JP2002070514A - Electromagnetic driving device for valve body of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem in an electromagnetic driving device for deriving the opening/closing of the suction valve that the device itself is enlarged if the valve element lifting amount of a suction valve or the like is formed to be adjusted by changing the position of an electromagnetic coil wound on an iron core for driving a moving piece. SOLUTION: This electromgnetic driving device for a valve element of an internal combustion engine has two electromagnetic coils installed at the certain intervals in the valve shaft direction of the valve element of the internal combustion engine, the electromagnetic force generating when voltage is applied to the electromagnetic coils is acted to a moving piece locating between the electromagnetic coils, and the valve element of the internal combustion engine is driven with a driving shaft to which the moving piece is fixed. The moving piece is composed of at least two pieces having different thickness, and a driving shaft selecting means for selectively acting one driving shaft of the driving shafts to which each moving piece is individually fixed to the valve element is installed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve body electromagnetic drive device for driving, for example, an intake valve and an exhaust valve of an internal combustion engine for an automobile.

[0002]

2. Description of the Related Art Conventionally, there has been known a valve body electromagnetic drive device that drives an intake valve or an exhaust valve, which is a valve body of an internal combustion engine, by using an electromagnetic force generated by an electromagnetic coil. This type of electromagnetic drive device for a valve element includes an iron core, an electromagnetic coil wound around the iron core, a movable element that reciprocates by an electromagnetic force generated in the electromagnetic coil, and a reciprocating movable element fixed to the iron element. The apparatus includes a drive shaft movably supported to open and close the intake and exhaust valves, and a displacement sensor for detecting a movement position of the drive shaft.

In recent years, an engine called variable valve timing in which the opening timing of an intake valve or an exhaust valve and the lift amount thereof are variable has been put to practical use. In order to realize such a configuration in which the lift amount of the valve body at the variable valve timing can be changed in the valve body electromagnetic drive device, the valve body electromagnetic drive device is disclosed in, for example, JP-A-8-1.
No. 89315, the first and second electromagnetic coils are provided in the axial direction of the valve body, and the second electromagnetic coil is provided by hydraulic pressure.
There is known an electromagnetic coil in which a lift amount of a valve body is changed by displacing an electromagnetic coil in a valve axis direction.

[0004]

However, in the case where the electromagnetic coil is displaced as in the above-mentioned publication, it is necessary to move a relatively large iron core around which the electromagnetic coil is wound. The device configuration for that purpose becomes large and the structure becomes complicated. As a result, the valve body electromagnetic drive device itself becomes large, and the balance with the engine is reduced. In addition, since the iron core must be moved, responsiveness is reduced.

[0005] An object of the present invention is to solve such a problem.

[0006]

In order to achieve the above object, the present invention takes the following measures. That is, the electromagnetic drive device for a valve body of an internal combustion engine according to the present invention is provided with two electromagnetic coils at intervals in the valve axis direction of the valve body of the internal combustion engine, and when a voltage is applied to the electromagnetic coil. An electromagnetic drive device for an internal combustion engine that drives an electromagnetic force to act on a mover located between the electromagnetic coils and drives a valve body of the internal combustion engine by a drive shaft to which the mover is attached, wherein the mover is It is characterized by comprising a drive shaft selecting means comprising at least two drive shafts having mutually different thicknesses and each of which has a movable member to which one of the drive shafts is individually attached to selectively acts on the valve element.

With such a configuration, the movable range of the mover is different due to the different thickness of the mover,
Therefore, the movable range of the drive shaft also differs for each drive shaft. Therefore, one of the plurality of drive shafts is selected by the drive shaft selection means, and the selected drive shaft acts on the valve body, so that the movable range defined by the thickness of the mover attached to the selected drive shaft It becomes possible to adjust the movable range of the valve element, that is, the valve element lift amount corresponding to each case. As described above, in the combination of the plurality of movers and the drive shaft, only one of them is selected to act on the valve body, so that the configuration can be simplified.

The specific structure of the drive shaft selecting means is as follows.
A shaft holder having a recess in which the drive shaft selecting means is fitted with an end portion of each drive shaft in a state where a gap is formed in the axial direction near the shaft end of the drive shaft; and a gap formed in the recess. And a spacer which is removably inserted into the housing. According to such a configuration, the drive shaft can be selected by inserting the spacer into the gap formed in the concave portion, and the selection can be made easily and reliably.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

First, a first embodiment will be described with reference to FIGS. An electromagnetic drive device for a valve body, that is, an electromagnetic actuator 100 shown in FIG. 1 drives an intake valve (exhaust valve) V, which is a valve body of an engine for an automobile as an internal combustion engine, and is attached to a cylinder head. In this embodiment, an engine having two intake valves V at an intake port will be described.

