JP2014055586A - Valve timing control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve timing control device of an internal combustion engine configured to be able to suppress wear of a torsion spring due to coil-to-coil contact even in the presence of the occurrence of the coil-to-coil contact of the torsion spring.SOLUTION: In the valve timing control device employing a helical torsion spring 30 attached at one end to a vane rotor 10 and attached at the other end to a housing 20, for applying biasing force to the vane rotor 10 toward a direction in which the vane rotor 10 is rotated relative to the housing 20, at least adjacent coils of the torsion spring being brought into contact with each other at a part of the torsion spring in a circumferential direction under a state where the biasing force is applied to the vane rotor 10, a back-pressure relief passage 40 is configured to discharge working fluid in a back-pressure chamber 36 of a lock mechanism 31. The back-pressure relief passage 40 is provided at a position that goes across a region where the coil-to-coil contact of the torsion spring 30 occurs when the vane rotor 10 rotates relative to the housing 20 at the maximum angle.

Description

  The present invention relates to a valve timing control device that controls opening and closing timings of an intake valve and an exhaust valve in an internal combustion engine according to an operating state.

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

  That is, in this valve timing control device, a torsion spring is interposed between the housing and the vane rotor, so that the reaction force of the valve spring (the rotational phase of the camshaft is generated by the biasing force of the torsion spring). This can counteract the force to be delayed), thereby improving the operability and responsiveness of the device.

JP 2005-325749 A

  However, with respect to the torsion spring, when an urging force is applied, the space between the spring lines in a part of the circumferential direction is narrowed so that the torsion spring is tilted with respect to the axis, and the spring line on the opposite side in the radial direction (180 degree opposite side) It will be deformed so as to widen the gap. As a result, the conventional valve timing device has a problem that the spring is worn by contact between the spring lines.

  The present invention has been devised in view of the actual situation of the conventional valve timing control device, and is capable of suppressing wear caused by the contact even if a line-to-line contact occurs in the torsion spring. The purpose is to provide.

  The invention described in claim 1 is a torsion coil spring, in which one end is fixed to the vane rotor and the other end is fixed to the housing, and a biasing force is applied to the housing in the direction of relative rotation of the vane rotor. In a state where the urging force is applied, a torsion spring in which at least a part of the lines in the circumferential direction is in contact with the back pressure chamber in which the urging member related to the lock mechanism of the vane rotor is disposed communicates with the outside of the housing. A back pressure relief passage that opens toward the torsion spring, and the back pressure relief passage makes contact between the lines of the torsion spring when the vane rotor rotates relative to the housing at a maximum angle. It is provided in the position which crosses the site | part to do.

  In the invention according to claim 2 of the present application, in particular, one end is fixed to the driven rotator and the other end is fixed to the drive rotator, and the urging force is applied in the direction of rotating the driven rotator relative to the drive rotator. A torsion coil spring to be actuated, in a state where the urging force is acting, a torsion spring in which a part of the circumferential line contacts, a spring guide provided on the outer peripheral side of the torsion spring, and a vane rotor A back pressure relief passage that communicates the back pressure chamber in which the biasing member related to the lock mechanism is disposed and the inner peripheral portion of the spring guide, and the back pressure relief passage is configured such that the driven rotor is driven by the driven rotor. When the relative rotation is performed at the maximum angle, the outer peripheral portion of the torsion spring is provided at a position crossing the portion where the outer peripheral portion of the spring guide contacts the innermost surface of the spring guide most strongly.

  The invention described in claim 3 is a torsion coil spring, in which one end is fixed to the vane rotor and the other end is fixed to the housing, and a biasing force is applied to the housing in the direction of relative rotation of the vane rotor. In a state where the urging force is applied, at least a part of the circumferential line is in contact with the torsion spring, the back pressure chamber in which the urging member related to the lock mechanism of the vane rotor is disposed, and the outside of the housing communicate with each other. A back pressure relief passage that is open toward the torsion spring, and the back pressure relief passage is opposite to the torsion direction of the torsion spring from a position where the other end of the torsion spring is fixed. It is characterized by being provided at a position crossing a position rotated 90 degrees in the direction.

  According to the first to third aspects of the present invention, the lubricating oil guided from the back pressure relief passage allows lubrication of the line-to-line contact in the torsion spring, and the torsion spring wears due to the line-to-line contact. Served for suppression.

It is a disassembled perspective view of the valve timing control apparatus which concerns on this invention. It is a front view of the valve timing control device concerning the present invention. It is a longitudinal cross-sectional view of the valve timing control apparatus shown in FIG. It is a figure which shows the internal structure of the valve timing control apparatus shown in FIG. 2, Comprising: It is the principal figure showing the state controlled to the advance side. It is a figure which shows the internal structure of the valve timing control apparatus shown in FIG. 2, Comprising: It is the principal figure showing the state controlled to the retard side. It is a principal part enlarged view of the locking mechanism shown in FIG. 4A and 4B are views showing a torsion spring alone shown in FIG. 3, in which FIG. 4A is a front view of the torsion spring, and FIG. 4B is a cross-sectional view taken along line AA in FIG. It is a principal part enlarged view of FIG. 3 which shows the assembly | attachment state of a torsion spring. FIGS. 4A and 4B are views for explaining the assembly of the torsion spring shown in FIG. 3, in which FIG. 3A is a perspective view of the valve timing control device before assembly of the torsion spring, and FIG.

