JP2001227306A - Valve opening and closing time control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that by using a knock pin to fix a phase of a camshaft (rotor) against a crankshaft is used on a valve opening and closing time control device of an internal combustion engine and fluid to control to put in and out this knock pin remains on a back surface of the knock pin, the knock pin is always pushed on the rotor installed on the camshaft, and a housing and the rotor are not relatively smoothly rotated. SOLUTION: Back pressure of the knock pin 224 is constantly removed by providing a drain line 2 buried in an outer plate 100 from a back surface position of the knock pin 224 in a siding hole 120. Additionally, it is devised so that the knock pin constantly retreats in the siding hole 120 at the time of phase adjustment by providing a third passage to transmit selected pressure to a knock pin stepped part by including a spark-advance pressure passage 302 connected to a spark-advance chamber 116, a delay-angle pressure passage 303 connected to a delay-angle chamber 118 and a change-over valve 301 to selectively change higher pressure of them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve opening / closing timing control device for variably controlling the valve opening / closing timing of an internal combustion engine, and more particularly to an improvement in an oil-sealed type.

[0002]

2. Description of the Related Art In order to improve the performance of an internal combustion engine, a valve opening / closing timing control device is used for controlling advance or delay of an intake valve and an exhaust valve within a predetermined range with respect to a rotational phase of a crankshaft. . This type of valve opening / closing timing control device includes a type that is housed and arranged inside the engine and allows some oil leakage, and a type that is arranged outside the engine and does not allow any oil leakage ( The latter requires various structural considerations in order to prevent oil leakage. The present invention relates to the above oil-sealed type. FIG.
FIG. 1 is an exploded perspective view showing an internal structure of a conventional valve timing control apparatus similar to that disclosed in Japanese Patent Application Publication No.
2 is a plan view showing the internal structure of FIG. 11, and FIG. 13 is a sectional view taken along the line DD of FIG. Note that FIG. 11 is a diagram for facilitating the understanding of the outline, and thus is a diagram in which details are omitted as compared with other drawings.

The timing pulley 70 is connected to a crankshaft of an engine (not shown) by a timing belt, and rotates synchronously. As shown in FIGS. 11 to 13, an internal rotor 96 is attached to the end of the camshaft 64 by a hollow bolt 94 so as not to rotate relatively. On the other hand, a bolt 98 is provided inside the timing pulley 70.
The outer plate 100, the housing 104, and the inner plate 102
Are mounted so that they cannot rotate relative to each other. The outer plate 100 secures a predetermined distance from the hollow bolt 94 by tightening the outer lid 106, and is sealed in a watertight manner.

[0004] Five vanes 108 are held in the inner rotor 96 in the radial direction of the camshaft 64, and a leaf spring 110 is provided at the inner peripheral end of the vane 108 as shown in FIG.
Are arranged, and bias the vane 108 to the outer peripheral side. On the inner peripheral side of the annular housing 104, five hydraulic chambers 114 partitioned from each other by the shoes 105 are provided.
A (fluid chamber) is formed between the outer peripheral wall of the internal rotor 96 and each hydraulic chamber 114 is partitioned by a vane 108 into an advance chamber 116 and a retard chamber 118. The timing pulley 70 rotates in the clockwise direction as indicated by the arrow in FIG. Also, the housing 104
Has an evacuation hole 120 extending in the radial direction.
A knock pin 124 that can engage with a receiving hole 122 formed in the outer peripheral wall of the internal rotor 96 is accommodated in the evacuation hole 120.

The internal rotor 96 is provided with the valve timing control device 8.
In FIG. 6, the receiving hole 122 is positioned so that the knock pin 124 is engaged with the receiving hole 122 at the most retarded position (the state shown in FIG. 12). The outer peripheral end of the evacuation hole 120 is closed by a lid 126 in a watertight manner. A spring 128 is disposed between the lid 126 and the knock pin 124, and urges the knock pin 124 toward the internal rotor 96. The valve opening / closing timing control device 86 controls the vane 108 based on a hydraulic pressure difference supplied to the advance chamber 116 and the retard chamber 118.
Is rotated within a range in which it moves inside the hydraulic chamber 114, thereby converting the phase between the timing pulley 70 and the camshaft 64.

