JPH0960514A - Valve system for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate seating speed control while reducing a holding current when an engine valve is closed, by storing a valve closing side electromagnet, energized in the direction separating from an armature by spring tension, movably in a housing, and providing an adjusting member with a position advanceable/retreatable in the housing. SOLUTION: An engine valve 5 is attracted in both directions of closing/ opening of the valve by both electromagnets 9, 10 on the closing/opening side of the valve through an armature 8, and energized in both directions of closing/ opening of the valve by the first and both second springs 11, 121 , 122 . Here, a contact member 21 consisting of a wearing resistant material is fixedly provided in the central part of a connecting plate part 16a of the electromagnet 9 on the closing side for the valve. On the other hand, in the upper end closed part center of a housing 7, a tappet screw 22 serving as an adjusting member capable of coming into contact with the contact member 21 is advanceably/ retractably screwed. When no current is carried in both the electromagnets 9, 10, the tappet screw 22 is brought into contact with the contact member 21, and a position in the housing 7 of the electromagnet 9 on the valve closing side is adjusted so as to advance/retract.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an armature fixed to an engine valve, and an electromagnetic force, which is arranged opposite to one side of the armature and which actuates the engine valve in a valve closing direction when energized, exerts a closing force on the armature. A valve-side electromagnet, a valve-opening electromagnet, which is arranged opposite to the other side of the armature and exerts an electromagnetic force on the armature, which energizes the armature when energized, and biases the armature in the valve-closing direction. Internal combustion including a first spring and a second spring that exerts a spring force for urging the armature in the valve opening direction and cooperates with the first spring to hold the armature in a neutral position when the electromagnets are not energized. The present invention relates to a valve train of an engine.

[0002]

2. Description of the Related Art Conventionally, such a device is disclosed in, for example, US Pat. No. 3,882,833 and International Application WO WO.
It is already known from 95/00959 and the like.

[0003]

SUMMARY OF THE INVENTION In the above conventional one,
The valve-closing side electromagnet and the valve-opening side electromagnet are fixedly arranged so as to face each other on both sides of the armature, and in order to obtain a reliable valve seating state of the engine valve, the valve-closing side electromagnet and the armature are closed when the engine valve is closed. It is necessary to set a clearance between them, and to keep the electromagnetic force exerted by the valve-closing electromagnet relatively large in order to hold the engine valve, that is, the armature in the valve closing position, the current supplied to the valve-closing electromagnet should be relatively large. I have to make it bigger. The speed control when the engine valve is seated is performed by adjusting the current supplied to the valve-closing electromagnet, but in the region where the gap between the valve-closing electromagnet and the armature is very small, the electromagnetic force is sensitive to changes in the current. It is difficult to precisely control the attracting electromagnetic force of the valve closing electromagnet.

The present invention has been made in view of the above circumstances, and a valve operating valve for an internal combustion engine that reduces holding current when the engine valve is closed, facilitates seating speed control, and reduces seating noise. The purpose is to provide a device.

[0005]

In order to achieve the above object, the invention according to claim 1 is characterized in that an armature fixed to an engine valve and an engine valve which is arranged to face one side of the armature and is energized. A valve-closing electromagnet that exerts an electromagnetic force that operates in the valve-closing direction on the armature, and a valve-opening that exerts an electromagnetic force that opposes the other side of the armature and operates the engine valve in the valve-opening direction when energized. A side electromagnet, a first spring for urging the armature in a valve closing direction, and a spring force for urging the armature in a valve opening direction are exerted, and cooperate with the first spring when both electromagnets are not energized. A valve operating system for an internal combustion engine, comprising: a second spring that holds the armature in a neutral position; and a valve closing side that is biased in a direction away from the armature by a spring force of the second spring. A magnet is movably accommodated in a fixed housing, and the housing closes the position of the valve-closing electromagnet by contacting the valve-closing electromagnet when the valve-closing electromagnet and the valve-opening electromagnet are not energized. It is characterized in that an adjusting member that can move forward and backward is provided.

