Fluid control valve unit and valve timing change device

Abstract

To secure a smooth motion of a fluid control valve unit.SOLUTION: A fluid control valve unit U includes: a fluid control valve V including a bottomed cylindrical sleeve 70 defining an axis S and a spool 80 accommodated in the sleeve so as to be slidable in an axial direction; a cylindrical passage member 50 having an internal peripheral face 51 with which the sleeve fits, a receiving part 53 for receiving an end part 70a of the sleeve in the axial direction, and an annular groove part 59b which is recessed relative to the internal peripheral face; and a snap ring 110 which has a notched part 110a with a prescribed clearance and which is embedded into the annular groove part such that it regulates falling of the fluid control valve accommodated in the passage member in the axial direction and allows discharge of fluid flowing in a discharge passage formed in the passage member.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a fluid control valve unit and a valve timing change device for an internal combustion engine using the same. [Background technology]

[0002] A known conventional fluid control valve unit includes a cylindrical outer sleeve having a hydraulic oil passage and open at both ends, a cylindrical inner sleeve with a bottom that has an inlet for the hydraulic oil to flow in and an outlet for the hydraulic oil to flow out and is inserted into the outer sleeve, a spool inserted into the inner sleeve so as to be able to move back and forth, a biasing spring that biases the spool in one of the movement directions, a filter member fitted to the inner wall surface at one end of the outer sleeve, and a cap-shaped locking member fitted to the inner wall surface at the other end of the outer sleeve (see, for example, Patent Document 1).

[0003] In this fluid control valve unit, the filter member is fitted onto the inner wall surface of the outer sleeve, the inner sleeve is inserted into the outer sleeve so as to abut against the filter member, and with the spring and spool inserted into the inner sleeve, the locking member is fitted onto the inner wall surface of the outer sleeve so as to cooperate with the filter member to clamp and fix the inner sleeve and prevent the spool from falling off.

[0004] Here, the locking member must clamp and fix the inner sleeve, prevent the spool from falling off, and allow excess hydraulic oil inside the outer sleeve to be discharged to the outside. However, because the locking member and filter member are structured to fit onto the inner wall surface of the outer sleeve, there is a risk that the locking member or filter member may fall off due to impact from the reciprocating movement of the spool, deterioration over time, etc. Furthermore, although the shape of the locking member is not clear, there is a risk that the hydraulic oil may not be discharged smoothly depending on the installation state. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-128785 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a fluid control valve unit and a valve timing change device using the same that can simplify the structure, reduce the number of parts, improve functional reliability, ensure smooth operation, and obtain desired functions. [Means for solving the problem]

[0007] The fluid control valve unit of the present invention comprises a bottomed cylindrical sleeve defining a predetermined axis, a fluid control valve including a spool housed in the sleeve so as to be slidable in the axial direction, a cylindrical passage member having an inner circumferential surface for fitting the sleeve, a receiving portion for receiving an end of the sleeve in the axial direction, and an annular groove recessed from the inner circumferential surface, and a snap ring having a notch with a predetermined gap fitted into the annular groove to prevent the fluid control valve housed in the passage member from falling off in the axial direction and to enable the fluid flowing through a discharge passage formed in the passage member to be discharged. The passage member includes a positioning recess that positions the sleeve around the axis, the sleeve includes the discharge passage that discharges the fluid and a positioning protrusion that fits into the positioning recess, and the snap ring includes an opening that allows the fluid to pass through and a fitting protrusion that fits into the positioning recess so that the opening corresponds to the discharge passage.

[0009] In the above-described fluid control valve unit, the snap ring may have a configuration including an annular receiving portion that receives the sleeve, and a protruding receiving portion that protrudes radially inward from the annular receiving portion and releasably receives the spool.

[0010] In the above-described fluid control valve unit, the snap ring may have two holes for inserting an installation tool near both ends defining the notch, and the opening may be defined by the notch and the two holes.

[0011] In the above-described fluid control valve unit, the sleeve may have a configuration including a first groove passage and a second groove passage formed in the outer wall and extending in the axial direction to define the discharge passage.

[0012] In the above-described fluid control valve unit, a configuration may be adopted in which the sleeve includes a communication recess in the outer wall that communicates the first groove passage and the second groove passage in the circumferential direction to define the discharge passage.

[0013] The above-described fluid control valve unit may further include a filter member sandwiched between the end of the sleeve and the receiving portion.

[0014] In the above-described fluid control valve unit, the snap ring may be formed in a flat plate shape that expands in a direction perpendicular to the axis.

[0015] In the above-described fluid control valve unit, the sleeve may include an inlet through which the fluid flows, and a first communication port and a second communication port located on either side of the inlet in the axial direction, and the spool may include a rod that reciprocates within the sleeve, a first valve portion provided on the rod for opening and closing a passage between the inlet and the first communication port, a second valve portion provided on the rod for opening and closing a passage between the inlet and the second communication port, and a biasing spring that exerts a biasing force in a direction to bring the first valve portion into contact with the snap ring.

[0016] In the above-described fluid control valve unit, the discharge passage may include a first discharge passage that communicates with the first communication port to discharge the fluid when the first valve portion is closed and that communicates with the second communication port to discharge the fluid when the second valve portion is closed, and a second discharge passage that communicates with a region in which the biasing spring is disposed to discharge the fluid.

[0017] In the above-described fluid control valve unit, a configuration may be adopted in which the spool includes a compression spring arranged between the first valve portion and the second valve portion, the first valve portion includes a first fixed portion having a first land capable of closing the first communication port and a first internal passage formed inside the first land and fixed to the rod, and a first movable portion having a first lid portion for opening and closing the first internal passage and supported movably along the rod, the second valve portion includes a second fixed portion having a second land capable of closing the second communication port and a second internal passage formed inside the second land and fixed to the rod, and a second movable portion having a second lid portion for opening and closing the second internal passage and supported movably along the rod, and the compression spring is arranged to exert a biasing force for closing both the first lid portion and the second lid portion.

[0018] The valve timing change device of the present invention is a valve timing change device that changes the opening and closing timing of an intake valve or an exhaust valve driven by a camshaft, and comprises: a housing rotor that rotates coaxially with the camshaft; a vane rotor that cooperates with the housing rotor to define an advance chamber and a retard chamber and rotates integrally with the camshaft; and the fluid control valve unit, in which the sleeve includes an inlet, a first communication port, and a second communication port, and the spool includes a first valve portion and a second valve portion, to control the supply and discharge of hydraulic oil to the advance chamber and the retard chamber; the inlet of the fluid control valve unit is a supply port through which hydraulic oil is supplied, the first communication port of the fluid control valve unit is a retard port that communicates with the retard chamber, and the second communication port of the fluid control valve unit is an advance port that communicates with the advance chamber.

[0019] The above-described variable valve timing device may include a fastening bolt that fastens the vane rotor to the camshaft, and the fastening bolt may be a passage member of the fluid control valve unit.

[0020] In the above-described valve timing change device, the fluid control valve of the fluid control valve unit may be a torque-driven and hydraulically-driven fluid control valve that can move hydraulic oil back and forth between a retard chamber and an advance chamber in response to a fluctuating torque received by the camshaft and that can discharge a portion of the supplied hydraulic oil.

[0021] In the above-described variable valve timing device, the spool may be configured such that, when positioned in a retard mode in which the first valve section is open and the second valve section is closed, the second valve section opens to allow hydraulic oil to flow from the advance port to the retard port when the camshaft receives torque in a reverse direction, and, when positioned in an advance mode in which the first valve section is closed and the second valve section is open, the first valve section opens to allow hydraulic oil to flow from the retard port to the advance port when the camshaft receives torque in a forward direction.

