JP2009228590A - Air intake and exhaust valve driving system of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air intake and exhaust valve driving system of an internal combustion engine capable of realizing the considerable miniaturization of a cylinder head. <P>SOLUTION: The operational directions of plungers 61, 62 of solenoids 41, 42 are set to be different from those of an air intake valve 2 and an air exhaust valve 3. The plungers 61, 62 of the solenoids 41, 42 and valve stems 7, 8 of the air intake valve 2 and the air exhaust valve 3 are interlockingly connected to each other. Further, the positions of the intersections P1, P2 of the axes of the plungers 61, 62 with the axes of the valve stems 7, 8 of the air intake valve 2 and the air exhaust valve 3 are set to be inward of a stem end of the air intake valve 2 and stem ends of the valve stems 7, 8 of the air exhaust valve 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an intake / exhaust valve drive system for an internal combustion engine mounted on various vehicles and the like, and more particularly, to an electric intake / exhaust valve drive system capable of significantly reducing a cylinder head.

  Conventionally, an intake / exhaust valve of an internal combustion engine employs a mechanical transmission system in which a reciprocating driving force is transmitted by a camshaft that is rotationally driven by a crankshaft. However, recently, in order to improve responsiveness, a transmission system that electrically operates the intake and exhaust valves has been proposed. For example, a valve timing control mechanism for an internal combustion engine in which a swing cam is combined with a solenoid has been proposed (see, for example, Patent Document 1). In this example, a solenoid is linked to a rocker shaft integral with the swing cam, and the valve is reciprocated by sliding the swing cam driven by the reciprocation of the solenoid on the tappet. Yes. The swing cam detects the swing angle by an angle sensor, and is given confirmation (feedback) as to whether or not a predetermined valve lift is being performed.

  Further, in the intake / exhaust valve drive system configured so that the lower end of the stopper rod integrated with the armature of the electromagnetic actuator is brought into sliding contact with the rocking end of the rocker arm rocked by the cam formed on the camshaft, There has also been proposed a valve timing control apparatus for an internal combustion engine that controls the valve closing timing by temporarily holding the opened valve (see, for example, Patent Document 2). In this example, the response delay of the electromagnetic actuator is predicted, and the valve holding timing by the electromagnetic actuator is controlled based on the predicted value, thereby ensuring the reliable holding of the valve by the electromagnetic actuator and the efficient efficiency of the electromagnetic actuator. Both power saving through operation is achieved.

Further, an electromagnetic actuator is proposed in which the intake / exhaust valve is directly driven by a solenoid instead of the above-described mechanical / electrical combination type (see, for example, Patent Document 3). In this example, in order to facilitate the wiring work for the coil and reduce the manufacturing cost by sharing the wiring, the coil reciprocates between two electromagnets facing each other and spaced from each other. An armature is arranged, and the armature is directly connected to the intake valve or the exhaust valve. That is, the electromagnetic actuator is disposed immediately above the valve shaft so that the armature of the electromagnetic actuator is aligned with the axis of the valve shaft of the intake valve or the valve shaft of the exhaust valve.
JP-A-11-101109 JP 2003-293799 A JP 2001-126919 A

  In the configuration described in Patent Document 1, as shown in FIG. 1 to FIG. 6 in the same document, the axial center line of the solenoid plunger is disposed in the lateral direction perpendicular to the valve shaft, so that the solenoid body is The cylinder head protrudes to one side. For this reason, the side portion of the cylinder head protrudes in the lateral direction and becomes very bulky, and the downsizing of the engine room is significantly hindered.

  In the configuration described in Patent Document 2, the lower end of the stopper rod integrated with the armature of the electromagnetic actuator is brought into sliding contact with the rocking end of the rocker arm protruding outward from the valve shaft. Space for storage is required in the side part in the cylinder head. Therefore, also in this case, the cylinder head becomes bulky, and the downsizing of the engine room is prevented.

  The electromagnetic actuator described in Patent Document 3 is disposed at a position immediately above the valve shaft so that the axial center line of the armature coincides with the axial center line of the valve shaft of the intake valve or the exhaust valve. The electromagnetic actuator disposed at a position directly above both valve shafts protrudes so as to expand in a large V shape on both sides of the cylinder head. Accordingly, in this case as well, the cylinder head protrudes to both sides and becomes large and bulky, and the downsizing of the engine room is significantly hindered. For this reason, when a solenoid for driving the intake / exhaust valve is provided in the cylinder head, a countermeasure for making the cylinder head as compact as possible is required.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electric intake / exhaust valve drive system for an internal combustion engine in which the cylinder head can be significantly reduced in size.

  An intake / exhaust valve drive system for an internal combustion engine according to the present invention relates to an intake / exhaust valve drive system for an internal combustion engine in which a solenoid for driving an intake valve and an exhaust valve of the internal combustion engine is provided in a cylinder head. The operation direction of the solenoid plunger is set to a direction different from the operation direction of the intake valve or the exhaust valve, and the solenoid plunger and the valve shaft of the intake valve or the exhaust valve are interlocked. Link. And the position of the intersection of the axial line of the plunger and the axial line of the valve shaft of the intake valve or the valve shaft of the exhaust valve is the position of the shaft end of the valve shaft of the intake valve or the valve shaft of the exhaust valve. It is characterized by being set at a position inside the shaft end.

