JP4226590B2 - Valve timing control device for internal combustion engine - Google Patents

Description

  The present invention relates to a valve timing control device for an internal combustion engine that makes the opening / closing timing of an intake-side or exhaust-side engine valve of the internal combustion engine variable in accordance with operating conditions.

  As a conventional valve timing control device, one described in Patent Document 1 below is known.

In brief, this valve timing control device is configured such that a timing pulley (driving rotator) that is rotationally driven by a crankshaft of an engine is coaxial with an outer peripheral side of a shaft member (driven rotator) integrally coupled to a camshaft. The timing pulley and the shaft member are connected to each other via an assembly angle adjusting mechanism. The assembly angle adjusting mechanism is formed on a piston member (movable operation member) that is attached to the timing pulley so as to be capable of axial displacement in a state where relative rotation is restricted, and an inner peripheral surface of the piston member and an outer peripheral surface of the shaft member. The piston gear is mainly moved forward and backward in the axial direction by a control mechanism having an electromagnet and a return spring so that the assembly angle of the timing pulley and the shaft member can be adjusted through the helical gear. adjust.
JP-A-10-153104

  However, in this conventional valve timing control device, the piston member (movable operation member) of the assembly angle adjusting mechanism is configured to advance and retract along the axial direction of the camshaft. As a result, the space occupied in the axial direction of the assembly angle adjusting mechanism in the engine increases, and the axial length of the engine becomes longer, resulting in a deterioration in vehicle mountability. In particular, in order to change the piston member advancing / retreating operation position by the electromagnet, the electromagnet must be disposed further outside in the axial direction than the advancing / retreating position of the piston member. It was impossible to install the engine.

  Therefore, the present invention is intended to provide a valve timing control device for an internal combustion engine that can reduce the space occupied in the axial direction of the assembly angle adjusting mechanism and improve the vehicle mountability.

According to the first aspect of the present invention, there is provided a driving rotating body that is rotationally driven by a crankshaft of an engine, a driven rotating body that is a camshaft or a separate member coupled to the camshaft, and a guide that is reduced in diameter in the rotation direction. And a guide plate that engages with the guide and that is guided in a radial direction by a radial guide portion provided on the drive rotator to rotate the guide plate relative to the drive rotator and the driven rotator. A movable operation member that moves in a radially inner direction or a radially outer direction of the guide plate, and a link that connects the movable operation member with a portion spaced a predetermined distance from the center of the driven rotor, An assembly angle adjusting mechanism for changing the assembly angle of the drive rotating body and the driven rotating body by moving the movable operation member in the inner or outer direction; Equipped with a,
The relative rotation phase between the crankshaft and the camshaft is variably controlled by rotating the guide plate relative to the drive rotator according to the engine operating condition.

  In the case of the present invention, since the movable operation member is displaced along the radial direction of the drive rotating body and the driven rotation body, the space occupied in the axial direction of the movable operation member is reduced. As a result, the mounting property on the vehicle is improved.

According to a second aspect of the present invention, there is provided a driving rotating body that is rotationally driven by a crankshaft of an engine, a driven rotating body comprising a camshaft or a separate member coupled to the camshaft, and a guide plate having a spiral guide is guided into the spiral guide Rutotomoni, the guided radially by the radial guide portion provided on the driving rotary member, by relative rotation of the guide plate relative to the drive rotor and the driven rotor A movable operating member that moves in the radially inner direction or radially outward direction of the guide plate, and a link that connects the movable operating member with a portion that is spaced a predetermined distance from the center of the driven rotor. An assembly angle adjusting mechanism for changing the assembly angle of the drive rotator and the driven rotator by moving the operation member in the inner or outer direction; It is characterized by comprising.

According to this invention, as the movable operation member moves in the radially inward or outward direction , one end of the link rotates while being displaced in the radial direction, so that the drive rotator and the driven rotator are relatively rotated. Let Thereby, it is possible to convert the radial movement of the movable operation member into the relative rotation of the driving rotating body and the driven rotating body with an extremely simple structure. For this reason, the assembly angle adjusting mechanism with a small axial occupation space can be manufactured at low cost.

  Next, an embodiment of the present invention will be described.

  First, the first embodiment shown in FIGS. 1 to 6 will be described. Although the valve timing control device of this embodiment is applied to the intake valve side of the internal combustion engine, it can be similarly applied to the exhaust valve side.

