JPH0442615Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Purpose of the invention (1) Industrial application field This invention relates to electromagnetic operating devices such as solenoid valves, and more specifically, to prevent residual magnetism in the electromagnetic operating part of the electromagnetic operating device. Regarding the mounting structure of the magnetic killer.

(2) Prior Art In electromagnetic actuators, residual magnetism is generated in the fixed core or the movable core when power is cut off, and as a result, the movable core may not return instantaneously to the closing direction due to the biasing force of the return spring.

In order to prevent this, a magnetic killer made of a non-magnetic material is provided on one of the mutually opposing surfaces of the fixed core and the movable core.

That is, in Utility Model Application Publication No. 55-46831, a magnetic killer (spacer) is provided on the fixed core side, and in Utility Model Application Publication No. 56-143675, a magnetic killer (metal shim) is provided on the movable core (valve body) side. ) is provided.

However, all of these magnetic killers are designed to be attached using adhesives, brazing, or the like, which not only requires skill and effort in the bonding work, but also poses problems in attachment accuracy.

(3) Problems to be solved by the invention The present invention has been made to solve the above-mentioned problems, and it is an electromagnetic actuator of this type that can accurately and easily install a magnetic killer. The technical problem (object) is to provide a mounting structure for the killer.

B. Structure of the invention (1) Means for solving the problem According to the invention, a fixed core and a movable core are disposed in series with each other in the axial direction, and the fixed core and the movable core are mutually connected. A plate-shaped magnetic killer made of a non-magnetic material is provided on one of the surfaces facing the core, and a spring housing recess in which one end of the return spring is accommodated is provided on one surface of the opposing core. In an electromagnetic actuating device in which the other end of the spring is fitted onto a cylindrical projection provided on the surface of the other core, a reduced diameter portion having a required length is provided at the root of the cylindrical projection of the core. The magnetic killer has an annular shape with a circular hole in the center thereof, the outer diameter thereof is maintained at a size that at least substantially blocks residual magnetism, and the thickness thereof is equal to the diameter of the reduced diameter portion of the protrusion of the core. and the diameter of the circular hole is substantially equal to or slightly smaller than the maximum diameter of the projection, and slightly larger than the diameter of the reduced diameter portion of the projection. It is characterized by being

In this configuration, the outer diameter of the magnetic killer is ``a size that at least substantially blocks residual magnetism.''
This is the configuration adopted by ordinary magnetic killers, and means that it is large enough to block most of the residual magnetism.

(2) Function When assembling the magnetic killer, only one predetermined piece of the magnetic killer is fitted into the reduced diameter portion of the protrusion of the fixed core. After the magnetic killer is fitted into the protrusion, it is loosely fitted, so there is no deformation of the magnetic killer.

Furthermore, since the magnetic killer is held under the pressure of the return spring, it does not move erratically even when subjected to vibrations.

(3) Embodiment An embodiment of the electromagnetic actuator of the present invention will be described based on the drawings.

(Configuration of Embodiment) FIG. 1 shows a fluid control solenoid valve V according to one embodiment, which is applied to control the flow rate of an air-fuel mixture in a low-speed range fuel system of a carburetor of an internal combustion engine.

This electromagnetic valve V includes a fluid control section 1 that controls the flow of the air-fuel mixture by opening and closing a valve body, and an electromagnetic actuating section 2 that opens and closes the valve body of the fluid control section 1 by electromagnetic force.

Hereinafter, the configurations of the fluid control section 1 and the electromagnetic actuation section 2 will be sequentially explained. During this explanation, please note that the upper and lower parts of the
The front and rear positions are relative to the drawing, and are not specific to the upper, lower, front, or rear positions.

The fluid control unit 1 includes a valve casing 5 having a valve hole.
and a valve body 6 which is housed within the valve casing 5 and opens and closes the valve hole.

