JP3498517B2 - solenoid valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve used as a control valve for hydraulic equipment and the like.

[0002]

2. Description of the Related Art Conventionally, there has been a solenoid valve as this type of solenoid valve as shown in FIG. Figure 5
5A is a sectional view showing a schematic structure of the solenoid valve 100, and FIG. 5B is an enlarged view of a B portion in FIG. 5A.

The solenoid valve 100 has a coil 105.
Spring 1 by the magnetic force generated by energizing the
By suctioning the plunger 106 toward the center post 104 against the biasing force of 25, the outflow ports 155 and 156 communicating with the inflow port 148 are opened to control the flow rate or pressure.

When such a solenoid valve 100 is used in an automatic transmission (AT) of an automobile, the amount of foreign matter such as abrasion powder and dust of gears and clutches is large due to the structure of the AT. It was necessary to provide an oil passage inside as a measure to prevent the accumulation of oil. Therefore, in the solenoid valve 100, the drain port 123 is opened in the axial center of the adjusting screw 120 so as to penetrate therethrough in the axial direction.

In the solenoid valve 100, in order to make the attraction force characteristic proportional to the current, the inner peripheral surface 126 of the attraction portion 114 of the center post 104 is a tapered surface that expands toward the plunger 106 side and the center of the plunger 106 is enlarged. The outer peripheral surface 132 of the end portion on the side of the post 104 is a tapered surface whose diameter is reduced on the side of the center post 104.

Further, in order to control the solenoid valve 100 proportionally, it is necessary to separate the inner peripheral surface 126 of the center post 104 and the outer peripheral surface 132 of the plunger 106 by a certain distance or more. Therefore, the center post 10
A shim 1 made of a non-magnetic material between the plunger 4 and the plunger 106.
28 is interposed. The shim 128 has a substantially cylindrical shape, and has an inner peripheral surface 12 of the suction portion 114 of the center post 104.
6 is fitted in a concave portion 127 provided at the inner diameter side end portion and is provided so as to project in the axial direction. Especially at very low temperatures (-30
If the oil viscosity increases, the shim 128
When the plunger 106 contacts with the plunger 106
Is absorbed and hysteresis occurs, so that the contact area with the plunger 106 is reduced by forming the shim 128 in a cylindrical shape.

[0007]

However, in the solenoid valve 100, since the inner peripheral surface 126 of the suction portion 114 of the center post 106 is exposed in the oil passage flowing to the drain port 123, iron powder or the like is contained in the oil. When the foreign substance made of the magnetic substance is mixed, the foreign substance 110 is adsorbed to the inner peripheral surface 126. Further, even if the foreign matter is made of a non-magnetic material, the foreign matter accumulates between the inner peripheral surface 126 and the shim 128.

When the foreign matter made of magnetic material is adsorbed on the inner peripheral surface 126 of the suction portion 114 of the center post 104, the shape of the suction portion of the center post 104 is changed, and the clearance between the suction portion 114 and the plunger 106 is changed. Therefore, there is a problem in that the suction force increases, the control characteristics change, and the durability decreases.

The present invention has been made in order to solve the problems of the prior art, and its purpose is to prevent the deterioration of the performance due to the influence of foreign matter in the oil and to improve the quality. It is in.

[0010]

In order to achieve the above object, a first aspect of the present invention is directed to a stator, a coil arranged so as to surround the stator, and detachable from the stator. A coil provided on the coil; and a biasing unit interposed between the valve and the stator for pressing the valve against a valve seat provided on the opposite side of the stator. An electromagnetic valve that separates the valve body from the valve seat by attracting the valve body to the stator side against the biasing force of the biasing means by the generated magnetic force, and the valve body side of the stator. At the end of the solenoid valve having a concave portion facing the valve body and having an inner peripheral surface that is a tapered surface that expands to the valve body side, an inner periphery that forms the tapered surface of the concave portion of the stator. Formed on the surface
The inner edge of the valve body side edge to cover the concave space
Frusto-conical with a radial end surface located, wedge-shaped in cross section, or
Alternatively, the solenoid valve is characterized in that a flange-shaped shielding member is provided in the recess .

With this structure, since the concave portion of the stator is covered with the shielding member, foreign matter does not accumulate in the concave portion, and the foreign matter made of magnetic material is attracted to the inner peripheral surface of the concave portion of the stator. Since the clearance between the stator and the valve body does not decrease, the control characteristics do not change, the durability does not decrease, and the quality improves. Further, if the shielding member is made of a non-magnetic material, it does not affect the control characteristics of the solenoid valve.

