JPH0786028A - Linear pin actuator - Google Patents

Abstract

PURPOSE:To enable a linear pin actuator to be used for multipin display by a method wherein parts of both ends of pins are inserted into respective paired holes and when coils are supplied with a current, respective pins reciprocally oscillate in linear mode so that magnetically stabilized points may be presented at least at two positions within the range of reciprocal oscillation thereof. CONSTITUTION:Plural holes 36a, 36b, 36c... (38a, 38b, 38c...) passing through permanent magnets 32a, (32b) and a yoke 30 are bored in a magnetic circuit. Next, parts of both ends of pins 40a are inserted into respective paired holes 36a and 38a, 36b and 38b, 36c and 38c. However, at least parts of respective pins 40a are composed of Fe while the periphery thereof is wound up with coils 42a. Furthermore, when the coils 42a are supplied with a current, the pins 40a oscillate reciprocally in linear mode so that magnetically stabilized points may be presented at least in two positions within the range of reciprocal oscillation thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear pin actuator that linearly reciprocally vibrates a pin. Linear pin actuators are used in particular for pin displays that display characters and graphics.

[0002]

2. Description of the Related Art As described above, linear pin actuators are often used in pin displays for displaying characters and figures.

A pin display using a linear pin actuator displays characters and figures as follows. The plurality of pins provided on the linear pin actuator can independently reciprocally vibrate by the pin moving mechanism. Therefore, each pin can be independently reciprocally oscillated, and the tips of some pins can be projected to the display plate surface. The protruding portions of the pins become dots that form characters and figures, and these dots are appropriately aggregated to display characters and figures.

Conventionally, a small motor or a piezoelectric actuator has been used as a pin moving mechanism in a linear pin actuator. Step motors and DC brushless motors are generally used as small motors. A vibration actuator is suitable for this application.

The small motor, a partial cutaway of which is shown in FIG.
The linear vibration actuator is a permanent magnet 10a,
10b and a mover 14 composed of a magnetic material portion 12 excited by these, a stator back yoke 16 and a coil 18 inserted therein. The mover 14 and the stator back yoke 16 form a magnetic path, and the protrusions 20a and 20b of the mover 14 and the stator back yoke 16 overlap each other, and the protrusions 20b and 20c of the mover 14 and the stator back yoke 16 overlap. It has two magnetic stable points, that is, an overlapping point. The mover 14 reciprocates between these two magnetically stable points.

In order to use it as a pin moving mechanism in a linear pin actuator, it is sufficient that there are at least two stable points. Therefore, the linear vibration actuator of FIG. 2 can be used as a linear pin actuator.

However, since the linear vibration actuator of FIG. 2 has a complicated structure and the coil 18 is provided in the stator back yoke 16, it is difficult to reduce the outer diameter of the entire linear vibration actuator. .

As a result of trying the difficulty of manufacturing a small motor having a small outer diameter, for example, an outer diameter of 4.2 m.
m stepping motor has been realized and applied as a three-dimensional information device for the visually impaired. The stepping motor has an advantage that the pin speed, the pin position, etc. can be arbitrarily changed within the range of the characteristics of the motor, and each pin can be driven independently. Also, since each pin has a high degree of freedom, it is suitable for three-dimensional display.

However, in the above stepping motor,
Since the pins and the motors have a one-to-one correspondence, when the pin display is applied, as many motors as the pins are required. Therefore, with a pin display having a large number of pins, the size of the entire pin display device becomes too large, which is not suitable for practical use. In addition, since a large number of motors are required, it becomes expensive. Therefore, the stepping motor has a drawback that it is not suitable for a pin display that requires a large number of pins.

On the other hand, a pin display using a piezoelectric actuator as a pin moving mechanism has been realized. However, since the piezoelectric actuator itself has a small amplitude of pin vibration, it must be combined with an amplifier, and it is difficult to miniaturize it. Therefore, it also has a drawback that it is not suitable for a pin display having a large number of pins. Actually, the number of pins of the pin display by the realized piezoelectric actuator is about 100 to 200.

However, there is a demand to increase the number of characters displayed on the pin display and to improve the image quality of the display graphic, and for that purpose, thousands of pins are required. Therefore, there has been a demand for a linear pin actuator that can be used for a pin display having a large number of pins.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a linear pin actuator which can be used for a pin display having a large number of pins.

