JP4016527B2 - Valve timing control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a valve opening / closing timing control device used for controlling the opening / closing timing of an intake valve or an exhaust valve in a valve operating apparatus for an internal combustion engine.
[0002]
[Prior art]
As one of the valve opening / closing timing control devices of this type, a rotating member that rotates together with a camshaft of an internal combustion engine, a rotation transmission member that is mounted on the rotating member so as to be relatively rotatable within a predetermined range, and that rotates together with a crankshaft, the rotation A vane provided on the rotating member so as to divide the concave portion formed on the inner peripheral surface of the transmission member into an advance angle chamber and a retard angle chamber, and the rotation transmission member has the concave portion on the inner peripheral surface. A cylindrical housing member whose both ends in the axial direction are open, and the radially outer side of the housing member so that the openings are closed and slidably contact the outer peripheral sides of both end surfaces in the axial direction of the vane and the rotating member. Annular first and second plate members fastened by bolts at one side, a housing member, and the first and second plate members are integrally connected to a crankshaft via a timing chain. There is made is composed of a timing sprocket, for example, disclosed in Japanese Patent Laid-Open No. 10-141022.
[0003]
According to this valve opening / closing timing control device, the hydraulic oil is supplied to the advance chamber and the hydraulic oil is discharged from the retard chamber, whereby the rotating member and the rotation transmitting member are relatively rotated in one direction, and the crankshaft The rotational phase of the camshaft is advanced with respect to the rotational phase of the valve, and the opening / closing timing of the valve driven by the camshaft is advanced. On the contrary, by supplying the hydraulic oil to the retarding chamber and discharging the hydraulic oil from the advance chamber, the rotating member and the rotation transmitting member rotate relative to each other, and the cam rotates with respect to the crankshaft rotation phase The opening / closing timing of the valve driven by the camshaft is delayed by delaying the rotational phase of the shaft.
[0004]
[Problems to be solved by the invention]
The change of the relative rotational phase between the crankshaft and the camshaft is performed based on the difference in hydraulic pressure acting on the advance angle chamber and the retard angle chamber. Therefore, the leakage of hydraulic oil between the advance chamber and the retard chamber greatly affects the performance of the valve timing control device.
[0005]
However, in the valve opening / closing timing control device disclosed in the above-mentioned publication, when the first and second plate members are fastened with bolts to both ends of the housing member at their radially outer portions, each plate member Although the fastening part of the plate member is deformed in the elastic region by the fastening force, the inner peripheral part of each plate member (the radially inner part) is not deformed, so that the inner peripheral part of each plate member is lifted from the end face of the vane and the rotating member. It is fastened to the housing member in a state. This phenomenon appears remarkably in the plate member on the low rigidity side where the timing sprocket is not adjacent. As a result, the clearance (side clearance) between each plate member and the vane and the rotating member increases, the amount of hydraulic oil leaking through the clearance increases, and the operation responsiveness of the valve timing control device is increased. There was a problem of lowering.
[0006]
Therefore, an object of the present invention is to suppress the leakage of hydraulic oil through the side clearance with a simple configuration and maintain good operation responsiveness in the valve timing control apparatus.
[0007]
[Means for Solving the Problems]
The technical means of the present invention taken in order to solve the above problems includes a rotating member that rotates together with either a crankshaft or a camshaft of an internal combustion engine, and the crankshaft that is mounted on the rotating member so as to be relatively rotatable within a predetermined range. Or a rotation transmission member that rotates together with the other of the camshafts, and a recess formed in the inner peripheral surface of the rotation transmission member so as to partition into an advance angle chamber and a retard angle chamber. A cylindrical housing member having at least one axial end thereof, the rotation transmitting member having the concave portion on the inner peripheral surface thereof slidingly contacting the outer peripheral surface of the rotating member, and the housing member the one end, so as to close the opening in sliding contact with the axial end faces of the vanes and the rotating member is constituted by an annular plate member which is joined at its radially outward portion In becomes the valve timing control apparatus, the one side of said plate member which is joined to one end of said housing member, is that the inner peripheral portion is formed to have a conical shape protruding to the housing member and the rotating member side.
[0008]
According to the above-described means, when the plate member is fastened to one end of the housing member at the radially outer portion, the fastening portion of the plate member is deformed within the elastic region by the fastening force, and the inner periphery of the plate member The portion (radially inner portion) is not deformed, but the inner peripheral portion is disposed on one side of the plate member so as to have a protruding amount corresponding to the amount of lifting of the inner peripheral portion from the vane and the rotating member end surface due to the deformation. It is formed in a conical shape protruding toward the housing member and the rotating member. For this reason, after the plate member is fastened, one side surface of the plate member closely follows the end surface of the housing, the vane, and the rotating member, and the clearance between the plate member, the vane, and the rotating member is appropriately maintained uniformly. As a result, leakage of hydraulic oil through the clearance between the plate member, the vane and the rotating member is suppressed, and the operation responsiveness of the valve opening / closing timing control device is maintained.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a valve timing control apparatus according to the present invention will be described with reference to the drawings.
