JP6003865B2 - Valve timing adjustment device - Google Patents

Description

  The present invention relates to a valve timing adjusting device that adjusts the valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine.

  2. Description of the Related Art Conventionally, a valve timing adjusting device including a housing rotor that rotates in conjunction with a crankshaft and a vane rotor that rotates in conjunction with a camshaft is known. For example, Patent Document 1 discloses that the rotation phase of the vane rotor with respect to the housing rotor is set to the advance direction or the retard direction by introducing the working fluid into the advance chamber or the retard chamber divided in the rotation direction by the vane rotor in the housing rotor. What is changed is disclosed. In the apparatus of Patent Document 1, a control valve is used that controls the entry and exit of hydraulic fluid into and from the advance chamber and the retard chamber by reciprocating in the axial direction of a spool accommodated in the sleeve.

  In the device of Patent Document 1, the spool is in accordance with the balance between the axial driving force generated by the driving source according to the command value and the axial biasing force adjusted by the biasing adjustment structure against the driving force. ,Moving. Here, as the bias adjustment structure, a structure in which a movable member and a pair of elastic members are accommodated in a sleeve is employed.

  Specifically, in the first region and the second region aligned in the axial direction as the movement region of the spool in the sleeve, the first restoring force that urges the spool in the axial direction is generated by the first elastic member, A second restoring force for urging the movable member in the axial direction is generated by the second elastic member. In such a configuration, in the first region where the spool engaged with the movable member is biased by the second restoring force, the resultant force of the second restoring force and the first restoring force is used as the biasing force against the driving force. Receive. On the other hand, in the second region where the movable member engages with the sleeve and the biasing of the spool by the second restoring force is limited, the spool receives the first restoring force as the biasing force against the driving force. Therefore, at the boundary position between the first region and the second region, the urging force is stepped by switching between the combined action of the first restoring force and the second restoring force and the single action of the first restoring force. To change. As a result, it is possible to appropriately switch the required performance in each area.

JP 2012-149597 A

  Now, in the apparatus of Patent Document 1, the cylindrical movable member is separated from the sleeve radially inward, and supported by the spool from the radially inner side. As a result, in the first region, the movable member that moves together with the engaged spool is restricted from contacting in the radial direction with respect to the sleeve, so that the movement resistance of the spool is reduced. Therefore, as shown in FIG. 15, in the first region, the spool movement position with respect to the command value to the drive source is between the movement in the forward direction Dg and the reverse direction Dr in the axial direction. Hysteresis is unlikely to occur. On the other hand, in the second region, the spool moves relative to the movable member that is stopped by the engaged sleeve while contacting in the radial direction, so the sliding resistance between the contact elements becomes the movement resistance of the spool. . At this time, the movable member is pressed against the sleeve in the axial direction by the second restoring force, thereby being restricted from being pressed against the spool in the radial direction by the side force resulting from the inclination of the second restoring force. . As a result, the sliding resistance between the movable member and the spool is reduced to some extent, but as long as the movable member is supported by the spool, there is a limit to the reduction of the sliding resistance. Therefore, as shown in FIG. 15, even in the second region with respect to the movement position of the spool with respect to the command value, there is a larger hysteresis than that in the first region between the movement in the forward direction Dg and the movement in the backward direction Dr. Arise. For this reason, there is room for improvement in suppressing variations in control valve response.

  The present invention has been made in view of the above problems, and an object thereof is to provide a valve timing adjusting device that suppresses responsiveness variation in a control valve capable of appropriately switching required performance.

  The invention disclosed in order to solve the above-described problem is a valve timing adjusting device that adjusts the valve timing of a valve that opens and closes a camshaft (2) by torque transmission from a crankshaft in an internal combustion engine. A housing rotor (11) that rotates in conjunction with the camshaft, and an advance chamber (22, 23, 24) and a retard chamber (26, 27, 28) in the housing rotor that rotate in conjunction with the camshaft, By introducing the hydraulic fluid into the advance chamber or retard chamber, the vane rotor (14) whose rotational phase with respect to the housing rotor changes in the advance direction or the retard direction, and the spool ( 70) reciprocates in the axial direction along the movable line (O), so that the control valve (60) for controlling the entry and exit of the working fluid into and from the advance chamber and the retard chamber is connected to the spool. A driving source (90) that generates a driving force for driving in the direction according to the command value, and an urging adjustment structure (94) for adjusting the urging force that urges the spool in the axial direction against the driving force, The first region (Ra) and the second region (Rl) as regions in which the spool moves within the sleeve are set side by side in the axial direction, and the bias adjustment structure includes a sleeve stopper (680) provided on the sleeve, A spool stopper (72) provided on the spool, and a first elastic member (80) that is accommodated in the sleeve and generates a first restoring force (F1) that urges the spool in the axial direction in the first region and the second region. And a second restoring force (F2) that urges the spool in the axial direction is generated in the first region that is accommodated in the sleeve and engages the spool stopper, while the second region that engages the sleeve stopper And a second elastic member (82) for limiting the biasing of the spool by the second restoring force, and the spool stopper in the first region and the second region is a sleeve in a radial direction perpendicular to the movable line. And a portion (U, L) that is separated from the sleeve stopper in the circumferential direction around the movable line is moved.

  According to this invention, in the first region where the second elastic member engages with the spool stopper provided on the spool, the resultant force of the second restoring force of the second elastic member and the first restoring force of the first elastic member is obtained. The spool receives the axial biasing force against the driving force. On the other hand, in the second region where the second elastic member is engaged with the sleeve stopper provided on the sleeve, the spool that receives the restriction of the bias due to the second restoring force is the first biasing force in the axial direction against the driving force. Receive restoration power. Therefore, at the boundary position between the first region and the second region, the urging force is stepped by switching between the combined action of the first restoring force and the second restoring force and the single action of the first restoring force. To change. As a result, it is possible to appropriately switch the required performance in each area.

  In addition, the location where the spool stopper moves in the first region and the second region is a location spaced radially from the sleeve and spaced circumferentially from the sleeve stopper. As a result, the spool stopper can realize switching between the resultant action and the single action in cooperation with the sleeve stopper without causing a sliding resistance as a movement resistance of the spool between the sleeve stopper and the sleeve stopper. . Therefore, with respect to the movement position of the spool with respect to the command value to the drive source, the hysteresis generated between the movement in the forward direction and the movement in the backward direction can be reduced in both the first region and the second region. . Accordingly, it is possible to suppress the responsiveness variation in the control valve.

  In another disclosed invention, the sleeve stopper protrudes radially inward from the inner peripheral portion (660) of the sleeve, thereby sandwiching a radial gap (682) between the spool stopper and the spool stopper. By projecting radially outward from the outer peripheral portion (700) of the sleeve, a portion spaced apart from the sleeve stopper with a circumferential clearance (724) while sandwiching the radial clearance (722) between the sleeve and the sleeve Moving.

  According to the present invention, the sleeve stopper that protrudes radially inward from the inner peripheral portion of the sleeve does not cause sliding resistance between the sleeve stopper and the spool that sandwiches the radial gap. Further, the spool stopper protruding outward in the radial direction from the outer periphery of the spool does not generate sliding resistance with the sleeve sandwiching the radial gap. Further, the spool stopper does not cause sliding resistance between the spool stopper and the sleeve stopper which is spaced apart from the moving position with a circumferential clearance. For these reasons, in both the first region and the second region, the spool movement resistance, and hence the hysteresis of the spool movement position, can be made as small as possible both when moving in the forward direction and when moving in the backward direction. Therefore, it becomes possible to raise the suppression degree of the responsiveness variation in a control valve.

