JP2010223172A - Valve opening-closing timing control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve opening-closing timing control device which can restrain the fact that the control device unintentionally locked when driving an internal combustion engine, by preventing the influence of pulsation pressure of fluid generated by a variation in torque of a camshaft from reaching a third fluid passage for releasing a lock. <P>SOLUTION: A check valve 140 for permitting a flow of the fluid to a first switching valve 100 and prohibiting the flow of the fluid to an oil pump 120, is arranged in the connection passage between the first switching valve 100 for controlling supply-discharge of the fluid to an advanced angle passage 11 and a retarded angle passage 12 and the oil pump 120 for delivering the fluid. A second switching valve 110 for controlling the supply-discharge of the fluid to a pilot passage 13, is connected to the oil pump 120 with the connection passage branched off from between the oil pump 120 and the check valve 140. <P>COPYRIGHT: (C)2011,JPO&INPIT

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.

  Conventionally, as one of valve opening / closing timing control devices, a rotation transmission member that is externally mounted on a rotary shaft for valve opening / closing so as to be relatively rotatable within a predetermined range, a rotational transmission member that transmits rotational power from a crank pulley, and a camshaft are integrated with the camshaft. A fluid pressure chamber formed between the rotation shaft and the rotation transmission member, and divided into an advance angle chamber and a retard angle chamber by the vane; 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 lock formed in the rotation transmission member and biased toward the rotating shaft inside A retraction hole that accommodates the pin, a receiving hole that is formed in the rotating shaft and in which the head of the lock pin is inserted when the relative phase of the rotating shaft and the rotation transmitting member is synchronized at a predetermined phase, and fluid is passed through the receiving hole What is provided with the 3rd fluid passage to supply and discharge is disclosed ( In example, see Patent Document 1.).

  The invention described in Patent Literature 1 includes a first switching valve that controls supply and discharge of fluid to and from the first fluid passage and the second fluid passage, and a second switching valve that controls supply and discharge of fluid to and from the third fluid passage. The fluid supply / discharge to / from the third fluid passage is performed independently of the fluid supply / discharge to / from the first fluid passage and the second fluid passage.

JP-A-10-220207

  However, in such a valve opening / closing timing control device, when the intake valve or the exhaust valve is driven to open / close, the torque fluctuation received by the camshaft from the intake valve or the exhaust valve is transmitted to the vane, and the internal rotor is retarded relative to the external rotor. Also, torque fluctuation is received on the advance side.

  For example, when fluid is supplied to the advance angle chamber and the camshaft phase is changed from the retard side to the advance side target phase with respect to the crankshaft, the internal rotor receives torque fluctuations on the retard side. Since the internal rotor is subjected to torque fluctuation in the direction of decreasing the volume of the advance chamber, the fluid in the advance chamber receives a force flowing out from the advance chamber. Conversely, when the internal rotor receives torque fluctuations toward the advance angle side, the internal rotor receives torque fluctuations in the direction of increasing the volume of the advance angle chamber. appear. This is a fluid pulsation due to torque fluctuation, and is particularly noticeable when the pressure of the fluid supplied from the pump is low. This phenomenon also occurs when a fluid is supplied to the retard chamber and the phase of the camshaft is changed from the advance side to the retard side target phase with respect to the crankshaft.

  The pulsating pressure of the fluid due to the cam torque fluctuation is transferred from the advance angle chamber and / or the retard angle chamber through the first fluid passage and / or the second fluid passage, the first switching valve, the second switching valve, and the third fluid passage. When acting on the lock mechanism, the pressure drop due to the pulsation pressure may act on the unlocking state holding pressure of the lock mechanism, and the lock mechanism may be locked unintentionally.

  In particular, in a so-called intermediate lock type valve opening / closing timing control device in which the relative phase between the rotation shaft and the rotation transmission member is controlled to be locked in the intermediate phase between the most advanced angle phase and the most retarded angle phase, the regulating body of the lock mechanism As the lock pin is accommodated in the retraction hole, the outer periphery of the receiving hole is swung. At this time, if the fluid pressure for holding the lock pin in the accommodation hole pulsates, the lock pin repeatedly projects from the retraction hole or retreats to the retraction hole. As a result, the lock pin may unintentionally enter the receiving hole and become locked.

