JP4601591B2 - Valve operating apparatus for an internal combustion engine having a valve deactivation mechanism - Google Patents

Description

  The present invention relates to a valve operating system including a valve deactivation mechanism for deactivating an engine valve, which is an intake valve or an exhaust valve, in accordance with an operation state of the internal combustion engine.

A valve operating apparatus for an internal combustion engine includes a cam follower driven by a valve operating cam provided on a camshaft, and a valve pausing mechanism provided on the cam follower for pausing the engine valve, and the valve pausing mechanism transmits to the cam follower. An operating element that moves between a valve operating position that transmits the valve driving force of the valve drive cam that has been transmitted to the engine valve and a valve resting position that does not transmit the valve driving force transmitted to the cam follower to the engine valve, and hydraulic pressure of the hydraulic oil And a resilient means for causing a resilient force to act on the actuating element against the hydraulic driving force acting on the actuating element based on the above (see, for example, Patent Document 1).
JP 2003-27908 A

  The hydraulic pressure of the hydraulic oil that acts on the operating element is a low hydraulic pressure that causes the hydraulic element to apply a hydraulic driving force that is equal to or less than the elastic force preset by the elastic means (hereinafter referred to as “set elastic force”) ( (Hereinafter referred to as “low hydraulic pressure state”), the operating element occupies the valve resting position, and the hydraulic pressure of the operating oil causes a high hydraulic pressure (hereinafter referred to as “high hydraulic pressure”) to act on the operating element to overcome the set elastic force. In a valve deactivation mechanism in which the operating element occupies the valve operating position when it is in the “hydraulic state”), the operating element reliably occupies the valve operating position immediately after the start of the operation of the internal combustion engine, such as when starting the internal combustion engine. May be difficult. For example, when hydraulic oil is supplied from an oil pump driven by the power of the internal combustion engine, the engine speed is extremely low at the time of starting the internal combustion engine or the like (hereinafter referred to as “very low speed operation”). Then, it takes a relatively long time for the hydraulic oil to reach a high hydraulic pressure state, and during that time, the engine valve becomes inactive and engine output may be insufficient. This also applies to a variable cylinder internal combustion engine in which some cylinders are deactivated by a valve deactivation mechanism in a multi-cylinder internal combustion engine. When the vehicle starts to start immediately after starting, torque fluctuation increases and engine stall is likely to occur.

  The present invention has been made in view of such circumstances, and the invention according to claims 1 to 4 is directed to a valve operating device for an internal combustion engine having a valve deactivation mechanism. It is an object of the present invention to ensure that the engine valve is in an operating state even in a low hydraulic pressure state so that a large engine output can be obtained even at an extremely low speed operation of the internal combustion engine. The invention according to claim 2 further improves the movement responsiveness of the actuating element by the hydraulic driving force over a long period of time by improving the wear resistance at the working oil side working part on which the working oil acts. The invention according to claim 3 further aims to reduce the weight of the actuating element, and the invention according to claim 4 further provides the startability of the internal combustion engine provided with the cylinder capable of resting. The purpose is to promote warm-up as well as to improve.