More specifically, the valve casing 5 has a substantially cylindrical shape, has a valve hole 7 and openings 8, 9 in the front part, and has a spigot part 5a in the rear part, which is fitted and fixed to a housing to be described later. . The opening 8 has an opening area of a large cross section, and the opening 9 has an opening area of a small cross section. Then, the air-fuel mixture flows in through the openings 8 and 9 and is discharged through the valve hole 7. The valve body 6 has a substantially round rod shape, its outer periphery is supported by the inner circumferential surface of the valve casing 5, and the valve body 6 is inserted into the valve casing 5 so as to be movable in its axial direction. The valve head 10 of the valve body 6 is seated on the valve seat 7a of the valve hole 7, and opens and closes the valve hole 7 by moving toward and away from the valve seat 7a. A rear base portion 11 of the valve body 6 faces a fixed core, which will be described later, and forms a movable core.

The electromagnetic actuator 2 includes a fixed core 15 disposed longitudinally in the center thereof, a bobbin 16 made of synthetic resin disposed in a tight fit around the outer periphery of the fixed core 15, and an electromagnetic actuator wound around the bobbin 16. Coil 17, bobbin 1
6, a housing 19 that encloses the bobbin 16, coil 17, and yoke 18 and extends forward and backward, and between the fixed core 15 and the valve body 6. It further includes a magnetic killer 21, a ground terminal 23, and a power supply terminal 24. The gap between the housing 19 and the electromagnetic coil 17 is filled with resin 25.

More specifically, the fixed core 15 is made of a long cylindrical member made of a magnetic material, and the front end 15a thereof has a small cylindrical protrusion 27 protruding from the center, and the rear end has a caulking protrusion 28. is installed protrudingly. The return spring 20 and the magnetic killer 21 are assembled to the small projection 27, and the yoke 18 and the ground terminal 23 are assembled to the caulking projection 28.

The bobbin 16 has a circular hole 16 that passes through the shaft center inside the bobbin 16.
The fixed core 15 is tightly fitted into this circular hole 16a. The front part of the bobbin 16 extends beyond the front end surface 15a of the fixed core 15 with a flange 16b,
The base portion 11 of the valve body 6 is loosely inserted into the circular hole 16a in the front portion while being allowed to move and facing the front end surface 15a of the fixed core 15. To be more specific, a circular hole 3 is formed in the base 11 of the valve body 6 from the center of the rear end surface 11a.
One end of the coiled return spring 20 is seated at the bottom of the circular hole 30, and the other end is fitted into the small protrusion 27 of the fixed core 15. Magnetic killer 2 in contact
1 is seated on top. As a result, the valve body 6 is always subjected to a biasing force in the forward direction. Further, the annular rear end surface 11a of the valve body base 11 is connected to the front end surface 1 of the fixed core 15.
They face each other via a magnetic killer 21 fixed to 5a.

The rear part of the bobbin 16 is formed thickly, and the ground terminal 23 is embedded in this part, and the plug terminal 2
A recessed portion 16c is formed to receive the 4. 31
is an airtight O-ring.

The magnetic coil 17 wound around the bobbin 16 has its positive pole side electrically connected to a power supply terminal 24 received in the concave portion 16c of the bobbin 16, and its negative pole side electrically connected to a ground terminal 23 embedded in the bobbin 16. Ru.

The yoke 18 has a predetermined thickness and is substantially disk-shaped, and has an insertion hole 33 in the center through which the caulking projection 28 of the fixed core 15 is inserted.

The housing 19 has a cylindrical shape and encloses the assembly consisting of the bobbin 16, coil 17, and yoke 18, and when the assembly is assembled into the housing 19, the front end of the bobbin 16 and the back surface of the housing 19 Annular seal plate 4
1 is interposed.

The front extending portion of the housing 19 has a reduced diameter, and the base portion 11 of the valve body 6 is fitted into the inner hole 19a with a predetermined gap therebetween. In addition, the front end 19
b is formed in the socket portion, and the socket portion 19b
The spigot portion 5a of the valve casing 5 is firmly inserted and fixed.

The rear extending portion of the housing 19 is made thinner than the main body portion of the housing, and is caulked inwardly via the yoke 18.

