JP4026286B2 - Valve timing control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a valve opening / closing timing control device (valve timing adjusting device for an internal combustion engine) used for controlling the opening / closing timing of an intake valve or an exhaust valve in a valve operating device of an internal combustion engine.
[0002]
[Prior art]
As one of such valve opening / closing timing control devices, driving force is transmitted from a drive shaft (crankshaft) of an internal combustion engine to a driven shaft (camshaft) that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine. A housing member provided in a driving force transmission system that rotates integrally with a driving shaft (or driven shaft) and a pair of shoe portions provided on the housing member are assembled so as to be relatively rotatable at a hub portion. The rotor member that forms the advance oil chamber and the retard oil chamber in the housing member at the portion and rotates integrally with the driven shaft (or drive shaft), the housing member and the rotor at the initial phase of the housing member and the rotor member In addition to a lock mechanism that regulates relative rotation of members, it also has a hydraulic circuit that controls the supply and discharge of hydraulic oil to and from the advance oil chamber and retard oil chamber, and also controls the locking and unlocking of the lock mechanism. There are those with, for example, shown in Japanese Patent Laid-Open No. 9-60508.
[0003]
In the valve opening / closing timing control device of this publication, as a locking mechanism, it is assembled in a housing hole provided in the vane portion of the rotor member so as to be slidable in the axial direction of the camshaft, and the tip portion is formed in a tapered shape. A lock pin, a taper hole that is provided in the housing member and can be taper-fitted at the tip of the lock pin in the initial phase of the housing member and the rotor member, and a spring that biases the lock pin toward the taper hole. The lock mechanism is adopted, and the tip of the lock pin is taper-fitted into the taper hole at the initial phase of the housing member and the rotor member, so that the relative rotation of the housing member and the rotor member is restricted, and the tip of the lock pin The housing member and the rotor member are allowed to rotate relative to each other with the portion retracted from the tapered hole.
[0004]
[Problems to be solved by the invention]
However, in the valve opening / closing timing control device disclosed in the above publication, since the lock pin is disposed in the vane portion, the vane portion in which the lock pin is disposed has a circumference as compared with the vane portion in which the lock pin is not disposed. It must be formed thick in the direction. For this reason, not only is the variable control region of the valve opening / closing timing limited by the phase conversion angle, but the number of vanes is also limited, which contributes to improving the responsiveness of the valve opening / closing timing control device. There was a problem.
[0005]
Therefore, an object of the present invention is to prevent the phase conversion angle and the number of vane portions from being restricted by the lock mechanism in the valve opening / closing timing control device.
[0006]
[Means for Solving the Problems]
The technical means taken to solve the above problems is provided in a driving force transmission system that transmits a driving force from a driving shaft of an internal combustion engine to a driven shaft that opens and closes at least one of an intake valve and an exhaust valve. Alternatively, a housing member that rotates integrally with the driven shaft and a pair of shoe portions provided on the housing member are assembled so as to be rotatable relative to each other. A rotor member that forms a chamber and rotates integrally with the driven shaft or the drive shaft, and a lock mechanism that restricts relative rotation of the housing member and the rotor member at an initial phase of the housing member and the rotor member; A hydraulic circuit that controls supply and discharge of hydraulic oil to and from the advance oil chamber and the retard oil chamber, and controls locking and unlocking of the lock mechanism, and the housing member includes the low pressure oil chamber. A cylindrical member having the shoe portion slidably in contact with the outer peripheral surface of the member, at least one end of which is opened in the axial direction; and an annular plate member joined to one end of the cylindrical member so as to close the opening. In the valve opening / closing timing control device constituted by the above, the lock mechanism is provided in the plate member, and the plate member is supported on the rotor member so as to be relatively rotatable on the inner periphery thereof.
The lock mechanism is slidably assembled to the plate member and is urged toward the rotor member, and a lock member having a rectangular cross section is formed on the rotor member. The tip part is composed of a lock recess that can be accommodated so as not to move in the circumferential direction,
The plate member includes a first plate whose one side closes the opening of the cylindrical member and a second plate joined to the other side of the first plate, and the first plate is connected to the second plate. A groove that opens to the other side surface of the plate and opens radially inward is provided, and the lock member is accommodated in the groove .
