JPH01259512A - Electromagnetic actuator - Google Patents

Abstract

PURPOSE:To actuate an operating member with less power supply by operating the member under conditions that when a coil has been not energized one of two attraction pieces is abutted on a coil core to permit only one gap to be formed on a magnetic path. CONSTITUTION:A coil 2 includes first and second attraction pieces 4, 5. The coil 2 is energized in a situation the second attraction piece 5 is abutted to a core of the coil 2. Hereby, the first attraction piece 4 is attracted to actuate a first operating lever 11. The second attraction piece 5 is released when the coil 2 is deenergized, to actuate a second operating lever 12. Thus, the single coil 2 actuates the two operating levers 11, 12. Accordingly, there is existent only one air gap on a magnetic path, so that magnetic reluctance in the present case is the same as prior situations where only one attraction piece is provided. Thus, the two operating levers 11, 12 can be actuated with the same power as in prior situations.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic actuator equipped with two suction pieces for use in small precision equipment such as cameras.

[Conventional technology]

Since a conventional electromagnetic actuator has one suction piece for one coil core, it goes without saying that there is also one operation member for equipment that is operated by the suction piece. Therefore, when attempting to operate a plurality of operating members using electromagnetic actuators, as many electromagnetic actuators as there are operating members are required.

[Problem that the invention seeks to solve]

When operating a large number of operating members using electromagnetic actuators, such as in a small precision machine such as a camera, equipping as many electromagnetic actuators as there are operating members is one of the reasons that hinders miniaturization of the device. It also becomes. To solve this problem, by arranging two adsorption pieces for one coil core, it becomes possible to operate two operating members with one electromagnetic magnet, reducing the number of actuators by half. You can also.

However, arranging two attraction pieces on one coil core means that there are also two gaps between the attraction piece and the coil core, which increases the magnetic resistance of the formed magnetic path. As a result, the operation member cannot be operated unless a larger amount of power is supplied than in a conventional electromagnetic magnet that has one attraction piece for one coil core.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention has a structure in which, when the coil is in a non-excited state, one of the two attraction pieces is brought into contact with the coil core, and the air gap formed on the magnetic path is operated as one. A coil core made of a magnetic material, a coil wound around the coil core, a yoke made of a magnetic material arranged parallel to the coil core, and both ends of the yoke. A first magnetic material is supported at one end thereof, is disposed at a position facing both ends of the coil core, and is made of a magnetic material and moves between an attraction position where the coil core is attracted and a separation position away from the attraction position. a second suction piece, a first operation member driven by movement of the first suction piece, a second operation member driven by movement of the second suction piece, and one by the coil core. The present invention is characterized by comprising a contact mechanism that positions and holds the other suction piece at a suction position prior to the suction operation of the other suction piece.

[For production]

When the coil is in an initial state where it is not excited, the second attraction piece is held at the attraction position by the contact mechanism. When the coil is excited, the first attraction piece attracts the coil core,
Rotating the first operating member to the second position. At this time, the second attraction piece is in contact with the coil core, and there is only one gap in the magnetic path, so when the first attraction piece is attracted, it is the same as the conventional electromagnetic magnet with one attraction piece. The first operating member is rotated by force. Further, at this time, since the second suction piece is also in the suction state, the second operating member is prevented from rotating and remains at the first position.

When the excitation of the coil is released, the first operating member returns to the first position, and the second operating member rotates to the second position.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 is an exploded view of an electromagnetic actuator embodying the present invention. In the figure, 1 is a coil core made of magnetic material, 2 is a coil core, one end of the coil core 1 is formed with a large-diameter adsorption part 1a, the other end is formed with a small-diameter protrusion 1b', and the coil After inserting the coil 2 into the core 1, the small diameter protrusion 1b
The suction part 1b is inserted into ' and fixed by welding or the like. 3
4 is a yoke forming a part of the magnetic path of the electromagnet, and 4 and 5 are adsorption pieces, each of which is narrowed at the bottom and has a tip 4.
a.

