JP2001065319A - Electromagnetic driving valve device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability and workability for a core and to reduce material cost in an electromagnetic driving valve device related to an electromagnetic driving valve, and particularly, an electromagnetic driving valve device provided with the magnetic core. SOLUTION: The core 35 is made of steel plate which has magnetism and strength and a dust material which is weaker in strength as compared with steel plate, having excellent moldability and material cost. The core 35 stores an electromagnetic coil 36. By disposing the steel plate at a portion on which an armature main body 21 and the core 35 are abutted, displacement of the core 35 by friction when the core 35 collides against the armature main body 21 is reduced. At the inside of the steel plate, the dust material with excellent moldability and material cost is filled into steel plate to is mold the core 35. Because the dust material and the steel plate are simultaneously worked by heating and pressurizing when the core 35 is molded, manufacturing cost when the core 35 is molded can be reduced. As a result, durability and workability of the core 35 and material cost can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromagnetically driven valve, and more particularly to an electromagnetically driven valve device having a magnetic core.

[0002]

2. Description of the Related Art In general, an electromagnetically driven valve comprises an armature for driving a valve element and an electromagnetic core for sucking the armature. When the electromagnetic core is excited, the armature is attracted toward the electromagnetic core by the electromagnetic force. Then, the electromagnetically driven valve is opened and closed by driving the valve body according to the displacement of the armature. The electromagnetic core includes a core made of a magnetic material and a coil housed inside the core. When the excitation state of the electromagnetic core changes, an eddy current is generated in the core. The eddy current generated in the core acts to cancel the electromagnetic force generated by the electromagnetic core. Therefore,
In order to ensure the performance of the electromagnetically driven valve, it is required to suppress the eddy current generated in the core.

As a configuration capable of reducing an eddy current generated in a core, for example, Japanese Unexamined Patent Application Publication No. 10-332
A core disclosed in Japanese Patent No. 027 is known. The above-mentioned conventional core is formed by laminating a plurality of magnetic plates in a spiral shape in a circumferential direction. According to such a configuration, the resistance to the eddy current is increased by stacking a plurality of magnetic plates in the direction of the eddy current generated in the core, that is, in the circumferential direction of the core. As a result, the eddy current generated in the core is reduced. Is suppressed. Further, durability is improved by forming a gap between the armature and the core by a contact member provided on the electromagnetic core. By applying the above-described conventional core configuration to the electromagnetic core of an electromagnetically driven valve, it is possible to prevent the performance of the electromagnetically driven valve from being degraded due to eddy currents in the core, and to provide an electromagnetically driven valve device having excellent durability. I will provide a.

[0004]

However, in the above-mentioned prior art, a steel sheet is used as a core to form a laminated structure in order to suppress eddy current. However, the manufacturing cost and the material cost are high and the strength of the steel sheet is strong. Little freedom in shape. For this reason, there is a problem in that it is subject to design restrictions when mounted on the housing of the electromagnetically driven valve.

[0005] In view of the above problems, there is a powdered material excellent in moldability and production cost. However, there is a problem that the powdered material has a lower strength and is brittle than a steel plate.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and according to the electromagnetically driven valve device of the first aspect, the first core portion has a high durability. 1 member and a second member having lower durability and better moldability than the first member.
Formed by the above members. Further, since the first member is provided at a position where the mover main body and the first core portion are in contact with each other, displacement of the first core portion due to wear can be suppressed, and durability can be improved. it can. In addition, by disposing the second member having good moldability at a portion other than the portion where the mover main body and the first core portion are in contact with each other, the moldability of the first core portion is improved, and the degree of freedom in design is improved. Can be improved.

Further, the second core portion is made of a highly durable second core.
And a fourth member having lower durability and better moldability than the third member. Further, since the first member is provided at a position where the mover main body and the first core portion are in contact with each other, displacement of the second core portion due to wear can be suppressed, and durability can be improved. it can. In addition, by disposing the second member having good moldability at a portion other than the portion where the mover main body and the second core portion are in contact with each other, the moldability of the second core portion is improved, and the design is free. The degree can be improved.

According to the second aspect of the present invention, the first member comprises a bottom wall, a side wall, and an opening facing the mover main body, and the second member comprises a powder material. Consisting of
The first core portion is formed by filling a first member with a powder material, and applying heat and pressure.

