JP2012036791A - Variable valve system of internal combustion engine, and method for adjusting holding state of valve timing thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of tap tone caused by an excessive difference between an advance limiting period and a retard limiting period when advance and retard of a timing valve are limited, respectively, in holding the valve timing in a specified period between the advance limiting period and the retard limiting period.SOLUTION: A variable valve mechanism includes a holding mechanism 40 which separately includes an advance limiting mechanism 50 limiting a relative rotation on an advanced side of a vane rotor to a housing 22; and a retard limiting mechanism 70 which limiting a relative rotation on a retard side. The holding mechanism also holds a relative rotation phase in an intermediate phase by the cooperation of the limiting mechanisms. The variable valve mechanism further includes a phase adjusting plate 25 which is relatively and rotatable to a sprocket 21. While a relative rotation is limited by the advance limiting mechanism 50, the phase adjusting plate 25 is relatively rotated so as to be limited a reverse relative rotation to fix the phase adjusting plate 25 on the sprocket 21, and thereby the variable valve mechanism adjusts a state that the relative rotation phase is held in an intermediate phase.

Description

  The present invention relates to a variable valve operating apparatus for an internal combustion engine including a variable mechanism that changes a valve timing and a holding mechanism that holds the valve timing at a specific time, and a method for adjusting a holding state of the valve timing.

As a device mounted on an internal combustion engine, a variable valve device having a variable valve mechanism that changes valve timings of intake valves and exhaust valves driven to open and close by a camshaft is known.
FIG. 17 is a cross-sectional view showing a variable valve mechanism 200 of such a variable valve apparatus. The variable valve mechanism 200 includes two rotating bodies that rotate around the same rotation axis, such as a vane rotor 210 that rotates in synchronization with the camshaft 300 and a housing 220 that rotates in synchronization with the crankshaft 310. The vane rotor 210 is provided with two vanes 211 extending outward in the radial direction. The housing 220 is provided with two recesses 221 for receiving the vanes 211. The recess 221 defines two oil chambers to which hydraulic oil is supplied by vanes 211 accommodated therein. Among these, the oil chamber located on the opposite side of the vane 211 to the rotation direction of the cam shaft 300 generates an advance chamber 222 that generates hydraulic pressure for rotating the vane rotor 210 relative to the housing 220 in the rotation direction of the cam shaft 300. It has become. In addition, the oil chamber located on the opposite side of the advance chamber 222 across the vane 211 in the recess 221 generates a hydraulic pressure for causing the vane rotor 210 to rotate relative to the housing 220 in the counter-rotating direction of the camshaft 300. It is a corner chamber 223.

  Then, according to the variable valve operating apparatus provided with such a variable valve mechanism 200, the vane rotor 210 is moved to the housing 220 by changing the hydraulic pressure of the advance chamber 222 and the hydraulic pressure of the retard chamber 223 acting on each vane 211. The relative rotation phase of the camshaft 300 can be changed with respect to the crankshaft 310 by rotating it relative to the crankshaft 310, and the valve timing can be changed to a time according to the engine operating state at that time.

  By the way, since the hydraulic oil is supplied to the advance chamber 222 and the retard chamber 223 through an engine-driven hydraulic pump driven by the crankshaft 310, the engine is started after a long period of time has elapsed after the engine is stopped. When the hydraulic pressure of the advance chamber 222 or the retard chamber 223 is low, the vane 211 cannot be held by the hydraulic pressure of the oil chambers 222 and 223, and the camshaft 300 may turn unnecessarily. is there. If such rotation occurs, the valve timing at the time of starting the engine becomes unstable, and for example, the startability of the engine may be deteriorated. Therefore, in the variable valve operating apparatus, as described in Patent Document 1, when the hydraulic pressure of the oil chambers 222 and 223 cannot be sufficiently secured, in order to avoid such unstable valve timing, A holding mechanism is provided that can mechanically hold the valve timing at a time suitable for starting the engine.

JP 2002-357105 A

  In such a holding mechanism, a valve timing is controlled by, for example, an engine by inserting a limiting member for limiting the advance angle and delay angle of the valve timing, such as a pin provided on the vane rotor, into a recess provided in the housing. It is held at a specific time suitable for starting. However, in such a configuration, an alternating force based on the reaction force of the valve spring, the rotational force transmitted from the crankshaft, etc. always acts between the outer peripheral surface of the limiting member and the inner peripheral surface of the recess. Yes. For this reason, there is a concern that it takes more time than necessary to remove the restriction member from the recess and release the holding of the valve timing by the holding mechanism.

  Therefore, as shown in FIG. 18, as the holding mechanism 230, an advance angle limiting mechanism 240 that limits the advance angle of the valve timing and a delay angle limit mechanism 250 that limits the delay angle are separately provided, and by their cooperation, It is conceivable to employ a configuration in which the valve timing is held at a specific time. Specifically, the advance angle limiting mechanism 240 engages the advance angle limiting member 241 provided on the vane 211 and the advance angle limiting recess 242 provided on the housing 220, thereby causing the vane rotor 210 to be relatively relative to the housing 220. The valve timing is advanced by restricting the rotation. On the other hand, the retard angle limiting mechanism 250 regulates the relative rotation of the vane rotor 210 with respect to the housing 220 by engaging the retard angle limiting member 251 provided in the vane 211 with the retard angle limiting recess 252 provided in the housing 220. To limit the valve timing delay. In the holding mechanism 230, the relative rotational phase of the vane rotor 210 with respect to the housing 220 when the advance angle of the valve timing is limited matches the relative rotational phase when the retard angle of the valve timing is limited. The valve timing is held at a specific time.

  By adopting such a configuration, a pressing force acts between the advance angle limiting member 241 and the advance angle limiting recess 242 when the housing 220 and the vane rotor 210 rotate relative to each other so that the valve timing is advanced. These pressing forces do not act when they rotate relative to each other so that the valve timing is retarded. Similarly, between the retard angle limiting member 251 and the retard angle limiting recess 252, although the pressing force acts when the housing 220 and the vane rotor 210 are relatively rotated so that the valve timing is retarded, the valve timing is advanced. Thus, such pressing force does not act when they rotate relative to each other. Thus, a pressing force is intermittently applied between the advance angle limiting member 241 and the advance angle limiting recess 242 and between the retard angle limiting member 251 and the retard angle limiting recess 252. Therefore, when such pressing force is not acting, the restricting members 241 and 251 can be easily removed from the restricting recesses 242 and 252 so that the valve timing can be quickly released. Become.

  However, in such a holding mechanism 230, the minimum distance in the circumferential direction of the advance limit member 241 and the retard limit member 251 (due to the existence of dimensional errors and assembly errors of the members constituting the mechanism 230). 18: The distance L1 between the limiting members may not match the shortest distance in the circumferential direction of the advance angle limiting recess 242 and the retard angle limiting recess 252 (FIG. 18: engagement distance L2). When the distance L1 between the restricting members is shorter than the distance L2 between the engaging members, one of the restricting members 241 and 251 cannot be fitted into the corresponding restricting recesses 242 and 252, and therefore the distance L1 between the restricting members is set to the distance L2 between the engaging members. Set slightly larger than. In other words, it is premised that each of the limiting members 241 and 251 can be fitted into the corresponding limiting recesses 242 and 252 with an appropriate clearance.

  However, since an alternating torque is constantly acting on the camshaft 300 (see FIG. 17) due to the reaction force of the valve spring or the like, if the clearance is excessively large, the advance angle limiting member 241 and the advance angle limiting recess are provided. The occurrence of hitting sound due to frequent repetition of the collision at the engagement portion with 242 and the collision at the engagement portion between the retardation limiting member 251 and the retardation limiting recess 252 becomes a problem.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an advance angle limiting mechanism that limits the advance angle of the valve timing and a retard angle that limits the delay angle in a variable valve operating apparatus that changes the valve timing. When holding at a specific time between the advance limit time when the advance angle of the valve timing is restricted and the retard limit time when the retard angle is restricted, the advance angle limit time and the retard angle limit time are provided. Avoiding an unnecessarily large difference between the time limit and the occurrence of such an excessive difference, and suppressing the occurrence of sound hitting, and also between the advance angle limit time and the retard angle limit time This is to adjust the holding state of the valve timing by adjusting the difference between them to an appropriate size.

In the following, means for achieving the above object and its effects are described.
(1) The invention described in claim 1 includes a first rotating body that rotates in synchronization with one of the crankshaft and the camshaft and a second rotating body that rotates in synchronization with the other, and includes both the rotating bodies. A variable valve mechanism that changes the valve timing of a valve that is driven to open and close by the camshaft by rotating around the same rotation axis, and restricting the advancement of the valve timing by restricting the relative rotation of the two rotating bodies And a retard restriction mechanism that restricts the delay of the valve timing by restricting the relative rotation of the two rotating bodies, and holds the valve timing at a specific time by the cooperation of these restriction mechanisms. A variable valve operating apparatus for an internal combustion engine comprising a holding mechanism, wherein the holding mechanism includes a phase adjusting member, and the phase adjusting member controls the valve timing by any one of the limiting mechanisms. And controlling the relative rotation phase of the two rotating bodies at the time of the regulation by rotating around the rotating shaft. To do.

  According to this configuration, due to the existence of dimensional errors and assembly errors of the members constituting each limiting mechanism, excessive relative rotation of both rotating bodies when the valve timing is held at a specific time by each limiting mechanism. Even if this occurs, both rotations when the relative rotation is restricted by the advance angle limiting mechanism or the retard angle limiting mechanism so that the relative rotation amount is reduced by rotating the phase adjusting member. The relative rotational phase of the body can be adjusted. In other words, the valve timing can be adjusted so that a difference larger than necessary does not occur between the advance limit time by the advance limit mechanism and the retard limit time by the retard limit mechanism. Therefore, even when the valve timing is held at a specific time, even if an alternating torque is applied to rotate both rotating bodies relative to each other due to the reaction force of the valve springs, the occurrence of hitting sound due to the alternating torque is suppressed. be able to.

  (2) The invention according to claim 2 is the variable valve operating apparatus for the internal combustion engine according to claim 1, wherein the first rotating body is spaced apart in the circumferential direction of the rotating shaft, and an advance angle limiting member and A retard limit member is provided, and the advance limit mechanism engages the advance limit member with the second rotating body to limit the advance timing of the valve timing, while the retard limit mechanism The retardation limiting member is engaged with the second rotating body to limit the retardation of the valve timing, and the phase adjusting member is assembled to the second rotating body as a part of the second rotating body. Relative rotation of the two rotating bodies when the valve timing becomes the specific time by rotating around the rotation axis and engaging either one of the limiting members in one direction. To be regulated by phase And effect.

