JP2010223100A - Cam phase variable device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operating characteristics of a cam phase varying device at a most advanced position and a most retarded position.
A cam phase varying device 20 rotates in synchronization with a crankshaft 5 and rotates integrally with a camshaft 9 and a housing 22 in which a plurality of vane chambers 61 to 63 are formed in an inner peripheral portion thereof. In addition, vanes 32 to 34 that divide the vane chamber into an advance angle chamber and a retard angle chamber are respectively provided on the outer periphery thereof and accommodated in the housing so as to be relatively rotatable between the most advanced angle position and the most retarded angle position. The rotor 21 is provided. The first vane 32 forms a first OPA 64 together with the first vane chamber 61, and at the most advanced angle position and the most retarded angle position, the advance side gap 61D or the retard angle side gap 61C is provided on the end walls 61b and 61c of the vane chamber, respectively. The advance side oil passage 91 is opened in the advance side gap, and the retard side oil passage 93 is opened in the retard side gap.
[Selection] Figure 3

Description

  The present invention relates to a cam phase varying device for an internal combustion engine.

  In an internal combustion engine mounted on an automobile or the like, a cam phase variable device (variable valve timing device) that variably controls the rotation phase of the camshaft with respect to the crankshaft in order to change the opening / closing timing of the intake valve and exhaust valve according to the operating state. , VTC). Generally, the cam phase varying device includes a housing that rotates in synchronization with a crankshaft, a rotor that rotates integrally with the camshaft, and a valve that controls the supply of hydraulic pressure. A vane chamber is formed inside the housing, and the vane chamber is formed by a vane standing on the rotor, and an advanced oil chamber (hereinafter referred to as an advance chamber) and a retard oil chamber (hereinafter referred to as a retard chamber). And). The valve changes the rotational phase of the rotor relative to the housing (that is, the rotational phase of the camshaft relative to the crankshaft) by supplying hydraulic pressure to the advance chamber or retard chamber, and controls the valve timing (for example, Patent Documents). 1).

  The vane and the corresponding vane chamber are a hydraulic pressure actuated phaser (hereinafter referred to as OPA) that rotates the rotor with respect to the housing using the hydraulic pressure supplied from the oil pump. And a cam torque driven phaser (hereinafter referred to as CTA) that rotates the rotor with respect to the housing using the cam torque applied to the camshaft. While OPA is suitable for use during high-speed operation, CTA is suitable for use during low-speed operation, so that the cam phase can be controlled with good responsiveness by combining both.

JP 2002-235513

  In order to further improve the responsiveness of OPA, it is necessary to smoothly supply hydraulic pressure to the advance chamber and the retard chamber. However, in the cam phase variable device of Patent Document 1, the advance chamber is at the most retarded position. Since the volume of the retarded chamber is substantially 0 at the most advanced angle position while the volume is substantially 0, the pressure receiving area is small at the most retarded angle position and the most advanced angle position, and response at startup There is a problem that the nature is low.

  The present invention has been made in view of the above background, and an object thereof is to improve the operation characteristics of the cam phase varying device at the most retarded position and the most advanced position.

  In order to solve the above-mentioned problem, a cam phase varying device (20) for changing the cam phase of an internal combustion engine (1) with a predetermined angle range, which rotates in synchronization with a crankshaft (5), The housing (22) in which a plurality of vane chambers (61, 62, 63) are formed on the periphery and the camshaft (9) rotate together, and the plurality of vane chambers are connected to the advance side oil chamber (61A, 62A, 63A) and the retarded side oil chambers (61B, 62B, 63B) are erected on the outer periphery of the vanes (32, 33, 34), respectively, between the most advanced position and the most retarded position. And at least one of the vanes (32, 33) is hydraulically driven phase varying means (64, 65) together with the corresponding vane chamber. No And, at the most advanced angle position and the most retarded angle position, the advance side gap (61D, 62D) or the retard angle side gap (61C, 62C) respectively on the end walls (61b, 61c, 62b, 62c) of the vane chamber. The advance side oil passages (91, 92) for supplying the advance side hydraulic pressure to the advance side oil chamber are opened in the advance side gap, and the retard side hydraulic pressure is opened in the retard side gap. The retard angle side oil passage (93, 94) for supplying the gas to the retard angle side oil chamber is opened.