The third member comprises a bottom wall, a side wall, and an opening facing the mover main body, the fourth member comprises a powder material, and the second core comprises a third core. Since the members are simultaneously formed by filling a powder material into the members and heating and pressurizing, the configuration of the second core portion can reduce the manufacturing cost and the material cost.

[0010] In general, the cost of a powder material is lower than that of a steel sheet, so that the cost can be reduced.

As described above, according to the first and second aspects of the present invention, the first member and the powder material or the third
The magnetic core, which combines the above materials and powder material, maintains the durability of the core compared to the conventional technology, and further improves the manufacturing cost, material cost, and the degree of freedom of design, thereby improving workability, cost, and durability. An object of the present invention is to provide an excellent electromagnetic core.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; (Embodiment) FIGS. 1 to 4 show an electromagnetically driven valve device for an internal combustion engine according to an embodiment of the present invention. The electromagnetically driven valve device 10 of the embodiment
Reference numeral 0 denotes an electromagnetically driven valve device that drives an intake valve of an internal combustion engine by electromagnetic force. FIG. 1 shows a state in which the valve body 1 is half-opened when no power is supplied, FIG. 2 shows a valve closed state in which the upper coil 31 is energized, FIG. 3 shows a valve open state in which the lower coil 36 is energized, and FIG. Indicates a configuration of a core unit that generates an electromagnetic force.

The electromagnetically driven valve 1 shown in FIGS. 1 to 3 is controlled at a predetermined timing to open and close an intake port 3 for supplying fuel and air to a combustion chamber 2 of an engine. The electromagnetically driven valve 1 is moved up and down in the axial direction by a stem 11 formed to extend toward a spring accommodating chamber 40 formed in the engine block 4. The electromagnetically driven valve 1 is slidably held on the engine block 4 by a stem guide 5 for guiding the movement in the axial direction. The engine block 4 is formed with an oil supply passage 67 communicating with an oil passage 66 described later. The oil supply passage 67 is connected to an oil pump 110 described later via an oil passage (not shown).

A first spring 41 as a first urging means and a second spring 71 as a second urging means are accommodated in the spring accommodating chamber 40. One end of the first spring 41 has an inner bottom surface 65 of a spring groove 64 formed in a lower housing 63 described later.
, And the other end thereof is in contact with the retainer 42 as a holding member. Since the retainer 42 is fixed to an end of an armature shaft 22 described later by a cotter 45, the first spring 41 urges the valve body 1 in the valve opening direction. Also, Apparitainer 4
2, a convex portion 43 that can be brought into contact with a damper piston 96 described later and a concave portion 44 that is fitted to a convex portion 73 of a lower retainer 72 described later are formed.

The second spring 71 has one end in contact with a lower retainer 72 as a holding member, and the other end in contact with the inner bottom surface 46 of the spring accommodating chamber 40.
Since the lower retainer 72 is fixed to the end of the stem 11 of the valve body 1 by the cotter 75, the second spring 71 urges the valve body 1 in the valve closing direction.
The lower retainer 72 is formed with a convex portion 73 that fits into the concave portion 44 of the upper retainer 42. here,
The gap between the convex portion 73 of the lower retainer 72 and the concave portion 44 of the appendage retainer 42 is formed smaller than the mounting gap between the lower housing 63 and the inner wall of the engine block 4 forming the spring accommodating chamber 40. Therefore, the convex portion 73 of the lower retainer 72 and the concave portion 44 of the
“Constitutes a guide portion that prevents the stem 11 of the valve body 1 and the axis of the armature shaft 22 from tilting and reduces sliding resistance.

The housing 60 comprises a cylindrical upper housing 61, a cylindrical middle housing 62, and a cylindrical lower housing 63.
0 and is fixedly fitted to the inner wall of the engine block 4. The armature 20 is housed in the housing 60.
, An upper core 30 as a first stator, a lower core 35 as a second stator, a shaft guide 80 as a bearing, and damper pistons 91 and 96 are accommodated.

