JP2000002104A - Valve timing adjusting device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of strike noise of a housing member and a vane member by driving and holding the vane member on the housing member toward a non-constraining state by both of first fluid pressure changing valve timing to an advance angle side and second fluid pressure changing valve timing to a lag angle side. SOLUTION: At the time of starting an engine, a vane rotor 9 as a vane member is located at a most lag angle location for a shoe housing 3 as a housing member and transmits rotational driving force to a cam shaft 2 from a chain sprocket 1 via the shoe housing 3 and the vane rotor 9. A tip part 7c of a stopper piston 7 is fitted into a stopper hole 20 by energizing force of a spring 18, the vane rotor 9 and the shoe housing 3 are energized in a rotating direction and are strongly constrained, and the vane rotor 9 is regulated in movement to a lag angle side and an advance angle side for the shoe housing 3. As a result, rotational vibration is not generated and generation of strike noise can be prevented.

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 present invention relates to a valve timing adjusting device for changing the opening / closing timing of at least one of an intake valve and an exhaust valve of an “internal combustion engine” 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 opening and closing at least one of the valves, one disclosed in Japanese Patent Application Laid-Open No. 1-92504 is known.

In the device disclosed in Japanese Patent Application Laid-Open No. 1-92504, knock pins are accommodated on both sides in the radial direction of a timing pulley. The rotating rotor rotates with the camshaft and the vane, and is rotatable relative to the timing pulley. The rotary rotor is provided with a hole into which one of the two knock pins can be fitted when the vane rotates in the retard direction or the advance direction with respect to the timing pulley.

For this reason, when the rotary rotor rotates in the retard direction or the advance direction with respect to the timing pulley together with the vane, the timing pulley and the rotary rotor rotate together because the knock pin is fitted into the hole of the rotary rotor. .
Further, when changing the phase of the rotary rotor with respect to the timing pulley from the state where the knock pin is fitted in the hole,
By switching the hydraulic pressure, the knock pin comes out of one hole, and the rotary rotor rotates and then the knock pin fits in the other hole, so that the timing pulley and the rotary rotor rotate again together.

Thus, even if the camshaft generates a positive or negative torque with respect to the timing pulley due to the driving of the intake valve or the exhaust valve, the timing pulley and the rotary rotor are connected by the knock pin. And the timing pulley can be prevented from hitting.

[0006]

However, in the method disclosed in Japanese Patent Application Laid-Open No. 1-92504, the knock pin rotates each time the rotary rotor rotates in the advance or retard direction with respect to the timing pulley. As it comes out of one hole of the rotor and fits into the other hole, the knock pin and the hole are liable to wear, and if the knock pin and the hole are not machined with high precision, the knock pin cannot fit into the hole or the tapping sound is generated at the time of fitting. May occur.

Further, since the knock pin operates in the radial direction of the rotating rotor, there is a problem that centrifugal force may affect the operation of the knock pin.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and restrains the housing member and the vane member when the fluid at a predetermined pressure is not supplied from the driving means. An object of the present invention is to provide an engine valve timing adjustment device that prevents occurrence of a tapping sound.

[0009]

According to the valve timing adjusting device for an engine according to the first aspect of the present invention, the abutting portion sets the first fluid pressure for changing the valve timing to the advanced side and the valve timing for the valve timing to the advanced side. , And is driven and held toward the unconstrained state by both the second fluid pressure and the second fluid pressure.

Therefore, when the fluid pressure is supplied from the driving means to any one of them, the contact portion can be always kept in the non-constrained state, so that the number of operations of the contact portion can be reduced, and the durability can be reduced. Can be improved.

In the valve timing adjusting device for an engine according to the second aspect of the present invention, the contact portion receives the fluid pressure supplied from the driving means to release the restraint between the housing member and the vane member. The first pressure receiving surface is acted upon by the first fluid pressure supplied from the drive means so as to rotate the vane member relative to the housing member in the advance direction with respect to the first pressure receiving surface. The second fluid pressure supplied from the driving means acts so as to rotate the vane member relative to the housing member in the retard direction. As described above, the first and second pressure receiving surfaces respectively have the first and second pressure receiving surfaces.
The second fluid pressure may be received.

According to the third aspect of the present invention, the fluid bumper for reducing the displacement speed of the contact portion is formed between the contact portion and the contacted portion. The fluid acting on the contact portion in a transition period in which the contact portion is displaceable in the direction in which the housing member and the vane member are constrained, and the fluid pressure is switched from the constraint release state to another constraint release state. When the pressure drops momentarily, the contact portion can be prevented from being momentarily displaced in the restraining direction.

According to the valve timing adjusting device for an engine according to the fourth aspect of the present invention, when the restraint is released,
When the contact portion closes the communication hole with the outside of the back pressure chamber, the atmosphere cannot be introduced into the back pressure chamber from the communication hole even if the contact portion is displaced in the restraining direction. Is reduced.

