WO2017104246A1

WO2017104246A1 - Valve timing control device for internal combustion engine

Info

Publication number: WO2017104246A1
Application number: PCT/JP2016/080510
Authority: WO
Inventors: 徹四宮
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2015-12-18
Filing date: 2016-10-14
Publication date: 2017-06-22
Also published as: US20200088071A1; MX2018007344A; JPWO2017104246A1; CN108368756A; DE112016005764T5

Abstract

A valve timing control device is provided with: a bolt insertion hole 7a which is formed in an extending manner at a position axially facing a bolt hole 2b formed in the camshaft 2 of the rotor section 21 of a vane rotor 7 and through which the shaft section 6b of a cam bolt 6 is inserted; a radial groove 52, an axial groove 53, and a passage groove 54, which are formed on the front end side of the vane rotor so as to extend radially and axially from the bolt insertion hole and which are in communication with a back-pressure chamber 29d; and a discharge passage 56 which is formed between the inner peripheral surface of the bolt hole and the outer peripheral surface of the shaft section of the cam bolt, has one end in communication with the passage groove 54, and has the other end in communication with a drain hole 57 formed in the camshaft. As a result, a passage for discharging air, etc. within the back-pressure chamber can be formed without increasing the outer diameter of the vane rotor, and consequently, an increase in the size of the entire valve timing control device can be reduced.

Description

Valve timing control device for internal combustion engine

The present invention relates to a valve timing control device for an internal combustion engine that variably controls the opening / closing timing of an intake valve and an exhaust valve of the internal combustion engine according to an operating state.

As a conventional valve timing control device, for example, there is one described in Patent Document 1 below applied to the exhaust valve side.

The valve timing control device includes a housing in which rotational force is transmitted from a crankshaft via a timing belt, a vane rotor that is housed in the housing so as to be relatively rotatable and fixed to an end of a camshaft, It is provided in a sliding hole formed in the inner axial direction of the vane rotor so as to be movable, and the tip portion engages with a lock hole formed in the rear plate of the housing to restrict relative rotation of the vane rotor with respect to the housing. A lock pin, a coil spring that is elastically mounted on the rear side of the sliding hole and biases the lock pin in the direction of the lock hole, and is formed so as to penetrate in the direction of the internal axis of the vane rotor. And a communication hole leading into the engine.

Further, a torsion spring is provided inside the front end of the housing, one end of which is fixed to the front plate of the housing and the other end is engaged and fixed to the communication hole to relatively rotate the vane rotor to the advance side.

Then, when the engine is started, the hydraulic pressure supplied from the oil pump to the retarded oil chamber via the electromagnetic switching valve is simultaneously supplied to the pressure receiving chamber formed in the lock hole. With this hydraulic pressure, the lock pin moves backward against the spring force of the coil spring, and the lock with respect to the lock hole is released.

JP 2011-132404 A

However, in the valve timing control device described in Patent Document 1, the communication hole for discharging hydraulic oil from the back pressure chamber is formed so as to penetrate in the direction of the internal axis of the vane rotor. The outer diameter of the vane rotor must be increased by an amount corresponding to the penetration formation to ensure a formation space. For this reason, the radial size of the entire apparatus including the vane rotor and the housing is inevitably increased.

An object of the present invention is to provide a valve timing control device capable of suppressing an increase in overall size by forming a passage for discharging oil and air in a back pressure chamber without increasing the outer diameter of the vane rotor. .

As a preferred aspect of the present invention, one end of the camshaft is provided by a cam bolt inserted into the housing through which the rotational force is transmitted from the crankshaft and a hydraulic oil chamber is provided, a bolt insertion hole, and the bolt insertion hole. And a vane rotor which is accommodated in the housing so as to be relatively rotatable and which separates the hydraulic oil chamber from the retarded working chamber and the advanced working chamber, and a lock formed on the inner end surface of the housing. A hole and a sliding hole formed in the inner axial direction of the vane rotor are movably provided, and an axial tip is engaged with and disengaged from the lock hole to lock the relative rotational position of the vane rotor with respect to the housing. Or a locking member for releasing the lock, and a back pressure chamber provided on the front side opposite to the camshaft of the sliding hole. A biasing member that biases the lock member in the direction of the lock hole, a communication passage communicating with the vane rotor with the bolt insertion hole and the back pressure chamber, an inner peripheral surface of the bolt insertion hole, and a shaft of the cam bolt An annular passage that is formed between the outer peripheral surface of the portion and has one end communicating with the communication passage and the other end communicating with a drain hole formed in the camshaft.