  This valve timing control device is rotatably supported by a cylinder head of an engine and has a camshaft 1 having an intake valve driving cam (not shown) on its outer periphery, and is rotatable at the front end of the camshaft 1. A thick disc-like housing 2 attached to the housing, a timing sprocket 3 formed on the outer periphery of one end of the housing 2 and driven to rotate by a crankshaft outside the figure of the engine, an end of the camshaft 1 and the housing 2, an assembly angle adjusting mechanism 4 that variably adjusts the assembly angle of the shaft 1 and the housing 2, and the housing 2 mounted over the cylinder head 5 and the front end surface of the rocker cover (not shown). A VTC cover 6 that surrounds the peripheral area of the assembly angle adjustment mechanism 4 and a controller 7 that controls the assembly angle adjustment mechanism 4 according to the operating state of the engine are provided. In this embodiment, the driven rotor in the present invention is constituted by the camshaft 1, and the drive rotor is constituted by the timing sprocket 3 and the housing 2.

  The housing 2 has a mounting hole 8 formed in the center thereof, and the mounting hole 8 is fitted to the distal end portion of the camshaft 1 so as to be slidable and rotatable, and the peripheral portion of the mounting hole 8 is formed in the camshaft 1. It contacts the locking flange 9 formed integrally. A shallow circular recess 10 is formed on the front end surface of the housing 2 so as to leave a peripheral wall, and guide grooves 11a and 11b (radial direction in the present invention) are formed on the bottom surface of the recess 10 along the radial direction. Guide) is formed, and an opening 12 communicating with the mounting hole 8 is formed at the center. The guide grooves 11 a and 11 b are portions that slidably accommodate and hold movable operation members 14 a and 14 b of an assembly angle adjusting mechanism 4 described later, and each end thereof extends to a vicinity of the outer peripheral wall of the housing 2. . A disc-shaped bore portion 15 is formed at a substantially intermediate position in the axial direction of the housing 2, and link arms 16 a and 16 b of the assembly angle adjusting mechanism 4 described later interfere with the housing 2 by the bore portion 15. To avoid doing.

  The assembly angle adjusting mechanism 4 has a pair of claw portions 17a and 17b extending in opposite directions, a lever member 18 integrally coupled to the end surface of the camshaft 1, and the guide grooves 11a and 11b. The substantially rectangular movable operation members 14a and 14b slidably engaged with each other, the one claw portion 17a and the movable operation member 14a, and the other claw portion 17b and the arcuate shape that connects the movable operation member 14b. The link arms 16 a and 16 b and the actuating device 19 for moving the movable operation members 14 a and 14 b forward and backward based on a control signal from the controller 7 are mainly configured.

  The lever member 18 is formed in a plate shape as a whole, and is fixed to the shaft 1 together with the inner support rod 20 by a fixing bolt 21 in a state where the center portion is overlapped with the tip surface of the camshaft 1. A positioning pin 22 is fitted to the lever member 18 and the camshaft 1, and both are accurately positioned by the pin 22.

  Each of the movable operation members 14a and 14b is formed with a slit 23 at a position spaced a predetermined distance from the rear end face accommodated on the bottom side of the guide grooves 11a and 11b. Each slit 23 has a corresponding link. The distal ends of the arms 16a and 16b are inserted, and in this state, the distal ends are rotatably connected by pins 24. At this time, the base ends of the link arms 16a and 16b are superposed on the upper surfaces of the claw portions 17a and 17b of the lever member 18, and the base ends are connected to the claw portions 17a and 17b by pins 25 in this state. Has been. Accordingly, the movable operation members 14a and 14b accommodated in the guide grooves 11a and 11b are connected to the lever member 18 integrally coupled to the camshaft 1 via the link arms 16a and 16b. When the members 14a and 14b are displaced in the radial direction along the guide grooves 11a and 11b, the housing 2 and the lever member 18, that is, the timing sprocket 3 and the camshaft 1 are moved away from the movable operation members 14a and 14b by the action of the links 16a and 16b. Relative rotation by an angle corresponding to the displacement.

  Further, on the front end surfaces of the movable operation members 14a and 14b, a plurality of arc-shaped ridges 26 (engagement portions in the present invention) are formed in substantially the center of the axis of the camshaft 1, and these protrusions are formed. The strip 26 protrudes from the recess 10 at the front end of the housing 2 in a state where the movable operation members 14a and 14b are engaged with the guide grooves 11a and 11b.

