JP4195351B2 - Internal combustion engine - Google Patents

Description

  In particular, the present invention includes a first variable mechanism that controls the lift operation angle center position of an engine valve that is an intake valve or an exhaust valve, and a second variable mechanism and engine valve that change an engine compression ratio by changing piston stroke characteristics. The present invention relates to an internal combustion engine including a third variable mechanism that changes the lift amount of the engine.

  As is well known, for example, the valve timing characteristics of the intake valve, that is, the variable valve timing mechanism that makes the lift operation center position variable to the advance side or the retard side, and the valve lift amount and the operation angle (lift operation angle) continuously An internal combustion engine that includes a variable lift mechanism that changes and a variable compression ratio mechanism that continuously changes piston stroke characteristics to make the engine compression ratio variable is described in Patent Document 1 below.

  According to this internal combustion engine, by using both the variable valve timing mechanism and the variable lift mechanism, the opening timing and closing timing of the intake valve can be adjusted independently of each other, and the lift operating angle and center of the intake valve can be adjusted. Since the phase can be continuously changed, the valve lift characteristic of the intake valve can be controlled to a high degree, so that the intake air intake amount can be accurately adjusted according to the engine operating state.

In addition, by changing the piston stroke characteristics by the variable compression ratio mechanism, the engine compression ratio can be continuously changed according to the engine operating state, so that the startability is improved by high compression at the time of engine start, The engine performance can be greatly improved such that knocking due to low compression at the time of engine high load can be suppressed.
JP 2003-35111 A

  However, in the conventional internal combustion engine, the engine performance can be greatly improved by the combination of the mechanisms. However, when the mechanism is locked due to a failure of each mechanism, the control lift amount of the intake valve or Depending on the stroke control position of the piston, the intake valve and the piston may interfere with each other.

  For example, if the variable valve lift mechanism fails and locks during the control of the intake valve to the maximum advance angle during the control in which the piston stroke position maximizes the compression ratio, the engine is operating. If the piston is at the top dead center position and the intake valve is open, the piston and the intake valve may interfere with each other.

  The present invention has been devised in view of the actual situation of the conventional internal combustion engine, and the invention according to claim 1 is, in particular, when any one of the variable mechanisms is determined to be abnormal by the abnormality detection means. The central phase of the lift operating angle of the engine valve is controlled by the first variable mechanism in a direction away from the top dead center position of the piston, or the second variable mechanism controls the piston stroke characteristic to reduce the engine compression ratio. Further, a fail-safe means for outputting a control signal to be controlled to at least one of the normal variable mechanisms is provided.

  According to this invention, even if one of the variable mechanisms fails, the normal variable mechanism is controlled to the safe side by the fail-safe means, so that interference between the piston and the engine valve is avoided at the top dead center position of the piston. Can be made.

  According to a second aspect of the present invention, when the abnormality detecting means determines that any one of at least three variable mechanisms is abnormal, the first variable mechanism determines the center phase of the lift operating angle of the engine valve as the piston. Or the second variable mechanism controls the piston stroke characteristics so as to reduce the engine compression ratio, or the third variable mechanism controls the lift amount of the engine valve. The present invention is characterized in that fail-safe means for outputting a control signal for controlling to be reduced to any one of the normal variable mechanisms is provided.

  According to the present invention, as in the first aspect of the invention, even if one of the variable mechanisms fails, the normal variable mechanism is controlled to the safe side by the fail-safe means, so that interference between the piston and the engine valve is avoided. Can be made.

  According to a third aspect of the present invention, in the state where the engine compression ratio is controlled to the minimum by the second variable mechanism, the center phase of the lift operating angle of the engine valve is either advanced or retarded by the first variable mechanism. The engine valve and the piston are configured not to interfere with each other even in the control position, and the engine compression ratio is determined by the second variable mechanism when the abnormality detecting means determines that the first variable mechanism is abnormal. Is controlled to be minimized.

