JPH0483312A - Electromagnet device - Google Patents

Abstract

PURPOSE:To enable differential sound when a movable core collides to be reduced and prevent suction force in suctioned state from being restricted by allowing a vibration energy absorbing body which consists of a particle of a magnetic body or a magnetic fluid to be incorporated into at least either of a fixed core or a movable core. CONSTITUTION:A magnetic circuit M is formed by a yoke 1, a fixed core 2, a movable core 3, and a variable magnetic void 4 and then a coil 5 is wound around a coil frame 6. The movable core 3 is in cylindrical shape, a hollow base is formed by a cylindrical body with bottom 3e and a covering body 3f which blockes an opening, and a particle 3h of the magnetic body is incorporated. In the fixed core 2, a particle 2h of a magnetic body is incorporated into a hollow space which is formed by a cylindrical body 2e with bottom and a cover body 2f. When the coil 5 is excited, magnetic flux flow, the movable core 3 is suctioned to the fixed core 2, and one end face 3a hits against the tip surface 2a. In this case, the particles 2h and 3h rubs each other and operate as an absorber of vibration energy, thus enabling working sound to be reduced. Also, the movable core is positively suctioned in suction state, thus preventing suction force from being reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnet device used as an actuator for industrial equipment or consumer equipment.

[Conventional technology]

Among this type of electromagnetic device, the plunger type is the 6th type.
The configuration shown in the figure is common. That is, the cross-sectional angle C
A letter-shaped yoke 1, a fixed core 2 fixed to the yoke 1, a movable core 3 whose one end surface 3a faces the tip end surface 2a of the fixed core 2, and a variable magnetic gap 4 interposed between both cores 2 and 3.
The main components are a magnetic circuit H formed by the magnetic circuit H, and a coil 5 wound around a coil frame 6 to flow magnetic flux through the magnetic circuit i. The other side of the movable core 3 is connected to a driven member (not shown), and is biased in a direction away from the fixed core 2 by a spring member (not shown).

When the coil 5 is in a non-excited state, the movable core 3 is farthest away from the fixed core 2, and the variable magnetic gap 4 is at its maximum.
When the coil 5 is energized, it is attracted to the fixed iron core 2, and one end surface 3'a collides with its tip surface 2a. Further, if the coil 5 is de-energized in this state, some of the coils may be released from the fixed iron core 2 and separate, and then collide with the driven member. Such a collision generates operating noise of the electromagnetic device.

Incidentally, in recent years, there has been an increasing demand for reducing the above-mentioned operating noise. As a plunger type electromagnet device that meets such demands, one disclosed in Japanese Utility Model Application Laid-Open No. 51-8453 has been proposed. As shown in FIGS. 7 and 8, this device is provided with a buffer member 3C made of an elastic material on one end surface 3a of the movable iron core 3. Therefore, the vibration (impact) energy when the movable iron core 3 collides with the fixed iron core 2 is absorbed and relaxed, and the operating noise can be reduced.

Moreover, as shown in FIG. 9 and FIG.
A buffer seat 3d made of a flexible magnetic material is fixed to one end surface 3a. A flexible magnetic material is made by mixing and molding magnetic powder into a flexible material such as rubber or plastic.

Like the previous one, this one can also reduce operating noise.

[Problem to be solved by the invention]

Although the two conventional examples described above can reduce operating noise by absorbing and relaxing the vibration (impact) energy at the time of a collision of the movable core, they have the following drawbacks. That is, in the former case, the opposing area of the movable iron core decreases due to the provision of the buffer member, and the total suction force decreases, and the suction force in the suction state becomes relatively small due to the spring force of the buffer member. In the latter case, in the attracted state, the non-magnetic material portion of the buffer seat becomes substantially similar to an air gap, increasing magnetic resistance, and as a result, the attractive force in the attracted state also becomes relatively small. It is.

The present invention has been made in view of the above circumstances, and its purpose is to reduce the operating noise of the movable iron core when it collides with the movable iron core, and to suppress the reduction in the attractive force of the movable iron core in the suction state. We are in the process of providing equipment.

(Means for Solving the Problems) In order to solve the problems, the electromagnet device of the present invention has the following features:
It has a magnetic circuit formed by a yoke, a fixed core, a movable core, a variable magnetic gap between the fixed core and the movable core, and a coil for flowing magnetic flux through this magnetic circuit, and by controlling the excitation of the coil. In an electromagnetic device in which a movable core is attracted to and released from a fixed core, at least one of the fixed core and the movable core has a built-in vibration energy absorber.

This vibration energy absorber can be made of magnetic particles,
Preferably, it is a magnetic fluid.