[0022] In the above-described valve timing change device, the spool may be configured to block the flow of hydraulic oil between the retard chamber and the advance chamber when the spool is positioned in a neutral holding mode in which the first valve portion closes the retard port and the second valve portion closes the advance port. [Effects of the Invention]

[0023] The fluid control valve unit having the above configuration can simplify the structure, reduce the number of parts, improve functional reliability, ensure smooth operation, and obtain the desired function. Also, a variable valve timing device having the fluid control valve unit having the above configuration can smoothly discharge excess hydraulic oil while achieving a compact device, and can obtain the desired operation without causing malfunction of the fluid control valve. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a schematic diagram showing the configuration of an engine to which a variable valve timing device including a fluid control valve according to the present invention is applied; [Figure 2]2 is an exploded perspective view of the electromagnetic actuator, the fastening bolt incorporating the fluid control valve, the variable valve timing device, and the camshaft in the configuration shown in FIG. 1, viewed obliquely from the front on the side opposite to the camshaft. FIG. [Figure 3] 2 is an exploded perspective view of the electromagnetic actuator, the fastening bolt incorporating the fluid control valve, the variable valve timing device, and the camshaft in the configuration shown in FIG. 1, as viewed obliquely from behind the camshaft side. FIG. [Figure 4] 1 is an exploded perspective view of a housing rotor, a vane rotor, a rotational biasing spring, and a camshaft included in a valve timing changing device of the present invention, viewed obliquely from the front opposite the camshaft. FIG. [Figure 5] 1 is an exploded perspective view of a housing rotor, a vane rotor, a rotational biasing spring, and a camshaft included in a valve timing changing device of the present invention, viewed obliquely from behind the camshaft side. FIG. [Figure 6] 1 is a cross-sectional view showing a locked state in which a locking mechanism is activated with the valve timing changing device of the present invention fastened and fixed to a camshaft by a fastening bolt. FIG. [Figure 7] 4 is a cross-sectional view showing a passage in the area around the fluid control valve in a state in which the valve timing changing device of the present invention is fastened and fixed to the camshaft by a fastening bolt. FIG. [Figure 8] 1 is an external perspective view showing a fluid control valve unit according to the present invention; [Figure 9] FIG. 9 is an exploded perspective view of the fluid control valve unit shown in FIG. 8, viewed obliquely from the front on the side opposite to the camshaft on which the valve timing changing device is attached. [Figure 10] FIG. 9 is an exploded perspective view of the fluid control valve unit shown in FIG. 8, as seen from diagonally behind the camshaft side on which the valve timing changing device is attached. [Figure 11] FIG. 2 is an external perspective view showing a snap ring included in the fluid control valve unit of the present invention. [Figure 12] FIG. 2 is an external perspective view showing a sleeve included in the fluid control valve unit of the present invention. [Figure 13]2 is a perspective cross-sectional view showing the fluid control valve unit of the present invention, taken along a plane passing through a first discharge passage (first groove passage). FIG. [Figure 14] 4 is a perspective cross-sectional view showing the fluid control valve unit of the present invention, taken along a plane passing through a second discharge passage (second groove passage). FIG. [Figure 15] 2 is a cross-sectional view of the fluid control valve unit of the present invention in the region of a first discharge passage (first groove passage) that can communicate with a first communication port and a second communication port. FIG. [Figure 16] 1 is a cross-sectional view of a fluid control valve unit according to the present invention, taken along a line AA in FIG. 1, in a region of a second discharge passage communicating with a region where a biasing spring for biasing a spool is disposed. [Figure 17] 1 is a cross-sectional view of a fluid control valve unit according to the present invention in the region of an inlet (supply port). [Figure 18] 1 is a cross-sectional view of a fluid control valve unit according to the present invention, taken in the region of a first communication port (retard port) and a second communication port (advance port). [Figure 19] FIG. 2 is a perspective cross-sectional view showing a spool included in the fluid control valve unit of the present invention. [Figure 20] FIG. 10 is a cross-sectional view showing a state in which the vane rotor is locked in an intermediate position relative to the housing rotor. [Figure 21] FIG. 4 is a cross-sectional view showing a state in which the vane rotor is positioned at a most retarded position relative to the housing rotor. [Figure 22] FIG. 4 is a cross-sectional view showing a state in which the vane rotor is positioned at a most advanced position relative to the housing rotor. [Figure 23] 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives a reverse torque in the retard mode. FIG. [Figure 24] 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives torque in the forward direction in the retard mode. FIG. [Figure 25]FIG. 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives a reverse torque in the advance mode. [Figure 26] FIG. 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives torque in the forward direction in the advance mode. [Figure 27] FIG. 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives a reverse torque in the neutral holding mode. [Figure 28] FIG. 10 is a schematic diagram showing the relationship between the spool of the fluid control valve and the flow of hydraulic oil in the retard port, advance port, retard chamber, and advance chamber when the camshaft receives torque in the normal direction in the neutral holding mode. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, a valve timing change device M equipped with a fluid control valve V according to the present invention is attached to a camshaft 1 of an internal combustion engine and changes the opening and closing timing, i.e., valve timing, of an intake valve or an exhaust valve driven by the camshaft 1.

[0026] The internal combustion engine is equipped with a camshaft 1 that drives the intake valve or exhaust valve to open and close, an oil pan 2 that stores hydraulic oil, a supply passage 3 that supplies the hydraulic oil in the oil pan 2 toward the camshaft 1, an oil pump 4 that is provided midway through the supply passage 3 and sucks in, pressurizes, and discharges the hydraulic oil, a discharge passage 5 that returns the hydraulic oil discharged from the flow control valve V to the oil pan 2, a chain cover 6 that covers the valve timing change device M, and an electromagnetic actuator 7 fixed to the chain cover 6.

[0027] As shown in Figures 1 to 7, the camshaft 1 rotates in one direction CR around an axis S, and is provided with a fitting shaft portion 1a, passages 1b and 1c, a female thread portion 1d, and a fitting hole 1e into which a positioning pin P is fitted. The supply passage 3 is formed in the cylinder block, cylinder head, etc. of the internal combustion engine. The discharge passage 5 is defined between the cylinder block and cylinder head of the internal combustion engine and the chain cover 6, and returns excess hydraulic oil discharged from the flow control valve V to the oil pan 2. The electromagnetic actuator 7 is fixed to the chain cover 6, and as shown in FIG. 3, includes a drive shaft 7a that moves in the direction of the axis S, and an exciting coil (not shown) that drives the drive shaft 7a.

[0028] As shown in FIGS. 2 to 7, the variable valve timing device M includes a housing rotor 10, a vane rotor 20, a rotation biasing spring 30, a locking mechanism 40, and a fluid control valve unit U. The fluid control valve unit U includes a fastening bolt 50 as a passage member, a filter member 60, a fluid control valve V arranged inside the fastening bolt 50, and a snap ring 110. The fluid control valve V controls the flow of hydraulic oil by switching the passage, and includes a sleeve 70, a spool 80, a biasing spring 90, and a check valve 100.

[0029] The housing rotor 10 is rotatably supported on the axis S of the camshaft 1, and is linked to the rotation of the crankshaft via a chain, transmitting the rotational driving force of the crankshaft to the camshaft 1 via the vane rotor 20. 4 to 7, the housing rotor 10 has a two-piece structure consisting of a disk-shaped first housing 11 and a bottomed, cylindrical second housing 12 connected to the first housing 11. The housing rotor 10 accommodates the vane rotor 20 so that the vane rotor 20 can rotate relatively within an angle range between the most retarded position and the most advanced position, and cooperates with the vane rotor 20 to define an advance chamber AC and a retard chamber RC.

[0030] The first housing 11 has a sprocket 11a, a mating hole 11b, an inner wall surface 11c, a locking hole 11d, a recess 11e formed continuous with the locking hole 11d, three circular holes 11f for passing the screw b, and a positioning hole 11g for fitting the positioning pin P2. The fitting hole 11b is rotatably fitted onto the fitting shaft portion 1a of the camshaft 1. The inner wall surface 11c is in slidable contact with the back surface 24 of the vane rotor 20. The lock pin 41 of the lock mechanism 40 is fitted into the lock hole 11d with a small gap. The recess 11e is formed around the lock hole 11d and guides hydraulic oil to the tip pressure-receiving portion 41a of the lock pin 41 fitted into the lock hole 11d.