  Hereinafter, an embodiment of a valve timing control device for an internal combustion engine according to the present invention will be described with reference to the drawings.

  That is, as shown in FIG. 3, this valve timing control device is interposed between a sprocket 1 that is rotationally driven by the rotational force of the crankshaft and a camshaft 2 that is provided to be rotatable relative to the sprocket 1. And the relative rotation phase of the both 1 and 2 is converted by controlling the operation through a predetermined hydraulic supply / discharge means 4.

  Specifically, as shown in FIGS. 3 to 5, a plurality of (four in this embodiment) are provided on the outer periphery of a cylindrical rotor body 15 fixed to one end of the camshaft 2 so as to be integrally rotatable. The vane rotor 10 formed by projecting the vanes 11 to 14 and the sprocket 1 are provided integrally with the vane rotor 10 so as to be relatively rotatable on the outer peripheral side of the vane rotor 10. A plurality of (four in this embodiment) shoes 21 to 24 corresponding to the vanes 11 to 14 on the inner peripheral side, and a housing 20 that is a substantially cylindrical drive rotating body, Hydraulic pressure is selectively supplied from the hydraulic supply / discharge means 4 to the retard chamber Re and the advance chamber Ad which are a pair of hydraulic chambers formed between the vanes 11 to 14 and the shoes 21 to 24. Actuated control by being It is.

  As shown in FIGS. 1 to 3, between the vane rotor 10 and the housing 20, one end 30 a is fixed to the vane rotor 10 and the other end 30 b is fixed to the housing 20. A torsion spring 30 that urges toward the advance side is interposed, and the camshaft 2 is moved immediately before the engine is stopped by the urging force of the torsion spring 30 so that no hydraulic pressure acts on any of the hydraulic chambers Ad and Re. The vane rotor 10 is biased to the advance side against a so-called alternating torque corresponding to the rotational force transmitted in the retard direction through the angle. In the present embodiment, the torsion spring 30 is formed by winding a rectangular wire having a substantially rectangular longitudinal section as shown in FIG. 7B, specifically a rectangular shape having a long side in the radial direction. I am using something. By adopting such a specification, the axial length of the torsion spring 30 can be reduced. As a result, the axial dimension of the apparatus can be reduced.

  The vane rotor 10 is externally fitted to one end portion of the camshaft 2 through a fitting portion 15a drilled on the inner end side (the side facing the camshaft 2) of the rotor body 15, and is formed to penetrate therethrough. The camshaft 2 is fastened to the camshaft 2 with a cam bolt 5 inserted through the insertion hole 15b. With this configuration, the vane rotor 10 that rotates synchronously with the camshaft 2 rotates relative to the housing 20 that rotates synchronously with the crankshaft, so that the rotational phase of the camshaft 2 with respect to the crankshaft changes. The opening / closing timing is changed.

  Here, as shown in FIGS. 3 to 5, oil passages described later are formed in the camshaft 2 at circumferential positions adjacent to the base ends of the vanes 11 to 14 in the vane rotor 10. A plurality of (four in the present embodiment) communication holes 16 communicating the first and second advance chambers 51 and the respective advance chambers Ad are formed in the radial direction. As a result, the hydraulic fluid guided from the hydraulic supply / discharge means 4 through the camshaft 2 (oil passages 51 and 52 described later) through the communication holes 16 is introduced into the advance chambers Ad. ing.

  As shown in FIGS. 1 to 5, the outer end of the rotor body 15 (the end facing the front plate 26 described later) is used for seating the cam bolt 5 in the outer peripheral area of the insertion hole 15 b. A flat bolt seating portion 17 is provided, and a spring seating portion 18, which is a circular groove provided for seating on the one end portion 30 a side of the torsion spring 30, is formed in the outer peripheral area of the bolt seating portion 17. The bolt seating portion 17 is set to a size close to the inner diameter, the outer diameter of which is slightly smaller than the inner diameter of the spring portion 30c that is a winding portion of the torsion spring 30, and the spring is attached to the outer peripheral portion of the spring. The part 30c is configured to fit. At this time, a predetermined chamfered portion 17 a having a longitudinal arc shape or a conical taper shape is continuously provided along the circumferential direction on the outer peripheral edge of the end of the bolt seating portion 17. It is possible to suppress the hooking of the axial movement of the spring portion 30c during the torque action.

