JP2009222024A - Variable cam phase internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable cam phase internal combustion engine can surely lock a VTC actuator at a prescribed cam phase in starting of the engine. <P>SOLUTION: A lock pin 33 and a lock pin spring 34 are stored in a third vane 43 and a lock hole 25a in which the rock pin 33 is fitted is bored on a back plate 25. A rotation restriction pin 36 and a restriction pin spring 37 are stored in a fourth vane 43 and an arch shape rotation restriction groove 25b in which the rotation restriction pin 36 is fitted is bored on the back plate 25. A rotation restriction range θ2(a rotation range of a housing 22 and a rotor 23 when the rotation restriction pin 36 is fitted in the rotation restriction groove 25b) is 20°(40° in crank angle), and is set significantly smaller than a maximum rotation range θ1(35° in this embodiment(70° in crank angle)) of the housing 22 and the rotor 23. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cam phase variable internal combustion engine, and more particularly to a technique for reliably locking a VTC actuator with a predetermined cam phase when the engine is started.

  Many 4-cycle engines (hereinafter simply referred to as engines) are equipped with various variable valve mechanisms to improve output and fuel consumption, reduce harmful exhaust gas components, and the like. As a variable valve mechanism, there is a conventional one that switches between a low speed type cam and a high speed type cam. In recent years, however, the cam phase and the valve lift are individually and continuously controlled to further improve the transient characteristics and the throttle. What has become less is becoming mainstream. A valve timing control device (Variable Timing Control Device: hereinafter referred to as VTC) used for variable control of the cam phase is a hydraulic actuator (hereinafter referred to as VTC actuator) installed near the end of the camshaft in the cylinder head. And a linear solenoid for controlling the hydraulic pressure (engine hydraulic pressure) supplied to the VTC actuator (see Patent Documents 1 and 2).

The VTC actuators of Patent Documents 1 and 2 include a rotor having a plurality of vanes and a housing that accommodates the rotor in a relatively rotatable manner, and hydraulic oil ( When the engine oil is appropriately supplied, the rotor and the housing rotate relative to each other. The rotor is fixed to the camshaft, and the cam sprocket is integrated with the housing. In this type of VTC actuator, the hydraulic pressure in the advance chamber and retard chamber is lost when restarting after the engine is stopped. Therefore, in the VTC actuator of Patent Document 2, the spring-driven lock pin installed on the rotor is inserted into the lock hole formed in the housing when the engine is stopped, so that the most advanced angle side and the most retarded angle side are provided. The engine is restarted while being locked at the cam phase (intermediate cam phase).
JP 2002-285872 A JP 2001-50063 A

  In the VTC actuator of Patent Document 2, when an engine stall due to an unexpected cause or a sudden drop in engine oil pressure occurs, it is not possible to secure a sufficient time for the lock pin to fit into the lock hole. There is a possibility that the actuator remains moving to the most retarded angle side, for example. When the engine is started in this state, noise due to camshaft rampage, increase in harmful exhaust gas components due to incorrect valve timing, engine misfire, etc. occur until the engine hydraulic pressure rises sufficiently There was a fear.

  The present invention has been made in view of the above situation, and an object thereof is to provide a variable cam phase internal combustion engine in which a VTC actuator is reliably locked at a predetermined cam phase when the engine is started.

  According to a first aspect of the present invention, there is provided a first rotating member that rotates in synchronization with a crankshaft, a second rotating member that rotates integrally with a camshaft and is rotatably coupled to the first rotating member, and the first A cam phase variable internal combustion engine having a driving means for relatively rotating a rotating member and the second rotating member within a predetermined first angle range, wherein the relative rotation between the first rotating member and the second rotating member Relative rotation limiting means for limiting the rotation within a second angle range narrower than the first angle range, and coupling the first rotation member and the second rotation member with a predetermined coupling angle within the second angle range / And an integrated cam phase fixing means.

  According to a second aspect of the present invention, in the cam phase variable internal combustion engine according to the first aspect of the invention, the coupling angle is set at one end of the second angle range.

  According to a third aspect of the invention, in the cam phase variable internal combustion engine according to the first or second aspect of the invention, the relative rotation restricting means is held on either the first rotating member or the second rotating member. And a rotation limiting groove formed on one of the first rotating member and the second rotating member and into which the stopper member is fitted, and the operating direction of the stopper member is the camshaft of the camshaft. It is characterized by being substantially parallel to the axis.

