JP2001060512A - Dc solenoid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To the reduce a power consumption and realize an superior response, and improve flexibility of the combination structure while a member giving a displacement. SOLUTION: In this solenoid, a pair of yokes 1 and 2 in which first flat plates 11 and 21 and second flat plates 12 and 22 facing to each other at a set interval and distance are made integrally are fitted to the ends of a pole piece 5 at the center of a coil 3, and a permanent magnet 7 of a movable body 6 is placed between the pair of yokes 1 and 2. When the coil 3 is energized, an attraction force and a repulsion force are produced, and they works on the permanent magnet 7, thereby causing the movable body 6 to move. Thus power consumption is reduced, and an superior response a can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC solenoid used for various devices such as audio equipment, OA equipment, home electric appliances, automobiles, vending machines and the like.

[0002]

2. Description of the Related Art As a DC solenoid, there is one having a structure in which a plunger moves in an axial direction by energizing a coil wound around a bobbin. An example is shown in FIG.

The DC solenoid shown in FIG. 7 includes a bobbin 101 formed of a non-magnetic material such as a synthetic resin into a substantially cylindrical shape, a coil 102 wound on the bobbin 101, a yoke 103 for accommodating the bobbin 101, and a bobbin 101. Central through hole 1
A plunger (movable iron core: permanent magnet) 104 having a substantially cylindrical shape, which is disposed in the inner side of the bobbin 101, and which is disposed in the center through hole 101 a of the bobbin 101.
3 and a return spring 106 that presses the plunger 104 toward the return side. The magnetomotive force generated when the coil 103 is energized causes the plunger 104 to rotate the return spring 106. This is a monostable DC solenoid having a structure that moves toward the fixed pole 105 against the elastic force and is attracted and held by the fixed pole 105. In the DC solenoid having the structure shown in FIG.
Since 1 may be deformed and cause malfunction,
The metal pipe 107 made of brass or the like is inserted into the
01a to increase the dimensional accuracy of the moving part of the plunger 104.

As the DC solenoid, in addition to the above-described monostable DC solenoid, two coils are provided in the yoke, and the direction of the current supplied to each of the coils is changed so that the plunger is moved to two positions. A bistable type (two-position stable type) DC solenoid which is moved to a position is also generally known (Japanese Patent Application Laid-Open No. 8-288129).

[0005]

According to the monostable type DC solenoid as shown in FIG. 7, it is necessary to keep the coil energized at all times when the plunger is attracted and held. In addition, there is a problem that the temperature of the coil rises due to constant power supply.

Also, when the plunger is in the return state,
Since the distance between the plunger and the fixed pole is the largest,
Large suction force (magnetomotive force) at the beginning of movement during suction holding
Therefore, in order to obtain high responsiveness, it is necessary to instantaneously apply a large current to the coil. Furthermore, since the plunger (permanent magnet) is placed in the coil during suction holding, the characteristics of the permanent magnet may deteriorate (demagnetize) due to long-term use, and the responsiveness (movement) may deteriorate. .

In addition, since the plunger is a cylindrical (or quadrangular) metal member, the connection structure with a member (for example, an operating rod) that is displaced by a solenoid is limited to a specific structure. Also, there is a disadvantage that the degree of freedom in designing a product to which the solenoid is applied is greatly restricted.

On the other hand, the bistable DC solenoid requires two exciting coils, and thus has a problem that the product cost is high. In addition, since the plunger is a cylindrical (or quadrangular) metal member, there is a problem similar to that of a monostable DC solenoid. A bistable DC solenoid having one excitation coil has already been proposed (for example, Japanese Patent Application Laid-Open No. H10-270243).
In the case of this proposed technique, the structure of the plunger is complicated, so that significant cost reduction cannot be expected, and the problem of the connection structure between the plunger and the operating rod or the like still remains.

The present invention has been made in view of such circumstances, and has as its object to provide a DC solenoid which consumes little power, has good responsiveness, and has a high degree of freedom in connection structure with a member which gives displacement. .

[0010]

SUMMARY OF THE INVENTION A DC solenoid according to the present invention comprises a coil wound around a bobbin, a pole piece disposed in a central through hole of the bobbin, and a pair of yokes attached to each end of the pole piece. And a non-magnetic movable body having a permanent magnet. And in each yoke,
A first and a second opposing flat plate, which are parallel to each other at a predetermined interval and are displaced from each other in the parallel direction, are integrally formed. The first opposing flat plate of the yoke and the second opposing flat plate of the other yoke, and the first opposing flat plate of the other yoke and the second opposing flat plate of the one yoke are located on the same plane. In addition, the first opposed flat plate and the second opposed flat plate are configured to face each other, and a permanent magnet of a movable body is arranged between the pair of yokes via a nonmagnetic sheet. It is characterized by having.