[0013]

Means for Solving the Problems 1 magnetized in the thickness direction
A pair of permanent magnet plates facing each other and provided inside the yoke, and a plurality of holes penetrating the permanent magnet plate of the magnetic circuit and the yoke on the back surface of the permanent magnet plate are formed on the facing surface. A plurality of pins are provided so as to form a pair, at least a part of which is made of iron, and a coil is wound around each of the pins. Each of the pins is linearly reciprocally oscillated when a current is applied to the coil, and there are at least two magnetic stable points in the range of the reciprocal oscillation. A featured linear pin actuator is provided.

[0014]

1 is a partial sectional partial view of a linear pin actuator according to the present invention. Inside the yoke 30, a pair of permanent magnets 32a and 32b magnetized in the thickness direction are provided with different poles facing each other, forming a magnetic circuit. Thereby, for example, the magnetic field in the direction of the arrow 34 is changed to the opposite magnet 3
It occurs between 2a and 32b.

In the above magnetic circuit, the permanent magnet 32a (32
b) and a plurality of holes 36a, 36 penetrating the yoke 30
b, 36c, ... (38a, 38b, 38c, ...) Are provided. Although only a few holes are shown in FIG. 1, actually, as many holes as necessary are provided. However, these holes should be paired on opposite sides, that is, 36a.
And 38a, 36b and 38b, 36c and 38c, ... Are provided in pairs.

The above-mentioned pair of holes 36a and 38a,
Part of both ends of the pins 40a, ... Are inserted into each of 36b and 38b, 36c and 38c ,. Although only one pin 40a is shown in FIG. 1 for the sake of simplicity, in actuality, only the number of pairs of holes is provided.

However, at least a part of each of the pins 40a, ... Is made of iron, and the coils 42a ,. Further, the pins 40a, ... Are the coils 42a ,.
When an electric current is applied to the motor, it reciprocally oscillates linearly, and there are at least two magnetic stable points in the range of vibration. In FIG. 1, the pin oscillates vertically and reciprocally, and the pin moves upward (the pin 40a in FIG.
There are magnetic stable points at two locations, the position () and the lower side. Furthermore, the plurality of pins 40a, ... Can reciprocate independently.

As the permanent magnets 32a and 32b, sintered magnets may be attached, or bond magnets may be integrally formed with the yoke 30. The coils 42a, ... May use simple copper windings or print coils.

The mechanism of vibration of the pins 40a, ... Will be described below. When the pin 40a is in the position shown in FIG. 1, the pin 40a
Since a part of is made of iron, it is attracted to the permanent magnet 32a and is stable. At this time, a current is passed through the coil 42a,
The magnetic pole of the attraction surface of the pin 40a with respect to the permanent magnet 32a is made to be the same as the magnetic pole of the attraction surface of the permanent magnet 32a. As a result, the attraction surfaces repel each other, and the pin 40a moves away from the permanent magnet 32a and moves downward. When the current flowing through the coil 42a is stopped here, the pin 40a can approach the permanent magnet 32b without repulsing it. At this time, since part of the pin 40a is made of iron,
It can be stabilized by being attracted to the permanent magnet 32b. As described above, the pin can reciprocate in the linear pin actuator of FIG.

The attraction strength and the moving speed of the pin to the permanent magnet can be adjusted by changing the magnetic field strength between the permanent magnets and the shape of the pin. Therefore, the linear pin actuator may be designed according to its application.

As can be seen from FIG. 1, the feature of the linear pin actuator according to the present invention is that there is only one magnetic circuit common to all pins. That is, this is significantly different from the conventional linear pin actuator in which each pin is provided with a separate magnetic circuit (the pins and the motors have a one-to-one correspondence).

Since the magnetic circuit is common, the pins can have a simple shape and the coil can also have a simple winding. Therefore, the outer diameter of the coil wound around the pin can be made very small, and a pin display with a large number of pins (a few thousand) can be realized.

[0023]

With the linear pin actuator according to the present invention, a pin display having a large number of pins (a few thousand) can be realized. As a result, it has become possible to increase the number of characters displayed on the pin display and improve the image quality of the displayed graphic.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a linear pin actuator according to the present invention.

FIG. 2 is a diagram for explaining the structure of a conventional typical linear vibration actuator.

Claims (1)

[Claims] 1. A magnetic circuit comprising a pair of permanent magnet plates magnetized in the thickness direction facing each other and provided inside a yoke, the permanent magnet plate of the magnetic circuit and a yoke on the back surface of the permanent magnet plate. A plurality of holes penetrating through are provided so as to form a pair on the opposite surfaces, at least a part is made of iron, and a plurality of pins around which a coil is wound, and a part of both ends of the pin Are provided so as to be inserted into each of the pair of holes, and each of the pins linearly reciprocally vibrates when a current is applied to the coil, and at least within the range of the reciprocal vibration. A linear pin actuator characterized in that there are two magnetic stable points.