The invention according to claim 2 is the above-mentioned claim 1.
In addition to the structure of the invention described above, a first spring is contracted between an armature and a valve opening side electromagnet that is movably accommodated in a housing, and a movement of the valve opening side electromagnet due to a spring force of the first spring is prevented. It is characterized in that a shim is sandwiched between a fixed restricting portion provided in the housing for restricting and the valve opening side electromagnet.

According to a third aspect of the present invention, in addition to the structure of the first or second aspect of the invention, a gap is formed in the housing between the adjusting member and the electromagnet on the valve closing side when the engine valve is seated closed. It is characterized in that an adjusting hole for adjusting is provided.

Further, the invention according to claim 4 is characterized in that, in addition to the structure of the invention according to claim 1 or 2, a plurality of second springs formed in a coil shape are concentrically arranged in parallel. To do.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

1 and 2 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a valve operating system with an engine valve in a neutral position, and FIG. 2 is a valve seated state. 2 is a longitudinal sectional view corresponding to FIG. 1.

First, in FIG. 1, a cylinder head 1 is provided with a valve seat 3 having a valve opening 2 opened in the center thereof facing a combustion chamber 4, and as a suction valve or an exhaust valve which can be seated on the valve seat 3. The engine valve 5 is driven to open and close by the valve operating device according to the present invention.

This valve operating device includes a housing 7 made of a non-magnetic material fixedly mounted on the cylinder head 1, and an armature 8 fixed to the stem 5a of the engine valve 5 and movably accommodated in the housing 7. , A valve-closing side electromagnet 9 arranged in the housing 7 so as to be able to exert an electromagnetic force that attracts the armature 8 to close the engine valve 5, and the armature 8 is attracted to open the engine valve 5. A valve-opening side electromagnet 10 that is arranged in the housing 7 so as to be capable of exerting an electromagnetic force, a first spring 11 that biases the armature 8 toward the valve-closing direction of the engine valve 5, and a valve-opening direction of the engine valve 5. Pair of second springs 1 for biasing the armature 8 toward
2 ₁ and 12 ₂ .

The housing 7 is formed in a cylindrical shape with its lower end opened and its upper end closed. The housing 7 is formed on the upper surface of the cylinder head 1 so as to form a working chamber 14 between it and the upper surface. Be combined. The stem 5 a of the engine valve 5 is a guide tube 1 fixed to the cylinder head 1.
5 is slidably fitted into the working chamber 14 and is projected into the working chamber 14. In the working chamber 14, the disc-shaped armature 8 is fixed to the stem 5a. That is, an annular engagement groove 5b is provided at the end of the stem 5a, and the armature 8 is fixed to the stem 5a by the cotter 13 which is split in half and engages with the engagement groove 5b. Thus, the cotter 13 is made of a non-magnetic material in order to prevent the magnetic flux from leaking from the armature 8 to the side of the stem 5a made of a ferromagnetic material.

The valve-closing side electromagnet 9 has a substantially U-shaped cross section open to the upper surface side of the armature 8, and a coil 17 is housed in a yoke 16 formed in a ring shape coaxial with the stem 5a. A disc-shaped connecting plate portion 16a is integrally provided on the inner edge of the upper end of the yoke 16, and the outer peripheral surface of the yoke 16 is brought into sliding contact with the inner peripheral surface of the housing 7 to close the valve-closing electromagnet 9 Is slidably fitted on the top of the housing 7. Further, the valve-opening side electromagnet 10 has a substantially U-shaped cross section open to the lower surface side of the armature 8, and a coil 19 is housed in a ring-shaped yoke 18 that coaxially surrounds the stem 5a. The yoke 18 is integrally provided with a receiving portion 18a connected to the inner edge of the lower end of the yoke 18, and the valve-opening electromagnet 10 is provided so that the outer peripheral surface of the yoke 18 is brought into sliding contact with the inner peripheral surface of the housing 7. It is slidably fitted to the lower part of 7. Moreover, in the working chamber 14, the upper surface of the cylinder head 1 functions as a restricting portion 1a that restricts the movement of the valve opening side electromagnet 10 on the side away from the armature 8, and the restricting portion 1a and the valve opening side electromagnet. Shim 24 is sandwiched between 10 and 10.