  According to this configuration, for example, the retardation adjusting member of the retardation restriction mechanism is engaged with the second rotating body and the retardation of the valve timing is restricted, so that the phase adjusting member is rotated around the rotation axis. The valve timing can be maintained at a specific time by moving and engaging with the advance limit member of the advance side limit mechanism. Similarly, in a state where the advance angle limiting member of the advance angle limiting mechanism is engaged with the second rotating body and the advance timing of the valve timing is limited, the phase adjusting member is rotated around the rotation axis. By engaging this with the retard limit member of the retard limit mechanism, the valve timing can be maintained at a specific time. In other words, the relative rotation phase when regulating the relative rotation of both rotating bodies so that an excessive difference does not occur between the advance angle limit time by the advance angle limit mechanism and the retard angle limit time by the delay angle limit mechanism with respect to the valve timing. While adjusting the valve timing, the valve timing can be maintained at a specific time. Thus, the invention described in claim 1 can be embodied with the configuration described in claim 2.

  (3) According to a third aspect of the present invention, in the variable valve operating apparatus for an internal combustion engine according to the second aspect, the holding mechanism includes a through hole for restricting the advance angle at a position spaced apart in the circumferential direction of the rotating shaft. A phase fixing plate formed with a through hole for limiting retardation and a phase adjusting plate as the phase adjusting member, respectively, and the phase fixing plate and the phase adjusting plate are side surfaces of the main body of the second rotating body. The advance angle limiting recesses that engage the advance angle limiting member are defined by the inner peripheral surfaces of the respective advance angle limiting through holes and the side surface of the main body of the second rotating body. On the other hand, a retard angle limiting recess for engaging the retard angle limiting member is defined by each inner peripheral surface of each of the through holes for limiting the retard angle and a side surface of the main body of the second rotating body. The phase fixing plate is fixed to the main body of the second rotating body so as not to be relatively rotatable. While restricting relative rotation of the two rotating bodies by engaging only one of the restricting members with the inner peripheral surface of the through hole of the phase fixing plate at the circumferential end of the restricting recess corresponding thereto, The phase adjusting plate is rotated around the rotation shaft, and the other of the restricting members is engaged with only the inner peripheral surface of the through hole of the phase adjusting plate at the circumferential end of the corresponding restricting recess. The gist is to hold the valve timing at the specific time by regulating the relative rotation of the rotating body in the reverse direction.

  According to the same configuration, the phase fixing plate is fixed to the main body of the second rotating body so as not to be relatively rotatable, and the phase adjusting plate is rotated to thereby provide a restriction member provided on each of the first rotating body. Is substantially equal to the distance L1 in the circumferential direction between the portions engaging with the limiting recess and the distance L2 in the circumferential direction between the portions engaging with the limiting member in the limiting recess of the second rotating body. Thus, the same distance L2 can be adjusted. Further, both the advance angle restricting recess that engages with the advance angle restricting member and the retard angle restricting recess that engages with the retard angle restricting member include the phase fixing plate and the phase adjustment plate each having a pair of through holes formed therein. Are formed by superimposing them on the side surfaces of the main body of the rotating body. For this reason, it becomes possible to easily form them as compared with the case where additional processing is performed on the main body of the second rotating body to form each limiting recess.

  (4) The invention according to claim 4 is the variable valve operating apparatus for an internal combustion engine according to claim 2 or 3, wherein the phase adjusting member is rotated around the rotation axis by a jig. The adjustment part is provided on the outer peripheral side with respect to each of the limiting members.

  According to the same configuration, when the adjustment unit is moved, that is, when the phase adjustment member is rotated, compared with the configuration in which the adjustment unit is provided on the inner peripheral side with respect to each limitation member, The amount of change in each engagement position with the second rotating body is reduced. Therefore, the fine adjustment of these engagement positions can be easily performed, and the amount of relative rotation generated between the two rotating bodies when the valve timing is held at a specific time is reduced to a level that can be ignored. So that this can be adjusted properly.

  (5) The invention according to claim 5 is the variable valve operating apparatus for an internal combustion engine according to any one of claims 2 to 4, wherein the phase adjusting member is rotated around the rotation shaft to move both the shafts. The gist is to regulate the advancement of the valve timing from the specific time by regulating the relative rotational phase of the rotating body.

  In the situation where the valve timing is held at a specific time by the holding mechanism, the torque acting on both rotating bodies changes each time due to the reaction force of the valve springs, but on average, the valve timing is retarded The torque to be changed to is larger than the torque to be changed to the advance side.

  For this reason, after adjusting the engagement state of each limiting member and the second rotating body so that the valve timing is held at a specific time by rotating the phase adjusting member, the valve timing as described above is delayed. When torque that is to be changed to the corner side acts on the phase adjusting member, there is a concern that the adjusted engagement state changes.

  In this regard, according to the above configuration, although the torque for changing the valve timing to the advance side acts on the phase adjusting member, this is smaller than the torque for changing the valve timing to the retard side. Therefore, after adjusting the engagement state between each limiting member and the second rotating body, it can be avoided that the engagement state adjusted by such torque changes.

  (6) The invention according to claim 6 is the variable valve operating apparatus for an internal combustion engine according to any one of claims 1 to 5, wherein at least one of the rotating bodies is centered on the rotating shaft. A circular recess is provided, and the phase adjusting member is a disc fitted so as to be rotatable relative to the recess, and is rotated by being guided by a side surface of the recess in the radial direction of the rotating shaft. And

According to this configuration, the phase adjustment member rotates around the rotation axis while being guided by the side surface of the recess, and thus can be smoothly rotated.
(7) The invention according to claim 7 is an adjusting method for adjusting the holding state of the valve timing by the holding mechanism in the variable valve operating apparatus for the internal combustion engine according to claim 1, wherein the phase adjusting member is A state in which relative rotation is possible with respect to both rotating bodies, and the relative rotation of both rotating bodies is restricted by any one of the both limiting mechanisms, and the phase adjusting member is After rotating around the rotation axis and restricting relative rotation in the opposite direction to the relative rotation of both of the regulated rotating bodies, the phase adjusting member is relative to the second rotating body. The gist is to fix it so that it cannot rotate.

  According to this configuration, by restricting the relative rotation of both rotating bodies by either one of the both limiting mechanisms and by restricting the relative rotation in the opposite direction to the relative rotation by the phase adjusting member, the advance angle limiting mechanism or the delaying mechanism is controlled. This can be adjusted so that the relative rotation phase of both rotating bodies becomes small when the relative rotation is restricted by the angle limiting mechanism. Therefore, even when the valve timing is held at a specific time, even if an alternating torque acts on both rotating bodies due to the reaction force of the valve springs, the relative rotation of both rotating bodies can be suppressed. The occurrence of the hitting sound can be suppressed.

  (8) The invention according to claim 8 is an adjusting method for adjusting the holding state of the valve timing by the holding mechanism in the variable valve operating apparatus for the internal combustion engine according to claim 2, wherein the phase adjusting member is While being able to rotate relative to the second rotating body, one of the limiting members is engaged with the second rotating body to restrict the relative rotation of the rotating bodies. In this state, the phase adjustment member is rotated around the rotation axis, and one restriction member of both the restriction mechanisms is engaged with the second rotating body. The gist of the invention is that after the relative rotation in the opposite direction to the relative rotation of both rotating bodies is restricted by the same phase adjusting member, the phase adjusting member is fixed to the second rotating body so as not to be relatively rotatable.

  According to this configuration, for example, the retardation adjusting member of the retardation limiting mechanism is engaged with the second rotating body to restrict the relative rotation on the retarding side of both rotating bodies, and the phase adjustment member is rotated around the rotation axis. By rotating and engaging this with the advance limit member of the advance side limit mechanism and restricting the relative rotation in the opposite direction of both rotating bodies, the relative rotation is restricted by the advance angle limit mechanism or the retard angle limit mechanism. This can be adjusted so that the relative rotational phase of both rotating bodies becomes smaller. Similarly, the advance angle restricting member of the advance angle restricting mechanism is engaged with the second rotating body and the relative rotation of both rotating bodies is restricted, and the phase adjusting member is rotated around the rotation axis to retard it. By engaging the retard angle limiting member of the limit mechanism and restricting the relative rotation of both rotating bodies in the opposite direction, the relative rotation of both rotating bodies when the relative rotation is regulated by the advance angle limiting mechanism or the retard angle limiting mechanism This can be adjusted to reduce the rotational phase. That is, the rotational phase when regulating the relative rotation of the two rotating bodies is set so that an excessive difference does not occur between the advance angle limit time by the advance angle limit mechanism and the retard angle limit time by the delay angle limit mechanism. The valve timing can be held at a specific time while adjusting.

  (9) The invention according to claim 9 is an adjusting method for adjusting the holding state of the valve timing by the holding mechanism in the variable valve operating apparatus for the internal combustion engine according to claim 3, wherein the phase fixing plate is The second rotating body is fixed to the main body of the second rotating body so as not to be relatively rotatable, and one of the two restricting members is engaged with only the inner peripheral surface of the through hole of the same phase fixing plate at the circumferential end of the corresponding restricting recess. The relative rotation of the two rotating bodies is restricted, and in this state, the phase adjusting plate is rotated around the rotation axis, and the other end of the restricting members is connected to the circumferential end of the corresponding restricting recess. After engaging the inner peripheral surface of the through hole of the phase adjusting plate only at the portion to restrict the relative rotation of the rotating members in the opposite direction, the phase adjusting plate is moved together with the phase fixing plate to the second rotating member. The main point is to fix to the main body.

  (10) The invention according to claim 10 is an adjusting method for adjusting the holding state of the valve timing by the holding mechanism in the variable valve operating apparatus for the internal combustion engine according to claim 4, wherein the phase adjusting member is While being able to rotate relative to the second rotating body, one of the limiting members is engaged with the second rotating body to restrict the relative rotation of the rotating bodies. In this state, the phase adjusting member is rotated relative to the second rotating body by rotating the phase adjusting member around the rotation axis with a jig. The gist is to fix the phase adjusting member to the second rotating body so as not to rotate relative to the second rotating body after restricting relative rotation opposite to the relative rotation of the rotating bodies.