  According to this configuration, the pressure receiving area is sufficiently ensured even at the most advanced angle position, so that the rotor starts to move well and the responsiveness of the cam phase varying device is improved. Similarly, at the most retarded position, the pressure receiving area of the hydraulic pressure is increased, and the operating characteristics of the cam phase varying device are improved.

  According to a second aspect, in the first aspect, at least one other of the vanes (34) is an end wall (63b, 63b) of the vane chamber (63) corresponding to the most advanced angle position and the most retarded angle position. 63c).

  According to this configuration, the most advanced angle position and the most retarded angle position can be defined by bringing the vane into contact with the end wall of the vane chamber.

  According to a third aspect, in the second aspect, the vane contacting the end wall of the corresponding vane chamber at the most retarded angle position and the most advanced angle position is a cam torque drive type phase varying means together with the corresponding vane chamber. (66).

  According to this configuration, the most advanced angle position and the most retarded position are brought about by contact between the vane and the end wall of the corresponding vane chamber without deteriorating the operation characteristics of the cam phase varying device at the most retarded angle position and the most advanced angle position. The angular position can be defined. This is because the cam torque-driven phase varying means does not use hydraulic pressure as a driving force, and therefore does not affect the operating characteristics of the cam phase varying device even if the pressure receiving area decreases at the most advanced angle position or the most retarded angle position.

  According to the above configuration, the response of the cam phase varying device can be improved.

The perspective view of the engine which concerns on embodiment 1 is an exploded perspective view of a cam phase varying device according to an embodiment. Sectional drawing which shows the most advanced angle state of the cam phase variable apparatus which concerns on embodiment Sectional drawing which shows the most retarded angle state of the cam phase variable apparatus which concerns on embodiment

  Hereinafter, an embodiment in which a cam phase varying device according to the present invention is applied to an automobile engine will be described in detail with reference to the drawings. FIG. 1 is a perspective view of an engine (internal combustion engine) 1 according to an embodiment. The engine 1 shown in FIG. 1 is a DOHC 4-valve type 4-cycle in-line 4-cylinder gasoline engine. The engine may be a diesel engine or an HCCI engine, and the number of cylinders can be arbitrarily set. A cylinder block 2 of the engine 1 includes four cylinders, and a piston 3 is slidably accommodated in each cylinder. The piston 3 is connected via a connecting rod 4 to a crankshaft 5 that is rotatably supported by the cylinder block 2.

  The cylinder head 6 provided at the upper part of the cylinder block 2 includes two intake valves 7 and exhaust valves 8 for each cylinder, and an intake camshaft 9 and an exhaust camshaft 10 that drive the intake valves 7 and the exhaust valves 8. Is provided. A crank sprocket 11 that rotates integrally with the crankshaft 5 is provided at one end of the crankshaft 5, and a cam phase varying device 20 having an intake cam sprocket 12 at one end corresponding to the crank sprocket 11 of the intake camshaft 9. Is provided. An exhaust cam sprocket 13 is provided at one end of the exhaust camshaft 10 corresponding to the crank sprocket 11. A cam chain 14 is stretched over the crank sprocket 11, the intake cam sprocket 12 and the exhaust cam sprocket 13, and the intake cam shaft 9 and the exhaust cam shaft 10 make a 1/2 rotation while the crankshaft 5 makes one rotation. .