  According to the present invention, when the failure of the first variable mechanism occurs, the second variable mechanism controls the stroke position of the piston to the minimum compression ratio, so that the center phase (advance angle, delay angle) of the lift operating angle of the engine valve is controlled. Whatever position the side) is, it is possible to reliably avoid interference between the piston and the engine valve at the piston top dead center position.

  FIG. 1 shows an embodiment of an internal combustion engine according to the present invention. Intake valves 2 and 2, which are two engine valves per cylinder, are slidably provided on a cylinder head 1 via a valve guide (not shown). The variable valve timing mechanism 4, which is a first variable mechanism that includes the exhaust valves 3 and 3, and makes the center phase of the lift operating angle of the intake valves 2 and 2 variable to the advance side or the retard side, A variable compression ratio mechanism 5 that is a second variable mechanism that makes the engine compression ratio variable by changing the stroke characteristics, and a variable lift that is a third variable mechanism that continuously controls the lift amount and valve operating angle of the engine valve. A mechanism 6 and an electronic controller 8 (ECU) for controlling each of the mechanisms 4 to 6 according to the engine operating state are provided.

  As shown in FIG. 3, the variable valve timing mechanism 4 is provided on the distal end side of a hollow drive shaft 9 that is rotatably supported by a bearing on the cylinder head 1. A timing sprocket 10 to which a rotational force is transmitted from the crankshaft 11, a sleeve 12 fixed from the axial direction to the front end portion of the drive shaft 9 by a bolt, and interposed between the timing sprocket 10 and the sleeve 12, The peripheral gear includes a cylindrical gear 13 having helical teeth formed on its peripheral surface, and a hydraulic circuit 14 that is a drive mechanism that drives the cylindrical gear 13 in the front-rear axial direction of the drive shaft 9.

  In the timing sprocket 10, a sprocket portion 10b around which a chain is wound is fixed to a rear end portion of the cylindrical main body 10a by a bolt, and a front end opening of the cylindrical main body is closed by a front cover 10c. Further, on the inner peripheral surface of the cylindrical main body 10a, an inner tooth of a helical shape that engages with the external teeth of the cylindrical gear 13 is formed.

  The sleeve 12 is formed with a fitting groove for fitting the front end of the drive shaft 9 on the rear end side, and the timing sprocket 10 is attached to the front holding groove at the front end via a front cover 10c. An energizing coil spring 15 is mounted. Further, on the outer peripheral surface of the sleeve 12, a helical outer tooth that engages with the internal teeth of the cylindrical gear 13 is formed.

  The cylindrical gear 13 is adapted to move in the front-rear axis direction while sliding between the teeth by the hydraulic pressure relatively supplied to the first and second hydraulic chambers 16 and 17 formed at the front and rear. The intake valves 2 and 2 are controlled to the most retarded angle position at the maximum forward movement position hitting the front cover 10c, while being controlled to the most advanced angle position at the maximum rearward movement position. Further, when the hydraulic pressure of the first hydraulic chamber 16 is not supplied by the return spring 18 mounted in the second hydraulic chamber 17, it is biased to the maximum forward movement position.

  The hydraulic circuit 14 has a main gallery connected to a downstream side of an oil pump 19 that communicates with an oil pan (not shown), and branches to the first and second hydraulic chambers 16 and 17 at a downstream side of the main gallery. The first and second hydraulic passages 20 and 21 connected to each other, a solenoid-type flow path switching valve 22 provided at the branch position, and a drain path 23 connected to the flow path switching valve 22 are configured. Yes. The flow path switching valve 22 is switched and driven by a control signal from the electronic controller 8.

  As shown in FIGS. 1 and 2, the variable compression ratio mechanism 5 has both ends between a crank arm 11 a coupled to the crankshaft 11 and a lower end portion of a connecting rod 24 whose upper end portion is linked to the piston 7. The first link 25 having a substantially square shape, the part of which is rotatably connected via pins 25a and 25b, and one end of the first link 25 are rotatably connected to the lower end of the connecting rod 24 via a pin 26a. The second link 26 includes an electric actuator 28 that is a DC electric motor linked to the other end of the second link 26 via an eccentric cam 27.