  According to the same configuration, when the adjustment unit is moved, that is, when the phase adjustment member is rotated, the adjustment unit is compared with the configuration in which the adjustment unit is provided on the inner peripheral side of each restriction member. A change amount of each engagement position with the second rotating body is reduced. Accordingly, the fine adjustment of the engagement positions can be easily performed, and the amount of relative rotation generated between the two rotating bodies when the valve timing is held at a specific time is reduced to a level that can be ignored. You will be able to adjust this appropriately.

1 is a schematic diagram schematically showing the structure of a variable valve operating apparatus according to an embodiment of the present invention and an internal combustion engine having the same. (A) is a top view which shows the planar structure of the variable valve mechanism which removed the cover from the variable valve mechanism, (b) is sectional drawing which shows the cross-section along a DC-DC line of (a). Sectional drawing which shows the cross-sectional structure which follows the DB-DB line | wire of Fig.2 (a). The perspective view which shows the disassembled perspective structure of a variable valve mechanism. Sectional drawing of an advance angle limiting mechanism and a retard angle limiting mechanism. Process drawing which shows the process 1 of the assembly method of a variable valve mechanism. Process drawing which shows the process 3 of the assembly method of a variable valve mechanism. FIG. 6A is a process diagram showing a holding mechanism state A after step 3 of the variable valve mechanism assembling method, and FIG. 5B is a process diagram showing a holding mechanism state B after step 3; Process drawing which shows the state which attaches a jig | tool to the mechanism in the process 4 of the assembly method of a variable valve mechanism. Process drawing which shows the state which relatively rotates a phase adjustment board to the retard side in the process 4 of the assembly method of a variable valve mechanism. Process drawing which shows the process 5 of the assembly method of a variable valve mechanism. Process drawing which shows the process 6 of the assembly method of a variable valve mechanism. (A) is sectional drawing which shows the cross-section of a holding mechanism about other embodiment of this invention, (b) is sectional drawing which shows the cross-section of the holding mechanism in the state which rotated the phase fixing plate relatively. Sectional drawing which shows the cross-section of the holding mechanism of the state which rotated the phase fixing plate relatively from the state of FIG.13 (b) about other embodiment of this invention. Sectional drawing which shows the cross-section of a variable valve mechanism about other embodiment of this invention. The perspective view which shows the perspective structure of a variable valve mechanism about other embodiment of this invention. The top view which shows the planar structure of the conventional variable valve mechanism. Sectional drawing which shows the cross-sectional structure which follows the DR-DR line | wire of FIG. 17 about the conventional variable valve mechanism.

  With reference to FIGS. 1 to 12, a variable valve operating apparatus for an internal combustion engine according to the present invention will be described as an embodiment in which the valve timing of an intake valve is changed. In the following description, the term “valve timing” simply means the valve timing of the intake valve unless otherwise specified.

  As shown in FIG. 1, an oil pan 111 for storing hydraulic oil for driving various hydraulically driven auxiliary machines is attached to the lower part of the internal combustion engine 10. On the other hand, a camshaft 13 for opening and closing an intake valve (not shown) is provided at the upper part of the internal combustion engine 10. The camshaft 13 is provided with a variable valve mechanism 20 for changing the valve timing. The rotational force of the crankshaft 11 is transmitted to the camshaft 13 from the chain 12 via the variable valve mechanism 20. As the cam shaft 13 is rotated by the rotational force of the crankshaft 11 in this way, the intake valve is driven to open and close by a cam (not shown) formed on the camshaft 13. The hydraulic oil stored in the oil pan 111 has a function as a lubricating oil for lubricating each part of the internal combustion engine 10 in addition to a function of generating a hydraulic pressure for driving the variable valve mechanism 20. ing.

  The variable valve operating apparatus includes a holding mechanism 40 for fixing the valve timing to a specific time, a hydraulic oil supply mechanism 110 that supplies hydraulic oil to the variable valve mechanism 20 and the holding mechanism 40, and the hydraulic oil supply mechanism. 110, a control device 130 for controlling the driving state of the variable valve mechanism 20, that is, the valve timing.

  The hydraulic oil supply mechanism 110 pumps up the hydraulic oil in the hydraulic pan 111 and the hydraulic oil circuit 120 including a plurality of oil passages that supply and discharge hydraulic oil between the oil pan 111 and the variable valve mechanism 20 and the holding mechanism 40. And an engine-driven oil pump 112 that supplies the hydraulic oil circuit 120. In the middle of the hydraulic oil circuit 120, a flow rate control valve 113 for controlling the supply and discharge state of the hydraulic oil with respect to the variable valve mechanism 20 and the holding mechanism 40 is provided.

  The hydraulic oil circuit 120 includes a supply oil passage 121, a discharge oil passage 122, an advance oil passage 123, a retard oil passage 124, and a release oil passage 125. The supply oil passage 121 supplies the hydraulic oil discharged from the oil pump 112 to the flow control valve 113. On the other hand, the exhaust oil passage 122 returns the hydraulic oil discharged from the variable valve mechanism 20 to the flow control valve 113 to the oil pan 111.

  Further, the advance oil passage 123 and the retard oil passage 124 allow the working oil to flow between the flow control valve 113 and each advance chamber 34 and each retard chamber 35 (both see FIG. 2). The release oil passage 125 circulates hydraulic oil between the flow control valve 113 and the restriction chamber 57 and the restriction chamber 77. The advance oil passage 123 and the retard oil passage 124 are independently connected to each advance chamber 34 and each retard chamber 35. The release oil passage 125 is connected to the restriction chamber 57 and the restriction chamber 77 in common.

  Further, the control device 130 takes in detection signals of various sensors including the crank angle sensor 131 and the cam angle sensor 132, and sets a target timing for the valve timing suitable for the engine operating state based on the detection signals. The variable valve mechanism 20 is controlled so that the target timing matches the actual valve timing.

  Next, the configuration of the variable valve mechanism 20 will be described with reference to FIGS. 1 and 2 together. FIG. 1 shows a cross-sectional structure of the variable valve mechanism 20 along the DC-DA line in FIG. FIG. 2 shows a planar structure of the variable valve mechanism 20 with the cover 23 (see FIG. 1) removed. Note that the camshaft 13 and the sprocket 21 are rotated in the rotation direction RA shown in FIG. Hereinafter, the side on which the cover 23 of the variable valve mechanism 20 is arranged in the direction of the rotation axis J of the camshaft 13 is referred to as “front end side”, and the opposite side is referred to as “base end side”. In the circumferential direction of the mechanism 20, the rotation direction RA side is defined as “advance angle side”, and the opposite side is defined as “retard angle side”.

  The variable valve mechanism 20 includes, as main components, a first rotating body that rotates in synchronization with the camshaft 13 and a second rotating body that rotates in synchronization with the crankshaft 11 in order to change the valve timing. The valve timing is changed by relatively rotating these two rotating bodies around the rotation axis J of the camshaft 13. Specifically, the variable valve mechanism 20 provided on the distal end side of the cam shaft 13 is fitted into the housing 22 as a first rotating body, and a center bolt 27 and a press fit are inserted into the distal end side of the cam shaft 13. A vane rotor 24 fixed to the camshaft 13 so as to rotate together with a pin (not shown) is provided. The vane rotor 24 is provided with a boss 24A located at the center thereof and three vanes 24B extending from the boss 24A toward the radially outer side of the rotation axis J of the camshaft 13.

  The variable valve mechanism 20 includes a sprocket 21, a housing 22, a cover 23, a phase adjusting plate 25, and a phase fixing plate 26 as a second rotating body. The sprocket 21 constitutes the main body of the second rotating body, and is drivingly connected via the crankshaft 11 and the chain 12. The housing 22 and the cover 23 are fastened together with the sprocket 21 by three bolts 28 so as to be integrally rotatable. The phase adjusting plate 25 and the phase fixing plate 26 are assembled on the tip end side of the sprocket 21 and sandwiched between the sprocket 21 and the housing 22 in the axial direction. The phase adjusting plate 25 functions as a phase adjusting member having a function of adjusting the holding phase when holding the relative rotation of the first and second rotating bodies through the holding mechanism 40 described above.

  The housing 22 is provided with three partition portions 31 that extend inward in the radial direction of the rotating shaft J and that contact the outer peripheral surface of the boss 24A via a sliding member (not shown). In the housing 22, three storage chambers 32 for storing the vanes 24 </ b> B are partitioned by the partition portion 31.

  Each partition 31 is provided with a through-hole 33 that penetrates along the axial direction of the rotation axis J. Bolts 28 are inserted into the respective through holes 33. Each bolt 28 is screwed into the sprocket 21, whereby the sprocket 21, the housing 22 and the cover 23 are integrally fastened.

  Each storage chamber 32 is sealed by the cover 23, the sprocket 21, and the boss 24A, and is divided into an advance chamber 34 and a retard chamber 35 by a vane 24B. By controlling the supply and discharge state of the hydraulic oil to and from the advance chamber 34 and the retard chamber 35 through the flow control valve 113, the relative rotation phase of the vane rotor 24 with respect to the housing 22, that is, the relative rotation of the cam shaft 13 with respect to the crankshaft 11. The phase is changed. Thereby, the valve timing opened and closed by the camshaft 13 is changed. Hereinafter, the relative rotational phase between the rotational phase PH of the housing 22 and the rotational phase PR of the vane rotor 24 is referred to as “relative rotational phase PS”.

Next, a method for changing the valve timing by the variable valve mechanism 20 will be described.
When the operating oil is supplied to the advance chamber 34 and the operating oil in the retard chamber 35 is discharged, the valve timing is advanced when the vane rotor 24 rotates toward the advance side with respect to the housing 22. Horned. When the side surface on the advance side of the vane 24B comes into contact with the side surface on the retard side of the partition portion 31 and the vane rotor 24 cannot rotate further toward the advance side with respect to the housing 22, the valve timing is It is the most advanced time in the variable region.

  On the other hand, when the operating oil is supplied to the retard chamber 35 and the hydraulic oil in the advance chamber 34 is discharged, the vane rotor 24 rotates toward the retard side with respect to the housing 22, and the valve timing is reached. Is retarded. When the side surface on the advance side of the vane 24B comes into contact with the side surface on the retard side of the partition portion 31 and the vane rotor 24 cannot rotate further toward the retard side with respect to the housing 22, the valve timing becomes It is the most retarded timing in the variable region.

  In addition, the variable valve mechanism 20 is provided with a holding mechanism 40 that holds the valve timing at an intermediate angular timing that is a specific timing between the most retarded timing and the most advanced timing. Here, the intermediate angle timing is a valve timing suitable for starting the engine. Hereinafter, a detailed configuration of the holding mechanism 40 will be described with reference to FIG.

