JP2011069287A - Valve opening/closing timing control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve opening/closing timing control device which effectively achieves retention at an intermediate phase without being affected by existence of foreign matter and the like, but does not easily fail due to a simple mechanism. <P>SOLUTION: This device includes: a driving side rotational member 1 synchronously rotatable with a crankshaft; a driven side rotational member 2 rotatable with a camshaft 3 as one body; a phase converting mechanism displacing a relative phase between the driving side rotational member 1 and the driven side rotational member 2 to an advanced angle phase side or a retarded angle phase side by supplying and discharging an operating fluid to each of two kinds of pressure chambers, the volume of which is complementarily varied by a movable partition 5; and biasing members S1, S2 biasing the relative phase toward a predetermined phase suitable for a start-up of an internal combustion engine except for a most advanced angle phase and a most retarded angle phase. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drive-side rotating member that rotates synchronously with a crankshaft of an internal combustion engine, and a camshaft that is arranged coaxially with respect to the drive-side rotating member and opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine. The working fluid is supplied to each of the two types of pressure chambers whose volumes can be complementarily varied by a movable partition with respect to the driven side rotating member that rotates integrally with the driven side rotating member and the relative phase between the driving side rotating member and the driven side rotating member. The present invention relates to a valve opening / closing timing control device having a phase conversion mechanism that is displaced by exhaust.

  As prior art document information related to this type of valve opening / closing timing control device, there is Patent Document 1 shown below. The valve opening / closing timing control device described in Patent Document 1 includes a lock mechanism capable of locking the relative phase to an intermediate phase suitable for starting the internal combustion engine as necessary. The lock mechanism includes a lock groove formed on the driven side rotation member, and a lock pin supported movably on the drive side rotation member so as to be engageable with the lock groove. It is biased by a spring in the direction of engaging with the groove. When the relative phase of both rotating members reaches an intermediate phase, the lock pin is configured to automatically enter the lock groove by the biasing force of the spring. After the start of the internal combustion engine is completed, generally, an operation of releasing the lock by the lock mechanism by the oil pressure supplied by an oil pump or the like and displacing from the intermediate phase to the advance side by the oil pressure is also performed.

  Further, in general, in the valve opening / closing timing control device, as a means for suppressing the tendency that the driven side rotating member tends to be delayed with respect to the driving side rotating member due to the cam reaction force received from the valve spring of the intake valve or the exhaust valve. In many cases, a biasing mechanism such as a torsion spring that biases the relative phase toward the intermediate phase is provided. In particular, the torsion spring of the valve opening / closing timing control device described in Patent Document 1 has an urging function limited between the intermediate restriction phase and the most retarded angle phase, which are located on the retarded phase direction side of the intermediate phase. Since the urging function does not work in the region between the advance angle phase and the intermediate phase, the displacement operation from the advance angle phase to the intermediate phase or the intermediate regulation phase is quickly performed by the cam reaction force and the oil pressure by the pump.

JP 2009-074384 (0009, paragraph 0029, FIG. 1, FIG. 2, FIG. 3)

  However, in the valve opening / closing timing control device described in Patent Document 1, the locking operation to the intermediate phase depends on the operation of entering the lock pin when the intermediate phase is reached, and therefore exists in, for example, oil. If the movement of the lock pin is hindered by a foreign object, the lock pin is not surely engaged with the lock groove, and there is a possibility that the lock to the intermediate phase is not sufficiently performed.

  In addition, after the start of the internal combustion engine in the intermediate phase, in order to escape from the intermediate phase in order to shift the relative phase to the advanced position, a mechanism such as supplying oil to push the lock pin out of the lock groove is used. Since it is necessary, the valve timing control device tends to be larger and complicated.

  Accordingly, an object of the present invention is to provide a valve opening / closing timing at which an intermediate phase can be effectively maintained without being affected by the presence of foreign matter, in view of the problems given by the conventional valve opening / closing timing control device exemplified above. It is to provide a control device. Another object of the present invention is to provide a valve opening / closing timing control device that is mechanically simpler, less likely to fail, and easy to downsize.

The first characteristic configuration of the valve opening / closing timing control device according to the present invention is:
A drive-side rotating member that rotates synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating member that is coaxially disposed with respect to the driving-side rotating member and rotates integrally with a camshaft that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine;
The relative phase between the driving side rotating member and the driven side rotating member is set to an advance phase phase or a retard angle phase depending on supply / discharge of working fluid to / from each of the two types of pressure chambers whose volumes are complementarily variable by a movable partition. A phase conversion mechanism to be displaced to the side,
And an urging member that urges the relative phase toward a predetermined phase suitable for starting the internal combustion engine excluding the most advanced angle phase and the most retarded angle phase.

  That is, the valve opening / closing timing control device according to the first characteristic configuration of the present invention does not include a lock mechanism formed by a lock groove formed on one rotating member and a lock pin supported on the other rotating member. Instead, it has a biasing member that biases the relative phase toward a predetermined phase (starting optimum phase) suitable for starting the internal combustion engine excluding the most advanced angle phase and the most retarded angle phase. Therefore, in a state where there is no force from the hydraulic oil, the relative phase is displaced to the optimum starting phase by the action of the biasing member. Therefore, since there is no problem that the movement of the lock pin is hindered by foreign matter in the oil, the urging member can always stably hold the start phase optimally.

In addition, the lock mechanism is not a lock groove formed on one rotating member and a lock pin supported on the other rotating member, but is attached between the driving side rotating member and the driven side rotating member. Since it is composed of a biasing member, a valve opening / closing timing control device that is mechanically simple and difficult to break down can be obtained, and the valve opening / closing timing control device can be easily downsized.
Further, since there is no lock mechanism using a lock pin that alternately engages and disengages from the lock groove, no noise is generated by the lock mechanism when the internal combustion engine is started.

