the method described above. The second threshold value is larger than the first threshold value, but is not limited to this.

  In the negative determination, that is, when the ECU 5 determines that the hydraulic pressure is equal to or less than the second threshold, the ECU 5 stops the supply of oil to the exhaust side variable valve operating apparatus 1E as requested and changes the state of the cam lobe 20. Switching (step S13). If the determination is affirmative, that is, if the ECU 5 determines that the hydraulic pressure exceeds the second threshold, the control shaft 140 is moved so that the opening ratio of the opening 152 is increased as shown in FIG. S14). That is, the control shaft 140 is moved so as to increase the operating angle of the intake valve IV. Thereby, since the flow rate of the oil discharged from the opening 152 increases, the amount of oil supplied to the bearing portion 150 can be increased. In this state, the ECU 5 supplies oil to the exhaust side variable valve operating apparatus 1E (step S15). As a result, the cam lobe 20 moves from the low position to the high position, and the operating angle and the maximum lift amount of the exhaust valve EV are increased.

  As described above, when the hydraulic pressure is high, the amount of oil consumed for lubrication on the control shaft 140 side is increased, the supply of oil to the exhaust side variable valve operating apparatus 1E is stopped, and the position of the cam lobe portion 20 is switched. Thereby, the hydraulic pressure supplied to the exhaust side variable valve apparatus 1E side can be reduced at an early stage, and deterioration of the switching response of the exhaust side variable valve apparatus 1E can be suppressed.

  Note that after the cam lobe 20 has moved to the high position, the ECU 5 moves the control shaft 140 in accordance with the operating state of the engine EN. Further, when the processes of steps S14 and S15 are executed, for example, the engine EN shifts from a medium rotation high load to a high rotation (regardless of load) state. You may perform the process of said step S14, S15 simultaneously.

  In addition, when it is required to increase the operating angle of both the intake valve IV and the exhaust valve EV from a state where the operating angle of both the intake valve IV and the exhaust valve EV is small, for example, when an increase in the valve overlap period is required, the above processing is performed. After the execution, the operating angle of the intake valve IV is maintained in a large state. In this case, there is no need to return the operating angle of the intake valve IV to the original, and the exhaust valve is supplied to the exhaust-side variable valve gear 1E while controlling the operating angles of the intake valve IV and the exhaust valve EV according to the operation request to the engine EN. The oil pressure that is being used can be reduced early.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

  In the present embodiment, the multistage exhaust side variable valve operating device has been described as an example of the hydraulic variable valve operating device, but the hydraulic variable valve operating device is not limited to this, and the maximum lift amount of the exhaust valve, Other known ones may be adopted as long as at least one of the operating angle and phase can be changed by the action of hydraulic pressure.

  The variable valve operating apparatus that changes the operating characteristic of the intake valve may be other than the above-described embodiment as long as the operating characteristic of the intake valve can be changed by moving the control shaft in the axial direction.

  In this embodiment, the hydraulic variable valve device is provided on the exhaust side and the electric variable valve device is provided on the intake side. However, the present invention is not limited to this. That is, the electric variable valve device may change the operation characteristic of the exhaust valve EV, and the hydraulic variable valve device may change the operation characteristic of the intake valve IV.

  In steps S2 and S12 of the above embodiment, the oil pressure is estimated based on the oil temperature and the engine speed, but the present invention is not limited to this. For example, the oil pressure may be estimated based on only one of the oil temperature and the engine speed. A sensor that directly detects the hydraulic pressure may be provided.

  In the exhaust side variable valve operating apparatus 1E, when the hydraulic pressure is supplied, the working angle and the maximum lift amount of the exhaust valve EV are reduced, and when the hydraulic pressure is stopped, the working angle and the maximum lift amount of the exhaust valve EV are increased. However, it is not limited to this. The hydraulic variable valve device may be configured to expand the working angle of the exhaust valve by supplying hydraulic pressure and reduce the working angle of the exhaust valve by stopping the supply of hydraulic pressure.

  In this embodiment, the case where the cam lobe portion 20 is located at a position protruding from the cam base portion 10 is described as a low position. However, the present invention is not limited to this. For example, the cam lobe portion 20 may swing between a high position protruding from the base circle portion 11 of the cam base portion 10 and a low position not protruding.

  In the lift state, the oil pressure may be applied directly to the pin 26P without using the pin 17P. Further, the springs 15S and 16S may directly bias the pin 26P without using the pins 15P and 16P.