According to the first aspect of the present invention, a cam follower (23) driven by a valve-operating cam (21a, 22a) provided on a cam shaft (21, 22) and an engine valve provided in the cam follower (23) in a dormant state. A valve operating mechanism (20) of an internal combustion engine (E) comprising a valve pausing mechanism (30) for making the valve pausing mechanism (30) comprising the cam follower (23) and the engine valve (8, 9) , The valve operating position for transmitting the valve driving force of the valve cam (21a, 22a) transmitted to the cam follower (23) to the engine valve (8, 9), the cam follower 23 and the engine valve. The actuating element (32) which moves between the valve resting position where the valve driving force transmitted to the cam follower (23) is not transmitted to the engine valve (8, 9) by releasing the linkage with (8, 9). ) And hydraulic driving force acting on the operating element (32) based on the hydraulic pressure of the hydraulic oil In the valve operating device (20) of the internal combustion engine (E) provided with a resilient means (33) that causes the resilient element (32) to act on the actuating element (32), the actuating element (32) Occupying the valve operating position by force, occupying the valve resting position by the hydraulic driving force, and the hydraulic driving force is a driving force by hydraulic oil discharged from an oil pump (55) driven by a crankshaft. The valve pause mechanism (30) includes a holder (31) that slidably supports the operating element (32), and the operating element (32) has a hydraulic oil acting portion on which the hydraulic driving force acts. (32a), a transmission part (32d) for transmitting the valve driving force transmitted through the cam follower (23) to the engine valve (8, 9), and the valve to the engine valve (8, 9). Space portions (42, 43) that do not transmit a driving force, and a resilient side acting portion on which the resilient force acts (32b), and the actuating element (32) interlocks the cam follower (23) and the engine valve (8, 9) via the transmission portion (32d) in the valve actuated position, In the valve resting position, the space portion (42, 43) releases the interlock between the cam follower (23) and the engine valve (8, 9), and the hydraulic oil side action portion (32a) and the transmission portion (32d). Is arranged to face the space (42, 43) with the space (42, 43) sandwiched in the moving direction of the actuating element (32), and the ballistic action part (32b) is arranged in the direction of movement of the space (42 , 43) on the opposite side of the transmission part (32d) on the side opposite to the transmission part (32d) and accommodating the elastic member (33) is formed, and the actuating element (32) is provided in the moving direction. A communication path (46) for communicating the space (42, 43) and the storage chamber (45) is provided at a position overlapping the transmission part (32d). Is, and, in Rukoto are notches formed in the cam shaft (21, 22) inboard end (32 b) of the space portion provided in the actuating element (32) (43), said actuating element (32) Further, the valve can be moved to the valve rest position even at an idling rotation speed including a cranking rotation speed when the engine is started .
According to a second aspect of the present invention, the internal combustion engine (E) according to the first aspect comprises a plurality of cylinders that can be switched between an operation state and a deactivation state according to the engine temperature, and an operation cylinder that is always in an operation state. The cylinder (1a) is a multi-cylinder internal combustion engine (E), and all the intake valves (8) and exhaust valves (9) of the restable cylinder are put into a pause state by the valve pause mechanism (30). is composed of the engine valve (8,9), the hydraulic pressure of the hydraulic fluid is controlled in accordance with the engine temperature by the oil pressure control valve provided in the hydraulic control system (57) (56), the hydraulic control valve (56 ) So that the operating element (32) occupies the valve operating position when the engine temperature is equal to or lower than a predetermined temperature in the warm-up state of the internal combustion engine (E), and the engine temperature exceeds the predetermined temperature. When the operating element exceeds The hydraulic pressure of the hydraulic oil is controlled so that the child (32) can occupy the valve rest position.

According to the first aspect of the present invention, in the valve pausing mechanism, the operation occupies the valve operating position and the valve pausing position by moving according to the hydraulic driving force of the hydraulic oil and the resilient force of the resilient means that oppose each other. Since the element occupies the valve operating position by the elastic force, the valve operating position is surely ensured by the elastic force even when the hydraulic oil acting on the operating element is in a low hydraulic pressure state, for example, at the start of the internal combustion engine. Since the valve driving force of the valve cam transmitted to the cam follower is transmitted to the engine valve, a large engine output can be obtained even at extremely low speed operation such as when the internal combustion engine is started.
According to the first aspect of the present invention, the transmission portion where the reaction force from the engine valve acts on the operating element is a technique in which the transmission portion is adjacent to the hydraulic oil side operating portion without sandwiching the space portion in the moving direction of the operating element Compared with the holder, since the space portion is interposed in the moving direction, the reaction force acting on the hydraulic oil side action portion is reduced because the space portion is separated from the hydraulic oil side action portion. Thus, the wear between the operating element that slides and the holder is reduced, and the gap between the holder and the hydraulic oil side action portion is prevented from being enlarged. As a result, since the leakage of hydraulic oil through the gap is reduced, the movement responsiveness of the operating element by the hydraulic driving force is well maintained over a long period of time.
According to claim 1, wherein the matter, the communication passage for communicating the accommodating chamber space, as compared to the technique with resilient side operating portion in the moving direction and the transmitting portion is not adjacent to one another, overlaps the transmitting portion Since the passage can be made longer in the moving direction, the operating element is reduced in weight, so that the movement responsiveness by the hydraulic driving force and the elastic force is improved, and there is a valve pausing mechanism that can move together with the engine valve. Since the weight is reduced and the inertial mass of the member that moves together with the engine valve is reduced, the opening / closing response of the engine valve during high-speed operation is improved.
According to claim 2, wherein the matter, the engine temperature is, the internal combustion engine is at the predetermined temperature or less when in a warmed-up state, the internal combustion engine is operated by the all-cylinder operation in which all cylinders are running, start In addition, the warm-up of the internal combustion engine is promoted. When the engine temperature exceeds the predetermined temperature, the internal combustion engine is operated by partial cylinder operation in which the cylinder capable of being deactivated is deactivated, so that fuel efficiency is improved.

Embodiments of the present invention will be described below with reference to FIGS.
Referring to FIG. 1, a valve operating apparatus 20 to which the present invention is applied is a multi-cylinder four-stroke internal combustion engine E mounted on a motorcycle as a vehicle in a horizontal arrangement in which a crankshaft extends in the vehicle width direction. Prepared for. The internal combustion engine E is composed of a plurality of cylinders, each of which is a cylinder that can be deactivated depending on the engine operation state, and a remaining cylinder that is an operation cylinder that is always in an operation state. This is a variable-cylinder internal combustion engine that can be changed according to the engine operating state.