In another aspect of the present invention, the biasing member includes a first biasing member that biases the relative phase in the advance phase direction and a second biasing member that biases the relative phase in the retard phase direction. And,
A first restricting portion that limits an urging force by the first urging member between the predetermined phase and the most retarded phase; and an urging force by the second urging member between the predetermined phase and the most advanced angle phase. It is in the point provided with the 2nd control part to restrict.

  The biasing member that biases the relative phase toward the predetermined phase in the region from the most advanced angle phase side to the most retarded angle phase side is, for example, one that biases the relative phase to the predetermined phase when no external force is applied. The torsion spring (biasing member) can also be used. However, in this configuration, since the urging force of the urging member becomes the weakest in the vicinity of the predetermined phase, it is difficult to stably hold the predetermined phase. In addition, since the restoring force of the urging member increases as it moves away from the predetermined phase toward the most advanced phase or the most retarded phase, a large hydraulic pressure is used to displace the relative phase against the urging force of the urging member. Is required, and energy loss tends to increase.

  However, as in this configuration, if two biasing members having opposite biasing directions are used, and the acting force from the two biasing members cooperates, the relative phase is biased to a predetermined phase. For example, as compared with the configuration in which the one torsion spring (biasing member) described above is provided, the phase can be stably maintained at a predetermined phase.

  Further, in this configuration, when the relative phase is operated from the predetermined phase to the retarded phase side or the advanced phase side by hydraulic operation or the like, for example, when operated to the retarded phase side, the second biasing member Since the urging force is limited between the predetermined phase and the most advanced angle phase by the second restricting portion, only the urging force of one of the urging members always acts, so that the urging force is displaced with a relatively small hydraulic pressure. be able to.

  Further, in this configuration, the urging force by the first urging member is limited between the predetermined phase and the most retarded angle phase by each restricting portion, and the urging force by the second urging member is between the predetermined phase and the most advanced angle phase. Therefore, in the state where there is no hydraulic pressure for displacing the relative phase, the predetermined phase is such that the biasing force toward the advance phase side from the predetermined phase by the first biasing member is the first restricting portion. This is realized in a state where the urging force to the retarded phase side from the predetermined phase by the second urging member is regulated by the second regulating unit. As a result, even if the two biasing forces are not equal due to errors in the manufacturing accuracy of the biasing member, the relative phase is controlled to the initial predetermined phase without shifting to the retarded phase side or the advanced phase side due to the same error. easy.

  Another feature of the present invention is that the urging member has an urging force that opposes a displacement force that acts on the driven-side rotating member based on a torque fluctuation of the camshaft.

  With this configuration, the biasing force of the biasing member tends to cancel the displacement force acting on the driven side rotation member based on the torque fluctuation of the camshaft, so that the relative phase is maintained at the predetermined phase by the biasing member. The accuracy is increased, and the relative phase control accuracy by hydraulic pressure is improved.

  Another characteristic configuration of the present invention is that the biasing member is a spring disposed between the driving side rotating member and the driven side rotating member.

  With this configuration, the present invention can be implemented by a biasing member having a simple configuration in which a spring such as a torsion spring or a spring spring is disposed between the driving side rotating member and the driven side rotating member that are arranged adjacent to each other. As a result, the assembly operation of the valve opening / closing timing control device is facilitated, and the miniaturization is facilitated.

A fifth characteristic configuration of the valve timing control device according to the present invention is as follows.
A drive-side rotating member that rotates synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating member that is coaxially disposed with respect to the driving-side rotating member and rotates integrally with a camshaft that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine;
A retarding chamber formed by the drive-side rotating member and the driven-side rotating member, and moving the relative phase of the driven-side rotating member with respect to the driving-side rotating member in the retarding direction by increasing the volume, and a volume An advance chamber that moves the relative phase in the advance direction by expanding
And an urging member that urges the relative phase toward a predetermined phase excluding the most advanced angle phase and the most retarded angle phase.

  That is, the valve timing control apparatus according to the fifth characteristic configuration of the present invention does not include a lock mechanism formed by a lock groove formed on one rotary member and a lock pin supported on the other rotary member. Instead, it has a biasing member that biases the relative phase toward a predetermined phase excluding the most advanced angle phase and the most retarded angle phase. Therefore, in a state where there is no force from the hydraulic oil, the relative phase is displaced to a predetermined phase by the action of the urging member. Accordingly, there is no problem that the movement of the lock pin is hindered by the foreign matter in the oil, so that the holding to the predetermined phase (for example, the optimum starting phase) is always stably realized by the biasing member.

According to another characteristic configuration of the present invention, the biasing member includes a first biasing member that biases the relative phase to a first predetermined phase located on the advance phase direction side of the most retarded phase and the relative phase. And a second biasing member that biases the second predetermined phase located on the retarded phase direction side of the most advanced phase,
The first biasing member biases the relative phase from the most retarded phase to the first predetermined phase and does not bias from the first predetermined phase to the most advanced angle phase,
The second biasing member is in a point that biases the relative phase from the most advanced angle phase to the second predetermined phase and does not bias from the second predetermined phase to the most retarded phase.

  The urging member that urges the relative phase toward the predetermined phase in the region from the most advanced angle phase side to the most retarded angle phase side can be configured by, for example, a single torsion spring. However, in this configuration, since the urging force of the urging member becomes the weakest in the vicinity of the predetermined phase, it is difficult to stably hold the predetermined phase. In addition, since the restoring force of the urging member increases as it moves away from the predetermined phase toward the most advanced phase or the most retarded phase, a large hydraulic pressure is used to displace the relative phase against the urging force of the urging member. Is required, and energy loss tends to increase.