  The cam base portion 10 may be molded integrally with the camshaft ES, or may be joined after being molded separately as in this embodiment.

1I Intake side variable valve gear (variable valve gear)
1E Exhaust-side variable valve gear (hydraulic variable valve gear)
IV Intake valve EV Exhaust valve (cam follower)
5 ECU
R Rocker arm OCV1, OCV2 Oil control valve 10 Cam base part 11 Base circle part 20 Cam lobe part 26 Pin (lock member)
34S Spring (Biasing member)
140 Control shaft 141 Outer peripheral surface 142 Groove portion 143 Inclined surface 144 Bottom surface 150 Bearing portion 152 Opening 160 Motor

Claims (8)

A hydraulic variable valve operating device that changes the operating characteristic of one of the intake valve and the exhaust valve of the internal combustion engine by oil pressure;
A motor, a control shaft that moves in the axial direction by the motor to change the operating characteristics of the other valve of the intake valve and the exhaust valve, and a bearing portion that is formed with an opening for discharging oil to the control shaft and supports the control shaft A variable valve operating apparatus including a changing unit that changes an opening ratio of the opening in accordance with an axial movement of the control shaft;
When changing the operating characteristic of one of the intake valve and the exhaust valve by supplying oil to the hydraulic variable valve device, the control shaft is moved by the changing unit so as to reduce the opening ratio. And a control unit for the internal combustion engine. A hydraulic variable valve operating device that changes the operating characteristic of one of the intake valve and the exhaust valve of the internal combustion engine by oil pressure;
A motor, a control shaft that moves in the axial direction by the motor to change the operating characteristics of the other valve of the intake valve and the exhaust valve, and a bearing portion that is formed with an opening for discharging oil to the control shaft and supports the control shaft A variable valve operating apparatus including a changing unit that changes an opening ratio of the opening in accordance with an axial movement of the control shaft;
When changing the operating characteristic of one of the intake valve and the exhaust valve by stopping the supply of oil to the hydraulic variable valve operating device, the control shaft is configured to increase the opening ratio by the changing unit. And a control unit for moving the internal combustion engine.   The control unit increases the opening ratio by the changing unit when changing the operating characteristic of one of the intake valve and the exhaust valve by stopping the supply of oil to the hydraulic variable valve operating device. The control apparatus for an internal combustion engine according to claim 1, wherein the control shaft is moved as follows. The change part is a groove provided on the outer peripheral surface of the control shaft,
The control device for an internal combustion engine according to claim 1, wherein the opening discharges oil into the groove portion. By supplying oil to the hydraulic variable valve device, at least one of the lift amount and the working angle of one of the intake valve and the exhaust valve is reduced,
By moving the control shaft so as to reduce the opening ratio by the changing unit, at least one of the lift amount and the operating angle of the other valve of the intake valve and the exhaust valve is reduced,
The supply of oil to the hydraulic variable valve device is stopped, and at least one of the lift amount and the working angle of one of the intake valve and the exhaust valve is expanded,
Any one of the lift amount and the working angle of the other valve of the intake valve and the exhaust valve is expanded by moving the control shaft so as to increase the opening ratio by the changing unit. A control device for an internal combustion engine.   The control unit changes an operating characteristic of one of the intake valve and the exhaust valve without changing the opening ratio according to whether the hydraulic pressure is equal to or less than a threshold value or exceeds the threshold value, or the opening ratio The control device for an internal combustion engine according to claim 1, wherein the operating characteristic of one of the intake valve and the exhaust valve is changed by changing the valve.   The control device for an internal combustion engine according to claim 6, wherein the control unit determines whether the hydraulic pressure is higher or lower than the threshold value based on at least one of a temperature of oil and a rotation speed of the internal combustion engine. The hydraulic variable valve operating device is:
A cam base that rotates with the camshaft;
A cam lobe connected to the cam base so as to be swingable between a high position protruding from the outer periphery of the cam base and a low position lower than the high position;
A biasing member that biases the cam lobe portion toward the high position;
A cam follower for urging the cam lobe portion toward the low position;
A lock member that is held by the cam lobe portion and locks the cam lobe portion to the cam base portion at the high position and the low position;
Hydraulic pressure is applied to the lock member so as to switch the lock of the cam lobe portion at the high position, and hydraulic pressure is applied to the lock member to switch the lock of the cam lobe portion at the low position. A control device for an internal combustion engine according to any one of claims 1 to 7, comprising a path to be operated.

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