The first spring 11 and the pair of second springs 1
Each of 2 ₁ and 12 ₂ is formed in a coil shape, and the first spring 11 has a valve opening side electromagnet 10 in the working chamber 14.
The second springs 12 ₁ and 12 _{2 that} are concentrically arranged between the receiving portion 18a of the armature 8 and the armature 8 are
The cap 20 attached to the end portion of a and the connecting plate portion 16a of the valve-closing side electromagnet 9 are contracted in parallel.

An abutment member 21 made of a wear resistant material is fixedly provided at the center of the connecting plate portion 16a of the valve-closing electromagnet 9, and an abutment member 21 is provided at the center of the upper end closed portion of the housing 7. A tappet screw 22 as an adjusting member capable of abutting on 21 is screwed in such a manner that it can be moved back and forth.
A nut 23 that abuts on the upper end closed portion of the housing 7 and holds the advancing / retreating position of the tappet screw 22 is screwed to the protruding portion of the housing 7. Then tappet screw 22
As shown in FIG. 1, when the valve-closing electromagnet 9 and the valve-opening electromagnet 10 are not energized, the valve-contacting electromagnet 9 comes into contact with the contact member 21 of the valve-closing electromagnet 9 in the housing 7 of the valve-closing electromagnet 9. The position is adjusted so that it can move back and forth. Further, when the engine valve 5 is seated closed, as shown in FIG. 2, there is a gap (tappet clearance) between the contact member 21 and the tappet screw 22.
26 is generated, and an adjusting hole for adjusting the gap 26 by inserting a shim (not shown) between the abutting member 21 and the tappet screw 22 when the engine valve 5 is seated closed in the upper portion of the housing 7. 25 are provided.

The operation of this embodiment will now be described. When the energization of the valve-closing electromagnet 9 is started with the armature 8 in the neutral position, the armature 8 is attracted by the valve-closing electromagnet 9. Second spring 12 ₁ , 12 ₂
The valve-closing electromagnet 9 moves toward the armature 8 side against the spring force of the second springs 12 ₁ and 12 ₂ due to the suction reaction force of the armature 8 due to its suction reaction force. The valve-closing side electromagnet 9 contacts. Thus, the valve-closing electromagnet 9
After the contact between the armature 8 and the armature 8, the engine valve 5 is moved in the valve closing direction by the relatively weak spring force of the first spring 11 and seated on the valve seat 3. Therefore, the load in the valve closing direction of the engine valve 5 immediately before the valve is seated is determined by the spring force setting of the first spring 11, and the operating speed immediately before the valve is seated is controlled by mechanical load control. Therefore, the seating speed control can be performed more easily and more reliably than the energization current control of the valve-closing side electromagnet 9. Moreover, the valve-closing electromagnet 9
Contacts the armature 8 with no clearance, so that the energizing current of the valve-closing electromagnet 9 for maintaining the engine valve 5 in the valve-closed state can be set to a relatively low value.

When the energization of the valve-opening electromagnet 10 is started with the armature 8 in the neutral position, the armature 8 is attracted by the valve-opening electromagnet 10 to open the valve while compressing the first spring 11. The valve opening-side electromagnet 10 moves toward the armature 8 side against the spring force of the first spring 11 due to the attraction reaction force of the armature 8.
The valve-opening side electromagnet 10 comes into contact with. Thus, the valve closing electromagnet 1
After the contact between 0 and the armature 8, the second spring 12 ₁ ,
The relatively weak spring force of 12 ₂ causes the engine valve 5 to move to the fully open position in the valve opening direction.