The electromagnetic actuator 100 penetrates the core 1 including the first core member 11 located on the upper side and the second core member 12 located on the lower side, and the first core member 11 and the second core member 12. A first drive shaft DS1 and a second drive shaft DS2, which are vertically movably disposed, and a first drive shaft DS1
Armature P1 (armature) fixed to
A second mover P2 fixed to a second drive shaft DS2 having a thickness smaller than the thickness of the mover P1, a first drive shaft DS1 and a second
An upper shaft holder 2 having a recess 21 for individually fitting the upper ends of the drive shafts DS2, a lower shaft holder 3 having a recess 31 for individually fitting the lower ends of the first drive shaft DS1 and the second drive shaft DS2, The first drive shaft DS1 and the second drive shaft DS can be interposed in the respective concave portions 21 and 31 when they are interposed.
2 and a coil spring CS for urging the first and second drive shafts DS1 and DS2 in the direction in which the intake valve V opens. In this embodiment, the first drive shaft DS1 is composed of two axes that are arranged in parallel and perform the same operation. The upper shaft holder 2, the lower shaft holder 3, and the spacer 4 constitute a drive shaft selecting means.

An electromagnetic coil (not shown) is wound around each of the first iron core member 11 and the second iron core member 12, and is fixed to be spaced apart in the valve axial direction of the intake valve V to form the iron core 1. . That is, the first core member 11 and the second core member 1
Reference numeral 2 denotes a space provided between the lower surface of the first core member 11 and the upper surface of the second core member 12, in which the first mover P1 and the second mover P2 move. . The first core member 11 and the second core member 12 are connected to the first drive shaft D
A central through hole THa and a side through hole THb for inserting the S1 and the second drive shaft DS2 are provided. The central through hole THa is provided at a central portion of the iron core 1 in the width direction.
The side through holes THb are provided in parallel on both sides of the center through hole THa. The center through hole THa and the side through hole T
The distance between Hb and the first mover P1 fixed to the first drive shaft DS1 and the second mover P fixed to the second drive shaft DS2
2 are set so that they can be arranged in parallel without contact.

The first drive shaft DS1 and the second drive shaft D inserted into the center through hole THa and the side through hole THb.
S2 and the second drive shaft DS2 is the first drive shaft DS2.
It is shorter than the drive shaft DS1. The second drive shaft DS2 is inserted into the center through hole THa so as to be able to reciprocate, and the first drive shaft DS1 is inserted into the side through hole THb so as to be able to reciprocate.

The first mover P1 fixed to the first drive shaft DS1 and the second mover P2 fixed to the second drive shaft DS2 are arranged in the longitudinal direction of the first drive shaft DS1 and the second drive shaft DS2. It is fixed approximately at the center, and in the neutral state shown in FIG.
They are arranged so that their centers in the thickness direction are aligned. That is, the first mover P1 and the second mover P2 are arranged in parallel in a direction orthogonal to the valve axis of the intake valve V.

The upper shaft holder 2 and the lower shaft holder 3 include:
Corresponding to the position of the central through hole THa and the side through hole THb, concave portions 21 and 31 are provided in which the upper and lower ends of the first drive shaft DS1 and the second drive shaft DS2 fit. The upper shaft holder 2 and the lower shaft holder 3 are arranged such that both ends of the first drive shaft DS1 are in the axial direction in the recesses 21 and 31 with the spacer 4 inserted into the recess 21 in which the first drive shaft DS1 is fitted. (In the vertical direction), they are fitted without forming a gap.
The upper shaft holder 2 is urged by a coil spring CS in a direction in which the intake valve V is opened. Shaft lower holder 3
Has a flat bottom surface, so that the drive force of the first drive shaft DS1 (second drive shaft DS2) is transmitted evenly to the two intake valves V.

Referring to FIG. 4, a specific configuration of the spacer 4 constituting the drive shaft selecting means will be described with reference to the upper shaft holder 2. That is, the spacer 4 can be moved by hydraulic pressure and can be moved by hydraulic pressure into the gap Sp formed between the axial end of the first drive shaft DS1 (second drive shaft DS2) and the recess 21. Has become. That is, the spacer 4
Is mounted so as to be able to reciprocate within the concave portion 21, and in a state where no hydraulic pressure is applied, a position where the return spring 22 does not contact the end of the first drive shaft DS <b> 1 (second drive shaft DS <b> 2), that is, the space Sp. Is stationary in the state where is formed. Then, via a hydraulic oil passage OL provided in the first drive shaft DS1 (second drive shaft DS2),
When hydraulic oil is filled in an oil chamber OC provided adjacent to the concave portion 21 and a hydraulic pressure is applied to the spacer 4 against the urging force of the return spring 22, as shown in FIG. This is inserted into Sp. In this way, when the spacer 4 is inserted into the concave portion 21, the spacer 4
As a result, the gap Sp in the recess 21 disappears, and the first drive shaft DS
Either 1 or the second drive shaft DS2 is selected.