According to the present invention, enlargement of the apparatus in the radial direction can be suppressed.

It is sectional drawing which shows one Embodiment of the valve timing control apparatus which concerns on this invention. It is a disassembled perspective view which shows a part of valve timing control apparatus of this embodiment. It is a front view which removes a front plate and shows the state which controlled the valve timing to the retard side by the embodiment. It is a principal part enlarged view of the valve timing control apparatus shown in FIG. FIG. 2 is a sectional view taken along line AA in FIG. 1.

Hereinafter, an embodiment in which a valve timing control device for an internal combustion engine according to the present invention is applied to an intake valve side will be described with reference to the drawings.

As shown in FIGS. 1 to 4, the valve timing control device includes a timing pulley 1 that is rotationally driven via a timing belt by a crankshaft (not shown) of the engine, and is rotatable relative to the timing pulley 1. , A phase conversion mechanism 3 disposed between the timing pulley 1 and the camshaft 2 for converting the relative rotational phases of the two and 1 and the operation of the phase change mechanism 3. And a lock mechanism 4 for locking.

The timing pulley 1 is formed integrally with a housing body 11 described later, and integrally has a plurality of gear portions 1a around which a timing belt (not shown) is wound.

The camshaft 2 is rotatably supported by a cylinder head (not shown) via a cam bearing, and a plurality of drive cams that open the intake valve (not shown) against a spring force of a valve spring at a predetermined position on the outer peripheral surface. Are provided integrally. Further, the camshaft 2 is formed with a bolt hole 2b through which a shaft portion 6b of a cam bolt 6 to be described later is inserted in the inner axial direction of the one end portion 2a. A female screw hole 2c into which a male screw portion 6d formed on the outer peripheral surface of the tip portion of the shaft portion 6b is screwed is formed on the tip side of the bolt hole 2b.

The cam bolt 6 is formed on the outer periphery of the hexagonal head portion 6a, the shaft portion 6b integrally provided at one end portion of the head portion 6a via a flange-shaped seat portion 6c, and the distal end portion of the shaft portion 6b. The male threaded portion 6d.

The phase conversion mechanism 3 includes a housing 5 disposed on the one end 2 a side of the camshaft 2, and is fixed to the one end 2 a of the camshaft 2 from the axial direction by the cam bolt 6 so as to be relatively rotatable in the housing 5. The vane rotor 7, the four first to fourth shoes 8a to 8d formed in the housing 5 and integrally formed on the inner peripheral surface of the housing body 11 to be described later, and the four vanes 22 to the vane rotor 7 to be described later. 25, each of the retard oil chamber 9 and the advance oil chamber 10 which are the advance oil chambers, and each retard oil chamber 9 and each advance oil chamber 10 separated by 25 respectively. A hydraulic circuit that selectively supplies and discharges hydraulic pressure.

The housing 5 includes a substantially cylindrical housing main body 11 having both ends opened in the axial direction, a front plate 12 closing the axial front end opening of the housing main body 11, and a rear closing the axial rear end opening of the housing main body 11. Plate 13. The housing main body 11, the front plate 12, and the rear plate 13 are integrally coupled together by four bolts 14 from the axial direction.

The housing body 11 is integrally formed of a sintered metal material, the timing pulley 1 is integrally provided on the outer periphery, and the four first to second positions are arranged at substantially equal intervals in the circumferential direction of the inner peripheral surface. Four shoes 8a to 8d are integrally projected inward.

Each of the shoes 8a to 8d is formed in a substantially trapezoidal shape when viewed from the side, and a substantially U-shaped seal member 16 is fitted and fixed in a seal groove formed along the axial direction at each tip portion. ing. Further, bolt insertion holes 17 through which the bolts 14 are inserted are formed in the radially outer peripheral sides of the shoes 8a to 8d, that is, in the inner axial direction on the base portion side that is a connecting portion to the inner peripheral surface of the housing body 11. Has been.

Further, the front end surface of the housing body 11 is formed with a double-leaf-shaped first seal groove 11a into which a first seal member 15 for sealing between the front end surface of the housing body 11 and the front plate 12 is fitted and fixed. Has been.