Thus, the contact portion is located at a position where the contact portion can be displaced in the direction in which the housing member and the vane member are constrained, and the contact portion is in a transition period when the fluid pressure switches from the unconstrained state to another unconstrained state. When the fluid pressure acting on the portion drops momentarily, the contact portion can be prevented from being momentarily displaced in the restraining direction.

According to the fifth aspect of the present invention, the contact portion and the contacted portion contact each other when the driven shaft is in the most retarded state where the driven shaft is most retarded, The housing member and the vane member are mutually restrained.

Thus, the housing member and the vane member are constrained at the most retarded position where the engine has excellent startability, so that the fluid pressure supplied by the driving means is not sufficiently increased, such as when starting the engine. Further, it is possible to prevent the tapping sound of the valve timing adjusting device from occurring while ensuring the startability of the engine.

When the vane member rotates with the driven shaft, the housing member and the vane member are restrained when the vane member is at the most retarded position with respect to the housing member. Can be achieved. On the other hand, when the vane member rotates together with the drive shaft, this is achieved by restraining the housing member and the vane member when the vane member is at the most advanced position with respect to the housing member.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a plurality of embodiments showing the embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIGS. 1 to 8 show an engine valve timing adjusting apparatus according to a first embodiment of the present invention. FIG.
1 shows a hydraulic circuit according to the first embodiment.

A chain sprocket 1 shown in FIG. 1 receives a driving force transmitted from a crankshaft (not shown) as a drive shaft of an engine by a chain (not shown), and rotates in synchronization with the crankshaft.

The camshaft 2 as a driven shaft receives a driving force from the chain sprocket 1 and opens and closes at least one of an intake valve and an exhaust valve (not shown). The camshaft 2 is rotatable with a predetermined phase difference with respect to the chain sprocket 1. Chain sprocket 1
The camshaft 2 rotates clockwise as viewed from the arrow X direction shown in FIG. Hereinafter, this rotation direction is referred to as an advance direction.

As shown in FIGS. 1 and 2, the chain sprocket 1, the shoe housing 3, and the front plate 4, which are housing members, are coaxially fixed by bolts 14. Boss part 1a of chain sprocket 1
Of the camshaft 2 is rotatably fitted with the inner peripheral wall of the camshaft 2. The front plate 4 and the shoe housing 3 are positioned in the rotational angle direction by the knock pins 26, and the shoe housing 3 and the chain sprocket 1 are positioned in the rotation angle direction by the knock pins 27.

As shown in FIG. 2, the shoe housing 3 has trapezoidal shoes 3a and 3b facing each other. Opposite surfaces of the shoes 3a and 3b are formed in an arc-shaped cross section, and vanes 9a and 9b are respectively provided in two circumferential gaps between the shoes 3a and 3b.
A fan-shaped space, which is an accommodation room, is formed.

As shown in FIGS. 1 and 2, the vane rotor 9 as a vane member has fan-shaped vanes 9a and 9b at both ends in the radial direction, and the vanes 9a and 9b are arranged in the circumferential direction of the shoes 3a and 3b. It is rotatably accommodated in a fan-shaped space formed in the gap. The spigot portion 9c is coaxially fitted to the tip 2a of the camshaft 2, and the vane rotor 9 is integrally fixed to the camshaft 2 by bolts 15.

The vane rotor 9 and the camshaft 2 are positioned in the rotational angle direction by a knock pin 28. Cylindrical projection 5 fixed integrally with vane rotor 9
Are fitted to the inner peripheral wall of the front plate 4 so as to be relatively rotatable. As shown in FIG. 2, minute clearances 16 and 17 are provided between the outer peripheral wall of the vane rotor 9 and the inner peripheral wall of the shoe housing 3, and the vane rotor 9 is rotatable relative to the shoe housing 3.

A retard hydraulic chamber 10 is formed between the shoe 3a and the vane 9a, a retard hydraulic chamber 11 is formed between the shoe 3b and the vane 9b, and the shoe 3a and the vane 9b are formed.
And an advanced hydraulic chamber 13 is formed between the shoe 3b and the vane 9a.
The axial length of the vanes 9a and 9b is set slightly smaller than the axial length of the shoe housing 3 interposed between the front plate 4 and the chain sprocket 1.

With the above configuration, the camshaft 2 and the vane rotor 9 can rotate coaxially with respect to the chain sprocket 1, the shoe housing 3, and the front plate 4. As shown in FIG. 1, the stopper piston 7 as a contact portion is housed inside the vane 9 a of the vane rotor 9. The stopper piston 7 includes a small-diameter portion 7a and a large-diameter portion 7b.
c is formed in a slightly tapered shape as it goes in the direction opposite to the large-diameter portion 7b, that is, in the direction in which the stopper piston 7 fits into the stopper hole 20 as the abutted portion.

The large diameter portion 7b of the stopper piston 7 is accommodated in the accommodation hole 8 of the vane 9a, and is supported by the inner wall of the vane 9a forming the accommodation hole 8 so as to be slidable in the axial direction of the camshaft 2. I have. A spring 18 as an urging means is incorporated in the housing hole 8 on the right side in the axial direction of the stopper piston 7 shown in FIG. The guide ring 19 loosely fits or press-fits with the inner wall of the vane 9 a forming the accommodation hole 8, and loosely fits with the outer wall of the small diameter portion 7 a of the stopper piston 7.