  According to a fourth aspect of the invention, in the cam phase variable internal combustion engine according to the first or second aspect of the invention, the relative rotation restricting means is held on either the first rotating member or the second rotating member. And a rotation limiting groove formed on one of the first rotating member and the second rotating member and into which the stopper member is fitted, and the operating direction of the stopper member is the camshaft of the camshaft. It is characterized by being substantially orthogonal to the axis.

  According to a fifth aspect of the present invention, in the cam phase variable internal combustion engine according to the fourth aspect of the present invention, the stopper member includes a centrifugal force accompanying the rotation of the first rotating member or the second rotating member, and pressure oil supply means. It is driven by at least one of hydraulic oil supplied from

  According to the first aspect of the invention, for example, when the engine hydraulic pressure is lowered, first, the first rotation member and the second rotation member are relatively rotated within the first angle range by the operation of the relative rotation limiting means. Thereafter, the first rotating member and the second rotating member are coupled / integrated at a predetermined relative angle by the operation of the cam phase fixing means. According to the second aspect of the present invention, even when the first rotating member and the second rotating member are alternately rotated relative to each other in both the forward and reverse directions within the second angle range, the cam phase fixing means is once at the coupling angle. It is braked and it becomes easy to couple | bond with a 1st rotation member and a 2nd rotation member. According to the third invention, the centrifugal force accompanying the rotation of the first rotating member and the second rotating member is less likely to act on the stopper member, and the first rotating member and the second rotating member by the cam phase fixing means Bonding is performed smoothly. Further, according to the fourth and fifth inventions, it is possible to reduce the parts required for driving the stopper member by utilizing the centrifugal force accompanying the rotation of the first rotating member and the second rotating member.

  Hereinafter, an embodiment of a cam phase variable internal combustion engine according to the present invention and a partial modification thereof will be described in detail with reference to the drawings.

[Embodiment]
FIG. 1 is a perspective view of a main part of an automotive engine according to the embodiment, FIG. 2 is an exploded perspective view of the VTC actuator according to the embodiment, and FIG. 3 is a schematic configuration diagram of the VTC actuator according to the embodiment. 4 is an exploded perspective view of the main part of the VTC actuator according to the embodiment, FIG. 5 is an exploded perspective view of the main part of the VTC actuator according to the embodiment, and FIG. 6 shows the relative relationship between the housing and the rotor according to the embodiment. It is explanatory drawing which shows a rotation range.

<< Configuration of Embodiment >>
<Overall configuration>
An engine (cam phase variable internal combustion engine) E shown in FIG. 1 is a DOHC 4-valve four-cycle in-line four-cylinder gasoline engine mounted on an automobile. An intake valve 2 for each cylinder is provided in the cylinder head 1. And an exhaust valve 3, an intake camshaft 4 and an exhaust camshaft 5 that drive the intake and exhaust valves 2 and 3. Both camshafts 4 and 5 are rotationally driven by the crankshaft 10 at a rotational speed of 1/2 through the crank sprocket 6, the cam chain 7, the intake cam sprocket 8, and the exhaust cam sprocket 9. The crankshaft 10 is connected to the piston 12 via a connecting rod 11 and drives an oil pump 14 installed obliquely downward via a chain 13. A VTC actuator 21 is attached to the front end of the intake camshaft 4, and an oil passage 16 for supplying hydraulic oil (engine oil) from the oil pump 14 to the VTC actuator 21 is provided in the cylinder head 1 and the cylinder block 15. Is formed.

<VTC actuator>
As shown in FIG. 2, the VTC actuator 21 includes a housing (first rotating member) 22 having an intake cam sprocket 8 formed on the outer periphery thereof, is rotatably held in the housing 22, and is then attached to the front end of the intake camshaft 4. A rotor (second rotating member) 23 to which the surface is fastened, a front plate 24 covering the front surface of the housing 22, a back plate 25 covering the rear surface of the housing 22, a reed valve 26 disposed on the inner peripheral side of the front plate 24, a lead A reed valve cover 27 for fixing the valve 26 to the rotor 23, a bias spring 28 for relatively rotating the housing 22 and the rotor 23 in the advance direction, a valve sleeve 29 held at the axis of the intake camshaft 4 and the rotor 23, Spool valve (hydraulic control valve) slidably fitted in the valve sleeve 29 30, a linear solenoid 31 that drives the spool valve 30 in the axial direction by being controlled by the engine ECU, a return spring 32 that biases the spool valve 30 toward the linear solenoid 31, and a lock pin (cam phase) held by the rotor 23 Fixing means) 33, a lock pin spring 34 that urges the lock pin 33 toward the back plate 25, and a check valve 35 that is held by the rotor 23 and prevents backflow of hydraulic oil from the oil passage in the rotor 23 to the oil passage 16. The main components are a rotation limit pin (stopper member) 36 held by the rotor 23 and a limit pin spring 37 that biases the rotation limit pin 36 toward the back plate 25.