The internal combustion engine E includes a plurality of cylinders 1a arranged in series, here, a cylinder block 1 integrally formed with four cylinders 1a, a cylinder head 2 coupled to the upper end of the cylinder block 1, and a cylinder head 2 An engine body including a head cover 3 coupled to the upper end portion and a crankcase (not shown) coupled to the lower end portion of the cylinder block 1 is provided.
In this embodiment, unless otherwise specified, the vertical direction is a direction parallel to the cylinder axis Lc, and the direction in which the cylinder head 2 is coupled to the cylinder block 1 is the upward direction.

A piston 4 connected to the crankshaft via a connecting rod is fitted to each cylinder 1a so as to be able to reciprocate. The cylinder head 2 is provided with a combustion chamber 5 formed by a recess facing the piston 4 in the cylinder axial direction for each cylinder 1a, and an intake air having a pair of intake ports 6a that open to the combustion chambers 5 respectively. An exhaust port 7 having a port 6 and a pair of exhaust ports 7a and an ignition plug (not shown) facing the combustion chamber 5 are provided.
The cylinder head 2 is provided with an intake valve 8 and an exhaust valve 9 as engine valves each composed of a poppet valve that is always urged in the valve closing direction by a valve spring 10. A pair of intake valves 8 and a pair of exhaust valves 9 provided for each cylinder 1a (or for each combustion chamber 5) are driven by a valve operating device 20, and a pair of intake ports 6a and a pair of exhaust ports, respectively. 7a is opened and closed. The intake valve 8 and the exhaust valve 9 are each opened and closed in the direction of the axis Av by slidably fitting the valve stems 8a and 9a to the cylindrical valve guide 11 fixed to the cylinder head 2. It can reciprocate in the direction.

The internal combustion engine E includes an intake pipe (not shown) that includes an intake pipe that is connected to the intake-side connecting portion 2i of the cylinder head 2 and guides the intake air to the combustion chamber 5, and an intake air that is attached to the intake pipe. And a fuel injection valve (not shown) for supplying fuel to the engine and an exhaust device (not shown) for guiding the exhaust gas flowing out from the combustion chamber 5 to the outside of the internal combustion engine E.
The intake air measured by the throttle valve provided in the intake device is mixed with the fuel injected from the fuel injection valve to form an air-fuel mixture, which is taken in when the intake valve 8 is opened in the intake stroke. It is sucked into the combustion chamber 5 through the port 6 and compressed in the compression stroke. The air-fuel mixture is ignited and burned by the spark plug at the end of the compression stroke, and the piston 4 driven by the pressure of the combustion gas in the expansion stroke rotates the crankshaft. When the exhaust valve 9 is opened in the exhaust stroke, the combustion gas flows out from the combustion chamber 5 to the exhaust port 7 as exhaust gas, and is attached to the exhaust-side connecting portion 2e of the cylinder head 2 where the outlet of the exhaust port 7 opens. It is discharged to the outside through the exhaust device provided with an exhaust pipe.

A DOHC type valve gear 20 provided in the cylinder head 2 and disposed in a valve valve chamber 12 formed by the cylinder head 2 and the head cover 3 has the intake valve 8 and the exhaust valve 9 at the rotational position of the crankshaft. Accordingly, it opens and closes at a predetermined timing. The valve gear 20 is provided integrally with the intake camshaft 21 and the intake camshaft 21, which are a pair of camshafts that are rotatably supported by the cylinder head 2 and have rotation center lines parallel to each other. The intake cam 21a that is a valve operating cam that opens and closes the intake valve 8 and the exhaust cam 22a that is integrally provided on the exhaust cam shaft 22 and opens and closes the exhaust valve 9 are in sliding contact with the intake cam 21a. In addition, a valve lifter 23 as a cam follower driven by the valve driving force of the intake cam 21a, a valve lifter 23 as a cam follower which is in sliding contact with the exhaust cam 22a and driven by the valve driving force of the exhaust cam 22a, the intake valve 8 and the exhaust valve And a valve pausing mechanism 30 that puts 9 into the pausing state.
The valve deactivation mechanism 30 includes all the intake valves 8 and exhaust valves 9 of the cylinder capable of deactivation (corresponding to the cylinder 1a shown in FIG. 1) and one of the pair of intake valves 8 of the working cylinder. One intake valve 8 and one exhaust valve 9 of a pair of exhaust valves 9 are provided.
The intake camshaft 21 and the exhaust camshaft 22 are rotationally driven at a half rotational speed by the power of the crankshaft transmitted through a transmission mechanism having a timing chain. Each valve lifter 23, which is a cylindrical member provided with a ceiling wall 23 a at the upper end and opened at the lower end, is fitted in a columnar fitting hole provided in the support portion 13 of the cylinder head 2 and is parallel to the axial direction Av. It is slidably supported.