Therefore, the stopper piston 7 is accommodated in the vane 9 a so as to be slidable in the axial direction of the camshaft 2, and is urged toward the front plate 4 by the spring 18.

As shown in FIG. 4, the taper angle of the tip 7c of the stopper piston 7 and the taper angle of the stopper hole 20 are set to be the same, and when the stopper piston 7 is fitted into the stopper hole 20, The tip end surface 7d of the stopper piston 7 does not contact the upper surface 20b of the stopper hole 20.

As shown in FIGS. 1 and 2, when the vane rotor 9 is at the most retarded position as the restraining position with respect to the shoe housing 3, the pressure oil has not yet been introduced into the hydraulic chambers 23 and 24. The stopper piston 7 is fitted in the stopper hole 20 by the urging force of the spring 18. At this time, the stopper 9e formed on the retard side of the vane 9b is in contact with the side surface of the shoe 3a, and the vane rotor 9 is directly receiving the driving force from the shoe housing 3.

Position of Stopper Piston 7 and Stopper Hole 2
The zero position is designed so that when the shoe housing 3 and the vane rotor 9 are at the most retarded position, these parts are pressed against each other.

That is, when the stopper 9e in FIG. 2 is at the most retarded position where it abuts against the side surface of the shoe 3a, the axis 100 of the stopper piston 7 is aligned with the axis 101 of the stopper hole 20.
In contrast, as shown in FIG. 4, the positions of both are designed in advance so as to fit eccentrically in the advance direction. When the stopper piston 7 is fitted into the stopper hole 20, the stopper piston 7 is brought into contact with the stopper hole 2 by the contact between the outer peripheral tapered surface of the stopper piston 7 and the inner peripheral tapered surface of the stopper hole 20.
0 works like a wedge, so the stopper piston 7
The vane rotor 9 and the shoe housing 3 are relatively moved in the rotational direction under the urging force in the axial direction of the rotor.

In the first embodiment, as shown in FIG. 4, the tapered surfaces come into contact with each other on the advance side opposite to the most retarded side as the restrained position. For this reason, the inclined surface of the tapered surface generates a biasing force in the rotation direction due to the axial biasing force of the stopper piston 7, and the vane rotor 9 is biased counterclockwise and the shoe housing 3 is biased clockwise in FIG. You.
Therefore, a biasing force for pressing the stopper portion 9e against the side surface of the shoe 3a is obtained, and the shoe housing 3 and the vane rotor 9 are firmly restrained.

The position of the stopper piston 7 and the position of the stopper hole 20 are set so that they abut on a predetermined side surface in the direction of rotation of the vane member and exhibit the wedge effect, even under manufacturing errors. Should be. As shown in FIG. 1, a drain hole 21 is provided in a side wall of the vane 9 a forming the accommodation hole 8 on the side of the chain sprocket 1, and when the vane rotor 9 is in the most retarded state, the air hole 22 of the chain sprocket 1 is formed. The position of the stopper piston 7, which is a part of the receiving hole 8, on the spring 18 side is equivalent to the atmospheric pressure since the position of the drain hole 21 substantially matches with the position of the drain hole 21.

As shown in FIG. 1, a hydraulic chamber 23 is formed between the guide ring 19 and the large diameter portion 7b of the stopper piston 7. A hydraulic chamber 24 is provided between the stopper hole 20 of the front plate 4 and the small diameter portion 7a of the stopper piston 7.
Is formed, and the hydraulic chamber 24 and the advance hydraulic chamber 13 communicate with each other through an oil passage 25 of the front plate 4.

As shown in FIGS. 1, 2 and 3, the vane rotor 9 has an oil passage 2 at a contact portion with the cylindrical projection 5.
9. An oil passage 30 is provided at a contact portion with the camshaft 2. The oil passage 29 communicates with the retard hydraulic chambers 10 and 11 by oil passages 31 and 32, and communicates with the hydraulic chamber 23 by an oil passage 33. The oil passage 30 communicates with the advance hydraulic chambers 12 and 13 by oil passages 34 and 35.

The oil passage 29 communicates with an oil passage 36, and the oil passage 36 communicates with an oil passage 39 formed in the camshaft 2 at an axial contact portion between the vane rotor 9 and the camshaft 2. are doing. The oil passage 30 communicates with an oil passage 38 formed in the camshaft 2 at an axial contact portion between the vane rotor 9 and the camshaft 2.

As shown in FIG. 1, the journal portion 42 of the camshaft 2 is rotatably supported by a bearing portion 41 provided on the cylinder head 40 and is restricted from moving in the direction of the rotation axis. Outer peripheral grooves 43 and 44 are provided in the circumferential direction of the outer peripheral wall of the journal portion 42. A supply oil passage 47 for pumping oil in the oil tank 45 by a pump 46 and a discharge oil passage 48 for discharging oil into the oil tank 45.
Is capable of selectively communicating with or blocking the outer peripheral grooves 43 and 44 by a switching operation of the switching valve 49. Pump 4
6 and the switching valve 49 constitute hydraulic drive means. In the present embodiment, the switching valve 49 is a known four-port guide valve.

