JP2012122453A - Valve timing adjusting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten adjusting responsiveness of valve timing.SOLUTION: A spool 73 of a control valve 70 includes: a circulation path 110 connecting a delay angle control port 81 and an advance angle control port 80 in a mode A2 changing a rotation phase onto an advance angle side; a circulation checking valve 120 permitting only circulation of a hydraulic fluid flowing, from the port 81 to a port 80 side, through the circulation path 110 in the mode A2; and an advance angle drain path 112 connecting the port 81 and an advance angle drain port 85 in the mode A2. The spool 73 increases or decreases both a circulation area Fac held, between the path 110 opening toward the port 81 and the port 81, and a circulation area Fad held, between the path 112 opening toward the port 81 independently of the path 110 and the port 81, while a relation of the circulation area Fad smaller than the circulation area Fac is maintained by movement in a direction Da or a direction Dr in the mode A2.

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 that rotates in conjunction with a crankshaft and a vane rotor that rotates in conjunction with a camshaft is known. As one type of such device, Patent Document 1 discloses that the rotational phase of the vane rotor relative to the housing is advanced or retarded by introducing hydraulic fluid into the advance chamber or retard chamber divided in the rotation direction by the vane rotor in the housing. What is changed to the side is disclosed. The device of Patent Document 1 uses a control valve that controls the entry and exit of hydraulic fluid into and from the advance chamber and the retard chamber according to the movement position of the spool accommodated in the sleeve.

  Specifically, in the device of Patent Document 1, the sleeve of the control valve has an introduction port (retarding output port) for introducing hydraulic fluid into the retarding chamber when the rotational phase changes to the retarding side, and the retarding side. A discharge port (advance output port) through which hydraulic fluid is discharged from the advance chamber at the time of change is provided. Further, the sleeve has a supply port (input port) through which the working fluid supplied from the supply source (pump) flows to the introduction port side when the rotational phase changes to the retard side, and is opened to the atmosphere to discharge the working fluid. A drain port is provided.

  Further, in the device of Patent Document 1, a return passage (retarding connection passage) that connects between the discharge port and the introduction port when the rotational phase changes to the retard side, and a return passage is introduced from the discharge port to the spool of the control valve. A reflux check valve (retarded connection check valve) that allows only reflux of the working fluid flowing to the port side is provided. Further, the spool is provided with a drain passage (relay passage) that connects between the discharge port and the drain port when the rotational phase changes on the retard side.

  In such an apparatus of Patent Document 1, when the hydraulic phase supplied from the supply source to the supply port flows to the introduction port side, the discharge port is connected to the drain port that is opened to the atmosphere when the rotational phase changes to the retard side. It will be in the state connected via the channel | path. As a result, the reflux that flows from the introduction port to the discharge port side through the return passage is regulated by the return check valve, so that the hydraulic fluid is introduced into the retarded chamber through the introduction port and the drain connected to the discharge port. The hydraulic fluid is discharged from the advance chamber to the drain port through the passage. As a result of the above supply pressure operation, the rotational phase changes to the retard side, and valve timing adjustment according to the rotational phase is realized.

  Here, the control valve of the device of Patent Document 1 has another groove portion at a position shifted in the axial direction from the groove portion of the discharge port on the inner peripheral surface of the sleeve. As a result, when the rotational phase changes to the retard side, the return passage opens toward the formation groove portion and the separate groove portion of the discharge port, and the drain passage opens toward the separate groove portion, so that the opening portion of the return passage and The discharge port is connected to the drain port through another groove. As a result, the flow area of the working fluid is reduced between the formation groove of the discharge port and the opening of the reflux passage, and between the separate groove and the opening of the drain passage, so that the introduction port and the drain port from the discharge port It is possible to individually control the flow rate of the hydraulic fluid that flows to each side.

  In addition, in the apparatus of Patent Document 1, when the supply pressure of the hydraulic fluid from the supply source decreases due to a temperature rise or the like, the advance chamber is changed from the advance chamber to the retard chamber through the return passage when the rotational phase changes to the retard side. An operation of refluxing the working fluid occurs. Hereinafter, the reflux operation will be specifically described.

  In the recirculation operation, when the advance chamber tries to reduce the volume by the action of the variable torque, the working fluid in the advance chamber is pushed out to the recirculation passage through the discharge port. At this time, in the recirculation passage connected to the retarded chamber whose volume is expanded by the action of the variable torque via the introduction port, the recirculation flow to the introduction port side is allowed by the recirculation check valve, so that negative pressure is generated. The hydraulic chamber discharged from the advance chamber is sucked into the retard chamber, and the rotational phase changes to the retard side. Further, when the direction of the variable torque is reversed and the retarding chamber attempts to reduce the volume, the hydraulic fluid introduced into the retarding chamber before the reversal is pushed out to the return passage, but flows to the discharge port side in the return passage. Since the recirculation is regulated by the recirculation check valve, the return of the rotational phase to the advance side is suppressed.

  In such a recirculation operation, since the drain port connected to the discharge port via the drain passage is opened to the atmosphere, there is a concern about the intake of air in the retarded chamber in which a negative pressure is generated due to the volume expansion. If air is sucked into the retarding chamber, the elastic coefficient of the mixture of the air and the working fluid is apparently reduced, so that the vane rotor is violated and valve timing adjustment responsiveness is lowered. Therefore, it is desirable to suppress the intake of air by reducing the flow area between the opening of the drain passage and the separate groove portion than the flow area between the opening of the reflux passage and the groove forming the discharge port. .

Japanese Patent No. 4518149

  However, in the above-described reflux operation, in the apparatus of Patent Document 1, the formation groove portion of the discharge port is brought into a positive pressure state due to the inflow of the hydraulic fluid pushed out from the advance chamber, while the opening portion of the return passage facing the formation groove portion. In this case, the negative pressure in the retarding chamber propagates. In this way, the opening of the recirculation passage where negative pressure acts faces the other groove portion together with the opening of the drain passage that becomes atmospheric pressure by connection with the drain port opened to the atmosphere, so that negative pressure also acts on the other groove portion. It becomes easy. As a result, air sucked from the drain port through the drain passage into the other groove portion is further sucked into the retard chamber through the reflux passage, and there is a possibility that the valve timing adjustment responsiveness may be lowered due to the vane rotor rampage.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a valve timing adjusting device that improves valve timing adjustment responsiveness.

  The invention according to claim 1 is a valve timing adjusting device that adjusts the valve timing of a valve that opens and closes the camshaft by torque transmission from the crankshaft in an internal combustion engine, a housing that rotates in conjunction with the crankshaft, a cam Rotating phase with respect to the housing by rotating in conjunction with the shaft, partitioning the advance chamber and retard chamber in the rotation direction in the housing, and introducing the working fluid supplied from the supply source into the advance chamber or retard chamber A vane rotor that changes to an advance side or a retard side, and a control valve that controls entry and exit of hydraulic fluid into and from the advance chamber and the retard chamber according to the movement position of the spool accommodated in the sleeve, The sleeve includes an introduction port for introducing hydraulic fluid into one of the advance chamber and the retard chamber in the phase change mode for changing the rotation phase, and the advance chamber and the retard in the phase change mode. A discharge port through which the hydraulic fluid is discharged from the other side of the chamber, a supply port through which the hydraulic fluid supplied from the supply source flows to the introduction port in the phase change mode, and a drain port that is open to the atmosphere and discharges the hydraulic fluid The spool has a reflux passage connecting the discharge port and the introduction port in the phase change mode and a return of the working fluid flowing through the return passage from the discharge port to the introduction port in the phase change mode. On the other hand, it has a reflux check valve that regulates the reflux of the working fluid flowing through the return passage from the introduction port to the discharge port, and a drain passage that connects between the discharge port and the drain port in the phase change mode. In addition, in the phase change mode, by moving in the increasing direction as one of the axial directions or the decreasing direction as the other, The operation that is secured between the drain passage and the discharge port that opens independently of the reflux passage toward the discharge port, rather than the flow area of the hydraulic fluid that is secured between the reflux passage that opens and the discharge port. The distribution area of the liquid increases or decreases both of the distribution areas while maintaining a small relationship.

