CN114846224A - Valve timing control device for internal combustion engine - Google Patents

Abstract

A valve timing control device for an internal combustion engine is provided with a lock pin receiving hole (26) provided in a large diameter portion (15A) of a vane rotor (9), lock pins (28, 29) arranged inside the lock pin receiving hole, and a lock hole (24) provided in the inner side surface of a front plate (13), wherein an opening groove (13A) having a circular-arc concave shape is provided on the inner peripheral edge of a through hole (13A) provided in the center of the front plate, and a part of an opening portion (26c) having a conical shape with an enlarged diameter provided on the side of the other end portion (26b) of the lock pin receiving hole overlaps with the opening groove in the direction of the rotation axis of the vane rotor, whereby the opening groove and the lock pin receiving hole are brought into a communicating state in the axial direction. With these configurations, the valve timing control accuracy can be improved by improving the drainage of air or hydraulic oil from the lock pin accommodating hole to suppress a decrease in the movement speed of the lock pin.

Description

Valve timing control device for internal combustion engine

technical field

The present invention relates to a valve timing control device for a hydraulic internal combustion engine.

Background technique

As a conventional valve timing control device for an internal combustion engine, there is, for example, a valve timing control device for a vane type internal combustion engine described in Patent Document 1 below.

In this valve timing control device, the wide vane of the vane rotor that is relatively rotatably arranged inside the casing has a lock pin housing hole formed therethrough in the direction of the rotation axis. A lock pin is slidably accommodated in the lock pin accommodating hole. On the other hand, a locking hole into which the front end portion of the locking pin can be inserted is provided on the inner side surface of the wall portion on the rear end side of the housing. A communication groove that communicates the opening on the rear end side of the lock pin accommodating hole and the through hole provided in the center of the front plate is formed on the end surface of the wide blade on the front plate side provided on the front end side of the casing. The communication groove discharges the back pressure accompanying the movement of the lock pin, or the hydraulic oil or air leaking from between the outer peripheral surface of the lock pin and the inner peripheral surface of the lock pin housing hole.

prior art literature

Patent Literature

Patent Document 1: WO2018/101155

SUMMARY OF THE INVENTION

The problem to be solved by the invention

However, the communication groove described in Patent Document 1 extends radially inward from the opening edge of the rear end portion of the lock pin accommodating hole, and has a crank shape in which the front end portion and the through hole of the front plate communicate with each other in the axial direction. Therefore, in this communication groove, the entire passage length is increased, and the flow resistance of the hydraulic oil and the like is increased, and the discharge performance of the hydraulic oil is reduced, and there is a possibility that the hydraulic oil may stay in the passage. As a result, the moving speed of the lock pin in the backward direction decreases, and the control accuracy of the valve timing may deteriorate.

The present invention has been made in view of the above-mentioned conventional technical problems, and an object of the present invention is to suppress a decrease in the moving speed of the lock pin by improving the dischargeability of air or hydraulic oil from the lock pin accommodating hole, thereby realizing the improvement of the valve timing control accuracy. improve.

technical solutions for problem solving

As an aspect of this invention, it is characterized in that the housing has an opening part open to the outside at a position on the opposite side of the locking recessed part in the axial direction,

The lock pin accommodating hole has an opening for releasing back pressure at an end on the other end side in the axial direction of the lock pin,

Among the openings, the innermost portion in the radial direction centered on the rotational axis of the vane rotor overlaps the opening portion in the rotational axis direction of the vane rotor.

Invention effect

According to the present invention, it is possible to improve the dischargeability of air or hydraulic oil from the lock pin housing hole, and to suppress a decrease in the movement speed of the lock pin.

Description of drawings

FIG. 1 is an overall configuration diagram showing a first embodiment of a valve timing control device according to the present invention.

FIG. 2 is an exploded perspective view of each component of the valve timing control device according to the present embodiment.

FIG. 3 is a cross-sectional view taken along line A-A in FIG. 1 , showing a state in which the vane rotor of the present embodiment is rotated to the position of the most advanced angle phase.

FIG. 4 is a cross-sectional view taken along line A-A in FIG. 1 , showing a state in which the same vane rotor is held at a rotational position of an intermediate phase.

FIG. 5 is a cross-sectional view taken along line A-A in FIG. 1 , showing a state in which the same vane rotor is rotated to the position of the most retarded angle phase.

FIG. 6 is a cross-sectional view taken along the line B-B in FIG. 4 .

FIG. 7(A) is a view taken along arrow C in FIG. 6 , and FIG. 7(B) is an enlarged view of part D in FIG. 7(A).

FIG. 8 is an enlarged view schematically showing part E of FIG. 6 .

FIG. 9 is a cross-sectional view showing the lock mechanism when the vane rotor is located at the relative rotational position of the most advanced angle.

10 is a cross-sectional view showing the lock mechanism when the vane rotor is further rotated to the retarded angle side.

11 is a cross-sectional view showing the lock mechanism when the vane rotor is further rotated to the retarded angle side.

12 is a cross-sectional view showing the lock mechanism when the vane rotor is further rotated to the retarded angle side and is located at the intermediate lock position.

FIG. 13 is an enlarged view of part D of FIG. 7(A) showing the second embodiment of the present invention.

FIG. 14 is an enlarged view of part D of FIG. 7(A) showing the third embodiment of the present invention.

Detailed ways

Hereinafter, each embodiment in which the valve timing control device of the internal combustion engine of the present invention is applied to, for example, the exhaust valve side will be described based on the drawings.

[First Embodiment]

1 is an overall configuration diagram showing a first embodiment of a valve timing control device according to the present invention, FIG. 2 is an exploded perspective view of each component of the valve timing control device according to the present embodiment, and FIG. 3 is a diagram showing the present embodiment. 1 is a cross-sectional view taken along the line A-A of FIG. 1 in a state where the vane rotor is rotated to the position of the most advanced angle phase, FIG. 4 is a cross-sectional view taken along the line A-A of FIG. A cross-sectional view taken along the line A-A in FIG. 1 , showing the state where the rotor is rotated to the most retarded angular phase position.

The valve timing control device includes a sprocket 1 , which is a drive rotating body that is rotatably driven by a crankshaft of an internal combustion engine via a timing chain, a camshaft 2 on the exhaust valve side that is provided so as to be relatively rotatable with respect to the sprocket 1 , and is arranged on the The sprocket 1 and the camshaft 2 are provided with a phase change mechanism 3 that switches the relative rotational phases of the two 1 and 2 , and a first hydraulic circuit 4 that operates the phase change mechanism 3 .

The sprocket 1 includes an annular sprocket body 5 and a gear portion 6 integrally provided at an outer peripheral end portion of the sprocket body 5 and wound around a timing chain.

The sprocket main body 5 is integrally formed of a high-hardness steel material, and is configured as a rear plate that closes a rear end opening of a casing to be described later. In addition, the sprocket main body 5 has a support hole 5a that rotatably supports the sprocket main body 5 on the outer periphery of the vane rotor 9 to be described later, and is formed in the center. In addition, a plurality of (four in the present embodiment) female screw holes 5 b are formed at predetermined positions in the circumferential direction of the outer peripheral portion of the sprocket main body 5 .