As shown in FIG. 13, an external control oil pressure is supplied to an advance oil passage 401 and a retard oil passage 402,
A hydraulic passage (advancing oil passage 401) to the outside 16 extends from a groove formed on the outer periphery of the camshaft 64 in an outer hole 132 extending in the axial direction of the camshaft 64 and in a substantially radial direction of the internal rotor 96. And a first groove 134. Retard chamber 11
The hydraulic passage (retard oil passage 402) to the camshaft 6
4 to the hollow part of the hollow bolt 94, the head space 1
42, the second groove 14 extending substantially in the radial direction of the internal rotor 96
And 4.

[0007] The outer hole 132 and the receiving hole 12 which are the advance oil passages
A third hole 146 communicating between them is formed between the second hole 146 and the second hole 146. The third hole 146 has a first portion 147 formed in the inner rotor 96 and a second portion 147 formed in the inner plate 102.
148. Second part 148
Communicates with the first portion 147 only when the phase between the housing 104 and the internal rotor 96 reaches a phase at which the knock pin 124 can engage with the receiving hole 122. The third hole 1
46 ejects the knock pin 124 to the evacuation hole 120,
It can communicate with the advance chamber 116 via the communication passage 150. The communication passage 150 is formed on the inner peripheral side wall of the housing 104 and communicates between the evacuation hole 120 and the adjacent advance chamber 116.

[0008] A place on the outer peripheral side of the knock pin 124 where the spring 128 is disposed is called a rear chamber 152. A fourth groove 154 communicating between the rear chamber 152 and the head space 142 of the hollow bolt 94 is provided.
The fourth groove 154 includes a first portion 155 formed on the axial end surface of the internal rotor 96 and a second portion 156 formed on the axial end surface of the housing 104.
Part 155 and the second part 156
4 and the internal rotor 96 communicate only when the knock pin 124 can be engaged with the receiving hole 122.

When the camshaft 64 is advanced from the most retarded position shown in FIG. 12, that is, when the rotation of the camshaft 64 is advanced rather than the rotation of the timing pulley 70, a hydraulic control valve (not shown) is operated to advance the angle. Advance chamber 1 via oil passage
The oil is supplied to the retard chamber 16 and the oil in the retard chamber 118 is discharged through the retard oil passage. At this time, first, the oil is also supplied to the third groove 146 communicating with the advance oil passage, and the oil in the rear chamber 152 is also supplied to the fourth groove 154 communicating with the retard oil passage.
Is discharged through the receiving hole 1.
It is discharged from 22 and stored in the evacuation hole 120. Therefore, the internal rotor 96 can move freely, and the phase conversion between the housing 104 and the internal rotor 96 becomes possible.

However, it is often the case that minute bubbles are mixed in the hydraulic passage described above for some reason, and the hydraulic oil apparently exhibits compressibility. In such a state, the internal rotor 96 rotates to
At the moment when the first portion 155 and the second portion 156 of the groove 154 are displaced from each other and the flow is cut off, the back pressure of the knock pin 124 (the pressure in the back chamber 152) may not be completely removed. There is. That is, even though only the air bubbles are compressed and the oil is not discharged, the knock pin 124 is temporarily moved to the evacuation hole 12 as if the oil was discharged.
It is stored in 0.

Then, the lock is released and the housing 10 is released.
4, the internal rotor 96 rotates, and the knock pin 124
The flow passage to is closed. However, since the pressure in the rear chamber 152 remains as the compression pressure of the air bubbles, the knock pin 12
4, both the force of the spring 128 and the compression pressure are applied, and are strongly pressed to the inner peripheral side. This force continues to be applied until the operating state of the engine returns to the most retarded position again since there is no escape route for the pressure.
The inner rotor 96 and the inner rotor 96 are rubbed and one of them is damaged, and the rotation of the inner rotor 96 is hindered, so that smooth control of the valve opening / closing timing becomes impossible.