  In such a phase change mode of the invention, the return passage is connected from the discharge port to the introduction port side in accordance with the flow area of the working fluid secured between the return passage opening toward the discharge port and the discharge port. It is possible to control the flow rate of the working fluid that flows to (hereinafter, in the column of solution means, this flow area is referred to as “reflux area”). Further, in the phase change mode, the drain passage is circulated from the drain port to the drain port side according to the flow area of the hydraulic fluid secured between the drain passage opening toward the discharge port and the discharge port. The flow rate of the hydraulic fluid can be controlled (hereinafter, in the column of solution means, this flow area is referred to as “drain area”).

  In the phase change mode in which the hydraulic fluid supplied from the supply source to the supply port flows to the introduction port side, the discharge port is connected to a drain port that is opened to the atmosphere via a drain passage. As a result, when the supply pressure of the hydraulic fluid is high, the reflux flowing through the reflux passage from the introduction port to the discharge port is restricted by the reflux check valve, so that the hydraulic fluid passes through the introduction port and the advance chamber and It is introduced into one of the retarded chambers (hereinafter, in the column of solution means, such one is referred to as “introduction target chamber”). At the same time, the hydraulic fluid is discharged from the other of the advance chamber and the retard chamber to the drain port through the drain passage connected to the discharge port (hereinafter, the other is referred to as “discharge target chamber” in the column of solution means). . As a result of the above supply pressure operation, the rotational phase changes, and valve timing adjustment according to the rotational phase can be realized.

  On the other hand, when the supply pressure of the hydraulic fluid from the supply source decreases due to a temperature rise or the like, in the phase change mode, the return passage from one discharge target chamber to the other introduction target chamber of the advance chamber and the retard chamber A reflux operation occurs in which the working fluid is refluxed through. Specifically, in the recirculation operation, when the volume of the discharge target chamber is reduced by the action of the variable torque, the working fluid in the discharge target chamber is pushed out to the recirculation passage through the discharge port. At this time, in the recirculation passage connected via the introduction port to the introduction target chamber whose volume is expanded by the action of the variable torque, the recirculation flow to the introduction port is allowed by the recirculation check valve. In the introduced target chamber, the discharged working fluid is sucked from the discharge target chamber, and the rotation phase changes. Further, when the direction of the variable torque is reversed and the volume of the introduction target chamber is to be reduced, the hydraulic fluid introduced into the introduction target chamber is pushed out to the return passage before the reverse, but flows to the discharge port side in the return passage. Since the reflux is regulated by the reflux check valve, the return of the changed rotational phase is suppressed.

  In such a phase change mode recirculation operation, since the drain port connected to the discharge port via the drain passage is open to the atmosphere, there is a concern about the intake of air in the introduction target chamber in which negative pressure is generated due to volume expansion. . However, independent of the reflux passage through which negative pressure propagates from the introduction target chamber, the discharge port where the drain passage of atmospheric pressure opens is in a positive pressure state due to the inflow of hydraulic fluid pushed out from the discharge target chamber. A situation in which air is sucked from the drain passage into the return passage through the discharge port can be suppressed. In addition, in the phase change mode, even when the spool moves in the increasing direction and both the reflux area and the drain area increase, the drain area even when the spool moves in the decreasing direction and both the reflux area and the drain area decrease. Is maintained smaller than the reflux area. As a result, since it becomes difficult for air to flow between the drain passage and the discharge port at an arbitrary movement position of the spool in the phase change mode, it is possible to suppress a situation where air is sucked into the return passage from the drain passage through the discharge port. The effect can be enhanced. According to the above, it is possible to avoid the rampage of the vane rotor due to air being sucked into the introduction target chamber through the reflux passage, and to improve the valve timing adjustment responsiveness.

  According to the second aspect of the present invention, the discharge port forms a groove extending in the circumferential direction along the inner peripheral surface of the sleeve, and the opening of the reflux passage and the opening of the drain passage are the outer peripheral surface of the spool. Are provided at locations shifted in the circumferential direction and open toward the groove in the phase change mode.

  In such a phase change mode of the invention, the opening portion of the reflux passage provided on the outer peripheral surface of the spool opens toward the groove portion extending along the inner peripheral surface of the sleeve of the discharge port. To connect the introduction port. At the same time, in the phase change mode, the opening portion of the drain passage provided at a position shifted in the circumferential direction from the opening portion of the reflux passage on the outer peripheral surface of the spool opens toward the forming groove portion of the discharge port extending in the circumferential direction. Thus, the drain port can be connected to the discharge port independently of the introduction port. In such a phase change mode, the drain area between the opening of the drain passage and the formation groove is smaller than the return area between the opening of the return passage and the formation groove of the discharge port regardless of the movement of the spool. By being maintained, inhalation of air from the drain passage to the reflux passage can be suppressed. According to this, it is possible to avoid the rampage of the vane rotor due to air being sucked into the introduction target chamber by switching from the above-described supply pressure operation to the reflux operation, and to improve the valve timing adjustment responsiveness. Become.

  According to the third aspect of the present invention, the spool connects the discharge port and the drain port by opening the drain passage toward the discharge port in the connection mode in the phase change mode. By closing the drain passage with respect to the discharge port in the shut-off mode, the discharge port and the drain port are shut off, and in both the connection mode and the shut-off mode, the return passage is opened toward the discharge port. And connection between the introduction ports.

  In the cutoff mode among the phase change modes of the invention as described above, the discharge port and the introduction port are connected by the opening of the reflux passage toward the discharge port, while the drain port and the drain port are blocked by the blockage of the drain passage with respect to the discharge port. Is cut off. As a result, in the shut-off mode, only the latter of the supply pressure operation and the recirculation operation occurs without causing the intake of air from the drain passage to the recirculation passage through the discharge port, thereby improving the valve timing adjustment responsiveness. Is possible.

  Further, in the connection mode among the phase change modes, not only the discharge port and the introduction port are connected by the opening of the return passage toward the discharge port, but also the discharge port and the drain port are opened by the opening of the drain passage toward the discharge port. Are connected. As a result, in the connection mode, one of the supply pressure operation and the recirculation operation occurs depending on the supply pressure of the hydraulic fluid. In particular, in the recirculation operation, air is sucked from the drain passage to the recirculation passage through the discharge port. Can be suppressed. Therefore, it is possible to improve the valve timing adjustment responsiveness by avoiding the vane rotor rampage resulting from the intake of air into the introduction target chamber by switching from the cutoff mode to the connection mode.

  According to the fourth aspect of the present invention, the spool moves in the increasing direction when switching from the shut-off mode to the connection mode, thereby opening the reflux passage toward the discharge port prior to the drain passage.

  In such an invention, the spool is moved in the increasing direction from the shut-off mode in which the drain port is shut off with respect to the discharge port, so that the drain passage also becomes the discharge port following the reflux passage that opens first toward the discharge port. It is possible to realize the switching to the connection mode by opening the screen. Therefore, it is possible to avoid the rampage of the vane rotor due to the intake of air by switching to the connection mode, and improve the adjustment response of the valve timing.

  According to the invention described in claim 5, the discharge port forms a groove extending in the circumferential direction along the inner peripheral surface of the sleeve, and the opening of the reflux passage and the opening of the drain passage are the outer peripheral surface of the spool. In the connection mode, opening toward the groove portion in the connection mode, the opening portion of the return passage on the outer peripheral surface of the spool, the region overlapping the opening portion of the drain passage along the axial direction, It is provided across the region shifted from the overlapping region in the increasing direction.

  In such a connection mode of the invention, the opening portion of the return passage provided on the outer peripheral surface of the spool opens toward the groove portion extending along the inner peripheral surface of the sleeve of the discharge port. An introduction port can be connected. At the same time, in the connection mode, the opening of the drain passage provided at a location shifted in the circumferential direction from the opening of the reflux passage on the outer peripheral surface of the spool opens toward the formation groove portion of the discharge port extending in the circumferential direction. The drain port can be connected to the discharge port independently of the introduction port. With such a connection mode, in the connection mode in which the opening portion of the return passage overlaps the opening portion of the drain passage along the axial direction on the outer peripheral surface of the spool, in the cutoff mode, the opening portion shifts in an increasing direction from the overlapping region. Only the opening of the reflux passage spanning the region can open toward the groove. According to the above, by moving the spool from the shut-off mode in the increasing direction, following the opening of the reflux passage that opens first toward the discharge port, the opening of the drain passage is also opened toward the discharge port, Switching to connection mode can be realized. Therefore, it is possible to avoid the vane rotor rampage caused by the intake of air by switching to the connection mode, and to improve the valve timing adjustment response.