  Hereinafter, the valve pause mechanism 30 will be mainly described. Since the valve deactivation mechanism 30 has the same structure for the intake valve and the exhaust valve, the valve deactivation mechanism 30 for the intake valve will be mainly described in the following description. Unless otherwise specified, the members related to the operation of the intake valve 8 such as the intake valve 8, the intake cam shaft 21, the intake cam 21a, and the valve lifter 23 are as follows. Each corresponds to the exhaust valve 9 and members related to the operation of the exhaust valve 9 such as the exhaust cam shaft 22, the exhaust cam 22a, and the valve lifter 23.

  Between the valve lifter 23 and the intake valve 8, the intake cam of the valve drive force of the intake cam 21 a transmitted to the valve lifter 23 is linked to the valve lifter 23, which is pressed by the intake cam 21 a and reciprocates. A valve pause mechanism 30 that switches between transmission and non-transmission to the valve 8 is provided inside the valve lifter 23. Each valve deactivation mechanism 30 is controlled by hydraulic oil of a hydraulic control system, which will be described later, and during specific operation of the internal combustion engine E, during operation where the engine temperature exceeds a predetermined temperature described later, and during low speed operation or low load operation For example, the intake valve 8 is put into a rest state regardless of the reciprocating motion of the valve lifter 23 driven by the intake cam 21a.

  2 and 3 together, the valve pausing mechanism 30 is slidably fitted into the holder 31 and a cylindrical holder 31 slidably fitted inside the valve lifter 23. A cylindrical slide pin 32 as an operating element supported as a support, and a bullet that is arranged between the holder 31 and the slide pin 32 and that opposes the hydraulic drive force acting on the slide pin 32 based on the hydraulic pressure of the hydraulic oil. A control spring 33 as a resilient means for applying a force to the slide pin 32, and a slide pin 32 provided on the holder 31 to prevent the slide pin 32 from rotating about its axis and to be in the axis direction Ap of the slide pin 32. And a stopper pin 34 for restricting movement in the moving direction (hereinafter referred to as “moving direction”).

The holder 31 includes a ring portion 31a having an outer peripheral surface that is in surface contact with the inner peripheral surface of the valve lifter 23, a connecting portion 31b that connects the ring portion 31a in the diametrical direction, and projects upward from the central portion of the connecting portion 31b. And a pressing portion 31c that contacts the ceiling wall 23a and presses the ceiling wall 23a. An inner annular oil passage 51 formed of an annular groove over the entire circumference is provided on the outer peripheral surface of the ring portion 31a. The connecting portion 31b has a cylindrical accommodation hole 40 as an accommodation portion having an open end 40a having an axis perpendicular to the axis of the valve lifter 23 and opening to the oil passage 51 and a closed end 40b closed by the bottom wall 35. In addition, a front end 8a1 of the valve stem 8a of the intake valve 8 (in the exhaust valve 9, the front end 9a1 of the valve stem 9a) penetrates in the axial direction Av and a through hole 41 that opens to the accommodation hole 40 is provided. . The slide pin 32 is accommodated in the accommodation hole 40 so as to be capable of reciprocating in the movement direction. The pressing portion 31c is formed with a hole 42 into which the distal end portion 8a1 can be inserted and whose lower end opens into the accommodation hole 40.
The support spring 36 disposed so as to surround the valve spring 10 brings the pressing portion 31c into contact with the ceiling wall 23a and biases the valve lifter 23 through the holder 31 so that the ceiling wall 23a contacts the intake cam 21a. .

  The holder 31 has a hydraulic chamber 44 opened to the oil passage 51 by the connecting portion 31b and one end portion 32a of the slide pin 32 on the open end 40a side, and the connecting portion 31b on the closed end 40b side. Due to the other concave end portion 32b of the slide pin 32 and the bottom wall 35, a control spring 33 for urging the slide pin 32 in a direction to reduce the volume of the hydraulic chamber 44 is provided at both ends of the end portion 32b and the bottom wall 35. A storage chamber 45 is formed that is stored in contact with each other. Further, an outer annular oil passage 53 formed by an annular groove is provided on the inner peripheral surface of the support portion 13 over the entire circumference, and through an oil passage 52 including a through hole provided in the side wall of the valve lifter 23. The oil passage 53 is always in communication with the oil passage 51.

