JP2014181666A - Variable compression ratio internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress unfavorable noise and vibration while maintaining small input torque and high responsiveness of a reverse input cutoff clutch.SOLUTION: An internal combustion engine includes a variable compression ratio mechanism that can change a mechanical compression ratio by relatively displacing a cylinder block and a crankcase. The variable compression ratio mechanism includes an operation element, an input actuator, and a reverse input cutoff clutch. By moving the operation element, the mechanical compression ratio is changed. A relative displacement suppressor 90 capable of suppressing relative displacement between the cylinder block 2 and the crankcase 1 is installed between the cylinder block and the crankcase. Actuation and stop of the relative displacement suppressor 90 are selectively switched.

Description

  The present invention relates to a variable compression ratio internal combustion engine.

  The variable compression ratio mechanism includes a variable compression ratio mechanism that can change the mechanical compression ratio by relatively moving the cylinder block and the crankcase, and the variable compression ratio mechanism is an input actuator that generates an input torque for moving the operation element. And a reverse input cutoff clutch disposed between the operator and the output shaft of the input actuator for transmitting input torque from the input actuator to the operator and blocking reverse input torque from the operator to the input actuator, There is known an internal combustion engine in which the mechanical compression ratio is changed by moving the operating element.

  In addition, the fixing member, the input member connected to the input actuator, the output member connected to the operation element, and the wedge member that can move between the lock position and the non-lock position between the output member and the fixing member. The output member is prevented from moving in the direction of reverse input torque when the wedge member is in the locked position, and the output member is moved in the direction of reverse input torque when the wedge member is in the unlocked position. When the input member is moved in the direction of the reverse input torque in order to change the mechanical compression ratio, the wedge member is moved from the locked position to the unlocked position, and the input member is further operated by the reverse input torque. A reverse input cutoff clutch is also known in which the input member engages with the output member when moved in the direction and the output member is moved together with the operation element (see Patent Document 1).

  However, if a relatively large reverse input torque acts on the output member when the wedge member is in the unlocked position and the output member is moved in the direction of the reverse input torque, the wedge member may be positioned again in the locked position. There is. Further, there is a possibility that the wedge member is moved again to the unlocked position. As a result, the wedge member may reciprocate between the locked position and the unlocked position. In this case, when the wedge member violently collides with the fixing member, the output member, or the input member when the wedge member is moved to the unlocked position and the locked position, undesirable noise and vibration are generated. Therefore, in Patent Document 1 described above, a compression spring is disposed between the input member and the output member, and relative movement between the input member and the output member is suppressed.

JP 2004-019726 A

  However, in Patent Document 1, relative movement between the input member and the output member is always suppressed. For this reason, in order to move the output member to change the mechanical compression ratio, a large input torque may be required. Further, the response of the reverse input cutoff clutch, that is, the response of the movement of the output member to the input of the input torque may be deteriorated.

  According to the present invention, the variable compression ratio mechanism includes a variable compression ratio mechanism that can change the mechanical compression ratio by relatively moving the cylinder block and the crankcase, and the variable compression ratio mechanism includes an operation element and an input for moving the operation element. An input actuator that generates torque, and an input actuator that transmits input torque from the input actuator to the operating element and is disposed between the operating element and the output shaft of the input actuator to block reverse input torque from the operating element to the input actuator. A reverse input cut-off clutch, and the mechanical compression ratio is changed by moving the operation element. The reverse input cut-off clutch is connected to the fixed member, the input member connected to the input actuator, and the operation element. An output member, and a wedge member movable between a locked position and an unlocked position between the output member and the fixing member, wherein the wedge member is locked. The output member is prevented from moving in the direction of reverse input torque when in the position, and the output member is allowed to move in the direction of reverse input torque when the wedge member is in the unlocked position. When the input member is moved in the direction of the reverse input torque to change the input member, the wedge member is moved from the locked position to the unlocked position, and when the input member is further moved in the direction of the reverse input torque, the input member is moved. A variable compression ratio internal combustion engine that engages with an output member and is moved together with an operating element, wherein relative movement between the cylinder block and the crankcase is performed between the cylinder block and the crankcase. Provided is a variable compression ratio internal combustion engine provided with a suppressable relative movement suppressor and selectively switching between operation and stop of the relative movement suppressor.

