JPH1181926A - Valve timing adjusting device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve timing adjusting device capable of preventing foreign matter from being stored in a hydraulic chamber and surely operating a stopper piston. SOLUTION: Foreign matter in hydraulic fluid can be discharged from a hydraulic chamber to a hydraulic pump or a drain via a single hole 15 and an all around groove by hydraulic fluid operating in a spark advance hydraulic chamber 85 because the single hole 15 is communicated with the hydraulic chamber via an oil path 19 and the hydraulic chamber is communicated with the spark advance hydraulic chamber 85 via an oil path 40. Therefore, when hydraulic fluid is supplied to the hydraulic chamber, a stopper piston surely slipped off from a tapered bore and when hydraulic fluid is not supplied to the hydraulic chamber, the stopper piston surely fits into the tapered bore. Therefore, generation of striking sound of a vane rotor 4 and a shoe housing 7 can be surely prevented and the phase control of an intake valve by a hydraulic control can be surely performed. Therefore, stability of an engine can be improved and exhaust emission can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine (hereinafter referred to as "internal combustion engine").
The opening / closing timing of at least one of an intake valve and an exhaust valve of an “internal combustion engine” (hereinafter referred to as an engine)
The present invention relates to a valve timing adjusting device for changing “opening / closing timing” according to operating conditions.

[0002]

2. Description of the Related Art Conventionally, a camshaft is driven through a timing pulley or a chain sprocket that rotates synchronously with a crankshaft of an engine, and an intake valve and an exhaust valve are driven by a phase difference due to a relative rotation between the timing pulley or the chain sprocket and the camshaft. As a vane type valve timing adjusting device for controlling at least one of the valve timings, there is known a device disclosed in JP-A-9-60508.

In the valve timing adjusting device disclosed in Japanese Patent Application Laid-Open No. 9-60508, a hole is provided in a vane rotor which is a camshaft-side rotating body, and a stopper piston which can be fitted in this hole is formed by a crankshaft-side rotating body. A stopper piston is fitted in a hole when the camshaft is at the most retarded position or the most advanced position with respect to the chain sprocket, and restrains relative rotation between the two rotating bodies. With this, even when the camshaft is in the most retarded position or the most advanced position with respect to the chain sprocket, and the camshaft receives positive and negative torque fluctuations due to the driving of the intake valve or the exhaust valve, the shoe housing and the vane rotor are connected to each other. Can be prevented from occurring.

When the phase of the camshaft with respect to the chain sprocket is changed from the state in which the stopper piston is fitted in the hole, the stopper piston comes out of the hole by switching the oil passage, and the relative rotation between the chain sprocket and the camshaft is possible. become.

[0005]

However, in the valve timing adjusting device disclosed in Japanese Patent Application Laid-Open No. 9-60508, among the two hydraulic chambers into which hydraulic oil for introducing the stopper piston out of the hole is introduced. The hydraulic chamber into which hydraulic oil acting on the flange portion of the stopper piston is introduced is a dead end. For this reason, if foreign matter that cannot be filtered by the filter is mixed into the hydraulic oil, the foreign matter is pressed against the inner peripheral wall of the hydraulic chamber by centrifugal force generated by rotation of the valve timing adjusting device, so that there is no escape place. Then, as the operation of the valve timing adjusting device is repeatedly performed, foreign matter accumulates, and the stopper piston may be locked so that the stopper piston cannot come out of the hole or cannot be fitted in the hole.

When the stopper piston cannot be fitted into the hole, the camshaft receives positive and negative torque fluctuations due to the driving of the intake valve or the exhaust valve, and a tapping sound may be generated between the shoe housing and the vane rotor. Further, when the stopper piston cannot come out of the hole, the overlap period in which the intake valve and the exhaust valve are simultaneously opened is reduced, and the exhaust emission may be deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and provides a valve timing adjusting device capable of preventing foreign matters from accumulating in a hydraulic chamber and reliably operating a stopper piston. The purpose is to do.

[0008]

According to the valve timing adjusting device for an engine according to the present invention, the foreign matter accumulation preventing means includes a vane extending from one circumferential end to the other circumferential end of the storage chamber. Due to the fluid pressure when the member moves,
Foreign matter accumulates in the release pressure chamber where fluid pressure is applied to displace the contact portion in the direction of releasing the restraint of the restraining means that restrains the relative rotation between the housing member and the vane member at one circumferential end of the storage chamber. To prevent. For this reason, since the restraining means can be reliably operated, it is possible to reliably prevent the occurrence of a tapping sound between the housing member and the vane member, and to control the phase of the intake valve and the exhaust valve by controlling the pressure of the working fluid. It can be done reliably. Therefore, the stability of the engine can be improved, and the exhaust emission can be reduced.