[Effect]

According to this configuration, when the movable core collides with the fixed core, the vibration energy absorber absorbs and alleviates the vibration (impact energy) to reduce operating noise, and in the suction state, the movable core reliably collides with the fixed core. It is possible to prevent the suction force from decreasing due to adsorption.

〔Example〕

Hereinafter, a first embodiment of the present invention will be described based on FIGS. 1 to 3. Note that the same reference numerals are given to substantially the same members as those in the conventional example described above.

Reference numeral 1 denotes a yoke, which has a C-shaped cross section with a base piece 1a, an opposing piece 1b, lb, and tip pieces lc, lc. Tip piece 1c
+1c may be made into a single flat plate or may be separated into pieces with a predetermined gap interposed therebetween, but a bearing bush ld for guiding a movable iron core, which will be described later, is attached thereto. Further, a caulking hole 1e is provided approximately at the center of the base piece 1a and coaxially with the bearing bush 1d.

In the specific manufacture of this yoke 1, the base piece 1a and the opposing pieces 1b, 1b are integrally formed, and the separately formed tip pieces 1c, lc are joined to this by welding or the like.

Reference numeral 2 denotes a fixed iron core, which has a cylindrical shape that is considerably shorter than the opposing piece 1b of the yoke 1, and whose base end 2b is connected to the caulking hole 1e of the yoke 1.
It is inserted and fixed. The tip surface 2a becomes a suction contact surface (suction surface) of a movable iron core, which will be described later. Important parts of this fixed iron core 2 will be described later.

Reference numeral 3 denotes a movable core, which has a cylindrical shape with an outer diameter slightly smaller than that of the fixed core 2 but is sufficiently longer than the fixed core 2, and the bearing bushing 1 is arranged so that one end surface 3a on the fixed core side faces the tip surface 2a.
guided by d. On the other hand, the end surface 3a side has a slightly tapered shape. The other end 3b is connected to a driven member (not shown). Further, the movable core 3 is normally biased by a spring member (not shown) in a direction away from the fixed core 2 . Important parts of this movable iron core 3 will also be described later.

Reference numeral 4 denotes a variable magnetic gap, which is formed between the tip surface 2a and one end surface 3a of both cores 2 and 3, and is released to a minimum (zero) when the movable core 3 is attracted to the fixed core 2. when it reaches its maximum.

A magnetic circuit H is formed by the above-described yoke 1, fixed core 2, movable core 3, and variable magnetic gap 4.

A coil 5 is wound around a coil frame 6 in order to cause magnetic flux to flow through the magnetic circuit H. The coil frame 6 includes a cylindrical winding trunk 6a and flanges 6b, 6b connected to both ends thereof. The winding trunk portion 6a has an inner diameter approximately equal to the outer diameter of the fixed iron core 2, and an axial length approximately equal to the inner diameter of the base piece 1a and the tip piece 1c of the yoke 1. The outer shape of the collar portions 6b, 6b is slightly smaller than the distance between the opposing pieces 1b, 1b of the yoke 1. The fixed core 2 and the movable core 3 fit into the drum 6a, so that the movable core 3 is also guided by the drum 6a.

Next, important parts of the fixed core 2 and the movable core 3 will be explained. The movable core 3 has a cylindrical shape as a whole, but specifically, as shown in FIG. A hollow space 3g is formed. This hollow space 3g contains particles 3h of a magnetic material such as iron, each having a diameter of about 0.1 to 0.5 mm. This movable iron core 3 stores particles 3h corresponding to about 80% of the volume of the hollow space 3g in a bottomed cylinder 3e, and then closes the opening with a lid 3f by caulking, welding, or the like. Similarly, in the fixed core 2, magnetic particles 2h are housed in a hollow space 2g formed from a bottomed cylinder 2e and a lid 2f.

In such an electromagnet device, when the coil 5 is in a non-excited state, the movable core 3 is farthest away from the fixed core 2 and a variable magnetic gap 4 is formed.
is the maximum. When the coil 5 is excited in this state, the magnetic flux Φ flows from the fixed iron core 2 → the yoke 1 → the movable iron core 3 → the variable magnetic gap 4 → the fixed iron core 2, and therefore the movable iron core 3 is attracted to the fixed iron core 2 and its tip surface 2a One end surface 3a collides with the other end surface 3a. During this collision, particles 2h and 3h contained in both iron cores 2 and 3 rub against each other, and as a result, vibration (impact) energy is converted into thermal energy. That is, particles 2h
, 3h act as vibration energy absorbers. When the applicant conducted experiments, it was confirmed that the operating noise was reduced by about 80% compared to the general one shown in FIG. Furthermore, when the coil 5 is de-energized in this state, the movable iron core 3 is released from the fixed iron core 2 and separated to the position where the variable magnetic gap 4 is at its maximum.

