JPH0613914B2 - Hydraulic solenoid valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a body, a fixed mandrel, and a ferromagnetic movable mandrel made of metal adapted to be displaced against the action of a restoring force of a spring through a magnetic field generated by an exciting current. And a hydraulic solenoid valve having: The ferromagnetic mandrel constitutes an occluding device that cooperates with the valve seat to control fluid flow through the valve. The closure device forms an annular sealing surface with the valve seat in the closed position of the valve.

Valves of the type that can be supplied with variable frequency current are also known. For valves operating at high frequencies, the mass and stroke of the moving mandrel must be relatively weak. Similarly, the annular sealing surface should be as small as possible in order to be able to reduce the force exerted on the closure device required to close the valve. However, reducing the size of the annular seal surface entails the disadvantage that the obturator and valve seat are rapidly worn away by repeated strikes. Therefore,
The life of the valve is extremely short.

The object of the invention is to eliminate this drawback, the object being to be displaced against the action of the restoring force of the spring through the body, the fixed mandrel and the magnetic field generated by the exciting current. A hydraulic solenoid valve that includes a ferromagnetic movable mandrel made of metal, the ferromagnetic movable mandrel constituting an occlusion device that cooperates with a valve seat to control fluid flow through the valve, the occlusion device comprising: In a hydraulic solenoid valve, which forms an annular sealing surface with the valve seat in the closed position of the valve,
The hydraulic solenoid valve includes a shock absorber consisting of at least one second annular surface separated radially outwardly from the annular sealing surface by an annular throat, the second annular surfaces correspondingly arranged. Cooperates with the portion to form an annular dampening surface, the annular dampening surface being positioned proximate the corresponding portion when the closure device is in contact with the valve seat, the At least one annular throat
A hydraulic solenoid valve according to the invention characterized in that it is in communication with the outlet pipe of the valve through one passage.

In fact, when the valve closes, the fluid between the second annular surface and the corresponding part has to escape radially so that only a thin film forms at the end of the stroke. This produces a gradual braking effect on the movable mandrel before the closure device comes into contact with the valve seat.

The accompanying drawings show schematically two embodiments and variants of the valve according to the invention as an implementation.

The valve shown in FIG. 1 has a cylindrical casing 1 of ferromagnetic material. The casing 1 and the inner cylindrical portion 2 are integral,
The ferromagnetic movable mandrel 3, which constitutes the fixed mandrel and is made of metal, is about to collide with the fixed mandrel 2. An electric coil 4 is arranged between the casing and the fixed mandrel 2 and is held in the fixed mandrel 2 by a fastening piece 5.

The lower end of the casing 1 constitutes a skirt 6, the free end of which is fixed to the body 7 and provides a passage 8 for controlling the fluid. The body 7 includes a central nipple 9 on which the movable mandrel 3 is slidably mounted.

The movable mandrel 3 includes a fastening part 5 and a collar 11 on the movable mandrel.
It is pulled toward the main body 7 by the return spring 10 supported opposite to. The movable mandrel 3 has at least one longitudinal slot 12 which constitutes a fluid passage. The movable mandrel 3 itself constitutes a closure device and is intended to impinge on the fixed mandrel 2 to close the fluid passage.

The fluid is carried by a tube (not shown), one end of which is attached to a threaded tip on the fixed mandrel 2 to allow the fluid to penetrate into the valve through a hole 14 extending through the fixed mandrel. it can.

The movable mandrel 3 has a hole 15 and the upper rim of the movable mandrel 3 ends in an annular flange 16 and thus constitutes a closure device intended to abut the underside of the fixed mandrel 2 and close the valve. Acts as the valve seat 20 to form the annular sealing surface 22 in the open position.

The hydraulic valve includes a shock absorber 19 which defines a second annular surface in the form of a flange 18 which is spaced from the flange 16 by an annular throat 17. This flange cooperates with the corresponding fixed mandrel 2 to form an annular cushioning surface 23.
When the annular flange 16 comes into contact with the fixed mandrel 2, the flange 18 is in close proximity to or even in contact with the annular surface 23. The annular throat 17 communicates with the passage 8 through the slot 12, which serves as an outlet tube for liquid.

Therefore, when the valve is closed, the liquid in the tube between the second flange 18 and the surface of the fixed mandrel 2 will be in a radial annular throat portion 17.
To the chamber 21 between the coil 4 and the movable mandrel 3. This is because the flange 16 has the valve seat 2
Before it comes into contact with 0, a braking effect is produced on the movable mandrel 3. The area of the annular cushioning surface 23 is equal to the area of the annular sealing surface 2
It is preferably larger than the area of 2. by this,
A very good braking effect occurs on the movable mandrel of the valve. In principle, in the closed position of the valve, the valve is configured such that there is a few hundredths of a millimeter gap between the flange 18 and the surface 23 while the flange 16 is in contact with the fixed mandrel 2. After some usage, repeated closings of the valve cause bumping of the flange 16 and its supporting surface, so that the clearance between the flange 18 and the annular surface 23 disappears.

