JP4807387B2 - Valve timing control device - Google Patents

Description

  The present invention relates to a valve opening / closing timing control device used for controlling the opening / closing timing of an exhaust valve or an intake valve in a valve operating apparatus for an internal combustion engine.

  As one example of this type of valve opening / closing timing control device, for example, Japanese Utility Model Laid-Open No. 2-50105 discloses a rotation that is mounted on a rotary shaft for valve opening / closing so as to be relatively rotatable within a predetermined range and to which rotational power from a crank pulley is transmitted. A transmission member, a vane attached to the rotating shaft (consisting of a camshaft and an internal rotor provided integrally therewith), and an advance angle formed by the vane formed between the rotating shaft and the rotation transmitting member. A fluid pressure chamber divided into a chamber and a retardation chamber; a first fluid passage for supplying and discharging fluid to the advance chamber; and a second fluid passage for supplying and discharging fluid to the retardation chamber; A retraction hole for accommodating a lock pin formed in the rotation transmission member and spring-biased toward the rotation shaft inside, and a relative phase between the rotation shaft and the rotation transmission member formed in the rotation shaft is a predetermined phase. The head of the lock pin when synchronized with A receiving hole to be fitted, that a third fluid passage for supplying and discharging fluid is disclosed in the receiving hole.

  In the valve timing control device disclosed in the above publication, the third fluid passage for supplying and discharging fluid to the receiving hole is connected to the first fluid passage for supplying and discharging fluid to the advance chamber and is always in communication. Therefore, when the fluid is supplied to the advance chamber through the first fluid passage and the fluid is discharged from the retard chamber through the second fluid passage, the fluid is also supplied to the receiving hole from the first fluid passage through the third fluid passage. Then, after the lock pin is retracted into the retraction hole against the spring biasing force and the lock pin head is released from the receiving hole and unlocked by the lock pin, the rotation shaft is advanced with respect to the rotation transmission member. Rotate to the side. When the fluid is supplied to the retarding chamber through the second fluid passage and the fluid is discharged from the advance chamber through the first fluid passage, the rotating shaft relatively rotates to the retarding side with respect to the rotation transmitting member and is received. The fluid is also discharged from the hole through the first fluid passage from the third fluid passage, the lock pin is pushed by the spring biasing force, and when the relative phase of the rotation shaft and the rotation transmission member is synchronized at a predetermined phase, The head is inserted into the receiving hole by the biasing force of the spring and locked (relative rotation of the rotating shaft and the rotation transmitting member is restricted).

  By the way, in the valve opening / closing timing control device disclosed in the above publication, the lock pin repeats the releasing operation and the locking operation every time the valve opening / closing timing is controlled by the device, and the durability of the lock by the lock pin is repeated. There is a risk of problems in reliability. Further, since the third fluid passage communicates with the first fluid passage, when the position where the lock pin is engaged with the receiving hole is set to the intermediate position between the most advanced position and the most retarded position, the lock is locked. It is necessary to perform complex fluid pressure control for pin release.

The object of the present invention is to restrict unnecessary relative rotation of the rotating shaft and the rotation transmitting member when the internal combustion engine is started (when rotation is unstable and rotational fluctuation is large). Focusing on the above-mentioned problems, the vane attached to the internal rotor that rotates integrally with the rotary shaft for opening and closing the valve of the internal combustion engine and the internal rotor can rotate relative to each other within a predetermined range. An external rotor which forms a fluid pressure chamber divided into an advance angle chamber and a retard angle chamber by the vane and is rotated by power transmitted from a crank pulley of the internal combustion engine, A first fluid passage for supplying and discharging fluid to the advance chamber, a second fluid passage for supplying and discharging fluid to the retard chamber, and a retraction hole formed in the external rotor, To the outer surface The inner rotor is formed so that the head of the lock pin is fitted when the relative phase between the spring-biased lock pin and the inner rotor and the outer rotor is synchronized with a predetermined phase when the internal combustion engine is started. and receiving hole, Bei example a pilot passage supplying the fluid to the lock pin in the receiving hole for unlocking is retracted to the retracted hole from said receiving bore, said evacuation the head of the locking pin advances or retreats A communication groove for always communicating the end of the hole and the receiving hole is provided, and the lock pin is held in the retracted position by the pressure of oil supplied through the pilot passage regardless of the relative phase of the inner rotor and the outer rotor. It is an object of the present invention to provide a valve opening / closing timing control device that is characterized by the above.