  As in this configuration, if two biasing members having opposite biasing directions are used, and the acting force from the two biasing members cooperates to bias the relative phase to a predetermined phase, for example, Compared to the configuration in which the one torsion spring or the like is provided, the predetermined phase can be stably maintained.

  Further, in this configuration, when the relative phase is operated from the predetermined phase to the retarded phase side or the advanced phase side by hydraulic operation or the like, for example, when operated to the retarded phase side, the second biasing member Since the urging force is limited between the predetermined phase and the most advanced angle phase by the second restricting portion, only the urging force of one of the urging members always acts, so that the urging force is displaced with a relatively small hydraulic pressure. be able to.

  Further, in this configuration, when the hydraulic pressure for operating the relative phase is not operated, the first urging unit does not urge the predetermined phase from the first predetermined phase to the most advanced angle phase. The biasing member does not bias the predetermined phase from the second predetermined phase to the most retarded phase side. As a result, even if the two biasing forces are not equal due to errors in the manufacturing accuracy of the biasing member, the relative phase is controlled to the initial predetermined phase without shifting to the retarded phase side or the advanced phase side due to the same error. easy.

It is a fractured sectional view showing the whole composition of the valve timing control device by a 1st embodiment. It is the II-II sectional view of Drawing 1 in the predetermined phase state of a valve timing control device. It is IIIa-IIIa in the state of FIG. 2, IIIb-IIIb sectional drawing. It is the II-II sectional view of Drawing 1 in the most retarded angle phase of a valve timing control device. It is IIIa-IIIa and IIIb-IIIb sectional drawing in the state of FIG. It is the II-II sectional view of Drawing 1 in the most advance angle phase of a valve timing control device. It is IIIa-IIIa in the state of FIG. 6, IIIb-IIIb sectional drawing. It is a disassembled perspective view of the principal part of the valve timing control apparatus by 1st Embodiment. It is a figure corresponding to FIG. 3 of the valve timing control apparatus by 2nd Embodiment. It is a figure corresponding to FIG. 5 of the valve timing control apparatus by 2nd Embodiment. It is a figure corresponding to FIG. 7 of the valve timing control apparatus by 2nd Embodiment. It is a disassembled perspective view of the principal part of the valve timing control apparatus by 2nd Embodiment. It is a fractured sectional view of the whole composition of the valve timing control device by a 3rd embodiment. FIG. 14 is a cross-sectional view taken along lines XIVa-XIVa and XIVb-XIVb in FIG. 13 in a predetermined phase state. It is a disassembled perspective view of the principal part of the valve timing control apparatus by 4th Embodiment. It is an effect | action figure of the principal part of the valve timing control apparatus by 5th Embodiment.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated, referring drawings.
(First embodiment)
[Basic configuration]
As shown in FIG. 1, an external rotor 1 as a drive side rotating member that rotates synchronously with a crankshaft (not shown) of an engine (internal combustion engine), and an intake valve or an exhaust valve for opening and closing an engine combustion chamber A valve opening / closing timing control device is configured by including an internal rotor 2 as a driven side rotating member that rotates coaxially and integrally with the camshaft 3 and a fluid control valve mechanism V.

This valve opening / closing timing control device has a configuration in which an internal rotor 2 (driven side rotating member) is fitted into an external rotor 1 (driving side rotating member). As a result, the outer rotor 1 and the inner rotor 2 are rotatable relative to each other within a predetermined relative rotation phase with the rotation axis X as the center. A fluid pressure chamber is formed between the outer rotor 1 and the inner rotor 2, and as shown in FIG. 2, this fluid pressure chamber is retarded by a vane 5 as a partition supported on the outer periphery of the inner rotor 2. 11 and the advance chamber 12 are partitioned.
The vane 5 is inserted into a vane groove formed on the outer periphery of the inner rotor 2 and is urged in a protruding direction by a leaf spring or the like. Thus, regardless of the relative phase between the outer rotor 1 and the inner rotor 2, the outer end of the vane 5 is always held in sliding contact with the inner surface of the outer rotor in the fluid pressure chamber.

  The above-described camshaft 3 is disposed coaxially with the rotary shaft X and this camshaft 3 is connected to the internal rotor 2 by a connecting bolt 4. A front plate 6 is disposed on one surface of the external rotor 1, and a rear plate 7 is disposed on the other surface of the external rotor 1, and these are fixed to the external rotor 1 by a plurality of fixing bolts 8. The internal rotor 2 is disposed between the front plate 6 and the rear plate 7.

  A timing sprocket 7 </ b> S is integrally formed on the outer periphery of the rear plate 7. A power transmission member (not shown) such as a timing chain or a timing belt is installed between the timing sprocket 7S and a gear attached to the crankshaft of the engine.

  With this configuration, when the engine is in operation, the rotational driving force of the crankshaft is transmitted to the timing sprocket 7S via the power transmission member, and the external rotor 1 is rotationally driven in the rotational direction T shown in FIG. In conjunction with this rotation, the internal rotor 2 rotates in the same direction as the rotation direction T, whereby the camshaft 3 rotates, and the drive valve of a cam (not shown) provided on the camshaft 3 rotates the intake valve or the engine. The exhaust valve is opened and closed.

When hydraulic oil is supplied to the advance chamber 12 during operation of the engine, the volume of the advance chamber 12 expands due to the pressure acting on the vanes 5, so that the internal rotor 2 moves in the direction of the arrow T <b> 1 with respect to the external rotor 1. . As a result, the relative rotational phase between the outer rotor 1 and the inner rotor 2 moves in the advance direction.
On the contrary, when the hydraulic oil is supplied to the retarding chamber 11, the volume of the retarding chamber 11 is expanded by the pressure acting on the vane 5 in the opposite direction. Move to T2. As a result, the relative rotational phase between the outer rotor 1 and the inner rotor 2 moves in the retard direction. In this way, the opening / closing timing of the intake valve or the exhaust valve is controlled by changing the rotation phase of the camshaft 3 with respect to the rotation phase of the crankshaft.