According to the second aspect of the present invention, the foreign matter accumulation preventing means has a discharge passage through which the working fluid in the release pressure chamber can be discharged outside the release pressure chamber. Can be reliably operated. Therefore, it is possible to reliably prevent the occurrence of a tapping sound between the housing member and the vane member, and it is possible to reliably perform the phase control of the intake valve and the exhaust valve by controlling the pressure of the working fluid.

According to the valve timing adjusting device for an engine of the present invention, the fluid-driven driving means moves the vane member from one circumferential end toward the other circumferential end. A first fluid pressure to be rotated and a second fluid pressure to relatively rotate the vane member in a direction opposite to the first fluid pressure are supplied, and the contact portion is displaced to release the restrained state between the housing member and the vane member. I do. The contact portion receives a first fluid pressure to release a restrained state between the housing member and the vane member, and receives a second fluid pressure to release a restrained state between the housing member and the vane member. And a second pressure receiving surface. Therefore, the restraining means can be reliably operated without increasing the working fluid pressure by increasing the size of the fluid supply source and without increasing the pressure receiving area by increasing the size of the contact portion.

According to the valve timing adjusting device for an engine of the present invention, in the configuration in which the driving force of the drive shaft is received by the timing pulley, the working fluid and the air leaking from the housing chamber into the cover from the timing pulley. It has a passage for discharging to a remote location. Thus, when the working fluid is, for example, oil, it is possible to prevent the timing belt from getting wet and slipping on the leaked oil. Furthermore, when the working fluid is supplied, the residual air in the storage chamber is pressurized, and it is possible to prevent the restraint by the restraining means from being released at a time other than a desired time due to the air pressure.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an engine valve timing adjusting apparatus according to an embodiment of the present invention.
And FIG. The valve timing adjusting device 100 of the present embodiment is of a hydraulic control type and controls the valve timing of an intake valve.

The timing pulley 8 shown in FIG. 1 is coupled with a crankshaft as a drive shaft of an engine (not shown) by a timing belt (not shown) to transmit a driving force, and rotates in synchronization with the crankshaft. Rear member 5
Reference numeral 0 denotes a plate portion 51 and a bearing portion 52, and the plate portion 51, the timing pulley 8, and a shoe housing 7 described later are connected by bolts 53. The camshaft 1 as a driven shaft receives a driving force from the timing pulley 8 and drives an intake valve (not shown) to open and close. The camshaft 1 is supported by a cylinder head (not shown) via a journal portion 2 and is rotatable relative to the timing pulley 8 with a predetermined phase difference. The timing pulley 8 and the camshaft 1 rotate clockwise as viewed from the left in FIG. Hereinafter, this rotation direction is referred to as an advance direction.

In the shoe housing 7, a peripheral wall 71 and a front portion 72 are integrally formed, and together with the rear member 50, constitute a housing member. Both end surfaces in the axial direction of the vane rotor 4 are covered by the front portion 72 of the shoe housing 7 and the plate portion 51 of the rear member 50.
The timing pulley 8, the shoe housing 7, and the rear member 50 constitute a driving-side rotating body, and are coaxially connected to each other by bolts 53.

As shown in FIG. 2, the shoe housing 7 has trapezoidal shoes 7a formed at substantially equal intervals in the circumferential direction.
7b and 7c. Fan-shaped spaces 55 for accommodating vanes 4a, 4b, 4c as vane members are formed in three circumferential gaps between the shoes 7a, 7b, 7c, respectively, and the inner peripheral surfaces of the shoes 7a, 7b, 7c. Is formed in an arc-shaped cross section.

The vane rotor 4 has vanes 4a, 4b, 4c at substantially equal intervals in the circumferential direction.
4c is rotatably accommodated in a fan-shaped space 55 formed in a circumferential gap between the shoes 7a, 7b, 7c.
Arrows indicating the retard direction and the advance direction shown in FIG. 2 indicate the retard direction and the advance direction of the vane rotor 4 with respect to the shoe housing 7. In FIG. 2, each vane is located at one circumferential end of each fan-shaped space 55, and the vane rotor 4 is at the most retarded position with respect to the shoe housing 7. The most retarded position is defined by the retard side surface of the vane 4b being locked to the advance side surface of the shoe 7a. As shown in FIG. 1, the vane rotor 4 and the bush 6
And is integrally connected to the camshaft 1 to form a driven-side rotating body. The shoe housing 7 that supports the bush 6 is covered with a cover 58 on the side opposite to the timing pulley, and the cover 58 is fixed to the shoe housing 7 with screws 59 by screws. The holes 32 provided in the bolts 5 return the hydraulic oil leaked from the circumferential end of the vane rotor 4 to the cylinder head.

The camshaft 1 and the bush 6 are fitted to the bearing portion 52 of the rear member 50 and the inner peripheral wall 72a of the front portion 72 so as to be relatively rotatable. Therefore, the camshaft 1 and the vane rotor 4 can rotate relative to the timing pulley 8 and the shoe housing 7 coaxially. As shown in FIG. 2, the seal member 9 is fitted on the outer peripheral wall of the vane rotor 4. Vane rotor 4
A small clearance is provided between the outer peripheral wall of the shoe and the inner peripheral wall of the shoe housing 7, and the seal member 9 prevents the hydraulic oil from leaking between the hydraulic chambers through the clearance. Each of the seal members 9 is pressed toward the inner peripheral wall of the peripheral wall 71 by the urging force of the leaf spring 10.

As shown in FIG. 1, the guide ring 91 is press-fitted and held on the inner wall of the vane 4a.
, A stopper piston 17 is inserted as a contact portion. The stopper piston 17 is formed in a bottomed cylindrical shape having substantially the same outer diameter, and is accommodated in the guide ring 91 so as to be slidable in the axial direction of the camshaft 1. The stopper piston 17 is urged toward the front portion 72 by a spring 16 as urging means. The fitting ring 54 is fitted in a fitting hole formed in the front part 72, and a tapered hole 54 a as a contacted part is formed in an inner peripheral wall of the fitting ring 54. The stopper piston 17 can be fitted into the tapered hole 54a at the most retarded position shown in FIG. When the stopper piston 17 is fitted in the tapered hole 54a and the stopper piston 17 is in contact with the tapered hole 54a in the rotational direction, the relative rotation of the vane rotor 4 with respect to the shoe housing 7 is restricted. That is, the stopper piston 17 and the tapered hole 54a are in the restrained position at the most retarded position.
The stopper piston 17, the tapered hole 54a and the spring 16 constitute a restraining means.

The hydraulic chamber 18 on the left side of the flange portion 17b is
The oil passage 19 shown in FIG. 2 communicates with an advanced hydraulic chamber 85 described later. The hydraulic chamber 27 formed on the distal end side of the cylindrical portion 17a communicates with a retard hydraulic chamber 80 described later via an oil passage 31 shown in FIG. The first pressure receiving surface of the cylindrical portion 17a receiving the hydraulic pressure in the hydraulic chamber 27 and the second pressure receiving surface of the flange portion 17b receiving the hydraulic pressure in the hydraulic chamber 18 receive from the hydraulic oil in the hydraulic chamber 27 and the hydraulic chamber 18, respectively. The force acts in a direction to pull the stopper piston 17 out of the tapered hole 54a. The pressure receiving area of the first pressure receiving surface is substantially equal to the cross-sectional area of the cylindrical portion 17a, and the pressure receiving area of the second pressure receiving surface is approximately equal to the area of the annular portion corresponding to the diameter difference between the flange portion 17b and the cylindrical portion 17a. When hydraulic oil of a predetermined pressure or more is supplied to the retard hydraulic chamber 80 or the advance hydraulic chamber 85, the stopper piston 17 comes out of the tapered hole 54a against the urging force of the spring 16 due to the hydraulic pressure of the hydraulic oil.

Position of stopper piston 17 and tapered hole 5
The position of 4a means that when the vane rotor 4 is at the most retarded position with respect to the shoe housing 7, that is, when the camshaft 1 is at the most retarded position with respect to the crankshaft, the stopper piston 17 Are set at positions where they can be fitted into the tapered holes 54a. In the present embodiment, the most retarded position indicates one circumferential end of the fan-shaped space 55 that is the accommodation room, and the most advanced position is the other circumferential end of the fan-shaped space 55 that is the accommodation room. Is represented.

A communication passage 29 communicating with the back pressure chamber 30 of the stopper piston 17 is formed on the rear member 50 side of the vane 4a. The communication passage 29 has a bearing 52 at the most retarded position.
Communicates with the communication passage 28 formed at the bottom. Since the communication passage 28 is open to the atmosphere in the oil lubrication space of the engine (not shown),
At the most retarded position, the back pressure chamber 30 is open to the atmosphere.
Therefore, at the most retarded position, the stopper piston 17
Movement is not hindered. When the vane rotor 4 is rotated from the most retarded position to the advanced side, that is, when the vane rotor 4 is rotated to a non-constrained position where the stopper piston 17 and the tapered hole 54a cannot be fitted, the communication between the communication passage 29 and the communication passage 28 is stopped. Will be shut off.

As shown in FIG. 2, the shoe 7a and the vane 4
a, a retard hydraulic chamber 80 is formed between the shoe 7b and the vane 4b, and a retard hydraulic chamber 81 is formed between the shoe 7b and the vane 4b.
A retard hydraulic chamber 82 is formed between the hydraulic pressure c and the vane 4c. An advanced hydraulic chamber 83 is formed between the shoe 7a and the vane 4b, an advanced hydraulic chamber 84 is formed between the shoe 7b and the vane 4c, and an advanced hydraulic chamber is formed between the shoe 7c and the vane 4a. A chamber 85 is formed.

As shown in FIG. 1, the boss portion 4d of the vane rotor 4 is provided with an oil passage 13 formed in an arc shape at a contact portion with the bush 6. The oil passage 13 communicates with a hydraulic pump or a drain (not shown) as driving means via the oil passage 12 and the entire circumferential groove 11. Also, as shown in FIG. 2, a single hole 15 is formed in the boss 4d. The single hole 15 communicates with a hydraulic pump or a drain (not shown) as driving means (not shown) through an entire circumferential groove 11 via an oil passage (not shown). The hydraulic pump also serves as a drive source for engine lubrication oil.

The oil passage 13 communicates with the advance hydraulic chambers 83 and 84 via oil passages 56 and 57 as shown in FIG. The single hole 15 communicates with a hydraulic chamber 18 via an oil passage 19 as a discharge passage, and the hydraulic chamber 18 communicates with an advance hydraulic chamber 85 via an oil passage 40. The oil passage 19 is a discharge passage for preventing foreign matter from accumulating in the hydraulic chamber 18, and discharges foreign matter in the hydraulic oil to the outside of the hydraulic chamber 18 by operating hydraulic pressure that operates on the advance hydraulic chamber 85. It is for. The single hole 15 and the oil passage 19 constitute foreign matter accumulation preventing means. The hydraulic pressure of the hydraulic oil supplied to the advance hydraulic chambers 83, 84, 85 is the second fluid pressure.

As shown in FIG. 3, the vane rotor 4 has
An arc-shaped oil passage 22 and a single hole 23 are provided at a contact portion with the camshaft 1, and the oil passage 22 and the single hole 23 are provided.
Is connected to the hydraulic pump or drain via the entire circumferential groove 20 of the journal portion 2. Further, the oil passage 22
The oil passages 60, 61, and 62 respectively cause the retard hydraulic chamber 80,
It communicates with 81 and 82 and communicates with the hydraulic chamber 27 via the oil passage 31 shown in FIG. Retard hydraulic chambers 80, 81,
The hydraulic pressure of the hydraulic oil supplied to 82 is the first fluid pressure.

Next, the operation of the valve timing adjusting device 1 will be described. At the time of starting the engine, when the hydraulic oil has not yet been introduced into the hydraulic chambers 18 and 27 from the hydraulic pump, the vane rotor 4 is at the most retarded position shown in FIG. The distal end of the cylindrical portion 17a of the stopper piston 17 is fitted into the tapered hole 54a by the urging force of the spring 16, and the fitting causes the vane rotor 4 and the shoe housing 7 to be firmly restrained. Therefore, even when the camshaft 1 receives positive / negative torque fluctuations when driving the intake valve,
The vane rotor 4 is restricted from moving toward the retard side and the advance side with respect to the shoe housing 7, so that no relative rotational vibration is generated. Is prevented from occurring.

