JPH01320384A - Electromagnetic drive device for fluid control - Google Patents

Abstract

PURPOSE:To prevent the falling of the filter provided in the following communicating hole by constituting the communicating hole executing the flow-in and out of an oil by the movement of a plunger in the radial direction by a 1st communicating hole and the 2nd communicating hole orthogonal therewith. CONSTITUTION:A 1st communicating hole 19 is pierced at the midway part of a center hole 11 so as to vertically communicating therewith. A 2nd communicating hole 20 is communicated with the 1st communicating hole 19 and pierced in parallel to the center hole 11. A filter 21 is fitted to the 1st communicating hole 19 from the outer periphery of a fitting body 3. Consequently the thrust power of a fluid is not acted on the filter 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic sleeper for a fluid control member such as a hydraulic control valve.

[Prior Art] FIG. 3 shows a general configuration of an electromagnetic isolator for this type of hydraulic control valve.

In the figure, l is partially connected to the first inner yoke 2.
A yoke body 3 constituting the yoke body 3 is a mounting body that partially constitutes the second inner yoke 4, and both yoke bodies 1 and 3 are connected by a non-magnetic sleeve 5. In a substantially cylindrical cavity 6 formed by the yoke body 1 and the mounting body 3, a cylindrical plunger is disposed so as to be movable in the left-right direction in the figure, and a rod 8 integrated with the plunger 7 is disposed. , bearing 9
10 so as to be slidable in the thrust direction. A portion of the rod 8 protrudes to the outside, and its protruding tip 8a urges a valve (not shown) serving as an external load, and a valve spring (also not shown) provides the rightward biasing behavior as shown in the drawing. has been done. Reference numeral 11 denotes a center hole into which the rod 8 is loosely inserted, which is bored in the mounting body 3 along its thrust direction and is isolated from the cavity 6 by the bearing 10.

12 is a coil bobbin fitted onto the sleeve 5;
13 is a coil wound around the coil bobbin 12; 14;
is a case body serving as an outer yoke that is assembled on the coil 13 and the collar portion 15 of the yoke body 1, and is welded and
It is mechanically coupled to the yoke body 1 and the mounting body 3 by means such as screwing or caulking. Reference numeral 30 denotes a communication hole parallel to the center hole 11, which is bored in the mounting body 3, and communicates the cavity 6 with a hydraulic circuit (not shown).5Therefore, the cavity 6 is filled with oil. ing. In addition, 16 is a rear oil chamber provided in the yoke body 1.

It communicates with the cavity 6 through a communication hole 17 . Also, 1
8 is an O-ring for sealing.

In the above configuration, when the coil 13 is energized, the branjawa moves to the left in the figure due to magnetic force.

The tip of the rod 8 presses the external load to do work, and when the current to the coil 13 is cut off, the branjawa returns to the right by the spring of the external load. When the plunger 7 moves from side to side in this way, the oil filled in the cavity 6 is transferred to the communication hole 3.
If the external oil is contaminated with metal powder, etc., the foreign matter will accumulate inside the electromagnetic drive unit due to the magnetic force when the oil flows in and out, and the movement of the Branjawa will be interrupted. This may cause the electromagnetic drive device to malfunction.

Or it may cause sticking.

Therefore, conventionally, as shown in FIG. 4, a filter 31 is installed in the communication hole 3o, and the filter 31 removes foreign substances contained in the oil and prevents metal powder etc. from entering the cavity 6. was taken into consideration.

[Problems to be Solved by the Invention] By the way, in the configuration shown in FIG. 4 described above, the filter 3
1, a force in the thrust direction acts on the filter 31 due to the pressure loss of the oil that is the fluid passing through the filter 1. Therefore, it is dangerous to use the filter 31 without a means to prevent it from falling off, as there is a high possibility that the filter 31 will fall off. .