Here, the shielding member may be one that closely adheres to the inner peripheral surface of the concave portion of the stator to fill the concave portion, or one that keeps a distance from the inner peripheral surface of the concave portion to shield.

According to a second aspect of the present invention, in the first aspect of the present invention, the shielding member contacts the valve body during suction of the valve body and regulates the distance between the valve body and the stator. It is characterized by having.

With this configuration, the distance between the valve element and the stator during suction is kept constant, so that proportional control is possible. Further, if the interval regulating portion is provided integrally with the shielding member, the number of parts can be reduced and the assembling process can be simplified.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described based on the illustrated embodiments.

(First Embodiment) FIG. 1A is a sectional view showing a schematic structure of a solenoid valve 1 according to an embodiment of the present invention. FIG. 1B is an enlarged view of part A of FIG.

The schematic structure of the solenoid valve 1 as an electromagnetic valve mainly includes a solenoid 2 and a valve body 3 assembled integrally with the solenoid 2.

The solenoid 2 is roughly configured as follows: a center post 4 made of a magnetic material as a stator, a coil 5 surrounding the center post 4 and arranged coaxially, and a center post 4 inside the coil 5. It comprises a plunger 6 as a valve element arranged coaxially, and a cover plate 7 for accommodating these members and forming a magnetic path between the center post 4 and the plunger 6.

The coil 5 is wound on a resin bobbin 8 having outwardly extending flange portions 9 and 10 extending radially outward.

The center post 4 is inserted into one opening of the bobbin 8, and the under plate 1 is inserted into the other opening.
A plunger is reciprocally inserted coaxially with the center post 4 via 1. The under plate 11 is a magnetic member made up of a cylindrical portion 12 that covers a part of the outer circumference of the plunger 6 and a flange portion 13 that extends radially outward along the flange portion 10 of the bobbin 8.
Guide the magnetic path from to the plunger 6.

The center post 4 has a substantially columnar shape, and is fixed by inserting the end portion 15 on the opposite side of the suction portion 14 for sucking the plunger 6 into the hole 16 of the cover plate 7 and caulking it. Cover plate 7 around the center post 4
The portion between the bobbin 8 and the bobbin 8 is covered with a mold resin portion 17, and the mold resin portion 17 has a connector 1
8 is integrally formed. A through hole 19 is provided in the axial direction of the center post 4 in the axial direction, and a substantially columnar adjusting screw 20 is inserted therein. A threaded portion 21 is provided at the end of the inner peripheral surface of the through hole 19 on the opposite side of the plunger 6, and is screwed with a threaded portion 22 provided on the outer periphery of the adjusting screw 20.

A drain port 23 penetrating in the axial direction is provided at the axial center of the adjusting screw 20. Further, a step portion 24 is provided on the outer periphery of the end portion of the adjusting screw 20 on the plunger 6 side, and a spring 25 as an urging means is attached.

A recess facing the plunger 6 is provided at the end of the center post 4 on the suction portion 14 side. The inner peripheral surface 26 of the recess has a tapered surface on the side of the plunger 6 that expands in diameter in order to make the attraction force characteristic proportional to the current.
It is formed parallel to the tapered surface formed on the outer peripheral surface 32 at the end of the plunger 6 on the center post side. Inner peripheral surface 26
An axial recess 27 is provided at the end portion on the inner diameter side.
A hollow, generally frustoconical shim 28 made of a non-magnetic material is attached to the end of the center post 4 on the plunger 6 side.
When the plunger 6 is sucked toward the center post 4 side, the plunger 6 contacts the shim 28, so that the interval between the plunger 6 and the center post 4 is regulated to be constant and proportionally controlled. A through hole 28a is provided in the axial direction of the shim 28 in the axial direction, and the spring 25 is inserted into the through hole 28a. A projecting portion 29 that extends in the axial direction and surrounds the through hole 28a is formed at the end of the shim 28 on the small diameter side. In the mounted state, the projecting portion 29 is the axial center of the inner peripheral surface 26 of the suction portion 14 of the center post 4. The outer peripheral surface 30 is in contact with the inner peripheral surface 26 of the suction portion 14 of the center post 4 while fitting in the recess 27 formed in the side end portion. Also,
A recess 31 a is formed on the large-diameter side end surface 31 of the shim 28 to reduce the contact area with the plunger 6. In the present embodiment, the shim 28 itself constitutes a shielding member provided with the space regulating portion.

The material of the shim is a non-magnetic material as long as it operates and is durable against thermal shock.
3, 304), copper, brass, resin, etc. can be used.