  An insertion hole 43 is provided in the middle portion of the slide pin 32 in the axial direction Ap as a space portion through which the distal end portion 8a1 can be inserted and penetrated and can be connected to the through hole 41 and the hole 42 substantially coaxially. It is done. The insertion hole 43 is formed on the outer peripheral surface of the slide pin 32 and can be opposed to the through hole 41 in the axial direction Av on the through hole 41 side. It opens adjacently in the direction Ap. The contact surface 32d is provided between the insertion hole 43 and the end portion 32b in the axial direction Ap.

  The end portion 32a and the contact surface 32d are arranged to face each other across the insertion hole 43 in the moving direction of the slide pin 32 (that is, the axial direction Ap). The end portion 32b is adjacent to the contact surface 32d on the side opposite to the insertion hole 43 in the moving direction. The slide pin 32 is provided with a communication hole 46 as a communication path that connects the insertion hole 43 and the storage chamber 45 at a position overlapping the contact surface 32d in the movement direction. Further, the end portion 32b has a valve lifter 23 opened to the valve train chamber 12 through a hole 48 serving as a communication path provided in the connecting portion 31b at a portion facing the bottom wall 35 in the moving direction. A notch 47 is provided as a communication path communicating with the inner space. The accommodation chamber caused by the volume increase / decrease of the accommodation chamber 45 due to the movement of the slide pin 32 due to the flow of air and mist-like lubricating oil mixed in the air through the communication hole 46, the notch 47 and the hole 48 The increase / decrease in the pressure of 45 is eliminated, the movement of the slide pin 32 becomes smooth, and the control spring 33, the end portion 32b, the bottom wall 35 and the contact portion are lubricated by the lubricating oil.

The slide pin 32 has a hydraulic drive force based on the hydraulic pressure of the hydraulic oil in the hydraulic chamber 44 acting on the end portion 32a as the hydraulic oil side action portion, and a control spring that comes into contact with the end portion 32b as the elastic side action portion. The elastic force generated by 33 acts in opposite directions in the axial direction Ap. Then, the slide pin 32 causes the valve drive force of the intake cam 21a transmitted to the valve lifter 23 by interlocking the valve lifter 23 and the intake valve 8 to the intake valve 8 in accordance with the hydraulic drive force and the resilient force that oppose each other. It moves in the axial direction Ap between the valve operating position to be transmitted and the valve rest position where the valve driving force transmitted to the valve lifter 23 is not transmitted to the intake valve 8 by releasing the interlock between the valve lifter 23 and the intake valve 8. .
A stopper pin 34 that is press-fitted into a pair of mounting holes 49 provided in the holder 31 on the open end 40a side of the accommodation hole 40 and passes through a slit 32e provided open in the hydraulic chamber 44 is shown in FIG. ), The stopper 32 that defines the valve operating position of the slide pin 32 is configured by contacting the end 32a urged by the elastic force within the slit 32e. On the other hand, as shown in FIG. 2B, the bottom wall 35 abuts the end portion 32b of the slide pin 32 biased by the hydraulic driving force, thereby defining the valve rest position of the slide pin 32.

  More specifically, referring to FIG. 2A, the hydraulic pressure of the hydraulic oil in the hydraulic chamber 44 is the elasticity of the control spring 33 when the slide pin 32 and the stopper pin 34 are in contact with each other. When in a low hydraulic pressure state in which a hydraulic driving force equal to or less than the set elastic force is applied to the slide pin 32, the slide pin 32 is urged by the control spring 33 and occupies the valve operating position by the elastic force. At this time, the insertion hole 43 is displaced in the axial direction Ap from the through hole 41 and the hole 42, and the contact surface 32d is positioned so as to overlap the through hole 41 and the hole 42 in the axial direction Ap (or moving direction). The front end 8a1 of the intake valve 8 penetrating through the hole 41 is in a position where it can contact the contact surface 32d, and the front end 8a1 is not inserted into the insertion hole 43. The slide pin 32 transmits the valve driving force of the intake cam 21a transmitted via the valve lifter 23 to the intake valve 8 on the contact surface 32d as a transmission portion. As a result, the valve driving force of the intake cam 21a is transmitted to the intake valve 8 via the valve lifter 23, the holder 31 and the slide pin 32, and the intake valve 8 enters an operating state in which it opens and closes according to the rotation of the intake cam 21a. Become.

  On the other hand, referring to FIG. 2B, when the hydraulic oil pressure in the hydraulic chamber 44 is in a high hydraulic pressure state in which the hydraulic drive force exceeding the set elastic force is applied to the slide pin 32, the slide pin 32 and The slide pin 32 occupies the valve rest position by contacting the bottom wall 35. At this time, the insertion hole 43 is aligned substantially coaxially with the through-hole 41 and the hole 42 in the axial direction Av, and the insertion hole 43 is positioned so as to overlap the through-hole 41 and the hole in the axial direction Ap. The distal end portion 8 a 1 penetrating through the through hole 41 does not come into contact, and the distal end portion 8 a 1 can be inserted into the insertion hole 43. Therefore, the insertion hole 43 is a portion of the slide pin 32 that does not transmit the valve driving force of the intake cam 21 a transmitted through the valve lifter 23 to the intake valve 8. For this reason, even if the valve lifter 23, the holder 31 and the slide pin 32 are moved in the axial direction Av by the valve driving force of the intake cam 21a, the tip 8a1 only moves forward and backward in the insertion hole 43 and the hole 42. The valve driving force is not transmitted to the intake valve 8, and the intake valve 8 enters a resting state in which the closed valve state is maintained regardless of the rotation of the intake cam 21a.