  The object of the present invention is to prevent the influence of the fluid pulsation pressure generated by the torque fluctuation of the camshaft from reaching the third fluid passage for unlocking, and to prevent the internal combustion engine from entering the locked state unintentionally. The present invention is to provide a valve opening / closing timing control device.

  The first technical means taken in order to solve the above problems includes an internal rotor that rotates integrally with a rotary shaft for opening and closing a valve of an internal combustion engine, a vane attached to the internal rotor, and a predetermined range within the internal rotor. An external rotor which is assembled so as to be relatively rotatable in the interior thereof and which is rotated by power transmitted from a crankshaft of the internal combustion engine, and is formed between the external rotor and the internal rotor, and is advanced by the vane. A fluid pressure chamber that is divided into a retarding chamber, 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, A lock mechanism capable of restraining relative rotation between the internal rotor and the external rotor; and a third mechanism for releasing the restraint by supplying fluid to the lock mechanism and discharging the fluid from the lock mechanism to restrain the fluid. A fluid passage and the first A first switching valve that controls supply and discharge of fluid to and from the body passage and the second fluid passage, a second switching valve that controls supply and discharge of fluid to and from the third fluid passage, the first switching valve, and the And a pump that supplies fluid to the second switching valve, and allows fluid to flow to the first switching valve in a connection passage between the first switching valve and the pump, and allows fluid to flow to the pump. The second switching valve is connected to the pump through a connection passage branched from between the pump and the check valve.

  The second technical means is the first technical means, wherein an opening area of the check valve when fluid is flowing from the pump to the first switching valve is equal to or larger than a pipe hole area of the connection passage. It is to be.

  According to the present invention, the first switching valve for controlling the supply and discharge of the fluid to the first fluid passage for supplying and discharging the fluid to the advance chamber and the second fluid passage for supplying and discharging the fluid to the retard chamber and the fluid A check valve is provided in the connection passage between the pump and the pump that discharges the fluid, allowing the fluid to flow to the first switching valve and prohibiting the fluid from flowing to the pump. And the 2nd switching valve which controls supply and discharge of the fluid to a lock mechanism is connected with the pump by the connection path branched from between the pump and the non-return valve. Therefore, it is possible to prevent the pulsation pressure of the fluid generated by the torque fluctuation of the camshaft from being transmitted from the first switching valve to the pump by the check valve. In addition, since the fluid is supplied to the second switching valve through a connection passage branched from between the pump and the check valve, the second switching valve is not affected by the pulsating pressure of the fluid generated by the camshaft torque fluctuation. A stable fluid can be supplied from the valve to the third fluid passage. As a result, the lock mechanism can hold the unlocked state with a stable fluid pressure and is not locked unintentionally.

  In addition, preferably, the opening area of the check valve when fluid is flowing from the pump to the first switching valve is equal to or larger than the pipe hole area of the connection passage. Normally, if a check valve is provided in the pipe through which the fluid flows, pipe resistance will occur, and the fluid required for relative rotational movement between the internal rotor and the external rotor may not be supplied to the fluid pressure chamber quickly. It is done. However, if the opening area of the check valve when the fluid is flowing is equal to or larger than the pipe hole area of the connection passage, the fluid can be quickly supplied to the fluid pressure chamber even if the check valve is provided.

It is a whole lineblock diagram showing an embodiment of a valve timing control device concerning the present invention. 1 is an overall configuration diagram showing a valve opening / closing timing control mechanism in a locked state of an embodiment of a valve opening / closing timing control device according to the present invention. It is a whole block diagram which shows the valve opening / closing timing control mechanism in the unlocking state of embodiment of the valve opening / closing timing control apparatus which concerns on this invention. It is a whole block diagram which shows the valve timing control mechanism in the most advanced state of embodiment of the valve timing control apparatus which concerns on this invention. It is a whole block diagram which shows the valve opening / closing timing control mechanism in the most retarded state of embodiment of the valve opening / closing timing control apparatus which concerns on this invention.