  As shown in FIG. 3, relatively thin first and second vanes 41 and 42 and relatively thick width third and fourth vanes 43 and 44 are erected on the outer periphery of the rotor 23. Formed on the inner periphery of the housing 22 are first to fourth vane chambers 45 to 48 for accommodating these vanes 41 to 44 so as to be relatively rotatable at a predetermined angle (35 ° in this embodiment). In the present embodiment, the first vane 41 and the first vane chamber 45 are constituent elements of a first hydraulic pressure actuated phaser (hereinafter referred to as OPA) 61, The two-vane chamber 46 is a component of the second OPA 62, and the third vane 43 and the third vane chamber 47 are components of a cam torque-driven phase variable mechanism (hereinafter referred to as CTA) 63. In FIG. 3, a member denoted by reference numeral 49 is a rotor-side seal provided on the outer periphery of the rotor 23, and a member denoted by reference numeral 50 is a housing-side seal provided on the inner periphery of the housing 22.

  The first and second vane chambers 45 and 46 are advanced-angle-side hydraulic chambers 45a to which hydraulic oil from the spool valve 30 is supplied via supply oil passages 51 and 52 by the first and second vanes 41 and 42, respectively. 46a and retarding chambers 45b and 46b communicating with the drain passages 53 and 54, respectively. Further, the third vane chamber 47 is connected to the advance angle hydraulic chamber 47 a communicating with the spool valve 30 via the advance angle side oil passage 56 by the third vane 43 and the spool valve 30 via the retard angle side oil passage 55. And a retarded-side hydraulic chamber 47b that communicates with each other.

<Lock pin and rotation limit pin>
As shown in FIGS. 4 and 5, the lock pin 33 and the lock pin spring 34 (see FIG. 2) are accommodated in the third vane 43, while the lock hole into which the lock pin 33 is fitted in the back plate 25. 25a is drilled. The fourth vane 43 accommodates a rotation limiting pin 36 and a limiting pin spring 37 (see FIG. 2), while the back plate 25 has an arcuate rotation limiting groove 25b into which the rotation limiting pin 36 is fitted. It is installed. In the case of the embodiment, the lock pin 33 and the rotation limiting pin 36 are arranged so that the centrifugal force accompanying the rotation of the intake camshaft 4 hardly acts during operation of the engine E so that the shaft center of the VTC actuator 21 (that is, the intake camshaft 4 It is installed parallel to the axis of

  As will be described later, the lock pin 33 can be fitted into the lock hole 25a by the spring force of the lock pin spring 34 only when the hydraulic pressure in the CTA 63 is lowered. Further, only when the hydraulic pressure supplied to the VTC actuator 21 is lowered, the rotation limit pin 36 can be inserted into the rotation limit groove 25b by the spring force of the limit pin spring 37. In the case of this embodiment, the release pressure of the lock pin 33 (hydraulic pressure at which insertion into the lock hole 25a starts) is set to 50 kPa, and the release pressure of the rotation limit pin 36 is set to 35 kPa. Further, the lock pin 33 has a lock hole at a relative angle (coupling angle: an intermediate angle between the most advanced angle and the most retarded angle in this embodiment) at which a cam phase suitable for starting (starting cam phase) is obtained. 25a.

  As shown in FIG. 6, the rotation restriction range θ2 (the rotation range of the housing 22 and the rotor 23 when the rotation restriction pin 36 is fitted in the rotation restriction groove 25b: the second angle range) is 20 ° (40 at the crank angle). °)), and is set to be significantly smaller than the maximum rotation range θ1 of the housing 22 and the rotor 23 (in this embodiment, 35 ° (70 ° in crank angle): first angle range). In the rotation restriction range θ2, the end on the advance side coincides with the most advanced position of the maximum rotation range θ1, and the end on the retard side coincides with the coupling angle.

