JP2016031113A - Pressure control device and valve timing adjustment system using pressure control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure control device that prevents malfunction caused by catching a foreign object.SOLUTION: An opening communicating a sub-supply port 418 supplying a working fluid to an internal space 410 of a sleeve 41 with the internal space 410 is formed by opening end portions 441 and 442. A groove 436 is formed in an end portion 434 of a spool 43 sliding relatively to the opening end portion 441. When the groove 436 communicates with the sub-supply port 418, a foreign object contained in the working fluid flowing into the sub-supply port 418 is accumulated in the groove 436. When the groove 436 communicates with the internal space 410 by a reciprocating motion of the spool 43, the foreign object accumulated in the groove 436 is released into the internal space 410 by a flow of the working fluid between an inner wall 443 of an opening edge portion 441 and an outer wall 435 of the end portion 434. It is thereby possible to prevent the foreign object from being pinched between the inner wall 443 and the outer wall 435 and malfunction caused by catching the foreign object.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a pressure control device that controls the pressure of a working fluid supplied to an external device having a plurality of working fluid chambers into which working fluid flows in or out, and a valve timing adjustment system using the pressure control device.

  There is known a valve timing adjustment system capable of adjusting the valve timing of at least one of an intake valve and an exhaust valve of an engine. The valve timing adjustment system includes a housing that can rotate integrally with a crankshaft, a vane rotor that can rotate together with a camshaft, and changes the pressure of the advance chamber and retard chamber of the housing to rotate the vane rotor relative to each other. Adjust the valve timing.

  The pressure in the advance chamber and the retard chamber is controlled by a pressure control unit that controls the pressure of hydraulic oil supplied from an oil pump provided outside. The pressure control unit includes a sleeve having a plurality of ports, a spool that reciprocates within the sleeve, and the like. A supply port and a supply port to which hydraulic oil discharged from the oil pump is supplied depending on the relative position of the spool with respect to the sleeve Controls communication with other ports except for. For example, Patent Document 1 discloses a valve timing adjustment in which the spool is forcibly reciprocated in a state where the valve timing is held within a predetermined relatively narrow range, and foreign matter accumulated inside the sleeve is discharged to the outside. The system is described.

JP-A-9-165805

  The valve timing adjustment system described in Patent Document 1 has an inflow port through which a working fluid flows into a sleeve. Since the opening edge portion forming the inflow port and the sleeve are always slid, foreign matter accumulated in the opening edge portion cannot be discharged to the outside. For this reason, there is a possibility that the valve timing adjustment system may not operate reliably due to the biting of foreign matter, or the sliding surfaces of the sleeve and the spool may be damaged.

  The objective of this invention provides the pressure control apparatus which prevents the malfunctioning by the biting of a foreign material.

The present invention relates to a pressure control device that controls the pressure of a working fluid supplied to an external device having a plurality of working fluid chambers into which working fluid flows in or out, and includes a sleeve, a spool, a drive unit, and a control unit. Prepare.
The sleeve communicates with an external working fluid supply source, an inflow port through which the working fluid supplied to the plurality of working fluid chambers flows into the internal space, and a plurality of working fluid chambers communicated with the plurality of working fluid chambers of the external device And a drain port communicating with the inside of the working fluid reservoir for storing the working fluid. The spool is provided inside the sleeve so as to be capable of reciprocating in the central axis direction of the sleeve, and has a sliding portion that slides on an opening edge portion that forms an opening that communicates the inflow port and the internal space of the sleeve. The communication between the inflow port and the plurality of working fluid chamber communication ports is switched between and disconnected in accordance with the position in the central axis direction. The drive unit drives the spool. The control unit controls the operation of the drive unit.
The pressure control device of the present invention is characterized in that the sliding portion has a groove communicating with the inflow port when the spool moves in one direction and communicating with the drain port when the spool moves in the other direction.

  In the pressure control device of the present invention, the spool has a sliding portion that slides on the opening edge of the inflow port through which the working fluid flows into the internal space. A groove communicating with the inflow port or the drain port is formed in the sliding portion of the spool in accordance with the position of the spool. When the groove communicates with the inflow port, foreign substances contained in the working fluid flowing into the inflow port accumulate in the groove. When the groove communicates with the drain port by the movement of the spool, the foreign matter accumulated in the groove is discharged to the outside through the drain port by the flow of the working fluid. As a result, foreign matter accumulated in the vicinity of the opening edge of the inflow port can be discharged to the outside, and foreign matter can be prevented from being caught between the sleeve and the spool. Therefore, it is possible to prevent malfunction due to the biting of foreign matter.

It is sectional drawing of a valve timing adjustment system provided with the pressure control apparatus by 1st embodiment of this invention. It is II section sectional drawing of FIG. It is the III section enlarged view of FIG. It is a flowchart of the foreign material discharge | emission process in a valve timing adjustment system provided with the pressure control apparatus by 1st embodiment of this invention. It is sectional drawing explaining the effect | action of the foreign material discharge process in a valve timing adjustment system provided with the pressure control apparatus by 1st embodiment of this invention. It is sectional drawing explaining the effect | action of the foreign material discharge | emission process in a valve timing adjustment system provided with the pressure control apparatus by 1st embodiment of this invention, Comprising: It is sectional drawing explaining an effect | action different from FIG. It is a principal part enlarged view of a valve timing adjustment system provided with the pressure control apparatus by 2nd embodiment of this invention. It is sectional drawing explaining the effect | action of the foreign material discharge process in a valve timing adjustment system provided with the pressure control apparatus by 2nd embodiment of this invention. It is sectional drawing explaining the effect | action of the foreign material discharge | emission process in a valve timing adjustment system provided with the pressure control apparatus by 2nd embodiment of this invention, Comprising: It is sectional drawing explaining an effect | action different from FIG.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
1 and 2 show a valve timing adjustment system to which a pressure control device according to a first embodiment of the present invention is applied. The valve timing adjustment system 10 rotates a cam shaft 7 as a “driven shaft” and a “second shaft” relative to a crank shaft 6 as a “drive shaft” and “first shaft” of an internal combustion engine (not shown). The rotational phase of the camshaft 7 with respect to the crankshaft 6 is set, and the valve timing of an intake valve (not shown) that opens and closes the camshaft 7 is adjusted. The valve timing adjustment system 10 is provided in a driving force transmission system from the crankshaft 6 to the camshaft 7.