  Undesirable noise and vibration can be suppressed while maintaining the input torque small and maintaining the high response of the reverse input cutoff clutch.

1 is an overall view of a spark ignition internal combustion engine. It is a disassembled perspective view of a variable compression ratio mechanism. 1 is a schematic side sectional view of an internal combustion engine. It is the elements on larger scale of a variable compression ratio mechanism. It is a fragmentary sectional view of a reverse input interception clutch. It is the fragmentary sectional view seen along line XI-XI of FIG. It is a figure explaining operation | movement of a reverse input interruption | blocking clutch. It is a figure explaining operation | movement of a reverse input interruption | blocking clutch. It is a partial expanded sectional view of an internal combustion engine. It is a figure explaining the relock of a wedge member. It is a diagram which shows the low load area | region LLA, the medium load area | region MLA, and the high load area | region HLA. 3 is a diagram showing a region X. FIG. It is a figure explaining a link angle. It is a flowchart for performing relative movement suppression control.

  FIG. 1 shows a case where the present invention is applied to a spark ignition type internal combustion engine. The present invention can also be applied to a compression ignition type internal combustion engine.

  Referring to FIG. 1, 1 is a crankcase, 2 is a cylinder block, 3 is a cylinder head, 4 is a piston, 5 is a combustion chamber, 6 is a spark plug disposed at the center of the top surface of the combustion chamber 5, and 7 is intake air. 8 is an intake port, 9 is an exhaust valve, and 10 is an exhaust port. The intake port 8 is connected to a surge tank 12 via an intake branch pipe 11, and a fuel injection valve 13 for injecting fuel into the corresponding intake port 8 is arranged in each intake branch pipe 11. The fuel injection valve 13 may be arranged in each combustion chamber 5 instead of being attached to each intake branch pipe 11.

  The surge tank 12 is connected to an air cleaner 15 via an intake duct 14, and a throttle valve 17 driven by an actuator 16 and an intake air amount detector 18 using, for example, heat rays are arranged in the intake duct 14. On the other hand, the exhaust port 10 is connected to a catalytic converter 20 containing, for example, a three-way catalyst via an exhaust manifold 19, and an air-fuel ratio sensor 21 is disposed in the exhaust manifold 19.

  On the other hand, in the embodiment shown in FIG. 1, the mechanical compression ratio of the internal combustion engine can be changed by changing the relative position of the crankcase 1 and the cylinder block 2 in the cylinder axial direction at the connecting portion between the crankcase 1 and the cylinder block 2. A variable compression ratio mechanism A is provided. When the volume of the combustion chamber when the piston is located at the compression top dead center is referred to as the combustion chamber volume, the mechanical compression ratio is a value that is mechanically determined only from the piston stroke volume and the combustion chamber volume during the compression stroke. (Combustion chamber volume + stroke volume) / combustion chamber volume.

  The electronic control unit 30 is composed of a digital computer, and is connected to each other by a bidirectional bus 31. A ROM (read only memory) 32, a RAM (random access memory) 33, a CPU (microprocessor) 34, an input port 35 and an output port 36. It comprises. The output signal of the intake air amount detector 18 and the output signal of the air-fuel ratio sensor 21 are input to the input port 35 via corresponding AD converters 37, respectively. A load sensor 41 that generates an output voltage proportional to the depression amount L of the accelerator pedal 40 is connected to the accelerator pedal 40, and the output voltage of the load sensor 41 is input to the input port 35 via the corresponding AD converter 37. Is done. Further, a crank angle sensor 42 that generates an output pulse every time the crankshaft rotates, for example, 30 ° is connected to the input port 35. Further, a position sensor 43 for detecting the relative position of the cylinder block 2 with respect to the crankcase 1 is provided, and the output voltage of the position sensor 43 is input to the input port 35 via the corresponding AD converter 37. On the other hand, the output port 36 is connected to the spark plug 6, the fuel injection valve 13, the throttle valve drive actuator 16, and the variable compression ratio mechanism A through a corresponding drive circuit 38.