  The engine 1 includes an oil pump 17 at a lower portion thereof. An oil pump chain 18 is stretched between the oil pump 17 and the crankshaft 5, and when the crankshaft 5 rotates, the engine oil (hydraulic oil) stored in the oil pan is driven by the oil pump 17. 1 is pumped to each part.

  2 is an exploded perspective view of the cam phase varying device 20 according to the embodiment. FIGS. 3 and 4 are sectional views of the cam phase varying device 20 according to the embodiment as viewed from the front. FIG. FIG. 4 shows the most retarded state. As shown in FIG. 2, the cam phase varying device 20 includes a rotor 21, a housing 22, a spool valve 23, a reed valve 24, and a linear solenoid 25 as main components. Hereinafter, for convenience of explanation, the side where the cam phase varying device 20 is provided (the lower left side in FIG. 2 and the front side in FIG. 3 and FIG. 4) is assumed to be the front with reference to the axial direction of the intake camshaft 9. explain.

  The rotor 21 includes a columnar base shaft portion 31 and three vanes 32 to 34 projecting radially from the outer peripheral surface of the base shaft portion 31. The first vane 32 and the third vane 34 are formed wider than the second vane 33, and the vanes 32 to 34 are arranged at an angular interval of about 120 °. A through hole 35 for accommodating the spool valve 23 is formed in the central portion of the base shaft portion 31 along the central axis.

  The rotor 21 is disposed coaxially with the intake camshaft 9 at the front end of the intake camshaft 9. A disc-shaped flange portion 44 is formed at the front end of the intake camshaft 9, and a hole 41 having the same diameter as the through hole 35 of the rotor 21 is formed at the center thereof. A boss portion 36 protrudes around the through hole 35 of the rotor 21 (see FIGS. 3 and 4), and a recess (not shown) into which the boss portion 36 is fitted is formed on the intake camshaft 9. Yes. The rotor 21 is fastened to the intake camshaft 9 by a bolt 58 in a state where the boss portion 36 is fitted (in-lobe coupling) in the recess of the intake camshaft 9.

  The housing 22 that accommodates the rotor 21 includes a back plate 51 disposed behind the rotor 21, a cylindrical cylinder 52 that covers the periphery of the rotor 21, and the intake cam sprocket 12 is formed on the outer peripheral surface thereof, and the rotor 21 and a front plate 53 disposed in front of 21. The back plate 51, the cylinder 52, and the front plate 53 are integrally fastened by bolts 54 in a state where the rotor 21 is accommodated, and the joint portions of the respective members are liquid-tight. The back plate 51 has a through hole 55 formed at the center thereof, and the inner peripheral surface of the through hole 55 is in sliding contact with the outer peripheral surface of the flange portion 44 of the intake camshaft 9. A through hole 56 is formed at the center of the front plate 53.

  As shown in FIG. 3 and FIG. 4, first to third vane chambers 61 to 63 that accommodate the first to third vanes 32 to 34 are relatively rotatable around the central axis on the inner peripheral surface of the cylinder 52. It is recessed substantially at regular intervals. Each vane chamber 61-63 includes bottom portions 61a, 62a, 63a extending in the circumferential direction of the cylinder 52, and end walls 61b, 61c, 62b rising in the radial direction of the cylinder 52 from both ends of the bottom portions 61a, 62a, 63a. , 62c, 63b, 63c. In the case of the present embodiment, the first vane 32 and the first vane chamber 61 constitute a first OPA (hydraulic drive type phase varying means) 64, and the second vane 33 and the second vane chamber 62 constitute a second OPA (hydraulic drive type phase). The third vane 34 and the third vane chamber 63 constitute a CTA (cam torque drive type phase varying means) 66.

  In the first and second vanes 32 and 33, the first and second vane chambers 61 and 62 are replaced with OPA side advance chambers (advance side oil chambers) 61A and 62A and OPA side retard chambers (retard side oil chambers), respectively. ) 61B and 62B. The third vane 34 partitions the third vane chamber 63 into a CTA side advance chamber 63A and a CTA side retard chamber 63B. The volumes of the advance chambers 61A, 62A, 63A and the retard chambers 61B, 62B, 63B vary depending on the rotational phase of the rotor 21 relative to the housing 22.