  The valve timing adjustment system 10 includes a phase adjustment unit 20 as an “external device” and a pressure control unit 1 as a “pressure control device”.

  The phase adjustment unit 20 includes a shoe housing 21, a rear plate 22, a front plate 23, a vane rotor 30, and the like. The shoe housing 21 and the front plate 23 correspond to a “housing” described in the claims. The rear plate 22 corresponds to a “timing pulley” described in the claims.

  The shoe housing 21 includes a cylindrical tube portion 211 and a plurality of shoes 212, 213, and 214. A rear plate 22 and a front plate 23 are provided at two ends of the cylindrical portion 211 in the central axis direction, respectively. The shoe housing 21, the rear plate 22, and the front plate 23 are fixed by three bolts 201, 202, and 203 (see FIG. 2) so that they cannot rotate relative to each other.

  The shoes 212, 213, and 214 protrude in the radially inward direction from a plurality of locations that are separated by a predetermined distance in the rotation direction of the cylindrical portion 211. The vanes 32, 33, and 34 included in the vane rotor 30 are positioned between the shoes 212, 213, and 214 that are adjacent to each other in the rotation direction.

  The rear plate 22 is provided so as to close one opening of the shoe housing 21. The rear plate 22 has a sprocket 221 that is connected to the crankshaft 6 via the timing chain 8. When the internal combustion engine is driven and the rotational torque generated by the internal combustion engine is transmitted from the crankshaft 6 to the sprocket 221, the shoe housing 21, the rear plate 22, and the front plate 23 are fixed in conjunction with the crankshaft 6. Rotate in the direction of.

  The front plate 23 is provided on the opposite side of the shoe housing 21 where the rear plate 22 is provided, and is provided so as to close the other opening of the shoe housing 21.

  A first locking pin 231 formed so as to protrude from the front plate 23 is provided on the opposite side of the front plate 23 from the shoe housing 21. The first locking pin 231 is eccentric and substantially parallel to the central axis Ac1 of the phase adjusting unit 20. In a boss portion 31 of the vane rotor 30 to be described later, an arm 314 is formed on a front boss portion 313 provided on the same side as the side on which the front plate 23 is provided with respect to the shoe housing 21 so as to face the front plate 23. , And a second locking pin 315 is provided. The second locking pin 315 is formed so as to protrude from the arm 314 toward the front plate 23, and is eccentric and substantially parallel to the central axis Ac1. The distance from the second locking pin 315 to the central axis Ac1 is the same as the distance from the first locking pin 231 to the central axis Ac1.

  An assist spring 26 is provided between the front boss portion 313 and the front plate 23. The assist spring 26 is a so-called spiral spring, and its center is provided on the central axis Ac1. An inner peripheral end 261 of the assist spring 26 is wound around the front boss 313. The outer peripheral side end 262 of the assist spring 26 can be locked to a pin corresponding to the rotational phase of the first locking pin 231 and the second locking pin 315.

  The outer peripheral side end 262 of the assist spring 26 is locked to the first locking pin 231 in a state where the rotational phase of the cam shaft 7 with respect to the crankshaft 6 is changed to the retard side with respect to the intermediate lock phase. At this time, since the second locking pin 315 is separated from the outer peripheral end 262, the vane rotor 30 is biased toward the advanced intermediate locking phase by the torsional elastic deformation of the assist spring 26. In the first embodiment, the urging force of the assist spring 26 that urges the vane rotor 30 to the advance side is set to be larger than the average value of the fluctuating torque biased to the retard side.

  Further, the outer peripheral side end 262 of the assist spring 26 is locked to the second locking pin 315 when the rotational phase of the cam shaft 7 with respect to the crankshaft 6 is changed to the advance side of the intermediate lock phase. Is done. At this time, since the first locking pin 231 is separated from the outer peripheral end 262, the urging of the assist spring 26 to the vane rotor 30 is limited.

  The vane rotor 30 is accommodated on the same axis as the central axis of the shoe housing 21 in an internal space formed by the shoe housing 21, the rear plate 22, and the front plate 23. Two ends of the vane rotor 30 in the central axis direction are provided so as to slide with the rear plate 22 and the front plate 23, respectively. The vane rotor 30 is formed of a cylindrical boss portion 31, a plurality of vanes 32, 33, 34, and the like.

  The boss part 31 includes a boss body part 311, a rear boss part 312 that is fastened to the camshaft 7 while passing through the rear plate 22 in the axial direction on the rear plate 22 side of the boss body part 311, and a front plate 23 side of the boss body part 311. Has a front boss portion 313 that opens through the front plate 23 in the axial direction. The boss portion 31 is fixed to the cam shaft 7. Thus, the vane rotor 30 is provided so as to be able to rotate in the same direction as the shoe housing 21 in conjunction with the cam shaft 7 and to be rotatable relative to the shoe housing 21.

The vanes 32, 33, and 34 are formed so as to protrude in the radially outward direction from a plurality of locations that are separated from each other by a predetermined distance in the circumferential direction of the boss main body portion 311 of the boss portion 31. The vanes 32, 33, and 34 are advance chambers 241, 242, and 243 as “working fluid chambers” into which hydraulic oil flows in or out between adjacent shoes 212, 213, and 214, and retard chambers 251, 252 and 253 are formed.
Specifically, an advance chamber 241 is formed between the shoe 212 and the vane 32, and a retard chamber 251 is formed between the vane 32 and the shoe 213. Further, an advance chamber 242 is formed between the shoe 213 and the vane 33, and a retard chamber 252 is formed between the vane 33 and the shoe 214. Further, an advance chamber 243 is formed between the shoe 214 and the vane 34, and a retard chamber 253 is formed between the vane 34 and the shoe 212.