  As shown in FIG. 3, the holding mechanism 40 includes an advance angle limiting mechanism 50 and a retard angle limiting mechanism 70. The advance angle limiting mechanism 50 regulates the relative rotation of the vane rotor 24 and the housing 22 so that the relative rotation phase PS is more advanced than the rotation phase corresponding to the valve timing of the intermediate angle timing (hereinafter referred to as “intermediate phase PM”). The rotation phase is limited. The retard restriction mechanism 70 restricts relative rotation of the vane rotor 24 and the housing 22 so as to restrict the relative rotation phase PS to a rotation phase on the retard side with respect to the intermediate phase PM. The holding mechanism 40 uses the advance angle limiting mechanism 50 and the retard angle limiting mechanism 70 to hold the valve timing at the intermediate angle timing.

  The advance angle limiting mechanism 50 is provided on the vane 24B and has a pin-shaped advance angle limiting member 51 that can reciprocate in the axial direction, an advance angle limiting operation unit 52 that reciprocates the pin advance angle limiting member 51, the sprocket 21, and the phase adjustment plate 25. And an advance angle limiting recess 53 which is provided on each of the phase fixing plates 26 and contacts an end portion on the proximal end side in the axial direction of the advance angle limiting member 51 (hereinafter referred to as “front end portion 51A”). The advance angle limiting operation portion 52 is housed in a space 54 formed in the vane 24B, and is configured by a spring 55 that urges the advance angle limiting member 51 toward the base end side. In this space 54, a spring chamber 56 in which the spring 55 is accommodated, and a restriction chamber 57 that pushes the advance angle limiting member 51 to the distal end side when hydraulic oil is supplied from the hydraulic oil supply mechanism 110 (see FIG. 1). It is divided into. The advance angle limiting recess 53 is formed by the side surface 21F on the tip side of the sprocket 21 and the inner peripheral surface of the first advance through hole 91 of the phase adjusting plate 25 and the inner peripheral surface of the second advance through hole 101 of the phase fixing plate 26. It is configured.

  When the hydraulic pressure in the limiting chamber 57 is smaller than the force of the spring 55, the advance angle limiting member 51 operates toward the base end side. On the other hand, when the hydraulic pressure in the limiting chamber 57 is greater than the force of the spring 55, the advance angle limiting member 51 operates toward the tip side.

  The advance angle limiting recess 53 is provided with two grooves having different depths, that is, an advance angle upper step groove 61 having a small depth and an advance angle lower step groove 62 having a large depth. Between the advance angle upper step groove 61 and the advance angle lower step groove 62, an advance angle step portion 63 serving as a boundary between these grooves is provided.

  The advance angle side end of the advance angle limiting recess 53, that is, the advance angle side end of the advance angle upper step groove 61 (hereinafter referred to as “first advance angle end portion 53 </ b> A”) is the tip of the advance angle limiting member 51. The position is set so that the valve timing becomes the intermediate angular timing when the part 51A comes into contact. An end portion on the retard side of the advance angle limiting recess 53, that is, an end portion on the retard side of the advance angle upper groove 61 (hereinafter referred to as “first retard end portion 53B”) is the tip of the advance angle limiting member 51. The position is set so that the valve timing is the first retard timing that is retarded from the intermediate angle when the part 51A comes into contact. Further, the end of the advanced angle lower step groove 62 on the retarded side (hereinafter referred to as “first retarded end 53C”) has a valve timing higher than the intermediate angle when the tip 51A of the advance limiting member 51 comes into contact. The position is set so as to be the second retard timing that is retarded and advanced from the first retard timing. In the following description, the relative rotational phase PS corresponding to the first retarded timing is referred to as “first retarded phase PX1”, and the relative rotational phase PS corresponding to the second retarded timing is referred to as “second retarded phase”. The retardation phase PX2 ”.

  The retard angle limiting mechanism 70 is provided on the vane 24B, and includes a pin-shaped retard angle limiting member 71 that can reciprocate in the axial direction, a retard angle limiting operation unit 72 that reciprocates the pin, and the sprocket 21 and the phase adjusting plate 25. And a retardation retarding recess 73 provided on the phase fixing plate 26 and in contact with the axially proximal end of the retardation limiting member 71 (hereinafter referred to as “distal end 71A”). The retard limit operation unit 72 is housed in a space 74 formed in the vane 24B and is configured by a spring 75 that biases the retard limit member 71 toward the base end side. The space 74 is partitioned into a spring chamber 76 in which the spring 75 is accommodated, and a limiting chamber 77 that pushes the retardation limiting member 71 to the distal end side when hydraulic oil is supplied from the hydraulic oil supply mechanism 110. . The retardation limiting recess 73 is formed by the side surface 21F on the tip side of the sprocket 21 and the inner peripheral surface of the first retardation through hole 92 of the phase adjusting plate 25 and the inner peripheral surface of the second retardation through hole 102 of the phase fixing plate 26. It is configured.

  When the hydraulic pressure in the restriction chamber 77 is smaller than the force of the spring 75, the retard restriction member 71 operates toward the base end side. On the other hand, when the hydraulic pressure in the restriction chamber 77 is larger than the force of the spring 75, the retard restriction member 71 operates toward the distal end side.

  The retardation limiting recess 73 is provided with two grooves having different depths, that is, a retardation upper step groove 81 having a relatively small depth and a retardation lower step groove 82 having a relatively large depth. Between the retard upper step groove 81 and the retard lower step groove 82, a retard step portion 83 serving as a boundary between these grooves is provided.

  An advance side end of the retard restriction recess 73, that is, an advance side end of the retard upper step groove 81 or an advance side end portion of the retard lower step groove 82 (hereinafter referred to as “second advance end portion 73A”). )) Is set so that the valve timing becomes an advance timing that is on the more advanced side than the intermediate angle timing when the tip end portion 71A of the retard limit member 71 comes into contact therewith. An end on the retard side of the retard restriction recess 73, that is, an end on the retard side of the retard upper groove 81 (hereinafter referred to as “second retard end 73B”) is the tip of the retard restriction member 71. The position is set so that the valve timing becomes the third retard timing that is retarded from the first retard timing when the portion 71A comes into contact. The end of the retarding lower step groove 82 (hereinafter referred to as “third retarding end 73C”) is set to the intermediate timing when the tip 71A of the retard limiting member 71 comes into contact therewith. The position is set so that In the following description, the relative rotational phase PS corresponding to the valve timing corresponding to the third retard timing is referred to as “third retard phase PX3”.

The details of the structure of the sprocket 21, the phase adjusting plate 25, and the phase fixing plate 26 will be described with reference to FIG.
The sprocket 21 has three fastening holes 21 </ b> D to which the respective bolts 28 (see FIG. 2B) are fastened, a positioning hole 21 </ b> B for positioning at the time of manufacturing the variable valve mechanism 20, and the variable valve mechanism 20. A work hole 21 </ b> C for inserting the jig 150 (see FIG. 9) at the time of manufacture is provided. The work hole 21C is formed in a long hole shape having a longitudinal circumferential direction. Further, a concave portion 21A (see FIG. 2B) formed in an annular shape in a plan view in the axial direction is provided on the tip side of the sprocket 21.

  The phase adjusting plate 25 and the phase fixing plate 26 are respectively accommodated in the recess 21A. Specifically, the phase adjustment plate 25 is fitted in the recess 21A in a state where it is in contact with the side surface 21F that is the bottom surface of the recess 21A. The phase fixing plate 26 is fitted in the concave portion 21 </ b> A in a state in which the phase fixing plate 26 is in contact with the front surface of the phase adjusting plate 25. As a result, the phase adjusting plate 25 and the phase fixing plate 26 are assembled so as to overlap the side surface 21F of the sprocket 21.

  The phase adjusting plate 25 and the phase fixing plate 26 are circular plates that have an annular shape in plan view in the axial direction. The outer diameters of the phase adjusting plate 25 and the phase fixing plate 26 are substantially equal to the inner diameter of the recess 21A. Specifically, the outer diameters of the phase adjusting plate 25 and the phase fixing plate 26 are in a relationship of the clearance fit with the inner diameter of the recess 21A.

  The phase adjusting plate 25 includes a first advance through hole 91 that constitutes an advance lower step groove 62 (see FIG. 3) of the advance limit restricting recess 53 and a retard lower step groove 82 (see FIG. 3) of the retard restricting recess 73. ) Constituting the first retarded angle through-hole 92. The phase adjusting plate 25 has a central through hole 93 for inserting the camshaft 13 and the center bolt 27 (see FIG. 1), a bolt through hole 94 for inserting each bolt 28 (see FIG. 2), A pin through-hole 95 for inserting the press-fit pin 29 is provided. In addition, the phase adjustment plate 25 has an adjustment hole 96 for moving the phase adjustment plate 25 in the circumferential direction around the rotation axis J, and the position of the phase adjustment plate 25 with respect to the sprocket 21 when the variable valve mechanism 20 is manufactured. A notch 97 is provided for determining and allowing movement of the phase adjusting plate 25 in the circumferential direction.

  The bolt through-hole 94 and the pin through-hole 95 are formed in a long hole shape whose longitudinal direction is the longitudinal direction. In other words, a gap is formed between the respective inner circumferential surfaces constituting the bolt through hole 94 and the pin through hole 95 and the circumferential direction of the outer diameter of the bolt 28 and the outer diameter of the press-fit pin 29. Further, the inner diameter of the inner peripheral surface constituting the central through hole 93 is larger than the outer diameter of the shaft portion of the center bolt 27.

  The adjustment hole 96 is provided at a position corresponding to the first advance angle through hole 91 in the circumferential direction, and is provided on the outer peripheral side of the first advance angle through hole 91. That is, the adjustment hole 96 is provided on the outer peripheral side of the advance angle limiting member 51 and the retard angle limiting member 71 (see FIG. 3). The adjustment holes 96 are provided at positions corresponding to the working holes 21C of the sprocket 21 in the circumferential direction and the rotational radial direction, respectively.

