JP5811052B2 - Variable valve gear - Google Patents

Description

  The present invention relates to a variable valve operating device, and more particularly to a variable valve operating device used for an internal combustion engine.

  2. Description of the Related Art Conventionally, there is known a cam-switching type variable valve device that switches a cam corresponding to a valve of an internal combustion engine by displacing an outer cam having a plurality of cams with respect to the inner shaft in the axial direction of the inner shaft. For example, in Patent Document 1, an outer cam (cam carrier) having a plurality of cams and a groove forming portion in which grooves are formed is arranged on an inner shaft (cam shaft), and a drive pin is engaged with a groove of the outer cam. Thus, there has been disclosed a variable valve gear that displaces the outer cam relative to the inner shaft in the axial direction of the inner shaft.

JP-T-2006-520869

  Since the variable valve apparatus according to Patent Document 1 does not include a configuration for detecting the position of the outer cam in the axial direction with respect to the inner shaft, it is difficult to detect the position of the outer cam in the axial direction with respect to the inner shaft.

  An object of this invention is to provide the variable valve apparatus which can detect the position of the axial direction with respect to the inner shaft of an outer cam.

A variable valve operating apparatus according to the present invention includes an outer cam having a plurality of cams having different cam profiles as cams corresponding to a valve of an internal combustion engine, an inner shaft inserted into the outer cam, and the outer cam. A displacement mechanism for displacing the inner shaft in the axial direction of the inner shaft; and a control device for controlling the displacement mechanism, wherein the inner shaft is formed with a shaft passage that is a passage through which oil passes. The outer cam is formed with an oil communication passage that communicates the shaft passage with the outer peripheral surface of the outer cam, and the oil communication passage has a passage area of the oil communication passage with respect to the inner shaft of the outer cam. The controller is configured to change according to the position in the axial direction, and the control device Based on the pressure of the oil in the shift path to detect the position of the axial direction relative to the inner shaft of the outer cam, the outer peripheral surface of said outer cam is pivotally supported by the cam journal, a plurality of said cams The cam profile of the first cam includes a cam profile in which the valve is not lifted by the first cam, or a lift amount of the valve driven by the first cam is The cam profile is smaller than the lift amount of the valve driven by the second cam, and the oil communication path is positioned in the axial direction of the outer cam relative to the inner shaft. The first cam corresponds to the valve. The shaft passage and the outer peripheral surface of the outer cam. And when the position of the outer cam in the axial direction relative to the inner shaft is a position corresponding to the valve, the shaft passage and the outer peripheral surface of the outer cam And a second oil communication passage, and a passage area of the first oil communication passage is smaller than a passage area of the second oil communication passage .

According to the variable valve operating apparatus of the present invention, when the axial position of the outer cam with respect to the inner shaft changes, the passage area of the oil communication passage changes, and as a result, the oil pressure in the shaft passage also changes. Therefore, the control device can detect the axial position of the outer cam relative to the inner shaft based on the oil pressure in the shaft passage. Thus, according to the variable valve gear according to the present invention, the position of the outer cam in the axial direction relative to the inner shaft can be detected.
Further, according to the variable valve operating apparatus according to the present invention, the first oil communication passage having a relatively small passage area is formed between the shaft passage and the outer peripheral surface of the outer cam according to the axial position of the outer cam with respect to the inner shaft. And a state in which the second oil communication passage having a relatively large passage area communicates between the shaft passage and the outer peripheral surface of the outer cam. As a result, the passage area of the oil communication passage that communicates the shaft passage and the outer peripheral surface of the outer cam can be changed according to the position of the outer cam in the axial direction with respect to the inner shaft.

Furthermore, according to the variable valve operating apparatus according to the present invention, since the outer peripheral surface of the outer cam is pivotally supported by the cam journal, the outer cam is supplied to the outer peripheral surface of the outer cam through the oil communication passage of the outer cam. Oil can be used to lubricate the outer cam and cam journal. According to this configuration, the cam profile of the first cam is a cam profile in which the valve is not lifted by the first cam, or the lift amount of the valve driven by the first cam is the lift of the valve driven by the second cam. Since the cam profile is smaller than the amount, the magnitude of the urging force that the outer cam receives from the valve when the first cam corresponds to the valve is such that the outer cam moves from the valve when the second cam corresponds to the valve. It is smaller than the magnitude of the biasing force it receives. Therefore, as a result of the passage area of the first oil communication passage being smaller than the passage area of the second oil communication passage, the amount of oil that passes through the first oil communication passage and is supplied to the outer peripheral surface of the outer cam is the second oil communication passage. Even if the amount of oil is less than the amount of oil that passes through the outer cam and is supplied to the outer peripheral surface of the outer cam, wear of the outer cam and the cam journal can be suppressed.

  In the above configuration, the control device may further determine whether or not the position of the outer cam in the axial direction with respect to the inner shaft is abnormal based on the pressure of the oil in the shaft passage. According to this configuration, it is possible to detect an abnormality in the position of the outer cam in the axial direction with respect to the inner shaft.

  In the above configuration, the control device may be configured so that the outer cam is displaced in the axial direction with respect to the inner shaft when the position of the outer cam in the axial direction with respect to the inner shaft is abnormal. After controlling the displacement mechanism, the axial position of the outer cam relative to the inner shaft is detected based on the oil pressure in the shaft passage, and the displacement is detected based on the position detection result. It may be further determined whether or not there is an abnormality in the mechanism.

  If the position of the outer cam in the axial direction relative to the inner shaft is abnormal, the position of the outer cam in the axial direction relative to the inner shaft does not become normal even if the displacement mechanism is controlled. It is done. Therefore, according to this configuration, an abnormality of the displacement mechanism can be detected.

  In the above configuration, when there is no abnormality in the displacement mechanism, the control device controls the displacement mechanism so that the outer cam is displaced in the axial direction with respect to the inner shaft. The cam switching control for switching the cam corresponding to the valve between the plurality of cams of the outer cam is executed, and after the cam switching control is executed, the internal combustion engine after the cam switching control is executed. When the operation state change control is executed to change at least one of the fuel injection amount and the ignition timing of the internal combustion engine according to the type of the cam corresponding to the valve, and the control device has an abnormality in the displacement mechanism The cam switching control may be prohibited from being executed.

  According to this configuration, when the cam switching control is executed and the operating state change control is executed when there is no abnormality in the displacement mechanism, at least one of the fuel injection amount and the ignition timing of the internal combustion engine is set after the cam switching control. It can be changed according to the type of cam corresponding to the valve. Thereby, the operating state of the internal combustion engine can be appropriately controlled according to the type of cam corresponding to the valve. Further, according to this configuration, it is possible to prevent the cam switching control from being executed and the operation state change control from being executed even though there is an abnormality in the displacement mechanism. As a result, it is possible to suppress the occurrence of problems associated with the cam switching control being executed and the operating state change control being executed despite the abnormality in the displacement mechanism.

  ADVANTAGE OF THE INVENTION According to this invention, the variable valve apparatus which can detect the position of the axial direction with respect to the inner shaft of an outer cam can be provided.

FIG. 1A is a schematic diagram for explaining the variable valve gear according to the first embodiment. FIG. 1B is a schematic cross-sectional view for explaining the configuration around the valve of the internal combustion engine. FIG. 2A is a schematic cross-sectional view enlarging the vicinity of the # 1 cylinder of the variable valve system. FIG. 2B is a schematic cross-sectional view enlarging the vicinity of the connecting portion of the outer cam. FIG. 2C is a schematic cross-sectional view for explaining the locking mechanism. FIG. 3A and FIG. 3B are schematic cross-sectional views showing how the outer cam is displaced in the axial direction. FIG. 4A is a schematic diagram for explaining the details of the groove. FIG. 4B to FIG. 4D are schematic views for explaining an engagement mode of the groove engaging member with the groove. FIG. 5 is a diagram for explaining a map of the reference pressure of the shaft passage used in the cam position detection abnormality determination control according to the first embodiment. FIG. 6 is a diagram illustrating an example of a flowchart when the control device according to the first embodiment executes cam position detection abnormality determination control. FIG. 7 is a diagram illustrating an example of a flowchart when the control device according to the first embodiment executes the operation state change control. FIG. 8 is a diagram for explaining a map of the reference pressure of the shaft passage used in the cam position detection abnormality determination control according to the second embodiment. FIG. 9 is a diagram illustrating an example of a flowchart when the control device according to the second embodiment executes cam position detection abnormality determination control. FIG. 10 is a diagram illustrating an example of a flowchart when the control device according to the third embodiment executes displacement mechanism abnormality determination control. FIG. 11 is a diagram illustrating an example of a flowchart when the control device according to the third embodiment executes the control when the displacement mechanism is abnormal.

  Hereinafter, modes for carrying out the present invention will be described.

  A variable valve apparatus 5 according to Embodiment 1 of the present invention will be described. FIG. 1A is a schematic diagram for explaining the variable valve gear 5. The variable valve gear 5 is arranged in the internal combustion engine. First, the configuration of the internal combustion engine in which the variable valve operating device 5 is arranged will be described, and then the configuration of the variable valve operating device 5 will be described. The internal combustion engine in which the variable valve gear 5 is arranged includes a plurality of cylinders 100. The internal combustion engine according to the present embodiment has four cylinders as the plurality of cylinders 100.

  In FIG. 1A, the left side is the right front wheel (Fr) side of the vehicle on which the internal combustion engine is mounted, and the right side is the right rear wheel (Rr) side. In FIG. 1A, the cylinder arrangement direction of the plurality of cylinders 100 is the horizontal direction (left-right direction), which is also the direction from the Fr side to the Rr side. The plurality of cylinders 100 are referred to as the # 1 cylinder 100, the # 2 cylinder 100, the # 3 cylinder 100, and the # 4 cylinder 100 in order from the left side. However, the arrangement mode of the internal combustion engine in the vehicle is not limited to such an arrangement mode. For example, the internal combustion engine is arranged in the vehicle so that the cylinder arrangement direction is a direction from the left front wheel side to the left rear wheel side. It may be arranged.

  The internal combustion engine according to the present embodiment includes a valve 110 in each cylinder 100. In FIG. 1A, only the valve 110 of the # 1 cylinder 100 is shown, and the valves 110 of the other cylinders 100 are not shown. The valve 110 is an intake valve that opens and closes an intake port formed in the cylinder 100 or an exhaust valve that opens and closes an exhaust port. The internal combustion engine according to the present embodiment has two intake ports and two exhaust ports per cylinder 100. Therefore, the internal combustion engine has two intake valves and two exhaust valves per 100 cylinders. In the present embodiment, an intake valve is used as the valve 110. The valve 110 is driven by a cam to open and close the intake port.

  FIG. 1B is a schematic cross-sectional view for explaining the configuration around the valve 110 of the internal combustion engine. The internal combustion engine includes a rocker arm 111 and a valve spring 112 around the valve 110. The rocker arm 111 has a function as a cam power transmission member that transmits cam power to the valve 110. As described above, the driving method of the valve 110 by the cam according to the present embodiment is a rocker arm driving method, but the driving method of the valve 110 by the cam is not limited to this. As another example of the drive system of the valve 110 by the cam, for example, a direct drive system can be used.

  The valve spring 112 urges the valve 110 toward the rocker arm 111. That is, the valve spring 112 biases the valve 110 in the closing direction. The cam lifts the valve 110 via the rocker arm 111 so as to oppose the urging force of the valve spring 112. When the valve 110 is lifted, the intake port is opened.