In such a configuration, when no voltage is applied to each of the electromagnetic coils, the electromagnetic actuator 100 does not act on the first movable element P1 and the second movable element P2. The urging force of the valve body coil spring VS and the urging force of the coil spring CS that are attached to urge the intake valve V in the fully closed direction are balanced, and
The first and second movable elements P1 and P2 are stationary at the center position of the movable space 13 formed by the first iron core member 11 and the second iron core member 12 that constitute the above. In this state, the intake valve V is opened at an intermediate position between the fully closed state and the fully opened state. When a voltage is applied to the upper electromagnetic coil, the intake valve V resists the urging force of the coil spring CS and the valve body coil spring The first and second movable elements P1 and P2 are pulled upward by being biased by VS,
The drive shaft DS moves upward, and the intake valve and the like are fully closed. On the other hand, when the upper electromagnetic coil is turned off and the lower electromagnetic coil is energized, it is urged by the coil spring CS, and opposes the urging force of the valve coil spring VS. Is pulled down, and the selected drive shaft, for example, the first drive shaft DS1 pushes down the intake valve V to open it.

Here, according to FIGS. 1 to 3, the first drive shaft DS
The operation when 1 is selected will be described. In order to select the first drive shaft DS1, in the upper shaft holder 2, the spacer 4 is inserted into the recess 21 by applying a back pressure. In this state, the lower end of the first drive shaft DS1 contacts the lower shaft holder 3 without forming a gap between the axial end and the concave portion 31 in the concave portion 31 of the lower shaft holder 3. On the other hand, since the second drive shaft DS2 is shorter than the first drive shaft DS1, both ends of the second drive shaft DS2 are not in contact with any of the upper shaft holder 2 and the lower shaft holder 3 but in the concave portions 21 and 31 in the axial direction. A state is formed in which a gap is formed at the end. After the first drive shaft DS1 is selected in this way, if the electromagnetic coils of both the first core member 11 and the second core member 12 are not energized, as shown in FIG. The child P1, P2 is not attracted to any of the iron core members 11, 12, and the intake valve V is held in a half-open state. The level shown by the two-dot chain line in FIGS.
The reference position when the intake valve V is in the fully closed state is shown.

Next, when only the electromagnetic coil of the lower second core member 12 is energized, as shown in FIG.
The movers P1 and P2 are attracted to the second core member 12, and
Therefore, the first drive shaft DS1 pushes down the lower shaft holder 3, and the intake valve V is opened. Conversely, the first core member 11
3, only the first and second movers P1 and P2 are attracted to the first iron core member 11, as shown in FIG. 3, so that the first drive shaft DS1 pushes up the upper shaft holder 2 and the air is sucked. The valve V is closed by the urging force of the valve coil spring VS. Here, since the thick first mover P1 is fixed to the selected first drive shaft DS1, the movable range (stroke) of the first drive shaft DS1 is:
This is smaller than the case where the second drive shaft DS2 described below is selected.

To change the valve lift of the intake valve V,
The second drive shaft DS2 is selected instead of the first drive shaft DS1. In this case, as shown in FIGS. 5 to 7, the spacer 4 used for the first drive shaft DS <b> 1 is removed from the recess 21, and the spacers 4 are provided in the recesses 21 and 31 of both the shaft upper holder 2 and the shaft lower holder 3. Each spacer 4 is inserted. Thereby, the second drive shaft DS2 is connected to both the upper shaft holder 2 and the lower shaft holder 3 by the spacer 4 without any gap. In this state, the first and second core members 11,
In a neutral state in which no current is supplied to the twelve electromagnetic coils, as shown in FIG. 5, the intake valve V is opened at approximately half the full opening. When power is supplied only to the electromagnetic coil of the second core member 12,
As shown in FIG. 6, the first and second movers P1 and P2 are attracted to the second core member 12, and thus the second drive shaft DS
2 pushes down the lower shaft holder to open the intake valve V. Conversely, when only the electromagnetic coil of the first iron core member 11 is energized, as shown in FIG.
P2 is attracted to the first core member 11, so that the second drive shaft DS2 pushes up the upper shaft holder 2, and the intake valve V is closed by the urging force of the valve body coil spring VS.
Here, since the thin second mover P2 is fixed to the selected second drive shaft DS2, the second mover P2 becomes larger than the movable range (stroke) of the first drive shaft DS1. That is, the difference between the thickness of the first mover P1 and the thickness of the second mover P2 is the difference in the movable range between the first drive shaft DS1 and the second drive shaft DS2.