  In the phase fixing plate 26, the second advance through-hole 101 constituting the advance angle upper step groove 61 (see FIG. 3) of the advance angle limiting recess 53 and the retard upper step groove 81 (see FIG. 3) of the retard angle limiting recess 73 are formed. ) Constituting the second retarded angle through hole 102. Further, the phase fixing plate 26 has a central through hole 103 through which the cam shaft 13 and the center bolt 27 are inserted, a bolt through hole 104 through which each bolt 28 is inserted, and a pin through hole through which the press-fit pin 29 is inserted. A hole 105 and a notch 106 for determining the position of the phase locking plate 26 relative to the sprocket 21 at the time of manufacturing the variable valve mechanism 20 are provided.

  The first advance through-hole 91 and the second advance through-hole 101 are provided at the same position in the radial direction of the rotation axis J and have a portion overlapping in the axial direction. The advance step part 63 (see FIG. 3) of the advance restriction recess 53 is configured by the retarded end of the second advance through-hole 101.

  The first retarded through hole 92 and the second retarded through hole 102 are provided at the same position in the radial direction of the rotation axis J and have a portion overlapping in the axial direction. The retardation step portion 83 (see FIG. 3) of the retardation restriction recess 73 is configured by the retardation-side end portion of the second retardation through hole 102.

  With reference to FIG. 5, the operation of the holding mechanism 40 when the housing 22 and the vane rotor 24 (see FIG. 3) are held together will be described. FIG. 5 shows the positions of the advance angle limiting member 51 and the retard angle limiting member 71 when the relative rotational phase PS is at a predetermined rotational phase. Hereinafter, the operation in which the relative rotational phase PS is changed toward the intermediate phase PM is referred to as “intermediate angle holding operation”.

The following (situation A) and (situation B) can be considered for the intermediate angle holding operation depending on the relationship between the relative rotational phase PS and the intermediate phase PM.
(Situation A) When the relative rotational phase PS is on the more retarded side than the intermediate phase PM (Situation B) When the relative rotational phase PS is on the more advanced side than the intermediate phase PM (Situation A) Occurs during idle operation. (Situation B) occurs, for example, when the internal combustion engine 10 (see FIG. 1) is stopped by operating the ignition switch after setting the engine speed to a high speed state by an accelerator operation while the vehicle is stopped.

The intermediate angle holding operation in (Situation A) will be described. In FIG. 5, the advance angle limiting member 51 and the retard angle limiting member 71 in the first to fifth rows in order from the left in the figure correspond to this operation.
In (Situation A), the vane rotor 24 (see FIG. 2) advances toward the intermediate phase PM with respect to the housing 22 (see FIG. 2). That is, the vane rotor 24 with respect to the housing 22 has a relative rotational phase PS that is retarded from the third retarded phase PX3 (first row) → third retarded phase PX3 (second row) → first retarded phase. The angle is advanced in order so that PX1 (third row) → second retardation phase PX2 (fourth row) → intermediate phase PM (fifth row). Hereinafter, the operation of the holding mechanism 40 in each row will be described.

  When the relative rotational phase PS is on the retard side with respect to the third retard phase PX3, the advance limit member 51 and the retard limit member 71 are on the retard side with respect to the advance limit recess 53 and the retard limit recess 73, respectively. positioned.

  When the relative rotational phase PS is in the third retardation phase PX3, the retardation limiting member 71 moves to the proximal end side, and the distal end portion 71A is positioned in the retardation upper stage groove 81. At this time, the advance angle limiting member 51 is positioned on the retard side with respect to the advance angle limiting recess 53. When the holding mechanism 40 is in such a state, the retardation limiting member 71 contacts the second retardation end portion 73B, so that the vane rotor 24 moves toward the retardation side with respect to the housing 22 from the third retardation phase PX3. Rotation is restricted.

  When the relative rotational phase PS is in the first retardation phase PX1, the advance angle limiting member 51 moves to the proximal end side, and the distal end portion 51A is positioned in the advance angle upper stage groove 61. At this time, the retard restriction member 71 is located in the retard upper stage groove 81. When the holding mechanism 40 is in such a state, the advance angle limiting member 51 comes into contact with the first retarded end portion 53B, so that the vane rotor 24 is retarded from the second retarded phase PX2 with respect to the housing 22. The rotation is limited.

  When the relative rotational phase PS is in the second retardation phase PX2, the advance angle limiting member 51 is further moved to the proximal end side, and the distal end portion 51A is located in the advance lower step groove 62. At this time, the retard restriction member 71 is located in the retard upper stage groove 81. When the holding mechanism 40 is in such a state, the advance angle limiting member 51 comes into contact with the second retard angle end portion 53C, so that the vane rotor 24 is retarded relative to the housing 22 from the first retard angle phase PX1. Rotation is limited.

  When the relative rotational phase PS is at the intermediate phase PM, the retardation limiting member 71 further moves to the proximal end side, and the distal end portion 71A is positioned in the retardation lower step groove 82. At this time, the contact between the advance angle restricting member 51 and the first advance angle end portion 53A restricts the rotation of the intermediate phase PM to the advance angle side, and the retard angle restricting member 71 and the third retard angle end portion 73C. The rotation of the intermediate phase PM toward the retarded angle side is restricted by the contact with. Thereby, since the vane rotor 24 is restricted from rotating relative to the housing 22, the valve timing is maintained at the intermediate angular timing. A slight gap may be formed between the advance angle limiting member 51 and the first advance angle end portion 53A. Further, a slight gap may be formed between the retardation limiting member 71 and the third retardation end portion 73C. In short, it is sufficient that the amount of relative rotation of the vane 24B with respect to the housing 22 is within a preset setting range in a state where the relative rotational phase PS is held at the intermediate phase PM. Here, the setting range refers to the hitting sound of the advance angle limiting member 51 and the advance angle limiting recess 53 with respect to the relative rotation of the vane 24B caused by the alternating torque generated by the reaction force of the valve spring of the camshaft 13, and the like. This is a range of the relative rotation amount of the vane 24B that is suppressed to a level at which the hitting sound of the retard limit member 71 and the retard limit recess 73 can be ignored.

The intermediate angle holding operation in (Situation B) will be described. In FIG. 5, the advance angle limiting member 51 and the retard angle limiting member 71 in the first to third rows in order from the right in the drawing correspond to this operation.
In (Situation B), the vane rotor 24 is retarded relative to the housing 22 toward the intermediate phase PM. That is, the vane rotor 24 with respect to the housing 22 has a relative rotational phase PS that is more advanced than the advance phase PY (first row) → advance phase PY (second row) → intermediate phase PM (third row). Advance in order so that Hereinafter, the operation of the holding mechanism 40 in each row will be described.

  When the relative rotation phase PS is more advanced than the advance angle phase PY, the advance angle limiting member 51 and the retard angle limiting member 71 are positioned on the more advanced side than the advance angle limiting recess 53 and the retard angle limiting recess 73, respectively. ing.

  When the relative rotation phase PS is in the advance phase PY, the retard limit member 71 moves to the proximal end side, and the distal end portion 71A is positioned in the retard lower step groove 82. At this time, the advance angle limiting member 51 is located outside the retard angle limiting recess 73. When the holding mechanism 40 is in such a state, the retard angle limiting member 71 contacts the second advance angle end portion 73A, so that the vane rotor 24 rotates relative to the housing 22 toward the advance angle side with respect to the advance angle phase PY. To be restricted.

  When the relative rotational phase PS is at the intermediate phase PM, the advance angle limiting member 51 moves to the proximal end side, and the distal end portion 51A is positioned in the advance angle lower step groove 62. At this time, rotation of the retard limit member 71 and the third retard end portion 73C to the retard side with respect to the intermediate phase PM is restricted, and the advance limit member 51 and the first advance end portion 53A. , The rotation to the advance side with respect to the intermediate phase PM is limited. As a result, the vane rotor 24 is restricted from rotating relative to the housing 22, so that the valve timing is maintained at the intermediate angular timing. A slight gap may be formed between the advance angle limiting member 51 and the first advance angle end portion 53A. Further, a slight gap may be formed between the retardation limiting member 71 and the third retardation end portion 73C. In short, it is only necessary that the amount of relative rotation of the vane 24B with respect to the housing 22 is within the set range in a state where the relative rotational phase PS is held at the intermediate phase PM.

  By the way, in order to hold the vane rotor 24 and the housing 22 at the intermediate angle timing without generating excessive hitting sound, the advance angle limiting member 51 is in contact with the first advance angle end 53A and the retardation angle limiting member. 71 is maintained in contact with the third retard end 73C, or the clearance between the advance limit member 51 and the first advance end 53A, and the retard limit member 71 and the third retard end. It is necessary that the total clearance with the portion 73C is within a predetermined range. That is, as shown in FIG. 2, the distance connecting the side surface in contact with the first advance angle end portion 53A of the advance angle limiting member 51 and the side surface in contact with the third delay angle end portion 73C of the retard angle limiting member 71 in the circumferential direction. (Hereinafter, “distance between limiting pins D1”) coincides with a distance (hereinafter, “interengagement distance D2”) connecting the first advance angle end portion 53A and the third retard angle end portion 73C in the circumferential direction. Alternatively, it is necessary to have a clearance CL within a predetermined range. Here, the predetermined range of the clearance CL has the same range as the above set range.

  However, the distance D1 between the limit pins and the distance D2 between the engagements may not match due to dimensional tolerances, assembly errors, and the like of the parts constituting the variable valve mechanism 20. When the distance D1 between the restricting pins is shorter than the distance D2 between the engagements, one of the restricting members 51 and 71 does not fit into the restriction recesses 53 and 73 corresponding thereto, and therefore the distance D1 between the restricting pins is the distance D2 between the engagements. Is set to be slightly longer. In other words, it is assumed that each of the limiting members 51 and 71 can be fitted into the corresponding limiting recesses 53 and 73 with appropriate clearances. Therefore, simply assembling the variable valve mechanism 20 makes it difficult to hold the vane rotor 24 and the housing 22 at the intermediate angular timing while suppressing the hitting sound to a level that can be ignored.

  In order to solve such a problem, in the present embodiment, the phase adjusting plate 25 can be rotated relative to the vane rotor 24 and the phase fixing plate 26 within a predetermined range in the circumferential direction. In the step of assembling the variable valve mechanism 20, the clearance CL is adjusted to be within a predetermined range by rotating the phase adjusting plate 25 relative to the phase fixing plate 26 and the vane rotor 24.

Next, a method for assembling the variable valve mechanism 20 will be described with reference to FIGS. 6, 7, and 9 are shown by changing the cross-sectional structure in order to explain the process contents.
The variable valve mechanism 20 is assembled by the following steps (Step 1) to (Step 7). Of these steps, (Step 4) to (Step 6) are phase adjustment methods for the relative rotational phase PS.