  FIG. 3 shows a state in which the rotor 21 is at the most advanced position with respect to the housing 22. In this state, the volumes of the first and second OPA side advance chambers 61A and 62A and the CTA side advance chamber 63A are maximized. As shown in FIG. 3, in the most advanced position, the third vane 34 abuts against the end wall 63b on the CTA side retarding chamber 63B side, thereby restricting the rotation of the rotor 21 toward the advanced side with respect to the housing 22. ing. At this time, a first retard angle side gap 61 </ b> C is formed between the first vane 32 and the end wall 61 b of the first vane chamber 61. That is, the first vane 32 is opposed to the end wall 61b via the first retard side gap 61C. Similarly, the second vane 33 is opposed to the end wall 62b of the second vane chamber 62 through the second retard side gap 62C at the most advanced position.

  FIG. 4 shows a state in which the rotor 21 is at the most retarded position with respect to the housing 22. In this state, the volumes of the first and second OPA-side retarded chambers 61B and 62B and the CTA-side retarded chamber 63B are maximized. As shown in FIG. 4, in the most retarded position, the third vane 34 abuts against the end wall 63c on the CTA side advance chamber 63A side, so that the rotation of the rotor 21 toward the retard side with respect to the housing 22 is restricted. ing. At this time, a first advance angle side gap 61 </ b> D is formed between the first vane 32 and the end wall 61 c of the first vane chamber 61. That is, the first vane 32 is opposed to the end wall 61c through the first advance side gap 61D. Similarly, the second vane 33 is opposed to the end wall 62c of the second vane chamber 62 through the second advance side clearance 62D at the most retarded position.

  As shown in FIG. 2, the first vane 32 is formed with a through hole 32a for receiving the lock pin 71 and the lock pin spring 72, and the back plate 51 has a lock hole (not shown) into which the lock pin 71 is fitted. ) Is formed. The lock pin 71 is fitted into the lock hole at the most retarded angle position, and is released from the lock hole when hydraulic pressure is supplied to the first and second OPA side advance chambers 61A and 62A. A rotor side seal 76 slidably contacting the inner peripheral surface of the cylinder 52 is provided at the tip of each vane 32 to 34, and a housing side seal 77 is provided on the slidable contact surface of the cylinder 52 with the base shaft portion 31 of the rotor 21. Is provided.

  A reed valve 24 is disposed on the front surface of the base shaft portion 31 of the rotor 21, and a reed valve cover 57 is disposed on the front surface of the reed valve 24. The reed valve cover 57 has a cylindrical shape and is loosely fitted in the through hole 56 of the front plate 53. The reed valve cover 57 has a through hole 57 a having the same diameter as the through hole 35 of the rotor 21 at the center thereof.

  The reed valve cover 57, the rotor 21, and the intake camshaft 9 are fastened and integrated by bolts 58, and the reed valve 24 is sandwiched between the base shaft portion 31 of the rotor 21 and the reed valve cover 57. Yes. The bolt 58 passes through a portion spaced from the central axis of the base shaft portion 31 of the rotor 21, that is, a portion located radially outward of the through hole 35, and is screwed into the flange portion 44 of the intake camshaft 9.

  A bias spring 59, which is a torsion coil spring, is interposed between the reed valve cover 57 and the front plate 53, and the housing 22 and the rotor 21 are biased by the bias spring 59 so as to be relatively rotated in the retarded direction. Has been. A linear solenoid 25 is provided in front of the reed valve cover 57. The rod 25a, which is the output shaft of the linear solenoid 25, extends to the rear of the axis of the through hole 57a of the reed valve cover 57, and the spool valve 23 disposed in the through hole 35 of the rotor 21 and the hole 41 of the intake camshaft 9. It is in contact with the front end. The linear solenoid 25 is controlled by an engine ECU (not shown) and moves the rod 25a forward and backward.