As shown in FIG. 3, the outer circumferential groove 43 communicates with the oil passage 30 in the vane rotor 9 at the contact portion with the vane rotor 9 by the oil passages 37 and 38 in the camshaft 2. As shown in FIG. 1, the outer peripheral groove 44 is
The inner oil passage 39 communicates with an oil passage 36 in the vane rotor 9 at a contact portion with the vane rotor 9. With the above configuration, the pressure oil from the pump 46 is selectively supplied to the outer circumferential grooves 43 and 44 by the switching valve 49, and the retard hydraulic chambers 10 and 11 and the hydraulic chamber 23 and the advance hydraulic chambers 12 and 13 are provided.
In addition, it becomes possible to supply the pressure oil from the pump 46 to the hydraulic chamber 24 and to discharge the oil to the oil tank 45.

By making the clearance 16 of the outermost diameter portion of the vanes 9a and 9b minute, the circumferential length of the vanes 9a and 9b is relatively long, so that the retard hydraulic chamber 10 and the advance hydraulic chamber 13, communication between the retard hydraulic chamber 11 and the advance hydraulic chamber 12 via the clearance 16 is prevented as much as possible. A seal member 6 is mounted in the groove 9d of the vane rotor 9 in the minute clearance 17 formed at the smallest diameter portion of the shoes 3a and 3b, and the retard hydraulic chamber 10, the advance hydraulic chamber 12, and the retard hydraulic chamber are provided. 11 and advance hydraulic chamber 1
3 is prevented from communicating via the clearance 17 as much as possible.

Further, since the vane rotor 9 is relatively rotated with respect to the shoe housing 3, a sliding clearance is formed between both end surfaces of the vane rotor 9 in the axial direction and the inner surfaces of the shoe housing 3 and the chain sprocket 1. ing. Oil may leak between the hydraulic chambers from the sliding clearance. However, by making the axial length of the vane rotor 9 slightly smaller than the axial length of the shoe housing 3, both ends of the vane rotor 9 in the axial direction are reduced. The sliding clearance formed on the surface can be made minute.

Further, since the circumferential length of the vanes 9a and 9b is relatively long, that is, the cross-sectional area of the vanes 9a and 9b is large, oil leakage between the hydraulic chambers can be prevented as much as possible. For this reason, since the hydraulic pressure of each hydraulic chamber can be maintained at a predetermined value, the relative rotation of the vane rotor 9 with respect to the shoe housing 3 can be controlled with high accuracy. Further, since the cross-sectional area of the vanes 9a and 9b is large, the stopper piston 7 can be easily accommodated.

Next, the operation of the valve timing adjusting device will be described.

As shown in FIGS. 1 and 2, when the pressure oil from the pump 46 at the time of engine start has not yet been introduced into the hydraulic chambers 23 and 24, the vane rotor 9 moves the shoe housing 3 with the rotation of the crankshaft. The stopper 9e is in contact with the shoe 3a on the retard side at the most retarded position, and the rotational driving force is transmitted from the chain sprocket 1 to the camshaft 2 via the shoe housing 3 and the vane rotor 9.

The distal end 7c of the stopper piston 7 is fitted into the stopper hole 20 by the urging force of the spring 18 so that the tapered surface of the distal end 7c of the stopper piston 7 contacts the tapered surface of the stopper hole 20 on the advance side. By this fitting, the vane rotor 9 and the shoe housing 3 are urged in the turning direction and are firmly restrained. Therefore, even when a positive / negative reversal torque is generated in the camshaft 2 when driving at least one of the intake valve and the exhaust valve, the vane rotor 9 moves the shoe housing 3 toward the retard side and the advance side. By restricting the movement, no relative rotational vibration is generated, and occurrence of a tapping sound is prevented.

As shown in FIG. 5, the switching valve 49
When a is selected and pressure oil is pumped from the pump 46, the pressure oil is supplied to the retard hydraulic chambers 10 and 11 and the hydraulic chamber 23 through the outer peripheral groove 44 and the oil passages 39, 36, 29, 31, 32 and 33. Is introduced. The force received by the stopper piston 7 due to the oil pressure in the hydraulic chamber 23 depends on the pressure receiving area difference due to the diameter difference between the small diameter portion 7a and the large diameter portion 7b of the stopper piston 7, and the chain of the housing hole 8 is opposed to the urging force of the spring 18. It works in the direction of pushing the stopper piston 7 into the sprocket 1 side.

Then, the tip 7c of the stopper piston 7
Is completely removed from the stopper hole 20 of the front plate 4, so that the vane rotor 9 is released from the restraint with the shoe housing 3. However, the retard hydraulic chambers 10, 11
2 acts on the side surfaces of the vanes 9a and 9b, so that the vane rotor 9 is still held at the most retarded position shown in FIG. For this reason, generation of a tapping sound between the vane rotor 9 and the shoe housing 3 is prevented.