  2 is an exploded perspective view of the variable compression ratio mechanism A shown in FIG. 1, and FIG. 3 is a side sectional view of the internal combustion engine schematically shown. Referring to FIG. 2, a plurality of protrusions 50 spaced from each other are formed below both side walls of the cylinder block 2, and cam insertion holes 51 each having a circular cross section are formed in each protrusion 50. Has been. On the other hand, a plurality of protrusions 52 are formed on the upper wall surface of the crankcase 1 so as to be fitted between the corresponding protrusions 50 spaced apart from each other. Cam insertion holes 53 each having a circular cross section are formed.

  The variable compression ratio mechanism A includes an operator. In the example shown in FIG. 2, the operating element is composed of a pair of camshafts 54, 55, and circular cams 56 are rotatably inserted into the respective cam insertion holes 51 on the respective camshafts 54, 55. Is fixed. These circular cams 56 are coaxial with the rotational axes of the camshafts 54 and 55. On the other hand, an eccentric shaft 57 arranged eccentrically with respect to the rotation axis of each camshaft 54, 55 extends between the circular cams 56 as shown by hatching in FIG. A cam 58 is eccentrically mounted for rotation. As shown in FIG. 2, the circular cams 58 are disposed between the circular cams 56, and the circular cams 58 are rotatably inserted into the corresponding cam insertion holes 53.

  When the circular cams 56 fixed on the camshafts 54 and 55 are rotated in opposite directions as indicated by solid arrows in FIG. 3A from the state shown in FIG. In order to move toward the lower center, the circular cam 58 rotates in the opposite direction to the circular cam 56 in the cam insertion hole 53 as shown by the broken arrow in FIG. 3A, and is shown in FIG. As described above, when the eccentric shaft 57 moves to the lower center, the center of the circular cam 58 moves below the eccentric shaft 57.

  3A and 3B, the relative positions of the crankcase 1 and the cylinder block 2 are determined by the distance between the center of the circular cam 56 and the center of the circular cam 58. The cylinder block 2 moves away from the crankcase 1 as the distance between the center and the center of the circular cam 58 increases. When the cylinder block 2 moves away from the crankcase 1, the combustion chamber volume increases. Therefore, the combustion chamber volume or the mechanical compression ratio can be changed by rotating the camshafts 54 and 55.

  As shown in FIG. 4, gears 59 and 60 are fixed to the ends of the camshafts 54 and 55, respectively. The variable compression ratio mechanism A further includes an input actuator 61 that generates an input torque for rotating the camshafts 54 and 55. In the embodiment shown in FIG. 4, the input actuator 61 is constituted by an electric motor. The output shaft 61 i of the input actuator 61 is coupled to the gear 59 via the reverse input cutoff clutch 62 and the gear train 63, and the gear 59 is coupled to the gear 60 via the gear train 64. Therefore, when the input actuator 61 is rotated, the camshafts 54 and 55 are rotated in opposite directions. In this embodiment, by driving the input actuator 61, the combustion chamber volume or the mechanical compression ratio can be changed over a wide range. The variable compression ratio mechanism A shown in FIGS. 1 to 4 shows an example, and any type of variable compression ratio mechanism can be used. In the variable compression ratio mechanism in which the operator reciprocates linearly, the operator is connected to the reverse input cutoff clutch through a mechanism that converts linear motion into rotational motion.

  The reverse input cut-off clutch 62 is for transmitting input torque from the input actuator 61 to the camshafts 54, 55 and cutting off reverse input torque from the camshafts 54, 55 to the input actuator 61.