<< Operation of Embodiment >>
Hereinafter, the operation of the present embodiment will be described with reference to schematic diagrams and graphs of FIGS.
<Advance operation>
When the intake camshaft 4 is advanced during operation of the engine E, the engine ECU moves the spool valve 30 to the advanced position (rightward in the figure) by the linear solenoid 31 as shown in FIG. Then, the hydraulic oil supplied from the oil pump 14 via the oil passage 16 flows into the advance side hydraulic chambers 45a and 46a on the first and second OPA 61 and 62 side via the spool valve 30 and enters the first and second hydraulic chambers 45a and 46a. The second vanes 41 and 42 are urged toward the advance side. On the other hand, in the CTA 63, the cam angle on the advance side acts on the intake camshaft 4, and the second valve body 26b of the reed valve 26 opens each time the rotor 23 rotates relative to the housing 22 toward the advance side. The hydraulic oil in the side hydraulic chamber 47b flows into the advance side hydraulic chamber 47a and relatively rotates the third vane 43 (that is, the rotor 23) to the advance side. Further, when the retard side cam torque is applied, the first and second valve bodies 26a, 26b of the reed valve 26 are closed, and the cam phase is maintained without moving the hydraulic oil. By the operations of the first and second OPAs 61 and 62 and the CTA 63, the rotor 23 rotates relative to the housing 22 in the clockwise direction in the drawing, and the intake camshaft 4 advances. The supply of hydraulic oil to the CTA 63 is performed until the CTA 63 is satisfied via the check valve 35 at the start of operation of the engine E. Further, during normal operation of the engine E, the lock pin 33 is moved to the release side by the hydraulic pressure supplied from the CTA 63 (disengaged from the lock hole 25a), and the rotation limit pin 36 is released from the hydraulic pressure supplied from the oil passage 16. (Disengagement from the rotation limiting groove 25b), the housing 22 and the rotor 23 can be relatively rotated within the maximum rotation range θ1.

<Delayed operation>
When retarding the intake camshaft 4 during operation of the engine E, the engine ECU moves the spool valve 30 to the retarded position (leftward in the figure) by the linear solenoid 31, as shown in FIG. Then, in the first and second OPAs 61 and 62, the hydraulic oil in the advance side hydraulic chambers 45 a and 46 a is discharged from the drain passages 53 and 54 via the spool valve 30 and advances through the first and second vanes 41 and 42. There is no urging force to urge the corner. On the other hand, in the CTA 63, the retard cam torque acts on the intake camshaft 4, and the first valve body 26a of the reed valve 26 opens and advances each time the rotor 23 rotates relative to the housing 22 toward the retard side. The hydraulic oil in the side hydraulic chamber 47a flows into the retarded side hydraulic chamber 47b and relatively rotates the third vane 43 (that is, the rotor 23) toward the retarded side. Further, when the cam torque on the advance side acts, the first and second valve bodies 26a, 26b of the reed valve 26 are closed, and the cam phase is maintained without moving the hydraulic oil. By the operation of the first and second OPAs 61 and 62 and the CTA 63, the rotor 23 rotates relative to the housing 22 counterclockwise in the figure, and the intake camshaft 4 is retarded.

<Holding operation>
When the target cam phase is obtained by the advance angle operation or the retard angle operation described above, the engine ECU moves the spool valve 30 to the holding position (center in the figure) by the linear solenoid 31 as shown in FIG. . Then, in the first and second OPAs 61 and 62, the hydraulic oil in the advance side hydraulic chambers 45a and 46a is sealed by the spool valve 30, and the first and second vanes 41 and 42 cannot move. On the other hand, in the CTA 63, the hydraulic oil cannot move between the advance side hydraulic chamber 47a and the retard side hydraulic chamber 47b, and the third vane 43 cannot move. By the operations of the first and second OPAs 61 and 62 and the CTA 63, the rotor 23 does not rotate relative to the housing 22, and the cam phase of the intake camshaft 4 is maintained.