[0010]
The valve opening / closing timing control device shown in FIGS. 1 to 3 includes a rotating member comprising a rotor 30 integrally assembled with the tip of a camshaft 20 rotatably supported by a cylinder head 10 of an internal combustion engine, and a cam A rotation transmission member including a housing 40, a front plate 50, a cap 54, a rear plate 60, a timing pulley 70, and the like, which are externally mounted on the shaft 20 and the rotor 30 so as to be relatively rotatable within a predetermined range, and six pieces assembled to the rotor 30. The vane 80 and a lock pin (not shown) assembled to the housing 40 are configured. As is well known, the timing pulley 70 is rotated in the clockwise direction in FIG. 2 (counterclockwise in FIG. 3) from the crankshaft 11 of the internal combustion engine via a crank pulley (not shown) and a resin or rubber timing belt 12. Is transmitted. The power transmission from the crankshaft to the rotation transmission member can also be carried out through a timing chain or a timing gear that is employed instead of the timing belt.
[0011]
The camshaft 20 has a known cam (not shown) for opening and closing an intake valve (not shown), and an advance angle passage 21 and a retard angle passage 22 extending in the axial direction of the camshaft 20 are provided inside. ing. The advance passage 21 is connected to the first connection port of the control valve 100 through the radial passage 25, the annular oil passage 13, and the connection passage 14. The retard passage 22 is connected to the second connection port of the control valve 100 via the radial passage 26, the annular oil passage 15, and the connection passage 16.
[0012]
The control valve 100 is capable of moving the spool to the left in FIG. 1 against a spring (both are not shown in detail) by energizing the solenoid 101, and an oil pump 110 driven by the internal combustion engine when not energized. The supply port connected to the first connection port communicates with the second connection port, and the first connection port communicates with the discharge port communicated with the oil pan 111 (first position 102). The second connection port communicates with the connection port and the second connection port communicates with the discharge port (second position 103). For this reason, when the solenoid 101 of the control valve 100 is not energized, the hydraulic oil is supplied from the oil pump 110 to the retard passage 22 and discharged from the advance passage 21 to the oil pan 111, and from the oil pump 110 when energized. The hydraulic oil is supplied to the advance passage 21 and discharged from the retard passage 22 to the oil pan 111. The energization of the solenoid 101 is duty-controlled by a control device (not shown). When the duty is 50%, the control valve 100 controls the connection passages 14 and 16 to the third position 104 not communicating with the oil pump 110 or the oil pan 111. Is done.
[0013]
The rotor 30 is made of an iron-based material, and is integrally fixed to the camshaft 20 by a bolt 23 that passes through the stepped inner hole. The vane 80 is used to attach each vane 80 made of an iron-based material in the radial direction. In the state shown in FIG. 2, that is, when the relative phase of the camshaft 20 and the rotor 30 and the housing 40 reaches a predetermined phase (most retarded angle position), the head of a lock pin (not shown) is positioned. It has a receiving hole 32 into which a fixed amount is inserted. Further, the rotor 30 is formed between the rotor rear end surface and the rear plate 60 and the front end step portion of the camshaft 20, and one end thereof is opened in an annular space 39 communicating with the advance passage 21, and the other end is the rotor. The hydraulic oil passes through the shaft passage 33 from the advance passage 21 to the advance chambers R1 and R1a defined by the three vanes 80 and the three shaft passages 33 extending in the axial direction so as to open to the front end surface. Between the groove passage 35 formed on the front end surface of the rotor so as to supply and discharge, the large diameter hole of the stepped inner hole of the rotor 30, and the small diameter portion of the camshaft 20 fitted into the large diameter hole. A passage 38 for supplying and discharging hydraulic oil from the retard passage 22 to the retard chamber R2 defined by the vanes 80 through the annular space 37 formed and communicated with the retard passage 22 is provided. Further, a groove-shaped passage 53 for supplying and discharging hydraulic oil from the retard chamber R2a to the receiving hole 32 is formed on the outer periphery of the rotor 30. The retarding passage 22 is formed between the mounting hole 24 formed in the camshaft 20 and the bolt 23, and the annular space 37 and the annular space 39 are the leading end portion of the camshaft 20 and the rotor rear end surface. The cylindrical part formed in the above is liquid-tightly isolated by being crimped by tightening the bolt 23. Each vane 80 is urged radially outward by a spring 81 (see FIG. 1) accommodated between the bottom of the vane groove 31 and a groove 81 formed at the inner end of each vane 80.