After starting the engine, first, hydraulic oil is supplied to each of the retard hydraulic chambers. When the hydraulic oil is supplied from the hydraulic pump, the hydraulic oil is introduced from the oil passage 22 into the retard hydraulic chambers 80, 81, 82 via the oil passages 60, 61, 62, respectively.
Further, the hydraulic chamber 27 is moved from the retard hydraulic chamber 80 through the oil passage 31.
Hydraulic oil is introduced into When the hydraulic pressure of the hydraulic oil supplied to the retard hydraulic chamber 80 becomes equal to or higher than a predetermined pressure, the force received by the first pressure receiving surface of the stopper piston 17 from the hydraulic chamber 27
Stopper piston 17 against the urging force of spring 16
Escapes from the tapered hole 54a, and the restraint of the vane rotor 4 from the shoe housing 7 is released.

Even if the stopper piston 17 comes out of the tapered hole 54a, the vane rotor 4 is kept in the retarded hydraulic chambers 80, 8
1 and 82, the hydraulic pressure is received in the retard direction, and the average of the positive and negative torque fluctuations received by the camshaft 1 urges the vane rotor 4 to the retard side with respect to the shoe housing 7, so that the vane rotor 4 7 is still held at the most retarded position shown in FIG. 2, that is, at one circumferential end of the storage chamber 55. For this reason, generation of a tapping sound between the vane rotor 4 and the shoe housing 7 is suppressed.

Next, the hydraulic pressure is switched from the state shown in FIG. 2 to open the retard hydraulic chambers 80, 81, 82 to the atmosphere and supply hydraulic oil to the advance hydraulic chambers 83, 84, 85. The vane rotor 4 moves in the rightward direction in FIG. By adjusting the hydraulic pressure in each hydraulic chamber in this manner, the relative phase difference of the vane rotor 4 with respect to the shoe housing 7, that is, the relative phase difference of the camshaft 1 with respect to the crankshaft can be controlled.

When the vane rotor 4 rotates from the most retarded position to the advanced position with respect to the shoe housing 7, the circumferential position between the stopper piston 17 and the tapered hole 54a shifts, so that the stopper piston 17 is fitted into the tapered hole 54a. No longer. When the engine stops, the retard hydraulic chambers 80, 8
1 and 82, the hydraulic oil is no longer supplied to the advance hydraulic chambers 83, 84 and 85, so that the vane rotor 4 moves the shoe housing 7 to the most retarded position shown in FIG. Stop at Hydraulic chamber 18, 2
7 is not supplied with hydraulic oil, the stopper piston 1
7 is fitted into the tapered hole 54a by the urging force of the spring 16.

In the present embodiment, the single hole 15 communicates with the hydraulic chamber 18 via the oil passage 19, and the hydraulic chamber 18 communicates with the advance hydraulic chamber 85 via the oil passage 40. Room 85
The foreign material in the operating oil is removed from the hydraulic chamber 1 by the operating oil pressure
8 to a hydraulic pump or drain via a single hole and a circumferential groove 11. For this reason, when hydraulic oil is supplied to the hydraulic chambers 18 and 27, the stopper piston 17 surely comes out of the tapered hole 54a, and the hydraulic chamber 1
When the hydraulic oil is not supplied to 8, 27, the stopper piston 17 is securely fitted into the tapered hole 54a. Therefore,
It is possible to reliably prevent the striking sound between the vane rotor 4 and the shoe housing 7, and to surely control the phase of the intake valve by hydraulic control. Therefore, the stability of the engine can be improved, and the exhaust emission can be reduced.

Since the hydraulic oil is supplied to the hydraulic chamber 18 whose second pressure receiving surface receives the hydraulic pressure via the advance hydraulic chamber 85, the hydraulic oil is supplied through a dedicated oil passage without passing through the advance hydraulic chamber 85. , The pressure in the hydraulic chamber 1 is higher than the pressure in the advance hydraulic chamber 85.
8 does not rise quickly. Therefore, when the valve timing is switched from the most retarded position to the advanced side, only the stopper piston 17 comes out of the tapered hole 54a before the hydraulic pressure of the advanced hydraulic chamber reaches the predetermined pressure required for rotating the vane rotor 4. Further, it is possible to prevent the vane rotor 4 from colliding with the shoe housing 7 due to the fluctuation of the cam torque and generating a tapping sound.

The air and hydraulic oil leaked into the cover 58 are discharged outside the apparatus at a position separated from the timing pulley 8 through the holes 32 provided in the bolts 5.
It is possible to prevent the timing belt from slipping wet with the hydraulic oil. In this embodiment, the valve timing adjusting device for driving the intake valve has been described. However, the present invention may be applied to a valve timing adjusting device for driving the exhaust valve, or a valve for driving both the intake valve and the exhaust valve. The present invention may be applied to a timing adjustment device.