The camshaft 2 on the exhaust valve side is rotatably supported by a cylinder head (not shown) via a cam bearing, and a plurality of drives for opening the exhaust valve, which is an internal combustion engine valve, are integrally fixed on the outer peripheral surface at axial positions. cam. In addition, the camshaft 2 is formed with a female screw hole 2b into which the cam bolt 8 is screwed in the inner axial center direction of one end portion 2a in the rotation axis direction.

As shown in FIGS. 1 to 3 , the phase changing mechanism 3 includes a housing 7 integrally bolted with the sprocket 1 , and is relatively rotatably accommodated in a cam bolt 8 that is screwed into the female screw hole 2 b of the camshaft 2 to be fixed and relatively rotatable. The vane rotor 9 , which is a driven rotating body in the casing 7 , and the vane rotor 9 are separated from the vane rotor 9 by a plurality of (four in this embodiment) shoes 10 a to 10 d provided on the inner peripheral surface of the casing main body 7 a , which will be described later. The open operation chambers are a plurality of (four in the present embodiment) retarded angle hydraulic chambers 11a to 11d and advanced angle hydraulic chambers 12a to 12d.

The casing 7 includes a casing main body 7a formed into a cylindrical shape from a sintered metal material obtained by compressing and sintering metal powder, a front plate 13 which is a plate member that closes the front end opening in the rotation axis direction of the casing main body 7a, and the casing main body 7a. The rear end opening of the sprocket body 5 is blocked as a rear plate.

The four shoe pieces 10a to 10d protruding inward are integrally provided in the casing main body 7a at substantially equal intervals in the circumferential direction of the inner peripheral surface. Each of the shoes 10a to 10d is formed in a substantially trapezoidal shape when viewed from the front, and a bolt insertion hole 10e is formed through the inside of each in the direction of the rotation axis of the housing 7 . In addition, the circumferential width of the two adjacent first and second shoe blocks 10a and 10b is formed to be larger than that of the other third and fourth shoe blocks 10c and 10d. The first shoe 10a is integrally provided with a first convex wall 10f that is in contact with the first blade 16a from the right rotation direction on the left side in FIG. 3 . The second shoe 10b is integrally provided with a second convex wall 10g that is in contact with the third blade 16c from the left rotation direction on the right side surface in FIG. 3 .

Moreover, the groove|channel 7c for positioning is provided in the outer peripheral surface of the 1st shoe block 10a of the housing main body 7a. In this groove 7c, the pin 5c for positioning provided in the sprocket main body 5 is inserted from the rotation axis direction, and the casing main body 7a and the sprocket main body 5 are positioned.

The front plate 13 is formed into a disk shape by press-molding, for example, an iron-based metal plate, and a through hole 13a is formed in the inner peripheral portion, that is, at the center position. In addition, the front plate 13 has a plurality of (four in the present embodiment) bolt insertion holes 13b formed therethrough at equal intervals in the circumferential direction of the outer peripheral portion. An annular counterbore portion 13c is formed at the front end opening edge of each bolt insertion hole 13b, respectively.

In addition, two first and second open grooves 13A and 13B as open portions (recesses) are provided on the inner peripheral surface of the through hole 13a. The first and second open grooves 13A and 13B are arranged at approximately 180° positions in the circumferential direction of the through hole 13a so as to face each other, and are respectively formed in arcuate concave shapes that are long in the circumferential direction. That is, each of the open grooves 13A and 13B is a circular-arc groove-shaped cutout from the inner peripheral surface of the through hole 13a toward the outer side in the radial direction of the front plate 13 .

The casing main body 7 a , the front plate 13 , and the sprocket main body 5 are fastened and fixed by a plurality of (four in the present embodiment) bolts 14 . That is, each bolt 14 is inserted into each bolt insertion hole 13b and each bolt insertion hole 10e, and is screwed into each female screw hole 5b to integrally couple the three 5, 7a, and 13 in the rotation axis direction.

The vane rotor 9 is integrally formed of a sintered metal material obtained by compressing and sintering metal powder, and has a rotor 15 fixed to one end 2 a of the camshaft 2 by a cam bolt 8 , and a rotor 15 radially outward from the outer peripheral surface of the rotor 15 . The plurality of (four in the present embodiment) first to fourth blades 16a to 16d protrudingly provided at equal intervals of approximately 90° in the circumferential direction.

The rotor 15 is formed in a substantially cylindrical shape long in the direction of the rotation axis, and a cylindrical protruding portion 15a having a stepped small diameter is integrally provided at the front end portion on the side of the front plate 13 . In addition, the rotor 15 is integrally provided with a cylindrical support portion 15b having a stepped small diameter extending in the direction of the camshaft 2 at the rear end portion on the side of the sprocket 1 .

In addition, the rotor 15 is provided with a larger-diameter fitting hole 15c into which the cam bolt 8 and the passage configuration portion 37 described later are fitted from the front end side toward the inner axial direction. A cam bolt insertion hole 15e through which the shaft portion 8b of the cam bolt 8 is inserted is formed in the bottom wall portion 15d on the support portion 15b side of the fitting hole 15c.

The protruding portion 15a is inserted in a state in which the outer peripheral surface does not contact the inner peripheral surface of the through hole 13a of the front plate 13, and a tapered surface 15f whose diameter is enlarged outward is formed on the distal inner peripheral surface.

In the support portion 15b, the outer peripheral portion on the front plate 13 side in the rotation axis direction is bearing-fitted into the support hole 5a of the sprocket main body 5, and the entire sprocket 1 is rotatably supported by the bearing.

Also, a coil spring 40 that biases the vane rotor 9 to relatively rotate toward the position shown in FIG. 3 , that is, the advance angle side, is disposed on the outer periphery of the front end portion on the camshaft 2 side of the support portion 15b. The inner end portion 40a of the coil spring 40 in the winding direction is bent inward and locked in the circumferential direction by the locking groove 15g which is a cutout formed in the support portion 15b. In addition, the outer end portion of the coil spring 40 in the winding direction is bent outward, and is locked to a stopper pin 41 attached to the outer side surface of the sprocket main body 5 . It should be noted that the coil spring 40 is supported by a support pin 42 , and the middle portion of the support pin 42 is fixed to the outer side surface of the sprocket main body 5 .

In addition, a fitting groove 15h into which the front end portion of one end portion 2a of the camshaft 2 is fitted from the rotation axis direction is provided at a position opposite to the inner bottom surface of the bottom wall portion 15d.

In the rotor 15, as shown in FIG. 3, two first and second large diameters are integrally provided on the side portions in the circumferential direction of the first vane 16a and the third vane 16c, that is, at positions approximately 180° in the radial direction. Sections 15A, 15B. The large diameter portions 15A and 15B are arranged to be point-symmetrical about the rotation axis X of the rotor 15, and are formed in a substantially symmetrical shape. In addition, for the large diameter portions 15A and 15B, the lengths in the circumferential direction including the first vane 16a described later are set to the first and fourth shoe blocks 10a and 10d and the second shoe blocks, The circumferential length between the third shoe blocks 10b and 10c is about 1/2. Moreover, the width length W of each radial direction of each large diameter part 15A, 15B is set to about 1/2 of the radial width direction length of each hydraulic chamber 11a-12d.

The blades 16a to 16b are respectively arranged between the shoe blocks 10a to 10d, and first and second large blades are integrally provided on the sides of the first blade 16a and the third blade 16c located at a position symmetrical to the first blade 16a. Diameter parts 15A, 15B. The second vane 16b and the fourth vane 16d protrude radially outward from the outer peripheral surface of the rotor 15, and are formed to have the same outer diameter as the first and third vanes 16a and 16c.