  Further, a first locking portion 19 for locking and fixing the one end portion 30 a of the torsion spring 30 is provided on the end surface of the bolt seating portion 17 along the radial direction so as to open to the end surface of the bolt seating portion 17. Notches are formed. The first locking portion 19 is formed to penetrate the spring seat portion 18 and the insertion hole 15b so as to communicate with the spring seat portion 18 without a step, and one end portion 30a of the torsion spring 30 is connected to the bolt seat portion. It is locked and fixed in a form bent from the outer peripheral side of 17 to the center side. And in this 1st latching | locking part 19, the head part 5a of the cam volt | bolt 5 fastened by the camshaft 2 via the said insertion hole 15b superimposes in an axial direction so that the axial direction opening may be substantially obstruct | occluded. The falling off of the one end portion 30a of the torsion spring 30 from the first locking portion 19 is prevented. In this way, by using an existing configuration such as the head 5a of the cam bolt 5, there is no need to separately provide a fixing member for fixing the one end 30a of the torsion spring 30, improving the assembly workability and cost of the apparatus. It will be used for reduction.

  Each of the vanes 11 to 14 is provided with a seal member S1 at the front end thereof along the thickness direction (the axial direction of the rotor body 15). By being in sliding contact with the surface, a space formed between the shoes 21 to 24 is separated by the pair of hydraulic chambers Ad and Re. In addition, only a predetermined vane 11 among these vanes 11 to 14 is set to have a larger circumferential width than the other vanes 12 to 14, and the adjacent shoes 21, when the vane rotor 10 is at the maximum relative rotation, By abutting with 24, further rotation of the vane rotor 10 is restricted. Further, inside the wide vane 11, a lock mechanism 31 for accommodating the phase of the vane rotor 10 when the engine is stopped, which will be described later, is accommodated.

  As shown in FIGS. 3 to 6, the locking mechanism 31 is slidably received in a pin receiving hole 34 formed so as to penetrate the wide vane 11 in the inner axial direction, and is formed in a rear plate 27 described later. A substantially cylindrical lock pin 32 that restricts relative movement between the vane rotor 10 and the housing 20 by engaging with an engagement hole 35 provided, and is interposed between the lock pin 32 and a front plate 26 described later. The spring 33 is mainly composed of a spring 33 that is a biasing member that biases the lock pin 32 toward the rear plate 27 described later.

  Specifically, the lock pin 32 is configured to have a step reduced diameter toward the tip end side, and the pin receiving hole 34 has a step reduced diameter toward the rear plate 27 described later. By configuring, the large diameter portion 32 a on the proximal end side of the lock pin 32 is the large diameter portion 34 a on the front side of the pin accommodation hole 34, and the small diameter portion 32 b on the distal end side of the lock pin 32 is the rear of the pin accommodation hole 34. The spring 33 is elastically mounted on the back pressure chamber 36 defined by the large-diameter portion 34a of the pin receiving hole 34 by the large-diameter portion 32a of the lock pin 32. Has been. Then, the hydraulic pressure of the retarded angle chamber Re is introduced into the engagement hole 35 through a communication groove 37 formed in the inner surface of the wide vane 11 (an end surface facing the rear plate 27 described later). The lock pin 32 enters and exits the engagement hole 35 based on the hydraulic pressure in the retard chamber Re.

  Further, a step portion 32c formed between both diameter portions 32a and 32b of the lock pin 32 and a step portion 34c formed between both diameter portions 34a and 34b of the pin accommodating hole 34 are axially interposed. An annular space 38 is formed, and the space 38 is configured to communicate with the advance chamber Ad through a through hole 39 that penetrates the wide vane 11 toward the advance chamber Ad. Has been. That is, by guiding the hydraulic pressure of the advance chamber Ad to the space 38 through the through hole 39, when the hydraulic pressure of the advance chamber Ad becomes higher than a predetermined level, the lock pin 32 is disengaged from the engagement hole 35 ( (Non-engaged) state can be maintained.

  Further, a communication groove 40 a for communicating the pin accommodation hole 34 and the spring seat portion 18 is formed in the outer surface of the wide vane 11 (the end surface facing the front plate 26 described later). That is, the opening of the communication groove 40a is closed by the front plate 26 described later, so that a slight gap between the outer peripheral surface of the large diameter portion 32a of the lock pin 32 and the inner peripheral surface of the large diameter portion 34a of the pin receiving hole 34 is obtained. A back pressure relief passage 40 is provided for discharging hydraulic oil leaked from the gap to the back pressure chamber 36 side. The back pressure relief passage 40 (communication groove 40a) is a portion where the windings contact with each other in the spring portion 30c of the torsion spring 30 when the vane rotor 10 rotates relative to the housing 20 at the maximum (maximum angle). (Hereinafter referred to as the “line contact portion”.) The hydraulic fluid that is provided at a circumferential position across T (see FIG. 8) and is discharged through the back pressure relief passage 40 is the line contact portion described above. It extends to T.