In the present embodiment, the vane rotor 4 having three vanes has been described. However, in the present invention, the number of vanes may be one or more as long as the configuration allows. In the present embodiment, the stopper piston 1
7 moves in the axial direction of the vane rotor 4 and fits into the tapered hole. However, in the present invention, the stopper piston may move in the radial direction of the vane rotor and fit in the tapered hole. It is also possible to house the stopper piston in the housing.

Further, in this embodiment, a configuration in which the rotational driving force of the crankshaft is transmitted to the camshaft by the timing pulley is employed, but a configuration in which a chain sprocket, a timing gear, or the like is used may be employed. It is also possible to receive the driving force of the crankshaft as the drive shaft by the vane rotor and rotate the camshaft as the driven shaft and the shoe housing integrally.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a valve timing adjusting device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1, illustrating the valve timing adjusting device according to the embodiment of the present invention;

FIG. 3 is a sectional view taken along the line III-III of FIG. 1 showing the valve timing adjusting device according to one embodiment of the present invention;

[Explanation of symbols]

 Reference Signs List 1 camshaft (driven shaft) 4 vane rotor 4a, 4b, 4c vane (vane member) 7 shoe housing (housing member) 8 timing pulley 16 spring (biasing means) 18 hydraulic chamber 15 single hole 17 stopper piston (contact portion) Reference Signs List 19 oil passage (discharge passage) 27 hydraulic chamber 50 rear member (housing member) 54a tapered hole (contacted part) 55 fan-shaped space (accommodation chamber) 80, 81, 82 retarded hydraulic chamber 83, 84, 85 advance Hydraulic chamber 100 Valve timing adjustment device

Claims (4)

[Claims] 1. A driving force transmission system for transmitting driving force from a driving shaft of an internal combustion engine to a driven shaft that opens and closes at least one of an intake valve and an exhaust valve of the internal combustion engine, wherein the driving shaft or the driven shaft is provided. A housing member that rotates with one of the drive shaft and the other of the driven shaft and the other of the drive shaft and the driven shaft, and is rotatable relative to the housing member within a predetermined angle range in a housing chamber formed in the housing member. A vane member to be accommodated, an abutting portion and an abutted portion respectively provided on the housing member and the vane member, wherein the vane member is located at one circumferential end of the accommodation chamber. An abutting portion and an abutted portion that restrain relative rotation of the vane member with respect to the housing member by abutting on each other, and abutting on the abutted portion; Restraining means having biasing means for biasing the contact portion in a direction, wherein the contact portion is configured to be displaceable in a restraint releasing direction against a biasing force of the biasing means; By the fluid pressure when the vane member moves from the direction end to the other circumferential end of the accommodation chamber,
A valve timing adjusting device for an internal combustion engine, comprising: foreign matter accumulation preventing means for preventing foreign matter from accumulating in a release pressure chamber to which a fluid pressure for displacing the contact portion in a constraint releasing direction is applied. 2. The valve timing adjustment for an internal combustion engine according to claim 1, wherein said foreign matter accumulation preventing means has a discharge passage through which a working fluid in said release pressure chamber can be discharged outside said release pressure chamber. apparatus. 3. A first fluid pressure for relatively rotating the vane member from the one circumferential end to the other circumferential end, and the vane member in a direction opposite to the first fluid pressure. And a second fluid pressure for relatively rotating the housing member and the vane member by displacing the contact portion against the urging means by the first fluid pressure and the second fluid pressure. A first pressure-receiving surface that releases the restrained state of the housing member and the vane member by receiving the first fluid pressure; and The valve timing adjusting device for an internal combustion engine according to claim 1 or 2, further comprising a second pressure receiving surface configured to release a restrained state between the housing member and the vane member by receiving the second fluid pressure. 4. A valve timing adjusting device for an internal combustion engine which receives a driving force of said drive shaft by a timing pulley, wherein said cover includes a driven shaft and covers a bearing portion of a driven-side rotating body that rotates together with said driven shaft. The housing member is attached to a side wall on a side opposite to the timing pulley, and has a passage for discharging working fluid and air in the housing chamber leaking into the cover via the bearing portion to a position separated from the timing pulley. 4. The valve timing adjusting device for an internal combustion engine according to claim 1, 2 or 3.