  According to such a configuration, the position of the intersection of the axis of the solenoid plunger and the axis of the valve shaft of the intake valve or the valve shaft of the intake valve is determined as the valve shaft of the intake valve or the valve of the exhaust valve. Since it is set at a position inside the shaft end of the shaft, the space required on the cylinder head for placing the solenoid is required closer to the inside of the cylinder head. The overhang can be avoided and the cylinder head can be made compact. Such a configuration is suitable for driving a single intake valve or exhaust valve with a single solenoid.

  The connecting means for interlockingly connecting the plunger of the solenoid and the valve shaft of the intake valve or the valve shaft of the exhaust valve has the displacement in the axial direction of the plunger as the valve shaft of the intake valve or the valve of the exhaust valve. If the direction of movement of the shaft is converted and transmitted, the reciprocating operation of the plunger can be converted to the opening / closing operation of the intake valve or the exhaust valve without waste. The connecting means may include, for example, a long hole and a mover that floats in the long hole. In this way, with a simple configuration, the displacement in the axial direction of the plunger can be converted and transmitted to the moving direction of the valve shaft of the intake valve or the valve shaft of the exhaust valve. Further, since the rocker arm can be omitted, the number of parts in the engine block can be reduced and the size can be reduced.

  An intake / exhaust valve drive system for an internal combustion engine according to the present invention includes a position of an intersection of a solenoid plunger shaft center line and an intake valve valve shaft or an exhaust valve valve shaft center line. Is set to a position inside the shaft end of the exhaust valve or the valve shaft of the exhaust valve. Therefore, the space required on the cylinder head for arranging the solenoid is required closer to the inside than the side of the cylinder head. As a result, the cylinder head can be prevented from overhanging to the side, and the cylinder head can be made compact.

  Hereinafter, embodiments of an intake / exhaust valve drive system for an internal combustion engine according to the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is an explanatory diagram showing a main configuration of an intake / exhaust valve drive system (hereinafter referred to as a valve drive system A) for an internal combustion engine. This valve drive system A is provided with two solenoids 41, 42 for driving the intake valve 2 and the exhaust valve 3 of the internal combustion engine 1 on the upper surface of the cylinder head 5, and the plungers 61, 62 of the solenoids 41, 42 are arranged. The operation direction is set to a direction different from the operation directions of the intake valve 2 and the exhaust valve 3. In other words, the plungers 61 and 62 of the solenoids 41 and 42 are disposed in the vertical direction with respect to the valve shaft 7 of the intake valve 2 and the valve shaft 8 of the exhaust valve 3 disposed so as to face each other in a substantially V shape. Is done. And the position of the intersection P1 of the axis line of one plunger 61 and the axis line of the valve shaft 7 of the intake valve 2, the axis line of the other plunger 62, and the valve axis 8 of the exhaust valve 3 The position of the intersection P2 with the shaft center line is set to a position inside the shaft end (upper end) of the valve shaft 7 of the intake valve 2 and the shaft end (upper end) of the valve shaft 8 of the exhaust valve 3 respectively. .

  Then, the lower end of the plunger 61 of one solenoid 41 is brought into contact with the upper surface of one rocker arm 91 that drives the intake valve 2, and the lower end of the plunger 62 of the other solenoid 42 is driven to the exhaust valve 3. The other rocker arm 92 is in contact with the upper surface. The base portions of the rocker arms 91 and 92 are rotatably supported in the engine block E by pin shafts p and p, respectively. Further, the intake valve 2 and the exhaust valve 3 are urged in a direction (upward) to close the valve port by coil springs s and s fitted on the upper portions of the valve shafts 7 and 8, respectively. When such a valve drive system is applied to, for example, a four-valve engine, two pairs of solenoids 4 may be provided.

  With such a configuration, when the coil c of one solenoid 41 is excited and the armature a is attracted to the coil c and the plunger 61 moves downward, the rocking end of the rocker arm 91 moves downward. 7 and the intake valve 2 are pushed down to open the intake port. When the other solenoid 42 is excited and the plunger 62 is moved downward, the rocking end of the rocker arm 92 is moved downward, so that the valve shaft 8 and the exhaust valve 3 are pushed down to open the exhaust port. Such an opening / closing operation of the intake valve 2 and the exhaust valve 3 can be performed independently by controlling and driving the solenoids 41 and 42 at appropriate timings. Therefore, not only the normal drive mode of the internal combustion engine 1 but also, for example, When the engine is running at a low speed, etc., one of the two intake valves is deactivated, so that a thin air-fuel mixture with less gasoline can be burned efficiently and fuel efficiency can be realized.