  As shown in FIGS. 5 and 6, the reverse input cutoff clutch 62 includes, for example, a cylindrical fixing member 70 fixed to the engine body 1, an input member 71 that can rotate about the axis L with respect to the fixing member 70, An output member 72 that is rotatable about an axis L with respect to the fixed member 70. In FIG. 5, reference numeral 73 indicates a bearing. The input member 71 is connected to the output shaft 61 i of the input actuator 61, and the output member 72 is connected to the camshafts 54 and 55 via gear trains 63 and 64.

  An annular clearance 74 is formed between the inner peripheral surface of the fixing member 70 and the outer peripheral surface of the output member 72, and the wedge member 75 extends in the clearance 74 between the locked position LP and the unlocked position ULP in the circumferential direction. It is arranged to be movable. In the embodiment according to the present invention, the wedge member 75 is composed of a pair of wedge members 75L and 75R, and four pairs of wedge members are arranged in the clearance 74 at equal intervals in the circumferential direction. In the embodiment shown in FIGS. 5 and 6, each wedge member is constituted by a cylindrical roller.

  As shown in FIG. 6, the inner peripheral surface of the fixing member 70 is a cylindrical surface. On the other hand, the outer peripheral surface of the output member 72 is formed so that the lock position LP and the non-lock position ULP are alternately provided in the clearance 74 in the circumferential direction. That is, at the lock position LP, the outer peripheral surface of the output member 72 protrudes toward the fixing member 70, and the radial width of the clearance 74 is smaller than the diameter of the wedge members 75L and 75R. As a result, when the wedge member 75L is in the lock position LP, the wedge member 75L comes into contact with both the output member 72 and the fixing member 70, and the output member 72 is prevented from rotating in the direction DR. Similarly, when the wedge member 75R is in the lock position LP, the wedge member 75R comes into contact with both the output member 72 and the fixing member 70, and the output member 72 is prevented from rotating in the direction DL. A compression spring 76 is provided between the wedge members 75L and 75R, and the wedge members 75L and 75R are urged toward the corresponding lock positions LP by the compression spring 76, respectively.

  On the other hand, at the unlocked position ULP, the outer peripheral surface of the output member 72 is separated from the fixing member 70, and the radial width of the clearance 74 is larger than the diameter of the wedge members 75L and 75R. As a result, when the wedge member 75L is in the unlocked position ULP, the output member 72 is allowed to rotate in the direction DR. Similarly, when the wedge member 75R is in the unlocked position ULP, the output member 72 is allowed to rotate in the direction DL. The output member 72 is allowed to rotate in the direction DR even when the wedge member 75R is in the lock position LP, and the output member 72 is rotated in the direction DL even when the wedge member 75L is in the lock position LP. Is allowed.

  Further, a contact portion 77 is formed integrally with the input member 71, and this contact portion 77 is located in the clearance 74. As a result, when the input member 71 is rotated, the contact portion 77 can contact the wedge members 75L and 75R. In the neutral state shown in FIG. 6, a circumferential play 78 is provided between the wedge members 75 </ b> L and 75 </ b> R and the contact portion 77.

  The input member 71 is integrally formed with a convex portion 79, the output member 72 is integrally formed with a concave portion 80, and the convex portion 79 is accommodated in the concave portion 80. As a result, when the input member 71 is rotated, the convex portion 78 forms a concave portion in the input member 71 and the convex portion in the output member 72 in another embodiment. In the neutral state shown in FIG. 6, a circumferential play 81 is provided between the convex portion 79 and the inner wall surface of the concave portion 80. The play 81 is set larger than the play 78.

  In the embodiment according to the present invention, when the output member 72 is rotated in the direction DR, the cylinder block 2 is moved away from the crankcase 1, and the mechanical compression ratio is thus lowered. Further, when the output member 72 is rotated in the direction DL, the cylinder block 2 is moved in a direction approaching the crankcase 1, and thus the mechanical compression ratio is increased. On the other hand, the reverse input torque due to the combustion pressure acts on the output member 72 in the direction DR. Further, reverse input torque due to the weight of the cylinder block 2 acts on the output member 72 in the direction DL.