  Here, the circumferential position across the line-to-line contact portion T of the spring portion 30c specifically refers to the torsion direction of the torsion spring 30 from the fixed position of the other end portion 30b of the torsion spring 30 (the torsion spring 30 of the torsion spring 30). It refers to a circumferential position that crosses a position rotated approximately 90 degrees in a direction opposite to the direction in which the urging force acts (see FIGS. 4 and 5). This is because a rotational force is applied to the torsion spring 30 with the other end 30b as an axis, and the urging force of the torsion spring 30 acts from the fixed position of the other end 30b by this rotational force. This is based on the fact that the position rotated approximately 90 degrees in the opposite direction becomes the contact portion T between the lines.

  As for the arrangement of the back pressure relief passage 40, the outer periphery of the spring portion 30 c and the inner periphery of the spring guide 41 are the most due to the tilt generated in the spring portion 30 c when the vane rotor 10 rotates relative to the housing 20 by the maximum angle. It is desirable to provide it at a circumferential position that crosses a portion that makes strong contact (see FIG. 8). With such a configuration, the hydraulic oil discharged through the back pressure relief passage 40 is discharged from the spring portion 30c and the spring guide. It is possible to extend to the contact portion with 41.

  As shown in FIGS. 1 to 5, the housing 20 includes a substantially cylindrical housing main body 25 in which the plurality of shoes 21 to 24 project on the inner peripheral side, and front and rear opening ends of the housing main body 25. The front plate 26 and the rear plate 27 are closed, and the front plate 26 and the rear plate 27 are integrally coupled to the housing body 25 in the form of being fastened together via the four bolts 6 in the axial direction.

  Each of the shoes 21 to 24 is also provided with a sealing member S2 along the thickness direction at the tip thereof, as shown in FIGS. 4 and 5, like the vanes 11 to 14. These seal members S2 are in sliding contact with the outer peripheral surface of the rotor main body 15 of the vane rotor 10, whereby the hydraulic chambers Ad, Re as described above are separated between the shoes 21-24. In addition, predetermined build-up portions 28 and 28 project on the proximal end side of the pair of shoes 21 and 24 adjacent to the wide vane 11 among the shoes 21 to 24 on one side in the circumferential direction. In the maximum relative rotation of the vane rotor 10, the hydraulic chambers Ad and Re are secured in the circumferential direction with the wide vane 11 while being in contact with the wide vane 11, so that The above rotation is regulated.

  The front plate 26 has a relatively thin disk shape as shown in FIGS. 1 to 3, and a cylindrical portion 43 configured to protrude outward is provided at the center thereof. The cam bolt 5 and the torsion spring 30 can be assembled from the outside through the inner peripheral hole 43a of the cylindrical portion 43 (see FIG. 9). Here, as shown in FIG. 8 in particular, the cylindrical portion 43 is set so that its inner diameter is substantially the same as the outer diameter of the spring seat portion 18 of the vane rotor 10, and a series of substantially smooth portions together with the spring seat portion 18. The spring guide 41 is formed by forming a cylindrical peripheral wall, and a series of spring accommodating portions 42 for accommodating the spring portion 30c of the torsion spring 30 are configured on the inner peripheral side of the spring guide 41. ing. With this configuration, the spring portion 30 c of the torsion spring 30 is accommodated in the spring accommodating portion 42 so as to be smoothly movable in the axial direction by the spring guide 41, and the spring portion 30 c is smoothly deformed when the torque acts on the torsion spring 30. Is secured.

  Further, as shown in FIGS. 1 and 2, the projecting end 43b of the cylindrical portion 43 is provided with a notch 44 formed by notching a part in the circumferential direction, and one side wall 44a thereof. A second locking portion 45 serving to lock and fix the other end portion 30b of the torsion spring 30 is cut out by cutting out a part of the base end side along the circumferential direction. As described above, the second locking portion 45 is formed in a groove shape that opens to the protruding end portion 43b of the cylindrical portion 43, so that the torsion spring 30 passes through the inner peripheral hole 43a of the cylindrical portion 43 as shown in FIG. As a result, when assembling the apparatus, after mounting the torsion spring 30, other parts are rotated while the housing 20 and the vane rotor 10 are relatively rotated against the urging force of the torsion spring 30. As a result, complicated assembly work such as assembly is avoided, and good productivity of the apparatus is ensured.

  Here, as shown in FIG. 2, the notch portion 44 has both side walls 44 a and 44 b substantially parallel to each other, and the end of the second locking portion 45 to which the other end portion 30 b of the torsion spring 30 is locked. With respect to the straight line L2 formed by extending the other side wall 44b of the notch 44 to the inner peripheral side so that the straight line L1 formed by extending the wall 45a to the inner peripheral side passes near the center C of the cylindrical portion 43. It is provided so as to be close to the center C of the cylindrical portion 43. Specifically, the cutout portion 44 is located at a position where the end wall 45a of the second locking portion 45 is offset toward the line L0 passing through the center C of the cylindrical portion 43 with respect to the other side wall 44b of the cutout portion 44. It is formed by being punched in the radial direction by a punch, and is configured such that the other end wall 44b has an obtuse angle (see θ in FIG. 2) with respect to a tangent line L3 related to the inner peripheral surface of the cylindrical portion 43. Yes.