The armature 20 as a mover is composed of an armature main body 21 as a mover main body and an armature shaft 22 as a mover shaft. The upper core 30 and the lower core 35 are guided by a shaft guide 80 for guiding the movement in the axial direction. Is slidably supported with respect to. The armature body 21 is disposed between the upper core 30 and the lower core 35, and is made of a magnetic material such as a cylindrical iron. Further, the armature main body 21 has a convex portion 24 that can contact the damper piston 91.

One end of the armature shaft 22 as a mover shaft is fitted into the armature main body 21, and the end on the engine block 4 side is an retainer 42.
The valve body 1 is connected to the end of the stem 11 of the valve body 1 via a lower retainer 72 so as to be in contact with the stem 11. A clearance is provided between the applicator retainer 42 and the lower retainer 72. Thereby, even if the total length of the stem 11 and the armature shaft 22 changes due to thermal expansion, a certain length is maintained by the clearance.
The armature shaft 22 is made of, for example, stainless steel and has grooves 23 and 27 formed on the outer wall in the axial direction. A plurality of grooves 23 and 27 are formed on the outer wall of the armature shaft 22,
And is connected to an oil supply passage 81 formed at zero. By supplying oil to the grooves 23 and 27,
The sliding resistance between the armature shaft 22 and the shaft guide 80 can be reduced, and oil can be supplied to the damper piston 91.

The first stator has an upper core 30 as a first core and an upper coil 31 as a first coil.
It is composed of In addition, the external member 32 is a bottom wall 3
In the present embodiment, it is formed by pressing a single steel plate. The inner member 33 is formed by filling a powder material into the outer member, and further pressurizing and heating.

The bottom wall portion 32a shown here corresponds to a portion where the armature 20 abuts on the upper core 30. If this abutting portion is a bottom wall portion 32a, the side surface is a side wall portion 32b.
An opening 33c is located at a position symmetrical to the bottom wall.

The upper coil 31 is disposed inside the upper core 30. When the upper coil 31 is energized, the upper core 30 attracts the armature body 21 and generates an electromagnetic force for moving the armature 20 and the valve body 1 in the valve closing direction.

The second stator comprises a lower core 35 as a second core portion and a lower coil 36 as a second coil portion. And the lower housing 6
3 housed.

FIG. 4 shows a detailed view of the lower core 35. The lower core 35 includes an external member 32 'made of a steel plate made of magnetic material such as iron as a third member, and an internal member 33' made of a powder material as a second member. Since the powder material is composed of iron powder and resin, the resin formed in the gap between the iron powder and the iron powder has an effect of preventing eddy current. Further, the powder material can be easily formed into a core having an arbitrary shape by melting the resin by applying pressure and heating. Lower core 35
Is composed of an inner member 33 'and an outer member 32' as a powder material having the above-mentioned characteristics.

The outer member 32 'includes an upper wall 32'a, a side wall 32'b, and an opening bottom 32'c. In the present embodiment, the outer member 32' is formed by pressing a single steel plate. The inner member 33 'fills the inside of the outer member 32' with a powder material,
It is formed by further pressing and heating.

The upper wall portion 32'a shown here corresponds to a portion where the armature 20 abuts on the lower core 35. If this abutting portion is an upper wall portion 32'a, the side surface is a side wall portion 32 '.
b, a position symmetrical to the upper wall portion 32'a is defined as an opening bottom portion 32'c.

The lower coil 36 is disposed inside the lower core 35. When the lower coil 36 is energized,
The lower core 35 sucks the armature body 21 and generates an electromagnetic force for moving the armature 20 and the valve body 1 in the valve opening direction.

A middle housing 62 is provided between the upper core 30 and the lower core 35. The movement of the armature 20 is restricted by the thickness of the middle housing 62.

The shaft guide 80 supports the armature shaft 22 slidably in the axial direction. The shaft guide 80 includes an oil passage 66 formed in the lower housing 63 and the grooves 23 and 2 of the armature shaft 22.
And an oil supply path 81 communicating with the oil supply path 7. By supplying the oil to the oil supply path 81, the sliding between the shaft guide 80 and the armature shaft 22 is improved.