  FIG. 6 shows a state where the mechanical compression ratio should be maintained. In this state, the wedge members 75L and 75R are held at the respective lock positions LP by the compression springs 76. As a result, even if a reverse input torque in the direction DR acts on the output member 72 from the camshafts 54 and 55, the output member 72 is prevented from rotating by the wedge member 75L, so that the input member 71 is rotated in the direction DR. Is prevented. Even if reverse input torque in the direction DL acts on the output member 72, the wedge member 75R prevents the output member 72 from rotating in the direction DL, and accordingly prevents the input member 71 from rotating.

  When the mechanical compression ratio is to be decreased, the input member 71 is rotated in the direction DR by the input actuator 61. As a result, as shown in FIG. 7, the contact portion 77 contacts the wedge member 75L, and the wedge member 75L is moved from the lock position LP to the non-lock position ULP. Since the play 81 is larger than the play 78, the convex portion 79 is not engaged with the concave portion 80 at this time.

  When the input member 71 is further rotated in the direction DR, the convex portion 79 engages with the concave portion 80 as shown in FIG. As a result, the input torque from the input member 71 is transmitted to the output member 72, and thus the output member 72 is rotated in the direction DR.

  Next, when the operation of the input actuator 61 is stopped, the wedge member 75L is returned to the lock position LP by the compression spring 76.

  When the mechanical compression ratio is to be increased, the input member 71 is rotated in the direction DL by the input actuator 61. As a result, the contact portion 77 contacts the wedge member 75R, and the wedge member 75R is moved from the lock position LP to the non-lock position ULP. When the input member 71 is further rotated in the direction DL, the convex portion 79 engages with the concave portion 80. As a result, the input torque from the input member 71 is transmitted to the output member 72, and thus the output member 72 is rotated in the direction DL. Next, when the operation of the input actuator 61 is stopped, the wedge member 75R is returned to the lock position LP by the compression spring 76.

  Now, in the embodiment according to the present invention, as shown in FIG. 9, a relative movement suppressor 90 capable of suppressing the relative movement between the crankcase 1 and the cylinder block 2 between the crankcase 1 and the cylinder block 2. Is provided.

  In the embodiment shown in FIG. 9, the relative movement suppressor 90 is constituted by a hydraulic actuator that can extend in the axial direction. When the relative movement suppressor 90 is actuated, that is, extended in the axial direction, the frictional force between the relative movement suppressor 90 and the crankcase 1 and the cylinder block 2 is increased, so that the crankcase 1 and the cylinder block are increased. The relative movement between the two is suppressed. On the other hand, when the relative movement suppressor 90 is deactivated, that is, contracted in the axial direction, the frictional force between the relative movement suppressor 90 and the crankcase 1 and the cylinder block 2 is reduced. The relative movement between the case 1 and the cylinder block 2 is easily performed. In this case, the relative movement suppressor 90 also has a function of guiding the cylinder block 2. In FIG. 9, reference numeral 91 denotes a compression spring disposed between the crankcase 1 and the cylinder block 2.

  Now, as shown in FIGS. 7 and 8, when the wedge member 75L is in the unlocked position ULP, the output member 72 is rotatable in the direction of action DR of the reverse input torque due to the combustion pressure. At this time, if reverse input torque acts on the output member 72 in the direction DR, as shown in FIG. 10, the output member 72 may rotate in the direction DR, and the wedge member 75L may be positioned at the lock position LP. Next, the wedge member 75L may be moved to the unlocked position ULP by the contact portion 77. As a result, the wedge member 75L may reciprocate between the lock position LP and the non-lock position ULP. In this case, when the wedge member 75L is moved to the locked position LP and the non-locked position ULP, if it collides violently with the fixed member 70, the contact portion 77 of the input member 71, or the output member 72, undesirable noise and vibration are generated. There is a risk.