Therefore, for example, when the intake valve V is driven with the first drive shaft DS1 being selected, the fixed first mover P1 has a large thickness (thickness), and the valve body lift amount is small. It is small. Then, the hydraulic pressure acting on the spacer 4 that has selected the first drive shaft DS1 is reduced to approximately 0.
By pulling out the spacer 4 from the concave portion 21 and selecting the second drive shaft DS2 instead, the second mover P2
Limits the movable range of the second drive shaft DS2,
The movable range is increased by the difference in thickness between the first mover P1 and the second mover P2. As a result, the moving distance of the lower shaft holder 3 increases, and the valve lift of the intake valve V increases.

As described above, in order to change the valve lift of the intake valve V, the spacer 4 to be operated is selected and either the first drive shaft DS1 or the second drive shaft DS2 is moved with respect to the intake valve V. By doing so, the valve lift of the intake valve V can be changed. Moreover, the valve body lift amount can be changed only by inserting the spacer 4 into the recesses 21 and 31 at one end of the first drive shaft DS1 and the second drive shaft DS2. The mechanism for changing the amount can be simplified.

The present invention is not limited to the embodiment described above. In the above embodiment,
An electromagnetic actuator that opens and closes two intake valves may be applied to one that opens and closes one intake valve (exhaust valve). In a case where the present invention is applied to such a single intake valve (exhaust valve), for example, a first drive shaft and a second drive shaft to which movers having different thicknesses are respectively fixed are arranged separately from each other. In the center between the shaft centers of the first drive shaft and the second drive shaft,
In addition, an intake valve is disposed below the lower ends of the first drive shaft and the second drive shaft, and the first drive shaft and the second drive shaft are selectively operated by the drive shaft selecting means. May be releasably connected. In this case, the drive shaft selecting means is, for example, slidably moved at the upper end of the valve shaft of the intake valve (exhaust valve) and detachably connected to one of the lower ends of the first drive shaft and the second drive shaft. It may be configured as follows.

The thickness of the mover may be two or more. In this case, like the first drive shaft in the above embodiment, the drive shaft may be a plurality of drive shafts each having a mover of the same thickness attached to each mover. .

In addition, the configuration of each part is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0026]

As described above, according to the present invention, one of the drive shafts to which the movers having different thicknesses are attached is selected by the drive shaft selecting means, and the selected drive shaft is connected to the valve body. Since it operates, the movable range of the valve element, that is, the valve element lift amount can be adjusted in accordance with the change of the movable range of the movable element depending on the thickness of the movable element attached to the selected drive shaft. As described above, in the combination of the plurality of movers and the drive shaft, only one of them is selected to act on the valve body, so that the configuration can be simplified and the device itself can be downsized. it can.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a case where a first drive shaft is selected and first and second movers are at a neutral position in an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a case where a first drive shaft is selected and a first and a second movable element are at positions attracted to a second core member in the embodiment.

FIG. 3 is a cross-sectional view illustrating a case where the first and second movable elements are at positions attracted to a first iron core member when a first drive shaft is selected in the embodiment.

FIG. 4 is an enlarged cross-sectional view showing an attached state of the spacer in the embodiment.

FIG. 5 is a sectional view showing a case where the first and second movers are at a neutral position when a second drive shaft is selected in the embodiment.

FIG. 6 is a cross-sectional view showing a case where the first and second movable elements are at positions where they are attracted to the second core member when the second drive shaft is selected in the embodiment.

FIG. 7 is a cross-sectional view showing a case where the first and second movers are in a position attracted to the second core member when the second drive shaft is selected in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Iron core 2 ... Shaft upper holder 3 ... Shaft lower holder 4 ... Spacer DS1 ... 1st drive shaft DS2 ... 2nd drive shaft P1 ... 1st mover P2 ... 2nd mover

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3G018 AB09 AB16 BA38 CA09 CA16 CA19 DA24 DA36 DA41 DA43 DA51 DA52 DA63 DA74 EA22 FA01 FA06 FA07 FA11 GA03 GA14 3H106 DA07 DA25 DA32 DB02 DB12 DB22 DB26 DB32 DC02 DD03 EE34 EE48 FA08 GA13 GA15 KK17

Claims (2)

[Claims] An internal combustion engine is provided with two electromagnetic coils spaced from each other in a valve axis direction of a valve body, and an electromagnetic force generated when a voltage is applied to the electromagnetic coils is movable between the electromagnetic coils. An electromagnetic drive device for a valve body of an internal combustion engine, wherein the mover is made up of at least two movable members having different thicknesses. An electromagnetic drive device for a valve body of an internal combustion engine, comprising: drive shaft selection means for selectively acting one of drive shafts to which a mover is individually attached on a valve body. 2. A shaft holder having a recess in which an end of each drive shaft is fitted in a state where a gap is formed in the axial direction in the vicinity of the shaft end of the drive shaft. 2. The electromagnetic drive device for a valve body of an internal combustion engine according to claim 1, further comprising a spacer removably inserted into a gap formed in the internal combustion engine.