  The vane 32 includes a “working fluid chamber” that houses a lock pin 28 as a “fixing member” that locks the rotational phase of the vane rotor 30 with respect to the front plate 23, and a lock pin housing chamber 321 as a “vane rotor chamber”. The hydraulic oil flows into or out of the lock pin housing chamber 321.

  On the other hand, the front plate 23 has a groove-shaped restriction hole 232 formed so as to extend in the rotation direction of the front plate 23, and a bottomed cylindrical hole-like lock that opens to the bottom surface of the advance side end portion of the restriction hole 232. A hole 233 is formed. (See FIG. 2). The restriction hole 232 and the lock hole 233 correspond to a “housing hole” described in the claims.

  The restriction hole 232 is formed between the lock pin accommodating chamber 321 and the central axis Ac1 in a restriction phase region from a predetermined phase between the most retarded angle phase and the most advanced angle phase to the most advanced angle phase in the valve timing adjustment system 10. Opposite the direction. Further, the lock hole 233 faces the lock pin housing chamber 321 in the direction of the central axis Ac1 in the intermediate lock phase.

  A lock spring 322 is accommodated in the lock pin accommodation chamber 321 coaxially with the lock pin 28. The lock spring 322 is provided between the retainer 323 fixed to the vane 32 and the lock pin 28. The lock spring 322 biases the lock pin 28 toward the front plate 23 side. The reciprocation of the lock pin 28 in the direction of the central axis Ac1 in the lock pin housing chamber 321 is controlled by the balance between the pressure of the hydraulic oil flowing into or out of the lock pin housing chamber 321 and the urging force of the lock spring 322.

  When the hydraulic oil is discharged from the lock pin housing chamber 321 in a state where the lock pin 28 is disengaged from both the restriction hole 232 and the lock hole 233, the lock pin 28 moves to the front plate 23 side and the restriction hole 232. Enter. After that, when the rotational phase regulated in the regulation phase region reaches the intermediate lock phase due to the action of fluctuation torque, the biasing force of the assist spring 26, etc., the lock pin 28 moves further to the front plate 23 side, and the lock hole 233 is fitted. Thereby, the rotation phase is locked at the intermediate lock phase.

  On the other hand, when hydraulic oil of a predetermined pressure or more is introduced into the lock pin housing chamber 321 in a state where the lock pin 28 is fitted in the lock hole 233, the lock pin 28 moves to the rear plate 22 side, and the restriction hole 232 and The lock hole 233 comes off. As a result, the lock and regulation of the rotational phase are released, and the valve timing can be freely adjusted according to the rotational phase.

  In the phase adjusting unit 20, the hydraulic oil flows into the advance chambers 241, 242, and 243 and the hydraulic oil from the retard chambers 251, 252, and 253 in a state where the lock of the rotational phase by the lock pin 28 is released. When spills out, the rotational phase changes to the advance side. The valve timing is advanced according to the change of the rotational phase toward the advance side. On the other hand, when the hydraulic oil flows out from the retard chambers 251, 252, 253 and the hydraulic fluid flows out from the retard chambers 251, 252, 253 in a state where the rotation phase is locked by the lock pin 28, The phase changes to the retard side. The valve timing is retarded according to the change of the rotational phase toward the retard side.

  Further, the phase adjusting unit 20 can set an intermediate lock phase as a rotation phase that ensures optimum startability of the internal combustion engine by fitting the lock pin 28 into the lock hole 233. When the rotational phase of the camshaft 7 with respect to the crankshaft 6 becomes an intermediate lock phase, the intake air amount to the cylinder when the internal combustion engine is started is prevented from excessively decreasing due to the closing delay of the intake valve, and the internal combustion engine is Start well.

  The pressure control unit 1 includes a sleeve bolt 41 as a “sleeve”, a spool 43, a solenoid 45 as a “drive unit”, a control unit 47, and the like.

  The sleeve bolt 41 is accommodated in the boss portion 31. The sleeve bolt 41 is formed in a substantially cylindrical shape and includes a head portion 411, a screw portion 412 and the like. As shown in FIG. 1, the sleeve bolt 41 includes a first drain port 413, an advance port 414, and a main supply port 415 in order from the axial end of the head 411 toward the axial end of the screw portion 412. , A retard port 416, a lock port 417, a sub supply port 418 as an “inflow port”, and a second drain port 419 as a “drain port”. Among these, the first drain port 413 and the second drain port 419 are respectively formed at two axial ends of the sleeve bolt 41. The advance port 414, the retard port 416, and the lock port 417 correspond to the “working fluid chamber communication port” recited in the claims.

The head portion 411 is formed in a cylindrical shape so as to extend in the central axis direction of the cam shaft 7 at the boss portion 31. The head 411 has an internal space 410 as an “internal space of the sleeve” formed so as to extend in the direction of the central axis Ac 1 of the sleeve bolt 41. The internal space 410 includes a first drain port 413, an advance port 414, a main supply port 415, a retard port 416, a lock port 417, a sub supply port 418, and a screw portion 412 formed on the outer wall of the head 411. The 2nd drain port 419 currently formed inside is communicating. In the internal space 410, the spool 43 is slidably accommodated.
The screw part 412 is formed in a substantially cylindrical shape having a smaller outer diameter than the head part 411. The threaded portion 412 is screwed to the inner wall of the cam shaft 7 when the sleeve bolt 41 is inserted into the cam shaft 7. Thereby, the sleeve bolt 41 rotates integrally with the cam shaft 7.