[0031] As shown in Figures 4 to 7, the second housing 12 has a cylindrical wall 12a, a front wall 12b, an opening 12c, three screw holes 12d for screwing in screws b, three shoe portions 12e, a hooking groove 12f, a recess 12g, an annular joint portion 12h joined to the inner wall surface 11c of the first housing 11, and a positioning hole 12i for fitting the positioning pin P2.

[0032] The opening 12c is a circular hole with the axis S as its center so that the fastening bolt 50 can be passed through. The three shoe portions 12e are formed inside the front wall 12b, protruding from the cylindrical wall 12a toward the center and arranged at equal intervals in the circumferential direction. One shoe portion 12e contacts the vane portion 22 of the vane rotor 20 to define the maximum retard position, and the other shoe portion 12e contacts the vane portion 22 of the vane rotor 20 to define the maximum advance position. The locking groove 12f is formed by cutting out a part of the opening 12c so as to lock the first end 32 of the rotation biasing spring 30. The recess 12g accommodates a part of the coil portion 31 of the rotation biasing spring 30.

[0033] The vane rotor 20 is arranged inside the housing rotor 10 and cooperates with the housing rotor 10 to define the advance chamber AC and the retard chamber RC. The vane rotor 20 is fixed to the camshaft 1 with a fastening bolt 50 sandwiching a washer W therebetween and rotates integrally with the camshaft 1. As shown in Figures 4 to 7, the vane rotor 20 has a hub portion 21, three vane portions 22, a front surface 23, an annular recess 23a, a locking groove 23b, a back surface 24, a fitting hole 25, a recess 26, a groove passage 27, a retard passage 28, and an advance passage 29.

[0034] The vane portion 22 cooperates with the shoe portion 12e of the housing rotor 10 to define an advance chamber AC and a retard chamber RC. The front surface 23 is disposed in slidable contact with the inner wall surface of the front wall 12b of the second housing 12. The annular recess 23a is formed by removing an annular portion of the front surface 23 to accommodate a portion of the coil portion 31 of the rotation biasing spring 30. The retaining groove 23b is formed by removing an annular portion of the front surface 23 to retain the second end portion 33 of the rotation biasing spring 30.

[0035] The back surface 24 is formed in a plane perpendicular to the axis S, is joined to the end face of the camshaft 1, and is disposed in slidable contact with the inner wall surface 11c of the first housing 11. The back surface 24 is also provided with a fitting hole 24a into which a positioning pin P, which is assembled into the fitting hole 1e of the camshaft 1, is fitted. The fitting hole 24a is formed with an inner diameter dimension such that the cylindrical portion 50a of the fastening bolt 50 is fitted closely thereto. As shown in Figures 5 and 6, the recess 26 is formed in one vane portion 22 to accommodate the locking mechanism 40, and is provided with a receiving portion 26a that receives the biasing spring 42 included in the locking mechanism 40, and a communicating passage 26b that communicates with the outside of the vane rotor 20.

[0036] Groove passage 27 is formed by annular groove passage 27a and straight groove passage 27b, and cooperates with the end face of camshaft 1 and inner wall surface 11c of housing rotor 10 to supply hydraulic oil toward and discharge hydraulic oil from lock mechanism 40. That is, groove passage 27 supplies hydraulic oil guided through through passage 54 of fastening bolt 50 to lock mechanism 40 upstream of fluid control valve V in the flow direction of the supplied hydraulic oil to unlock it, and also discharges it when locked. Groove passage 27 is formed on back surface 24 of vane rotor 20, making it easy to process and providing lubrication to the sliding area of ​​inner wall surface 11c.

[0037] The retard passage 28 supplies and discharges hydraulic oil to the retard chamber RC, and as shown in Figure 21, is formed by an annular groove 28a formed on the inner surface of the fitting hole 25 and a through passage 28b that radially penetrates the hub portion 21 from the annular groove 28a. The advance passage 29 supplies and discharges hydraulic oil to the advance chamber AC, and as shown in Figure 22, is formed by an annular groove 29a formed on the inner surface of the fitting hole 25 and a through passage 29b that radially penetrates the hub portion 21 from the annular groove 29a.

[0038] As shown in FIGS. 4 to 6, the rotation biasing spring 30 is a coil spring having a coil portion 31, a first end portion 32, and a second end portion 33. The rotation biasing spring 30 has a coil portion 31 housed in the annular recess 23a of the vane rotor 20 and the recess 12g of the housing rotor 10, a first end 32 hooked to the hook groove 12f of the housing rotor 10, and a second end 33 hooked to the hook groove 23b of the vane rotor 20. As a result, the rotation biasing spring 30 rotationally biases the vane rotor 20 in the advance angle direction relative to the housing rotor 10.

[0039] In this way, by employing the rotational biasing spring 30 that biases in the advance angle direction, the operating torque when advancing the engine can be assisted, thereby improving responsiveness. Also, by setting the load of the rotational biasing spring 30 so that the difference between the operating torque and the load torque is approximately the same during advance and retard, controllability can be improved.

[0040] As shown in Fig. 6, the locking mechanism 40 includes a locking pin 41, a biasing spring 42, and a cylindrical holder 43. As shown in Fig. 20, the locking mechanism 40 locks the vane rotor 20 at an intermediate position between the most retarded position and the most advanced position relative to the housing rotor 10. The lock pin 41 is generally cylindrical and has a tip pressure-receiving portion 41a. The lock pin 41 is held so as to be able to freely protrude and retract in the direction of the axis S relative to the back surface 24 of the vane rotor 20 so as to be able to fit into the lock hole 11d of the housing rotor 10. The biasing spring 42 biases the lock pin 41 in a protruding direction. The cylindrical holder 43 is fitted and fixed in the recess 26 of the vane rotor 20 to hold the lock pin 41, which is biased by the biasing spring 42, so that it can move back and forth. As shown in Figures 5 and 6, the cylindrical holder 43 is disposed so as to recess from the back surface 24 of the vane rotor 20 to define an annular oil reservoir C that communicates with the linear groove passage 27b around the lock pin 41. By providing the annular oil reservoir C, hydraulic oil is filled around the lock pin 41, allowing the lock to be released smoothly.

[0041] When the engine is started, hydraulic oil pressurized by the oil pump 4 is guided to the locking mechanism 40 through the passages 1b and 1c of the camshaft 1, the gap passage Cp in the fastening bolt 50, the through passage 54 of the fastening bolt 50, and the groove passage 27 and annular oil reservoir C formed on the back surface 24 of the vane rotor 20. When the oil pressure applied to the tip pressure-receiving portion 41a of the locking pin 41 increases, the locking pin 41 disengages from the locking hole 11d and the lock is released. On the other hand, when the engine is stopped and the oil pressure of the supplied hydraulic oil drops, the hydraulic oil acting on the lock pin 41 flows out through the groove passage 27, the through passage 54, the gap passage Cp, and the passages 1c and 1b, reducing the oil pressure pressing the lock pin 41. Then, the lock pin 41 is urged by the urging spring 42 to fit into the lock hole 11d of the housing rotor 10, and the vane rotor 20 is locked in the intermediate position relative to the housing rotor 10.

[0042] As shown in Figures 2, 3, and 6 to 10, the fastening bolt 50 includes a cylindrical portion 50a centered on the axis S, an inner circumferential surface 51 for fitting the fluid control valve V, an opening 52, an annular receiving portion 53, a through passage 54, a retard passage 55, an advance passage 56, a flanged head portion 57, a male thread portion 58, a positioning recess 59a, and an annular groove portion 59b.