  Engine oil is used as the hydraulic oil, and the valve timing control apparatus determines the relative rotational phase between the external rotor 1 and the internal rotor 2 as the optimum starting phase (also called intermediate phase) suitable for starting the engine. , An example of a predetermined phase) is provided. The holding mechanism M holds the outer rotor 1 and the inner rotor 2 at a set relative rotational phase in a situation where the pressure of the hydraulic oil immediately after the engine is started is very low, so that the camshaft 3 with respect to the rotational phase of the crankshaft. The engine rotation phase is maintained at the optimum starting phase, and the engine starts stably.

A general holding mechanism in a conventional valve opening / closing timing control device includes a lock groove formed in an internal rotor, and a lock pin supported by an external rotor so as to be able to move in and out of the lock groove. ing.
However, the holding mechanism M according to the present invention has two mainspring springs S1 and S2 (which apply urging forces in opposite directions to each other between the outer rotor 1 (driving side rotating member) and the inner rotor 2 (driven side rotating member). A spiral spring). The first spring S1 biases the relative phase toward the advance side, and the second spring S2 biases the relative phase toward the retard side. The two springs S1, S2 are accommodated in a recess 6a provided in the front plate 6, and a disc-like spacer 15 is interposed between the springs S1, S2. The recess 6a is covered with a disc-shaped cover 9. Details of the operation of the springs S1 and S2 will be described later.

  As shown in FIGS. 1 and 2, the internal rotor 2 includes a retard chamber side oil passage 11 a that supplies and discharges hydraulic oil to and from the plurality of retard chambers 11, and a supply and exhaust of operation to the plurality of advance chambers 12. The advance angle chamber side oil passage 12a is formed penetratingly. Since no lock pin is provided as a holding mechanism, an unlocking oil passage or the like for extruding the lock pin from the lock groove is not formed.

As shown in FIGS. 1 and 2, a bush 18 that is externally fitted to the camshaft 3 so as to be rotatable relative to the camshaft 3 is provided. From the supply oil passage 18 a of the bush 18 to the internal oil passage 3 a of the camshaft 3 and the internal rotor 2. An oil passage system for sequentially supplying hydraulic oil to the internal oil passage 2a is formed. The hydraulic fluid supplied from the hydraulic pump P to the supply oil passage 18a is supplied to the cylindrical space 2S of the internal rotor 2 by this oil passage system.
In addition, the hydraulic oil supplied to the cylindrical space 2S passes through the fluid control valve mechanism V supported so as to be rotatable relative to the outer rotor 1 and the inner rotor 2, and the above-described retarded chamber side oil passage 11a and It is supplied to the advance chamber side oil passage 12a and is discharged from the retard chamber side oil passage 11a and the advance chamber side oil passage 12a.

[Fluid control valve mechanism]
As shown in FIG. 1, the fluid control valve mechanism V integrally includes a hydraulic oil control unit Va having a spool valve 22 and a cylindrical hydraulic oil supply / discharge unit Vb so as to supply and discharge hydraulic oil. A housing 28 is provided. The spool valve 22 is slid up and down in the figure by an electromagnetic solenoid 21 disposed at the upper end of the hydraulic oil control unit Va. The hydraulic oil supply / discharge portion Vb is rotatably inserted into the cylindrical space 2S of the internal rotor 2.

A main oil passage 23 that receives the hydraulic oil from the internal oil passage 2a is formed in the center of the hydraulic oil supply / discharge portion Vb, and a check valve that prevents the flow of fluid toward the cylindrical space 2S in the inside thereof. C is provided. The spool valve 22 has a bottomed cylindrical shape.
The housing 28 is fixed to an engine front cover or the like, and the internal rotor 2 is rotatably supported via a hydraulic oil supply / discharge portion Vb.

  On the outer periphery of the hydraulic oil supply / discharge portion Vb, two ports 24 and 25, which are controlled to supply and discharge hydraulic oil by the spool valve 22, are formed as annular grooves. On the outer periphery of the hydraulic oil supply / discharge part Vb, an oil seal 27 is installed so as to prevent leakage of hydraulic oil from the first port 24 and the second port 25. The first port 24 is always in communication with the retard chamber communication hole 11a, and the second port 25 is always in communication with the advance chamber communication hole 12a.

  A compression spring 29 is installed between the spool valve 22 and the bottom surface of the housing 28 to urge the spool valve 22 upward in the figure. When the solenoid 21 is energized in the state of FIG. 1, the operation rod 30 protruding downward from the solenoid 21 moves the spool valve 22 to the lower position. When the energization is stopped, the operation rod 30 is retracted toward the solenoid 21, and the spool valve 22 returns to the upper position shown in FIG. 1 following the movement of the rod 22 by the urging force of the compression spring 29.

On the outer peripheral surface of the spool valve 22, annular discharge grooves 22a and 22b and a supply groove 22c are formed. The discharge grooves 22a and 22b are respectively provided with through holes 23a and 23b penetrating through the hollow portions inside.
As shown in FIG. 1, when the solenoid 21 is not energized, the positional relationship between the discharge grooves 22a and 22b and the supply groove 22c is such that the supply groove 22c communicates with the main oil passage 23 and the advance chamber communication hole 12a. The groove 22b is set so as to communicate with the retard side flow path 11a. When the solenoid 21 is energized, the supply groove 22c communicates with the main oil passage 23 and the retard side flow path 11a, and the discharge groove 22a communicates with the advance side flow path 12a.

  In this valve opening / closing timing control device, gaps are formed between the inner rotor 2 and the front plate 6 and between the inner rotor 2 and the rear plate 7 so that the hydraulic oil slightly leaks. The hydraulic oil slightly leaks even through the movable part. The leaked hydraulic oil is collected by the oil pan 36.