  Further, when the second locking portion 45 is provided, a groove shape is formed by notching only the base end side portion of the one side wall 44a of the notch portion 44, and the projecting end portion 43b at the front end side of the notch portion 44 is formed. Since the circumferential width W1 is configured to be stepped narrower with respect to the circumferential width W2 on the proximal end side of the protruding end portion 43b, the axially outer side portion 45b of the second locking portion 45 is provided in addition to the torsion spring 30. It functions as a retaining portion for restricting the axial movement of the end portion 30b, and the retaining portion 45b regulates the falling of the torsion spring 30 so that the torsion spring 30 can be stably held. It has become.

  As shown in FIGS. 3 to 5, the rear plate 27 is formed in a substantially disc shape, and is formed integrally with the sprocket 1 in such a manner that the sprocket 1 is provided on the outer periphery thereof. An insertion hole 27a through which the camshaft 2 is inserted is formed through the center of the rear plate 27, and a female screw hole 27b into which the bolts 6 are screwed is formed in the outer peripheral area. . Further, a plurality of later-described retard angle side oil passages 51 formed inside the camshaft 2 and a plurality of retard angle chambers Re are respectively communicated with the peripheral edge portion of the insertion hole 26a on the inner side surface of the rear plate 27. The communication grooves 46 (four in this embodiment) are each notched along the radial direction. As a result, the hydraulic oil guided from the hydraulic supply / discharge means 4 through the camshaft 2 (oil passages 51 and 52 described later) through the communication grooves 46 is introduced into the retard chambers Re. ing.

  Further, the inner surface of the rear plate 27 is formed with an engagement hole 35 for restricting the rotation of the vane rotor 10 by engaging with the lock pin 32 when the vane rotor 10 is at the most advanced position. . That is, as shown in FIG. 6, the engagement hole 35 has a first hole portion 35 a on the near side larger in diameter than the outer diameter of the distal end portion of the lock pin 32, and a second hole portion on the back side. 35b is configured to have a step-reduced diameter that is smaller than the outer diameter of the tip of the lock pin 32, and the lock pin 32 is the first hole when the phase of the vane rotor 10 is in the most advanced angle state as described above. By engaging with the portion 35a, the relative rotation of the vane rotor 10 with respect to the housing 20 is restricted.

  Further, as shown in FIGS. 1, 4 and 5, the inner surface of the rear plate 27 is engaged with an engagement groove 47 formed in the outer peripheral portion of the housing body 25, thereby engaging the housing body. A positioning pin 48 is provided for positioning with the positioning pin 25, and the positioning pin 48 ensures a good engagement relationship between the lock pin 32 and the engagement hole 35 after the housing 20 is assembled by the bolts 6. It has come to be.

  As shown in FIG. 3, the hydraulic supply / discharge means 4 selectively supplies hydraulic pressure to the hydraulic chambers Ad and Re, or discharges hydraulic oil in the hydraulic chambers Ad and Re. The retard angle side oil passage 51 connected to each communication groove 46, the advance angle side oil passage 52 connected to each communication hole 16, and the oil passages 51, 52 on one side via a known electromagnetic valve 55. An oil pump 53 serving as a hydraulic pressure source for supplying hydraulic pressure and a drain passage 54 connected to the other oil passages 51 and 52 not connected to the oil pump 53 via the electromagnetic valve 55 are mainly configured. The solenoid valve 55 is a two-way switching valve, and selectively connects the oil passages 51, 52 to the oil pump 53 and the drain passage 54 by a control signal from an electronic controller (ECU) (not shown). Is switched to.

  Hereinafter, the effect of the valve timing control device for an internal combustion engine according to the present invention will be described with reference to FIGS.

  First, when the engine is started, as shown in FIGS. 3 and 4, the tip of the lock pin 32 is engaged with the engagement hole 35 (first hole 35a) in advance, so that the vane rotor 10 starts the engine. It is in a state of being held at an optimal predetermined advance position. For this reason, a good engine start by smooth cranking can be obtained by turning on the ignition.