The front plate 12 is formed in a relatively thin metal disk shape by forging, casting, pressing, or the like, and has a large diameter into which the head 6a of the cam bolt 6 can be fitted inside a cylindrical portion 12a that is integrally provided at the center. A hole 12b is formed. In addition, four bolt insertion holes 12c through which the respective bolts 14 are inserted are formed in the circumferentially equidistant positions on the outer peripheral side of the front plate 12.

Further, a plug 18 that closes the large-diameter hole 12b is attached to the cylindrical portion 12a of the front plate 12. The plug 18 is formed in a cylindrical shape with a lid, and an external thread portion 18b is formed on the outer periphery of the cylindrical portion 18a. The external thread portion 18b is formed on the inner peripheral surface of the large-diameter hole 12b. A hexagonal portion 18d with which a tool such as a spanner engages is integrally provided at the center of the outer surface of 18c. A seal ring 26 is fitted and fixed between the inner surface of the outer peripheral portion of the lid wall 18c and the cylindrical portion 12a.

The rear plate 13 is formed into a metal disk shape by forging, casting, or pressing, and a support hole that is an insertion hole in which the one end 2a of the camshaft 2 is inserted and rotatably supported at the center. 13a is penetratingly formed. In addition, four female screw holes 13b into which the male screw portions at the tip portions of the respective bolts 14 are screwed are formed at circumferentially equidistant positions on the outer peripheral side of the rear plate 13. The rear plate 13 is integrally formed with a cylindrical portion 13c extending along the axial direction so as to cover the outer peripheral surface of the camshaft 2 at the hole edge of the support hole 13a.

Further, on the inner end surface of the rear plate 13, four advance angle side oil grooves 19 that are second oil passages communicating with each advance angle oil chamber 10 are formed radially from the center of the support hole 13a. Formed on the outer peripheral side of the inner end surface is a double-leaf-shaped second seal groove 13d in which a second seal member 27 for sealing between the rear end surface of the housing body 11 and the rear plate 13 is fitted and fixed.

The vane rotor 7 is integrally formed of sintered metal, and is a cylinder fixed from the axial direction to one end 2a of the camshaft 2 by a cam bolt 6 inserted from the axial direction into a bolt insertion hole 7a formed at the center. And the four first to fourth vanes 22 to 25 projecting radially from the outer circumferential surface of the rotor portion 21 at substantially equal intervals in the circumferential direction.

The rotor portion 21 is configured to rotate while sliding on the seal member 16 that is fitted and fixed to the upper surface of the tip of each shoe 8a to 8d on the outer peripheral surface. Further, as shown in FIG. 3, the rotor portion 21 has four retarded-side oil holes 20 communicating with the retarded oil chambers 9 in the radial direction on both sides of the vanes 22 to 25 along the radial direction. Each is formed through. Further, as shown in FIGS. 1 and 3, a first fitting groove 21 a into which the tip of one end 2 a of the camshaft 2 is fitted is formed at the center of the end surface of the rotor portion 21 on the camshaft 2 side. On the other hand, as shown in FIGS. 1 and 2, a second fitting groove 21 b into which the seat portion 6 c of the cam bolt 6 is fitted is formed at the center of the end surface on the front plate 12 side. The bottom surface of the second fitting groove 21b is formed as a seating surface 21c on which the end surface of the seat portion 6c is seated.

As shown in FIG. 3, the vanes 22 to 25 are arranged between the shoes 8a to 8d, respectively. In addition, substantially U-shaped seal members 28 that are in sliding contact with the inner peripheral surface 11a of the housing main body 11 are fitted and fixed in seal grooves formed in the axial direction on the respective front end surfaces.

In each of the vanes 22 to 25, the first vane 22 is formed to have the maximum width, and the other three second to fourth vanes 23 to 25 are sufficiently smaller in width than the first vane 22 and substantially the same width. Is set to In this way, the weight balance of the entire vane rotor 7 is made uniform by reducing the widths of the other three vanes 23 to 25 with respect to the first vane 22 having the maximum width.

When the vane rotor 7 rotates in the maximum counterclockwise direction shown in FIG. 3, the first vane 22 abuts one side surface against the opposite side surface of the first shoe 8 a and restricts the relative rotational position on the maximum retard angle side with respect to the housing 5. It has come to be. Further, when the vane rotor 7 rotates in the maximum clockwise direction, the first vane 22 comes into contact with the opposite side surface of the second shoe 8b and the relative rotational position on the maximum advance side is restricted. ing.