  In yet another disclosed invention, the sleeve stoppers are provided in pairs in such a manner that a portion where the spool stopper moves is sandwiched in the circumferential direction.

  According to the present invention, the rotation of the spool stopper in the circumferential direction can be restricted by the pair of sleeve stoppers that sandwich the place where the spool stopper moves in the circumferential direction. Thereby, the spool stopper and the sleeve stopper can reliably maintain the state necessary for switching between the resultant action and the single action, that is, the state shifted in the circumferential direction. At the same time, even if the spool stopper is locked to the sleeve stopper on one side in the circumferential direction and restricted in rotation in the circumferential direction, the spool stopper is separated in the circumferential direction from the sleeve stopper on the opposite side in the circumferential direction. Can be reliably maintained. For this reason, it is possible to prevent an increase in the responsiveness variation generated in the control valve by the function while guaranteeing proper switching of the required performance for a long time by the rotation limiting function of the spool stopper.

It is a figure which shows the basic composition of the valve timing adjustment apparatus by one Embodiment, Comprising: It is the II sectional view taken on the line of FIG. It is the II-II sectional view taken on the line of FIG. It is a characteristic view for demonstrating the cam torque which acts on the valve timing adjustment apparatus of FIG. It is sectional drawing which shows the specific structure of the control valve of the valve timing adjustment apparatus of FIG. It is sectional drawing which shows another operation state of the control valve of FIG. It is sectional drawing which shows another operation state of the control valve of FIG. It is sectional drawing which shows another operation state of the control valve of FIG. It is sectional drawing which shows another operation state of the control valve of FIG. It is the IX-IX arrow directional view of FIG. It is a characteristic view which shows the characteristic of the control valve of FIG. It is a characteristic view which shows the characteristic of the control valve of FIG. It is a characteristic view which shows the characteristic of the control valve of FIG. It is sectional drawing which shows the modification 7 corresponding to FIG. FIG. 12 is a characteristic diagram showing Modification 7 corresponding to FIG. 11. It is a characteristic view which shows the conventional characteristic.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a valve timing adjusting apparatus 1 according to an embodiment of the present invention is mounted on an internal combustion engine of a vehicle. The device 1 adjusts the valve timing of the internal combustion engine by using the pressure of the hydraulic fluid that is the hydraulic fluid. The apparatus 1 adjusts the valve timing of the intake valve as the valve timing of the valve that opens and closes the camshaft 2 by transmission of crank torque from a crankshaft (not shown) in the internal combustion engine. The apparatus 1 includes a rotation mechanism system 10 and a control system 40.

(Rotation mechanism system)
First, the configuration of the rotation mechanism system 10 shown in FIGS. The rotation mechanism system 10 is installed in a transmission path that transmits crank torque from the crankshaft to the camshaft 2. The rotation mechanism system 10 includes a housing rotor 11 and a vane rotor 14.

  The metal housing rotor 11 is formed by fastening a rear plate 13 and a front plate 15 to both end portions of the shoe housing 12 in the axial direction. The shoe housing 12 includes a housing body 120, a plurality of shoes 121, 122, 123 and a sprocket 124. The cylindrical housing main body 120 is arranged so as to be aligned in the horizontal direction (left-right direction in FIG. 1) in a vehicle on a horizontal plane. The substantially fan-shaped shoes 121, 122, 123 protrude radially inward from locations spaced apart from each other in the rotation direction in the housing body 120. A storage chamber 20 is formed between the shoes 121, 122, 123 adjacent to each other in the rotational direction. The sprocket 124 is connected to the crankshaft via a timing chain (not shown). With this connection, while the internal combustion engine is rotating, crank torque is transmitted from the crankshaft to the sprocket 124, so that the housing rotor 11 rotates in a fixed direction (clockwise in FIG. 2) in conjunction with the crankshaft.

  The metal vane rotor 14 is accommodated coaxially in the housing rotor 11 and is in sliding contact with the rear plate 13 and the front plate 15 at both axial ends. The vane rotor 14 has a rotating shaft 140 and a plurality of vanes 141, 142, and 143. The cylindrical rotating shaft 140 is arranged in alignment in the horizontal direction (left-right direction in FIG. 1) in a vehicle on a horizontal plane, and is fixed coaxially to the cam shaft 2. With this fixing, the vane rotor 14 can rotate relative to the housing rotor 11 while being able to rotate in the same direction as the housing rotor 11 (clockwise in FIG. 2) in conjunction with the camshaft 2.

  The rotary shaft 140 of this embodiment is formed by coaxially fastening a boss 140b and a bush 140c on both sides in the axial direction of the shaft main body 140a. The boss 140b is in contact with the camshaft 2 through a central hole that passes through the annular rear plate 13. The bush 140 c protrudes out of the housing rotor 11 through a central hole that passes through the annular front plate 15.

  As shown in FIG. 2, the substantially fan-shaped vanes 141, 142, and 143 protrude outward in the radial direction from locations spaced apart from each other in the rotational direction in the shaft main body 140 a. Each of the vanes 141, 142, and 143 is accommodated in the corresponding accommodating chamber 20, and the corresponding accommodating chamber 20 is divided into both sides in the rotation direction. By such division, the vanes 141, 142, 143 partition the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28 into and out of the housing rotor 11 in the rotation direction. Specifically, an advance chamber 22 is formed between the shoe 121 and the vane 141, an advance chamber 23 is formed between the shoe 122 and the vane 142, and an advance chamber is formed between the shoe 123 and the vane 143. 24 is formed. On the other hand, a retardation chamber 26 is formed between the shoe 122 and the vane 141, a retardation chamber 27 is formed between the shoe 123 and the vane 142, and a retardation chamber 28 is formed between the shoe 121 and the vane 143. Is formed.

  As shown in FIGS. 1 and 2, the vane 141 accommodates the lock member 16 so that the rotation phase of the vane rotor 14 relative to the housing rotor 11 is locked to a predetermined lock phase so as to be fitted in the lock hole 130 of the rear plate 13. ing. At the same time, the vane 141 forms a lock release chamber 17 into which hydraulic oil is introduced in order to release the lock member 16 from the lock hole 130 and unlock the rotational phase.

  With the above configuration, the rotation mechanism system 10 introduces hydraulic oil into the advance chambers 22, 23, and 24 and discharges hydraulic oil from the retard chambers 26, 27, and 28 while unlocking the rotational phase by the lock member 16. The rotational phase changes in the advance direction. As a result, the valve timing is advanced. On the other hand, under the unlocking of the rotational phase, the rotational phase changes in the retarding direction by introducing hydraulic oil into the retarding chambers 26, 27, and 28 and discharging hydraulic fluid from the advance chambers 22, 23, 24. As a result, the valve timing is retarded. Furthermore, the hydraulic fluid is restricted from entering and exiting the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28 under the unlocking of the rotational phase. The hydraulic oil is confined in any of the chambers 26, 27, and 28. At this time, the rotation phase does not change depending on the hydraulic oil, and as a result, the valve timing is substantially maintained.

  Of the rotational phases that can be realized by the rotation mechanism system 10 in such valve timing adjustment, in the present embodiment, the restriction phase region that is regulated when the internal combustion engine is started, the maximum phase from the predetermined phase between the most retarded angle phase and the most advanced angle phase. An area up to the advance angle phase is set. In the present embodiment, in particular, the rotation phase when the lock is realized by the lock member 16, that is, the lock phase, is set as an intermediate phase for ensuring particularly optimum startability in the restricted phase region. According to such a setting, when the internal combustion engine is started, it is possible to suppress the situation where the amount of intake air into the cylinder is excessively reduced due to the delay in closing the intake valve, and to allow the start of the internal combustion engine.