  The eccentric cam 27 is slidably held in a sliding hole 26 a formed at the center of the other end of the second link 26.

  The electric actuator 28 is controlled to rotate forward and backward by a control current from the electronic controller 8, and rotates the eccentric cam 27 forward and backward via the reduction gear 29, so that the second link 26 moves in the axial direction. The first link 25 is raised or inclined with respect to the crank arm 24 a to change the vertical stroke position of the piston 7 via the connecting rod 24.

  As shown in FIGS. 3 and 4, the variable lift mechanism 6 is supported by an eccentric drive cam 30 fixed to the drive shaft 9 and swingably supported by the drive shaft 9. Oscillating cams 32, 32 that slide openly contact the flat upper surfaces of the valve lifters 31, 31 arranged at the upper end of each of the valve lifters to open the intake valves 2, 2, and the eccentric drive cam 30 and oscillating cam 32. A transmission mechanism linked with the transmission mechanism for transmitting the rotational force of the eccentric drive cam 30 as the swinging force of the swing cam, and a control mechanism for variably controlling the operating position of the transmission mechanism.

  The eccentric drive cam 30 has a substantially ring shape, a drive shaft insertion hole is formed through the inner shaft direction, and the shaft center X is offset from the shaft center Y of the drive shaft 9 by a predetermined amount in the radial direction. Yes.

  The rocking cam 32 is formed with a support hole that is rotatably inserted in the annular base end portion on one end side so as to be rotatably supported, and the cam nose portion 32a on the other end portion. A pin hole is formed therethrough, and a cam surface 32b that is slidably in contact with the upper surface of the valve lifter 31 is formed on the lower surface.

  The transmission mechanism includes a rocker arm 33 disposed above the drive shaft 9, a link arm 34 that links one end of the rocker arm 33 and the eccentric drive cam 30, the other end of the rocker arm 33, and a swing cam 32. And a link rod 35 that links the two.

  Each of the rocker arms 33 is bent in a substantially crank shape when viewed from above, and a cylindrical base portion provided at the center is rotatably supported by a control cam 40 described later. Further, as shown in FIG. 4, the one end portion is formed with a pin hole through which a pin 36 connected to the link arm 34 so as to be relatively rotatable is penetrated. A pin hole is formed through which a pin 37 connected to one end of the link rod 35 so as to be relatively rotatable is inserted.

  The link arm 34 includes an annular base portion having a relatively large diameter and a protruding end projecting at a predetermined position on the outer peripheral surface of the base portion. A fitting hole that is rotatably fitted to the surface is formed, and a pin hole through which the pin 36 is rotatably inserted is formed in the protruding end.

  Further, the link rod 35 is bent into a substantially rectangular shape having a predetermined length, and pin insertion holes are formed at both ends. The other end of the rocker arm 33 is formed in each pin insertion hole. The end portions of the pins 37 and 38 respectively inserted through the pin holes formed in the cam holes and the pin holes formed in the cam nose portion 32a of the swing cam 32 are rotatably inserted.

  The control mechanism controls the control shaft 39 disposed in the longitudinal direction of the engine, a control cam 40 fixed to the outer periphery of the control shaft 39 and serving as a rocking fulcrum of the rocker arm 33, and the rotational position of the control shaft 39. The electric motor 41 is configured.

  The control shaft 39 is provided in parallel with the drive shaft 9 and is rotatably supported by the bearing as described above, while the control cams 40 each have a cylindrical shape, and the position of the axis P1 is controlled. It is deviated from the axis P2 of the shaft 39 by α.

  The electric motor 41 rotates to the control shaft 39 through meshing of a first spur gear 42 provided at the front end portion of the rotary shaft and a second spur gear 43 provided at the rear end portion of the control shaft 39. Power is transmitted, and the system is driven by a control signal from the electronic controller 8 that detects the operating state of the engine.