When the first vane 22 is in contact with the first and

second shoes

8a and 8b, the other vanes 23 to 25 are not in contact with any of the shoes 8a to 8d that are opposed in the circumferential direction. It has become.

As shown in FIGS. 1 to 4, the lock mechanism 4 includes a sliding hole 29 formed through the first vane 22 in the direction of the internal axis, and is slidably accommodated in the sliding hole 29, so that the rear The vane rotor 7 is formed by a lock pin 30 which is a lock member provided so as to be movable back and forth with respect to the plate 13 side and a substantially central predetermined position in the radial direction of the rear plate 13. The lock hole 31 is a lock recess that locks the lock pin 31 and the engagement / disengagement mechanism that engages or disengages the tip of the lock pin 30 with the lock hole 31 in accordance with the starting state of the engine. Yes.

The sliding hole 29 has an inner peripheral surface formed in a stepped diameter shape, and has a small diameter hole 29a on the front end side on the rear plate 13 side and a large diameter hole 29b on the rear end side. The small diameter hole 29a and the large diameter An annular first step portion 29c is formed between the hole 29b.

As shown in FIGS. 2 and 5, the lock pin 30 has a small-diameter portion including a tip end portion that slides in the small-diameter hole 29a and has an outer peripheral surface formed in a stepped diameter shape corresponding to the lock hole 31 and the sliding hole 29. 30a, a large-diameter portion 30b which is provided on the outer periphery of the rear end portion and slides in the large-diameter hole 29b, and a second step portion 30c formed between the small-diameter portion 30a and the large-diameter portion 30b. is doing. The tip of the small diameter portion 30a is solid, and the outer peripheral surface is formed in a columnar shape.

In the lock hole 31, an annular guide ring 31a that slides and guides the tip of the lock pin 30 is press-fitted and fixed to the inner peripheral surface. The lock hole 31 is formed at a position near the advance oil chamber 10 in the circumferential direction, that is, at a position facing the lock pin 30 from the axial direction when the vane rotor 7 rotates relative to the maximum retard angle side. Is formed. Therefore, when the lock pin 30 is engaged with the lock hole 31, the relative rotation angle between the housing 5 and the vane rotor 7 is set to be the maximum retard conversion angle that is optimal for engine starting.

Also, an annular pressure receiving chamber 33 is formed between the first step portion 29 c of the sliding hole 29 and the second step portion 30 d of the lock pin 30. The pressure receiving chamber 33 constitutes a part of a release oil passage described later.

Further, the sliding hole 29 is formed with a back pressure chamber 29d separated in cooperation with the lock pin 30 at the rear end.

The engagement / disengagement mechanism is elastically mounted between the inner bottom surface of the cylindrical groove formed in the inner axial direction on the rear end side of the lock pin 30 and the inner end surface of the front plate 12, and moves the lock pin 30 in the advancing direction (lock hole). 31) and a release passage that supplies hydraulic pressure into the pressure receiving chamber 33 to move the lock pin 30 backward against the spring force of the coil spring 32.

When the vane rotor 7 rotates relative to the maximum retard angle phase position, the coil spring 32 moves the lock pin 30 forward by the spring force and engages the tip of the lock pin 30 into the lock hole 31. The vane rotor 7 is locked with respect to the housing 5.

As shown in FIG. 3, the release passage is formed in the inner circumferential direction across the sliding hole 29 of the first vane 22, and is supplied to the retarded oil chamber 9 and the advanced oil chamber 10, respectively. Are formed by two first oil holes 41a and second oil holes 41b, respectively, for supplying the pressure to the pressure receiving chamber 33.

That is, the first oil hole 41a is formed in the inside along the width direction of the first vane 22 from one end opening formed on one side face of the first vane 22 facing the one advance oil chamber 10, and the other end The opening faces the pressure receiving chamber 33. On the other hand, the second oil hole 41b is formed inside the first vane 22 along the same width direction from the one end opening of the first vane 22 facing the retarded oil chamber 9, and the other end opening. Faces the same pressure receiving chamber 33 from the opposite side.

The hydraulic pressure supplied from the

oil holes

41a and 41b to the pressure receiving chamber 33 acts on the second step portion 30c to cause the lock pin 30 to resist the spring force of the coil spring 32 in the disengagement direction, that is, to move backward. The engagement with the lock hole 31 at the front end of the lock pin is released to allow free relative rotation of the vane rotor 7 with respect to the housing 5.