(Operation of valve timing control device)
As shown in FIG. 1, when the relative rotational phase is displaced in the advance direction T1, the solenoid 21 is deenergized while the hydraulic pump P is being driven. Then, the spool valve 22 is disposed at an upper position near the solenoid 21 together with the rod 30 of the solenoid 21 by the urging force of the compression spring 29. As shown in FIG. 1, the hydraulic oil supplied from the fluid pump P to the main oil passage 23 of the camshaft 8 has a cylindrical space 2S, a main oil passage 23, a supply groove 22c, an advance side passage 12a, a second It is pumped to each advance chamber 12 via the port 25. By this pumping, the vane 5 moves in the advance direction T1, and the hydraulic oil in each retard chamber 11 is discharged. The hydraulic oil discharged from the retard chamber 11 is discharged to the oil pan 36 through the first port 24, the retard side channel 11 a, the discharge groove 22 b, and the drain channel 32.

  On the other hand, when the relative rotational phase is displaced in the retard direction T2, the solenoid 21 is energized while the hydraulic pump P is being driven. Then, the spool valve 22 is pushed by the rod 22 of the solenoid 21 and arranged at the lower position. The hydraulic oil supplied from the fluid pump P to the main oil passage 23 of the camshaft 8 passes through the cylindrical space 2S, the main oil passage 23, the supply groove 22c, the retard side flow passage 11a, and the first port 24, and then is It is pumped to the corner chamber 11. By this pressure feeding, the vane 5 moves in the retarding direction T2, and the hydraulic oil in each advance chamber 12 is discharged. The hydraulic oil discharged from the advance chamber 12 is discharged to the oil pan 36 through the second port 25, the advance side flow path 12a, the discharge groove 22a, and the drain flow path 32.

[Outline of control system]
Although not shown in the drawings, the control system of the valve timing control device includes a crank angle sensor that detects the rotation angle of the crankshaft of the engine, a camshaft angle sensor that detects the rotation angle of the camshaft 3, and a fluid control. ECU (not shown) which controls the valve mechanism V is provided.
The ECU is formed with a signal system for acquiring information such as ignition key ON / OFF information, information from an oil temperature sensor that detects the oil temperature of the engine oil, and the like in the nonvolatile memory according to the operating state of the engine. The control information of the optimal relative rotational phase is stored.

  Then, the ECU detects the relative phase between the external rotor 1 and the internal rotor 2 from the detection results of the crank angle sensor and the camshaft angle sensor described above. Then, based on the information on the relative phase and the information on the operation state (engine speed, cooling water temperature, etc.), the fluid control valve mechanism V is operated to supply the hydraulic oil to the retard chamber 11 and the advance chamber 12. Supply and discharge are performed, and the relative rotation phase between the outer rotor 1 and the inner rotor 2 is controlled. This realizes phase control between the most retarded phase (relative rotational phase where the volume of the retarded chamber 11 is maximized) and the most advanced phase (relative rotational phase where the volume of the advanced chamber 12 is maximized). To do.

  When the operation for stopping the engine is performed, the ECU stops the supply and discharge of the hydraulic oil to and from the retard chamber 11 and the advance chamber 12 by the fluid control valve mechanism V, and the hydraulic pressure in any direction acts on the vane 5. As a result, the relative phase between the external rotor 1 and the internal rotor 2 is shifted to the optimal start phase suitable for the next start by the urging action of the springs S1 and S2 described above. Stop. When the engine is started after this stop, the engine is stably started.

  The springs S1 and S2 described above cooperate with each other to react to the outer rotor 1 from the valve springs of the intake valve and the exhaust valve when the inner rotor 2 is in a region retarded from the optimum start phase. In order to resist the force, the internal rotor 2 has a function of applying a biasing force in the direction of the optimum starting phase. Specifically, the spring spring S1 biasing force for biasing the relative phase toward the advance side is set higher than the spring spring S2 biasing toward the retard side. Accordingly, the relative phase of the internal rotor 2 that rotates integrally with the camshaft 3 tends to be delayed with respect to the rotation of the external rotor 1 due to the reaction force received from the valve springs of the intake valve and the exhaust valve, and the retardation chamber. When hydraulic oil is discharged from 11 and the advance chamber 12, the tendency to be held on the retard side from the optimum start phase is suppressed.

After the engine is started, the ECU changes the relative phase between the external rotor 1 and the internal rotor 2 by supplying and discharging hydraulic oil to and from the retard chamber 11 and the advance chamber 12 by the fluid control valve mechanism V. The opening / closing timing of the intake valve and the exhaust valve is controlled by.
When the engine stops due to an excessive load acting on the engine, the internal rotor 2 may reach the most retarded angle phase with respect to the external rotor 1. When the engine is started in such a situation, the ECU performs control to move the phase of the internal rotor with respect to the external rotor 1 to the optimal start phase at an early stage in order to start the engine stably.

  As a specific control form, the fluid control valve mechanism V discharges the hydraulic oil in the retard chamber 11 and supplies the hydraulic oil to the advance chamber 12 by controlling the ECU, whereby the fluid control valve mechanism V is internal to the external rotor 1. The rotor 2 is moved in the direction of the optimum starting phase. The rotational phase in which the internal rotor 2 is located on the most retarded side among the most retarded phase is referred to as the most retarded phase.

  However, according to the above control, when the engine is started in a state where the internal rotor 2 is in the most retarded phase, it takes time until the relative rotational phase reaches the optimum start phase, and the engine starts smoothly. Not done. In particular, since the temperature of the engine oil is low when the engine is stopped in a cold region, the viscosity of the hydraulic oil is high, and the hydraulic oil is not smoothly supplied to and discharged from the retard chamber 11 and the advance chamber 12. Not smoothly. In order to improve such an inconvenience, the difference between the strengths of the springs S1 and S2 described above assists the relative movement of the outer rotor 1 and the inner rotor 2 in the optimum starting phase direction and shortens the time required to reach the optimum starting phase. I am trying.