  Hereinafter, embodiments 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 and 2 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 rotation shaft. The outer rotor 40, the lock plates 60a and 60b, the timing sprocket 70, and the like that are externally rotatably mounted in a range are configured. The outer periphery of the camshaft 10 is rotatably supported by a cylinder head 81. Further, as is well known, the timing sprocket 70 is configured such that rotational power is transmitted in the clockwise direction in FIG. 2 from a crankshaft (not shown) via a timing chain (not shown).

  The camshaft 10 has a well-known cam (not shown) that opens and closes an intake valve (not shown) or an exhaust valve (not shown). As shown in FIGS. There are provided an advance passage 11, a retard passage 12 and a pilot passage 13 extending in the axial direction. The advance passage 11 is formed in a mounting hole for the mounting bolt 16 provided in the camshaft 10, and is formed via an annular passage 91 and a connection passage 92 provided on the outer peripheral side of the supported portion of the camshaft 10. It is connected to the connection port 101 of the 1 switching valve 100. The retard passage 12 is connected to the connection port 102 of the switching valve 100 via an annular passage 93 and a connection passage 94 provided on the outer peripheral side of the supported portion of the camshaft 10. The pilot passage 13 is connected to the connection port 111 of the second switching valve 110 via an annular passage 95 and a connection passage 96 provided on the outer peripheral side of the supported portion of the camshaft 10.

  The first switching valve 100 is controlled in switching operation by a control device (not shown). In the state of switching to the advance position shown in FIGS. 1 and 2 (when not energized), the supply port 103 connected to the oil pump 120 via the check valve 140 is connected to the connection port 101 and communicated. At the same time, the connection port 102 is connected to and communicates with the discharge port 104 connected to the oil pan 130. Further, in the state switched to the retarded position on the right side of the drawing (when energized), the supply port 103 is connected to the connection port 102 and communicates, and the connection port 101 is connected to the discharge port 104 and communicates.

  Therefore, in the advanced position, oil is supplied from the oil pump 120 to the advance passage 11 through the check valve 140 and discharged from the retard passage 12 to the oil pan 130. In the retard position, oil is supplied from the oil pump 120 to the retard passage 12 through the check valve 140 and discharged from the advance passage 11 to the oil pan 130.

  The second switching valve 110 has its switching operation controlled by a control device (not shown). 1, the connection port 111 is connected to and communicates with the supply port 114 connected to the oil pump 120 and the discharge port 113 is connected to the oil pan 130. Communication with is interrupted. Further, in the state switched to the discharge position shown in FIG. 2 (when power is not supplied), the connection port 111 is connected to and communicates with the discharge port 113, and the supply port 114 is closed. Therefore, oil is supplied to the pilot passage 13 in the supply position state, and oil is discharged from the pilot passage 13 to the oil pan 130 in the discharge position state.

  The internal rotor 30 is integrally fixed to the camshaft 10 by bolts 16 and has vane grooves 31 for attaching the four vanes 50 in the radial direction. Further, the internal rotor 30 is in the state shown in FIG. 2, that is, the relative phase of the rotation shaft such as the camshaft 10 and the internal rotor 30 and the rotation transmission member such as the external rotor 40 and the timing sprocket 70 is a predetermined phase ( The receiving groove 32 into which a predetermined amount of the heads of the lock plates 60a and 60b are inserted when synchronized at a suitable intermediate phase between the most advanced angle phase and the most retarded angle phase, and the bottom of the receiving groove 32 and the pilot passage 13 The connecting passage 33 connecting, the connecting passage 34 connecting the advance chamber R1 and the advance passage 11 defined by each vane 50, and the retard chamber R2 and the retard passage 12 defined by each vane 50. And a connection passage 37 to be connected. Each vane 50 is urged radially outward by a spring 51 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 a front plate 41 and a rear plate 42 are integrally fastened by bolts 43 on both sides thereof. Further, the outer rotor 40 is formed with the working chamber R0, which accommodates each vane 50 and is divided into the advance chamber R1 and the retard chamber R2 by the vane 50, and the lock plate 60a. , 60 b and springs 61 a and 61 b for urging them toward the inner rotor 30 are formed in the radial direction of the outer rotor 40.

