JPH1052019A - Electromagnetic actuator - Google Patents

Abstract

(57) [Problem] A conventional linear motion type electromagnetic actuator has a problem that its configuration is complicated and heavy in order to secure necessary driving force and achieve required positioning accuracy. SUMMARY OF THE INVENTION An object of the present invention is to solve this problem and to provide a simple and lightweight linear motion electromagnetic actuator having excellent positioning performance. SOLUTION: By using a fixed magnetic field generating member 1 itself as a guide mechanism for operation of a mover 2, there is no need to provide a guide mechanism separately from a driving force generating mechanism, so that the volume and weight can be reduced, and the driving force can be reduced. The play that adversely affects the positioning performance due to the guide mechanism inside the force generating mechanism,
Factors such as friction can be reduced as much as possible. This allows
A simple, lightweight, linear motion electromagnetic actuator with excellent positioning performance can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic actuator for driving a mover with a force acting when a current flows in a magnetic field, and more particularly to a direct-acting electromagnetic actuator.

[0002]

2. Description of the Related Art Conventionally, in a direct-acting electromagnetic actuator, a rolling direct-acting bearing, a sliding direct-acting bearing, a pneumatic direct-acting bearing, and the like are provided separately from a driving force generating mechanism as an operation guide mechanism for a mover. What is provided is known.

[0003]

However, in the above-mentioned conventional mechanism, since the guide mechanism is provided separately from the driving force generating mechanism, there is a problem that the structure is complicated and the weight becomes heavy.

[0004] In order to solve this problem, an object of the present invention is to provide a direct-acting electromagnetic actuator that is simple, lightweight, and excellent in positioning performance.

[0005]

According to the electromagnetic actuator of the present invention, a current-carrying member held by a mover is provided in a space within a magnetic field generated by a fixed magnetic field-generating member. The movable element is driven by a force to generate the fixed magnetic field, and the fixed magnetic field generating member itself is used as a guide mechanism for operating the movable element, thereby eliminating the need to provide a guide mechanism separately from the driving force generating mechanism.

As a result, a simple, lightweight, linear motion type electromagnetic actuator having excellent positioning performance can be obtained.

[0007]

According to the first aspect of the present invention, an energizing member held by a mover is provided in a space within a magnetic field generated by a fixed magnetic field generating member, and a current flows through the energizing member. In this case, the movable element is driven by a force acting on the movable element, and the fixed magnetic field generating member itself is used as a guide mechanism for the operation of the movable element.Since the guide mechanism is provided in the driving force generating mechanism, There is an effect that the number of parts is small, and as a result, a simple and lightweight configuration can be achieved. Further, it is possible to reduce factors that adversely affect the positioning of the drive unit and the guide unit such as backlash and friction, thereby improving the positioning performance.

The invention described in claim 2 has an operation restricting mechanism for restricting an operation other than a required operation of the mover, and has an effect that the mover can operate smoothly only in a desired direction.

According to a third aspect of the present invention, a position detecting mechanism for detecting the position of the mover is provided, and the detection head is provided on the mover, and the position of the mover is directly detected and positioned. Since it is used for control or the like, it has the effect of achieving highly accurate positioning performance.

According to a fourth aspect of the present invention, a magnetic shielding member is provided along a fixed magnetic field generating member, and the fixed magnetic field generating member is generated outside a current-carrying member for passing a current receiving an acting force. Since the leakage of the magnetic field can be prevented, there is an effect that the energy of the magnetic field can be effectively used and the driving force acting on the mover can be improved.

According to a fifth aspect of the present invention, there is provided a rod-shaped manganese magnet having a multipole magnetized striped shape in an axial direction as a fixed magnetic field generating member.
Since an aluminum magnet is used and the permanent magnet has a performance capable of being anisotropically magnetized in the axial direction, a plurality of magnets are attached in the axial direction to generate a desired fixed magnetic field. This has the effect that the operation can be omitted. Further, since the permanent magnet can be formed into an arbitrary cross-sectional shape and has excellent mechanical strength, it has an effect that it can also serve as a structural member by itself.

According to a sixth aspect of the present invention, the fixed magnetic field generating member is provided with an operation restricting mechanism for restricting an operation other than a required operation of the mover. It has the effect of achieving a simple and reliable regulation function with few points.