[Spring spring]
As shown in FIGS. 3 to 8, the first main spring S <b> 1 causes the rotational phase of the inner rotor 2 relative to the outer rotor 1 to be in the direction of the optimum starting phase in the retarded region A from the most retarded phase to the optimum starting phase. It works to energize. Conversely, the second spring spring S2 functions to bias the rotational phase of the internal rotor 2 with respect to the external rotor 1 in the direction of the optimum starting phase in the advance angle region B from the most advanced angle phase to the optimum starting phase.
As shown in FIG. 8, these springs S1 and S2 are formed by spirally forming a belt-shaped spring material, and therefore have a thickness (in the direction of the rotation axis X) compared to that having a coil portion such as a torsion spring. 1), even when two springs S1 and S2 are provided as shown in FIG. 1, a large space is not required in the direction of the rotation axis X, and the valve opening / closing timing control device can be downsized.

As shown in FIG. 3, each of the springs S <b> 1 and S <b> 2 includes a spiral spring body 30, and an inner engagement portion 31 that engages with the inner rotor 2 is radially inward at an inner diameter end thereof. An outer engagement portion 32 fixed to the outer rotor 1 is formed radially outwardly by bending at an outer diameter side end portion formed by bending.
An engagement recess 10G that can lock the inner engagement portion 31 is formed at one location on the outer periphery of the shaft-shaped portion 10 of the inner rotor 2 so as to correspond to the shape of the springs S1 and S2. . On the other hand, an engagement recess 6T capable of locking the outer engagement portion 32 is formed at one place on the inner surface of the front plate 6 connected to the external rotor 1.

  When setting the springs S1 and S2, first, the outer engagement portion 32 is locked and fixed to the engagement recess 6T of the outer rotor 1, and then resists the urging force of the springs S1 and S2 trying to return to the linear shape. In other words, after the inner engagement portion 31 is rotated a predetermined number of times in the direction in which the spring body 30 is wound around the axis X in the inner diameter direction, the inner engagement portion 31 is locked and fixed to the engagement recess 10G. To do. The rotational operation direction of the inner engagement portion 31 when performing the above setting is counterclockwise in the first mainspring S1 and clockwise in the second mainspring S2 in FIG.

By setting in the above manner, both ends of the springs S1, S2 are securely fixed to the outer rotor 1 and the inner rotor 2 so as not to move relative to each other, and the inner engagement portion 31 of the first spring S1 is fixed to the inner rotor. 2 is urged toward the advance side (clockwise in FIG. 2), and the inner engagement portion 31 of the second spring spring S2 urges the inner rotor 2 toward the retard side (counterclockwise in FIG. 2). Is done.
Only one of the two springs S1, S2 may be disposed in the recess 6a provided in the front plate 6, and the other may be disposed in the recess formed in the rear plate 7. In this case, The spacer 15 becomes unnecessary.

(Operation control)
As described above, when the engine is started normally, the supply and discharge of the hydraulic oil to and from the retard chamber 11 and the advance chamber 12 are stopped. Therefore, as shown in FIGS. 2 and 3, the springs S1 and S2 are energized. As a result, the relative phase between the outer rotor 1 and the inner rotor 2 is maintained at the optimum starting phase between the most retarded angle phase and the most advanced angle phase. Therefore, the engine can be started stably. When engine start is commanded by turning on the ignition key, cranking is performed by the cell motor, the engine is started, the hydraulic pump P is rotated, and hydraulic oil is supplied to the retard chamber 11 and the advance chamber 12. Is possible.

  In general, after the engine is started, hydraulic fluid is supplied to the retarded angle chamber 11 by the fluid control valve mechanism V under the control of the ECU, so that the relative rotational phase is shifted to the intermediate restriction phase slightly behind the optimum start phase. Let The intermediate regulation phase is a phase suitable for improving emissions and increasing torque at a low temperature, and is generally kept at the same phase during warm-up operation. 4 and 5 show the state of the most retarded phase exceeding the intermediate regulation phase.

  The displacement operation from the optimum starting phase to the retarding phase side such as the intermediate restriction phase by supplying hydraulic oil to the retarding chamber 11 is accompanied by the counterclockwise relative rotation operation of the internal rotor 2 in FIGS. 4 and 5. This is performed against the biasing force of the first mainspring S1, that is, with further drawing of the first mainspring S1. On the other hand, since the second main spring S2 is set in a sufficiently narrowed state, the displacement from the optimum starting phase to the retarded phase is merely relaxed compared to the optimum starting phase. The biasing force that substantially moves the relative rotational phase in the advance direction is not exhibited. After the warm-up operation period, the ECU shifts to normal operation control.

  On the other hand, in the normal operation control, when the displacement operation is performed on the advance side from the optimum starting phase, the relative rotation operation of the inner rotor 2 in the clockwise direction in FIGS. 6 and 7 is accompanied by the rotation of the second spring S2. This is performed against the force, that is, with the drawing of the second spring spring S2. On the other hand, since the first main spring S2 is set in a sufficiently narrowed state, the displacement from the optimum starting phase to the advance side is merely relaxed compared to the optimum starting phase. The biasing force that substantially moves the relative rotational phase in the retarded direction is not exhibited. 6 and 7 show the state of the most advanced angle phase.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.
In the second embodiment, as in the first embodiment, the holding mechanisms M that hold the relative rotational phase between the outer rotor 1 and the inner rotor 2 at the optimum starting phase suitable for starting the engine are opposite to each other. Two springs S1 and S2 are provided to exert the biasing force in the direction.