  Referring to FIGS. 1 and 2, the hydraulic control system for moving the slide pin 32 of the valve deactivation mechanism 30 includes an oil pump 55 driven by the power of the crankshaft as a hydraulic source and discharges from the oil pump 55. The lubricated oil is used as hydraulic oil. Further, the hydraulic control system controls the hydraulic pressure of the hydraulic oil in the hydraulic chamber 44 by controlling the hydraulic pressure of the hydraulic fluid provided from the oil pump 55 and the hydraulic fluid 54 provided in the cylinder head 2 and communicating with the hydraulic fluid 53. A control valve 57 that controls the operation of the hydraulic control valve 56 in accordance with the engine temperature (for example, cooling water temperature) in the engine operating state and the engine rotational speed or the engine load. Prepare. The hydraulic control valve 56 is a control device 57 to which detection signals from operating state detection means such as a temperature sensor that detects engine temperature, a rotation speed detection sensor that detects engine rotation speed, or a load sensor that detects engine load are input. From the oil passage 54 so that the hydraulic pressure in the hydraulic chamber 44 is in a high hydraulic pressure state during the specific operation of the internal combustion engine E, and the hydraulic pressure in the hydraulic chamber 44 is in a low hydraulic pressure state during other operations. Controls hydraulic oil pressure.

Since the discharge pressure of the oil pump 55 can change according to the engine speed, the hydraulic pressure of the hydraulic oil can change according to the engine speed. For this reason, when the internal combustion engine E is started, the hydraulic pressure of the hydraulic oil may not reach a high hydraulic pressure during an extremely low speed operation at an extremely low engine speed. However, the slide pin 32 is urged by the control spring 33 to operate the valve when the hydraulic oil pressure in the hydraulic chamber 44 is in a low hydraulic pressure state, such as during extremely low speed operation, and during operations other than the specific operation. Securely occupies position.
Here, the extremely low speed operation is a time when the internal combustion engine E is operated at an engine rotation speed that includes the cranking rotation speed and less than the idle rotation speed, and is not included in the low speed operation as the specific operation.

  Then, the internal combustion engine E uses, for example, the following operation modes according to whether the intake valve 8 and the exhaust valve 9 are in the activated state or the deactivated state by each valve deactivation mechanism 30, that is, all Operation mode in full cylinder operation in which the cylinder 1a is operated, operation mode in partial cylinder operation in which the cylinder that can be deactivated is deactivated, and one intake valve 8 and one exhaust valve 9 of the operation cylinder are deactivated during partial cylinder operation. It becomes possible to operate in the following operation mode.

  In addition, the hydraulic control valve 56 controls the hydraulic pressure of the hydraulic oil as follows in order to control the valve deactivation mechanism 30 provided for all the intake valves 8 and the exhaust valves 9 of the deactivatable cylinder according to the engine temperature. To do. That is, when the engine temperature is equal to or lower than a predetermined temperature when the internal combustion engine E is in a warm-up state, the hydraulic control valve 56 occupies a low hydraulic pressure position at which the hydraulic pressure in the hydraulic chamber 44 is lowered, and the slide pin 32 is The valve operating position is occupied by the elastic force of the control spring 33 which is larger than the hydraulic driving force. For this reason, when the engine temperature is equal to or lower than the predetermined temperature, the internal combustion engine E is operated by an all cylinder operation in which all the cylinders 1a are operated. On the other hand, when the engine temperature exceeds the predetermined temperature, the hydraulic control valve 56 is a high hydraulic pressure position where the hydraulic pressure in the hydraulic chamber 44 can be changed to a high hydraulic pressure state according to the hydraulic pressure of the hydraulic oil supplied from the oil pump 55. Occupy. When the hydraulic pressure of the hydraulic oil from the oil pump 55 is sufficiently high, the slide pin 32 occupies the valve rest position by a hydraulic driving force that overcomes the elastic force of the control spring 33. For this reason, when the engine temperature exceeds the predetermined temperature, the internal combustion engine E is operated by the partial cylinder operation in which the incapable cylinder is deactivated.