Therefore, if the filter 31 is made of paper or fine wire mesh, for example, the rigidity of the filter 31 is insufficient to fix the filter 31 only by the frictional force between the filter 31 and the inner surface of the communication hole 30. If the filter 31 is inserted irregularly and forcibly, the filter 31 will be deformed, so the filter 31 is loosely fitted into the communication hole 30, and the filter 31 is fixed with a means to prevent removal, such as a retaining ring 32, as shown in the fourth figure. Ta. However, the work of attaching the retaining ring 32 is complicated and also results in an increase in the number of parts.

Further, even when the filter 31 is made of a sintered alloy with high rigidity, if the filter 31 is press-fitted into the communication hole 30 with a large interference so that it cannot fall off, the metal particles of the filter 31 itself will peel off. The inner body of the filter 31 becomes a source of foreign matter.

On the other hand, it is conceivable to fix the filter 31 with an adhesive, but the adhesive enters the filter 31 through a capillary TIA phenomenon, causing the filter 31 to become clogged. It is also possible to use an adhesive with a very high viscosity, but this would result in extremely poor workability and poor adhesion between the filter 31 and the inner surface of the communication hole 30.

In this way, the conventional method of fixing the filter 31 is assembling work 5.
There was a problem in at least one of the following points, such as the number of parts and a decrease in filter function.

Therefore, the technical problem to be solved by the present invention is to solve the above-mentioned problems of the prior art. An object of the present invention is to provide an electromagnetic dynamic device for fluid control, which has a structure that allows it to perform its intended function.

[Means for Solving the Problems] The above-mentioned objects of the present invention are to provide a plunger that can move forward and backward in a cavity filled with fluid in an electromagnetic device, a center hole provided in the thrust direction of the electromagnetic device, and a center hole provided in the thrust direction of the electromagnetic device. a rod that is loosely inserted into the hole and is integrated with the plunger and is capable of driving an external load;
In a fluid/control electromagnetic drive device comprising a bearing means for the rod provided in the center hole and sealing between the center hole and the cavity, a radial shaft communicating with the center hole; a second communication hole parallel to the center hole that communicates with the first communication hole and the cavity; This is achieved by providing a filter with a filter attached.

[Function] As described above, in the present invention, a filter is inserted into the first communication hole in the radial direction, and the position of the filter is restricted in the direction toward the center hole by, for example, a stepped portion of the first communication hole. In addition, the position of the filter in the direction toward the outer periphery is restricted by, for example, a coil bobbin or sleeve required for this type of electromagnetic drive device, so that the filter is extremely easy to assemble, yet the filter is securely secured so that it cannot be removed. Retained.

Furthermore, there is no risk that the filter will be deformed and its function will be impaired.

[Example] The present invention will be described below with reference to illustrated examples. 1st
The figure is a cross-sectional side view of the electromagnetic drive device according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional side view of the electromagnetic drive device according to the second embodiment of the present invention. The same reference numerals are given to the same members and parts as those in the conventional structure, and the explanation thereof will be omitted to avoid duplication.

In FIG. 1, reference numeral 19 denotes a first communication hole provided in the radial direction of the mounting body 3. The first communication hole 19 extends from the outer periphery of the mounting body 3 to the center so as to communicate perpendicularly to the center hole 11 at a midway point. It is penetrated and drilled toward the hole 11. 20
is a second communication hole that communicates the cavity 6 of the electromagnetic drive device described above with the first communication hole 19; The holes are bored in parallel and do not penetrate to the outside. The cavity 6 has a second communication hole 20. First communication hole 19
．． It communicates with a hydraulic circuit (not shown) through the center hole 11, and the oil in the cavity 6 is changed as the plunger 7 moves forward and backward.
Outflow and inflow are repeated through the second communication hole 20, the first communication hole 19, and the center hole 11.

Reference numeral 21 denotes a filter, which is loosely fitted into the first communication hole 19 from the outer peripheral side of the mounting body 3, and whose tip is at least connected to the second communication hole 19.
It has reached a position where it covers the communication hole 20 of. Reference numeral 21a denotes a large-diameter portion of the filter 21, and when the large-diameter portion 21a comes into contact with the stepped portion 22 of the first communication hole 19, the filter 21
movement in the direction toward the center hole 11 is restricted. Further, the top surface of the large diameter portion 21a of the filter 21 is provided with a coil bobbin 23 that connects the mounting body 3 and the yoke body 1.
Movement in the outer circumferential direction is restricted, and in this way, the filter 21 is positioned and inserted into the first communication hole 19 with its upper and lower ends irremovably. There is.