  Therefore, in the embodiment according to the present invention, the relative movement suppressor 90 is operated when noise or vibration due to the wedge member 75L becomes a problem, and the relative movement between the crankcase 1 and the cylinder block 2 is suppressed. As a result, even if reverse input torque due to combustion pressure acts on the crankcase 1 and the cylinder block 2, the relative movement between the crankcase 1 and the cylinder block 2 is suppressed, so that the output member 72 rotates in the direction DR. Is suppressed. Therefore, the wedge member 75L is prevented from being positioned again at the lock position LP, or the wedge member 75L is prevented from violently colliding with the fixing member 70, the abutting portion 77 of the input member 71, or the output member 72. . Therefore, undesirable noise and vibration can be suppressed.

  In the embodiment according to the present invention, as shown in FIG. 11, the engine operating state determined by the engine load factor KL and the engine speed Ne is divided into a low load region LLA, a medium load region MLA, and a high load region HLA. In the low load region LLA, the engine load factor KL is lower than a predetermined first set load factor KL1. In the medium load region MLA, the engine load factor KL is higher than the first set load factor KL1 and lower than a predetermined second set load factor KL2 (> KL1). In the high load region HLA, the engine load factor KL is higher than the second set load factor KL2. In the example shown in FIG. 11, the first set load factor KL1 is substantially constant regardless of the engine speed Ne, and the second set load factor KL2 decreases as the engine speed Ne increases. The engine load factor KL is the ratio of the engine load to the total load.

  When the engine operating state is in the low load region LLA, the reverse input torque due to the combustion pressure is relatively small, so that the noise and vibration that can be generated by the wedge member 75L are relatively small. Further, when the engine operating state is within the high load region HLA, noise and vibration that can be generated by the wedge member 75L are relatively small compared to noise and vibration caused by engine operation.

  On the other hand, FIG. 12 increases the link angle θ of the link (FIG. 2) formed by the circular cams 56 and 58 of the camshafts 54 and 55 and the eccentric shaft 57 from 0 degrees to 180 degrees while maintaining the engine operating state. The change of the reverse input torque TQR which acts on the output member 72 when it is made to show is shown. Here, as shown in FIG. 13, the link angle θ is an angle formed by the moving axis of the circular cam 56, that is, the cylinder block 2, and the line segment from the rotational axis of the circular cam 56 toward the eccentric shaft 57, and θ = 0. The cylinder block 2 is in the lowermost position at the time, and the cylinder block 2 is in the uppermost position when θ = 180. The relative position of the cylinder block 2 with respect to the crankcase 1 detected by the position sensor 43 (FIG. 1) represents the link angle θ.

  As shown in FIG. 12, when the link angle θ is in the region X, the reverse input torque TRQ becomes higher than the allowable upper limit TQRU. On the other hand, when the link angle θ is outside the region X, the reverse input torque TRQ becomes lower than the allowable upper limit TQRU.

  Therefore, in the embodiment according to the present invention, the relative movement suppressor 90 is operated when the engine operating state is in the medium load region MLA and the link angle θ is in the region X. As a result, noise and vibration due to the wedge member 75L can be suppressed.

  On the other hand, when the engine operating state is in the low load region LLA or the high load region HLA, or the link angle θ is outside the region X even if the engine operating state is in the medium load region MLA, the relative movement is suppressed. The instrument 90 is deactivated. As a result, a large input torque is not required to move the output member 72 to change the mechanical compression ratio. Further, the responsiveness of the reverse input cutoff clutch 62, that is, the responsiveness of the movement of the output member 72 to the input of the input torque is maintained high.

  Thus, in the embodiment according to the present invention, the operation and stop of the relative movement suppressor 90 are selectively switched, that is, the relative movement suppressor 90 is not always operated.

  FIG. 14 shows a routine for executing the relative movement suppression control. This routine is executed by interruption at regular intervals.