Next, operations and effects of the embodiment configured as described above will be described.
The slide pin 32 of the valve pausing mechanism 30 provided in the valve gear 20 of the internal combustion engine E occupies the valve operating position by the elastic force of the control spring 33, and occupies the valve pausing position by the hydraulic drive force of the hydraulic oil. In the valve resting mechanism 30, the slide pin 32 that moves according to the hydraulic driving force and the resilient force that oppose each other and occupies the valve operating position and the valve resting position occupies the valve operating position by the resilient force. Even when the hydraulic oil pressure acting on the slide pin 32 during a very low speed operation such as when the engine E is started is in a low hydraulic pressure state, the valve operating position is reliably occupied by the elastic force and transmitted to the valve lifter 23. Since the valve driving force of the intake cam 21a is transmitted to the intake valve 8, a large engine output can be obtained even during extremely low speed operation. For this reason, the startability of the internal combustion engine E and the startability of the motorcycle are improved.

  The valve pause mechanism 30 includes a holder 31 that slidably supports a slide pin 32. The slide pin 32 is transmitted via an end portion 32a as a hydraulic oil side acting portion on which a hydraulic driving force acts and a valve lifter 23. The contact surface 32d for transmitting the valve driving force of the intake cam 21a to the intake valve 8, the insertion hole 43 for not transmitting the valve driving force to the intake valve 8, and the elastic side acting portion where the elastic force acts. An end portion 32b is provided, and the slide pin 32 interlocks the valve lifter 23 and the intake valve 8 via the contact surface 32d in the valve operating position, and the valve lifter 23 and the intake valve 8 are connected by the insertion hole 43 in the valve rest position. The end portion 32a and the abutting surface 32d are arranged to face each other with the insertion hole 43 in the moving direction (axial direction Ap) of the slide pin 32, so that the intake valve at the slide pin 32 is released. The contact surface 32d on which the reaction force from 8 acts is the contact surface Compared to the technique adjacent to the hydraulic oil side working part without sandwiching the insertion hole in the moving direction of the slide pin, since the insertion hole 43 is interposed in the moving direction, it is separated from the end part 32a. Since the component force of the reaction force acting on 32a is reduced, the wear between the slide pin 32 sliding on the holder 31 and the holder 31 is reduced, and the gap between the holder 31 and the end 32a is enlarged. Is suppressed. As a result, the leakage of hydraulic oil from the hydraulic chamber 44 through the gap is reduced, so that the movement responsiveness of the slide pin 32 by the hydraulic driving force is well maintained over a long period of time.

  The end portion 32b forms an accommodation chamber 45 that is adjacent to the contact surface 32d on the opposite side of the insertion hole 43 in the movement direction and accommodates the control spring 33, and the slide pin 32 has a contact surface 32d in the movement direction. Is provided in the position where the insertion hole 43 and the accommodation chamber 45 are communicated with each other, the communication hole 46 is a technology in which the elastic side action portion and the contact surface are not adjacent to each other in the moving direction. Compared with the contact surface 32d, since the hole can be made long in the moving direction, the slide pin 32 is reduced in weight, so that the movement responsiveness by the hydraulic driving force and the elastic force is improved. Since the valve pause mechanism 30 that can move together with the intake valve 8 is reduced in weight and the inertial mass of the member that moves with the intake valve 8 is reduced, the open / close response of the intake valve 8 during high speed operation is improved.

  In the internal combustion engine E, all intake valves 8 and exhaust valves 9 of the cylinders that can be deactivated according to the engine temperature are constituted by engine valves that are deactivated by a valve deactivation mechanism 30 and are hydraulically controlled. The valve 56 is configured so that the slide pin 32 occupies the valve operating position when the engine temperature is equal to or lower than the predetermined temperature in the warm-up state of the internal combustion engine E, and when the engine temperature exceeds the predetermined temperature, When the engine temperature is equal to or lower than the predetermined temperature by controlling the hydraulic pressure of the hydraulic oil so as to be able to occupy the valve rest position, the internal combustion engine E is operated by the full cylinder operation in which all the cylinders 1a are operated. Therefore, the startability of the internal combustion engine E and the startability of the motorcycle are improved, and warming up of the internal combustion engine E is promoted. When the engine temperature exceeds the predetermined temperature, the internal combustion engine E is operated by the partial cylinder operation in which the cylinder that can be deactivated is deactivated, so that fuel efficiency is improved.

Hereinafter, an embodiment in which a part of the configuration of the above-described embodiment is changed will be described with respect to the changed configuration.
The internal combustion engine is provided with a plurality of intake valves or a plurality of exhaust valves for one cylinder, and some of the intake valves or exhaust valves are in a stopped state by a valve stop mechanism. It may be an institution.
The hydraulic oil supplied to the valve deactivation mechanism may be supplied by an oil pump driven by power other than the power of the internal combustion engine, for example, an electric oil pump, or from a hydraulic source that can be in a low hydraulic pressure state other than the oil pump. It may be supplied.
An internal combustion engine may be used for machines other than vehicles.