[0043] Cylindrical portion 50a is formed with an outer diameter dimension that allows it to fit closely into fitting hole 25 of vane rotor 20. Inner circumferential surface 51 forms a cylindrical surface centered on axis S. Opening 52 is formed as a circular hole with a smaller diameter than inner circumferential surface 51 and functions as a passage for passing hydraulic oil. The receiving portion 53 is formed in an annular shape inside the opening 52 and receives the end portion 70a of the sleeve 70 via the filter member 60 in the direction of the axis S. In this way, the fastening bolt 50 has a receiving portion 53 integrally formed to receive the fluid control valve V (end 70a of the sleeve 70). Therefore, by simply fitting the snap ring 110 on the opposite side, it is possible to prevent the fluid control valve V from moving in the direction of the axis S and falling off with a simple structure. The through passage 54 is for introducing or discharging hydraulic oil to or from the locking mechanism 40, and penetrates the cylindrical portion 50a in a radial direction perpendicular to the axis S. The retard passage 55 penetrates the cylindrical portion 50a in a radial direction perpendicular to the axis S so as to communicate with the retard passage 28 of the vane rotor 20. The advance passage 56 penetrates the cylindrical portion 50 a in a radial direction perpendicular to the axis S so as to communicate with the advance passage 29 of the vane rotor 20 . The flanged head 57 abuts against the front surface 23 of the vane rotor 20 with a washer W sandwiched therebetween. The male thread portion 58 is screwed into the female thread portion 1d of the camshaft 1. The positioning recess 59a is formed so that the positioning protrusion 79 of the sleeve 70 included in the flow control valve V and the fitting protrusion 114 of the snap ring 110 can be fitted therein. The annular groove portion 59b is formed adjacent to the inner circumferential surface 51 and recessed from the inner circumferential surface 51 so that a snap ring 110 can be fitted therein.

[0044] The filter member 60 captures foreign matter mixed into the hydraulic oil supplied by the oil pump 4, and is sandwiched between the receiving portion 53 and the end of the sleeve 70 inside the fastening bolt 50.

[0045] The fluid control valve V switches the passages to supply or discharge hydraulic oil to the advance chamber AC and the retard chamber RC, and as shown in Figures 9, 10, 12 to 14, it is equipped with a sleeve 70, a spool 80, a biasing spring 90, and a check valve 100.

[0046] As shown in Figures 9, 10, 12 to 18, the sleeve 70 is formed into a cylindrical shape with a bottom using aluminum or other metal material, and is provided with an end portion 70a, an outer wall 71, lightening portions 71a, 71b, 71c, a first groove passage 71d and through passages 71d1, 71d2 as a first discharge passage that forms part of the discharge passage, a second groove passage 71e and through passage 71e1 as a second discharge passage that forms part of the discharge passage, a fitting hole 71f, a fitting pin 71g, a communicating recess 71h that forms part of the discharge passage, an inner circumferential surface 72, annular groove portions 72a, 72b, 72c, an opening 73, a supply port 74, a retard port 75, an advance port 76, a stopper wall 77, a spring bearing portion 78, and a positioning protrusion 79.

[0047] 10, 13 and 14, the end portion 70a is received by the receiving portion 53 of the fastening bolt 50 with the filter member 60 sandwiched therebetween in the direction of the axis S. The outer wall 71 is formed as a cylindrical surface centered on the axis S, and is fitted closely to the inner peripheral surface 51 of the fastening bolt 50 . The hollowed-out portion 71a is formed by hollowing out a portion of the outer wall 71 in the area facing the supply port 74 (first supply port 74a and second supply port 74b) from the outside of the bottom wall, and cooperates with the inner wall of the fastening bolt 50 to define the gap passage Cp. The recessed portion 71 b is formed by removing part of the outer wall 71 in the region facing the retard port 75 toward the retard passage 55 of the fastening bolt 50 , and functions as a passage between the retard port 75 and the retard passage 55 . The recessed portion 71c is formed by removing part of the outer wall 71 in the region facing the advance port 76 toward the advance passage 56 of the fastening bolt 50, and functions as a passage between the advance port 76 and the advance passage 56.

[0048] The groove passage 71d is formed in the outer wall 71 and extends in the direction of the axis S. In cooperation with the through passage 71d1, the groove passage 71d functions as a first discharge passage that communicates with the retard port 75 as a first communication port when the first valve portion 82 is closed to discharge the hydraulic oil, and in cooperation with the through passage 71d2 functions as a first discharge passage that communicates with the advance port 76 as a second communication port when the second valve portion 83 is closed to discharge the hydraulic oil. The groove passage 71e is formed extending in the direction of the axis S in the outer wall 71 at a position away from the groove passage 71d, and in cooperation with the through passage 71e1, functions as a second discharge passage that can discharge hydraulic oil accumulated in the area where the biasing spring 90 is located and also serves as a breathing passage.

[0049] The fitting hole 71f is for fitting the fitting pin 71g, and is formed as a two-step hole that penetrates the bottom wall of the annular groove portion 72a in the radial direction. The mating pin 71g is a stepped pin made of iron or steel material, etc., consisting of two integrally formed cylinders with different outer diameters. It fits tightly into the mating hole 71f and protrudes radially inward from the bottom surface of the annular groove portion 72a so as not to interfere with the spool 80. The communication recess 71h is formed in the outer wall 71 near the opening 73 so as to connect the first groove passage 71d and the second groove passage 71e in the circumferential direction.

[0050] The inner peripheral surface 72 is formed in a cylindrical shape centered on the axis S, and guides the first valve portion 82 (first land 82a1) and the second valve portion 83 (second land 83a1) of the spool 80 in close contact with each other so that they can slide freely. The annular groove portion 72a is formed as a cylindrical surface by hollowing out the annular shape so that it is wider than the opening width of the supply port 74 in the direction of the axis S in the area facing the supply port 74 as an inlet and recessed from the inner surface 72, and a check valve 100 is arranged inside it. The annular groove portion 72b is formed by recessing the inner circumferential surface 72 in an area facing the retard port 75 serving as the first communication port, and functions as a passage for hydraulic oil. The annular groove portion 72c is formed by recessing an annular portion from the inner circumferential surface 72 in a region facing the advance port 76 serving as a second communication port, and functions as a passage for hydraulic oil.

[0051] The opening 73 allows the rod 81 of the spool 80 to protrude in the direction of the axis S. The supply port 74 functions as an inlet through which hydraulic oil flows as a fluid, and is in communication with the clearance passage Cp and is disposed downstream of the through passage 54 in the clearance passage Cp. 10, the supply port 74 includes a first supply port 74a serving as a first inlet and a second supply port 74b serving as a second inlet, which are spaced apart from each other around the axis S.

[0052] The retard port 75 functions as a first communication port that communicates with the outside to allow hydraulic oil to pass through as a fluid, and is connected to the retard passage 55 of the fastening bolt 50 via the hollowed-out portion 71b, and is also connected to the retard chamber RC via the retard passage 28 of the vane rotor 20. The advance port 76 functions as a second communication port that communicates with the outside to allow hydraulic oil to pass through as a fluid, and is connected to the advance passage 56 of the fastening bolt 50 via the lightening portion 71c, and is also connected to the advance chamber AC via the advance passage 29 of the vane rotor 20. 17 and 18, the retarded angle port 75 and the advanced angle port 76 are disposed so as to be located on both sides of the supply port 74 in the direction of the axis S. In other words, the communication ports that communicate with the outside to pass a fluid include a first communication port (retarded angle port 75) and a second communication port (advance angle port 76) that are located on both sides of the inlet (supply port 74) in the direction of the axis S. The stopper wall 77 receives an end face 83a2 of the second valve portion 83 of the spool 80, and stops the spool 80 at the innermost position corresponding to the advance mode. The spring seat 78 receives the end of a biasing spring 90 . When the sleeve 70 is fitted onto the inner peripheral surface 51 of the fastening bolt 50, the positioning protrusion 79 is fitted into the positioning recess 59a of the fastening bolt 50 to position the sleeve 70 at a predetermined position around the axis S relative to the fastening bolt 50.

[0053] As described above, the sleeve 70 has discharge passages (first groove passage 71d, second groove passage 71e, and communicating recess 71h) formed in the outer wall 71 for passing the hydraulic oil to be discharged to the outside, so there is no need to provide a discharge passage in the fastening bolt 50 serving as a passage member. Therefore, the fluid control valve V including the sleeve 70 can be applied to various existing passage members.