Sealing members 17a and 17b for sealing between the inner surface of the casing main body 7a and the outer peripheral surface of the base of the rotor 15 are provided on the front end surfaces of the blades 16a to 16d and the shoes 10a to 10d, respectively.

In addition, when the vane rotor 9 relatively rotates toward the advanced angle side, as shown in FIG. 3 , one side surface of the first vane 16a abuts on the opposite side surface of the first convex wall 10f of the first shoe block 10a facing each other and is restricted Rotational position on the maximum advance angle side. In addition, when the vane rotor 9 is relatively rotated toward the retarded angle side, as shown in FIG. 5 , one side surface of the third vane 16c abuts against the opposite side surface of the second convex wall 10g of the opposing second shoe 10b and restrains Rotational position on the side of the largest lag angle.

At this time, the other blades 16b and 16d and the opposing shoe blocks 10b and 10c are not in contact with each other and are in a separated state. Therefore, the contact accuracy between the vane rotor 9 and the shoes 10a and 10b is improved, and the supply speed of the hydraulic oil to the retarded angle hydraulic chambers 11a to 11d or the advanced angle hydraulic chambers 12a to 12d is increased, and the forward and reverse directions of the vane rotor 9 are increased. Rotational responsiveness becomes high.

The retard hydraulic chambers 11 a to 11 d and the advanced hydraulic chambers 12 a to 12 d correspond to the first hydraulic pressure via the four first communication holes 11 e and the second communication holes 12 e formed in the rotor 15 in a substantially radial shape, respectively. Loop 4 is connected.

The first hydraulic circuit 4 basically selectively supplies or discharges hydraulic oil (hydraulic pressure) to or from the respective retarded angle and advanced angle hydraulic chambers 11 and 12, and as shown in FIG. A retard oil passage 18 for supplying and discharging hydraulic pressure from 11a to 11d, and an advanced angle oil passage 19 for supplying and discharging hydraulic pressure to each of the advanced angle hydraulic chambers 12a to 12d via the second communication hole 12e, and selectively supplying the oil passages 18 and 19 An oil pump 20 , which is a hydraulic supply source of hydraulic oil, and a first electromagnetic switching valve 21 that switches the flow paths of the retarded angle oil passage 18 and the advanced angle oil passage 19 according to the operating state of the internal combustion engine. The oil pump 20 is a general oil pump such as a cycloid pump that is rotationally driven by a crankshaft of an internal combustion engine.

One end portion of each of the retarded angle oil passage 18 and the advanced angle oil passage 19 is connected to a passage hole of the first electromagnetic switching valve 21 . On the other hand, the other end side communicates with each of the retarded angle hydraulic chambers 11a to 11d and each of the advanced angle hydraulic chambers 12a to 12d via the passage configuration portion 37 and the like. That is, the other end sides of the oil passages 18 and 19 pass through the passage portions 18 a and 19 a and the passage portions 18 a and 19 a which are formed in parallel in the axial direction in the passage constituting portion 37 inserted and held in the fitting hole 15 c of the rotor 15 of the vane rotor 9 . The first and second communication holes 11e and 12e communicate with the retardation hydraulic chambers 11a to 11d and the advanced hydraulic chambers 12a to 12d, respectively.

Moreover, a part of the 1st hydraulic circuit 4 is connected to the 2nd hydraulic circuit 32 which supplies the hydraulic pressure which releases the lock of the lock mechanism mentioned later.

As for the passage structure part 37, the outer edge part is fixed to the chain cover which is not shown in figure, and is comprised as a non-rotating part. In addition to the passage portions 18a and 19a, the passage constituting portion 37 is formed with a lock release passage portion 32a of the second hydraulic circuit 32 that releases the lock of the lock mechanism described later in the inner axial direction.

As shown in FIG. 1 , the first electromagnetic switching valve 21 is a three-position, four-way proportional valve, and a spool valve provided in the valve body is moved in the axial direction by a control unit (ECU) not shown. The spool valve communicates the discharge passage 20a of the oil pump 20 with any one of the oil passages 18 and 19, and at the same time communicates the other oil passages 18 and 19 with the discharge passage 22 in accordance with the movement position thereof. In addition, when the internal combustion engine is stopped, etc., the spool valve is held at the intermediate moving position in the axial direction, and the communication between the oil passages 18 and 19 and the discharge passage 20a and the discharge passage 22 are all cut off, and the hydraulic oil is sealed in the respective hydraulic chambers 11 and 12. .

The suction passage 20 b of the oil pump 20 and the discharge passage 22 communicate with each other in the oil pan 23 . In addition, on the downstream side of the discharge passage 20a of the oil pump 20, a main oil passage M/G for supplying lubricating oil to a sliding part of the internal combustion engine and the like communicates with each other. A filter 50 is provided between the discharge passage 20a and the M/G. Furthermore, the oil pump 20 is provided with a flow rate control valve 51 which discharges the excess hydraulic oil discharged from the discharge passage 20a to the oil pan 23 and controls the flow rate to an appropriate flow rate.

In the case of the ECU, the computer is based on a crank angle sensor (not shown in the internal combustion engine rotation speed detection), an air flow meter, an internal combustion engine water temperature sensor, an internal combustion engine temperature sensor, a throttle valve opening sensor, and a cam for detecting the current rotational phase of the camshaft 2. Information signals from various sensors such as angle sensors are used to control the operation of the internal combustion engine. In addition, the ECU controls the movement of the respective spool valves by outputting control pulse currents to the respective coils of the first electromagnetic switching valve 21 or the second electromagnetic switching valve 36 described later, thereby switching the passages.

In addition, in this embodiment, the vane rotor 9 is held between the rotational position on the most advanced angle side (the position in FIG. 3 ) and the rotational position on the most retarded angle side (the position in FIG. 5 ) with respect to the casing 7 . Locking mechanism in intermediate rotational position (position in Figure 4).

6 is a sectional view taken along line B-B of FIG. 4 , FIG. 7(A) is a view taken along line C of FIG. 6 , FIG. 7(B) is an enlarged view of part D of FIG. 7(A) , and FIG. 8 is a schematic view of FIG. FIG. 9 is an enlarged view of the part E, FIG. 9 is a cross-sectional view showing the locking mechanism when the vane rotor is at the relative rotational position of the most advanced angle, and FIG. 10 is a cross-sectional view showing the locking mechanism when the vane rotor is further rotated to the retarded angle side, 11 is a cross-sectional view showing the locking mechanism when the vane rotor is further rotated to the retarded angle side, and FIG. 12 is a cross-sectional view showing the locking mechanism when the vane rotor is further rotated to the retarded angle side and is located at the intermediate locking position.