The filler resin 25 is filled after the assembly is inserted into the housing 19 at a predetermined position and the rear extension of the housing 19 is caulked inward.

In this configuration, this embodiment is characterized by the mounting structure of the magnetic killer 21.

The detailed structure of this part will be explained with reference to FIGS. 2 to 4.

The protrusion 27 of the fixed core 15 has a cylindrical shape with a substantially equal cross section, and is formed into a reduced diameter portion 27a that is slightly reduced in diameter over a predetermined length a at its base.

The magnetic killer 21 is made of a non-magnetic material and forms a ring body having a circular hole or punched portion 21a inside.
In this embodiment, the outer diameter of the magnetic killer 21, in other words, the diameter D of the main body 21b is the outer diameter of the end surface 15a of the fixed core 15, in other words, the inner hole 1 of the bobbin 16
The diameter is slightly smaller than that of 6a.

In addition, in keeping with the spirit of the present invention, the outer diameter of the magnetic killer 21 must be large enough to substantially block residual magnetism, and at the same time should not cause any inconvenience in handling during assembly. Good to have.

In addition, the inner diameter of the punched portion 21a, in other words, the diameter d of the punched portion 21a is slightly smaller than the maximum diameter b of the projection 27 in this embodiment, and the reduced diameter portion 27
It is made slightly larger than the diameter c of a. Alternatively, the inner diameter d may be slightly larger than the maximum diameter b of the protrusion 27.

The thickness t of the magnetic killer 21 is
It occupies the majority of the length of 7a, preferably about 2/3.

The solenoid valve V of this embodiment has the above-mentioned configuration. Among these components, the fixed core 15, yoke 18, housing 19, and valve body 6 are made of magnetic materials, and when the solenoid coil 17 is excited, , these form a magnetic path.

Note that due to the presence of the flange 16b at the front of the bobbin 16, the magnetic path passes through the valve body 6 without being short-circuited from the housing 19 to the fixed core 15. Therefore, only the base 11 of the valve body 6 needs to be made of a magnetic material, and the rest can be made of another material and fixed to the base 11.

Further, the ground terminal 23 is electrically connected to the housing 19 via the yoke 18, and is grounded to the main body.

(Operation of the embodiment) Next, the operation of the fluid control solenoid valve V of this embodiment will be explained.

When no current is supplied to the electromagnetic coil 17 and the electromagnetic coil 17 is in a demagnetized state, the valve body 6 is in the position shown in FIG. 1 (demagnetized position) due to the spring bias of the return spring 20, and the valve body 6 valve body head 1
0 is seated on the valve seat 7a of the valve hole 7. Therefore, the flow from the opening 8 to the valve hole 7 is blocked, and only the opening 9 is in communication with the valve hole 7, and a small amount of the air-fuel mixture is discharged to the valve hole 7 through the opening 9 with a small cross section. Ru.

When current is supplied to the electromagnetic coil 17, the electromagnetic coil 17 becomes excited, and the magnetic flux from the electromagnetic coil 17 is applied to the fixed core 15, the yoke 18, and the housing 1.
A closed loop magnetic path is formed that returns to the fixed core 15 via the valve body 9 and the valve body 6, and a magnetic attraction force is generated between the stationary core 15 and the valve body 6 according to the value of the current.

Along with this, the valve body 6 moves in the axial direction against the biasing force of the return spring 20, and the valve body head 10 of the valve body 6 moves.
is separated from the valve seat 7a of the valve hole 7, so the opening 8 and the valve hole 7 communicate with each other. Therefore, a large amount of the air-fuel mixture is discharged into the valve hole 7 through the opening 8 having a large cross section.

When the current to the electromagnetic coil 17 is stopped, the attractive force of the valve body 6 disappears, and the valve body 6 is pushed back toward the valve seat 7a by the biasing force of the return spring 20. At this time, since the residual magnetism is reduced as much as possible by the magnetic killer 21, the valve body 6 immediately returns to its original position, that is, the demagnetized position, by the biasing force of the return spring 20, resulting in so-called highly responsive operability. Demonstrate.