The oil slightly leaking from the retard hydraulic chambers 10, 11 to the advance hydraulic chambers 12, 13 is supplied to the oil passages 34, 35, 3
The oil is discharged from the switching valve 49 to the oil tank 45 through the 0, 38, 37 and the outer peripheral groove 43.

FIG. 5 when the switching valve 49a is selected.
From the state shown in FIG. 6, as shown in FIG.
When 9c is selected, the pressure oil from the pump 46
3. Introduced into the hydraulic advance chambers 12 and 13 via the oil passages 37, 38, 30, 34 and 35 and the hydraulic chamber 24 via the oil passage 25, and the retard hydraulic chambers 10 and 11 and the hydraulic chamber 23
Is opened to the oil tank 45.

At this time, since the oil pressure in the hydraulic chamber 23 is reduced to substantially the atmospheric pressure, the stopper piston 7 attempts to return to the stopper hole 20 by the spring 18, but the oil pressure in the hydraulic chamber 24 acts on the tip end surface 7d of the stopper piston 7. However, the stopper piston 7 remains pushed into the receiving hole 8 toward the chain sprocket 1 against the urging force of the spring 18.

Then, the hydraulic pressure in the advance hydraulic chambers 12 and 13 acts on the side surfaces of the vanes 9a and 9b, and the vane rotor 9 rotates clockwise with respect to the shoe housing 3, that is, in the advance direction. Timing is advanced. When the vane rotor 9 rotates with respect to the shoe housing 3, the circumferential position between the tip end portion 7c of the stopper piston 7 and the stopper hole 20 of the front plate 4 shifts, so that the stopper piston 7 does not fit in the stopper hole 20.

FIG. 7 shows a state in which the vane rotor 9 is most advanced with respect to the shoe housing 3. When the switching valve 49a is selected from the state of FIG. 7, the vane rotor 9 rotates counterclockwise with respect to the shoe housing 3 in the X direction of FIG. 1, that is, in the retard direction, and the valve timing of the camshaft 2 is delayed. Is done.

If the switching valve 49b is selected while the vane rotor 9 is rotating with respect to the shoe housing 3 in the advance direction or the retard direction, the retard hydraulic chambers 10 and 11 are selected.
The inflow and outflow of the oil in the advance hydraulic chambers 12 and 13 are blocked, and the vane rotor 9 is held at an intermediate position, so that a desired valve timing can be obtained. As described above, the stopper piston 7 fits into the stopper hole 20 of the front plate 4 when the vane rotor 9 is at the most retarded position with respect to the shoe housing 3 and no pressure oil is introduced, and the pressure oil is When it is introduced, it does not fit in the stopper hole 20.

In the first embodiment of the present invention described above,
The direct contact between the housing member and the vane member is enhanced by the wedge effect by the contact of the tapered surface between the stopper hole 20 and the stopper piston 7, so that the housing member and the vane member are coaxially aligned. Thus, the housing member and the vane member can be firmly restrained.

Further, since the tip end portion 7c of the stopper piston 7 is tapered and the stopper piston 7 can be displaced in the axial direction, even if the stopper piston 7 and the stopper hole 20 are misaligned due to a manufacturing error, the stopper piston 7 can be moved. The piston 7 can be securely fitted into the stopper hole 20. (Second Embodiment) FIGS. 9 and 10 show a second embodiment of the present invention. In the second embodiment, a stopper piston 5 is used instead of the stopper piston 7 as the contact portion of the first embodiment.
0, and the guide ring 51 is used instead of the guide ring 19.
Is housed inside the vane 9a. In addition, components that are substantially the same as those in the first embodiment are denoted by the same reference numerals.

FIG. 9 shows a state in which the stopper piston 50 is fitted in the stopper hole 20 of the front plate 4, and FIG. 10 shows a state in which pressure oil is introduced into the hydraulic chamber 23 and the stopper piston 50 comes out of the stopper hole 20. .

The stopper piston 50 includes a small diameter portion 50a, a medium diameter portion 50b, and a large diameter portion 50c, and the guide ring 51 includes a small inside diameter portion 51a and a large inside diameter portion 51b. The guide ring 51 is fixed to the vane rotor 9 by press fitting or the like, and the stopper piston 50 is slidable with respect to the guide ring 51. Stopper piston 50
A substantially sealed annular damper chamber 52 which is a fluid damper is formed by the outer peripheral wall of the small diameter portion 50a and the intermediate diameter portion 50b and the inner peripheral wall of the guide ring 51.

As shown in FIG. 9, in a state where the pressurized oil has not yet been supplied from the pump 46 to the hydraulic chamber 23 or 24 immediately after the start of the engine, the vane rotor 9 is at the most retarded position with respect to the shoe housing 3, and The piston 50 is fitted into the stopper hole 20 by the urging force of the spring 18 and connects the front plate 4 and the vane rotor 9.