(Control system)
Next, the configuration of the control system 40 shown in FIGS. The control system 40 controls the entry and exit of hydraulic oil in order to drive the rotation mechanism system 10. The control system 40 includes an advance main passage 41, advance branch passages 42, 43, 44, retard main passage 45, retard branch passages 46, 47, 48, lock release passage 49, main supply passage 50, and sub supply passage. 52, a drain recovery passage 54, a control valve 60 and a control circuit 96.

  The advance main passage 41 is formed along the inner periphery of the rotating shaft 140. The advance branch passages 42, 43, and 44 communicate with the corresponding advance chambers 22, 23, and 24 and the common advance main passage 41 by passing through the rotation shaft 140. The retard main passage 45 is formed along the inner peripheral portion of the rotating shaft 140. The retarded branch passages 46, 47, 48 penetrate through the rotating shaft 140 and communicate with the corresponding retarded chambers 26, 27, 28 and the common retarded main passage 45. The unlocking passage 49 communicates with the unlocking chamber 17 by passing through the rotation shaft 140.

  The main supply passage 50 communicates with the pump 4 as a supply source through the conveyance passage 3 by passing through the rotary shaft 140. Here, the pump 4 provided in the internal combustion engine is a mechanical pump driven by receiving crank torque. During the rotation of the internal combustion engine in which crank torque is generated, the pump 4 continuously discharges hydraulic oil sucked from a drain pan 5 serving as a drain recovery system to the transport passage 3. The conveyance passage 3 is formed through the camshaft 2 and a bearing (not shown) that supports the camshaft 2 and conveys hydraulic oil supplied from the pump 4 to the main supply passage 50.

  The sub supply passage 52 branches from the main supply passage 50 by passing through the rotating shaft 140. The sub supply passage 52 receives the supply hydraulic oil from the pump 4 through the main supply passage 50. Reed check valves (reed valves) 520 and 500 are provided in the middle portion of the sub supply passage 52 and in the middle portion of the main supply passage 50 on the side of the pump 4 with respect to the branch portion of the sub supply passage 52. (See also FIG. 4). Here, the sub check valve 520 prevents the hydraulic oil from flowing back to the main supply passage 50 side in the sub supply passage 52, and the main check valve 500 prevents the hydraulic oil from flowing to the pump 4 side in the main supply passage 50. Prevent backflow.

  As shown in FIG. 1, the drain collection passage 54 is formed outside the rotation mechanism system 10 and the cam shaft 2. The drain recovery passage 54 can discharge hydraulic oil toward the drain pan 5 that is open to the atmosphere.

  The control valve 60 reciprocates the spool 70 in the sleeve 66 shown in FIGS. 1 and 2 by using the driving force generated by energizing the driving source 90 and the elastic restoring force generated by the biasing adjustment structure 94. The spool valve is moved. The control valve 60 has an advance port 661, a retard port 662, a lock release port 663, a main supply port 664, a sub supply port 665, and a drain port 666. The advance port 661 communicates with the advance main passage 41, the retard port 662 communicates with the retard main passage 45, and the lock release port 663 communicates with the lock release passage 49. The main supply port 664 communicates with the main supply passage 50, the sub supply port 665 communicates with the sub supply passage 52, and the pair of drain ports 666 communicate with the drain recovery passage 54. The control valve 60 switches the connection state between these ports 661, 662, 663, 664, 665, 666 according to the movement of the spool 70. By such switching, the control valve 60 controls the entering and exiting of the hydraulic oil to and from the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28 as described in detail later.

  The control circuit 96 shown in FIG. 1 is an electronic circuit mainly composed of, for example, a microcomputer, and is electrically connected to the drive source 90 and various electrical components (not shown) of the internal combustion engine. The control circuit 96 controls the operation of the internal combustion engine including energization to the drive source 90 according to the computer program stored in the internal memory.

(Cam torque)
Next, the cam torque transmitted from the cam shaft 2 to the vane rotor 14 will be described in detail. During rotation of the internal combustion engine, cam torque acts on the camshaft 2 due to a spring reaction force from the intake valve, and the cam torque is transmitted to the vane rotor 14. As illustrated in FIG. 3, the cam torque alternates between a negative torque acting on the housing rotor 11 in the advance direction and a positive torque acting on the housing rotor 11 in the retard direction. Regarding the cam torque of the present embodiment, the peak torque T + of the positive torque is larger than the peak torque T− of the negative torque due to the friction between the camshaft 2 and its supporting bearing, and the average torque Tave thereof. Is biased toward the positive torque side. Therefore, during rotation of the internal combustion engine, the vane rotor 14 is biased biased toward the retard direction with respect to the housing rotor 11 on average by the cam torque transmitted from the cam shaft 2.

(Biasing structure)
Next, a biasing structure for biasing the vane rotor 14 toward the lock phase will be described in detail. As shown in FIG. 1, the front plate 15 is provided with a first locking pin 150. The first locking pin 150 is formed in a cylindrical shape protruding from the front plate 15 toward the outside of the housing rotor 11, and is arranged eccentrically and substantially parallel to the rotation center line O common to the rotors 11 and 14. .

  An arm 140d and a second locking pin 140e are provided at a location protruding from the housing rotor 11 in the bush 140c. The arm 140 d is formed in a flat plate shape substantially parallel to the front plate 15. The second locking pin 140e is formed in a columnar shape protruding from the arm 140d toward the front plate 15, and is arranged eccentrically and substantially parallel to the rotation center line O. The second locking pin 140e is eccentric from the rotation center line O by substantially the same distance as the first locking pin 150, and deviates from the rotation locus of the first locking pin 150 in the direction along the rotation center line O. Is arranged.

  An assist spring 18 is disposed on the outer peripheral side of the bush 140c between the front plate 15 and the arm 140d. The assist spring 18 is a spiral spring formed by winding a metal wire on substantially the same plane, and the center of the spiral is aligned with the rotation center line O. The end portion on the inner peripheral side of the assist spring 18 is wound around the outer peripheral portion of the bush 140c to form a winding portion 180. The outer peripheral side end of the assist spring 18 is bent in a U shape to form a locking portion 181. The locking portion 181 can be locked by a pin corresponding to the rotational phase of the first locking pin 150 and the second locking pin 140e.

  With the above configuration, the locking portion 181 is locked by the first locking pin 150 when the rotation phase changes in the retarding direction relative to the lock phase. At this time, since the second locking pin 140e is separated from the locking portion 181, the vane rotor 14 that receives the restoring force of the assist spring 18 is biased toward the locking phase in the advance direction. Here, the restoring force of the assist spring 18 is set to be larger than the average value of the cam torque biased in the retarding direction. On the other hand, the locking portion 181 is locked by the second locking pin 140e when the rotation phase changes in the advance direction from the lock phase. At this time, since the first locking pin 150 is separated from the locking portion 181, the biasing of the vane rotor 14 by the assist spring 18 is limited.

(Lock structure)
Next, a lock structure for locking the rotation phase will be described in detail. As shown in FIGS. 1 and 2, the rear plate 13 has a restriction hole 131 together with a lock hole 130. The restriction hole 131 is formed in a bottomed groove shape extending along the rotation direction and closed at both ends. The lock hole 130 is formed in the shape of a bottomed cylindrical hole opened on the bottom surface of the end portion in the advance direction of the restriction hole 131 (see also FIG. 4).