  On the other hand, the actuating device 19 is rotatably supported by the housing 2 and the inner support rod 20, and the guide plate 27 that displaces the movable operation members 14 a and 14 b in the radial direction by its rotation, and the housing 2 and the guide plate 27. Are connected to each other, and a mainspring spring 28 that urges the guide plate 27 in one rotation direction (the same direction as the rotation direction R of the housing 2), and by applying a magnetic force to the guide plate 27, the guide plate 27 is moved in the other rotation direction. And an electromagnet 29 biasing in the direction R ′ opposite to the rotation direction of the housing 2.

  The guide plate 27 is integrally formed with a cylindrical wall 30 extending so as to surround the outer peripheral area of the housing 2 at the outer peripheral end thereof, and the inner peripheral surface of the recessed portion 10 of the housing 2 and the outer periphery of the inner support rod 20. Cylindrical boss portions 31a and 31b engaged with the respective surfaces so as to be slidable and rotatable are projected on the back surface side. Accordingly, the guide plate 27 is supported by the inner support rod 20 and the housing 2 via the inner and outer peripheral cylindrical boss portions 31b and 31a, thereby reliably preventing the tilting and tilting.

  Further, a spiral guide wall 32 (a spiral guide in the present invention) is formed on the back surface of the guide plate 27, and between the adjacent wall surfaces of the guide wall 32, the movable operation members 14 a and 14 b are arranged. The said protrusion 26 engages. As shown in FIG. 4, the spiral of the guide wall 32 is formed so that the diameter gradually decreases along the rotation direction of the housing 2 (R direction in the figure), and the protrusions 26 of the movable operation members 14a and 14b are spirally wound. When the guide plate 27 is rotated in the direction opposite to the housing 2 (R ′ direction in the figure) while being engaged with the guide wall 32, the movable operation members 14a and 14b are moved along the spiral shape of the guide wall 32 at this time. Move radially inward.

  Further, a restriction flange 33 is formed on the outer periphery of the proximal end portion of the inner support rod 20, and the displacement of the guide plate 27 on the front side is restricted by the restriction flange 33. An arc groove 34 extending approximately 360 ° is formed on the contact surface of the guide plate 27 with the regulation flange 33, and a stopper pin 35 protruding from the regulation flange 33 is inserted into the arc groove 34. ing. The stopper pin 35 regulates the rotation adjustment range of the guide plate 27 with respect to the inner support rod 20, that is, the assembly adjustment angle of the housing 2 and the camshaft 1 determined by the radial stroke of the movable operation members 14a and 14b. When the stopper pin 35 comes into contact with one end of the arc groove 34, the maximum assembly angle on the retard side is obtained, and when the stopper pin 35 comes into contact with the end on the opposite side, the maximum assembly angle on the advance side is obtained. It becomes. The stopper pin 35 and the arc groove 34 constitute a stopper mechanism in the present invention.

  On the other hand, the spring 28 is interposed between the outer peripheral surface of the housing 2 and the inner surface of the cylindrical wall 30 of the guide plate 27, and each end is inserted into the notches 36 and 37 on the housing 2 side and the guide plate 27 side. It is locked.

  The electromagnet 29 is attached to the VTC cover 6 so as to face the outer end face of the guide plate 27 in the axial direction.

  Furthermore, from the cylinder head 5 to the camshaft 1, a lubricating oil supply path 38 is formed with a tip opening near the guide grooves 11 a and 11 b of the housing 2, and each movable operation member 14 a, Lubricating oil is supplied to the sliding portion 14b.

  Hereinafter, the operation of the present embodiment will be described.

  At the time of engine start and idle operation, the energization of the electromagnet 29 is turned off by a control signal from the controller 7, and as a result, the guide plate 27 is urged in the same direction as the rotation of the housing 2 only by the force of the spring spring 28. . As a result, the guide plate 27 is maintained at the initial position where the stopper pin 35 abuts one end of the arc groove 34, and the movable operation members 14a and 14b engaged with the spiral guide wall 32 of the guide plate 27 are As shown in FIGS. 1 and 2, the camshaft 1 is displaced to the maximum in the radially outer side, and the camshaft 1 connected to the movable operation members 14a and 14b via the link arms 16a and 16b and the lever member 18 is the housing 2. However, the assembly angle on the most retarded angle side is maintained.

  Therefore, at this time, the rotational phase of the crankshaft and the camshaft 1 is controlled to the most retarded angle side, and engine rotation is stabilized and fuel consumption is improved.