The first drain port 413 is formed at the end of the head 411 opposite to the side connected to the threaded portion 412. The first drain port 413 communicates with the inside of the oil pan 12 as a “working fluid reservoir” via the reflux oil passage 11. The first drain port 413 returns the hydraulic oil in the internal space 410 to the oil pan 12.
The advance port 414 communicates with the advance main passage 35 of the front boss 313. The advance main passage 35 communicates with advance branch passages 351, 352, 353 communicating with the corresponding advance chambers 241, 242, 243, respectively.
The main supply port 415 communicates with the oil pump 15 as a “working fluid supply source” via the main supply passage 36 included in the boss body 311 and the supply oil passage 14 communicating with the main supply passage 36. A reed check valve 361 is provided in the middle of the main supply passage 36. The oil pump 15 is a mechanical pump that is driven by the crankshaft 6 as the internal combustion engine is driven. The oil pump 15 continuously discharges hydraulic oil sucked from the oil pan 12 while the internal combustion engine is driven.
The retard port 416 communicates with the retard main passage 37 included in the boss body 311. The retard main passage 37 communicates with retard branch passages 371, 372, and 373 communicating with the corresponding retard chambers 251, 252, and 253, respectively.
The lock port 417 communicates with the lock pin accommodating chamber 321 through the lock operation passage 38 of the boss portion 31.
The sub supply port 418 communicates with a sub supply passage 39 that communicates with the main supply passage 36. The sub supply port 418 flows hydraulic oil supplied from the oil pump 15 through the sub supply passage 39 into the internal space 410. A reed check valve 391 is provided in the middle of the sub supply passage 39.
The second drain port 419 is formed from the end of the head portion 411 on the screw portion 412 side to the screw portion 412. The second drain port 419 communicates with the inside of the oil pan 12 through the reflux oil passage 13. The second drain port 419 returns the hydraulic oil in the internal space 410 to the oil pan 12.

  The spool 43 is accommodated in the internal space 410 so as to be reciprocally movable. The spool 43 is in contact with the rod 46 of the solenoid 45 described later at the end on the head 411 side. Further, one end of the spring 44 is in contact with the end portion on the screw portion 412 side. The other end of the spring 44 is in contact with the inner wall of the sleeve bolt 41 and urges the spool 43 in a direction away from the screw portion 412. The position of the spool 43 with respect to the sleeve bolt 41 is determined by the balance between the driving force of the rod 46 and the biasing force of the spring 44.

  The spool 43 has an internal oil passage 430 in the central axis direction. The internal oil passage 430 has openings 431 and 432 at two axial end portions on the head portion 411 side and two axial end portions on the screw portion 412 side. The spool 43 includes a plurality of radial communication passages 433 that are formed in the radial direction and communicate with the internal oil passage 430. The radial communication path 433 is formed so as to be able to communicate with at least one of the retard port 416 and the lock port 417 according to the movement position of the spool 43. The spool 43 selectively communicates a plurality of ports of the sleeve bolt 41 according to the position in the direction of the central axis Ac1 to change the rotation phase.

  The solenoid 45 is provided on the side opposite to the shoe housing 21 with respect to the front plate 23. The solenoid 45 is provided so that the rod 46 included in the solenoid 45 abuts on the end portion on the head 411 side that can protrude from the first drain port 413 of the spool 43. The solenoid 45 generates a driving force in the direction of the central axis Ac1 according to the magnitude of the output current output from the control unit 47. The relative position of the spool 43 with respect to the sleeve bolt 41 is controlled by the driving force.

  The control unit 47 is configured by a microcomputer including a CPU, a ROM, a RAM, an input / output port, and the like. The controller 47 determines the magnitude of the output current output to the solenoid 45 in response to a command related to valve timing from a host vehicle operation controller (not shown).

  The pressure control unit 1 controls the relative position of the spool 43 with respect to the sleeve bolt 41 by the control unit 47 and the solenoid 45, and the advance chambers 241, 242, 243, the retard chambers 251, 252, 253, and the lock pin housing chamber The inflow or outflow of the hydraulic oil to 321 is controlled. Thereby, the relative rotation angle of the vane rotor 30 with respect to the shoe housing 21 in the phase adjustment unit 20 is controlled, and the rotation phase of the cam shaft 7 with respect to the crankshaft 6 is controlled.

  Next, a valve timing adjustment method in the valve timing adjustment system 10 will be described. As the moving direction of the spool 43, when the spool 43 moves to the solenoid 45 side in FIG. 1, it moves to the “advance side” as “one direction”, and in FIG. 1, the spool 43 moves to the screw part 412 side. It is assumed that the time is moved to the “retard side” as the “other direction”.

(1) Advance angle operation In the internal combustion engine being driven, the actual rotational phase of the camshaft 7 relative to the crankshaft 6 (hereinafter referred to as “camshaft actual phase”) is the target rotational phase of the camshaft 7 relative to the crankshaft 6 (hereinafter referred to as “ When an operation condition such as being on the retard side with respect to the allowable deviation with respect to the “cam shaft target phase” is established, the control unit 47 controls the duty ratio of the output current output to the solenoid 45 to move the spool 43 to the advance side. Moving. When the spool 43 moves to the advance side, the advance port 414 communicates with the main supply port 415, and hydraulic oil flows into the advance chambers 241, 242, and 243. Further, the retard port 416, the first drain port 413, and the second drain port 419 communicate with each other via the radial communication passage 433 and the internal oil passage 430, and the hydraulic oil flows out from the retard chambers 251, 252, and 253. . At this time, since the lock port 417 and the sub supply port 418 communicate with each other, the hydraulic oil flows into the lock pin accommodating chamber 321. Thereby, the valve timing is changed to the advance side.