  Referring to FIG. 14, in step 101, it is determined whether or not the mechanical compression ratio ε should be reduced. When the mechanical compression ratio ε is to be lowered, the routine proceeds to step 102 where it is determined whether or not the engine operating state is within the medium load region MLA shown in FIG. When the engine operating state is within the medium load area MLA, the routine proceeds to step 103 where it is determined whether or not the link angle θ is within the area X shown in FIG. When the link angle θ is within the region X, the routine proceeds to step 104 where the relative movement suppressor 90 is activated. On the other hand, when the mechanical compression ratio ε should not be reduced in step 101, when the engine operating state is outside the medium load region MLA in step 102, or when the link angle θ is outside the region X in step 103, then step Proceeding to 105, the relative movement suppressor 90 is deactivated.

  In another embodiment according to the present invention, step 102 in the flowchart of FIG. 14 is omitted. That is, the relative movement suppressor 90 is operated when the link angle θ is within the region X regardless of the engine operating state. In yet another embodiment according to the present invention, step 103 in the flowchart of FIG. 14 is omitted. That is, regardless of the link angle θ, the relative movement suppressor 90 is operated when the engine operating state is in the medium load region MLA.

  Furthermore, in the first modification according to the present invention, the relative movement suppressor 90 is operated when the engine operating state is outside the low load region LLA, and the relative movement suppression is performed when the engine operating state is within the low load region LLA. The instrument 90 is deactivated. In the second modification according to the present invention, the relative movement suppressor 90 is operated when the engine operating state is outside the high load region HLA, and the relative movement suppressor 90 is operated when the engine operating state is within the high load region HLA. Is deactivated.

  In the description so far, relative movement suppression control is performed when the reverse input torque acts in the direction DR when the output member 72 is rotated in the direction DR in order to change the mechanical compression ratio. However, when the output member 72 is rotated in the direction DL in order to change the mechanical compression ratio, the relative movement suppression control can be similarly performed when the reverse input torque acts in the direction DL.

DESCRIPTION OF SYMBOLS 1 Crankcase 2 Cylinder block 4 Piston 5 Combustion chamber A Variable compression ratio mechanism 61 Input actuator 62 Reverse input interruption | blocking clutch 70 Fixed member 71 Input member 72 Output member 74 Clearance 75 Wedge member 90 Relative movement inhibitor LP Lock position ULP Unlock position

Claims (3)

  The variable compression ratio mechanism includes a variable compression ratio mechanism that can change the mechanical compression ratio by relatively moving the cylinder block and the crankcase, and the variable compression ratio mechanism is an input actuator that generates an input torque for moving the operation element. And a reverse input cutoff clutch disposed between the operator and the output shaft of the input actuator for transmitting input torque from the input actuator to the operator and blocking reverse input torque from the operator to the input actuator, The mechanical compression ratio is changed by moving the operating element, and the reverse input cutoff clutch includes a fixed member, an input member connected to the input actuator, an output member connected to the operating element, and an output member A wedge member movable between a locking position and an unlocking position between the locking member and the fixing member, and the wedge member is in the locking position Prevents the output member from moving in the direction of the reverse input torque, and when the wedge member is in the unlocked position, the output member is allowed to move in the direction of the reverse input torque and changes the mechanical compression ratio. Therefore, when the input member is moved in the direction of the reverse input torque, the wedge member is moved from the locked position to the unlocked position, and when the input member is further moved in the direction of the reverse input torque, the input member becomes the output member. A variable compression ratio internal combustion engine in which the output member is engaged and moved together with the operation element, and relative movement between the cylinder block and the crankcase can be suppressed between the cylinder block and the crankcase. A variable compression ratio internal combustion engine provided with a relative movement suppressor, wherein the operation and stop of the relative movement suppressor are selectively switched.   The variable compression according to claim 1, wherein the relative movement suppressor is activated when the engine operating state is in the medium load region, and the relative movement suppressor is deactivated when the engine operating state is outside the medium load region. Specific internal combustion engine.   The variable compression according to claim 1, wherein the relative movement suppressor is activated when the reverse input torque is higher than the allowable upper limit value, and the relative movement suppressor is deactivated when the reverse input torque is lower than the allowable upper limit value. Specific internal combustion engine.

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