From the state shown in FIG.
When a is selected, pressurized oil is supplied to the hydraulic chamber 23, and FIG.
The stopper piston 50 comes out of the stopper hole 20 as shown in FIG. 9 and 10 both show a state in which the vane rotor 9 is at the most retarded position with respect to the shoe housing 3. FIG. When the pressure oil is supplied to the hydraulic chamber 23, the inside of the damper chamber 52 is filled with the oil through the fitting clearance between the stopper piston 50 and the guide ring 51.

When selecting the switching valve 49c from the state shown in FIG. 10 and trying to rotate the vane rotor 9 with respect to the shoe housing 3 in the advance direction, even if the switching valve 49 is switched, the hydraulic chamber 24 is switched over. A slight time delay occurs until the oil pressure reaches the predetermined value. Then spring 1
8 causes the stopper piston 50 to move into the stopper hole 2
It may move in the direction of fitting to zero. Even if the stopper piston 50 attempts to move in the fitting direction with the stopper hole 20, the oil in the damper chamber 52 is only slightly discharged from the fitting clearance, so that the moving speed of the stopper piston 50 in the fitting direction is reduced. So that the damper room 52
Works.

Since the oil pressure in the hydraulic chamber 24 reaches a predetermined value before the stopper piston 50 is fitted into the stopper hole 20, the shoe housing 3 by the hydraulic pressure is not fitted to the stopper piston 50. , The relative rotation control of the vane rotor 9 can be continued.

In the second embodiment, during the transitional period in which the vane rotor 9 moves from the most retarded position to the shoe housing 3 in the advance direction, the stopper piston 50 is moved.
Can be reliably prevented from being momentarily pushed into the stopper hole 20.

As another embodiment of the present invention, in the first embodiment or the second embodiment, the hydraulic chamber 23 is communicated with the advance hydraulic chambers 12 and 13 and the hydraulic chamber 24 is connected to the retard hydraulic chamber 1.
The same effects as those of the first embodiment or the second embodiment can be obtained even when the communication is made with 0 and 11. (Third Embodiment) FIGS. 11 and 12 show a third embodiment of the present invention.

The stopper hole 60 shown in FIGS.
The configuration other than the shape is substantially the same as that of the first embodiment. FIG. 11 shows the fitting state of the stopper piston 7 and the stopper hole 60 in the radial direction of the camshaft. The outer peripheral surface of the stopper piston 7 and the inner peripheral surface of the fitting hole 60 are in front of the drawing. In contact.

As shown in FIG. 12, the cross-sectional shape of the stopper hole 60 is formed in the shape of a long hole in the vertical direction of FIG. 12, that is, in the radial direction of the front plate 4. Therefore,
The stopper hole 60 as an abutted portion has an elliptical shape along a central axis 60c extending in a radial direction, and an inner peripheral surface thereof is formed in a tapered shape. The outer peripheral surface of the distal end portion 7c of the stopper piston 7 as a contact portion is formed in a tapered circular cross section.

Further, as in the first embodiment, the position of the stopper piston 7 and the position of the stopper hole 60 are determined when the shoe housing 3 and the vane rotor 9 are at the most retarded position as the restraining position. Since they are designed to be pressed against each other, the shoe housing 3 and the vane rotor 9 are firmly restrained.

Further, since the stopper hole 60 is formed in an oval shape in the radial direction, when the stopper piston 7 is fitted into the stopper hole 60, the two tapered surfaces in the radial direction come into contact with each other, and the front plate 4 is moved in the radial direction. Biasing is prevented.
As a result, a biased force is prevented from being applied to the sliding portion between the front plate 4 and the cylindrical protruding portion 5 which is designed to have a clearance as small as possible, and uneven wear is prevented. Similarly, it is possible to prevent a radial displacement between the housing member including the front plate 4 and the vane member including the vane rotor 9, and to prevent uneven wear between the two members as well as between the two members. Prevention of deterioration in sealing performance is achieved.

As described above, in the third embodiment, even if a force for firmly restraining the housing member and the vane member is generated, the stopper hole 60 is made oblong in the radial direction, and the stopper piston 7 and the stopper hole 60 are connected to each other. Since the contact is limited to the rotation direction of the vane rotor 9, it is possible to prevent an unnecessary radial force from acting between the housing member and the vane member.
Therefore, the housing member and the vane member can be firmly restrained while the housing member and the vane member are coaxially aligned. (Fourth Embodiment) FIGS. 13 and 14 show a fourth embodiment of the present invention. Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals. In the fourth embodiment, instead of the drain hole 21 provided in the side wall of the vane 9a on the side of the chain sprocket 1 in the first embodiment and the air hole 22 provided in the chain sprocket 1, the drain hole 7 is provided in the outer peripheral wall of the vane 9a.
1 is provided, and an air hole 72 is provided on the outer peripheral wall of the shoe housing 3. The drain hole 71 and the atmosphere hole 72 communicate with each other to form a communication hole, and the back pressure chamber 8a, which is the accommodation hole 8 on the side of the chain sprocket 1, can be opened to the atmosphere.