(2) Holding operation When the operating condition such as the actual camshaft phase being within the allowable deviation from the camshaft target phase is satisfied in the internal combustion engine being driven, the control unit 47 sets the duty ratio of the output current output to the solenoid 45. The spool 43 is moved so that the advance port 414 and the retard port 416 are blocked from other ports. As a result, hydraulic oil is retained in the advance chambers 241, 242, 243 and the retard chambers 251, 252, 253. At this time, since the lock port 417 and the sub supply port 418 communicate with each other, the hydraulic oil flows into the lock pin accommodation chamber 321. As a result, the valve timing is maintained.

(3) Retardation operation When an operating condition such as the actual camshaft phase being on the advance side with respect to the camshaft target phase is satisfied in the internal combustion engine being driven, the control unit 47 outputs to the solenoid 45. The duty ratio of the current is controlled to move the spool 43 to the retard side. When the spool 43 moves to the retard side, the advance port 414 communicates with the first drain port 413 and the second drain port 419 via the radial communication passage 433 and the internal oil passage 430, and the advance chambers 241, 242. , Hydraulic oil flows out from H.243. Further, the retard port 416 and the main supply port 415 communicate with each other, and hydraulic oil flows into the retard chambers 251, 252, and 253. At this time, since the lock port 417 and the sub supply port 418 communicate with each other, the hydraulic oil flows into the lock pin accommodating chamber 321. As a result, the valve timing is changed to the retard side.

(4) Locking operation In the driving internal combustion engine, for example, at the time of idling operation in which the hydraulic oil pressure decreases, the control unit 47 sets the duty ratio of the output current output to the solenoid 45 to 0%. When the duty ratio of the output current is 0%, the advance port 414 and the main supply port 415 communicate with each other, and hydraulic oil whose flow rate is reduced by the gap between the inner wall of the sleeve bolt 41 and the outer wall of the spool 43 advances. It flows into the corner chambers 241, 242, 243. Further, the retard port 416, the first drain port 413, and the second drain port 419 communicate with each other via the radial communication passage 433 and the internal oil passage 430, and the hydraulic oil flows out from the retard chambers 251, 252, and 253. . At this time, the lock port 417, the first drain port 413, and the second drain port 419 communicate with each other via the radial communication path 433 and the internal oil path 430, and the hydraulic oil flows out from the lock pin accommodating chamber 321.

  The vane rotor 30 receives the rotational force generated by the inflow of hydraulic oil into the advance chambers 241, 242, and 243 and the restoring force of the assist spring 26 in the advance direction shown in FIG. 2 fluctuate on average, and the bias torque acts in the retard direction shown in FIG. When these forces act on the vane rotor 30, the lock pin 28 is fitted into the restriction hole 232, and the rotation phase is restricted to be within the restriction phase region. As a result, the lock pin 28 is easily fitted into the lock hole 233 at the intermediate lock phase in the regulation phase region, and the rotation phase can be reliably locked during the driving of the internal combustion engine.

(5) Stop operation When driving of the internal combustion engine is stopped in response to a stop command from the vehicle operation control unit or the like, the control unit 47 sets the duty ratio of the output current output to the solenoid 45 to 0%. Thus, as in the lock operation, the advance port 414 communicates with the main supply port 415, and the hydraulic oil squeezed by the gap between the inner wall of the sleeve bolt 41 and the outer wall of the spool 43 is moved to the advance chamber 241. 242 and 243. Further, the retard port 416 and the lock port 417 communicate with the first drain port 413 and the second drain port 419, and hydraulic oil flows out from the retard chambers 251, 252 and 253 and the lock pin accommodation chamber 321. As a result, in the intermediate lock phase within the regulation phase region, the lock pin 28 is easily fitted into the lock hole 233, and the rotation phase can be reliably locked until the rotation of the internal combustion engine completely stops. It is.

(6) Start operation When the internal combustion engine is started in response to a start command from the vehicle operation control unit or the like, the control unit 47 moves the spool 43 to the advance side by controlling the duty ratio of the output current output to the solenoid 45. To do. When the spool 43 is moved, the advance port 414 and the main supply port 415 communicate with each other, and a larger amount of hydraulic oil flows into the advance chambers 241, 242, and 243 than during the lock operation. Further, the retard port 416 and the lock port 417 communicate with the first drain port 413 and the second drain port 419, and hydraulic oil flows out from the retard chambers 251, 252 and 253 and the lock pin accommodation chamber 321. That is, at the time of starting operation, the flow rate of the hydraulic oil flowing into the advance chambers 241, 242, and 243 is locked while maintaining the state where the hydraulic oil flows out from the retard chambers 251, 252, and 253 and the lock pin housing chamber 321. It is controlled to be more than the time. Thus, during the start-up period, the hydraulic oil flows into the advance chambers 241, 242, and 243 while maintaining the intermediate lock phase, so that it is possible to prepare for the advance operation.

  The valve timing adjustment system 10 to which the pressure control device according to the first embodiment is applied is characterized by the shape of the portion of the spool 43 that slides with the inner wall of the sleeve bolt 41 in the vicinity of the sub supply port 418. Here, the shape of the spool 43 will be described with reference to FIG.

  FIG. 3 is an enlarged cross-sectional view of the vicinity of a portion where the sub supply port 418 is formed. The sub supply port 418 is formed so as to be able to communicate with the internal space 410 of the sleeve bolt 41, and an opening edge portion that forms an opening that connects the sub supply port 418 and the internal space 410 to the inner wall of the sleeve bolt 41. Is provided. Here, for convenience, the opening edge on the second drain port 419 side is defined as an opening edge 441, and not only the opening that connects the sub supply port 418 and the internal space 410 but also the lock port 417 and the internal space 410 are connected. An opening edge portion that forms the opening to be opened is referred to as an opening edge portion 442.

  An end 434 of the spool 43 located in the vicinity of the sub supply port 418 is formed in a bottomed cylindrical shape. The inside of the end portion 434 communicates with an internal oil passage 430 included in the spool 43. The end portion 434 corresponds to a “sliding portion” described in the claims.