  When the engine shifts to normal operation, energization of the electromagnet 29 is turned on by a control signal from the controller 7, and a magnetic force that imparts rotational resistance to the guide plate 27 is generated in the electromagnet 29. As a result, the rotation of the guide plate 27 that follows and rotates with the housing 2 via the mainspring spring 28 is prevented, the guide plate 27 receives an urging force in the direction opposite to the rotation of the housing 2, and the stopper pin 35 has the arc groove 34. It rotates relative to the housing 2 until it contacts the other end.

  At this time, the contact portion between the protrusion 26 of each movable operation member 14a, 14b and the spiral guide wall 32 is gradually displaced inward in the radial direction, and each movable operation member 14a, 14b is moved to the guide groove 11a, It moves straight inward in the radial direction along 11b. As shown in FIGS. 5 and 6, the connecting point (pin 24) on the distal end side of the link arms 16a and 16b moves inward in the radial direction as the movable operation members 14a and 14b move inward in the radial direction. Then, the base end sides of the link arms 16a and 16b also follow the movement, but at this time, the base end sides of the link arms 16a and 16b are connected to the claws 17a and 17b of the lever member 18 by the pin 25. Therefore, the lever member 18 moves in an arc shape while rotating. As a result, the assembly angle between the housing 2 and the camshaft 1 is adjusted and changed to the most advanced angle state.

  Therefore, at this time, the rotational phase of the crankshaft and the camshaft 1 is controlled to the most advanced angle side, and the engine output is increased.

  The control of the rotation phase of the crankshaft and the camshaft 1 is not limited to switching between the two positions of the retard side and the advance side, but is continuously controlled to an arbitrary rotation phase by appropriately adjusting the magnetic force generated by the electromagnet 29. It is also possible to do.

  The valve timing control device displaces the movable operation members 14a and 14b along the guide grooves 11a and 11b in the radial direction of the housing 2, and also moves the displacement of the movable operation members 14a and 14b in the radial direction of the link arms 16a and 14b. Since the rotation is converted into the relative rotation of the housing 2 and the camshaft 1 through a link mechanism using the lever 16b and the lever member 18, reliable phase control is performed by a compact structure that does not occupy a large space in the axial direction. be able to. The radial operation of the movable operation member 14 is also performed by engaging the spiral guide wall 32 of the guide plate 27 and the protrusion 26 of the movable operation members 14a and 14b. The occupied space in the axial direction is not greatly increased.

  In the case of this apparatus, a spring spring 28 is employed as a spring member for connecting the housing 2 and the guide plate 27, and the spring spring 28 is disposed between the peripheral wall of the housing 2 and the cylindrical wall 30 of the guide plate 27. As a result, the spring member does not increase the axial length of the apparatus.

  Therefore, the axial length of the entire apparatus including the electromagnet 29 is greatly shortened as compared with the conventional one, and the mountability of the engine to the vehicle is surely improved.

  Further, in this apparatus, the guide plate 27 is rotated in the radial direction of the movable operation members 14a and 14b by engaging the spiral guide wall 32 of the guide plate 27 and the protrusions 26 of the movable operation members 14a and 14b. Since it is converted into motion, if the change rate in the radial direction of the spiral of the guide wall 32 is set to be small, the problem that the guide plate 27 rotates due to load input from the movable operation members 14a and 14b side is avoided. be able to. Therefore, by setting in this way, there is no problem that the guide plate 27 is rotationally fluctuated by the fluctuating torque input to the camshaft 1 from the return spring of the engine valve during engine operation, and the control of the valve timing is completed quickly. .

  Furthermore, since this apparatus controls the rotation of the guide plate 27 with respect to the housing 2 by the spring force of the mainspring spring 28 and the magnetic force of the electromagnet 29, it is compared with the case where control is performed using the oil pressure of the oil pump. This eliminates the influence of engine operating speed. Therefore, the valve timing control can be completed promptly regardless of the operating condition of the engine. In addition, since the spring force of the mainspring spring 28 is set in a direction to control the valve timing to the retarded angle side, the engine start is guaranteed even if the electromagnet 29 breaks down.

  Further, the number of the movable operation members 14a and 14b provided is arbitrary as long as it is one or more. However, if a plurality of movable operation members 14a and 14b are provided as in this embodiment, the stress applied to one movable operation member is reduced, and Durability is improved.