As described above, when the operation of the engine valve 5 immediately before the fully closing and immediately before the fully opening is due to the free vibration of the spring, the engine valve is in accordance with the neutral position of the armature 8 when the electromagnets 9 and 10 are not energized. The operating speed of 5 changes, and the amount of current for holding the armature 8 in both electromagnets 9 and 10 changes. However, the tappet screw 22 can adjust the position of the valve-closing side electromagnet 9 in the housing 7 when the electromagnets 9 and 10 are in the non-energized state, whereby the first and second springs 11 and 12 ₁ , 12 ₂ can be adjusted to adjust the neutral position of the armature 8. Therefore, the tappet screw 22 minimizes the moving speed of the engine valve 5, the relative moving speed of the valve closing electromagnet 9 and the armature 8 and the relative moving speed of the valve opening electromagnet 10 and the armature 8 immediately before the valve is seated. The seating noise and the contact noise of the electromagnets 9 and 10 and the armature 8 can be adjusted to reduce the amount of electric current for maintaining the valve closed state and the valve opened state as much as possible. Moreover, tappet screw 22
Are those that can be effectively used even on to compensate for the load tolerance of each spring 11, 12 _1, 12 ₂ to prevent the variation in the neutral position of the armature 8.

The shim 24 sandwiched between the restricting portion 1a and the valve-opening side electromagnet 10 absorbs the dimensional error of each component of the valve operating device and keeps the actual lift amount of the engine valve 5 substantially constant. do. That is, when the valve gear is assembled, the electromagnet 1 on the valve opening side 1
0 and the regulating portion 1a with the shim 24 interposed, the stem 5
When the first spring 11 is interposed between the armature 8 connected to a and the cylinder head 1, the engine valve 5 is in a closed state in which it is seated on the valve seat 3. Therefore, the engine valve 5 may be pushed from above to measure the stroke up to the fully opened state, that is, the valve lift amount, and the shim 24 may be replaced according to the difference from the reference lift amount. At this time, if the shim 24 can be divided into a plurality of pieces in the circumferential direction, the stem 5a can be separated from the armature 8
The shim 24 can be replaced without removing it.

Further, after the shim 24 is attached, the engine valve 5 is pushed from above to move to a position corresponding to the neutral position, and the second characteristic having a load characteristic corresponding to the spring load of the first spring 11 at that time is obtained. Select springs 12 ₁ and 12 ₂ ,
Further, the valve-closing electromagnet 9 and the housing 7 are sequentially assembled. By energizing the electromagnet 9 on the valve closing side, the engine valve 5
With the valve closed and seated, the gap 26 between the tappet screw 22 and the abutment member 21 may be adjusted according to the set value. At that time, the adjustment hole 25 is provided in the housing 7, so that the adjustment is easy. Is.

In such a valve operating device, since the pair of second springs 12 ₁ and 12 ₂ are provided in parallel between the valve-closing electromagnet 9 and the cap 20, that is, the armature 8, the housing 7 or the moving member is operated. The overall height of the valve device can be made relatively low to allow a compact construction.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the claims. It is possible to do.

[0024]