  The vane 141 has an accommodation hole 141 a for accommodating the cylindrical lock member 16. The accommodation hole 141a can guide the lock member 16 in the axial direction by passing through the vane 141 in the axial direction substantially parallel to the rotation center line O. The accommodation hole 141a faces the restriction hole 131 in the axial direction in the restriction phase region, and particularly faces the lock hole 130 in the axial direction in the lock phase. A lock spring 19 is accommodated coaxially with the lock member 16 in the accommodation hole 141a. The lock spring 19 is a metal compression coil spring, and is interposed between the retainer 141 b fixed to the vane 141 and the lock member 16. The lock spring 19 is compressed and elastically deformed between the retainer 141b and the lock member 16, thereby generating a restoring force. The lock member 16 that receives this restoring force is biased toward the rear plate 13 side. Furthermore, on the side opposite to the lock spring 19 with the lock member 16 sandwiched in the axial direction, a lock release chamber 17 is formed by the accommodation hole 141a. The lock member 16 is movable to the side opposite to the rear plate 13 against the restoring force of the lock spring 19 by receiving the pressure of the hydraulic oil introduced into the lock release chamber 17.

  With the above configuration, when the hydraulic oil is discharged from the lock release chamber 17 with the lock member 16 detached from both the restriction hole 131 and the lock hole 130, the lock member 16 moves to the rear plate 13 side. , Enters the restriction hole 131. As a result, the rotational phase is regulated in the regulation phase region. Furthermore, when the rotation phase reaches the lock phase due to the restoring force of the assist spring 18 and the cam torque under the restriction, the lock member 16 moves from the restriction hole 131 to the rear plate 13 and is fitted into the lock hole 130. To do. As a result, the rotation phase is locked to the lock phase, so that the adjustment of the valve timing according to the rotation phase is limited.

  On the other hand, when hydraulic oil of a predetermined pressure or higher is introduced into the lock release chamber 17 with the lock member 16 fitted into the lock hole 130 through the restriction hole 131, the lock member 16 moves to the opposite side to the rear plate 13. It moves and detaches from both holes 131 and 130. As a result, since the restriction and lock of the rotational phase are released, the valve timing can be freely adjusted according to the rotational phase.

(Control valve)
Next, the detailed structure of the control valve 60 will be described. In the control valve 60 shown in FIGS. 1 and 4, the metal sleeve 66 is formed in a bottomed cylindrical shape and is coaxially built across the rotating shaft 140 and the cam shaft 2. With such a built-in configuration, the sleeve 66 is disposed so as to be aligned in the horizontal direction (left-right direction in FIGS. 1 and 4) in a horizontal plane vehicle. The sleeve 66 has a male screw-like fixing portion 667 that is screwed and fixed to the camshaft 2 on the bottom side. Further, the sleeve 66 has an annular flange-shaped flange portion 668 on the opening side for sandwiching the rotation shaft 140 between the sleeve 66 and the cam shaft 2. The sleeve 66 has one drain port 666, an advance port 661, a main supply port 664, a retard port 662, a lock release port 663, an auxiliary supply port 665, and the other drain port 666 from the opening side in the axial direction to the bottom side. It is formed in this order toward.

  In the control valve 60, the metal spool 70 is formed in a bottomed cylindrical shape, and is slidably supported coaxially by a sleeve 66 from the outside in the radial direction perpendicular to the rotation center line O as a movable line. With such a support form, the spool 70 can be reciprocated in the axial direction along the rotation center line O by being arranged in alignment in the horizontal direction (left and right direction in FIGS. 1 and 4) in a vehicle on a horizontal plane. It has become. Therefore, in this embodiment, as shown in FIGS. 4 to 8, the direction in which the spool 70 heads toward the bottom side of the sleeve 66 in the axial direction is defined as the forward direction Dg, while the spool 70 in the axial direction has the sleeve 66. A direction toward the opening side is defined as a backward direction Dr.

  As shown in FIGS. 4 to 9, the spool 70 has a cylindrical hole-like communication passage 705 extending in the axial direction. The communication passage 705 forms an opening 705 a at each axial end of the spool 70 (that is, the opening-side end and the bottom-side end). These openings 705a can communicate with the respective drain ports 666 regardless of the movement position of the spool 70. In addition to the opening 705a, the communication passage 705 forms an opening 705b in the intermediate portion in the axial direction of the spool 70 shown in FIGS. The opening 705b can communicate or block with respect to at least one of the retard port 662 and the lock release port 663 according to the moving position of the spool 70.

  Further, the spool 70 has a throttle portion 706 in order to reduce the flow amount of hydraulic oil flowing between the advance port 661 and the main supply port 664 at a predetermined movement position shown in FIGS. In addition, it is good also as a structure which restrict | squeezes the distribution | circulation amount by making the outer diameter of the outer peripheral surface of the aperture | diaphragm | squeeze part 706 smaller than the internal diameter of the inner peripheral surface of the sleeve 66, and forming a clearance gap between these peripheral surfaces. Alternatively, although not shown in the drawings, the flow rate can be reduced by sliding the inner peripheral surface of the sleeve 66 and the outer peripheral surface of the throttle portion 706 by fitting and shortening the seal length of the sliding interface. Good.

  With the above configuration, when the spool 70 has moved to the lock region Rl in FIG. 10A, the advance port 661 is connected to the main supply port 664 as shown in FIGS. With this connection form, the hydraulic fluid supplied from the pump 4 is introduced into the advance chambers 22, 23, 24 through the passages 3, 50, 41, 42, 43, 44. At this time, the amount of hydraulic oil introduced into the advance chambers 22, 23, 24 is throttled by the throttle unit 706. In addition, the retard port 662 is connected to each drain port 666 via the passage 705 when the spool 70 is moved to the lock region Rl. With this connection form, the hydraulic oil in the retard chambers 26, 27, 28 is discharged to the drain pan 5 through the passages 46, 47, 48, 45, 54. Further, when the spool 70 is moved to the lock region Rl, the lock release port 663 is connected to each drain port 666 via the passage 705. With this connection configuration, the hydraulic oil in the lock release chamber 17 is discharged to the drain pan 5 through the passages 49 and 54.

  In a state where the spool 70 has moved to the advance angle region Ra of FIG. 10A arranged in the forward direction Dg with respect to the lock region Rl, the advance port 661 is connected to the main supply port 664 as shown in FIG. With this connection form, the hydraulic fluid supplied from the pump 4 is introduced into the advance chambers 22, 23, 24 through the passages 3, 50, 41, 42, 43, 44. Further, when the spool 70 is moved to the advance angle area Ra, the retard port 662 is connected to each drain port 666 via the passage 705. With this connection form, the hydraulic oil in the retard chambers 26, 27, 28 is discharged to the drain pan 5 through the passages 46, 47, 48, 45, 54. Further, when the spool 70 is moved to the advance angle region Ra, the lock release port 663 is connected to the sub supply port 665. With this connection form, the supply hydraulic oil from the pump 4 is introduced into the lock release chamber 17 through the passages 3, 50, 52, and 49.

  When the spool 70 is moved to the holding region Rh in FIG. 10A arranged in the forward direction Dg with respect to the advance angle region Ra, as shown in FIG. 7, the advance port 661 and the retard port 662 are not It is also blocked for the port. With such a blocking mode, hydraulic oil is retained in the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28. Further, when the spool 70 is moved to the holding region Rh, the lock release port 663 is connected to the sub supply port 665. With this connection configuration, the supply hydraulic oil from the pump 4 is introduced into the lock release chamber 17 through the passages 3, 50, 52, and 49.