In the valve opening and closing timing control device according to the present invention, by providing a communication passage that always communicates the end of the retraction hole with which the head of the lock pin advances and retreats and the receiving hole,
Regardless of the relative phase of the rotation shaft and the rotation transmission member, fluid can be always supplied to the lock pin through the pilot passage and the communication passage, and the lock pin can be held in the retraction hole. Unnecessary movement can be prevented.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The valve opening / closing timing control apparatus according to the present invention shown in FIGS. 1 to 4 includes a rotary shaft for valve opening / closing composed of a camshaft 10, an internal rotor 30 and a vane 50 attached to the internal rotor 30, and a predetermined rotational shaft. The outer rotor 40, the lock pin 60, and the timing pulley 70, which are externally rotatably mounted in a range, are configured by a rotation transmission member such as a timing pulley 70, and the outer periphery of the camshaft 10 rotates to the cylinder head 81 of the internal combustion engine via a bearing 80. It is supported freely. The bearing 80 is fixed to the cylinder head 81. Further, as is well known, the timing pulley 70 is configured to transmit rotational power in the clockwise direction of FIG. 1 from a crank pulley via a timing belt (both not shown).

  The camshaft 10 has a known cam (not shown) that opens and closes an intake valve or an exhaust valve (not shown). As shown in FIGS. 2 and 3, the camshaft 10 has an axial direction inside the camshaft 10. An advance passage 11, a retard passage 12, and a pilot passage 13 are provided. The advance passage 11 is connected to the connection port 101 of one switching valve 100 through an annular passage 91 and a connection passage 92 provided on the inner peripheral side of the bearing 80. The retard passage 12 is connected to the connection port 102 of the switching valve 100 through an annular passage 93 and a connection passage 94 provided on the inner peripheral side of the bearing 80. The pilot passage 13 is connected to the connection port 111 of the other switching valve 110 via an annular passage 95 and a connection passage 96 provided on the inner peripheral side of the bearing 80.

  One switching valve 100 is controlled in switching operation by a control device (not shown), and is oil driven by the internal combustion engine in the state where the switching valve 100 is switched to the retard position shown in FIGS. The supply port 103 connected to the pump 120 is connected to and communicated with the connection port 102, and the connection port 101 is connected to and communicated with the discharge port 104 connected to the reservoir 130. In the state switched to the position, the supply port 103 is connected to the connection port 101 for communication, and the connection port 102 is connected to the discharge port 104 for communication. Therefore, oil is supplied from the oil pump 120 to the advance passage 11 in the state of the advanced angle position, and oil is discharged from the retard angle passage 12 to the reservoir 130. In the state of the retard position, the oil pump 120 delays the oil. Oil is supplied to the passage 12 and discharged from the advance passage 11 to the reservoir 130.

  The other switching valve 110 has its switching operation controlled by a control device (not shown), and the connection port 111 is connected to the oil pump 120 in the state where the switching position is switched to the supply position shown in FIGS. The connection port 111 is connected to the supply port 112 and connected to the discharge port 113, and the communication with the discharge port 113 connected to the reservoir 130 is blocked. The communication with 112 is blocked and connected to the discharge port 113 for communication. Therefore, oil is supplied to the pilot passage 13 in the supply position, and oil is discharged from the pilot passage 13 to the reservoir 130 in the discharge position.