FIG. 3 is a characteristic diagram showing the relationship between the suction force and the stroke of the movable core 3, and the right end shows a state in which the movable core 3 is attracted to the fixed core 2. In this characteristic diagram, Fl is the suction force of the present invention and the suction force of the general structure explained in FIG. 6, and F2 is the suction force of the conventional one explained in FIG. 7 or FIG. 9. Attractive force F1 is caused by the fact that one end surface 3a of movable core 3 that is attracted to fixed core 2 is all effectively used as a facing area, whereas attracting force F2 is caused by providing a buffer member on the movable core 2, F over the entire stroke, causing a decrease in area and an increase in magnetic resistance.
l>F2.

FIG. 4 shows a second embodiment of the present invention, in which the vibration energy absorber is replaced by magnetic fluids 2h and 2h instead of the magnetic particles of the first embodiment. In this case, hollow space 2
Magnetic fluid 2h, 2 equivalent to approximately 100% of the volume of g
Built-in h. This also provides substantially the same effects as the first embodiment.

FIG. 5 shows a third embodiment of the present invention, in which the structure of the movable iron core 2 is changed. That is, the movable iron core 2 has a bottomed cylindrical body 3e and a lid body 3f made of plastic, and contains a magnetic fluid 3h in a hollow space 3g formed by these. The thickness t of the bottom of the bottomed cylindrical body 3e needs to be as thin as possible in terms of strength, but since the facing surface is a substantially flat surface, the suction force does not decrease as much as in the conventional example.

The attraction force characteristic of this product is F3 in FIG.

However, since only the thickness t of the bottom corresponds to the magnetic gap, it is inevitable that the attractive force F1 will be horizontally moved by the thickness t and will be slightly reduced.

In the first and second embodiments, the vibration energy absorber is built in both iron cores 2.3, but it may be built in only one of them.

Further, in each of the embodiments, a plunger type electromagnet device has been described, but the present invention is not limited to this, and can be applied to a flapper type or other types of electromagnet devices.

〔Effect of the invention〕

Since the electromagnet device of the present invention is configured as described above, when the movable iron core collides with the fixed iron core, the vibration energy absorber absorbs and alleviates the vibration (impact) energy to reduce the operating noise, and in the suction state, The movable iron core is reliably attracted to the fixed iron core, and a decrease in suction force can be suppressed.

[Brief explanation of the drawing]

Fig. 1 shows a first embodiment of the present invention, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view, Fig. 2 is an exploded perspective view of the main parts, and Fig. 3 is a cross-sectional view. , its stroke-attraction force characteristic diagram, Figure 4, is
This shows a second embodiment of the present invention, in which (a) is a vertical cross-sectional view;
(b) is a cross-sectional view, FIG. 5 shows a third embodiment of the present invention, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view, and
The figures show the - ship side, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view, and Figure 7 is a conventional example, (a) is a longitudinal cross-sectional view, (b) is a vertical cross-sectional view. 8 is a longitudinal sectional view showing its operating state, and FIG. 9 shows another conventional example, (a) is a longitudinal sectional view, (b) is a horizontal sectional view, and FIG. The figure is a longitudinal sectional view showing its operating state. 1--Yoke, 2-Fixed iron core, 2a--Tip surface, 2b--Base end, 2
e-bottomed cylindrical body, 2f-lid body, 2g--hollow space, 2h--vibration energy absorber (V!L particle or magnetic fluid) 3-movable iron core, 3a--one end surface, 3b - the other end, 3
e・-bottomed cylinder, 3f-lid, 3g--hollow space, sh-vibration energy absorber (magnetic particles or magnetic fluid) 4-variable magnetic gap, M-magnetic circuit, 5-coil , 6-...Coil frame.

Claims (3)

[Claims] (1) It has a magnetic circuit formed by a yoke, a fixed core, a movable core, a variable magnetic gap between the fixed core and the movable core, and a coil for flowing magnetic flux through this magnetic circuit, and controls the excitation of the coil. What is claimed is: 1. An electromagnet device in which a movable core is attracted to and released from a fixed core by doing so, characterized in that a vibration energy absorber is built into at least one of the fixed core and the movable core. (2) The electromagnet device according to claim (1), wherein the vibration energy absorber is a particle of a magnetic material. (3) The electromagnet device according to claim (1), wherein the vibration energy absorber is a magnetic fluid.