Even if the back pressure of the knock pin 124 remains slightly, the knock pin is
28, the knock pin 124 and the internal rotor 96 always rub against each other when the internal rotor 96 rotates with respect to the housing 104, thereby shortening the service life.

In the above description, the knock pin 124 is arranged in the radial direction of the camshaft 96 and the retracting hole 120 is provided on the housing 104 side. 9
It is known that the knock pin 124 is arranged in parallel with the inner rotor 6 or housed on the side of the inner rotor 96, and in this case, the same problem occurs only by changing the partner to which the knock pin 124 is pressed.

[0014]

The conventional oil-sealed valve opening / closing timing control device is configured as described above. 1) When the internal rotor rotates with respect to the housing, the knock pin is formed by a spring. There is a possibility that you are always pressed against the other party. 2) The oil passage may be closed without the back pressure of the knock pin being completely released, and the internal rotor may rotate while the knock pin is strongly pressed against the counterpart by both the spring and the oil pressure. As a result, the tip of the knock pin and the surface of the mating side that rubs against it are scratched, preventing smooth rotation of the internal rotor, making it impossible to control the valve opening and closing timing, and shortening the life of the device. there were.

3) Since the diameter of the receiving portion on the outer peripheral side of the spring is larger than the diameter of the spring, the position of the spring is likely to be shifted in a direction perpendicular to the axis of the spring. As a result, a force is applied obliquely to the knock pin. In addition, the structure is such that the hydraulic pressure for releasing the lock is applied to the tip of the knock pin.Therefore, the pressure must be applied from the bottom of the receiving hole.Therefore, the pressure is applied only when the knock pin is inserted into the receiving hole. There was a problem that it was not possible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and the back pressure of the knock pin does not remain, and the unlock hydraulic pressure can be applied to the knock pin regardless of the position of the internal rotor. When the internal rotor rotates with respect to the housing, the knock pin is sufficiently housed in the evacuation hole against the force of the spring, so that the knock pin does not rub against the mating side and the device life is long. It is an object to obtain a valve timing control device.

[0017]

A valve timing control apparatus according to the present invention is provided in an internal combustion engine having a camshaft for opening and closing an intake valve or an exhaust valve and a crankshaft for driving the camshaft. A valve opening / closing timing control device that transmits the rotation of the camshaft to a camshaft so that the rotation phase can be controlled. A rotor which is synchronously driven by a shaft, a rotor which is attached to the camshaft and has a plurality of vanes which divides the plurality of fluid chambers into an advance chamber and a retard chamber, respectively, and a first which supplies a fluid to the advance chamber Fluid passage and a second fluid supply to the retard chamber
Fluid passage, a retracting hole provided in one of the housing and the rotor so as to extend substantially in the radial direction of the rotor, a receiving hole provided in the other of the housing and the rotor, and sliding on the retracting hole. A phase holding mechanism including a knock pin arbitrarily disposed and partially engageable with the receiving hole when the housing and the rotor have a desired phase; and a fluid for releasing the engagement of the knock pin with the receiving hole. A third passage for applying pressure to the front surface of the knock pin in the evacuation hole, and a drain line for constantly discharging the fluid behind the knock pin in the evacuation hole to the inside of the internal combustion engine regardless of the relative position between the housing and the rotor. It is a thing.

The third passage is provided with a switching valve for selectively switching the higher of the fluid pressure in the advance chamber and the fluid pressure in the retard chamber to apply the pressure to the front surface of the knock pin. It is.

The housing has an outer plate or an inner plate for closing an axial end face of the fluid chamber, and the drain line is embedded in a plate constituting the outer plate or the inner plate.

Further, the outer plate or the inner plate includes an outer plate or an inner plate which closes an axial end face, and a plate provided in contact with the outer plate or the inner plate and having a drain line embedded therein.

The knock pin is slidably disposed in the evacuation hole and provided with a small-diameter portion engaged with the receiving hole, a large-diameter portion remaining in the evacuation hole, and provided between the small-diameter portion and the large-diameter portion. And a stepped portion for receiving the fluid pressure in the third passage.

The small diameter portion of the knock pin is smaller than the inner diameter of the receiving hole, and has a gap for discharging oil in the receiving hole between the knock pin and the wall surface of the receiving hole.

A stroke having a spring receiving hole for fixing a spring for urging the knock pin in the evacuation hole and restricting the movement of the knock pin, and a discharge path for discharging fluid in the spring receiving hole to a drain line. It is provided with a regulating member.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is an internal plan view showing the internal structure of a valve timing control apparatus (oil-sealed type) according to Embodiment 1 of the present invention, and FIG.
The cross section is shown in FIG. FIG. 3 is a partial configuration diagram illustrating a structure around the knock pin of FIG. In the following drawings, the same reference numerals as those in the conventional drawings denote the same or corresponding parts, and a detailed description thereof will be omitted. 1 to 3, a timing pulley 70 is connected to a crankshaft (not shown) of an engine by a timing belt, and rotates synchronously. A hollow bolt 94 is provided at the end of the camshaft 64.
Thereby, the internal rotor 96 (hereinafter referred to as the rotor) is attached so as not to rotate relatively. On the other hand, the timing pulley 7
The outer plate 100, the housing 104, and the inner plate 102 are attached to the inside of 0 by bolts 98 so as not to rotate relatively. The outer plate 100 secures a predetermined distance from the hollow bolt 94 by tightening the outer lid 106, and is sealed in a watertight manner.

The rotor 96 holds four vanes 108 in the radial direction of the rotor 96, and an oil seal is disposed at the tip of the vane 108. On the inner peripheral side of the annular housing 104, four hydraulic chambers 114 (fluid chambers) are formed between the outer peripheral wall of the rotor 96 and four hydraulic chambers 114 (fluid chambers) partitioned from each other by the shoes 105. The chamber is divided into an advance chamber 116 and a retard chamber 118. The housing 104 is provided with a retreat hole 120 extending in the radial direction.
Inside, a stepped knock pin (simply referred to as a knock pin) engageable with a receiving hole 122 formed in the outer peripheral wall of the rotor 96.
224 are accommodated.

The receiving hole 122 is positioned so that the knock pin 224 is engaged with the receiving hole 122 when the rotor 96 is at the most retarded position in the valve timing control device 86. The outer peripheral end of the evacuation hole 120 is closed by a lid 126 in a watertight manner. Between the lid 126 and the knock pin 224,
A spring 128 is arranged via a stroke regulating member 226, and urges the knock pin 224 toward the rotor 96. Reference numeral 1 denotes an oil drain hole provided on a side surface of the evacuation hole 120 of the housing 104 (specifically, a side surface of the rear chamber 152 on a back surface of the knock pin 224 in the evacuation hole 120), and 2 denotes an outer plate which rotates integrally with the housing 104. This is a drain line provided inside 100 and communicating the oil drain hole 1 with the head space 142 of the bolt 94.

FIG. 1 is a plan view showing the outer plate 100 of FIG. 2 in a see-through manner, and an oil passage leading to the retreat hole 120 is shown by a dotted line. FIG. 2 shows a cross section (BB) at the position of the evacuation hole 120 in FIG. The detailed structure around the evacuation hole 120 in FIGS. 1 and 2 is three-dimensionally shown in FIG. Stepped knock pin 22
The structure of No. 4 will be described in detail in Embodiment 3. The reference numeral 300 indicates that the stepped knock pin 224 is released from the locked position and
This is a lock release hydraulic hole for introducing a hydraulic pressure for movement into the inside 20. Reference numeral 301 denotes a switching valve provided in the middle of the unlock hydraulic pressure hole 300, which is an advanced pressure passage 302 communicating with the advance chamber 116 and a retard pressure passage 3 communicating with the retard chamber 118.
03 is the hydraulic release hole 30
The connection is automatically switched by automatically selecting 0.

The switching valve 301 shown in FIG.
02, and unlocking hydraulic hole 300 in the center
A circular valve 301A that can freely move is provided in an oval-shaped chamber having an opening, and the valve 30 is moved through the oval-shaped chamber by a higher pressure of the advance pressure passage 302 or the retard pressure passage 303.
Switching is performed by the movement of 1A. Although not shown in detail in the figure, the hydraulic path to the advance chamber 116 is referred to as a first fluid path, and the hydraulic path to the retard chamber 118 is referred to as a second fluid path. The first fluid passage includes a passage in the camshaft, a groove in a circumferential portion of the camshaft, and a groove formed by a contact surface between the housing 104 and the rotor 96, and applies a hydraulic pressure to the advance chamber 116. . The second fluid passage includes a passage in the camshaft, a groove in the camshaft, and a hole in the rotor, and applies a hydraulic pressure to the retard chamber 118. Evacuation hole 120,
The receiving hole 122 and the stepped dowel pin 224 constitute a phase holding mechanism. The lock release hydraulic hole 300, the switching valve 301, the advance pressure passage 302, and the retard pressure passage 303 constitute a third passage 403.

Next, the operation will be described with reference to FIGS. The point that the stepped knock pin 224 is always urged inward by the spring 128 is the same as the conventional one. However, from the rear chamber 152, the oil drain hole 1 and the drain line 2
Through the oil passage for releasing the hydraulic pressure (regardless of the angular position of the rotor 96) to the head space 142 of the hollow bolt 94 at all times, the rear chamber 15 of the stepped knock pin 224
2 and the stepped knock pin 224 is
It doesn't happen that you're being pushed hard. It is discharged from the head space 142 of the hollow bolt 94 into the engine via the camshaft 64.

Further, when the rotor 96 rotates with respect to the housing 104, the hydraulic pressure in either the advance chamber 116 or the retard chamber 118 becomes higher regardless of the magnitude of the movement angle. Is the stepped knock pin 22 from either the advance pressure passage 302 or the retard pressure passage 303 via the switching valve 301 and the unlock hydraulic pressure hole 300.
4, and the stepped knock pin 224 is pushed outward. That is, the stepped knock pin 224 is
Irrespective of whether it is in the state inserted in 22,
Whenever the rotor 96 rotates relative to the housing 104, it is urged to the outer periphery.

As a result, when the rotor 96 rotates, the stepped knock pin 224 does not rub against the rotor 96 and is not damaged, and the rotation of the rotor 96 is always smooth and the life of the apparatus is shortened. Disappears. The drain line 2 provided inside the outer plate 100 is provided in contact with the housing 104 on the side of the shoe 105, but is buried inside the outer plate 100 near the rotor 96.
Since it is stored, it does not leak to the rotor 96 side. While the vane 108 described in the drawing of the conventional one is plate-shaped, the one shown in FIGS. 1 to 3 is thicker,
This is shown as an example, and may be plate-shaped. In the above description, the drain line 2
Has been described as providing the switching valve 301 on the inner plate 102. However, the positions of the oil drain hole 1 and the unlock hydraulic pressure hole 300 are inverted, the drain line 2 is provided on the inner plate 102, and the outer plate 10
It goes without saying that the switching valve 301 may be provided at zero.

In the above description, the valve opening / closing timing control device attached to the intake valve camshaft which rotates in a specific direction has been described.
Since the number of vanes and the like can be freely changed depending on the design of the internal combustion engine, and the same applies to those used for the exhaust valve, the present invention is not limited to the embodiment described above. .