  In a state where the spool 70 has moved to the retard angle region Rr of FIG. 10A aligned in the forward direction Dg with respect to the holding region Rh, the advance port 661 is connected to each drain port 666 via the passage 705 as shown in FIG. Connected. With this connection form, the hydraulic oil in the advance chambers 22, 23, 24 is discharged to the drain pan 5 through the passages 42, 43, 44, 41, 54. Further, the retard port 662 is connected to the main supply port 664 when the spool 70 is moved to the retard region Rr. With this connection form, the hydraulic fluid supplied from the pump 4 is introduced into the retarding chambers 26, 27, 28 through the passages 3, 50, 45, 46, 47, 48. In addition, the lock release port 663 is connected to the sub supply port 665 when the spool 70 is moved to the retard angle region Rr. With this connection form, the supply hydraulic oil from the pump 4 is introduced into the lock release chamber 17 through the passages 3, 50, 52, and 49.

  In particular, in each of the regions R1, Ra, and Rr shown in FIGS. 4 to 6 and 8, one drain port 666 formed by the opening of the sleeve 66 (hereinafter, this one drain port 666 is referred to as a drain port 666a). On the other hand, the hydraulic oil heading to the drain pan 5 is discharged. Therefore, the discharged hydraulic fluid flows between the inner peripheral portion 660 of the sleeve 66 and the outer peripheral portion 700 of the spool 70 at the drain port 666.

(Drive structure)
Next, the drive structure of the control valve 60 will be described in detail. As shown in FIG. 1, the drive source 90 is an electromagnetic solenoid that operates in response to energization, and is fixed to a fixed node such as a chain cover in the internal combustion engine. The drive source 90 has a metal drive shaft 91 formed in a rod shape. The drive shaft 91 is disposed coaxially with the elements 66 and 70 on the side opposite to the bottom of the sleeve 66 across the spool 70 in the axial direction. The drive shaft 91 is always in contact with the spool 70 by entering the drain port 666 a formed by the opening of the sleeve 66. The drive source 90 configured as described above causes the energizing current controlled as the command value to flow from the control circuit 96 to the solenoid coil (not shown), so that the spool 70 is moved in the forward direction Dg of FIGS. Press. Due to such pressing, the driving source 90 applies a driving force in the forward direction Dg according to the energization current from the control circuit 96 from the driving shaft 91 to the spool 70.

  As shown in FIG. 1, the urging adjustment structure 94 has a sleeve stopper 680, a spool stopper 72, a first urging force to adjust the urging force that urges the spool 70 in the axial direction against the driving force of the driving source 90. One elastic member 80 and a second elastic member 82 are provided.

  As shown in FIGS. 4 and 9, the sleeve stopper 680 is provided in a drain port 666 a that forms an opening in the sleeve 66. Four sleeve stoppers 680 of this embodiment are formed by metal snap rings 68 provided on the drain port 666a. Specifically, the snap ring 68 is configured such that the sleeve stopper 680 is integrated with the ring main body 681. The ring main body 681 is formed in a partial annular shape and is coaxially fixed to the cylindrical main body of the sleeve 66, thereby forming the inner peripheral portion 660 of the sleeve 66 together with the cylindrical main body. Each sleeve stopper 680 protrudes inward in the radial direction from a portion spaced in the circumferential direction around the rotation center line O in the ring main body 681 in which the inner peripheral portion 660 is formed. Each protruding piece-like sleeve stopper 680 has a protruding height in the radial direction that does not reach the spool 70 in any of the regions Rl, Ra, Rh, Rr shown in FIGS. Each sleeve stopper 680 having such a protruding height can be separated from the spool 70 in the radial direction in all the regions Rl, Ra, Rh, Rr by sandwiching the radial gap 682 between the spool 70.

  As shown in FIGS. 4 and 9, the spool stopper 72 is provided at the opening-side end portion that enters the drain port 666 a in the spool 70. Two spool stoppers 72 of the present embodiment are formed so as to protrude from the spool two-surface width portion 702 of the spool 70. Specifically, the spool two-surface width portion 702 is formed in a plate shape having a two-surface width extending along a predetermined radial direction (vertical direction in FIG. 9) and the axial direction. Each spool stopper 72 protrudes radially outward from both radial edge portions (hereinafter referred to as two-face width edge portions) 702 a forming the outer peripheral portion 700 in the spool two-face width portion 702. Each spool stopper 72 is formed in a projecting piece shape having a two-surface width that continues from the integral spool two-surface width portion 702 in the backward direction Dr. Each spool stopper 72 has a protruding height in the radial direction that does not reach the sleeve 66 in any of the regions Rl, Ra, Rh, Rr shown in FIGS. The spool stoppers 72 having such protruding heights can be separated from the sleeve 66 in the radial direction in all regions Rl, Ra, Rh, and Rr by sandwiching a radial gap 722 continuous in the circumferential direction with the sleeve 66. It has become.

  Here, in each of the regions Rl, Ra, Rh, Rr, at least one of the spool stopper 72 shown on the upper side in FIGS. 4 and 9 and the two-sided width edge portion 702a continuous with the two sleeves is paired on the upper side. The part U sandwiched in the circumferential direction by the stopper 680 is moved. At this pinched portion U, at least one of the spool stopper 72 and the two-sided width edge portion 702a is separated from each sleeve stopper 680 on both sides in the circumferential direction with a circumferential clearance 724 therebetween. On the other hand, in each of the regions Rl, Ra, Rh, Rr, at least one of the spool stopper 72 shown on the lower side in FIG. 9 and the two-sided width edge portion 702a continuous with the two sleeves forms a pair on the lower side. The part L sandwiched in the circumferential direction by the stopper 680 is moved. At the pinched portion L, at least one of the spool stopper 72 and the two-sided width edge portion 702a is separated from each sleeve stopper 680 on both sides in the circumferential direction with a circumferential gap 724 therebetween.

  Thus, in this embodiment, two pairs of sleeve stoppers 680 are provided so as to sandwich the separate portions U and L in the circumferential direction for each pair. Further, in particular, the spool stoppers 72 that move in the locations U and L in the regions Ra, Rh, and Rr shown in FIGS. 6 to 8 maintain the form of being sandwiched in the circumferential direction by a pair of sleeve stoppers 680, respectively. ing.

  As shown in FIGS. 4 and 9, the spool 70 has a spool engaging portion 704 that is engaged by each pair of sleeve stoppers 680. The spool engaging portion 704 is formed in an annular surface shape facing the backward direction Dr in the spool 70. The spool engaging portion 704 is exposed to the space portion 703 where the spool two-surface width portion 702 is not formed in the spool 70, so that the spool engaging portion 704 is positioned in the forward direction Dg with respect to each spool stopper 72 and the spool two-surface width portion 702. Yes. From the above configuration, each pair of sleeve stoppers 680 engages with the spool engaging portion 704 of the spool 70 that has reached the moving end R0 (see also FIGS. 10 and 11) in the backward direction Dr of the lock region R1 shown in FIG. Thus, the movement of the spool 70 in the backward direction Dr can be stopped.

  On the other hand, the sleeve 66 has a sleeve engaging portion 669 at a position located in the forward direction Dg with respect to each pair of sleeve stoppers 680. The sleeve engaging portion 669 is formed in an annular surface shape facing the backward direction Dr in the sleeve 66. Here, in the advance angle region Ra shown in FIG. 6, each spool stopper 72 moves in the forward direction Dg rather than each pair of sleeve stoppers 680. Therefore, in the advance angle region Ra, each spool stopper 72 is closer to the sleeve engaging portion 669 in the forward direction Dg than each pair of sleeve stoppers 680. The same applies to the holding region Rh shown in FIG. 7 and the retarding region Rr shown in FIG. On the other hand, in the lock region Rl shown in FIGS. 4 and 5, each spool stopper 72 moves in the backward direction Dr rather than each pair of sleeve stoppers 680. Therefore, in the lock region Rl, the spool stoppers 72 are separated from the sleeve engaging portions 669 in the backward direction Dr with respect to the pair of sleeve stoppers 680. That is, in the lock region Rl, each pair of sleeve stoppers 680 positioned in the forward direction Dg with respect to each spool stopper 72 is in a state of being close to the sleeve engaging portion 669.