According to a seventh aspect of the present invention, there is provided an operation restricting mechanism for restricting an operation other than a required operation of the mover, wherein a position detecting mechanism for detecting a position of the mover is provided. Since there is no need to separately provide a member for providing the scale, the number of parts is small, and a simple and reliable position detecting function can be achieved.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is a perspective view showing an electromagnetic actuator according to Embodiment 1 of the present invention. In the figure,
Reference numeral 1 denotes a fixed magnetic field generating member that generates a fixed magnetic field orthogonal to the axial direction, and is configured by a permanent magnet or an electromagnet. In the present embodiment, a rod-shaped manganese-aluminum magnet having a circular cross-sectional shape and multipole-polarized in a striped shape in the axial direction is used. Reference numeral 2 denotes a mover disposed outside the fixed magnetic field generating member 1 and capable of operating in the axial direction. In this embodiment, the mover 2 has an air-core shape concentrically disposed outside the fixed magnetic field generating member 1. I have. Reference numeral 3 denotes a current-carrying member for passing a current receiving an acting force. In the present embodiment, a coil composed of a plurality of coils concentrically wound around the outer periphery of the mover 2 is arranged in the axial direction. Become. Numeral 4 is a linear motion bearing fixed concentrically to the air core of the mover 2,
It is formed of a non-magnetic material such as resin and phosphor bronze. Reference numeral 5 denotes an operation restricting member provided in parallel with the fixed magnetic field generating member 1 and slidably fitted in a hole 6 provided in the movable element 2. 7
Is a position detecting head composed of a magnetoresistive element or the like, and is held so as not to move in the moving direction of the mover 2 with respect to the mover 2. Further, it is arranged so as to face the position detecting scale 8 arranged in parallel with the operation regulating member 5 with a certain gap. The position detecting scale 8 is formed by magnetizing the movable element 2 in a lattice pattern at a fine pitch in the operation direction. A position detection signal processing circuit 9 indicated by a virtual line sends a result of signal processing using a signal of the position detection head 7 as an input to a controller (not shown). 10
Is a movable cable for electrically connecting the position detection signal processing circuit 9 and the conducting member 3 to a controller (not shown). Reference numeral 11 denotes a magnetic shielding member provided in parallel with the fixed magnetic field generating member 1 and made of a magnetic material disposed so as to cover the fixed magnetic field generating member 1, the mover 2, and the conducting member 3.

FIG. 2 is a sectional view showing a main part of the electromagnetic actuator according to the first embodiment of the present invention. In FIG. 1, reference numerals 201, 202, 203, and 204 denote members constituting the mover 2. Reference numerals 201 and 202 are members at both ends in the axial direction of the mover 2 and fixedly sandwiching the member 203 for holding the energizing member 3 and simultaneously holding the linear motion bearings 401 and 402 in the air core. . Reference numeral 204 denotes a member fixed to the members 201 and 202 at both ends to take out the output of the actuator. In the above description, 20
Although an example has been described in which the components 1, 202, 203, and 204 are configured as separate components, they may be configured as an integral component. Further, in the figure, reference numerals 601 and 602 denote holes provided in members 201 and 202 at both ends of the mover 2 slidably fitted to the operation regulating member 5.

The operation of the electromagnetic actuator configured as described above will be described below. When a current controlled by a controller (not shown) flows through the energizing member 3 arranged orthogonal to the fixed magnetic field generated by the fixed magnetic field generating member 1, a force in the axial direction (X direction) acts on the energizing member 3. Similarly, a force in the axial direction (X direction) acts on the mover 2 integrated with the energizing member 3. At this time, the magnetic shielding member 1
1 functions to prevent the fixed magnetic field from leaking out of the current-carrying member 3 and improve the force acting on the mover 2. Mover 2
The movement in the rotation direction (R direction) is regulated by the movement regulating member 5 and the hole 6 provided in the mover 2, but is guided by the linear motion bearing 4 in the axial direction (X direction) to be operable. Has become. Therefore, when a force in the axial direction (X direction) acts on the mover 2, the mover 2 moves in the axial direction. Also,
The passage of the grid pitch of the position detecting scale 8 is read as a change in resistance or the like by the position detecting head 7 held by the mover 2 so as not to move in the operating direction (X direction) of the mover 2, and By processing the change in the position detection signal processing circuit 9, a rectangular wave output corresponding to the number of passes of the position detection scale 8 at the lattice pitch can be obtained. A controller (not shown) can measure the position of the mover 2 by counting the number of the rectangular waves. The control of the drive current flowing through the energizing member 3 is the same as the control of a known AC servomotor. With the above operation, a positioning control operation for controlling the position of the mover 2 can be achieved. If the operation of the mover 2 is output, a direct-acting electromagnetic actuator can be configured.