The damper pistons 91 and 96 are provided to face each other in the axial direction of the shaft guide 80. The damper piston 91 is provided at one end of the shaft guide 80 and exerts a damper function immediately before the armature main body 21 is seated on the lower core 35. The damper piston 96 is provided at the other end of the shaft guide 80. Immediately before the armature main body 21 is seated on the upper core 30, a damper function is exhibited. The damper pistons 91 and 96 are slidably supported in the axial direction by a shaft guide 80, and each of the projections 24 and the retainer 42 of the armature main body 21 at predetermined positions.
Can be brought into contact with the convex portion 43. Also, the shaft guide 8
Damper stoppers 93 and 98 are provided at both ends of the “0”, and the amount of movement of the damper pistons 91 and 96 is regulated.

An outer wall of the armature shaft 22, an inner wall of the shaft guide 80, and an outer wall of the damper piston 91 form a damper chamber 94. As shown in FIG. Shaft 22
The oil is supplied to the damper chamber 94 via the oil supply passage 81, the oil passage 66, and the oil supply passage 67. Further, a damper chamber 99 is formed by the outer wall of the armature shaft 22, the inner wall of the shaft guide 80, and the outer wall of the damper piston 96. As shown in FIG. 22 grooves 23 and 2
7, the oil is supplied to the damper chamber 99 via the oil supply path 81, the oil path 66, and the oil supply path 67.

A concave portion 92 is formed at one end of the damper piston 91, and the end surface of the convex portion 24 of the armature body 21 can abut on the inner bottom surface of the concave portion 92 when the valve is opened. Therefore, immediately before the projection 24 of the armature main body 21 collides with the damper piston 91, a damping force is generated by the oil stored in the recess 92.

In the electromagnetically driven valve device 100 having the above-described configuration, when the upper coil 31 and the lower coil 36 are not energized, the armature main body 21 is connected to the upper core 30 and the lower core 3.
5 so that the first spring 41
The set load of the second spring 71 is adjusted. At this time, the valve body 1 is in a half-open state as shown in FIG. Then, during operation of the engine, the upper coil 31 and the lower coil 36 are alternately energized, and the valve closed state and the valve open state are repeated.

Next, the operation of the damper pistons 91 and 96 and the effect of the present invention will be described.

When the valve is opened, the projection 24 of the armature body collides with the damper piston 91 immediately before the armature body 21 is seated on the lower core 35 as shown in FIG. At this time, a damper action is generated by the oil stored in the damper chamber 94. Further, the damping force at which the damper function is exerted by the oil stored in the recess 92 is gradually increased. Therefore, the armature main body 21 is
Can be prevented from colliding directly with each other to generate a loud impact sound or damage to the armature main body 21 and the lower core 35. At this time, the damper chamber 99 communicates with the grooves 23 and 27 of the armature shaft 22, and the oil is supplied to the damper chamber 99 via the oil supply path 81, the oil path 66, and the oil supply path 67.

When the valve is fully opened, the armature body 21 directly collides with the lower core 35.
The external member 32 made of a steel plate such as iron
Is provided, the displacement of the lower core 35 due to wear or the like can be reduced, and a decrease in performance due to the displacement can be suppressed.

When the valve is closed, as shown in FIG. 3, just before the armature main body 21 is seated on the upper core 30, the convex portion 43 of the retainer 42 collides with the damper piston 96. At this time, a damper action is generated by the oil stored in the damper chamber 99. Accordingly, it is possible to prevent the armature main body 21 from directly colliding with the upper core 30 to generate a loud impact sound, or to prevent the armature main body 21 and the upper core 30 from being damaged. At this time, the damper chamber 94 is in the groove 23 of the armature shaft 22.
And 27, the oil is supplied to the damper chamber 94 via the oil supply path 81, the oil path 66, and the oil supply path 112.

When the valve is fully opened, the armature main body 21 directly collides with the upper core 30. The portion where the armature main body 21 collides with the outer member 3 made of a steel plate such as iron is used.
2, the upper core 30 due to abrasion or the like.
, And a decrease in performance due to the displacement can be suppressed.

In the embodiment of the present invention described above,
The upper core 30, the lower core 35, and the armature 20 are cylindrical. Therefore, the first and second springs 41
Even when a rotational force is generated in the armature 20 due to the expansion and contraction of the armature 20 and the armature 20, the armature 20 does not come into contact with the housing 60 during the reciprocating movement of the armature 20 and the valve body 1.