(Step 1) The phase adjusting plate 25 and the phase fixing plate 26 are assembled to the sprocket 21.
Specifically, as shown in FIG. 6, the positioning hole 21 </ b> B of the sprocket 21 is inserted into the positioning pin 141 provided on the assembly table 140. In this state, the two press-fit pins 29 are press-fitted into the two pin holes 21E provided in the sprocket 21, respectively. Then, the phase adjusting plate 25 is attached to the recess 21 </ b> A of the sprocket 21. At this time, the press-fit pin 29 and the positioning pin 141 are inserted through the pin through hole 95 and the notch 97, respectively. Then, the phase fixing plate 26 is attached to the phase adjusting plate 25 (sprocket 21). At this time, the positioning pin 141 is inserted into the notch 106 and the press-fit pin 29 is press-fitted into the inner peripheral surface constituting the pin through hole 105. Thereby, the phase fixing plate 26 is accommodated in the recess 21 </ b> A and fixed to the sprocket 21 and the phase adjusting plate 25 so as not to be relatively rotatable. Thus, the sprocket assembly 20A is completed.

  Further, in (Step 1), the phase adjusting plate 25 is in a state in which it can rotate relative to the phase fixing plate 26 and the sprocket 21 in the circumferential direction around the rotation axis J. The rotatable range of the phase adjustment plate 25 is the size of the clearance in the circumferential direction between the press-fit pin 29 and the pin through hole 95 of the phase adjustment plate 25. In the following description, the rotation of the phase adjustment plate 25 around the rotation axis J with respect to other members such as the phase fixing plate 26 and the vane rotor 24 (see FIG. 2) is simply “rotation of the phase adjustment plate 25”. And

(Step 2) The vane rotor 24 and the housing 22 (both see FIG. 7) are assembled.
Specifically, the vane rotor 24 is assembled to the housing 22 in a state where the holding mechanism 40 (see FIG. 3) is assembled to the vane rotor 24. Thereby, the housing assembly 20B (see FIG. 7) is completed.

(Step 3) The sprocket assembly 20A and the housing assembly 20B are temporarily assembled.
Specifically, as shown in FIG. 7, the sprocket assembly 20 </ b> A is disposed in a state where the positioning hole 21 </ b> B of the sprocket 21 is inserted into the positioning pin 141 of the assembly table 140. The housing assembly 20B is attached to the sprocket assembly 20A in a state where the positioning portion 141A of the housing 22 and the positioning portion 23A of the cover 23 are inserted through the positioning pins 141, respectively.

  Further, in this state, the restriction chamber 57 and the restriction chamber 77 (not shown in FIG. 7) are not filled with hydraulic oil, respectively, so that the advance angle limiting member 51 and the retard angle limiting member 71 (not shown in FIG. 7). Each protrudes from the vane 24B. The distal end portion 51A of the advance angle limiting member 51 and the distal end portion 71A (not shown in FIG. 7) of the retard angle limiting member 71 are in the advance angle limiting recess 53 and the retard angle limiting recess 73 (not shown in FIG. 7). Each is located. Thereby, in the state of the above (Step 2), the relative rotational phase PS is held at the intermediate phase PM.

  In this state, the vane rotor 24 is advanced with respect to the housing 22 to engage the advance angle limiting member 51 and the sprocket 21. At this time, the advance angle limiting member 51 and the first advance angle end portion 53A come into contact with each other. Accordingly, the clearance between the advance angle limiting member 51 and the first advance angle end portion 53A becomes “0”. For this reason, the advance angle limiting member 51 is restricted from rotating relative to the advance angle side.

  Next, the sprocket assembly 20A and the housing assembly 20B are loosely fastened by the bolts 28. Even in this state, the phase adjusting plate 25 can rotate relative to the sprocket 21 and the phase fixing plate 26. Thus, the temporary assembly of the variable valve mechanism 20 is completed.

(Step 4) The phase adjusting plate 25 is rotated to the retard side.
In the variable valve mechanism 20 temporarily assembled in (Step 3), as shown in FIG. 8, the holding mechanism 40 can be in the following (State A) and (State B).

  (State A) A state in which the distance D1 between the limiting pins is larger than the distance D2 between the engagements, that is, as shown in FIG. 8A, the retardation limiting member 71 is positioned in the retardation lower step groove 82 and the third retardation A state in which the clearance CL is increased by being positioned on the more advanced side than the end 73C.

  (State B) State where the distance D1 between the limiting pins is smaller than the distance D2 between the engagements, that is, as shown in FIG. 8B, the retardation limiting member 71 is not positioned in the retardation lower step groove 82, and the phase adjusting plate 25 is in contact with the tip side surface.

  Since it is difficult for the operator to discriminate these states from the outside of the variable valve mechanism 20 (see FIG. 7), the phase adjustment plate 25 is rotated so as to be unified into the state (State A). That is, as shown in FIG. 9, in the case of (state B), the pin-shaped tip 151 provided on the jig 150 for relatively rotating the phase adjusting plate 25 is used as the work hole 21C for the sprocket 21. And is fitted into the adjustment hole 96 of the phase adjustment plate 25. At this time, the distal end portion 151 is in contact with the surface on the proximal end side of the phase fixing plate 26. Next, as shown in FIG. 10, the tip portion is reached until the tip portion 151 comes into contact with the retarded side surface of the working hole 21 </ b> C, or until the third retarded end portion 73 </ b> C comes into contact with the advance limit member 51. 151 is moved toward the retarded angle side. As a result, the phase adjusting plate 25 rotates to the retard side. At this time, the distal end portion 71 </ b> A of the retardation limiting member 71 is positioned in the retardation lower step groove 82.

  In addition, the operation of rotating the phase adjusting plate 25 to the retarded angle side is also performed in advance (state A). In this case, the clearance CL between the retard limit member 71 and the third retard end 73C is further increased.

(Step 5) The clearance CL between the retard limit member 71 and the third retard end 73C is set to “0” by rotating the phase adjustment plate 25 to the advance side.
That is, as shown in FIG. 11, the phase adjustment plate 25 is rotated to the advance side by moving the tip 151 of the jig 150 toward the advance side from the state shown in FIG. Thereby, the clearance CL is set to “0”. Specifically, the clearance CL is determined to be “0” when the third retarded end portion 73 </ b> C contacts the distal end portion 71 </ b> A of the retard limit member 71. Thereby, the relative rotation opposite to the relative rotation regulated in (Step 3) is regulated.

(Step 6) The phase adjustment plate 25 is rotated to the retard side by a predetermined amount with reference to the state where the clearance CL is “0”.
Specifically, as shown in FIG. 12, in the above (Step 5), the jig 150 is moved in the opposite direction (retarded side) from the state in which the clearance CL is set to “0” (Step 5). It is adjusted so that the clearance CL is within a predetermined range by moving it by a predetermined amount. Here, the predetermined amount is a clearance CL at which excessive hitting sound is generated due to at least one of the collision of the advance angle limiting member 51 and the advance angle limiting recess 53 and the collision of the retard angle limiting member 71 and the retard angle limiting recess 73. The value is such that each of the limiting members 51 and 71 can be smoothly removed from the respective limiting recesses 53 and 73.

(Step 7) The variable valve mechanism 20 is assembled.
Specifically, the bolt 28 is tightened (that is, fully tightened) in a state in which the clearance CL is adjusted to be within the predetermined range in the above (Step 5). Thereby, the assembly of the variable valve mechanism 20 is completed. Further, in this state, the force for sandwiching the phase adjusting plate 25 and the phase fixing plate 26 by the housing 22 and the sprocket 21 becomes strong, so that the phase adjusting plate 25 is pressed from both sides in the axial direction by the phase fixing plate 26 and the sprocket 21. Thereby, the rotation of the phase adjustment plate 25 is restricted.

As described above, according to the present embodiment, the following effects can be obtained.
(1) Even when excessive relative rotation occurs in the housing 22 and the vane rotor 24 when the valve timing is held at the intermediate angular timing by the limiting mechanisms 50 and 70, by rotating the phase adjustment plate 25, The relative rotation phase PS when the relative rotation is restricted by the advance angle limiting mechanism 50 can be adjusted so that the relative rotation amount becomes small. That is, the clearance CL can be adjusted to be within a predetermined range. In other words, the valve timing can be adjusted so that a difference larger than necessary does not occur between the advance limit time by the advance limit mechanism 50 and the retard limit time by the retard limit mechanism 70. Therefore, even when an alternating torque that causes the housing 22 and the vane rotor 24 to rotate relative to each other due to the reaction force of the valve spring when the valve timing is held at the intermediate angular timing, the sound of the hitting sound is not generated. It can be suppressed to a negligible level.

  Further, after the variable valve mechanism 20 is temporarily assembled in (Step 3), the phase adjustment plate 25 is rotated in (Step 4) to (Step 6) to adjust the clearance CL. Thus, when the relative rotational phase PS is held at the intermediate phase PM through the both limiting mechanisms 50 and 70, the clearance CL is within a predetermined range due to the existence of dimensional errors, assembly errors, and the like of the members constituting the limiting mechanisms 50 and 70. However, the clearance CL can be adjusted to be within a predetermined range through (Step 4) to (Step 6).

  (2) The advance angle limiting recess is formed by the first advance angle through hole 91 and the first retard angle through hole 92 of the phase adjusting plate 25 and the second advance angle through hole 101 and the second retard angle through hole 102 of the phase fixing plate 26. 53 and a retard restriction recess 73 are formed. Therefore, compared with the case where the grooves for forming the advance angle limiting recess 53 and the retard angle limiting recess 73 are additionally formed in the sprocket 21, these limiting recesses 53 and 73 can be easily formed.

  (3) Since the adjustment hole 96 is provided on the outer peripheral side with respect to the advance angle limiting member 51, the adjustment portion is compared with the configuration in which the adjustment hole of the phase adjustment plate 25 is provided on the inner peripheral side with respect to the advance angle limiting member 51. When moved, that is, when the phase adjusting plate 25 is rotated, the amount of change in the engagement position between each of the limiting members 51 and 71 and the first advance end 53A and the third retard end 73C becomes small. Therefore, the fine adjustment of the first advance angle end portion 53A and the third retard angle end portion 73C can be easily performed, and the relative rotation generated between the housing 22 and the vane rotor 24 when the valve timing is maintained at the intermediate angle timing. This amount can be adjusted appropriately so that the amount of is reduced to a negligible size.