(Embodiment 2) FIG. 3 is a perspective view showing an electromagnetic actuator according to Embodiment 2 of the present invention. In the figure, the same components as those in FIG. 3 differs from FIG. 1 in that the configuration does not include the movement regulating member 5 and the hole 6 provided in the mover 2, and the fixed magnetic field generating member 1 and the linear motion bearing 4 have flat portions 101 and 403 is provided.

In the electromagnetic actuator configured as described above, the movement of the mover 2 in the rotation direction (R direction) is regulated by the flat portions 101 and 403. Other operations are the same as those in the first embodiment. Note that the shapes of 101 and 403 are not limited to flat shapes.
Even in the shape and other shapes, the rotation direction (R
The same operation can be performed as long as the operation in the direction can be regulated.

(Embodiment 3) FIG. 4 is a perspective view showing an electromagnetic actuator according to Embodiment 3 of the present invention. In the figure, the same components as those in FIG. 4 is different from FIG. 1 in that the position detecting scale 8 is not provided separately but is provided integrally with the operation regulating member 5. The position detecting scale 8 and the operation regulating member 5 can be implemented either by fixing separate objects to each other or by having the position detecting scale 8 itself have the function of the operation regulating member 5. The operation is the same as in the first embodiment.

In the above description, an example has been described in which the direct-acting bearing 4 is constituted by a sliding type bearing. However, a rolling type bearing or a hydrostatic type bearing can be similarly applied.

The position detection scale 8 and the position detection head 7 have been described as being of the magnetic type, but they can also be implemented in an optical type or a type of detecting the position based on other principles. .

[0022]

As described above, according to the electromagnetic actuator of the present invention, a driving force generating mechanism, that is, a fixed magnetic field generating member, and a movable element 2 for holding an energizing member for passing a driving current and extracting an operation output. By providing a guide mechanism for moving the mover inside the above structure, the advantageous effects of reducing the number of parts, being simple, lightweight, and having excellent positioning performance can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an electromagnetic actuator according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the electromagnetic actuator according to the first embodiment of the present invention;

FIG. 3 is a perspective view showing an electromagnetic actuator according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing an electromagnetic actuator according to a third embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 fixed magnetic field generating member 2 mover 3 conducting member 4 linear motion bearing 5 operation restricting member 6 hole 7 position detecting head 8 position detecting scale 9 position detecting signal processing circuit 10 movable cable 11 magnetic shielding member

Claims (7)

[Claims] An energizing member held by a movable element is provided in a space within a magnetic field generated by a fixed magnetic field generating member, and the movable element is driven by a force acting when a current flows through the energizing member; and An electromagnetic actuator, wherein the fixed magnetic field generating member itself is used as a guide mechanism for the operation of the mover. 2. The electromagnetic actuator according to claim 1, further comprising an operation restricting mechanism for restricting an operation other than a required operation of the mover. 3. The electromagnetic actuator according to claim 1, further comprising a position detection mechanism for detecting a position of the mover, and further comprising a detection head provided on the mover. 4. The electromagnetic actuator according to claim 1, wherein a magnetic shielding member is provided along the fixed magnetic field generating member. 5. The electromagnetic actuator according to claim 1, wherein a rod-shaped manganese-aluminum magnet multipole-polarized in an axial direction is used as the fixed magnetic field generating member. 6. The electromagnetic actuator according to claim 2, wherein the fixed magnetic field generating member is provided with an operation restricting mechanism for restricting an operation other than a required operation of the mover. 7. The electromagnetic actuator according to claim 2, wherein a position detecting mechanism for detecting a position of the mover is provided in an operation restricting mechanism for restricting an operation other than a required operation of the mover.