[0054] As shown in Figures 13 to 19, the spool 80 is arranged inside the sleeve 70 so as to be able to slide freely on the inner surface 72, and is equipped with a rod 81 extending in the direction of the axis S, a first valve portion 82 and a second valve portion 83 provided on the rod 81, and a compression spring 84 arranged between the first valve portion 82 and the second valve portion 83. The rod 81 is formed to extend in the direction of the axis S and has an end portion 81a exposed to the outside. The drive shaft 7a of the electromagnetic actuator 7 engages with the end portion 81a, and a driving force is exerted against the biasing force of the biasing spring 90.

[0055] The first valve portion 82 opens and closes the passage between the supply port 74 and the retard port 75, and includes a first fixed portion 82a fixed to the rod 81, and a first movable portion 82b movably supported along the rod 81 and biased by a compression spring 84. The first fixing portion 82a includes a first land 82a1 that slides in close contact with the inner circumferential surface 72, an end surface 82a2, a first internal passage 82a3, and an end surface 82a4. The first land 82a1 is a cylindrical surface centered on the axis S, with an outer diameter approximately the same as or slightly smaller than the inner diameter of the inner circumferential surface 72, and is formed with a width dimension that closes the retard port 75, thereby opening or closing the retard port 75. The first movable part 82b functions as a check valve in cooperation with the compression spring 84, and includes a first fitting part 82b1 slidably fitted to the rod 81, and a first lid part 82b2 that detachably abuts against the end face 82a4 to open and close the first internal passage 82a3.

[0056] The second valve portion 83 opens and closes the passage between the supply port 74 and the advance port 76, and includes a second fixed portion 83a fixed to the rod 81, and a second movable portion 83b movably supported along the rod 81 and biased by a compression spring 84. The second fixing portion 83a includes a second land 83a1 that slides in close contact with the inner circumferential surface 72, an end surface 83a2, a second internal passage 83a3, and an end surface 83a4. The second land 83a1 is a cylindrical surface centered on the axis S, with an outer diameter that is approximately the same as or slightly smaller than the inner diameter of the inner circumferential surface 72, and is formed with a width dimension that closes the advance port 76, thereby opening or closing the advance port 76. The second movable part 83b functions as a check valve in cooperation with the compression spring 84, and is provided with a second fitting part 83b1 slidably fitted to the rod 81, and a second lid part 83b2 that detachably abuts against the end face 83a4 to open and close the second internal passage 83a3.

[0057] The compression spring 84 is a compression type coil spring that is arranged between the first movable part 82b of the first valve part 82 and the second movable part 83b of the second valve part 83, and exerts a biasing force so that the first cover part 82b2 closes the first internal passage 82a3 and the second cover part 83b2 closes the second internal passage 83a3.

[0058] Here, the relationship between the biasing force of the compression spring 84 and the passage resistance of the through passage 71d1 forming a part of the first discharge passage and the through passage 71d2 forming a part of the second discharge passage will be described. When the first valve portion 82 is in a closed state and the pressure of the hydraulic oil flowing in from the retard port 75 is high, the first lid portion 82b2 opens, and little hydraulic oil is discharged from the first discharge passage (through passage 71d1), and the hydraulic oil actively flows into the advance port 76 side; on the other hand, when the pressure of the hydraulic oil flowing in from the retard port 75 is low, the first lid portion 82b2 closes and the hydraulic oil is actively discharged from the first discharge passage (through passage 71d1). Furthermore, when the second valve portion 83 is in a closed state and the pressure of the hydraulic oil flowing in from the advance port 76 is high, the second lid portion 83b2 opens, so that little hydraulic oil is discharged from the first discharge passage (through passage 71d2), and the hydraulic oil actively flows into the retard port 75 side; on the other hand, when the pressure of the hydraulic oil flowing in from the advance port 76 is low, the second lid portion 83b3 closes, so that the hydraulic oil is actively discharged from the first discharge passage (through passage 71d2). The biasing force of the compression spring 84 and the passage resistance of the through passages 71d1 and 71d2 are set so as to perform the above operation.

[0059] 13 to 18, the biasing spring 90 is a compression type coil spring, and is assembled so that one end abuts against the end face 83a2 of the spool 80 and the other end abuts against the spring receiving portion 78 of the sleeve 70. When the biasing spring 90 is in a resting state, it exerts a biasing force that stops the spool 80 at a rest position where the end face 82a2 of the spool 80 abuts against the protruding receiving portions 112, 113 of the snap ring 110, i.e., at a position corresponding to the retard mode.

[0060] The check valve 100 is a C-shaped leaf spring made of spring steel that is bent into a circular ring shape with both ends facing each other, forming a notch with a predetermined gap, and is pre-curved to have an outer diameter larger than the inner diameter of the annular groove portion 72a. The check valve 100 is arranged in the annular groove portion 72a of the sleeve 70 so that the mating pin 71g is positioned in the gap of the notch portion and can be contracted in diameter, and functions as a check valve that only allows the flow of hydraulic oil supplied to the interior through the supply port 74 of the sleeve 70.

[0061] The check valve 100 has an opening characteristic set so that the hydraulic oil flows into the fluid control valve V through the passages 1b, 1c, the clearance passage Cp, and the supply port 74, and is then supplied from the retard port 75 to the retard chamber RC or from the advance port 76 to the advance chamber AC. After that, the hydraulic oil filling the through passage 54 and the groove passage 27 reaches a hydraulic pressure sufficient to release the lock mechanism 40, and the lock is released.

[0062] The snap ring 110 is fitted into the annular groove portion 59b of the fastening bolt 50 and is made of spring steel or the like. As shown in FIG. 11, the snap ring 110 is formed in a generally C-shape, having a flat plate shape extending in a direction perpendicular to the axis S and a notch portion 110a with a predetermined gap. The snap ring 110 includes an annular receiving portion 111, a plurality of (here, five) protruding receiving portions 112, 113 that protrude radially inward from the annular receiving portion 111 at approximately equal intervals around the axis S, and a fitting protrusion 114.

[0063] The annular receiving portion 111 receives the end face of the sleeve 70 on the opening 73 side when the sleeve 70 is inserted into the inner circumferential surface 51 of the fastening bolt 50 . The two protruding receiving portions 112 and the three protruding receiving portions 113 each receive the end face of the sleeve 70 in a root side region and detachably receive the end face 82a of the spool 80 in a tip side region. The two protruding receiving portions 112 are provided near both end portions 111a, 111b that define the notch portion 110a, and have two holes, that is, a circular hole 112a on one side and a circular hole 112b on the other side. The two circular holes 112a and 112b are for inserting the tip of a tool (for example, snap ring pliers) used when attaching the snap ring 110 to the annular groove portion 59b.

[0064] In the snap ring 110 having the above-described configuration, the notch 110a and the two circular holes 112a, 112b function as openings through which hydraulic oil passes. The mating protrusion 114 is formed to be mated with the positioning recess 59a of the fastening bolt 50 so that the opening (the notch 110a and the two circular holes 112a, 112b) corresponds to the discharge passage (the first groove passage 71d, the second groove passage 71e, and the communicating recess 71h) at an angular position around the axis S.

[0065] That is, as shown in Figures 10, 13 and 14, the snap ring 110 is fitted into the annular groove portion 59b after the fluid control valve V (sleeve 70, spool 80, biasing spring 90, check valve 100) and the filter member 60 are fitted into the fastening bolt 50, thereby preventing the fluid control valve V housed in the fastening bolt 50 from falling off in the direction of the axis S and enabling the hydraulic oil flowing through the discharge passages (first groove passage 71d, second groove passage 71e, communicating recess 71h) formed in the fastening bolt 50 to be discharged. As a result, when the fluid control valve unit U is applied to the valve timing change device M to change the valve timing, excess hydraulic oil can be discharged smoothly without remaining, thereby achieving the desired change operation.

[0066] According to the fluid control valve unit U having the above configuration, the fastening bolt 50 as a passage member has a receiving portion 53 that receives the end portion 70a of the sleeve 70 in the direction of the axis S and an annular groove portion 59b that is recessed further than the inner circumferential surface 51, and the snap ring 110 is fitted into the annular groove portion 59b to prevent the fluid control valve V housed in the fastening bolt 50 from falling off in the direction of the axis S and to discharge the hydraulic oil flowing through the discharge passages (the first groove passage 71d as the first discharge passage and the second groove passage 71e as the second discharge passage) formed in the fastening bolt 50, thereby making it possible to simplify the structure and reduce the number of parts, thereby improving functional reliability.