The plunger 6 has a substantially columnar shape with steps. The outer peripheral surface 32 of the end portion of the large diameter portion 6a on the side of the center post 4 is a tapered surface whose diameter is reduced toward the center post 4 side.
4 is formed parallel to the inner peripheral surface 26. An axial recess 33 is formed on the center post 4 side of the large diameter portion 6a, and a spring 25 is held between the bottom surface 33a of the recess 33 and the step portion 24 of the adjusting screw 20. The small-diameter portion 6b formed at the tip on the valve body 3 side through the step portion 35 has an internal hollow cylindrical shape, and the hollow portion 37 has an opening 38 on the inflow port 48 side at the tip and near the step portion 35. Two openings 39,40 on the side
Have.

The valve sleeve 41 as a valve seat has a substantially cylindrical shape with a step, and the plunger 6 is reciprocally inserted from the opening on the large diameter portion 41a side. The medium diameter portion 41b of the valve sleeve 41 is provided with two openings 43, 44. Due to the urging force of the spring 25, the step portion 34 of the plunger 6 causes the large diameter portion 41 of the valve sleeve 41 to move.
By contacting the end portion a of the plunger 6 on the side of the plunger 6, the openings 39 and 40 of the plunger 6 are closed by the inner peripheral surface of the valve sleeve 41 and the flow path is closed. The small diameter portion 41 c of the valve sleeve 41 is fitted into the inner circumference of the valve body 3 on the side of the inflow port 48, and the tip portion 49 is open to the inflow port 48. The tip portion 49 of the valve sleeve 41 is caulked and fixed by a stopper 51 fitted in a circumferential groove 50 on the inner circumference of the valve body 3, and the step portion 52 abuts on the step portion 53 on the inner circumference of the valve body 3. There is.

The valve body 3 has a substantially hollow cylindrical shape and has an opening 5 at an axial end thereof which forms an inflow port 48.
4, and the outflow ports 55 and 56 for communicating the inside and the outside are provided at positions substantially corresponding to the openings 43 and 44 of the valve sleeve 41 on the side surface in the axial direction. In this embodiment, the outflow port 55 is also connected to the drain. A circumferential groove 57 is provided on the outer circumference of the end portion on the inflow port 48 side, and O is provided for sealing when the inflow port 48 side is connected.
A ring 58 is attached.

These members are integrally housed in a substantially cylindrical cover 59. One end of the cover 59 is fixed to the outer periphery of the cover plate 7 by caulking, and the inflow port 48 side of the valve body 3 is opened from the opening 61 provided through the inward flange portion 60 of the other end. Exposed.

In the solenoid valve 1, foreign matter is prevented from accumulating by discharging it together with oil from the drain port 23. However, the shim 28 is formed into a hollow truncated cone shape and the center post 4 has a suction portion 14 side. Since the concave portion at the end is covered, oil containing foreign matter does not enter the space formed between the shim and the center post 4 unlike the conventional case. Therefore, the foreign matter of the magnetic body is not adsorbed to the inner peripheral surface of the recess of the end portion of the center post 4 on the suction portion 14 side, and the clearance between the center post 4 and the plunger 6 is not reduced, so that the control characteristic is changed, The quality is improved without lowering the durability.

Further, since the concave portion at the end of the center post 4 on the suction portion 14 side is covered only by the shim 28, it is not necessary to separately provide a shielding member, and the number of parts can be reduced and the assembling process can be simplified.

Further, the recess 3 is formed on the large diameter end surface 31 of the shim.
2 is formed and the contact area with the plunger 6 is small, so that the plunger 6 is not adsorbed by the shim 28 due to the increase in the viscosity of the oil even at an extremely low temperature (about -30 to 0 ° C). Therefore, the hysteresis can be reduced and the quality can be improved.

In the present embodiment, the shim has a substantially frustoconical shape, but the shim is not limited to such a shape as long as it can cover the inner peripheral surface 26 of the recess of the center post 4 on the suction section 14 side. is not.

Further, in this embodiment, the center post 4 is used.
The recessed portion on the suction portion side end and the end portion of the plunger 6 on the center post 4 side are tapered surfaces, but the shape is not limited to this and any shape having parallel surfaces facing each other may be used. The attraction force characteristic can be made proportional to the current.

(Other Embodiments) FIGS. 3 and 4 are enlarged views of the vicinity of the suction portion of the solenoid valve according to another embodiment of the present invention. Since the configuration other than the shim and the shielding member is the same as that of the first embodiment, the description thereof will be omitted.