  Furthermore, when the lubricating oil supply passage 38 for supplying the lubricating oil is provided to the sliding portions of the movable operation members 14a and 14b as in this embodiment, it is possible to always ensure the smooth operation of the movable operation member. become. In particular, when the lubricating oil supply passage 38 is opened at a position that is radially inward of the movable operating members 14a and 14b as in this embodiment, the lubricating oil is efficiently applied to the movable operating members 14a and 14b by centrifugal force. Can be supplied.

  Next, a second embodiment of the present invention shown in FIGS. 7 and 8 will be described. In addition, the same code | symbol is attached | subjected to the same part as 1st Embodiment, and description shall be abbreviate | omitted about the overlapping part.

  The basic configuration of the apparatus of this embodiment is substantially the same as that of the first embodiment, but the shapes of the movable operation member 114 and the radial guide for guiding it are slightly different.

  That is, the movable operation member 114 is provided with support flanges 40 and 40 extending on both sides thereof in a direction perpendicular to the guide groove 111, and these flanges slide on both upper edges of the guide groove 111. Step portions 41, 41 that are freely engaged are provided. A presser plate 42 is attached to the upper surface side of each stepped portion 41, and a lateral groove 43 that slidably guides the support flange 40 is formed by the stepped portion 41 and the presser plate 42. The lateral grooves 43 together with the support flange 40 constitute a thrust support structure that prevents the movable operation member 114 from rattling in the thrust direction.

  Therefore, the apparatus of this embodiment can obtain the same effects as those of the first embodiment, and can prevent the movable operation member 114 from rattling in the thrust direction. As a result, the link arm 16 and the like are less likely to be twisted during operation, and as a result, the assembly angle adjusting mechanism 4 can be operated smoothly and the durability of the apparatus can be improved.

Sectional drawing which follows the AA line of FIG. 2 which shows the 1st Embodiment of this invention. Sectional drawing which follows the BB line of FIG. 1 which shows the same embodiment. The disassembled perspective view which shows the same embodiment. The C arrow directional view of FIG. 1 which shows the same embodiment. The front view which shows operation | movement of the embodiment. Sectional drawing which shows the operation | movement of the embodiment. The partially broken front view which shows the 2nd Embodiment of this invention. Sectional drawing which follows the DD line | wire of FIG. 7 which shows the same embodiment.

Explanation of symbols

1 ... Camshaft (driven rotor)
2 ... Housing (drive rotating body)
3. Timing sprocket (drive rotor)
4 ... Assembly angle adjusting mechanism 11a, 11b ... Guide groove (radial direction guide)
14a, 14a ... movable operation members 16a, 16b ... link arms (links)
26 ... ridge (meshing part)
27 ... Guide plate 28 ... Spring spring (spring member)
29 ... Electromagnet 32 ... Spiral guide wall (spiral guide)
34 ... Arc groove (stopper mechanism)
35 ... Stopper pin (stopper mechanism)
38 ... Lubricating oil supply path

Claims (2)

A drive rotor that is driven to rotate by the crankshaft of the engine;
A driven rotating body composed of a camshaft or a separate member coupled to the camshaft;
A guide plate having a guide whose diameter is reduced in the rotation direction;
The guide is engaged with the guide and is guided in the radial direction by a radial guide provided on the drive rotator, and the guide plate is rotated relative to the drive rotator and the driven rotator, thereby the guide. A movable operating member that moves inward or radially outward of the plate;
Assembling the drive rotator and the driven rotator by moving the movable operation member in the inner direction or the outer direction, having a link that connects the movable operation member with a portion separated by a predetermined distance from the center of the driven rotator. Assembly angle adjustment mechanism to change the angle;
With
A valve timing control device for an internal combustion engine, wherein the relative rotation phase between the crankshaft and the camshaft is variably controlled by rotating the guide plate relative to the drive rotator in accordance with an engine operating condition. A drive rotor that is driven to rotate by the crankshaft of the engine;
A driven rotating body composed of a camshaft or a separate member coupled to the camshaft;
A guide plate having a spiral guide;
Rutotomoni is guided by the spiral guide, the guided radially by the radial guide portion provided on the driving rotary member, by relative rotation of the guide plate relative to the drive rotor and the driven rotor, A movable operation member that moves in a radially inner direction or a radially outer direction of the guide plate;
Assembling the drive rotator and the driven rotator by moving the movable operation member in the inner direction or the outer direction, having a link that connects the movable operation member with a portion separated by a predetermined distance from the center of the driven rotator. Assembly angle adjustment mechanism to change the angle;
A valve timing control apparatus for an internal combustion engine, comprising:

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