  (4) When the phase adjustment plate 25 accommodated in the recess 21A of the sprocket 21 rotates, it is guided to the inner surface of the recess 21A. For this reason, when rotating the phase adjustment plate 25, it can suppress that the phase adjustment plate 25 moves to radial direction. Thereby, the phase adjustment plate 25 can be smoothly rotated.

  In addition, with such a configuration, the inner diameter of the inner peripheral surface constituting the bolt through hole 94 of the phase adjusting plate 25 and the inner diameter of the inner peripheral surface constituting the pin through hole 95 are the outer diameter of the bolt 28 and the press-fit pin 29. It can also be larger than the outer diameter over the entire circumference in the circumferential direction. Thereby, the bolt 28 and the press-fit pin 29 can be easily inserted into the phase adjusting plate 25.

  (5) When the phase adjusting plate 25 and the phase fixing plate 26 are attached to the sprocket 21, the positioning hole 141 of the sprocket 21, the notch 97 of the phase adjusting plate 25 and the notch of the phase fixing plate 26 on the positioning pin 141 of the assembly table 140. Each part 106 is inserted. For this reason, the phase adjusting plate 25 and the phase fixing plate 26 are attached to the sprocket 21 by inserting the press-fit pins 29 into the pin through holes 95 and 105 and inserting the positioning pins 141 into the notches 97 and 106, respectively. As a result, it is possible to prevent an erroneous operation of the combination of the first advance through-hole 91 and the second advance through-hole 101 and the combination of the first retard through-hole 92 and the second retard through-hole 102. can do.

  (6) When the clearance between the advance angle limiting member 51 and the first advance angle end portion 53A and the clearance between the retard angle limiting member 71 and the third retardation angle end portion 73C are both generated, the total of these clearances is within a predetermined range. When adjusting inward, it is difficult to set a reference position for measuring each clearance. Therefore, it may not be possible to determine whether the total clearance is within a predetermined range.

  In this regard, in this embodiment, after the clearance between the advance angle limiting member 51 and the first advance angle end portion 53A is set to “0” in (Step 3), in (Step 5), the retard angle limiting member 71 and The clearance CL with the third retarded end portion 73C is set to “0”. For this reason, the reference position for measuring the clearance CL can be set by setting the position where the clearance CL is “0” as the reference position. Therefore, in (Step 6), the clearance CL can be adjusted in accordance with the amount of movement of the jig 150 so that the clearance CL is within a predetermined range.

(Other embodiments)
The specific configuration of the variable valve operating apparatus for an internal combustion engine of the present invention is not limited to the contents exemplified in the above embodiment, and can be changed as follows, for example. The following modifications are not applied only to the above-described embodiment, and different modifications can be combined with each other.

  In the above embodiment, all of the first advance through holes 91 of the phase adjusting plate 25 are overlapped with the second advance through holes 101 of the phase fixing plate 26, but a part of the first advance through hole 91 is the first. Polymerization with the binary angle through-hole 101 is also possible. Further, all of the first retarded through holes 92 of the phase adjusting plate 25 overlapped with the second retarded through holes 102 of the phase fixing plate 26, but a part of the first retarded through hole 92 is the second retarded through hole. Polymerization with 102 is also possible.

  In the above embodiment, the relative rotation phase PS is held at the intermediate phase PM by rotating the phase adjustment plate 25 to bring the third retardation end portion 73C into contact with the retardation restriction member 71 of the retardation restriction mechanism 70. Although it was a structure, the structure which hold | maintains relative rotational phase PS in the intermediate | middle phase PM is not restricted to this. For example, as shown in FIGS. 13 and 14, the first advance angle end portion 53 </ b> A contacts the advance angle limiting member 51 of the advance angle limiting mechanism 50 by rotating the phase fixing plate 26 with respect to the phase adjustment plate 25. Thus, the relative rotational phase PS can be held at the intermediate phase PM. Specifically, as shown in FIG. 13B, the phase fixing plate 26 is rotated to the retard side by the jig 150 from the state shown in FIG. Accordingly, the clearance CL between the advance angle limiting member 51 and the first advance angle end portion 53A is set to “0”. Then, as shown in FIG. 14, the clearance CL is adjusted within a predetermined range by rotating the phase fixing plate 26 toward the advance side by a predetermined amount from the state of FIG. 13B.

  By the way, in general, when the relative rotational phase PS is held at the intermediate phase PM, the torque acting on each of the housing 22 and the vane rotor 24 varies depending on the reaction force of the valve spring, etc. The torque for changing the valve timing to the retard side is larger than the torque for changing the valve timing to the advance side. That is, in the above state, the torque applied to the retard limit member 71 is larger than the torque applied to the advance limit member 51. For this reason, if the torque is applied to the retardation limiting member 71 after the phase adjustment plate 25 is rotated to adjust the relative rotation phase PS, there is a concern that the engagement state adjusted by the phase adjustment plate 25 changes.

  In this respect, in the present embodiment, the phase fixing plate 26 is in a state of being rotatable relative to the sprocket 21, the phase fixing plate 26 contacts the advance side of the advance angle limiting member 51, and the phase fixing plate 26 is rotated. The relative rotational phase PS is adjusted by moving it. As a result, torque that changes the valve timing toward the advance side acts on the phase fixing plate 26, but this is relatively smaller than the torque that attempts to change the valve timing toward the retard side. After adjusting the state in which the relative rotational phase PS is held at the intermediate phase PM by the fixing plate 26, it is possible to prevent the engagement state adjusted by such torque from changing. In this case, the phase adjusting plate 25 is fixed to the sprocket 21 so as not to be relatively rotatable.

  In the above embodiment, the phase adjusting plate 25 and the phase fixing plate 26 are each formed of a single disk, but the shapes of the phase adjusting plate 25 and the phase fixing plate 26 are not limited thereto. For example, the phase adjusting plate 25 and the phase fixing plate 26 can be configured by a combination of a plurality of arc members. Specifically, the phase adjustment plate 25 can be formed as a disc by combining a first arc member having the first advance through hole 91 and a second arc member having the first retard through hole 92. The same applies to the phase fixing plate 26.

  Further, as the phase adjusting member, the phase adjusting plate 25 is a flat plate having the first advance through hole 91 or the phase adjusting plate 25 is a flat plate having the first retard through hole 92 or the first advance through hole 91 and the first retard. It can also be comprised from either of the flat plates which have both the square through-holes 92. In short, the phase adjusting member may have any shape as long as the inter-engagement distance D2 can be adjusted by relatively rotating the member.

  In the above embodiment, the advance angle limiting recess 53 and the retard angle limiting recess 73 are the first advance through hole 91 and the first retard through hole 92 of the phase adjusting plate 25 and the second advance through hole of the phase fixing plate 26. 101 and the second retarded through hole 102 are configured, but the configurations of the advance angle limiting recess 53 and the retard angle limiting recess 73 are not limited thereto. For example, the phase fixing plate 26 may be omitted. Specifically, an advance lower step groove 62 and a retard lower step groove 82 are provided on the tip side of the sprocket 21. Then, the phase adjusting plate 25 is assembled to the sprocket 21 so as to be relatively rotatable.

-In the assembly method of the variable valve mechanism 20 of the said embodiment, (process 1) and (process 2) can also be made into the reverse order.
In the above embodiment, as the structure of the holding mechanism 40, the advance angle limiting recess 53 and the retard angle limiting recess 73 are provided on the sprocket 21 side, but at least one of these limit recesses 53, 73 is provided on the cover 23 side. You can also. Specifically, for example, as shown in FIG. 15, when the retard restriction recess 73 is provided on the cover 23 side, the advance lower step groove 62 and the retard lower step are formed on the distal end side of the sprocket 21 and the proximal end side of the cover 23. Each groove 82 is provided. At this time, the first advance through-hole 91 and the first retard through-hole 92 of the phase adjusting plate 25 constitute an advance upper step groove 61 and a retard upper step groove 81, respectively. A phase fixing plate 26 is provided on the cover 23 side. At this time, the phase adjusting plate 25 is attached to the sprocket 21 so as to be relatively rotatable in the circumferential direction, and the phase fixing plate 26 is fixed to the housing 22 or the cover 23 so as not to be relatively rotatable. In this case, the housing 22 is provided with a recess corresponding to the recess 21 </ b> A of the sprocket 21. The phase fixing plate 26 is accommodated in the recess.

  Further, in the configuration of the holding mechanism 40 shown in FIG. 15, the phase adjusting plate 25 can be fixed to the sprocket 21 and the phase fixing plate 26 can be attached to the cover 23 in a relatively rotatable state.

  In this case, instead of adjusting the relative rotational phase PS by the phase adjusting plate 25, the relative rotational phase PS can be adjusted by the phase fixing plate 26. Specifically, a hole corresponding to the work hole 21C of the sprocket 21 is provided in the cover 23, and a hole corresponding to the adjustment hole 96 of the phase adjustment plate 25 is provided in the phase fixing plate 26 (Step 4) to The operation of adjusting the relative rotational phase PS in (Step 6) is performed.

  Further, in the configuration of the holding mechanism 40 shown in FIG. 15, when the work for adjusting the relative rotational phase PS is performed by the phase fixing plate 26, as shown in FIG. 16, from the side (radial direction) of the variable valve mechanism 20. The phase fixing plate 26 can also be rotated with respect to the cover 23. Specifically, the center protrusion 161 provided on the jig 160 for relatively rotating the phase fixing plate 26 is fitted into the notch 106 of the phase fixing plate 26 and the holding provided on the jig 160 is held. In a state where the protrusion 162 is fitted to the outer surface of the phase fixing plate 26, the jig 160 is moved in the circumferential direction. Thereby, the relative rotational phase PS can be adjusted. In this case, the notch 106 corresponds to the adjustment unit.

  In the above embodiment, as the structure of the holding mechanism 40, the advance angle restricting member 51 and the retard angle restricting member 71 are provided in the vane rotor 24, respectively, and the advance angle restricting recess 53 and the retard angle restricting recess 73 are provided in the sprocket 21, The configuration of the holding mechanism 40 is not limited to this. The advance angle restricting member 51 and the retard angle restricting member 71 may be provided in the sprocket 21, respectively, and the advance angle restricting recess 53 and the retard angle restricting recess 73 may be provided in the vane rotor 24. Further, one of the advance angle limiting member 51 and the retard angle limiting member 71 can be provided on the sprocket 21 and the other can be provided on the vane rotor 24. In this case, of the advance angle limiting recess 53 and the retard angle limiting recess 73, a limit recess corresponding to the limit pin provided in the sprocket 21 can be provided in the vane rotor 24 and the other limit recess can be provided in the sprocket 21.