[0067] Furthermore, the fastening bolt 50 includes a positioning recess 59a that positions the sleeve 70 around the axis S, the sleeve 70 includes discharge passages (a first groove passage 71d as the first discharge passage and a second groove passage 71e as the second discharge passage) and a positioning protrusion 79 that fits into the positioning recess 59a, and the snap ring 110 includes openings (cutout portion 110a and two circular holes 112a, 112b) through which the hydraulic oil passes and a fitting protrusion 114 that fits into the positioning recess 59a to make the openings (110a, 112a, 112b) correspond to the discharge passages (71d, 71e, 71h). Therefore, simply by fitting the fitting protrusion 114 into the positioning recess 59a and assembling it, the openings (110a, 112a, 112b) can be easily positioned so that they correspond to the discharge passages (71d, 71e, 71h).

[0068] Furthermore, since the sleeve 70 has discharge passages (first groove passage 71d, second groove passage 71e, communicating recess 71h) in the outer wall 71 through which the hydraulic oil passes to be discharged to the outside, there is no need to provide a discharge passage in the fastening bolt 50 serving as a passage member, and therefore the fluid control valve V including the sleeve 70 can be applied to various existing passage members. Furthermore, the sleeve 70 includes a communicating recess 71h in the outer wall 71 that connects the first groove passage 71d and the second groove passage 71e in the circumferential direction to define a discharge passage, so that the hydraulic oil can be easily guided toward the opening (notch portion 110a) of the snap ring 110.

[0069] Furthermore, since the filter member 60 is sandwiched between the end 70a of the sleeve 70 and the receiving portion 53 of the fastening bolt 50, installation is simpler than in the conventional case where the filter member 60 is fixed by fitting it onto the inner surface of the passage member, and functional reliability is improved. Furthermore, since the snap ring 110 is formed in a flat plate shape that expands in a direction perpendicular to the axis S, it can be made thinner in the direction of the axis S compared to a cylindrical shape with a bottom, which contributes to the miniaturization of the fluid control valve unit U.

[0070] Furthermore, the snap ring 110 is inserted into the annular groove portion 59b while reducing its diameter using a tool, and then simply by removing the tool, the diameter expands, making it closely contact with the bottom surface of the annular groove portion 59b and restricting movement in the direction of the axis S. This simplifies installation and prevents it from coming off the annular groove portion 59b even when subjected to impacts caused by the reciprocating movement of the spool 80. Therefore, compared to conventional engaging members that are fixed by fitting to the inner surface, the structure can be simplified and functional reliability can be improved, ensuring smooth operation and desired functionality of the fluid control valve V. Although five protruding receiving portions 112 and 113 are shown here, at least one protruding receiving portion, preferably three protruding receiving portions arranged at equal intervals, may be employed.

[0071] Next, the operation of the valve timing varying device M will be described. When the internal combustion engine is stopped, the vane rotor 20 is locked in an intermediate position relative to the housing rotor 10 by the locking mechanism 40, as shown in FIG. This allows the internal combustion engine to be started smoothly while preventing flapping of the vane rotor 20. Furthermore, when the internal combustion engine is stopped, the retard chamber RC is basically filled with hydraulic oil, except for the oil that leaks from gaps, etc., due to the opening of the first valve portion 82 at the rest position (a state in which communication between the first groove passage 71d and the through passage 71d1 and the retard port 75 is blocked) and the backflow prevention function of the check valve 100.

[0072] Next, when the internal combustion engine starts, the hydraulic oil supplied through the passages 1b, 1c and the clearance passage Cp opens the check valve 100 and flows into the fluid control valve V from the supply port 74, and is supplied from the retard port 75 to the retard chamber RC or from the advance port 76 to the advance chamber AC, and then when the hydraulic oil introduced to the lock mechanism 40 through the through passage 54 and the groove passage 27 reaches a releasable hydraulic pressure, the lock pin 41 disengages from the lock hole 11d and the lock is released. Then, after the internal combustion engine starts, the position of the spool 80 of the fluid control valve V is appropriately controlled via the drive shaft 7a of the electromagnetic actuator 7, and phase control is performed so that the vane rotor 20 and the camshaft 1 are retarded or advanced or are maintained at a predetermined angular position.

[0073] First, we will explain the operation when the internal combustion engine is operating at low speed, for example. In this low speed operating state, the hydraulic oil in the retard chamber RC and the advance chamber AC can move back and forth in response to torque fluctuations (ΔT, -ΔT) exerted by the camshaft 1. For example, in the retard mode, the spool 80 is positioned in a rest position by the biasing force of the biasing spring 90, as shown in FIGS. In the retard mode, the first valve element 82 is set to an open state in which the passage between the supply port 74 and the retard port 75 is open, and the second valve element 83 is set to a closed state in which the passage between the supply port 74 and the advance port 76 is closed, specifically, the second land 83a1 of the second fixed portion 83a opens the advance port 76, and the second lid portion 83b2 of the second movable portion 83b closes the second internal passage 83a3. In addition, the first discharge passage (first groove passage 71d and through passage 71d2) is in a state in which the hydraulic oil in the advance chamber AC can be discharged by communicating with the advance port 76.

[0074] In this state, when the camshaft 1 receives torque (-ΔT) in the opposite direction to the forward rotation direction CR, the hydraulic pressure of the hydraulic oil in the advance chamber AC increases. Therefore, as shown in FIG. 23, the hydraulic oil in the advance chamber AC disengages the second cover portion 83b2 of the second movable portion 83b from the second fixed portion 83a while resisting the biasing force of the compression spring 84. This opens the second internal passage 83a3, and hydraulic oil actively flows from the advance port 76 to the retard port 75. At this time, a smaller amount of hydraulic oil than the hydraulic oil flowing toward the retard port 75 passes through the first discharge passage (the through passage 71d2, the first groove passage 71d, and the communicating recess 71h) and is discharged from the opening (the notch 110a and the circular hole 112a) of the snap ring 110. In addition, hydraulic oil that leaks into the area where the biasing spring 90 is arranged passes through the second discharge passage (through passage 71e1 and second groove passage 71e, communicating recess 71h) and is discharged from the opening of the snap ring 110 (cutout portion 110a, circular hole 112b) as appropriate.

[0075] On the other hand, when the camshaft 1 receives a forward torque (ΔT), the oil pressure of the hydraulic oil in the retard chamber RC increases. However, as shown in Figure 24, the hydraulic oil in the retard chamber RC acts in a direction that causes the second movable portion 83b to abut against the second fixed portion 83a, so the second internal passage 83a3 is closed and no hydraulic oil flows from the retard port 75 to the advance port 76.

[0076] By receiving the reverse torque (-ΔT) and the forward torque (ΔT) successively, the hydraulic oil in the advance chamber AC moves into the retard chamber RC, and the vane rotor 20 is positioned at the most retarded position shown in Fig. 21. During this process, the check valve 100 opens as needed to allow hydraulic oil to flow in from the supply port 74 in order to replenish the hydraulic oil.

[0077] Next, in the advance mode, the spool 80 is positioned at the innermost position in the direction of the axis S by the drive shaft 7a of the electromagnetic actuator 7 against the biasing force of the biasing spring 90, as shown in FIGS. In the advance mode, the second valve element 83 is set to an open state in which the passage between the supply port 74 and the advance port 76 is open, and the first valve element 82 is set to a closed state in which the passage between the supply port 74 and the retard port 75 is closed, specifically, the first land 82a1 of the first fixed element 82a opens the retard port 75, and the first lid element 82b2 of the first movable element 82b closes the first internal passage 82a3. In addition, the first discharge passage (groove passage 71d and through passage 71d1) is in a state in which the hydraulic oil in the retard chamber RC can be discharged by communicating with the retard port 75.