  Subsequently, in a predetermined load range after the engine is started, the retard side oil passage 51 communicates with the oil pump 53 based on energization to the solenoid valve 55 from the electronic controller (not shown), and the advance side oil The passage 52 communicates with the drain passage 54. That is, the hydraulic oil discharged from the oil pump 53 flows into the retardation chamber Re through the retardation-side oil passage 51, whereby the retardation chamber Re becomes high pressure, while the hydraulic oil in the advance chamber Ad is The advance chamber Ad is reduced in pressure by being discharged to the oil pan 56 through the advance side oil passage 52 and the drain passage 54. Then, the hydraulic oil that has flowed into the retarded angle chamber Re flows into the engagement hole 35, whereby the lock pin 32 is detached from the engagement hole 35, and free rotation of the vane rotor 10 is ensured. It will be. As a result, as the volume of the retard chamber Re is increased based on the hydraulic pressure supply to the retard chamber Re, the vane rotor 10 rotates counterclockwise as shown in FIG. The relative rotational phase of the shaft 2 is converted to the retard side.

  On the other hand, when the engine shifts to another load region, the energization from the electronic controller (not shown) to the solenoid valve 55 is cut off, the advance side oil passage 52 communicates with the oil pump 53, and the retard angle. The side oil passage 51 communicates with the drain passage 54. That is, the hydraulic oil in the retarding chamber Re is discharged to the oil pan 56 through the retarding-side oil passage 51 and the drain passage 54, so that the retarding chamber Re becomes low pressure, while being discharged from the oil pump 53. The advanced hydraulic fluid flows into the advance chamber Ad through the advance side oil passage 52, whereby the advance chamber Ad becomes high pressure. Then, along with the hydraulic pressure supply to the advance chamber Ad, the hydraulic pressure in the advance chamber Ad is supplied to the space portion 38 through the through hole 39, and based on the oil pressure in the space portion 38. The state where the lock pin 32 is disengaged from the engagement hole 35 is maintained. As a result, as the volume of the advance chamber Ad increases based on the hydraulic pressure supply to the advance chamber Ad, the vane rotor 10 rotates clockwise as shown in FIG. The relative rotational phase of 2 is converted to the advance side.

  Immediately before the engine is stopped, the hydraulic pressure supply to the hydraulic chambers Ad and Re is stopped, and the vane rotor 10 tries to rotate relative to the retard side by the alternating torque acting on the camshaft 2. When the urging force of the torsion spring 30 acts, the vane rotor 10 rotates relative to the advance side against the alternating torque as shown in FIG. Then, when the lock pin 32 moves forward based on the urging force of the spring 33, the tip of the lock pin 32 is engaged with the engagement hole 35 (first hole 35a), and the vane rotor 10 is It is held at a predetermined advance position.

  As described above, in the valve timing control device, free rotation of the vane rotor 10 is ensured or maintained by applying hydraulic pressure to the engagement hole 35 or the space 38. The hydraulic oil supplied to the hole 35 and the space 38 is not limited to the back pressure chamber 36 through a slight radial gap formed between the outer peripheral surface of the lock pin 32 and the inner peripheral surface of the pin accommodation hole 34. Leaking (inflowing) and discharged from the back pressure chamber 36 through the back pressure relief passage 40 to the spring accommodating portion 42.

  Then, since the back pressure relief passage 40 is provided at a circumferential position so as to cross the line contact portion T of the torsion spring 30 when the vane rotor 10 is relatively rotated as described above, the back pressure relief passage is provided. The hydraulic oil discharged through 40 acts on the line-to-line contact part T, and the friction between the windings of the line-to-line contact part T is lubricated by this hydraulic oil, and wear of the line-to-line contact part T is suppressed. can do. In particular, when the above-described rectangular wire is used as the torsion spring 30 as in the present embodiment, when a rotational load (torque) is applied to the spring 30, the spring portion 30 c is tilted in the axial direction. Since this makes it easier for the contact between the lines to occur, lubrication with the hydraulic oil becomes more effective. In the present embodiment in which the torsion spring 30 having a substantially rectangular longitudinal section with the long side in the radial direction is employed, the inclination of the spring portion 30c in the axial direction is further increased. Lubrication due to is more effective.

  Further, due to the tilt generated in the spring portion 30 c, the line contact portion T comes into pressure contact with the inner peripheral surface of the spring guide 41, but the back pressure relief passage 40 opens to the inner peripheral surface of the spring guide 41. Thus, the hydraulic oil discharged from the back pressure relief passage 40 effectively acts on the pressure contact portion P, and effective lubrication can be achieved for friction in the pressure contact state.

  As described above, according to the valve timing control device for an internal combustion engine according to the present invention, the contact between the lines or the pressure contact with the spring guide 41 is caused by the tilt of the spring portion 30c based on the torque action when the vane rotor 10 is relatively rotated. A circumferential position across the part, that is, a position rotated by approximately 90 degrees from the fixed position of the other end 30b of the torsion spring 30 in the direction opposite to the twisting direction of the torsion spring 30 (the direction in which the urging force of the torsion spring 30 acts). By providing the back pressure relief passage 40 in the circumferential position across the center, the pressure contact portion P between the line contact portion T and the spring guide 41 is lubricated with the hydraulic oil guided from the back pressure relief passage 40. As a result, the spring portion 30c (due to friction in the line contact or pressure contact state) Is subjected to suppression of wear of the line).