<Operation when stopped>
When the driver turns off the ignition key to stop the engine E, the current supply from the engine ECU to the linear solenoid 31 is cut off, and at the same time, the rotational speed of the engine E rapidly decreases. Then, as shown in FIG. 10, the hydraulic oil supplied to the rotation limit pin 35 is discharged, and the rotation limit pin 35 is biased toward the back plate 25 by the spring force of the limit pin spring 36. Further, in the CTA 63, hydraulic fluid leaks from the gap between the rotor 23 and the housing 22 and the CTA hydraulic pressure is lowered, and the lock pin 33 is also biased toward the back plate 25 by the spring force of the lock pin spring 34. Will come to be. On the other hand, in the first and second OPAs 61 and 62, when the spool valve 30 moves to the retard position, the hydraulic oil in the advance side hydraulic chambers 45a and 46a is discharged from the drain passages 53 and 54 via the spool valve 30. Is done. Further, in the CTA 63, the hydraulic oil in the advance side hydraulic chamber 47a and the retard side hydraulic chamber 47b decreases relatively rapidly due to the leak described above, and the third vane 43 (that is, the rotor 23) is relative to the housing 22. You can rotate. Thereby, the rotor 23 and the housing 22 are alternately rotated relative to each other between the advance side and the retard side by the cam torque received by the intake camshaft 4, and the rotation limit pin 36 first biased by the limit pin spring 37. Is inserted into the rotation restricting groove 25b, the lock pin 33 biased by the lock pin spring 34 is inserted into the lock hole 25a, and the rotor 23 and the housing 22 are locked.

  As shown in FIG. 11, when the engine E is stopped, the supply hydraulic pressure to the VTC actuator 21 decreases relatively quickly as the engine rotation speed decreases, so the supply hydraulic pressure falls below the release pressure (35 kPa). At that time, the rotation limit pin 36 engages with the rotation limit groove 25b, and the relative rotation range between the housing 22 and the rotor 23 shifts from the maximum rotation range θ1 to the rotation limit range θ2. Next, when the CTA hydraulic pressure applied to the lock pin 33 is reduced due to the leakage of hydraulic oil from the CTA 63 and the CTA hydraulic pressure falls below the release pressure (50 kPa), the lock pin 33 is moved to the back plate 25 side by the lock pin spring 34. Be energized by. Since the end of the rotation limit range θ2 on the retarded angle side coincides with the coupling angle, the moment when the housing 22 and the rotor 23 rotate relative to each other alternately in the rotation limit range θ2 and stop momentarily on the most retarded angle side. (In other words, at the moment when the relative rotation direction is reversed), the lock pin 33 is fitted into the lock hole 25a, and the housing 22 and the rotor 23 are coupled / integrated.

<Operation at restart>
When the driver sets the ignition key to START after the automobile has been stopped for a long time, the engine E starts smoothly because the intake camshaft 4 is fixed at the start cam phase. Then, as shown in FIG. 12, the hydraulic oil supplied from the oil pump 14 to the oil passage 16 is supplied directly to the rotation limit pin 36, while the lock pin 33 passes through the CTA 63. Supplied. Thereby, the coupling between the housing 22 and the rotor 23 by the rotation limit pin 36 and the lock pin 33 is released, and the cam phase is controlled by the VTC actuator 21 according to the operation state.

    As shown in FIG. 13, when the engine E was restarted, the hydraulic pressure supplied to the VTC actuator 21 increased relatively quickly with the increase in the engine rotation speed, and the hydraulic pressure supplied exceeded the release pressure (35 kPa). At that time, the rotation limiting pin 36 is detached from the rotation limiting groove 25b. However, at this time, the lock pin 33 is fitted in the lock hole 25a, and the housing 22 and the rotor 23 remain integrated at the coupling angle, so the engine E is operated with the start cam phase. When the hydraulic oil is filled in the CTA 63 after the engine E is started, the CTA hydraulic pressure supplied from the CTA 63 to the lock pin 33 rises. When the CTA hydraulic pressure exceeds the release pressure (50 kPa), the lock pin 33 is locked to the lock hole 25a. Thus, the housing 22 and the rotor 23 can rotate relative to each other within the maximum rotation range θ1.

<Restart after engine stall>
When the engine E stalls on a slope or the like, unlike the case where the engine E is normally stopped, the rate of decrease in the engine rotation speed until the engine E is stopped is large, and the cam phase of the intake camshaft 4 is also maximized from the most advanced angle. A range up to a retard angle can be taken. In this case, in this embodiment, the starting cam phase is established at the time of restart by the following procedure.