[0078] In this state, when the camshaft 1 receives torque (-ΔT) in the opposite direction to the forward rotation direction CR, the oil pressure of the hydraulic oil in the advance chamber AC increases. However, as shown in Figure 25, the hydraulic oil in the advance chamber AC acts in a direction that causes the first movable portion 82b to abut against the first fixed portion 82a, so the first internal passage 82a3 is closed and no hydraulic oil flows from the advance port 76 to the retard port 75.

[0079] On the other hand, when the camshaft 1 receives a forward torque (ΔT), the hydraulic pressure of the hydraulic oil in the retard chamber RC increases. Therefore, as shown in FIG. 26, the hydraulic oil in the retard chamber RC disengages the first cover portion 82b2 of the first movable portion 82b from the first fixed portion 82a while resisting the biasing force of the compression spring 84. This opens the first internal passage 82a3, and hydraulic oil actively flows from the retard port 75 to the advance port 76. At this time, a smaller amount of hydraulic oil than the hydraulic oil flowing toward the advance port 76 passes through the first discharge passage (the through passage 71d1, the first groove passage 71d, and the communicating recess 71h) and is discharged from the opening of the snap ring 110 (the notch portion 110a and the circular hole 112a). In addition, hydraulic oil that leaks into the area where the biasing spring 90 is arranged passes through the second discharge passage (through passage 71e1 and second groove passage 71e, communicating recess 71h) and is discharged from the opening of the snap ring 110 (cutout portion 110a, circular hole 112b) as appropriate.

[0080] By receiving the reverse torque (-ΔT) and the forward torque (ΔT) successively, the hydraulic oil in the retard chamber RC moves into the advance chamber AC, and the vane rotor 20 is positioned at the most advanced position shown in Fig. 22. During this process, the check valve 100 opens as needed to allow hydraulic oil to flow in from the supply port 74 in order to replenish the hydraulic oil.

[0081] That is, when the spool 80 of the fluid control valve V is positioned in a retard mode in which the first valve section 82 is open and the second valve section 83 is closed, the second valve section 83 opens to allow hydraulic oil to flow from the advance port 76 to the retard port 75 when the camshaft 1 receives a reverse torque (-ΔT), and when the spool 80 is positioned in an advance mode in which the first valve section 82 is closed and the second valve section 83 is open, the first valve section 82 opens to allow hydraulic oil to flow from the retard port 75 to the advance port 76 when the camshaft 1 receives a forward torque (ΔT).

[0082] The above series of operations are performed when the internal combustion engine is in, for example, a low-speed operating state. However, when the internal combustion engine is in, for example, a high-speed operating state, the torque fluctuations (ΔT, -ΔT) exerted by the camshaft 1 are small, and no reciprocating movement of hydraulic oil occurs in the retard chamber RC and the advance chamber AC, making it difficult for the first valve section 82 and the second valve section 83 to open and close due to torque fluctuations. As a result, when the check valve 100 opens, the hydraulic oil supplied from the supply port 74 actively flows into the retard chamber RC or the advance chamber AC, while the hydraulic oil in the advance chamber AC or the retard chamber RC passes through the first discharge passage (the through passage 71d2 or the through passage 71d1 and the first groove passage 71d) and is actively discharged to the outside from the opening (the notch 110a and the circular hole 112a) of the snap ring 110. In addition, the hydraulic oil leaking into the region where the biasing spring 90 is disposed passes through the second discharge passage (the through passage 71e1 and the second groove passage 71e and the communicating recess 71h) and is discharged from the opening (the notch 110a and the circular hole 112b) of the snap ring 110 as appropriate.

[0083] Next, in the neutral holding mode, the spool 80 is positioned at a middle position in the direction of the axis S by the drive shaft 7a of the electromagnetic actuator 7 against the biasing force of the biasing spring 90, as shown in FIGS. In the neutral hold mode, the first valve section 82 is set to a closed state in which the passage between the supply port 74 and the retard port 75 is blocked, and the second valve section 83 is set to a closed state in which the passage between the supply port 74 and the advance port 76 is blocked. Specifically, the first valve portion 82 is set to a state in which the first land 82a1 of the first fixed portion 82a closes the retard port 75, and the first lid portion 81b2 of the first movable portion 82b closes the first internal passage 82a3. The second valve portion 83 is set to a state in which the second land 83a1 of the second fixed portion 83a closes the advance port 76, and the second lid portion 83b2 of the second movable portion 83b closes the second internal passage 83a3. Communication between the first exhaust passage (groove passage 71d and through passage 71d1) and the retard port 75 is blocked, and communication between the second exhaust passage (groove passage 71d and through passage 71d2) and the advance port 76 is blocked.

[0084] In this state, when the camshaft 1 receives torque (-ΔT) in the opposite direction to the forward rotation direction CR, the oil pressure of the hydraulic oil in the advance chamber AC increases. However, as shown in Figure 27, because the advance port 76 is blocked by the second land 83a1 of the second valve portion 83, the hydraulic oil in the advance chamber AC cannot move from the advance port 76 to the retard port 75 and remains in the advance chamber AC.

[0085] On the other hand, when the camshaft 1 receives a forward torque (ΔT), the oil pressure of the hydraulic oil in the retard angle chamber RC increases. However, as shown in Figure 28, the retard angle port 75 is blocked by the first land 82a1 of the first valve portion 82, so the hydraulic oil in the retard angle chamber RC cannot move from the retard angle port 75 to the advance angle port 76 and remains in the retard angle chamber RC.

[0086] As described above, in the neutral holding mode, the flow of hydraulic oil between the retarded angle chamber RC and the advanced angle chamber AC is blocked and the first discharge passage (through passages 71d1, 71d2) is also blocked, so that the vane rotor 20 is held at a desired intermediate position between the most retarded angle position and the most advanced angle position relative to the housing rotor 10. That is, in the fluid control valve V, the spool 80 is configured to block the flow of hydraulic oil back and forth between the retard chamber RC and the advance chamber AC when the spool 80 is positioned in a neutral holding mode in which the first valve section 82 blocks the retard port 75 and the second valve section 83 blocks the advance port 76.

[0087] As described above, the fluid control valve V is a torque-driven and hydraulically-driven fluid control valve that can move hydraulic oil back and forth between the retard chamber RC and the advance chamber AC due to the fluctuating torque received by the camshaft 1 and can also discharge a portion of the supplied hydraulic oil.Therefore, in an operating condition where sufficient fluctuating torque is obtained (for example, during low-speed operation), the hydraulic oil is moved back and forth between the retard chamber RC and the advance chamber AC, and in an operating condition where sufficient fluctuating torque is difficult to obtain (for example, during high-speed operation), the hydraulic oil is actively discharged, making it possible to change the opening and closing timing of the valve to the desired timing.

[0088] As described above, the fluid control valve unit U according to the above embodiment can simplify the structure, reduce the number of parts, improve functional reliability, ensure smooth operation, and obtain the desired functions. Furthermore, the variable valve timing device M equipped with the fluid control valve unit U can smoothly discharge excess hydraulic oil while achieving a compact device, and can obtain the desired operation without causing malfunction of the fluid control valve V.

[0089] In the above embodiment, snap ring 110 having five protruding receiving portions 112, 113 is shown as the snap ring, but this is not limited to this, and snap rings having one, three, or any other number of protruding receiving portions may also be used. In the above embodiment, snap ring 110 is shown as a flat plate-like snap ring that expands in a direction perpendicular to axis S, but this is not limited to this, and snap rings of other shapes may be used as long as they are fitted into the annular groove of the passage member so as to prevent the fluid control valve V housed in the passage member from falling off in the direction of axis S and to be able to discharge the fluid flowing through the discharge passage formed in the passage member.

[0090] In the above embodiment, the lock mechanism 40 is locked at the intermediate position, but this is not limiting and the lock mechanism 40 may be locked at the most retarded position or at another position. In the above embodiment, the rotational biasing spring 30 that exerts a biasing force in the advance angle direction is shown as the rotational biasing spring that rotationally biases the vane rotor 20. However, this is not limited to this, and a rotational biasing spring that exerts a biasing force in the retard angle direction may also be used.