Embodiment 2 FIG. 1 to 3 of the first embodiment
In the above description, the drain line 2 is formed on the outer plate 100 (it may be formed on the inner plate 102).
02 is not a flat plate, and as described in Embodiment 1, there is a portion in which the drain line 2 must be buried and stored inside the thickness of the outer plate 100. Fig. 4
As shown in FIG. 5, the outer plate 3 having the drain line 2 embedded therein is inserted between the outer plate 100 and the housing 104, or the drain line 2 is formed between the inner plate 102 and the housing 104 as shown in FIG. May be inserted. In this case, whether the outer plate 3 or the inner plate 4, the housing 104
It is preferable to provide an appropriate detent such as a detent pin 5 shown in FIGS.

An oil passage which should be a drain line 2 provided on the outer plate 3 and the inner plate 4 is formed by forming a groove not penetrating the thickness of the outer plate 3 and the inner plate 4 on a surface in contact with the outer plate 100 or the inner plate 102. It is constructed by burying. According to such a method, it is possible to configure the configuration at a lower cost than that of the first embodiment.

Embodiment 3 FIG. Details of the structure around the stepped knock pin 224 of the valve timing control apparatus shown in FIG. 2 of the first embodiment (the cross-sectional position shown in FIG.
3 shows a position slightly different from the position BB. ) Is shown in FIG. In FIG. 6, reference numeral 224 denotes a stepped dowel pin, the details of which are shown in FIG. Stepped Dowel Pin 2
24 is a small-diameter portion 224B inserted into the receiving hole 122;
A large-diameter portion 224C having a larger diameter than the small-diameter portion 224B is provided in contact with the small-diameter portion 224B, and has a stepped portion (annular plane orthogonal to the axis) 224A therebetween.
The spring receiving hole 2 is provided inside the large diameter portion 224C.
24D is provided. Here, the stepped portion 224A does not necessarily have to be flat, and may be tapered. The stepped portion 224A in FIG. 7 is a pressure receiving surface according to the present invention.

In FIG. 6, reference numeral 226 denotes a stroke regulating member, which regulates a movement limit when the stepped knock pin 224 is retracted into the evacuation hole 120. The detailed structure is shown in FIG. 8, and its modification is shown in FIG. 8 and 9 includes a large-diameter portion 226C having the same diameter as the inner diameter of the evacuation hole 120, a contact surface 226A hitting the stepped knock pin 224, and a spring receiving hole 2 provided inside.
26D. Also, a hole or notch 22 for releasing the hydraulic pressure inside the spring receiving hole 226D to the outside is provided.
6B and a groove 226E for further releasing the released pressure to the oil drain hole 1. A groove for inserting an O-ring is provided on the outer periphery of the large diameter portion 226C.

Next, the operation will be described. The diameter of the spring receiving hole 226D of the stroke regulating member 226 is substantially the same as the diameter of the end of the spring 128 to be stored.
In 6D, there is almost no movement in the direction perpendicular to the axis of the spring, and therefore no force is exerted on the stepped knock pin 224 to tilt the knock pin.

The unlocking hydraulic pressure applied to the stepped knock pin 224 is applied not to the tip of the knock pin 224 but to the stepped portion 224A (that is, the portion accommodated in the pin housing). The unlock hydraulic pressure hole 300, which is an oil passage for applying pressure, can be provided on the housing 104 side irrespective of the position of the rotor 96. Also, a stepped knock pin 224
Is pressed against the stroke regulating member 226 in the evacuation hole 120, the spring receiving holes 224D and 226D
Is discharged through the notch 226B and the groove 226E.

The small-diameter portion 2 of the stepped knock pin 224
Since the diameter of 24B is considerably smaller than the diameter of the receiving hole 122 so that there is a gap therebetween, when the stepped knock pin 224 is put in and out of the receiving hole 122, the residual oil in the receiving hole 122 is reduced. The rotor 9 enters and exits through a gap between the stepped knock pin 224 and the wall of the receiving hole 122.
6 is discharged through the gap between the housing 6 and the housing 104, so that unnecessary hydraulic pressure is not applied to the stepped knock pin 224. In the modified example of the stroke regulating member 226 in FIG. 9, the notch 226B is
Can also serve as E. The groove on the outer periphery is a groove for inserting an O-ring.

Embodiment 4 FIG. FIG. 10 shows the knock pin 224.
In the fourth embodiment, the direction of operation is parallel to the axial direction of the camshaft 64. Since the position of the knock pin 224 is close to the center of the shaft, the force applied to the pin increases, so that consideration must be given to increasing the thickness, or the knock pin 224 is shortened to accommodate it within the axial length of the device. 22
Change of 4 shape, oil drain hole 1 leading to drain line 2
Although the details of the structure of the parts need to be changed, for example, the drain line 2 is buried in the outer plate 3, the basic configuration is the same as that of FIG. Therefore, detailed description is omitted.

In the drawings used in the description of the embodiments, the presence or absence of O-rings used in each part, the type of valve, the number of vanes and shoes, the positions of hydraulic passages, and the like are shown in the drawings. Needless to say, the present invention is not limited to the configuration having the above configuration.

[0042]

As described above, the valve timing control apparatus of the present invention is provided with the drain line for constantly discharging the fluid behind the knock pin, so that the knock pin is actuated by the fluid pressure while the rotor is rotating with respect to the housing. There is obtained an effect that the rotation is smooth and the life is prolonged without being strongly pressed against the rotor side.

Further, the third passage for supplying the fluid for releasing the lock by the knock pin selectively selects the higher one of the pressure of the fluid in the advance chamber and the pressure of the fluid in the retard chamber. Since the switching valve is provided to switch and pass, when the rotor rotates relative to the housing, the knock pin is always accommodated in the evacuation hole, and the knock pin is pressed against the other party, causing scratches and smooth rotation. The effect that no problem such as this occurs does not occur.

Since the drain line is embedded in the outer plate or the inner plate, the drain line can be provided at a low cost.

Further, since the outer plate or the inner plate includes a plate provided in contact with the outer plate or the inner plate and having a drain line embedded therein, the drain line can be constructed at a low cost.

Further, the knock pin has a small diameter portion, a large diameter portion, and a stepped portion, and receives fluid pressure through the third passage at the stepped portion. Can be provided at a portion which is not affected by the relative rotation.

Further, since the diameter of the small diameter portion of the knock pin is sufficiently smaller than the inner diameter of the receiving hole, it is possible to prevent the oil in the receiving hole from being easily discharged to the outside and becoming difficult to move due to the remaining hydraulic pressure.

Further, since the stroke regulating member provided in the evacuation hole is provided with a discharge path for constantly discharging the fluid in the spring receiving hole, the knock pin can be moved smoothly.

[Brief description of the drawings]

FIG. 1 is a diagram showing an internal structure of a valve opening / closing timing control device according to Embodiment 1 of the present invention by cutting out an outer plate.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a three-dimensional explanatory view of a structure around a knock pin of FIG. 1;

FIG. 4 is a sectional view of a valve timing control apparatus according to a second embodiment.

FIG. 5 is a cross-sectional view showing another configuration of the valve timing control apparatus according to the second embodiment.

FIG. 6 is a sectional view showing a structure around a knock pin of a valve timing control apparatus according to a third embodiment.

FIG. 7 is a view showing the shape of the knock pin of FIG. 6;

FIG. 8 is a view showing a shape of a stroke regulating member of FIG. 6;

FIG. 9 is a view showing a modification of the stroke regulating member of FIG. 6;

FIG. 10 is a diagram showing a configuration of a valve opening / closing timing control device according to a fourth embodiment.

FIG. 11 is an exploded perspective view showing the structure of a conventional valve timing control apparatus.

FIG. 12 is an explanatory diagram of an internal structure in which an outer plate of FIG. 11 is removed.