  Next, the configuration of the variable valve gear 5 will be described. With reference to FIG. 1A, the variable valve gear 5 includes an inner shaft 10, an outer cam 20, a displacement mechanism 30, various sensors, and a control device 50. A rotation center axis (hereinafter referred to as axis 11) of the inner shaft 10 extends in a direction along the cylinder arrangement direction. In FIG. 1A, the direction of the axis 11 of the inner shaft 10 (hereinafter, the direction of the axis 11 of the inner shaft 10 may be abbreviated as the axis direction) is the horizontal direction. This axial direction is the same as the axial direction of the crankshaft of the internal combustion engine.

  The inner shaft 10 is inserted into the outer cam 20. The power of the crankshaft of the internal combustion engine is transmitted to the inner shaft 10 via a power transmission member (a belt or a chain, a sprocket engaged with these). Thereby, the inner shaft 10 rotates around the axis line 11 in synchronization with the crankshaft.

  The outer cam 20 has a plurality of cams having different cam profiles as cams corresponding to the valve 110 of the internal combustion engine. Details of the configuration of the outer cam 20 will be described later with reference to FIG. The outer cam 20 is disposed so as to correspond to each cylinder 100. Specifically, the variable valve apparatus 5 according to the present embodiment includes a total of four outer valves so as to correspond to the # 1 cylinder 100, the # 2 cylinder 100, the # 3 cylinder 100, and the # 4 cylinder 100, respectively. A cam 20 is provided.

  The outer cam 20 is externally fitted to the inner shaft 10 so that it can be displaced relative to the inner shaft 10 in the axial direction of the inner shaft 10. The outer cam 20 is externally fitted to the inner shaft 10 so as to rotate integrally with the inner shaft 10 when the inner shaft 10 rotates.

  Specifically, a spline (not shown) is formed in a portion where at least each outer cam 20 of the inner shaft 10 according to this embodiment slides, and the inner peripheral surface of each outer cam 20 is also formed. Splines (not shown) corresponding to the splines of the inner shaft 10 are formed. With this configuration, when the inner shaft 10 rotates, the outer cam 20 can rotate integrally with the inner shaft 10, and the outer cam 20 is displaced relative to the inner shaft 10 in the axial direction of the inner shaft 10. be able to. The mechanism for rotating the outer cam 20 integrally with the inner shaft 10 while allowing the outer cam 20 to move in the axial direction relative to the inner shaft 10 is not limited to a mechanism using a spline as in this embodiment. Absent.

  The inner shaft 10 and the outer cam 20 are pivotally supported by a cam journal 120 included in the internal combustion engine. The cam journal 120 according to the present embodiment is formed on a cylinder head of an internal combustion engine body (portion including a cylinder block and a cylinder head) of the internal combustion engine.

  The cam journal 120 according to the present embodiment pivotally supports the inner shaft 10 and the outer cam 20 at six locations described below. Specifically, the cam journal 120 includes a left portion (hereinafter, sometimes referred to as a left end portion) of the # 1 cylinder 100 and a right portion (hereinafter, referred to as a left end portion) of the # 4 cylinder 100 shown in FIG. The inner shaft 10 is pivotally supported.

  The cam journal 120 pivotally supports the outer cam 20 in a portion between the pair of valves 110 of each cylinder 100 in the region between the left end portion and the right end portion. Specifically, the cam journal 120 includes a portion between the pair of valves 110 of the # 1 cylinder 100, a portion between the pair of valves 110 of the # 2 cylinder 100, and a pair of valves 110 of the # 3 cylinder 100. The outer cam 20 is pivotally supported in the intermediate portion and in the portion between the pair of valves 110 of the # 4 cylinder 100. However, the shaft support location of the inner shaft 10 and the outer cam 20 by the cam journal 120 is not limited to the location shown in FIG.

  The inner shaft 10 is provided with a shaft passage 12 that is a passage through which oil passes. The shaft passage 12 according to the present embodiment is formed from one end side of the inner shaft 10 to the other end side along the axial direction of the inner shaft 10. Specifically, the shaft passage 12 according to the present embodiment is from a portion pivotally supported by the cam journal 120 at the left end portion of the inner shaft 10 from a portion pivotally supported by the cam journal 120 at the right end portion of the inner shaft 10. Is also formed along the axial direction on the right side.

  The cam journal 120 at the left end of the cam journal 120 according to the present embodiment is provided with a journal passage 125 that is a passage through which oil passes. The shaft passage 12 and the journal passage 125 are configured so that the oil that has passed through the journal passage 125 is supplied to the left end portion of the shaft passage 12. The oil pumped by the oil pump is supplied to the journal passage 125 and then flows into the left end portion of the shaft passage 12. The oil flowing into the shaft passage 12 passes through the oil communication passage described later of the outer cam 20 while passing through the shaft passage 12 and is supplied to the outer peripheral surface of the outer cam 20. Used for lubrication.

  The oil that has been used for lubrication of the outer cam 20 and the cam journal 120 is then recovered by an oil pan of the internal combustion engine and pumped again by an oil pump. In this way, the oil circulates between the internal combustion engine and the variable valve gear 5. The configuration for supplying oil to the shaft passage 12 is limited to the configuration for supplying oil to the shaft passage 12 from the journal passage 125 provided in the cam journal 120 at the left end of the # 1 cylinder 100 as in this embodiment. Is not to be done.

  The displacement mechanism 30 is a mechanism that displaces the outer cam 20 in the axial direction with respect to the inner shaft 10. The operation of the displacement mechanism 30 is controlled by the control device 50. A total of four displacement mechanisms 30 according to the present embodiment are arranged so as to correspond to the respective outer cams 20. Details of the displacement mechanism 30 will be described later with reference to FIG.

  The various sensors are sensors for detecting information necessary for the operation of the control device 50. FIG. 1A shows a crank position sensor 40, a cam position sensor 41, and a pressure sensor 42 as examples of various sensors. The crank position sensor 40 detects the crank angle and transmits the detection result to the control device 50. The cam position sensor 41 detects the rotation angle of the inner shaft 10 and transmits the detection result to the control device 50. The control device 50 acquires an angle with respect to the crank angle of the inner shaft 10 based on the detection result of the cam position sensor 41 and the detection result of the crank position sensor 40.

  The pressure sensor 42 detects the oil pressure in the shaft passage 12 (hereinafter sometimes referred to as the oil pressure in the shaft passage 12), and transmits the detection result to the control device 50. The pressure sensor 42 according to the present embodiment detects the oil pressure in the shaft passage 12 at the right end of the inner shaft 10. However, the arrangement location of the pressure sensor 42 is not limited to this as long as the oil pressure in the shaft passage 12 can be detected.

  The control device 50 includes a control unit that executes control processing and arithmetic processing, and a storage unit that stores information necessary for the operation of the control unit. As the control device 50, an electronic control unit (Electronic Control Unit) can be used. In this embodiment, an electronic control device including a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, and a RAM (Random Access Memory) 53 is used as an example of the control device 50. The function of the control unit can be realized by the CPU 51. The function of the storage unit can be realized by the ROM 52 and the RAM 53. The control unit of the control device 50 controls the variable valve operating device 5 and also controls the operation of the internal combustion engine (specifically, fuel injection timing, ignition timing, etc.).

  FIG. 2A is a schematic cross-sectional view in which the vicinity of the # 1 cylinder 100 of the variable valve apparatus 5 is enlarged. In this embodiment, the shaft passage 12 has a large inner diameter from the upstream side (left side) in the oil flow direction to the vicinity of the cam journal 120 disposed between the valves 110 of the # 1 cylinder 100, and thereafter the inner diameter is increased. It is getting thinner. However, the configuration of the shaft passage 12 is not limited to this. For example, the inner diameter of the shaft passage 12 may be uniform from the upstream side to the downstream side in the oil flow direction.

  Details of the configuration of the outer cam 20 will be described with reference to FIG. The outer cam 20 of the cylinders # 2 to # 4 has the same configuration as the outer cam 20 of the cylinder 100 of # 1. Therefore, the details of the configuration of the outer cam 20 of the # 1 cylinder 100 will be described, and the detailed description of the configuration of the outer cam 20 of the # 2 to # 4 cylinder 100 will be omitted. As described above in FIG. 1A, the outer cam 20 has a plurality of cams having different cam profiles as cams corresponding to the valve 110 of the internal combustion engine. The number of the plurality of cams is not particularly limited as long as it is 2 or more. The outer cam 20 according to the present embodiment includes two types of cams as a plurality of cams having different cam profiles. The outer cam 20 includes a first cam and a second cam having a cam profile different from that of the first cam as two types of cams.

  Specifically, the outer cam 20 according to the present embodiment includes a small cam 21 as a first cam and a large cam 22 as a second cam. The cam profile of the small cam 21 is such that the valve 110 is not lifted by the small cam 21 or the lift amount of the valve 110 driven by the small cam 21 is smaller than the lift amount of the valve 110 driven by the large cam 22. Cam profile.

  When the cam profile of the small cam 21 is a cam profile in which the valve 110 is not lifted by the small cam 21, when the small cam 21 is in a position corresponding to the valve 110 as shown in FIG. Can be stopped. That is, in this case, the variable valve gear 5 can perform a so-called cylinder stop operation.

  In this embodiment, a cam profile in which the lift amount of the valve 110 driven by the small cam 21 is smaller than the lift amount of the valve 110 driven by the large cam 22 is used as an example of the cam profile of the small cam 21. In this case, the axial position of the outer cam 20 with respect to the inner shaft 10 is displaced between a position where the small cam 21 corresponds to the valve 110 and a position where the large cam 22 corresponds to the valve 110, thereby The lift amount can be changed between a small lift amount and a large lift amount.

  In this embodiment, since the internal combustion engine includes two valves 110 per cylinder 100, the outer cam 20 includes two small cams 21 and two large cams 22 per cylinder 100. Specifically, the outer cam 20 includes a small cam 21 and a large cam 22 corresponding to one of the two valves 110 arranged in one cylinder 100, and a small cam 21 and a corresponding to the other valve 110. And a large cam 22.

  Therefore, the outer cam 20 includes a small cam 21 corresponding to one valve 110 (specifically, the left valve 110) and a large cam 22 corresponding to the other valve 110 (specifically, the right valve 110). It has the connection part 23 to connect. The outer peripheral surface 24 of the connecting portion 23 (note that the reference numeral of the outer peripheral surface 24 is shown in FIG. 2B described later) is pivotally supported by the cam journal 120.

  The outer cam 20 includes a groove forming portion 28 having a groove 27 formed on the outer peripheral surface. The groove forming portion 28 according to the present embodiment is connected to the right side surface of the right small cam 21. The groove 27 is configured such that the outer cam 20 is displaced with respect to the axial direction when a groove engaging member 31 described later of the displacement mechanism 30 is engaged. When the outer cam 20 is displaced in the axial direction, the cam corresponding to the valve 110 can be switched between the small cam 21 and the large cam 22.

  Specifically, the cam corresponding to the valve 110 can be switched to the large cam 22 by the outer cam 20 being displaced from the state of FIG. Further, the cam corresponding to the valve 110 can be switched to the small cam 21 by the outer cam 20 being displaced leftward in the axial direction from the position where the large cam 22 corresponds to the valve 110. Details of the groove 27 will be described later with reference to FIG.