As shown in FIG. 3, between the inner peripheral surface 26 of the recess of the end of the center post 4 on the suction portion 14 side and the substantially cylindrical shim 62, a non-magnetic wedge-shaped annular shield member is formed. 63 is inserted. With this configuration, since the concave portion of the end of the center post 4 on the suction portion 14 side is covered by the shielding member 63, foreign matter enters or accumulates in the space between the concave inner peripheral surface 26 and the shim 62, or The foreign matter of the magnetic material is not adsorbed to the inner peripheral surface 26 of the recess of the post 4. Therefore, the quality is improved without changing the control characteristics and reducing the durability.

As shown in FIG. 4, a flange portion 65 extending in the outer diameter direction and reaching the end portion of the center post 4 is provided on the end portion of the shim 64 of a non-magnetic material having a substantially cylindrical shape on the plunger 6 side. There is. In this way, the recess at the end of the center post 4 on the suction portion 14 side is covered by the shim 64, so that foreign matter enters or accumulates in the space between the inner peripheral surface 26 of the recess and the shim 64, or Inner peripheral surface 2 of 4
No foreign matter of the magnetic material is adsorbed on the magnetic disk 6. Further, when the plunger 6 is sucked toward the center post 4 side, the plunger 6 abuts the shim 64, so that the interval between the plunger 6 and the center post 4 is regulated to be constant and proportionally controlled. In the present embodiment, the shim 64 itself constitutes a shielding member provided with a space regulating portion.

A projecting portion 65a projecting in the direction of the plunger 6 is formed on the axial center side of the end portion of the shim 64 on the plunger 6 side. When the plunger 6 is sucked toward the center post 4, the plunger 6 projects. Since the contact area with the shim 64 is small due to the contact with the portion 65a, the plunger 6 is not adsorbed by the shim 64 due to the increase in the viscosity of the oil even at an extremely low temperature (about -30 to 0 ° C). Therefore, since the hysteresis can be reduced, the quality can be improved.

[0038]

As described above, according to the first aspect of the present invention, since the concave portion of the stator is covered with the shielding member, foreign matter is not accumulated in the concave portion, and particularly foreign matter made of magnetic material is fixed. Since the clearance between the stator and the valve element is not reduced by being adsorbed on the inner peripheral surface of the concave portion of the child, the control characteristics are not changed, the durability is not deteriorated, and the quality is improved. Further, if the shielding member is made of a non-magnetic material, it does not affect the control characteristics of the solenoid valve.

According to the second aspect of the invention, since the distance between the valve element and the stator during suction is kept constant, proportional control is possible. In addition, if the interval regulating portion is integrally provided on the shielding member,
The number of parts is reduced and the assembly process is simplified.

[Brief description of drawings]

FIG. 1A is a sectional view showing a schematic structure of a solenoid valve according to a first embodiment of the present invention. Figure 1
FIG. 1B is an enlarged view of part A of FIG.

FIG. 2 is a sectional view of a shim of the solenoid valve according to the first embodiment of the present invention.

FIG. 3 is an enlarged view around a suction portion of a solenoid valve according to another embodiment of the present invention.

FIG. 4 is an enlarged view around a suction portion of a solenoid valve according to another embodiment of the present invention.

FIG. 5 (a) is a sectional view showing a schematic structure of a conventional solenoid valve. FIG. 5B is an enlarged view of part B of FIG.

[Explanation of symbols]

1,100 solenoid valve 4,104 center post 5,105 coils 6,106 Plunger 41 valve sleeve 14,114 Suction section 26,126 Inner surface 32,132 outer peripheral surface 28,62,64,128 shims 63 Shielding member

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16K 31/06

Claims (2)

(57) [Claims] 1. A stator, a coil arranged so as to surround the stator, a valve body provided so as to be capable of coming into contact with and separating from the stator, and interposed between the valve body and the stator. Urging means for pressing the valve body against a valve seat provided on the opposite side of the stator, and the valve body is resisted against the urging force of the urging means by the magnetic force generated in the coil. An electromagnetic valve that separates the valve body from the valve seat by suctioning to the stator side, the end portion of the stator on the valve body side, facing the valve body,
Further, in an electromagnetic valve having an inner peripheral surface having a tapered concave portion whose diameter increases toward the valve body side, the electromagnetic valve is formed by a tapered inner peripheral surface of the concave portion of the stator.
So as to cover the concave space, it is located on the valve body side end edge of the inner peripheral surface
Frusto-conical shape with radial end faces, wedge-shaped cross section, or
A solenoid valve, wherein a flange-shaped shielding member is provided in the recess . 2. The shielding member is provided with an interval restricting portion that abuts against the valve element when the valve element is sucked to restrict an interval between the valve element and the stator. 1. The solenoid valve according to 1.