  The internal rotor 30 is integrally fixed to the camshaft 10 by bolts 19 and has vane grooves 31 for attaching the five vanes 50 in the radial direction, as shown in FIGS. That is, when the relative phases of the rotation shafts such as the camshaft 10 and the internal rotor 30 and the rotation transmission member such as the external rotor 40 and the timing pulley 70 are synchronized at a predetermined phase, the receiving hole 32 into which a predetermined amount of the head of the lock pin 60 is inserted. A connection passage 33 that connects the bottom of the receiving hole 32 and the pilot passage 13, a connection passage 34 that connects the advance chamber R1 and the advance passage 11 defined by the vanes 50, an annular passage 35, and a diameter. Direction passage 36 (see FIG. 1) and a connecting passage 37 (see FIG. 2) connecting the retardation chamber R2 and the retardation passage 12 defined by the vanes 50. . Each vane 50 is urged radially outward by a spring (not shown) housed in the bottom of the vane groove 31.

  The outer rotor 40 is assembled to the outer periphery of the inner rotor 30 so as to be relatively rotatable within a predetermined range, and side plates 41 and 42 are integrally connected to both sides by bolts 43, and timing pulleys are connected thereto. 70 are integrally connected by bolts 44. Also, the outer rotor 40 is formed with a recess 45 that accommodates each vane 50 and forms the working chamber Ro divided by the vane 50 into the advance chamber R1 and the retard chamber R2 by the inner rotor 30. In addition, a retraction hole 46 that accommodates the lock pin 60 and a spring 61 that biases the lock pin 60 toward the inner rotor 30 is formed in the radial direction of the outer rotor 40.

  The lock pin 60 is fitted in the retraction hole 46 so as to be movable in the radial direction of the external rotor 40, and is urged toward the internal rotor 30 by a spring 61. The spring 61 is a compression spring interposed between the lock pin 60 and the retainer 62, and the retainer 62 is retained by a clip 63 assembled to the external rotor 40.

  In the valve timing control apparatus of the present embodiment configured as described above, the lock pin 60 locks in the state shown in FIGS. 1 to 4 (the most retarded state in which the volume of the advance chamber R1 is minimized). When oil is supplied from the oil pump 120 through the switching valve 110 and the pilot passage 13 to the receiving hole 32 in the state where the lock pin 60 is opposed to the spring 61, as shown in FIG. It is pushed and removed from the receiving hole 32 and retracted into the retracting hole 46. For this reason, the lock by the lock pin 60 is released, and the camshaft 10, the internal rotor 30 and the vane 50 and other rotational shaft side members rotate relative to the external rotor 40 and the timing pulley 70 and other rotational transmission members in the clockwise direction of FIG. It becomes possible.

  Further, the oil pump 120 is switched to the advance position in the state shown in FIG. 5 (the state in which the lock by the lock pin 60 is released in the most retarded state where the volume of the advance chamber R1 is minimized). When oil is supplied to the advance chamber R1 through the switching valve 100 and the advance passage 11 and the oil is discharged from the retard chamber R2 to the reservoir 130, the camshaft 10, the internal rotor 30 and the vane 50 are discharged. The state shown in FIG. 6 when the constant rotation shaft side member rotates relative to the rotation transmission member such as the external rotor 40 and the timing pulley 70 in the clockwise direction of FIG. 5, that is, the volume of the retardation chamber R2 is minimized. It becomes an advance angle state. In the state shown in FIG. 6, the receiving hole 32 is not in direct communication with the retraction hole 46, so that the oil in the retraction hole 46 leaks through the gap between the inner rotor 30 and the outer rotor 40. The lock pin 60 is pushed by the spring 61 and comes into slidable contact with the outer peripheral surface of the inner rotor 30.

  Further, the oil pump 120 is switched to the retard position in the state shown in FIG. 6 (the state where the lock pin 60 is unlocked at the most advanced angle where the volume of the retard chamber R2 is minimized). When oil is supplied to the retarding chamber R2 through the switching valve 100 and the retarding passage 12 and the oil is discharged from the advance chamber R1 to the reservoir 130, the camshaft 10, the internal rotor 30 and the vane 50 are discharged. 6 is rotated counterclockwise in FIG. 6 with respect to the rotation transmission member such as the external rotor 40 and the timing pulley 70, and the volume of the advance chamber R1 is minimized. It becomes the most retarded state. When the transition from the state shown in FIG. 6 to the state shown in FIG. 5 is made, the receiving hole 32 changes from a state not directly communicating with the retraction hole 46 to a state directly communicating with the retreating hole 46. The lock pin 60 is pushed against the spring 61 by the oil to be retracted into the retracting hole 46 of the external rotor 40 and is not in contact with the outer peripheral surface of the internal rotor 30.