[0091] In the above embodiment, the torque-driven and hydraulically-driven fluid control valves V are shown as the fluid control valves, but this is not limited to this, and other types of fluid control valves may be adopted as long as they supply and discharge hydraulic oil. In the above embodiment, the fluid control valve unit U is shown as a fluid control valve unit in which the fluid control valve V is arranged inside the fastening bolt 50 as a passage member, but the present invention is not limited to this, and can also be applied to a configuration in which the fluid control valve V is arranged in another passage member or in the cylinder block of an engine. In the above embodiment, the fluid controlled by the fluid control valve unit is hydraulic oil, but this is not limited to this and the fluid may be applied to control the flow of other fluids.

[0092] As described above, the fluid control valve unit of the present invention can simplify the structure, reduce the number of parts, improve functional reliability, ensure smooth operation, and obtain desired functions. Therefore, it is not only applicable to internal combustion engines mounted on automobiles, but is also useful in internal combustion engines mounted on motorcycles, etc., and other equipment or devices that control the flow of fluids. [Explanation of symbols]

[0093] 1 camshaft M Valve timing change device AC advance chamber RC retardation chamber S axis 10 Housing rotor 20 vane rotor U Fluid Control Valve Unit 50 Fastening bolts (passage components, fluid control valve units) 51 Inner surface 53 Receiving part 59a Positioning recess 59b Annular groove V Fluid control valve (fluid control valve unit) 60 Filter member (fluid control valve unit) 70 Sleeve (fluid control valve) 70a end 71 Exterior Wall 71d 1st groove passage (1st discharge passage, discharge passage) 71d1, 71d2 penetration passage (1st discharge passage) 71e 2nd groove passage (2nd discharge passage, discharge passage) 71e1 penetration passage (second discharge passage) 71h Communication recess (first discharge passage, second discharge passage, discharge passage) 74 Supply port (inlet) 75 Retard port (first communication port) 76 Advance port (second communication port) 79 Positioning protrusion 80 Spool (fluid control valve) 81 Rod 81a End 82 First valve section 82a 1st fixed part 82a1 Land 1 82a3 1st internal passage 82b 1st moving part 82b2 1st lid part 83 Second valve section 83a 2nd fixed part 83a1 2nd Land 83a3 2nd internal passage 83b 2nd moving part 83b2 2nd lid part 84 Compression spring 90 Spring (fluid control valve) 100 Check valve (fluid control valve) 110 Snap ring (fluid control valve unit) 110a Notch (opening) 111 Annular receiving part 112,113 Projection receiving part 112a, 112b circular holes (two holes, openings) 114 mating protrusion

Claims

1. a fluid control valve including a cylindrical sleeve with a bottom defining a predetermined axis, and a spool accommodated in the sleeve so as to be slidable in the axial direction; a cylindrical passage member having an inner circumferential surface into which the sleeve is fitted, a receiving portion that receives an end of the sleeve in the axial direction, and an annular groove that is recessed from the inner circumferential surface; a snap ring having a notch with a predetermined gap fitted into the annular groove so as to prevent the fluid control valve housed in the passage member from falling off in the axial direction and to discharge fluid flowing through a discharge passage formed in the passage member, the passage member includes a positioning recess that positions the sleeve around the axis, the sleeve includes the discharge passage for discharging fluid and a positioning protrusion that is fitted into the positioning recess, The snap ring includes an opening through which a fluid passes, and a fitting protrusion that fits into the positioning recess so as to correspond to the opening and the discharge passage. A fluid control valve unit characterized by:

2. The snap ring includes an annular receiving portion that receives the sleeve, and a protruding receiving portion that protrudes radially inward from the annular receiving portion and releasably receives the spool.

2. The fluid control valve unit according to claim 1.

3. the snap ring includes two holes for inserting an installation tool near both ends defining the notch; the opening is defined by the cutout and the two holes; 3. The fluid control valve unit according to claim 1 or 2.

4. The sleeve includes a first groove passage and a second groove passage formed in an outer wall thereof and extending in the axial direction to define the discharge passage.

4. A fluid control valve unit according to claim 1, wherein the fluid control valve unit is a valve unit.

5. The sleeve includes a communication recess in the outer wall that connects the first groove passage and the second groove passage in the circumferential direction to define the discharge passage.

5. The fluid control valve unit according to claim 4.

6. further comprising a filter member sandwiched between the end of the sleeve and the receiving portion; 6. A fluid control valve unit according to claim 1, wherein the fluid control valve unit is a valve unit.

7. The snap ring is formed in a flat plate shape extending in a direction perpendicular to the axis.

7. A fluid control valve unit according to claim 1, wherein the fluid control valve unit is a valve unit.

8. the sleeve includes an inlet through which a fluid flows in, and a first communication port and a second communication port located on both sides of the inlet in the axial direction, The spool includes a rod that reciprocates within the sleeve, a first valve portion provided on the rod and that opens and closes a passage between the inlet and the first communication port, a second valve portion provided on the rod and that opens and closes a passage between the inlet and the second communication port, and a biasing spring that applies a biasing force in a direction that causes the first valve portion to abut against the snap ring.

8. The fluid control valve unit according to claim 1, wherein the fluid control valve unit is a valve unit.

9. The discharge passage includes a first discharge passage that communicates with the first communication port to discharge the fluid when the first valve portion is closed and that communicates with the second communication port to discharge the fluid when the second valve portion is closed, and a second discharge passage that communicates with a region in which the biasing spring is disposed to discharge the fluid.

9. The fluid control valve unit according to claim 8.

10. the spool includes a compression spring disposed between the first valve portion and the second valve portion; the first valve portion includes a first fixed portion having a first land capable of closing the first communication port and a first internal passage formed inside the first land and fixed to the rod; and a first movable portion having a first cover portion for opening and closing the first internal passage and supported movably along the rod, the second valve portion includes a second fixed portion having a second land capable of closing the second communication port and a second internal passage formed inside the second land and fixed to the rod, and a second movable portion having a second cover portion for opening and closing the second internal passage and supported movably along the rod, The compression spring is arranged to exert a biasing force that closes the first lid portion and the second lid portion.

10. The fluid control valve unit according to claim 8 or 9.

11. A valve timing change device that changes the opening and closing timing of an intake valve or an exhaust valve driven by a camshaft, a housing rotor that rotates coaxially with the camshaft; a vane rotor that cooperates with the housing rotor to define an advance chamber and a retard chamber and rotates integrally with the camshaft; a fluid control valve unit according to any one of claims 8 to 10 for controlling the supply and discharge of hydraulic oil to the advance angle chamber and the retard angle chamber; the inlet of the fluid control valve unit is a supply port to which hydraulic oil is supplied, the first communication port of the fluid control valve unit is a retard port communicating with the retard chamber, the second communication port of the fluid control valve unit is an advance port communicating with the advance chamber; A valve timing change device characterized by:

12. a fastening bolt for fastening the vane rotor to the camshaft, The fastening bolt is a passage member of the fluid control valve unit.

12. The valve timing changing device according to claim 11.

13. The fluid control valve of the fluid control valve unit is a torque-driven and hydraulically-driven fluid control valve that can reciprocate hydraulic oil between the retard chamber and the advance chamber by a fluctuating torque received by the camshaft and discharge a portion of the supplied hydraulic oil.

13. The valve timing changing device according to claim 11 or 12.

14. The spool is configured such that, in a state where the spool is positioned in a retard mode in which the first valve portion is open and the second valve portion is closed, the second valve portion opens to allow the flow of hydraulic oil from the advance port to the retard port when the camshaft receives torque in a reverse direction, and, in a state where the spool is positioned in an advance mode in which the first valve portion is closed and the second valve portion is open, the first valve portion opens to allow the flow of hydraulic oil from the retard port to the advance port when the camshaft receives torque in a forward direction.

14. The valve timing changing device according to claim 13.

15. the spool is configured to block the reciprocation of hydraulic oil between the retard angle chamber and the advance angle chamber when the spool is positioned in a neutral holding mode in which the first valve portion closes the retard angle port and the second valve portion closes the advance angle port.

15. The valve timing changing device according to claim 14.

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