5a. Furthermore, two notches 4b are formed at the top of the suction piece 4, and two notches 5 are formed at the top of the suction piece 5.
b is formed, and the suction piece 4.5 is attached to the end 3c of the yoke 3,
Rotatably locks with 3d.

Reference numeral 6 denotes a leaf spring, which is located on the yoke 3, and has locking portions 6e on the left and right ends to prevent the suction piece 4 from being pulled out, and a leaf spring 6 on the suction piece 5.
A locking portion 6f is provided to prevent the suction pieces 4 and 5 from being pulled out.
When the plate springs are locked to the yoke 3, the locking portions 6e and 6f of the leaf springs engage with the notches 4d and 5d provided in the upper parts of the suction pieces 4 and 5, respectively. Further, spring pieces 6c and 6d are provided on the left and right sides of the locking parts 6e and 6f of the leaf spring 6, and as shown in an enlarged view in FIG.
The suction pieces 4 and 5 are urged upward with a force F by contacting less than half of the upper surfaces of the suction pieces b and 5b. As a result, the suction pieces 4, 5 receive a rotational moment M toward the inner side, that is, the suction parts 1a, lb of the coil core 1, and come into contact with the suction parts 1a, lb.

7 is a magnet holder, the yoke mounting part 7a is provided with a screw hole 7b and a boss hole 7c, and the yoke 3 and the plate spring 6 located above it are screwed into the boss 3e and screw hole 3f provided on the yoke 3. It is fixed with screw 8. At the rear of the magnet holder 7, there is a downward extending portion 7d, from which coil core holding portions 7e and 7'f extend forward from left and right.
At its tip, there are two fingers 7 each that hold the coil core.
There is an opening 7 m having diameters g and 7h, which sandwich the insides of the left and right suction plates 1a and lb of the coil core 1. The extension portion 7d of the magnet holder 7 has a screw hole 7p for fixing it to the mounting plate 9.

There is a boss hole 7q, and it can be fixed with a screw 10 screwed into a boss 9C provided on the mounting plate 9 and a screw hole 7p.

11 is a first operating lever operated by the adsorption piece 4;
A second operating lever 2 is operated by the suction piece 5, and is arranged inside the suction pieces 4 and 5, respectively.

Next, the shapes of the suction plates 1a and 1b at the tip of the core will be explained.

As shown in FIG. 3(b), the surfaces 1a and lb of the suction portion are raised surfaces consisting of a gentle spherical surface with a small curvature or a conical surface with an extremely large apex angle, and the apex Q thereof is the surface of the suction piece 4, 5. When viewed from the fulcrum S relative to the yoke 3, this is a position outside the center point of the coil core.

As a result, when the suction pieces 4, 5 are attracted to the suction parts 1a, 1b, the contact point becomes the apex Q of the raised surface, so that the distance from the fulcrum S of the suction pieces becomes constant. In addition, since the surface is a gentle spherical surface or a conical surface with an extremely large apex angle, the gap between the suction pieces 4 and 5 and the suction parts la and lb is small.
Magnetic resistance becomes smaller.

FIG. 3(a) shows that the suction part 1b and the suction piece 5 are in partial contact with each other.
A state in which they are in contact at a point P is shown, and FIG. 3(C) shows a case where the curvature of the suction portion 1b is large. In both cases, the gap is large and the suction force is small.

Next, the operation of the electromagnetic actuator of the present invention will be explained in detail.

FIG. 4 shows an initial state, in which the coil 2 is not energized. Further, the second actuating lever 12 on the left side in the drawing is locked at the position shown in the drawing by a locking mechanism (not shown) of a device to which this electromagnetic actuator is applied, and is not in contact with the suction piece 5. 5 is in contact with the suction portion 1b. On the other hand, the first operating lever 11 on the right side of the drawing is biased clockwise by a device to which this electromagnetic actuator is applied, which is also not shown, and is stopped at the position shown in the drawing. Since this biasing force is greater than the counterclockwise biasing force biased against the suction piece 4 by the spring piece 6c of the leaf spring 6, the suction piece 4 is in a state away from the suction portion 1a.