  An outer wall 435 radially outside the end portion 434 is slidably provided on the opening edge portions 441 and 442. The outer wall 435 is provided with a recess 437 that forms a groove 436.

  Foreign matter contained in the hydraulic fluid flowing from the sub supply passage 39 to the sub supply port 418 flows through the opening that connects the sub supply port 418 and the internal space 410. As shown in FIG. 5, even if the sub supply port 418 and the internal space 410 are blocked by the spool 43, the opening edge 441 and the inner wall 443 are provided to slide, so that the inner wall 443 of the opening edge 441 is provided. A gap through which hydraulic oil can flow is formed between the outer wall 435 and the outer wall 435 of the end portion 434. That is, the hydraulic oil flowing into the sub supply port 418 flows through the gap into the internal space 410 on the side opposite to the sub supply port 418 with respect to the opening edge 441. As a result, the foreign matter A1 contained in the hydraulic oil flowing through the sub supply port 418 is caused to flow by the flow of the hydraulic oil as indicated by an arrow Fa5 in FIG.

  In the valve timing adjustment system 10 to which the pressure control device according to the first embodiment is applied, the foreign matter accumulated in the vicinity of the opening communicating the sub supply port 418 and the internal space 410 is discharged to the outside according to the flowchart shown in FIG. Hereinafter, the foreign matter discharge processing will be described with reference to FIGS.

The foreign matter discharge processing of the valve timing adjustment system 10 is continuously executed according to the flowchart shown in FIG. 4 while the internal combustion engine is driven.
First, in step (hereinafter referred to as “S”) 101, the control unit 47 determines whether or not the output current output to the solenoid 45 is within a predetermined range. In the valve timing adjustment system 10, for example, when a vehicle equipped with the valve timing adjustment system 10 is traveling on a highway, the valve timing of the intake valve hardly changes. At this time, since the output current output from the control unit 47 hardly changes, the output current is controlled within a predetermined range. When the output current output by the controller 47 is within a predetermined range, the movement range of the spool 43 relative to the sleeve bolt 41 is “within a predetermined movement range” described in the claims. Therefore, in S101, for example, the control unit 47 determines that the output current is within a predetermined range with almost no hydraulic oil flowing into the advance chambers 241, 242, and 243 and the retard chambers 251, 252, and 253. If it determines, it will progress to S102. For example, when the control unit 47 determines that the output current is out of a predetermined range in a state where a large amount of hydraulic oil flows into the advance chambers 241, 242, 243 or the retard chambers 251, 252, 253, This foreign matter discharge process is terminated.

  Next, in S102, the time elapsed after the output current is within a predetermined range (hereinafter referred to as “elapsed time”) is counted.

  Next, it is determined whether or not the elapsed time counted in S103 is longer than a predetermined time. The control unit 47 determines whether or not the time after the output current output from the control unit 47 to the solenoid 45 is within a predetermined range is longer than the predetermined time. If the controller 47 determines that the elapsed time is longer than the predetermined time, the process proceeds to S104. When the controller 47 determines that the elapsed time is equal to or less than the predetermined time, the current foreign matter discharge process is terminated.

Next, in S104, foreign matter discharge control is executed. Specifically, the control unit 47 outputs an output current to the solenoid 45 so that the position of the spool 43 with respect to the sleeve bolt 41 changes from the state of FIG. 5 to the state of FIG. At this time, when the length of the groove 436 in the axial direction is the length D and the moving distance S of the spool 43 is the length L in the axial direction of the inner wall 443 of the opening edge 441 that slides with the outer wall 435 of the end 434. Is represented by equation (1).
D <L <S (1)
In the spool 43 moved by the moving distance S in the direction of the white arrow WF6 shown in FIG. 6, the groove 436 communicates with the internal space 410 as shown in FIG. The foreign matter A1 accumulated in the groove 436 is discharged into the internal space 410 as indicated by an arrow Fa6 in FIG. 6 by the flow of hydraulic oil passing through the gap between the inner wall 443 and the outer wall 435. The foreign matter A1 discharged into the internal space 410 is discharged outside the pressure control unit 1 through the second drain port 419.

  Next, in S105, the elapsed time counted in S102 is reset, and the elapsed time is set to zero. Thus, the current foreign matter discharge process is terminated.

  (A) In the valve timing adjustment system 10 including the pressure control unit 1 according to the first embodiment, the spool 43 has an end portion 434 that slides on the opening edge portion 441 of the sub supply port 418 through which hydraulic fluid always flows. ing. That is, the opening edge 441 is a bearing for the end 434 for the spool 43 to reciprocate with respect to the sleeve bolt 41. When the groove 436 formed in the outer wall 435 of the end portion 434 communicates with the sub supply port 418, the foreign matter A1 contained in the hydraulic oil flowing through the sub supply port 418 accumulates. The foreign matter A1 accumulated in the groove 436 is discharged into the internal space 410 when the internal space 410 and the groove 436 communicate with each other by the reciprocating movement of the spool 43 in the foreign matter discharging process. Thereby, the foreign matter A1 accumulated in the vicinity of the opening that communicates the sub supply port 418 and the internal space 410 can be discharged to the outside of the pressure control unit 1 via the second drain port 419. Therefore, the foreign matter A1 can be prevented from being caught between the sleeve bolt 41 and the spool 43, and malfunction due to the foreign matter A1 being caught can be prevented.

  (B) Further, since foreign matter can be prevented from entering the sliding surface between the sleeve bolt 41 and the spool 43, it is possible to prevent the sliding surface from being damaged by the foreign matter that has entered the sliding surface. . Therefore, it is possible to prevent the performance degradation of the valve timing adjustment system 10 including the pressure control unit 1.