According to the DC solenoid of the present invention, by changing the direction of the current flowing through the coil, the permanent magnet of the movable body is moved between the first opposed flat plates of the pair of yokes (the first position).
To the two opposing flat plates (second position). The principle is described below.

First, as shown in FIG. 1, between a pair of yokes 1, 2, a surface facing each of the yokes 1, 2 is S.
A permanent magnet 7 magnetized so as to be a pole and an N pole is arranged. Now, when the permanent magnet 7 is at the first position P1 (FIG. 1A), the coil 3 is energized so that the upper end of the pole piece 5 becomes the N pole and the lower end thereof becomes the S pole. When a magnetic force is generated, the magnetic flux flowing through the coil 3 and the pair of yokes 1 and 2 causes the first opposing electrodes 11 and 21 and the second opposing electrodes 12 and 22 to have polarities as shown in FIG. Is located on the first opposed flat plate 1.
While receiving the repulsive force from the first and second plates 21 and 21, they are attracted by the second opposed flat plates 12 and 22 to move from the first position P1 to the second position P2 (FIG. 1B).

On the other hand, when the permanent magnet 7 is at the second position P2 (FIG. 4A), when a current in the opposite direction is supplied to the coil 3, the coil 3 and the pair of yokes 1, 2 are supplied. The flowing magnetic flux is reversed, whereby the first opposing electrodes 11 and 21 and the second opposing electrodes 12 and 22 have polarities as shown in the figure, and the permanent magnet 7 at the second position P2 is in the second position. While receiving repulsive force from the opposing flat plates 21 and 22 of
It is drawn by the first opposing flat plates 11 and 21 and moves from the second position P2 to the first position P1 (FIG. 4).
(B)).

The permanent magnet 7 moving as described above is positioned at the position where the magnetic flux density becomes maximum at the first position P1 or the second position P2, that is, the first opposed flat plate 11,
It is suction-held at the center position of 21 or the center position of the second opposed flat plates 12 and 22. Therefore, in the DC solenoid of the present invention, the distance between the centers of the first opposed flat plates 11, 21 and the second opposed flat plates 12, 22 is the stroke.

[0015] In the DC solenoid of the present invention,
The non-magnetic sheet provided between the pair of yokes and the permanent magnet functions as a spacer for preventing a malfunction such as the permanent magnet being caught by the yoke and stopping when the permanent magnet moves. .

Here, in the DC solenoid according to the present invention, at least one of the pair of first opposing flat plates or the pair of second opposing flat plates faces inwardly at positions corresponding to each other. If the protruding protrusions are formed, the density of the magnetic flux flowing between the protrusions becomes higher than that of the other portions. Therefore, the accuracy of the holding position of the permanent magnet at each of the first and second positions, that is, the stroke Accuracy can be increased.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a DC solenoid according to an embodiment of the present invention, and FIG. 2 is a plan view of the embodiment. FIG.
FIG. 3 is a perspective view extracting and showing a coil and a pair of yokes.

The DC solenoid according to the present embodiment includes a pair of yokes 1 and 2, a coil 3 wound around a bobbin 4, a pole piece 5, and a non-magnetic movable body 6 having a permanent magnet 7. The slider 8 (a sheet made of a non-magnetic material) is mainly configured.

The bobbin 4 is a cylindrical member formed by molding a synthetic resin such as an ABS resin, and has a flange integrally formed at both ends. The pole piece 5 is made of iron, and has a cylindrical main body 50 fitted into the central through hole 4a of the bobbin 4;
Fixed shafts 51, 5 protruding from both end surfaces of the
2 are integrally formed.

The pair of yokes 1 and 2 are made of a steel plate (eg, SP
CC, 1.6 mm in thickness) and are bent into the same shape, and the first opposed flat plates 11 and 21 and the second opposed flat plate 1
2, 22 and the first opposing flat plates 11, 21 and the second
Connecting plates 13 and 23 for connecting the opposed flat plates 12 and 22 to each other;
The attachment plates 14 and 24 to the pole piece 5 are integrally formed.

In each of the yokes 1 and 2, the second opposed flat plates 12 and 22 are formed continuously with the mounting plates 14 and 24. The second opposed flat plates 12 and 22 and the first opposed flat plate 1
1 and 21 are formed in parallel with each other with an interval corresponding to the dimension between the end faces of the bobbin 4. However, the first opposed flat plates 11 and 21 and the second opposed flat plates 12 and 22 are not opposed to each other, and the first opposed flat plates 11 and 21 are located on the front side with respect to the second opposed flat plates 12 and 22. (A side away from the mounting plates 12, 24) at a position shifted by a predetermined distance (a distance corresponding to a stroke). The mounting plate 1
In holes 4 and 24, holes 14a, 2
4a is processed.

When the pair of yokes 1 and 2 are attached to the pole piece 5, as shown in FIGS. 1 and 3, the first opposing flat plate 11 of one yoke 1 and the first The two opposing flat plates 22 and the first opposing flat plate 21 of the other yoke 2 and the second opposing flat plate 12 of the one yoke 1 are located on the same plane, respectively. 21 and the second opposed flat plates 12 and 22
They are configured to face each other.

On the other hand, the movable body 6 is a resin molded product, and the permanent magnet 7 is integrally formed by insert molding. The movable body 6 is provided with a connection shaft 61 at the tip, and an elongated hole 6 a is opened between the connection shaft 61 and the permanent magnet 7 to avoid interference with the coil 3. The permanent magnet 7
The ferromagnetic material (magnet steel) processed into a rectangular parallelepiped is magnetized such that one end (upper end in the figure) is an S pole and the other end (lower end) is an N pole.

The slider 8 is disposed between the pair of yokes 1 and 2 and the permanent magnet 7, and is a spacer for preventing the malfunction such as the movement of the permanent magnet 7 being stopped by being caught by the yokes 1 and 2 when the permanent magnet 7 moves. Function as The slider 8 may be made of a synthetic resin such as polypropylene, polyacetal, polyethylene, or vinyl chloride, or a nonmagnetic sheet such as aluminum or brass. The better the thickness of the slider 8 is, the better the mechanical strength can be obtained.

The DC solenoid having the above structure is provided with a bobbin 4
After the coil 3 is wound around the bobbin 4 and the pole piece 5 is fitted into the central through hole 4a, the coil 3 is inserted into the long round hole 6a of the movable body 6, and in this state, the slider is placed above and below the permanent magnet 7. 8, and a pair of yokes 1, 2 are arranged above and below the coil 3, and mounting holes 14 a, 2
4a is inserted into the fixed shafts 51, 52 of the pole piece 5,
Next, the permanent magnets 7 of the movable body 6 can be assembled by crushing the distal ends of the fixed shafts 51 and 52 and fixing the yokes 1 and 2 to the pole piece 5 and the bobbin 4. , Located between the pair of yokes 1 and 2,
A first position P1 between the first opposed flat plates 11 and 21;
Between the opposing flat plates 12 and 22 between the second positions P2.

In the DC solenoid of this embodiment, when the permanent magnet 7 is at the first position P1, as shown in FIG. When a magnetomotive force is generated such that the middle and upper ends are N poles and the lower end is S poles, the permanent magnet 7 moves from the first position P1 to the second position P2 based on the above-described operation principle ( FIG. 4 (B)).

On the other hand, when the permanent magnet 7 is at the second position P2 (FIG. 4 (A)), a current in the opposite direction is supplied to the coil 3 so that the upper end of the pole piece 5 in FIG. When a magnetomotive force is generated such that the pole and the lower end become the N pole, the permanent magnet 7 moves from the second position P2 to the first position P1. Thus, in the DC solenoid of the present embodiment, the coil 3
The permanent magnet 7, that is, the movable body 6 can be moved to two positions by changing the direction of the current flowing through the magnet.

After the permanent magnet 7 is moved to the first position P1 or the second position P2, even if the energization to the coil 3 is stopped, the magnetic force of the permanent magnet 7 itself (between the yoke 1, 2). , The position of the permanent magnet 7 is held. When it is desired to increase the holding force at each of the positions P1 and P2, the permanent magnet 7 is moved to the first position P1 or the second position P1.
After moving to step 2, the energized state may be maintained.

In the above embodiment, an example is shown in which the permanent magnet 7 is fixed to the movable body 6 by insert molding. However, the present invention is not limited to this. Alternatively, a method of fixing the permanent magnet to the holding portion, a method of fixing the permanent magnet to the movable body with an adhesive, or the like may be adopted.

Here, in the present embodiment, as shown in FIG. 5, the first opposing flat plates 11, 21 and the pair of second opposing flat plates 12, 22 are respectively inwardly positioned at positions corresponding to each other. Projecting convex portions 11a, 21a and convex portion 12
a and 22a may be formed. In this case, since the density of the magnetic flux flowing between the protruding portions 11a and 21a and the protruding portions 12a and 22a facing each other is higher than that of the other portions, the permanent magnet at each of the first position P1 and the second position P2. Magnet 7
, The accuracy of the holding position, that is, the accuracy of the stroke can be improved. In addition, such a convex part is formed by a pair of first opposed flat plates 11 and 21 or a pair of second opposed flat plates 12 and 22.
The same effect can be obtained even if it is provided in any one of them.