In this state, when current is applied to the coil 2, a magnetic path is formed by the coil core, the attraction part, the attraction piece, and the yoke, and the attraction bar 4 is attracted to the attraction part 1a as shown in FIG. Rotate the lever 11 counterclockwise.

On the other hand, since the suction piece 5 is in contact with the suction portion 1b, there is no change.

When the first operating lever 11 rotates counterclockwise, the locking mechanism of the device to which this electromagnetic actuator (not shown) is applied is released, and the second operating lever 11 on the left side is rotated as shown in FIG. is biased to rotate counterclockwise. However, at this point, since the coil is energized, the attraction piece 5 is attracted to the attraction part 1b, and the second actuation lever 1
2 comes into contact with the suction piece 5 and is prevented from rotating further.

Furthermore, when the current to the coil 2 is cut off, the adsorption piece 5 is released as shown in FIG. The operating lever 11 is rotated by a clockwise biasing force.

By operating the locking mechanism of the device (not shown), the second operating lever 12 is locked in a position where it does not come into contact with the suction piece 5, and returns to the initial state shown in FIG. 4.

As shown in FIG. 5, the left and right suction pieces 4 and 5 are attached to the suction portion 1a.
, lb, the magnetic path closes, the magnetic resistance decreases, and the magnetic flux density increases, leading to saturation. Since this results in wasted power consumption, the fact that the suction piece is attracted is detected by a switch (not shown) linked to the operating lever 11 or by a back electromotive current generated in the coil, and the current flowing through the coil is reduced. Figure 8 shows an example of the control circuit, which inputs a detection signal to the microcomputer and turns off one of the transistors Ql and Q2 connected to the output port of the microcomputer when the detection signal indicates that the suction piece has been adsorbed. The state is to reduce the current flowing through the coil 2.

〔Effect of the invention〕

As explained above, according to the present invention, two suction pieces are provided for one coil, and the coil is excited with the second suction piece in contact with the coil core, and the first This is possible because the first operation member is operated by the attraction operation of the attraction piece, and the second operation member is operated by the release of the second attraction piece when the coil is de-energized. Since there is only one air gap on the magnetic path of the electromagnet, the magnetic resistance is the same as a conventional electromagnetic actuator with one attraction piece, and with the same power as a conventional electromagnetic actuator, two can operate the operating members.

[Brief explanation of the drawing]

Fig. 1 is an exploded view of the electromagnetic actuator according to the present invention, Fig. 2 is an enlarged sectional view illustrating the state of engagement between the yoke and the adsorption piece, Fig. 3 is an explanatory diagram of the shape of the adsorption part at the tip of the coil core, and Fig. 4 to 7 are explanatory diagrams of the operation of the electromagnetic actuator, and FIG. 8 is a diagram of a coil energization control circuit. 1: Coil core, la, lb: Adsorption part, 2: Coil, -
3 = Yoke, 4, 5: Adsorption piece, 6: Leaf spring, 7: Magnet holder. Figure 2 (a) (b) (c)
Figure 3 Figure 8

Claims (1)

[Claims] a coil core made of a magnetic material, a coil wound around the coil core, a yoke made of a magnetic material arranged parallel to the coil core, one end of which is supported by both ends of the yoke; first and second attraction pieces made of a magnetic material that are disposed at positions facing both ends of the coil core and move between an attraction position where the coil core is attracted and a separation position away from the attraction position; A first operation member driven by the movement of the first attraction piece, a second operation member driven by the movement of the second attraction piece, and prior to the suction operation of one attraction piece by the coil core. An electromagnetic actuator comprising: a contact mechanism for positioning and holding the other suction piece at a suction position.