That is, in this embodiment, the yoke body 1 is.

The cylindrical body IA and the lid body IB are integrated in a post-process, and the cylindrical body IA and the mounting body 3 in which the filter 21 is inserted into the first communication hole 19 are formed by injection molding. After being integrated with the coil bobbin 23, the plunger 7 and the lid IB are assembled one after another. Note that the welding resin used for injection molding has a high viscosity, and there is no possibility that the portion of the filter 23 that performs the filter function will become clogged.

In this embodiment with the above configuration, the filter 21 can be assembled very easily, and the filter 21 can be reliably positioned without requiring a separate means for preventing the filter 21 from being removed.
The filter 21 can exhibit the desired performance without being deformed or clogged with adhesive or the like.

In a second embodiment of the invention shown in FIG.

The filter 24 loosely fitted into the first communication hole 19 has one end thereof positionally regulated by the stepped portion 25 of the first communication hole 19 and the other end thereof positionally regulated by the sleeve 5. . In this case as well, after inserting the filter 24 into the first communication hole 19, other parts may be assembled one after another, and the same effect as in the first embodiment can be achieved.

Note that the stepped portion of the first communicating hole 19 in the present invention refers to, for example, a protruding step portion in the radial direction, or a stepped portion of the first communicating hole 19 that gradually decreases in diameter toward the center, for example, other than the illustrated embodiment. It goes without saying that various modifications may be made without departing from the spirit of the present invention.

[Effects of the Invention] As described above, according to the present invention, it is extremely easy to assemble the filter, the filter can be reliably positioned without the need for a separate means for preventing removal, and the filter is removed during the assembling process. It is possible to provide an electromagnetic drive device for fluid control that has a filter that can perform the intended filter function without causing deformation or clogging, and is of great value.

[Brief explanation of the drawing]

1 is a cross-sectional side view of an electromagnetic drive device for fluid control according to a first embodiment of the present invention, FIG. 2 is a cross-sectional side view of an electromagnetic drive device for fluid control according to a second embodiment of the present invention, and FIG. The figure shows a conventional general electromagnetic drive device for fluid control 1...Yoke body,
IA...Cylindrical body, IB...Lid body, 2.
...First inner yoke, 3...Mounting body, 4...Second inner yoke, 5...
Sleeve, 6...Cavity, 7...Plunger, 8...Rod, 8a...Protruding tip, 9, 10...Bearing, 11... Center hole, 12... Coil bobbin, 13...
Coil, 14...Case body (outer yoke)
, 16...Rear oil chamber, 17...Communication hole, 18...O ring. 19...First communication hole, 20...Second
Communication hole, 21... Filter, 21a...
... Large diameter part, 22 ... Stepped part, 23 ...
Coil bobbin, 24...filter. 25...Dan section. Figure 1

Claims (2)

[Claims] (1) A plunger that can move forward and backward in a fluid-filled cavity inside the electromagnetic device, a center hole provided in the thrust direction of the electromagnetic device, and the plunger that is loosely inserted into the center hole and can drive an external load. In the electromagnetic drive device for fluid control, the electromagnetic drive device for fluid control includes a rod integral with the rod, and a bearing means for the rod provided in the center hole and sealing between the center hole and the cavity. a first communication hole in the radial direction that communicates with the hole; a second communication hole parallel to the center hole that communicates with the first communication hole and the cavity;
An electromagnetic drive device for fluid control, comprising a filter whose upper and lower sides are irremovably positioned and inserted into a communication hole. (2) In claim (1), the filter is positioned in a direction toward the center hole by a stepped portion of the first communication hole, and in a direction away from the center hole by a coil bobbin or a sleeve. An electromagnetic drive device for fluid control characterized by position regulation.