  The lock plates 60a and 60b are fitted in the retreat grooves 46a and 46b so as to be movable in the radial direction of the external rotor 40, and are urged toward the internal rotor 30 by the springs 61a and 61b. The springs 61a and 61b are compression springs interposed between the lock plates 60a and 60b and the retainers 62a and 62b. The retainers 62a and 62b are assembled and fixed to the external rotor 40.

  The operation of the valve timing control apparatus of the present embodiment configured as described above will be described. When the internal combustion engine is started, the internal combustion engine is in the state shown in FIG. 2, that is, in a state where the heads of the lock plates 60a and 60b are fitted in the receiving grooves 32 and locked at a predetermined phase suitable for starting the internal combustion engine. Is started. When the internal combustion engine is started, the oil pump 120 is driven to start supplying oil. The oil discharged from the oil pump 120 advances from the supply port 103 of the first switching valve 100 via the check valve 140 via the connection port 101, the connection passage 92, the annular passage 91, the advance passage 11, and the connection passage 34. It is supplied to the corner chamber R1. On the other hand, the oil supplied from the oil pump 120 to the second switching valve 110 is not supplied to the pilot passage 13 because the supply port 114 of the second switching valve 110 is closed, and the locked state is maintained. .

  When the second switching valve 110 is energized by a signal from a control device (not shown) after the internal combustion engine is started, the oil discharged from the oil pump 120 is supplied to the second switching valve 110 as shown in FIG. 114 is supplied to the receiving groove 32 through the connection port 111, the connection passage 96, the annular passage 95, the pilot passage 13, and the connection passage 33. When oil is supplied to the receiving groove 32, as shown in FIG. 3, the lock plates 60a and 60b are pushed radially outward against the spring 61, and are released from the receiving groove 32 to the retraction grooves 46a and 46b. evacuate. Thus, the locked state by the lock plates 60a and 60b is released, and the rotation shaft side members such as the camshaft 10, the inner rotor 30 and the vane 50 can be rotated relative to the rotation transmitting member such as the outer rotor 40.

  Further, oil is supplied from the oil pump 120 to the advance chamber R1 through the first switching valve 100, the advance passage 11 and the like in a state where the lock by the lock plates 60a and 60b shown in FIG. 3 is released. Then, oil is discharged from the retardation chamber R2 to the oil pan 130 through the retardation passage 12, the switching valve 100, and the like. Then, the rotating shaft side members such as the camshaft 10, the inner rotor 30 and the vane 50 rotate relative to the rotation transmitting member such as the outer rotor 40 in the clockwise direction of FIG. 3, that is, the state shown in FIG. It becomes the state of the most advance angle at which the volume of the chamber R2 is minimized.

  In addition, when the first switching valve 100 is energized by a signal from a control device (not shown) in the state of the most advanced angle shown in FIG. 4, the oil discharged from the oil pump 120 as shown in FIG. Is supplied from the supply port 103 of the first switching valve 100 via the check valve 140 to the retardation chamber R2 via the connection port 102, the connection passage 94, the annular passage 93, the retardation passage 12, and the connection passage 37. The On the other hand, oil is discharged from the advance chamber R1 to the oil pan 130 through the advance passage 11 and the switching valve 100 and the like. Then, the rotating shaft side members such as the camshaft 10, the inner rotor 30 and the vane 50 rotate relative to the rotation transmitting member such as the outer rotor 40 in the counterclockwise direction of FIG. It becomes the most retarded state in which the volume of the corner chamber R1 is minimized.