  Further, since the back pressure relief passage 40 is constituted by the communication groove 40a provided on the outer side surface of the wide vane 11 of the vane rotor 10, the back pressure relief passage 40 is constituted by a hole as compared with the case where the back pressure relief passage 40 is constituted by a hole. It can be formed easily, and good productivity of the apparatus is ensured.

  When the hydraulic oil is guided to the spring accommodating portion 42 by the back pressure relief passage 40, a configuration in which the hydraulic oil is introduced into the space portion 38 adjacent to the back pressure chamber 36 as in the present embodiment is employed. The hydraulic oil leaks through the radial gap between the lock pin 32 and the pin accommodating hole 34 more easily, so that a sufficient amount of hydraulic oil can be supplied through the back pressure relief passage 40. Good lubrication for the line contact portion T and the like can be obtained.

  The present invention is not limited to the configuration of the above-described embodiment. For example, the back pressure relief passage 40 may be configured as long as the back pressure chamber 36 and the spring accommodating portion 42 are communicated with each other. The specific configuration can be arbitrarily changed, for example, by providing a through-hole inside.

  In addition, the specific configurations of parts or members that do not affect the operational effects of the present invention, such as the housing 20, the vane rotor 10, and the hydraulic supply / discharge means 4, can be changed as appropriate according to the specifications of the apparatus.

  Hereinafter, technical ideas grasped from the embodiment other than those described in the claims will be described.

(A) In the valve timing control device for an internal combustion engine according to claim 1,
A valve timing control device for an internal combustion engine, wherein a spring guide is provided on an outer peripheral side of the torsion spring.

  In the case of such a configuration, the lubricating oil guided from the back pressure relief passage enables lubrication of the contact (friction) between the torsion spring and the spring guide, thereby effectively suppressing wear on the torsion spring.

(B) In the valve timing control device for an internal combustion engine according to claim 1,
The housing includes a cylindrical housing body having a plurality of shoes projecting from the inner periphery thereof, a front plate that seals the distal end side of the housing body, and a rear plate that seals the camshaft side of the housing body. Composed of,
The valve timing control device for an internal combustion engine, wherein the spring guide includes a convex cylindrical portion formed on the front plate and a circular groove formed on the vane rotor.

(C) In the valve timing control device for an internal combustion engine according to (b),
The valve timing control device for an internal combustion engine, wherein the back pressure relief passage is a groove formed on a sliding surface of the vane rotor with the front plate.

  With this configuration, the back pressure relief passage can be easily formed as compared with the case where the back pressure relief passage is configured by a hole, and good productivity can be ensured.

(D) In the valve timing control device for an internal combustion engine according to claim 1,
The valve timing control device for an internal combustion engine, wherein the torsion spring has a substantially rectangular cross section.

  In such a configuration, since the inclination of the torsion spring during torque action is likely to be greater than when the line has a circular cross section, the lubricating effect through the back pressure relief passage becomes more prominent.

(E) In the valve timing control device for an internal combustion engine according to (d),
A valve timing control device for an internal combustion engine, wherein a cross section of a line of the torsion spring is set to be a rectangle having a long side in a radial direction of the torsion spring.

  In such a configuration, since the tilt of the torsion spring at the time of torque action becomes larger, the lubricating effect through the back pressure relief passage becomes more effective.

(F) In the valve timing control device for an internal combustion engine according to claim 1,
The back pressure relief passage is positioned on the advance side with respect to a portion where the lines of the torsion springs are in contact with each other when the lock mechanism is locked by the lock recess. A valve timing control device for an internal combustion engine.

(G) In the valve timing control device for an internal combustion engine according to claim 1,
The lock member is a pin having a step portion between a large diameter portion and a small diameter portion, and is configured such that hydraulic pressure acts on at least the step portion. apparatus.

  According to such a configuration, the hydraulic oil acts on the stepped portion, so that the lubricating oil leaks easily through the back pressure relief passage, and a good lubricating effect through the back pressure relief passage can be obtained.

(H) In the valve timing control device for an internal combustion engine according to (g),
The valve timing control device for an internal combustion engine, wherein the lock member is configured such that different hydraulic pressures act on the large diameter portion and the small diameter portion.