FIG. 13 is a sectional view taken along line CD of FIG.

FIG. 14 is a partially enlarged explanatory view of FIG. 12;

FIG. 15 is an explanatory diagram of a state where the internal rotor of FIG. 14 is rotated.

FIG. 16 is a partially enlarged explanatory view of FIG. 13;

[Explanation of symbols]

1 oil drain hole, 2 drain line, 64 cam shaft, 70 timing pulley, 94 hollow bolt, 96 internal rotor (rotor), 98 fixing bolt, 100 outer plate, 102 inner plate, 104 housing, 105 shoe, 106 outer cover, 108 vane, 116 advance chamber, 118 retard chamber, 120
Evacuation hole, 122 receiving hole, 124 knock pin, 128 spring, 152 rear chamber, 224
Stepped dowel pin, 300 Unlock hydraulic hole, 3
01 switching valve, 301A valve, 302 advance pressure passage, 303 retard pressure passage, 401 advance oil passage, 40
2 retard oil passage, 403 third passage.

Claims (7)

[Claims] 1. An internal combustion engine having a camshaft for opening and closing an intake valve or an exhaust valve and a crankshaft for driving the camshaft, and transmitting the rotation of the crankshaft to the camshaft so that the rotation phase can be controlled. A valve that is rotatably mounted on an outer periphery of the camshaft, has a plurality of fluid chambers partitioned by shoes inside, and a housing that is synchronously driven by the crankshaft; and the cam. A rotor attached to a shaft, the rotor having a plurality of vanes for dividing the plurality of fluid chambers into an advance chamber and a retard chamber, a first fluid passage for supplying fluid to the advance chamber, A second fluid passage for supplying fluid to the chamber; and extending in substantially one of the rotor and one of the housing and the rotor. And a receiving hole provided in the other of the housing and the rotor, and a slidably disposed hole in the retracting hole when the housing and the rotor have a desired phase. A phase holding mechanism including a knock pin whose portion is engageable with the receiving hole; and a third passage for applying a fluid pressure for releasing the engagement of the knock pin to the receiving hole to a front surface of the knock pin in the evacuation hole. And a drain line for constantly discharging the fluid on the back surface of the knock pin in the evacuation hole into the internal combustion engine regardless of the relative position between the housing and the rotor. Control device. 2. The switching device according to claim 1, wherein the third passage is provided with a switching valve for selectively switching the higher one of the pressure of the fluid in the advance chamber and the pressure of the fluid in the retard chamber to apply the pressure to the front surface of the knock pin. The valve opening / closing timing control device according to claim 1, wherein: 3. The housing according to claim 1, wherein the housing includes an outer plate or an inner plate for closing an axial end face of the fluid chamber, and the drain line is embedded in a plate constituting the outer plate or the inner plate. Or the valve timing control apparatus according to 2. 4. The outer plate or the inner plate includes an outer plate or an inner plate that closes an axial end face, and a plate provided in contact with the outer plate or the inner plate and having a drain line embedded therein. The valve opening / closing timing control device according to claim 1. 5. The knock pin is slidably disposed in the evacuation hole and is engaged with the receiving hole, a large-diameter portion remaining in the evacuation hole, and between the small-diameter portion and the large-diameter portion. 3. The valve timing control device according to claim 1, further comprising: a stepped portion provided in the first passage and receiving a fluid pressure in the third passage. 6. The valve according to claim 5, wherein the small-diameter portion of the knock pin is smaller than the inner diameter of the receiving hole, and has a gap for discharging oil in the receiving hole between the knock pin and the wall surface of the receiving hole. Timing control device. 7. A retraction hole, comprising a spring receiving hole for restricting the movement of the knock pin and fixing a spring for urging the knock pin, and a discharge passage for discharging fluid in the spring receiving hole to a drain line. The valve opening / closing timing control device according to claim 5, further comprising a stroke regulating member.