It is principal part sectional drawing in the plane orthogonal to the rotation center line of a cam shaft of an internal combustion engine provided with the valve operating apparatus with which this invention was applied. It is a principal part enlarged view of FIG. 1, (a) is a figure when the slide pin of a valve deactivation mechanism occupies a valve operation position, (b) is a figure when the slide pin of a valve deactivation mechanism occupies a valve deactivation position. It is a figure of time. It is a disassembled perspective view of the valve stop mechanism of the valve operating apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cylinder block, 2 ... Cylinder head, 8 ... Intake valve, 9 ... Exhaust valve, 20 ... Valve-operating device, 21, 22 ... Cam shaft, 23 ... Valve lifter, 30 ... Valve rest mechanism, 31 ... Holder, 32 ... Slide Pin, 32a, 32b ... end, 33 ... control spring, 43 ... insertion hole, 44 ... hydraulic chamber, 45 ... storage chamber, 46 ... communication hole,
E: Internal combustion engine, Av, Ap: Axial direction.

Claims (2)

A cam follower (23) driven by a valve-operating cam (21a, 22a) provided on the cam shaft (21, 22), and a valve pause mechanism (30) provided on the cam follower (23) for putting the engine valve in a pause state The valve operating mechanism (20) of the internal combustion engine (E) includes the cam follower (23) and the engine follower (8, 9) in conjunction with the cam follower ( A valve operating position for transmitting the valve driving force of the valve cam (21a, 22a) transmitted to 23) to the engine valve (8, 9), the cam follower (23), and the engine valve (8, 9); The actuating element (32) that moves between the valve resting position where the valve driving force transmitted to the cam follower (23) is not transmitted to the engine valve (8, 9), Based on the hydraulic pressure, a resilient force that opposes the hydraulic driving force acting on the operating element (32). In the valve operating device (20) of the internal combustion engine (E), comprising a resilient means (33) for acting on the operating element (32),
The actuating element (32) occupies the valve operating position by the elastic force, occupies the valve rest position by the hydraulic driving force,
The hydraulic driving force is a driving force by hydraulic oil discharged from an oil pump (55) driven by a crankshaft,
The valve pause mechanism (30) includes a holder (31) that slidably supports the operating element (32), and the operating element (32) has a hydraulic oil acting section (where the hydraulic driving force acts) 32a), a transmission part (32d) for transmitting the valve driving force transmitted through the cam follower (23) to the engine valve (8, 9), and the valve drive to the engine valve (8, 9). A space portion (42, 43) that does not transmit force and a resilient side acting portion (32b) on which the resilient force acts are provided, and the actuating element (32) is configured so that the transmitting portion ( 32d), the cam follower (23) and the engine valve (8, 9) are interlocked, and the cam follower (23) and the engine valve (8, 9), and the hydraulic oil side action part (32a) and the transmission part (32d) Is arranged to face said space portion (42, 43) sandwiched therebetween in the direction of movement of the child (32),
The impact-side action portion (32b) is adjacent to the transmission portion (32d) on the opposite side of the space portion (42, 43) in the moving direction and accommodates the impact member (33). (45) is formed, and the operating element (32) communicates with the space portions (42, 43) and the storage chamber (45) at a position overlapping the transmission portion (32d) in the moving direction. passage (46) is provided, and, in Rukoto are notches formed in the cam shaft (21, 22) inboard end (32 b) of the space portion provided in the actuating element (32) (43), wherein The valve operating device for an internal combustion engine, wherein the actuating element (32) is movable to the valve rest position even at an idling rotational speed including a cranking rotational speed at the time of starting the engine . The internal combustion engine (E) includes a multi-cylinder internal combustion engine (1a) having a plurality of cylinders (1a) including a cylinder capable of being switched between an operation state and a suspension state according to an engine temperature, and an operation cylinder which is always in an operation state. E), and all the intake valves (8) and exhaust valves (9) of the restable cylinder are constituted by the engine valves (8, 9) brought into a rest state by the valve rest mechanism (30), hydraulic pressure of the hydraulic fluid is controlled in accordance with the engine temperature by the oil pressure control valve provided in the hydraulic control system (57) (56), the hydraulic control valve (56), the engine temperature is the internal combustion engine (E ) So that the operating element (32) occupies the valve operating position when the temperature is below a predetermined temperature in the warm-up state, and the operating element (32) is the valve when the engine temperature exceeds the predetermined temperature. Occupy a rest position So as to allow the door, valve operating system for an internal combustion engine according to claim 1, characterized in that to control the hydraulic pressure of the hydraulic fluid.

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