In the magnetic killer 21 in this embodiment, the annular main body portion 21a covers the entire area facing the movable core, so that most of the residual magnetism is blocked.

Furthermore, since the electromagnetic valve V of this embodiment adopts the above-described mounting structure for the magnetic killer 21, the mounting work is performed as follows.

First, the magnetic killer 2 is attached to the protrusion 27 of the fixed core 15.
1 is inserted. At this time, since the inner diameter of the magnetic killer 21 is slightly smaller than the maximum diameter of the protrusion 27, the main body portion 21b of the magnetic killer 21 rides over the protrusion 27 due to its elasticity and is fitted into the reduced diameter portion 27a. When the magnetic killer 21 reaches the reduced diameter portion 27a, it returns to its original flat state. Thereafter, the magnetic killer 21 engages with the boundary between the reduced diameter portion 27a and the enlarged portion of the protrusion 27, that is, the stepped portion, and does not easily come off.

In addition, in an embodiment in which the inner diameter of the magnetic killer 21 is made slightly larger than the maximum diameter of the protrusion 27, there is no elastic deformation, but after it is fitted into the reduced diameter part 27a, it engages with the step part and easily deforms. The same goes for not coming off. In this case, the protrusion 27 of the magnetic killer 21
Since the tip of the protrusion 27 is tapered, the tip of the projection 27 is guided by the taper and can be easily inserted.

Next, the return spring 20 is fitted into the protrusion 27,
The end thereof is brought into contact with the magnetic killer 21. As a result, the magnetic killer 21 is pressed elastically by the return spring 20, and does not move erratically even when subjected to impact.

The present invention is not limited to the above-mentioned embodiments, and various design changes can be made within the scope of the basic technical idea of the present invention. That is, the following aspects are included within the technical scope of the present invention.

The portion of the magnetic killer 21 facing the circular hole 21a having a diameter smaller than the diameter of the protrusion 27 is made thin as shown by the broken line in FIG. According to this aspect, the flexibility of the portion is increased, and the thickness of the magnetic killer 21 can be increased.

C. Effect of the invention Since the electromagnetic actuating device of the invention adopts the above-described configuration, it is possible to prevent the incorrect assembly of two or more magnetic killers during assembly, and after the magnetic killer is assembled, it is easily engaged with the reduced diameter part. Therefore, the assembly work can be carried out easily and efficiently. In addition, since the magnetic killer is pressed and held by the return spring, there is no accidental movement of the magnetic killer, and the electromagnetic actuating device continues to function well.

[Brief explanation of the drawing]

The drawings show an embodiment of the electromagnetic actuation device of the present invention,
Fig. 1 is a longitudinal sectional view showing the overall structure of a solenoid valve according to one embodiment, Fig. 2 is a sectional view of its main parts, Fig. 3 is a schematic sectional view showing its dimensional relationship, and Fig. 4 is a magnetic filter. FIG. 6... Valve body (movable core), 15... Fixed core,
20... Return spring, 21... Magnetic killer, 30...
...Spring housing recess.

Claims (1)

[Claims for Utility Model Registration] A fixed core and a movable core are disposed in series with each other in the axial direction, and one of the mutually opposing surfaces of the fixed core and the movable core is made of a non-magnetic material. A plate-shaped magnetic killer is provided, one surface of the opposing core is provided with a spring accommodating recess in which one end of the return spring is accommodated, and the other end of the return spring is provided on the surface of the other core. In the electromagnetic actuating device that is fitted onto a cylindrical projection, a reduced diameter portion having a predetermined length is formed at the root of the cylindrical projection of the core, and the magnetic killer has a circular hole at the center thereof. It has an annular shape, its outer diameter is maintained at a size that at least substantially blocks residual magnetism, and its thickness accounts for the majority of the length of the reduced diameter portion of the protrusion of the core, and the thickness of the circular hole An electromagnetic actuating device characterized in that the diameter is substantially equal to or slightly smaller than the maximum diameter of the projection, and slightly larger than the diameter of the reduced diameter portion of the projection.