[0014]
The housing 40 is made of an iron-based material, and is assembled to the outer peripheral surface of the rotor 30 on the inner periphery thereof so as to be relatively rotatable with a predetermined clearance (minimum clearance through which hydraulic oil (film) is interposed). Is formed by joining an annular front plate 50 made of an aluminum alloy and an annular rear plate 60 made of an iron-based material via seal members 51 and 61, and so on in the circumferential direction at the radially outer end portion of each plate 50 and 60. The bolts 62 are integrally connected to the interval. Thereby, the front plate 50 and the rear plate 60 are slidably contacted with each vane 80 with a predetermined clearance (minimum clearance through which hydraulic oil (film) is interposed), and the radially inner end portion of the front plate 50 and the rear plate 60. The radially inner end portions of the rotor 30 are slidably contacted with the radially outer end portions of both end faces of the rotor 30 with a predetermined clearance (minimum clearance through which hydraulic oil (film) is interposed). A cap 54 is assembled in a liquid-tight manner on the front plate 50, thereby forming a passage 34 connecting the advance passage 21 of the camshaft 20 and the shaft passage 33 of the rotor 30 and the groove passage 35 of the rotor 30. ing. The housing 40 accommodates each vane 80, and the working chamber R divided into the advance chambers R1 and R1a and the retard chambers R2 and R2a by the vanes 80 is divided into the rotor 30, the front plate 50, and the rear plate. In addition, a recess 41 is formed, and a retraction hole 42 that accommodates a lock pin (not shown) and a spring (not shown) that urges the lock pin toward the rotor 30 is formed in the radial direction of the housing 40. In FIG. 1, reference numeral 17 denotes an oil seal assembled to the cylinder head 10 so as to engage with the outer periphery of the cylindrical portion of the rear plate 60. The cylindrical portion is an O-ring on the outer periphery of the camshaft 20 at the inner periphery. Is rotatably mounted with a predetermined clearance, and is not substantially supported on the outer peripheral surface of the camshaft 20.
[0015]
The retreat hole 42 is liquid-tightly closed at its outer end by a plug and a seal member, and a back pressure chamber is formed at the back of the lock pin. In the present embodiment, as shown in FIG. 3, the back pressure chamber has a passage 49, a passage 48, and a passage 48a provided in the housing 40 (the passages 48, 48a are grooves on the side surface of the housing 40 on the rear plate 60 side). The lead angle chamber R1a always communicates with the advance angle chamber R1a. As shown in FIG. 2, the back pressure chamber can communicate with the passage 34 through a passage 46 and a passage 45 provided in the housing 40 and a groove passage 36 provided in the rotor 30. The passage 45 and the groove passage 36 are configured such that the relative phase between the rotor 30 and the housing 40 is a predetermined angle (the most retarded angle position shown in FIGS. 2 and 3) with respect to the housing 30. 2 in such a way that the rotor 30 is rotated in a range up to a phase that is relatively rotated in the clockwise direction, and the communication is interrupted when the rotor 30 rotates relative to the housing 40 from the most retarded position to the advance side by a predetermined angle or more. Has been. The plug is prevented from coming off by a timing pulley 70 fixed to the housing 40 by three bolts 71 at protrusions formed on the outer periphery of the housing 40 at equal intervals in the circumferential direction.
[0016]
Further, in the present embodiment, the vane 80 located in the working chamber R abuts on a stopper portion formed at the radially inner end of the circumferential end surface of the recess 41 that defines the lower left working chamber R in FIG. Thus, the phase (relative rotation amount) adjusted by the valve opening / closing timing control device is limited. As shown in FIGS. 2 and 3, the groove passages 35 are formed in the stopper portions when the vanes 80 are in contact with the stopper portions (at the most retarded angle and the most advanced angle). A communication groove is formed so that the passage 38 communicates with the retard chambers R2 and R2a (lower right in FIG. 3: at the most advanced angle) (lower left in FIG. 2: at the most retarded angle).
