JPH01157506A - Solenoid - Google Patents

Abstract

PURPOSE:To prevent an attractive force of a solenoid from being reduced hardly even when a movement distance becomes large by a method wherein two or more magnetic substances are arranged one after another from the inside of a hollow iron core to the other end side of an excitation coil via a magnetic reluctance. CONSTITUTION:Two or more spherical magnetic substances 18 are arranged to be adjacent to one another in an axis core position of a bobbin 12; one end of the arranged spherical magnetic substances 18 is inserted into a hollow iron core 15; the other end comes into contact with a magnetic yoke 14. The spherical magnetic substances 18 are put in and inserted into a nonmagnetic pipe 19. When a selfholding type is adopted, a permanent magnet 21 is fixed to the upper part of the nonmagnetic pipe 19 coming into contact with the magnetic yoke 14. Magnetic flux generated when an electric current flows to an excitation coil 11 flows from an inner end of the hollow iron core 15 to the side of the magnetic substances 18 on the side of the permanent magnet 21; the hollow iron core 15 is attracted to the inside of the excitation coil 11. Even when the electric current to the excitation coil 11 is cut off in a state that the hollow iron core 15 is brought into contact with the permanent magnet 21, the hollow iron core 15 is attached to the permanent magnet 21 and becomes a self-holding state. By this setup, even when a movement distance of the iron core becomes large, a self- holding force is never reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field-I This invention relates to a solenoid that attracts a plunger (iron core) by passing a current through an excitation coil.

"Conventional 0) Technology" The conventional solenoid has an excitation coil 11 as shown in Fig. 8.
is wound on the bobbin 12, and an iron core 13 is attached to one end of the bobbin 12.
A magnetic yoke 14 is provided which is inserted into and out of the bobbin 12 from the other end of the bobbin 12, passes outside the exciting coil 11, and reaches the outer peripheral surface of the iron core 13.

When a current is applied to the excitation coil 11, the iron core 13 is attracted and collides with the magnetic yoke 14. As the moving distance of the iron core 13 increases, the attraction force of the iron core 13 decreases in inverse proportion to the square of the distance, resulting in the characteristics shown in FIG. 9, for example. For this reason, it has generally been considered difficult to obtain a moving distance of 1/2 or more of the outer diameter of the exciting coil 11Q).

``Means for Solving the Problems'' θ) According to the invention, the iron core that can be freely inserted into and taken out from one end of the excitation coil is a hollow iron core that has a through hole in its axis. 0) A plurality of magnetic bodies are sequentially arranged from inside the hollow core to the other end of the excitation coil via magnetic resistance. A magnetic yoke magnetically coupled to the array ends of this magnetic material is provided outside the excitation coil.

When a current is passed through the excitation coil, the magnetic flux generated at that time flows between the inner end of the core and the magnetic material, creating an attraction between them, and the hollow core is attracted into the excitation coil. If a taper is formed on the inner curved surface of the iron core, the performance will be further improved.

"Embodiment" FIG. 1 shows an embodiment of the present invention, and parts corresponding to those in FIG. 8 are given the same reference numerals. In this invention, the iron core 1
5 is a hollow core having a through hole 16 formed in its axis. Further, in this example, the curved surface within the inner end of the hollow core 15 is a tapered surface 17. A plurality of spherical magnetic bodies 18 are sequentially arranged adjacent to each other at the axial center position of the pobbin 12, one end of the array of spherical magnetic bodies 18 is inserted into the hollow core 15, and the other end is in contact with the magnetic yoke 14. There is. The spherical magnetic body 18 is fitted and inserted into a non-magnetic vibe 19, and one end of the non-magnetic vibe 190) is fixed to the magnetic yoke 14.
The other end of the non-magnetic vibrator 19 is constricted to form a spherical magnetic body 18
will not be left out. In addition, in this example, when the self-holding type is used, the non-magnetic vibrator 1 is in contact with the magnetic yoke 14.
A permanent magnet 21 is fixed on 9.

Each contact between adjacent spherical magnetic bodies 18 is a point contact, and the magnetic resistance of the contact portion is relatively high. In other words, portions with low magnetic resistance and portions with high magnetic resistance are arranged alternately. That is, the magnetic bodies 18 are arranged through magnetic resistance, and the magnetic flux generated when a current is passed through the excitation coil 11 is directed from the inner end of the hollow core 15 to the permanent magnet 21 side θ.
) flows to the magnetic body 18 side, and the hollow iron core 15 is connected to the excitation coil 11
sucked inside. Even if the current to the excitation coil 11 is cut off while the hollow core 15 is in contact with the permanent magnet 21, the hollow core 15 is attracted to the permanent magnet 21 and becomes a self-holding state. To release this self-holding state, the excitation coil 11 may generate a magnetic field that cancels the magnetic field produced by the permanent magnet 21.

In the above description, by arranging a buffer material in place of the permanent magnet 21, it is also possible to provide a sound deadening effect without affecting the characteristics.

The magnetic body 18 is not necessarily tightly fixed; for example, as shown in FIG. 3, some play 23 may exist within the magnetic body 18. In addition, the magnetic material 18 is connected to the non-magnetic pipe 1.
For example, as shown in FIG.
8 may be insert molded into the resin material 24. The magnetic body 18 is not limited to a spherical shape, but may have a curved spherical shape as shown in FIG. 5, for example. Alternatively, it may have a conical shape as shown in FIG.

In the above description, magnetic resistance is provided by point-contacting the magnetic bodies 18, but as shown in FIG. You may let them.

"Effects of the Invention" According to the configuration of this invention as described above, a large moving distance can be obtained. For example, if the excitation coil 11 has an outer diameter of 45 mm, a length of 94 mm, a hollow iron core of 15 Q), an outer diameter of 16 mm, an inner diameter of 109 mm, and a diameter of the spherical magnetic body 18 of 10 mm.
When used individually, the moving length of the hollow core 15 could be set to 60 words by applying a load of 400y, and with no load, the moving length could be set to 80Mb. - In the case of the conventional solenoid shown in Figure 3, if the shape is the same, the core travel length is 50 mm even without load.
Words were the limit.

Further, the solenoid 0) suction car moving distance characteristic of the present invention hardly decreases even if the moving distance becomes large, as shown in FIG. Moreover, by increasing the arrangement length of the magnetic bodies 18, the moving distance of the hollow core 15 can be increased.

In conventional self-holding type solenoids, the self-holding force tends to decrease due to the relationship between the iron core and the opposite part of the fixed receiver as the moving distance increases. There is no such effect.

It is sufficient that the hollow core 15 has a hollow portion where the spherical magnetic body 18 is inserted.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of a solenoid according to the present invention, the second factor is its suction car movement distance characteristic diagram, FIGS. 3 and 4 are a cross-sectional view showing a partial modification of FIG. 5
Figures 7 to 7 are cross-sectional views showing other embodiments of the present invention, Figure 8 is a sectional view showing a conventional solenoid, Figure 9 is a cross-sectional view showing a conventional solenoid,
The figure is a conventional Q] solenoid suction car movement distance characteristic diagram. Patent applicant: Hoshi Denki Seizo Co., Ltd. Representative: Kusano Takubu Tanikuyo N -5m Japanese table

Claims (1)

[Claims] (1) An excitation coil, a hollow core provided on one side of the excitation coil so as to be freely removable, one end of which is inserted into the cavity of the hollow core, and the other end of which is disposed on the other side of the excitation coil. a magnetic material array arranged sequentially via magnetic resistance; and a magnetic material array arranged around the excitation coil, one end of which is magnetically coupled to the circumferential surface of the hollow iron core, and the other end of which is magnetically coupled to the other end of the magnetic material array. and a magnetic yoke coupled to the solenoid.