  FIG. 2B is a schematic cross-sectional view enlarging the vicinity of the connecting portion 23 of the outer cam 20. The connecting portion 23 is formed with a passage (referred to as an oil communication passage) that connects the shaft passage 12 and the outer peripheral surface 24 of the connecting portion 23. Specifically, the oil communication path according to the present embodiment includes a small communication path 25 and a large communication path 26.

  The small continuous passage 25 is disposed on the right side of the large continuous passage 26. Specifically, the small communication path 25 is a position where the shaft path 12 and the outer peripheral surface 24 communicate with each other when the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is a position where the small cam 21 corresponds to the valve 110. Is set. The Dalian passage 26 is set to a position where the shaft passage 12 and the outer peripheral surface 24 communicate with each other when the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is a position where the large cam 22 corresponds to the valve 110. .

The passage area of the small continuous passage 25 is set smaller than the passage area of the large continuous passage 26. Specifically, the small continuous passage 25 and the large continuous passage 26 are configured by holes whose depth direction is a direction perpendicular to the axial direction of the connecting portion 23 (the vertical direction in FIG. 2B). The sectional area of the hole of the small passage 25 is set smaller than the sectional area of the hole of the large passage 26. Thereby, the passage area of the small continuous passage 25 is smaller than the passage area of the large continuous passage 26. Since the passage area of the small continuous passage 25 is smaller than the passage area of the large continuous passage 26, the flow rate (m ³ / s) of oil passing through the small continuous passage 25 is smaller than the flow rate of oil passing through the large continuous passage 26. .

  That is, in the outer cam 20 according to the present embodiment, the small passage 25 having a relatively small passage area communicates the shaft passage 12 and the outer peripheral surface 24 in accordance with the position of the outer cam 20 in the axial direction with respect to the inner shaft 10. The state and the state where the Dalian passage 26 having a relatively large passage area communicates with the shaft passage 12 and the outer peripheral surface 24 are switched. As a result, the variable valve apparatus 5 has a configuration in which the passage area of the oil communication passage that communicates the shaft passage 12 and the outer peripheral surface 24 changes according to the position of the outer cam 20 in the axial direction relative to the inner shaft 10. Yes.

  Since the passage area of the small continuous passage 25 is set smaller than the passage area of the large continuous passage 26, the small continuous passage 25 is located at the position of the shaft passage 12 (that is, the small cam 21 corresponds to the valve 110). The oil pressure in the shaft passage 12 is lower than the oil pressure in the shaft passage 12 when the Dalian passage 26 is located at the position of the shaft passage 12 (that is, when the large cam 22 corresponds to the valve 110).

  When the small communication passage 25 communicates the shaft passage 12 and the outer peripheral surface 24, the oil of the inner shaft 10 passes through the small communication passage 25 and is supplied to the outer peripheral surface 24. When the Dalian passage 26 communicates with the shaft passage 12 and the outer peripheral surface 24, the oil of the inner shaft 10 passes through the Dalian passage 26 and is supplied to the outer peripheral surface 24.

  In the variable valve operating apparatus 5 according to the present embodiment, when the outer cam 20 is displaced in the axial direction, the outer peripheral surface 24 of the outer cam 20 (specifically, the outer peripheral surface 24 of the connecting portion 23) is the inner periphery of the cam journal 120. The outer cam 20 and the cam journal 120 are moved by the oil supplied to the outer peripheral surface 24 of the outer cam 20 from the oil communication path (the small communication path 25 or the large communication path 26). Lubricating between is ensured. In particular, the small passage 25 and the large passage 26 according to the present embodiment are formed so as to correspond to the portion of the outer peripheral surface 24 of the connecting portion 23 of the outer cam 20 that is pivotally supported by the cam journal 120. The oil that has passed through the small path 25 and the large path 26 is effectively supplied between the inner peripheral surface of the cam journal 120 and the surface of the outer cam 20 that is pivotally supported by the cam journal 120 (that is, the outer peripheral surface 24). be able to. As a result, according to the variable valve operating apparatus 5, lubrication between the outer cam 20 and the cam journal 120 is effectively ensured.

  2A, the displacement mechanism 30 includes a groove engaging member 31 that can be engaged with the groove 27 formed in the groove forming portion 28 of the outer cam 20, and a drive that drives the groove engaging member 31. Part 32. The specific configuration of the groove engaging member 31 is not particularly limited as long as it can engage with the groove 27. The groove engaging member 31 according to the present embodiment is a rod-shaped pin.

  The drive unit 32 is a device that drives the groove engaging member 31 in response to an instruction from the control device 50. Specifically, the drive unit 32 causes the groove engaging member 31 to appear in and out of the drive unit 32 in response to an instruction from the control unit of the control device 50. When the groove engaging member 31 is engaged with the groove 27, the control unit gives an instruction to the driving unit 32 so that the groove engaging member 31 protrudes from the driving unit 32. When ending the engagement of the groove engaging member 31 with the groove 27, the control unit gives an instruction to the driving unit 32 so that the groove engaging member 31 is immersed in the driving unit 32. As described above, the control unit according to the present embodiment controls the driving unit 32 of the displacement mechanism 30, and the driving unit 32 drives the groove engaging member 31 in response to an instruction from the control unit. The control unit obtains the angle with respect to the crank angle of the inner shaft 10 based on the detection results of the cam position sensor 41 and the crank position sensor 40, thereby grasping the position of the groove 27 in the rotational direction, and the groove engaging member 31. The position of the groove 27 to be engaged is grasped.

  The drive unit 32 is supported by a predetermined portion of the internal combustion engine so that the drive unit 32 does not move in the axial direction of the inner shaft 10 when the groove engaging member 31 is engaged with the groove 27. The predetermined portion of the internal combustion engine that supports the drive unit 32 is not particularly limited, and a cylinder head, a cylinder head cover, or the like of the internal combustion engine can be used. It is assumed that the drive unit 32 according to the present embodiment is supported by the internal combustion engine so as to be fixed to the cylinder head. The specific configuration of the drive unit 32 is not particularly limited, but in this embodiment, an electric actuator is used as an example. A solenoid actuator is used as an example of an electric actuator.

  Moreover, the variable valve operating apparatus 5 includes a locking mechanism 60 as a mechanism for suppressing the axial position of the outer cam 20 relative to the inner shaft 10 from being displaced after the cam switching. FIG. 2C is a schematic cross-sectional view for explaining the locking mechanism 60. The locking mechanism 60 includes a first recess 61 and a second recess 62 formed on a surface of the outer cam 20 facing the inner shaft 10, an engagement portion 63 that engages with these recesses, and an engagement portion 63. And a biasing member 64 for biasing.

  The urging member 64 is disposed in the accommodation hole 65 provided in the inner shaft 10. The housing hole 65 and the shaft passage 12 are configured not to interfere with each other. Specifically, the accommodation hole 65 according to the present embodiment is formed at a position that does not interfere with the shaft passage 12. Thereby, the oil of the shaft passage 12 is suppressed from leaking into the accommodation hole 65.

  The engaging portion 63 is connected to the urging member 64 and is urged by the urging member 64 in a direction perpendicular to the axial direction of the inner shaft 10 (upward in FIG. 2C). The accommodation hole 65 is set to be larger than the diameter of the engaging portion 63.

  In this embodiment, a spring is used as an example of the urging member 64. However, the configuration of the urging member 64 is not limited to the spring as long as it can urge the engaging portion 63. In this embodiment, a sphere is used as an example of the engaging portion 63. However, the configuration of the engaging portion 63 is not limited to a sphere as long as it can engage with the first concave portion 61 and the second concave portion 62.

  The first recess 61 is located on the right side in the axial direction with respect to the second recess 62. The positions of the first recess 61, the second recess 62, and the engagement portion 63 correspond to the valve 110 when the cam corresponding to the valve 110 is the small cam 21 and the engagement portion 63 is engaged with the first recess 61. When the cam is the large cam 22, the engaging portion 63 is set to engage with the second recess 62.

  Moreover, the 1st recessed part 61 is provided with the 1st inclined surface 66 inclined with respect to the axial direction. The second recess 62 includes a second inclined surface 67 that is inclined with respect to the axial direction. The first inclined surface 66 is a surface that decomposes the force from the engaging portion 63 urged by the urging member 64 into a left component in the axial direction. The 2nd inclined surface 67 is a surface which decomposes | disassembles the force from the engaging part 63 urged | biased by the urging | biasing member 64 into the component of the right direction in an axial direction.

  FIGS. 3A and 3B are schematic cross-sectional views showing how the outer cam 20 is displaced in the axial direction. Specifically, FIG. 3A is an enlarged schematic sectional view of a part of the variable valve gear 5 when the outer cam 20 is displaced to a position where the small cam 21 corresponds to the valve 110. FIG. 3B is an enlarged schematic sectional view of a part of the variable valve gear 5 when the outer cam 20 is displaced to a position where the large cam 22 corresponds to the valve 110.

  Referring to FIG. 3A, when the cam corresponding to the valve 110 is the small cam 21, the small communication path 25 of the outer cam 20 communicates the shaft path 12 and the outer peripheral surface 24 of the outer cam 20. Referring to FIG. 3B, when the cam corresponding to the valve 110 is the large cam 22, the large passage 26 of the outer cam 20 communicates the shaft passage 12 and the outer peripheral surface 24 of the outer cam 20.

  Referring to FIG. 3A, when the cam corresponding to the valve 110 is the small cam 21, the engaging portion 63 urged by the urging member 64 abuts on the first inclined surface 66 of the first recess 61. ing. In this case, the outer cam 20 receives a leftward force in the axial direction from the engaging portion 63. As a result, the left side surface of the large cam 22 of the outer cam 20 (specifically, the large cam 22 corresponding to the right valve 110) contacts the cam journal 120. Thereby, the axial position of the outer cam 20 with respect to the inner shaft 10 is prevented from changing. As a result, the positional relationship between the small cam 21 and the valve 110 is suppressed from shifting.

  In order to switch the cam corresponding to the valve 110 from the small cam 21 to the large cam 22, when the outer cam 20 moves rightward in the axial direction from the state of FIG. It is accommodated in the accommodation hole 65 so as to be pushed by the portion between the first recess 61 and the second recess 62. As a result, the engaging part 63 is detached from the first recess 61. Thereafter, as shown in FIG. 3B, when the movement of the outer cam 20 in the axial direction is completed and the cam corresponding to the valve 110 is switched to the large cam 22, the engaging portion 63 is moved from the biasing member 64. The urging force of the second recess 62 protrudes from the receiving hole 65 and contacts the second inclined surface 67 of the second recess 62.

  When the engaging portion 63 urged by the urging member 64 contacts the second inclined surface 67 of the second recess 62, the outer cam 20 receives a rightward force in the axial direction from the engaging portion 63. As a result, the right side surface of the small cam 21 of the outer cam 20 (specifically, the small cam 21 corresponding to the left valve 110) contacts the cam journal 120. Thereby, the axial position of the outer cam 20 with respect to the inner shaft 10 is prevented from changing. As a result, the positional relationship between the large cam 22 and the valve 110 is suppressed from shifting.

  In this manner, the locking mechanism 60 suppresses the axial displacement of the outer cam 20 with respect to the inner shaft 10 after the cam switching is completed. If the mechanism is capable of suppressing the axial displacement of the outer cam 20 with respect to the inner shaft 10 after the cam switching is completed, the variable valve gear 5 has a configuration other than the locking mechanism 60 as in the present embodiment. May be.

  FIG. 4A is a schematic diagram for explaining the details of the groove 27. Specifically, FIG. 4A schematically illustrates a state in which the groove 27 is developed in the circumferential direction of the groove forming portion 28. In FIG. 4A, the rotation direction of the inner shaft 10 and the outer cam 20 is upward. The groove 27 has a structure in which the cam corresponding to the valve 110 is switched between the small cam 21 and the large cam 22 when the groove engaging member 31 engages with the groove 27.

  Specifically, the groove 27 has a first vertical portion 70, a second vertical portion 72, and a third vertical portion 74 having a groove direction perpendicular to the axial direction of the inner shaft 10. Further, the groove 27 has a first inclined portion 71 and a second inclined portion 73 having a groove direction inclined with respect to the axial direction. The first vertical portion 70, the first inclined portion 71, the second vertical portion 72, the second inclined portion 73, and the third vertical portion 74 are connected in this order.

  When the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21, the groove engaging member 31 is sequentially engaged with the first vertical portion 70, the first inclined portion 71, and the second vertical portion 72. When the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22, the groove engaging member 31 is sequentially engaged with the second vertical portion 72, the second inclined portion 73, and the third vertical portion 74.

  FIG. 4B to FIG. 4D are schematic diagrams for explaining an engagement mode of the groove engaging member 31 to the groove 27. 4B to 4D schematically show how the groove engaging member 31 is engaged with the groove 27, and the cam corresponding to the valve 110 is switched on the lower stage. The situation is schematically illustrated.

  As shown in FIG. 4B, when the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21, the control unit of the control device 50 is configured such that the groove engaging member 31 protrudes from the driving unit 32. An instruction is given to the drive unit 32 to engage with any part of the vertical part 70. The groove engaging member 31 engaged with the first vertical portion 70 moves relative to the groove 27 as the inner shaft 10 and the outer cam 20 rotate.

  As shown in FIG. 4C, when the groove engaging member 31 is engaged with the first inclined portion 71, the outer cam 20 is moved to the left side by the axial force that the first inclined portion 71 receives from the groove engaging member 31. Move to. As shown in FIG. 4D, the movement of the outer cam 20 in the axial direction ends the engagement of the groove engaging member 31 with the first inclined portion 71 and starts the engagement with the second vertical portion 72 as shown in FIG. Continue until When the groove engaging member 31 is engaged with the second vertical portion 72, the control unit gives an instruction to the driving unit 32 so that the groove engaging member 31 is immersed in the driving unit 32. As a result, the engagement of the groove engaging member 31 with the groove 27 ends. The first vertical portion 70, the first inclined portion 71, and the second vertical portion 72 so that the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21 until the outer cam 20 makes one rotation. The circumferential length of the groove forming portion 28 is set.

  On the other hand, when the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22 (illustration is omitted), the control unit is configured so that the groove engaging member 31 protrudes from the drive unit 32 and any one of the second vertical portions 72 An instruction is given to the drive unit 32 so as to engage with the position. The groove engaging member 31 engaged with the second vertical portion 72 moves relative to the groove 27 as the inner shaft 10 and the outer cam 20 rotate. When the groove engaging member 31 is engaged with the second inclined portion 73, the outer cam 20 moves to the right side by the axial force received by the second inclined portion 73 from the groove engaging member 31. The movement of the outer cam 20 in the axial direction is continued until the groove engaging member 31 finishes engaging the second inclined portion 73 and starts engaging the third vertical portion 74. When the groove engaging member 31 is engaged with the third vertical portion 74, the control unit ends the engagement of the groove engaging member 31 with the groove 27 by immersing the groove engaging member 31 into the drive unit 32. . The second vertical portion 72, the second inclined portion 73, and the third vertical portion 74 so that the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22 until the outer cam 20 makes one rotation. The circumferential length of the groove forming portion 28 is set.

  As described above, the groove 27 according to the present embodiment has a structure in which the cam corresponding to the valve 110 is switched between the small cam 21 and the large cam 22 when the groove engaging member 31 is engaged with the groove 27. doing. The groove 27 is not limited to the structure shown in FIG. 4A as long as the cam corresponding to the valve 110 can be switched by engaging the groove engaging member 31 with the groove 27. . Further, the displacement mechanism 30 according to this embodiment is a mechanism that displaces the outer cam 20 relative to the inner shaft 10 in the axial direction of the inner shaft 10 by engaging the groove engaging member 31 with the groove 27 of the outer cam 20. However, the configuration of the displacement mechanism 30 is not limited to the above-described mechanism as long as the outer cam 20 can be displaced relative to the inner shaft 10 in the axial direction of the inner shaft 10.

  Next, details of the control device 50 will be described. The control unit of the control device 50 controls the displacement mechanism 30 of the variable valve operating device 5 as described above when the cam corresponding to the valve 110 is switched between the small cam 21 and the large cam 22. The specific contents of the conditions for switching the cam corresponding to the valve 110 between the small cam 21 and the large cam 22 (hereinafter sometimes referred to as cam switching conditions) are not particularly limited. Appropriate conditions may be set according to the cam profiles of the cam 21 and the large cam 22.

  The control unit according to the present embodiment uses whether or not the load of the internal combustion engine is equal to or greater than a predetermined load as an example of the cam switching condition. Specifically, the control unit gives an instruction to the drive unit 32 of the displacement mechanism 30 so that the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22 when the load is a predetermined load or more. When the load is smaller than the predetermined load, the drive unit 32 is instructed so that the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21.

  As an example of the load of the internal combustion engine, the rotational speed of the internal combustion engine, the fuel injection amount, the intake air amount, and the like can be used. In this embodiment, the rotational speed of the internal combustion engine is used as an example of the load. In this case, the control unit acquires the rotational speed (rpm) of the internal combustion engine based on the detection result of the crank position sensor 40, and when the acquired rotational speed is equal to or greater than a predetermined value, the cam that drives the valve 110 is a large cam. The displacement mechanism 30 is controlled so as to be 22, and when the rotational speed is smaller than a predetermined value, the displacement mechanism 30 is controlled so that the cam that drives the valve 110 becomes the small cam 21. The specific value of the predetermined value is not particularly limited, and may be set as appropriate according to the cam profiles of the small cam 21 and the large cam 22. The predetermined value of the rotational speed is stored in advance in the storage unit.

  The control unit detects the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12. As described above with reference to FIG. 2B, the variable valve apparatus 5 is configured so that the passage area of the oil communication passage that connects the shaft passage 12 and the outer peripheral surface 24 depends on the position of the outer cam 20 in the axial direction relative to the inner shaft 10. The configuration changes. Thereby, when the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 changes, as a result of the change in the passage area of the oil communication passage, the oil pressure in the shaft passage 12 also changes. Therefore, the control unit can detect the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12.

  Further, when the controller according to the present embodiment detects the position of the outer cam 20 in the axial direction relative to the inner shaft 10, the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is further based on the oil pressure in the shaft passage 12. It is also determined whether or not is abnormal. Hereinafter, control for detecting the position of the outer cam 20 in the axial direction relative to the inner shaft 10 and determining whether or not the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal will be described. This is called abnormality determination control.

  In addition, the control unit according to the present embodiment controls the cam corresponding to the valve 110 to switch among the plurality of cams by controlling the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10. (Hereinafter, sometimes referred to as cam switching control), the operating state change control is executed to change the operating state of the internal combustion engine in accordance with the type of cam corresponding to the valve 110 after the cam switching control. .

  Details of the cam position detection abnormality determination control and the operation state change control will be described below. First, details of the cam position detection abnormality determination control will be described. In the cam position detection abnormality determination control, the control unit according to the present embodiment acquires the oil pressure of the shaft passage 12 based on the detection result of the pressure sensor 42, and uses the acquired oil pressure of the shaft passage 12 as a predetermined reference pressure. By comparing, the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is detected, and whether there is an abnormality in the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is determined. First, a predetermined reference pressure (hereinafter sometimes referred to as a reference pressure of the shaft passage 12) will be described.

  In the storage unit of the control device 50 according to the present embodiment, the reference pressure of the shaft passage 12 is stored in advance as a map. In this map, the reference pressure of the shaft passage 12 is defined in association with an index indicating the operating state of the internal combustion engine. The index indicating the operating state of the internal combustion engine is not particularly limited. For example, the rotational speed of the internal combustion engine, the fuel injection amount, the intake air amount, the temperature of the combustion chamber, and the like can be used. In this embodiment, the number of revolutions of the internal combustion engine is used as an example of an index indicating the operating state of the internal combustion engine. That is, in the present embodiment, as an example of the map, the reference pressure in the shaft passage 12 is defined in association with the rotational speed of the internal combustion engine.

  FIG. 5 is a diagram for explaining a map of the reference pressure of the shaft passage 12 used in the cam position detection abnormality determination control according to the present embodiment. Specifically, FIG. 5 shows an example of a map of the reference pressure of the shaft passage 12 visualized. The horizontal axis in FIG. 5 indicates the rotational speed (rpm) of the internal combustion engine, and the vertical axis indicates the oil pressure (Pa) in the shaft passage 12. In FIG. 5, a curve 200, a curve 201, a curve 202, and a curve 203 are shown. These curves 200 to 203 are curves such that the oil pressure in the shaft passage 12 increases as the rotational speed increases. The curve 203 is located above the curve 202, the curve 200 is located above the curve 203, and the curve 201 is located above the curve 200.

  In FIG. 5, a virtual curve 220 is shown in the middle between the curve 200 and the curve 201. The curve 200 is positioned below the virtual curve 220 by a predetermined pressure, and the curve 201 is positioned above the virtual curve 220 by a predetermined pressure. An imaginary curve 221 is shown between the curve 202 and the curve 203. The curve 202 is positioned below the virtual curve 221 by a predetermined pressure, and the curve 203 is positioned above the virtual curve 221 by a predetermined pressure.

  An area 210 between the curve 200 and the curve 201 (that is, an area between the curve 200 and the curve 201) is a target position in the axial direction of the outer cam 20 with respect to the inner shaft 10 (hereinafter, this may be referred to as a target cam position). The reference pressure (Po (small)) of the shaft passage 12 used when the small cam 21 is at a position corresponding to the valve 110 is stored. From another viewpoint, the area 210 stores the reference pressure (Po (small)) of the shaft passage 12 used when the small communication passage 25 communicates the shaft passage 12 and the outer peripheral surface 24 of the outer cam 20. Has been.

  In a region 211 between the curves 202 and 203 (that is, a region between the curve 202 and the curve 203), the target cam position is the position of the shaft passage 12 used when the large cam 22 is a position corresponding to the valve 110. A reference pressure (Po (large)) is stored. From another viewpoint, the region 211 stores the reference pressure (Po (large)) of the shaft passage 12 used when the dalian passage 26 communicates the shaft passage 12 and the outer peripheral surface 24 of the outer cam 20. ing.

  The control unit acquires the oil pressure in the shaft passage 12 based on the detection result of the pressure sensor 42. When the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21, and when the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22, the control unit is configured to detect the internal combustion engine based on the detection result of the crank position sensor 40. The rotation speed is acquired, and the reference pressure of the shaft passage 12 corresponding to the acquired rotation speed is acquired from the map of the storage unit (FIG. 5).

  Specifically, when the rotation number acquired by the control unit is, for example, A (rpm), the control unit acquires the upper limit value and the lower limit value of the oil pressure corresponding to the rotation number A in the region 210, and the region 211 Among these, an upper limit value and a lower limit value of the oil pressure corresponding to the rotation speed A are acquired.