The volume of the back pressure chamber 8a is
Decreases when the stopper piston 7 moves in the rightward direction in FIG. 13, that is, in the direction of releasing the restraint between the shoe housing 3 and the vane rotor 9, and increases when the stopper piston 7 moves in the leftward direction in FIG. I do.

As shown in FIG. 13, when the vane rotor 9 is at the most retarded position with respect to the shoe housing 3 and no pressure oil is supplied to the hydraulic chambers 23 and 24, the stopper piston 7 is fitted into the stopper hole 20. , The drain hole 71 and the air hole 72 are almost in the same position and communicate with each other.

When pressure oil is supplied to the hydraulic chamber 23 from the state shown in FIG.
Escapes from the stopper hole 20, and the drain hole 71 is closed by the outer wall of the large diameter portion 7b, so that the back pressure chamber 8a is disconnected from the atmosphere. FIGS. 13 and 14 both show a state in which the vane rotor 9 is at the most retarded position with respect to the shoe housing 3.

When the vane rotor 9 is to be rotated in the advance direction with respect to the shoe housing 3 from the state shown in FIG. 14, even if the switching valve (not shown) is switched, the oil pressure in the hydraulic chamber 24 becomes slightly lower than the predetermined value. Time delay occurs. At this time, even if the stopper piston 7 attempts to move in the direction in which the stopper piston 20 is fitted by the biasing force of the spring 18, the communication with the atmosphere is interrupted and the back pressure chamber 8a is closed. The moving speed in the direction is reduced.

Therefore, before the stopper piston 7 is fitted into the stopper hole 20, the oil pressure in the hydraulic chamber 24 reaches a predetermined value. The advance rotation of the vane rotor 9 can be started.

In the above-described embodiment of the present invention,
Although both the distal end of the stopper piston and the stopper hole are formed with tapered surfaces, only one of them may be formed as a tapered surface. For example, one is a tapered surface,
The other may be formed with a spherical surface that can slide on the tapered surface. Further, since it is important to have a slope in order to generate a biasing force in the rotation direction due to the wedge effect, the stopper hole is formed in a shape having a slope only on at least one of the rotation direction sides, for example, only on the advance side. May be.

In the above embodiment, the most retarded position is set as the restraint position, and as shown in FIG.
In this case, the stopper 9e on the most retarded side may be provided on the left side of the vane 9a in FIG. 2 to make contact with the shoe 3b. Also in this case, a force for pressing the vane rotor 9 against the shoe housing 3 can be obtained by the contact between the stopper piston and the stopper hole on the advance side tapered side surface, and both can be firmly restrained.

In the above embodiment, the stopper piston and the stopper hole are designed to abut only on the advance side, which is one of the vane rotor rotation directions, that is, only on the side opposite to the restraining position, and the rotating power due to the wedge effect is obtained. Is generated to restrain the housing member and the vane member. However, the stopper piston and the stopper hole abut in both directions of rotation, and the housing member and the vane member are abutted only by the stopper piston and the stopper hole. May be restricted. In this case, a high strength is required for the stopper piston. Also in this case, it is desirable that the stopper hole is formed in an oblong shape in the radial direction, and that the contact of the tapered surface is limited only to the side surface in the rotation direction.

In the above embodiment, the taper angle of the stopper piston and the taper angle of the stopper hole are the same, but if the stopper piston can be fitted into the stopper hole, the taper angle of the stopper piston and the taper angle of the stopper hole The angles need not be the same.

In the above embodiment, the chain sprocket is rotated with the crankshaft as the drive shaft, the shoe housing as a housing member fixed thereto is rotated with the crankshaft, and the vane rotor is rotated with the camshaft as the driven shaft. However, it is also possible to rotate the chain sprocket with the camshaft and rotate the vane rotor with the crankshaft. In this case, the vane rotor is restrained at the most advanced position with respect to the shoe housing.

Further, in the above embodiment, in an engine in which two camshafts for opening and closing an intake valve and a camshaft for opening and closing an exhaust valve are provided in parallel, a valve timing adjusting device is provided between the two camshafts. May be interposed. For example, in the case where one camshaft rotated synchronously by a chain or the like from a crankshaft is used as a drive shaft, and the other camshaft is used as a driven shaft by a transmission means such as a gear, the one cam that uses a vane rotor as a drive shaft The housing member may be rotated with the shaft, and the housing member may be rotated with the other camshaft, which is the driven shaft, or vice versa.

In the above embodiment, the vane rotor is provided with two vanes. However, the number of vanes may be one or three or more.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line II of FIG. 2 showing a valve timing adjusting device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the valve timing adjusting device according to the first embodiment of the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a longitudinal sectional view showing a state where the stopper piston of the first embodiment has come out of the stopper hole.

FIG. 6 is a longitudinal sectional view showing a state in which a vane rotor rotates in an advance direction with respect to the shoe housing of the first embodiment.

FIG. 7 is a cross-sectional view showing the first embodiment in the state of FIG. 6;

FIG. 8 is a schematic diagram showing a hydraulic circuit according to the first embodiment.