[0017]
In the valve opening / closing timing control apparatus of the present embodiment configured as described above, when the internal combustion engine is stopped, each member is in the state shown in FIGS. 1 to 3 (the retarding chambers R2 and R2a have the largest volumes and the maximum volume). The oil pump 110 is stopped and hydraulic oil is not supplied to the connection passages 14 and 16 in a state of being retarded and locked by a lock pin (not shown). When the internal combustion engine is started in this state, hydraulic oil is supplied from the oil pump 110 to the connection passage 16 via the control valve 100 in a non-energized state for at least a predetermined time. The working oil is supplied to the retarding chambers R 2 and R 2 a through the passage 22 and the passage 38, and is supplied to the receiving hole 32 through the passage 53. At the same time, the connection passage 14 is communicated with the oil pan 111 via the control valve 100 in a non-energized state, whereby the advance chambers R1, R1a are communicated with the oil pan 111 through the passage 35, the advance passage 21, and the like. The At this time, a predetermined time is required until a predetermined amount of hydraulic oil is supplied to the receiving hole 32, and the head of the lock pin (not shown) is inserted into the receiving hole 32 until a predetermined time has elapsed since the start of the internal combustion engine. Therefore, unnecessary relative rotation of the rotor 30 and the housing 40 due to a large torque fluctuation of the camshaft 20 at the start of the internal combustion engine is restricted, and a problem associated with unnecessary relative rotation of the rotating member and the rotation transmitting member. (For example, the hitting sound by the vane 80) can be eliminated.
[0018]
After a predetermined time has elapsed since the start of the internal combustion engine, the lock pin is moved toward the retraction hole 42 against the urging force of the spring by the hydraulic oil supplied to the receiving hole 32, and the lock pin of the rotor 30 and the housing 40. And the rotor 30 can be rotated relative to the housing 40.
[0019]
In this state, by increasing the duty ratio of the current supplied to the solenoid 101 of the control valve 100, when hydraulic fluid is supplied to the advance passage 21 and hydraulic fluid is discharged from the retard passage 22, The rotor 30 rotates relative to the rotation transmission member such as the housing 40 from the most retarded position toward the advanced angle side by the hydraulic oil supplied to the advance chambers R1 and R1a. As a result, the duty ratio of the current supplied to the solenoid 101 of the control valve 100 is increased in accordance with the operating state of the internal combustion engine, the hydraulic oil is discharged from the retard chambers R2, R2a, and the advance chamber R1, By supplying the hydraulic oil to R1a, the rotation transmission member such as the rotor 30 and the housing 40 is rotated relative to each other, and the vane 80 comes into contact with the stopper portion so that the volumes of the retarding chambers R2, R2a are minimized (maximum). Advance angle position). Further, by lowering the duty ratio of the current supplied to the solenoid 101 of the control valve 100 and discharging the hydraulic oil from the advance chambers R1, R1a, and supplying the hydraulic oil to the retard chambers R2, R2a, The rotation transmission member such as the rotor 30 and the housing 40 can be rotated relative to each other to change from the most advanced state to the most retarded position shown in FIGS. As a result, the relative rotational phase between the crankshaft 11 and the camshaft 20 is changed and controlled in accordance with the operating state of the internal combustion engine, so that the opening / closing timing of the intake valve can be accurately controlled in the valve gear of the internal combustion engine. it can. Further, the duty ratio of the current supplied to the solenoid 101 of the control valve 100 is appropriately controlled to supply hydraulic oil to each of the advance chambers R1 and R1a and each of the retard chambers R2 and R2a. It is also possible to keep the relative phase of the housing 40 or the like at an arbitrary phase between the most retarded position and the most advanced position. At this time, since the torque to the retard side is acting on the rotor 30 by the fluctuating torque acting on the camshaft 20, the hydraulic pressure of the advance chambers R1, R1a> the hydraulic pressure of the retard chambers R2, R2a The hydraulic oil is supplied so that
[0020]
As described above, the relative rotation phase between the crankshaft 11 and the camshaft 20 is changed based on the difference in hydraulic pressure acting in the advance chambers R1, R1a and the retard chambers R2, R2a. Therefore, the leakage of hydraulic fluid between the advance chambers R1, R1a and the retard chambers R2, R2a greatly affects the performance of the valve opening / closing timing control device, so the sliding contact portion between each vane 80 and the front plate 50 The sliding contact portion between each vane 80 and the rear plate 60, the sliding contact portion between each vane 80 and the housing 40 and the rotor 30, the sliding contact portion between the front plate 50 and the rotor 30, and the sliding contact between the rear plate 60 and the rotor 30. The predetermined clearance at the contact portion (minimum clearance with hydraulic fluid (film)) must be kept appropriate.