  As shown in FIG. 4, the first elastic member 80 is a metal grinding end type compression coil spring, and is accommodated coaxially in the sleeve 66. The first elastic member 80 is interposed between the bottom of the sleeve 66 and the opening of the spool 70. The first elastic member 80 generates the first restoring force F1 by compressing and elastically deforming between the sleeve 66 and the spool 70 in any of Rl, Ra, Rh, Rr shown in FIGS. . The spool 70 that receives the first restoring force F1 is biased in the backward direction Dr that is opposite to the forward direction Dg.

  As shown in FIGS. 4 and 9, the second elastic member 82 is a metal grinding end type compression coil spring, and is accommodated coaxially in the sleeve 66. One end of the second elastic member 82 is always engaged with the sleeve engaging portion 669. The other end of the second elastic member 82 can be engaged with each spool stopper 72 or each pair of sleeve stoppers 680 in accordance with the movement position of the spool 70 shown in FIGS.

  Specifically, in the advance angle region Ra shown in FIG. 6, the second elastic member 82 engages with each spool stopper 72 adjacent to the sleeve engaging portion 669. By this engagement, the second elastic member 82 is compressed and elastically deformed between each spool stopper 72 and the sleeve engaging portion 669 to generate a second restoring force F2. The spool 70 that receives the second restoring force F2 together with the first restoring force F1 is biased in the restoring direction Dr opposite to the forward direction Dg. That is, the resultant force of the first restoring force F1 and the second restoring force F2 as shown in FIG. 11 acts on the spool 70 at this time as an urging force in the backward direction Dr against the driving force in the forward direction Dg. Become. This also applies to the holding region Rh shown in FIG. 7 and the retardation region Rr shown in FIG.

  On the other hand, in the lock region Rl shown in FIGS. 4 and 5, the second elastic member 82 is engaged with each pair of sleeve stoppers 680 that are in a proximity state with respect to the sleeve engaging portion 669. The engagement with each separated spool stopper 72 is released. Due to such disengagement, the spool 70 is restricted from being biased by the second restoring force F2 while receiving the first restoring force F1. That is, the first restoring force F1 acts solely on the spool 70 at this time as an urging force in the reverse direction Dr against the driving force in the forward direction Dg, as shown in FIG.

  Due to the above operating characteristics, at the boundary position between the advance angle region Ra and the lock region Rl aligned in the axial direction, the single action of the first restoring force F1, the first restoring force F1 and the second restoring force F1, as shown in FIGS. The resultant action of the restoring force F2 is switched. As a result of such switching, the urging force in the backward direction Dr acting on the spool 70 against the driving force in the forward direction Dg changes in a step shape. Here, the change width W of the urging force shown in FIG. 11 is set larger than the predicted width related to the product variation of the driving force that the driving source 90 acts on the spool 70 at the boundary position between the regions Ra and Rl. By such setting, it is possible to surely balance the driving force within the predicted width with the urging force within the change width W. Therefore, among the movement positions determined by the balance between the driving force and the urging force (that is, the intersection of the one-dot chain line graph and the solid line graph in FIG. 11), the product position variation in the driving force is not possible for the boundary position between the regions Ra and Rl. It does not depend on it, but depends only on the product variation of the urging force.

  From the above description, in the present embodiment, the advance angle region Ra corresponds to the first region, and the lock region Rl corresponds to the second region. It can also be considered that the regions Ra, Rh, Rr located in the forward direction Dg together correspond to the first region rather than the lock region Rl corresponding to the second region.

(Valve timing adjustment operation)
Next, the valve timing adjustment operation by the valve timing adjustment device 1 will be described.

(1) Locking operation In the internal combustion engine, the control circuit 96 controls the energization to the drive source 90 at the time of rotation stop when the hydraulic oil supply pressure from the pump 4 is low, at the time of starting, at the time of idle operation, etc. Then, the spool 70 is moved to the lock region Rl in FIG. 4 or FIG. In this lock region Rl, a small flow rate of hydraulic oil is introduced into the advance chambers 22, 23, 24, the hydraulic oil is discharged from the retard chambers 26, 27, 28, and the hydraulic oil is discharged from the lock release chamber 17. The rotation phase is locked at the lock phase. In particular, even when the rotation of the internal combustion engine where the supply of hydraulic oil from the pump 4 and the generation of the driving force by the driving source 90 is stopped, the first restoring force F1 as the urging force acts on the spool 70 alone. With this single action, the spool 70 reaches the moving end R0 in the backward direction Dr of the lock region Rl and is stopped by each pair of sleeve stoppers 680, thereby allowing the hydraulic oil to be discharged from the lock release chamber 17. At this time, when the cam phase acts on the vane rotor 14 together with the restoring force of the assist spring 18 directed in the advance direction, the lock member 16 enters the restriction hole 131 and rotates when the rotation phase reaches the restriction phase region. The phase is restricted within the region. As a result, the lock member 16 can be easily fitted into the lock hole 130 at the lock phase within the regulation phase region, so that the lock phase can be reliably locked to the lock phase until the rotation of the internal combustion engine completely stops. ing.

(2) Advance angle operation In an internal combustion engine, when an operating condition such as the actual phase of the rotational phase is in a retarded angle direction with respect to the target phase, the control circuit 96 controls energization to the drive source 90. Thus, the spool 70 is moved to the advance angle region Ra in FIG. In this advance angle region Ra, a large flow rate of hydraulic oil is introduced into the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28 under the unlocking of the rotational phase by introducing the hydraulic oil into the lock release chamber 17. Hydraulic oil is discharged from As a result, the rotational phase rapidly changes in the advance direction, so that it is possible to improve the advance response of the valve timing. In particular, even if the spool 70 in the advance angle region Ra approaches the lock region Rl due to variations or fluctuations in the energization current, the step force change between the regions Ra and Rl occurs. It is difficult to cross the boundary position.

(3) Holding operation In the internal combustion engine, when an operating condition such as the actual phase of the rotational phase is within an allowable deviation with respect to the target phase is satisfied, the control circuit 96 controls the energization to the drive source 90, thereby controlling the spool 70. Is moved to the holding region Rh in FIG. In the holding region Rh, the hydraulic oil is retained in any of the advance chambers 22, 23, 24 and the retard chambers 26, 27, 28 under the unlocking of the rotational phase by introducing the hydraulic oil into the lock release chamber 17. As a result, the change of the rotation phase is regulated within the range of fluctuation due to the influence of the cam torque, so that it is possible to ensure the retention of the valve timing.

(4) Delayed angle operation In the internal combustion engine, when an operating condition such as the actual phase of the rotational phase is in the advance direction with respect to the target phase relative to the target phase is satisfied, the control circuit 96 controls energization to the drive source 90. As a result, the spool 70 is moved to the retardation region Rr in FIG. In this retarding region Rr, under the unlocking of the rotational phase by introducing the working oil into the unlocking chamber 17, the introduction of a large amount of hydraulic fluid into the retarding chambers 26, 27, 28 and the advance chambers 22, 23, 24. Hydraulic oil is discharged from As a result, the rotational phase rapidly changes in the retarding direction, so that it is possible to improve the retarding response of the valve timing.

(Function and effect)
The effects of the apparatus 1 described above will be described below.

  According to the device 1, in the advance angle region Ra where the second elastic member 82 is engaged with the spool stopper 72 provided on the spool 70, the second restoring force F <b> 2 of the member 82 and the first restoring force of the first elastic member 80. The spool 70 receives the resultant force with F1 as an axial biasing force against the driving force. On the other hand, in the lock region Rl in which the second elastic member 82 is engaged with the sleeve stopper 680 provided on the sleeve 66, the spool 70 which is restricted by the bias by the second restoring force F2 is in the axial direction against the driving force. Receives the first restoring force F1 as an urging force. Therefore, at the boundary position between the regions Ra and Rl, the resultant force of the first restoring force F1 and the second restoring force F2 and the single action of the first restoring force F1 are switched, so that the urging force is stepped. To change. As a result, it is possible to appropriately switch the required performance in each of the regions Ra and Rl.

  Moreover, the locations where the spool stopper 72 moves in the regions Ra and Rl are the locations U and L that are spaced apart from the sleeve 66 in the radial direction and spaced apart from the sleeve stopper 680 in the circumferential direction. As a result, the spool stopper 72 does not cause a sliding resistance as a movement resistance of the spool 70 between the sleeve 66 and the sleeve stopper 680, and can switch between the resultant action and the single action together with the sleeve stopper 680. Can be realized. Therefore, as shown in FIG. 12, with respect to the movement position of the spool 70 with respect to the command value to the drive source 90, the hysteresis generated between the movement in the forward direction Dg and the movement in the backward direction Dr. It can be made small in both Rl. Therefore, it is possible to suppress the responsiveness variation in the control valve 60.

  Here, according to the device 1, the sleeve stopper 680 protruding radially inward from the inner peripheral portion 660 of the sleeve 66 does not generate sliding resistance with the spool 70 with the radial gap 682 interposed therebetween. Further, the spool stopper 72 protruding outward in the radial direction from the outer peripheral portion 700 of the spool 70 does not generate sliding resistance with the sleeve 66 with the radial gap 722 interposed therebetween. At the same time, the spool stopper 72 does not generate sliding resistance between the spool stopper 72 and the sleeve stopper 680 which is spaced apart from the locations U and L where the spool stopper 72 moves. For these reasons, the movement resistance of the spool 70, and hence the hysteresis of the spool movement position, in both the regions Ra and Rl can be made as small as possible both when moving in the forward direction Dg and when moving in the backward direction Dr. Therefore, it is possible to increase the degree of suppression of responsiveness variation in the control valve 60.

  Furthermore, according to the apparatus 1, the hydraulic fluid that flows between the inner peripheral portion 660 of the sleeve 66 and the outer peripheral portion 700 of the spool 70 in accordance with the hydraulic oil input / output control is between the stopper 680 and the spool 70, and between the stopper 72 and the sleeve 66. And between the stoppers. According to this, it is possible to ensure the necessary flow amount of the hydraulic oil in the input / output control using the gaps 682, 722, 724 for preventing the sliding resistance. Therefore, not only the responsiveness variation caused by the hysteresis of the spool movement position but also the responsiveness variation caused by fluctuations in the flow rate of the hydraulic oil in the inlet / outlet control can be suppressed by the control valve 60.

  Furthermore, according to the device 1, the rotation of the spool stopper 72 in the circumferential direction is restricted by the pair of sleeve stoppers 680 sandwiching the locations U and L to which the spool stopper 72 moves in the circumferential direction. Thereby, the spool stopper 72 and the sleeve stopper 680 can reliably maintain the state necessary for switching between the resultant action and the single action, that is, the state shifted in the circumferential direction. At the same time, even if the spool stopper 72 is locked to the sleeve stopper 680 on one side in the circumferential direction and restricted in rotation in the circumferential direction, the spool stopper 72 is circumferentially moved between the spool stopper 72 and the sleeve stopper 680 on the opposite side in the circumferential direction. Can be reliably maintained. For this reason, it is possible to suppress an increase in responsiveness variation generated in the control valve 60 by this function while ensuring proper switching of the required performance for a long time by the rotation limiting function of the spool stopper 72.

  In addition, according to the apparatus 1, the plurality of pairs of sleeve stoppers 680 sandwich the portions U and L to which the respective spool stoppers 72 move for each pair in the circumferential direction. According to this, since the rotation limiting function of the spool stopper 72 can be exhibited at a plurality of locations in the circumferential direction, it is possible to reliably ensure proper switching of required performance for a long time.

  In addition, according to the apparatus 1, the spool double face width portion 702 that is continuous in the axial direction from the double face width spool stopper 72 in the spool 70 is also located at the locations U and L sandwiched in the circumferential direction by the pair of sleeve stoppers 680. To move. According to this, even if the axial size of the spool stopper 72 is reduced, the same rotation limiting function as that by the spool stopper 72 can be exhibited by using the spool two-surface width portion 702. Therefore, the rotation limiting function after achieving such downsizing can achieve an appropriate switching guarantee of the required performance for a long time, and can suppress an increase in responsiveness variation generated in the control valve 60 by the function. .

  In addition, in the advance angle region Ra of the apparatus 1, the first restoring force F1 and the second restoring force that are generated in the backward direction Dr of the axial direction as the biasing force against the driving force of the forward direction Dg in the axial direction. The spool 70 receives the resultant force of F2. On the other hand, in the lock region Rl where the urging by the second restoring force F2 is restricted, the spool 70 receives the first restoring force F1 generated in the backward direction Dr as the urging force against the driving force in the forward direction Dg. According to these, since the resultant action and the single action can be reliably switched at the boundary position between the regions Ra and Rl, the step change of the urging force against the driving force can be made to appear as a firm one. Therefore, it is possible to increase the reliability with respect to the appropriate switching effect of the required performance.

  In addition, according to the device 1, the spool 70 that has reached the moving end R0 in the backward direction Dr of the lock region Rl is connected to the sleeve stopper 680 by the spool engaging portion 704 located in the forward direction Dg rather than the spool stopper 72. By engaging, the movement in the backward direction Dr can be stopped. According to this, the moving end R0 in the backward direction Dr of the lock region Rl can be accurately set by using the sleeve stopper 680 for switching between the resultant action and the single action. Therefore, it is possible to avoid a situation in which the spool 70 protrudes in the backward direction Dr from the lock region Rl in the sleeve 66 and it becomes difficult to control the hydraulic oil in and out by the control valve 60.

  In addition to the above, according to the apparatus 1, one of the regions Ra and Rl for changing the rotational phase and the other for locking the rotational phase to an intermediate phase between the most advanced phase and the most retarded phase. A step-like change in the biasing force against the driving force can appear at the boundary position between them. Therefore, as the necessary performance to be switched according to the movement position of the spool 70, it is possible to appropriately switch between the performance necessary for the change of the rotation phase and the performance necessary for the locking at the intermediate phase.

(Other embodiments)
Although one embodiment of the present invention has been described above, the present invention is not construed as being limited to the embodiment, and can be applied to various embodiments without departing from the gist of the present invention. it can.

  Specifically, as a first modification, the boundary position between the regions Ra and Rh or the boundary between the regions Rh and Rr is determined with respect to a position where the biasing force that biases the spool 70 against the driving force of the driving source 90 is changed stepwise. The position may be set. Alternatively, as a second modification, any one of the regions Rl, Ra, Rh, and Rr may be further divided, and the step change position may be set at the boundary position of these divided regions.

  As a third modified example, the sleeve stopper 680 and the spool stopper 72 can be arranged in a form in which the numbers of the sleeve stopper 680 and the spool stopper 72 are set appropriately and are spaced apart from each other in the circumferential direction. For example, the locations U and L where one spool stopper 72 moves may be sandwiched between the pair of sleeve stoppers 680 in the circumferential direction. Alternatively, the locations U and L where one or two spool stoppers 72 move may be arranged on one side or both sides in the circumferential direction with respect to one sleeve stopper 680.

  As a fourth modification, the spool stopper 72 may be formed separately from the spool 70 such as the spool two-surface width portion 702 and attached to the spool 70. Further, as a fifth modification, the sleeve stopper 680 may be formed integrally with the sleeve 66.

  As a sixth modified example, the spool engaging portion 704 positioned in the forward direction Dg with respect to the spool stopper 72 is not provided, and the end surface in the backward direction Dr of the spool stopper 72 is engaged with the sleeve 66, whereby the spool 70 is restored. The movement in the direction Dr may be stopped.

  As a modified example 7, as shown in FIGS. 13 and 14, the second elastic force that urges the spool 70 in the forward direction Dg and generates a second restoring force F2 smaller than the first restoring force F1 in the advance angle region Ra. The member 82 may be adopted. In this case, in the lock region Rl corresponding to the first region, the urging force that urges the spool 70 against the driving force in the forward direction Dg is greater than the first restoring force F1 generated in the backward direction Dr. The resultant force is the second restoring force F2 generated in the small forward direction Dg. At the same time, at least in the advance angle region Ra corresponding to the second region, the urging force in the reverse direction Dr against the driving force in the forward direction Dg is the first restoring force F1 alone. Therefore, also in the case of the modified example 7, the same effect as that of the above-described embodiment can be exhibited by the joint of the sleeve stopper 680 and the spool stopper 72.

  As a modified example 8, a sleeve 66 that accommodates the spool 70 and the elastic members 80 and 82 may be incorporated in one of the elements 140 and 2 or may be disposed outside the elements 140 and 2. Moreover, as the modified example 9, the restriction hole 131 for setting the restriction phase region may not be provided.

  As a tenth modification, the lock phase that locks the rotational phase may be set to the most retarded phase or the most advanced angle phase. Moreover, as a modification 11 in this case, the biasing structure of the vane rotor 14 by the assist spring 18 may be omitted.

  As a modified example 12, the present invention may be applied to a device that adjusts the valve timing of an exhaust valve that is a valve, or a device that adjusts the valve timing of both an intake valve and an exhaust valve that are valves.

1 Valve timing adjusting device, 2 cam shaft, 10 rotation mechanism system, 11 housing rotor, 14 vane rotor, 22, 23, 24 advance chamber, 26, 27, 28 retard chamber, 40 control system, 60 control valve, 66 sleeve , 68 Snap ring, 70 Spool, 72 Spool stopper, 80 First elastic member, 82 Second elastic member, 90 Drive source, 94 Biasing adjustment structure, 96 Control circuit, 660 Inner circumference, 666a Drain port, 669 Joint part, 680 Sleeve stopper, 681 Ring body, 682, 722 Radial gap, 700 Outer peripheral part, 702 Spool two-sided width part, 702a Two-sided width edge part, 703 Space part, 704 Spool engaging part, 722 Radial gap 724, circumferential clearance, Dg forward direction, Dr reverse direction, F1 first restoring force, F2 second Restoring force, L, U location, O rotation center line, R0 moving end, Ra advance angle area, Rh holding area, Rl lock area, Rr retard angle area

Claims (9)

A valve timing adjusting device for adjusting a valve timing of a valve that opens and closes a camshaft (2) by torque transmission from a crankshaft in an internal combustion engine,
A housing rotor (11) that rotates in conjunction with the crankshaft;
The camshaft rotates in conjunction with the camshaft to partition the advance chambers (22, 23, 24) and the retard chambers (26, 27, 28) in the rotation direction in the housing rotor. A vane rotor (14) whose rotational phase with respect to the housing rotor changes in an advance direction or a retard direction by being introduced into the retard chamber;
A control valve for controlling the entry and exit of the working fluid into and from the advance chamber and the retard chamber by reciprocating the spool (70) accommodated in the sleeve (66) in the axial direction along the movable line (O). (60)
A driving source (90) for generating a driving force for driving the spool in the axial direction according to a command value;
An urging adjustment structure (94) for adjusting an urging force for urging the spool in the axial direction against the driving force;
A first region (Ra) and a second region (Rl) as regions in which the spool moves in the sleeve are set side by side in the axial direction,
The bias adjustment structure is
A sleeve stopper (680) provided on the sleeve;
A spool stopper (72) provided on the spool;
A first elastic member (80) housed in the sleeve and generating a first restoring force (F1) for urging the spool in the axial direction in the first region and the second region;
In the first region that is accommodated in the sleeve and engages with the spool stopper, the second restoring force (F2) that urges the spool in the axial direction is generated while the sleeve engages with the sleeve stopper. A second elastic member (82) in the second region, the second elastic member (82) being limited to the biasing of the spool by the second restoring force;
In the first region and the second region, the spool stopper is separated from the sleeve in the radial direction perpendicular to the movable line, and spaced from the sleeve stopper in the circumferential direction around the movable line (U, L ), The valve timing adjusting device characterized by moving. The sleeve stopper protrudes inward in the radial direction from the inner peripheral portion (660) of the sleeve, thereby sandwiching the radial gap (682) between the sleeve and the spool,
The spool stopper protrudes from the outer peripheral portion (700) of the spool to the outer side in the radial direction, so that the radial gap (722) is sandwiched between the spool stopper and the circumferential direction (700). The valve timing adjusting device according to claim 1, wherein the gap is moved with the gap (724) therebetween.   The valve timing adjusting device according to claim 2, wherein the hydraulic fluid flows between the inner peripheral portion of the sleeve and the outer peripheral portion of the spool in accordance with the control of the hydraulic fluid.   The valve timing adjusting device according to any one of claims 1 to 3, wherein the sleeve stoppers are provided in a pair so as to sandwich the portion where the spool stopper moves in the circumferential direction. . A plurality of the spool stoppers are provided,
The valve timing adjusting device according to claim 4, wherein a plurality of pairs of the sleeve stoppers are provided, and the portions where the different spool stoppers move are sandwiched in the circumferential direction for each pair. The spool forms a spool two-sided width portion (702) continuous in the axial direction from the spool stopper having a two-sided width,
6. The sleeve stopper pair according to claim 4, wherein the pair of sleeve stoppers is provided so as to sandwich at least one of the spool stopper and the spool two-surface width portion in the circumferential direction. Valve timing adjustment device. The drive source generates the drive force that drives the spool in the forward direction (Dg) of the axial direction,
The first elastic member and the second elastic member have the first restoring force and the second restoring force for urging the spool in a returning direction (Dr) opposite to the forward direction in the axial direction, respectively. The valve timing adjusting device according to any one of claims 1 to 6, wherein the valve timing adjusting device is generated. The spool has a spool engaging portion (704) positioned in the forward direction with respect to the spool stopper,
The sleeve stopper stops movement of the spool in the backward direction by engaging the spool engaging portion of the spool that has reached the backward movement end (R0) of the second region. 8. The valve timing adjusting device according to claim 7, wherein One of the first region and the second region is a region for changing the rotational phase,
The other of the first region and the second region is a region for locking the rotational phase to an intermediate phase between the most advanced angle phase and the most retarded angle phase. The valve timing adjusting device according to any one of the above.

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