  As shown in FIGS. 9 to 12, the first feature of the configuration of the second embodiment is that the circumferential width of the engaging recess 10G of the inner rotor 2 is the same as that of the inner engaging portion 31 of the spring springs S1 and S2. The point is that it is sufficiently larger than the thickness. With this configuration, each inner engagement portion 31 locked to the engagement recess 10G is movable along the circumferential direction in the engagement recess 10G.

  The second structural feature of the second embodiment is that the front plate 6 is provided with a first restriction piece 33A that can come into contact with the inner engagement portion 31 of the first spring spring S1, and similarly, the second spring spring. The second restriction piece 33B that can contact the inner engagement portion 31 of S2 is erected. The first restricting piece 33A restricts the displacement of the inner engagement portion 31 of the first mainspring spring S1 in the direction of the advance angle region B, and the second restricting piece 33B is the delay of the inner engagement portion 31 of the second mainspring spring S2. The displacement in the direction of the corner area A is restricted.

  As a result, as shown in FIG. 10A, the first main spring S1 has a first predetermined phase (starting) in which the first regulating piece 33A defines the rotational phase of the inner rotor 2 relative to the outer rotor 1 from the most retarded phase. It works to urge in the direction of the optimum starting phase in the retarded region A (corresponding to the optimum phase). On the contrary, as shown in FIG. 11B, the second spring spring S2 has a second predetermined phase (starting) in which the first regulating piece 33B defines the rotational phase of the inner rotor 2 relative to the outer rotor 1 from the most advanced angle phase. Energizes in the direction of the optimum starting phase in the advance angle region B (corresponding to the optimum phase).

  As shown in FIG. 10B, in the retarded angle region A from the most retarded phase to the optimum starting phase, the inner engaging portion 31 of the second spring S2 is locked by the second restricting piece 33B. It can no longer act on the inner rotor 2 by relatively moving in the advance direction within the wide engaging recess 10G. Therefore, only the urging force of the first spring S1 acts on the rotational phase, and the urging force does not act on the rotational phase from the second spring S2.

  Conversely, as shown in FIG. 11A, in the advance angle region B from the most advanced angle phase to the optimum starting phase, the inner engagement portion 31 of the first spring S1 is locked by the first restricting piece 33A. As a result, it can no longer act on the inner rotor 2 by relatively moving in the retarding direction within the wide engaging recess 10G. For this reason, only the urging force of the second spring spring S2 acts on the rotational phase, and no urging force acts on the rotational phase from the first spring spring S1.

  As a result, the urging operation positions of the main springs S1, S2 with respect to the inner rotor 2 by the inner engaging portions 31 are limited to the positions of the first and second restricting pieces 33A, 33B. When the supply and discharge of the hydraulic oil to and from the corner chamber 12 is stopped, as shown in FIG. 9, even when the balance of the urging forces of the mainsprings S1 and S2 collapses from the initial state due to long-term use, the rotational phase However, it is possible to accurately maintain the optimum starting phase without shifting due to the loss of balance.

(Third embodiment)
As illustrated in FIGS. 13 and 14, the third embodiment can be said to use two torsion springs S <b> 1 and S <b> 2 instead of the mainspring as an urging member that maintains the relative phase at the optimum starting phase. Here, the first torsion spring S1 that biases the relative phase toward the advance side is housed in the recess 6a of the front plate 6, whereas the second torsion spring S2 that biases toward the retard side is the rear plate. 7 is housed in the recess 7a.

FIG. 14 shows the states of the torsion springs S1 and S2 in the optimum starting phase.
The outer end portions 32 of the torsion springs S1 and S2 are locked to the engaging recesses 6T on the inner surface of the front plate 6 connected to the outer rotor 1 so as not to be relatively movable. However, the inner end portions 31 of the torsion springs S1 and S2 are engaged with a wide engagement recess 10G cut out sufficiently longer than the outer diameter of the inner end portion 31 so as to be relatively movable.
And from the bottom part of the front plate 6, the regulation pieces 33A and 33B which can be engaged with the inner end part 31 of the torsion springs S1 and S2 are erected.
The following effects are achieved by the wide engaging recess 10G and the restricting pieces 33A and 33B as in the second embodiment.

As understood from FIG. 14A, in the advance angle region B from the most advanced angle phase to the optimum starting phase, the inner engagement portion 31 of the first torsion spring S1 is locked by the first restricting piece 33A. Therefore, it does not act on the inner rotor 2. Therefore, only the urging force of the second torsion spring S2 acts on the rotational phase, and no urging force acts on the rotational phase from the first torsion spring S1.
On the contrary, as understood from FIG. 14B, in the retardation region A from the most retarded phase to the optimum starting phase, the inner engagement portion 31 of the second torsion spring S2 is engaged by the second regulating piece 33B. Since it is stopped, it does not act on the inner rotor 2. Therefore, only the urging force of the first mainspring spring S1 acts on the rotational phase, and no urging force acts on the rotational phase from the second torsion spring S2.

  As a result, the biasing operation positions of the inner engagement portions 31 of the torsion springs S1 and S2 with respect to the inner rotor 2 are limited to the positions of the first and second restricting pieces 33A and 33B. When the supply and discharge of the hydraulic oil to and from the advance chamber 12 is stopped, even if the balance of the urging forces of the torsion springs S1 and S2 is lost from the initial state due to long-term use, the rotational phase is lost. Therefore, it is possible to accurately maintain the optimum starting phase without shifting. The position of the first restriction piece 33A corresponds to a first predetermined phase, and the position of the second restriction piece 33B corresponds to a second predetermined phase.