  Specifically, the control unit obtains the oil pressure (Po (small) max) of the curve 201 corresponding to the rotation speed A as the upper limit value of the oil pressure corresponding to the rotation speed A in the area 210, The oil pressure (Po (small) min) of the curve 200 corresponding to the rotation speed A is acquired as the lower limit value of the oil pressure corresponding to the rotation speed A. In addition, the control unit obtains the oil pressure (Po (large) max) of the curve 203 corresponding to the rotation speed A as the upper limit value of the oil pressure corresponding to the rotation speed A in the area 211, and the oil pressure corresponding to the area 211. The oil pressure (Po (large) min) of the curve 202 corresponding to the rotational speed A is acquired as the lower limit value of.

  The control unit detects the pressure sensor 42 when the axial target position of the outer cam 20 with respect to the inner shaft 10 (that is, the target cam position) is set to a position corresponding to the valve 110 of the small cam 21. If the oil pressure of the shaft passage 12 acquired based on the result falls within the range of Po (small) min to Po (small) max (that is, the range of the region 210), the outer cam 20 with respect to the inner shaft 10 It is detected that the small cam 21 is at a position corresponding to the valve 110 in the axial direction. In this case, the control unit determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is normal.

  On the other hand, when the target cam position is set to a position where the small cam 21 corresponds to the valve 110, the control unit determines that the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is Po (small). ) When not in the range of min to Po (small) max (region 210), the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the small cam 21 corresponds to the valve 110. Detect not. In this case, the control unit determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is abnormal. That is, the control unit detects an abnormality in the position of the outer cam 20 in the axial direction with respect to the inner shaft 10.

  In addition, when the target cam position is set to a position where the large cam 22 corresponds to the valve 110, the control unit determines that the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is Po (large) min. As long as it is within the range of Po (large) max or less (that is, the range of the region 211), the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the large cam 22 corresponds to the valve 110. Detect that. In this case, the control unit determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is normal.

  On the other hand, when the target cam position is set to a position where the large cam 22 corresponds to the valve 110, the control unit determines that the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is the Po (high). ) When not in the range from min to Po (large) max (range 211), the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the large cam 22 corresponds to the valve 110. Detect not. In this case, the control unit determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is abnormal.

  As described above, the control unit according to the present embodiment is stored in the storage unit and the oil pressure of the shaft passage 12 (measured value of the oil pressure in the shaft passage 12) acquired based on the detection result of the pressure sensor 42. The axial position of the outer cam 20 detected based on the reference pressure of the shaft passage 12 with respect to the inner shaft 10 is a predetermined cam selected from a plurality of cams that the outer cam 20 has a cam corresponding to the valve 110. If it is different from the instruction (setting of the target cam position), it is determined that the axial position of the outer cam 20 with respect to the inner shaft 10 is abnormal. In this way, the control unit detects an abnormality in the position of the outer cam 20 in the axial direction with respect to the inner shaft 10.

  When the controller determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal, the control unit controls the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10. The cam corresponding to the valve 110 is switched. And a control part performs cam position detection abnormality determination control again.

  Specifically, the control unit determines that the axial position of the outer cam 20 relative to the inner shaft 10 is abnormal when the target cam position is set to a position corresponding to the valve 110 of the small cam 21. In this case, the cam corresponding to the valve 110 is switched to the large cam 22 by controlling the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10. Then, the control unit determines whether or not the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is within the range 211 of the map.

  As a result, if the oil pressure in the shaft passage 12 is within the range 211 of the map, the control unit determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the large cam 22 corresponds to the valve 110. It is determined that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is normal. On the other hand, if the oil pressure in the shaft passage 12 does not fall within the range 211 of the map, the control unit sets the position of the outer cam 20 in the axial direction relative to the inner shaft 10 to the position where the large cam 22 corresponds to the valve 110. It is determined that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal.

  Similarly, the control unit determines that the axial position of the outer cam 20 relative to the inner shaft 10 is abnormal when the target cam position is set to a position corresponding to the valve 110 of the large cam 22. In this case, the cam corresponding to the valve 110 is switched to the small cam 21 by controlling the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10. Then, the control unit determines whether or not the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is within the range 210 of the map.

  As a result, if the oil pressure in the shaft passage 12 is within the range 210 of the map, the control unit sets the position of the outer cam 20 in the axial direction relative to the inner shaft 10 to the position where the small cam 21 corresponds to the valve 110. It is determined that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is normal. On the other hand, if the oil pressure in the shaft passage 12 does not fall within the range 210 of the map, the control unit sets the position of the outer cam 20 in the axial direction relative to the inner shaft 10 to the position where the small cam 21 corresponds to the valve 110. It is determined that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal.

  In the map of FIG. 5, the reference pressure of the shaft passage 12 is predetermined as shown in a region 210 (region between the curve 200 and the curve 201) and a region 211 (region between the curve 202 and the curve 203). Although it is defined with a width, it is not limited to this. For example, the map is based on a virtual curve 220 that is an intermediate curve between the curve 200 and the curve 201, and the reference pressure (Po (small) of the shaft passage 12 used when the target cam position is a position corresponding to the valve 110 of the small cam 21. )), And a virtual curve 221 that is an intermediate curve between the curve 202 and the curve 203 is set to a reference pressure (Po ( Large)).

  However, since it is considered that a predetermined variation occurs in the oil pressure of the shaft passage 12, the reference pressure of the shaft passage 12 is defined with a predetermined width as in the region 210 and the region 211 as in this embodiment. This is preferable in that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 and the presence / absence of an abnormality can be detected in consideration of variations in the oil pressure in the shaft passage 12.

  FIG. 6 is a diagram illustrating an example of a flowchart when the control device 50 according to the present embodiment executes cam position detection abnormality determination control. The control unit of the control device 50 repeatedly executes the flowchart of FIG. 6 every predetermined period. First, the control unit acquires the oil pressure (P) of the shaft passage 12 based on the detection result of the pressure sensor 42 (step S10).

  Next, the control unit sets a target cam position that is a target position in the axial direction of the outer cam 20 with respect to the inner shaft 10 (step S11). The control unit according to the present embodiment sets the target cam position in a predetermined part (for example, a storage unit) of the control device 50 based on the cam switching condition described above. Specifically, the control unit sets the axial position of the outer cam 20 such that the large cam 22 corresponds to the valve 110 as the target cam position when the rotational speed of the internal combustion engine is equal to or greater than a predetermined value. Further, when the rotational speed of the internal combustion engine is smaller than a predetermined value, the control unit sets the position in the axial direction of the outer cam 20 such that the small cam 21 corresponds to the valve 110 as the target cam position.

  Next, the control unit determines whether or not the target cam position set in step S11 is a position where the small cam 21 corresponds to the valve 110 (step S12). That is, step S12 is a process for confirming whether or not an instruction (setting) to make the cam corresponding to the valve 110 the small cam 21 is made. When it is determined in step S <b> 12 that the target cam position is a position corresponding to the valve 110 for the small cam 21 (that is, when it is determined Yes), the control unit corresponds to the small cam 21 in the reference pressure of the shaft passage 12. The obtained reference pressure (Po (small)) is acquired (step S13). Specifically, the control unit acquires the rotational speed of the internal combustion engine, and acquires Po (small) min and Po (small) max corresponding to the rotational speed from the area 210 of the map shown in FIG.

  Next, the control unit determines whether or not the oil pressure P of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is included in the range of Po (small) min to Po (small) max (step). S14).

  When it is determined in step S14 that the oil pressure P of the shaft passage 12 is included in the range of Po (small) min or more and Po (small) max or less (that is, when it is determined Yes), the control unit sets the outer cam. 20, the position (cam position) in the axial direction with respect to the inner shaft 10 is detected to be a position corresponding to the valve 110, and the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is normal. It is determined that there is (step S15). Next, the control unit ends the execution of the flowchart.

  When it determines with No by step S14, while a control part detects that the position of the axial direction of the outer cam 20 with respect to the inner shaft 10 is not the position where the small cam 21 corresponds to the valve 110, the outer cam 20 It is determined that the axial position with respect to the inner shaft 10 is abnormal (step S16).

  Next, the control unit controls the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10 in order to switch the cam corresponding to the valve 110 from the current cam to another cam (step S17). ). Next, the control unit executes Step S11. In step S11 executed after step S17, the position of the outer cam 20 in the axial direction such that the large cam 22 corresponds to the valve 110 is set as the target cam position. As a result, No is determined in step S12.

  When it is determined No in step S12 (in this case, the target cam position is set to a position where the large cam 22 corresponds to the valve 110), the control unit corresponds to the large cam 22 in the reference pressure of the shaft passage 12. The obtained reference pressure (Po (large)) is acquired (step S18). Specifically, the control unit acquires the rotational speed of the internal combustion engine, and acquires Po (large) min and Po (large) max corresponding to the rotational speed from the region 211 of the map shown in FIG.

  Next, the control unit determines whether or not the oil pressure P of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is included in a range of Po (large) min to Po (large) max (step). S19). When it is determined in step S19 that the oil pressure P of the shaft passage 12 is included in the range of Po (large) min to Po (large) max (ie, determined to be Yes), the control unit sets the outer cam. 20 detects that the position of the large cam 22 in the axial direction relative to the inner shaft 10 is the position corresponding to the valve 110, and determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is normal. (Step S20). Next, the control unit ends the execution of the flowchart.

  When it determines with No by step S19, while a control part detects that the position of the axial direction of the outer cam 20 with respect to the inner shaft 10 is not the position where the large cam 22 corresponds to the valve 110, the outer cam 20 It determines with the position of the axial direction with respect to the inner shaft 10 being abnormal (step S21).

  Next, the control unit controls the displacement mechanism 30 so that the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10 in order to switch the cam corresponding to the valve 110 from the current cam to another cam (step S22). ). Next, the control unit executes Step S11. In step S11 executed after step S22, the position of the outer cam 20 in the axial direction such that the small cam 21 corresponds to the valve 110 is set as the target cam position. As a result, Yes is determined in step S12.

  Step S11, Step S12, Step S18, Step S19 are executed after Step S17 is executed, and Step S21 is executed. After Step S22 is executed, Step S11, Step S12, Step S13, Step When S14 is executed and step S16 is executed, the oil pressure in the shaft passage 12 does not belong to any of the regions 210 and 211 in the map of FIG. In this case, it is conceivable that some abnormality has occurred in the internal combustion engine or the variable valve gear 5.

  Therefore, when step S21 is executed after execution of step S17 described above and when step S16 is executed after execution of step S22, the control unit performs alarm notification control for notifying the user of the internal combustion engine of an alarm. It is preferable to carry out. Actually, the control unit according to the present embodiment executes the alarm notification control. In this case, a notification device (for example, a lamp, a speaker, etc.) for notifying the user of an alarm is disposed in the driver's seat of the vehicle on which the internal combustion engine is mounted. A control part alert | reports a warning to a user by controlling this alerting | reporting apparatus. Thereby, the user can know that an abnormality has occurred in the internal combustion engine or the variable valve gear 5. After executing the alarm notification control, the control unit forcibly ends the execution of the flowchart.

  Next, details of the operation state change control executed by the control unit will be described. As described above, the control unit according to the present embodiment executes the operation state change control when the cam switching control for switching the cam corresponding to the valve 110 among the plurality of cams by controlling the displacement mechanism 30 is performed. To do. In the operation state change control, the control unit changes the operation state of the internal combustion engine according to the type of cam corresponding to the valve 110 after the cam switching control is executed.