  As shown in FIG. 2, the spool valve 23 includes a hole 41 in the intake camshaft 9, a through hole 35 in the rotor 21, a valve sleeve 81 that is press-fitted into a through hole 57 a in the reed valve cover 57, and a valve sleeve 81. The spool 82 is slidably fitted therein, and a return spring 83 disposed behind the spool 82 in the valve sleeve 81 so as to bias the spool 82 forward (on the linear solenoid 25 side). The spool 82 has a bottomed cylindrical shape with an opening on the return spring 83 side, and an open end is closed by a plug (not shown) so as to form a hollow portion therein.

  In the spool valve 23, the spool 82 is driven to the rear side of the axis by the rod 25a of the linear solenoid 25, or the spool 82 is driven (returned) to the front side of the axis (linear solenoid 25 side) by the urging force of the return spring 83. The oil passage is switched accordingly. The spool valve 23 is mainly maintained in three states: an advanced state in which the spool 82 is positioned on the rear side of the axis, a retarded state in which the spool 82 is positioned on the front side of the axis, and a holding state in which the spool 82 is in the intermediate position. Is done. During operation of the engine 1, hydraulic oil is constantly supplied from the oil pump 17 to the spool valve 23 via the oil passage 19. The oil passage 19 is formed in the cylinder block 2, the intake camshaft bearing (not shown), and the intake camshaft 9.

  Next, an oil passage structure for supplying hydraulic oil to the first to third vane chambers 61 to 63 will be described. The rotor 21 and the intake camshaft 9 are in communication with the first OPA-side advance oil passage 91 that communicates the first OPA-side advance chamber 61A and the spool valve 23, and the second OPA-side advance chamber 62A and the spool valve 23. A second OPA side advance oil passage 92 is formed. Further, the rotor 21 and the reed valve cover 57 include a first OPA-side retarded oil passage 93 that communicates the first OPA-side retarded chamber 61B and the spool valve 23, and a second OPA-side retarded chamber 62B and the spool valve 23. A second OPA-side retarded oil passage 94 that communicates is formed. The rotor 21 has a first CTA oil passage 95 that communicates the CTA side advance chamber 63A and the spool valve 23, a second CTA oil passage 96 that communicates the CTA side retard chamber 63B and the spool valve 23, and a first CTA oil. A central oil passage (not shown) that communicates the passage 95 and the spool valve 23 and communicates the second CTA oil passage 96 and the spool valve 23 is formed.

  The spool valve 23 communicates with the first OPA-side advance oil passage 91 and the second OPA-side advance oil passage 92 in the advance state, and supplies hydraulic pressure to the first OPA-side advance chamber 61A and the second OPA-side advance chamber 62A. At the same time, one end of the first OPA-side retarded oil passage 93 and the second OPA-side retarded oil passage 94 is released, and the hydraulic oil in the first OPA-side retarded chamber 61B and the second OPA-side retarded chamber 62B is allowed to flow out. At the same time, the spool valve 23 communicates the second CTA oil passage 96 and the central oil passage.

  In the retarded state, the spool valve 23 communicates with the first OPA-side retarded oil passage 93 and the second OPA-side retarded oil passage 94, and hydraulically supplies the first OPA-side retarded chamber 61B and the second OPA-side retarded chamber 62B. And one end of the first OPA-side advance oil passage 91 and the second OPA-side advance oil passage 92 are released, and the hydraulic oil in the first OPA-side advance chamber 61A and the second OPA-side advance chamber 62A flows out. At the same time, the spool valve 23 communicates the first CTA oil passage 95 and the central oil passage.