As shown in FIGS. 6 and 9 to 12 , the locking mechanism is composed of two mechanisms, and mainly includes two first and second locking recesses provided at predetermined positions in the circumferential direction of the inner side surface 5d of the sprocket main body 5 , ie, two locks. The holes 24 and 25, the first and second lock pin receiving holes 26 and 27 formed through each of the two large-diameter portions 15A and 15B of the vane rotor 9 in the direction of the rotation axis are slidably provided in the first and second lock pin receiving holes 26 and 27. 2. The second locking pin receiving holes 26, 27 and the two locking members that can be inserted and withdrawn (inserted and withdrawn) in the respective locking holes 24, 25, namely the first and second locking pins 28, 29, are provided in each locking pin. The first and second springs 30 and 31 that urge the lock pins 28 and 29 in the axial direction of the receiving holes 26 and 27 in the direction of the lock holes 24 and 25 and the first and second springs 30 and 31 that overcome the lock pins 28 and 29 The second hydraulic circuit 32 (refer to FIG. 1 ) is configured by the elastic force of the respective springs 30 and 31 to move backward with respect to the respective lock holes 24 and 25 to release the inserted state.

The first locking hole 24 is formed in the shape of an arc long hole extending in the circumferential direction of the sprocket main body 5, and is formed on the inner side surface 5d at a relative rotational position approximately in the middle of the most retarded angle side and the most advanced angle side of the vane rotor 9. . In addition, the first lock hole 24 is formed in a three-step step shape with the inner side surface 5d of the bottom surface as the uppermost stage and decreasing in order from the advance angle side to the retard angle side, which serves as a guide mechanism (ratchet mechanism).

That is, the inner surface 5d of the sprocket main body 5 is the uppermost stage, and the first bottom surface 24a on the advanced angle side and the second bottom surface 24b on the retarded angle side are formed in a stepped shape in order. The first stepped surface 24c on the side of the first bottom surface 24a is a wall surface that stands vertically. Moreover, the 2nd step surface 24d on the side of the 2nd bottom surface 24b also becomes the wall surface which stood up vertically.

Therefore, when the front end portion 28a of the first lock pin 28 inserted into the bottom surfaces 24a and 24b moves downward in a stepwise manner on the bottom surfaces 24a to 24b in order to the retarded angle side, the first and second steps pass through the first and second steps. The surfaces 24c and 24d restrict movement in the opposite direction, that is, movement in the advance angle direction. Therefore, each bottom surface 24a, 24b functions as a one-way clutch (ratchet). In addition, the further movement of the first lock pin 28 in the advance angle direction is restricted when the side edge of the front end portion 28a comes into contact with the third stepped surface 24e which is circumferentially adjacent to the second stepped surface 24d. Opposite up.

As also shown in FIG. 2 , the second locking hole 25 is arranged at a position about 180° in the circumferential direction of the inner side surface 5d of the sprocket body 5 from the first locking hole 24 , and is formed on the most retarded angle side and the most retarded angle side of the vane rotor 9 . The relative rotational position about the middle of the advance angle side. In addition, the second lock hole 25 is formed in a circular shape in which the inner diameter of the bottom surface 25 a , that is, the inner diameter of the inner peripheral surface 25 b is slightly larger than the outer diameter of the front end portion 29 a of the second lock pin 29 . It should be noted that the depth of the second locking hole 25 from the inner surface 5d to the bottom surface 25a is approximately the same as the depth from the inner surface 5d to the second bottom surface 24b of the first locking hole 24 .

The relationship between the relative formation positions of the first and second locking holes 24 and 25 is shown in FIGS. 9 to 12 . That is, as shown in FIGS. 9 to 11 , the front end portion 28a of the first lock pin 28 is stepped from the inner surface 5d of the sprocket body 5 to the first bottom surface 24a and the second bottom surface 24b of the first lock hole 24 in a stepped manner. In the connected and sliding state, the second lock pin 29 is in a state in which the front end surface of the front end portion 29 a has not yet abutted on the inner surface 5 d of the sprocket main body 5 . After that, as shown in FIG. 12 , when the front end portion 28 a of the first lock pin 28 moves slightly toward the retarded angle side on the second bottom surface 24 b and comes into contact with the third stepped surface 24 e , the front end portion of the second lock pin 29 29a enters the second locking hole 25 and abuts against the bottom surface 25a.

At this time, the inner peripheral edge of the front end portion 28a of the first lock pin 28 is in contact with the third stepped surface 24e in the circumferential direction. On the other hand, the front end portion 29 a of the second lock pin 29 is in contact with the inner end edge of the inner peripheral surface 25 b of the second lock hole 25 . Accordingly, the vane rotor 9 is restricted from relative rotation in the advanced angle direction and the retarded angle direction by the first lock pin 28 and the second lock pin 29, and is held at an intermediate position between the most advanced angle and the most retarded angle.

In short, as the vane rotor 9 relatively rotates from the predetermined advanced angle side position to the retarded angle side position, the first lock pin 28 is inserted into and abutted against the first bottom surface 24a and the second bottom surface 24b in order from the inner surface 5d, and then, The second locking pin 29 is inserted into and abutted against the bottom surface 25 a of the second locking hole 25 . As a result, the entire vane rotor 9 rotates relatively in the retarded angle direction while the rotation in the retarded angle direction is restricted by the two-stage ratcheting action, and is finally held at an intermediate phase position between the most retarded angle phase and the most advanced angle phase.

As shown in FIGS. 6 and 8 to 12 , the first and second lock pin accommodating holes 26 and 27 are respectively formed from one end 26 a and 27 a on the sprocket main body 5 side to the other end 26 b , 27 a on the front plate 13 side. The inner diameter of the sliding portion in the vicinity of 27b is uniform and the same.

In addition, openings 26c and 27c are respectively provided in the first and second lock pin accommodation holes 26 and 27 on the other end parts 26b and 27b sides. As shown in FIG. 8 , each of the openings 26 c and 27 c is formed in a conical groove shape (mortar shape) that expands in diameter in the direction of the front plate 13 . The inner side of the block is in a state of being blocked. However, in each of the openings 26c and 27c, the radially innermost parts 26d and 27d overlap the first and second open grooves 13A and 13B in the rotation axis direction of the vane rotor 9 . That is, the inner parts 26d and 27d communicate with the corresponding first and second open grooves 13A and 13B in the rotation axis direction.

Therefore, the respective lock pin accommodation holes 26 and 27 are opened to the outside through the respective openings 26c and 27c and the respective open grooves 13A and 13B. In addition, each of these open grooves 13A and 13B and each of the openings 26c and 27c function as breathing holes. Therefore, the respective lock pins 28 and 29 can smoothly slide in the respective lock pin accommodation holes 26 and 27 . It should be noted that the inner portions 26d and 27d are maintained in a state of always communicating with the respective open grooves 13A and 13B at any relative rotational position of the vane rotor 9 .

As also shown in FIG. 9 , the first and second lock pins 28 and 29 are formed so that the outer diameter of each of the front end portions 28 a and 29 a is slightly smaller than the rear end portion side. First and second pressure receiving chambers 33 a and 33 b are formed between the outer peripheries of the respective front end portions 28 a and 29 a and the respective lock pin accommodation holes 26 and 27 , respectively.

Each front end portion 28a, 29a is formed in a flat surface shape in which each front end surface and each bottom surface 24a, 24b of the first lock hole 24 can be brought into contact with each other.

The first and second lock pins 28 and 29 are formed with spring accommodation grooves 28e and 29e for accommodating the first and second springs 30 and 31 along the axial direction in rear end portions other than the respective front end portions 28a and 29a.

As shown in FIGS. 1 and 6 , the second hydraulic circuit 32 is provided inside the rotor 15 with first and second release oil holes that communicate the first and second pressure receiving chambers 33 a and 33 b and the lock release passage portion 32 a 34a, 34b. The first and second release oil holes 34a and 34b communicate with the lock release passage portion 32a via an oil chamber 35 formed between the front end surface of the passage configuration portion 37 and the fitting hole 15c of the rotor 15 .