(Restart after stall 1)
Not much time has passed after the stall of the engine E, there is a sufficient amount of hydraulic oil in the CTA 63, and the cam phase is at the most retarded angle (position where the rotation limiting pin 36 cannot be fitted into the rotation limiting groove 25b). 14), the drive current is supplied to the linear solenoid 31 as soon as the engine E starts cranking, as shown in FIG. Then, the spool valve 30 moves to the advance position, and the CTA 63 operates to the advance side. As a result, an advance cam torque acts on the intake camshaft 4, and the second valve body 26b of the reed valve 26 opens each time the rotor 23 rotates relative to the housing 22 toward the advance side. The hydraulic oil in the chamber 47b flows into the advance side hydraulic chamber 47a and relatively rotates the third vane 43 (that is, the rotor 23) to the advance side. Further, when the retard side cam torque is applied, the first and second valve bodies 26a, 26b of the reed valve 26 are closed, and the cam phase is maintained without moving the hydraulic oil. Then, at the moment when the relative angle between the housing 22 and the rotor 23 becomes the coupling angle, the lock pin 33 urged by the lock pin spring 34 is fitted into the lock hole 25a, and the start cam phase of the intake camshaft 4 is Established and smooth restart is realized. At the moment when the lock pin 33 is inserted into the lock hole 25a, the rotation limit pin 36 is also inserted into the rotation limit groove 25b.

(Restart after stall 2)
When a certain amount of time elapses after the engine E is stalled, there is not a sufficient amount of hydraulic oil in the CTA 63, and the cam phase is at the most retarded angle side, the engine E is When cranking is started, the rotor 23 and the housing 22 are alternately rotated relative to each other between the advance side and the retard side by the cam torque received by the intake camshaft 4, and first, the rotation limiting pin 36 is in the rotation limiting groove 25b. The relative rotation is performed within the rotation limit range θ2. Next, at the moment when the relative angle between the housing 22 and the rotor 23 becomes the coupling angle, the lock pin 33 biased by the lock pin spring 34 is fitted into the lock hole 25a, and the cam phase at the start of the intake camshaft 4 Is established and smooth restart is realized.

(Restart after stall 3)
When a certain amount of time has passed after the stall of the engine E, there is no sufficient amount of hydraulic oil in the CTA 63, and the cam phase is within the rotation limit range θ2, the rotation limit pin 36 is connected to the rotation limit groove 25b. When the engine E starts cranking, the rotor 23 and the housing 22 are moved between the advance side and the retard side within the rotation limit range θ2 by the cam torque received by the intake camshaft 4 when the engine E starts cranking. At the moment when the relative rotation of the housing 22 and the rotor 23 becomes the coupling angle, the lock pin 33 urged by the lock pin spring 34 is fitted into the lock hole 25a, and the intake camshaft The starting cam phase of 4 is established and smooth restart is realized.

[Partial modification]
FIG. 16 is an enlarged cross-sectional view of a main part of a VTC actuator according to a partial modification.
Some of the modifications have substantially the same configuration as that of the above-described embodiment, but the installation form of the rotation limiting pin is different.

  As shown in FIG. 16, the rotation limit pin 36 of a partially modified example is held on the housing 22 side, and the VTC actuator is applied so that the centrifugal force accompanying the rotation of the intake camshaft 4 acts when the engine E is operated. It is installed so as to be substantially orthogonal to the axis 21 (that is, the axis of the intake camshaft 4). The rotor 23 is formed with a rotation restricting groove 23a into which the tip of the rotation restricting pin 36 is fitted, while the restricting pin spring 37 constantly biases the rotation restricting pin 36 toward the rotor 23. And if the front-end | tip of the rotation limitation pin 36 fits into the rotation limitation groove 23a, the relative rotation of the housing 22 and the rotor 23 will be performed within the rotation limitation range θ2. Note that the rotation restriction range θ2 of the partial modification is also set in the same manner as in the embodiment.

  In the case of a partial modification, during normal operation of the engine E, the rotation limiting pin 36 is moved to the outer peripheral side by centrifugal force, and the housing 22 and the rotor 23 are relatively rotated within the maximum rotation range θ1. In addition, when the engine E is stopped or cranked, the rotation speed of the engine decreases, so that the rotation limit pin 36 urged by the limit pin spring 37 is fitted into the rotation limit groove 23a, and the housing 22 and the rotor 23 are connected. Relative rotation occurs within the rotation limit range θ2. In some modified examples, by adopting such a configuration, an oil passage for supplying hydraulic oil to the rotation limiting pin 36 becomes unnecessary, and the structure of the VTC actuator 21 is simplified.