  The electronic controller 8 detects the current engine operating state by calculation based on various parameters such as an engine speed signal from a crank angle sensor, an intake flow signal (engine load) from an air flow meter, and an engine oil temperature sensor. Thus, the fuel injection amount and ignition timing are controlled. Further, the engine operating state, the current rotational position of the control shaft 39, the detection signal from the position detection sensor (not shown) for detecting the relative rotational position of the drive shaft 9 and the timing sprocket 40, and the inside of the cylinder 1a of the piston 7 are detected. A control signal (control current) is output to each of the flow path switching valve 22, the electric actuator 28, and the electric motor 41 based on a detection signal from a stroke position detection sensor that detects the current stroke position at.

  That is, on the variable valve timing mechanism 4 side, for example, in a predetermined low rotation range from the start of the engine, the flow path switching valve 22 switches the flow path by the control current from the electronic controller 8, and only the second hydraulic chamber 17. The hydraulic pressure is supplied and no hydraulic pressure is supplied to the first hydraulic chamber 16. Therefore, the cylindrical gear 13 is held at the maximum front position by the spring force of the return spring 18, and the drive shaft 9 is held at the maximum retarded rotational position.

  Thereafter, when the engine rotation is shifted to the high rotation range, the flow path switching valve 22 is driven to connect the first hydraulic passage 20 and the main gallery, and the second hydraulic passage 21 and the drain passage 23 are connected. As a result, the cylindrical gear 13 moves from the foremost position to the rearmost position. Therefore, the opening / closing timing of the intake valves 2 and 2 is changed from the most retarded state shown by the broken line to the most advanced line shown in FIG. Continuously variable control until the lead angle.

  As a result, the valve overlap between the intake valve 2 and the exhaust valve 3 is increased, and a sufficient intake air amount is introduced to improve the output torque.

  Further, when the variable compression ratio mechanism 5 is, for example, at the time of engine start and idling, the electric actuator 28 is rotated in one direction by the control current output from the electronic controller 8 and the eccentric cam 27 is rotated in the same direction. As shown in FIG. 2, the second link 26 moves in the right axis direction to raise the first link 25 substantially vertically. As a result, the piston 7 strokes the cylinder 1a upward by a predetermined amount via the connecting rod 24, and controls the combustion chamber to a high compression ratio. As a result, good startability and improved fuel efficiency can be achieved.

  On the other hand, when the engine shifts to the high engine speed and high load range, when the electric actuator 28 reverses and the eccentric cam 27 rotates in the same direction, the second link 26 moves in the left axis direction as shown in FIG. The link 25 is rotated in the direction of tilting. As a result, the piston 7 travels downward within the cylinder 1a by a predetermined amount via the connecting rod 24 to control the combustion chamber to a low compression ratio, thereby preventing so-called knocking.

  The vertical stroke characteristic of the piston 7 for obtaining such low compression ratio control and high compression ratio control is a waveform characteristic as indicated by Q in FIG. 5, and is the characteristic of Q1 at the uppermost position and Q2 at the lowermost position. Indicates.

  Further, in the variable lift mechanism 6, for example, at the time of cranking and idling at the initial stage of engine start, the control shaft 39 is controlled to rotate in one direction by the electronic controller 8 via the electric motor 41, and the control cam 40. The shaft center P1 is held at the upper left rotation position from the shaft center P2 of the control shaft 39, and the thick wall portion rotates away from the drive shaft 9 upward. As a result, the entire rocker arm 33 moves upward with respect to the drive shaft 9, so that each swing cam 32 is forcibly pulled up via the link rod 35 and rotated counterclockwise. Therefore, when the drive cam 30 rotates and pushes up the one end portion 23a of the rocker arm 33 via the link arm 34, the lift amount is transmitted to the swing cam 32 and the valve lifter 16 via the link rod 35. The lift amount becomes smaller as shown by the solid line and the broken line in FIG. 5 (L1). For this reason, gas flow is strengthened, combustion is improved, fuel consumption can be improved, and engine rotation can be stabilized.