Further, instead of the above-described configuration of the convex portion,
By devising the shape of the permanent magnet, the positional accuracy can be improved. Specifically, as shown in FIGS. 6A to 6D, hemispherical members (ferromagnetic material or permanent magnet) 171 and 172 are bonded and fixed to the upper and lower surfaces of the rectangular parallelepiped permanent magnet 17 ( FIG. 6A), rectangular parallelepiped permanent magnet 27
Triangular members (ferromagnetic material or permanent magnet) on the upper and lower surfaces 2
Permanent magnet 37 having a structure in which magnets 71 and 272 are bonded and fixed (FIG. 6B), or a rectangular parallelepiped (ferromagnetic material) having a diamond-shaped side surface is magnetized diagonally and both ends are cut.
(FIG. 6C). Also, after forming the ferromagnetic powder into a shape as shown in FIG.
A permanent magnet 47 magnetized so that the convex portions 471 and 472 become the S pole and the N pole, respectively, can also be mentioned.

[0033]

As described above, according to the DC solenoid of the present invention, a pair of yokes in which first and second opposed flat plates parallel to each other are formed at a predetermined interval and distance are formed by a coil. A structure that attaches to the end of the center pole piece and arranges the permanent magnet of the movable body between a pair of yokes, and moves the movable body by the attraction and repulsion acting on the permanent magnet by energizing the coil As a result, power consumption can be reduced and excellent responsiveness can be obtained. Further, since the shapes and dimensions of the yoke and the permanent magnet can be made smaller than those of the conventional product, the size of the product can be reduced. Further, since the permanent magnet is not placed in the coil, there is little problem of deterioration of the characteristics of the permanent magnet, and stable responsiveness can be obtained for a long period.

Furthermore, the permanent magnet need not be rod-shaped, but can be of any shape, and can be formed integrally with the movable body, so that the connection structure to the member for applying displacement is extremely simple. This increases the degree of freedom in designing various products to which the DC solenoid is applied. Further, since the stroke is determined by the distance between the first opposed flat plate and the second opposed flat plate of the yoke, an arbitrary stroke can be easily set regardless of the shape and dimensions of the coil and the permanent magnet. It is also possible to make the stroke length longer than before.

The DC solenoid according to the present invention has an effect that a bistable DC solenoid can be realized with a simple structure without complicating the structure and the like of the permanent magnet with one coil.

[Brief description of the drawings]

FIG. 1 is a diagram showing both a longitudinal sectional view and an operation explanatory view of an embodiment of a DC solenoid of the present invention.

FIG. 2 is a plan view of the embodiment of FIG.

FIG. 3 is a perspective view showing a pair of yokes and coils extracted.

FIG. 4 is an operation explanatory diagram of the embodiment of FIG. 1;

FIG. 5 is a view showing a modification of the yoke.

FIG. 6 is a view showing a modification of the permanent magnet.

FIG. 7 is a cross-sectional view showing an example of a conventional DC solenoid.

[Explanation of symbols]

 1, 2 Yoke 11, 12 First opposing flat plate 12, 22 Second opposing flat plate 13, 23 Connecting plate 14, 24 Mounting plate 3 Coil 4 Bobbin 4a Center through hole 5 Pole pieces 51, 52 Fixed shaft 6 Moving body 6a Oval hole 7 permanent magnet

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroshi New Year 104 F-Term (reference) 5E048 AB10 AC05 AD07 2-7-7 Higashi Nara, Ibaraki-shi, Osaka

Claims (2)

[Claims] 1. A non-magnetic material having a coil wound around a bobbin, a pole piece disposed in a central through hole of the bobbin, a pair of yokes attached to each end of the pole piece, and a permanent magnet. A first and a second opposed flat plate, which are arranged parallel to each other at a predetermined interval and are displaced from each other in a direction parallel to each other, and are formed integrally with each yoke; In the state of being attached to the end of the pole piece, the first opposed flat plate of one yoke and the second opposed flat plate of the other yoke, and the first opposed flat plate of the other yoke and the second opposed flat surface of one yoke The flat plates are located on the same plane, and the first
And the second opposing flat plates are opposed to each other, and the permanent magnet of the movable body is disposed between the pair of yokes via a non-magnetic sheet. Characteristic DC solenoid. 2. A pair of first opposed flat plates or a pair of second flat plates.
2. The DC solenoid according to claim 1, wherein at least one of the pair of opposed flat plates has a convex portion protruding inward at a position corresponding to each other.