[0009]
[Operation and effect of the invention]
In the valve opening / closing timing control device according to the present invention, since the lock mechanism is provided in the plate member, it is not necessary to make the vane portion thick in the circumferential direction as in the conventional device. It is possible to prevent the number of vane portions from being limited. For this reason, the circumferential thickness of the vane portion can be reduced, and as a result, the phase conversion angle can be increased, the variable control region of the valve opening / closing timing control device can be increased, and the number of vane portions can be increased. Can be increased, and the responsiveness of the valve timing control device can be improved.
[0010]
Further, when the lock mechanism is constituted by a lock member having a rectangular cross section accommodated in a groove formed in the second plate of the housing member, and a recess formed in the rotor member and capable of accommodating the distal end portion of the lock member Since the contact area of the lock member with the second plate and the rotor member can be increased, the strength of the lock mechanism can be improved. Further, since the strength of the lock mechanism can be improved, the size can be reduced, and the valve opening / closing timing control device can be reduced in size.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The valve opening / closing timing control device according to the present invention shown in FIGS. 1 to 7 is provided with a rotor member 20 that is integrally assembled at the tip of the camshaft 10 and is externally mounted on the rotor member 20 so as to be relatively rotatable within a predetermined range. A housing member 30, a torsion spring S that is interposed between the housing member 30 and the rotor member 20 and constantly urges the rotor member 20 toward the advance side with respect to the housing member 30, and the housing member 30 and the rotor member 20. A stopper mechanism A that defines an initial phase (most retarded angle position) and a most advanced angle position, and a lock mechanism B that regulates relative rotation of the housing member 30 and the rotor member 20 in the initial phase, and an advanced angle oil described later. A hydraulic circuit C is provided for controlling the supply and discharge of hydraulic oil to and from the chamber R1 and the retarded angle oil chamber R2 and for controlling the lock / unlock of the lock mechanism B.
[0012]
The camshaft 10 has a known cam (not shown) that opens and closes an intake valve (not shown), and is rotatably supported by a cylinder head 40 of the internal combustion engine. An advance passage 11 and a retard passage 12 extending in the direction are provided. The advance passage 11 is connected to the connection port 101 of the control valve 100 through the radial passage 13, the annular passage 14, and the connection passage P1. The retard passage 12 is connected to the connection port 102 of the control valve 100 via a radial passage 15, an annular passage 16, and a connection passage P2. The radial passages 13 and 15 and the annular passage 16 are formed in the camshaft 10, and the annular passage 14 is formed between the steps of the camshaft 10 and the cylinder head 40.
[0013]
The control valve 100 forms a hydraulic circuit C with an oil pump 110, an oil reservoir 120, etc., and can move the spool 140 to the left in FIG. In the non-energized state, the supply port 106 connected to the oil pump 110 driven by the internal combustion engine communicates with the connection port 102, and the connection port 101 communicates with the discharge port 107 connected to the oil reservoir 120. Further, in the energized state of the first set current, the supply port 106 and the discharge port 107 are disconnected in the energized state of the second set current that is larger than the first set current so that the communication between the connection ports 101 and 102 is interrupted. The port 106 communicates with the connection port 101 and the connection port 102 communicates with the discharge port 107 It is configured so that.
[0014]
For this reason, in the energized state of the solenoid 103, hydraulic oil is supplied from the oil pump 110 to the retard passage 12, and the hydraulic oil is discharged from the advance passage 11 to the oil reservoir 120, and in the energized state of the first set current. The hydraulic oil is stored in the advance passage 11 and the retard passage 12, and when the second set current is applied, the hydraulic oil is supplied from the oil pump 110 to the advance passage 11 and the oil is supplied from the retard passage 12. At 120, hydraulic oil is discharged.
[0015]
The rotor member 20 is composed of a main rotor 21, a stepped cylindrical front rotor 22 and a stepped cylindrical rear rotor 23 that are integrally assembled before and after the main rotor 21 (left and right in FIG. 1). The central inner holes of the rotors 21, 22, and 23, which are integrally fixed to the front end of the camshaft 10 by bolts 50 and closed at the front ends by the heads of the bolts 50, are advance passages provided in the camshaft 10. 11 communicates.
[0016]
The main rotor 21 includes a hub portion 21a in which the front rotor 22 and the rear rotor 23 are coaxially assembled, and the four advance oil chambers R1 and the retard angle in the housing member 30 extending radially outward from the hub portion 21a. There are four vane portions 21b that define the oil chamber R2, and a sealing member 24 for sealing between the advance oil chamber R1 and the retard oil chamber R2 at the radially outer end of each vane portion 21b. Are assembled respectively.
[0017]
The hub portion 21a of the main rotor 21 has four radial passages 21c that communicate with the advance passage 11 through the central inner hole at the radially inner end and communicate with the advance oil chamber R1 at the radially outer end. An axial passage 21d that communicates with the retarded passage 12 and a radial passage 21e that communicates with the passage 21d at the radially inner end and communicates with the retarded oil chamber R2 at the radially outer end are provided. Four each are provided.
[0018]
Two of the four axial passages 21d facing each other (shown in the upper left and lower right in FIGS. 4 to 6) penetrate the main rotor 21 in the axial direction and are provided in the rear rotor 23 in the axial direction. The remaining two opposing ones (shown in the upper right and lower left in FIGS. 4 to 6) are connected to the main rotor through the passage 23a and the annular passage 23b (see FIGS. 1 and 3). 21 is opened only on the front side, and communicates with an axial passage 21d penetrating through a pair of arc-shaped communication grooves 22a (see FIGS. 1 and 5) formed on the rear surface of the front rotor 22. The axial hole 21f shown in the upper part of FIGS. 4 to 6 is for attaching a pin (not shown) for connecting the main rotor 21 and the front rotor 22.
[0019]
The housing member 30 integrally connects a housing body (cylindrical member) 31, a front plate 32, a rear thin plate (first plate) 33, and a rear thick plate (second plate) 34. A sprocket 34 a is integrally formed on the outer periphery of the rear thick plate 34. As is well known, the sprocket 34a is connected to a timing chain (not shown) and configured to transmit a driving force from the crankshaft.
[0020]
The housing body 31 has two pairs of four shoe portions 31a projecting inward in the radial direction, and the hub portion 21a of the main rotor 21 is connected to the inner end of each shoe portion 31a in the radial direction via a seal member 36. It is supported so that it can rotate relatively. The front plate 32 and the rear thin plate 33 are axially opposed end surfaces, the outer periphery of the hub portion 21ao axial direction end surface of the main rotor 21, the entire axial end surface of each vane portion 21b, and the axial direction of each seal member 36. The entire end face is slidably in contact with each other.
[0021]
As shown in FIGS. 1 and 7, the rear thick plate 34 is opened to the front side and radially inward, and the front side opening is formed on the rear thin plate 33 (in FIG. 7, only the inner peripheral edge is an imaginary line). The hub portion 34c has an accommodation groove 34b that is closed by the inner circumference of the hub portion 34c, and is supported on the outer circumference of the rear rotor 23 so as to be relatively rotatable. A lock key 61 and a lock spring 62 are assembled.
[0022]
The lock key 61 is formed to have a rectangular cross section, and is always urged toward the outer periphery of the hub portion 23c of the rear rotor 23 with the radially inner end portion 61a. On the radially outer side of the lock key 61, a groove 61 b is formed that opens to the front side and radially outward to receive a part of the lock spring 62. Note that the radially outer end of the accommodation groove 34b is opened through a through hole 34d (see FIGS. 1 and 3), and the rapid radial movement of the lock key 61 is guaranteed.
[0023]
On the outer periphery of the hub portion 23c of the rear rotor 23, as shown in FIG. 7, there is formed a lock recess 23f that can accommodate the distal end portion 61a of the lock key 61 in the initial phase (most retarded position) so as not to move in the circumferential direction. ing. In the bottom of the lock recess 23f, a radial through hole 23h communicating with the advance passage 11 is opened at the radially inner end, and when hydraulic oil is supplied from the advance passage 11 through the through hole 23h. When the lock key 61 is pushed radially outward against the lock spring 62 and retracts to the position indicated by the phantom line in FIG. 7, the hydraulic oil is discharged into the advance passage 11 through the through hole 23h. The lock key 61 is pushed toward the lock recess 23f by the urging force of the lock spring 62 so that the front end 61a of the lock key 61 is fitted into the lock recess 23f and accommodated.