[0021]
The predetermined clearance of these sliding portions is appropriately maintained by managing the dimensional accuracy of each member, but the sliding contact portion between each vane 80 and the front plate 50 and between each vane 80 and the rear plate 60 are maintained. Each clearance (side clearance) of the sliding contact portion, the sliding contact portion between the front plate 50 and the rotor 30 and the sliding contact portion between the rear plate 60 and the rotor 30 is the radial direction of the plates 50 and 60 as described above. Since it is integrally connected to the housing 40 by the bolt 62 at the outer end portion, there is a fear that it will change (increase). That is, when the plates 50 and 60 are fastened to the both ends of the housing 40 by the bolts 62 at the radially outer portions thereof, the fastening portions of the plates 50 and 60 are deformed within the elastic region by the fastening force. Since the inner peripheral portion (radially inner portion) of each plate 50, 60 is not deformed, each plate 50, 60 is fastened to the housing 40 with the inner peripheral portion raised from the vane 80 and the end face of the rotor 30. There is a fear.
[0022]
In the present embodiment, when the front plate 50 is fastened to one end of the housing 40 at the radially outer end portion thereof, the fastening portion of the front plate 50 is deformed within the elastic region by the fastening force, and the front plate 50 Although the inner peripheral portion (the radially inner portion) is not deformed, as shown in FIG. 4, the front portion has a protruding amount corresponding to the lift amount of the inner peripheral portion from the end face of the vane 80 and the rotor 30 due to this deformation. One side 50a side of the plate 50 is formed in a conical shape having an inner peripheral portion protruding toward the housing 40 and the rotor 30 and having an inclination angle θ. For this reason, after the front plate 50 is fastened, one side surface 50a of the front plate 50 follows the end face of the housing 40, the vane 80 and the rotor 30 uniformly, and a predetermined clearance between the front plate 50, the vane 80 and the rotor 30 is obtained. Is maintained properly and uniformly. As a result, leakage of hydraulic oil through the clearance between the front plate 50, the vane 80, and the rotor 30 is suppressed, and the operation responsiveness of the valve timing control device is maintained. Since the rear plate 60 is made of an iron-based material, the deformation of the fastening portion to the housing 40 is small, and the inner peripheral portion of the rear plate 60 does not float significantly from the end surfaces of the vane 80 and the rotor 30. Similarly to the above, the side surface of the rear plate 60 to be joined to the housing 40 may be formed in a conical shape protruding toward the housing 40 and the rotor 30 side.
[0023]
In the above embodiment, the present invention is applied to the valve opening / closing timing control device assembled to the intake camshaft 20, but the present invention is similarly applied to the valve opening / closing timing control device assembled to the exhaust camshaft. It can be implemented.
[0024]
【The invention's effect】
As described above, according to the present invention, the one side of the plate member joined to one end of the housing member is formed in a conical shape with the inner peripheral portion protruding toward the housing member and the rotating member. Thus, leakage of hydraulic oil through the side clearance can be suppressed, and good operation responsiveness can be maintained.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view showing an embodiment of a valve timing control apparatus according to the present invention.
FIG. 2 is a cross-sectional view taken along line BB in FIG.
FIG. 3 is a cross-sectional view taken along the line CC of FIG.
FIG. 4 is a cross-sectional view of the front plate, the rear plate, the housing, and the rotor showing a state before the front plate is fastened to the housing.
[Explanation of symbols]
11 Crankshaft 20 Camshaft 21 Advance passage 22 Retraction passage 30 Rotor (rotating member)
40 Housing (Rotation transmission member, housing member)
41 recess (recess)
50 Front plate (rotation transmission member, plate member)
50a One side surface 60 Rear plate (rotation transmission member, plate member)
80 Vane R1, R1a Advance angle chamber R2, R2a Delay angle chamber

Claims (2)

A rotating member that rotates with one of the crankshaft or camshaft of the internal combustion engine;
A rotation transmitting member that is externally mounted on the rotating member so as to be relatively rotatable within a predetermined range and rotates together with the other of the crankshaft or the camshaft;
A vane provided in the rotating member so as to partition a recess formed in the inner peripheral surface of the rotation transmitting member into an advance angle chamber and a retard angle chamber;
A cylindrical housing member having the concave portion on the inner peripheral surface thereof slidably in contact with the outer peripheral surface of the rotating member, and having at least one axial end thereof opened;
One end of the housing member is composed of an annular plate member joined at the radially outer portion so as to close the opening and to slidably contact the vane and one axial end surface of the rotating member. In the valve timing control device,
The valve opening / closing timing control device according to claim 1, wherein one side surface of the plate member joined to one end of the housing member is formed in a conical shape with an inner peripheral portion protruding toward the housing member and the rotating member.   The valve opening / closing timing control device according to claim 1, wherein the plate member is made of an aluminum alloy.

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