As described above, according to the first aspect of the invention, the valve-closing electromagnet, which is biased by the spring force of the second spring in the direction away from the armature, is movably housed in the fixed housing. Since the housing is provided with an adjusting member that contacts the valve-closing electromagnet when the valve-closing electromagnet and the valve-opening electromagnet are not energized, the position of the valve-closing electromagnet can be moved back and forth in the housing. Seating speed control is easy and reliable by bringing the valve-closing electromagnet into contact with the armature before seating the engine valve and then mechanically closing the engine valve by spring force until it seats. In addition, by making the valve-closing electromagnet contact the armature with no clearance, the energizing current of the valve-closing electromagnet for keeping the engine valve closed can be set relatively low. It is possible to decrease the seating sound by adjusting the spring force by the adjusting member.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, a first spring is provided between the valve opening side electromagnet and the armature that are movably accommodated in the housing. Since the shim is sandwiched between the fixed restricting portion provided inside the housing and the valve opening side electromagnet, which is contracted and restricts the movement of the valve opening side electromagnet due to the spring force of the first spring,
Immediately before fully opening the engine valve, the armature is gently brought into contact with the valve-side electromagnet to reduce contact noise, and the actual lift amount of the engine valve can be adjusted to be substantially constant.

According to the third aspect of the present invention, in addition to the structure of the first or second aspect of the present invention, the housing is formed between the adjusting member and the valve-closing electromagnet when the engine valve is seated closed. Since an adjustment hole for adjusting the gap is provided,
The clearance can be easily adjusted when the valve train is assembled.

Further, according to the invention of claim 4, in addition to the structure of the invention of claim 1 or 2, a plurality of second springs formed in a coil shape are concentrically arranged in parallel. The overall height of the housing, that is, the valve operating device can be made relatively low to provide a compact structure.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a valve train with an engine valve in a neutral position.

FIG. 2 is a longitudinal sectional view corresponding to FIG. 1 in a closed valve seated state.

[Explanation of symbols]

1a ... Regulator 5 ... Engine valve 7 ... Housing 8 ... Armature 9 ... Valve-closing electromagnet 10 ... Valve-opening electromagnet 11 ... First spring 12 ₁ , 12 ₂ ... Second spring 22 ... Tapet screw as adjusting member 24 ... Shim 25 ... Adjusting hole 26 ... Gap

Claims (4)

[Claims] 1. An armature (8) fixed to an engine valve (5), and an electromagnetic force that is arranged to face one side of the armature (8) and that operates the engine valve (5) in a closing direction when energized. To the armature (8) and the electromagnetic force (9) facing the valve closing side to the other side of the armature (8) and actuating the engine valve (5) in the valve opening direction when energized. A valve opening side electromagnet (10) exerted on (8), a first spring (11) for biasing the armature (8) in a valve closing direction, and a spring force for biasing the armature (8) in a valve opening direction. And when the both electromagnets (9, 10) are not energized, the first spring (1
In a valve operating system for an internal combustion engine and a second spring to hold the neutral position (12 _1, 12 ₂₎ 1) and cooperates armature (8), a second spring of the spring (12 _1, 12 ₂₎ A valve-closing electromagnet (9) biased by a force in a direction away from the armature (8) is movably housed in a fixed housing (7), and the housing (7) has a valve-closing electromagnet (9). ) And the valve-opening side electromagnet (10) when the valve-closing side electromagnet (9) is in a non-energized state, the adjustment member (2) that allows the position of the valve-closing side electromagnet (9) in the housing (7) to move forward and backward.
2) is provided, and a valve train for an internal combustion engine. 2. A first spring (11) is contracted between a valve opening side electromagnet (10) and an armature (8) movably accommodated in a housing (7), and a first spring (11). A shim (24) is provided between the fixed restriction portion (1a) provided in the housing (7) and the valve opening side electromagnet (10) to restrict the movement of the valve opening side electromagnet (10) due to the spring force of the. The valve operating device for an internal combustion engine according to claim 1, wherein the valve operating device is sandwiched. 3. The housing (7) has an adjusting hole (2) for adjusting a gap (26) generated between the adjusting member (22) and the valve-closing side electromagnet (9) when the engine valve (5) is seated closed.
5) The valve operating system for an internal combustion engine according to claim 1 or 2, further comprising: 4. A valve operating system for an internal combustion engine according to claim ₁ , wherein a plurality of second springs (12 ₁ , 12 ₂ ) formed in a coil shape are concentrically arranged in parallel. .