[0024]
In the present embodiment, a groove extending in the axial direction is formed on the inner periphery of the rear thick plate 34, and a knock key 70 is press-fitted and fixed in the groove. The radially inner end of the knock key 70 protrudes from the inner periphery of the rear thick plate 34, extends in the circumferential direction on the outer periphery of the hub portion 23 c of the rear rotor 23, and is housed in a free recess 23 d formed in an arc shape. 30 and the rotor member 20 are accommodated in a state allowing relative rotation. At one end in the circumferential direction of the free recess 23d, a stopper surface 23e that defines the initial phase is formed by contact with the radially inner end of the knock key 70. Further, a second stopper surface 23g that defines the maximum relative rotation amount (maximum advance angle position) of the rotor member 20 with respect to the housing member 30 is formed at the other circumferential end of the free recess 23d so as to face the stopper surface 23e. Has been.
[0025]
In the present embodiment configured as described above, hydraulic oil is supplied to the advance passage 11 and the retard passage 12 from the oil pump 110 driven by the start of the internal combustion engine via the control valve 100 when the internal combustion engine is started. When not, the lock key 61 is fitted into the lock recess 23f by the urging force of the lock spring 62 as shown in FIG.
[0026]
Therefore, even when positive / negative reversal torque is generated in the camshaft 10 when the intake valve is driven, the relative rotation of the rotor member 20 relative to the housing member 30 is restricted by the lock key 61. Rotational vibration is not generated, and hitting sound associated with the rotational vibration is prevented. If the control valve 100 is in the non-energized state of FIG. 1 when the internal combustion engine is started, hydraulic oil is supplied from the oil pump 110 to the retard passage 12 through the control valve 100, and the retard oil chamber R2 is supplied. From the point of time when the hydraulic oil is supplied, the relative rotation between the rotor member 20 and the housing member 30 is restricted by the hydraulic pressure in the retarded oil chamber R2.
[0027]
In this state, when the solenoid 103 of the control valve 100 is switched from a non-energized state to a second set current energized state, the supply port 106 communicates with the connection port 101 and the connection port 102 communicates with the discharge port 107. The hydraulic oil is supplied to the advance passage 11 and the hydraulic oil is discharged from the retard passage 12 to the oil reservoir 120. Therefore, hydraulic fluid is supplied from the advance passage 11 to the lock recess 23f through the through hole 23h of the rear rotor 23, and hydraulic oil is supplied from the advance passage 11 to the advance oil chamber R1 through the passage 21c of the main rotor 21. Then, hydraulic oil is discharged from the retard oil chamber R2 to the retard passage 12 through the passages 21e and 21d of the main rotor 21.
[0028]
Accordingly, the hydraulic oil supplied to the lock recess 23f pushes the lock key 61 radially outward against the lock spring 62 to move and retract from the solid line position to the virtual line position in FIG. The rotor member 20 is pushed in the clockwise direction of FIG. 4 by the hydraulic oil supplied to the oil chamber R1, and rotates relative to the housing member 30 from the most retarded position to the advanced side. The relative rotation of the rotor member 20 with respect to the housing member 30 is possible until the second stopper surface 23g formed on the rear rotor 23 comes into contact with the radially inner end of the knock key 70.
[0029]
Further, when the solenoid 103 of the control valve 100 is switched from the energized state of the second set current to the energized state of the first set current, the supply port 106 and the discharge port 107 are disconnected from the connection ports 101 and 102. The hydraulic oil is stored in the advance passage 11 and the retard passage 12, so that the hydraulic oil is stored in the advance oil chamber R1 and the retard oil chamber R2, and the rotor member 20 is relative to the housing member 30. Rotation is regulated.
[0030]
When the solenoid 103 of the control valve 100 is switched from the energized state of the first set current to the non-energized state, the supply port 106 communicates with the connection port 102, and the connection port 101 communicates with the discharge port 107, thereby retarding the angle. The hydraulic oil is supplied to the passage 12 and is discharged from the advance passage 11 to the oil reservoir 120. Therefore, hydraulic oil is supplied from the retard passage 12 to the retard passage R2 through the passages 21d and 21e of the main rotor 21, and the hydraulic oil is discharged from the advance oil chamber R1 to the advance passage 11 through the passage 21c of the main rotor 21. Is done.
[0031]
Therefore, the rotor member 20 is pushed counterclockwise in FIG. 4 by the hydraulic oil supplied to the retard oil chamber R2, and rotates relative to the housing member 30 toward the retard side. The relative rotation of the rotor member 20 with respect to the housing member 30 is possible until the stopper surface 23e formed on the rear rotor 23 comes into contact with the radially inner end of the knock key 70. At this time, since the hydraulic oil can be discharged from the lock recess 23f to the advance passage 11, the rotor member 20 is moved to the most retarded position where the stopper surface 23e formed on the rear rotor 23 and the radially inner end of the knock key 70 abut. When the housing member 30 is rotated relative to the housing member 30, the lock key 61 is pushed by the lock spring 62, and the distal end portion 61a of the lock key 61 is fitted into the lock recess 23f and accommodated.
[0032]
As is apparent from the above description, in this embodiment, the relative rotation position of the rotor member 20 with respect to the housing member 30 is most advanced from the most retarded position by controlling the energization state of the control valve 100 to the solenoid 103. It can be adjusted to any position within the range up to the angular position, and the valve opening / closing timing when the internal combustion engine is driven can be adjusted appropriately. When the internal combustion engine is stopped, the energization state of the solenoid 103 is controlled so that the distal end portion 61a of the lock key 61 is fitted and accommodated in the lock recess 23f.
[0033]
By the way, in the present embodiment, the lock mechanism B is slidably accommodated in the accommodating groove 34b formed in the rear thick plate 34, and the distal end portion 61a is always attached radially inward by the lock spring 62. The lock key 61 has a rectangular cross section to be urged, and a lock recess 23f formed on the outer periphery of the rear rotor 23 that supports the inner periphery of the rear thick plate 34 so as to be relatively rotatable. For this reason, since it is not necessary to make the vane part 21b thick in the circumferential direction unlike the conventional apparatus, it is possible to prevent the phase conversion angle and the number of the vane parts 21b from being limited by the lock mechanism B. For this reason, the thickness in the circumferential direction of the vane portion 21b can be reduced, and as a result, the phase conversion angle can be increased, the variable control region of the valve timing control device can be increased, and the vane portion 21b. Can be increased, and the responsiveness of the valve timing control device can be improved.
[0034]
Further, by using the lock key 61 having a rectangular cross section, the contact area between the lock key 61 and the receiving groove 34b and the lock recess 23f can be increased, and the strength of the lock mechanism B, the rear thick plate 34, and the rear rotor 23 can be increased. Can be improved. As a result, the rear thick plate 34 and the rear rotor 23 can be downsized, and the valve opening / closing timing control device can be downsized.
[0035]
Further, in the conventional valve timing control device, since the lock member is disposed in the vane portion, the vane portion in which the lock member is disposed is arranged in the circumferential direction compared to the vane portion in which the lock member is not disposed. It needs to be formed thick, and unbalance occurs when the rotor member rotates. Further, since the housing member is also formed with a tapered hole, unbalance is similarly generated. As a result, vibration may occur due to these imbalances during the operation of the internal combustion engine, and the vibration may resonate with other components of the internal combustion engine to generate abnormal noise. In order to eliminate these problems, for example, in order to eliminate the unbalance of the rotor member, the vane portion where the lock member is disposed and the vane portion symmetrical to the rotation axis of the rotor member are balanced. It is possible. However, for this purpose, design considerations such as adding a mass by increasing the thickness of the symmetrical vane portion, etc. are required. As a result, the increase in the weight of the valve opening / closing timing control device and the phase conversion angle are required. This results in a restriction on the maximum value of.