  On the other hand, in the high rotation and high load region, the electric motor 41 rotates the control cam 40 via the control shaft 39 by the control signal from the electronic controller 8 so that the thick portion is positioned downward. For this reason, the rocking cam 32 is pressed downward by the rocker arm 33 via the link arm 25 to rotate the entire rocking cam 32 by a predetermined amount. Therefore, when the drive cam 30 rotates and pushes up one end of the rocker arm 33 via the link arm 34, the lift amount is transmitted to the swing cam 32 and the valve lifter 16 via the link rod 35. The amount is the largest as shown in FIG. 5 (L2). As a result, the charging efficiency of the intake air intake amount is increased, and the output torque can be improved.

  The electronic controller 8 includes an abnormality detection circuit which is an abnormality detection means for detecting an operation abnormality of each of the variable valve timing mechanism 4, the variable compression ratio mechanism 5, and the variable lift mechanism 6, and at least the abnormality detection circuit uses the abnormality detection circuit. A fail-safe circuit that is a fail-safe means for controlling the operation of the normal mechanism to prevent interference between the intake valves 2 and 2 and the piston 7 when any of the variable mechanisms is determined to be abnormal; Yes.

  More specifically, the abnormality detection circuit is in a raised position (high compression) in accordance with an input signal from the stroke position detection sensor of the piston 7 in spite of, for example, during high engine speed and high load. If it is detected that the variable compression ratio mechanism 5 is in failure, it is determined that the variable compression ratio mechanism 5 has failed, and the signal is output to the fail-safe circuit.

  This fail-safe circuit first supplies a hydraulic pressure to the first hydraulic chamber 16 by outputting a control signal to, for example, the flow path switching valve 22 to the variable valve timing mechanism 4 based on an output signal from the abnormality detection circuit. Instead, the cylindrical gear 13 is moved to the forefront position by the return spring 18 to control the lift operation center position to the most retarded angle side (broken line in FIG. 5). That is, as shown in FIG. 5, the piston 7 is controlled to a position that is avoided from the top dead center position at the highest rise position Q <b> 1.

  Further, this fail-safe circuit simultaneously outputs a control signal to the electric motor 41 of the variable lift mechanism 6 so that the lift amount of the intake valve 2 becomes the minimum stroke (L1) shown in FIG. 5 as described above. Control.

  For this reason, it is possible to reliably avoid interference between the crown surface of the piston 7 and the umbrella portion of the intake valve 2 at the top dead center position (TDC).

  In addition, when the variable valve timing mechanism 4 is locked due to a failure in the most advanced angle control state, for example, an information signal is output from the abnormality detection circuit that has detected this state to the fail safe circuit. .

  Then, this fail-safe circuit first outputs a control signal to the electric actuator 28 of the variable compression ratio mechanism 5 to control the stroke characteristic of the piston 7 so as to reach the maximum downward position (Q2) as described above.

  At the same time, a control signal is output to the electric motor 41 of the variable lift mechanism 6 to control the lift amount of the intake valves 2 and 2 to the aforementioned small lift amount (L1).

  Thus, even if the lift operation center position of the intake valves 2 and 2 is locked to the advance side, the interference between the crown surface of the piston 7 and the umbrella portion of the intake valves 2 and 2 at the top dead center position is surely prevented. can do.

  Further, when the variable lift mechanism 6 is locked due to a failure in, for example, the maximum lift control state of the intake valve 2, an information signal is sent from the abnormality detection circuit that has detected this state to the fail safe circuit by the position sensor. Is output.

  Then, this fail-safe circuit first outputs a control signal to the electric actuator 28 of the variable compression ratio mechanism 5 to control the stroke characteristic of the piston 7 so as to be at the lowest position (Q2) as described above.

  At the same time, a control signal is output to the flow path switching valve 22 of the variable valve timing mechanism 4 so that the hydraulic pressure is not supplied to the first hydraulic chamber 16, and the cylindrical gear 13 is moved to the foremost position by the return spring 18 and lifted. The operation center position is controlled to the most retarded angle side (broken line in FIG. 5). That is, as shown in FIG. 5, the piston 7 is controlled to a position avoiding from the most elevated position Q1.

  Therefore, also in this case, it is possible to reliably avoid interference between the crown surface of the piston 7 and the umbrella portion of the intake valve 2 at the top dead center position.

  As another embodiment, when the stroke position of the piston 7 of the variable compression ratio mechanism 5 is controlled to the minimum engine compression ratio (FIG. 5Q2), the variable valve timing mechanism 4 causes the intake valves 2 and 2 to Regardless of whether the center phase of the lift operating angle is at the maximum advance angle or the maximum retard angle control position, the intake valves 2 and 2 and the piston 7 are configured not to interfere with each other, and are variable by the abnormality detection circuit. When it is determined that the valve timing mechanism 4 is abnormal, the stroke position of the piston 7 of the variable compression ratio mechanism 4 is controlled to the lowest position by a fail safe circuit so that the engine compression ratio is minimized. .

  Thus, when the variable valve timing mechanism 4 fails, the variable compression ratio mechanism 5 controls the stroke position of the piston 7 so as to be the minimum compression ratio. It is possible to reliably avoid interference between the piston 7 and the intake valves 2 and 2 at the top dead center position regardless of the position of the angle or retard side) due to the failure.

  As another embodiment, when a failure occurs in any one of the mechanisms 4 to 6 and the abnormality is detected by the abnormality detection circuit, the electronic controller 8 is connected to another normal mechanism 4 to 6. Control by is stopped. At the same time, the normal mechanisms 4 to 6 are mechanically controlled so as to be positioned to avoid interference between the piston 7 and the intake valves 2 and 2.

  That is, for example, when the variable valve timing mechanism 4 fails, the electronic controller 8 stops the control of the variable compression ratio mechanism 5 and the variable lift mechanism 6. At the same time, on the variable compression ratio mechanism 5 side, for example, the eccentric cam 27 is forcibly rotated using a torsion spring or the like to move the first link 26 in the left axial direction as shown in FIG. Is controlled to the lowest position (Q2). At the same time, on the variable lift mechanism 6 side, for example, the control shaft 39 is forcibly rotated in one direction using a torsion spring or the like to control to the minimum lift position (L1) of the intake valves 2 and 2. For this reason, even if the variable valve timing mechanism 4 fails, the interference between the piston 7 and the intake valves 2 and 2 can be prevented automatically and reliably. The same applies when another mechanism fails.

  If any one of the mechanisms 4 to 6 fails, an electronic controller 8 energizes a warning light or the like provided on the instrument panel in the vehicle according to an output signal from an abnormality detection circuit that detects the failure. It is possible to make the driver recognize the failure by turning on the light.

  Furthermore, when at least one mechanism is detected as abnormal by the abnormality detection circuit, the electronic controller 8 can control a normal mechanism to a control position where the engine can be restarted when the engine is stopped.

  According to the present invention, for example, when the variable valve timing mechanism 4 fails, the stroke position of the piston 7 is controlled to the highest position by the other normal variable compression ratio mechanism 5 when the engine is stopped, and the variable lift mechanism. If the minimum lift is controlled by 6, the engine restartability is not affected.

  In each of the above embodiments, when one variable mechanism fails, the other two normal variable mechanisms are controlled by the fail-safe circuit. However, the interference between the piston 7 and the intake valves 2 and 2 is prevented. If it can be avoided, it is possible to control only one normal variable mechanism.

The technical ideas other than the inventions described in the respective claims ascertained from the embodiments will be described below.
(1) When an abnormality is detected in at least one of the variable mechanisms by the abnormality detecting means, the control by the other normal variable mechanism is stopped, and the normal mechanisms are interfered with the piston and the engine valve. The internal combustion engine according to any one of claims 1 to 3, wherein the internal combustion engine is mechanically controlled so as to be in a position to avoid the engine.

According to the present invention, the control by the normal variable mechanism is stopped, and at the same time, each variable mechanism is controlled so as to mechanically avoid the interference between the piston and the engine valve. However, interference between the piston and the engine valve can be prevented automatically and reliably.
(2) The warning means which issues a warning to the driver when at least one of the variable mechanisms is abnormally detected by the abnormality detecting means is provided. Internal combustion engine.