The lock release passage portion 32 a supplies hydraulic pressure through a supply passage 35 a branched from the discharge passage 20 a of the oil pump 20 , and discharges hydraulic oil through a discharge passage 35 b branched from the discharge passage 22 . Further, between the lock release passage portion 32a and the supply/discharge passages 35a and 35b, a second electromagnetic switching valve, which is a second control valve, is provided for selectively switching the lock release passage portion 32a and the passages 35a and 35b according to the state of the internal combustion engine. 36.

The first and second locking pins 28, 29 overcome the elastic forces of the respective springs 30, 31 from the first and second locking holes 24, 29 by the hydraulic pressures supplied to the inside of the first pressure chamber 33a and the second pressure chamber 33b, respectively. 25 retreats to release the respective inserted states.

The passage constituting portion 37 has a plurality of annular shape (in the present embodiment, a plurality of annular portions (in the present embodiment) formed at the front and rear positions in the axial direction of the outer peripheral surface, and the distal end portion formed in a columnar shape is inserted through the fitting hole 15c. Four annular seal members 39 for sealing between the respective opening ends of the passage portions 18a, 19a and the unlocking passage portion 32a are fitted and fixed to the four fitting grooves, respectively.

The second electromagnetic switching valve 36 is a proportional valve of three-position four-way, and uses a spool valve to release the lock release passage portion 32a and the supply, The discharge passages 35a and 35b are appropriately selectively communicated, and the unlock passage portion 32a and the discharge passage 22 are communicated with each other.

Hereinafter, the operation of the present embodiment will be described based on the drawings.

[Motion control after a short stop]

First, when the internal combustion engine is stopped by turning off the ignition switch after the vehicle normally travels, the driving of the oil pump 20 is also stopped. Therefore, the supply of hydraulic oil to any one of the hydraulic chambers 11 and 12 is stopped. At this time, the first electromagnetic switching valve 21 is energized from the ECU, the spool valve is maintained at the neutral position, and the communication between the discharge passage 20a and the discharge passage 22 for the passages 18 and 19 is cut off. Thereby, since the hydraulic oil is sealed in each of the hydraulic chambers 11 and 12, the variation of the vane rotor 9 can be suppressed.

After that, when the internal combustion engine is restarted after a short time of maintaining the warm engine state, the vane rotor 9 is held at the rotational phase position on the most advanced angle side shown in FIG. 3 at this time, and the exhaust valve is closed at the time The timing is on the side of the maximum advance angle from the bottom dead center of the piston, so the effective compression ratio decreases. Thereby, the pumping loss is reduced, and the vibration is suppressed to obtain a good startability.

[normal control]

When the internal combustion engine is started and entered into normal operation, the first electromagnetic switching valve 21 is energized from the ECU, for example, the discharge passage 20a of the oil pump 20 communicates with the advance oil passage 19, and the discharge passage 22 communicates with the retard oil passage 18. Therefore, the hydraulic pressure is supplied to each of the advance angle hydraulic chambers 12a to 12d, while the hydraulic pressure is discharged from each of the retarded angle hydraulic chambers 11a to 11d. Therefore, the internal pressure of each of the advance angle hydraulic chambers 12a to 12d rises to become a high pressure, and the hydraulic oil in each of the retarded angle hydraulic chambers 11a to 11d is discharged to become a low pressure.

In addition, the second electromagnetic switching valve 36 is also energized, the discharge passage 22a and the supply passage 35a communicate with each other, and the discharge passage 35b is closed. Therefore, the release hydraulic pressure is supplied from the supply passage 35a to the respective pressure receiving chambers 33a and 33b via the lock release passage portion 32a and the respective release oil holes 34a and 34b. Thereby, each pressure receiving chamber 33a, 3b becomes high pressure, each lock pin 28, 29 moves backward, and each front end part 28a, 29a is pulled out from each lock hole 24, 25. Thereby, the vane rotor 9 can freely rotate relative to the left and right.

Therefore, as shown in FIG. 3 , the vane rotor 9 relatively rotates toward the advance angle side (right rotation direction in the figure) with respect to the casing 7 as the internal pressure of the advance angle hydraulic chambers 12 a to 12 d increases, so that the first vane 16 a Abuts against the first shoe block 10a. Therefore, the vane rotor 9 is held on the most advanced angle side, and the performance of the internal combustion engine according to the operating state, for example, performance such as improved fuel economy, is exhibited.

When the operating state of the internal combustion engine changes, the first electromagnetic switching valve 21 is energized from the ECU, the discharge passage 20a communicates with the retard oil passage 18, and the discharge passage 22 communicates with the advance oil passage 19. Therefore, the hydraulic pressure is supplied to each of the retarded angle hydraulic chambers 11a to 11d, while the hydraulic pressure is discharged from each of the advanced angle hydraulic chambers 12a to 12d. As a result, the internal pressure of each of the retarded angle hydraulic chambers 11a to 11d rises and becomes a high pressure, while the hydraulic oil in each of the advanced angle hydraulic chambers 12a to 12d is discharged to become a low pressure.

In addition, the energization of the second electromagnetic switching valve 36 is continued, the communication between the discharge passage 22a, the supply passage 35a and the unlocking passage portion 32a is maintained, and the communication between the unlocking passage portion 32a and the discharge passage 35b is maintained.

As a result, as shown in FIG. 5 , the vane rotor 9 relatively rotates toward the retarded angle side (leftward rotation direction in the figure) with respect to the casing 7 as the internal pressures of the respective retarded angle hydraulic chambers 11 a to 11 d increase, so that the third vane 16c abuts against the second shoe 10b. Therefore, the vane rotor 9 is held on the most retarded angle side, and functions such as improving the performance of the internal combustion engine, for example, the output, according to the operating state.

In addition, when the ignition switch is turned off to stop the internal combustion engine, the driving of the oil pump 20 is stopped, and the energization of the first electromagnetic switching valve 21 from the ECU is stopped. Thereby, the spool valve is moved in one axial direction by the elastic force of the valve spring, so that the discharge passage 22 and the retard oil passage 18 communicate with each other, and the communication between the discharge passage 20a and the advance oil passage 19 is blocked.

At the same time, the energization to the second electromagnetic switching valve 36 is also stopped and the unlock passage portion 32a and the discharge passage 35b are communicated, so that the hydraulic oil in each of the pressure receiving chambers 33a and 33b is discharged. As a result, as shown in FIGS. 9 to 12 , the respective lock pins 28 and 29 are urged in the advancing and withdrawing direction by the elastic force of the respective springs 30 and 31 .

Furthermore, since the supply of the discharge hydraulic pressure from the oil pump 20 is stopped after the stop of the internal combustion engine, the hydraulic pressure is not supplied to any of the retarded hydraulic chambers 11a to 11d and the advanced hydraulic chambers 12a to 12d. did not rise.

Therefore, the vane rotor 9 is slightly rotated to the retarded angle side by the alternating torque, particularly the negative torque, acting on the camshaft 2 . Thereby, as shown in FIGS. 9 and 10 , the front end portion 28a of the first lock pin 28 is abutted and fitted to the first bottom surface 24a of the first lock hole 24 from the inner surface 5d of the sprocket body 5 . At this time, when a positive torque acts on the vane rotor 9 and rotates to the advance angle side, the front end portion 28a of the first lock pin 28 comes into contact with the first stepped surface 24c of the first bottom surface 24a, and is restricted from moving in the advance angle direction. rotate. At this time, the front end portion 29a of the second lock pin 29 slides slightly toward the retard angle side on the inner side surface 5d.

After that, the vane rotor 9 relatively rotates slightly toward the retard side according to the negative torque acting on the camshaft 2 . Then, as shown in FIG. 11 , the first lock pin 28 moves from the first bottom surface 24a to the second bottom surface 24b so that the front end portion 28a descends step by step and comes into contact therewith. At this time, the outer peripheral edge of the front end portion 28a of the first lock pin 28 is in a state in contact with the second stepped surface 24d. Therefore, even if a positive torque acts and the vane rotor 9 returns to the advance angle side, its rotation is restricted by the first lock pin 28 (ratchet function).

At this time, the front end portion 29a of the second lock pin 29 still slides slightly in the retard angle direction on the inner side surface 5d.

After that, if the negative torque further acts, as shown in FIG. 12 , the vane rotor 9 rotates further toward the retarded angle side. Then, the front end portion 28a of the first lock pin 28 slides in the advance angle direction on the second bottom surface 24b, and the outer peripheral edge abuts on the third stepped surface 24e. Subsequently, the front end portion 29a of the second lock pin 29 enters the second lock hole 25 while sliding on the inner side surface 5d and abuts against the bottom surface 25a, and the outer peripheral edge of the front end portion 29a contacts the inner peripheral surface 25b from the circumferential direction. Abut. As a result, a part of the rotor 15 is held between the first lock pin 28 and the second lock pin 29 .

Therefore, as shown in FIG. 4 , the vane rotor 9 is held at a relative rotational phase position intermediate between the most retarded angle and the most advanced angle by the two locking mechanisms. As a result, each of the exhaust valves is controlled to be on the retarded side ahead of the bottom dead center of the piston in the valve closing timing. Therefore, when the ignition switch is turned on when the internal combustion engine is restarted, the compression ratio of the internal combustion engine is increased, the combustion becomes good, and the startability at the time of cold engine or the like is improved.

That is, since the compression ratio of the internal combustion engine is increased at the restart, the startability is improved due to the reduction of the torque load at the cold start, etc., and the reduction of vibration and the improvement of exhaust emission performance can be achieved.

In addition, the lock mechanism improves the retention of the vane rotor 9 in the intermediate phase position, and the step-shaped ratchet mechanism of the first lock hole 24 inevitably guides and moves the first lock pin 28 only in the retarded angle direction. The reliability and stability of the guiding function are guaranteed.

In addition, in the present embodiment, a part of the openings 26c and 27c formed in the diameter-expanded shape of the other ends 26b and 27b of the first and second lock pin accommodation holes 26 and 27 and the through holes in the front plate 13 The first and second open grooves 13A and 13B included in the 13a are connected linearly in the axial direction. Therefore, the hydraulic oil (lubricating oil), air, etc. flowing into the respective lock pin housing holes 26 and 27 can be quickly discharged to the atmosphere through the respective open grooves 13A and 13B from the respective openings 26c and 27c. As a result, smooth sliding of the respective lock pins 28 and 29 is obtained.

In other words, in the present embodiment, as in the prior art described above, the passage length from the rear end portion of the lock pin accommodating hole to the outside is not long but very short, so that the flow resistance of lubricating oil or air can be reduced, Therefore, they can be quickly discharged to the outside.

In addition, since the formation positions of the respective lock pin accommodation holes 26 and 27 can be made as close as possible to the central direction of the rotation axis of the vane rotor 9, that is, the radially inner side of the vane rotor 9 (large diameter portions 15A and 15B), the The openings 26c and 27c communicate with the fixed open grooves 13A and 13B in the axial direction.

That is, the first and second lock holes 24 and 25 are formed directly on the inner side surface 5d of the sprocket main body 5 without using a hole constituting member having a thickness in the radial direction such as a sleeve or the like. Therefore, the formation position of each of the lock holes 24 and 25 can be brought closer to the rotation center side of the sprocket main body 5 . As a result, the formation positions of the respective lock pin accommodation holes 26 and 27 may be located close to the radially inner side of the large diameter portions 15A and 15B.

Therefore, the openings 26c and 27c and the opening grooves 13A and 13B of the through-hole 13a having a fixed inner diameter of the front plate 13 can be linearly communicated in the axial direction. Therefore, the passage length between the other end portions 26b and 27b of the respective lock pin accommodation holes 26 and 27 and the outside can be sufficiently shortened. Thereby, the lubricating oil, air, etc. in each of the lock pin accommodation holes 26 and 27 can be drained efficiently.

In addition, since each of the openings 26c and 27c is formed in a conical shape with an enlarged diameter on the outside, it is possible to obtain a large open groove 13A even if the lock pin housing holes 26 and 27 are not too close to the radially inner side of the vane rotor 9 . , the passage area between 13B. Thereby, the lubricating oil, air, etc. in each of the lock pin accommodation holes 26 and 27 can be drained efficiently.

In addition, since the inner peripheral surfaces of the openings 26c and 27c have an enlarged diameter conical shape, when the lock pins 28 and 29 move backward in the lock pin accommodation holes 26 and 27, the lubricating oil or air is released due to the Since the space becomes large, lubricating oil and the like are less likely to accumulate in each of the openings 26c and 27c. In particular, since the inner peripheral surface of each of the openings 26c and 27c is formed in an enlarged diameter conical shape, that is, a shape inclined outward, lubricating oil and the like are easily discharged to the outside along the inclined surface.

Furthermore, since each of the openings 26c and 27c has an enlarged diameter conical shape, when the vane rotor 9 is formed by sinter molding, good releasability of the mold can be obtained, and thus the manufacturing operation is facilitated. It should be noted that, when the openings 26c and 27c are formed by cutting, the cutting operation becomes easy.

Further, as described above, the respective lock pin accommodation holes 26 and 27 are arranged at positions where the deviation of the major diameter portions 15A and 15B is radially inward from the center of the radial width W centered on the rotation axis of the vane rotor 9 . . Therefore, the radial distance between each of the retard angle and advance angle hydraulic chambers 11a to 12d and the lock pin accommodation holes 26 and 27 is increased, and the seal width is increased. As a result, it is possible to suppress leakage of the hydraulic fluid from the hydraulic chambers 11a to 12d to the lock pins 28 and 29 .

[Second Embodiment]

FIG. 13 shows a second embodiment of the present invention. The basic structure of the entire device is the same as that of the first embodiment, but the shapes of the openings 26c and 27c of the lock pin accommodation holes 26 and 27 are changed.

That is, each opening part 26c, 27c which the other end part 26b and 27b of each lock pin accommodating hole 26 and 27 has is not a conical shape, but is formed in the disk shape. In each of the openings 26c and 27c, the inner diameter R is formed to be large, and is formed to be larger than the inner diameter of the lock pin accommodation holes 26 and 27. In addition, in each of the openings 26 c and 27 c , the innermost portion in the radial direction overlaps with each of the open grooves 13A and 13B in the rotation axis direction of the vane rotor 9 . Moreover, a part of the outer peripheral part including the said innermost part of each opening part 26c, 27c communicates with the outside in the axial direction via the through-hole 13a and each open groove 13A, 13B.

Therefore, also in this embodiment, the same functions and effects as those in the first embodiment can be obtained.

[Third Embodiment]

14 shows a third embodiment, and the basic structure of the entire apparatus is the same as that of the first embodiment, but the shapes of the openings 26c and 27c of the lock pin accommodation holes 26 and 27 are changed as in the second embodiment.

That is, each opening part 26c, 27c is not formed in particular like 1st, 2nd embodiment, but is formed as a part of the other end part 26b, 27b of each lock pin accommodating hole 26,27. That is, the openings 26c and 27c are formed continuously and integrally with the other end portions 27b and 27b of the respective lock pin accommodation holes 26 and 27 formed radially along the axial direction, and therefore are formed to be uniform with the lock pin accommodation holes 26 and 27 . inner diameter and the same inner diameter.

In addition, in each of the openings 26 c and 27 c , the innermost portion in the radial direction overlaps with each of the open grooves 13A and 13B in the rotation axis direction of the vane rotor 9 . Moreover, a part of the outer peripheral part including the said innermost part of each opening part 26c, 27c communicates with the outside in the axial direction via the through-hole 13a and each open groove 13A, 13B.

Therefore, this embodiment also obtains the same functions and effects as those of the first and second embodiments. In particular, unlike the first and second embodiments, the inner diameters of the openings 26c and 27c are the same as those of the lock pin accommodation holes 26 and 27. Therefore, no special formation is required, and therefore, the manufacturing work is easy.

The basic technical idea of the present invention is to make the formation positions of the lock pin accommodation holes 26 and 27 as close as possible to the inner position in the radial direction serving as the center of the rotation axis of the vane rotor 9 (large diameter portions 15A and 15B). The other end portions 26b and 27b sides of the respective lock pin accommodation holes 26 and 27 are directly communicated with the outside (atmosphere) in the axial direction.

Therefore, in the first and second embodiments, the respective openings 26c and 27c are formed in a conical shape or a disk shape with an enlarged diameter. The object of the present invention can be achieved.

In addition, first and second open grooves 13A, 13B are formed in the inner peripheral surface of the through hole 13a as the open portion of the front plate 13, and this is also for improving the connection between the lock pin housing holes 26, 27 (opening portions 26c, 27c). ) connectivity. That is, the first open grooves 13A and 13B may be discarded, and the through hole 13a itself may be used as an open portion.

Furthermore, in the first and second embodiments, the shapes of the respective openings 26c and 27c are made into a conical shape with an enlarged diameter or a disk shape, but it is not limited to these shapes, and other different shapes such as polygonal triangular shapes may be used. or quadrilateral.

In addition, a part of the openings 26c and 27c only needs to communicate with the through-hole 13a of the front plate 13 in the axial direction. Therefore, for example, a part of the openings 26c and 27c on the through-hole 13a side may simply be formed in an inclined groove shape. .

In addition, in each of the above-described embodiments, the configuration in which two locking mechanisms are provided is shown, but one locking mechanism, that is, one locking pin accommodating hole, or one locking pin and one locking hole may be used.

In addition, in each embodiment, the valve timing control device is applied to the exhaust valve side, but it may be applied not only to the exhaust valve side, but also to the intake valve side or to both.

As the valve timing control device of the internal combustion engine based on the embodiment described above, for example, the valve timing control device of the internal combustion engine of the embodiment described below is also considered.

That is, as a preferable aspect of the present invention, the present invention includes a casing that transmits the rotational force from the crankshaft and has a plurality of operation chambers therein, and a vane rotor that is fixed to the camshaft and that separates the plurality of operation chambers. a plurality of blades; a locking pin accommodating hole, which is provided in the vane rotor; a locking pin, which is slidably arranged inside the locking pin accommodating hole; The axial end of the locking pin is inserted,

The housing has an opening portion open to the outside at a position opposite to the locking recessed portion in the axial direction,

The lock pin accommodating hole has an opening for releasing back pressure at an end on the other end side in the axial direction of the lock pin,

Among the openings, the innermost portion in the radial direction centered on the rotational axis of the vane rotor overlaps the opening portion in the rotational axis direction of the vane rotor.

According to the aspect of the present invention, the opening portion for releasing the back pressure overlaps the opening portion in the axial direction of the lock receiving hole, and the overlapping portion communicates along the axial direction, so that the lubricating oil or air in the locking pin receiving hole is removed from the lock pin receiving hole. The opening portion passes through the opening portion and is discharged to the atmosphere. At this time, the dischargeability of the air etc. which pass through the said opening part improves.

In addition, the opening portion and the opening portion can be communicated in the axial direction because the formation position of the lock pin accommodating hole can be made as close as possible to the center direction of the rotation axis of the vane rotor, that is, radially inward of the vane rotor.

More preferably, the lock pin accommodating hole has the opening portion, and a sliding portion having the same inner diameter as the opening portion and allowing the locking pin to slide, and the opening portion has a larger inner diameter than the sliding portion. An annular groove portion is formed, and a part of the annular groove portion and the open portion overlap in the rotation axis direction of the vane rotor.

According to the aspect of the present invention, even if the annular groove portion does not come too close to the radially inner side of the vane rotor, the area of the passage that communicates with the open portion increases, so that lubricating oil, air, and the like can be sufficiently discharged.

In addition, when the lock pin is pulled out from the lock concave portion in the lock pin housing hole and moves backward, the release space for lubricating oil, air, etc. becomes large, so that the lubricating oil and the like are less likely to accumulate in the opening portion.

More preferably, the annular groove portion is formed in a conical shape, and the radius of one end on the side of the open portion is formed to be larger than the radius of the other end on the side of the sliding portion in the rotation axis direction of the vane rotor. .

According to the aspect of the present invention, since the annular groove portion is formed in a conical shape (a mortar shape) with a wide open portion side, it can be molded together when the vane rotor is formed by, for example, sinter molding, and therefore, the manufacturing operation is facilitated. . In addition, cutting is also easy.

More preferably, the vane rotor is formed by sinter molding, and the inner peripheral surface of the groove portion is formed on an unprocessed conical surface. According to the aspect of the present invention, since the annular groove portion is formed in a conical shape (a mortar shape) with a wide open portion side, the mold releasability during sinter molding of the vane rotor is good, and thus molding processing becomes easy.

More preferably, the casing has a cylindrical shape, and includes a casing body having an opening in at least one axial direction, a plate member that closes one opening of the casing body, and a through hole formed through an inner peripheral portion of the plate member. The inner peripheral edge has the opening portion.

More preferably, the open portion is a recessed portion recessed radially outward in the inner peripheral edge of the through hole of the plate member.

According to the aspect of the present invention, when the plate member is formed by, for example, press molding, the concave portion can be molded together, so that the forming operation of the concave portion becomes easy.

More preferably, the vane rotor includes a rotor fixed to the camshaft, a large-diameter portion provided to extend radially outward from an outer circumference of the rotor, and a large-diameter portion extending radially from the large-diameter portion. The vane provided so as to extend outward, the lock pin receiving hole is provided in the large-diameter portion, and the large-diameter portion communicates with the vane rotor over the entire range of the relative rotation of the vane rotor with respect to the housing. The open portions overlap in the axial direction.

According to the aspect of the present invention, even if the vane rotor rotates relatively, the open portion is covered by the large diameter portion, so that the sealing performance of the side gap is enhanced, and the hydraulic oil in the operating chamber is less likely to leak from the open portion to the outside.

More preferably, the lock pin accommodating hole is provided at a position inward in the radial direction from the center of the radial width of the large-diameter portion relative to the center of the radial width centered on the rotation axis of the vane rotor.

According to the aspect of the present invention, by providing the lock pin housing hole in the large-diameter portion at a position offset toward the rotation center side of the vane rotor, the lock pin can be arranged radially inward as compared with the prior art. Thereby, the sealing width between the operating chamber and the lock pin accommodating hole is increased, and the leakage of the hydraulic oil from the operating chamber can be suppressed.

More preferably, the locking recess is formed directly on the inner surface of the housing.

According to the aspect of the present invention, since the lock recessed portion is directly formed in the housing without using the sleeve or the like, it is not necessary to consider the radial thickness width of the sleeve or the like. Therefore, since the formation position of the lock recessed portion, in other words, the formation position of the lock pin housing hole, can be made close to the rotation axis of the vane rotor having the radial width of the large diameter portion, a part of the opening portion can be easily overlapped with the opening portion.

More preferably, the annular groove portion has a different shape in cross-sectional shape in the direction perpendicular to the axis.

More preferably, the annular groove portion is formed in a stepped disc shape having a diameter larger than an inner diameter of the sliding portion of the lock pin accommodating hole.

As another preferred mode, a valve timing control device for an internal combustion engine includes: a casing that transmits rotational force from a crankshaft and has a plurality of operating chambers therein; a vane rotor that is fixed to the camshaft and has a A plurality of blades separated from the plurality of operation chambers respectively; a locking pin receiving hole, which is arranged in the blade rotor; a locking pin, which is slidably arranged inside the locking pin receiving hole; a locking recess, which is arranged in the The housing is capable of inserting one end portion in the axial direction of the locking pin; the opening portion is provided in the housing and penetrates in the direction of the rotation axis of the housing to communicate the inside and the outside of the housing ,

In the lock pin housing hole, a part of the opening part provided on the other end side in the axial direction of the lock pin is located close to the opening part over the entire range of relative rotation between the casing and the vane rotor. The axes overlap upwards.

Description of reference numerals

1 sprocket

2 camshaft

3 Phase change mechanism

4 The first hydraulic circuit

5 Sprocket body

7 shell

9 blade rotor

10a～10d 1st to 4th hoof

11a～11d Lag angle hydraulic chamber

12a～12d Advance angle hydraulic chamber

13 Front plate (housing)

13a Through hole

13A·13B First and second open grooves (open part)

15 rotors

15A·15B Large diameter part

16a～16d blade

18 Lag angle oil passage

19 Advance angle oil passage

20 oil pump

20a Exhaust passage

21 The first solenoid switching valve

22 Exhaust passage

24 First locking hole

24a·24b First and second bottom surfaces

25 Second locking hole

26 First locking pin receiving hole

26b rear end

26c First opening (opening)

27 Second locking pin receiving hole

27b rear end

27c Second opening (opening)

28 First locking pin

28a Front end

29 Second locking pin

29a Front end

32 Second hydraulic circuit

36 Second solenoid switching valve

37 Path Components

Claims (12)

1. A valve timing control device for an internal combustion engine, comprising:

a housing that transmits a rotational force from a crankshaft and has a plurality of operation chambers therein;

a vane rotor fixed to the camshaft and having a plurality of vanes that partition the plurality of operation chambers, respectively;

a locking pin receiving hole provided to the vane rotor;

a locking pin slidably disposed inside the locking pin receiving hole;

a locking recess provided in the housing and into which an axial end portion of the locking pin is inserted;

the housing has an opening portion that opens to the outside at a position axially opposite to the locking recess portion,

the lock pin receiving hole has an opening portion for releasing back pressure at an end portion on the other end portion side in the axial direction of the lock pin,

the opening portion overlaps with the opening portion at a radially innermost portion with respect to a rotation axis of the vane rotor.

2. The valve timing control apparatus of an internal combustion engine according to claim 1,

the locking pin receiving hole has the opening portion and a sliding portion having the same inner diameter as the opening portion and allowing the locking pin to slide,

the opening portion is formed by an annular groove portion having an inner diameter larger than that of the sliding portion,

a part of the annular groove portion overlaps with the opening portion in a rotation axis direction of the vane rotor.

3. The valve timing control apparatus of an internal combustion engine according to claim 2,

the annular groove portion is formed in a conical shape, and a radius of one end of the opening portion side is formed larger than a radius of the other end of the sliding portion side in a rotation axis direction of the vane rotor.

4. The valve timing control apparatus of an internal combustion engine according to claim 3,

the vane rotor is formed by sintering molding,

the inner peripheral surface of the annular groove portion is formed as an unprocessed conical surface.

5. The valve timing control apparatus of an internal combustion engine according to claim 1,

the housing is cylindrical and has a housing main body having at least one axial opening and a plate member for closing the one axial opening of the housing main body,

the open portion is provided on an inner peripheral edge of a through hole formed through an inner peripheral portion of the plate member.

6. The valve timing control apparatus of an internal combustion engine according to claim 5,

the open portion is a recess recessed radially outward from an inner peripheral edge of the through hole of the plate member.

7. The valve timing control apparatus of an internal combustion engine according to claim 1,

the vane rotor includes a rotor fixed to the camshaft, a large diameter portion provided to extend radially outward from an outer periphery of the rotor, and the vane provided to extend radially outward from the large diameter portion,

the locking pin receiving hole is provided at the large diameter portion,

the large diameter portion overlaps with the opening portion in the axial direction over an entire range of a range in which the vane rotor rotates relative to the housing.

8. The valve timing control apparatus of an internal combustion engine according to claim 7,

the lock pin receiving hole is provided at a position on the large diameter portion that is offset radially inward from a center of a radial width centered on a rotation axis of the vane rotor.

9. The valve timing control apparatus of an internal combustion engine according to claim 8,

the locking recess is formed directly on an inner surface of the housing.

10. The valve timing control apparatus of an internal combustion engine according to claim 2,

the annular groove portion has a cross-sectional shape in a direction perpendicular to the axis formed in a different shape.

11. The valve timing control apparatus of an internal combustion engine according to claim 2,

the annular groove portion is formed in a stepped disk shape having a diameter larger than an inner diameter of the sliding portion of the lock pin receiving hole.

12. A valve timing control device for an internal combustion engine, comprising:

a housing that transmits a rotational force from a crankshaft and has a plurality of operation chambers therein;

a vane rotor fixed to the camshaft and having a plurality of vanes that partition the plurality of operation chambers, respectively;

a locking pin receiving hole provided to the vane rotor;

a locking pin slidably disposed inside the locking pin receiving hole;

a locking recess provided in the housing and into which an axial end portion of the locking pin is inserted;

an opening portion provided in the housing and penetrating the housing in a rotation axis direction of the housing to communicate an inside and an outside of the housing,

the lock pin receiving hole has an opening portion, a part of which is provided on the other end side in the axial direction of the lock pin, and the opening portion overlaps with the opening portion in the axial direction over the entire range of relative rotation of the housing and the vane rotor.

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