  When the spool valve 23 is in the holding state, the first OPA-side advance oil passage 91, the second OPA-side advance oil passage 92, the first OPA-side retard oil passage 93, the second OPA-side retard oil passage 94, and the first CTA oil The oil passages of the passage 95, the second CTA oil passage 96, the central oil passage and the spool valve 23 are disconnected, and the oil pressure of each oil chamber is maintained.

  As shown in FIG. 3, one end of the first OPA-side retarded oil passage 93 opens to a portion where the first retarded-side gap 61 </ b> C is formed on the outer peripheral surface of the base shaft portion 31 of the rotor 21, and the second OPA side One end of the retard oil passage 94 is open to a portion where the second retard side gap 62 </ b> C is formed on the outer peripheral surface of the base shaft portion 31 of the rotor 21. Further, as shown in FIG. 4, one end of the first OPA-side advance oil passage 91 opens to a portion where the first advance-side gap 61D is formed on the outer peripheral surface of the base shaft portion 31 of the rotor 21, One end of the 2OPA-side advance oil passage 92 opens to a portion where the second advance-side gap 62D is formed on the outer peripheral surface of the base shaft portion 31 of the rotor 21.

  The reed valve 24 includes first and second valve bodies (not shown). The first valve body is interposed between the central oil passage and the first CTA oil passage 95, and the first CTA oil passage 95 extends from the central oil passage. While allowing the flow of hydraulic oil to the center, the flow of hydraulic oil from the first CTA oil passage 95 to the central oil passage is prohibited. Further, the second valve body is interposed between the central oil passage and the second CTA oil passage 96, and allows the flow of hydraulic oil from the central oil passage to the second CTA oil passage 96, while from the second CTA oil passage 96. The flow of hydraulic oil to the central oil passage is prohibited.

  Next, the operation of this embodiment will be described with reference to FIGS. As shown in FIG. 3, when the spool valve 23 is retarded from the state where the rotor 21 is in the most advanced position, the first OPA-side retarding chamber 61 </ b> B (first The hydraulic pressure is supplied to the retard side gap 61C), and the hydraulic pressure is supplied to the second OPA side retard chamber 62B (second retard side gap 62C) via the second OPA side retard oil passage 94. It rotates in the direction shown by arrow A in the figure. At this time, in the CTA 66, the hydraulic oil in the CTA side advance chamber 63A passes through the first CTA oil passage 95, the spool valve 23, the central oil passage, the reed valve 24, and the second CTA oil passage 96 in this order. Flow into.

  As shown in FIG. 4, when the spool 21 is advanced from the state where the rotor 21 is at the most retarded position, the first OPA side advance chamber 61 </ b> A (first The hydraulic pressure is supplied to the advance angle side gap 61D), the hydraulic pressure is supplied to the second OPA side advance angle chamber 62A (second advance angle side gap 62D) via the second OPA side advance angle oil passage 92, and the rotor 21 It rotates in the direction shown by arrow B in the figure. At this time, in the CTA 66, the hydraulic oil in the CTA side retarding chamber 63B passes through the second CTA oil passage 96, the spool valve 23, the central oil passage, the reed valve 24, and the first CTA oil passage 95 in this order. Flow into.

  In the present embodiment, the first retarded angle side gap 61C and the second retarded angle side gap 62C are formed at the most advanced angle position, and the first OPA side retarded oil passage 93 opens to the first retarded angle side gap 61C. Since the second OPA-side retarded oil passage 94 opens into the second retarded-side gap 62C, the pressure receiving areas of the first and second OPA-side retarded chambers 61B and 62B are increased when driven in the retarded direction from the most advanced position. It can be secured sufficiently wide from the beginning. Therefore, a large driving force can be generated in the first and second OPA 64 and 65 of the variable phase control from the beginning of the retard driving, and the responsiveness of the cam phase varying device 20 can be improved. Similarly, for the most retarded position, the response of the cam phase varying device 20 is determined by the first advance side clearance 61D, the second advance side gap 62D, the first OPA side advance oil passage 91, and the second OPA side advance oil passage 92. It becomes possible to improve the property.