  Specifically, in the operation state change control, the control unit changes at least one of the fuel injection amount and the ignition timing of the internal combustion engine according to the type of cam corresponding to the valve 110 after the cam switching control is executed. As an example of the operation state change control, the control unit according to the present embodiment changes both the fuel injection amount and the ignition timing of the internal combustion engine according to the type of cam corresponding to the valve 110 after the cam switching control is executed. Specifically, after the cam switching control is executed, the control unit determines the fuel injection amount and the ignition timing from the fuel injection amount and ignition timing used before the cam is switched and the fuel injection amount corresponding to the current cam. Change to ignition timing.

  In executing the operation state change control, the storage unit of the control device 50 corresponds to the fuel injection amount and ignition timing map (hereinafter referred to as the first operation state map) corresponding to the small cam 21 and the large cam 22. A map of the fuel injection amount and the ignition timing (hereinafter referred to as a second operation state map) is stored in advance. The fuel injection amount and ignition timing stipulated in the first operating state map are such that the internal combustion engine operates with the fuel injection amount and ignition timing stipulated in this map when the cam corresponding to the valve 110 is the small cam 21. When this is done, the fuel injection amount and the ignition timing are such that the operating state of the internal combustion engine becomes good. The fuel injection amount and ignition timing specified in the second operation state map are such that the internal combustion engine is operated at the fuel injection amount and ignition timing specified in this map with the cam corresponding to the valve 110 being the large cam 22. In such a case, the fuel injection amount and the ignition timing are such that the operating state of the internal combustion engine becomes good. Note that the fuel injection amount and ignition timing at which the operating state of the internal combustion engine is good include, for example, the fuel injection amount and ignition timing at which fuel consumption is good, the fuel injection amount and ignition timing at which the emission is good, etc. Can be used.

  In the cam switching control, the control unit instructs the drive unit 32 of the displacement mechanism 30 so that the cam corresponding to the valve 110 is switched from the large cam 22 to the small cam 21. Is switched from the second operating state map used so far to the first operating state map. In addition, in the cam switching control, the control unit gives an instruction to the drive unit 32 of the displacement mechanism 30 so that the cam corresponding to the valve 110 is switched from the small cam 21 to the large cam 22. The time map is switched from the first operating state map used so far to the second operating state map. As described above, the control unit executes the operation state change control.

  FIG. 7 is a diagram illustrating an example of a flowchart when the control device 50 according to the present embodiment executes the operation state change control. The control unit of the control device 50 repeatedly executes the flowchart of FIG. 7 every predetermined period. First, the control unit executes cam switching control (step S30).

  Specifically, when the target cam position set in step S11 of FIG. 6 is the position where the small cam 21 corresponds to the valve 110, the control unit moves the displacement mechanism so that the outer cam 20 becomes the target cam position. 30 is controlled. Specifically, the control unit gives an instruction to the drive unit 32 so that the groove engaging member 31 protrudes from the drive unit 32 and engages with the first vertical portion 70 of the groove 27. Further, when the target cam position set in step S11 of FIG. 6 is a position where the large cam 22 corresponds to the valve 110, the control unit controls the displacement mechanism 30 so that the outer cam 20 becomes the target cam position. To do. Specifically, the control unit gives an instruction to the drive unit 32 so that the groove engaging member 31 protrudes from the drive unit 32 and engages with the second vertical portion 72 of the groove 27.

  Next, the control unit determines whether or not it is immediately after performing the control of step S30 (step S31). Specifically, in step S31, the control unit determines whether or not an elapsed time after giving an instruction to the drive unit 32 in step S30 is within a predetermined time (for example, several seconds). In step S31, when it is determined that the elapsed time after giving the instruction to the drive unit 32 in step S30 is within a predetermined time, the control unit determines that it is immediately after performing the control of step S30.

  If it is determined in step S31 that it is immediately after performing the control in step S30 (that is, if it is determined as Yes), the control unit changes the fuel injection amount and the ignition timing (step S32). Specifically, the control unit changes the map of the fuel injection amount and the ignition timing to a map corresponding to the current cam (first operation state map or second operation state map). Next, the control unit ends the execution of the flowchart. When it determines with No by step S31, a control part complete | finishes execution of a flowchart.

  Then, the effect of the variable valve apparatus 5 is demonstrated. First, according to the variable valve operating apparatus 5, the passage area of the oil communication passage is configured to change according to the position of the outer cam 20 in the axial direction with respect to the inner shaft 10. When the position in the axial direction relative to 10 changes, the oil pressure in the shaft passage 12 also changes as a result of the change in the passage area of the oil communication passage. Accordingly, the control device 50 can detect the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12.

  Specifically, according to the variable valve operating apparatus 5, the outer cam 20 includes the small communication path 25 and the large communication path 26, and therefore the oil communication path that connects the shaft path 12 and the outer peripheral surface 24 of the outer cam 20. The area can be changed according to the position of the outer cam 20 in the axial direction relative to the inner shaft 10. Thereby, the oil pressure in the shaft passage 12 can be changed according to the position of the outer cam 20 in the axial direction relative to the inner shaft 10. As a result, the control device 50 can detect the axial position of the outer cam 20 with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12. Based on this mechanism, the control device 50 according to the present embodiment actually detects the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the detection result of the pressure sensor 42.

  Further, according to the variable valve operating apparatus 5, since the outer peripheral surface 24 of the outer cam 20 is pivotally supported by the cam journal 120, it passes through the oil communication path of the outer cam 20 and is supplied to the outer peripheral surface 24 of the outer cam 20. The oil thus used can be used for lubricating the outer cam 20 and the cam journal 120.

  Here, since the urging force of the valve spring 112 increases in accordance with the lift amount of the valve 110, the amount of oil supplied to the outer peripheral surface 24 of the outer cam 20 should increase as the lift amount of the valve 110 increases. The outer cam 20 and the cam journal 120 are preferable in that wear can be effectively suppressed. In other words, when the lift amount of the valve 110 is small, the amount of oil supplied to the outer peripheral surface 24 of the outer cam 20 is smaller than the case where the lift amount of the valve 110 is large. Wear with the cam journal 120 can be suppressed.

  In this regard, according to the variable valve gear 5, the cam profile of the small cam 21 is the cam profile in which the valve 110 is not lifted by the small cam 21, or the lift amount of the valve 110 driven by the small cam 21 is Since the cam profile is smaller than the lift amount of the driven valve 110, when the small cam 21 corresponds to the valve 110, the biasing force received by the outer cam 20 from the valve 110 biased by the valve spring 112 is large. When the large cam 22 corresponds to the valve 110, the outer cam 20 is smaller than the magnitude of the biasing force received from the valve 110. Therefore, the passage area of the small continuous passage 25 is smaller than the passage area of the large continuous passage 26, so that the amount of oil that passes through the small continuous passage 25 and is supplied to the outer peripheral surface 24 of the outer cam 20 passes through the large continuous passage 26. Even when the amount of oil supplied to the outer peripheral surface 24 is smaller, wear of the outer cam 20 and the cam journal 120 can be suppressed.

  Further, according to the variable valve gear 5, the control device 50 determines whether or not the axial position of the outer cam 20 relative to the inner shaft 10 is abnormal based on the oil pressure in the shaft passage 12. An abnormality in the position of the outer cam 20 in the axial direction relative to the inner shaft 10 can also be detected.

  Further, according to the variable valve operating device 5, since the operation state change control is executed, at least one of the fuel injection amount and the ignition timing of the internal combustion engine is changed according to the type of the cam corresponding to the valve 110 after the cam switching. can do. Thereby, the operating state of the internal combustion engine can be appropriately controlled according to the type of cam corresponding to the valve 110.

  As a mechanism for detecting the axial position of the outer cam 20 with respect to the inner shaft 10, for example, a gap sensor is used instead of the mechanism according to the present embodiment to detect the axial position of the outer cam 20 with respect to the inner shaft 10. The following problems may occur when it is considered that the mechanism to be adopted cannot be adopted. Specifically, in order to mount a position detection mechanism using a gap sensor, it is necessary to secure a wide space, but it is difficult to secure such a space in the variable valve operating apparatus. Therefore, in order to apply the position detection mechanism using the gap sensor to the variable valve apparatus, it may be necessary to increase the size of the variable valve apparatus. In addition, when a position detection mechanism using a gap sensor is applied, the manufacturing cost of the variable valve operating apparatus may increase.

  In this regard, according to the variable valve operating apparatus 5 according to the present embodiment, a small-scale design change (setting of the oil communication path, installation of the pressure sensor 42) is performed as compared with the case where the position detection mechanism using the gap sensor is applied. It is possible to detect the position of the outer cam 20 in the axial direction. Therefore, an increase in manufacturing cost can be suppressed. Moreover, the enlargement of the variable valve operating apparatus 5 can also be suppressed. In this respect, the variable valve apparatus 5 is superior to a variable valve apparatus having a position detection mechanism using a gap sensor.

  Next, the variable valve gear 5a according to the second embodiment of the present invention will be described. The variable valve operating apparatus 5a according to the present embodiment is different from the variable valve operating apparatus 5 according to the first embodiment in that a control apparatus 50a is provided instead of the control apparatus 50. The control device 50a differs from the cam position detection abnormality determination control according to the first embodiment in the content of the cam position detection abnormality determination control. Since the other structure of the variable valve operating apparatus 5a is the same as that of the variable valve operating apparatus 5 according to the first embodiment, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  The control device 50a uses a map different from the map according to the first embodiment described in FIG. 5 as the reference pressure map of the shaft passage 12 used in the cam position detection abnormality determination control. FIG. 8 is a diagram for explaining a map of the reference pressure of the shaft passage 12 used in the cam position detection abnormality determination control according to the present embodiment. Specifically, FIG. 8 is a diagram visualizing an example of a reference pressure map of the shaft passage 12 according to the present embodiment. The horizontal axis in FIG. 8 indicates the rotational speed (rpm) of the internal combustion engine, and the vertical axis indicates the oil pressure (Pa) in the shaft passage 12. The curve shown in FIG. 8 is such that the oil pressure in the shaft passage 12 increases as the rotational speed increases. In this embodiment, the oil pressure corresponding to this curve is used as the reference pressure of the shaft passage 12. This map is stored in advance by the storage unit of the control device 50a.

  The control unit of the control device 50a acquires the rotational speed of the internal combustion engine based on the detection result of the crank position sensor 40, and acquires the reference pressure corresponding to the acquired rotational speed from the map of FIG. For example, when the acquired rotation speed is B (rpm), the control unit acquires Po as the reference pressure.

  When the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is larger than the reference pressure Po, the control unit determines that the target cam position is a position corresponding to the valve 110. Detects that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is a position where the small cam 21 corresponds to the valve 110, and the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is normal. Judge that there is.

  On the other hand, when the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is larger than the reference pressure Po, when the target cam position is a position corresponding to the valve 110, Although the detection result of the pressure sensor 42 indicates that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 indicates that the small cam 21 corresponds to the valve 110, the target cam position is the large cam. Since 22 is a position corresponding to the valve 110, the control unit determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal. That is, the control unit detects that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the small cam 21 corresponds to the valve 110, and the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is detected. Judged to be abnormal.