  Although the description of the specific embodiment is finished as described above, the present invention can be widely modified without being limited to the above-described embodiment and some modified examples. For example, although the above embodiment is an application of the present invention to an in-line four-cylinder DOHC gasoline engine, it is naturally applicable to a V-type engine, a diesel engine, or the like. In the above embodiment, the present invention is applied to an engine having a VTC only on the intake camshaft side, but may be applied to an engine having a VTC also on the exhaust camshaft side. In addition, the specific configurations of the engine and the valve mechanism including the VTC actuator can be changed as appropriate without departing from the gist of the present invention. In order to quickly and surely discharge hydraulic oil from the advance side hydraulic chamber, a hydraulic release valve may be installed on the OPA side.

It is a principal part perspective view of the engine for motor vehicles concerning an embodiment. It is a disassembled perspective view of the VTC actuator which concerns on embodiment. It is a schematic block diagram of the VTC actuator which concerns on embodiment. It is a principal part disassembled perspective view of the VTC actuator which concerns on embodiment. It is a principal part disassembled perspective view of the VTC actuator which concerns on embodiment. It is explanatory drawing which shows the relative rotation range of the housing and rotor which concern on embodiment. It is a schematic diagram which shows the advance angle operation state of the VTC actuator which concerns on embodiment. It is a schematic diagram which shows the retard angle operation state of the VTC actuator which concerns on embodiment. It is a schematic diagram which shows the holding | maintenance operation state of the VTC actuator which concerns on embodiment. It is a mimetic diagram showing the stop operation state of the VTC actuator concerning an embodiment. It is a graph which shows the operation state at the time of an engine stop of a lock pin and a rotation limiting pin. It is a schematic diagram which shows the operation state at the time of restart of the VTC actuator which concerns on embodiment. It is a graph which shows the operating state at the time of engine starting of a lock pin and a rotation limiting pin. It is a schematic diagram which shows the restart state after the stall of the VTC actuator which concerns on embodiment. It is a schematic diagram which shows the restart state after the stall of the VTC actuator which concerns on embodiment. It is explanatory drawing which shows the relative rotation range of the housing and rotor which concern on a partial modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder head 4 Intake camshaft 8 Intake cam sprocket 10 Crankshaft 14 Oil pump 16 Oil path 21 VTC actuator 22 Housing (1st rotation member)
23 Rotor (second rotating member)
30 Spool Valve 31 Linear Solenoid 32 Return Spring 33 Lock Pin 34 Lock Pin Spring 36 Rotation Limit Pin 37 Limit Pin Spring 61 First OPA
62 2nd OPA
63 CTA
E engine

Claims (5)

A first rotating member that rotates in synchronization with the crankshaft; a second rotating member that rotates integrally with the camshaft and that is rotatably coupled to the first rotating member; the first rotating member and the second rotating member; A variable cam phase internal combustion engine having a driving means for relatively rotating a rotating member within a predetermined first angle range;
Relative rotation limiting means for limiting relative rotation between the first rotating member and the second rotating member within a second angle range narrower than the first angle range;
A cam phase variable internal combustion engine comprising cam phase fixing means for coupling / integrating the first rotating member and the second rotating member with a predetermined coupling angle within the second angle range.   The cam phase variable internal combustion engine according to claim 1, wherein the coupling angle is set at one end of the second angle range. The relative rotation limiting means is formed on a stopper member held on one of the first rotating member and the second rotating member, and on the other of the first rotating member and the second rotating member. And a rotation limiting groove into which the stopper member is fitted,
The cam phase variable internal combustion engine according to claim 1 or 2, wherein an operating direction of the stopper member is substantially parallel to an axis of the camshaft. The relative rotation limiting means is formed on a stopper member held on one of the first rotating member and the second rotating member, and on the other of the first rotating member and the second rotating member. And a rotation limiting groove into which the stopper member is fitted,
3. The variable cam phase internal combustion engine according to claim 1, wherein an operating direction of the stopper member is substantially orthogonal to an axis of the camshaft.   The said stopper member is driven by at least one of the centrifugal force accompanying rotation of the said 1st rotation member or the said 2nd rotation member, and the hydraulic fluid supplied from the pressure oil supply means, The feature is characterized by the above-mentioned. 4. A cam phase variable internal combustion engine described in the item 4.

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