  (C) In addition, foreign matter tends to accumulate at a specific location in a time zone when the valve timing of the intake valve is not frequently adjusted. If the foreign matter is not reliably discharged, the pressure control unit may malfunction due to the foreign matter being caught. is there. In the valve timing adjustment system 10, when the output current output to the solenoid 45 is within a predetermined range and the time elapsed after the output current is within the predetermined range becomes longer than the predetermined time, The spool 43 is moved to the retard side to execute foreign matter discharge control. As a result, foreign matter can be reliably discharged according to the degree of foreign matter accumulation.

(Second embodiment)
Next, a pressure control device according to a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is different from the first embodiment in the number of grooves to be formed and the place where the grooves are formed. In addition, the same code | symbol is attached | subjected to the site | part substantially the same as 1st embodiment, and description is abbreviate | omitted.

  The valve timing adjustment system including the pressure control device according to the second embodiment has two grooves 436 and 438 at the end 434 of the spool 43. The concave portion 437 that forms the groove 436 and the concave portion 439 that forms the groove 438 are provided so as to be aligned in the direction in which the spool 43 reciprocates.

  In the valve timing adjustment system of the second embodiment, the communication destinations of the two grooves 436 and 438 are changed according to the magnitude of the output current output from the control unit 47. Hereinafter, foreign matter discharge processing in the valve timing adjustment system of the second embodiment will be described with reference to FIGS.

  In the valve timing adjustment system of the second embodiment, when the internal combustion engine provided with the valve timing adjustment system is in an idling state, the control unit 47 sets the duty ratio of the output current output to the solenoid 45 to 0%. At this time, in the valve timing adjustment system of the second embodiment, the valve timing is maintained at the intermediate lock phase. In a state where the intermediate lock phase is maintained, the two grooves 436 and 438 communicate with the sub supply port 418 as shown in FIG. Since the hydraulic oil supplied from the oil pump 15 flows into the sub supply port 418 from the sub supply passage 39, the foreign matter contained in the hydraulic oil communicates between the sub supply port 418 and the internal space 410 as indicated by the arrow Fa7. It is easy to gather near the opening. The foreign matter A2 that collects in the vicinity of the opening mainly accumulates in the groove 436 near the opening edge 441 because the hydraulic oil flows through the gap between the opening edge 441 and the end 434.

  In the valve timing adjustment system of the second embodiment, when the internal combustion engine provided with the valve timing adjustment system shifts from the idling state to the traveling state, the valve timing of the intake valve changes from the intermediate lock phase to the advance side or the retard side. Be changed.

  In the second embodiment, when the valve timing of the intake valve is changed from the intermediate lock phase to the advance side, the control unit 47 sets the duty ratio of the output current output to the solenoid 45 to 40%, for example. At this time, as shown in FIG. 8, the spool 43 moves from the state of FIG. 7 in the direction of the white arrow WF8. Due to the movement of the spool 43, the groove 436 in which the foreign matter A 2 is accumulated communicates with the internal space 410 on the side opposite to the sub supply port 418 with respect to the opening edge 441. When the groove 436 communicates with the internal space 410, the foreign matter A2 accumulated in the groove 436 is discharged into the internal space 410 (arrow Fa8 in FIG. 8). At this time, the groove 438 is located on the side of the sub supply port 418 with respect to the opening edge 441 and communicates with the sub supply port 418. As a result, the foreign matter B2 contained in the hydraulic oil flowing through the sub supply port 418 accumulates in the groove 438 (arrow Fb8 in FIG. 8).

  In the second embodiment, when the valve timing of the intake valve is changed to the retard side, the control unit 47 sets the duty ratio of the output current output to the solenoid 45 to 100%, for example. At this time, as shown in FIG. 9, the spool 43 moves from the state of FIG. 7 or the state of FIG. 8 in the direction of the white arrow WF9. Due to the movement of the spool 43, the groove 438 in which the foreign matter B2 is accumulated communicates with the internal space 410 opposite to the sub supply port 418 with respect to the opening edge 441. When the groove 438 communicates with the internal space 410, the foreign matter B2 accumulated in the groove 438 is discharged into the internal space 410 (arrow Fb9 in FIG. 9). At this time, the groove 436 is located on the opposite side of the opening edge 441 from the sub supply port 418 and communicates with the internal space 410.

  The valve timing adjustment system including the pressure control device according to the second embodiment has a plurality of grooves that can collect foreign substances contained in the hydraulic oil. The plurality of grooves are formed so as to be aligned in the direction in which the spool 43 reciprocates. The plurality of grooves communicate with the sub supply port 418 or the internal space 410 according to the position of the spool 43 with respect to the sleeve bolt 41 while the valve timing adjustment system of the second embodiment adjusts the valve timing of the intake valve. Specifically, when the valve timing is changed from the intermediate lock phase to the advance angle or the retard angle, or when the valve timing is changed from the advance angle to the retard angle, the two grooves 436, 438 are formed in the sub supply port 418 or the internal Foreign substances A2 and B2 communicating with the space 410 and accumulated in the grooves 436 and 438 are discharged into the internal space 410. Thereby, in the adjustment of the normal valve timing, it is possible to prevent foreign matter from being sandwiched between the opening edge portion 441 and the end portion 434 that are always sliding, and reliably discharged to the outside. Therefore, the second embodiment has the effects (a) and (b) of the first embodiment, and can discharge foreign matters in normal valve timing control without performing special control.

(Other embodiments)
(A) In the above-described embodiment, the pressure control unit as the “pressure control device” is applied to the valve timing adjustment system. However, the system to which the “pressure control device” is applied is not limited to this. For example, it may be used in a hydraulic oil pressure control unit that controls the operation of a plurality of clutches of an automatic transmission.

  (A) In the above-described embodiment, the valve timing adjustment system adjusts the valve timing of the intake valve. However, it may be applied to the adjustment of the valve timing of the exhaust valve.