  When the internal combustion engine is driven, the valve opening / closing timing is controlled to an optimum phase by reciprocating between the most advanced angle state and the most retarded angle state in accordance with the operating state of the internal combustion engine. At that time, when shifting from the most advanced state shown in FIG. 4 to the most retarded state shown in FIG. 5, the state in which the lock plate 60a is accommodated in the retracting groove 46a is maintained. When shifting from the most retarded angle state shown in FIG. 5 to the most advanced angle state shown in FIG. 4, it is necessary to maintain the state in which the lock plate 60b is accommodated in the retreat groove 46b.

  In the present embodiment, the first switching valve 100 is connected to the connection passage between the first switching valve 100 that controls the supply and discharge of oil to the advance passage 11 and the retard passage 12 and the oil pump 120 that discharges oil. A check valve 140 is provided to permit the oil flow and prohibit the oil flow to the oil pump 120. The second switching valve 110 that controls the supply and discharge of oil to and from the pilot passage 13 is connected to the oil pump 120 through a connection passage that branches from between the oil pump 120 and the check valve 140. Therefore, oil pulsation pressure generated by torque fluctuation of the camshaft 10 can be prevented from being transmitted from the first switching valve 100 to the oil pump 120 by the check valve 140. In addition, since the second switching valve 110 is supplied with oil through a passage branched from the connection passage between the oil pump 120 and the check valve 140, the oil pulsation pressure generated by the torque fluctuation of the camshaft 10 has an influence. Without this, stable oil can be supplied from the second switching valve 110 to the pilot passage 13. As a result, stable oil is supplied to the receiving groove 32, so that the state in which the lock plates 60a and 60b are accommodated in the retreat grooves 46a and 46b can be maintained, and it is possible to prevent unintentional locking.

  In the description of the present embodiment, the case where the predetermined phase is an intermediate phase between the most advanced angle phase and the most retarded angle phase suitable for starting the internal combustion engine has been described. However, the present invention is not limited to this. Needless to say, the predetermined phase may be the most retarded phase or the most advanced phase.

10 ... Camshaft 11 ... Advance passage (first fluid passage)
12 ... retarded passage (second fluid passage)
13: Pilot passage (third fluid passage)
30 ... Inner rotor 32 ... receiving groove (receiving part, lock mechanism))
40 ... External rotor 41 ... Front plate 42 ... Rear plates 46a, 46b ... Retraction groove (retraction portion)
50 ... Vane 60a, 60b ... Lock plate (regulator, lock mechanism)
81 ... Cylinder head 100 ... First switching valve 110 ... Second switching valve 120 ... Oil pump (pump)
130 ... Oil pan 140 ... Check valve R0 ... Working chamber (fluid pressure chamber)
R1 ... Advance angle chamber R2 ... Delay angle chamber

Claims (2)

An internal rotor that rotates integrally with a rotary shaft for opening and closing a valve of an internal combustion engine;
A vane attached to the inner rotor;
An external rotor that is assembled to the internal rotor so as to be relatively rotatable within a predetermined range, and is rotated by power transmitted from a crankshaft of the internal combustion engine;
A fluid pressure chamber formed between the outer rotor and the inner rotor and divided into an advance chamber and a retard chamber by the vane;
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 mechanism capable of restraining relative rotation between the inner rotor and the outer rotor;
A third fluid passage for supplying fluid to the lock mechanism to release the restraint, and discharging and restraining the fluid from the lock mechanism;
A first switching valve that controls supply and discharge of fluid to and from the first fluid passage and the second fluid passage;
A second switching valve for controlling supply and discharge of fluid to and from the third fluid passage;
A pump for supplying fluid to the first switching valve and the second switching valve,
A check valve is provided in a connection passage between the first switching valve and the pump, and permits the flow of fluid to the first switching valve and prohibits the flow of fluid to the pump;
The valve switching timing control device according to claim 1, wherein the second switching valve is connected to the pump through a connection passage branched from the pump and the check valve.   2. The valve opening / closing timing control device according to claim 1, wherein an opening area of the check valve when a fluid flows from the pump to the first switching valve is equal to or larger than a pipe hole area of the connection passage.

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