(Fourth embodiment)
In the fourth embodiment, as shown in FIG. 15, as an urging member that keeps the relative phase at the optimum starting phase, the inner engagement portion 31 locked to the engagement recess 10 </ b> G of the inner rotor 2 and the outer rotor 1. One torsion spring S having an outer engaging portion 32 locked to the engaging recess 6T is used.
In this embodiment, when the supply and discharge of the hydraulic oil to and from the retard chamber 11 and the advance chamber 12 are stopped, the relative phase is displaced to the optimum start phase by the urging force of the torsion spring S, and the same phase is maintained. In the displacement operation from the optimum starting phase to the retard side by the hydraulic oil, the inner engagement portion 31 of the torsion spring S is rotated relative to the outer engagement portion 32 in the counterclockwise direction when viewed from above in FIG. Therefore, the torsion spring S is deformed with a reduced diameter. Conversely, in the displacement operation from the optimum starting phase to the advance side, the inner engagement portion 31 of the torsion spring S is rotated relative to the outer engagement portion 32 in the clockwise direction when viewed from above in FIG. Thus, the torsion spring S is performed with a deformation that expands the diameter.

(Fifth embodiment)
In the fifth embodiment, the engagement concave portion 10 of the inner rotor 2 is formed to be very long in the circumferential direction, and the cylindrical hydraulic oil supply / discharge portion Vb is used as an urging member that maintains the relative phase at the optimum starting phase. One externally fitted torsion spring S is used. Both ends 31a, 31b of the torsion spring S are extended outward in the radial direction, and both ends 31a, 31b are engaged with the engaging recess 10 in a state where they are brought close to each other against the urging force of the torsion spring S. I am allowed to enter.
The front plate 6 is provided with a pair of restricting pieces 34A and 34B that are in contact with or adjacent to the outside of the torsion spring S in the vicinity of both ends 31a and 31b. In a state where the supply and discharge of the hydraulic oil to the retard chamber 11 and the advance chamber 12 are stopped, both ends 31a and 31b of the torsion spring S are connected to both ends 10a and 10b of the engaging recess 10 as shown in FIG. And the pair of restricting pieces 34A and 34B are simultaneously pressed to bias the relative phase to the optimum starting phase.
When the relative phase is displaced to the retard side by the action of the hydraulic oil, as shown in FIG. 16B, the end 31b of the torsion spring S is pressed against the restricting piece 34B and the engagement of the inner rotor 2 is performed. The displacement operation is executed while one end face 10a of the combined recess 10G pushes the other end 31a of the torsion spring S counterclockwise.

  The present invention can be used for all valve opening / closing timing control devices for setting the opening / closing timing of at least one of an intake valve and an exhaust valve of an engine.

1 External rotor (drive side rotating member)
2 Internal rotor (driven side rotating member)
2S Cylindrical space 3 Camshaft 5 Vane (partition)
6 Front plate 6T Engaging recess 7 Rear plate 10 Shaft 10G Engaging recess 11 Retarding chamber 11a Retarding chamber side oil passage 12 Advance chamber 12a Advance chamber side oil passage 22 Spool valve 24 First port 25 Second Port 28 Housing 33A First restriction piece 33B Second restriction piece M Holding mechanism P Hydraulic pump S1 First spring (spring)
S2 Second spring (spring)
T1 Advance angle direction T2 Delay angle direction V Fluid control valve mechanism Va Hydraulic oil control part Vb Hydraulic oil supply / discharge part

Claims (6)

A drive-side rotating member that rotates synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating member that is coaxially disposed with respect to the driving-side rotating member and rotates integrally with a camshaft that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine;
The relative phase between the driving side rotating member and the driven side rotating member is set to an advance phase phase or a retard angle phase depending on supply / discharge of working fluid to / from each of the two types of pressure chambers whose volumes are complementarily variable by a movable partition. A phase conversion mechanism to be displaced to the side,
And a biasing member that biases the relative phase toward a predetermined phase suitable for starting the internal combustion engine excluding the most advanced angle phase and the most retarded angle phase. The urging member includes a first urging member that urges the relative phase in the advance angle phase direction and a second urging member that urges the relative phase in the retard angle phase direction, and
A first restricting portion that limits an urging force by the first urging member between the predetermined phase and the most retarded phase; and an urging force by the second urging member between the predetermined phase and the most advanced angle phase. The valve opening / closing timing control device according to claim 1, further comprising a second restricting portion to be limited. 3. The valve opening / closing timing control device according to claim 1, wherein the urging member has a urging force that opposes a displacement force that acts on the driven side rotation member based on a torque fluctuation of the camshaft. 4. The valve opening / closing timing control device according to any one of claims 1 to 3, wherein the biasing member is a spring disposed between the driving side rotating member and the driven side rotating member. A drive-side rotating member that rotates synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating member that is coaxially disposed with respect to the driving-side rotating member and rotates integrally with a camshaft that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine;
A retarding chamber formed by the drive-side rotating member and the driven-side rotating member, and moving the relative phase of the driven-side rotating member with respect to the driving-side rotating member in the retarding direction by increasing the volume, and a volume An advance chamber that moves the relative phase in the advance direction by expanding
And a biasing member that biases the relative phase toward a predetermined phase excluding the most advanced angle phase and the most retarded angle phase. The urging member includes a first urging member that urges the relative phase to a first predetermined phase that is positioned on the advance phase direction side of the most retarded phase, and the relative phase that is retarded from the most advanced angle phase. A second biasing member that biases to a second predetermined phase located on the phase direction side,
The first biasing member biases the relative phase from the most retarded phase to the first predetermined phase and does not bias from the first predetermined phase to the most advanced angle phase,
6. The valve opening / closing according to claim 5, wherein the second biasing member biases the relative phase from the most advanced angle phase to the second predetermined phase and does not bias from the second predetermined phase to the most retarded phase. Timing control device.

Images