  By the way, in the valve timing control apparatus of this embodiment, the oil supply / discharge from the oil pump 120 to the advance passage 11 or the retard passage 12 is switched by the switching valve 100, and from the oil pump 120 to the pilot passage 13. The oil supply / discharge of the oil is switched by the switching valve 110, and the oil supply / discharge of the pilot passage 13 is performed independently of the oil supply / discharge of the advance passage 11 and the retard passage 12. Therefore, for example, the oil is steadily passed from the oil pump 120 to the receiving hole 32 through the pilot passage 13 except for the time when the rotation is particularly unstable during the drive from the start to the stop of the internal combustion engine (a predetermined time immediately after the start). And the reservoir 13 through the receiving hole 32 for a predetermined time immediately after starting the internal combustion engine and when the internal combustion engine is stopped. Oil can be can be discharged to.

  Therefore, when the internal combustion engine is driven, the head of the lock pin 60 can be retracted from the receiving hole 32 to the retracting hole 46 at a time excluding a predetermined time immediately after starting, and the lock by the lock pin 60 can be maintained in a released state. In addition, the head of the lock pin 60 can be fitted into the receiving hole 32 for a predetermined time immediately after the start of the internal combustion engine and when the internal combustion engine is stopped, and the lock pin 60 can be maintained in the locked state. In such a case, the unlocking operation of the lock pin 60 can be performed only after a lapse of a predetermined time immediately after starting the internal combustion engine, and the lock operation can be performed only when the internal combustion engine is stopped. The number of repetitions of insertion / retraction into the hole 32 can be greatly reduced, and the durability and reliability of the lock by the lock pin 60 can be greatly improved.

  It is also possible to directly connect the connection ports 111 and 112 without using the switching valve 110. In particular, in this case, as in the present embodiment, the position of the receiving hole 32 is set to a position where the lock pin 60 is engaged when the volume of the retardation chamber R2 is maximized (the state of the most retarded position). It is effective when provided. That is, when the internal combustion engine is driven, the rotation of a crankshaft (not shown) is transmitted in the order of the timing pulley 70, the external rotor 40, the vane 50, the internal rotor 30, and the camshaft 10, so that the vane 50 is always attached to the retard side. Be forced. On the other hand, when the driving of the internal combustion engine is stopped, the oil pressure in the advance angle chamber R1 and the retard angle chamber R2 decreases with time. When the internal combustion engine is started in this state, since the oil pressure from the oil pump 120 to the advance chamber R1 and the retard chamber R2 is not satisfied, the vane 50 comes into contact with the external rotor 40 to generate a hitting sound. To do. In order to prevent this hitting sound, the lock pin 60 has an inner rotor 30 and an outer rotor 40 at least for a predetermined time immediately after the start of the internal combustion engine (until the oil pressure from the oil pump 120 is sufficiently filled). By restricting the relative rotation of the blades, the hitting sound by the vane 50 is prevented. However, the switching valve 110 connects the connection ports 111 and 112 to supply oil to the pilot passage 13 after a predetermined time immediately after the internal combustion engine starts, and during the predetermined time immediately after the internal combustion engine starts. Since sufficient oil pressure from the oil pump 120 cannot be obtained, the switching valve 110 can be eliminated by directly connecting the connection ports 111 and 112.

  FIG. 7 shows another embodiment of the present invention. In this embodiment, a communication groove 47 extending in the rotation direction is formed on one side of the inner peripheral side end of the retraction hole 46, and this communication is shown. The groove 47 allows the inner peripheral side end of the retraction hole 46 in which the head of the lock pin 60 advances and retreats and the receiving hole 32 to always communicate with each other. Therefore, regardless of the relative phase of the rotation shaft side member such as the camshaft 10, the inner rotor 30 and the vane 50 and the rotation transmission member such as the outer rotor 40 and the timing pulley 70, the receiving hole 32 is directed to the lock pin 60 through the communication groove 47. Thus, the oil can be always supplied, the lock pin 60 can be held in the retracted state in the retracting hole 46, and unnecessary movement of the lock pin 60 (the movement shown in FIG. 6) can be prevented. Thus, for example, it is possible to eliminate the generation of a hitting sound caused when the lock pin 60 comes into contact with the outer peripheral surface of the inner rotor 30.