Also, positioning means is provided between the camshaft 2 and the vane rotor 7 for positioning the camshaft 2 and the vane rotor 7 in the circumferential direction when these are fastened by the cam bolts 6.

As shown in FIGS. 1 and 4, the positioning means includes a pin fixing hole 35a (a part of an advance side passage 35 described later) formed in the internal axial direction from the distal end surface of the one end 2a of the camshaft 2. The positioning pin 50 whose base end portion is press-fitted and fixed to the first fitting groove 21a from the seating surface 21c of the second fitting groove 21b of the rotor portion 21 is engaged with the distal end portion 50a of the positioning pin 50. And a U-shaped positioning hole 51 to be joined.

The hydraulic circuit selectively supplies hydraulic pressure to each retard / advance

oil chamber

9, 10 or discharges the oil in each retard / advance

oil chamber

9, 10. Specifically, as shown in FIGS. 1 and 5, a pair of retarded sides formed in one end portion 2 a of the camshaft 2 in the inner axial direction and the radial direction and communicated with the retarded side oil holes 20. An advance side passage 35 that is formed in parallel with each retard angle side passage 34 in the inner axial direction and the radial direction from one end portion 2a of the camshaft 2 and communicates with each advance angle side oil groove 19. , An electromagnetic switching valve 36 provided between the

passages

34, 35, an oil pump 37 that selectively supplies hydraulic pressure to the

passages

34, 35 via the electromagnetic switching valve 36, and each retard side, advance angle And a drain passage 38 that selectively communicates with the

side passages

34 and 35 via an electromagnetic switching valve 36. Note that the suction passage 37 a and the drain passage 38 of the oil pump 37 communicate with the oil pan 39.

Each of the retard side and advance

side passages

34 and 35 communicates with the retard port and advance port of the electromagnetic switching valve 36 at one end and the other end via a groove groove (not shown). The oil grooves 19 and the oil holes 20 communicate with each other.

The electromagnetic switching valve 36 is a four-port three-position valve, and selectively selects each retardation port, advance port, discharge passage 37a and drain passage 38 of the oil pump 37 by an output signal from a controller (not shown). Switching control is performed.

The controller detects the current engine operating state by inputting information signals from various sensors such as a crank angle sensor, an air flow meter, a water temperature sensor, a throttle valve opening sensor, etc., which are not shown in the figure. A control current is output to the solenoid of the electromagnetic switching valve 36 in accordance with the engine operating state.

In FIG. 1, 40 is a pilot-type pressure control valve provided on the downstream side of the discharge passage 37b of the

oil pump

37, and 41 is a filter.

The rotor portion 21 of the vane rotor 7, the first vane 22, the camshaft 2, etc. communicate with the back pressure chamber 29 d of the sliding hole 29 and the outside, and hydraulic oil or air that flows into the back pressure chamber 29 d. A discharging means is provided for discharging the air to the outside and ensuring good slidability of the lock pin 30 in the sliding hole 29.

As shown in FIGS. 1 to 4, the discharge means is a second communication groove formed along the radial direction from the inner edge of the back pressure chamber 29d on the front end surface of the first vane 22 on the front plate 12 side. A certain axial groove 52 and an axial groove 53 that is a first communication groove formed along the axial direction on the inner peripheral surface of the second fitting groove 21 b of the rotor portion 21 and having one end communicating with the radial groove 52. And a passage groove 54 formed between the axial groove 53 and the positioning hole 51 and formed along the radial direction on a seating surface 21c on which the seat 6c of the cam bolt 6 is seated, and a bolt of the rotor 21 An annular passage 55 that is formed between the inner peripheral surface of the insertion hole 7a and the shaft portion 6b and communicates with the passage groove 54 via the positioning hole 51, and the inner periphery of the bolt hole 2b of the camshaft 2 Is formed between the surface of the cam bolt 6 and the outer peripheral surface of the cam bolt 6, and has one end 56 a in the axial direction. A cylindrical discharge passage 56 communicating with the annular passage 55 and the inside of the one end portion 2a of the camshaft 2 are formed along the radial direction, and an inner end opening communicates with the other end side of the discharge passage 56. The drain hole 57 is mainly composed of.