  In the above embodiment, the vane rotor 24 is provided as the first rotating body, but the sprocket 21, the housing 22, the cover 23, the phase adjusting plate 25, and the phase fixing plate 26 may be provided as the first rotating body. . In this case, the second rotating body is the vane rotor 24.

In the above embodiment, the variable valve mechanism 20 and the holding mechanism 40 are controlled by one flow control valve 113, but both mechanisms can be controlled by individual flow control valves.
In the above embodiment, the relative rotational phase PS is held at the intermediate phase PM, but the relative rotational phase PS is held at the rotational phase at which the valve timing is the most advanced timing, and the relative rotational phase PS is at the maximum valve timing. It is also possible to maintain the rotational phase that is the retard timing.

  In the above embodiment, the variable valve mechanism 20 that changes the valve timing of the camshaft 13 of the intake valve is provided. However, instead of or in addition to this, the variable movement that changes the valve timing of the camshaft of the exhaust valve is provided. A valve mechanism 20 can also be provided.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 11 ... Crankshaft, 12 ... Chain, 13 ... Cam shaft, 20 ... Variable valve mechanism, 20A ... Sprocket assembly, 20B ... Housing assembly, 21 ... Sprocket, 21A ... Recess, 21B ... Positioning hole , 21C: working hole, 21D: fastening hole, 21E: pin hole, 21F ... side face, 22 ... housing, 22A ... positioning part, 23 ... cover, 23A ... positioning part, 24 ... vane rotor, 24A ... boss, 24B ... vane , 25 ... phase adjusting plate (phase adjusting member), 26 ... phase fixing plate, 27 ... center bolt, 28 ... bolt, 29 ... press-fit pin, 31 ... partition, 32 ... receiving chamber, 33 ... through hole, 34 ... advance Angle chamber, 35 ... retard chamber, 40 ... holding mechanism, 50 ... advance limit mechanism, 51 ... advance limit member, 51A ... tip, 52 ... advance limit operation part, 53 ... advance limit recess ( Limit recess), 53A ... first advance end, 53B ... first retard end, 53C ... second retard end, 54 ... space, 55 ... spring, 56 ... spring chamber, 57 ... restriction chamber, 61 ... Advance angle upper step groove, 62 ... Advance angle lower step groove, 63 ... Advance angle step portion, 70 ... Delay angle limit mechanism, 71 ... Delay angle limit member, 71A ... Tip end portion, 72 ... Delay angle limit operation portion, 73 ... Delay Angle limiting recess (restriction recess), 73A ... second advance end, 73B ... second retard end, 73C ... third retard end, 74 ... space, 75 ... spring, 76 ... spring chamber, 77 ... Restricted chamber, 81 ... retarded upper step groove, 82 ... retarded lower step groove, 83 ... retarded stepped portion, 91 ... first advance through hole, 92 ... first retarded through hole, 93 ... central through hole, 94 ... Bolt through-hole, 95 ... pin through-hole, 96 ... adjustment hole (adjustment part), 97 ... notch, 101 ... second advance through-hole, 102 ... second retard through-hole, 103 ... center through 104, bolt through hole, 105 ... pin through hole, 106 ... notch (adjustment part), 110 ... hydraulic oil supply mechanism, 111 ... oil pan, 112 ... oil pump, 113 ... flow control valve, 120 ... hydraulic oil Circuit 121, supply oil passage 122, discharge oil passage 123, advance oil passage 124, retard oil passage 125, release oil passage 130 control device 131 crank angle sensor 132 cam angle Sensors 140... Assembly stand 141. Positioning pin 150. Jig 151. Tip end 160. Jig 161. Central projection 162 162 Holding projection.

Claims (10)

The cam includes a first rotating body that rotates in synchronization with one of the crankshaft and the camshaft, and a second rotating body that rotates in synchronization with the other, and the two rotating bodies are relatively rotated around the same rotating shaft. A variable valve mechanism that changes the valve timing of a valve that is driven to open and close by a shaft; an advance angle limiting mechanism that limits the advance angle of the valve timing by restricting the relative rotation of the two rotary bodies; A variable valve operating apparatus for an internal combustion engine, which is provided with a delay angle limiting mechanism that limits the delay angle of the valve timing by restricting rotation, and a holding mechanism that holds the valve timing at a specific time by the cooperation of the limit mechanisms Because
The holding mechanism includes a phase adjusting member, and the phase adjusting member regulates relative rotation in one direction of the two rotating bodies when the valve timing is limited by any one of the limiting mechanisms. A variable valve operating apparatus for an internal combustion engine, wherein the relative rotational phase of the two rotating bodies at the time of regulation is adjusted by rotating around the rotating shaft. The first rotating body is provided with an advance angle restricting member and a retard angle restricting member spaced apart from each other in the circumferential direction of the rotation shaft, and the advance angle restricting mechanism moves the advance angle restricting member to the second rotation. While the valve timing advance angle is limited by being engaged with the body, the retard angle limiting mechanism is configured to limit the valve timing delay angle by engaging the delay angle limiting member with the second rotating body. The phase adjusting member is assembled to the second rotating body as a part of the second rotating body and rotates around the rotating shaft to engage with either one of the restricting members. The variable valve operating apparatus for an internal combustion engine according to claim 1, wherein relative rotation in one direction is restricted by a relative rotation phase of the two rotating bodies when the valve timing becomes the specific time. The holding mechanism includes a phase fixing plate in which an advance angle limiting through hole and a retard angle limiting through hole are formed at positions spaced apart in the circumferential direction of the rotating shaft, and a phase adjustment plate as the phase adjustment member The phase fixing plate and the phase adjusting plate are superimposed on the side surface of the main body of the second rotating body and assembled to each inner peripheral surface of each of the advance angle limiting through holes, and the second The advance angle restricting recess with which the advance angle restricting member engages is defined by the main body side surface of each of the rotating bodies, while the inner peripheral surfaces of the respective retard angle restricting through holes and the second rotation A retardation limiting recess for engaging the retardation limiting member is defined by a body side surface of the body,
In a state where the phase fixing plate is fixed to the main body of the second rotating body so as not to be relatively rotatable, one of the restricting members is inserted into the through hole of the phase fixing plate at the circumferential end of the corresponding restricting recess. Engaging only the peripheral surface to restrict the relative rotation of the two rotating bodies, while rotating the phase adjusting plate around the rotation shaft, the other end of the limiting members corresponding to the circumferential end of the limiting recess 3. The internal combustion engine according to claim 2, wherein the valve timing is maintained at the specific time by engaging only with the inner peripheral surface of the through-hole of the same phase adjusting plate in the portion and restricting the relative rotation in the opposite direction of the two rotating bodies. Variable valve gear for engine. 4. The variable valve for an internal combustion engine according to claim 2, wherein the phase adjustment member is provided with an adjustment portion for rotating the phase adjustment member around the rotation axis by a jig on the outer peripheral side of the restricting members. apparatus. 5. The phase adjustment member is configured to regulate the advancement of the valve timing from the specific time by turning around the rotation axis and regulating the relative rotation phase of the two rotary bodies. A variable valve operating apparatus for an internal combustion engine according to the item. At least one of the rotating bodies is provided with a circular recess centered on the rotating shaft,
The said phase adjustment member is a disk fitted so that relative rotation with respect to the said recessed part is carried out, and it is guided and rotated by the side surface in the radial direction of the said rotating shaft of the said recessed part. A variable valve operating apparatus for an internal combustion engine according to claim 1. An adjustment method for adjusting a holding state of valve timing by the holding mechanism in the variable valve operating apparatus for an internal combustion engine according to claim 1,
While the phase adjustment member is in a state capable of relative rotation with respect to the two rotating bodies, and the relative rotation of the both rotating bodies is restricted by either one of the two limiting mechanisms, The phase adjustment member is rotated around the rotation axis to restrict relative rotation in the opposite direction to the relative rotation of the two rotating bodies to be regulated, and then the phase adjustment member is moved to the second phase. A valve timing holding state adjusting method characterized by fixing the rotating body so as not to rotate relative to the rotating body. An adjustment method for adjusting a holding state of valve timing by the holding mechanism in the variable valve operating apparatus for an internal combustion engine according to claim 2,
The phase adjusting member is brought into a state in which the phase adjusting member can be rotated relative to the second rotating body, and one of the limiting mechanisms is engaged with the second rotating body so that the both rotating bodies are engaged. In a state in which relative rotation is restricted, and in this state, the phase adjusting member is rotated around the rotation shaft to engage one of the limiting members of the both limiting mechanisms with the second rotating body. After the relative rotation in the opposite direction to the relative rotation of the two rotating bodies regulated by the above is regulated by the same phase adjusting member, the phase adjusting member is fixed to the second rotating body so as not to be relatively rotatable. To adjust the hold timing of the valve timing. An adjustment method for adjusting a holding state of valve timing by the holding mechanism in the variable valve operating apparatus for an internal combustion engine according to claim 3,
The phase fixing plate is fixed to the main body of the second rotating body in a relatively non-rotatable manner, and one of the limiting members is fixed to the inner peripheral surface of the through hole of the phase fixing plate at the circumferential end of the limiting recess corresponding thereto. The relative rotation of both rotating bodies is restricted by engaging only with the rotation member, and in this state, the phase adjusting plate is rotated around the rotation axis, and the other of the restricting members corresponds to it. After restricting relative rotation of the rotating bodies in the opposite direction by engaging only the inner peripheral surface of the through hole of the phase adjusting plate at the circumferential end of the limiting recess, the phase adjusting plate is used together with the phase fixing plate. The valve timing holding state adjusting method, wherein the valve timing holding state is fixed to the main body of the second rotating body. An adjustment method for adjusting a holding state of valve timing by the holding mechanism in the variable valve operating apparatus for an internal combustion engine according to claim 4,
The phase adjusting member is brought into a state in which the phase adjusting member can be rotated relative to the second rotating body, and one of the limiting mechanisms is engaged with the second rotating body so that the both rotating bodies are engaged. In a state where relative rotation is restricted, and the phase adjustment member is rotated relative to the second rotating body by rotating the phase adjustment member around the rotation axis with a jig under the state. The phase adjustment member is fixed to the second rotating body so as not to be rotatable relative to the second rotating body after restricting relative rotation opposite to the relative rotation of the two rotating bodies to be controlled by rotation. Holding state adjustment method.

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