DESCRIPTION OF SYMBOLS 10 ... Vane rotor 11-14 ... Vane 15 ... Rotor main body 20 ... Housing 21-24 ... Shoe 30 ... Torsion spring 31 ... Lock mechanism 32 ... Lock pin (lock member)
33 ... Spring (biasing member)
34 ... Pin receiving hole (Cylinder component hole)
35 ... engagement hole (lock recess)
36 ... Back pressure chamber 40 ... Back pressure relief passage Ad ... Advance chamber (advance chamber)
Re ... retarded angle chamber (retarded working chamber)

Claims (3)

A housing in which a rotational force is transmitted from the crankshaft and a plurality of working chambers are formed by projecting a plurality of shoes on the inner peripheral side;
A rotor fixed to the camshaft, and a plurality of vanes that project from the outer periphery of the rotor and separate the plurality of working chambers into an advance working chamber and a retard working chamber. The hydraulic pressure is supplied to the angular working chamber and the hydraulic oil in the retard working chamber is discharged to advance the housing, while the hydraulic pressure is supplied to the retard working chamber and the hydraulic working chamber is provided. A vane rotor configured to be retarded with respect to the housing by discharging hydraulic oil, and having a cylinder-constituting hole penetratingly formed in at least one of the plurality of vanes extending in a rotation axis direction;
A lock member slidably provided in the cylinder constituting hole, and a biasing member that biases the lock member in a direction in which the lock member protrudes from the vane rotor, and applies hydraulic pressure to the lock member. A lock mechanism configured to withdraw the lock member against the biasing force of the biasing member,
A lock recess provided at a position facing the lock member of the housing, the lock member protruding and inserted to restrict relative rotation between the housing and the vane rotor;
A torsion coil spring having one end fixed to the vane rotor and the other end fixed to the housing, and applying a biasing force to the housing in a direction of rotating the vane rotor relative to the housing, the biasing force acting A torsion spring in which at least some of the circumferential lines are in contact with each other,
A passage communicating the back pressure chamber in which the urging member is disposed and the outside of the housing, and a back pressure relief passage formed to open toward the torsion spring,
The valve timing of the internal combustion engine, wherein the back pressure relief passage is provided at a position crossing a portion where the line of the torsion spring contacts when the vane rotor rotates relative to the housing at a maximum angle. Control device. A driving rotating body to which rotational force is transmitted from the crankshaft;
A driven rotor that is fixed to the camshaft and is advanced or retarded with respect to the drive rotor by supplying and discharging hydraulic oil, and provided with a cylinder constituting hole extending in the direction of the rotation axis;
A lock member slidably provided in the cylinder constituting hole, and an urging member for urging the lock member in a direction in which the lock member protrudes from the driven rotating body, and hydraulic pressure is applied to the lock member. A lock mechanism configured to retract the lock member against the biasing force of the biasing member by acting;
A lock recess that is provided at a position facing the lock member in the drive rotator, and that restricts relative rotation between the drive rotator and the driven rotator when the lock member protrudes and is inserted;
A torsion coil spring having one end fixed to the driven rotator and the other end fixed to the drive rotator, and applying a biasing force to the drive rotator in a direction to relatively rotate the driven rotator. , A torsion spring in which a part of the lines in the circumferential direction are in contact with each other when the urging force is applied;
A spring guide provided on the outer peripheral side of the torsion spring;
A back pressure relief passage that communicates the back pressure chamber in which the biasing member is disposed and the inner peripheral portion of the spring guide;
The back pressure relief passage is located at a position where the outer peripheral portion of the torsion spring makes the strongest contact with the inner peripheral surface of the spring guide when the driven rotor rotates relative to the drive rotor at a maximum angle. A valve timing control apparatus for an internal combustion engine, which is provided in the engine. A housing in which a rotational force is transmitted from the crankshaft and a plurality of working chambers are formed by projecting a plurality of shoes on the inner peripheral side;
A rotor fixed to the camshaft, and a plurality of vanes that divide the plurality of working chambers into an advance working chamber and a retard working chamber, and supply hydraulic pressure to the advance working chamber and The hydraulic fluid in the angular working chamber is advanced to advance the housing, while the hydraulic pressure is supplied to the retarding hydraulic chamber and the hydraulic fluid in the advanced hydraulic chamber is discharged to the housing. A vane rotor configured to be operated at a retarded angle and having a cylinder-constituting hole penetratingly formed in at least one of the plurality of vanes extending in the rotation axis direction;
A lock member slidably provided in the cylinder constituting hole, and a biasing member that biases the lock member in a direction in which the lock member protrudes from the vane rotor, and applies hydraulic pressure to the lock member. A lock mechanism configured to withdraw the lock member against the biasing force of the biasing member,
A lock recess provided at a position facing the lock member of the housing, the lock member protruding and inserted to restrict relative rotation between the housing and the vane rotor;
A torsion coil spring having one end fixed to the vane rotor and the other end fixed to the housing, and applying a biasing force to the housing in a direction to relatively rotate the vane rotor, wherein the biasing force is acting A torsion spring in which at least a part of the lines in the circumferential direction are in contact with each other;
A passage communicating the back pressure chamber in which the urging member is disposed and the outside of the housing, and a back pressure relief passage formed to open toward the torsion spring,
The internal combustion engine, wherein the back pressure relief passage is provided at a position crossing a position rotated 90 degrees from a position where the other end of the torsion spring is fixed to a direction opposite to the twisting direction of the torsion spring. Valve timing control device.

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