  Further, since the most advanced angle position and the most retarded angle position are defined by bringing the third vane 34 constituting the CTA 66 into contact with the end walls 63b and 63c of the third vane chamber 63, the response of the cam phase varying device 20 There is no loss of sex. This is because the CTA 66 is driven by cam torque.

  Although the description of the specific embodiment is finished as above, the present invention is not limited to the above embodiment and can be widely modified. In the present embodiment, the opening ends of the first OPA side advance oil passage 91 and the second OPA side advance oil passage 92 are formed on the outer peripheral surface of the base shaft portion 31 of the rotor 21, but in other embodiments, the first OPA side The advance angle oil passage 91 and the second OPA side advance angle oil passage 92 are not passed through the base shaft portion 31 of the rotor 21 but from the flange portion 44 of the intake camshaft 9 to the first advance angle side clearance 61D and the second advance angle side clearance. You may make it open directly to 62D. Similarly, the first OPA-side retarded oil passage 93 and the second OPA-side retarded oil passage 94 are connected to the first retarded-side gap 61 </ b> C and the second retarded-side gap 61 </ b> C from the reed valve cover 57 without passing through the base shaft portion 31 of the rotor 21. You may make it open directly to the retard side gap | interval 62C.

  1 .... Engine (internal combustion engine), 5 .... Crankshaft, 9 .... Intake camshaft, 20 .... Cam phase variable device, 21 ... Rotor, 22 .... Housing, 23 ... Spool valve, 24 ... Lead Valves 25 ·· Linear solenoids 32, 33, 34 · · 1st to 3rd vanes 51 · · Back plate 52 · · Cylinder 53 · · Front plate 57 · · Reed valve cover 61 · 63 · · First to third vane chambers, 61A, 62A · · OPA side advance chamber (advance side oil chamber), 61B, 62B · · OPA side retard chamber (retard side oil chamber), 61C, 62C · · 1st, 2nd retard angle side gap, 61D, 62D... 1st, 2nd advance angle side gap, 61b, 61c, 62b, 62c, 63b, 63c .. End wall, 64, 65. 2OPA (hydraulic drive type phase variable means) 66 ·· CTA (cam torque drive type phase varying means), 91 · · First OPA side advance oil passage, 92 · · Second OPA side advance oil passage, 93 · · First OPA side retard oil passage, 94 · · · 2OPA retarded oil passage

Claims (3)

A cam phase variable device that changes a cam phase of an internal combustion engine with a predetermined angle range,
A housing that rotates in synchronization with the crankshaft and has a plurality of vane chambers formed on the inner periphery thereof;
A vane that rotates integrally with the camshaft and that divides the plurality of vane chambers into an advance angle side oil chamber and a retard angle side oil chamber is provided on the outer periphery thereof, and the most advanced angle position and the most retarded angle position And a rotor housed in the housing so as to be relatively rotatable between,
At least one of the vanes forms a hydraulically driven phase variable means together with the corresponding vane chamber, and an advance side gap is provided in an end wall of the vane chamber at the most advanced position and the most retarded position, respectively. Or confront with a retarded side gap,
The advance side oil passage for supplying the advance side hydraulic pressure to the advance side oil chamber opens in the advance side gap, and the retard side hydraulic pressure is supplied to the retard side oil chamber in the retard side gap. A cam phase varying device characterized in that a retarded oil passage is opened.   2. The cam phase varying device according to claim 1, wherein at least one other of the vanes contacts an end wall of a corresponding vane chamber at the most advanced angle position and the most retarded angle position.   The said vane which contact | abuts the end wall of the said corresponding vane chamber in the said most retarded angle position and the said most advanced angle position makes a cam torque drive type phase variable means with the said corresponding vane chamber, It is characterized by the above-mentioned. The cam phase varying device described in 1.

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