According to the present invention, it becomes possible to notify the driver of the failure state of any of the variable mechanisms.
(3) When at least one variable mechanism is abnormally detected by the abnormality detecting means, the normal variable mechanism is controlled to be at a control position where the engine can be restarted when the engine is stopped. The internal combustion engine according to any one of 1 to (2).

  According to the present invention, for example, when the first variable mechanism fails, other normal second and third variable mechanisms control the piston stroke position and the engine valve lift to a position where the engine can be restarted. Therefore, the engine restartability is not affected by the failed first variable mechanism.

  The present invention is not limited to the configuration of the above embodiment, and the mechanisms 4 to 6 can be provided on the exhaust valve 3 side, or can be provided on both.

1 is a schematic view of an embodiment of an internal combustion engine of the present invention. It is the schematic which shows the effect | action of the variable compression ratio mechanism of the internal combustion engine. It is sectional drawing of the variable valve timing mechanism with which this embodiment is provided, and a side view of a variable lift mechanism. It is an AA line sectional view of Drawing 3 showing a variable lift mechanism. It is an operation characteristic figure of each mechanism.

Explanation of symbols

2 ... Intake valve (engine valve)
4. Variable valve lifter mechanism (first variable mechanism)
5. Variable compression ratio mechanism (second variable mechanism)
6 ... Variable lift mechanism (third variable mechanism)
DESCRIPTION OF SYMBOLS 7 ... Piston 8 ... Electronic controller 9 ... Drive shaft 22 ... Flow path switching valve 28 ... Electric actuator 41 ... Electric motor

Claims (3)

A first variable mechanism that makes the center phase of the lift operating angle of the engine valve variable to the advance side or the retard side according to the engine operating state;
A second variable mechanism that changes a stroke characteristic of the piston in accordance with an engine operating state to make the engine compression ratio variable;
An abnormality detecting means for detecting an abnormal operation of each of the first variable mechanism and the second variable mechanism;
In an internal combustion engine with
If the least even one variable mechanism is determined as abnormal by the abnormality detecting means, the center phase of the lift operating angle of the engine valve by the first variable mechanism, to control the direction away from the top dead center position of the piston or, alternatively normal control signal a second variable mechanism is controlled so that the engine compression ratio by controlling the piston stroke characteristic is reduced, Rutotomoni provided a fail-safe means for outputting the normal variable mechanism, when the engine is stopped An internal combustion engine characterized in that the variable mechanism is controlled to be at a control position where the engine can be restarted . A first variable mechanism that makes the center phase of the lift operating angle of the engine valve variable to the advance side or the retard side according to the engine operating state;
A second variable mechanism that changes a stroke characteristic of the piston in accordance with an engine operating state to make the engine compression ratio variable;
A third variable mechanism for controlling the lift amount of the engine valve according to the engine operating state;
An abnormality detecting means for detecting an operation abnormality of each variable mechanism;
In an internal combustion engine with
If any of the abnormality detecting means by Ri before Symbol each variable mechanism is determined to be abnormal, the direction to distance the center phase of the lift operating angle of the engine valve by the first variable mechanism, a top dead center position of the piston Control signal for controlling the piston stroke characteristics to reduce the engine compression ratio, or for the third variable mechanism to reduce the lift amount of the engine valve. and characterized by being controlled so that at least the one of Rutotomoni provided a fail-safe means for outputting the normal variable mechanism, a normal variable mechanism when the engine stops the engine restart possible control positions internal combustion organ. In a state where the engine compression ratio is controlled to the minimum by the second variable mechanism, the engine valve is controlled by the first variable mechanism regardless of whether the center phase of the lift operating angle of the engine valve is at the advanced or retarded control position. And so that the piston does not interfere,
When the abnormality detecting means detects that the first variable mechanism and / or the second variable mechanism is abnormal, the second variable mechanism controls the engine compression ratio to be minimized. Item 3. The internal combustion engine according to Item 1 or 2.

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