Further, a cylindrical drain groove 58 is formed along the axial direction on the inner peripheral surface of the cylindrical portion 13c of the rear plate 13. The drain groove 58 has one end 58a in the axial direction at the camshaft 2. An opening is formed in the vicinity of the flange portion 2d provided integrally with the outer periphery of the one end portion 2a so as to communicate with the outside.

The radial groove 52 is coupled to the axial groove 53 from a right angle direction, and one end opening faces the side edge of the back pressure chamber 29d.

The axial groove 53 is simply formed by cutting out a part of the inner peripheral surface of the second fitting groove 21b of the rotor portion 21 and extending along the axial direction up to the seating surface 21c. While being shortened, the inner end faces the edge of the positioning hole 51.

The radial groove 52, the axial groove 53, the passage groove 54, and the positioning hole 51 are formed in a cross-sectional crank shape and continuously communicate with the discharge passage 56, the drain hole 57, and the drain groove 58 on the downstream side.
[Operation of this embodiment]
Hereinafter, the operation of the present embodiment will be described. First, when the engine is stopped, the pump operation of the oil pump 37 is stopped and the supply of hydraulic oil to the

oil chambers

9 and 10 is stopped. For this reason, as shown in FIG. 3, the vane rotor 7 rotates relative to the maximum retarded angle position by the alternating torque acting on the camshaft 2, and the tip of the lock pin 30 is locked by the spring force of the coil spring 32 at this position. The vane rotor 7 is engaged in the hole 31 and locked at the most retarded position optimum for starting.

Next, when starting is started by turning on the ignition switch, that is, in the initial stage of cranking, the controller maintains the non-energized state of the coil of the electromagnetic switching valve 36. As a result, as shown in FIG. 1, the discharge passage 37b of the oil pump 37 and the retard side passage 34 are made to communicate with each other, and at the same time, the advance side passage 35 and the drain passage 38 are made to communicate with each other.

Therefore, the hydraulic oil discharged from the oil pump 37 flows into each retarded oil chamber 9 through the electromagnetic switching valve 36, the retarded-side passage 34, etc., and the retarded oil chamber 9 becomes high pressure. The hydraulic oil in each advance oil chamber 10 passes through the advance side passage 35 and is discharged from the drain passage 38 into the oil pan 39, and the inside of each advance oil chamber 10 becomes low pressure.

Therefore, the vane rotor 7 is maintained in the locked state at the initial stage of the cranking at the start of the engine, and is at the most retarded relative rotational position. Therefore, the smooth cranking not only provides good startability, but also suppresses flapping and suppresses interference between the vanes 22 to 25 and the shoes 8a to 8d. As a result, it is possible to sufficiently suppress the occurrence of hitting sound due to such interference. In particular, it is possible to sufficiently suppress the occurrence of interference hitting sound between the first vane 22 and the

shoes

8a and 8b.

The pump discharge pressure is supplied from each oil hole 20 to each retarded oil chamber 9, and this hydraulic pressure also flows into the pressure receiving chamber 33 from the second communication hole 41b, thereby increasing the pressure of the lock pin 30. The tip part moves backward from the lock hole 31 and the free rotation of the vane rotor 7 with respect to the housing 5 is ensured.

However, as the volume of each retarded oil chamber 9 is maintained in an enlarged state, the vane rotor 7 is rotated counterclockwise as shown in FIG. It abuts against the opposite side surface of the first shoe 8a, and further counterclockwise rotation is restricted. Thereby, the relative rotation angle of the vane rotor 7, that is, the camshaft 2 is maintained at the most retarded angle side with respect to the housing 5 (timing pulley 1).

Next, when the engine shifts to a predetermined engine operation state such as an idling operation, a control current is output from the controller to the electromagnetic switching valve 36 to start operation, and the discharge passage 37b and the advance side passage 35 are communicated. At the same time, the retard side passage 34 and the drain passage 38 are connected. As a result, the hydraulic oil in each retarded oil chamber 9 is discharged and becomes low pressure, and the hydraulic oil is supplied to each advanced oil chamber 10 and the inside becomes high pressure. At this time, since the hydraulic pressure is supplied from the one advance oil chamber 10 to the pressure receiving chamber 33 through the first communication hole 41a, the lock pin 30 is kept out of the lock hole 31 by this hydraulic pressure.