FIG. 9 is a longitudinal sectional view showing a valve timing adjusting device according to a second embodiment of the present invention.

FIG. 10 is a longitudinal sectional view showing a state in which a stopper piston of a second embodiment has come out of a stopper hole.

FIG. 11 is a cross-sectional view illustrating a fitted state of a stopper piston and a stopper hole according to a third embodiment.

FIG. 12 is a sectional view taken along line XII-XII of FIG.

FIG. 13 is a longitudinal sectional view showing a valve timing adjusting device according to a fourth embodiment of the present invention.

FIG. 14 is a longitudinal sectional view showing a state where a stopper piston according to a fourth embodiment has come out of a stopper hole.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chain sprocket (housing member) 2 Camshaft (driven shaft) 3 Shoe housing (housing member) 3a, 3b Shoe 4 Front plate (housing member) 7 Stopper piston (contact part) 7c Tip 8a Back pressure chamber 9 Vane rotor ( Vane member 9a, 9b Vane 20 Stopper hole (contacted part) 46 Pump (drive means) 49 Switching valve (drive means) 50 Stopper piston (contact part) 60 Stopper hole (contacted part)

Claims (7)

[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 together with one of the drive shaft and the other of the drive shaft and the driven shaft, and rotates relative to the housing member only within a predetermined angular range in a housing chamber formed in the housing member. And a contact portion provided on the housing member and the vane member, the contact members being in contact with each other and restricting the movement of the housing member and the vane member in the rotational direction at a predetermined constraint position. And a contacted part, wherein the restrained state can be released by displacement of the contacted part, and the contacting part is attached in a direction of contact with the contacted part. A restraining means including a biasing means to perform the displacement of the contact portion against the biasing means by a fluid pressure to release the restraint between the housing member and the vane member, and the housing member by a fluid pressure. And a fluid-driven driving means for relatively rotating the vane member and the vane member, wherein the abutting portion receives the fluid pressure supplied from the driving means and restrains the housing member and the vane member. And the first fluid pressure supplied from the driving means acts to rotate the vane member relative to the housing member in the advance direction to release the restrained state, The second fluid pressure supplied from the driving means acts to rotate the vane member relative to the housing member in the retard direction to release the restrained state. A valve timing adjusting device for an internal combustion engine, which is configured as described above. 2. A driving force transmission system for transmitting driving force from a driving shaft of an internal combustion engine to a driven shaft for opening and closing 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 together with one of the drive shaft and the other of the drive shaft and the driven shaft, and rotates relative to the housing member only within a predetermined angle range in a housing chamber formed in the housing member. And a contact portion provided on the housing member and the vane member, the contact members being in contact with each other and restricting the movement of the housing member and the vane member in the rotational direction at a predetermined constraint position. And a contacted part, wherein the restrained state can be released by displacement of the contacted part, and the contacting part is attached in a direction of contact with the contacted part. A restraining means including a biasing means to perform the displacement of the contact portion against the biasing means by a fluid pressure to release the restraint between the housing member and the vane member, and the housing member by a fluid pressure. And a fluid-driven driving unit for relatively rotating the vane member and the vane member. First and second pressure receiving surfaces to be released; a first fluid pressure supplied from the driving means on the first pressure receiving surface so as to relatively rotate the vane member relative to the housing member in an advance direction; The second fluid pressure supplied from the driving means acts on the second pressure receiving surface so as to relatively rotate the vane member in the retard direction with respect to the housing member. A valve timing adjusting device for an internal combustion engine, which is configured to release a restrained state. 3. Between the contact portion and the contacted portion,
The valve timing adjusting device for an internal combustion engine according to claim 1 or 2, wherein a fluid damper for reducing a displacement speed of the contact portion is formed by an internal working fluid. 4. The contact portion has a back pressure chamber whose volume is reduced in accordance with displacement of the contact portion in the constraint release direction. The valve timing adjusting device for an internal combustion engine according to any one of claims 1 to 3, wherein a communication hole with the outside is closed. 5. The device according to claim 1, wherein the abutting portion and the abutted portion are configured to abut when the driven shaft is in a most retarded state in which the driven shaft is most retarded. 5. The valve timing adjusting device for an internal combustion engine according to any one of 4. 6. A vane-type valve timing adjusting device for an internal combustion engine, comprising: a contact portion for restricting a rotational movement of a housing member and a vane member at a predetermined constraint position; and a contacted portion.
The contact portion is driven and held toward an unconstrained state by both the first fluid pressure for changing the valve timing to the advance side and the second fluid pressure for changing the valve timing to the retard side. Timing adjustment device for an internal combustion engine. 7. A vane-type valve timing adjusting device for an internal combustion engine, comprising: a contact portion for restricting a rotational movement of a housing member and a vane member at a predetermined restriction position; and a contacted portion.
The contact portion is always in an unconstrained state when either one of the first fluid pressure for changing the valve timing to the advance side and the second fluid pressure for changing the valve timing to the retard side is supplied. A valve timing adjusting device for an internal combustion engine, characterized by holding.