Further, since the dust material made of iron powder and resin used as the internal member 33 has a structure in which resin is formed in the gap between the iron powder and the iron powder, molding is easy, and Has an effect of suppressing eddy currents.
Further, the powder material is a member having a characteristic that the material cost is lower than that of the steel plate. By using the above-mentioned powder material for the internal member 33, the material cost is reduced as compared with a conventional electromagnetic core in which steel plates are laminated, the eddy current generated in the upper core 30 or the lower core 35 is reduced, and mounting is performed because of ease of forming. The degree of freedom can be given. In addition, a strong steel plate having a structure as shown in FIG. 4 is disposed at a contact portion with the armature 20 by the forming means 1 and the forming means 2 shown in the present embodiment, so that the durability of the upper core 30 or the lower core 35 is improved. In addition, when forming the inner member and the outer member, only the heating and pressing are performed, so that the manufacturing cost can be suppressed lower than that of the conventional steel sheet laminated structure.

In the present embodiment, the first stator and the second stator use a compacted material and a steel plate. However, the first stator and the second stator use an electromagnetic core. Different materials may be used. Further, the first constituent means and the second constituent means are not limited to those shown in FIG.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a non-energized state of an electromagnetically driven valve device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a state of the electromagnetically driven valve device according to the embodiment of the present invention when the valve is closed.

FIG. 3 is a longitudinal sectional view showing a state of the electromagnetically driven valve device according to the embodiment of the present invention when the valve is opened.

FIG. 4 is a main enlarged view of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve body 20 Armature (movable element) 21 Armature main body 22 Armature shaft (movable element shaft) 30 Upper core (first stator) 31 Upper coil (first coil part) 32 External member (first member) 32a Bottom wall Part 32b Side wall part 32c Opening part 33 Internal member (second member) 35 Lower core (second stator) 36 Lower coil (second coil part) 32 'External member (third member) 32'a Upper wall part 32'b Side wall portion 32'c Open bottom 33 'Internal member (fourth member) 41 First spring (first biasing means) 42 Apparitainer 71 Second spring (second biasing means) 72 Lower retainer 84 Oil supply path 91, 96 Damper piston 96 Damper chamber 100 Electromagnetically driven valve device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yurio Nomura 1-1-1, Showa-cho, Kariya-shi, Aichi F-term in DENSO Corporation (Reference) 3H106 DA07 DA25 DB02 DB12 DB26 DB32 DC02 DD03 EE30 EE48 GA30 KK17 5E048 AA08 AB01 AD07 CA04

Claims (2)

[Claims] 1. A valve body of an intake valve or an exhaust valve of an internal combustion engine having a variable valve timing device using electromagnetic force for an intake / exhaust valve, a movable shaft connected to the valve body, and a magnetic material. A movable element having a movable element main body, a first coil section for generating an electromagnetic force, and a first core section formed of a magnetic material. A first stator for moving the mover in the valve closing direction; and a second coil portion that is disposed opposite to the first stator with the mover body interposed therebetween and generates an electromagnetic force. A second stator made of a material, a second stator for attracting the mover body by electromagnetic force to move the valve body and the mover in the valve opening direction, and the valve body or Said A first urging means for urging the moving element in the valve opening direction; and a second urging means disposed opposite to the first urging means for urging the valve body or the movable element in the valve closing direction. And a housing for accommodating the mover, the first stator, and the second stator, wherein the first core portion has a highly durable first member; A second member having a lower durability than the first member and having good moldability, wherein the first member is disposed at a position where the mover main body and the first core portion are in contact with each other; The second core portion includes a third member having high durability and a fourth member having low durability and good moldability than the third member,
The electromagnetically driven valve device for an internal combustion engine, wherein the third member is provided at a position where the mover main body and the second core portion are in contact with each other. 2. The first member includes a bottom wall, a side wall, and an opening facing the movable element main body, and the second member is formed of a powder material. The core portion is formed by filling the first member with the powder material, heating and pressurizing, and the third member has a bottom wall portion and a side wall portion facing the mover body. An opening portion, wherein the fourth member is formed of a powder material, and the second core portion is configured such that a third member is filled with the powder material, and is heated and pressed. The electromagnetically driven valve device for an internal combustion engine according to claim 1, wherein the electromagnetically driven valve device is formed by: