JPH05196165A - Solenoid valve - Google Patents

Abstract

PURPOSE: In a solenoid valve, to reduce introduction of contaminant particles into the needle chamber, to enable simple production from cheap materials, and to make the life of the valve long-lasting. CONSTITUTION: The needle 58 is composed of at least two parts 59, 60 of different size. The bottom surface of the part 60 which enters the needle chamber is made smaller than that of the part 59 which meets the valve seat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a solenoid valve having a magnetic mover guided in a mover chamber filled with a pressure medium, the mover entering the mover chamber. And a valve body adapted to abut on a valve seat.

[0002]

2. Description of the Related Art Electromagnetic valves of this type are well known in a number of structures, and are used as pressure regulating valves in automatic transmissions of automobiles. In such a type of solenoid valve, in order to damp the movement of the mover, the mover chamber of the solenoid valve is already filled with the pressure medium (oil) during normal assembly. Since the volume of the mover chamber changes during the movement of the mover, it is necessary to compensate for the volume or pressure in such a solenoid valve. Usually, such volume or pressure compensation is performed at the armature or valve member of the solenoid valve. If a solenoid valve of this type is fitted to an automatic transmission as already mentioned, then a volume or pressure compensation can take place, for example, with a chamber filled with transmission oil. However, this tends to contaminate the solenoid valve and especially the mover chamber. This can lead to valve failure, especially if it is contaminated with ferromagnetic particles. Further, if the volume or pressure of the valve member is compensated, the valve member of the solenoid valve may be locked.

A solenoid valve provided with a rod-shaped valve member cooperating with a flat armature is, for example, German Utility Model No. 88.
No. 09143 is known. The armature chamber of this known solenoid valve is filled with oil. As the armature moves, volume compensation is provided through the annular gap between the valve member and the wall of the bore that guides the valve member. However, during operation, particularly ferromagnetic contaminant particles may collect in the mover chamber. In some cases, these contaminant particles can limit the useful life of solenoid valves.

[0004]

SUMMARY OF THE INVENTION The object of the invention is to improve the solenoid valve mentioned at the outset to eliminate the disadvantages of the known art and to reduce the amount of contaminant particles brought into the armature chamber. It is an object of the present invention to provide a solenoid valve which has a long life and is easily manufactured from an inexpensive material.

[0005]

In order to solve this problem, in the structure of the present invention, the valve body is composed of at least two sections having different sizes, and is adapted to enter the movable chamber. The bottom of the section was made smaller than the bottom of the section cooperating with the valve seat.

[0006]

The solenoid valve of the present invention having the above-described structure has extremely low sensitivity to contaminants. There is also a slight tendency for locking of the valve body and deterioration of valve operability due to the accumulation of ferromagnetic contaminant particles. The solenoid valve according to the invention is easy to assemble, inexpensive to manufacture and has a long service life. The solenoid valve according to the invention is also particularly suitable for use in relatively strongly contaminated pressure medium circuits.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings.

The solenoid valve 10 has a substantially cup-shaped magnet casing 11, and a cylindrical protruding portion 13 arranged at the center projects from the bottom 12 of the magnet casing 11. A coil frame body 14 having a coil 15 is arranged around the protruding portion, and is embedded by injection molding in a plastic body 16 for the purpose of sealing and fixing. A connector body 18 also made of plastic is arranged on the outer surface 17 of the bottom portion 12. The connection contact of this connector body 18 is in contact with the coil 15 in a format not shown.

The projection 13 is penetrated by a hole 20 in the longitudinal direction. The end of the hole 20 on the bottom 12 side is configured as a screw hole 20 a and is closed by an adjusting screw 21. The adjusting screw 21 is provided with a cover (not shown) for sealing.

Below the coil frame 14, a mover chamber 22 is formed in the magnet casing 11. In the mover chamber 22, a mover 23 configured as a disk-shaped flat mover in the illustrated embodiment and elastically supported
Is provided. The mover is pierced by a hole 24 in the center, and the upper and lower surfaces 25 and 26 of the mover have annular collars 27 and 28 extending around the hole 24.
Have one each.

The inner edge 2 on the free end face side of the upper brim 27
A diaphragm spring 30 having a flow portion is in contact with 9. The outer edge 31 of the diaphragm spring 30 is
While maintaining a distance from the coil frame body 14, it is in contact with an annular shoulder portion 32 provided on the wall portion of the magnet casing 11. The outer edge 31 of the diaphragm spring 30 is pressed against the annular shoulder 32 by the spacer ring 34. The inner diameter of the spacer ring 34 is larger than the outer diameter of the mover 23. The inner edge 29 of the diaphragm spring 30 is clamped between the upper collar 27 of the armature and the flange-like closing plate 35 of the bearing pin 36. The bearing pin 36 extends through the hole 24. The closing plate 35 penetrates into the cylindrical recess 37. This recess 37 is the protrusion 1
3 is arranged around the hole 20 on the free end face side.

A plug-like guide 39 is attached to the center of the free end surface 38 of the closing plate 35. This plug-like guide 39
Is surrounded and grasped by one end of the compression spring 40 in the hole 20 which abuts the closing plate 35. The other end of the compression spring 40 is in contact with the adjusting screw 21.

The inner edge 42 of the second diaphragm spring 43 is in contact with the lower brim 28 of the mover 23.
The second diaphragm spring 43 also has a flow portion, and the outer edge 44 of the diaphragm spring 43 is in contact with the spacer ring 34. The inner edge 42 of the second diaphragm spring 43 is pressed against the lower collar 28 of the mover 23 by means of a fixing ring 45 cooperating with the bearing pin 36.

Outer edge 4 of the second diaphragm spring 43
4 is pressed against the spacer ring 34 by the fixed flange 46 of the valve connection 47. The valve connection 47 is rigidly and immovably connected to the magnet casing 11 by edging a lower section of the magnet casing 11, which is configured as a curving edge 48.

Fixed flange 4 provided on the valve connecting portion 47
A cylindrical concave portion 50 is formed on the end surface of the movable element 23 on the movable element 23 side. The diameter of the recess 50 is equal to the spacer ring 34.
Almost matches the inner diameter of. The fixing flange 46 is pierced by a longitudinal hole arranged in the center and stepped in two stages. This vertical hole projects into the valve connecting portion 47, and the hole section of the vertical hole starts from the recess 50 and is denoted by reference numeral 5.
2a to 52c are attached. The hole section 52c is connected to the coaxially extending hole 53. This hole 53 departs from the free end face 54 of the valve connection 47,
Connected to 5.

The transition from the hole section 52b to the hole section 52c serves as the valve seat 56, and the two cylindrical section 5
It cooperates with the end surface 57 of the valve body 58 consisting of 9,60. The larger diameter cylindrical section 59 has a valve seat 56 at the end face 57.
Collaborate with. For that purpose the diameter of the cylindrical section 59 is
In the present embodiment, it is formed to be slightly larger than the diameter of the valve seat 56 configured as a flat valve seat.

The valve body 58 is guided in a smaller diameter cylindrical section 60 into a longitudinal bore 62 provided in a cylindrical guide insert 63. This guide insert is fitted in the hole section 52a. The cylindrical section 60 projects into the armature chamber 22 and cooperates with the free end surface 61 of the bearing pin 36.

The hole section 52b is penetrated by a lateral hole 65, which is connected to a tank (not shown). A reference numeral T is attached to a connecting portion with the tank. The pressure conduit 55 is connected to the pressure medium source P via a throttle 66. A consumer connecting conduit 68 branches from the pressure conduit 55 between the throttle 66 and the hole 53.
The consumer connection conduit 68 leads to a consumer (not shown), the connection to which is labeled A.

The solenoid valve 10 is mounted in a hydraulic bridge circuit as an electrically adjustable pressure adjusting valve connected to the throttle 66. The pressure in the consumer connection conduit 68 is equal to the pressure when the pressing force applied from the pressure conduit 55 to the valve body 58 and the force of the compression spring 40 acting on the valve body 58 via the bearing pin 36 are balanced. equal. Coil 1
When 5 is energized, the mover 23 is attracted against the action of the compression spring 40. Valve body 58 by compression spring 40
Is reduced by the magnetic force acting on the mover 23. Therefore, the pressure conduit 55 required to balance this force
The pressing force applied to the valve body 58 via the valve is also reduced. That is, the pressure in the consumer connection conduit 68 drops. With such a solenoid valve, a falling exciting current-pressure characteristic curve is realized.

The mover chamber 22 of the solenoid valve is filled with a pressure medium in order to damp the movement of the mover during assembly. The diaphragm springs 30 and 43 have a flow passage part, and a pressure medium can flow through this flow passage part. This ensures a complete filling of the armature chamber.

During operation, the mover 23 makes an adjustment motion according to an electrical set target value. At that time, the end surface of the valve element 58 on the mover side is always in contact with the support pin 36 due to the action of the pressure generated on the end surface 57 on the opposite side. That is, when the mover 23 moves toward the connector body 18, the valve body 58 is pushed into the mover chamber. The amount of oil displaced by the valve body reaches the pressure medium-filled bore section 52b via an annular chamber provided between the valve body 58 and the wall of the bore 62 of the guide insert 63. When the mover returns to its original direction or moves toward the valve connection 47, the volume of the mover chamber increases in response to the movement of the valve body, so that the pressure medium flows back through the annular chamber. Be done.
Therefore, the pressure medium always flows in the mover chamber.

This pressure medium is partly strongly contaminated by the ferromagnetic particles resulting from the wear of the rotating parts in particular due to the connection with the pressure medium source P. The ferromagnetic contaminant particles are collected in the movable air chamber where the magnetic field is highest, that is, in the working air gap. The amount of pressure medium flowing in and out through the annular gap corresponds to the amount displaced by the valve body in the armature chamber. That is, the pressure medium in the mover chamber 22 is increased or decreased by the amount obtained by multiplying the bottom area of the invading valve body by the stroke of the valve body. In the conventional solenoid valve, the diameter of the valve member or valve body is substantially equal to the diameter of the valve seat or seat surface.

When a conventionally known solenoid valve is mounted on, for example, an automatic transmission, the diameter of the valve body of the solenoid valve is about 5 mm. Due to the above-mentioned configuration of the valve body 58, that is, the stepped configuration, the amount displaced by the valve body is significantly reduced. Reducing the diameter of the section 60 of the smaller diameter cylinder to, for example, 2 mm reduces the displacement in the movable chamber by a factor of 6 or more. Of course, the amount of contaminant particles brought into the movable chamber is correspondingly reduced.

The solenoid valve according to the invention, unlike conventional solenoid valves, requires an additional guide insert 63,
This guide insert 63 is a significantly simpler component to manufacture. Since the valve element 58 and the armature 23 are not fixedly connected, no special requirements are made regarding the material selection for the guide insert 63. Unlike conventional plain bearings, the guide insert does not have to be manufactured from a special material. Furthermore, since the magnetic lateral force ceases to act on the valve body due to the disengagement of the connection between the mover 23 and the valve body 58, for this reason as well, it is special for the quality of the valve body bearing portion. The request does not have to be made. Therefore, the valve body and the guide insert can be manufactured from inexpensive materials. In particular, the same material can be used for both components, so that the annular gap between the valve body 58 and the hole 62 also does not expand or contract due to temperature changes. In conventional solenoid valves, the annular gap shrinks as the temperature varies. This is because the valve body and the guide insert or slide bearing are manufactured from different materials. However, the reduction of the annular gap may cause the valve body to become immobile due to contaminant particles formed therein.

The structure of the valve body according to the present invention is not limited to the solenoid valve having the flat movable element guided by the diaphragm spring as shown in the above embodiment.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a solenoid valve.

[Explanation of symbols]

10 solenoid valve, 11 magnet casing, 12
Bottom part, 13 projecting parts, 14 coil frame body, 15
Coil, 16 plastic body, 17 outer surface, 1
8 connector body, 20 holes, 20a screw holes, 2
1 adjustment screw, 22 mover chamber, 23 mover,
24 holes, 25 upper surface, 26 lower surface, 27 brim, 28 brim, 29 inner edge, 30 diaphragm spring, 31 outer edge, 32 annular shoulder,
34 spacer ring, 35 closing plate, 36 bearing pin, 37 recess, 38 end face, 39 plug-shaped guide, 40 compression spring, 42 inner edge, 43 diaphragm spring, 44 outer edge, 45 fixing ring, 46 fixing flange, 47 valve connection, 48
Bending edge, 50 recess, 52a hole section, 52b
Hole section, 52c hole section, 53 hole, 54 end surface, 55 pressure conduit, 56 valve seat, 57 end surface,
58 valve body, 59 section, 60 section, 61 end face, 62 longitudinal hole, 63 guide insert 65 lateral hole, 66 throttle, 68 consumer connection conduit,
A connection part, P pressure medium source, T connection part

Claims (6)

[Claims] 1. An electromagnetic valve having a magnetic mover (23) guided in a mover chamber (22) filled with a pressure medium, the mover being provided in the mover chamber. In the type in which the valve body (58) is adapted to come into contact with the valve seat (56) in cooperation with the valve body (58), the valve body (58) has a large size. The section (59), which comprises at least two sections (59, 60) of different heights, the bottom surface of the section (60) adapted to project into the movable chamber cooperates with the valve seat. A solenoid valve that is smaller than the bottom surface of. 2. The solenoid valve according to claim 1, wherein the section (59, 60) of each of the valve bodies (58) is cylindrically formed. 3. The section (60) of the valve body (58) adapted to rush into the armature chamber (22) and having a small bottom area is guided by a guide insert (63). The solenoid valve according to claim 1 or 2, which is provided. 4. The mover chamber (22) is provided with the valve body (5).
8) and another chamber (52) filled with a pressure medium via an annular chamber between the guide insert (63) and the hole (62).
The solenoid valve according to any one of claims 1 to 3, which is connected to b). 5. The solenoid valve according to claim 1, wherein the magnetic armature (23) is embodied as a flat armature. 6. The flat movable element comprises a magnet casing (11) formed by a diaphragm spring (30, 43).
The solenoid valve according to claim 5, wherein the solenoid valve is guided therein.