It is a schematic diagram which shows the basic composition of the valve timing adjustment apparatus by one Embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is a characteristic view for demonstrating the fluctuation | variation torque which acts on the valve timing adjustment apparatus by one Embodiment of this invention. It is a characteristic view for demonstrating disorder of the alternating waveform of the fluctuation | variation torque shown in FIG. It is a schematic diagram which shows the specific structure of the control part of the valve timing adjustment apparatus by one Embodiment of this invention. It is a schematic diagram which shows the operation state different from FIG. It is a schematic diagram which shows the operation state different from FIG. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a schematic diagram which shows the operation state different from FIGS. It is a perspective view which shows the spool of the control valve of FIG. It is a front view which shows the spool of the control valve of FIG. It is a figure which shows the spool of the control valve of FIG. 5, Comprising: (a) is the sectional view on the aa line of FIG. 17, (b) is the sectional view on the bb line of FIG. It is a characteristic view for demonstrating the control valve of the valve timing adjustment apparatus by one Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example in which a valve timing adjusting device 1 according to an embodiment of the present invention is applied to an internal combustion engine of a vehicle. The valve timing adjustment device 1 is a fluid drive type that uses hydraulic oil as “hydraulic fluid” and adjusts the valve timing of the intake valve as “valve”.

(Basic configuration)
Hereinafter, a basic configuration of the valve timing adjusting device 1 will be described. As shown in FIGS. 1 and 2, the valve timing adjusting device 1 includes a drive unit 10 installed in a transmission system for transmitting engine torque output from a crankshaft (not shown) to the camshaft 2 in an internal combustion engine, and the drive unit. And a control unit 30 that controls the entry and exit of hydraulic oil for driving 10.

  The drive unit 10 includes a housing 11 and a vane rotor 15. The housing 11 is formed by fastening a front plate 13 and a rear plate 14 to both axial ends of the shoe casing 12. The shoe casing 12 includes a cylindrical casing body 12a, a plurality of shoes 12b, 12c, and 12d that are partition portions, and a sprocket portion 12e. Each shoe 12b, 12c, 12d protrudes inward in the radial direction from a location spaced apart by a predetermined interval in the rotation direction in the casing body 12a. A storage chamber 50 is formed between the shoes 12b, 12c, and 12d adjacent in the rotation direction. The sprocket portion 12e is connected to the crankshaft via a timing chain (not shown). With this connection, while the internal combustion engine is rotating, engine torque is transmitted from the crankshaft to the sprocket portion 12e, so that the housing 11 rotates in a fixed direction (clockwise in FIG. 1) in conjunction with the crankshaft.

  The vane rotor 15 is coaxially disposed in the housing 11. The vane rotor 15 includes a cylindrical rotating shaft 15a and a plurality of vanes 15b, 15c, and 15d. The rotating shaft 15 a is fixed coaxially with the cam shaft 2. With this fixing, the vane rotor 15 can rotate in a fixed direction (clockwise in FIG. 1) in conjunction with the camshaft 2 and can rotate relative to the housing 11. Each of the vanes 15b, 15c, and 15d protrudes radially outward from a position spaced apart by a predetermined interval in the rotation direction on the rotation shaft 15a, and is accommodated in the corresponding accommodation chamber 50.

  As shown in FIG. 1, each vane 15 b, 15 c, 15 d divides the corresponding accommodating chamber 50 in the rotational direction, thereby allowing the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 to be in the housing 11. It is divided into. Specifically, an advance chamber 52 is formed between the shoe 12b and the vane 15b, an advance chamber 53 is formed between the shoe 12c and the vane 15c, and an advance angle is formed between the shoe 12d and the vane 15d. A chamber 54 is formed. Further, a retard chamber 56 is formed between the shoe 12c and the vane 15b, a retard chamber 57 is formed between the shoe 12d and the vane 15c, and a retard chamber 58 is formed between the shoe 12b and the vane 15d. Is formed. The vane 15b holds a lock member 16 that locks the rotation phase of the vane rotor 15 with respect to the housing 11 by fitting into the lock hole 14a of the rear plate 14 when the internal combustion engine is stopped. The lock member 16 is separated from the lock hole 14a when the internal combustion engine is started, thereby allowing a change in rotational phase during steady operation of the internal combustion engine.

  With this configuration, in the drive unit 10, the rotational phase changes due to the hydraulic oil entering and exiting the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 with steady operation of the internal combustion engine. The valve timing according to the phase is realized. Specifically, the volume of the advance chambers 52, 53, and 54 is increased by introducing the hydraulic oil, and the volume of the retard chambers 56, 57, and 58 is reduced by discharging the hydraulic oil, so that the rotation phase is advanced. The valve timing is advanced accordingly. On the other hand, the retarding chambers 56, 57, and 58 are expanded in volume by introducing the hydraulic oil, and the advanced chambers 52, 53, and 54 are reduced in volume by discharging the hydraulic oil, so that the rotational phase is changed to the retarded side. Accordingly, the valve timing is retarded accordingly.

  The control unit 30 includes the passages 60, 61, 62, 65, the control valve 70, and the control circuit 90 with respect to the drive unit 10 described above. The advance angle control passage 60 communicates with each advance angle chamber 52, 53, 54 of the drive unit 10. The retard control passage 61 communicates with each retard chamber 56, 57, 58 of the drive unit 10. The supply passage 62 communicates with the discharge port of the pump 4 as a “supply source”, so that hydraulic oil sucked from the drain pan 5 to the suction port of the pump 4 is discharged and supplied. Here, the pump 4 is a mechanical pump that is driven by the rotation of the crankshaft of the internal combustion engine, and hydraulic oil is continuously supplied from the pump 4 to the supply passage 62 during the rotation. The drain collecting passage 65 is opened to the atmosphere together with the drain pan 5 as a drain collecting portion, and the hydraulic oil can be discharged to the drain pan 5.

  The control valve 70 is an electromagnetically driven spool valve that reciprocally drives the spool 73 as a valve member by using a driving force generated by energizing the solenoid 71 and a restoring force generated by the return spring 72. The control valve 70 has an advance angle control port 80, a retard angle control port 81, a supply port 82, an advance angle drain port 85, and a retard angle drain port 86. Here, the advance angle control port 80 and the retard angle control port 81 communicate with the advance angle control path 60 and the retard angle control path 61, respectively, and the supply port 82 communicates with the supply path 62. Further, both the advance drain port 85 and the retard drain port 86 are open to the atmosphere by communicating with the drain collection passage 65. The control valve 70 switches the connection state between these ports 80, 81, 82, 85, 86 by changing the moving position of the spool 73 in accordance with the energization of the solenoid 71. For example, the control valve 70 may be disposed inside at least one of the vane rotor 15 and the cam shaft 2 of the drive unit 10 or may be disposed outside the drive unit 10. The passages 60, 61, 62, 65 are provided inside or outside the drive unit 10 according to the arrangement form.

  The control circuit 90 is an electronic circuit mainly composed of a microcomputer, for example, and is electrically connected to the solenoid 71 of the control valve 70 and various electrical components (not shown) of the internal combustion engine. The control circuit 90 controls the rotation of the internal combustion engine including energization to the solenoid 71 in accordance with a computer program stored in the internal memory.

(Feature)
Hereinafter, features of the valve timing adjusting device 1 will be described in detail.

(Variable torque)
First, as a characteristic of the valve timing adjusting device 1, the fluctuation torque acting on the device 1 will be described.

  During the rotation of the internal combustion engine, fluctuating torque generated due to a spring reaction force or the like from an intake valve driven to open and close by the cam shaft 2 acts on the vane rotor 15 of the drive unit 10 through the cam shaft 2. Here, as shown in FIG. 3, the fluctuating torque alternates between a negative torque acting on the advance side with respect to the housing 11 and a positive torque acting on the retard side with respect to the housing 11. The fluctuating torque may be such that, for example, the positive torque peak torque T + becomes larger than the negative torque peak torque T-, so that the average torque is biased to the positive torque side, or the positive torque peak torque T + is The average torque may be substantially zero by being substantially equal to the negative torque peak torque T−.

  Here, the fluctuating torque shows a tendency that the alternating waveform is disturbed as shown in FIG. 4 when the rotational speed of the internal combustion engine increases. As a result of such disturbance, even if the rotation angle of the camshaft 2 originally generates a positive torque, a negative torque is generated. Conversely, the rotation angle of the camshaft 2 that originally generates a negative torque However, a positive torque may be generated.

(Control part)
Next, as a feature of the valve timing adjusting device 1, a specific configuration of the control unit 30 will be described.

  As shown in FIG. 5, in the control unit 30, the control valve 70 accommodates the spool 73 in the sleeve 100. The sleeve 100 is formed of a metal in a cylindrical shape, and an advance drain port 85, a retard control port 81, a supply port 82, an advance control port 80, and a retard drain port 86 are arranged in this order in the axial direction. Yes. Here, in the present embodiment, the advance angle control port 80 and the retard angle control port 81 are formed with groove portions 80 a and 81 a in portions that open to the inner peripheral surface 100 a of the sleeve 100. These groove portions 80a and 81a are formed in an annular groove shape that continuously extends in the circumferential direction along the inner peripheral surface 100a. However, as long as they can communicate with the passages 110 and 112 or the passages 111 and 113 described later in detail. Then, it may be formed in an arc groove shape extending in the circumferential direction with a length of less than one round.

  A spool 73 formed of a metal in a cylindrical rod shape is coaxially arranged in the sleeve 100 and can reciprocate in the axial direction. A drive shaft 71 a of a solenoid 71 is linked to one end 73 a of the spool 73, and a return spring 72 is linked to the other end 73 b of the spool 73. The solenoid 71 presses the spool 73 to the return spring 72 side by the driving force of the drive shaft 71 a according to the energization from the control circuit 90, and the return spring 72 has a restoring force corresponding to the compression deformation with the sleeve 100. The spool 73 is pressed toward the solenoid 71 by the occurrence of the above. Therefore, in the control valve 70, the movement position of the spool 73 (hereinafter simply referred to as “spool movement position”) according to the balance between the driving force that the solenoid 71 applies to the driving shaft 71 a and the restoring force that the return spring 72 generates. Will be determined.

  In the spool 73, an advance recirculation passage 110, a retard recirculation passage 111, an advance drain passage 112, and a retard drain passage 113 are formed. The one end portions 110a and 111a of the advance recirculation passage 110 and the retard recirculation passage 111 penetrating the spool 73 in a hole shape are integrally open to the outer peripheral surface 73c of the spool 73. The other end portions 110 b and 111 b of the advance recirculation passage 110 and the retard recirculation passage 111 open to the outer peripheral surface 73 c of the spool 73 at locations spaced apart from each other in the axial direction of the spool 73.

  As shown in FIGS. 5 and 16 to 18, the advance drain passage 112 is formed in a groove shape that is entirely open from the one end 112 a to the other end 112 b in the outer peripheral surface 73 c of the spool 73. Here, the advance drain passage 112 is an opening that extends in the axial direction of the spool 73 at a location that is shifted in the circumferential direction from the opening 110 c on the end 110 b side of the advance return passage 110 of the outer peripheral surface 73 c of the spool 73. 112c is formed. As a result, the opening 110c of the advance recirculation passage 110 is shifted in the direction Da from the region Sa1 overlapping the opening 112c on the end 112b side of the advance drain passage 112 along the axial direction as shown in FIG. Is disposed across the area Sa2. The direction Da with respect to the spool 73 is a moving direction toward the return spring 72 in the axial direction.

  The retard drain passage 113 is provided at a position on the opposite side of the advance reflux passage 110 across the retard return passage 111 in the axial direction in the spool 73. The retard drain passage 113 is formed in a hole shape in which a part including the one end 113 a passes through the spool 73. Further, as shown in FIGS. 5 and 15 to 17, the retarded drain passage 113 is formed in a groove shape in which the remaining portion including the other end portion 113 b opens to the outer peripheral surface 73 c of the spool 73. Here, the remaining portion of the retarded drain passage 113 extends in the axial direction of the spool 73 at a location that is shifted in the circumferential direction from the opening 111 c on the end 111 b side of the retarded reflux passage 111 on the outer peripheral surface 73 c of the spool 73. An opening 113c that extends is formed. As a result, the opening 111c of the retarded recirculation passage 111 is shifted in the direction Dr from the region Sr1 that overlaps the opening 113c on the end 113b side of the retarding drain passage 113 along the axial direction as shown in FIG. Is disposed across the region Sr2. The direction Dr with respect to the spool 73 is a direction opposite to the direction Da in the axial direction, that is, a moving direction toward the solenoid 71 side.

  With this configuration, in the first advance angle mode A1 spool movement position shown in FIGS. 1, 5, and 6, one end portion 110 a of the advance angle return passage 110 communicates with the advance angle control port 80 and the supply port 82. The other end portion 110 b communicates with the retard angle control port 81. Here, the advance angle recirculation passage 110 of the present embodiment opens the opening portion 110c on the other end portion 110b side toward the groove portion 81a of the retard angle control port 81 to be communicated, whereby the retardation angle control port 81 is concerned. And the advance angle control port 80 are connected. Further, at the spool movement position in the first advance angle mode A1, one end portion 111a of the retarded angle return passage 111 communicates with the advance angle control port 80 and the supply port 82, and the other end portion 111b of the passage 111 is blocked by the sleeve 100. Is done.

  Further, at the spool movement position in the first advance angle mode A1, one end 113a of the retard drain passage 113 communicates with the retard drain port 86, and the other end 113b of the retard drain passage 113 is closed by the sleeve 100. . Furthermore, at the spool movement position in the first advance angle mode A1, at least one end 112a of the advance drain passage 112 communicates with the advance drain port 85, and the other end 112b of the passage 112 is retarded by the sleeve 100. The port 81 is blocked and the connection between the ports 85 and 81 is blocked.

  In the second advance angle mode A2 spool movement position shown in FIGS. 1, 7 to 9, one end portion 110 a of the advance angle recirculation passage 110 communicates with the advance angle control port 80 and the supply port 82, and the other end portion of the passage 110. 110 b communicates with the retardation control port 81. Here, the advance angle recirculation passage 110 of the present embodiment opens the opening portion 110c on the other end portion 110b side toward the groove portion 81a of the retard angle control port 81 to be communicated, whereby the retardation angle control port 81 is concerned. And the advance angle control port 80 are connected. Further, at the spool movement position in the second advance angle mode A2, one end portion 111a of the retarded angle return passage 111 communicates with the advance angle control port 80 and the supply port 82, and the other end portion 111b of the passage 111 is blocked by the sleeve 100. Is done.

  Further, at the spool movement position in the second advance angle mode A2, one end portion 113a of the retarded drain passage 113 communicates with the retarded drain port 86, and the other end portion 113b of the passage 113 is closed by the sleeve 100. Furthermore, at the spool movement position in the second advance angle mode A2, at least one end 112a of the advance drain passage 112 communicates with the advance drain port 85, and the other end 112b of the passage 112 communicates with the retard control port 81. The ports 85 and 81 are connected in communication. Here, the advance drain passage 112 of this embodiment opens the opening 112c on the other end 112b side independently of the advance return passage 110 toward the groove portion 81a of the retard control port 81 to be communicated. By doing so, the retard control port 81 and the advance drain port 85 are connected.

  By the way, when switching from the first advance angle mode A1 to the second advance angle mode A2, the spool 73 moves in the direction Da. Due to the movement in the direction Da, the opening 110c in the region Sa2 (see FIG. 17) of the advance recirculation passage 110 is delayed before the opening 112c in the region Sa1 (see FIG. 17) of the advance drain passage 112. The angle control port 81 opens toward the groove 81a. That is, by the movement in the direction Da, the opening 112c of the advance drain passage 112 is also formed in the groove 81a following the opening 110c of the advance recirculation passage 110 that opens first toward the groove 81a of the retard control port 81. It will open toward. Further, after switching to the second advance angle mode A2, between the openings 110c of the areas Sa1 and Sa2 of the advance angle recirculation passage 110 and the groove 81a of the retard angle control port 81 and the area Sa1 of the advance angle drain path 112. Between the opening 112c and the groove 81a, the flow areas Fac and Fad are reduced, respectively.

  Here, as shown in FIG. 19, in the second advance angle mode A2, the distribution areas Fac and Fad both increase as the spool 73 moves in the direction Da, while the distribution occurs as the spool 73 moves in the opposite direction Dr. Both areas Fac and Fad decrease. At the same time, in the second advance angle mode A2, the movement in any direction is ensured between the opening 112c and the groove 81a rather than the flow area Fac ensured between the opening 110c and the groove 81a. The distribution area Fad is kept small.

  In this embodiment, in the second advance angle mode A2 shown in FIGS. 7 to 9, the flow amount of the hydraulic oil flowing through the advance return path 110 from the retard control port 81 to the advance control port 80 side is Control is possible according to the flow area Fac between the advance and return passage 110 and the retard control port 81. On the other hand, in the second advance angle mode A <b> 2, the flow amount of the hydraulic fluid flowing through the advance drain passage 112 from the retard control port 81 to the advance drain port 85 side is between the advance drain passage 112 and the retard control port 81. It becomes controllable according to the distribution area Fad.

  In the spool movement position of the first retard mode R1 shown in FIGS. 1, 10, and 11, one end 111a of the retard return path 111 communicates with the retard control port 81 and the supply port 82, and the other end of the path 111. 111 b communicates with the advance angle control port 80. Here, the retarded angle recirculation passage 111 of the present embodiment opens the opening portion 111c on the other end 111b side toward the groove portion 80a of the advance angle control port 80 to be communicated, thereby retarding the port 80. Connect to the control port 81. Further, at the spool movement position in the first retard angle mode R1, one end portion 110a of the advance angle recirculation passage 110 communicates with the retard angle control port 81 and the supply port 82, and the other end portion 110b of the passage 110 is closed by the sleeve 100. Is done.

  Further, at the spool movement position in the first retard angle mode R1, at least one end 112a of the advance drain passage 112 communicates with the advance drain port 85, and the other end 112b of the passage 112 is closed by the sleeve 100. Furthermore, at the spool movement position in the first retard angle mode R1, one end 113a of the retard drain passage 113 communicates with the retard drain port 86, and the other end 113b of the passage 113 is advanced by the sleeve 100. 80 is blocked, and the ports 86 and 80 are blocked.

  At the spool movement position of the second retardation mode R2 shown in FIGS. 1, 12 to 14, one end portion 111 a of the retardation return passage 111 communicates with the retardation control port 81 and the supply port 82 and the other end of the passage 111. The unit 111 b communicates with the advance angle control port 80. Here, the retarded angle recirculation passage 111 of the present embodiment opens the opening 111c on the other end 111b side toward the groove 80a of the advance angle control port 80 to be communicated, so that the advance angle control port 80 is concerned. And the retard control port 81 are connected. Further, at the spool movement position in the second retardation mode R2, one end portion 110a of the advance recirculation passage 110 communicates with the retardation control port 81 and the supply port 82, and the other end portion 110b of the passage 110 is blocked by the sleeve 100. Is done.

  Further, at the spool movement position in the second retard angle mode R2, at least one end 112a of the advance drain passage 112 communicates with the advance drain port 85, and the other end 112b of the passage 112 is closed by the sleeve 100. Furthermore, at the spool movement position in the second retard angle mode R2, one end 113a of the retard drain passage 113 communicates with the retard drain port 86, and the other end 113b of the passage 113 communicates with the advance control port 80. To do. Here, the retarded drain passage 113 of the present embodiment opens the opening 113c on the other end 113b side independently of the retarded reflux passage 111 toward the groove 80a of the advance control port 80 to be communicated. By doing so, the advance angle control port 80 and the retard angle drain port 86 are connected.

  By the way, when switching from the first retardation mode R1 to the second retardation mode R2, the spool 73 moves in the direction Dr. Due to the movement in the direction Dr, the opening 111c in the region Sr2 (see FIG. 17) of the retarded recirculation passage 111 is advanced ahead of the opening 113c in the region Sr1 (see FIG. 17) of the retarding drain passage 113. The control port 80 opens toward the groove 80a. That is, by the movement in the direction Dr, the opening 113c of the retarded drain passage 113 is also formed in the groove 80a following the opening 111c of the retarding reflux passage 111 that opens first toward the groove 80a of the advance control port 80. It will open toward. In addition, after switching to the second retard angle mode R2, between the opening 111c of the regions Sr1 and Sr2 of the retard return passage 111 and the groove portion 80a of the advance control port 80 and the region Sr1 of the retard drain passage 113. Between the opening 113c and the groove 80a, the flow areas Frc and Frd are reduced, respectively.

  Here, in the second retardation mode R2, as shown in FIG. 19, the flow areas Frc and Frd both increase as the spool 73 moves in the direction Dr, while the flow occurs as the spool 73 moves in the opposite direction Da. Both areas Frc and Frd decrease. At the same time, in the second retardation angle mode R2, the movement in any direction is secured between the opening 113c and the groove 80a rather than the flow area Frc secured between the opening 111c and the groove 80a. Thus, a small relationship is maintained in the distribution area Frd.

  In this embodiment, in the second retardation mode R2 shown in FIGS. 12 to 14, the flow amount of hydraulic fluid that circulates in the retardation return passage 111 from the advance control port 80 to the retard control port 81 side is Control is possible in accordance with the flow area Frc between the retarded return passage 111 and the advance control port 80. On the other hand, in the second retard angle mode R2, the flow rate of the hydraulic fluid that flows through the retard drain passage 113 from the advance control port 80 to the retard drain port 86 side is between the retard drain passage 113 and the advance control port 80. It becomes controllable according to the distribution area Frd.

  In the holding mode H spool movement position shown in FIGS. 1 and 15, both the advance angle control port 80 and the retard angle control port 81 are closed by the spool 73. Further, at the spool movement position in the holding mode H, the one end portions 110a and 111a of the advance recirculation passage 110 and the retard recirculation passage 111 communicate with the supply port 82, and the advance recirculation passage 110 and the retard recirculation passage 111 The other end portions 110 b and 111 b are closed by the sleeve 100. Further, at the spool movement position in the holding mode H, at least one end 112 a of the advance drain passage 112 communicates with the advance drain port 85, and the other end 112 b of the passage 112 is closed by the sleeve 100. Further, at the spool movement position in the holding mode H, one end portion 113 a of the retarded drain passage 113 communicates with the retarded drain port 86, and the other end portion 113 b of the passage 113 is closed by the sleeve 100.

  Now, an advance recirculation check valve 120 and a retard recirculation check valve 121 are disposed in the advance recirculation passage 110 and the retard recirculation passage 111 of the spool 73, respectively. As shown in FIG. 5, each of the reflux check valves 120 and 121 is formed by combining individual valve seats 122 and 123 and valve members 124 and 125 and a common elastic member 126.

  The advance valve seat 122 is formed by a conical surface whose diameter is reduced toward the end 110b side of the inner wall surface of the advance return passage 110. The advance valve member 124 formed of a metal in a bottomed cylindrical shape is disposed coaxially with the valve seat 122 on the end 110a side of the advance valve seat 122 in the advance reflux passage 110, and is axially disposed. It can move back and forth. As a result, the bottom of the advance valve member 124 is seated on the advance valve seat 122 by moving toward the end 110b, and is separated from the advance valve seat 122 by moving toward the end 110a.

  The retard valve seat 123 is formed by a conical surface that is reduced in diameter toward the end 111 b side of the inner wall surface of the retard return passage 111. The retard valve member 125 formed of a metal in a bottomed cylindrical shape is disposed coaxially with the valve seat 123 on the end 111a side of the retard valve seat 123 in the retard return passage 111, and is axially disposed. It can move back and forth. Accordingly, the bottom portion of the retard valve member 125 is seated on the retard valve seat 123 by moving to the end portion 111b side, and is separated from the retard valve seat 123 by moving to the end portion 111a side.

  An elastic member 126 made of a metal coil spring is coaxially interposed between the advance valve member 124 and the retard valve member 125. As a result, the elastic member 126 generates a restoring force corresponding to the compression deformation between the advance valve member 124 and the retard valve member 125, thereby causing the advance valve member 124 and the retard valve member 125 to advance. It pushes to the angle valve seat 122 side and the retard valve seat 123 side.

  With this configuration, the advance valve member 124 resists the restoring force of the elastic member 126 because the end 110b side of the advance recirculation passage 110 has a higher pressure across the advance valve seat 122 than the end 110a side. When the valve is moved away from the advance valve seat 122, the advance return check valve 120 is opened. Thereby, in the advance angle recirculation passage 110 of modes A1 and A2, the recirculation of the hydraulic oil flowing from the retard angle control port 81 to the advance angle control port 80 side is allowed (see FIGS. 5 and 8). On the other hand, the advancement valve member 124 that receives the restoring force of the elastic member 126 becomes higher than the end 110b side with respect to the advancement valve seat 122 in the advancement return passage 110, so that the advancement valve member 124 that receives the restoring force of the elastic member 126 becomes the advancement valve. When sitting on the seat 122, the advance return check valve 120 is closed. Thereby, in the advance angle recirculation passage 110 of modes A1 and A2, the recirculation of the hydraulic oil flowing from the advance angle control port 80 to the retard angle control port 81 side is regulated (see FIGS. 6, 7, and 9).

  Further, the retarding valve member 125 is retarded against the restoring force of the elastic member 126 because the end 111b side is higher than the end 111a side of the retarding valve passage 123 in the retarding return passage 111. When the angular valve seat 123 is separated, the retarded reflux check valve 121 is opened. As a result, in the retarded recirculation passage 111 of modes R1 and R2, the recirculation of the hydraulic oil flowing from the advance angle control port 80 to the retard angle control port 81 side is allowed (see FIGS. 10 and 13). On the other hand, the retarding valve member 125 that receives the restoring force of the elastic member 126 becomes the retarding valve because the end 111a side becomes higher than the end 111b side across the retarding valve seat 123 in the retarding return passage 111. When seated on the seat 123, the retarded reflux check valve 121 is closed. As a result, the recirculation of the hydraulic oil flowing from the retard control port 81 to the advance control port 80 side is regulated in the retard return passage 111 of the modes R1 and R2 (see FIGS. 11, 12, and 14).

  In addition to the above, a supply flow check valve 130 is disposed in the supply passage 62 of the control unit 30 as shown in FIGS. The supply flow check valve 130 is opened when the pump 4 side is at a higher pressure than the supply port 82 side across the supply passage 62. Thereby, the supply flow from the pump 4 to the supply port 82 side is allowed in the supply passages 62 of modes A2 and R2 (see FIGS. 7 and 12). On the other hand, the supply flow check valve 130 is in a closed state when the supply port 82 side has a higher pressure than the pump 4 side across the supply passage 62. Thereby, in the supply passage 62 of modes A1 and R1, the backflow from the supply port 82 side to the pump 4 is regulated (see FIGS. 5, 6, 8 to 11, 13, and 14).

(Operation)
Next, the operation of the device 1 will be described as a feature of the valve timing adjusting device 1. When the internal combustion engine is continuously supplied with hydraulic oil from the pump 4 (hereinafter simply referred to as “steady operation”), the control circuit 90 supplies the solenoid 71 with a valve timing suitable for the operation state. Is selected from among the spool movement positions of modes A1, A2, R1, R2, and H. As a result, the entry and exit of the hydraulic oil to and from the advance chambers 52, 53, and 54 and the retard chambers 56, 57, and 58 are controlled according to the selected spool movement position. Therefore, in the following, the operation of each mode A1, A2, R1, R2, H during steady operation will be described individually. Immediately after the start of steady operation in the internal combustion engine, all of the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are filled with the hydraulic fluid supplied from the pump 4. It has become.

(1) First advance mode A1
When operating conditions such as the rotational speed of the internal combustion engine being smaller than a predetermined value and the actual phase being on the retard side with respect to the target phase relative to the target phase during steady operation, the first advance angle mode A1 shown in FIGS. A spool movement position is selected. In this spool movement position, the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are connected via the advance return passage 110 between the ports 80, 81, and the retard return passage 111. Of these, the end portion 111 b on the opposite side of the advance / return passage 110 is closed by the sleeve 100. Further, in the advance recirculation passage 110, an end 110a on the advance control port 80 side is connected to the supply passage 62, and an end 110b on the retard control port 81 side is connected to the advance drain passage 112 and the drain recovery passage 65. Separated from.

  Under such a connection form, as shown in FIG. 5, when a negative torque of the variable torque acts on the vane rotor 15 to cause a rotational phase change that reduces the retarding chambers 56, 57, 58, these retarding chambers 56, 57. , 58 are pushed out through the retard control port 81 into the advance recirculation passage 110. At this time, the advance angle return passage 110 connected to the advance chambers 52, 53, and 54 whose volume is expanded by the action of negative torque via the advance control port 80 and separated from the advance drain passage 112, Reflux flowing to the advance angle control port 80 side is allowed by the advance angle check valve 120. On the other hand, in the retarded-angle reflux passage 111 and the supply passage 62 connected to the advanced-angle reflux passage 110, the retarded-back reflux check valve 121 and the supply flow check valve 130 are closed. Accordingly, in the advance chambers 52, 53, and 54 in which negative pressure is generated due to the volume expansion, the advance fluid return passage 110 is discharged in an amount corresponding to the flow area Fac of the discharged hydraulic oil from the retard chambers 56, 57, and 58. Inhaled through. On the other hand, air is not sucked into the advance chambers 52, 53, 54 from the advance drain passage 112 opened to the atmosphere through the advance return passage 110. According to these, the valve timing can be advanced by changing the rotational phase to the advance side.

  In addition, as shown in FIG. 6, when the direction of the variable torque is reversed and the positive torque acts on the vane rotor 15, the advance chambers 52, 53, and 54 try to reduce the volume. The hydraulic oil introduced into 52, 53, and 54 is pushed out to the advance and return passage 110. At this time, the recirculation that flows to the retard control port 81 side in the advance recirculation passage 110 is regulated by the advance recirculation check valve 120. At the same time, the retarded reflux check valve 121 and the feed flow check valve 130 are closed in the retarded reflux passage 111 and the supply passage 62, respectively. According to the above, since it is possible to suppress a situation in which the rotational phase changed to the advance side before reversing the variable torque returns to the retard side, it is possible to improve the advance response of the valve timing.

(2) Second advance angle mode A2
When operating conditions such as the rotational speed of the internal combustion engine being larger than a predetermined value and the actual phase being on the retard side with respect to the target phase relative to the target phase during steady operation, the second advance angle mode A2 shown in FIGS. A spool movement position is selected. In this spool movement position, the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are connected via the advance return passage 110 between the ports 80, 81, and the retard return passage 111. Of these, the end portion 111 b on the opposite side of the advance / return passage 110 is closed by the sleeve 100. Further, in the advance recirculation passage 110, an end 110a on the advance control port 80 side is connected to the supply passage 62, and an end 110b on the retard control port 81 side is an advance drain passage between the ports 81 and 85. It is connected to the drain recovery passage 65 through 112.

  Under such a connection configuration, the supply flow check valve 130 allows the supply flow to the supply port 82 side in the supply passage 62, so that the hydraulic oil supplied from the pump 4 is supplied to the supply port as shown in FIG. It circulates from 82 to the advance angle control port 80 side. At this time, when the supply pressure of the hydraulic oil from the pump 4 becomes a set pressure (for example, 200 kPa) or more, the advance angle control port 80 retards the advance angle recirculation passage 110 into which the hydraulic oil flows. The reflux that flows to the control port 81 side is regulated by the advance reflux check valve 120. At the same time, the retarded-reflux check valve 121 is closed in the retarded-reflux passage 111 connected to the advance-reflux passage 110. As a result, the hydraulic oil is introduced into the advance chambers 52, 53, 54 through the advance control port 80, and the hydraulic oil is introduced into the retard chambers 56, 57 through the advance drain passage 112 connected to the retard control port 81. , 58 are sequentially discharged to the advance drain port 85 and the drain recovery passage 65. According to the above supply pressure operation, under the operating conditions in which the fluctuation response torque is disturbed as the internal combustion engine rotates at a high speed (see FIG. 4), the operation responsiveness of the advance recirculation check valve 120 becomes low. The hydraulic fluid supplied from the pump 4 can be introduced into the advance chambers 52, 53, 54 instead of the hydraulic fluid discharged from the corner chambers 56, 57, 58. Therefore, the valve timing can be advanced by changing the rotational phase to the advance side, regardless of the fluctuation of the fluctuation torque.

  However, when the supply pressure of the hydraulic oil becomes less than the set pressure due to the temperature rise, the operation of the recirculation check valves 120 and 121 according to the fluctuation torque corresponds to the recirculation operation of the above (1). As a result, the hydraulic oil discharged from the retard chambers 56, 57, 58 is introduced into the advance chambers 52, 53, 54. According to this, even if the supply pressure of the hydraulic oil from the pump 4 decreases, it is possible to continue the advance timing of the valve timing.

  Here, in the recirculation operation in the second advance angle mode A2, since the advance drain port 85 connected to the retard control port 81 via the advance drain passage 112 is opened to the atmosphere, the negative torque action as shown in FIG. In the advance chambers 52, 53, and 54 in which negative pressure is generated due to the above, there is a concern that air is sucked. However, independently of the advance recirculation passage 110 through which the negative pressure propagates from the advance chambers 52, 53, 54, the retard control port 81 in which the atmospheric pressure advance drain passage 112 is opened has the retard chamber 56, A positive pressure state is obtained by the inflow of the hydraulic oil pushed out from 57 and 58. As a result, a situation in which air is sucked from the advance drain passage 112 through the retard control port 81 into the advance return passage 110 can be suppressed. In addition, the flow area Fad between the advance drain passage 112 and the retard control port 81 is maintained smaller than the flow area Fac between the advance return path 110 and the retard control port 81, and therefore between the elements 112, 81. The air becomes difficult to circulate regardless of the movement of the spool 73. Therefore, the effect of suppressing the situation where air is sucked into the advance recirculation passage 110 from the advance drain passage 112 through the retard control port 81 can be enhanced.

  According to the above, the advance angle recirculation passage 110 is switched both in the case of switching from the supply pressure operation to the recirculation operation in the second advance angle mode A2 and in the case of switching from the first advance angle mode A1 to the recirculation operation in the second advance angle mode A2. Air is less likely to be sucked into the advance chambers 52, 53, and 54. Therefore, it is possible to avoid the ramp-up of the vane rotor 15 due to the intake of air into the advance chambers 52, 53, 54, and to improve the advance response of the valve timing.

  When the second advance angle mode A2 is considered to correspond to the “connection mode” in the “phase change mode”, the first advance angle mode A1 is “in the phase change mode”. The advance angle control port 80 corresponds to the “introduction port”, the retard angle control port 81 corresponds to the “discharge port”, the direction Da corresponds to the “increase direction”, and the direction Dr corresponds to the “blocking mode”. This corresponds to “decreasing direction”.

(3) First retard angle mode R1
When operating conditions such as the rotational speed of the internal combustion engine being smaller than a predetermined value and the actual phase being on the advance side of the allowable deviation with respect to the target phase during steady operation, the first retard angle mode R1 shown in FIGS. A spool movement position is selected. In this spool movement position, the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are connected via the retard return passage 111 between the ports 80, 81, and Of these, the end portion 110 b on the opposite side to the retarded reflux passage 111 is closed by the sleeve 100. Further, in the retarded return passage 111, an end 111a on the retard control port 81 side is connected to the supply passage 62, and an end 110a on the advance control port 80 side is connected to the retard drain passage 113 and the drain recovery passage 65. Separated from.

  Under such a connection form, as shown in FIG. 10, when a positive torque of the variable torque acts on the vane rotor 15 to cause a rotational phase change that reduces the advance chambers 52, 53, 54, the advance chambers 52, 53 are generated. , 54 are pushed out through the advance control port 80 into the retarded return passage 111. At this time, the retarded angle return passage 111 connected to the retarded angle chambers 56, 57, 58 whose volume is expanded by the action of the positive torque via the retarded angle control port 81 and separated from the retarded angle drain passage 113, Recirculation that circulates to the retarded recirculation passage 111 side is permitted by the retarded recirculation check valve 121. On the other hand, in the advance recirculation passage 110 and the supply passage 62 connected to the retard recirculation passage 111, the advance recirculation check valve 120 and the supply flow check valve 130 are closed. Accordingly, in the retarded chambers 56, 57, and 58 where negative pressure is generated due to volume expansion, the retarded return passage 111 is in an amount corresponding to the flow area Frc of the discharged hydraulic oil from the advanced chambers 52, 53, and 54. Inhaled through. On the other hand, air is not sucked into the retarded angle chambers 56, 57 and 58 from the retarded drain passage 113 opened to the atmosphere through the retarded reflux passage 111. According to these, the valve timing can be retarded by changing the rotational phase to the retard side.

  Further, as shown in FIG. 11, when the direction of the variable torque is reversed and the negative torque acts on the vane rotor 15, if the retarded chambers 56, 57, and 58 try to reduce the volume, the retarded chamber is before the reversal. The hydraulic oil introduced into 56, 57, and 58 is pushed out into the retarded angle reflux passage 111. At this time, the reflux that flows to the advance control port 80 side in the retard return passage 111 is regulated by the retard return check valve 121. At the same time, the advance recirculation check valve 120 and the supply flow check valve 130 are closed in the advance recirculation passage 110 and the supply passage 62, respectively. According to the above, it is possible to suppress a situation in which the rotational phase changed to the retard side before the reversal of the variable torque returns to the advance side, so that it is possible to improve the delay response of the valve timing.

(4) Second retardation mode R2
When operating conditions such as the rotational speed of the internal combustion engine being larger than a predetermined value and the actual phase being on the advance side of the allowable deviation with respect to the target phase during steady operation, the second retard mode R2 shown in FIGS. A spool movement position is selected. In this spool movement position, the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are connected via the retard return passage 111 between the ports 80, 81, and Of these, the end portion 110 b on the opposite side to the retarded reflux passage 111 is closed by the sleeve 100. Further, of the retarded return passage 111, an end 111a on the retard control port 81 side is connected to the supply passage 62, and an end 111b on the advance control port 80 side is a retard drain passage between the ports 80 and 86. The drain recovery passage 65 is connected to the drain recovery passageway 65 through 113.

  Under such a connection configuration, the supply flow check valve 130 allows the supply flow toward the supply port 82 in the supply passage 62, so that the hydraulic oil supplied from the pump 4 is supplied to the supply port as shown in FIG. It circulates from 82 to the retard control port 81 side. At this time, when the supply pressure of the hydraulic oil from the pump 4 is equal to or higher than the set pressure as in the case (2), the retard control port is provided in the retard return passage 111 through which the hydraulic oil flows. The recirculation flowing from 81 to the advance control port 80 side is regulated by the retard recirculation check valve 121. At the same time, the advance recirculation check valve 120 is closed in the advance recirculation passage 110 connected to the retard recirculation passage 111. As a result, the hydraulic oil is introduced into the retard chambers 56, 57, 58 through the retard control port 81, and the hydraulic oil is advanced through the retard drain passage 113 connected to the advance control port 80. , 54 are sequentially discharged to the retarded drain port 86 and the drain collecting passage 65. According to the above supply pressure operation, under the operating conditions in which the responsiveness of the retarded recirculation check valve 121 becomes low due to the fluctuation torque being disturbed as the internal combustion engine rotates at a high speed (see FIG. 4), The hydraulic oil supplied from the pump 4 can be introduced into the retarded angle chambers 56, 57, 58 instead of the hydraulic oil discharged from the corner chambers 52, 53, 54. Therefore, the valve timing can be retarded by changing the rotational phase to the retard side regardless of the fluctuation of the fluctuation torque.

  However, when the supply pressure of the hydraulic oil becomes less than the set pressure due to the temperature rise, the operation of the recirculation check valves 120 and 121 according to the fluctuating torque is performed according to the recirculation operation of (3) above. As a result, hydraulic oil discharged from the advance chambers 52, 53, and 54 is introduced into the retard chambers 56, 57, and 58. According to this, even if the supply pressure of the hydraulic oil from the pump 4 is lowered, it is possible to continue the retardation of the valve timing.

  Here, in the recirculation operation in the second retard mode R2, the retard drain port 86 connected to the advance control port 80 via the retard drain passage 113 is opened to the atmosphere, so that the positive torque action as shown in FIG. Therefore, in the retard chambers 56, 57, and 58 in which negative pressure is generated, there is a concern about inhalation of air. However, independently of the retarded angle return passage 111 through which negative pressure propagates from the retarded angle chambers 56, 57, 58, the advanced angle control port 80 that opens the retarded angle drain passage 113 of the atmospheric pressure includes the advanced angle chamber 52, A positive pressure state is established by the inflow of hydraulic oil pushed out from 53 and 54. As a result, a situation in which air is sucked into the retarded recirculation passage 111 from the retarded drain passage 113 through the advance control port 80 can be suppressed. In addition, the flow area Frd between the retarded drain passage 113 and the advance control port 80 is maintained smaller than the flow area Frc between the retard return path 111 and the advance control port 80, so between the elements 111 and 80. The air becomes difficult to circulate regardless of the movement of the spool 73. Therefore, the effect of suppressing the situation in which air is sucked into the retarded recirculation passage 111 from the retarded drain passage 113 through the advance control port 80 can be enhanced.

  According to the above, even when the supply pressure operation is switched to the recirculation operation in the second retardation mode R2, or when the first retraction mode R1 is switched to the recirculation operation of the second retardation mode R2, the retardation recirculation passage 111 is provided. Air is less likely to be sucked into the retarding chambers 56, 57, and 58. Therefore, it is possible to avoid the ramp-up of the vane rotor 15 due to the intake of air into the retard chambers 56, 57, 58, and to improve the retard timing response of the valve timing.

  When the second retardation mode R2 is considered to correspond to the “connection mode” in the “phase change mode”, the first retardation mode R1 is “in the phase change mode”. The retard control port 81 corresponds to the “introduction port”, the advance control port 80 corresponds to the “exhaust port”, the direction Dr corresponds to the “increase direction”, and the direction Da corresponds to the “blocking mode”. This corresponds to “decreasing direction”.

(5) Holding mode H
When an operation condition such that the actual phase is within an allowable deviation with respect to the target phase is satisfied during steady operation, the spool movement position in the holding mode H shown in FIG. 15 is selected. In this spool movement position, the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58 are blocked from any of the advance return passage 110, the retard return passage 111, and the supply passage 62. The Under such a connection configuration, the hydraulic oil is held in the advance chambers 52, 53, 54 and the retard chambers 56, 57, 58, so that the valve is within the range of the rotational phase change due to the influence of the varying torque. Timing can be maintained.

  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. For example, the present invention is not limited to a device that adjusts the valve timing of an intake valve as a “valve”, but also a device that adjusts the valve timing of an exhaust valve as a “valve”, or both the intake valve and the exhaust valve. The present invention can also be applied to a device that adjusts timing.

1 Valve timing adjusting device, 2 cam shaft, 4 pump (supply source), 5 drain pan, 10 drive unit, 11 housing, 15 vane rotor, 15a rotating shaft, 52, 53, 54 advance chamber, 56, 57, 58 retard Chamber, 60 advance control passage, 61 retard control passage, 62 supply passage, 65 drain recovery passage, 70 control valve, 71 solenoid, 72 return spring, 73 spool, 73c outer peripheral surface, 80 advance control port, 80a, 81a Groove, 81 retard angle control port, 82 supply port, 85 advance angle drain port, 86 retard angle drain port, 90 control circuit, 100 sleeve, 100a inner peripheral surface, 110 advance angle return passage, 110c, 111c, 112c, 113c opening Part, 111 retarded return passage, 112 advanced drain passage, 113 retarded drain passage Road, 120 advance return check valve, 121 retard return check valve, 122 advance valve seat, 123 retard valve seat, 124 advance valve member, 125 retard valve member, 126 elastic member, 130 supply flow reverse Stop valve, A1 first advance mode, A2 second advance mode, H hold mode, R1 first retard mode, R2 second retard mode, Da direction, Dr direction, Fac, Fad, Frc, Frd , Sa1, Sa2, Sr1, Sr2 region

Claims (5)

A valve timing adjusting device for adjusting a valve timing of a valve that opens and closes a camshaft by torque transmission from a crankshaft in an internal combustion engine,
A housing that rotates in conjunction with the crankshaft;
By rotating in conjunction with the camshaft, the advance chamber and the retard chamber are partitioned in the rotation direction in the housing, and hydraulic fluid supplied from a supply source is introduced into the advance chamber or the retard chamber A vane rotor whose rotational phase with respect to the housing changes to an advance side or a retard side;
A control valve that controls entry and exit of hydraulic fluid to and from the advance chamber and the retard chamber according to the movement position of the spool accommodated in the sleeve,
The sleeve is
In the phase change mode for changing the rotational phase, an introduction port for introducing hydraulic fluid into one of the advance chamber and the retard chamber;
In the phase change mode, a discharge port through which hydraulic fluid is discharged from the other of the advance chamber and the retard chamber;
In the phase change mode, a supply port for circulating the hydraulic fluid supplied from the supply source to the introduction port side;
A drain port that is open to the atmosphere and discharges the working fluid;
The spool is
In the phase change mode, a reflux passage connecting the discharge port and the introduction port;
In the phase change mode, the hydraulic fluid flowing through the reflux passage from the discharge port to the introduction port side is allowed to return while the hydraulic fluid flowing through the return passage from the introduction port to the discharge port side is allowed to flow back. A return check valve to regulate,
In the phase change mode, having a drain passage connecting between the discharge port and the drain port,
In the phase change mode, hydraulic fluid that is secured between the return passage that opens toward the discharge port and the discharge port by moving in the increasing direction as one of the axial directions or the decreasing direction as the other. The flow area of the hydraulic fluid secured between the drain passage and the discharge port that opens independently of the reflux passage toward the discharge port is smaller than the flow area of the discharge port while maintaining a small relationship. A valve timing adjusting device characterized in that the flow area is increased or decreased together. The discharge port forms a groove extending in the circumferential direction along the inner peripheral surface of the sleeve,
The opening of the reflux passage and the opening of the drain passage are provided at locations that are shifted from each other in the circumferential direction on the outer peripheral surface of the spool, and open toward the groove in the phase change mode. The valve timing adjusting device according to claim 1. The spool is
By connecting the drain passage and the drain port by opening the drain passage toward the discharge port in the connection mode in the phase change mode,
Blocking between the discharge port and the drain port by closing the drain passage with respect to the discharge port in the blocking mode of the phase change mode,
3. The connection between the discharge port and the introduction port is established by opening the return passage toward the discharge port in both the connection mode and the cutoff mode. Valve timing adjustment device.   The spool moves in the increasing direction when switching from the shut-off mode to the connection mode, thereby opening the recirculation passage toward the discharge port before the drain passage. Item 4. The valve timing adjusting device according to Item 3. The discharge port forms a groove extending in the circumferential direction along the inner peripheral surface of the sleeve,
The opening portion of the reflux passage and the opening portion of the drain passage are provided at locations shifted from each other in the circumferential direction on the outer peripheral surface of the spool, and open toward the groove portion in the connection mode,
In the outer peripheral surface of the spool, the opening of the reflux passage is provided across a region overlapping with the opening of the drain passage along the axial direction and a region shifted from the overlapping region in the increasing direction. The valve timing adjusting device according to claim 4, wherein

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