  In addition, when the oil pressure in the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is equal to or lower than the reference pressure Po, the control unit determines that the target cam position is a position where the large cam 22 corresponds to the valve 110. The position of the outer cam 20 in the axial direction relative to the inner shaft 10 detects that the large cam 22 is at a position corresponding to the valve 110, and the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is normal. It is determined that

  On the other hand, when the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is equal to or lower than the reference pressure Po, when the target cam position is a position corresponding to the valve 110, Although the detection result of the pressure sensor 42 indicates that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 indicates that the large cam 22 corresponds to the valve 110, the target cam position is the small cam. Since 21 is a position corresponding to the valve 110, the control unit determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is abnormal. That is, the control unit detects that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is the position where the large cam 22 corresponds to the valve 110, and the position of the outer cam 20 in the axial direction with respect to the inner shaft 10. Is determined to be abnormal.

  As described above, in the cam position detection abnormality determination control, the control device 50a according to the present embodiment first compares the oil pressure of the shaft passage 12 with the reference pressure to thereby determine the axial direction of the outer cam 20 with respect to the inner shaft 10. Then, it is determined whether or not the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is abnormal by determining whether or not the target cam position conforms to the comparison result. ing. In this respect, the cam position detection abnormality determination control according to the present embodiment is mainly different from the cam position detection abnormality determination control according to the first embodiment.

  FIG. 9 is a diagram illustrating an example of a flowchart when the control device 50a according to the present embodiment executes cam position detection abnormality determination control. The control unit of the control device 50a repeatedly executes the flowchart of FIG. 9 every predetermined period. First, the control unit acquires the oil pressure (P) of the shaft passage 12 based on the detection result of the pressure sensor 42 (step S40). Note that the content of step S40 is the same as the content of step S10 of FIG. 6 according to the first embodiment.

  Next, the control unit acquires the rotational speed of the internal combustion engine based on the detection result of the crank position sensor 40, acquires the reference pressure (Po) corresponding to the acquired rotational speed from the map (FIG. 8) of the storage unit, It is determined whether or not the oil pressure (P) of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 is greater than the acquired reference pressure (Po) (step S41).

  When it is determined in step S41 that the oil pressure (P) in the shaft passage 12 is greater than the reference pressure (Po) (that is, when it is determined as Yes), the control unit sets the target cam position to the small cam 21 corresponding to the valve 110. It is determined whether or not the position is set to be set (step S42).

  The contents of step S42 are the same as step S12 according to the first embodiment. Specifically, in step S42, as in step S12 according to the first embodiment, the control unit determines whether the target cam position set in the storage unit is a position where the small cam 21 corresponds to the valve 110. judge. That is, step S42 is a process for confirming whether or not an instruction (setting) is made to change the cam corresponding to the valve 110 to the small cam 21.

  When it is determined in step S42 that the target cam position is a position corresponding to the valve 110 of the small cam 21 (that is, when it is determined as Yes), the control unit performs the axial direction of the outer cam 20 with respect to the inner shaft 10. Is detected that the small cam 21 is at a position corresponding to the valve 110, and the axial position of the outer cam 20 with respect to the inner shaft 10 is determined to be normal (step S43). . Next, the control unit ends the execution of the flowchart.

  When it is determined No in step S42, the control unit detects that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is that the small cam 21 is a position corresponding to the valve 110, and the outer cam 20 It determines with the position of the axial direction with respect to the inner shaft 10 of 20 being abnormal (step S44). Although the detection result of the pressure sensor 42 indicates that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 indicates that the small cam 21 is a position corresponding to the valve 110, the set target cam Since the position of the large cam 22 corresponds to the valve 110, the control unit determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal. Next, the control unit ends the execution of the flowchart.

  When it is determined No in step S41 (in this case, the oil pressure (P) of the shaft passage 12 is equal to or lower than the reference pressure (Po)), the control unit corresponds to the valve 110 with the target cam position corresponding to the large cam 22. It is determined whether or not the position has been set (step S45). Step S45 is also a process of confirming whether or not an instruction (setting) is made to set the cam corresponding to the valve 110 to the large cam 22.

  When it is determined in step S45 that the target cam position is the position corresponding to the valve 110 of the large cam 22 (that is, when it is determined as Yes), the control unit performs the axial direction of the outer cam 20 with respect to the inner shaft 10. It is determined that the position of the large cam 22 is a position corresponding to the valve 110 and that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is normal (step S46). Next, the control unit ends the execution of the flowchart.

  When it determines with No in step S45, while a control part detects that the position of the axial direction of the outer cam 20 with respect to the inner shaft 10 is the position where the large cam 22 corresponds to the valve 110, the outer cam It determines with the position of the axial direction with respect to the inner shaft 10 of 20 being abnormal (step S47). Although the detection result of the pressure sensor 42 indicates that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 indicates that the large cam 22 corresponds to the valve 110, the set target cam Since the small cam 21 is located at a position corresponding to the valve 110, the control unit determines that the axial position of the outer cam 20 relative to the inner shaft 10 is abnormal. Next, the control unit ends the execution of the flowchart.

  In addition, after step S44 is performed in the flowchart of FIG. 9, the process similar to step S17 of FIG. 6 of Example 1 may be performed, and after step S47 of FIG. 9 is performed, FIG. The same process as step S22 of step 6 may be executed.

  That is, in this case, after step S44 of FIG. 9 is executed, the control unit switches the cam corresponding to the valve 110 from the current cam to another cam in the same manner as in step S17 of the first embodiment. The displacement mechanism 30 is controlled so that 20 is displaced in the axial direction with respect to the inner shaft 10. Next, the control unit executes step S41. Further, after step S47 in FIG. 9 is executed, the control unit switches the cam corresponding to the valve 110 from the current cam to another cam in the same manner as in step S22 in the first embodiment. The displacement mechanism 30 is controlled so as to be displaced in the axial direction with respect to the shaft 10. Next, the control unit executes step S41. Thereafter, when step S44 or step S47 is executed again and it is determined that the axial position of the outer cam 20 with respect to the inner shaft 10 is abnormal, some abnormality has occurred in the internal combustion engine or the variable valve gear 5a. Therefore, the control unit executes alarm notification control that notifies the user of the internal combustion engine of an alarm. Next, the control unit forcibly ends the execution of the flowchart.

  Also in the variable valve operating apparatus 5a according to the present embodiment, the axial position of the outer cam 20 with respect to the inner shaft 10 can be detected as in the first embodiment. Specifically, since the outer cam 20 includes the small communication passage 25 and the large communication passage 26, the passage area of the oil communication passage that connects the shaft passage 12 and the outer peripheral surface 24 is set in the axial direction of the outer cam 20 with respect to the inner shaft 10. It can be changed according to the position. Thereby, the oil pressure in the shaft passage 12 can be changed according to the position of the outer cam 20 in the axial direction relative to the inner shaft 10. As a result, the control device 50 a can detect the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12. Also in the variable valve apparatus 5a, the control device 50a determines whether or not the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal, so that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is determined. Abnormalities can be detected.

  The control device 50a according to the present embodiment also executes the operation state change control as in the first embodiment. Specifically, the control device 50a also executes the flowchart of FIG. Thereby, the operating state of the internal combustion engine can be appropriately controlled according to the type of cam corresponding to the valve 110.

  Next, the variable valve gear 5b according to Embodiment 3 of the present invention will be described. The variable valve apparatus 5b according to the present embodiment is different from the variable valve apparatus 5 according to the first embodiment in that a control apparatus 50b is provided instead of the control apparatus 50. The control device 50b performs displacement mechanism abnormality determination control described later when it is determined in the cam position detection abnormality determination control that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal. The control device 50 is different from the control device 50 according to the first embodiment in that the control when the displacement mechanism is abnormal is further executed. Since the other structure of the variable valve operating apparatus 5b is the same as that of the variable valve operating apparatus 5 according to the first embodiment, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  First, displacement mechanism abnormality determination control according to the present embodiment will be described. In the displacement mechanism abnormality determination control, the control unit of the control device 50b determines that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal as a result of the cam position detection abnormality determination control being executed. The displacement mechanism 30 is controlled so that 20 is displaced in the axial direction with respect to the inner shaft 10. After the displacement mechanism 30 is controlled, the axial direction of the outer cam 20 relative to the inner shaft 10 is determined based on the oil pressure in the shaft passage 12. The position is detected, and it is determined whether or not the displacement mechanism 30 has an abnormality based on the detection result of the position.

  If it is determined that the axial position of the outer cam 20 relative to the inner shaft 10 is abnormal, the axial position of the outer cam 20 relative to the inner shaft 10 is not normal even if the displacement mechanism 30 is controlled. It is conceivable that the displacement mechanism 30 has an abnormality. Based on this mechanism, the control device 50b determines whether or not there is an abnormality in the displacement mechanism 30 in the displacement mechanism abnormality determination control.

  FIG. 10 is a diagram illustrating an example of a flowchart when the control device 50b according to the present embodiment executes the displacement mechanism abnormality determination control. The controller of the control device 50b is a diagram according to the present embodiment when it is determined that the axial position of the outer cam 20 with respect to the inner shaft 10 is abnormal in the cam position detection abnormality determination control according to the first embodiment. 10 flowcharts are executed.

  Specifically, when step S16 of the flowchart of FIG. 6 according to the first embodiment is executed, the control unit according to the present embodiment executes the flowchart of FIG. 10 according to the present embodiment instead of executing step S17. To do. Further, when step S21 of FIG. 6 is executed, the control unit according to the present embodiment executes the flowchart of FIG. 10 according to the present embodiment instead of executing step S22. However, the time when the control unit executes the flowchart of FIG. 10 is not limited to this. For example, the control unit may execute the flowchart of FIG. 10 when step S21 is executed after execution of step S17 in the flowchart of FIG. 6 or when step S16 is executed after execution of step S22.

  Referring to FIG. 10, the control unit determines whether or not the displacement mechanism abnormality flag is ON (step S50). The displacement mechanism abnormality flag is turned on in step S55 described later. Therefore, the displacement mechanism abnormality flag is not turned ON at the first execution of the flowchart.

  When it is not determined in step S50 that the displacement mechanism abnormality flag is ON (that is, when it is determined No), the control unit has an abnormal axial position (cam position) of the outer cam 20 with respect to the inner shaft 10. It is determined whether or not (step S51). Specifically, the control unit determines whether step S16 or step S21 of FIG. 6 according to the first embodiment has been executed. Therefore, when Step S16 or Step S21 of FIG. 6 is executed and the flowchart of FIG. 10 is executed first, Step S51 is determined as Yes.

  When it is determined in step S51 that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal (that is, when it is determined Yes), the control unit causes the outer cam 20 to move in the axial direction with respect to the inner shaft 10. The displacement mechanism 30 is controlled so as to be displaced (step S52). Specifically, the control unit gives an instruction to the drive unit 32 of the displacement mechanism 30 so that the cam corresponding to the valve 110 is switched from the current cam to another cam.

  More specifically, when it is determined in step S51 that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal because the small cam 21 is not in a position corresponding to the valve 110, the outer cam 20 An instruction is given to the drive unit 32 of the displacement mechanism 30 such that the position of the large cam 22 in the axial direction relative to the inner shaft 10 is the position corresponding to the valve 110. Further, when it is determined in step S51 that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal because the large cam 22 is not at the position corresponding to the valve 110, the inner shaft of the outer cam 20 is determined. An instruction is given to the drive unit 32 of the displacement mechanism 30 so that the small cam 21 is positioned corresponding to the valve 110 in the axial direction with respect to the position 10.