For this reason, the vane rotor 7 rotates relative to the housing 5 in the clockwise direction, and the other side surface of the first vane 22 abuts against the opposite side surface of the second shoe 8b, and further clockwise rotation is restricted. . Thereby, the relative rotation phase of the camshaft 2 with respect to the timing pulley 1 is converted to the most advanced angle side. As a result, the opening / closing timing of the intake valve is controlled to the most advanced angle side, and the performance of the engine in such an operating region can be improved.

In this embodiment, the oil or air that has flowed into the back pressure chamber 29 d flows from the annular groove 55 into the discharge passage 56 through the radial groove 52, the axial groove 53, the passage groove 54, and the positioning hole 51. To do. Further, since it can be quickly discharged to the outside through the drain hole 57 and the drain groove 58 through the flange portion 2d formed on the outer periphery of the one end portion 2a of the camshaft 2, the axial movement of the lock pin 30, that is, the lock The engagement / disengagement movement to the hole 31 is improved.

In addition, the inner peripheral surface of the second fitting groove 21b formed in the rotor portion 21 is not formed in the axial direction of the rotor portion, such as a passage as a discharging means, like the communication hole of the prior art described above. The axial groove 53 having a short length and the existing positioning hole 51 were used. Further, the discharge passage 56 is formed using a gap between the inner peripheral surface of the bolt hole 2 b of the camshaft 2 and the outer peripheral surface of the shaft portion 6 b of the cam bolt 6. For this reason, the magnitude | size of the radial direction of the rotor part 21 can be made small enough.

That is, when a part of the discharging means is formed penetrating in the direction of the internal axis of the rotor portion 21, the outer diameter of the rotor portion 21 must be increased to ensure a space for forming the portion. The axial groove 53 which is a part of the discharging means is formed using the inner peripheral surface of the second fitting groove 21b without forming the rotor part 21 so as to penetrate the existing positioning hole 51. Since the discharge passage 56 is formed by using a part of the passage as a passage and further using a cylindrical gap between the inner peripheral surface of the camshaft 2 and the outer peripheral surface of the cam bolt 6, the outer diameter of the rotor portion 21. There is no need to increase the size. Therefore, it is possible to suppress an increase in the size of the entire apparatus.

Moreover, since the inner peripheral surface of the existing second fitting groove 21b, the positioning hole 51, and the camshaft 2 and the cam bolt 6 are used as a part of the discharging means, there is no need to process the passage specially. Manufacturing work is facilitated, and an increase in cost can be suppressed. In particular, the radial groove 52, the axial groove 53, the passage groove 54, the second fitting groove 21b, the positioning hole 51, and the like can be formed together in the mold when the vane rotor 7 is sintered. The forming operation becomes easy.

Furthermore, since the drain hole 57 is formed so as to penetrate along the radial direction passing through the axis of the camshaft 2 by a drill tool or the like, this processing operation is also easy.

Since the passage groove 54 between the axial groove 53 and the positioning hole 51 is formed by cutting out the seating surface 21c on which the seat 6 of the cam bolt 6 is seated from the radial direction, the seating surface 21c is effective. Since a sufficient area can be secured, a decrease in the fastening force of the cam bolt 6 can be suppressed.

Since each advance side oil groove 19 is formed along the radial direction on the inner end face of the rear plate 13, it is not necessary to increase the axial length, and the axial length of the apparatus can also be reduced.

Further, the oil discharged to the outside from the drain hole 57 is received by the bottom surface of the drain groove 58 and is guided as it is toward the flange portion 2d of the camshaft 2, and from here to the outside through the outer surface of the flange portion 2d. Discharged. That is, the oil flowing out from the drain hole 57 is guided by the drain groove 58 in a direction sufficiently away from the timing pulley 1 in the axial direction of the camshaft 2, and further adheres to the outer surface of the flange portion 2d. The oil adhering to the outer surface of the flange portion 2d is scattered in an annular shape from the outer peripheral edge of the flange portion 2 to the outside by the centrifugal force when the camshaft 2 rotates. For this reason, since the discharged oil does not adhere to the timing pulley 1, it is possible to suppress the occurrence of slipping between the gear portions 1 a of the timing pulley 1 and the timing belt.