  In each of the above embodiments, the vane 50 is attached to the internal rotor 30 and the lock pin 60 and the spring 61 are accommodated in the external rotor 40. However, the lock pin and the spring 61 are accommodated in the internal rotor and the vane is accommodated in the external rotor. It is also possible to carry out by attaching.

It is a figure which shows roughly one Embodiment of the valve opening / closing timing control apparatus by this invention, and is a front view which shows the relationship between an internal rotor, an external rotor, a vane, a lock pin, a timing pulley, etc. It is a figure which shows schematically one Embodiment of the valve timing control apparatus by this invention, and is sectional drawing along the 2-2 line of FIG. It is a figure which shows schematically one Embodiment of the valve timing control apparatus by this invention, and is sectional drawing which followed the 3-3 line of FIG. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. It is sectional drawing which shows the state which the lock pin evacuated from the state shown in FIG. FIG. 6 is a cross-sectional view illustrating a state in which the rotary shaft side member is rotated by a predetermined amount relative to the rotation transmission member in the clockwise direction from the state illustrated in FIG. 5. It is sectional drawing which shows the state substantially equivalent to FIG. 6 in other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Camshaft, 11 ... Advance angle channel | path (1st fluid channel), 12 ... Delay angle channel | path (2nd fluid channel), 13 ... Pilot channel | path (3rd fluid channel), 30 ... Internal rotor, 32 ... Receiving hole, DESCRIPTION OF SYMBOLS 40 ... External rotor, 46 ... Retraction hole, 47 ... Communication groove (communication path), 50 ... Vane, 60 ... Lock pin, 61 ... Spring, 70 ... Timing pulley, 100, 110 ... Switching valve, Ro ... Working chamber (fluid) Pressure chamber), R1 ... advance angle chamber, R2 ... retard angle chamber.

Claims (3)

A vane attached to an internal rotor that rotates integrally with a rotary shaft for opening and closing a valve of an internal combustion engine;
A fluid pressure chamber, which is assembled to the inner rotor so as to be relatively rotatable within a predetermined range and is divided into an advance chamber and a retard chamber by the vane, is formed therein, and the crank pulley of the internal combustion engine An external rotor that is rotated by the power transmitted from
A first fluid passage for supplying and discharging fluid to the advance chamber;
A second fluid passage for supplying and discharging fluid to the retardation chamber;
A lock pin housed in a retraction hole formed in the outer rotor and spring-biased toward the outer peripheral surface of the inner rotor;
A receiving hole formed in the internal rotor so that the head of the lock pin is fitted when the relative phase between the internal rotor and the external rotor is synchronized with a predetermined phase when the internal combustion engine is started,
E Bei a pilot passage supplying fluid to the receiving hole for unlocking the lock pin is retracted to the retracted hole from the receiving hole,
A communication groove for always communicating the end of the retraction hole where the head of the lock pin advances and retreats and the receiving hole is provided so that the lock pin passes through the pilot passage regardless of the relative phase of the internal rotor and the external rotor. A valve opening / closing timing control device, wherein the valve opening / closing timing control device is held at a retracted position by pressure of supplied oil . The supply of fluid to the pilot passage is performed in a second connection passage that is independent of the first connection passage having a switching valve that controls supply and discharge of fluid to and from the first fluid passage and the second fluid passage. The valve opening / closing timing control device according to claim 1, wherein The pump further includes a pump for supplying fluid to the first fluid passage and the second fluid passage via the switching valve, and the second connection passage is provided between the discharge side of the pump and the switching valve. The valve opening / closing timing control apparatus according to claim 1, wherein the valve opening / closing timing control apparatus is branched from a connection passage and connected to the pilot passage.

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