[0036]
On the other hand, in this embodiment, the rear thick plate 34 is unbalanced. This unbalance is caused by, for example, the axis of the portion of the rear thick plate 34 in which the housing groove 34b for housing the lock key 61 is formed. The valve opening / closing timing control device is provided by providing a recess or notch in a symmetric part, or providing a notch in a part of the rear thin plate 33 that is symmetrical to the part of the rear thick plate 34 where the receiving groove 34b is formed. This can be solved without incurring the increase in the weight and the restriction on the maximum value of the phase conversion angle.
[0037]
In the present embodiment, the present invention is implemented to control the opening / closing timing of the intake valve (not shown). However, the present invention can also be implemented to control the opening / closing timing of the exhaust valve.
[0038]
Further, in the above embodiment, the present invention has been implemented in such a manner that the rotor member 20 is assembled on the camshaft 10 side and the housing member 30 is assembled on the crankshaft side. It is also possible to implement the present invention so that the housing member is assembled to the camshaft side.
[Brief description of the drawings]
1 is a cross-sectional view taken along line 1-1 of FIG. 3 showing an embodiment of a valve timing control apparatus according to the present invention.
2 is a front view of the valve timing control apparatus shown in FIG. 1. FIG.
FIG. 3 is a rear view of the valve opening / closing timing control device shown in FIG. 1;
4 is a cross-sectional view taken along line 4-4 of FIG. 1 in which the sprocket shown in FIG. 1 is omitted.
5 is a cross-sectional view taken along line 5-5 of FIG. 1 in which the sprocket and the front rotor shown in FIG. 1 are omitted.
6 is a cross-sectional view taken along line 6-6 of FIG. 1 in which the sprocket shown in FIG. 1 is omitted.
7 is a cross-sectional view taken along line 7-7 in FIG.
[Explanation of symbols]
10 Camshaft (driven shaft)
20 rotor member 21 main rotor 21a main rotor hub portion 21b vane portion 22 front rotor 23 rear rotor 23c rear rotor hub portion 23f lock recess 23h through hole 30 housing member 31 housing body (cylindrical member)
31a Shoe portion 32 Front plate 33 Rear thin plate (first plate)
34 Rear thick plate (second plate)
34b Housing groove (groove)
34c Hub part of rear thick plate 61 Lock key (lock member)
62 Lock spring 100 Control valve 110 Oil pump 120 Oil reservoir R1 Advance oil chamber R2 Delay oil chamber B Lock mechanism C Hydraulic circuit

Claims (1)

A housing member that is provided in a driving force transmission system that transmits a driving force from a driving shaft of an internal combustion engine to a driven shaft that opens and closes at least one of an intake valve and an exhaust valve, and rotates integrally with the driving shaft or the driven shaft;
Advancing oil chamber and retard oil chamber are formed in the housing member at the vane portion so as to be relatively rotatable to a pair of shoe portions provided in the housing member, and integrated with the driven shaft or the drive shaft. A rotating rotor member,
A lock mechanism for restricting relative rotation of the housing member and the rotor member at an initial phase of the housing member and the rotor member;
A hydraulic circuit that controls supply and discharge of hydraulic oil to and from the advance oil chamber and the retard oil chamber, and controls locking and unlocking of the lock mechanism,
The housing member has the shoe portion that is in sliding contact with the outer peripheral surface of the rotor member, and at least one axial end of the cylindrical member is open,
In the valve opening / closing timing control device comprising an annular plate member joined to one end of the cylindrical member so as to close the opening,
The lock mechanism is provided in the plate member, and the plate member is supported on the rotor member so as to be relatively rotatable on the inner periphery thereof.
The lock mechanism is slidably assembled to the plate member and is urged toward the rotor member. The lock member is formed on the rotor member and is formed at the initial phase. The tip part is composed of a lock recess that can be accommodated so as not to move in the circumferential direction,
The plate member includes a first plate whose one side closes the opening of the cylindrical member and a second plate joined to the other side of the first plate, and the first plate is connected to the second plate. A valve opening / closing timing control device characterized in that a groove is formed on the other side surface of the plate and opens radially inward, and the lock member is accommodated in the groove .

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