  Next, the control unit executes cam position detection abnormality determination control (step S53). Specifically, the control unit executes steps S10, S11, and S12 of the cam position detection abnormality determination control according to the first embodiment, and executes step S13 and step S14 when it is determined Yes in step S12. If it is determined Yes in step S14, step S15 is executed. If it is determined No in step S14, step S16 is executed. In addition, when it is determined No in Step S12, the control unit executes Step S18 and Step S19. When it is determined Yes in Step S19, it executes Step S20. When it is determined No in Step S19. Step S21 is executed.

  Next, the control unit determines whether or not the position of the outer cam 20 in the axial direction (cam position) with respect to the inner shaft 10 is determined to be normal as a result of the execution of step S53 (step S54). That is, when step S51 to step S54 are outlined, as a result of the cam position being determined to be abnormal in step S51, the control unit instructs the drive unit 32 to switch the cam in step S52, and as a result, in step S53 again. As a result of determining whether or not the cam position is normal, it is determined that the cam position is normal in step S54.

  When it determines with the position of the axial direction with respect to the inner shaft 10 of the outer cam 20 being normal in step S54, a control part complete | finishes execution of a flowchart. If it is not determined in step S54 that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is normal (that is, if it is determined No), the control unit determines that there is an abnormality in the displacement mechanism, and the displacement The mechanism abnormality flag is turned on (step S55).

  Next, the control unit executes Step S50. As a result, it is determined in step S50 that the displacement mechanism abnormality flag is ON. When it is determined in step S50 that the displacement mechanism abnormality flag is ON, the control unit executes displacement mechanism abnormality control (step S56). The details of the control when the displacement mechanism is abnormal will be described later. Next, the control unit ends the execution of the flowchart.

  Next, displacement mechanism abnormality control will be described. In the control when the displacement mechanism is abnormal, the control unit of the control device 50b performs control to prohibit execution of the cam switching control. That is, the control unit of the control device 50b according to the present embodiment prohibits the execution of the cam switching control when there is an abnormality in the displacement mechanism 30. Note that the execution of the operation switching control is also prohibited by prohibiting the execution of the cam switching control.

  FIG. 11 is a diagram illustrating an example of a flowchart when the control device 50b according to the present embodiment executes the control when the displacement mechanism is abnormal. The control unit of the control device 50b repeatedly executes the flowchart of FIG. 11 every predetermined period. First, the control unit determines whether or not there is an abnormality in the displacement mechanism 30 (step S60). Specifically, the control unit determines whether or not the displacement mechanism abnormality flag is ON in FIG. 10 described above, and when it is determined that the displacement mechanism abnormality flag is ON, the displacement mechanism 30 is determined in step S60. Is determined to be abnormal. That is, turning on the displacement mechanism abnormality flag in the present embodiment corresponds to detecting an abnormality of the displacement mechanism 30. Therefore, when the flowchart of FIG. 11 is executed for the first time, Step S60 is determined as Yes.

  If it is not determined in step S60 that the displacement mechanism 30 is abnormal (that is, if it is determined No), the control unit executes step S30. Since the content of step S30, step S31, and step S32 is the same as that of FIG.7 S30-step S32 which concerns on Example 1, description is abbreviate | omitted. That is, when there is no abnormality in the displacement mechanism 30, the control unit according to the present embodiment executes the cam switching control (step S30) and the operation state change control (step S32) as in the first embodiment. .

  If it is determined in step S60 that the displacement mechanism is abnormal (that is, if it is determined Yes), the control unit ends the execution of the flowchart. That is, in this case, the control unit prohibits the execution of the cam switching control, and as a result, prohibits the execution of the operation state change control.

  The control unit according to the present embodiment performs the cam position detection abnormality determination control according to the first embodiment, and when it is determined that the axial position of the outer cam 20 with respect to the inner shaft 10 is abnormal, Although the flowchart of FIG. 10 according to the present embodiment is executed, the present invention is not limited to this. When it is determined that the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal as a result of executing the cam position detection abnormality determination control according to the second embodiment, the control unit according to the present embodiment The flowchart of FIG. 10 according to the embodiment may be executed. In this case, the control unit executes the cam position detection abnormality determination control (FIG. 9) according to the second embodiment in the cam position detection abnormality determination control according to Step S53 of FIG. Also, in step S51 and step S54, the control unit determines whether the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is abnormal or normal according to the cam position detection abnormality determination control content according to the second embodiment. To do.

  Also in the variable valve apparatus 5b according to the present embodiment, the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 can be detected. Specifically, since the outer cam 20 includes the small communication passage 25 and the large communication passage 26, the passage area of the oil communication passage that connects the shaft passage 12 and the outer peripheral surface 24 is set in the axial direction of the outer cam 20 with respect to the inner shaft 10. It can be changed according to the position. Thereby, the oil pressure in the shaft passage 12 can be changed according to the position of the outer cam 20 in the axial direction relative to the inner shaft 10. As a result, the control device 50 b can detect the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12. Also in the variable valve gear 5b, since the control device 50b executes the cam position detection abnormality determination control according to the first or second embodiment, an abnormality in the axial position of the outer cam 20 with respect to the inner shaft 10 is detected. can do.

  Further, when the control device 50b of the variable valve operating device 5b determines that the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 is abnormal, the outer cam 20 is displaced in the axial direction with respect to the inner shaft 10. The displacement mechanism 30 is controlled (step S52). After the displacement mechanism 30 is controlled, the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is detected based on the oil pressure in the shaft passage 12 (step S53). It is further determined whether or not there is an abnormality in the displacement mechanism 30 based on the detection result (step S54). Thereby, according to the variable valve operating apparatus 5b, the abnormality of the displacement mechanism 30 can be detected.

  Further, according to the variable valve operating device 5b, the control device 50b executes the cam switching control (step S30) and the operating state change control (step S32) when there is no abnormality in the displacement mechanism 30. The operating state of the engine can be appropriately controlled according to the type of cam corresponding to the valve 110.

  Further, according to the variable valve operating device 5b, the control device 50b prohibits the execution of the cam switching control when there is an abnormality in the displacement mechanism 30 (when No is determined in step S60 in FIG. 11). Flow), it is possible to prevent the cam switching control from being executed and the operation state change control from being executed even though the displacement mechanism 30 is abnormal. As a result, the occurrence of a malfunction (for example, a malfunction such as a torque step or worsening of emission) caused by the cam switching control being performed and the operation state change control being performed even though the displacement mechanism 30 is abnormal. Can be suppressed.

  In the present embodiment, the control device 50b may execute the alarm notification control as described in the first embodiment when the displacement mechanism 30 has an abnormality. In this case, it is preferable in that a warning regarding abnormality of the displacement mechanism 30 can be notified to the user of the internal combustion engine.

  In the variable valve gears according to the first embodiment, the second embodiment, and the embodiment, the control device detects the axial position of the outer cam 20 with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12. By comparing the oil pressure in the passage 12 with the oil pressure in the shaft passage 12 serving as a reference for detecting the axial position of the outer cam 20 relative to the inner shaft 10 (for example, the maps in FIGS. 5 and 8). The position of the outer cam 20 in the axial direction relative to the inner shaft 10 is detected, but the present invention is not limited to this. For example, the control device detects an axial stroke amount of the outer cam 20 with respect to the inner shaft 10 based on the oil pressure of the shaft passage 12, and determines an axial position of the outer cam 20 with respect to the inner shaft 10 based on the detection result. It may be detected.

  As an example of this technique, first, the storage unit of the control device stores in advance a reference pressure that serves as a reference for the stroke amount of the outer cam 20 relative to the inner shaft 10 in the axial direction. The control unit of the control device compares the oil pressure of the shaft passage 12 acquired based on the detection result of the pressure sensor 42 with this reference pressure, thereby determining the stroke amount of the outer cam 20 relative to the inner shaft 10 in the axial direction. To detect. Based on the detected stroke amount of the outer cam 20, the control unit determines whether the position of the outer cam 20 in the axial direction relative to the inner shaft 10 is the position where the small cam 21 corresponds to the valve 110, or the large cam 22 It is detected whether the position corresponds to the valve 110. Also with such a method, the variable valve operating apparatus can detect the position of the outer cam 20 in the axial direction with respect to the inner shaft 10 based on the oil pressure in the shaft passage 12.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such 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.

DESCRIPTION OF SYMBOLS 5 Variable valve apparatus 10 Inner shaft 11 Axis line 12 Shaft path 20 Outer cam 21 Small cam 22 Large cam 24 Outer peripheral surface 25 Small communication path 26 Large communication path 27 Groove 30 Displacement mechanism 42 Pressure sensor 50 Control apparatus 110 Valve

Claims (4)

An outer cam having a plurality of cams having different cam profiles as cams corresponding to a valve of an internal combustion engine;
An inner shaft inserted into the outer cam;
A displacement mechanism for displacing the outer cam in the axial direction of the inner shaft with respect to the inner shaft;
A control device for controlling the displacement mechanism,
The inner shaft is formed with a shaft passage that is a passage through which oil passes, and the outer cam is formed with an oil communication passage that communicates the shaft passage with the outer peripheral surface of the outer cam.
The oil communication path is configured such that a passage area of the oil communication path changes according to a position of the outer cam in the axial direction with respect to the inner shaft,
The control device detects a position of the outer cam in the axial direction with respect to the inner shaft based on a pressure of the oil in the shaft passage ;
The outer peripheral surface of the outer cam is pivotally supported by a cam journal,
The plurality of cams include a first cam and a second cam,
The cam profile of the first cam is a cam profile in which the valve is not lifted by the first cam, or a lift amount of the valve driven by the second cam is a lift amount of the valve driven by the first cam. Cam profile smaller than the amount,
The oil communication path communicates the shaft path and the outer peripheral surface of the outer cam when the position of the outer cam in the axial direction with respect to the inner shaft is a position corresponding to the valve. The shaft passage and the outer peripheral surface of the outer cam communicate with each other when the position of the first oil communication passage in the axial direction of the outer cam with respect to the inner shaft is the position corresponding to the second cam. A second oil communication path that
A variable valve operating apparatus in which a passage area of the first oil communication passage is smaller than a passage area of the second oil communication passage . The variable valve according to claim 1 , wherein the control device further determines whether or not the position of the outer cam in the axial direction with respect to the inner shaft is abnormal based on the pressure of the oil in the shaft passage. apparatus. The control device controls the displacement mechanism so that the outer cam is displaced in the axial direction with respect to the inner shaft when the position of the outer cam in the axial direction with respect to the inner shaft is abnormal. After controlling the displacement mechanism, the axial position of the outer cam relative to the inner shaft is detected based on the oil pressure in the shaft passage, and the displacement mechanism is abnormal based on the position detection result. The variable valve operating apparatus according to claim 2, further determining whether or not there is. The control device responds to the valve of the internal combustion engine by controlling the displacement mechanism so that the outer cam is displaced in the axial direction with respect to the inner shaft when there is no abnormality in the displacement mechanism. The cam switching control for switching the cam to be performed among the plurality of cams of the outer cam is performed, and after the cam switching control is performed, the cam of the internal combustion engine after the cam switching control is performed. Performing an operating state change control for changing at least one of the fuel injection amount and the ignition timing of the internal combustion engine according to the type of the cam;
The variable valve operating apparatus according to claim 3, wherein the control device prohibits execution of the cam switching control when there is an abnormality in the displacement mechanism.

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