  In such a configuration, the positions of the intersections P1 and P2 between the shaft centers of the plungers 61 and 62 of the solenoids 41 and 42 and the shafts of the valve shaft 7 of the intake valve 2 and the valve shaft 8 of the exhaust valve 3 are determined. Since the valve shaft 7 of the intake valve 2 and the shaft end of the valve shaft 8 of the exhaust valve 3 are set at positions on the inner side, respectively, it is necessary on the cylinder head 5 to arrange the solenoids 41 and 42. It is possible to consolidate the space to be inward. Therefore, even if the two solenoids 41 and 42 are provided on the upper surface of the cylinder head 5, the two solenoids 4 and 4 can be covered with the compact head cover 51 without the need to project laterally. 5 can be made compact. Further, the camshaft is not necessary. The degree of freedom in opening and closing timing of the intake and exhaust valves is expanded.

(Embodiment 2)
FIG. 2 is an explanatory diagram showing a main configuration of a different valve drive system B. This valve drive system B is provided with a connecting means 9 instead of the rocker arm disposed between the plunger 61 of one solenoid 41 and the valve shaft 7 of the intake valve 2, and the plan of the other solenoid 42. A connecting means 10 is provided in place of the rocker arm disposed between the jar 62 and the valve shaft 8 of the exhaust valve 3. The connecting means 9 and 10 respectively convert the displacement in the axial direction (vertical direction) of the plungers 61 and 62 into the moving direction (oblique direction) of the valve shaft 7 of the intake valve 2 and the valve shaft 8 of the exhaust valve 3. Configured to communicate.

  Specifically, as shown in an enlarged manner, the connecting means 9 and 10 are provided with long holes 11 and 12 and floating elements 13 and 14 that float in the long holes 11 and 12, respectively. The long holes 11 and 12 are formed in the sheet metal members 15 and 16 attached to the upper portions of the valve shaft 7 and the valve shaft 8 in an inwardly fixed state. On the other hand, the sliders 13 and 14 are provided at the lower ends of the plungers 61 and 62 so as to be rotatable or fixed. With such a configuration, when one plunger 61 moves down, the intake valve 2 is pushed down while the idler 13 moves downward in the long hole 11, and the intake port opens. When the other plunger 62 moves downward, the exhaust valve 3 is pushed down while the idler 14 moves downward in the long hole 12, and the exhaust port is opened.

  According to such a configuration, as in FIG. 1, the shaft centers of the plungers 61 and 62 of the solenoids 41 and 42, and the shaft centers of the valve shaft 7 of the intake valve 2 and the valve shaft 8 of the exhaust valve 3. Since the positions of the intersections P1 and P2 are set at positions inside the shaft end of the valve shaft 7 of the intake valve 2 and the shaft end of the valve shaft 8 of the exhaust valve 3, solenoids 41 and 42 are disposed. Therefore, the space required on the cylinder head 5 can be gathered inward. Therefore, even if the two solenoids 41 and 42 are provided on the upper surface of the cylinder head 5, the cylinder head 5 can be made compact without requiring side protrusions. Further, in this example, since the bulky rocker arm can be omitted, the number of parts in the engine block E can be reduced and the size can be reduced.

  It should be noted that the present invention is not limited to the embodiment, and can be freely improved, changed, etc. as necessary without departing from the gist of the invention.

  The intake / exhaust valve drive system for an internal combustion engine according to the present invention can be made compact for a cylinder head, and therefore can be suitably applied to a vehicle or the like that requires a compact engine room.

It is explanatory drawing which shows the principal part structure of the intake / exhaust valve drive system of the internal combustion engine which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the principal part structure of the intake / exhaust valve drive system of the internal combustion engine which concerns on Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Intake valve 3 Exhaust valve 41, 42 Solenoid 5 Cylinder head 51 Head cover 61, 62 Plunger 7, 8 Valve shaft 9, 10 Connection means 11, 12 Long hole 13, 14 Slider 15, 16 Sheet metal material 91, 92 Rocker arm P1, P2 Intersection point p Pin shaft a Armature c Coil s Coil spring E Engine block

Claims (3)

An intake / exhaust valve drive system for an internal combustion engine in which a solenoid for driving an intake valve and an exhaust valve of the internal combustion engine is provided in a cylinder head,
The operation direction of the solenoid plunger is set to a direction different from the operation direction of the intake valve or the exhaust valve, and the solenoid plunger and the valve shaft of the intake valve or the exhaust valve are interlocked. The position of the intersection of the axial line of the plunger and the axial line of the valve shaft of the intake valve or the valve shaft of the exhaust valve is connected to the shaft end of the valve shaft of the intake valve or the valve shaft of the exhaust valve. An intake / exhaust valve drive system for an internal combustion engine, wherein the intake / exhaust valve drive system is set at a position inside the shaft end of the internal combustion engine.   The connecting means for interlockingly connecting the plunger of the solenoid and the valve shaft of the intake valve or the valve shaft of the exhaust valve has the displacement in the axial direction of the plunger as the valve shaft of the intake valve or the valve of the exhaust valve. 2. The intake / exhaust valve drive system for an internal combustion engine according to claim 1, wherein the transmission is converted into a moving direction of the shaft and transmitted.   The intake / exhaust valve drive system for an internal combustion engine according to claim 2, wherein the connecting means includes a long hole and an idler that floats in the long hole.

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