It can be seen that in the fully open position of the valve, the entire outer surface of the movable mandrel 3 is surrounded by the fluid at a clearly constant pressure. Therefore, changing the position of the movable mandrel 3 formed by the exciting current in the coil 4 and the restoring force of the spring 10 probably does not receive liquid pressure. In order to be able to compensate for the hydraulic pressure acting on the closure device, if the hole 15 in the movable mandrel 3 extends to the upper end of this mandrel 3 without a change in diameter,
The diameter of the nipple 9 must be at least equal to the inner diameter of the valve seat.

In the embodiment described with reference to FIG. 1, the valve is in the open position with no excitation current. FIG. 2 shows a valve that is closed in the absence of an exciting current and opens based on the effect of the exciting current.

In FIG. 2, elements corresponding to the elements shown in FIG.
Have the same reference numbers. Therefore, the cylindrical casing 1 having the coil 4 installed therein is clamped to the inner cylindrical portion 2 by the nut 24. The base body 25 is screwed onto the inner cylindrical part 2 and has an intake pipe section 6 and an outlet pipe 27. The movable mandrel 3 has at least one longitudinal slot 12
And is pulled by the spring 10 towards the closed position.
The base body 25 has a flat surface 28 arranged opposite the movable mandrel 3 and a central portion 29 projects and cooperates with a rim 30 of the intake tube 26 to form an annular sealing surface 22. The annular sealing surface 22 includes a groove 17 and an annular flange 18.
The annular cushioning surface 23 is constituted by the portions of the flat surfaces 28 which are surrounded by and are arranged opposite to each other. The groove 17 also communicates with the outlet pipe 27 through the vertical slot 12.

The variants shown in FIGS. 3 to 6 differ in the arrangement of the communication between the annular surface and the grooves and their outlet tubes. Third
In the figure, the movable mandrel 3 has a protruding lateral portion 31,
The annular cushioning surface 23 is separated from the annular sealing surface 22 by a groove 17. Radial slots 32, of which only one is shown, are provided in the protruding portion 31 and are
Serves as a passage for the liquid trapped in 7.

In the modification shown in FIG. 4, the groove 17 is formed in the base body 2
5, the passage connecting the groove 17 with the outlet pipe consists of at least one conduit 33 passing through a part of the movable mandrel facing the groove 17.

On the other hand, in FIG. 5, the groove 17 is arranged in the outer peripheral part of the movable mandrel 3 and the passage is in the form of a radial slot 34 in the base body 25.

Finally, in the variant shown in FIG. 6, the groove 17 and the conduit connecting the groove 17 and the outlet pipe are
It is located inside.

[Brief description of drawings]

FIG. 1 is an axial sectional view showing a first embodiment of the present invention. FIG. 2 is an axial sectional view of a second embodiment of the present invention. 3 to 6 are axial detailed sectional views showing the features of the special modification. 7 ... Main body 2 ... Fixed mandrel 3 ... Metallic ferromagnetic movable mandrel 20 ... Valve seat 19 ... Shock absorber 27 ... Exit pipe 23 ... Annular shock absorbing surface 18 ... Second annular surface (flange)

Claims (7)

[Claims] 1. A hydraulic solenoid including a main body, a fixed mandrel, and a metallic ferromagnetic movable mandrel adapted to be displaced against the action of the restoring force of a spring through a magnetic field generated by an exciting current. A valve, wherein the ferromagnetic movable mandrel constitutes an occlusion device which cooperates with a valve seat to control fluid through the valve, the occlusion device forming an annular sealing surface with the valve seat in a closed position of the valve. A hydraulic solenoid valve for forming, the hydraulic solenoid valve including a shock absorber comprising at least one second annular surface separated radially outward from the annular seal surface by an annular throat, the second annular surface Is
An annular dampening surface is formed in cooperation with the oppositely arranged counterparts, the annular dampening surface being positioned near the mating portion when the closure device is in contact with the valve seat and the annular seal surface. Said annular throat between the annular cushioning surfaces is in communication with the valve outlet tube through at least one passage,
Hydraulic solenoid valve characterized by. 2. The hydraulic solenoid valve according to claim 1, wherein the area of the annular cushion surface is larger than the area of the annular seal surface. 3. A space between the annular surfaces comprises a groove in the movable mandrel.
The hydraulic solenoid valve according to item. 4. A hydraulic solenoid valve according to claim 1, wherein the space between the annular surfaces comprises a groove in the valve seat. 5. A passage between the groove and the outlet pipe is in the movable mandrel, as claimed in claim 3 or 4.
The hydraulic solenoid valve according to item. 6. A hydraulic solenoid valve according to claim 3 or 4, wherein the passage between the groove and the outlet pipe is in the valve seat. 7. A hydraulic solenoid valve according to claim 3, wherein the movable mandrel has at least one longitudinal slot communicating with the groove.