  (C) In the first embodiment, when the spool moves to the advance side as “one direction”, the groove communicates with the sub supply port, and the spool moves to the retard side as “other direction”. At that time, it was supposed to communicate with the internal space communicating with the drain port. However, “one direction” and “other direction” are not limited to this. In the reciprocating movement of the spool, “one direction” may be set as one direction of movement, and a direction opposite to the one direction may be set as “other direction”.

  (D) In the first embodiment, one groove is formed. In the second embodiment, two grooves are formed. However, the number of grooves formed is not limited to this. A plurality of spools may be formed in the circumferential direction at the threaded portion side end.

  (E) In the above-described embodiment, the sleeve bolt and the spool of the pressure control unit as the “pressure control device” are provided inside the phase adjustment unit. However, the sleeve bolt and the spool may be provided outside the phase adjustment unit.

  (F) In the above-described embodiment, the crankshaft is the first axis and the camshaft is the second axis. However, the crankshaft may be the second axis and the camshaft may be the first axis.

  As mentioned above, this invention is not limited to such embodiment, It can implement with a various form in the range which does not deviate from the summary.

1 ... Pressure control part (pressure control device),
10: Valve timing adjustment system,
12: Oil pan (working fluid reservoir),
15 ... Oil pump (working fluid supply source),
20 ... Phase adjustment unit (external device),
241, 242, 243 ... advance chamber (working fluid chamber),
251, 252, 253 ... retarding chamber (working fluid chamber),
41 ... Sleeve bolt (sleeve),
410 ・ ・ ・ Space (inner space of the sleeve),
414 ... Advance port (working fluid chamber communication port),
416 ... retarding port (working fluid chamber communication port),
417 ... Lock port (working fluid chamber communication port),
418... Sub supply port (inflow port),
419 ... second drain port (drain port),
43 ・ ・ ・ Spool,
434... Sliding part,
436, 438 ... grooves.
441 ... opening edge,
45 ・ ・ ・ Solenoid (drive unit),
47: Control unit.

Claims (7)

A pressure control device (1) for controlling the pressure of the working fluid supplied to the external device (20) having a plurality of working fluid chambers (241, 242, 243, 251, 252, 252, 321) into which the working fluid flows in or out. ) And
An inflow port (418) that communicates with an external working fluid supply source (15) and flows into the internal space (410) with working fluid supplied to the plurality of working fluid chambers, and a plurality of the working fluid chambers of the external device A plurality of working fluid chamber communication ports (414, 416, 417) communicating with the sleeve (41), and a sleeve (41) having a drain port (419) communicating with the inside of the working fluid reservoir (12) for storing the working fluid;
A sliding portion (434) that slides on an opening edge portion (441) that is provided inside the sleeve so as to reciprocate in the central axis direction of the sleeve and forms an opening that communicates the inflow port and the internal space. A spool (43) for switching communication and blocking between the inflow port and the plurality of working fluid chamber communication ports in correspondence with a position in the central axis direction of the sleeve;
A drive unit (45) for driving the spool;
A control unit (47) for controlling the operation of the drive unit;
With
The sliding portion has grooves (436, 438) communicating with the inflow port when the spool moves in one direction and communicating with the drain port when the spool moves in the other direction. Control device.   2. The drive unit according to claim 1, wherein the drive unit drives the spool to communicate the groove with the drain port when a state in which the movement range of the spool is within a predetermined movement range continues for a predetermined time. The pressure control apparatus as described. A valve timing adjustment system (10) that is provided in a driving force transmission system that transmits a driving force from the driving shaft (6) to the driven shaft (7) of the internal combustion engine and adjusts the valve timing of the valve that is driven to open and close by the driven shaft. Because
As one first axis of the drive shaft and the driven shaft, and the other second axis,
A timing pulley (22) rotatable integrally with the first shaft; housings (21, 23) provided integrally with the timing pulley; and the housing fixed to an end of the second shaft inside the housing A phase adjustment section (20) as the external device having a vane rotor (30) that partitions the interior of the chamber into an advance chamber and a retard chamber as the working fluid chamber;
The pressure control device according to claim 1 or 2,
A valve timing adjustment system comprising:   The pressure control device according to claim 1, wherein a plurality of the grooves are formed in a reciprocating direction of the spool.   The control unit communicates the plurality of grooves with the inflow port when the spool moves in one direction, and communicates the plurality of grooves with the drain port when the spool moves in the other direction. The pressure control device according to claim 4. A valve timing adjustment system (10) that is provided in a driving force transmission system that transmits a driving force from the driving shaft (6) to the driven shaft (7) of the internal combustion engine and adjusts the valve timing of the valve that is driven to open and close by the driven shaft. Because
As one first axis of the drive shaft and the driven shaft, and the other second axis,
A timing pulley (22) rotatable integrally with the first shaft; housings (21, 23) provided integrally with the timing pulley; and the housing fixed to an end of the second shaft inside the housing A phase adjustment section (20) as the external device having a vane rotor (30) that partitions the interior of the chamber into an advance chamber and a retard chamber as the working fluid chamber;
A pressure control device (40) according to claim 4 or 5,
A valve timing adjustment system comprising: The valve timing of the valve is set to a predetermined value when it is reciprocally accommodated in a vane rotor chamber (321) as the working fluid chamber formed in the vane rotor and is fitted in housing holes (232, 233) formed in the housing. A fixing member (28) for fixing the rotational phase of the vane rotor with respect to the timing pulley so as to have timing;
When the fixing member is fitted in the housing hole, the plurality of grooves communicate with the sub supply port as the inflow port into which the working fluid supplied to the vane rotor chamber flows,
When the fitting of the fixing member into the housing hole is released and the valve timing is advanced from the predetermined timing, one groove (436) of the plurality of grooves communicates with the drain port. The other groove (438) of the plurality of grooves communicates with the inflow port,
The plurality of grooves communicate with the drain port when the fitting of the fixing member into the housing hole is released and the valve timing is retarded from the predetermined timing. The valve timing adjustment system described.

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