In this embodiment, in order to unlock the lock pin 30, the hydraulic pressure from the retarded oil chamber 9 and the hydraulic pressure from the advanced oil chamber 10 are used, but only the hydraulic pressure from the retarded oil chamber 9 is used. It is also possible. If this valve timing control device is provided on the exhaust valve side, the oil pressure discharged from the oil pump is supplied to each advance oil chamber 10 at the initial stage of engine start. It is possible to use only the hydraulic pressure in the chamber 10.

Claims

A housing in which a rotational force from the crankshaft is transmitted and a hydraulic oil chamber is provided inside;
A bolt insertion hole, fixed to one end of the camshaft by a cam bolt inserted into the bolt insertion hole, and accommodated in the housing so as to be relatively rotatable; A vane rotor that divides into an advance working chamber;
A lock hole formed in the inner end surface of the housing;
It is movably disposed in a sliding hole formed in the inner axial direction of the vane rotor, and an axial tip is engaged with and disengaged from the lock hole to lock the relative rotational position of the vane rotor with respect to the housing, or A locking member for releasing the lock;
An urging member disposed in a back pressure chamber provided on the front side opposite to the camshaft of the sliding hole, and urging the lock member toward the lock hole;
A communication path provided in the vane rotor and communicating with the bolt insertion hole and the back pressure chamber;
A drain formed between the inner peripheral surface of the bolt insertion hole and the outer peripheral surface of the shaft portion of the cam bolt, with one end communicating with the communication path and the other end formed on the camshaft. An annular passage communicating with the hole;
A valve timing control apparatus for an internal combustion engine, comprising:
The valve timing control apparatus for an internal combustion engine according to claim 1,
The communication passage is formed in a radial direction on a seating surface on which the head of the cam bolt on the front end surface of the vane rotor is seated, and one end communicates with the back pressure chamber and the other end communicates with the annular passage. A valve timing control device for an internal combustion engine, comprising: a communication groove.
The valve timing control device for an internal combustion engine according to claim 2,
The communication path is formed in a radial direction on the front end surface of the vane rotor, and has one end communicating with the back pressure chamber and the other end communicating with the first communication groove. An internal combustion engine valve timing control device.
The valve timing control apparatus for an internal combustion engine according to claim 3,
The valve timing control device for an internal combustion engine, wherein the first communication groove is formed so as to penetrate in the axial direction, and a positioning pin fixed to one end of the camshaft faces the first communication groove.
The valve timing control apparatus for an internal combustion engine according to claim 3,
The first communication groove and the second communication groove are bent in a crank shape in a longitudinal section, and have an inner surface of a front plate that closes a front end opening of a housing body of the housing and a flange shape of a head of the cam bolt. A valve timing control device for an internal combustion engine, wherein the valve timing control device is formed between an inner surface of a seat portion.
The valve timing control apparatus for an internal combustion engine according to claim 1,
The camshaft is formed in the direction of the internal axis of the camshaft, and is formed between a bolt hole through which a cam bolt shaft portion is inserted, and an inner peripheral surface of the bolt hole and an outer peripheral surface of the cam bolt shaft portion. And having one end portion communicating with the annular passage and the other end portion communicating with the drain hole,
The valve timing control device for an internal combustion engine, wherein the discharge passage is formed by a cylindrical gap formed between an inner peripheral surface of the bolt hole and an outer peripheral surface of a shaft portion of the cam bolt.
The valve timing control apparatus for an internal combustion engine according to claim 6,
The valve timing control device for an internal combustion engine, wherein the bolt hole is formed at a position facing the bolt insertion hole of the vane rotor from an axial direction.
The valve timing control apparatus for an internal combustion engine according to claim 7,
A cylindrical portion extending in the axial direction along the outer peripheral surface of the camshaft is provided at the opening edge of the insertion hole into which the camshaft of the housing is inserted, and a groove portion is formed on the inner peripheral surface of the cylindrical portion. Formed,
The valve timing control device for an internal combustion engine, wherein the drain hole is formed from the discharge passage side toward a radially outer side of the camshaft, and an outer end opening faces the groove portion.
The valve timing control apparatus for an internal combustion engine according to claim 1,
A retard passage and an advance passage are formed in the camshaft, and the vane rotor includes one of the retard passage, the advance passage, and one of the retard working chamber and the advance working chamber. A first oil passage for communication is formed;
A valve for an internal combustion engine, wherein the housing is formed with a second oil passage for communicating the other of the retard passage and the advance passage with the other of the retard working chamber and the advance working chamber. Timing control device.